JP6748742B2 - Electrode tip - Google Patents

Description

The present invention relates to an electrode tip for resistance welding.

Japanese Unexamined Patent Publication No. 9-155563 discloses a spot welding electrode in which a tip of a shank is fitted in a recess formed in a base end surface of an electrode tip. In this spot welding electrode, a protector having a passage hole through which a coolant introduced from the refrigerant pipe flows is connected to the tip of the refrigerant pipe disposed in the shank, and the protector and the recess of the electrode tip are By reducing the gap with the bottom surface, the flow velocity of the cooling liquid flowing through the bottom surface of the recess of the electrode tip is increased.

Generally, an electrode tip for resistance welding needs to have a thick tip portion to receive a pressure force during welding. Therefore, even if the flow rate of the cooling liquid flowing through the inner surface of the tip portion of the electrode tip (bottom surface of the recess) is increased as in the above-mentioned Japanese Patent Laid-Open No. 9-155563, the outer surface of the tip portion of the electrode tip is effectively Cooling is not easy. On the other hand, if the tip portion of the electrode tip is thinned, the electrode tip may be deformed during welding.

The present invention has been made in consideration of such problems, and an object thereof is to provide an electrode tip capable of effectively cooling the outer surface while suppressing deformation of the electrode tip during welding.

In order to achieve the above-mentioned object, the electrode tip according to the present invention is an electrode tip for resistance welding, in which an inner cylinder part in which a first flow path through which a refrigerant flows is formed, and an inner cylinder part An outer cylinder part arranged on the outer peripheral side of the inner cylinder part so as to form a second flow path through which the coolant flows, and a welding part which is provided so as to close an opening on the tip side of the outer cylinder part, A tip plate portion that abuts the work at times, and a support portion that connects the outer peripheral surface of the inner cylindrical portion and the inner peripheral surface of the outer cylindrical portion to each other are provided, and the inner cylindrical portion is the above-mentioned when welding the work. A communication hole that supports the inner surface of the tip plate portion and that communicates the first flow path and the second flow path with each other is formed at the front end portion of the inner cylindrical portion.

According to this structure, the load (pressure) applied to the tip plate portion during welding can be received by the inner tube portion supported by the outer tube portion through the support portion, so that the tip plate portion is deformed. It is possible to reduce the thickness of the tip plate portion while suppressing the above. In addition, since the communication hole that communicates the first flow path and the second flow path is formed at the tip portion of the inner tubular portion, it is guided from the first flow path to the inner surface of the tip plate portion through the communication hole. The refrigerant can be released to the second flow path (or the refrigerant introduced from the second flow path to the inner surface of the tip plate portion via the communication hole can be released to the first flow path). Accordingly, the inner surface of the tip plate portion is cooled by the refrigerant, so that the outer surface of the tip plate portion can be effectively cooled.

In the above electrode chip, a plurality of the support portions are provided in the circumferential direction of the inner tubular portion so as to be spaced from each other, and the communication holes are provided between the support portions of the inner tubular portion that are adjacent to each other in the circumferential direction. It may be formed at a position.

With such a configuration, the inner tubular portion can be firmly supported by the outer tubular portion by the plurality of support portions. Further, since it is possible to suppress the support portion from becoming a resistance when the refrigerant flows through the communication hole, it is possible to smoothly flow the refrigerant.

In the above electrode tip, the supporting portion may support the inner surface of the tip plate portion during welding of the work.

According to such a configuration, the support portion can receive the load acting on the tip plate portion during welding, so that it is possible to effectively suppress the deformation of the tip plate portion and reduce the thickness of the tip plate portion. it can.

In the above electrode tip, the supporting portion extends in a proximal direction from a proximal end of the inner tubular portion, and a portion of the supporting portion extending toward the proximal end side from the inner tubular portion is a resistor. You may function as a positioning part which positions the said refrigerant pipe so that the internal hole of the refrigerant pipe of a welding machine may connect to the said 1st flow path.

With such a configuration, when the electrode tip is mounted on the shank of the resistance welding machine, the refrigerant pipe can be easily positioned at a predetermined position of the electrode tip.

In the above electrode tip, the inner surface of the distal end portion of the inner cylindrical portion may be reduced in diameter in the distal end direction.

According to such a configuration, the center portion of the tip plate portion, on which a relatively large load is applied during welding, can be supported by the inner tubular portion, so that the tip plate portion can be suppressed more effectively while suppressing deformation of the tip plate portion. It is possible to reduce the thickness of the plate portion.

In the above electrode chip, the electrode chip may be configured by bonding a plurality of flat plate pieces to each other in a state of being stacked in the axial direction.

With such a configuration, it is possible to easily manufacture the electrode chip in which the first flow path, the second flow path, and the communication hole are formed.

In the above electrode tip, the inner cylinder portion may be joined to an inner surface of the tip plate portion.

With such a configuration, it is possible to reliably receive the load (pressure) applied to the tip plate portion during welding.

In the above electrode tip, the thickness of the central portion of the tip plate portion may be smaller than the thickness of the outer tubular portion.

With such a configuration, the tip plate portion can be effectively thinned.

