WO2014087865A1

WO2014087865A1 - Cold welding die and wire rod

Info

Publication number: WO2014087865A1
Application number: PCT/JP2013/081620
Authority: WO
Inventors: 啓一郎岡; 達生川島; 和明廣田; 秋田　裕之
Original assignee: 三菱電機株式会社
Priority date: 2012-12-06
Filing date: 2013-11-25
Publication date: 2014-06-12
Also published as: JP2016027944A

Abstract

A cold welding die (1), which is provided with two paired dies (100, 101) configuring coil chucks (2) for gripping wire rods (11a, 11b) with paired die pieces (1a - 1d) and which joins the wire rods (11a, 11b) with each other by abutting the paired dies (100, 101) so that the wire rods (11a, 11b) gripped by the coil chucks (2) abut against each other. For the coil chucks (2), the inside diameter of the inner wall section (2a) of the portion for abutting the wire rods (11a, 11b) against each other is formed to be larger than the inside diameter of the bore section (2b) of the portion for gripping the wire rods (11a, 11b).

Description

Die and wire rod for cold welding

This invention relates to a die for cold pressure welding and a wire, in which a joined portion of the wire can obtain a sufficiently stable joining strength.

The cold welding method, which is one of the methods for connecting conventional wire rods, incorporates a die between both V blocks arranged on the upper part of the frame of the cold welding machine. Then, both the V blocks are pressed against each other by rotating a lever pivotally supported by the frame. Then, the cold-welded wire rod inserted between the dies is cold-welded. The die is composed of four die pieces, and a die hole is formed by gathering. The dice are incorporated into the V block so that the inclined surface of the die piece contacts the inclined surface of the V block. A wire rod is inserted into the die hole so that the end portions abut each other. When the connection work is started, the die is first pressed in the moving direction of the V block. Subsequently, the die slides along the inclined surface of the V block, and is also pressed in the axial direction of the die hole to compress the abutting surface of the wire (for example, see Patent Document 1). The conventional die used in the cold pressure welding machine as described above has a wire rod gripping portion at the center of the die, and a plurality of grooves perpendicular to the wire rod gripping portion are formed in the wire rod gripping portion to prevent the wire rod from slipping. (For example, refer to Patent Document 2).

JP-A-8-57662 Japanese Utility Model Publication No. 3-40470

Conventional dies used in general cold welding machines, such as the conventional cold welding dies and wires shown in Patent Document 1, usually have a die hole shape that matches the outer diameter of the wire. It is formed in a cylindrical shape. Therefore, if the outer diameter of the wire is smaller than that of the die hole, the wire slides, and if it is larger, the wire cannot enter the die hole, and if the shape of the die hole and the wire does not match, sufficient cold welding cannot be performed. It was.

In addition, it is considered that the conventional die shown in Patent Document 2 can absorb the variation in the outer diameter of the wire somewhat due to the groove provided in the wire holding portion. However, if the wire rods bite into the groove, the wire rod does not come off from the wire rod gripping portion and the wire rod cannot be fed, and there is a concern that cold welding cannot be performed sufficiently. Further, considering the variation in the conductor diameter of the actual wire and the variation in the insulation film thickness, there is a problem that the variation in the outer diameter of the wire cannot be sufficiently absorbed by the groove alone.

In addition, in both conventional dies and wires that are cold-welded with the dies, in addition to variations in the conductor diameter and insulation coating thickness of the wires, variations in the end face shape of each pair of wires that are connected by cold-welding There is. And in order to ensure the joint strength of a connection part, there existed a problem which requires careful attention for state management of a wire, such as finishing the end surface of a wire.

The present invention has been made to solve the above-described problems. Even when the outer diameter of the wire and the end face shape of the wire vary, the cold can obtain a sufficiently stable joint strength at the joined portion of the wire. An object of the present invention is to provide a cold pressure welding die and a wire rod capable of performing pressure welding.

