Solid-phase resistance point bonding device

Abstract

The present invention provides a solid-phase resistance spot bonding device capable of easily changing the pressure applied to an electrode. This solid-phase resistance spot bonding device is provided with a pressing shaft, an electrode, and a drive mechanism. The drive mechanism is capable of moving the electrode relative to the pressing shaft in the axial direction. The driving mechanism comprises a working cylinder and a piston. The cylinder is fixed to the pressurizing shaft so as to surround the pressurizing shaft, and has an inner peripheral surface extending in the axial direction. The piston is connected to the electrode, is housed in the cylinder, and is driven by the pressure of the fluid. The piston divides the internal space of the cylinder into a first chamber and a second chamber. The fluid alternately enters and exits the first chamber and the second chamber, so that the piston slides relative to the inner circumferential surface and is driven in the axial direction, thereby enabling the electrode to move together with the piston in the axial direction.

Description

Technical Field

[0001] This invention relates to a solid-state resistance point bonding device. Background Technology

[0002] Japanese Patent Application Publication No. 2024-8499 discloses the structure of a solid-state resistive bonding device. The solid-state resistive bonding device described in Japanese Patent Application Publication No. 2024-8499 includes a pressure shaft, electrodes, and an elastic member. The pressure shaft presses multiple overlapping objects to be bonded in a manner capable of plastic deformation. Electrodes are arranged around the pressure shaft and apply a voltage to the multiple objects to be bonded. The elastic member applies force to the electrodes toward the multiple objects to be bonded.

[0003] Japanese Patent Application Publication No. 2022-74258 discloses the structure of a rotary pressing device for rotary friction welding. The rotary pressing device described in Japanese Patent Application Publication No. 2022-74258 performs rotary friction welding of a pin to a workpiece. The rotary pressing device includes a pressing mechanism. The pressing mechanism applies a pressing force to the pin using a hydraulic cylinder.

[0004] In addition, as prior art, there is Japanese Patent No. 5204928, which discloses a working cylinder structure similar to that in Japanese Patent Application Publication No. 2022-74258. Summary of the Invention

[0005] The solid-state resistive bonding device described in Japanese Patent Application Publication No. 2024-8499 requires replacement of the elastic member each time the electrode pressure is changed in order to obtain the necessary pressure. If the electrode pressure is changed frequently, the operation time for changing the electrode pressure may increase.

[0006] In devices other than solid-state resistance bonding devices disclosed in Japanese Patent Application Publication No. 2022-74258 and Japanese Patent No. 5204928, a working cylinder structure driven by fluid pressure is disclosed. There is potential to apply this working cylinder structure to the setting of the pressure applied to the electrodes in a solid-state resistance bonding device.

[0007] The present invention was made to solve the above-mentioned problems, and its purpose is to provide a solid-state resistive bonding device that allows for easy variation of the applied pressure of the electrodes.

[0008] The solid-state resistive bonding apparatus according to the present invention includes a pressure shaft, electrodes, and a drive mechanism. The pressure shaft presses multiple overlapping bonding materials axially in a manner capable of plastic deformation. Electrodes are disposed around the pressure shaft and apply voltage to the bonding materials. The drive mechanism enables the electrodes to move relative to the pressure shaft in the aforementioned axial direction. The drive mechanism includes a working cylinder and a piston. The working cylinder is fixed to the pressure shaft in a manner surrounding the pressure shaft and has an inner circumferential surface extending along the aforementioned axial direction. The piston is connected to the electrodes and housed in the working cylinder, and is driven by fluid pressure. The piston divides the internal space of the working cylinder into a first chamber and a second chamber. By alternately flowing fluid into and out of the first and second chambers, the piston slides relative to the inner circumferential surface and is driven along the aforementioned axial direction, thereby enabling the electrodes to move together with the piston along the aforementioned axial direction.

[0009] In this case, compared to using an elastic member to drive the electrode, there is no need to replace the elastic member each time the electrode pressure is changed, thus reducing the operation time for changing the electrode pressure. As a result, the solid-state resistor point bonding device can easily change the electrode pressure.

[0010] In one aspect of the invention, the working cylinder and the piston each have an insulating portion to insulate the pressure shaft from the electrode.

