Method for manufacturing contact member for electric and electronic circuits and apparatus for manufacturing contact member for electric and electronic circuits

Abstract

To provide a method for accurately welding a metal wire at a predetermined position of a spring base material to manufacture a contact member.SOLUTION: A method for manufacturing a contact member for electric and electronic circuits includes: a spring base material supplying step; a metal wire supplying step; and a contact member forming step of superposing and clamping the supplied spring base material and metal wire between an upper rotating electrode and a lower rotating electrode, and continuously seam-welding them to produce the contact member for electric and electronic circuits. In the contact member forming step, the position of the spring base material relative to the rotating electrodes is controlled by pressing the spring base material against a reference surface of the rotating electrode, and the metal wire is guided into a V-shaped guide groove provided at an outer peripheral portion of the lower rotating electrode, positioned at a predetermined position of the spring base material, and seam-welded.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a method for manufacturing a contact member for an electric and electronic circuit, and an apparatus for manufacturing a contact member for an electric and electronic circuit, which are used for various contact parts constituting an electric and electronic circuit.

Background Art

[0002] Contact members used in electric and electronic circuits that constitute sliding contacts used in combination with printed resistors, etc., require mechanical properties such as spring properties and wear resistance in order to maintain electrical characteristics such as contact resistance and stability during sliding. For this reason, it is desirable to use a noble metal-based material with low contact resistance and excellent wear resistance. However, since noble metal materials are limited to the minimum necessary use in terms of cost, generally, noble metal-based materials are used only for the contact part, and noble metal-based materials are disposed on the "spring material" serving as the base material by welding, plating, or the like. This is the common practice.

[0003] The electric and electronic contacts configured in this way are processed into a shape suitable for the structure of the contact parts to be used. At this time, it is an essential requirement that the contact portion of the contact is appropriately arranged at a desired position, and it is necessary to weld the metal wire to the exact position of the base material (spring material) in order to influence the performance and reliability as a contact part.

[0004] Patent Document 1 (Japanese Patent Application Laid-Open No. 9-106874) describes a method for manufacturing a contact / connection member for an electric and electronic part and an apparatus for manufacturing the same, in which a noble metal wire for a contact / connection member is welded to a base material for a contact / connection member by resistance welding. In the method for manufacturing a contact / connection member for an electric and electronic part described in Patent Document 1, diffusion bonding is performed by applying current between two electrodes while pressing a wire between a mother rotating electrode (upper rotating electrode) and a variable rotating roller electrode (lower rotating electrode) against the upper or lower surface of the base material at the welding position, so that the wire is welded to a predetermined position on the upper or lower surface of the base material.

Prior Art Documents

Patent Documents

[0005] Patent Document 1 Japanese Patent Laid-Open No. 9-106874 Summary of the Invention Problems to be Solved by the Invention

[0006] However, in the method for manufacturing a contact or a connecting member for an electric or electronic component described in Patent Document 1 above, the metal wire is guided and positioned in a V-groove provided in a lower rotating electrode. On the other hand, for the base material (spring material), since there is no positioning mechanism, when this base material (spring base material) is sent to the rotating electrode, if it is deformed or swings left and right with respect to the feeding direction (front-rear direction) of the base material, the relative position between the metal wire and the V-groove of the lower rotating electrode may change. For this reason, there has been a case where the metal wire is not welded to the exact position of the base material (spring material). What is required is to provide a method and an apparatus for manufacturing a contact member for welding a metal wire to a base material (spring material) with a predetermined welding strength. Means for Solving the Problems

[0007] The method for manufacturing a contact member for an electric or electronic circuit according to the present invention is a method for manufacturing a contact member for an electric or electronic circuit in which a metal wire is superposed on a spring base material and welded, and includes a spring base material supply step for supplying the spring base material to a rotating electrode including an upper rotating electrode and a lower rotating electrode, a metal wire supply step for supplying the metal wire to the rotating electrode, and a contact member creation step for sandwiching the spring base material and the metal wire between the upper rotating electrode and the lower rotating electrode in a superposed state and continuously performing seam welding to produce a contact member for an electric or electronic circuit. Further, in the contact member creation step, by pressing the spring base material against a reference surface of the rotating electrode, the position of the spring base material with respect to the rotating electrode is controlled, and the metal wire is guided by a V-shaped guide groove provided on an outer peripheral portion of the lower rotating electrode and positioned at a predetermined position of the spring base material and seam welded.

[0008] In the method for manufacturing a contact member for an electric / electronic circuit according to the present invention, in the contact member creation step, by pressing a spring base material against the reference surface of a rotary electrode, the position of the spring base material with respect to the rotary electrode is controlled, and a metal wire is guided by a V-shaped guide groove provided on the outer peripheral portion of a lower rotary electrode and positioned at a predetermined position of the spring base material and seam welded. Thereby, the metal wire can be welded to a predetermined position of the spring base material accurately and with high precision. Further, a contact member for an electric / electronic circuit in which the metal wire is welded to a predetermined position of the spring base material accurately and with high precision can be manufactured with good reproducibility and stability.

[0009] Further, in the method for manufacturing a contact member for an electric / electronic circuit according to the present invention, in a state where the spring base material and the metal wire are sandwiched between the upper rotary electrode and the lower rotary electrode, the separation distance between the top of the lower rotary electrode and the surface of the spring base material is controlled within a predetermined range, and the metal wire and the spring base material are seam welded.

[0010] In the method for manufacturing a contact member for an electric / electronic circuit according to the present invention, since the metal wire and the spring base material are seam welded in a state where the separation distance between the top of the lower rotary electrode and the surface of the spring base material is controlled within a predetermined range, the metal wire and the spring base material can be surely and reproducibly seam welded while maintaining the circular shape of the top of the metal wire. Further, thereby, a contact member for an electric / electronic circuit excellent in electrical characteristics such as contact resistance and stability during sliding can be provided.

