Solid-phase bonding device

Abstract

To suppress costs for replacing an electrode.SOLUTION: A solid-phase bonding device 1 comprises a first pressing shaft 11 for pressing a first work-piece W10 in a Z1 axial direction, a second pressing shaft 12 for pressing a second work-piece W20 in a Z2 axial direction, and a light source 13 that emits laser light L in the Z1 axial direction. A control device 30 executes a process for making the first pressing shaft 11 press the first work-piece W10 and making the second pressing shaft 12 press the second work-piece W20, and a process for emitting the laser light L to the first work-piece W10, so as to bond the first work-piece W10 to the second work-piece W20 in a solid-phase state.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a solid-state joining apparatus, and more particularly to a solid-state joining apparatus that joins a first workpiece and a second workpiece in a solid-state state. [Background technology]

[0002] For example, Japanese Patent Laid-Open Publication No. 2011-31266 (Patent Document 1) discloses a solid-state welding apparatus that welds two metal plates in a solid state. This solid-state welding apparatus includes an electrode, a pressure mechanism that presses the electrode against the metal plates, and a power source that supplies power to the electrode. This solid-state welding apparatus welds the two metal plates in a solid state by applying pressure between the electrode and the metal plates while the electrode passes current through the metal plates. Hereinafter, this solid-state welding apparatus will also be referred to as an "electrical solid-state welding apparatus." [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2011-31266 Summary of the Invention [Problem to be solved by the invention]

[0004] In the above-mentioned current-passing type solid-state welding apparatus, the electrodes are pressed against the metal plates while current is passed through the metal plates, thereby generating resistance heat between the electrodes and the metal plates. As a result, the electrodes wear out as the solid-state welding apparatus is used, which can cause a problem of electrode replacement costs.

[0005] An object of the present disclosure is to provide a technology that reduces the cost of replacing electrodes. [Means for solving the problem]

[0006] The solid-state joining apparatus of the present disclosure is an apparatus for joining a first workpiece and a second workpiece included in a workpiece in a solid state. The solid-state joining apparatus includes a first pressure shaft for pressing the first workpiece in a first direction, a second pressure shaft for pressing the second workpiece in a second direction opposite to the first direction, a light source for irradiating the first workpiece with a laser beam in the first direction, and a control device for controlling the first pressure shaft and the light source. The control device irradiates the first workpiece with the laser beam while causing the first pressure shaft to press the first workpiece and the second pressure shaft to press the second workpiece, thereby joining the first workpiece and the second workpiece in a solid state.

[0007] According to the present disclosure, solid-state joining can be achieved without using electrodes, thereby preventing the problem of increased electrode replacement costs. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a diagram schematically showing a solid-state joining apparatus according to a first embodiment. [Figure 2] 1A to 1C are diagrams for explaining main steps of solid-state joining. [Figure 3] FIG. 4 is an enlarged view of the shape of the tip of the first pressure shaft. [Figure 4] FIG. 10 is a diagram showing the relationship between a pressed area and an irradiated area in a first workpiece. [Figure 5] FIG. 2 is a functional block diagram of a control device. [Figure 6] FIG. 10 is a diagram illustrating an example of a control table. [Figure 7] 4 is a timing chart when the first control is executed. [Figure 8] 10 is a timing chart when the second control is executed. [Figure 9] 4 is a flowchart showing the flow of main processing of the control device. [Figure 10] FIG. 10 is a diagram showing a configuration example of another solid-state bonding apparatus. [Figure 11] FIG. 10 is a diagram showing a configuration example of another solid-state bonding apparatus. [Figure 12]FIG. 10 is a diagram showing a configuration example of another solid-state bonding apparatus. [Figure 13] FIG. 10 is a diagram illustrating an example of another control table. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. In the drawings, the same or corresponding parts are designated by the same reference numerals, and description thereof will not be repeated.