[0011] Therefore, the pressure shaft can be insulated from the electrodes, thus suppressing the bonding between the pressure shaft and multiple objects being joined while a voltage is applied to the pressure shaft.

[0012] In one embodiment of the invention, the piston has a rod and a flange. The rod extends along the aforementioned axial direction, and one end of the axial direction is connected to an electrode. The flange extends radially from the other end of the rod in a direction orthogonal to the aforementioned axial direction and abuts against an inner circumferential surface. A first chamber is located on the rod side when viewed from the flange. A second chamber is located on the side opposite to the rod side when viewed from the flange. A through hole is provided in the rod and the flange along the aforementioned axial direction. The hole is sealed when the pressure shaft is inserted through it. The second chamber is surrounded by a working cylinder, the flange, and the pressure shaft.

[0013] In this case, by setting the drive mechanism as a single-bar mechanism, compared to a two-bar mechanism, it is possible to utilize the pressure shaft to surround a portion of the second chamber, thus eliminating the need for a portion of the working cylinder structure. As a result, the drive mechanism can be miniaturized, thereby enabling the miniaturization of the solid-state resistance point bonding device.

[0014] In one aspect of the invention, the working cylinder has a metal bushing that forms an inner circumferential surface and slides relative to the piston.

[0015] This improves the durability of the drive mechanism.

[0016] The solid-state resistance bonding device in one embodiment of the invention further includes a sleeve. The sleeve is configured to seal the gap between the pressure shaft and the electrode and is insulating. The sleeve is slidable relative to the pressure shaft or the electrode.

[0017] Therefore, it is possible to suppress sputtering material from solid-state resistor junctions from entering the interior of the drive mechanism, thus enabling the drive mechanism to operate stably.

[0018] The above and other objects, features, aspects and advantages of the present invention will become clear from the following detailed description relating to the invention, which is understood in conjunction with the accompanying drawings. Attached Figure Description

[0019] Figure 1 This is a front view showing the structure of a solid-state resistive point bonding device according to an embodiment of the present invention.

[0020] Figure 2 This is a perspective view showing the structure of a joining unit according to an embodiment of the present invention.

[0021] Figure 3 Observe from the direction of the arrow on line III-III Figure 2 A cross-sectional view of the structure of the joining unit.

[0022] Figure 4 It is a cross-sectional view showing the state in which the electrode is pushed towards the object being joined by the driven mechanism.

[0023] Figure 5 This is a cross-sectional view showing the structure of the drive mechanism of the solid-state resistive bonding device of the comparative example. Detailed Implementation

[0024] Hereinafter, a solid-state resistive bonding device according to an embodiment of the present invention will be described with reference to the accompanying drawings. In the following description of the embodiment, the same or equivalent parts in the drawings will be labeled with the same reference numerals, and their descriptions will not be repeated.

[0025] It should be noted that, in the attached drawings, the direction orthogonal to the axial direction of the pressure shaft and parallel to the extension direction of the connecting conductor is designated as the X direction. Furthermore, the axial direction of the pressure shaft is designated as the Y direction. And, the direction orthogonal to both the axial direction of the pressure shaft and the extension direction of the connecting conductor is designated as the Z direction.

[0026] Figure 1 This is a front view showing the structure of a solid-state resistive point bonding device according to an embodiment of the present invention.

[0027] like Figure 1As shown, a solid-state resistive bonding device 1 according to an embodiment of the present invention is a device that holds multiple objects 2 together in a solid state by passing current through multiple overlapping objects 2 to form a softened region on the multiple objects 2 and plastically deforming the softened region.

[0028] The solid-state resistance point bonding device 1 includes a bonding unit 10 and another bonding unit 20.

[0029] The joining unit 10 is a unit used to press multiple objects 2 together in a manner capable of plastic deformation and to apply voltage to the multiple objects 2 together. The joining unit 10 is driven axially (Y direction) by a drive source such as a servo press (not shown). The structure of the joining unit 10 will be described later.

[0030] Another bonding unit 20 is used to press together with bonding unit 10 a plurality of bonded objects 2 and to apply voltage to the plurality of bonded objects 2. The other bonding unit 20 is fixed to a housing (not shown) of the solid-state resistance point bonding device 1.