[0011] Further, in the method for manufacturing a contact member for an electric / electronic circuit according to the present invention, it may be characterized in that the separation distance between the top of the lower rotary electrode and the surface of the spring base material is set by the angle and depth of the V-shaped guide groove provided on the outer peripheral portion of the lower rotary electrode.

[0012] Further, in the method for manufacturing a contact member for an electric / electronic circuit according to the present invention, it may be characterized in that the separation distance between the top of the lower rotary electrode and the surface of the spring base material is in the range of 30 μm or more and 50 μm or less.

[0013] In addition, in the method for manufacturing a contact member for an electric and electronic circuit according to the present invention, after the step of creating the contact member, an inspection step for inspecting the contact member for the electric and electronic circuit can be further included. Further, the inspection step may be characterized in that the amount of the elution part where the outer edge of the welded part where the spring base material and the metal wire are seam-welded appears on the surface is measured, and the quality is determined based on the measured amount of the elution part. Thereby, it is possible to determine the quality of the welding state by measuring the amount of the elution part of the welded part without performing a destructive test of cutting the seam-welded part and checking its cross section.

[0014] In addition, in the method for manufacturing a contact member for an electric and electronic circuit according to the present invention, elution part data indicating the relationship between the amount of the elution part and the generation state of the joint part formed in the welded part may be acquired in advance, and based on the elution part data, the quality may be determined based on the amount of the elution part.

[0015] In addition, the manufacturing apparatus for a contact member for an electric and electronic circuit according to the present invention is a manufacturing apparatus for a contact member for an electric and electronic circuit that overlaps and welds a metal wire on a spring base material, and includes a spring base material supply means, a metal wire supply means, an upper rotating electrode, and a lower rotating electrode. The spring base material supplied from the spring base material supply means and the metal wire supplied from the metal wire supply means are clamped between the upper rotating electrode and the lower rotating electrode in a superposed state and continuously seam-welded. It also includes a butting unit for controlling the position of the spring base material with respect to the rotating electrode by pressing the spring base material against the reference surface of the rotating electrode. The lower rotating electrode has a V-shaped guide groove provided on the outer peripheral portion, and the positioning unit guides the metal wire to a predetermined position of the spring base material guided by the guide groove provided on the lower rotating electrode while maintaining the state where the position of the spring base material with respect to the rotating electrode is controlled, and is configured to be seam-welded. By seam-welding the metal wire and the spring base material using the manufacturing apparatus for a contact member for an electric and electronic circuit, the metal wire can be accurately welded to a predetermined position of the spring base material with high precision.

[0016] In addition, in the manufacturing apparatus for the contact member for an electric and electronic circuit according to the present invention, when seam-welding the metal wire to the spring base material, a positioning unit can be further provided to control the amount of deflection of the spring base material. The positioning unit has a first pressing member and a second pressing member that are separated by a predetermined distance and arranged opposite to each other, and the spring base material passes through a gap formed between the first pressing member and the second pressing member, so that the amount of deflection of the spring base material is restricted. This may be characterized.

Effect of the Invention

[0017] In the manufacturing method of the contact member for an electric and electronic circuit according to the present invention, there is a contact member creating step of sandwiching a spring base material and a metal wire in a superposed state between an upper rotating electrode and a lower rotating electrode and continuously performing seam welding to produce a contact member for an electric and electronic circuit. By pressing the spring base material against the reference surface of the rotating electrode, the position of the spring base material with respect to the rotating electrode is controlled, and the metal wire is guided by a V-shaped guide groove provided on the outer peripheral portion of the lower rotating electrode and positioned at a predetermined position of the spring base material for seam welding. Thereby, the metal wire can be accurately welded to a predetermined position of the spring base material with high precision. In addition, a contact member for an electric and electronic circuit in which the metal wire is accurately welded to a predetermined position of the spring base material with high precision can be manufactured with good reproducibility and stability.

Brief Description of the Drawings

[0018]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

Embodiments for Carrying Out the Invention

[0019] A manufacturing apparatus for a contact member used in an electric and electronic circuit according to some embodiments, and a method for manufacturing a contact member used in an electric and electronic circuit will be described below with reference to the drawings. In the following description, the same elements in the drawings are denoted by the same reference numerals, and redundant descriptions are omitted. In the description, terms indicating directions such as "upper", "lower", "right", and "left" are for convenience based on the state shown in the drawings.

[0020] The manufacturing apparatus for a contact member according to the present embodiment is an apparatus for manufacturing a contact member used in an electric and electronic circuit. More specifically, it is an apparatus for seam-welding a metal wire used for the contact portion of the contact member to a "spring base material" serving as a base material. As the material of the metal wire, for example, an alloy mainly made of a noble metal-based material such as palladium or silver can be used. Also, as the material of the spring base material, for example, an alloy of copper and nickel can be used.

[0021] FIG. 1 schematically shows a contact member manufacturing apparatus 1 for manufacturing a contact member used in an electric and electronic circuit according to the present embodiment. Also, FIG. 2 shows an enlarged view of the rotating electrode portion in the contact member manufacturing apparatus.

[0022] Referring to FIG. 1, the contact member manufacturing apparatus 1 is, for example, an apparatus for manufacturing a contact member for an electric and electronic circuit formed by overlapping and seam-welding a metal wire on a strip-shaped spring base material. As shown in FIG. 1, the contact member manufacturing apparatus 1 can include a spring base material supply means 2, a metal wire supply means 3, a rotating electrode 4 having an upper rotating electrode and a lower rotating electrode, and a winding means 5 (winding device) for the assembled product.

