Solid-phase resistance spot bonding device

Abstract

To provide a solid-phase resistance spot bonding apparatus that can reduce labor through a simple configuration while suppressing a decrease in bonding quality. [Solution] The electrode 10, which includes one end 11 on one axial side and the other end on the other axial side, is configured to be movable between a first axial position and a second position further axially. A flow path 60 is provided in the inner space of the electrode 10, through which gas G supplied from a gas supply mechanism 40 can flow to one side in the axial direction. The flow path 60 includes a first path 61 located upstream, a second path 62 located downstream, and a connecting path 63 connecting them. The switching mechanism is configured to switch between a state in which the connection between the first path 61 and the second path 62 by the connecting path 63 is interrupted, and a state in which the first path 61 and the second path 62 are connected by the connecting path 63, in conjunction with the movement of the electrode 10 from the first position to the second position.

Description

Technical Field

[0001] The present invention relates to a solid-phase resistance spot joining apparatus.

Background Art

[0002] Conventionally, various methods for joining a plurality of workpieces are known. For example, Japanese Patent Laid-Open No. 8-47783 (Patent Document 1) and Japanese Patent Laid-Open No. 10-328851 (Patent Document 2) disclose resistance welding apparatuses for performing resistance welding as an example of the above methods. Further, International Publication No. 2021 / 182444 (Patent Document 3) discloses a solid-phase resistance spot joining apparatus for performing solid-phase resistance spot joining as another example of the above methods.

[0003] The resistance welding apparatuses disclosed in Patent Documents 1 and 2 described above are each provided with a gas supply mechanism capable of blowing gas to the vicinity of the contact portion between the workpiece and the electrode. This suppresses deterioration of joining quality caused by foreign matter such as dust being mixed between the electrode and the workpiece or the workpiece being overheated.

[0004] Further, in the resistance welding apparatus disclosed in Patent Document 2 described above, gas consumption is reduced by supplying gas only during joining, whereby labor saving of the apparatus is achieved. Specifically, in the resistance welding apparatus disclosed in Patent Document 2 described above, gas is supplied only during joining by controlling opening and closing of a solenoid valve provided in an air piping system with a control device.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Patent Document 3

Summary of Invention

[0006] Here, in the solid-phase resistance spot bonding apparatus disclosed in Patent Document 3, it is desirable that the apparatus be configured to supply gas only during bonding, as described above. On the other hand, if a configuration using the solenoid valve or the like is adopted, problems such as the apparatus becoming more complex and larger, and increased costs due to the increase in the number of parts will arise.

[0007] Therefore, the present invention has been made to solve the above-mentioned problems, and aims to provide a solid-phase resistance spot bonding apparatus that can reduce labor while suppressing a decrease in bonding quality with a simple configuration. [Means for solving the problem]

[0008] A solid-phase resistance spot bonding apparatus according to the present invention comprises a cylindrical electrode, a pressurizing shaft, a moving mechanism, and a gas supply mechanism. The electrode has one end located on one side in the axial direction and the other end located on the other side in the axial direction. The pressurizing shaft is provided inside the electrode and is capable of pressurizing the workpiece. The moving mechanism moves the electrode along the axial direction. The gas supply mechanism supplies gas to the inner space of the electrode. The one end includes a tip surface that is pressed against the workpiece. The electrode is configured to be movable between a first position in the axial direction and a second position which is on the other side of the axial direction from the first position. The inner space of the electrode is provided with a flow path through which the gas supplied by the gas supply mechanism can flow toward the one side in the axial direction. The flow path comprises a first path, a second path, and a connecting path. The first path is located upstream of the flow path. The second path is located downstream of the flow path. The above connection path connects the first path and the second path. The solid-phase resistance spot bonding apparatus according to the present invention further includes a switching mechanism configured to switch from a disconnected state in which the connection between the first path and the second path by the connection path is disconnected, to a connected state in which the first path and the second path are connected by the connection path, in conjunction with the movement of the electrode from the first position to the second position.

[0009] By configuring it in this way, a solid-phase resistance spot bonding apparatus can be created that is simple in structure, reduces labor, and suppresses a decrease in bonding quality.

