阅读说明：本技术 带减速机构的马达 (Motor with speed reducing mechanism ) 是由 青山知弘 足立勇 安念哲史 于 2018-12-18 设计创作，主要内容包括：带减速机构的马达包括马达部、减速机构、运动转换机构以及外壳。运动转换机构将减速机构的旋转运动转换为往复旋转运动并向输出轴传递。减速机构具有蜗杆、第一齿轮以及第二齿轮。蜗杆设于马达部的旋转轴。第一齿轮传递蜗杆的旋转并且以第一轴为中心进行旋转。第二齿轮传递有第一齿轮的旋转并且以第二轴为中心进行旋转。运动转换机构具有转动构件和杆。转动构件具有扇区齿轮并且以第一轴的轴线为中心进行转动。杆将第二齿轮和转动构件连结。输出轴具有与扇区齿轮啮合的输出齿轮。(The motor with a speed reduction mechanism includes a motor portion, a speed reduction mechanism, a motion conversion mechanism, and a housing. The motion conversion mechanism converts the rotational motion of the reduction mechanism into a reciprocating rotational motion and transmits the reciprocating rotational motion to the output shaft. The reduction mechanism has a worm, a first gear, and a second gear. The worm is provided on the rotation axis of the motor unit. The first gear transmits rotation of the worm and rotates about the first shaft. The second gear transmits the rotation of the first gear and rotates about the second shaft. The motion conversion mechanism has a rotating member and a lever. The rotating member has a sector gear and rotates about the axis of the first shaft. The lever couples the second gear and the rotating member. The output shaft has an output gear that meshes with the sector gear.)

1. A motor with a reduction mechanism, comprising:

a motor section;

a speed reduction mechanism that reduces the rotation of the rotating body of the motor unit;

a motion conversion mechanism that converts the rotational motion of the reduction mechanism into a reciprocating rotational motion and transmits the reciprocating rotational motion to an output shaft; and

a housing that houses the speed reduction mechanism and the motion conversion mechanism,

the speed reduction mechanism includes: a worm provided on a rotation shaft of the motor unit; a first gear that transmits rotation of the worm and rotates about a first shaft provided in the housing; and a second gear that transmits rotation of the first gear and rotates around a second shaft provided in the housing at a position different from the first shaft,

the motion conversion mechanism includes: a rotating member having a sector gear and rotating about an axis of the first shaft; and a lever coupling the second gear and the rotating member,

the output shaft has an output gear that meshes with the sector gear.

2. The motor with a reduction mechanism according to claim 1,

the sector gear is provided at an end portion of the rotating member on the opposite side to the lever.

3. The motor with a reduction mechanism according to claim 1 or 2,

the rotating member is pivotally supported by any one member of a shaft member shared with the first gear, a concave portion or a convex portion provided on an end surface of the first gear, and a shaft member protruding from an end surface of the first gear.

4. A motor with a reduction mechanism according to any one of claims 1 to 3,

the lever is provided so as to be at least partially sandwiched by the rotating member and the second gear, or the lever is provided on the same side with respect to the rotating member and the second gear in a direction along the axis of the first shaft or the second shaft.

5. A motor with a reduction mechanism according to any one of claims 1 to 4,

the first shaft is disposed on one side with respect to an axis of the rotary shaft when viewed from an axial direction of the output shaft,

the second shaft is disposed on the other side with respect to the axis of the rotary shaft as viewed in the axial direction of the output shaft.

6. A motor with a reduction mechanism according to any one of claims 1 to 5,

the motion conversion mechanism includes a coupling member coupled to the first shaft and the output shaft.

7. The motor with a reduction mechanism according to claim 6,

the housing includes a cover member that closes an opening portion of the housing,

the coupling member includes a coupling portion that couples the first shaft and the output shaft, and a contact portion that contacts the cover member,

the coupling portion is integrally formed with the abutting portion.

8. The motor with a reduction mechanism according to claim 7,

the abutting portion is formed of an elastic member made of rubber.

9. A motor with a reduction mechanism according to any one of claims 1 to 8,

the rod is of a curved or bent shape having a recess in the center of the rod.

10. The motor with a reduction mechanism according to any one of claims 1 to 9,

the output shaft is provided to protrude toward the opening of the housing.

11. The motor with a reduction mechanism according to any one of claims 1 to 10,

the second shaft is disposed at a position shifted from the first shaft in a longitudinal direction of the worm shaft when viewed from an axial direction of the output shaft.

12. The motor with a reduction mechanism according to any one of claims 1 to 11,

the reduction mechanism includes at least one of one or more first reduction gears that transmit rotation of the first gear to the second gear and one or more second reduction gears that transmit rotation of the worm to the first gear.

Technical Field

The present invention relates to a motor with a reduction mechanism.

Background

A motor used as a driving source of a rear wiper device or the like mounted on a vehicle includes a transmission for downsizing and increasing output.

Patent document 1 discloses a motor with a reduction mechanism to which a reduction gear including a worm, a worm wheel, and a sector gear is attached. In the above-described motor with a reduction mechanism, the rotation of the motor is converted into a reciprocating oscillating motion by a motion conversion member including a sector gear. Further, a primary speed reduction mechanism is adopted as the speed reduction mechanism, and a speed reduction gear is provided between the worm and the sector gear.

Disclosure of Invention

Technical problem to be solved by the invention

As described in patent document 1, when the one-stage speed reduction mechanism is adopted, the speed reduction ratio needs to be increased in size. Further, since the sector gear of the motion conversion member swings, a wide space for allowing the sector gear to swing is required, and there is a problem that miniaturization is difficult.

Accordingly, an object of the present invention is to provide a motor with a reduction mechanism, which can increase a reduction ratio and suppress an increase in size of the reduction mechanism.

Technical scheme for solving technical problem

The above object of the present invention can be achieved by the following configurations. That is, a motor with a reduction mechanism according to a first aspect of the present invention includes: a motor section; a speed reduction mechanism that reduces the rotation of the rotating body of the motor unit; a motion conversion mechanism that converts the rotational motion of the reduction mechanism into a reciprocating rotational motion and transmits the reciprocating rotational motion to an output shaft; and a housing that houses the speed reduction mechanism and the motion conversion mechanism. The speed reduction mechanism includes: a worm provided on a rotation shaft of the motor unit; a first gear that transmits rotation of the worm and rotates about a first shaft provided in the housing; and a second gear that transmits rotation of the first gear and rotates around a second shaft provided at a position different from the first shaft in the housing. The motion conversion mechanism includes: a rotating member having a sector gear and rotating about an axis of the first shaft; and a lever coupling the second gear and the rotating member. The output shaft has an output gear that meshes with the sector gear.