[0023] Referring to FIG. 1, the outline of the contact member manufacturing apparatus 1 will be described. In the contact member manufacturing apparatus 1, the spring base material is wound around and stored in the spring base material reel 6, and is passed between the first detection sensor 8 and the second detection sensor 9 arranged in the spring base material supply means 2. When the operation of the contact member manufacturing apparatus 1 starts, the reel drive motor that rotates the spring base material reel 6 rotates, and the spring base material 7 is sent out to the rotary electrode 4. At the same time, the metal wire 11 wound around the metal wire reel 10 is also sent out to the rotary electrode 4. Thereafter, the spring base material 7 and the metal wire 11 are sandwiched between the upper and lower rotary electrodes and seam welded to form a contact member. The rotary electrode 4 has an upper rotary electrode 14 and a lower rotary electrode 15 as shown in FIG. 2. The contact member 40 welded by the rotary electrode 4 is sent out as a welded finished product toward the outlet side of the contact member manufacturing apparatus, that is, the winding means 5.

[0024] The spring base material 7 wound around and stored in the spring base material reel 6 may be wound in a state with a curl on the spring base material reel 6 or in a state of being tightly wound. When the spring base material 7 is sent out to the rotary electrode 4 in this state, an irregular load is applied to the reel drive motor (not shown) that rotates the spring base material reel 6, and the rotational speed may change irregularly. At this time, since the supply speed of the spring base material 7 changes, slack may occur in the spring base material 7 supplied from the spring base material reel 6.

[0025] In this embodiment, a spring base material supply device 2 for supplying the spring base material 7 to the rotary electrode 4 is provided. As shown in FIG. 1, the spring base material supply device 2 can include a reel 6 for the spring base material, a slack detection sensor for detecting the amount of slack of the spring base material 7 supplied from the reel 6 for the spring base material, and a reel drive motor control device that detects a signal from the slack detection sensor and controls the rotational force of the reel drive motor. In this embodiment, the slack detection sensor is composed of a first detection sensor 8 and a second detection sensor 9 arranged opposite to the first detection sensor 8. When the spring base material 7 is sent out to the rotary electrode 4 while passing between the first detection sensor 8 and the second detection sensor 9, the distance between the first detection sensor 8 and the spring base material 7 and the distance between the second detection sensor 9 and the spring base material 7 are detected. When the spring base material 7 has a slack of a predetermined amount or more, it is detected that the distances between the first detection sensor 8 and the spring base material 7 and between the second detection sensor 9 and the spring base material 7 have changed, and the reel drive motor is controlled so that the distances between the first detection sensor 8 and the spring base material 7 and between the second detection sensor 9 and the spring base material 7 become predetermined values. Thereby, the spring base material 7 can be supplied to the rotary electrode 4 while having a predetermined amount of slack.

[0026] When slack occurs in the spring base material 7, in this apparatus, the force for gripping the spring base material 7 with the upper and lower rotary electrodes during welding is related to the condition (weight) that determines weldability. Therefore, there is a limit to the force for gripping the spring base material 7 with the rotary electrode. If there is slack in the spring base material 7, in a relatively weakly gripped state, due to the self-weight of the spring base material 7, a stress for the spring base material 7 to move backward occurs, resulting in a deviation in the seam welding position with the metal wire 11 described later and causing defects. By introducing the spring base material supply means 2, smooth supply of the spring base material 7 can be achieved, and the spring base material 7 can be supplied to the rotary electrode 4 while maintaining a predetermined amount of slack.

[0027] Referring to FIG. 1, the metal wire 11 is wound around and stored in the metal wire reel 10. When the operation of the contact member manufacturing apparatus 1 starts, the metal wire 11 is sent to the rotary electrode 4 together with the spring base material 7, and seam welding is performed while being sandwiched between the upper and lower rotary electrodes 14 and 15. As shown in FIGS. 1 and 2, in the present embodiment, the metal wire 11 wound around the metal wire reel 10 is configured to be sent to the rotary electrode 4 after passing through the metal wire roller 16 and the metal wire guide 17. The metal wire guide 17 is disposed between the metal wire roller 16 and the upper and lower rotary electrodes 14 and 15.

[0028] The metal wire guide 17 can have a guide portion for hooking and guiding the metal wire 11. By adjusting the height and angle, the metal wire guide 17 can send the metal wire to the rotary electrode at a predetermined angle. Further, a metal wire detection sensor (not shown) for detecting the presence or absence of the metal wire 11 is attached to the metal wire guide 17. The metal wire detection sensor is attached to detect that the metal wire 11 sent from the metal wire reel 10 to the rotary electrode 4 has disappeared. For example, when the metal wire detection sensor detects that the metal wire sent to the rotary electrode 4 has disappeared, an alarm can be sounded or the operation of the contact member manufacturing apparatus 1 can be stopped.

[0029] Referring to FIG. 3, a positioning unit 18 and a butting unit 19 are attached in the vicinity of the upper and lower rotary electrodes 14 and 15. In the contact member used for an electric / electronic circuit, the metal wire 11 to be welded to the spring base material 7 needs to be welded accurately at a predetermined position of the spring base material 7 with high precision. In order to weld the metal wire 11 at the predetermined position of the spring base material 7, the positioning unit 18 and the butting unit 19 for controlling the amount of deflection of the spring base material 7 during seam welding are provided in the vicinity of the upper and lower rotary electrodes 14 and 15.

[0030] FIG. 3 shows a diagram for explaining the positioning unit 18 and the butting unit 19. The positioning unit 18, the butting unit 19, and the upper and lower rotary electrodes 14 and 15 are attached to the rotary electrode holding table, and their relative positions are fixed.

[0031] Further, FIG. 4 shows a cross-sectional view taken along line IV-IV of FIG. 3. Referring to FIG. 3, the positioning unit 18 vertically arranges a plate-like first pressing member 20 having a substantially U-shaped configuration and a second pressing member 21 disposed opposite to the first pressing member, with a gap provided therebetween. The gap between the first pressing member 20 and the second pressing member 21 is configured such that the spring base material 7 passes therethrough. The end portions of the first pressing member 20 and the second pressing member 21 on the side opposite to the surface facing the abutting unit 19 are supported by a support member. Further, a bearing 24 that is inserted through the support member and rotatably supported is provided between the first pressing member 20 and the second pressing member 21. When the spring base material 7 and the wire 11 are moving forward while being seam-welded, the spring base material 7 can move smoothly while being pressed against the bearing 24.