[0010] In the solid-phase resistance spot bonding apparatus according to the present invention described above, a cam member may be provided in the inner space of the electrode, configured to move in a direction intersecting the axial direction by sliding contact with the electrode as it moves from the first position to the second position. In this case, the cam member may constitute the switching mechanism by having the connection path, and the blocking state may be achieved by positioning the cam member to block the space between the first path and the second path when the electrode is positioned at the first position, and the connecting state may be achieved by positioning the cam member to connect the first path and the second path when the electrode is positioned at the second position.

[0011] By configuring it in this way, the switching from a disconnected state to a connected state, which is linked to the movement of the electrode from the first position to the second position, can be achieved by a mechanical structure using a cam member.

[0012] In the solid-phase resistance spot bonding apparatus according to the present invention described above, the cam member may include an inclined surface that approaches the pressurizing shaft in a direction intersecting the axial direction as it approaches one side in the axial direction. In this case, the electrode moving from the first position to the second position may push the inclined surface, causing the cam member to move closer to the pressurizing shaft in a direction intersecting the axial direction, thereby switching from the disconnected state to the connected state. In this case, the cam member may be in contact with the pressurizing shaft in the connected state.

[0013] This configuration prevents the gas that has passed through the flow path from flowing back through the gap between the pressurizing shaft and the cam member.

[0014] In the solid-phase resistance spot bonding apparatus according to the present invention described above, an exhaust section may be provided at one end, comprising at least one of a notch and a through hole that penetrates the electrode in a direction intersecting the axial direction, and configured to discharge the gas supplied from the gas supply mechanism to the outside from the inner space of the electrode in the connected state.

[0015] With this configuration, it is possible to suppress a decrease in cooling efficiency caused by gas staying in the inner space of the electrode.

[0016] In the solid-phase resistance spot welding apparatus according to the present invention described above, a plurality of the exhaust portions may be provided in the circumferential direction of the electrode.

[0017] With this configuration, the gas is diffused in the in-plane direction of the workpiece, making it possible to efficiently cool the electrode and the workpiece. Effects of the Invention

[0018] According to the present invention, it is possible to provide a solid-phase resistance spot welding apparatus that can suppress a decrease in welding quality while achieving labor saving with a simple configuration. Brief Description of the Drawings

[0019] [Figure 1] It is a schematic diagram of the solid-phase resistance spot welding apparatus according to the embodiment. [Figure 2] It is a perspective view of the welding unit in the first state. [Figure 3] It is a schematic side view of the welding unit in the first state. [Figure 4] It is a schematic cross-sectional view of the welding unit shown in FIG. 3. [Figure 5] It is a schematic cross-sectional view of the welding unit shown in FIG. 3. [Figure 6] It is a schematic cross-sectional view for explaining switching from the first state to the second state. [Figure 7] It is a schematic cross-sectional view of the welding unit in the second state. Modes for Carrying Out the Invention

[0020] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the embodiments described below, the same or common parts are denoted by the same reference numerals in the drawings, and descriptions thereof will not be repeated.

[0021] (Embodiment) <A. Schematic Configuration of Solid-State Resistance Spot Welding Apparatus> FIG. 1 is a schematic diagram of the solid-state resistance spot welding apparatus according to the embodiment. Hereinafter, the schematic configuration of the solid-state resistance spot welding apparatus 1 according to the present embodiment will be described with reference to FIG. 1.

[0022] The solid-state resistance spot welding apparatus 1 is an apparatus used for so-called solid-state resistance spot welding, in which a plurality of workpieces are joined to each other in a solid state in a low temperature range without melting the workpieces. Specifically, the solid-state resistance spot welding apparatus 1 applies a voltage to a plurality of stacked workpieces to form softened regions therein, and applies a load to the plurality of workpieces in a state where the softened regions are formed, thereby plastically deforming the softened regions.

[0023] In the present embodiment, plate-shaped workpieces 301 and 302 are joined to each other by the solid-state resistance spot welding apparatus 1. The number of workpieces is not particularly limited to two, and may be three or more. In the present embodiment, the direction orthogonal to the in-plane direction of the workpieces 301 and 302 is also referred to as the Z-axis direction.