In the above electrode tip, the communication hole may be opened in the tip end surface of the inner cylindrical portion.

According to such a configuration, the coolant guided from the first flow path can be efficiently brought into contact with the inner surface of the tip plate portion, so that the outer surface of the tip plate portion can be cooled more effectively.

According to the present invention, since the load (pressurizing force) applied to the tip plate portion during welding can be received by the inner tube portion supported by the outer tube portion via the support portion, deformation of the tip plate portion is suppressed. It is possible to reduce the thickness of the tip plate portion. Further, since the inner surface of the tip plate portion is cooled by the refrigerant, the outer surface of the tip plate portion can be effectively cooled.

It is a partially omitted block diagram of a resistance welding machine in which the electrode tip according to the present invention is used. FIG. 3 is a partially omitted vertical cross-sectional view of a state in which the electrode tip according to the first embodiment of the present invention is attached to a shank. 3A is a cross-sectional view taken along line IIIA-IIIA of FIG. 2, FIG. 3B is a cross-sectional view taken along line IIIB-IIIB of FIG. 2, and FIG. 3C is taken along line IIIC-IIIC of FIG. FIG. FIG. 6 is a partially omitted vertical cross-sectional perspective view of a state in which an electrode tip according to a second embodiment of the present invention is attached to a shank. 5A is a plan view of a first flat plate piece of the electrode chip of FIG. 4, FIG. 5B is a plan view of a second flat plate piece of the electrode chip of FIG. 4, and FIG. 5C is a third flat plate of the electrode chip of FIG. 5D is a plan view of a fourth flat plate piece of the electrode chip of FIG. 4, FIG. 5E is a plan view of a fifth flat plate piece of the electrode chip of FIG. 4, and FIG. 5G is a plan view of a sixth flat plate piece of the electrode chip of FIG. 5, and FIG. 5G is a plan view of a seventh flat plate piece of the electrode chip of FIG. 4. FIG. 5 is a first explanatory diagram showing the method of manufacturing the electrode chip shown in FIG. 4. FIG. 5 is a second explanatory view showing the method of manufacturing the electrode chip shown in FIG. 4.

Hereinafter, the electrode tip according to the present invention will be described with reference to the accompanying drawings by exemplifying preferred embodiments in relation to a resistance welding machine in which the electrode tip is used.

(First embodiment)
As shown in FIG. 1, the resistance welding machine 12 according to the present embodiment is for performing spot resistance welding on a work W, and is a welding gun supported by a wrist portion 16 constituting a robot arm 14. 18 and a pair of electrode tips 10A that can be attached to and detached from the welding gun 18. The work W is configured by stacking a plurality of plate materials 200, for example.

The welding gun 18 is a so-called C-type welding gun, and includes a gun body 20, a connecting rod 22 extending in one direction from the gun body 20, and a substantially C-shaped fixed arm 24 provided on the gun body 20. Have. The connecting rod 22 is displaced in the extending direction by the action of a drive source (not shown). A shank 26 to which the electrode tip 10A can be attached is provided at each of the tip of the connecting rod 22 and the tip of the fixed arm 24. The welding gun 18 may be a so-called X-type welding gun.

As shown in FIG. 2, the shank 26 has a cylindrical shape, and a refrigerant pipe 28 is arranged in its inner hole. The refrigerant pipe 28 is a tube through which a refrigerant such as cooling water flows, and is made of, for example, a resin material. That is, the inner hole of the refrigerant pipe 28 functions as the refrigerant supply passage 30 that supplies the refrigerant to the electrode chip 10A. Between the outer peripheral surface of the refrigerant pipe 28 and the inner peripheral surface of the shank 26, a clearance through which a refrigerant can flow is formed, and this clearance serves as a refrigerant discharge path 32 for discharging the refrigerant from the electrode tip 10A. .. The refrigerant pipe 28 extends in the tip direction from the tip of the shank 26. The outer peripheral surface 31 of the tip portion 27 of the shank 26 is tapered toward the tip.

In FIG. 1, the pair of electrode tips 10</b>A extend in the extending direction of the connecting rod 22 (the plate thickness direction of the work W) and the tips thereof face each other in a state of being attached to the shank 26.

As shown in FIG. 2, the electrode tip 10A is an electrode tip for resistance welding and is made of a conductive material. As the conductive material, for example, a metal material such as copper is used. More specifically, a copper alloy such as alumina-dispersed copper or chromium copper is often used as the conductive material. The electrode chip 10A is formed in a columnar shape and has a coolant channel 40 formed therein. A recess 42 into which the tip 27 of the shank 26 is fitted is formed on the base end surface 11 of the electrode tip 10A. The peripheral wall surface 41 forming the recess 42 is tapered in diameter toward the tip. The taper angle of the peripheral wall surface 41 of the recess 42 is set to be the same as the taper angle of the outer peripheral surface 31 of the tip portion 27 of the shank 26.

