阅读说明：本技术 安装式调心装置和电动工具 (Installation formula aligning device and electric tool ) 是由 中村大治郎 于 2019-10-09 设计创作，主要内容包括：本发明的目的在于,提供能够对基轴支架所保持的基轴进行调心从而防止旋转治具旋转时的芯偏移的安装式调心装置以及在基轴支架上安装有安装式调心装置的电动螺丝刀。调心适配器(40(40X))设置有：调心轴承(50(50a、50b)),其与贯穿贯通孔(40a(40Xa))的旋转治具5的基轴6抵接而进行调心；以及安装单元(90(90X)),其从轴向前端侧Lf插入而将调心轴承(50(50a、50b))安装在构成对基轴(6)进行保持的基轴支架(1)的支架体(10)的规定的位置,该调心适配器(40(40X))构成为安装于基轴支架(1)而对由基轴支架(1)保持的基轴(6)进行调心。(The invention aims to provide a mounting type aligning device which can align a base shaft held by a base shaft bracket so as to prevent core deviation when a rotary jig rotates, and an electric screwdriver which is provided with the mounting type aligning device on the base shaft bracket. A center-adjusting adapter (40(40X)) is provided with: a self-aligning bearing (50(50a, 50b)) which abuts against the base shaft 6 of the rotating jig 5 penetrating the through hole (40a (40Xa)) to align the rotating jig; and a mounting unit (90(90X)) that is inserted from the axial front end side Lf and mounts the self-aligning bearing (50(50a, 50b)) at a predetermined position of a bracket body (10) that constitutes a base shaft bracket (1) that holds the base shaft (6), wherein the self-aligning adapter (40(40X)) is configured to be mounted to the base shaft bracket (1) and align the base shaft (6) held by the base shaft bracket (1).)

1. A mounted centering device provided with:

a centering unit which abuts against a base shaft of the rotating jig penetrating the through hole to perform centering; and

a mounting member that is inserted from a distal end side and mounts the aligning unit to a distal end of a holder main body constituting a base shaft holder that holds the base shaft,

the installation type aligning device is installed on the base shaft support and aligns the base shaft held by the base shaft support.

2. The center-mounted aligning device of claim 1,

the mounting component is provided with a position adjusting part,

the position adjusting portion performs position adjustment so that the axial direction of the aligning unit coincides with the axial direction of the holder main body by a tip end tapered surface that is formed at the tip end of the base shaft insertion hole of the holder main body and that has a diameter that expands toward the tip end.

3. A mounted centering device according to claim 1 or 2,

at least a part of the mounting member is constituted by a magnet magnetically attracted to the holder main body as a magnetic metal.

4. A mounted centering device according to claim 3,

the mounting member made of the magnet is provided with a facing portion facing a front end surface of the holder main body,

the center adjusting device of the fitting type has a radially outer member made of a magnetic metal and spanning the fitting member and the bracket body on the radially outer side.

5. A center-mounted aligning device according to any one of claims 1 to 4,

the center adjusting unit is provided with a center adjusting member that performs center adjustment by abutting from at least three directions of the base shaft inserted into the through hole.

6. A mounted centering device according to claim 5,

this installation formula aligning device is provided with:

an inclined member having an axially inclined surface inclined with respect to an axial direction in a direction of guiding the center adjusting member in contact with the axially inner side of the through hole; and

and a biasing unit that biases the center adjusting member in an axial direction inclined with respect to the axial direction in a direction in which the center adjusting member is guided to the inside in the radial direction of the through hole.

7. The center-mounted aligning device of claim 6,

the aligning member is provided with:

a tip-side aligning member that aligns the base shaft on a tip side in an axial direction; and

a base end side aligning member that aligns the base shaft on the base end side in the axial direction,

the axial inclined plane is provided with:

a tip-side inclined surface that guides the tip-side aligning member that is in contact with the tip-side inclined surface radially inward; and

a base end side inclined surface for guiding the base end side aligning member in contact with the base end side inclined surface to the radial inner side,

the tilt member is provided with:

a tip-side inclined member having the tip-side inclined surface; and

a base end side inclined member having the base end side inclined surface,

the biasing unit is disposed between the distal-side aligning member and the proximal-side aligning member in the axial direction, and biases the distal-side aligning member and the proximal-side aligning member in a direction in which the distal-side aligning member and the proximal-side aligning member are separated from each other in the axial direction.

8. A mounted centering device according to claim 6 or 7,

the mounting type center adjusting device is provided with an annular holding member which holds a plurality of center adjusting members which are provided with a circumferential interval therebetween and has an axial through hole which penetrates in an axial direction,

the axial through hole constitutes a part of the through hole.

9. An electric power tool having:

a drive device; and

a rotation transmission unit for transmitting the rotation force of the driving device on the axis,

a center-mounted-type aligning device according to any one of claims 1 to 8 mounted on the base shaft bracket.

Technical Field

The present invention relates to a mounting type centering device that is mounted on a base shaft holder into which a base shaft of a rotary jig such as a driver bit or a drill is inserted and held, for example, to center the base shaft, and an electric screwdriver in which the mounting type centering device is mounted on the base shaft holder.

Background

Conventionally, as a base shaft holder disposed at the tip of an electric screwdriver or the like, a base shaft holder has been proposed in which a base shaft of a rotary jig held by the holder is not accidentally detached (see patent document 1).

The base shaft bracket is composed of the following components: a holder main body having a base shaft insertion hole into which a base shaft of the rotary jig is removably inserted, and a through hole configured to allow a steel ball locked in a locking groove formed in an outer surface of the base shaft to move; a steel ball disposed in the through hole; a cylindrical external fitting member which is externally fitted to the holder main body to be slidable; and a spring that urges the external fitting member toward the proximal end side of the holder main body.

When the base shaft is inserted into the base shaft insertion hole of the base shaft holder, the outer fitting member causes the steel ball to protrude from and retract from the inner peripheral surface of the base shaft insertion hole and to be locked in the locking groove, so that the base shaft inserted into the base shaft holder can be held without being accidentally disengaged.

However, since the base shaft insertion hole into which the base shaft can be inserted is formed slightly larger than the base shaft, when the insertion position or the insertion direction of the base shaft is slightly deviated from the rotation center in the inserted state or in use, core misalignment, which is called dimensional deviation, may occur.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open No. 2006-198755

Disclosure of Invention

Problems to be solved by the invention

Therefore, an object of the present invention is to provide a mounting type aligning device capable of aligning the base shaft held by a base shaft holder and preventing a core shift (dimensional deviation) when the rotary jig rotates, and an electric screwdriver having the mounting type aligning device mounted on the base shaft holder.

Means for solving the problems

The present invention is characterized in that the mounting type aligning device includes: a centering unit which abuts against a base shaft of the rotating jig penetrating the through hole to perform centering; and a mounting member inserted from a distal end side to hold the aligning unit at a distal end of a holder main body constituting a base shaft holder holding the base shaft, the mounting type aligning device being mounted to the base shaft holder to align the base shaft held by the base shaft holder.

The rotary jig may be a drill bit, a cross or a straight screwdriver bit, or the like that is attached to a hand tool or an electric tool and rotates, and a base shaft of the rotary jig is also referred to as a tool shank.

The base shaft includes various cross-sectional shapes such as a polygonal cross section such as a hexagonal cross section and a circular cross section.

The above-described aligning unit may be a mechanism that moves in the radial center direction and comes into contact with the outer surface of the base shaft, or a mechanism that comes into contact with the outer surface of the base shaft by deformation such as extension in the radial center direction. Further, the plurality of centering units may be configured to perform centering by abutting against the base shaft at a plurality of portions, and may be configured by a single member such as an elastic ring that is fitted to the outer peripheral surface of the base shaft so as to bias the outer peripheral surface in the radially inward direction, for example.

According to the present invention, the base shaft held by the base shaft holder can be aligned to prevent the core from shifting when the rotary jig rotates.

Specifically, by attaching a mounting type aligning device to a base shaft holder holding the base shaft, the base shaft held by the base shaft holder can be aligned by an aligning unit, and core misalignment when the rotary jig rotates can be prevented.

In an aspect of the present invention, the mounting member may be provided with a position adjustment portion that performs position adjustment so that an axial direction of the center adjustment unit coincides with an axial direction of the holder main body by a tip tapered surface that is formed at a tip of the base shaft insertion hole of the holder main body and that has a diameter that increases toward the tip.

The position adjusting portion may be a single tapered surface or a plurality of tapered surfaces spaced apart from each other at predetermined intervals, the position of which can be adjusted by the tip tapered surface so that the axial direction of the aligning unit coincides with the axial direction of the holder main body, or may be a member that abuts against the tip tapered surface at a plurality of locations.

According to the present invention, the center adjusting device of the installation type can be easily installed to the holder main body in an axially uniform manner.

Specifically, the position adjustment is performed by matching a position adjustment portion provided in the base end side inclined member with a tip end tapered surface formed at a tip end of the base shaft insertion hole of the holder main body, so that the axial direction of the center adjusting device of the installation type coincides with the axial direction of the holder main body. Therefore, the center adjusting device of the installation type can be easily installed to the holder main body in an axially uniform manner. Therefore, the base shaft can be accurately aligned with respect to the base shaft holder.

In an embodiment of the present invention, at least a part of the attachment member may be constituted by a magnet magnetically attracted to the holder main body made of a magnetic metal.

The at least part of the magnet may be formed by the mounting member entirely formed by the magnet, or may be formed by magnetizing only a part of the mounting member, or may be formed by assembling a magnet as another member to the member forming the mounting member.

According to the present invention, the mounting type center adjusting device can be easily and detachably mounted on the bracket main body which is made of magnetic metal.

In detail, for example, compared to a case where a screw-engagement means such as a screw thread is provided on an attachment member of the mounting type center adjusting device and the screw-engagement means is screwed with the holder main body to be attached and detached, the mounting type center adjusting device can be easily attached to the holder main body by a magnetic force of a magnet constituting at least a part of the attachment member. Further, the center adjusting device of the attachment type can be easily detached from the holder main body. That is, the mounting type centering device can be easily attached to and detached from the holder main body.

Further, although the mounting member of the mounting type center adjusting device is provided with the screwing means such as the screw thread and detachably screwed with the holder main body as described above, when the screwing means is not provided in the holder main body of the base shaft holder to be used, the screwing means needs to be provided in the holder main body. In contrast, since the center adjusting device of the installation type is easily attached to the holder main body by the magnetic force of the magnet constituting at least a part of the attachment member, the center adjusting device of the installation type can be easily attached to and detached from the base shaft holder used without any processing as long as the holder main body is made of a magnetic metal.

In addition, as an aspect of the present invention, the mounting member made of the magnet may be provided with a facing portion facing a front end surface of the holder main body, and the center adjusting device of the mounting type may have a radially outer member made of a magnetic metal and extending radially outward across the mounting member and the holder main body.