[0031] In this embodiment, the other joining unit 20 has the same structure as the joining unit 10, symmetrically positioned relative to the joining unit 10 with the XZ plane as a reference. It should be noted that the other joining unit 20 is not limited to this structure; for example, it may also be a structure without the drive mechanism 120 described later.

[0032] A power supply unit (not shown) applies voltage to both the bonding unit 10 and the other bonding unit 20. Voltage is applied to the bonding unit 10 from the connecting conductor 150 (described later). Voltage is also applied to the other bonding unit 20 from the connecting conductor.

[0033] The material to be joined by the solid-state resistance bonding device 1 is, for example, a steel plate made of high tensile strength. It should be noted that the material to be joined 2 is not limited to a steel plate, but may also be an aluminum plate, or a dissimilar material of steel and aluminum.

[0034] The joining unit 10 will be described below. Figure 2 This is a perspective view showing the structure of a joining unit according to an embodiment of the present invention. Figure 3 Observe from the direction of the arrow on line III-III Figure 2 The cross-sectional view is obtained by considering the structure of the joining unit.

[0035] like Figure 2 as well as Figure 3 As shown, in one embodiment of the present invention, the bonding unit 10 includes a pressure shaft 100, an electrode 110, a drive mechanism 120, a connecting conductor 150, a plate-shaped member 151, a wiring member 152, and a sleeve 160.

[0036] The pressure shaft 100 presses the overlapping multiple objects 2 from the axial direction (Y direction) in a manner that allows for plastic deformation. Specifically, in this embodiment, the pressure shaft 100 presses the multiple objects 2 with a pressing force of 30 to 50 kN by being driven by a drive source.

[0037] The pressure shaft 100 in this embodiment has a main shaft 101 and a tubular member 103. It should be noted that the pressure shaft 100 can also be a structure in which the main shaft 101 and the tubular member 103 are integrated.

[0038] The spindle 101 is a cylindrical member extending along the Y direction. The material of the spindle 101 is, for example, tungsten carbide. However, the material of the spindle 101 is not particularly limited as long as it can apply the necessary pressing force to the joined objects 2, and can also be tool steel, heat-resistant steel, or ceramics, etc.

[0039] The main shaft 101 has a front end 105 and a rear end 106. The front end 105 is connected to the joint 2A located on the side of the joint unit 10 among the plurality of jointed objects 2 (see reference). Figure 1 The contact portion. The rear end 106 is connected to the tubular member 103. The rear end 106 has a tapered shape and engages with the inner circumferential surface of the tubular member 103.

[0040] In this embodiment, the spindle 101 is composed of two components with a replaceable front end. It should be noted that the spindle 101 is not limited to this structure and may also be composed of a single component.

[0041] The tubular member 103 is a component that supports the main shaft 101. The tubular member 103 is made of, for example, steel.

[0042] The tubular member 103 has a cylindrical portion 107 and a flange portion 108. The cylindrical portion 107 extends along the Y direction. The cylindrical portion 107 has a tapered inner circumferential surface at its front end. The flange portion 108 extends radially from the upper end of the cylindrical portion 107 in the XZ plane. The flange portion 108 is fixed to the connecting conductor 150.

[0043] Electrode 110 and pressure shaft 100 are driven together in the Y direction by a drive source. Electrode 110 is spaced apart from pressure shaft 100 and disposed around pressure shaft 100. In this embodiment, the front end 111 of electrode 110 has a cylindrical shape when viewed from the Y direction.

[0044] Electrode 110 applies a voltage to a plurality of substrates 2. By applying a voltage to the plurality of substrates 2, electrode 110 heats the plurality of substrates 2 by passing a current of 3500 to 10000 A through the substrates 2. Electrode 110 is made of, for example, copper.

[0045] In this embodiment, the electrode 110 is composed of two components such that the front end portion is replaceable. It should be noted that the electrode 110 is not limited to this structure and may also be composed of a single component.

[0046] The connecting conductor 150 is fixed in a state of insulation from the tubular member 103. The plate member 151 is conductive and connected to the peripheral surface of the electrode 110. The wiring member 152 electrically connects the connecting conductor 150 and the plate member 151. The wiring member 152 is made of, for example, copper wire.

