阅读说明：本技术 接合装置和接合方法 (Joining device and joining method ) 是由 山崎刚史 田代尊久 永井浩行 横山岳史 于 2019-06-28 设计创作，主要内容包括：本发明提供一种接合装置和接合方法。接合装置(10)具有通电加压头(62),该通电加压头(62)设置有与第1金属部件(14)的受压面(46)接触的抵接面(78),通过使用了通电加压头(62)的通电和加压,将第1金属部件与第2金属部件(18)接合,得到接合界面相对于受压面倾斜的接合体。抵接面具有能够向第1金属部件通电的电极部和由绝缘材料构成的绝缘部。受压面中至少与接合界面的距离最短的最短部分成为不与电极部接触的电极非接触部,绝缘部与电极非接触部的至少一部分接触。根据本发明,能够抑制在通电和加压时第1金属部件等产生挠曲等,由此能够使第1金属部件与第2金属部件良好地接合。(The invention provides a joining device and a joining method. The joining device (10) is provided with an energizing pressure head (62), the energizing pressure head (62) is provided with a contact surface (78) which is in contact with a pressure receiving surface (46) of a 1 st metal component (14), the 1 st metal component and a 2 nd metal component (18) are joined by electrification and pressurization using the energizing pressure head (62), and a joined body with a joining interface inclined relative to the pressure receiving surface is obtained. The contact surface has an electrode portion capable of applying current to the 1 st metal member and an insulating portion made of an insulating material. At least the shortest portion of the pressure receiving surface, which is the shortest distance from the bonding interface, is an electrode non-contact portion that is not in contact with the electrode portion, and the insulating portion is in contact with at least a portion of the electrode non-contact portion. According to the present invention, it is possible to suppress the occurrence of deflection or the like of the 1 st metal member or the like at the time of energization or pressurization, and thereby to favorably join the 1 st metal member and the 2 nd metal member.)

1. A joining device (10) having an energization pressurizing head (62), the energization pressurizing head (62) being provided with an abutment surface (78) that comes into contact with a pressure receiving surface (46) of a 1 st metal member (14), the 1 st metal member and a 2 nd metal member (18) being joined by energization and pressurization using the energization pressurizing head, a joined body (20) having a joining interface (30) inclined with respect to the pressure receiving surface being obtained,

the contact surface has: an electrode section (82) capable of conducting current to the 1 st metal member; and an insulating part (80) made of an insulating material,

the pressure-receiving surface has an electrode non-contact portion (83) that is not in contact with the electrode portion, the electrode non-contact portion including a shortest portion (46a) where a distance between the pressure-receiving surface and the bonding interface is shortest,

the insulating portion is in contact with at least a part of the electrode non-contact portion.

2. The joining device of claim 1,

the insulating portion is provided such that a shortest distance (La) between an end portion of the electrode portion on the insulating portion side and an approach portion closest to the pressure receiving surface in the bonding interface is longer than a shortest distance (L) between the approach portion and the pressure receiving surface.

3. The joining device of claim 1,

the insulating portion is in contact with the entirety of the electrode non-contact portion.

4. The joining device according to any one of claims 1 to 3,

the 1 st metal member is annular with a through hole (44) provided in an axial direction and the pressure receiving surface being one end surface in the axial direction, tapered portions (40, 42) having a diameter reduced from the pressure receiving surface side to the other end surface side in the axial direction are provided on an outer peripheral surface of the 1 st metal member,

the 2 nd metal part has an insertion opening (28) into which the 1 st metal part is inserted in the axial direction,

the engagement interface is provided between an outer peripheral surface of the 1 st metal part including the tapered portion and an inner peripheral surface of the insertion port of the 2 nd metal part,

the insulating portion is annular and is disposed around an outer peripheral edge of the contact surface.

5. The joining device of claim 4,

the energizing pressure head has an electrode member (66) provided with the electrode portion and an annular insulating member (68) provided with the insulating portion on one end surface,

an annular notch (74) is provided on the outer peripheral edge of the electrode member at the end of the energizing pressure head on the side where the contact surface is provided,

the insulating member is disposed in the notch portion.

6. The joining device of claim 5,

the inner peripheral surface of the insulating member abuts against a stepped surface (74a) of the notch portion,

the electrode portion and the insulating portion are formed to be coplanar.

7. The joining device of claim 4,

the distance between the joining interface and the pressure receiving surface is shortest at an outer end (30a) of the joining interface disposed radially outward of the 1 st metal member and longest at an inner end (30b) of the joining interface disposed radially center side,

a boundary (84) between the non-contact portion of the electrode and a portion in contact with the electrode portion in the pressure receiving surface is configured such that a shortest distance (La) to the outer end is substantially equal to a shortest distance (Lb) to the inner end.