The radially outer member that spans the mounting member and the stent body radially outward may also span in direct contact with the radially outer side of the mounting member and the stent body. Alternatively, another member made of a magnetic material may be interposed between the radially outer member and the mounting member or between the radially outer member and the holder main body so as to straddle the other member.

According to the present invention, the mounting type centering device can be easily attached to and detached from the holder main body by magnetically attracting the mounting member made of a magnet to the holder main body. Further, since the radially outer member is provided so as to extend radially outward across the mounting member and the holder main body, a magnetic circuit can be formed by the mounting member, the holder main body, and the radially outer member, and the mounting member can be firmly mounted on the main body as compared with mounting by magnetic attraction alone.

Further, since the facing surface portion of the mounting member made of the magnet is magnetically attracted to the holder main body so as to face the distal end surface, that is, the contact area between the mounting member and the holder main body is increased, the stability of the mounting state can be improved, and more firm fixing can be achieved.

Further, since the mounting member, the holder main body, and the radially outer member constitute a magnetic circuit, the base shaft made of a magnetic metal is not inadvertently attracted, and operability can be improved.

In an aspect of the present invention, the center adjusting unit may be provided with a center adjusting member that performs center adjustment by coming into contact with the base shaft inserted into the through hole from at least three directions.

According to the present invention, the aligning member can be abutted from at least three directions to perform alignment with high accuracy.

Further, the aligning member that performs alignment by coming into contact with at least three directions of the base shaft may be a plurality of aligning members such as spherical bodies or rolling elements such as rollers that perform alignment by coming into contact with at least three directions of the base shaft. Alternatively, at least three portions of one aligning member may abut against at least three directions of the base shaft to align the center. Further, it is preferable that at least three directions are substantially equally spaced in the circumferential direction, and for example, it is preferable that the base shaft having a hexagonal cross section is abutted from three directions or six directions.

In addition, as an aspect of the present invention, the present invention may further include a tilt member having an axial direction inclined surface inclined with respect to an axial direction in a direction to guide the abutting center adjusting member to a radial direction inside of the through hole, and a biasing unit biasing the abutting center adjusting member to the axial direction inclined surface inclined with respect to the axial direction in the direction to guide the abutting center adjusting member to the radial direction inside of the through hole.

The axial inclined surface may be a curved surface, a flat surface, or a combination thereof, as long as the axial inclined surface is inclined with respect to the axial direction in a direction of guiding the abutting aligning member to the inside in the radial direction of the base shaft insertion hole.

The biasing means for biasing the center adjusting member in the direction in which the axial inclined surface approaches the center adjusting member may directly abut against the center adjusting member to bias the center adjusting member. Alternatively, the center adjusting member may be biased via a holding member having an axial through hole penetrating in the axial direction while holding a circumferential interval of the plurality of center adjusting members, in contact with an annular holding member described later.

According to the present invention, the base shaft held by the base shaft holder can be aligned, and core shift during rotation of the rotary jig can be further prevented.

Specifically, the center adjusting member biased by the biasing means abuts against an axially inclined surface provided on the inclined member, and moves in the radial center direction by the axially inclined surface or the biasing force of the biasing means acts in the radial center direction via the center adjusting member. Therefore, the base shaft inserted into the base shaft insertion hole of the holder body can be aligned by abutting in at least three directions. Therefore, the base shaft held by the base shaft holder can be aligned, and core shift during rotation of the rotary jig can be further prevented.

In addition, according to an aspect of the present invention, the center adjusting member includes: a tip-side aligning member that aligns the base shaft on a tip side in an axial direction; and a base end side aligning member that aligns the base shaft on the base end side in an axial direction, the axial direction inclined surface being provided with: a tip-side inclined surface that guides the tip-side aligning member that is in contact with the tip-side inclined surface radially inward; and a base end side inclined surface that guides the base end side aligning member that is in contact therewith radially inward, the inclined member being provided with: a tip-side inclined member having the tip-side inclined surface; and a base end side inclined member having the base end side inclined surface, wherein the biasing unit is disposed between the tip side aligning member and the base end side aligning member in the axial direction, and biases the tip side aligning member and the base end side aligning member in a direction of being separated from each other in the axial direction.

According to the present invention, since the tip side aligning member and the base side aligning member align the center of the base shaft, that is, align the base shaft at two positions in the axial direction, the base shaft can be aligned with higher accuracy.

Further, the center adjusting member includes a tip-side axial center adjusting member for aligning the base shaft on the tip side in the axial direction and a base-side axial center adjusting member for aligning the base shaft on the base side in the axial direction, and the center adjusting member includes a tip-side inclined surface for abutting the tip-side axial center adjusting member and guiding the tip-side axial center adjusting member radially inward and a base-side inclined surface for abutting the base-side axial center adjusting member and guiding the base-side axial center adjusting member radially inward, therefore, the urging means for urging the center adjusting member and the axial inclined surface in the direction of approaching each other urges the tip end side center adjusting member and the tip end axial inclined surface in the direction of approaching each other, and a force is applied in a direction in which the base end side aligning member and the base end axial inclined surface approach each other.

In this way, the urging means urges the distal end side aligning member and the distal end axial inclined surface in the direction approaching each other, and urges the proximal end side aligning member and the proximal end axial inclined surface in the direction approaching each other. Therefore, it is possible to apply a force in a direction in which the front end side aligning member and the front end axial inclined surface approach each other, and to apply a force in a direction in which the base end side aligning member and the base end axial inclined surface approach each other, by a single urging unit. Alternatively, the center adjusting member may have a biasing means for biasing the center adjusting member in a direction in which the center adjusting member approaches the tip axial inclined surface, and the base adjusting member may have a biasing means for biasing the center adjusting member in a direction in which the center adjusting member approaches the tip axial inclined surface.

The inclination directions of the base end side aligning member and the base end axial inclined surface may be opposite directions or the same direction. The inclination angles of the base end side aligning member and the base end axial inclined surface may be the same or different.

In addition, as an aspect of the present invention, the present invention may further include: a tip-side reverse-inclination contact member that is disposed between the tip-side aligning member and the biasing unit, has a tip-side axial reverse-inclination surface that is inclined in an axial direction in a direction opposite to the tip-side axial-inclination surface, and that is in contact with the tip-side aligning member; and a base end side reverse inclination contact member that is disposed between the base end side aligning member and the biasing unit, has a base end side axial reverse inclination surface that is inclined in an opposite direction to the base end side axial inclination surface with respect to an axial direction, and is in contact with the base end side aligning member.

In this case, the biasing force of the biasing unit can be divided into a direction in which the distal end side aligning member is biased toward the distal end side axial direction inclined surface and a direction in which the distal end side aligning member is in contact with the base shaft, that is, a radial direction. Further, the base end side aligning member may be biased in a direction of biasing the base end side aligning member to the base end side axial direction inclined surface and in a radial direction which is a direction in which the base end side aligning member abuts against the base shaft. Therefore, even if a force directed radially outward acts on the distal end side aligning member or the proximal end side aligning member from the driven proximal end side, the force can be resisted by the urging force of the urging means.

The distal-end-side axial inclined surface and the distal-end-side axial counter-inclined surface restrict a radially outer side of the distal-end-side aligning member in an aligning state in which the distal-end-side axial inclined surface and the distal-end-side axial counter-inclined surface abut against the base shaft in a state in which the biasing force of the biasing unit is applied, so as to form a splayed shape in an axial cross section. Further, the base end side axial direction inclined surface and the base end side axial direction reverse inclined surface restrict radially outer sides of the base end side aligning member in the aligned state so as to be splayed in an axial cross section in a state where the biasing force of the biasing means is applied. Therefore, even if a force directed radially outward acts on the self-aligning member from the driven base end side, the force can be resisted by the urging force of the urging means.

Therefore, the base shaft held by the base shaft holder can be aligned, and the core shift when the rotary jig rotates can be reliably prevented.

In an aspect of the present invention, an annular holding member may be provided that has an axial through hole that penetrates in an axial direction while holding a circumferential interval between the plurality of aligning members, and the axial through hole may constitute a part of the through hole.

According to the present invention, the base shaft can be aligned and held with high accuracy in the through hole that is a part of the axial through hole of the holding member, that is, the base shaft held by the base shaft holder can be aligned, and core misalignment during rotation of the rotary jig can be more reliably prevented.

Further, by holding a plurality of the aligning members in the annular holding member, the aligning unit can be configured while maintaining the interval in the circumferential direction, and the assembling property of the mounting type aligning unit having the aligning unit can be improved.

In addition, according to an aspect of the present invention, the electric power tool includes a driving device and a rotation transmitting device that transmits a rotational force of the driving device to an axial center thereof, and the center-fitted aligning unit is attached to the base shaft bracket.

According to the present invention, the base shaft can be aligned, and the rotating jig can be rotated without causing core misalignment.

The electric tool may be any electric tool that can be attached to a rotary jig such as a driver bit or a drill and that can rotate a rotary jig such as an electric screwdriver or an impact screwdriver.

Effects of the invention

According to the present invention, it is possible to provide a mounting type centering device capable of aligning the base shaft held by the base shaft holder and preventing a core from being displaced when the rotary jig rotates, and an electric screwdriver in which the mounting type centering device is mounted on the base shaft holder.

Drawings

Fig. 1 is a front view showing an electric power tool in which a center adjusting adapter is attached to a base shaft bracket.

Fig. 2 is a perspective view of the base shaft bracket in a state where the aligning adapter is attached.

Fig. 3 is a perspective view of the base shaft bracket before the self-aligning adapter is mounted.

Fig. 4 is an exploded explanatory view showing components of the aligning adapter and the front or rear surface and the side or cross-section of the base shaft holder.

Fig. 5 is an exploded perspective view of each component of the aligning adapter as viewed from the front side.

Fig. 6 is an exploded perspective view of each component of the aligning adapter as viewed from the back side.

Fig. 7 is a perspective view of the aligning adapter.

Fig. 8 is a longitudinal sectional view of the base shaft bracket with the self-aligning adapter installed.

Fig. 9 is an explanatory diagram of the alignment by the alignment adapter.

Fig. 10 is an explanatory diagram illustrating a longitudinal sectional view of the base shaft holder to which the self-aligning adapter is attached.

Fig. 11 is a front view of an electric power tool in which the aligning adapter of embodiment 2 is attached to a base shaft bracket.

Fig. 12 is a perspective view of the base shaft holder in a state where the self-aligning adapter of embodiment 2 is attached.

Fig. 13 is a perspective view of the base shaft bracket before the self-aligning adapter of embodiment 2 is attached.

Fig. 14 is an exploded explanatory view showing components of the aligning adapter according to embodiment 2 together with the front or rear surface and the side or cross-section of the base shaft holder.

Fig. 15 is an exploded perspective view of each component of the aligning adapter according to embodiment 2, as viewed from the front side.

Fig. 16 is an exploded perspective view of each component of the self-aligning adapter according to embodiment 2, as viewed from the back side.

Fig. 17 is a perspective view of the aligning adapter according to embodiment 2.