The cold welding die of this invention is
Two pair dies constituting a coil chuck part that grips the wire rod with a pair of die pieces are provided, and the pair of dies are brought into contact with each other so that the wire rods gripped by the coil chuck portion are brought into contact with each other. In cold welding dies,
The coil chuck portion is formed so that a part or all of the inner diameter of the inner wall portion of the portion for contacting the wire rods is larger than the inner diameter of the inner diameter portion of the portion gripping the wire rod.

Moreover, the wire of this invention is
Wires joined by cold welding are
The cross-sectional area of the joint portion of the wire is formed larger than the cross-sectional area of the strand of the wire.

Since the cold pressure welding die and wire of the present invention are configured as shown above,
Even when the outer diameter of the wire and the end face shape of the wire vary, it is possible to perform cold pressure welding in which the joining portion of the wire can obtain sufficiently stable joining strength.

It is a perspective view which shows the structure of the die | dye for cold pressure welding of Embodiment 1 of this invention. It is a top view which shows the structure of the die for cold welding shown in FIG. It is sectional drawing which shows the structure of the die | dye for cold welding shown in FIG. It is sectional drawing which shows the structure of the die | dye for cold welding shown in FIG. It is explanatory drawing explaining operation | movement of the cold pressure welding die shown in FIG. It is a figure which shows the structure of the wire after cold-welding using the cold-welding die shown in FIG. It is a figure which shows the structure of the wire after cold-welding using the cold-welding die shown in FIG. It is a figure which shows the structure of the wire after cold-welding using the cold-welding die shown in FIG. It is sectional drawing which shows the structure of the die | dye for cold pressure welding in Embodiment 2 of this invention. It is sectional drawing which shows the structure of the die | dye for cold pressure welding in Embodiment 3 of this invention. It is a figure which shows the structure of the wire after cold pressure welding using the die | dye for cold pressure welding shown in FIG. It is sectional drawing which shows the structure of the other die | dye for cold pressure welding in Embodiment 3 of this invention. It is sectional drawing which shows the structure of the other die | dye for cold pressure welding in Embodiment 3 of this invention. It is sectional drawing which shows the structure of the cold pressure welding die and wire in Embodiment 4 of this invention. It is sectional drawing which shows the structure of the other die | dye for cold pressure welding in Embodiment 4 of this invention, and a wire. It is sectional drawing which shows the structure of the other die | dye for cold welding and wire in Embodiment 4 of this invention. It is sectional drawing which shows the structure of the die | dye for cold welding and wire in Embodiment 5 of this invention.

Embodiment 1 FIG.
Embodiments of the present invention will be described below. 1 is an exploded perspective view and a combined perspective view showing the structure of a cold pressure welding die according to Embodiment 1 of the present invention. FIG. 2 is a top view showing the configuration of the cold pressure welding die shown in FIG. 3 and 4 are cross-sectional views showing the cross-section in the XX direction in FIG. 2 of the configuration of the cold pressure welding die shown in FIG. FIG. 3 shows a state of the cold pressure welding die before inserting the wire. FIG. 4 shows a state of the cold pressure welding die after inserting the wire. 3 (b) and 3 (c) are enlarged cross-sectional views for explaining details of the coil chuck portion before insertion of wires b and c in FIG. 3 (a). FIGS. 4B and 4C are enlarged cross-sectional views for explaining details of the coil chuck portion and the wire after insertion of the wire at the positions b and c in FIG. 4A.

FIG. 5 is an explanatory diagram for explaining the operation when the wire is cold-welded in the cold-welding die shown in FIG. FIG. 6 is a diagram showing the configuration of the wire after the cold pressure welding is performed using the cold pressure welding die shown in FIG. FIG. 7 is a cross-sectional view showing a configuration of a wire material that does not have an insulating coating portion on the outer periphery before and after performing cold pressure welding using the cold pressure welding die shown in FIG. FIG. 8 is a cross-sectional view showing the configuration of a wire having an insulating coating portion on the outer periphery before and after performing cold pressure welding using the cold pressure welding die shown in FIG.