8. A joining device (10) that joins a 1 st metal member (14) provided with a pressure receiving surface (46) and a joining interface (30) inclined with respect to the pressure receiving surface to a 2 nd metal member (18) by energization and pressurization,

the joining device has an electrically-pressurizing head (62), the electrically-pressurizing head (62) being provided with an abutment surface (78) that contacts the pressure-receiving surface,

the contact surface has an electrode portion (82) capable of conducting electricity to the 1 st metal member and an insulating portion (80) made of an insulating material,

the insulating portion is provided such that a shortest distance (L) between a portion of the pressure receiving surface, against which the insulating portion abuts, and the bonding interface is shorter than a shortest distance between a portion of the pressure receiving surface, against which the electrode portion abuts, and the bonding interface.

9. A joining method for joining a 1 st metal member (14) and a 2 nd metal member (18) by energization and pressurization using an energization pressurization head (62) provided with an abutment surface (78) that comes into contact with a pressure receiving surface (46) of the 1 st metal member, to obtain a joined body (20) in which a joining interface (30) is inclined with respect to the pressure receiving surface,

the abutting surface is provided with: an electrode section (82) capable of conducting current to the 1 st metal member; and an insulating part (80) made of an insulating material,

the bonding method comprises a contact process and a bonding process, wherein,

the contacting step brings the contact surface into contact with the pressure receiving surface,

the joining step includes joining the 1 st metal member and the 2 nd metal member to form the joining interface by applying a pressure force in a pressure direction orthogonal to the pressure receiving surface and applying a current to the joining head,

in the contact step, the contact surface and the pressure receiving surface are brought into contact with each other such that a portion of the pressure receiving surface including at least a shortest portion (46a) having the shortest distance to the bonding interface becomes an electrode non-contact portion (83) that is not in contact with the electrode portion, and the insulating portion contacts at least a part of the electrode non-contact portion.

10. The joining method according to claim 9,

the 1 st metal member is annular with a through hole (44) provided in an axial direction and the pressure receiving surface being one end surface in the axial direction, tapered portions (40, 42) having a diameter reduced from the pressure receiving surface side to the other end surface side in the axial direction are provided on an outer peripheral surface of the 1 st metal member,

the 2 nd metal part has an insertion opening (28) into which the 1 st metal part is inserted in the axial direction,

in the contact step, the annular insulating portion disposed around the outer peripheral edge portion of the contact surface is brought into contact with at least a part of the electrode non-contact portion,

in the joining step, the joining interface is formed between an outer peripheral surface of the 1 st metal member including the tapered portion and an inner peripheral surface of the insertion port of the 2 nd metal member.

11. The joining method according to claim 10,

the distance between the joining interface and the pressure receiving surface is shortest at an outer end (30a) of the joining interface disposed radially outward of the 1 st metal member and longest at an inner end (30b) of the joining interface disposed radially center side,

in the contacting step, the contact surface is brought into contact with the pressure-receiving surface so that a shortest distance (La) from a boundary (84) between the electrode non-contact portion and a portion in contact with the electrode portion in the pressure-receiving surface to the outer end is substantially equal to a shortest distance (Lb) from the boundary (84) to the inner end.

Technical Field

The present invention relates to a joining device and a joining method for joining a 1 st metal member and a 2 nd metal member by energization and pressurization.

Background

For example, japanese patent laid-open publication No. h 11-090621 discloses a bonding apparatus in which when a 1 st metal member and a 2 nd metal member are bonded by applying current and pressure between two electrodes, a contact surface of one electrode is brought into contact with a pressure receiving surface of the 1 st metal member. In the joined body finally obtained by this joining apparatus, the plane direction of the joining interface between the 1 st metal member and the 2 nd metal member is inclined with respect to the plane direction of the pressure receiving surface of the 1 st metal member.

Disclosure of Invention

As described above, when the joining interface is inclined with respect to the pressure receiving surface, the distance between the joining interface and the pressure receiving surface becomes different in length at each portion of the joining interface. In the portion of the joint interface, which is shorter in distance from the pressure receiving surface than the other portions, the electrical resistance is reduced, and therefore, a large current is likely to flow, and the amount of heat generation is increased. Accordingly, when the amount of heat generation at the joining interface varies, it may be difficult to satisfactorily join the 1 st metal member and the 2 nd metal member.

The invention mainly aims to provide a jointing device capable of jointing a 1 st metal component and a 2 nd metal component well.

Another object of the present invention is to provide a joining method capable of joining a 1 st metal member and a 2 nd metal member well.