According to a second mode, the sector gear is provided at an end portion of the rotating member on the opposite side from the lever.

According to the third aspect, the rotating member is axially supported by any one member of a shaft member shared with the first gear, a concave portion or a convex portion provided on an end surface of the first gear, and a shaft member protruding from an end surface of the first gear.

According to a fourth aspect, the lever is provided so that at least a part thereof is sandwiched by the rotating member and the second gear, or the lever is provided on the same side with respect to the rotating member and the second gear in a direction along the axis of the first shaft or the second shaft.

According to a fifth aspect, the first shaft is disposed on one side with respect to the axis of the rotary shaft when viewed in the axial direction of the output shaft, and the second shaft is disposed on the other side with respect to the axis of the rotary shaft when viewed in the axial direction of the output shaft.

According to a sixth aspect, the motion conversion mechanism includes a coupling member coupled to the first shaft and the output shaft.

According to a seventh aspect, the housing includes a cover member that closes an opening of the housing, the coupling member includes a coupling portion that couples the first axis and the output shaft, and an abutting portion that abuts against the cover member, and the coupling portion and the abutting portion are integrally formed.

According to an eighth aspect, the abutting portion is formed of an elastic member made of rubber.

According to a ninth aspect, the rod is a curved or bent shape having a recess provided in the center of the rod.

According to a tenth mode, the output shaft is provided so as to protrude toward the opening of the housing.

According to the eleventh aspect, the second shaft is disposed at a position shifted from the first shaft in the longitudinal direction of the worm shaft when viewed from the axial direction of the output shaft.

According to a twelfth aspect, the reduction mechanism includes at least one of one or more first reduction gears that transmit the rotation of the first gear to the second gear and one or more second reduction gears that transmit the rotation of the worm to the first gear.

Effects of the invention

According to the first aspect, the reduction mechanism performs reduction in two or more stages by at least two gears, that is, the first gear and the second gear, and therefore, the reduction ratio can be increased. Further, since the rotary member rotates about the axis of the first shaft, which is the rotation center of the first gear, the movable region of the rotary member can be reduced. Further, since the axis of the first shaft which is the shaft of the first gear coincides with the axis of the rotating member having the sector gear, a large portion of the rotating member overlaps the first gear when viewed from the output shaft direction, and an increase in the area of the reduction mechanism when viewed from the output shaft direction can be suppressed.

According to the second aspect, the sector gear is provided at the end portion of the rotary member on the opposite side to the lever, so that the sector gear can be appropriately reciprocated and rotated by the power applied from the lever to the rotary member while the size of the rotary member can be suppressed.

According to the third aspect, since the rotary member is axially supported by any one member of the shaft member shared with the first gear, the concave portion or the convex portion provided on the end surface of the first gear, and the shaft member protruding from the end surface of the first gear, the rotary member and the first gear can share the axis of the first shaft as a shared rotation center, and the degree of freedom in design can be improved.

According to the fourth aspect, since the lever can be disposed so that at least a part thereof is sandwiched by the rotating member and the second gear, and the lever is disposed on the same side with respect to the rotating member and the second gear in the direction along the axis of the first shaft or the second shaft, the degree of freedom in design can be improved.

According to the fifth aspect, since the first shaft is disposed on one side with respect to the axis of the rotary shaft and the second shaft is disposed on the other side with respect to the axis of the rotary shaft as viewed in the axial direction of the output shaft, the reduction mechanism can be suppressed from becoming larger only on one side or the other side with respect to the axis of the rotary shaft. This can suppress an increase in the dead space existing between the speed reduction mechanism and the motor unit.

According to the sixth aspect, by providing the coupling member coupled to the first shaft and the output shaft, the play in the axial direction and the radial direction of the output shaft can be reduced. Further, since the rotating member rotates about the first shaft, the coupling member is not movable, and the structure of the coupling member is simplified and the design is easy.

According to the seventh aspect, since the connection portion and the contact portion are integrally formed, the number of components and the number of assembly steps can be reduced.

According to the eighth aspect, since the coupling member is immovable, the abutting portion can be manufactured by an elastic member made of inexpensive rubber, so that the manufacturing is easy and the material cost is also inexpensive.

According to the ninth aspect, the rod has a curved or bent shape in which a concave portion is provided at the center of the rod. The contact between the lever and the first shaft can be avoided, and the increase in the area of the motion conversion mechanism as viewed in the axial direction of the output shaft can be suppressed.

According to the tenth aspect, when used in a rear wiper device, the motor with the speed reduction mechanism can be attached to the surface of the mounting bracket on the side opposite to the inner panel mounting surface, and the output shaft can be disposed so as to project toward the inner panel.

According to the eleventh aspect, while suppressing an increase in size of the speed reduction mechanism in a direction orthogonal to the axial direction of the rotating shaft when viewed from the axial direction of the output shaft, the degree of freedom in the arrangement of the first shaft and the second shaft can be increased, and the degree of freedom in the design of each part can be increased.

According to the twelfth aspect, it is possible to use reduction gears of multiple stages, and to increase the reduction ratio while suppressing an increase in size. This also enables further downsizing of the motor unit.

Drawings

Fig. 1 is a perspective view of a motor with a reduction mechanism according to a first embodiment.

Fig. 2 is an exploded perspective view of fig. 1.

Fig. 3 is an operation explanatory diagram of fig. 1, in which fig. 3A is an automatic stop position (0 °), fig. 3B is a 90 ° rotated position, fig. 3C is a swing angle 1/2 position, fig. 3D is a position where the lever is closest to the first shaft, fig. 3E is a 180 ° rotated position, and fig. 3F is a 270 ° rotated position.

Fig. 4 shows a modification of the first shaft, fig. 4A shows an example of fig. 1 and 2, fig. 4B shows an example of the first gear having a convex portion, fig. 4C shows an example of the first gear having a concave portion, and fig. 4D shows an example of the first gear having a pin.

Fig. 5 is a modification of the lever arrangement, fig. 5A is an example of fig. 1 and 2, and fig. 5B is an example in which the lever is provided on the same side in the direction along the axis of the rotary member and the second gear.