[0047] For the current supplied from the power source, the current flows in the order of connecting conductor 150, wiring member 152, plate member 151, and electrode 110, and flows to the bonded object 2. In the solid-state resistive bonding device 1, by pressing the pressure shaft 100 and the electrode 110 against the bonded object 2, the bonded objects 2A and 2B are pressed tightly against each other at the contact surface, thereby reducing the contact resistance. As a result, the contact surface with reduced contact resistance becomes a current-carrying path, and current flows to this current-carrying path.

[0048] The drive mechanism 120 enables the electrode 110 to move relative to the pressure shaft 100 in the axial direction (Y direction). The drive mechanism 120 is driven by the pressure of a fluid. In this embodiment, the drive mechanism 120 is driven by the pressure of air. It should be noted that the drive mechanism 120 is not limited to an air-based drive method, but can also be driven by the pressure of other fluids such as hydraulic fluid.

[0049] The drive mechanism 120 includes a working cylinder 130 and a piston 140.

[0050] The working cylinder 130 is fixed to the pressure shaft 100 in a manner that surrounds the pressure shaft 100. The working cylinder 130 surrounds the entire circumference of the pressure shaft 100 in the Y direction. The working cylinder 130 is fixed to the pressure shaft 100, for example, by bolt fastening. The working cylinder 130 is fixed to the flange portion 108 of the tubular member 103 in the pressure shaft 100.

[0051] The working cylinder 130 has a cylinder head 131, a bushing 132, and a cylinder rod 133.

[0052] The cylinder head 131 is a plate-shaped member extending in the XZ plane. The cylinder head 131 abuts against the flange 108 of the tubular member 103 in the Y direction. A hole 134 extending in the Y direction is provided in the cylinder head 131. The tubular member 103 in the pressure shaft 100 is inserted through the hole 134 provided in the cylinder head 131.

[0053] The bushing 132 is disposed on the electrode 110 side of the cylinder head 131. The bushing 132 is clamped between the cylinder head 131 and the cylinder rod 133.

[0054] Bushing 132 is a cylindrical member extending along the axial direction (Y direction). Bushing 132 has an inner circumferential surface 135 extending along the axial direction (Y direction). That is, bushing 132 forms the inner circumferential surface 135 in the working cylinder 130. Bushing 132 is made of metal. Bushing 132 slides relative to piston 140.

[0055] The cylinder rod 133 is a plate-shaped member extending in the XZ plane. The cylinder rod 133 is disposed on the electrode 110 side of the bushing 132. A hole 136 extending in the Y direction is provided in the cylinder rod 133. A pressure shaft 100 and a piston 140 are inserted through the hole 136 in the cylinder rod 133.

[0056] An inner bushing 137 is provided in the hole 136 of the cylinder rod 133. The inner bushing 137 is made of metal. The inner bushing 137 slides relative to the rod portion 141 of the piston 140, which will be described later.

[0057] Piston 140 is connected to electrode 110 and housed in working cylinder 130. Piston 140 is driven by fluid pressure. In this embodiment, piston 140 is driven by air pressure.

[0058] The piston 140 has a rod portion 141 and a flange portion 142. The drive mechanism 120 in this embodiment has a so-called single-rod structure in which a rod portion 141 is provided on one side of the flange portion 142.

[0059] The rod portion 141 has a cylindrical shape. The rod portion 141 extends along the axial direction (Y direction). One end of the rod portion 141 along the axial direction (Y direction) is connected to the electrode 110. The rod portion 141 is connected to the electrode 110 by screwing it into the electrode 110.

[0060] The flange portion 142 extends radially from the other end of the rod portion 141 in a direction orthogonal to the axial direction. In this embodiment, the flange portion 142 extends radially in the XZ plane. The flange portion 142 abuts against the inner peripheral surface 135.

[0061] A hole 143 extending axially (Y direction) is provided in the rod portion 141 and the flange portion 142. A pressure shaft 100 is inserted through the hole 143. The piston 140 is configured to be supported by the outer peripheral surface 109 of the pressure shaft 100. The hole 143 is sealed in the state where the pressure shaft 100 is inserted.

[0062] The working cylinder 130 and piston 140 each have an insulating portion to insulate the pressure shaft 100 from the electrode 110. In this embodiment, the working cylinder 130 and piston 140 each have an insulating portion by being made of an insulating material. The working cylinder 130 and piston 140 are each made of, for example, phenolic resin. It should be noted that the working cylinder 130 and piston 140 may also be made of metal coated with an insulating material.