As shown in FIGS. 2 and 3A to 3C, in the electrode chip 10A, the refrigerant flows between the inner cylinder portion 46 in which the first flow path 44 through which the refrigerant flows is formed and the inner cylinder portion 46. The outer tubular portion 50 arranged on the outer peripheral side of the inner tubular portion 46 so as to form the second flow path 48 and the workpiece W at the time of welding are provided so as to close the opening on the tip side of the outer tubular portion 50. The front end plate portion 52 is in contact with, and a plurality of (four in the illustrated example) support portions 54 that connect the outer peripheral surface of the inner cylindrical portion 46 and the inner peripheral surface of the outer cylindrical portion 50 to each other.

In FIG. 2, the inner tubular portion 46 is provided coaxially with the outer tubular portion 50. However, the axis of the inner cylinder part 46 may be offset with respect to the axis of the outer cylinder part 50. The inner cylinder portion 46 extends from the tip end side of the bottom surface 43 of the recess 42 to the inner surface 53 of the tip plate portion 52.

That is, the base end surface 47 of the inner cylinder portion 46 is in contact with the tip end surface 29 of the refrigerant pipe 28 with the electrode tip 10A mounted on the shank 26 (see FIG. 2). The tip surface 49 of the inner cylinder portion 46 is in contact with the inner surface 53 of the tip plate portion 52. The inner diameter and outer diameter of the inner tubular portion 46 on the tip side are reduced toward the tip. Therefore, the tip surface 49 of the inner tubular portion 46 is in contact with the vicinity of the center of the inner surface 53 of the tip plate portion 52.

The tip surface 49 of the inner cylinder portion 46 is in contact with and joined to the inner surface 53 of the tip plate portion 52. That is, the tip surface 49 of the inner cylinder portion 46 supports the inner surface 53 of the tip plate portion 52. However, the front end surface 49 of the inner cylinder portion 46 may be in contact with the inner surface 53 of the front end plate portion 52 without being joined. Further, the tip surface 49 of the inner cylinder portion 46 is separated from the inner surface 53 of the tip plate portion 52 when the work W is not welded (in a state where no pressure is applied to the work W by the electrode tip 10A), The inner surface 53 of the tip plate portion 52 may be brought into contact with the W welding (in a state where a pressure force is applied to the work W by the electrode tip 10A). That is, the inner cylinder portion 46 may contact the inner surface 53 of the tip plate portion 52 during welding of the work W and can support the tip plate portion 52.

A concave portion 42 is formed in the base end portion 51 of the outer tubular portion 50. That is, the base end surface 59 of the outer tubular portion 50 is located closer to the base end direction than the base end surface 47 of the inner tubular portion 46. As shown in FIG. 3B, the plurality of support portions 54 are provided at equal intervals in the circumferential direction of the inner tubular portion 46 (positions that are out of phase by 90° in the illustrated example). Each support portion 54 extends from the tip end surface 49 of the inner tubular portion 46 to a space between the base end surface 47 of the inner tubular portion 46 and the base end surface 59 of the outer tubular portion 50 (see FIG. 2 ).

2 and 3C, the tip of the refrigerant pipe 28 is inserted into the space inside the positioning portion 56, which is a portion of each support portion 54 that extends in the proximal direction from the inner tubular portion 46. That is, the positioning part 56 positions the refrigerant tube 28 so that the inner hole (refrigerant supply path 30) of the refrigerant tube 28 communicates with the first flow path 44.

As shown in FIG. 2, the tip surface 57 of each support portion 54 is in contact with and joined to the inner surface 53 of the tip plate portion 52. That is, each support portion 54 supports the inner surface 53 of the tip plate portion 52. However, the tip surface 57 of each support portion 54 may be in contact with the inner surface 53 of the tip plate portion 52 without being joined. Further, the tip surface 57 of each support portion 54 may be separated from the inner surface 53 of the tip plate portion 52 when the work W is not welded, and may contact the inner surface 53 of the tip plate portion 52 when the work W is welded. That is, the support portion 54 may contact the inner surface 53 of the tip plate portion 52 during welding of the work W and can support the tip plate portion 52.

The outer surface 55 of the tip plate portion 52 is curved in a spherical shape and contacts the work W during welding. In the present embodiment, in order to effectively cool the outer surface 55 of the tip plate portion 52, the thickness of the central portion of the tip plate portion 52 is made thinner than the thickness of the outer tubular portion 50. Specifically, the plate thickness of the central portion of the tip plate portion 52 is preferably 1.0 mm or more and 2.0 mm or less, and more preferably 1.5 mm. However, in order to increase the rigidity of the central part of the tip plate part 52, the plate thickness of the center part of the tip plate part 52 may be thicker than 2.0 mm, or may be the plate thickness of the outer cylinder part 50 or more. Good.

The first flow path 44 is one hole extending over the entire length of the inner cylinder portion 46, and communicates with the refrigerant supply path 30 at the base end of the inner cylinder portion 46. 3A and 3B, a plurality of (four in the illustrated example) second flow paths 48 are provided at equal intervals in the circumferential direction of the inner tubular portion 46 (positions that are 90° out of phase in the illustrated example). .. That is, the second flow paths 48 that are adjacent to each other in the circumferential direction of the inner tubular portion 46 are partitioned by the support portion 54. As shown in FIG. 2, each second flow path 48 extends in the axial direction over the entire length of the support portion 54. Each second flow passage 48 communicates with the refrigerant discharge passage 32 at the base end of the inner cylinder portion 46.