Fig. 6 is a plan view of a motor with a reduction mechanism according to a second embodiment.

Fig. 7 is a perspective view of a motor with a reduction mechanism according to a third embodiment.

Fig. 8 is an exploded perspective view of fig. 7.

Fig. 9 is a plan view of a motor with a reduction mechanism according to a fourth embodiment.

Detailed Description

Hereinafter, the motor with a reduction mechanism according to the present invention will be described in detail with reference to the drawings. However, the embodiments described below exemplify a motor with a speed reduction mechanism for embodying the technical idea of the present invention, and the present invention is not limited to these embodiments, and may be applied to other embodiments included in the claims.

[ first embodiment ]

A motor 1 with a reduction mechanism according to a first embodiment of the present invention will be described with reference to fig. 1 to 5. Although an example in which the motor 1 with a speed reduction mechanism is used to drive the rear wiper device is described here, the use of the motor 1 with a speed reduction mechanism is not limited to driving the rear wiper device.

Fig. 1 is a perspective view of a motor 1 with a reduction mechanism according to a first embodiment, and fig. 2 is an exploded perspective view of fig. 1. The motor 1 with a speed reduction mechanism includes a motor unit 2, a housing 41, a speed reduction mechanism 3, a motion conversion mechanism 4, and a cover member (not shown) that covers at least an opening of the housing 41.

The motor unit 2 is provided with a motor housing 10, a bearing 12, and a connector 13. The motor case 10 is, for example, a bottomed cylindrical shape and is made of a magnetic body such as iron, and a permanent magnet 42 (see fig. 6) of, for example, 2 to 4 poles is provided inside. The armature 43 (see fig. 6) is provided to face the permanent magnet 42, and the rotating shaft 11 is provided at the center of the armature 43. One end of the rotary shaft 11 is rotatably supported by a bearing 12. The form of the motor is not particularly limited, but for example, a 2-pole motor with a brush may be used. In the brush-equipped dc motor, in order to supply power to the armature 43, brushes are provided on the stator, and a commutator is provided on the armature 43.

The housing 41 is a bottomed substantially rectangular shape having a housing portion 44 that houses the speed reduction mechanism 3 and the motion conversion mechanism 4, and has a short side in the axial direction of the rotary shaft 11 and a long side in the direction orthogonal to the axial direction of the rotary shaft 11. The housing 41 may be formed by molding, for example, aluminum or an aluminum alloy. The first gear 17 and the output shaft 37 are provided on one side of the worm 15, and the second gear 23 is provided on the other side, as viewed from the direction of the output shaft 37.

A worm 15 is provided on the tip end side of the rotating shaft 11, and the tip end of the worm 15 is rotatably supported by a worm bearing 16. For example, the worm 15 may be formed integrally with the rotary shaft 11, or may be connected to the tip of the rotary shaft 11.

A first shaft 21 fixed to the housing 41 and extending toward the opening side of the housing 41 is provided on one side (hereinafter, referred to as "one side") in a direction orthogonal to the axis of the worm 15 and the axis of the output shaft 37 when viewed in the axial direction of the output shaft 37. Further, a flat disk-shaped first gear 17 is rotatably provided on one side. The first gear 17 is formed of a large-diameter gear 18 and a small-diameter gear 19, the large-diameter gear 18 being provided on the back surface side of the first gear 17 (the bottom side of the housing 41 in the axial direction of the output shaft 37) and meshing with the worm 15, and the small-diameter gear 19 being provided on the same axis as the large-diameter gear 18 and on the front surface side of the first gear 17 (the opening side of the housing 41 in the axial direction of the output shaft 37). A first shaft through hole 20 is provided in the center of the first gear 17, and the first gear 17 is rotatable relative to the first shaft 21 by inserting the first shaft 21 through the first shaft through hole 20. The material of the first gear 17 may be, for example, resin, but is not limited to this, and may be, for example, metal.

A second shaft 27 fixed to the housing 41 and extending toward the opening side of the housing 41 is provided on the other side (the opposite side to the one side, hereinafter referred to as "the other side") in the direction orthogonal to the axis of the worm 15 and the axis of the output shaft 37 as viewed in the axial direction of the output shaft 37. Further, a flat disk-shaped second gear 23 is rotatably provided on the other side. An outer peripheral tooth portion 24 that meshes with the small-diameter gear 19 is provided on the outer periphery of the second gear 23. A second shaft through hole 25 is provided in the center of the second gear 23, and the second gear 23 is rotatable relative to the second shaft 27 by inserting the second shaft 27 through the second shaft through hole 25.

In the first embodiment, the first shaft 21 (the axis of the first shaft 21) is provided on one side of the worm 15 and the second shaft 27 (the axis of the second shaft 27) is provided on the other side as viewed in the axial direction of the output shaft 37. However, the arrangement of the first shaft 21 and the second shaft 27 is not limited, and for example, the first shaft and the second shaft may be provided only on one side or the other side of the worm 15 as viewed in the axial direction of the output shaft 37. Further, the second shaft 27 (the axis of the second shaft 27) is provided closer to the tip end side (the opposite side to the motor portion 2) of the worm 15 than the first shaft 21 (the axis of the first shaft 21) in the axial direction of the worm 15. However, the arrangement of the first shaft 21 and the second shaft 27 is not particularly limited, and the second shaft 27 may be provided closer to the motor unit 2 than the first shaft 21 in the axial direction of the worm 15, for example. Further, the first shaft 21 and the second shaft 27 may be arranged at the same position in the axial direction of the worm 15.

A pair of rod coupling recesses 26 are provided on the front surface side of the second gear 23 at predetermined positions between the second shaft through hole 25 and the outer peripheral tooth portion 24 in the radial direction. The pair of rod coupling recesses 26 are provided symmetrically (at an interval of 180 °) across, for example, the second shaft through hole 25. The rod coupling recess 26 may be a bottomed recess or a through hole. The second gear 23 may be made of, for example, resin, but is not limited thereto, and may be made of, for example, metal.

On the back surface side of the second gear 23, an unillustrated conductive plate is provided, and the conductive plate is brought into electrical connection by coming into contact with the contact plate 14. According to the pattern of the conductive plate, by changing the contact state and the non-contact state with the contact plate 14, the wiper arm is controlled to stop at the lower reverse position even if the wiper switch is turned off during driving of the wiper arm (in a state other than the lower reverse position).