Fig. 18 is a longitudinal sectional view of the base shaft bracket to which the self-aligning adapter of embodiment 2 is attached.

Fig. 19 is an explanatory diagram of the alignment by the alignment adapter of embodiment 2.

Fig. 20 is an explanatory diagram illustrating a vertical cross-sectional view of the base shaft holder to which the self-aligning adapter according to embodiment 2 is attached.

Detailed Description

An embodiment of the present invention will be described in detail below with reference to the accompanying drawings.

The aligning adapter 40, the base shaft bracket 1 to which the aligning adapter 40 is attached, and the electric power tool K will be described with reference to fig. 1 to 10.

Fig. 1 is a front view showing an electric power tool K in which a center adjusting adapter 40 is attached to a base shaft holder 1, fig. 2 is a perspective view showing the base shaft holder 1 in a state in which the center adjusting adapter 40 is attached, and fig. 3 is a perspective view showing the base shaft holder 1 before the center adjusting adapter 40 is attached.

Fig. 4 is an exploded explanatory view showing a front surface, a back surface, a side surface, or a cross section of each component of the base shaft holder 1 and the aligning adapter 40.

In detail, the base shaft holder 1, the outer fitting ring 92, the accommodating cylindrical member 93, the abutment ring 60, the aligning ball 51, the retainer 52, and the coil spring 64 are shown in a longitudinal sectional view and a front view, and the tapered member 91, the front end side inclined surface ring 70, and the front end cover 80 are shown in a longitudinal sectional view and a rear view.

The center ball 51 and the retainer 52 constituting the center bearing 50(50a, 50b) are shown in a cross section of the annular retainer 52 passing through the housing portion 55, that is, a-a cross section in front view of the center ball 51 and the retainer 52.

Fig. 5 is an exploded perspective view of the components of the front side center-adjusting adapter 40, fig. 6 is an exploded perspective view of the components of the back side center-adjusting adapter 40, and fig. 7 is a perspective view of the center-adjusting adapter 40. In fig. 7, the center-adjusting ball 51 is not shown, and a part of the center-adjusting adapter 40 on the near side is cut out.

Fig. 8 is a longitudinal sectional view showing the base shaft holder 1 to which the self-aligning adapter 40 is attached, fig. 9 is an explanatory view showing the alignment by the self-aligning adapter 40, and fig. 10 is an explanatory view showing the base shaft holder 1 to which the self-aligning adapter 40 is attached in a longitudinal sectional view.

Specifically, (a) of fig. 9 is a cross-sectional view showing the c-c direction of fig. 8, and (b) of fig. 9 is an enlarged view showing a portion a of fig. 9 (a). Fig. 10 (a) is an enlarged view of a portion a of fig. 8 showing a state in which the base shaft holder 1 of the center adjusting adapter 40 is attached to the distal end of the small-diameter front main body portion 12 of the base shaft holder 1, and fig. 10 (b) is an enlarged view of a portion a showing a state before the center adjusting adapter 40 is attached.

The aligning adapter 40 of the present invention is attached to the base shaft holder 1 attached to the front end of the electric tool K, and aligns the rotary jig 5 held by the base shaft holder 1. The electric power tool K includes, for example: a housing 2 having a handle portion 2a for a user to hold during use; a motor M disposed inside the casing 2 and rotatable in forward and reverse directions; and a rotation transmission mechanism not shown.

The base shaft holder 1 is a member that is disposed in front of the housing 2 and holds the base shaft 6 of the rotating jig 5. By operating the trigger 2b disposed on the handle portion 2a, the rotational driving force of the motor M, which is provided in the housing and can rotate in the forward and reverse directions, is transmitted by the rotation transmission mechanism, and the base shaft holder 1 is rotated.

Before describing the base shaft holder 1, the rotary jig 5 held by the base shaft holder 1 will be described. As shown in fig. 2, 5, 6, and 9, the base shaft 6 on the axial distal end side Lf of the rotary jig 5 such as a driver bit or a drill has a hexagonal cross section. The rotary jig 5 is formed with a locking groove 7 having an arc-shaped longitudinal cross section in the circumferential direction, and a base end inclined portion 8 on the axial base end side Lb of the base shaft 6 protrudes in a tapered substantially conical shape toward the rear end side.

The outer surface of the base shaft 6, which is formed in a planar shape having a hexagonal cross section, is an outer plane 6a, and the corners 6b are defined between the outer planes 6 a. The axial base end side Lb of the base end inclined portion 8 is a peak portion 8 a. The locking groove 7 is formed in an arc shape having a cross section slightly larger than the diameter of the anti-slip ball 21 described later.

As shown in fig. 3 and 4, the base shaft holder 1 attached to the electric power tool K is configured by combining a holder body 10, a retaining ball 21, a sleeve 30, a sleeve spring 22, a fixing ring 23, and a clamp ring 24 as main components.

The base shaft holder 1 is a commonly used base shaft holder, and is not limited to the above configuration as long as the alignment inclined surface 191 and the distal end surface 192 are formed on the distal end surface of the small-diameter front main body portion 12 of the holder body 10. In the present embodiment, the alignment inclined surface 191 is named for the function so that the axial direction L of the center adjusting adapter 40 coincides with the axial direction L of the base shaft holder 1 as described later, but the alignment inclined surface 191 is an inclined surface for guiding the insertion of the base shaft 6 into the base shaft insertion hole 11.

In fig. 3, the holder body 10 side in the axial direction L passing through the center of the elements constituting the base shaft holder 1 is defined as an axial base end side Lb, and the side on which the positioning inclined surface 191 is formed is defined as an axial tip end side Lf.

The holder body 10 is formed in a substantially cylindrical shape having a base shaft insertion hole 11 formed therein in the axial direction L from the axial distal end side Lf toward the axial base end side Lb. The holder body 10 is composed of a small-diameter front body portion 12 disposed on the axial front end side Lf, and a large-diameter rear body portion 13, and the large-diameter rear body portion 13 is disposed on the axial base end side Lb of the small-diameter front body portion 12, and is provided with flanges 14 extending in two directions radially outward on the axial base end side Lb.

The base shaft insertion hole 11 in the axial direction L from the axial leading end side Lf toward the axial base end side Lb in the holder body 10 is a space extending in the axial direction L and having a hexagonal shape when viewed from the left side surface. Further, a tapered space 111, which is tapered so as to be reduced in diameter toward the axial base end side Lb, is provided at a base end portion (right end portion in fig. 4) of the base shaft insertion hole 11.

Further, two slip-off preventing holes 17 are provided at equal intervals in the circumferential direction on the axial base end side Lb of the small-diameter front main body portion 12, and the slip-off preventing holes 17 communicate radially with the base shaft insertion hole 11 described later on the outside of the holder body 10 and receive a slip-off preventing ball 21 described later.

The slip-off preventing hole 17 is a radial through hole that accommodates a slip-off preventing ball 21 described later so as to be movable in the radial direction and communicates the outer side in the radial direction of the holder body 10 with the base shaft insertion hole 11, and is provided at two circumferentially opposed positions.

The slip-off preventing hole 17 is formed with a diameter slightly larger than the diameter of the received slip-off preventing ball 21, and a stopper (not shown) for preventing the received slip-off preventing ball 21 from falling into the base shaft insertion hole 11 is formed radially inside the slip-off preventing hole 17. The slip-off preventing hole 17 is formed with a depth shorter than the diameter of the received slip-off preventing ball 21, and the radial inner side of the received slip-off preventing ball 21 is exposed from the base shaft insertion hole 11.

Further, a circumferential engagement groove 18 that engages with a snap ring 24 described later is formed in the outer peripheral surface of the small-diameter front main body portion 12 of the holder body 10.

Further, an alignment inclined surface 191 spreading in a trumpet shape from the axial distal end side Lf to the axial base end side Lb is formed on the distal end inner surface of the small-diameter distal body portion 12, and a distal end surface 192 in a direction orthogonal to the axial direction L is formed on the radial outer side thereof.

The sleeve 30 is formed in a substantially cylindrical shape fitted to the small-diameter front body 12 of the holder 10 from the axial front end side Lf, and specifically, is formed by integrally arranging a front body 30a and a rear body 30b having a smaller diameter than the front body 30a in this order from the axial front end side Lf in the axial direction L. A through space penetrating in the axial direction L is formed inside.

The front body portion 30a has an inner diameter that is one step larger than the outer diameter of the small-diameter front body portion 12.

Further, a protrusion limiting portion 32 is provided on an inner surface between the front body portion 30a and the rear body portion 30b, and the protrusion limiting portion 32 protrudes radially inward and on the axial front end side Lf in a longitudinal section.

The sleeve spring 22 is a so-called coil spring that is biased in the axial direction L, and is formed with a diameter that is fitted around the small-diameter front main body portion 12 of the holder 10 and is disposed between the small-diameter front main body portion 12 and the inner surface of the front main body portion 30a that constitutes the sleeve 30 in the attached state.

The retainer ring 23 is a plate-like ring body fitted around the small-diameter front body portion 12, and the retainer ring 24 is a spring ring formed of a wire spring having a circular shape and a portion opened, and fitted around the engagement groove 18 provided on the outer peripheral surface of the small-diameter front body portion 12. The snap ring 24 has a diameter section longer than the depth of the engaging groove 18 to be fitted. The fixing ring 23 is configured to close the axial direction front end side Lf of the housing space of the sleeve 30 in the assembled state.

The base shaft bracket 1 having the above-described components is configured such that the sleeve 30 is fitted to the small-diameter front body portion 12 in a state where the retaining ball 21 is accommodated in the retaining hole 17, and the sleeve spring 22 is inserted from the axial front end side Lf. At this time, the sleeve spring 22 is disposed between the small-diameter front body portion 12 and the sleeve 30. Further, the fixing ring 23 is attached from the front, and the snap ring 24 is engaged with the engagement groove 18.

As described above, the snap ring 24 is engaged with the engagement groove 18 to restrict the movement of the axial distal end side Lf of the fixed ring 23 fitted around the small-diameter front body portion 12, and the fixed ring 23 serves as a reaction force of the axial distal end side Lf of the sleeve spring 22. Therefore, the sleeve 30 is assembled in a state of being biased toward the axial base end side Lb by the sleeve spring 22 having the fixed ring 23 as a reaction force.

In the base shaft bracket 1 in which the elements are assembled in this way, the projection restricting portions 32 of the sleeve 30 are disposed radially outward of the retaining balls 21 accommodated in the retaining holes 17, and therefore, the movement of the retaining balls 21 radially outward can be restricted. Therefore, in order to insert the base shaft 6 of the rotating jig 5 into the base shaft insertion hole 11 and hold the base shaft 6 by the base shaft holder 1, the base shaft 6 is inserted into the base shaft insertion hole 11 from the axial distal end side Lf, but the slip-off preventing balls 21 exposed from the base shaft insertion hole 11 are in contact with the base end inclined portion 8 and cannot be inserted.