A plurality of (four in FIG. 3A) communication holes 58 that communicate the first flow path 44 and the respective second flow paths 48 with each other are formed at the tip of the inner tubular portion 46. In FIG. 3A, the plurality of communication holes 58 are provided at equal intervals in the circumferential direction of the inner cylinder portion 46 (positions that are out of phase by 90° in the illustrated example). Specifically, the communication holes 58 are formed in the inner tubular portion 46 at positions between the support portions 54 that are adjacent to each other in the circumferential direction. In other words, each communication hole 58 is formed in a portion of the inner tubular portion 46 to which the support portion 54 is not connected, as viewed in the axial direction of the electrode tip 10A. Each communication hole 58 is open at the tip surface 49 of the inner tubular portion 46.

In the electrode chip 10A, the first flow path 44, the plurality of communication holes 58, and the plurality of second flow paths 48 form a coolant flow path 40 for cooling the outer surface 55 of the tip plate portion 52.

The electrode chip 10A according to the present embodiment is basically configured as described above, and next, the usage method thereof will be described.

As shown in FIG. 1, when the workpiece W is spot resistance welded, the user mounts one electrode tip 10A on the shank 26 provided at the tip of the connecting rod 22 and attaches the other electrode tip 10A to the fixed arm 24. It is attached to the shank 26 provided at the tip. At this time, as shown in FIG. 2, when the tip portion 27 of the shank 26 is fitted into the recess 42 at the base end of the outer tubular portion 50, the tip portion of the refrigerant pipe 28 is inserted into the space inside the plurality of positioning portions 56. It Then, the coolant is supplied to the coolant supply path 30 by a pump (not shown).

Then, as indicated by the one-dot chain line arrow in FIG. 2, the coolant in the coolant supply passage 30 flows through the first flow path 44 of the electrode chip 10A from the proximal end to the distal end, and reaches the inner surface 53 of the distal end plate portion 52. Contact. As a result, the inner surface 53 of the tip plate portion 52 is cooled by the refrigerant, so that the outer surface 55 of the tip plate portion 52 is cooled.

The refrigerant that has come into contact with the inner surface 53 of the tip plate portion 52 is guided to each second flow path 48 through each communication hole 58 and flows through each second flow path 48 from the tip to the base end of the electrode chip 10A. .. Then, the refrigerant flowing through each of the second flow paths 48 is guided to the refrigerant discharge path 32 via the recess 42, cooled by a heat exchanger (not shown), and then circulated to the refrigerant supply path 30 by the above-described pump. ..

Further, the robot arm 14 is moved so that the work W is located between the pair of electrode tips 10A. Then, by extending the connecting rod 22 from the gun body 20, the work W is held by the pair of electrode tips 10A. That is, the work W is subjected to a pressing force by the pair of electrode tips 10A. After that, by applying a voltage between the pair of electrode tips 10A, Joule heat is generated in the work W to perform resistance welding. When the resistance welding of the work W is completed, the connecting rod 22 is retracted toward the gun body 20 to separate the pair of electrode tips 10A from the work W.

Next, the function and effect of this embodiment will be described below.

In the present embodiment, the outer peripheral surface of the inner tubular portion 46 and the inner peripheral surface of the outer tubular portion 50 are connected to each other by the support portion 54, and the inner tubular portion 46 holds the inner surface 53 of the tip plate portion 52 during welding of the workpiece W. I support you. Thus, the inner cylinder portion 46 supported by the outer cylinder portion 50 via the support portion 54 can receive the load (pressure) applied to the tip plate portion 52 during welding, and thus the tip plate portion 52 is deformed. It is possible to reduce the thickness of the tip plate portion 52 while suppressing the above. Further, since the communication hole 58 that communicates the first flow path 44 and the second flow path 48 with each other is formed at the tip end portion of the inner cylinder portion 46, the tip plate from the first flow path 44 through the communication hole 58. The refrigerant guided to the inner surface 53 of the portion 52 can escape to the second flow path 48. Therefore, since the inner surface 53 of the tip plate portion 52 is cooled by the refrigerant, the outer surface 55 of the tip plate portion 52 can be effectively cooled.

Since the plurality of support portions 54 are provided so as to be spaced apart from each other in the circumferential direction of the inner tubular portion 46, the inner tubular portion 46 can be firmly supported by the outer tubular portion 50 by the plurality of support portions 54. Further, since the communication hole 58 is formed at a position between the support portions 54 adjacent to each other in the circumferential direction of the inner tubular portion 46, the support portion 54 becomes a resistance when the refrigerant flows through the communication hole 58. This can be suppressed, and the refrigerant can be circulated smoothly.

The support portion 54 supports the inner surface 53 of the tip plate portion 52 when welding the work W. Accordingly, the supporting portion 54 can receive the load applied to the tip plate portion 52 during welding, and thus the tip plate portion 52 can be thinned while effectively suppressing the deformation of the tip plate portion 52. ..