A second gear-side projection 29 of a lever 28, which will be described later, is rotatably inserted into one of the pair of lever coupling recesses 26. By inserting the second gear-side projection 29 into any one of the pair of lever coupling concave portions 26, it is possible to select whether the stop position of the wiper arm is located at the lower reverse rotation position or the upper reverse rotation position. The number of the rod coupling recesses 26 is not limited to two, and may be a plurality of four or the like, or may be one.

A lever 28 is provided on the surface side of the second gear 23. The rod 28 is flat and bent into a substantially circular bracket-shaped elongated plate shape. In one example, the lever 28 is a long plate-like member bent in a direction orthogonal to a straight line connecting the second gear-side projection 29 and a rotating member-side projection 30, which will be described later, on the opposite side of the motor unit 2 as viewed from the output shaft 37. The rod 28 may be made of a metal such as iron or a sintered metal. The second gear-side projection 29 projects toward the back side (bottom side of the housing 41) on one end side in the longitudinal direction of the lever 28, and the rotating member-side projection 30 projects toward the front side (opening side of the housing 41) on the other end side.

Since the lever 28 is bent in a substantially circular bracket shape, a recess 31 that opens toward the motor section 2 is provided in the central portion. By providing the recess 31, the lever 28 can be prevented from contacting the first shaft 21 when the lever 28 swings with the rotation of the second gear 23. Further, although the concave portion 31 that opens toward the motor portion 2 is provided in the center portion of the lever 28 in the present embodiment, the present invention is not limited to this. For example, the rod may be a linear elongated rod without a recess. Further, the rod 28 may be bent to form a recess in the central portion of the rod 28.

A flat, substantially semicircular rotating member 32 is provided on the front surface side of the lever 28. The rotating member 32 may be made of metal such as iron or sintered metal. A rotation center hole 35 is provided at a substantially center of the substantially semicircular rotation member 32. A rod-side through hole 34 is provided at one end of the arc of the rotating member 32, and a sector gear 33 is provided from one end side to the other end side excluding the one end of the arc. The sector gear 33 is formed of a plurality of convex portions extending radially outward from the arc of the rotating member 32. The rotating member side projection 30 of the lever 28 is rotatably inserted into the lever side through hole 34. That is, the sector gear 33 is provided at an end portion of the rotating member 32 on the opposite side to the lever 28.

The first shaft 21 inserted into the first gear 17 is also rotatably inserted into the rotating member 32. In detail, the rotation center hole 35 of the rotation member 32 is inserted by the first shaft 21. That is, the first gear 17 and the rotary member 32 share the first shaft 21 as a rotation center, and the axis of the first gear 17, the rotation center of the rotary member 32, and the axis of the first shaft 21 coincide. Further, the rotating member 32 is located on the surface side of the first gear 17 (the opening side of the housing 41).

An output shaft 37 protruding to the front side (the opening side of the housing 41) is provided on one side (the opposite side to the second shaft 27) of the first gear 17. The output shaft 37 is rotatably supported by an output bearing 40 provided in a housing 41. An output gear 38 is provided on the base end side of the output shaft 37 (the bottom side of the housing 41), and a clutch 39 is provided on the surface side of the output gear 38 (the tip end side of the output shaft 37). Further, the rotation of the output gear 38 is transmitted to the output shaft 37 via the clutch 39. Here, the sector gear 33 meshes with the output gear 38, and the sector gear 33 oscillates to rotate the output gear 38 in a reciprocating manner. The protruding direction of the output shaft 37 may be toward the back surface side (the bottom side of the housing 41), in which case the output shaft 37 protrudes through the bottom of the housing 41.

The clutch 39 is provided to suppress the case where an excessive load is applied to the speed reduction mechanism 3 and/or the motion conversion mechanism 4 due to an excessive load applied to the wiper arm (output shaft 37). The clutch 39 is configured to transmit the rotation of the output gear 38 to the output shaft 37 at a normal time (when the load applied to the wiper arm and the output shaft 37 is within a predetermined value). On the other hand, when an overload of a predetermined value or more is applied to the output shaft 37, the clutch 39 is configured to release the coupling between the output shaft 37 and the output gear 38, and to cause the output shaft 37 to rotate idly.

[ Effect of the first embodiment ]

The operation of the first embodiment will be described. When electric power is supplied from the connector 13 to the armature 43 via the brushes and the commutator, the armature 43 (see fig. 6) is rotated by repulsive force and attractive force acting between a magnetic field generated by the armature 43 and excitation of the permanent magnet 42 (see fig. 6) provided on the inner circumferential side of the motor housing 10. The rotation of the armature 43 is transmitted from the rotation shaft 11 to the worm 15, and drives the first gear 17 that meshes the large-diameter gear 18 with the worm 15 to rotate. That is, the first-stage reduction mechanism is constituted by the engagement of the worm 15 and the large-diameter gear 18.

The rotation of the first gear 17 is transmitted to the second gear 23 through the outer peripheral tooth portion 24 of the second gear 23 meshing with the small-diameter gear 19. That is, the second-stage reduction mechanism is constituted by the engagement of the small-diameter gear 19 and the outer peripheral tooth portion 24. Thus, the reduction mechanism 3 is configured as a two-stage reduction mechanism, and the reduction ratio can be increased as compared with the case of one-stage reduction. Further, since the first shaft 21 inserted into the first gear 17 and the second shaft 27 inserted into the second gear 23 are provided so as to face each other across the worm 15 when viewed in the axial direction of the output shaft 37, the reduction mechanism 3 can be prevented from being enlarged toward one side of the worm 15. Further, it is possible to suppress an increase in the area between the motor portion and the reduction mechanism (the area on the side of the motor portion 2 and the area on the side of the motor portion 2 of the reduction mechanism) which occurs when the reduction mechanism is increased in size toward the one side of the worm 15.

Further, since the first shaft 21 and the second shaft 27 are arranged at positions shifted in the axial direction of the worm 15 as viewed in the axial direction of the output shaft 37, the degree of freedom in arrangement of the first shaft 21 and the second shaft 27 can be increased while suppressing an increase in size in the direction orthogonal to the axial direction of the worm 15, and the degree of freedom in design of each part can be increased.