[0063] The drive mechanism 120 is provided with an inner liner 121, an outer liner 122, a ring member 123, an upper liner 124, and a lower liner 125.

[0064] An inner gasket 121 is disposed on the wall of the hole 143. The inner gasket 121 is disposed to seal the hole 143 when the pressure shaft 100 is inserted.

[0065] The inner liner 121 has at least two portions along the axial direction (Y direction). In this embodiment, the two inner liner 121 are spaced apart from each other and arranged along the axial direction (Y direction). As a result, the piston 140 is supported relative to the pressure shaft 100 in the Y direction. Consequently, tilting of the piston 140 in the Y direction or positional offset (eccentricity) of the piston 140 relative to the pressure shaft 100 can be suppressed.

[0066] An outer gasket 122 and a ring member 123 are disposed on the outer periphery of the flange portion 142. The outer gasket 122 seals the inner peripheral surface 135 of the working cylinder 130 with the flange portion 142 of the piston 140. The ring member 123 assists in the sliding of the inner peripheral surface 135 with the flange portion 142. The ring member 123 can be made of metal or resin. When the ring member is made of resin, it is desirable that the resin is a resin with relatively high strength, such as phenolic resin. Therefore, compared with a metal ring member, a resin ring member is more likely to suppress sintering or jamming during sliding.

[0067] The upper gasket 124 is disposed on the cylinder head 131. The upper gasket 124 seals the space between the pressure shaft 100 and the drive mechanism 120.

[0068] The upper gasket 124 is disposed on the upper end face of the cylinder head 131 in the Y direction. Assuming that the upper gasket 124 is disposed on the wall of the hole 134 in the cylinder head 131, to ensure the sealing function of the upper gasket 124, there is a possibility that the sealing function of the inner gasket 121 may become insufficient due to manufacturing tolerances and other factors between the upper gasket 124 and the inner gasket 121. Therefore, by disposing the upper gasket 124 on the upper end face of the cylinder head 131 in the Y direction, neither the upper gasket 124 nor the inner gasket 121 is disposed along the outer peripheral surface 109. As a result, the influence of the upper gasket 124 on the sealing function of the inner gasket 121 is suppressed, thereby improving the airtightness of the internal space of the drive mechanism 120.

[0069] The lower gasket 125 is disposed on the wall surface of the hole 136 of the cylinder rod 133. The lower gasket 125 seals the space between the rod portion 141 and the cylinder rod 133.

[0070] The internal space of the working cylinder 130 is sealed by the inner gasket 121, the upper gasket 124 and the lower gasket 125.

[0071] The piston 140 divides the internal space of the working cylinder 130 into a first chamber 11 and a second chamber 12. The first chamber 11 is located on the rod 141 side when viewed from the flange 142. The second chamber 12 is located on the opposite side to the rod 141 side when viewed from the flange 142.

[0072] The first chamber 11 is connected to the first supply path 15. The first supply path 15 is configured to penetrate the interior of the cylinder rod 133. Air can be supplied to the first chamber 11 from the first supply path 15. In addition, the air in the first chamber 11 can be discharged from the first supply path 15.

[0073] The second chamber 12 is connected to the second supply path 16. The second supply path 16 is configured to penetrate the interior of the cylinder head 131. Air can be supplied to the second chamber 12 from the second supply path 16. In addition, air located in the second chamber 12 can be discharged from the second supply path 16.

[0074] The sleeve 160 is configured to seal the gap between the pressure shaft 100 and the electrode 110. The sleeve 160 is insulating.

[0075] The sleeve 160 is slidable relative to the pressure shaft 100 or the electrode 110. In this embodiment, the sleeve 160 is fitted into the pressure shaft 100. Thus, the sleeve 160 is slidable relative to the electrode 110.

[0076] Figure 4 It is a cross-sectional view showing the state in which the electrode is pushed towards the object being joined by the driven mechanism.

[0077] like Figure 3 as well as Figure 4 As shown, by the alternating flow of fluid into and out of the first chamber 11 and the second chamber 12, the piston 140 slides relative to the inner circumferential surface 135 and is driven axially (Y direction). Thus, the electrode 110 can move axially (Y direction) together with the piston 140.