Here, when the sleeve 30 is moved toward the axial direction distal end side Lf against the urging force of the sleeve spring 22, the projection restricting portion 32 located radially outward of the retaining ball 21 is also moved toward the axial direction distal end side Lf, and therefore the retaining ball 21 can be moved radially outward by the projection restricting portion 32.

In this state, if the base shaft 6 is further moved toward the axial base end side Lb, the base end inclined portion 8 of the base shaft 6 can move and insert the slip-off preventing balls 21 radially outward. Therefore, when the movement of the sleeve 30 on the axial distal end side Lf is released, the sleeve 30 tends to move toward the axial base end side Lb by the urging force of the sleeve spring 22, but the slip prevention balls 21 slide on the outer flat surface 6a of the base shaft 6, so that the sleeve 30 cannot move toward the axial base end side Lb.

Next, the base shaft 6 is moved toward the axial base end side Lb, and when the locking groove 7 is at a position corresponding to the release preventing ball 21, the release preventing ball 21 moves radially inward, and the release preventing ball 21 is fitted into the locking groove 7. Then, as the retaining ball 21 moves radially inward, the sleeve 30 moves toward the axial base end side Lb by the biasing force of the sleeve spring 22, and the movement of the retaining ball 21 radially outward is restricted by the protrusion restricting portion 32. Therefore, the base shaft 6 with the retaining ball 21 retained in the retaining groove 7 can be prevented from coming off the base shaft holder 1.

In the state where the base shaft 6 is held by the base shaft holder 1 having the retaining balls 21 retained in the retaining grooves 7, the base end inclined portion 8 on the axial base end side Lb of the base shaft 6 abuts against the tapered space 111 of the base shaft insertion hole 11. Specifically, the base end inclined portion 8 protruding toward the axial base end side Lb abuts against the peripheral wall of the tapered space 111 which is a tapered space tapered toward the axial base end side Lb, and therefore the center axis of the base end inclined portion 8 which is the end portion of the base shaft 6 on the axial base end side Lb with respect to the axial direction L of the base shaft holder 1 can be aligned.

Further, by using the rotation jig 5, when a force in the axial direction base end side Lb acts on the rotation jig 5 (base shaft 6), the base end inclined portion 8 is pressed against the tapered space 111, so that the axial direction base end side Lb of the rotation jig 5 can be further aligned with respect to the base shaft bracket 1.

However, although the base end inclined portion 8 is aligned by the tapered space 111 as described above, the base shaft insertion hole 11 is formed slightly larger than the base shaft 6 so that the base shaft 6 can be inserted. Therefore, if the insertion position or the insertion direction of the base shaft 6 is slightly deviated from the rotation center in the inserted state or in use, core misalignment called dimensional deviation (Run out) occurs.

Hereinafter, the aligning adapter 40 that is attached to the tip of the base shaft holder 1 and aligns the base shaft 6 held by the base shaft holder 1, which may cause such misalignment, will be described in order to prevent misalignment.

As shown in fig. 4 to 6, the self-aligning adapter 40 is configured by assembling the self-aligning bearings 50(50a, 50b), the abutment rings 60(60a, 60b), the coil spring 64, the front-end-side inclined-surface ring 70, the front end cover 80, and the mounting unit 90.

The center bearing 50 constituting the center adjusting adapter 40 is constituted by a plurality of center balls 51 and a retainer 52 which houses the center balls 51 and holds the circumferential position. The center bearing 50 is provided with a distal end side center bearing 50a and a base end side center bearing 50b on the axial distal end side Lf, and is arranged in an orientation symmetrical in the axial direction L with respect to the orientation of the retainer 52.

The self-aligning balls 51 constituting the self-aligning bearings 50(50a, 50b) are steel balls which are in contact with both outer flat surfaces 6a spanning over the corners 6b of the base shaft 6, and in the present embodiment in which the base shaft 6 is formed of a hexagonal cross section, 12 self-aligning balls 51 are provided.

The holder 52 that houses the plurality of aligning balls 51 and holds them at their respective positions is formed of a substantially cylindrical barrel portion lying down, and has an axial through space 56 that penetrates in the axial direction L.

The cylindrical body portion has a housing portion 55 formed at the center in the axial direction L in a single cross section and arranged at equal intervals in the circumferential direction, and a 1 st inclined surface 53 and a 2 nd inclined surface 54 inclined with respect to the axial direction L are formed on both sides in the axial direction L of the housing portion 55.

In addition, the 1 st inclined surface 53 facing the tapered surface 63 of the contact ring 60 described later in the assembled state is formed at an inclination angle corresponding to the tapered surface 63. The 2 nd inclined surface 54 facing the base end tapered surface 911 or the tip end tapered surface 76 is formed at an inclination angle corresponding to the base end tapered surface 911 or the tip end tapered surface 76 of the attachment unit 90, which will be described later.

Further, inside the substantially cylindrical tubular body portion, an axial direction penetrating space 56 penetrating in the axial direction L is formed into a hexagonal shape as viewed from the front, and constitutes a part of a through hole 40a described later.

The housing portion 55 is a cylindrical through hole penetrating the cylindrical main body portion in the radial direction, is formed with a diameter corresponding to the diameter of the housed self-aligning ball 51, and is provided with a stopper (not shown) preventing the housed self-aligning ball 51 from coming off on the inner side in the radial direction.

The housing portion 55 is provided on both sides of each corner of the hexagonal axial through space 56 so as to correspond to 12 center beads 51 between the 1 st inclined surface 53 and the 2 nd inclined surface 54 in the cylindrical main body portion having a substantially hat-shaped cross section and an axial direction L longer than the thickness (radial direction), and 12 in total.

The retainer 52 configured as described above is arranged with the distal-side self-aligning bearing 50a and the proximal-side self-aligning bearing 50b in a symmetrical orientation in the axial direction L.

Specifically, the retainer 52 constituting the distal end side self-aligning bearing 50a is arranged in a direction in which the 1 st inclined surface 53 is the axial base end side Lb and the 2 nd inclined surface 54 is the axial distal end side Lf. On the other hand, the retainer 52 constituting the base end side self-aligning bearing 50b is arranged in a direction in which the 2 nd inclined surface 54 is the base end side Lb in the axial direction and the 1 st inclined surface 53 is the tip end side Lf in the axial direction.

The contact ring 60 is a substantially cylindrical body integrally formed of an outer fitting cylinder portion 61 and an outer fitting cylinder portion 62, the outer fitting cylinder portion 61 is externally fitted to the first inclined surface 53 of the retainer 52 constituting the self-aligning bearing 50, and the outer fitting cylinder portion 62 is externally fitted with the coil spring 64.

Further, a tapered surface 63 that is inclined with respect to the axial distal end side Lf and the radial direction and that flares toward the holder 52 is formed on the inner surface side of the outer cylindrical fitting portion 61. In addition, the tapered surface 63 is inclined at substantially the same angle as the inclination angle of the base end side tapered surface 911 formed on the tapered member 91 in the vertical cross section.

The abutment ring 60 configured as described above is provided with a distal end side abutment ring 60a and a proximal end side abutment ring 60b on the axial distal end side Lf, and is arranged in a symmetrical orientation in the axial direction L.

Specifically, the distal end side contact ring 60a is disposed with the tapered surface 63a facing the axial distal end side Lf, and the proximal end side contact ring 60b is disposed with the tapered surface 63b facing the axial proximal end side Lb.

The coil spring 64 is a so-called coil spring that is biased in the axial direction L, and is externally fitted to the externally fitted cylindrical portion 62 of the abutment ring 60.

The front-end-side inclined-surface ring 70 is attached to the front end of the small-diameter front body portion 12 of the holder 10, and has a substantially annular shape having a through hole 71 penetrating in the axial direction L and having a hexagonal shape when viewed from the front.

Specifically, the front-end-side inclined surface ring 70 has an outer fitting groove portion 73 into which a front end cap 80 described later is fitted, formed on the outer diameter of the axial front end side Lf of the main body tube portion 72 constituting the annular main body. The front-end-side inclined-surface ring 70 has a radially inward projecting portion 74 that projects radially inward to about half of the axial direction L on the axial front end side Lf.

Further, a guide tapered surface 75 that flares toward the axial front end side Lf is formed in the radially inner projection 74. Further, a tapered distal end tapered surface 76 having a larger diameter than the guide tapered surface 75 and expanding in a trumpet shape toward the axial proximal end side Lb is formed on the axial proximal end side Lb of the distal end side inclined surface ring 70.

The distal tapered surface 76 is inclined at an angle of inclination substantially equal to that of a base tapered surface 911 formed on a tapered member 91 described later in the vertical cross section, although the inclination direction is opposite to that of the base tapered surface 911.

As shown in fig. 4 to 8, the front end cover 80 is a cylindrical body that is fitted around a small-diameter cylinder 931 of a housing cylindrical member 93 of the mounting unit 90 described later and is integrated with the mounting unit 90. The distal end cover 80 is a bottomed cylindrical body having an opening at the distal end of the axial distal end side Lf, the opening communicating with an inner through space 81 penetrating in the axial direction L, and the cross section lying down. The opening is formed by a radially inner restricting convex portion 82 that protrudes radially inward.

The mounting unit 90 for mounting the aligning adapter 40 to the distal end of the small diameter front main body portion 12 of the base shaft bracket 1 is configured from the axial base end side Lb side by a tapered member 91, an outer fitting ring 92, and a receiving cylindrical member 93. The taper member 91 has a base end side taper surface 911 and a position adjustment taper surface 912. The outer ring 92 is fitted over the outer peripheral end of the small-diameter front body portion 12 on the axial base end side Lb. The accommodating cylindrical member 93 is fitted to the taper member 91 and the external fitting ring 92 at the distal end of the small-diameter front main body portion 12, and accommodates the self-aligning bearing 50, the contact ring 60, and the coil spring 64 therein.

The cone member 91 has a substantially annular shape having a through hole 914 penetrating in the axial direction L at the center thereof when viewed from the front, and a base end side tapered surface 911 flared toward the axial tip side Lf is formed on the front side of the through hole 914.

Further, a position adjustment tapered surface 912 is formed around the axial base end side Lb of the tapered member 91, in which a through hole 914 is formed, so as to protrude toward the axial base end side Lb and the outer diameter thereof is tapered. An abutment plane 913 is formed radially outward of the axial distal end side Lf of the position adjustment tapered surface 912 of the tapered member 91 so as to face the distal end surface 192 in the attached state.

The position adjustment tapered surface 912 is a tapered convex portion for adjusting the position of the alignment inclined surface 191 in the direction in which the axial direction L coincides. Specifically, in a state of being attached to the base shaft bracket 1, the position adjustment tapered surface 912 faces the alignment inclined surface 191 formed on the front end inner surface side of the small-diameter front body portion 12. The position adjustment tapered surface 912 is formed of a tapered surface having an inclination angle substantially equal to that of the alignment inclined surface 191.

The cone member 91 is made of a magnet capable of magnetically attracting the base shaft holder 1 made of a magnetic metal. Therefore, the tapered member 91 can be magnetically attracted to the tip of the small-diameter front body portion 12 of the base shaft bracket 1.