A first aspect of the present invention provides a joining apparatus including an energization pressurizing head provided with a contact surface that contacts a pressure receiving surface of a 1 st metal member, wherein the 1 st metal member and a 2 nd metal member are joined by energization and pressurization using the energization pressurizing head, and a joined body having a joining interface inclined with respect to the pressure receiving surface is obtained, the contact surface including: an electrode portion capable of supplying current to the 1 st metal member; and an insulating portion made of an insulating material, wherein the pressure receiving surface has an electrode non-contact portion that does not contact the electrode portion, the electrode non-contact portion includes a shortest portion where a distance between the pressure receiving surface and the bonding interface is shortest, and the insulating portion contacts at least a part of the electrode non-contact portion.

A second aspect of the present invention provides a joining apparatus for joining a 1 st metal member, which is provided with a pressure receiving surface and a joining interface inclined with respect to the pressure receiving surface, to a 2 nd metal member by energization and pressurization, the joining apparatus including an energization head provided with an abutment surface that is in contact with the pressure receiving surface, the abutment surface including an electrode portion that is capable of energizing the 1 st metal member and an insulating portion made of an insulating material, the insulating portion being provided such that a shortest distance between a portion of the pressure receiving surface that the insulating portion abuts and the joining interface is shorter than a shortest distance between a portion of the pressure receiving surface that the electrode portion abuts and the joining interface.

A 3 rd aspect of the present invention provides a joining method for joining a 1 st metal member and a 2 nd metal member by energization and pressurization using an energization and pressurization head provided with an abutment surface that comes into contact with a pressure receiving surface of the 1 st metal member, to obtain a joined body in which a joining interface is inclined with respect to the pressure receiving surface, the abutment surface being provided with: an electrode portion capable of supplying current to the 1 st metal member; and an insulating section made of an insulating material, wherein the contact step brings the contact surface into contact with the pressure receiving surface, the bonding step applies a pressing force in a pressing direction orthogonal to the pressure receiving surface and causes the energizing and pressing head to energize to bond the 1 st metal member and the 2 nd metal member to form the bonding interface, and the contact step brings the contact surface into contact with the pressure receiving surface such that a portion of the pressure receiving surface including at least a shortest portion having a shortest distance from the bonding interface becomes an electrode non-contact section that is not in contact with the electrode section, and the insulating section contacts at least a portion of the electrode non-contact section.

According to the joining apparatus and the joining method of the present invention, since the insulating portion is provided at the predetermined position of the contact surface of the energization and pressurization head, the portion closest to the pressure receiving surface, that is, the close portion in the joining interface can be separated from the electrode portion. Therefore, the distance of current flow from the electrode portion to the proximity portion can be increased. This can suppress the amount of heat generated in the proximity portion from being larger than that in the other portion of the joining interface. As a result, the occurrence of variation in the amount of heat generation at the joining interface can be suppressed, and therefore the 1 st metal member and the 2 nd metal member can be joined favorably.

Further, since the pressing force can be applied by bringing the electrode portion into contact with not only the pressure-receiving surface of the 1 st metal member but also the insulating portion into contact with the pressure-receiving surface of the 1 st metal member, the 1 st metal member and the 2 nd metal member can be favorably joined while suppressing occurrence of flexure or the like of the 1 st metal member or the like at the time of energization and pressing.

The above objects, features and advantages can be easily understood by the following description of the embodiments with reference to the accompanying drawings.

Drawings

Fig. 1 is a schematic configuration diagram of a main part of a bonding apparatus according to an embodiment of the present invention.

Fig. 2 is a sectional view of a valve seat (1 st metal member) and a cylinder head (cylinder head) main body (2 nd metal member) which can be joined by applying the joining apparatus of fig. 1.

Fig. 3 is an enlarged cross-sectional view of a main portion of a cylinder head obtained by processing a joined body obtained by joining the valve seat material and the cylinder head body shown in fig. 2.

Fig. 4 is a schematic sectional view of a main portion of an energization pressurizing head of the joining apparatus of fig. 1.

Fig. 5 is a bottom view of the energization pressurizing head of fig. 4.

Fig. 6 is a flowchart showing an example of the joining method according to the embodiment of the present invention.

Fig. 7 is an explanatory diagram for explaining a state in which the abutment surface of the energization pressurizing head is brought into contact with the pressure receiving surface of the valve seat material, and the 1 st joint surface of the valve seat material is brought into abutment with the convex portion provided on the 2 nd joint surface of the cylinder head body.

Fig. 8 is an explanatory diagram for explaining a state in which the convex portion of fig. 7 is melted to bring the valve seat material and the cylinder head body close to each other.

Fig. 9 is an explanatory diagram for explaining a state in which the valve seat material and the cylinder head body of fig. 8 are brought closer to each other to form a joint interface between the 1 st joint surface and the 2 nd joint surface.

Detailed Description

Hereinafter, a joining apparatus and a joining method according to the present invention will be described in detail with reference to the drawings, taking preferred embodiments as examples. In the following drawings, the same reference numerals are given to the same components or components that achieve the same functions and effects, and redundant description may be omitted.