In the figure, a cold pressure welding die (hereinafter referred to as a die) 1 is composed of four die pieces 1a to 1d. The die piece 1a and the die piece 1b are paired to form a pair die 100. Further, the die piece 1c and the die piece 1d are paired to constitute a pair die 101. These two pair dies 100 and 101 are paired to form a die 1. The first wire 11a is held by the pair die 100. The second wire 11b is held by the pair die 101. The paired dies 100 and 101 are brought into contact with each other, so that the first wire 11a and the second wire 11b are pressed and joined to form the wire 11.

Groove portions 20 are provided on the mating surfaces 10 of the die piece 1a and the die piece 1b constituting the pair die 100, respectively. By combining the dice piece 1a and the dice piece 1b, the groove 20 constitutes the coil chuck portion 2 for gripping the first wire 11a. And in order to make insertion of the wire 11a into the coil chuck | zipper part 2 easy, the guide part 3 for wire insertion is formed. This guide part 3 is formed on the insertion opening side of the wire 11 of the coil chuck part 2. And the guide part 3 is formed so that it may spread in the taper shape toward the end surface of

die piece

1a, 1b.

Further, the coil chuck portion 2 is formed with an abutting portion 4 that abuts the first wire 11a on the pair die 100 side and the second wire 11b on the pair die 101 side. When the pair dies 100 and 101 are abutted and pressed, the abutment portions 4 of the coil chuck portions 2 of the pair dies 100 and 101 are abutted to press the two

wire rods

11a and 11b. Around the portion where the wire rods of the coil chuck portion 2 of the

die pieces

1a and 1b come into contact with each other, a burr storage portion 5 is provided to escape the burr 13 generated in the cold welding process of the first wire rod 11a. Yes. The burr storage portion 5 is formed in a tapered shape that decreases in size toward the coil chuck portion 2 side.

Next, details of the inner wall portion of the coil chuck portion 2 will be described (see FIGS. 3 and 4). The inner wall 2a (FIGS. 3 (c) and 4 (c)) where the wire rods of the coil chuck portion 2 come into contact with each other is arranged such that the outer portion of the first wire rod 11a does not come into contact therewith. It is formed larger than the size of the outer shape portion 11a. Here, as shown in FIG. 4C, the inner wall portion 2a is formed in a circular shape in which the diameter is larger than the diameter of the first wire 11a. Furthermore, the inner wall portion 2b (FIGS. 3B and 4B) other than the inner wall portion 2a of the portion for the wire rods of the coil chuck portion 2 to contact each other is a portion that contacts the outer shape portion of the first wire rod 11a. It is formed in a substantially elliptical shape having Z. Here, as shown in FIG. 4 (b), the diameter of the first wire 11a and the length of the inner wall 2b in the vertical direction are formed to be the same and have a portion Z that comes into contact therewith. Note that the configuration of the pair die 101 is the same as the configuration of the pair die 100 described above, and thus the description thereof is omitted as appropriate.

Next, the operation of the dice according to the first embodiment configured as described above will be described. First, the die 1 is disposed in a cold pressure welding machine similar to the conventional one. The dice pieces 1a to 1d are arranged in a state where the intervals are maintained. In this state, as shown in FIG. 5A, the wire 11 is inserted into the coil chuck portion 2 from the guide portion 3 side of each of the pair dies 100 and 101. Next, as shown in FIG. 5B, both sides of each of the die pieces 1a to 1d are pressed inward to move in the direction indicated by the arrow A in FIG. 5B. And the 1st wire 11a is settled in the coil chuck | zipper part 2 of the pair die | dye 100 comprised with the

die pieces

1a and 1b. Further, the second wire 11b is accommodated in the coil chuck portion 2 of the pair die 101 constituted by the

die pieces

1c and 1d. And each

wire

11a, 11b contact | abuts in the location Z of the inner wall part 2b. As a result, the coil chuck portion 2 holds each wire 11. At this time, the distance between the pair die 100 and the pair die 101 is maintained.