Since the portion of the support portion 54 that extends toward the base end side of the inner tubular portion 46 functions as the positioning portion 56, when the electrode tip 10A is attached to the shank 26 of the resistance welding machine 12, the refrigerant pipe 28 is connected to the electrode. The chip 10A can be easily positioned at a predetermined position.

Since the inner surface of the tip portion of the inner tubular portion 46 is reduced in diameter in the tip direction, the inner tubular portion 46 can support the central portion of the tip plate portion 52 on which a relatively large load acts during welding. it can. Therefore, it is possible to reduce the thickness of the tip plate portion 52 while suppressing the deformation of the tip plate portion 52 more effectively.

The inner cylinder portion 46 is joined to the inner surface 53 of the tip plate portion 52. Thereby, the load (pressurizing force) applied to the tip plate portion 52 during welding can be surely received.

Since the thickness of the central portion of the tip plate portion 52 is smaller than the thickness of the outer cylinder portion 50, the tip plate portion 52 can be effectively thinned. The communication hole 58 is open at the tip surface 49 of the inner tubular portion 46. With this, the coolant guided from the first flow path 44 can be efficiently brought into contact with the inner surface 53 of the tip plate portion 52, so that the outer surface of the tip plate portion 52 can be cooled more effectively.

The present embodiment is not limited to the above-mentioned configuration. In the electrode chip 10A, the inner hole of the refrigerant tube 28 may function as a refrigerant discharge path, and the space between the outer peripheral surface of the refrigerant tube 28 and the inner peripheral surface of the shank 26 may function as a refrigerant supply path. The same applies to the electrode chip 10B according to the second embodiment described later. Further, in the above example, the outer peripheral surface 31 of the tip portion 27 of the shank 26 is fitted to the peripheral wall surface 41 of the recess 42 of the electrode tip 10A, but the base end portion 51 of the outer tubular portion 50 of the electrode tip 10A is You may fit in the inner peripheral surface of the front-end|tip part 27 of the shank 26. The same applies to the electrode chip 10B according to the second embodiment described later.

(Second embodiment)
Next, an electrode chip 10B according to the second embodiment of the present invention will be described. In the electrode chip 10B according to the second embodiment, the same components as those of the electrode chip 10A described in the first embodiment described above are designated by the same reference numerals, and detailed description thereof will be omitted. ..

The electrode tip 10B according to this embodiment is used in the resistance welding machine 12 shown in FIG. 1 and can be attached to and detached from the shank 26. As shown in FIG. 4, the electrode tip 10B is made of the same conductive material as the electrode tip 10A. A cylindrical base portion 60 that constitutes the base end portion of the electrode tip 10B and a tip body 62 provided at the tip of the base portion 60 are provided.

The chip body 62 is configured by bonding a plurality of flat plate pieces 64 to each other in a state of being stacked in the axial direction of the electrode chip 10B. The plurality of flat plate pieces 64 include first to seventh flat plate pieces 64a to 64g.

Specifically, as shown in FIGS. 4 and 5A to 5G, the tip body 62 includes a first flat plate piece 64a, a second flat plate piece 64b, a third flat plate piece 64c, and a fourth flat plate from the tip direction in the tip portion. The piece 64d, the fifth plate piece 64e, the sixth plate piece 64f, and the seventh plate piece 64g are laminated one by one in this order, and the sixth plate piece 64f is located in the intermediate portion closer to the base end than the seventh plate piece 64g. And a seventh flat plate piece 64g are alternately laminated, and a plurality of seventh flat plate pieces 64g (two in the illustrated example) are laminated at the base end portion. Each of the first to seventh flat plate pieces 64a to 64g is formed in a circular shape in a plan view (see FIGS. 5A to 5G).

As shown in FIG. 5A, the outer surface 55 of the first flat plate piece 64a serving as the tip plate portion 52 is a portion where the workpiece W comes into contact and surrounds the spherical surface 66 provided in the central portion and the spherical surface 66 in an annular shape. And a curved surface 68 having a radius of curvature smaller than that of the spherical surface 66. In this embodiment, as understood from FIG. 4, in order to give the first flat plate piece 64a an appropriate rigidity, the plate thickness of the central portion of the first flat plate piece 64a is set to the second to seventh flat plates described later. It is formed thicker than the plate thickness of each of the pieces 64b to 64g. However, from the viewpoint of improving the cooling efficiency of the outer surface 55 of the first flat plate piece 64a, the plate thickness of the central portion of the first flat plate piece 64a is equal to or less than the thickness of each of the second to seventh flat plate pieces 64b to 64g. It may be formed in the height. It should be noted that any one of the first to seventh flat plate pieces 64a to 64g may be changed, for example, the first flat plate piece 64a may be made different from the other second to seventh flat plate pieces 64b to 64g. ..

As shown in FIG. 5B, in the second flat plate piece 64b, a circular first hole portion 70a formed in the central portion and an outer circumferential side of the first hole portion 70a are equally spaced in the circumferential direction (in 90° phase increments). A plurality (four in the illustrated example) of the second holes 72a provided at different positions, and a plurality (four in the illustrated example) of the first hole 70a and the second holes 72a communicating with each other. Slits 74a are formed. The second hole 72a is formed so that the width in the circumferential direction increases from the slit 74a toward the outside in the radial direction of the second flat plate piece 64b.