Next, an example will be described in which a 1 st metal member 14, which is a workpiece (hereinafter also referred to as a "valve seat material 12") finally machined into a valve seat 12a (see fig. 3), is joined to a 2 nd metal member 18, which is a cylinder head body 16, to obtain a joined body 20 (see fig. 9) by applying the joining apparatus 10 according to the present embodiment shown in fig. 1. The joined body 20 obtained by using the joining apparatus 10 is subjected to machining or the like using, for example, a cutting apparatus not shown, and a valve contact surface 22 is formed on the valve seat member 12 as shown in fig. 3, thereby obtaining a cylinder head 24 having a valve seat 12 a.

However, the 1 st metal member 14 and the 2 nd metal member 18 that can be joined by applying the joining apparatus 10 are not limited to the valve seat material 12 and the cylinder head body 16.

First, the cylinder head 24 will be briefly described with reference to fig. 3. The cylinder head body 16 is formed with ports (ports) 26 whose one end side (arrow X1 side) is opened toward the combustion chamber (not shown). An annular valve seat 12a is inserted into an insertion port 28 at an opening peripheral edge portion on one end side (arrow X1 side) of the port 26, and an outer peripheral surface of the valve seat 12a is joined to an inner peripheral surface of the insertion port 28 via a joining interface 30. Specifically, the 1 st joint surface 32 provided on the outer peripheral surface of the valve seat 12a and the 2 nd joint surface 34 provided on the inner peripheral surface of the insertion port 28 are joined by the joint interface 30.

In the cylinder head 24, a valve contact surface 22 inclined in a direction expanding in diameter toward the combustion chamber side is provided on the valve seat 12a, and the port 26 can be opened and closed by the contact or separation of a valve, not shown, with respect to the valve contact surface 22. That is, in the cylinder head 24, the valve seat 12a is joined to a position of the cylinder head body 16 against which the valve abuts.

Next, the valve seat material 12 and the cylinder head body 16 before joining, in other words, before the joined body 20 (see fig. 9) is formed, will be described with reference to fig. 2, 7 to 9. As shown in fig. 2, the valve seat material 12 before joining is not formed with the valve abutment surface 22 (see fig. 3). In addition, in the cylinder head body 16 before joining, a convex portion 36 is provided on the 2 nd joining surface 34.

As shown in fig. 2, the valve seat member 12 is inserted into the insertion port 28 from one end side (arrow X1 side) toward the other end side (arrow X2 side) in the axial direction of the insertion port 28 in a state where the axial directions (arrow X1 and X2 directions) of the valve seat member are aligned with each other and the radial directions (arrow Y direction) of the valve seat member are parallel to each other with respect to the insertion port 28.

Hereinafter, the distal end side (arrow X2 side) of the valve seat member 12 in the insertion direction when the valve seat member 12 is inserted into the insertion port 28 is also simply referred to as the "distal end side", and the proximal end side (arrow X1 side) opposite to the insertion direction is also simply referred to as the "proximal end side". The outer side of the valve seat member 12 and the insertion port 28 in the radial direction (the direction of arrow Y) is simply referred to as "outer side", and the center side is simply referred to as "center side".

The valve seat member 12 is, for example, an annular ring-shaped member formed of a sintered body of an iron-based material such as a steel material. Further, the valve seat material 12 may include a high-conductivity material such as a copper-based material. As shown in fig. 2, the face direction of the tip end face 38 of the valve seat material 12 is arranged along the radial direction of the valve seat material 12.

The 1 st tapered portion 40 and the 2 nd tapered portion 42 having different surface directions from each other are provided on the outer peripheral surface of the valve seat material 12. The 1 st tapered portion 40 and the 2 nd tapered portion 42 are tapered portions each having a diameter decreasing from the base end side toward the tip end side. The 1 st tapered portion 40 is disposed on the tip side of the 2 nd tapered portion 42, and the base end portion of the 1 st tapered portion 40 coincides with the tip end portion of the 2 nd tapered portion 42. The tip of the 1 st tapered portion 40 coincides with the outer end of the tip end surface 38.

As shown in fig. 9, in the valve seat material 12, the base end side portion of the 1 st tapered portion 40 and the tip end side portion of the 2 nd tapered portion 42 serve as the 1 st bonding surface 32. As shown in fig. 2, a through hole 44 is provided in the axial direction on the center side of the valve seat material 12. The surface direction of the pressure receiving surface 46, which is the end surface on the base end side of the valve seat material 12, is orthogonal to the axial direction (the direction of arrows X1, X2).