[0032] Also, the second pressing member 21 disposed with the first pressing member 20 of the positioning unit may each include a front arm portion 22 and a rear arm portion 23. Between the front arm portion 22 and the rear arm portion 23, vertical rotation electrodes 14 and 15 are disposed. The distance between the front arm portion 22 and the rear arm portion 23 is set to such an extent that the rotation electrodes do not contact each other and the influence of the deflection of the spring base material 7 during seam welding can be reduced. In this embodiment, it is set to a size of about 35 mm.

[0033] Also, the size of the gap between the first pressing member 20 and the second pressing member 21 of the positioning unit 18 can be determined by a range that limits the amount of deflection of the spring base material 7. The amount of deflection of the spring base material 7 is preferably limited to 0.125 mm or less. When performing seam welding with the vertical rotation electrodes 14 and 15, if the spring base material 7 has a deflection greater than a predetermined amount, variations may occur in the position of the wire 11 welded to the spring base material 7. In order to reduce such variations in the welding position of the wire 11 to the spring base material 7, the amount of deflection of the spring base material 7 can be limited by the size of the gap between the first pressing member 20 and the second pressing member 21 of the positioning unit 18. In this embodiment, the gap between the first pressing member and the second pressing member is set to about 0.125 mm.

[0034] Also, as described above, in order to control the position of the spring base material 7 for welding the metal wire 11, in addition to providing a positioning unit 18 to control the amount of deflection of the spring base material 7 during seam welding, a abutting unit 19 is provided to control the position of the spring base material 7 in the left - right direction (X - direction) with respect to the rotating electrode. Variations also occur in the position of the metal wire 11 welded to the spring base material 7 due to the positional deviation of the spring base material 7 in the left - right direction with respect to the upper and lower rotating electrodes. When this left - right positional deviation occurs, it may not satisfy the specifications as an electrode of the contact member (see FIG. 10) used in the electric and electronic circuits. The allowable range of the left - right deviation of the metal wire 11 is, for example, about 0.01 to 0.03 mm in the left - right direction.

[0035] Referring to FIGS. 3 and 4, the abutting unit 19 can have an abutting roller 25 for abutting the spring base material 7 against the bearing 24 of the positioning unit 18. In this embodiment, this bearing 24 forms a reference plane with respect to the upper and lower rotating electrodes 14 and 15. The abutting roller 25 is pressed against the spring base material 7 by an elastic member 26 with a predetermined biasing force. The abutting unit 19 can control the position of the spring base material 7 with high precision with respect to the upper and lower rotating electrodes (or the V - shaped guide groove 27 provided for guiding the metal wire on the rotating electrode 4). In this embodiment, the seam welding position of the spring base material 7 and the metal wire 11 can be controlled with an accuracy of 0.02 mm.

[0036] In this embodiment, the abutting unit 19 abuts against the spring base material 7 to highly accurately control the position of the spring base material with respect to the rotating electrode. At this time, when the spring base material 7 is pushed in the left-right direction, it may bulge upward or downward and deform in the left-right direction. Even due to this deformation of the spring base material 7, variations may occur in the position of the metal wire 11 welded to the spring base material 7. The amount of deformation due to the upward and downward bulging of the spring base material 7 is restricted by the gap portion of the positioning unit 18. Therefore, even if the spring base material 7 is pushed and deformed in the left-right direction by the abutting unit 19, the variation in the position of the metal wire 11 welded to the spring base material 7 can be reduced by cooperating with the positioning unit 18.

[0037] The contact member used in the electric and electronic circuit has a structure in which the metal wire 11 is arranged only at the portion that abuts against the opposing contact body, and a fine design is required so that the position of the metal wire 11 does not shift or the top of the metal wire 11 is not crushed. In this embodiment, a perspective view of the contact member in which the metal wire 11 is seam-welded to the spring base material 7 is shown in FIG. 11. This contact member is punched by press working to form a contact for an electronic component as shown in FIG. 12. If the position of the metal wire 11 seam-welded to the spring base material 7 shifts, the position of part B of the contact for the electronic component shown in FIG. 12 will shift, and the quality as a contact for the electronic component cannot be satisfied. For this reason, it is necessary to regulate the left-right displacement of the metal wire 11 by the cooperation of the positioning unit 18 and the abutting unit 19.

[0038] Next, the rotating electrode for performing seam welding will be described in detail. FIG. 5 schematically shows an enlarged side view of the rotating electrode viewed from the front side.

[0039] Referring to FIG. 5, the rotating electrodes can be composed of an upper rotating electrode 14 and a lower rotating electrode 15 which are arranged opposite to each other. As shown in FIG. 5, the lower rotating electrode 15 has a V-shaped guide groove 23 provided along its outer periphery. The metal wire 11 is supplied from the inlet side of the rotating electrode, held in the V-shaped guide groove 23 of the lower rotating electrode 15, and pressed against the surface of the spring base material 7 held between the upper rotating electrode 14 and the lower rotating electrode 15. A welding current is applied to the rotating electrodes, and the metal wire 11 can be seam-welded to a predetermined position on the surface of the spring base material 7. By performing this seam welding while the rotating electrodes are rotating, the metal wire 11 can be continuously welded to the surface of the spring base material 7.

[0040] Referring again to FIGS. 1 and 2, an upper power supply shaft (not shown) is connected and fixed to the upper rotating electrode 14, and the upper power supply shaft is supported by an upper housing (not shown) and supports the upper rotating electrode 14 rotatably. Similarly, a lower power supply shaft (not shown) is supported by a lower housing (not shown) and supports the lower rotating electrode 15 rotatably. A water passage hole (not shown) for passing chilled cooling water is axially formed in the lower power supply shaft.

[0041] In this embodiment, a circulation cooling means for supplying cooling water to suppress the temperature rise of the rotating electrodes during welding is provided by passing cooling water through the water passage holes provided in the upper power supply shaft and the lower power supply shaft, and the upper rotating electrode 14 and the lower rotating electrode 15 are configured to be cooled.