The rotation of the second gear 23 is transmitted to the rotating member 32 via the lever 28. At this time, the lever 28 swings with the rotation of the second gear 23, thereby reciprocating the rotary member 32. The second gear 23 side protrusion of the lever 28 may be set to be rotatably inserted into one of the plurality of lever coupling recesses 26 of the second gear 23, and the wiper arm may be stopped at the lower reverse position by selecting the lever coupling recess 26. That is, the conductive plate provided on the back surface side of the second gear 23 is electrically connected to the contact plate 14, and the wiper arm is controlled to stop at the lower reversing position according to the pattern of the conductive plate.

Since the lever 28 is bent in a substantially circular bracket shape (the concave portion 31 is provided at the central portion of the lever 28) when viewed from the axial direction of the output shaft 37, the lever 28 can be prevented from contacting the first shaft 21 when the lever 28 swings in accordance with the rotation of the second gear 23. This can suppress an increase in the area (movable region) of the motion conversion mechanism 4 as viewed in the axial direction of the output shaft 37.

Here, the mode of the swing motion of the lever 28 will be described with reference to fig. 3. Fig. 3A is the automatic stop position (0 °), fig. 3B is the 90 ° rotated position, fig. 3C is the swing angle 1/2 position, fig. 3D is the position where the lever 28 is closest to the first shaft 21, fig. 3E is the 180 ° rotated position, and fig. 3F is the 270 ° rotated position.

Fig. 3A is an automatic stop position (0 °), which is a position where the wiper arm is stopped at the lower inversion position. The above-described position is a state in which the rotation angle of the sector gear 33 of the turning member 32 is rotated most clockwise in the rotation stroke, and the second gear-side projection 29 of the lever 28 is located on the opposite side of the turning member 32 with respect to the second shaft 27.

Fig. 3B is a 90 ° rotated position, which is a position when the second gear 23 is rotated 90 ° clockwise from the position (automatic stop position) of fig. 3A. The above-described position is a state in which the turning member 32 is rotated slightly counterclockwise from fig. 3A, and is a position in which the second gear side projection 29 of the lever 28 is rotated 90 ° clockwise from the position of fig. 3A, the lever 28 being slightly close to the first shaft 21.

Fig. 3C shows the swing angle 1/2 position, which is the position where the rotation angle of the sector gear 33 of the rotating member 32 is located at exactly half the rotation stroke. The above-described position is a state where the turning member 32 is further rotated counterclockwise from fig. 3B, and is a position where the second gear side projection 29 of the lever 28 is further rotated clockwise from the position of fig. 3B, the lever 28 being further close to the first shaft 21.

Fig. 3D is a position where the lever 28 is closest to the first shaft 21, showing a shape designed so that the concave portion 31 of the lever 28 does not contact the first shaft 21. The above-described position is a state where the turning member 32 is further rotated counterclockwise from fig. 3C, and is a position where the second gear side projection 29 of the lever 28 is further rotated clockwise from the position of fig. 3C, and the recess 31 of the lever 28 is closest to the first shaft 21.

Fig. 3E is a 180 ° rotated position, which is a position when the second gear 23 is rotated 180 ° clockwise from the position (automatic stop position) of fig. 3A. The above-mentioned position is a position at which the rotation angle of the sector gear 33 of the rotating member 32 is rotated most counterclockwise in the rotation stroke. At the above position, the second gear-side projection 29 of the lever 28 is located at a position close to the first shaft 21, and on the other hand, the rotating member-side projection 30 of the lever 28 is located at a position close to the output shaft 37. When the second gear 23 rotates from 180 °, the rotation direction of the rotary member 32 is reversed, and becomes clockwise.

Fig. 3F is the 270 ° rotated position, which is a position when the second gear 23 is rotated 270 ° clockwise from the position (automatic stop position) of fig. 3A. At the above position, the second gear side projection 29 of the lever 28 is away from the first shaft 21, the turning member 32 is rotated clockwise from the position of fig. 3E, and the lever 28 is away from the first shaft 21.

Since the rotary member 32 performs reciprocating rotary motion about the first shaft 21, the movable region of the rotary member 32 can be reduced. The rotating member 32 is provided closer to the opening portion side of the housing 41 than a portion where the first gear 17 and the worm 15 are engaged with each other in the axial direction of the first gear 17. Further, the rotation center of the rotary member 32 is the first shaft 21 common to the first gear 17, and therefore, most of the rotary member 32 overlaps the first gear 17 as viewed from the axial direction of the output shaft 37. Furthermore, the majority of the movable area of the oscillating movement of the lever 28 coincides with the first gear 17 and the second gear 23. Therefore, the increase in the area of the speed reduction mechanism 3 and the motion conversion mechanism 4 and the increase in the size of the housing 41 can be suppressed when viewed in the axial direction of the output shaft 37.

The sector gear 33 is provided at the end portion of the rotary member 32 opposite to the rod-side through hole 34, so that the sector gear can be appropriately reciprocated and rotated by the power applied from the rod 28 to the rotary member while suppressing the increase in size of the rotary member 32. Further, the sector gear 33 can be appropriately arranged while ensuring the interval between the rotation center hole 35 and the rod side through hole 34.

The output shaft 37 protrudes to the side (cover member side) opposite to the bottom side of the housing 41. When the motor 1 with a speed reduction mechanism according to the first embodiment is used for a rear wiper device, the motor 1 with a speed reduction mechanism can be attached to the surface of the mounting bracket on the side opposite to the inner panel attachment surface, and the output shaft can be disposed so as to protrude toward the inner panel (mounting bracket).

As described above, the lever 28 reciprocates the rotary member 32 while swinging along with the rotation of the second gear 23. The sector gear 33 provided on the rotary member 32 meshes with the output gear 38, and the output shaft 37 is connected to the output gear 38 via the clutch 39, so that the output shaft 37 is driven to rotate reciprocally.

The output shaft 37 is connected to a wiper arm, not shown, and the wiper blade is supported by the tip of the wiper arm. The wiper arm and the wiper blade are oscillated within a predetermined range in accordance with the reciprocating rotational movement of the output shaft 37, whereby the wiper blade is configured to be wiped back and forth between the upper reverse position and the lower reverse position of the windshield surface.

Since the output shaft 37 is connected to the output gear 38 via the clutch 39, it is possible to suppress the application of an excessive load to the speed reduction mechanism 3 and/or the motion conversion mechanism 4 due to an excessive load applied to the wiper arm. In this case, since the output shaft 37 is directly connected to the output gear 38, the structure of the output unit including the output shaft 37 and the output gear 38 can be simplified.