Next, as shown in FIG. 5C, the pair dies 100 and 101 are pressed inward (in the direction indicated by the arrow B in FIG. 5C), and the pair dies 100 and 101 are brought into contact with each other. Then, the two

wire rods

11a and 11b gripped by the coil chuck portions 2 of the pair dies 100 and 101 are compressed and joined. Then, a part of the joint portion of both the

compressed wires

11 a and 11 b becomes a burr 13 and is pushed out to the burr storage portion 5. Next, as shown in FIG. 5D, the

dice pieces

1a and 1d and the

dice pieces

1c and 1d of the paired dies 100 and 101 are separated from each other (the direction indicated by the arrow C in FIG. 5D).

These steps are repeated in multiple stages to discharge the oxide film / impurities at the junction of the wire 11 to the outside as burrs 13. This makes stable cold welding. Then, as shown in FIG. 6, the wire 11 connected by cold pressure welding through such a process is formed such that the cross-sectional area of the joint 110 of the wire 11 is larger than the cross-sectional area of the wire of the wire 11. ing. This is because the inner wall portion 2a of the portion where the wire rods of the butting portion 4 of the coil chuck portion 2 come into contact with each other is formed larger than the inner diameter of the inner wall portion 2b of the portion gripping both the

wire rods

11a and 11b. This is because the outer portions of 11a and 11b are formed larger than the size of the outer portions of both wires 11a so that they do not contact each other. This is because, in cold pressure welding, the joint portions of both

wires

11a and 11b are pressure-welded, and the stress diverges toward the inner wall 2a side where the outer portions of both

wires

11a and 11b are not in contact. Further, the joining part 110 is formed with a burr 13 having a joining area formed larger in cross-sectional area than that of the other joining part 110.

Next, another example of the wire 11 configured by cold welding using the die 1 of the first embodiment described above will be described. For example, the general wire 11 has a shape formed by only cylindrical conductors 121 having the same diameter as shown in FIGS. 7A and 7B before joining. After the joining, as shown in FIGS. 7C and 7D, the sectional area of the joining portion 110 of the wire 11 is formed larger than the sectional area of the strand of the wire 11.

Further, the wire 11 is formed of a conductor 121 such as copper or aluminum and an alloy mainly containing them, and the wire 11 is similarly applied to the case where the outer periphery of the conductor 121 is covered with the insulating coating portion 120. Be joined. For example, as shown in FIGS. 8A and 8B, the wire 11 has a shape that is formed of a cylinder having the same diameter before joining, but after joining, the wires 11 shown in FIGS. As shown in d), the cross-sectional area of the joint 110 of the wire 11 is formed larger than the cross-sectional area of the strand of the wire 11. 7 and 8 have been described as the wire 11, only the side corresponding to either the first wire 11 a or the second wire 11 b cut from the joint portion is shown. Furthermore, after joining, the state after the burr 13 is removed is shown.

According to the die and the wire in Embodiment 1 configured as described above, the inner diameter of the inner wall portion of the coil chuck portion where the wire rods come into contact with each other is larger than the inner diameter of the inner wall portion of the portion holding the wire rod. It is formed larger than this. For this reason, the inner diameter of the inner wall portion of the part for the wire rods to come into contact with each other is formed larger than the size of the outer shape portion of each wire rod so as not to contact the outer shape portion of each wire rod held by each coil chuck portion. Yes. Therefore, the wire after joining expands the cross-sectional area of the joint part from the cross-sectional area of the other part. Therefore, the cross-sectional area of the joint part of the wire can be made larger than the cross-sectional area of the other part of the wire. Thereby, the joint part of a wire can improve joint strength, and it becomes possible to ensure the reliability of the quality of a joint part.

In particular, in a line with a high connection frequency by cold welding, such as a motor manufacturing line, there are variations in the diameter of the wire material and variations in the thickness of the insulating coating part, etc. It is possible to prevent the occurrence of poor connection and contribute to the improvement of product quality. As described above, since cold welding with high accuracy and high productivity can be provided, the cold welding method can be employed with confidence in the motor production line.