The cylinder head body 16 is made of an aluminum material such as pure aluminum or aluminum alloy. As shown in fig. 2, a projection 36 projecting in an annular shape and a tapered surface 50 are provided on the inner peripheral surface of the insertion port 28 of the cylinder head body 16. When the valve seat material 12 and the cylinder head body 16 are joined, the convex portion 36 is not formed, and the 2 nd joining surface 34 is formed instead. The 2 nd bonding surface 34 is shaped to follow the 1 st bonding surface 32 of the seat material 12 when the bonding interface 30 (see fig. 9) is formed.

The tapered surface 50 is tapered so as to extend from the end of the 2 nd bonding surface 34 on the base end side (the arrow X1 direction side) further toward the base end side in the direction of expanding the diameter of the insertion port 28. The tapered surface 50 and the 2 nd tapered portion 42 of the valve seat material 12 are shaped such that the valve seat material 12 and the cylinder head body 16 are brought into a desired joined positional relationship when the center-side end 50a (see fig. 7 and 8) of the tapered surface 50 abuts against the 2 nd tapered portion 42, for example, by making the taper angles of the tapered surface 50 substantially equal to each other, or by making the inclination angle of the tapered surface 50 slightly larger with respect to the axial direction.

As shown in fig. 9, in the joined body 20, the valve seat material 12 and the cylinder head main body 16 are joined by the joining interface 30, and the valve abutment surface 22 is not provided on the valve seat material 12 (see fig. 3). That is, in the valve seat material 12 of the joined body 20, the central side portion thereof is not cut and removed. In this joined body 20, the surface direction of the joining interface 30 is inclined with respect to the surface direction of the pressure receiving surface 46 of the valve seat material 12.

Specifically, the joining interface 30 is inclined with respect to the pressure receiving surface 46 such that the outer end 30a, which is the outer end of the joining interface 30, is closest to the pressure receiving surface 46, and the inner end 30b, which is the central end of the joining interface 30, is farthest from the pressure receiving surface 46. Therefore, the distance between the joining interface 30 and the pressure receiving surface 46 in the axial direction (the direction of arrows X1, X2, the pressing direction described later) is shortest at the outer end 30a and longest at the inner end 30 b. In other words, in the joining interface 30, the outboard end 30a is closest to the pressure receiving surface 46, and the inboard end 30b is farthest from the pressure receiving surface 46.

Next, the joining apparatus 10 will be described with reference to fig. 1, 4, and 5. The joining apparatus 10 shown in fig. 1 is capable of applying pressure in the axial direction (the direction of arrows X1, X2) to the valve seat member 12 and the cylinder head body 16 and performing resistance welding by applying current, and the joining apparatus 10 mainly includes an electrode structure 60, a current-applying pressure head 62, a pressure mechanism 64, a power supply (not shown), and the like.

The cylinder head body 16 is provided on the electrode structure 60. At this time, the electrode structure 60 is in contact with the cylinder head body 16 and is electrically connected. In the cylinder head body 16 provided on the electrode structure 60, the insertion opening 28 faces the energization pressurizing head 62 side.

As shown in fig. 1, the energization pressurizing head 62 is formed by integrating an electrode member 66 and an insulating member 68. The electrode member 66 is substantially cylindrical, and one end side (arrow X1 side) in the axial direction thereof is fixed to a piston rod (piston rod)72 of the pressurizing mechanism 64 via a holder (holder) 70.

As shown in fig. 4, an annular notch 74 is provided around the outer peripheral edge on the end surface of the other end side (arrow X2 side) in the axial direction of the electrode member 66, and a projection 76 is provided to project on the radial center side. The electrode member 66 and the insulating member 68 are integrated by inserting the annular insulating member 68 made of an insulating material into the notch 74. The electrode member 66 and the insulating member 68 may be integrated by fitting or may be integrated by adhesion using an adhesive or the like.

The size of the projection 76 is set to the size of the through hole 44 (see fig. 7 and the like) into which the valve seat material 12 can be inserted. As will be described later, when the joining apparatus 10 is used for energization and pressurization, the protrusion 76 is inserted into the through hole 44 of the valve seat material 12, thereby positioning the energization and pressurization head 62 and the valve seat material 12.

In the energization and pressurization head 62, a portion other than the projection 76 of the end surface on the other end side in the axial direction is an abutment surface 78 which abuts against the pressure receiving surface 46 of the valve seat member 12 at the time of energization and pressurization. The abutment surface 78 is a plane orthogonal to the axial direction of the energization pressurizing head 62. In the contact surface 78, an end surface of the other end side (arrow X2 side) in the axial direction of the insulating member 68 serves as an insulating portion 80, and a portion of the end surface of the other end side in the axial direction of the electrode member 66 other than the protruding portion 76 serves as an electrode portion 82. As shown in fig. 9, the notch portion 74 faces a portion of the pressure receiving surface 46 including at least the shortest portion 46a, and the shortest portion 46a is a portion where the distance between the pressure receiving surface 46 and the joining interface 30 is shortest. That is, the portion of the pressure receiving surface 46 facing the cutout portion 74 serves as an electrode non-contact portion 83 which is not in contact with the electrode portion 82.