Next, a modification of the first shaft will be described with reference to fig. 4.

[ modification 1]

Fig. 4A is an example in the case of fig. 1 and 2. The first shaft 21 is provided in the housing 41. The first gear 17 is inserted through the first shaft 21 so as to be disposed on the bottom side of the housing 41, and the rotating member 32 is inserted through the first shaft 21 so as to be disposed on the front side (opening side of the housing 41) of the first gear 17. That is, in this example, the first shaft 21 is used as a rotation shaft common to the first gear 17 and the rotary member 32. The first shaft 21 is inserted through the first shaft through hole 20 of the first gear 17, thereby rotatably supporting the first gear 17. The rotating member 32 is provided on the front surface side of the first gear 17 of the first shaft 21 so as to overlap the first gear 17. The rotation member 32 is rotatably supported by inserting the rotation center hole 35 of the rotation member 32 into the first shaft 21.

When a predetermined distance is required between the housing 41 and the first gear 17, an annular projection rising from the housing 41 toward the first gear 17 and/or an annular projection rising from the first gear toward the housing 41 may be provided around the first shaft 21. Hereinafter, the same applies to fig. 4B, 4C, and 4D. In addition, not only the first shaft but also a technique of providing an annular projection around the shaft may be similarly employed when a gap is to be provided between two members stacked.

[ modification 2]

Fig. 4B is an example in which the first gear 17 has a convex portion. The housing 41 is provided with a first shaft 21A shorter than the first shaft 21 in the example of fig. 4A, and the first shaft 21A is inserted into the first shaft insertion hole 20A of the first gear 17. Therefore, the first gear 17 is rotatable with respect to the first shaft 21A. A first shaft corresponding projection 20B coaxial with the first shaft 21A is provided on the front surface side of the first gear 17. The first shaft corresponding projection 20B is inserted into the rotation center hole 35 of the rotation member 32. Therefore, the rotary member 32 can relatively rotate with respect to the first axis corresponding projection 20B.

[ third modification ]

Fig. 4C is an example in which the first gear 17 has a concave portion. The housing 41 is provided with a first shaft 21A shorter than the first shaft 21 in the example of fig. 4A, and the first shaft 21A is inserted into the first shaft insertion hole 20 of the first gear 17. Therefore, the first gear 17 is rotatable with respect to the first shaft 21A. The rotating member 32 is provided with a rotation center convex portion 35A rising toward the first gear. The rotation center convex portion 35A of the rotary member 32 is relatively rotatably inserted into the surface side of the first shaft insertion hole 20 of the first gear 17. In the first shaft insertion hole 20, a predetermined distance is desirably provided between the rotation center convex portion 35A and the first shaft 21A.

Although the example in which the first shaft through-hole 20 is a through-hole having the same diameter along the axial direction has been described here, the present invention is not limited to this, and for example, an insertion hole that does not penetrate may be provided in the center of both the front side and the back side of the first gear 17, or the first shaft through-hole 20 or the insertion hole on the front side and the back side of the first gear 17 may have different diameters. Further, the diameters of the first shaft through holes 20 or the insertion holes on the front side and the back side of the first gear 17 correspond to the diameters of the rotation center convex portion 35A and the first shaft 21A, respectively.

[ modification 4]

Fig. 4D is a case where the first gear 17 has a pin. The housing 41 is provided with a first shaft 21A shorter than the first shaft 21 in the example of fig. 4A, and the first shaft 21A is inserted into the first shaft insertion hole 20 of the first gear 17. Therefore, the first gear 17 is rotatable with respect to the first shaft 21A. A pin 20C as a shaft member is inserted into the first shaft insertion hole 20 so as to protrude to the front surface side. Since the rotating member 32 has the pin 20C inserted into the rotation center hole 35, the rotating member 32 can rotate relative to the pin 20C. In addition, in the first shaft insertion hole 20, a predetermined interval is desirably provided between the pin 20C and the first shaft 21A.

Although the example in which the first shaft through-holes 20 have the same diameter has been described here, the present invention is not limited to this, and for example, an insertion hole that does not penetrate may be provided in the center of both the front side and the back side of the first gear 17, or the first shaft through-holes 20 or the insertion holes on the front side and the back side of the first gear 17 may have different diameters. Further, the diameters of the first shaft through holes 20 or the insertion holes on the front side and the back side of the first gear 17 correspond to the diameters of the pin 20C and the first shaft 21A, respectively, and the diameter of the pin 20C corresponds to the diameter of the rotation center hole 35 of the turning member 32.

Although fig. 4A to 4D are described as an example, the present invention is not limited to this, and any form may be used as long as the axis of the first shaft 21, the axis of the first gear 17, and the rotation center of the rotary member 32 coincide with each other. Since the mode of the first shaft 21 can be various as described above, the degree of freedom of design can be improved.

Next, a modified example of the arrangement of the lever 28 will be described with reference to fig. 5.

[ modification 5]

Fig. 5A is an example of the case of fig. 1 and 2, and is an example in which a part of the lever 28 is sandwiched between the second gear 23 and the rotating member 32. A second gear-side projection 29 projecting toward the back side is provided at an end portion of the lever 28 on the second gear 23 side (right side in fig. 5A), and a rotating member-side projection 30 projecting toward the front side is provided at an end portion of the lever 28 on the rotating member 32 side (left side in fig. 5A). The second gear-side projection 29 and the rotating member-side projection 30 may be formed integrally with the lever 28, for example, or may be formed by inserting a separate pin-shaped member into a through hole provided in the lever 28, for example.

The second gear side protrusion 29 of the lever 28 is inserted into one of the plurality of lever coupling concave portions 26 of the second gear 23 from the front surface side, and the second gear side protrusion 29 is relatively rotatable with respect to the lever coupling concave portion 26. On the other hand, the rotating member-side protrusion 30 is inserted into the rod-side through hole 34 of the rotating member 32 from the back side, and the rotating member-side protrusion 30 is relatively rotatable with respect to the rod-side through hole 34 of the rotating member 32. By disposing the lever 28 so as to be sandwiched between the second gear 23 and the rotary member 32, the lever 28 can be oscillated in accordance with the rotation of the second gear 23, and the rotary member 32 can be reciprocated about the rotation center hole 35.