Also, the joining of wire rods by the cold welding method is a joining method that uses metal bonding on the new metal surface (pure metal surface that has not been oxidized) by pressing, so it does not rely on stress as with connector terminals. . For example, aluminum is a metal that undergoes creep (stress relaxation) over time, and even if the aluminum wire is connected with a connector terminal, the pressed aluminum wire is deformed over time. For this reason, the stress of the connector terminal is released, and the electrical resistance of the connection portion is increased, which may cause a quality defect. On the other hand, in the cold welding, an aluminum wire can be reliably joined and connected. As described above, the die according to the first embodiment can employ the cold welding method in the motor production line. Therefore, even when an aluminum wire is used as the motor winding, the wire can be reliably connected and the quality can be improved. be able to.

Moreover, although the joint part of the wire formed like this Embodiment 1 expands, in the manufacturing process of the final product of joining the wound wire materials at the time of motor manufacture, this Embodiment 1 Such a deformation of the wire shape of the cold welded portion is not particularly problematic.

For example, in a wire production line, there is no wire connection process by cold welding during normal wire production. However, a wire connecting step by cold welding that connects the end of use of the feed material and the start of use of the feed material occurs only when the feed material is replaced. On the other hand, in a motor manufacturing line, for example, during normal motor manufacturing, a wire connecting process by cold welding that connects wires wound while being stretched at a plurality of locations for each work occurs. The die according to the first embodiment can be used in a line having a low connection frequency by cold welding, such as a wire production line, but particularly by being used in a motor production line having a high connection frequency by cold welding. More effective.

In addition, the joined portion of the wire and the portion where the wires of the coil chuck portion come into contact with each other are set according to conditions desired for the joined portion of the wire after joining. However, the effects of the first embodiment can be obtained if at least the above-described locations exist. This also applies to the following embodiments, and the description thereof will be omitted as appropriate.

Further, in the first embodiment, any wire material made of a material that can be cold-welded can be cold-welded. Further, even if the first and second wire rods that are cold-welded are different metal materials, the same effects as those of the first embodiment can be obtained. This also applies to the following embodiments, and the description thereof will be omitted as appropriate.

Embodiment 2. FIG.
In the first embodiment, only the inner wall portion of the portion for the wire rods of both pair dies of the coil chuck portion to contact each other is not in contact with the outer shape portion of each wire rod held by each coil chuck portion. The example which forms larger than the magnitude | size of the external part of a wire was shown. However, the present invention is not limited to this, and in the second embodiment, each of the inner wall portions of the coil chuck portion 2 does not contact the outer shape portion of each wire held by each coil chuck portion. The case where it forms larger than the magnitude | size of the external part of a wire is demonstrated.

FIG. 9 shows the structure of a die according to the second embodiment of the present invention. 9 is a cross-sectional view showing a cross-section in the XX direction in FIG. FIG. 9A shows the state before the wire is inserted. FIG.9 (b) shows after insertion of a wire. In the figure, the same parts as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted. The coil chuck portion 2 is formed such that the inner wall portion 2c is larger than the size of the outer portions of both

wires

11a and 11b so that the outer portions of both

wires

11a and 11b do not contact each other. However, in the case of the coil chuck portion 2 as described above, a holding portion (not shown) for holding both the

wires

11a and 11b is separately required.

According to the second embodiment configured as described above, by performing the same operation as in the first embodiment, the same effect can be obtained, and the shape of the coil chuck portion can be simplified. Manufacturing cost is reduced. Further, even when the diameter of the wire is slightly different, it can be dealt with. For this reason, it is not necessary to manufacture a dedicated die for each model of the product, and no setup change is required, which can contribute to improvement of productivity at the manufacturing site.