[0042] Next, a method for manufacturing a contact member used in an electric and electronic circuit using the contact member manufacturing apparatus 1 will be described in detail. FIG. 5 shows a flowchart for explaining the method for manufacturing a contact member used in an electric and electronic circuit. Referring to FIG. 5, the method for manufacturing a contact member can include a spring base material supply step S01, a metal wire supply step S02, a seam welding step S03, an inspection step S04, and a winding step S05. These steps will be described below.

[0043] (Spring Base Material Supply Step S01) First, the spring base material supply process S01 will be described. In the spring base material supply process S01, the spring base material 7 is supplied from the spring base material supply device 2 to the rotary electrode 4. The spring base material 7 is wound around and stored on the spring base material reel 6, and can pass between the sag detection sensors 8 and 9 and be supplied to the rotary electrode. The sag detection sensor is composed of a first detection sensor 8 and a second detection sensor 9 arranged opposite to the first detection sensor 8.

[0044] The spring base material 7 wound around and stored on the spring base material reel 6 may be wound with a curl on the spring base material reel 6 or wound in a state of being tightly wound. When the spring base material 7 is sent out to the rotary electrode in this state, an irregular load is applied to the reel drive motor that rotates the spring base material reel 6, and the rotation speed may change irregularly.

[0045] When the rotation speed of the reel drive motor changes irregularly, sag may occur in the stretching direction (Y direction in FIG. 3) of the spring base material 7 supplied from the spring base material supply means 2. When sag occurs in the spring base material 7, the spring base material 7 is pulled back to the spring base material supply device 2 side by its weight. At this time, when sag occurs in the spring base material 7 in the stretching direction, it may also swing in the left-right direction (X direction) at the same time. As a result, variations occur in the position of the spring base material 7 in the left-right direction (X direction) with respect to the rotary electrode, and when the metal wire 11 is seam welded to the spring base material 7, the position of the metal wire 11 may shift.

[0046] In this embodiment, when the spring base material 7 has a sag of a predetermined amount or more, the reel drive motor control device determines that the distance between the first detection sensor 8 and the spring base material 7 and the distance between the second detection sensor 9 and the spring base material 7 have changed, and controls the rotation of the reel drive motor so that the distance between the first detection sensor and the spring base material 7 and the distance between the second detection sensor and the spring base material 7 become predetermined values, thereby controlling the supply amount of the spring base material 7. As a result, the spring base material 7 can be supplied to the rotary electrode while having a predetermined amount of sag.

[0047] (Wire supply process S02) Also, in the wire supply process S02, the wire 11 is supplied to the rotary electrode together with the spring base material 7. The wire 11 is wound around and stored in a wire reel 10. When the operation of the contact member manufacturing apparatus 1 starts, the wire 11 is sent to the rotary electrode together with the spring base material 7, and seam welding is performed while being sandwiched together with the spring base material 7. In the present embodiment, the wire 11 wound around the wire reel 10 is configured to be sent to the rotary electrode after passing through a wire roller 16 and a wire guide 17. By providing the wire guide 17 between the wire roller 16 and the rotary electrode, the height and angle of the wire 11 sent to the rotary electrode can be adjusted. As a result, the wire 11 can be sent out to the rotary electrode at a predetermined angle.

[0048] Also, a wire detection sensor (not shown) is attached to the wire guide 17, and the remaining amount of the wire is detected by this wire detection sensor. When the wire detection sensor detects that the wire has run out, the operation of the contact member manufacturing apparatus 1 can be stopped. Note that the wire 11 is supplied to the rotary electrode together with the spring base material 7 when the rotary electrode rotates during seam welding.

[0049] (Seam welding process S03) Next, the seam welding process S03 will be described in detail. The spring base material 7 sent to the rotary electrode by the spring base material supply device 2 and the wire 11 sent to the rotary electrode by the wire supply means 3 are seam welded in the seam welding process S03. The seam welding process S03 can include a positioning process S03a and a welding process S03b.

[0050] (a) Positioning process S03a First, the spring base material 7 sent to the rotating electrode is positioned by the abutting unit 19 and the positioning unit 18 so as to be arranged at a predetermined position with respect to the position of the rotating electrode 4. First, the spring base material 7 is pressed in the width direction (X direction) of the spring base material 7 by the abutting roller 25 of the abutting unit 19 and abutted against the bearing 24 of the positioning unit 18. The abutting unit 19 can accurately control the position of the spring base material 7 with respect to the rotating electrode (or the V-shaped guide groove 27 for guiding the metal wire provided on the rotating electrode). At this time, since the spring base material 7 is pressed in the width direction (X direction) by the abutting roller 25 of the abutting unit 19, the central portion of the spring base material 7 may be deformed so as to bulge upward (hereinafter, this deformation of the spring base material is referred to as "bending").

[0051] When the central portion of the spring base material 7 is deformed so as to bulge upward, the relative position between the V-shaped guide groove 27 for guiding the metal wire formed in the lower rotating electrode 15 and the spring base material 7 changes. Therefore, the position where the metal wire 11 held in the V-shaped guide groove 27 of the lower rotating electrode 15 is welded to the spring base material 7 will be deviated by the amount of the deformed peak-like slope of the spring base material 7.

[0052] In the present embodiment, in the positioning unit 18, the spring base material 7 is passed through the gap between the first pressing member 20 and the second pressing member 21 arranged vertically opposite to each other, and the amount of bending of the spring base material 7 can be limited to a predetermined range. In the present embodiment, the amount of bending of the spring base material 7 is limited to about 0.125 mm or less depending on the size of the gap between the first pressing member 20 and the second pressing member 21.

[0053] Further, in the present embodiment, by positioning with the abutting unit 19 and the positioning unit 18, the seam welding position of the spring base material 7 and the metal wire 11 can be controlled with an accuracy of about 0.01 to 0.03 mm in the left-right direction. Even if the spring base material 7 is deformed by being pushed in the left-right direction by the abutting unit 19, the variation in the position of the metal wire 11 welded to the spring base material 7 can be reduced by cooperating with the positioning unit 18.