The cone member 91 is formed of magnets that generate magnetic poles on the radially inner side and the radially outer side, respectively. As long as the plane of the axial base end side Lb of the cone member 91 and the four corners of the radially outer cross section are magnets, the other portions may be made of a magnetic metal.

The outer insert ring 92 is annular and fitted over the axial base end side Lb of the cone member 91 and the tip of the small-diameter front body portion 12, and the end of the axial base end side Lb is formed to have a length abutting against the snap ring 24 fitted in the slip-off preventing hole 17 formed in the outer periphery of the small-diameter front body portion 12.

The outer fitting ring 92, which radially faces the radially outer surface that is one magnetic pole of the tapered member 91, is made of a magnetic metal.

The housing cylindrical member 93 includes a large diameter cylinder 932 on the axial base end side Lb and a small diameter cylinder 931 having a smaller diameter than the large diameter cylinder 932 and protruding toward the axial tip end side Lf than the large diameter cylinder 932, and the housing cylindrical member 93 has through spaces 933, 934 formed therein so as to penetrate in the axial direction L.

The large-diameter tube 932 is configured to externally fit the outer fitting ring 92 and the accommodating tube 93 attached to the distal end of the small-diameter front body 12 of the base shaft bracket 1.

The through space 933 in the small-diameter cylinder 931 is configured to be able to accommodate the self-aligning bearing 50, the contact ring 60, and the coil spring 64 therein in a manner such that the base end side tapered surface 911 of the tapered member 91 is exposed to the through space 933.

Further, an end portion on the axial base end side Lb of the large-diameter tube portion 932 is formed to have a length abutting against the fixed ring 23 fitted to the small-diameter front body portion 12. The cylindrical accommodating member 93, which radially faces the axial distal end side Lf of the radial outer surface that is one magnetic pole of the tapered member 91, is made of a magnetic metal.

The small-diameter cylinder 931 is integrally fitted to the front end cover 80 in an assembled state. The housing tubular member 93 and the distal end cover 80 may be integrally assembled by bonding the housing tubular member 93 and the distal end cover 80. Alternatively, the housing cylindrical member 93 and the front end cap 80 may be integrated by providing a thread on the outer peripheral surface of the small diameter cylinder portion 931, providing a thread groove on the inner surface of the front end cap 80, and screwing the thread of the small diameter cylinder portion 931 into the thread groove of the front end cap 80.

The mounting unit 90 of the self-aligning adapter 40 constituting each element in this way externally fits the external fitting ring 92 to the cone member 91, and mounts the accommodating cylindrical member 93 from the axial distal end side Lf of the cone member 91 and the external fitting ring 92. At this time, the tapered member 91 and the external fitting ring 92 are accommodated in the through space 934 of the accommodating cylindrical member 93.

Further, the external fitting ring 92 and the housing cylindrical member 93 made of magnetic metal are integrated by magnetic attraction with the tapered member 91 made of a magnet. In this assembled state, the proximal tapered surface 911 of the tapered member 91 is exposed toward the axial distal end Lf on the axial proximal end Lb of the through space 933 for accommodating the cylindrical member 93.

The external fitting ring 92 and the accommodating cylindrical member 93 are assembled so as to straddle the outer peripheral side of the distal ends of the tapered member 91 and the small-diameter front body portion 12.

In the self-aligning adapter 40 having the above-described components, the self-aligning ball 51 is first received in the receiving portion 55 of the holder 52, and the self-aligning bearing 50(50a, 50b) is configured.

Further, the coil spring 64 is externally fitted to the externally fitted cylindrical portion 62 of the abutment ring 60.

Specifically, the coil spring 64 is externally fitted from the axial base end side Lb of the externally fitted cylindrical portion 62 of the distal end contact ring 60a disposed toward the axial distal end side Lf with the tapered surface 63a as the axial distal end side Lf. Further, the coil spring 64 is externally fitted from the axial distal end side Lf of the externally fitted cylindrical portion 62 of the base end side abutment ring 60b disposed facing the axial base end side Lb with the tapered surface 63 b. In this case, the distal end side abutment ring 60a and the proximal end side abutment ring 60b may be integrated by an adhesive means such as a double-sided tape having cushioning properties.

In this state, the contact ring 60 is fitted to the outer surface of the retainer 52 constituting the self-aligning bearing 50. Specifically, the tip side contact ring 60a disposed facing the tapered surface 63a as the axial tip side Lf is fitted on the 1 st inclined surface 53 of the retainer 52 of the tip side self-aligning bearing 50a disposed facing the 1 st inclined surface 53 as the axial base end side Lb. Further, the base end side abutting ring 60b disposed facing the base end side Lb with the tapered surface 63b as the axial direction is fitted on the 1 st inclined surface 53 of the retainer 52 of the base end side self-aligning bearing 50b disposed facing the tip end side Lf with the 1 st inclined surface 53 as the axial direction.

Then, the assembled self-aligning bearing 50, the contact ring 60, and the coil spring 64 are accommodated from the axial front end side Lf into the through space 933 for accommodating the cylindrical member 93. At this time, the 2 nd inclined surface 54 of the center-side base bearing 50b is assembled on the axial base end side Lb of the through space 933 so as to face the base end side tapered surface 911 exposed toward the axial tip side Lf.

Further, the front-end-side inclined-surface ring 70 is disposed from the center bearing 50, the contact ring 60, and the axial front end side Lf of the coil spring 64 housed in the through space 933 of the housing cylindrical member 93. Next, the distal end cap 80 is attached from the axial distal end side Lf thereof, and the distal end cap 80 and the housing cylindrical member 93 are integrated, thereby completing the assembly of the aligning adapter 40.

As described above, in the self-aligning adapter 40 assembled in this way, the base end side tapered surface 911 faces the 2 nd inclined surface 54 of the base end side self-aligning bearing 50b on the axial base end side Lb of the through space 933. Further, the 1 st inclined surface 53 of the front end side self-aligning bearing 50a of the self-aligning adapter 40 faces the front end side tapered surface 76 of the front end side inclined surface ring 70.

As shown in fig. 7, the aligning adapter 40 configured as described above has the through hole 71 of the tip-side inclined-surface ring 70, the axial through space 56 of the retainer 52 constituting the aligning bearing 50, and the through hole 914 of the tapered member 91 constituting the mounting unit 90, forming the through hole 40a penetrating in the axial direction L.

As will be described later, the self-aligning adapter 40 thus assembled can be attached to the front end of the base shaft bracket 1.

Specifically, when the center adjusting adapter 40 is mounted to the distal end of the base shaft bracket 1, the position adjustment tapered surface 912 of the tapered member 91 of the mounting unit 90 constituting the center adjusting adapter 40 is fitted to the alignment inclined surface 191 formed on the inner periphery of the distal end of the small-diameter front main body portion 12.

At this time, the position of the aligning adapter 40 with respect to the base shaft bracket 1 can be adjusted so that the axial direction of the aligning adapter 40 coincides with the axial direction L of the base shaft bracket 1 by matching the position adjustment tapered surface 912 with the alignment inclined surface 191.

In the aligning adapter 40 mounted on the small-diameter front main body portion 12 of the base shaft bracket 1 so that the alignment inclined surface 191 and the position adjustment tapered surface 912 are aligned in the axial direction L, as shown in fig. 10 (b), the abutment plane 913 on the axial base end side Lb of the magnet tapered member 91 is in surface contact with the front end surface 192 of the small-diameter front main body portion 12. Further, the inclined surface and the inner surface of the outer fitting ring 92 of the outer fitting cone member 91 on the axial base end side Lb are in surface contact with the inclined distal end surface and the side surface on the radial outer side of the axial distal end side Lf of the small-diameter front body portion 12. Further, the axial base end side Lb of the accommodating cylindrical member 93 externally fitted over the axial tip side Lf of the cone member 91 and the externally fitted ring 92 contacts the fixed ring 23 externally fitted to the small-diameter front body portion 12.

Therefore, as shown in fig. 10 (a), the magnetic circuit including the cone member 91, the external fitting ring 92, the accommodating cylindrical member 93, the small-diameter front main body portion 12, and the fixing ring 23 is configured, whereby the aligning adapter 40 can be firmly fixed to the small-diameter front main body portion 12 of the base shaft bracket 1 in a stable state.

The through hole 40a of the self-aligning adapter 40 attached to the distal end of the holder 10 on the axial distal end side Lf communicates with the base shaft insertion hole 11 of the holder 10.

In this way, the alignment of the base shaft 6 of the rotating jig 5 (base shaft 6) with respect to the alignment adapter 40 attached to the base shaft bracket 1 will be described with reference to fig. 7 to 11.

As shown in fig. 10 (a), when the base shaft 6 is inserted from the axial distal end side Lf into the through hole 40a of the aligning adapter 40 attached to the axial distal end side Lf of the base shaft holder 1, the base end inclined portion 8 of the base shaft 6 abuts against the radially inner side of the aligning ball 51 accommodated in the accommodating portion 55 of the aligning bearing 50.

Then, the base end inclined portion 8 of the base shaft 6 inserted further abuts against the center ball 51. At this time, the self-aligning ball 51 of the front-end self-aligning bearing 50a abuts at least one of the front-end tapered surface 76 of the front-end inclined surface ring 70 and the tapered surface 63a of the front-end abutting ring 60 a. The center ball 51 of the center bearing 50b on the base end side abuts against at least one of the tapered surface 63b and the tapered surface 911 on the base end side of the base end side abutting ring 60 b.

When the center ball 51 passes over the base end inclined portion 8 and comes into contact with the outer flat surface 6a of the base shaft 6 by further insertion of the base shaft 6, as shown in fig. 10 (a), which is an enlarged view of the portion a of fig. 8, the radially outer side of the center ball 51 of the distal end side center bearing 50a reliably comes into contact with both the distal end side tapered surface 76 of the distal end side inclined surface ring 70 and the tapered surface 63a of the distal end side contact ring 60 a. Further, the radially outer side of the center ball 51 of the base end side center bearing 50b reliably abuts both the tapered surface 63b and the base end side tapered surface 911 of the base end side abutting ring 60 b.

At this time, since the distal-side tapered surface 76 is fixed to the holder body 10, the distal-side abutment ring 60a constituting the tapered surface 63a moves toward the axial distal side Lf against the urging force of the coil spring 64. Further, the axial distal end side Lf of the center ball 51 of the distal end side center bearing 50a is in contact with the distal end side tapered surface 76 on the radially outer side. The axial base end side Lb abuts on the tapered surface 63 a.

Thus, the distal-side tapered surface 76 and the tapered surface 63a that contact the radially outer side of the center ball 51 of the distal-side center bearing 50a are inclined in opposite directions with respect to the axial direction L. Therefore, the radially outer side of the center-adjusting ball 51 is restricted by the tip-side tapered surface 76 and the tapered surface 63a having a splayed longitudinal section.