As shown in fig. 4, the inner peripheral surface 68a of the insulating member 68 abuts against the step surface 74a of the cutout portion 74, and the electrode portion 82 and the insulating portion 80 are formed to be coplanar. As shown in fig. 5, the insulating portion 80 is annular and disposed around the outer periphery of the contact surface 78, and the electrode portion 82 is annular and disposed between the insulating portion 80 and the protruding portion 76. Therefore, the contact surface 78 formed by the insulating portion 80 and the electrode portion 82 has an annular shape.

As shown in fig. 9, the insulating portion 80 provided inside the cutout portion 74 is disposed on the contact surface 78 so as to contact the electrode non-contact portion 83 of the pressure receiving surface 46. Therefore, the insulating portion 80 is disposed so that the shortest distance between the portion of the pressure receiving surface 46 with which the insulating portion 80 abuts and the bonding interface 30 is shorter than the shortest distance between the portion of the pressure receiving surface 46 with which the electrode portion 82 abuts and the bonding interface 30. That is, the insulating portion 80 is disposed such that the shortest distance La between the end of the electrode portion 82 on the insulating portion 80 side and the portion of the bonding interface 30 closest to the pressure receiving surface 46, that is, the outer end 30a of the bonding interface 30 is longer than the shortest distance L between the outer end 30a and the pressure receiving surface 46. The boundary 84 between the electrode non-contact portion 83 of the pressure receiving surface 46 and the portion in contact with the electrode portion 82 (the end portion of the electrode portion 82 on the side of the insulating portion 80) is disposed on the contact surface 78 such that the shortest distance La from the outer end 30a of the bonding interface 30 and the shortest distance Lb from the inner end 30b are substantially equal to each other.

As shown in fig. 1, the pressurizing mechanism 64 includes a pressurizing cylinder 86 formed of, for example, a hydraulic cylinder, an air cylinder, or the like. One end side (arrow X1 side) of the pressurizing cylinder 86 is fixed to the support portion 88, and the piston rod 72 that can move back and forth in the pressurizing direction is provided on the other end side (arrow X2 side) of the pressurizing cylinder 86. An energization head 62 is fixed to the other end side of the piston rod 72 via a bracket 70.

Therefore, in the pressurizing mechanism 64, the piston rod 72 is advanced, whereby the energization pressurizing head 62 and the electrode assembly 60 can be relatively brought close to each other in the pressurizing direction. Accordingly, the pressing force is applied to the valve seat material 12 and the cylinder head body 16 provided between the abutment surface 78 of the energization pressurizing head 62 and the electrode structure 60.

The power supply is electrically connected to the electrode member 66 of the energization pressurizing head 62 and the electrode structure 60. When the power is turned on, electricity can be conducted between the electrode portion 82 and the electrode structure 60. Accordingly, the current flows from the valve seat member 12 to the cylinder head body 16 through the pressure receiving surface 46 in contact with the electrode portion 82.

Next, a method of joining the valve seat material 12 and the cylinder head body 16 using the joining device 10 will be described with reference mainly to fig. 1, 6 to 9.

As shown in fig. 6, this bonding method includes a contact step and a bonding step. As shown in fig. 7, in the contact step, the protruding portion 76 of the energization pressurizing head 62 is inserted into the through hole 44 of the valve seat material 12, and the abutment surface 78 is brought into contact with the pressure receiving surface 46. As described above, the insulating portion 80 and the electrode portion 82 are disposed on the contact surface 78. Therefore, the insulating portion 80 is in contact with the electrode non-contact portion 83 in the pressure receiving surface 46. In addition, as shown in fig. 1, the cylinder head main bodies 16 are disposed on the electrode structure body 60 and are brought into contact with each other.

As shown in fig. 7, between the electrode structure 60 and the abutment surface 78 of the energization pressurizing head 62, the tapered surface 50 of the cylinder head body 16 and the 2 nd tapered portion 42 of the valve seat material 12 face each other with a space therebetween, and the apex of the convex portion 36 abuts against the 1 st tapered portion 40 (the 1 st joint surface 32). The contact step may be performed before the 1 st tapered portion 40 is brought into contact with the convex portion 36, or may be performed in a state where the 1 st tapered portion 40 is brought into contact with the convex portion 36.

Next, in the bonding step, the pressing mechanism 64 shown in fig. 1 is operated to bring the abutment surface 78 and the electrode structure 60 into relative proximity with each other, and apply a pressing force in a pressing direction perpendicular to the pressure receiving surface 46 shown in fig. 7 and the like. In the bonding step, the electrode portion 82 (see fig. 7) and the electrode assembly 60 (see fig. 1) are energized by turning on the power supply.