[0054] (b) Welding process S03b This process is a process of seam - welding the metal wire 11 to the spring base material 7 with the spring base material 7 and the metal wire 11 sandwiched between the upper rotating electrode 14 and the lower rotating electrode 15. In this embodiment, the welding current during seam - welding is supplied using an inverter power source to perform seam - welding. FIG. 7 schematically shows the welding current waveform supplied by the inverter power source.

[0055] As welding conditions, first, when seam - welding the metal wire 11 and the spring base material 7 with the metal wire 11 held in the V - shaped guide groove 27 of the lower rotating electrode 15, seam - welding is performed while applying a certain load to the metal wire 11 and the spring base material 7. In this embodiment, by applying a load of 1000 g to the upper rotating electrode, this load is applied to the metal wire 11 and the spring base material 7.

[0056] The spring base material 7 is sent toward the winding means 5 side by rotationally driving the lower rotating electrode 15. The feeding speed of the spring base material 7 can be, for example, about 5 mm / sec. (5 millimeters per second). While seam - welding the metal wire 11 to the spring base material 7, the contact member is sent toward the winding device 5 side.

[0057] The current supplied from the inverter power source is a pulse current as shown in FIG. 7, and the peak value of the pulse current can be about 1 mA (1 milliampere). Also, the energized time (ON time) is set to about 5 msec. (5 milliseconds), the non - energized time (OFF time) is set to about 25 msec. (25 milliseconds), and one cycle of the pulse is set to about 30 msec. (30 milliseconds). Therefore, the metal wire 11 and the spring base material 7 are energized at an interval of 0.15 mm, and while diffusion - bonding, the metal wire 11 and the spring base material 7 are continuously seam - welded and sent toward the winding device 5 side.

[0058] Next, the state in which the metal wire 11 is seam-welded to the spring base material 7 in the welding step S03b will be described in detail. FIG. 8 shows a state diagram for explaining the state in which the metal wire 11 and the spring base material 7 are sandwiched between upper and lower rotating electrodes and seam-welded. Note that FIG. 8(a) is a diagram for explaining the state before seam-welding, and FIG. 8(b) is a diagram for explaining the state after seam-welding. As shown in FIG. 8(a), in the state before seam-welding, the spring base material 7 and the metal wire 11 are arranged between the upper rotating electrode 14 and the lower rotating electrode 15 in a state of being in contact with each other. The metal wire 11 is supported by a V-shaped guide groove 27 provided in the lower rotating electrode 15 and is in contact with the surface of the spring base material 7 supported by the upper rotating electrode 14. As described above, in order to improve the weldability, a predetermined load (a load of 1000 g in this embodiment) is applied to the metal wire 11 and the spring base material 7.

[0059] During seam-welding, while the welding current is flowing, the region where the metal wire 11 and the spring base material 7 are in contact and the vicinity thereof are heated and both are in a softened state. Referring to FIGS. 8(a) and 8(b), a predetermined load is applied to the upper rotating electrode. Due to the softening of the contact region between the metal wire 11 and the spring base material 7 and the vicinity thereof, the upper rotating electrode 14 can move downward to the line of the lower limit position 34 of the upper electrode during welding. As a result, the metal wire 11 and the spring base material 7 are pressure-welded by the downwardly moved upper rotating electrode 14 and seam-welded by diffusion bonding.

[0060] Specifically, as shown in FIGS. 8(a) and 8(b), first, a pure fusion diffusion joint (exudation part) 32 is formed at the interface contact part of different materials between the metal wire 11 and the spring base material 7. Then, under the influence of Joule heat, a strong joint (nugget) 33 in which fusion diffusion and solid-phase diffusion are mixed is formed, and the spring base material 7 and the metal wire 11 are surely joined. If the conditions of electric resistance welding are matched according to the materials of the spring base material 7 and the metal wire 11, since the spring base material 7 and the metal wire 11 travel at a constant speed due to the rotation of the rotating electrode, the metal wire 11 is continuously welded in the traveling direction on the spring base material 7. In this case, by cooling the upper and lower rotating electrodes by forced air cooling, circulating water cooling, etc., continuous welding for a long time becomes possible. FIG. 9 shows an electron microscope (SEM) photograph of the cross section of the seam weld. Referring to FIG. 9, the fusion diffusion joint (exudation part) 32 and the joint (nugget) 33 formed by seam welding can be confirmed.

[0061] According to the inventor's findings, in FIG. 8(a), it was found that the welding state varies depending on the distance between the top 35 of the lower rotating electrode set before seam welding and the surface of the spring base material 7. In FIG. 8(a), the results of experiments on the distance A (hereinafter referred to as the separation distance A) between the top 35 of the lower rotating electrode and the surface of the spring base material 7 and the welding state will be described. FIG. 10 schematically shows the welding state of the seam weld when the separation distance A is changed. In FIG. 10, FIGS. 10(a), 10(b), and 10(c) schematically show cross-sectional views of the welding state when the separation distance A is 30 μm, 50 μm, and 40 μm, respectively. Also, in this embodiment, a metal wire with a thickness of 90 μmφ (constant) in diameter is used for the thickness of the metal wire 11, and the angle of the V-shaped guide groove 27 of the lower rotating electrode is about 90 degrees.

[0062] In this embodiment, the separation distance A can be adjusted by setting the depth of the V-shaped guide groove 27 provided in the lower rotating electrode within a predetermined range. When the separation distance A is 30 μm, the depth of the V-shaped guide groove 27 is 80 μm (Fig. 10(a)). When the separation distance is 50 μm, the depth of the V-shaped guide groove 27 is 60 μm (Fig. 10(b)). Also, when the separation distance is 40 μm, the depth of the V-shaped guide groove 27 is 70 μm (Fig. 10(c)).