Embodiment 3 FIG.
In each said embodiment, the case where the wire 11 was provided with the insulating coating part 120 and the case where the insulating coating part 120 was not provided were demonstrated similarly. And the insulation film part 120 coat | covered with the wire 11 usually has slipperiness. Therefore, in order to perform the joining of the wire 11 by stable cold welding, it is desired that the wire 11 does not slip during the cold welding. In the third embodiment, a case where attention is paid to this will be described. In addition, in this Embodiment 3, although shown about the wire 11 provided with the insulating film part 120, it can implement similarly also in the wire 11 which is not provided with the insulating film part.

FIG. 10 shows the structure of a die according to the third embodiment of the present invention. 10 is a cross-sectional view showing a cross-section in the XX direction in FIG. Fig.10 (a) shows the state of the dice | dies before insertion of a wire. FIG.10 (b) shows the state of the dice | dies after insertion of a wire. In the figure, the same parts as those in the above embodiments are denoted by the same reference numerals, and description thereof is omitted. As for the inner wall part of the coil chuck part 2, the inner wall part 2d of the part for the wire rods of the coil chuck part 2 to contact each other is formed larger than the inner diameter of the inner wall part of the part holding the wire. Therefore, it is formed larger than the size of the outer portion of the first wire 11a so that the outer portions of both the

wires

11a and 11b do not contact each other. Further, the inner wall portion other than the inner wall portion 2d of the coil chuck portion 2 is larger than the size of the outer portions of the both

wires

11a and 11b so as not to contact the outer portion of the first wire 11a held by the coil chuck portion 2. The inner wall portion 2e as the first location formed and the inner wall portion 2f as the second location formed so as to have the location Z that contacts the outer shape portions of the two

wires

11a and 11b are alternately formed. Yes. That is, the inner wall portion 2e as the first portion of the portion that does not hold the first wire 11a or the second wire 11b, and the second portion of the portion that holds the first wire 11a or the second wire 11b. The inner wall portions 2f are alternately formed.

Here, the inner wall 2d and the inner wall 2e are formed in the same shape. Further, the size of the inner wall portion 2d at the second location is formed smaller than the size excluding the insulating coating portion 120 of both

wires

11a and 11b. Therefore, since the inner wall 2d of the second location is deeper than the thickness of each insulating coating 120 of both

wires

11a and 11b when the two

wires

11a and 11b are gripped by the coil chuck portion 2, the inner coating 2 It is formed to bite. However, the inner wall portion 2d of the second location is set to such an extent that when the two

wire rods

11a and 11b are gripped, the inner wall portion 2d bites into such an extent that the role of the insulating coating portion 120 can be fulfilled and is not broken. Is.

When cold welding is performed using the die 1 of the third embodiment configured as described above, the outer shape of the wire 11 is formed to have irregularities as shown in FIG. 11, for example.

According to the die of the third embodiment configured as described above, the same effect as that of each of the embodiments described above can be obtained, and the insulating film portion of the wire can be wedged by the second inner wall portion. The effect of inserting is generated, preventing the wire from slipping during cold welding.

Further, examples of the configuration of other dice in the third embodiment of the present invention are shown in FIGS. 12 is a cross-sectional view showing a cross-section in the XX direction in FIG. Fig.12 (a) shows the state of the dice | dies before insertion of a wire. FIG.12 (b) shows the state of the dice | dies after insertion of a wire. FIG. 13 is a cross-sectional view showing a cross-section in the XX direction in FIG. FIG. 13A shows the state of the dice before the wire is inserted. FIG.13 (b) shows the state of the dice | dies after insertion of a wire.

In the case shown in FIG. 10, the example is shown in which the

inner wall portions

2d and 2e formed larger than the size of the outer shape portions of both the

wires

11a and 11b are formed in the same concentric shape. This is not restrictive, and as shown in FIG. 12, the inner wall portion 2g of the portion for contacting the wire rods of the coil chuck portion 2 formed larger than the size of the outer shape portion of the first wire rod 11a, and The inner wall portion 2h of the first location is not enlarged in the same manner in all concentric circles, but can also be performed in the same way when a portion indicated by a substantially rectangular shape in the drawing is formed larger. Further, as shown in FIG. 13, the inner wall portion 2a of the portion for the wire rods of the coil chuck portion 2 to contact each other is formed, for example, in the same manner as in the first embodiment, and the other inner wall portions 2e and The two inner wall portions 2f can be formed in the same manner as in the third embodiment shown in FIG.