[0078] like Figure 1 , Figure 3 as well as Figure 4 As shown, the operation of the solid-state resistance bonding device 1 begins with the drive mechanism 120 moving the electrode 110 toward the plurality of objects 2 to be bonded. Specifically, air is expelled from the first chamber 11 of the working cylinder 130, and air is supplied to the second chamber 12. The first chamber 11 narrows, and the second chamber widens. Consequently, with the drive of the piston 140, the electrode 110 moves toward the objects 2 to be bonded. Figure 4 (DR1 direction in the diagram). The maximum movement distance of electrode 110 is, for example, 8 mm.

[0079] Next, the bonding unit 10 is driven by a drive source, causing the electrode 110 to abut against the bonding member 2A located on the side of the bonding unit 10 among the plurality of bonding members 2. By applying preload by bringing the electrode 110 into contact with the bonding member 2A ahead of the pressure shaft 100, temporary positioning of the bonding member 2 is achieved. Meanwhile, the electrode of another bonding unit 20 abuts against the bonding member 2B among the plurality of bonding members 2.

[0080] Next, under the pressure of the drive mechanism 120, the electrode 110 is pressed against the plurality of objects to be joined 2, and the pressure shaft 100 is pressed against the plurality of objects to be joined 2. The electrode 110 is retracted while being pressurized by air until the pressure shaft 100 abuts against the plurality of objects to be joined 2.

[0081] Next, a voltage is applied from electrode 110 to the plurality of bonded objects 2. The contact surfaces of the bonded objects 2, where the contact resistance is reduced due to their close contact with each other, become a current-carrying path, and current flows through this path. As a result, the plurality of bonded objects 2 are heated, forming a softened region between them.

[0082] By pressing with a pressure shaft 100 while energizing the workpiece 2 from the electrode 110, the softened region of the workpiece 2 is plastically deformed. Through the plastic deformation of the softened region, a new surface is formed in the softened region. The new surfaces abut against each other, thereby the workpieces 2A and 2B are joined together by solid-state resistance points.

[0083] It should be noted that there is no limitation on the order in which the pressure shaft 100 and the electrode 110 come into contact with the object 2. The pressure shaft 100 may come into contact with the object 2 before the electrode 110, or the pressure shaft 100 and the electrode 110 may come into contact with the object 2 simultaneously.

[0084] The solid-state resistor bonding device of the comparative example will now be described. The structure of the drive mechanism of the solid-state resistor bonding device of the comparative example differs from the structure of the drive mechanism of the solid-state resistor bonding device 1 of an embodiment of the present invention; therefore, structures identical to those of the solid-state resistor bonding device 1 of an embodiment of the present invention will not be described again.

[0085] Figure 5 This is a cross-sectional view showing the structure of the drive mechanism included in the comparative example solid-state resistive bonding device. It should be noted that... Figure 5 The detailed connection details of each structure are omitted.

[0086] like Figure 5As shown, the comparative example solid-state resistance bonding device 1A includes a pressure shaft 200, an electrode 210, and a drive mechanism 220. The drive mechanism 220 includes a working cylinder 230 and a piston 240. The working cylinder 230 has a cylinder head 231, a bushing 232, and a cylinder rod 233.

[0087] The piston 240 of the comparative example has a first rod portion 241, a flange portion 242, and a second rod portion 244. The drive mechanism 220 in this comparative example has a so-called two-rod structure with rod portions provided on both sides of the flange portion 242.

[0088] In the comparative example, the second chamber 22 is divided by the working cylinder 230 and the piston 240. Since the cylinder head 231 and the second rod portion 244 are arranged in the XZ plane, the size of the drive mechanism 220 tends to be relatively large in the XZ plane.

[0089] On the other hand, such as Figure 3 as well as Figure 4 As shown, the drive mechanism 120 in one embodiment is a so-called single-bar structure. Therefore, the second chamber 12 is surrounded by the working cylinder 130, the flange portion 142, and the pressure shaft 100. Compared with the two-bar structure drive mechanism 220 in the comparative example, the drive mechanism 120 in one embodiment can be miniaturized by using the pressure shaft 100 to surround a part of the second chamber 12, thereby omitting a part of the structure of the working cylinder 130 (the second bar portion 244 in this comparative example).