[0063] Referring to Fig. 10(a), it was found that no nugget was generated inside the welded portion and there were non-welded areas. In this case, since the welding strength is insufficient, problems such as the metal wire 11 peeling off from the spring base material 7 occur. When the separation distance A is set to a relatively small value of 30 μm, a lower rotating electrode with a V-shaped guide groove 27 having a relatively large depth of 80 μm is used. In this case, there is an advantage that the metal wire 11 can be stably held in the V-shaped guide groove 27 and the metal wire 11 can be prevented from falling out of the V-shaped guide groove 27. However, by setting the separation distance A to 30 μm, electrical contact may occur between the lower rotating electrode 15 and the spring base material 7. As a result, it was found by experiments that the welding current causes shunt (leakage) and does not reach the appropriate melting temperature.

[0064] Next, referring to FIG. 10(b), it was found that the circular shape 36 at the top of the metal wire was deformed and became a crushed shape. It was found that this was due to reducing the depth of the V-shaped guide groove 23. In FIG. 10(b), when the separation distance A is set to a relatively large value of 50 μm, a lower rotating electrode having a V-shaped guide groove 27 with a depth of 60 μm, which is a relatively small value, is used. When the depth of the V-shaped guide groove 27 is reduced, the stability of the metal wire 11 held in the V-shaped guide groove 27 decreases, but since the separation distance A can be ensured to be sufficiently large, the shunting of the welding current between the lower rotating electrode 15 and the spring base material 7 can be reduced. By the way, during seam welding, while the welding current is flowing, a molten temperature region is generated in the metal wire 11, and this molten temperature region flows into the V-shaped guide groove 27, but the slope of the V-shaped guide groove 27 acts as a barrier to prevent it from flowing out of the V-shaped guide groove 27. However, as shown in FIG. 10(b), when the depth of the V-shaped guide groove 27 is reduced, the length of the slope of the V-shaped guide groove 27 becomes smaller, and the function of the slope of the V-shaped guide groove 27 as a barrier decreases. As a result, during seam welding, the molten temperature region of the metal wire 11 flows out to the outside, and as a result, it was found that the circular shape 36 of the metal wire was deformed and the top shape became a crushed shape. In the present embodiment, when the depth of the V-shaped guide groove 27 is 60 μm or more, it was found that the circular shape 36 at the top of the metal wire was deformed and became a crushed shape.

[0065] FIG. 10(c) shows the welding state when seam welding is performed with an appropriate separation distance A set. The separation distance A at this time is 40 μm. Also, the depth of the V-shaped guide groove 27 of the lower rotating electrode is 70 μm. As shown in FIG. 10(c), a melted portion of the seam welding has occurred, and the spring base material 7 and the metal wire 11 are surely joined. Furthermore, the circular shape 36 at the top of the metal wire 11 also maintains its roundness, and the welding quality was qualified.

[0066] From the above results, it was found that good welding is possible by setting the depth of the V-shaped guide groove 27 provided in the lower rotating electrode to about 60 to 80 μm and the separation distance A to 30 to 50 μm and then performing welding. FIG. 12 is a perspective view of a contact member 40 formed by seam-welding a metal wire 11 to a spring base material 7 in a welding process. As will be described in detail later, this contact member 40 is punched by pressing to complete a contact for an electronic component used in an electric and electronic circuit (see FIG. 13). The portion B (tip portion) shown in FIG. 13 becomes the energizing portion of the contact for the electronic component, and it is essential for the contact for the electronic component that a metal wire with a rounded tip portion is arranged at the tip of this portion B. When the circular shape 36 at the top of the metal wire 11 is crushed as shown in FIG. 10(b), there may occur problems such as poor contact and increased contact resistance when the contact for the electronic component contacts the counterpart contact electrode. Also, damage to the counterpart contact electrode may occur. By performing seam welding under conditions that can obtain the state after welding as shown in FIG. 10(c), the contact for the electronic component can be manufactured while the circular shape at the top of the metal wire 11 is maintained.

[0067] (Inspection process S04) Next, an inspection process S04 is performed after the seam welding process. The inspection process S04 will be described in detail below. As described above, it was found that the distance between the top 35 of the lower rotating electrode and the surface of the spring base material 7, that is, the magnitude of the separation distance A, affects the change in the welding state and determines the quality. In the next inspection process S04, inspection is performed after seam-welding the metal wire 11 and the spring base material 7. In this inspection process S04, the surface of the seam-welded portion is photographed from above with a camera and image processing is performed, so that it is possible to determine the quality of the seam welding.

[0068] Fig. 11 shows a schematic diagram of the seam weld fusion zone. Fig. 11 shows the fusion zone 32 of the seam weld. This fusion zone 32 is the outer edge of the seam welded area. It has been found that by measuring the amount of the fusion zone 32 of the seam weld, the seam welding state can be qualitatively and quantitatively determined. According to the inventor's findings, the size of the fusion zone 32 is related to the formation state of the joint (nugget) 33 formed in the seam welding area. It has been found that it is possible to determine the quality of the joint by observing the fusion zone 32 without cutting the seam weld and observing the joint.

[0069] Specifically, the quality of the joint can be determined by the following procedure. It has been found that a fusion zone 32 of a predetermined size or more is required to form a good joint. First, cross-sections of the contact members 40 with different sizes of the fusion zone 32 are observed in advance, and fusion zone data showing the relationship between the size of the fusion zone 32 and the formation state of the joint (nugget) 33 are obtained by experiments. Next, the size of the fusion zone 32 of the seam weld is measured. The measured size of the fusion zone 32 is compared with the previously obtained fusion zone data. When the size (measured value) of the fusion zone 32 is equal to or greater than a predetermined size (standard value of the fusion zone 32), it is determined that the welding is good, and the seam welding is continued. On the other hand, when the size (measured value) of the fusion zone 32 is smaller than a predetermined size (standard value of the fusion zone 32), the welding process can be set to stop.