Accordingly, as shown in fig. 8, when the resistance welding is started, the contact portion between the valve seat material 12 and the cylinder head body 16 generates heat due to the contact resistance, and the convex portion 36 starts to melt. As shown in fig. 8, when the valve seat material 12 and the cylinder head body 16 are brought close to each other while the molten convex portion 36 is discharged from between the 1 st joint surface 32 and the 2 nd joint surface 34, the contact area between the molten convex portion 36 and the 1 st joint surface 32 increases.

As shown in fig. 9, when substantially the entire projection 36 is melted, the joint interface 30 is formed between the 1 st joint surface 32 and the 2 nd joint surface 34, and one end side of the 2 nd tapered portion 42 closer to one end than the 1 st joint surface 32 abuts against the center side end portion 50a (see fig. 8) of the tapered surface 50. In this way, the energization is stopped immediately before or at the same time as the contact of the one end side of the 2 nd tapered portion 42 closer to the one end than the 1 st joint surface 32 with the center side end portion 50a, and the resistance welding is ended. As a result, the valve seat material 12 and the cylinder head body 16 can be joined in a desired positional relationship, and the joined body 20 can be obtained.

Next, the operational effects of the joining apparatus 10 and the joining method according to the present embodiment will be described. In the bonding apparatus 10 and the bonding method, the portion of the pressure receiving surface 46 including at least the shortest portion 46a is set as the electrode non-contact portion 83 not in contact with the electrode portion 82, so that the outer end portion 30a, which is the portion of the bonding interface 30 closest to the pressure receiving surface 46, can be separated from the electrode portion 82. Accordingly, the electrical conduction distance from the electrode portion 82 to the outer end 30a can be made longer, and therefore the amount of heat generated at the outer end 30a can be suppressed from increasing compared to other portions of the joining interface 30. As a result, the occurrence of variation in the amount of heat generation at the joining interface 30 can be suppressed, and therefore the valve seat material 12 and the cylinder head body 16 can be joined favorably.

Even if the electrode non-contact portion 83 is provided on the pressure receiving surface 46 in order to suppress variation in the amount of heat generation of the bonding interface 30 as described above, the insulating portion 80 can be brought into contact with the electrode non-contact portion 83 to apply a pressure to the electrode non-contact portion 83. This can suppress the occurrence of variations in the pressing force applied from the abutment surface 78 to the pressure receiving surface 46. Further, the pressure receiving surface 46 is orthogonal to the pressing direction, and thus the pressing force can be applied efficiently and stably. This can suppress the occurrence of deflection or the like of the valve seat material 12 or the like even at the time of energization or pressurization, and can favorably join the valve seat material 12 to the cylinder head body 16.

In the joining device 10 according to the above embodiment, the 1 st metal member 14 (valve seat material 12) is provided with the through hole 44 in the axial direction, and is annular with the pressure receiving surface 46 as one end surface in the axial direction. The outer peripheral surface of the valve seat member 12 is provided with tapered portions (the 1 st tapered portion 40 and the 2 nd tapered portion 42) that are reduced in diameter from the pressure receiving surface 46 side in the axial direction toward the other end surface (the distal end surface 38) side. The 2 nd metal member 18 (cylinder head body 16) has an insertion opening 28 into which the valve seat material 12 is inserted in the axial direction. The engagement interface 30 is provided between the outer peripheral surface of the valve seat material 12 including the 1 st tapered portion 40 and the 2 nd tapered portion 42 and the inner peripheral surface of the insertion port 28 of the cylinder head body 16. The insulating portion 80 is annular and is disposed around the outer periphery of the contact surface 78.

In the joining method according to the above embodiment, the 1 st metal member 14 (valve seat material 12) is provided with the through hole 44 in the axial direction and is annular with the pressure receiving surface 46 as one end surface in the axial direction. The outer peripheral surface of the valve seat member 12 is provided with tapered portions (the 1 st tapered portion 40 and the 2 nd tapered portion 42) that are reduced in diameter from the pressure receiving surface 46 side in the axial direction toward the other end surface (the distal end surface 38) side. The 2 nd metal member 18 (cylinder head body 16) has an insertion opening 28 into which the valve seat material 12 is inserted in the axial direction. In the contact step, the annular insulating portion 80 disposed around the outer peripheral edge of the contact surface 78 is brought into contact with the electrode non-contact portion 83. In the joining process, a joining interface 30 is formed between the outer peripheral surface of the valve seat material 12 including the 1 st tapered portion 40 and the 2 nd tapered portion 42 and the inner peripheral surface of the insertion port 28 of the cylinder head body 16.

As described above, the joining apparatus 10 and the joining method using the joining apparatus 10 can be particularly preferably applied to the case where the joined body 20 is obtained by forming the joining interface 30 between the outer peripheral surface of the valve seat material 12 including the 1 st tapered portion 40 and the 2 nd tapered portion 42 and the inner peripheral surface of the insertion port 28 of the cylinder head body 16.