[0090] In the solid-state resistance bonding apparatus 1 of this embodiment, the electrode 110 is moved using a drive mechanism 120 that utilizes the pressure of a fluid (air in this embodiment). Therefore, the required pressure applied to the electrode 110 can be changed by adjusting the fluid pressure. Compared to the case where the electrode 110 is driven using an elastic member, the solid-state resistance bonding apparatus 1 eliminates the need to replace the elastic member each time the pressure of the electrode 110 is changed, thus reducing the operation time for changing the pressure of the electrode 110. As a result, the solid-state resistance bonding apparatus 1 allows for easy changing of the pressure applied to the electrode 110.

[0091] In the solid-state resistance bonding device 1 of this embodiment, the working cylinder 130 and the piston 140 each have an insulating part, thereby insulating the pressure shaft 100 from the electrode 110. Therefore, it is possible to suppress the bonding of the pressure shaft 100 with the plurality of bonded objects 2 while applying voltage to the pressure shaft 100.

[0092] In the case where the drive mechanism 120 is composed of insulating components, it is conceivable that a material with lower rigidity than metal, such as resin, is used in the insulating components. In this case, the drive mechanism 120 is prone to be enlarged in order to ensure sufficient rigidity. In this embodiment, the pressure shaft 100 is a structure that supports the piston 140 of the drive mechanism 120. Therefore, by considering the pressure shaft 100 and the piston 140 as a single unit, the rigidity of the piston 140 can be ensured, and thus the size of the piston 140 can be reduced compared to the size required to ensure rigidity as a single unit. As a result, the drive mechanism 120 can be miniaturized.

[0093] In the solid-state resistance bonding apparatus 1 of this embodiment, the drive mechanism 120 is configured as a single-bar mechanism. Therefore, compared to the case where only a working cylinder and piston are used to regulate the fluid in the containment chamber (a two-bar mechanism), the pressure shaft 100 can surround the first chamber 11 (which serves as an air containment chamber) and a portion of the second chamber 12, thus eliminating the need for a portion of the working cylinder 130. As a result, the drive mechanism 120 can be miniaturized. Furthermore, the solid-state resistance bonding apparatus 1 can be miniaturized.

[0094] In the solid-state resistance point bonding device 1 of this embodiment, the working cylinder 130 has a metal bushing 132 that slides relative to the piston 140, thereby improving the durability of the drive mechanism 120 by arranging the metal bushing 132 at the sliding part of the piston 140.

[0095] In the solid-state resistor bonding apparatus 1 of this embodiment, a sleeve 160 is provided to seal the gap between the pressure shaft 100 and the electrode 110 and to slide relative to the electrode 110. This prevents sputtering material from entering the drive mechanism 120 during solid-state resistor bonding, thus enabling the drive mechanism 120 to drive stably. Furthermore, by positioning the electrode 110 using the sleeve 160, eccentricity of the electrode 110 relative to the pressure shaft 100 can be suppressed.

[0096] [Postscript]

[0097] As described above, this embodiment includes the following disclosures.

[0098] [Structure 1]

[0099] A solid-state resistive point bonding device (1), wherein,

[0100] The solid-state resistance bonding device (1) comprises:

[0101] A pressure shaft (100) presses multiple overlapping joints (2) from the axial direction in a manner capable of plastic deformation;

[0102] Electrodes (110), which are disposed around the pressure shaft (100), apply voltage to the plurality of coupled objects (2); and

[0103] A drive mechanism (120) enables the electrode (110) to move relative to the pressure shaft (100) in the axial direction.

[0104] The drive mechanism (120) includes:

[0105] A working cylinder (130), which is fixed to the pressure shaft (100) in a manner surrounding the pressure shaft (100), and has an inner circumferential surface (135) extending along the axial direction; and

[0106] A piston (140), which is connected to the electrode (110) and housed in the working cylinder (130), is driven by fluid pressure.

[0107] The piston (140) divides the internal space of the working cylinder (130) into a first chamber (11) and a second chamber (12).

[0108] By alternating the flow of fluid into and out of the first chamber (11) and the second chamber (12), the piston (140) slides relative to the inner circumferential surface (135) and is driven along the axial direction, thereby enabling the electrode (110) to move along the axial direction together with the piston (140).

[0109] [Structure 2]

[0110] According to the solid-state resistance point bonding device (1) described in structure 1, wherein...