[0070] (Winding process S05) After the inspection process S04, the contact member 40 in a state where the metal wire 11 is continuously welded to a predetermined position of the spring base material 7 is wound around the finished product reel 37. This becomes an intermediate product of the contact member used in the electric and electronic circuits. After that, it is punched by press working, and the contact member for electric and electronic circuits shown in Fig. 13 is completed.

[0071] In this embodiment, the angle of the V-shaped guide groove 27 of the lower rotating electrode is set to about 90 degrees, but it may be set in the range of about 80 degrees to 100 degrees. Also, in this embodiment, the amount of deflection of the spring base material 7 is limited to 0.125 mm or less, but it is not limited to that range and may be defined in the range of about 0.1 to 0.2 mm. Further, in this embodiment, the allowable range of the lateral displacement of the metal wire 11 is implemented to be about 0.01 to 0.03 mm on both sides, but it is not limited to that range, and for example, an allowable range of about 0.01 to 0.05 mm is also possible.

[0072] Although the principles of the present invention have been illustrated and described in a preferred embodiment, it will be recognized by those skilled in the art that the present invention can be modified in arrangement and detail without departing from such principles. The present invention is not limited to the specific configurations disclosed in this embodiment. Accordingly, all modifications and changes coming from the scope of the claims and the spirit thereof are claimed.

Explanation of Reference Numerals

[0073] 1 Contact part manufacturing apparatus 2 Spring base material supply means 3 Metal wire supply means 4 Rotating electrode 5 Winding means 6 Spring base material reel 7 Spring base material 8 First detection sensor 9 Second detection sensor 10 Metal wire reel 11 Metal wire 14 Upper rotating electrode 15 Lower rotating electrode 16 Metal wire roller 17 Metal wire guide 18 Positioning unit 19 Abuttment unit 20 First pressing member 21 Second pressing member 22 Front side arm 23 Rear side arm 24 Bearing 25 Thrust roller 26 Elastic member 27 V-shaped guide groove 32 Elution part 33 Pusher 34 Lower limit position of the upper rotating electrode during welding 35 Top of the lower rotating electrode 36 Circular shape of the metal wire top 37 Finished product reel 40 Contact member

Claims

1. A method for manufacturing a contact member for an electric and electronic circuit, in which metal wires are stacked on a spring base material and welded, comprising: a spring base material supply step for supplying the spring base material to a rotating electrode including an upper rotating electrode and a lower rotating electrode; a metal wire supply step for supplying the metal wire to the rotating electrode; a contact member creating step of sandwiching the spring base material and the metal wire in a superposed state between the upper rotating electrode and the lower rotating electrode and continuously performing seam welding to produce a contact member for an electric and electronic circuit. In the contact member creating step, by pressing the spring base material against a reference surface of the rotating electrode, the position of the spring base material with respect to the rotating electrode is controlled, and the metal wire is guided by a V-shaped guide groove provided on the outer peripheral portion of the lower rotating electrode and positioned at a predetermined position of the spring base material and seam welded. A method for manufacturing a contact member for an electric and electronic circuit, characterized in that.

2. In the contact member creating step, with the spring base material and the metal wire sandwiched between the upper rotating electrode and the lower rotating electrode, the separation distance between the top of the lower rotating electrode and the surface of the spring base material is controlled within a predetermined range, and the metal wire and the spring base material are seam welded. The method for manufacturing a contact member for an electric and electronic circuit according to claim 1, characterized in that.

3. The method for manufacturing a contact member for an electric and electronic circuit according to claim 2, characterized in that the separation distance between the top of the lower rotating electrode and the surface of the spring base material is set by the angle and depth of the V-shaped guide groove provided on the outer peripheral portion of the lower rotating electrode.

4. The method for manufacturing a contact member for an electric and electronic circuit according to claim 2, characterized in that the separation distance between the top of the lower rotating electrode and the surface of the spring base material is in the range of 30 μm or more and 50 μm or less.

5. After the contact member creating step, further including an inspection step for inspecting the contact member for an electric and electronic circuit. The inspection step measures the amount of eluted portion where the outer edge of the welded portion where the spring base material and the metal wire are seam welded appears on the surface, and determines the quality based on the measured amount of the eluted portion. The method for manufacturing a contact member for an electric and electronic circuit according to claim 1, characterized in that.

6. Elution portion data indicating the relationship between the amount of the eluted portion and the generation state of the joint portion formed in the welded portion is acquired in advance. The manufacturing method of the contact member for an electric and electronic circuit according to claim 5, wherein a pass / fail determination is made based on the amount of the elution part according to the elution part data.

7. A manufacturing apparatus for a contact member for an electric and electronic circuit, which superposes and welds a metal wire on a spring base material, a spring base material supply means, a metal wire supply means, including an upper rotating electrode and a lower rotating electrode, sandwiching between the upper rotating electrode and the lower rotating electrode in a state where the spring base material supplied from the spring base material supply means and the metal wire supplied from the metal wire supply means are superposed, and a rotating electrode for continuously performing seam welding, a butting unit for controlling the position of the spring base material with respect to the rotating electrode by pressing the spring base material against a reference surface of the rotating electrode, the lower rotating electrode has a V-shaped guide groove provided on an outer peripheral portion, The manufacturing apparatus for a contact member for an electric and electronic circuit is characterized in that while maintaining a state in which the position of the spring base material with respect to the rotating electrode is controlled by the positioning unit, the metal wire is guided by a guide groove provided in the lower rotating electrode and positioned and seam-welded at a predetermined position of the spring base material.

8. When seam-welding the metal wire to the spring base material, it further includes a positioning unit for controlling the amount of deflection of the spring base material, the positioning unit has a first pressing member and a second pressing member that are separated by a predetermined distance and arranged opposite to each other, The manufacturing apparatus for a contact member for an electric and electronic circuit according to claim 7, wherein the amount of deflection of the spring base material is limited by the spring base material passing through a gap formed between the first pressing member and the second pressing member.

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