[0024] The workpieces 301 and 302 are made of, for example, a steel plate such as a high-tensile steel material. The workpieces 301 and 302 are not particularly limited to those made of a steel plate, and may be made of an aluminum plate or the like. Further, the workpieces 301 and 302 may be made of different materials such as a steel plate and an aluminum plate.

[0025] As shown in Figure 1, a solid-phase resistance spot welding apparatus 1 includes a pair of welding units 100 and a flexible conductor 200. The pair of welding units 100 are configured to press a plurality of stacked works so as to be able to clamp them and apply a voltage to these works. The flexible conductor 200 is configured to apply a voltage to the works 301 and 302.

[0026] Each of the pair of welding units 100 mainly has an electrode 10 and a pressurizing shaft 20 (see Figure 2 and the like described later). The pair of welding units 100 are attached to a gun arm (not shown) or the like, so as to be positioned coaxially and face each other in the Z-axis direction.

[0027] <B. Detailed Configuration of Welding Unit> Figure 2 is a perspective view of the welding unit in a first state. Figure 3 is a schematic side view of the welding unit in the first state. Figure 4 is a schematic cross-sectional view taken along the IV-IV line in Figure 3. Figure 5 is a schematic cross-sectional view taken along the V-V line in Figure 3. Hereinafter, the detailed configuration of the welding unit 100 included in the solid-phase resistance spot welding apparatus 1 according to the present embodiment will be described with reference to Figures 2 to 5. The first state will be described later.

[0028] As shown in Figures 2 to 5, the welding unit 100 includes an electrode 10, a pressurizing shaft 20, a moving mechanism 30, and a gas supply mechanism 40.

[0029] The electrode 10 has a substantially cylindrical shape. The electrode 10 is arranged around the pressurizing shaft 20 so as to be spaced apart from the pressurizing shaft 20 in the radial direction. The electrode 10 is configured to apply a voltage to the works 301 and 302. The material of the electrode 10 is, for example, copper.

[0030] The electrode 10 has one end 11 located on one side in the axial direction and another end 12 located on the other side in the axial direction. When the electrode 10 is assembled to the solid-phase resistance spot bonding apparatus 1, the axial direction coincides with the Z-axis direction. The other end 12 is held by the holder 50. Hereinafter, the one side of the electrode 10 in the axial direction will also be referred to as the Z1 side, and the other side of the electrode 10 in the axial direction will also be referred to as the Z2 side.

[0031] One end 11 includes a tip surface 11a that is pressed against the workpieces 301 and 302. The one end 11 is provided with a notch 11b that penetrates the electrode 10 in a direction intersecting the axial direction of the electrode 10. The notch 11b constitutes an exhaust section configured to allow the gas supplied from the gas supply mechanism 40 to be discharged from the inner space of the electrode 10 to the outside when connected. The connection state will be described later.

[0032] In this embodiment, eight notches 11b extending along the axial direction so as to reach the tip surface 11a are provided at equal intervals in the circumferential direction of the electrode 10. More specifically, the eight notches 11b are positioned at 45° rotationally symmetrical positions when viewed along the axial direction of the electrode 10.

[0033] Furthermore, the exhaust section is not limited to consisting only of a notch; it may consist of at least one of a notch and a through-hole that penetrate the electrode 10 in a direction intersecting the axial direction of the electrode 10. The number of exhaust sections is not particularly limited and may be one or more.

[0034] The inner circumferential surface of the electrode 10 includes a sliding contact surface 15 that is inclined to approach the pressurizing shaft 20 in a direction intersecting the Z-axis direction as it approaches the Z1 side. The sliding contact surface 15 is the part that slides against the inclined surface 71 of the cam member 70, which will be described in detail later.

[0035] The electrode 10 is configured to be movable along the Z-axis direction. More specifically, the electrode 10 is configured to be movable between a first axial position and a second position which is closer to the Z2 side than the first position by a moving mechanism 30. The configuration of the moving mechanism 30 is not particularly limited, but for example, a coil spring or an air cylinder may be used.