Further, the tapered surface 63a that regulates the splaying of the radially outer side of the center ball 51 of the front end side center bearing 50a is urged toward the axial front end side Lf by the coil spring 64. Therefore, as shown by the arrow in the enlarged view of the portion a in fig. 9 (b), the biasing force of the coil spring 64 via the tapered surface 63a acts on the radially inner side of the center ball 51 of the distal end side center bearing 50 a.

Similarly, the base end side tapered surface 911 is a part of the tapered member 91 that is aligned by the position adjustment tapered surface 912 abutting against the alignment inclined surface 191 at the distal end of the holder 10. Therefore, the base end side abutting ring 60b constituting the tapered surface 63b moves toward the axial base end side Lb against the biasing force of the coil spring 64. Further, the axial base end side Lb of the center ball 51 radially outwardly abuts the base end side tapered surface 911, and the axial tip end side Lf abuts the tapered surface 63 b.

Thus, the base-side tapered surface 911 and the tapered surface 63b that contact the radially outer side of the self-aligning ball 51 of the base-side self-aligning bearing 50b are inclined in opposite directions with respect to the axial direction L. Therefore, the radially outer side of the self-aligning ball 51 is restricted by the base end side tapered surface 911 and the tapered surface 63b having the splayed vertical cross section.

The tapered surface 63b that regulates the splaying outward in the radial direction of the aligning ball 51 is biased toward the axial base end side Lb by the coil spring 64. Therefore, the biasing force of the coil spring 64 via the tapered surface 63b acts on the center ball 51 of the base end side center bearing 50b toward the radially inner side (see an arrow in the enlarged view of the portion a of fig. 9 (b)).

As shown in fig. 9, the spherical balls 51(51a, 51b) of the spherical bearings 50a, 50b, on which the biasing force of the coil spring 64 acts radially outward, are brought into contact with the outer flat surfaces 6a on both sides across the corner portion 6b of the base shaft 6 by the retainer 52. Therefore, the base shaft 6 can be aligned by the plurality of aligning balls 51 abutting on both sides of the corner portion 6 b.

Next, the aligning adapter 40X and the base shaft bracket 1 to which the aligning adapter 40X is attached according to embodiment 2 will be described with reference to fig. 11 to 20.

In the following description of the center adjusting adapter 40X and the base shaft bracket 1 to which the center adjusting adapter 40X is attached according to embodiment 2, the same components as those of the center adjusting adapter 40 and the base shaft bracket 1 are denoted by the same reference numerals, and detailed description thereof will be omitted.

Fig. 11 is a front view of an electric power tool K in which a center adjusting adapter 40X according to embodiment 2 is attached to a base shaft holder 1, fig. 12 is a perspective view of the base shaft holder 1 in a state in which the center adjusting adapter 40X is attached, and fig. 13 is a perspective view of the base shaft holder 1 before the center adjusting adapter 40X is attached.

Fig. 14 is an exploded explanatory view showing the front, back, side, or cross section of each component of the aligning adapter 40X and the base shaft holder 1.

In detail, the base shaft bracket 1, the radially outer member 94, the ring magnet 95, the abutment ring 60, the aligning balls 51, the cage 52, and the coil spring 64 are shown in a longitudinal sectional view and a front view. In addition, the cone-receiving cylindrical member 96, the front-end-side inclined-surface ring 70, and the front end cap 80X are shown in longitudinal sectional view and rear view.

The center ball 51 and the retainer 52 constituting the center bearing 50(50a, 50b) are cross-sectional views a-a in front views of the center ball 51 and the retainer 52, which are cross-sections of the annular retainer 52 passing through the housing portion 55.

Fig. 15 is an exploded perspective view of each component of the center-adjusting adapter 40X as viewed from the front side, fig. 16 is an exploded perspective view of each component of the center-adjusting adapter 40X as viewed from the back side, and fig. 17 is a perspective view of the center-adjusting adapter 40X. In fig. 17, the center ball 51 and the coil spring 64 are not shown, and a part of the center adaptor 40X on the near side is cut away to be shown.

Fig. 18 shows a longitudinal sectional view of the base shaft holder 1 to which the self-aligning adapter 40X is attached, fig. 19 shows an explanatory view of the alignment by the self-aligning adapter 40X, and fig. 20 shows an explanatory view of the base shaft holder 1 to which the self-aligning adapter 40X is attached in the longitudinal sectional view.

Specifically, fig. 19 (a) is a c-c sectional view in fig. 18, and fig. 19 (b) is an enlarged view of a portion a in fig. 19 (a). Fig. 20 (a) is an enlarged view of a portion a in fig. 18 in a state where the base shaft holder 1 of the center adjusting adapter 40X is attached to the distal end of the small-diameter front main body portion 12 of the base shaft holder 1, and fig. 20 (b) is an enlarged view of a portion a in a state before the center adjusting adapter 40X is attached.

Specifically, the base shaft bracket 1, the self-aligning bearing 50, the contact ring 60, the coil spring 64, and the front-end-side inclined-surface ring 70 have the same configurations as those of the above-described self-aligning adapter 40, and therefore, descriptions thereof are omitted. The front end cover 80X and the attachment unit 90X having different structures will be described.

As shown in fig. 14 to 18, the distal end cap 80X is a cylindrical body that is fitted over a cylindrical body portion 961 of a tapered housing cylindrical member 96 of a mounting unit 90X described later and is integrated with the mounting unit 90X. The distal end cover 80X is a bottomed cylindrical body having an opening at the distal end of the axial distal end side Lf, the opening communicating with the through space 81X penetrating in the axial direction L.

The opening is formed by a radially inner restricting convex portion 82X that protrudes radially inward. Further, a screw groove 83 to be screwed with a screw thread 967 formed on the outer peripheral surface of the tapered accommodation tubular member 96 is provided on the inner surface of the distal end side Lf in the axial direction of the distal end cap 80X.

The mounting unit 90X for mounting the center adjusting adapter 40X to the tip of the small-diameter front body portion 12 of the base shaft bracket 1 is configured from a substantially cylindrical radially outer member 94, a ring-shaped magnet 95 formed in an annular shape, and a tapered accommodating cylindrical member 96 from the axial base end side Lb side.

The radially outer member 94 is externally fitted to the tip of the axially tip side Lf of the small-diameter front body portion 12, and the tapered housing cylindrical member 96 houses the self-aligning bearing 50, the contact ring 60, and the coil spring 64 therein.

The radially outer member 94 is a substantially cylindrical member that spans the outer periphery of the tip of the small-diameter front barrel 12 and the outer periphery of the axial base end side Lb of a tapered accommodating cylindrical member 96 disposed at the tip of the small-diameter front barrel 12. The outer diameter member 94 is a substantially cylindrical shape formed by integrating a base end large diameter portion 941, which is inserted between the outer periphery of the distal end of the small diameter front body portion 12 and the inner surface of the sleeve 30, and a distal end portion 942, which is disposed radially outward of the axial base end side Lb of the tapered accommodating cylindrical member 96. The radially outer member 94 is provided with a thread groove 943 on the inner surface thereof, which is screwed to a thread 967 formed on the outer surface of the tapered cylindrical housing member 96. Further, the radially outer member 94 is made of a magnetic metal.

The ring magnet 95 is a ring magnet that generates magnetic poles on both sides in the axial direction L, and has a contact flat surface 951 facing the distal end surface 192 of the small-diameter front body portion 12.

The tapered housing tubular member 96 is formed of a substantially annular tubular body portion 961 having a bottom, the tubular body portion 961 penetrating in the axial direction L at the center in front view and having a through housing space 963, and a base end side tapered surface 964 expanding in a trumpet shape is formed on the axial base end side Lb of the through housing space 963 in the tubular body portion 961.

Further, a position adjustment tapered surface 965 is formed on the axial direction base end side Lb of the tapered housing tubular member 96, and the position adjustment tapered surface 965 adjusts the axial direction L of the alignment adapter 40X with respect to the axial direction L of the base shaft holder 1 by the aligning inclined surface 191 of the base shaft holder 1.

The periphery of the position adjustment tapered surface 965 that penetrates the housing space 963 protrudes toward the axial base end side Lb, and the outer diameter of the position adjustment tapered surface 965 is tapered.

The position adjustment tapered surface 965 is a tapered convex portion for adjusting the position of the alignment inclined surface 191 in the direction in which the axial direction L coincides. Specifically, in the state of being attached to the base shaft holder 1, the position adjustment tapered surface 965 faces the alignment inclined surface 191 formed on the front end inner surface side of the small-diameter front body portion 12. The position adjustment tapered surface 965 is formed of a tapered surface having an inclination angle substantially equal to that of the alignment inclined surface 191.

Further, an insertion groove 966 into which the ring magnet 95 is inserted is formed on the outer peripheral side of the position adjustment tapered surface 965. A thread 967 is formed on the outer peripheral surface, and the thread 967 is screwed into the thread groove 943 of the radially outer member 94 or the thread groove 83 of the distal end cap 80X.

The through housing space 963 in the cylindrical body portion 961 is configured to be able to house the self-aligning bearing 50, the contact ring 60, and the coil spring 64 therein such that the base end side tapered surface 964 of the tapered housing cylindrical member 96 is exposed in the through space 933.

The cone-shaped housing cylindrical member 96 configured as described above is integrated by fitting the ring magnet 95 into the fitting groove 966, and the cone-shaped housing cylindrical member 96 is made of a magnetic metal magnetized by the magnetic force of the ring magnet 95.

The mounting unit 90X thus constituting each element can mount the aligning adapter 40X to the tip of the small-diameter front main body portion 12.

Specifically, the attachment unit 90X is assembled by screwing the thread groove 943 of the radially outer member 94 and the thread ridge 967 from the axial base end side Lb of the tapered cylindrical accommodation member 96 in which the ring magnet 95 is fitted in the fitting groove 966. The screwing amount of the thread groove 943 and the thread ridge 967 at this time can be adjusted according to the shape of the base shaft holder 1 to which the aligning adapter 40X is attached.

As described in the description of the aligning adapter 40, the aligning bearing 50, the contact ring 60, and the coil spring 64 assembled together are housed in the through housing space 963 of the mounting unit 90X assembled in this manner.

At this time, the 2 nd inclined surface 54 of the center-side-adjusting base bearing 50b is assembled so as to face the base-side tapered surface 964 exposed toward the axial distal end Lf on the axial base-side Lb penetrating the housing space 963.

Further, the front-end-side inclined-surface ring 70 is disposed from the center-adjusting bearing 50, the contact ring 60, and the axial front end side Lf of the coil spring 64 housed in the through housing space 963 of the tapered housing tubular member 96. Then, the front end cover 80X is attached from the axial front end side Lf thereof. Further, the screw groove 83 is screwed with the screw thread 967 of the tapered housing cylindrical member 96, and the distal end cap 80X and the tapered housing cylindrical member 96 are integrated, thereby completing the assembly of the aligning adapter 40X.