The second flat plate piece 64b has an annular outer peripheral portion 76a provided on the outer peripheral side of the plurality of second hole portions 72a, and a plurality of (four in the illustrated example) protrusions radially inward from the outer peripheral portion 76a. It has a portion 78a and a plurality of (four in the illustrated example) hole forming portions 80a which are provided at the tip of each protruding portion 78a and constitute the first hole portion 70a.

The protrusion 78a is located between the second holes 72a that are adjacent to each other in the circumferential direction. In other words, the protrusions 78a are provided at equal intervals in the circumferential direction of the outer peripheral portion 76a (positions that are out of phase by 90° in the illustrated example).

As shown in FIG. 5C, the third flat plate piece 64c has the same configuration as the second flat plate piece 64b. Therefore, in the third flat plate piece 64c, components similar to those of the second flat plate piece 64b are denoted by the same reference numerals but different alphabetical characters instead of a, and detailed description thereof will be omitted. The same applies to the fourth to seventh flat plate pieces 64d to 64g.

The third flat plate piece 64c is formed with a first hole 70b, a plurality of second holes 72b, and a plurality of slits 74b. The first hole 70b is one size larger than the first hole 70a, the second hole 72b is one size larger than the second hole 72a, and the slit 74b is formed wider than the slit 74a. Further, the third flat plate piece 64c has an outer peripheral portion 76b, a plurality of protruding portions 78b, and a plurality of hole forming portions 80b.

As shown in FIG. 5D, the fourth flat plate piece 64d is provided with a first hole 70c, a plurality of second holes 72c, and a plurality of slits 74c. The first hole 70c is one size larger than the first hole 70b, the second hole 72c is one size larger than the second hole 72b, and the slit 74c is formed wider than the slit 74b. Further, the fourth flat plate piece 64d has an outer peripheral portion 76c, a plurality of protruding portions 78c, and a plurality of hole forming portions 80c. An uneven portion 82 for increasing the heat exchange area with the refrigerant is provided on the inner surface of the outer peripheral portion 76c forming each second hole 72c. The concavo-convex shape portion 82 has concave portions and convex portions extending over the entire length in the thickness direction of the fourth flat plate piece 64d, which are alternately provided in the circumferential direction. However, it is needless to say that the uneven portion 82 can adopt any shape as long as the heat exchange area can be increased.

As shown in FIG. 5E, the fifth flat plate piece 64e is provided with a first hole portion 70d, a plurality of second hole portions 72d, and a plurality of slits 74d. The first hole 70d is one size larger than the first hole 70c, the second hole 72d is one size larger than the second hole 72c, and the slit 74d is formed wider than the slit 74c. Further, the fifth flat plate piece 64e has an outer peripheral portion 76d, a plurality of protruding portions 78d, and a plurality of hole forming portions 80d. A concave-convex shaped portion 82 is provided on the inner peripheral surface of the outer peripheral portion 76d forming each second hole portion 72d.

As shown in FIG. 5F, the sixth flat plate piece 64f is provided with a first hole 70e and a plurality of second holes 72e. The first hole 70e is one size larger than the first hole 70d, and the second hole 72e is one size larger than the second hole 72d. The sixth flat plate piece 64f has an outer peripheral portion 76e, a plurality of protruding portions 78e, and an annular hole forming portion 80e. The uneven portion 82 is provided on the inner peripheral surface of the outer peripheral portion 76e that constitutes each second hole portion 72e.

As shown in FIG. 5G, the seventh flat plate piece 64g is provided with a first hole 70f, a plurality of second holes 72f, and a plurality of slits 74e. The first hole 70f is one size larger than the first hole 70e, the second hole 72f is one size larger than the second hole 72e, and the slit 74e is wider than the slit 74d. The seventh flat plate piece 64g has an outer peripheral portion 76f, a plurality of protruding portions 78f, and a plurality of hole forming portions 80f. A concave-convex portion 82 is provided on the inner peripheral surface of the outer peripheral portion 76f forming each second hole portion 72f.

In such an electrode chip 10B, as shown in FIG. 4, the tip plate portion 52 is constituted by the first flat plate piece 64a, and the inner cylindrical portion is constituted by the hole forming portions 80a-80f of the second to seventh flat plate pieces 64b-64g. 46, the outer cylindrical portion 50 is configured by the outer peripheral portions 76a to 76f of the second to seventh flat plate pieces 64b to 64g and the base portion 60, and the protruding portions 78a of the second to seventh flat plate pieces 64b to 64g. A plurality of support parts 54 are constituted by ~78f. Moreover, the 1st flow path 44 is formed by each 1st hole part 70a-70f of the 2nd-7th flat plate pieces 64b-64g, and each 2nd hole part 72a-72f of the 2nd-7th flat plate pieces 64b-64g. The second flow path 48 is thus formed. Further, the communication holes 58 are formed by the slits 74a to 74d of the second to fifth flat plate pieces 64b to 64e.