[0111] The working cylinder (130) and the piston (140) each have an insulating portion to insulate the pressure shaft (100) from the electrode (110).

[0112] [Structure 3]

[0113] According to the solid-phase resistance point bonding device (1) described in structure 1 or structure 2, wherein...

[0114] The piston (140) has:

[0115] A rod (141) extending along the axial direction, with one end of the axial direction connected to the electrode (110); and

[0116] A flange (142) extends radially from the other end of the axial direction of the rod (141) in a direction orthogonal to the axial direction and abuts against the inner circumferential surface (135).

[0117] The first chamber (11) is located on the side of the rod (141) when viewed from the flange portion (142).

[0118] The second chamber (12) is located on the side opposite to the rod (141) when viewed from the flange (142).

[0119] The rod portion (141) and the flange portion (142) are provided with holes (143) that extend along the axial direction.

[0120] The hole (143) is sealed when it is penetrated by the pressure shaft (100).

[0121] The second chamber (12) is surrounded by the working cylinder (130), the flange (142) and the pressure shaft (100).

[0122] [Structure 4]

[0123] According to any one of structures 1 to 3, the solid-phase resistance point bonding device (1) wherein...

[0124] The working cylinder (130) has a metal bushing (132) that forms the inner circumferential surface (135) and slides relative to the piston (140).

[0125] [Structure 5]

[0126] According to any one of structures 1 to 4, the solid-phase resistance point bonding device (1) wherein...

[0127] The solid-state resistance bonding device (1) also includes an insulating sleeve (160) configured to seal the gap between the pressure shaft (100) and the electrode (110).

[0128] The sleeve (160) is slidable relative to the pressure shaft (100) or the electrode (110).

[0129] Embodiments of the present invention have been described, but the embodiments disclosed herein should be considered illustrative in all respects and not restrictive. The scope of the present invention is shown by the technical solutions and is intended to include equivalents and all modifications within the scope of the technical solutions.

Claims

1. A solid-phase resistance spot joining apparatus, wherein the solid-phase resistance spot joining apparatus is provided with: a pressurizing shaft that presses a plurality of joined objects that are overlapped in a manner capable of plastic deformation in an axial direction; an electrode that is disposed around the pressurizing shaft and applies a voltage to the plurality of joined objects; and a drive mechanism that enables the electrode to relatively move in the axial direction with respect to the pressurizing shaft, the drive mechanism includes: a cylinder that is fixed to the pressurizing shaft in a manner surrounding the pressurizing shaft and has an inner peripheral surface that extends in the axial direction; and a piston that is connected to the electrode and is housed in the cylinder and is driven by a pressure of a fluid, the piston divides an inner space of the cylinder into a first chamber and a second chamber, the piston is caused to slide with respect to the inner peripheral surface and is driven in the axial direction by the fluid being alternately introduced into and discharged from the first chamber and the second chamber, whereby the electrode is caused to move in the axial direction together with the piston.

2. The solid-phase resistance spot joining apparatus according to claim 1, wherein the cylinder and the piston each have an insulating portion to insulate the pressurizing shaft from the electrode.

3. The solid-phase resistance spot joining apparatus according to claim 1 or 2, wherein the piston has: a rod portion that extends in the axial direction and one end of the axial direction is connected to the electrode; and a flange portion that extends radially from the other end of the axial direction of the rod portion in a direction orthogonal to the axial direction and abuts against the inner peripheral surface, the first chamber is located on the rod portion side when viewed from the flange portion, the second chamber is located on a side opposite to the rod portion side when viewed from the flange portion, a hole that penetrates in the axial direction is provided in the rod portion and the flange portion, the hole is sealed in a state in which the pressurizing shaft is inserted through the hole, the second chamber is surrounded by the cylinder, the flange portion, and the pressurizing shaft.

4. The solid-phase resistance spot joining apparatus according to claim 1 or 2, wherein the cylinder has a metal-made bushing that constitutes the inner peripheral surface and slides with respect to the piston.

5. The solid-phase resistance spot joining apparatus according to claim 1 or 2, wherein the solid-phase resistance spot joining apparatus is further provided with a sleeve that is disposed in a manner to block a gap between the pressurizing shaft and the electrode and has an insulating property, the sleeve is capable of sliding with respect to the pressurizing shaft or the electrode. ​ ​

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