[ modification 6]

Fig. 5B is an example in which the lever 28A is provided on the same side (the opening side of the housing 41) in the direction along the axis thereof with respect to the rotating member 32 and the second gear 23A. A second gear-side projection 29A projecting toward the back surface side is provided at an end portion of the lever 28A on the second gear 23A side (right side in fig. 5B), and a rotating member-side projection 30A projecting toward the front surface side is provided at an end portion of the lever 28A on the rotating member 32 side (left side in fig. 5B). The second gear-side projection 29A and the rotating member-side projection 30A may be formed integrally with the lever 28A, for example, or a separate pin-shaped member may be inserted into a through hole provided in the lever 28A, for example.

The second gear side projection 29A of the lever 28A is inserted into one of the plurality of lever coupling concave portions 26A of the second gear 23A from the front surface side, and the second gear side projection 29A is relatively rotatable with respect to the lever coupling concave portion 26A. On the other hand, the rotating member side projection 30A of the lever 28A is inserted into the lever side through hole 34 of the rotating member 32 from the front surface side, and the rotating member side projection 30A is relatively rotatable with respect to the lever side through hole 34 of the rotating member 32. By disposing the lever 28A on the front side of the second gear 23A and the turning member 32 in this manner, the lever 28A can be swung in accordance with the rotation of the second gear 23A, and the turning member 32 can be reciprocated about the rotation center hole 35.

Although fig. 5A and 5B are described as an example, the present invention is not limited to this, and the lever 28 may be disposed in any other manner as long as the lever 28 can be oscillated with the rotation of the second gear 23 and the rotating member 32 can be rotated back and forth around the rotation center hole 35. Since the arrangement of the rods can be variously adopted as described above, the degree of freedom of design can be improved. Although the first embodiment describes an example in which the coupling member 50 described later is not provided, the coupling member 50 may be provided to reduce play in the axial direction and the radial direction of the output shaft. In this case, the coupling member 50 can be provided on the front side or the back side of the rotary member 32.

[ second embodiment ]

A motor 1B with a reduction mechanism according to a second embodiment of the present invention will be described with reference to fig. 6. Fig. 6 is a plan view of a motor 1B with a reduction mechanism according to a second embodiment. The same reference numerals are used for the same components as those in fig. 1 to 5, and the description thereof will be omitted. In the second embodiment, the arrangement of the lever 28B and the rotary member 32B, the protruding direction of the output shaft 37B, and the provision of the coupling member 50 are different from those of the first embodiment.

When electric power is supplied from the connector 13 to the armature 43 via the brushes and the commutator, the armature 43 is rotated by repulsive force and attractive force acting between a magnetic field generated by the armature 43 and excitation of the permanent magnets 42 provided on the inner circumferential side of the motor housing 10. Although not shown in fig. 6, the rotation of the armature 43 is transmitted from the rotation shaft 11 to the worm 15, and the first gear 17 that meshes the large-diameter gear 18 with the worm 15 is driven to rotate. The first-stage reduction mechanism is constituted by meshing the worm 15 with the large-diameter gear 18.

Although not shown in fig. 6, the rotation of the first gear 17 is transmitted to the second gear 23 through the outer peripheral tooth portion 24 of the second gear 23 meshing with the small-diameter gear 19. The second-stage reduction mechanism is constituted by meshing the small-diameter gear 19 with the outer peripheral tooth portion 24. Thus, the reduction mechanism 3 is configured as a two-stage reduction mechanism, and the reduction ratio can be increased as compared with the case of one-stage reduction. Further, since the first shaft 21 inserted into the first gear 17 and the second shaft 27 inserted into the second gear 23 are provided so as to face each other across the worm 15 when viewed in the axial direction of the output shaft 37, the reduction mechanism 3 can be prevented from being enlarged toward one side of the worm 15.

Further, since the first shaft 21 and the second shaft 27 are arranged at positions shifted in the axial direction of the worm 15 as viewed in the axial direction of the output shaft 37, the degree of freedom in arrangement of the first shaft 21 and the second shaft 27 can be increased while suppressing an increase in size in the direction orthogonal to the axial direction of the worm 15, and the degree of freedom in design of each part can be increased.

The rotation of the second gear 23 is transmitted to the rotating member 32B via the lever 28B. At this time, the lever 28B swings with the rotation of the second gear 23, thereby reciprocating the rotary member 32B in a rotary motion. The second gear side projection 29B of the lever 28B may be set to be rotatably inserted into one of the plurality of lever coupling concave portions 26 of the second gear 23, and the wiper arm may be stopped at the lower reverse rotation position by selecting the lever coupling concave portion 26. That is, the conductive plate provided on the back surface side of the second gear 23 is electrically connected to the contact plate 14, and the wiper arm is controlled to stop at the lower reversing position according to the pattern of the conductive plate.

The rod 28B is bent in a substantially circular bracket shape (a recess 31B is provided at the center of the rod 28B) as viewed from the axial direction of the output shaft 37B. Therefore, it is possible to avoid the lever 28B from contacting the first shaft when the lever 28B swings with the rotation of the second gear 23. This can suppress an increase in the area of the motion conversion mechanism 4.

In the second embodiment, the rod 28B is disposed at a position close to the motor unit 2, and therefore the bending direction of the rod 28B is opposite to that of the first embodiment. That is, a recess 31B that opens to the opposite side of the motor unit 2 is provided in the center of the lever 28B. Accordingly, the arrangement of the rod-side through hole 34B (not shown) of the rotating member 32B and the sector gear 33B is also different from the first embodiment. That is, a rod-side through hole 34B is provided at an end close to the motor unit 2, and a sector gear 33B is provided at an end opposite to the motor unit 2.

The arrangement of the lever 28B in the direction of the output shaft 37B corresponds to modification 6 (fig. 5B) of the first embodiment. That is, the lever 28B is provided on the same side (surface side) in the direction along the axis thereof with respect to the rotating member 32B and the second gear 23.

The output gear 38B meshes with a sector gear 33B provided in the rotary member 32B, and since the output gear 38B is connected to the output shaft 37B via a clutch 39B, the output shaft 37B is driven to rotate reciprocally by the reciprocal rotation of the rotary member 32B. The output shaft 37B of the second embodiment protrudes to the rear side through a through hole provided in the housing 41B.

When the output shaft 37B protrudes through the housing 41B, when the motor 1B with a speed reduction mechanism according to the second embodiment is used for the rear wiper device, the motor 1B with a speed reduction mechanism is attached to the same side of the inner panel attachment surface of the attachment bracket, and the output shaft 37B is also disposed so as to protrude in the same direction (the direction protruding from the housing 41B).