Embodiment 4 FIG.
Here, first, a case where the wire 11 covered with the insulating coating 120 is joined by cold welding will be described. An insulating coating 120 is interposed in the burr 13 generated by cold welding. For this reason, there is a possibility that the insulating coating 120 will drop out to the surroundings later, or the insulating coating 120 may be present at the interface of the joint portion of the wire 11 depending on the conditions during cold welding. For this reason, when joining the wire 11 with the insulating coating part 120 by cold welding, the concern can be eliminated by removing the insulating coating part 120 at the tip of the wire 11 in advance. Moreover, when the conductor 121 part from which the insulating coating part 120 is removed is gripped, it is possible to prevent the insulating coating part 120 from slipping. And the joining by the stable cold pressure welding can be implemented.

Next, the removal of the insulating coating 120 will be described. The insulating coating 120 is firmly attached to the conductor 121 of the wire 11. For this reason, the process of removing the insulating coating 120 is not easy. For example, it is possible to mechanically remove the insulating coating 120 with a cutter blade or an iron brush. However, if a part of the conductor 121 of the wire 11 is removed simultaneously, the outer diameter of the wire 11 will vary. For this reason, the holding state of the wire 11 at the time of cold pressure welding varies. However, it is possible to remove only the insulating coating 120 by removing the insulating coating 120 by heat energy using a laser or the like, or by removing the insulating coating 120 by a chemical reaction using chemicals.

Next, cold pressure welding using the die 1 in the fourth embodiment will be described. FIG. 14 shows the structure of a die according to Embodiment 4 of the present invention. FIG. 14 is a cross-sectional view showing a cross-section in the XX direction in FIG. 2, and shows a state of the die after insertion of the wire. In the figure, the same parts as those in the above embodiments are denoted by the same reference numerals, and description thereof is omitted. The die 1 is formed in the same manner as in the first embodiment, and each of the

wires

11a and 11b has a portion corresponding to the abutting portion 4 when inserted into the coil chuck portion 2, with the insulating coating portion 120 removed, and a conductor Only 121 is formed.

FIG. 15 is a cross-sectional view showing the cross-section in the XX direction in FIG. 2, showing the configuration of another die according to Embodiment 4 of the present invention, and shows the state of the die after insertion of the wire. In the figure, the same parts as those in the above embodiments are denoted by the same reference numerals, and description thereof is omitted. Similarly to the case shown in FIG. 14, each of the

wires

11 a and 11 b is formed of only the conductor 121, with the insulating coating 120 removed, and the portion corresponding to the abutting portion 4 when inserted into the coil chuck portion 2. ing. The inner wall portion 2 i of the coil chuck portion 2 is formed in the same size as the wire 11 in all cases. Therefore, in the portion where the wire rods come into contact with each other, the

wire rods

11a and 11b are formed of only the conductor 121, so that they touch the outer shape portions of the

wire rods

11a and 11b held by the coil chuck portions 2. It is formed larger than the size of the outer portion of each

wire

11a, 11b.