That is, in the electrode chip 10</b>B, the inner tubular portion 46 in which the first fluid passage 44 through which the refrigerant flows is formed, and the second fluid passage 48 through which the refrigerant flows is formed between the inner tubular portion 46. An outer tubular portion 50 disposed on the outer peripheral side of the inner tubular portion 46, and a tip plate portion 52 that is provided so as to close the opening portion on the tip end side of the outer tubular portion 50 and abuts the work W during welding. A plurality of supporting portions 54 that connect the outer peripheral surface of the tubular portion 46 and the inner peripheral surface of the outer tubular portion 50 to each other are provided. A plurality of intermediate communication holes 84 formed by the slits 74e of the seventh flat plate piece 64g are formed in the intermediate portion of the inner tubular portion 46. The intermediate communication hole 84 communicates the first flow path 44 and the second flow path 48 with each other.

Further, in the protruding portions 78f of the plurality of (two in the illustrated example) seventh flat plate pieces 64g provided at the base end portion of the chip body 62, the inner hole (refrigerant supply passage 30) of the refrigerant pipe 28 is the first. It functions as a positioning portion 56 that positions the refrigerant pipe 28 so as to communicate with the flow path 44.

The electrode chip 10B according to this embodiment is basically configured as described above, and a method of manufacturing the electrode chip 10B will be described next. As shown in FIG. 6, in the case of manufacturing the electrode chip 10B, in the preparation process, the first to seventh flat plates 100a to 100g made of metal such as copper in the number corresponding to the number of the flat plate pieces 64 forming the chip body 62. To prepare. In the present embodiment, the first to fifth flat plates 100a to 100e are prepared one by one, and the sixth flat plate 100f and the seventh flat plate 100g are prepared plural by one.

Subsequently, in the processing step, predetermined processing is performed on each of the first to seventh flat plates 100a to 100g. In this processing step, for example, the first to seventh flat plates 100a to 100g are cut by pressing, laser processing, or the like.

A plurality of first processed portions 102a corresponding to the first flat plate pieces 64a are formed on the first flat plate 100a. Each first processing portion 102a has a plurality (two in the illustrated example) of arc-shaped outer peripheral cutting portions 104 provided on the same circumference. The plurality of outer peripheral cutting portions 104 are not connected to each other. That is, the first circular portion 106 a located inside the outer peripheral cutting portion 104 is connected to the outer frame portion 108 of the first flat plate 100 a via the plurality of connecting portions 105.

A plurality of second processed portions 102b corresponding to the second flat plate pieces 64b are formed on the second flat plate 100b. Each second processed portion 102b has a plurality of outer peripheral cutting portions 104, and the second circular portion 106b located inside the outer peripheral cutting portion 104 has a plurality of first hole portions 70a of the second flat plate piece 64b and a plurality of plural outer peripheral cutting portions 104b. The second hole 72a and the plurality of slits 74a are formed.

A plurality of third processed portions 102c corresponding to the third flat plate pieces 64c are formed on the third flat plate 100c. Each third processed portion 102c has a plurality of outer peripheral cutting portions 104, and the third circular portion 106c located inside the outer peripheral cutting portion 104 has a plurality of first hole portions 70b of the third flat plate piece 64c and a plurality of plural outer peripheral cutting portions 104c. The second hole 72b and the plurality of slits 74b are formed.

A plurality of fourth processed portions 102d corresponding to the fourth flat plate pieces 64d are formed on the fourth flat plate 100d. Each of the fourth processed portions 102d has a plurality of outer peripheral cutting portions 104, and the fourth circular portion 106d located inside the outer peripheral cutting portion 104 has a plurality of first hole portions 70c of the fourth flat plate piece 64d and a plurality of plural outer peripheral cutting portions 104d. The second hole 72c and the plurality of slits 74c are formed.

A plurality of fifth processed portions 102e corresponding to the fifth flat plate pieces 64e are formed on the fifth flat plate 100e. Each of the fifth processed portions 102e has a plurality of outer peripheral cutting portions 104, and the fifth circular portion 106e located inside the outer peripheral cutting portion 104 has a plurality of first hole portions 70d of the fifth flat plate piece 64e and a plurality of plural outer peripheral cutting portions 104e. The second hole 72d and the plurality of slits 74d are formed.

A plurality of sixth processed portions 102f corresponding to the sixth flat plate pieces 64f are formed on each sixth flat plate 100f. Each of the sixth processed portions 102f has a plurality of outer peripheral cutting portions 104, and the sixth circular portion 106f located inside the outer peripheral cutting portion 104 has a plurality of first hole portions 70e of the sixth flat plate piece 64f and a plurality of plural outer peripheral cutting portions 104f. The second hole 72e is formed.

A plurality of seventh processed portions 102g corresponding to the seventh flat plate pieces 64g are formed on each of the seventh flat plates 100g. Each of the seventh processed portions 102g has a plurality of outer peripheral cutting portions 104, and the seventh circular portion 106g located inside the outer peripheral cutting portion 104 has a plurality of first hole portions 70f of the seventh flat plate piece 64g and a plurality of plural outer peripheral cutting portions 104g. The second hole 72f and the plurality of slits 74e are formed.