As described above, in the self-aligning adapter 40X assembled in this way, the base end side tapered surface 964 and the 2 nd inclined surface 54 of the base end side self-aligning bearing 50b face each other on the axial base end side Lb penetrating the housing space 963. The 1 st inclined surface 53 of the front-end self-aligning bearing 50a faces the front-end tapered surface 76 of the front-end inclined surface ring 70.

As shown in fig. 17, the self-aligning adapter 40X configured as described above has a through hole 40Xa penetrating in the axial direction L formed by the through hole 71 of the tip-side inclined-surface ring 70, the axial through space 56 of the retainer 52 constituting the self-aligning bearing 50, and the through housing space 963 of the tapered housing cylindrical member 96 constituting the mounting unit 90X.

In addition, in a state where the aligning adapter 40X is attached to the distal end of the small-diameter front main body portion 12, the end portion on the axial base end side Lb of the base end large diameter portion 941 of the diameter outer member 94 abuts against the fixed ring 23 of the base shaft bracket 1 from the axial distal end side Lf, and the engagement groove 18 abuts against the inner surface of the base end large diameter portion 941.

The base end side tapered surface 964 of the aligning adapter 40X attached to the tip of the small-diameter front main body portion 12 functions instead of the base end side tapered surface 911 of the aligning adapter 40. The position adjustment tapered surface 965 functions in place of the position adjustment tapered surface 912. Further, the abutment flat surface 951 of the ring magnet 95 functions in place of the abutment flat surface 913. Therefore, as with the aligning adapter 40, the front end of the small-diameter front main body portion 12 can be firmly fixed in a stable state, and the aligning function can be performed.

The aligning adapter 40(40X) which is attached to the base shaft bracket 1 in this way and aligns the base shaft 6 held by the base shaft bracket 1 is provided with the aligning bearings 50(50a, 50b) which align the base shaft 6 of the rotation jig 5 inserted through the through hole 40a (40Xa) by abutting the aligning bearing 50 and the attachment unit 90(90X) which inserts the aligning bearing 50(50a, 50b) from the axial front end side Lf and attaches the aligning bearing 50 to the front end position of the axial front end side Lf of the bracket body 10 constituting the base shaft bracket 1 which holds the base shaft 6, so that the base shaft 6 held by the base shaft bracket 1 can be aligned to prevent the core shift when the rotation jig 5 rotates.

Specifically, by attaching the aligning adapter 40(40X) to the base shaft holder 1 holding the base shaft 6, the base shaft 6 held by the base shaft holder 1 can be aligned by the aligning bearings 50(50a, 50b), and core misalignment when the rotating jig 5 rotates can be prevented.

When the base shaft 6 thus aligned by the aligning adapter 40(40X) is inserted into the base shaft insertion hole 11 communicating with the through hole 40a (40Xa) of the aligning adapter 40(40X), the base end inclined portion 8, which is the base end portion of the base shaft 6, is aligned by the tapered space 111 supported at the tip end in the base shaft insertion hole 11 of the base shaft bracket 1, as described above. The center is also adjusted by the center adjusting bearing 50 of the center adjusting adapter 40(40X) attached to the axial front end side Lf of the base shaft bracket 1. Therefore, compared to the case where the center is adjusted inside the sleeve 30 of the base shaft holder 1, for example, the distance from the tapered space 111 supported at the tip end in the base shaft insertion hole 11 of the base shaft holder 1 to the center adjusting bearings 50(50a, 50b) adjusted in the center adjusting adapter 40(40X) becomes longer, and the center can be adjusted with higher accuracy.

Further, the mounting unit 90(90X) is provided with a position adjustment tapered surface 912(965) which performs position adjustment by a positioning inclined surface 191 formed at the tip of the axial tip side Lf of the base shaft insertion hole 11 of the holder body 10 and having a diameter enlarged toward the tip so that the axial direction L of the self-aligning bearings 50(50a, 50b) coincides with the axial direction L of the holder body 10. Therefore, the aligning adapter 40(40X) can be easily attached so that the axial direction L coincides with the holder body 10.

Specifically, when the position adjustment tapered surfaces 912 and 965 provided in the tapered member 91 (the tapered housing tubular member 96) are matched with the alignment inclined surface 191 formed at the distal end of the base shaft insertion hole 11 of the holder 10, the position is adjusted so that the axial direction L of the aligning adapter 40(40X) coincides with the axial direction L of the holder 10. Further, the aligning adapter 40(40X) can be easily attached so that the axial direction L coincides with the holder body 10. Therefore, the base shaft 6 can be aligned with respect to the base shaft holder 1 with high accuracy.

Further, in a state where the base shaft 6 is inserted into the base shaft insertion hole 11 via the aligning adapter 40(40X) attached to the holder body 10 so as to be aligned in the axial direction L and the base shaft 6 is held by the base shaft holder 1, the aligning adapter 40(40X) is slightly rotated with respect to the holder body 10 around the axial direction L. Thereby, the position adjustment tapered surfaces 912(965) of the aligning adapter 40(40X) rotate relative to the alignment inclined surface 191 of the holder 10. Then, the axial direction L of the holder body 10 and the axial direction L of the aligning adapter 40(40X) are adjusted to each other. Therefore, for example, tolerance due to machining or assembly can be absorbed, and the accuracy of the position adjustment in the axial direction L of the holder body 10 and the aligning adapter 40(40X) can be further improved.

At least a part of the cone member 91 (the cone-shaped housing cylindrical member 96) of the attachment unit 90(90X) is constituted by a magnet magnetically attracted to the holder body 10 which is a magnetic metal. Therefore, the aligning adapter 40(40X) can be easily attached to and detached from the holder body 10, which is a magnetic metal.

Specifically, for example, as compared with a case where a screw mechanism such as a screw thread is provided in the mounting unit of the aligning adapter and the mounting unit is screwed into the holder body 10 to be attached and detached, the aligning adapter 40(40X) can be easily attached and detached to and from the holder body 10 by the magnetic force of the magnet constituting at least a part of the cone member 91 (the ring magnet 95 attached to the cone-shaped housing cylindrical member 96).

Even if the screw mechanism such as a screw thread is provided in the mounting unit 90(90X) of the aligning adapter 40(40X) and detachably screw-mounted to the holder body 10 as described above, the screw mechanism needs to be provided in the holder body 10 when the screw mechanism is not provided in the holder body 10 of the base shaft holder 1 to be used. On the other hand, the aligning adapter 40(40X) is attached to the holder body 10 by the magnetic force of the magnet (the ring magnet 95 attached to the tapered housing cylindrical member 96) constituting at least a part of the tapered member 91. Therefore, if the holder body 10 is made of magnetic metal, the aligning adapter 40(40X) can be easily attached to and detached from the base shaft holder 1 to be used without any processing.

Further, the tapered member 91 (the ring magnet 95 attached to the tapered housing tubular member 96) made of a magnet is provided with a contact flat surface 913(951) facing the distal end surface 192 of the holder body 10. Further, the stent further includes an outer collar 92 and a housing cylindrical member 93 (radially outer member 94), and the outer collar 92 and the housing cylindrical member 93 (radially outer member 94) are made of a magnetic metal and extend radially outward across the cone member 91 (tapered housing cylindrical member 96) and the stent body 10. Therefore, the aligning adapter 40(40X) can be easily attached to and detached from the holder 10 by magnetically attracting the cone member 91 (the cone-shaped housing cylindrical member 96) to the holder 10.

Further, an outer fitting ring 92 and a receiving cylindrical member 93 (radially outer member 94) are provided so as to extend radially outward across the cone member 91 (cone receiving cylindrical member 96) and the stent body 10. Therefore, the magnetic circuit can be constituted by the tapered member 91 (tapered housing cylindrical member 96), the holder body 10, the outer insert ring 92, and the housing cylindrical member 93 (radially outer member 94). Therefore, the mounting unit 90(90X) can be firmly mounted on the holder body 10, compared to mounting using only magnetic attraction.

Further, the abutment flat surfaces 913(951) of the tapered member 91 (the ring magnet 95 attached to the tapered housing tubular member 96) made of a magnet are opposed to the distal end surface 192 and magnetically attracted to the holder body 10. Thus, the contact area between the tapered member 91 (the tapered housing tubular member 96) and the holder body 10 is enlarged. Therefore, the stability of the mounting state can be improved, and more firm fixing can be achieved.

The magnetic circuit is constituted by the tapered member 91 (tapered housing cylindrical member 96), the holder 10, the outer insert ring 92, and the housing cylindrical member 93 (radially outer member 94). Therefore, the base shaft 6 made of a magnetic metal is not accidentally attracted, and operability can be improved.

Further, since the self-aligning bearings 50(50a, 50b) are provided with the self-aligning balls 51 which are abutted from at least three directions of the base shaft 6 inserted into the through hole 40a (40Xa) to perform the alignment, the self-aligning balls 51 can be abutted from at least three directions to perform the alignment with high accuracy.

Further, the rotation jig is provided with a tilt member (70, 91, 96) and a coil spring (64), the tilt member (70, 91, 96) has an axial direction inclined surface (76, 911, 964) inclined with respect to the axial direction L in a direction of guiding the abutted center-adjusting ball (51) to the inside in the radial direction of the through hole (40 a) (40Xa), the coil spring (64) biases the axial direction inclined surface (76, 911, 964), and the axial direction inclined surface (76, 911, 964) is inclined with respect to the axial direction L in a direction of guiding the abutted center-adjusting ball (51) to the inside in the radial direction of the through hole (40 a) (40Xa), so that the base shaft (6) held by the base shaft bracket (1) can be aligned to further prevent the core shift when the rotation jig (5) rotates.

Specifically, the self-aligning ball 51 urged by the coil spring 64 abuts against the axial inclined surface (76, 911, 964) provided on the inclined member (70, 91, 96). The center ball 51 moves in the radial center direction by the axially inclined surface (76, 911, 964), or the biasing force of the coil spring 64 acts in the radial center direction via the center ball 51. Therefore, the base shaft 6 inserted into the base shaft insertion hole 11 of the holder 10 can be aligned by coming into contact with the base shaft in at least three directions. Therefore, the core shift when the rotation jig 5 rotates can be prevented by aligning the base shaft 6 held by the base shaft holder 1.

In addition, the center ball 51 is provided with: a front end side self-aligning bearing 50a that aligns the base shaft 6 on the axial front end side Lf in the axial direction L; and a base end side self-aligning bearing 50b for aligning the base shaft 6 on the axial base end side Lb in the axial direction L, and provided with: a tip-side tapered surface 76 that guides the tip-side self-aligning bearing 50a that is in contact therewith radially inward; and a base end side tapered surface 911(964) that guides the base end side self-aligning bearing 50b in contact therewith radially inward, and includes: a tip-side inclined surface ring 70 having a tip-side tapered surface 76; and a cone member 91 (a cone-shaped housing cylindrical member 96) having a base end side tapered surface 911(964), the coil spring 64 being disposed between the tip side self-aligning bearing 50a and the base end side self-aligning bearing 50b in the axial direction L and urging the tip side self-aligning bearing 50a and the base end side self-aligning bearing 50b in a direction separating in the axial direction L, so that the tip side self-aligning bearing 50a and the base end side self-aligning bearing 50b respectively align the base shaft 6, that is, align the base shaft 6 at two locations in the axial direction L, and thus the base shaft 6 can be aligned with higher accuracy.