[0036] In this embodiment, a coil spring is used as the moving mechanism 30 to bias the electrode 10 toward the Z1 side. When a biasing member such as a coil spring is used, the electrode 10 can be moved from the first position to the second position by the reaction force from the workpieces 301 and 302 applied to the electrode 10 when the electrode 10 comes into contact with the workpieces 301 and 302.

[0037] Hereafter, the state in which the electrode 10 is positioned in the first axial position (see Figures 2 to 5) will also be referred to as the first state, and the state in which the electrode 10 is positioned in the second position (see Figures 6(C) and 7 described later) will also be referred to as the second state.

[0038] The pressurizing shaft 20 has a substantially cylindrical portion. The pressurizing shaft 20 causes plastic deformation of the stacked workpieces 301 and 302 by applying pressure along the Z-axis direction. The pressurizing shaft 20 is located inside the electrode 10.

[0039] The material of the pressurizing shaft 20 is, for example, tungsten carbide. However, the material of the pressurizing shaft 20 is not particularly limited to tungsten carbide, but may be tool steel, heat-resistant steel, ceramics, etc., as long as it can press the workpieces 301 and 302 in a way that allows for plastic deformation.

[0040] The gas supply mechanism 40 supplies gas G to the inner space of the electrode 10. The gas G supplied by the gas supply mechanism 40 flows through a flow path 60 provided in the inner space of the electrode 10. The flow path 60 is configured to allow gas G to flow toward the Z1 side.

[0041] The configuration of the gas supply mechanism 40 is not particularly limited, and for example, a device having a cylinder and nozzle, a blower or a compressor may be used. The type of gas G is not particularly limited, and for example, an inert gas such as argon or helium may be used, or compressed air may be used. In this embodiment, an inert gas is used as gas G.

[0042] The flow path 60 includes a first path 61 located upstream of the flow path 60, a second path 62 located downstream of the flow path 60, and a connecting path 63 that connects the first path 61 and the second path 62. In this embodiment, the downstream portion of the first path 61 and the upstream portion of the second path 62 are defined by the holder 50. The downstream portion of the second path 62 is defined by the inner circumferential surface of the electrode 10 and the circumferential surface of the pressurizing shaft 20. The downstream portion of the first path 61 and the second path 62 extend generally along the Z-axis direction.

[0043] The joining unit 100 further includes a cam member 70 configured to be movable in a direction intersecting the Z-axis direction. The cam member 70 has an elongated, substantially rectangular outer shape. Preferably, the cam member 70 is made of an insulating material.

[0044] The cam member 70 is assembled inside the holder 50 such that its longitudinal direction coincides with the radial direction of the electrode 10. A portion of the cam member 70 assembled in this manner is located in the inner space of the electrode 10. In this embodiment, the eight cam members 70 are arranged in positions that are 45° rotationally symmetrical when viewed along the axial direction of the electrode 10.

[0045] The cam member 70 is provided with a through-hole extending along the thickness direction (i.e., the Z-axis direction). The connection path 63 of the aforementioned flow path 60 is defined by the through-hole of the cam member 70.

[0046] The cam member 70 includes, at a portion adjacent to the inner peripheral surface of the electrode 10, an inclined surface 71 that is inclined so as to approach the pressurizing shaft 20 in the direction intersecting the Z-axis direction as it approaches the Z1 side. The inclined surface 71 is a portion that is in sliding contact with the sliding contact surface 15 of the electrode 10, and this point will be described in detail later.

[0047] <C. Solid-phase resistance spot welding> FIG. 6 is a schematic cross-sectional view for explaining switching from the first state to the second state. Specifically, FIG. 6(A) is a schematic cross-sectional view showing the joining unit in the first state, which is the same as FIG. 4 described above. FIG. 6(B) is a schematic cross-sectional view showing the joining unit in the transition process from the first state to the second state. FIG. 6(C) is a schematic cross-sectional view showing the joining unit in the second state. FIG. 7 is a schematic cross-sectional view of the joining unit in the second state. Next, with reference to FIG. 6 and FIG. 7, the solid-phase resistance spot welding using the solid-phase resistance spot welding apparatus 1 according to the present embodiment will be described. Note that FIG. 6 is a schematic cross-sectional view at a position corresponding to FIG. 4, and FIG. 7 is a schematic cross-sectional view at a position corresponding to FIG. 5.