After the processing step, in the stacking step, a predetermined number of the first to seventh flat plates 100a to 100g are stacked in a predetermined order. Then, in the bonding step, the stacked first to seventh flat plates 100a to 100g are diffusion bonded to each other. As a result, the first to seventh circular portions 106a to 106g are joined to each other. In the bonding step, the base portion 60 of the electrode chip 10B may be diffusion bonded to the seventh flat plate 100g located at the most proximal end. However, the base portion 60 may be joined to the chip body 62 in another step after the chip body 62 is manufactured. The joining method in the joining step is not limited to diffusion joining, and may be joining by various kinds of welding, brazing, adhesive or the like as long as load resistance, electrical conductivity and thermal conductivity are secured.

After the joining step, in the cutting step, the connecting portions 105 of the first to seventh flat plates 100a to 100g are cut by punching or the like so that the outer peripheral cutting portions 104 are connected to each other. As a result, the first to seventh circular portions 106a to 106g are separated from the outer frame portion 108 of the first to seventh flat plates 100a to 100g, and the columnar laminated assembly 120 is formed (see FIG. 7).

After the cutting step, in the finishing step, the tip end portion of the laminated joined body 120 is spherically cut along the two-dot chain line in FIG. 7 and the outer peripheral surface 63 of the circular hole 61 provided in the base portion 60 is tapered. By cutting into a shape, the electrode chip 10B in which the spherical surface 66, the curved surface 68, and the peripheral wall surface 41 of the recess 42 are formed is manufactured.

The present embodiment has the same effects as the above-described first embodiment. Further, since the electrode chip 10B is configured by joining a plurality of flat plate pieces 64 in a state of being stacked in the axial direction, the first flow path 44, the second flow path 48, and the communication hole 58 are formed. The electrode chip 10B formed inside can be easily manufactured.

The present embodiment is not limited to the above-mentioned configuration. In the present embodiment, the flat plate piece 64 exemplifies the configuration including the first to seventh flat plate pieces 64a to 64g, but the type and number of the flat plate pieces 64 can be appropriately changed.

The electrode chip according to the present invention is not limited to the above-described embodiment, and it goes without saying that various configurations can be adopted without departing from the gist of the present invention.

Claims (9)

An electrode tip (10A, 10B) for resistance welding,
An inner cylinder part (46) having a first flow path (44) through which a refrigerant flows formed therein;
An outer cylinder part (50) arranged on the outer peripheral side of the inner cylinder part (46) so that a second flow path (48) through which the refrigerant flows is formed between the inner cylinder part (46) and
A tip plate portion (52) which is provided so as to close the opening on the tip side of the outer tubular portion (50) and which abuts on the work (W) during welding;
A support part (54) for connecting the outer peripheral surface of the inner cylindrical part (46) and the inner peripheral surface of the outer cylindrical part (50) to each other;
The inner cylinder portion (46) supports the inner surface (53) of the tip plate portion (52) during welding of the work (W),
A communication hole (58) for communicating the first flow path (44) and the second flow path (48) with each other is formed at a tip portion of the inner cylinder part (46).
An electrode chip (10A, 10B) characterized by the above. The electrode tip (10A, 10B) according to claim 1,
A plurality of the support portions (54) are provided apart from each other in the circumferential direction of the inner tubular portion (46),
The communication hole (58) is formed at a position between the support portions (54) adjacent to each other in the circumferential direction of the inner tubular portion (46).
An electrode chip (10A, 10B) characterized by the above. The electrode chip (10A, 10B) according to claim 1 or 2,
The support portion (54) supports the inner surface (53) of the tip plate portion (52) during welding of the work (W),
An electrode chip (10A, 10B) characterized by the above. The electrode chip (10A, 10B) according to any one of claims 1 to 3,
The support portion (54) extends in the proximal direction from the proximal end of the inner tubular portion (46),
An inner hole of the refrigerant pipe (28) of the resistance welding machine communicates with the first flow path (44) in a portion of the support portion (54) extending toward the base end side of the inner tubular portion (46). Functioning as a positioning portion (56) for positioning the refrigerant pipe (28),
An electrode chip (10A, 10B) characterized by the above. The electrode chip (10A, 10B) according to any one of claims 1 to 4,
The inner surface of the tip portion of the inner tubular portion (46) is reduced in diameter in the tip direction.
An electrode chip (10A, 10B) characterized by the above. The electrode chip (10B) according to any one of claims 1 to 5,
The electrode chip (10B) is configured by bonding a plurality of flat plate pieces (64) to each other in a state of being stacked in the axial direction,
An electrode tip (10B) characterized by the above. The electrode chip (10A, 10B) according to any one of claims 1 to 6,
The inner cylinder portion (46) is joined to the inner surface (53) of the tip plate portion (52).
An electrode chip (10A, 10B) characterized by the above. In the electrode chip (10A, 10B) according to any one of claims 1 to 7,
The thickness of the central portion of the tip plate portion (52) is thinner than the thickness of the outer tubular portion (50),
An electrode chip (10A, 10B) characterized by the above. In the electrode tip (10A, 10B) according to any one of claims 1 to 8,
The communication hole (58) is open at the tip end surface (49) of the inner tubular portion (46).
An electrode chip (10A, 10B) characterized by the above.

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