Further, as the center balls 51, a center ball 51a that centers the base shaft 6 on the axial distal end side Lf in the axial direction L and a center ball 51b that centers the base shaft 6 on the axial base end side Lb in the axial direction L are provided. Further, a distal-side tapered surface 76 and a base-side tapered surface 911(964) are provided, the distal-side tapered surface 76 abutting against the center bead 51a and guiding the center bead 51a radially inward, and the base-side tapered surface 911(964) abutting against the center bead 51b and guiding the center bead 51b radially inward. Therefore, the coil spring 64 biases in the direction in which the distal end side self-aligning bearing 50a and the distal end side tapered surface 76 approach each other, and biases in the direction in which the base end side self-aligning bearing 50b and the base end side tapered surface 911(964) approach each other.

Further, since the distal end side contact ring 60a and the base end side contact ring 60b are provided, the distal end side contact ring 60a is disposed between the distal end side self-aligning bearing 50a and the coil spring 64 and has the tapered surface 63a which is in contact with the distal end side self-aligning bearing 50a, the tapered surface 63a is inclined with respect to the axial direction L in the direction opposite to the distal end side tapered surface 76, the base end side contact ring 60b is disposed between the base end side self-aligning bearing 50b and the coil spring 64 and has the tapered surface 63b which is in contact with the base end side self-aligning bearing 50b, and the tapered surface 63b is inclined with respect to the axial direction L in the direction opposite to the base end side tapered surface 911(964), the biasing force of the coil spring 64 can be decomposed into the direction in which the distal end side self-aligning bearing 50a is biased toward the distal end side tapered surface 76 and the direction in which the distal end side self-aligning bearing 50a is in contact with the base shaft 6, that is the radial direction, and the direction in which the The base shaft 6 is urged in a radial direction. Therefore, even if a force acting radially outward from the driven axial base end side Lb toward the distal end side self-aligning bearing 50a or the base end side self-aligning bearing 50b can be resisted by the biasing force of the coil spring 64.

The distal-side tapered surface 76 and the tapered surface 63a regulate the radially outer side of the distal-side self-aligning bearing 50a in the aligning state in contact with the base shaft 6 so as to form a splay shape in the axial L cross section in a state where the biasing force of the coil spring 64 is applied. The base end side tapered surfaces 911(964) and the tapered surface 63b regulate the radial outer sides of the base end side self-aligning bearing 50b in the aligning state so as to form a figure-eight shape in the axial L cross section in a state where the biasing force of the coil spring 64 is applied. Therefore, even if a force directed radially outward acts on the centering beads 51 from the driven axial base end side Lb, the force can be resisted by the biasing force of the coil spring 64.

Therefore, the core shift when the rotation jig 5 rotates can be reliably prevented by aligning the base shaft 6 held by the base shaft holder 1.

The annular retainer 52 has an axial through space 56 that holds a circumferential interval between the plurality of aligning balls 51 and that penetrates in the axial direction L. The axial through space 56 forms a part of the through hole 40a (40 Xa). Therefore, the plurality of aligning balls 51 held by the holder 52 at intervals in the circumferential direction are in contact with the outer surface so as to sandwich at least three corners of the base shaft 6 in the direction. Further, the plurality of aligning balls 51 held by the holder 52 at intervals in the circumferential direction are in contact with the outer surface so as to sandwich at least three corners of the base shaft 6 in the circumferential direction, and the base shaft 6 can be aligned and held with high accuracy in the through hole 40a (40Xa) which is a part of the axial through space 56 of the holder 52. That is, the center ball 51 centers the base shaft 6 held by the base shaft holder 1, and thus core displacement during rotation of the rotary jig 5 can be more reliably prevented.

Further, by holding a plurality of the aligning balls 51 on the annular retainer 52, the aligning bearing 50 can be configured while keeping the circumferential interval between the aligning balls 51, and the assembling property of the aligning adapter 40(40X) having the aligning bearing 50 can be improved.

The electric tool K, which has the motor M and the rotation transmission means for transmitting the rotation force of the motor M on the axial center, is capable of rotating the rotation jig 5 without causing the core misalignment by aligning the base shaft 6 and assembling the aligning adapter 40(40X) to the base shaft holder 1.

In the correspondence between the structure of the present invention and the above-described embodiments, the through-holes of the present invention correspond to the through-holes 40a and 40Xa,

in the same way as described below, the following,

the rotating jig corresponds to the rotating jig 5,

the base shaft corresponds to the base shaft 6,

the aligning unit corresponds to the aligning bearings 50(50a, 50b),

the front end side corresponds to the axial front end side Lf,

the base shaft bracket corresponds to the base shaft bracket 1,

the main body of the bracket corresponds to the bracket body 10,

the mounting parts correspond to the mounting units 90, 90X,

the mounting type aligning device corresponds to the aligning adapters 40, 40X,

the front end cone surface corresponds to the corresponding inclined surface 191,

the axial direction corresponds to the axial direction L,

the position adjusting part adjusts the conical surfaces 912 and 965 correspondingly,

the front face corresponds to the front face 192,

the opposing portions abut against the flat surfaces 913 and 951,

the radially outer member corresponds to the outer insert ring 92 and the receiving cylindrical member 93 or the radially outer member 94,

the aligning member corresponds to the aligning ball 51,

the axially inclined surfaces correspond to the tip end side tapered surface 76 and the base end side tapered surfaces 911 and 964,

the tilting member corresponds to the front end side bevel ring 70, the tapered member 91 or the tapered receiving cylindrical member 96,

the urging unit corresponds to the coil spring 64,

the front end side aligning member corresponds to the front end side aligning bearing 50a,

the base end side corresponds to the axial base end side Lb,

the base end side aligning member corresponds to the base end side aligning bearing 50b,

the front end side inclined surface corresponds to the front end side tapered surface 76,

the base end side inclined surface corresponds to the base end side tapered surfaces 911 and 964,

the front-end side inclined member corresponds to the front-end side inclined-surface ring 70,

the base end side inclined member corresponds to the taper member 91 or the taper receiving cylindrical member 96,

the axial through hole corresponds to the axial through space 56,

the holding member corresponds to the holding frame 52,

the driving device corresponds to the motor M,

the rotation transmission unit corresponds to the rotation transmission mechanism,

the electric power tool corresponds to the electric power tool K, but the present invention is not limited to the configuration of the above-described embodiment, and many embodiments can be obtained.

For example, the base shaft holder 1 may be attached not only to the electric power tool K but also to a rotary electric power tool such as a vibration drill or an electric screwdriver, and may be attached not only to an electric power tool but also to a tool using a manual or internal combustion engine as a driving source.

The rotary jig 5 may be a rotary drill, a cross or a straight screwdriver bit, and the base shaft 6 of the rotary jig 5 is also referred to as a tool shank. In addition to the hexagonal cross section, the base shaft 6 can be reliably aligned by the base shaft holder 1 even in various cross-sectional shapes such as a polygonal cross section such as a rectangular cross section and a circular cross section.

Instead of the center-adjusting ball 51 that moves in the radial center direction and comes into contact with the outer flat surface 6a of the base shaft 6 to perform the center adjustment, a means that comes into contact with the outer flat surface 6a of the base shaft 6 by deformation such as extension in the radial center direction may be used. Alternatively, for example, the outer circumferential surface of the base shaft 6 may be formed of one member such as an elastic ring that is fitted to the outside so as to bias the outer circumferential surface in the radial inward direction.

For example, instead of the center ball 51, a rolling member such as a plurality of rollers may be provided, which has a rotation axis perpendicular to the axial direction L, is rotatable in the axial direction L, and is configured to abut against the outer flat surface 6a of the base shaft 6. Further, the rolling elements such as rollers or the aligning balls 51 may be arranged on a rubber ring, and the rolling elements such as rollers or the aligning balls 51 may be urged radially inward by the urging force of the rubber ring to align the base shaft 6.

In the base shaft bracket 1, 12 aligning balls 51 are arranged at equal intervals in the circumferential direction, and are aligned by being in contact with an outer flat surface 6a that spans a corner portion 6b of the base shaft 6 having a hexagonal cross section. On the other hand, the 6 center-adjusting balls 51 may be aligned by being brought into contact with the outer flat surface 6a of the 3 corner portions 6b at equal intervals in the circumferential direction out of the 6 corner portions 6b of the base shaft 6.

In the above description, the base end portion of the base shaft insertion hole 11 has the tapered space 111, and the base end inclined portion 8 of the base shaft 6 is aligned by the tapered space 111. On the other hand, instead of the tapered space 111, the base shaft insertion hole 11 may be formed of another member disposed at the hole base end portion thereof. Alternatively, the center of gravity may be supported by the apex portion 8a of the base end inclined portion 8 or the vicinity of the apex portion 8 a. Further, the top portion 8a of the base end inclined portion 8 may not be center-supported.

In the self-aligning adapter 40(40X), the distal tapered surface 76 and the proximal tapered surface 911(964) are inclined in opposite directions. In contrast, the distal-side tapered surface 76 and the base-side tapered surface 911(964) in the self-aligning adapter 40(40X) may be inclined in the same direction. In this case, 2 coil springs 64 are provided to bias the distal end side self-aligning bearing 50a toward the distal end side tapered surface 76 and bias the base end side self-aligning bearing 50b toward the base end side tapered surface 911 inclined in the same direction as the distal end side tapered surface 76, thereby aligning the bearings.

The tip-side tapered surface 76 and the base-side tapered surface 911(964) of the self-aligning adapter 40(40X) are inclined at the same inclination angle. In contrast, the inclination angles of the distal-side tapered surface 76 and the base-side tapered surface 911(964) in the self-aligning adapter 40(40X) may be different. In this case, the degree of alignment of the distal side self-aligning bearing 50a and the proximal side self-aligning bearing 50b may be changed.

Description of the reference symbols

1: a base shaft support; 5: rotating the jig; 6: a base shaft; 10: a stent body; 40. 40X: a centering adapter; 40a, 40 Xa: a through hole; 50: a self-aligning bearing; 50 a: a front end side aligning bearing; 50 b: a base end side aligning bearing; 51: a center-aligning ball; 52: a holder; 56: an axial through space; 64: a coil spring; 70: a front end side inclined plane ring; 76: a front end side conical surface; 90. 90X: a mounting unit; 91: a cone member; 92: an outer embedded ring; 93: a housing cylindrical member; 94: an outer diameter member; 96: a conical housing cylindrical member; 191: aligning the inclined plane; 192: a front end face; 911. 964: a base end side conical surface; 912. 965: a position adjusting conical surface; 913. 951: an abutment plane; l: axial direction; lb: an axial base end side; lf: an axial front end side; m: a motor; k: provided is a power tool.