[0048] As shown in FIG. 6(A), in the first state where the electrode 10 is disposed at the first position in the Z-axis direction, the portion of the cam member 70 other than the through portion is positioned so as to block between the first path 61 and the second path 62, whereby a disconnected state in which the connection between these paths is cut off is achieved. Therefore, in this state, the gas G supplied from the gas supply mechanism 40 is not supplied to the vicinity of the contact portion between the works 301, 302 and the electrode 10.

[0049] When joining the works 301 and 302 to each other using the solid-phase resistance spot welding apparatus 1, first, the tip surface 11a of the electrode 10 is pressed against the works 301 and 302. As a result, as shown in FIG. 6(B), the electrode 10 is moved to a position on the Z2 side relative to the first position. In this state, the position of the tip surface 11a of the electrode 10 in the Z-axis direction and the position of the tip end of the pressurizing shaft 20 are substantially the same. Further, in this state, the sliding contact surface 15 of the electrode 10 abuts on the inclined surface 71 of the cam member 70 disposed to face the sliding contact surface 15 in the Z-axis direction.

[0050] A voltage is applied to workpieces 301 and 302 by pressing the tip surface 11a of electrode 10 against them. This heats the workpieces 301 and 302, forming softened regions on them. The current supplied to workpieces 301 and 302 is, for example, 3.5kA to 10kA.

[0051] Next, a pair of pressurizing shafts 20 press against the workpieces 301 and 302 from both sides. The pressing force applied to the workpieces 301 and 302 by the pair of pressurizing shafts 20 is, for example, 30kN to 70kN.

[0052] When voltage is applied to workpieces 301 and 302 and they are pressed together in this manner, workpieces 301 and 302 are joined to each other in the softened region.

[0053] Here, the surfaces of workpieces 301 and 302 are deformed by the pressure of the pressurizing shaft 20. As a result, as shown in Figure 6(C), the electrode 10 is moved further towards Z2 so that its tip surface 11a follows the deformed surface of workpieces 301 and 302.

[0054] As the electrode 10 moves from the first position to the second position, which is Z2 closer to the first position, the sliding contact surface 15 of the electrode 10 comes into sliding contact with the inclined surface 71 of the cam member 70. As a result, the inclined surface 71 is pushed by the sliding contact surface 15, causing the cam member 70 to move closer to the pressurizing shaft 20 in a direction intersecting the Z-axis direction.

[0055] As a result, the system switches from the aforementioned blocked state to a connected state in which the connecting path 63 is positioned to connect the first path 61 and the second path 62. This ensures that the gas G supplied from the gas supply mechanism 40 is supplied to the vicinity of the contact area between the workpieces 301, 302 and the electrode 10 only in the second state in which the electrode 10 is positioned in the second position.

[0056] Here, as shown in FIG. 7, in the connected state, the end face of the cam member 70 located radially inward of the electrode 10 is in contact with the peripheral surface of the pressurizing shaft 20. As a result, substantially no gap is formed between the pressurizing shaft 20 and the cam member 70 at any position in the circumferential direction. As a result, the gas G that has flowed through the flow path 60 is suppressed from flowing backward through the gap between the pressurizing shaft 20 and the cam member 70.

[0057] Further, as shown in FIG. 6(C), in the connected state, the outer peripheral surface of the portion of the holder 50 that defines the upstream portion of the second path 62 is in contact with the inner peripheral surface of the electrode 10. As a result, substantially no gap is formed between the above portion of the holder 50 and the inner peripheral surface of the electrode 10 at any position in the circumferential direction. As a result, the gas G that has flowed through the flow path 60 is suppressed from flowing backward through the gap between the above portion of the holder 50 and the inner peripheral surface of the electrode 10.

[0058] In the above description, the case where the works 301 and 302 are pressed by the pressurizing shaft 20 after the electrode 10 is pressed against the works 301 and 302 has been illustrated, but these operations may be performed simultaneously.