FIG. 16 shows another die configuration according to the fourth embodiment of the present invention. FIG. 16 is a cross-sectional view showing a cross-section in the XX direction in FIG. 2, and shows a state of the die after insertion of the wire. In the figure, the same parts as those in the above embodiments are denoted by the same reference numerals, and description thereof is omitted. Here, the insulating coating 120 is removed from all the portions corresponding to the portions inserted into the coil chuck portion 2 when inserted into the coil chuck portion 2, and the

wires

11a and 11b are formed only by the conductor 121. Yes. The inner wall portion 2j of the pair die 100, 101 of each coil chuck portion 2 of the die 1 where the wire rods come into contact with each other is formed larger than the size of the outer portion of the conductor 121 of each

wire rod

11a, 11b. Therefore, the outer portions of the

wires

11a and 11b gripped by the coil chuck portions 2 do not contact the conductor 121 from which the insulating coating portion 120 has been removed. Further, the inner wall portion 2k other than the portion where the wire rods of both the pair dies 100, 101 of the coil chuck portion 2 are in contact with each other corresponds to the outer portion of each

wire rod

11a, 11b, here the conductor 121 from which the insulating coating portion 120 is removed. It is formed so as to have a contact portion.

According to the die of the fourth embodiment configured as described above, the insulating film portion is not variably formed because the insulating film portion is removed and bonded, as well as the same effects as those of the above embodiments. It is possible to eliminate the possibility of intervening at the joint interface.

Embodiment 5 FIG.
In each of the above embodiments, the type of the wire is not particularly shown. For example, a case where the hard first wire 11a and the second wire 11b softer than the hardness of the first wire 11a are used will be described. In this way, when different kinds of metals are cold-welded, the manner in which the burrs 13 generated in the cold-welding process are different between the wire rods. Specifically, the burr 13 is generated in advance from the soft second wire 11b, and the generated burr 13 may suppress the generation of the burr 13 from the hard first wire 11a.

In order to solve this problem, the taper angle of the burr storage portion 5 provided in the die 1 is formed with a significant difference between the pair dies 100 and 102, and is handled. That is, the taper angle θ2 of the burr storage part 5 on the pair die 101 side where the soft second wire 11b is disposed is larger than the taper angle θ1 of the burr storage part 5 on the pair die 100 side where the hard first wire 11a is disposed. Form. Thereby, even when many burrs 13 are generated in the soft second wire 11b during joining, the burr 13 can be easily and stably discharged because the taper angle θ2 of the burr storage portion 5 is formed large. Therefore, it becomes possible to ensure the joining quality by the stable cold pressure welding.

According to the die of Embodiment 5 configured as described above, the same effects as those of the above embodiments can be obtained, and by adjusting the taper angle of the burr storage part, The bonding quality can be ensured even in the bonding.

It should be noted that the present invention can be freely combined with each other within the scope of the invention, and each embodiment can be appropriately modified or omitted.

Claims

Two pair dies constituting a coil chuck part that grips the wire rod with a pair of die pieces are provided, and the pair of dies are brought into contact with each other so that the wire rods gripped by the coil chuck portion are brought into contact with each other. In cold welding dies,
The coil chuck portion has a cooling portion in which a part or all of the inner diameter of the inner wall portion of the portion for contacting the wire rods is larger than the inner diameter of the inner diameter portion of the portion gripping the wire rod. Dies for pressure welding.
The cold pressure welding die according to claim 1, further comprising a burr storage portion formed around a portion of the coil chuck portion where the wires are in contact with each other.
The cold pressure welding die according to claim 2, wherein the burr storage portion is formed in a tapered shape that decreases in size toward the coil chuck portion side.
The cold pressure welding die according to claim 3, wherein the taper-shaped taper angle of the burr storage portion is formed in a different size for each pair die.
The inner wall part other than the part for the wire rods of the coil chuck part to contact each other,
The cold pressure welding die according to any one of claims 1 to 4, wherein the die is formed at a portion for holding the wire.
The inner wall part other than the part for the wire rods of the coil chuck part to contact each other,
A first portion of a portion not gripping the wire;
The cold pressure welding die according to any one of claims 1 to 4, wherein second portions of the portion that grips the wire are alternately formed.
Wires joined by cold welding are
The wire in which the cross-sectional area of the joint part of the said wire is formed larger than the cross-sectional area of the strand of the said wire.
The wire according to claim 7, wherein the joint portion of the wire has a larger cross-sectional area at a joint portion than at the other joint portion.