In the second embodiment, the coupling member 50 is provided to reduce the play in the axial direction and the radial direction of the output shaft 37B. The coupling member 50 is provided between the rotating member 32B and the output gear 38B and a cover member (not shown) on the front side of the rotating member 32B and the output gear 38B. The first shaft 21 is inserted into a first shaft insertion hole 51 provided at one end of the coupling member 50, and the output shaft 37B is inserted into an output shaft side insertion hole 52 provided at the other end of the coupling member 50. Although the first shaft 21 and/or the output shaft 37B are described as being inserted, this is not limited to being completely inserted through the first shaft insertion hole 51 or the output shaft side insertion hole 52, and may be the case where the shafts stay inside the holes and the end surfaces of the shafts are flush with the end surfaces of the holes.

The elastic member 53 as the contact portion is provided at the center portion of the connecting member 50. The elastic member 53 is in contact with the cover member, and can press the connecting member 50 toward the back surface side. The material of the elastic member 53 is not particularly limited, but may be made of rubber or resin. In the motor 1B with a reduction mechanism of the second embodiment, the rotating member 32B reciprocates and rotates around the first shaft 21, and the rotation center of the rotating member 32B is always fixed, so that the position of the coupling member 50 does not move.

Therefore, in order to press the coupling member 50 to the back surface side, for example, an elastic member 53 made of rubber or the like may be used. The elastic member made of rubber is easy to process, can be manufactured at low cost, has vibration damping and noise reduction effects in addition to reducing axial and radial play of the output shaft, and has excellent performance as an elastic member. Further, by integrally molding the elastic member 53 and the coupling member 50, the manufacturing can be facilitated and the number of assembling processes can be reduced.

The output shaft 37B is connected to a wiper arm, not shown, and the wiper plate is supported by the tip of the wiper arm. The wiper arm and the wiper blade are configured to oscillate within a predetermined range in accordance with the reciprocating rotational movement of the output shaft 37B, thereby wiping the wiper blade back and forth between the upper reverse position and the lower reverse position of the windshield.

Since the output shaft 37B is connected to the output gear 38B via the clutch 39B, not shown, it is possible to suppress an excessive load from being applied to the speed reduction mechanism 3 and/or the motion conversion mechanism 4 due to an excessive load applied to the wiper arm. The clutch 39B is configured to transmit the rotation of the output gear 38B to the output shaft 37B at a normal time (when the load applied to the wiper arm and the output shaft 37B is within a predetermined value). On the other hand, when an overload of a predetermined value or more is applied to the output shaft 37B, the clutch 39B is configured to release the coupling between the output shaft 37B and the output gear 38B, and to cause the output shaft to rotate idly. In this case, since the output shaft 37B is directly connected to the output gear 38, the structure of the output unit including the output shaft 37B and the output gear 38B can be simplified.

[ third embodiment ]

A motor 1C with a reduction mechanism according to a third embodiment of the present invention will be described with reference to fig. 7 and 8. Fig. 7 is a perspective view of a motor with a reduction mechanism according to a third embodiment, and fig. 8 is an exploded perspective view of fig. 7. The same reference numerals are used for the same components as those in fig. 1 to 6, and the description thereof will be omitted. In the third embodiment, the arrangement of the output shaft 37C is different from that of the second embodiment, and the arrangement of the gears is different from that of the second embodiment.

In the second embodiment, the output shaft 37B is provided with respect to the rotating member 32 so as to be aligned with the first gear (rotating member 32B) in a direction substantially orthogonal to the axis of the worm 15, as viewed from the axial direction of the output shaft 37B. In the third embodiment, the output shaft 37C is provided on the tip end side of the worm 15 in the substantially axial direction of the worm 15 with respect to the first gear 17C (the rotating member 32C). This enables the dimension in the direction orthogonal to the axial direction of the worm 15 to be reduced. The arrangement of the output shaft 37C is adjusted also in the case where the second gear 27C is increased in order to increase the reduction ratio, so that the dead zone can be effectively utilized.

The second shaft 27C is located closer to the tip end side of the worm in the axial direction of the worm 15 than the first shaft 21C is, as viewed in the axial direction of the output shaft 37C. The rod 28C is substantially rectangular in plan view, but even with such a shape, the rod 28C does not contact the first shaft 21C in view of the arrangement of the gears in the third embodiment. Further, according to the arrangement of the gears, the shape of the lever 28C can be formed into a substantially circular bracket shape as in the second embodiment, and the concave portion 31B can avoid contact with the first shaft 21C.

The shape of the rotating member 32C is as follows: a rod-side through hole 34C is provided at one end portion of the rotation center hole 35C so as to extend straight on one side, and a sector gear 33C is provided along the circumference of the rotation center hole 35C so as to form a semicircular shape on the other side. In addition, the shape of the rotating member 32C, the arrangement of the rod-side through hole 34C and the sector gear 33C may be appropriately changed according to the arrangement of the respective gears.

The output shaft 37C protrudes in a direction penetrating the housing 41C, as in the second embodiment. Although the coupling member 50C is not illustrated in fig. 7 and 8, the coupling member 50C may be provided on the surface side between the first shaft 21C and the output shaft 37C. The coupling member 50C can reduce axial and radial play of the output shaft 37C.

The side of the first shaft 21C or the second shaft 27C with respect to the axis of the worm 15C as viewed in the axial direction of the output shaft 37C can be determined as appropriate according to the specification of the motor 1C with a speed reduction mechanism. In this case, when the first shaft 21C and the second shaft 27C are provided so as to be opposed to the axis of the worm 15C, the reduction mechanism 3C can be suppressed from becoming larger only on one side or the other side of the axis of the worm 15C in the direction orthogonal to the axis of the worm 15C as viewed in the axial direction of the output shaft 37C. The arrangement and direction of the connector 13 may be appropriately arranged according to the specification of the motor 1C with a speed reduction mechanism.

[ fourth embodiment ]

A motor 1D with a reduction mechanism according to a fourth embodiment of the present invention will be described with reference to fig. 9. Fig. 9 is a plan view of a motor with a reduction mechanism according to a fourth embodiment. The same reference numerals are used for the same components as those in fig. 1 to 8, and the description thereof will be omitted. In the fourth embodiment, the reduction mechanism 3D is different from the first to third embodiments in that it is configured by a three-stage reduction mechanism.