[0059] <D. Subsection> As described above, in the present embodiment, the solid-phase resistance spot welding apparatus 1 is provided with a switching mechanism configured to be switched from the disconnected state to the connected state in conjunction with the movement of the electrode 10 from the first position to the second position. By providing such a switching mechanism, in the solid-phase resistance spot welding apparatus 1, gas is supplied from the gas supply mechanism 40 to the vicinity of the contact portion between the works 301, 302 and the electrode 10 only during welding.

[0060] By thus supplying the gas only during welding, the gas consumption is reduced, whereby labor saving of the apparatus is achieved.

[0061] Furthermore, in this embodiment, by incorporating the switching mechanism described above, it is possible to supply gas only during bonding without using electrical control such as solenoid valves or control devices. This configuration makes it possible to significantly simplify the device compared to cases where electrical control is used. As a result, it becomes possible to reduce the cost of the solid-phase resistance spot bonding apparatus 1.

[0062] Furthermore, by supplying gas near the contact area between the workpieces 301, 302 and the electrode 10 during joining, it is possible to suppress the deterioration of joining quality caused by foreign matter such as dust being mixed between the workpieces 301, 302 and the electrode 10, or by overheating of the workpieces 301, 302. In particular, when dissimilar materials such as iron-based materials and aluminum-based materials are joined, supplying gas as described above can effectively suppress the deterioration of joining quality caused by the growth of intermetallic compounds due to overheating of the workpieces 301, 302.

[0063] Furthermore, by supplying gas near the contact area between the workpieces 301 and 302 and the electrode 10 during bonding, the surfaces of the workpieces 301 and 302 can be kept clean. In addition, the electrode 10 and the components assembled thereto are cooled, which suppresses their wear and tear, and as a result, the lifespan of the solid-phase resistance spot bonding apparatus 1 is extended.

[0064] Therefore, by configuring the solid-phase resistance spot bonding apparatus 1 according to this embodiment, it is possible to reduce labor and suppress a decrease in bonding quality with a simple configuration.

[0065] Furthermore, in this embodiment, as described above, the switching mechanism is composed of a cam member 70. By configuring it in this way, gas can be supplied only during joining through a mechanical structure.

[0066] Furthermore, in this embodiment, as described above, an exhaust section is provided at one end 11. This configuration makes it possible to suppress the decrease in cooling efficiency caused by gas accumulating in the inner space of the electrode 10.

[0067] Furthermore, in this embodiment, as described above, multiple exhaust outlets are provided in the circumferential direction of the electrode 10. This allows the gas to diffuse in the in-plane direction of the workpieces 301 and 302, making it possible to cool the electrode 10 and the workpieces 301 and 302 more efficiently. This effect is more pronounced when the multiple exhaust outlets are arranged at equal intervals in the circumferential direction.

[0068] Furthermore, in this embodiment, as described above, an inert gas is used as the gas. This effectively suppresses oxidation of the surfaces of the workpieces 301 and 302.

[0069] In the above-described embodiment, the example given was that in the connected state, the end face of the cam member 70 located radially inward of the electrode 10 abuts against the circumferential surface of the pressurizing shaft 20. However, from the viewpoint of improving the sealing performance between them, a sealing ring made of rubber, for example, may be interposed between them.

[0070] Furthermore, in the embodiment described above, the connection state is illustrated by the electrode 10 moving in accordance with the deformation of the workpieces 301 and 302. However, the connection state may also be achieved when the tip surface 11a of the electrode 10 is pressed against the workpieces 301 and 302. In other words, the connection state may be achieved when the electrode 10 has moved from the first position to a predetermined position on the Z2 side such that the position of the tip surface 11a of the electrode 10 in the Z-axis direction and the position of the tip of the pressurizing shaft 20 are substantially the same. In this case, the predetermined position becomes the second position.

[0071] Furthermore, although the above-described embodiment illustrates a case where the cam member 70 constitutes a switching mechanism, the configuration of the switching mechanism is not limited to this. An example of another configuration of the switching mechanism is described below.