That is, as shown in fig. 5, by providing the annular insulating portion 80 surrounding the outer peripheral edge of the contact surface 78 on the contact surface 78, the insulating portion 80 can be easily brought into contact with the portion of the pressure receiving surface 46 including at least the shortest portion 46a, as shown in fig. 9. Accordingly, during energization and pressurization, it is possible to suppress variation in the amount of heat generation at the joining interface 30, suppress deflection of the valve seat material 12 and the like, and the valve seat material 12 and the cylinder head body 16 can be joined well.

The energization pressurizing head 62 includes an electrode member 66 provided with an electrode portion 82 and an annular insulating member 68 provided with an insulating portion 80 at one end surface. An annular notch 74 is provided on the outer peripheral edge of the electrode member 66 at the end on the side where the contact surface 78 of the energization pressurizing head 62 is provided, and the insulating member 68 is disposed in the notch 74. With this configuration, the insulating portion 80 can be accurately and easily arranged at a desired position when the energization pressurizing head 62 is assembled.

The inner peripheral surface 68a of the insulating member 68 abuts the step surface 74a of the cutout portion 74, and the electrode portion 82 and the insulating portion 80 are formed to be coplanar. That is, the insulating portion 80 is in contact with the entire electrode non-contact portion 83. With this configuration, the contact area of the contact surface 78 with respect to the pressure receiving surface 46 can be further increased, and therefore the pressurizing force can be applied more effectively.

In the joining device 10 according to the above embodiment, the distance between the joining interface 30 and the pressure receiving surface 46 is shortest at the outer end 30a of the joining interface 30 disposed radially outward of the 1 st metal member 14 (valve seat material 12), and longest at the inner end 30b of the joining interface 30 disposed radially central. The boundary between the electrode non-contact portion 83 and the portion in contact with the electrode portion 82, in other words, the boundary 84 of the contact surface 78, of the pressure receiving surface 46 is arranged such that the shortest distance La to the outer end 30a is substantially equal to the shortest distance Lb to the inner end 30 b.

In the joining method according to the above embodiment, the distance in the pressing direction between the joining interface 30 and the pressure receiving surface 46 is shortest at the outer end 30a of the joining interface 30 disposed radially outward of the 1 st metal member 14 (valve seat material 12), and longest at the inner end 30b of the joining interface 30 disposed radially central side. In the contact step, the abutment surface 78 is brought into contact with the pressure receiving surface 46 such that the shortest distance La from the boundary 84 to the outer end 30a is substantially equal to the shortest distance Lb from the boundary 84 to the inner end 30 b.

By arranging the boundary 84 as described above, the electrical conduction distance can be equalized over the entire joining interface 30, and therefore, the occurrence of variation in the amount of heat generation of the joining interface 30 can be more effectively suppressed. As a result, the valve seat material 12 and the cylinder head body 16 can be joined more favorably.

The present invention is not particularly limited to the above-described embodiments, and various modifications can be made without departing from the scope of the invention.

For example, the insulating portion 80 is not limited to an annular shape, and may have a shape that can contact at least a part of the electrode non-contact portion 83 of the pressure receiving surface 46. The shape of the outer peripheral surface of the valve seat material 12 is not limited to the above embodiment. Instead of the two 1 st and 2 nd taper portions 40 and 42 having different plane directions, one taper portion may be provided, or three or more taper portions may be provided. In addition, an arc portion may be provided instead of the 1 st tapered portion 40 and the 2 nd tapered portion 42.

In the above embodiment, the distance between the joining interface 30 and the pressure receiving surface 46 is shortest at the outer end 30a and longest at the inner end 30b, but is not particularly limited thereto. For example, the distance between the joining interface 30 and the pressure receiving surface 46 may be longest at the outer end 30a and shortest at the inner end 30 b. In this case, the electrode portion 82 is disposed so as to surround the outer peripheral edge of the contact surface 78, and the insulating portion 80 is disposed on the center side of the electrode portion 82, whereby the same operational effects as those of the above-described embodiment can be obtained.

The engagement interface 30 is provided between the outer peripheral surface of the valve seat material 12 including the 1 st tapered portion 40 and the 2 nd tapered portion 42 and the inner peripheral surface of the insertion port 28 of the cylinder head body 16. That is, the joining interface 30 has a shape corresponding to the outer peripheral surface of the truncated cone. However, the shape of the joining interface 30 is not particularly limited thereto. When the 1 st metal member 14 and the 2 nd metal member 18 are joined by the joining interface 30 having a portion inclined with respect to the surface direction of the pressure receiving surface 46, the same operational effects as those of the above-described embodiment can be obtained by applying the joining apparatus and the joining method according to the present invention.