[0072] In one example of this other embodiment, the downstream portion of the first path 61 is positioned outside the electrode 10, and the upstream portion of the second path 62 is positioned inside the electrode 10. In addition, a hole is provided in a part of the electrode 10 that penetrates it. The connection path 63 is defined by the hole in the electrode 10.

[0073] In the first state, the portion of the electrode 10 other than the hole is positioned to block the space between the first path 61 and the second path 62, thereby interrupting the connection between them. When the electrode 10 moves from the first position to the second position, the connection path 63 defined by the hole in the electrode 10 is positioned to connect the first path 61 and the second path 62, switching to a connected state. In this embodiment, the electrode 10 constitutes a switching mechanism. Even with this configuration, effects similar to those described in the above-described embodiment can be obtained.

[0074] (Other forms, etc.) The shape, configuration, size, number, material, etc., of each part shown in the above-described embodiment can be modified in various ways as long as they do not depart from the spirit of the present invention.

[0075] Furthermore, the characteristic configurations shown in the above-described embodiments can naturally be combined with each other without departing from the spirit of the present invention.

[0076] Thus, the embodiments disclosed herein are illustrative in all respects and not restrictive. The technical scope of the present invention is defined by the claims and includes all modifications within the meaning and scope of equivalents to the claims. [Explanation of Symbols]

[0077] 1 Solid phase resistance spot bonding device, 10 Electrode, 11 One end, 11a Front end, 12 Other end, 20 Pressurizing shaft, 30 Moving mechanism, 40 Gas supply mechanism, 60 Flow path, 61 First path, 62 Second path, 63 Connection path, 70 Cam member, 71 Inclined surface, 301, 302 Workpiece.

Claims

1. A cylindrical electrode having one end located on one side in the axial direction and the other end located on the other side in the axial direction, A pressurizing shaft is provided inside the electrode and capable of pressurizing the workpiece, A moving mechanism for moving the electrode along the axial direction, The system includes a gas supply mechanism that supplies gas to the inner space of the electrode, The aforementioned end includes a tip surface that is pressed against the workpiece, The electrode is configured to be movable between a first position in the axial direction and a second position which is on the other side of the axial direction from the first position. The inner space of the electrode is provided with a flow path through which the gas supplied by the gas supply mechanism can flow toward one side in the axial direction. The flow path comprises a first path located upstream of the flow path, a second path located downstream of the flow path, and a connecting path that connects the first path and the second path. A solid-phase resistance spot bonding apparatus further comprising a switching mechanism configured to switch from a disconnected state, in which the connection between the first and second paths by the connection path is interrupted, to a connected state, in which the first and second paths by the connection path are connected, in conjunction with the movement of the electrode from the first position to the second position.

2. A cam member is provided in the inner space of the electrode, which is configured to move in a direction intersecting the axial direction by sliding in contact with the electrode as it moves from the first position to the second position. The solid-phase resistance spot bonding apparatus according to claim 1, wherein the cam member constitutes the switching mechanism by having the connection path, the blocking state is achieved by positioning the cam member to block the space between the first path and the second path when the electrode is positioned in the first position, and the connecting state is achieved by positioning the cam member to connect the first path and the second path when the electrode is positioned in the second position.

3. The cam member includes an inclined surface that, as it approaches one side in the axial direction, approaches the pressurizing shaft in a direction intersecting the axial direction, The electrode, moving from the first position to the second position, presses against the inclined surface, causing the cam member to move closer to the pressurizing shaft in a direction intersecting the axial direction, thereby switching from the disconnected state to the connected state. The solid-phase resistance spot bonding apparatus according to claim 2, wherein in the aforementioned connection state, the cam member is in contact with the pressure shaft.

4. The solid-phase resistance spot bonding apparatus according to any one of claims 1 to 3, wherein the one end is provided with an exhaust section comprising at least one of a notch and a through hole that penetrates the electrode in a direction intersecting the axial direction, and configured to discharge the gas supplied from the gas supply mechanism outwards from the inner space of the electrode in the connected state.

5. The solid-phase resistance spot bonding apparatus according to claim 4, wherein the exhaust section is provided in multiple locations in the circumferential direction of the electrode.

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