[0010] <First Embodiment> [Configuration of solid-state bonding equipment] FIG. 1 is a diagram schematically illustrating a solid-state joining apparatus 1 according to a first embodiment. The solid-state joining apparatus 1 joins multiple workpieces that are stacked on top of each other in a solid state. In the example of FIG. 1, the multiple workpieces include a first workpiece W10 and a second workpiece W20. FIG. 1 illustrates an example in which the first workpiece W10 and the second workpiece W20 are joined. The first workpiece W10 and the second workpiece W20 are also collectively referred to as "workpiece W." The workpiece W is held by a holding device (not shown).

[0011] The solid-state joining apparatus 1 irradiates the first workpiece W10 with a laser beam, which will be described later, to heat the irradiated area of ​​the laser beam and form a softened region at the interface of the first workpiece W10. The solid-state joining apparatus 1 then plastically deforms the softened area, thereby joining the first workpiece W10 and the second workpiece W20 in a solid state without melting them. This joining achieves solid-state joining.

[0012] The first workpiece W10 and the second workpiece W20 are, for example, conductors, and more typically, are made of metal such as iron or aluminum. The first workpiece W10 and the second workpiece W20 are, for example, formed in the shape of a flat plate.

[0013] 1, the solid-state bonding apparatus 1 includes a solid-state bonding apparatus 10 and a control device 30. The control device 30 controls each component of the solid-state bonding apparatus 10. The solid-state bonding apparatus 10 includes a first pressure applying shaft 11, a second pressure applying shaft 12, a pressure sensor 40, a light source 13, a housing 14, a first actuator 151, and a second actuator 152. The "pressure applying shaft" may be referred to as a "pressure applying member" or a "pressing member."

[0014] In this embodiment, the thickness direction of the first workpiece W10 and the second workpiece W20 is the Z-axis direction. The plane perpendicular to the Z-axis direction is the XY plane. In the example of FIG. 1, the X-axis of the XY plane is shown. The first workpiece W10 and the second workpiece W20 extend in the XY plane.

[0015] Furthermore, the direction of gravity in the Z-axis direction is referred to as the Z1-axis direction, and the direction opposite to the Z1-axis direction is referred to as the Z2-axis direction. The Z1-axis direction corresponds to the "first direction" in this disclosure. The Z2-axis direction corresponds to the "second direction" in this disclosure. Furthermore, the example in FIG. 1 shows the X1-axis direction and the X2-axis direction.

[0016] First, we will explain the first pressure applying shaft 11 and the second pressure applying shaft 12. The first pressure applying shaft 11 and the second pressure applying shaft 12 have a shape that extends in the Z-axis direction. In this embodiment, the first pressure applying shaft 11 and the second pressure applying shaft 12 have a cylindrical shape.

[0017] A through-hole 50 is formed inside the first pressing shaft 11. That is, the first pressing shaft 11 has a hollow shape. The laser light L from the light source 13 passes through (passes through) the through-hole 50. In this embodiment, the cross-sectional shape of the through-hole 50 in the XY plane is circular. Furthermore, at least a part of the concept of the first pressing shaft 11 described below can be applied to the second pressing shaft 12. For example, the second pressing shaft 12 has the same configuration as the first pressing shaft 11 except that the through-hole 50 is not formed.

[0018] The control device 30 moves the first pressure applying shaft 11 in the Z-axis direction (Z1-axis direction and Z2-axis direction) by driving the first actuator 151. The control device 30 also moves the second pressure applying shaft 12 in the Z-axis direction (Z1-axis direction and Z2-axis direction) by driving the second actuator 152.

[0019] Furthermore, the control device 30 can identify the amount of movement of the first pressure applying shaft 11 (the position of the first pressure applying shaft 11) based on the amount of drive of the first actuator 151. Similarly, the control device 30 can identify the amount of movement of the second pressure applying shaft 12 (the position of the second pressure applying shaft 12) based on the amount of drive of the second actuator 152.

[0020] The first pressure applying shaft 11 presses the first workpiece W10 in the Z1-axis direction (first direction). This causes the first workpiece W10 to undergo plastic deformation. The second pressure applying shaft 12 presses the second workpiece W20 in the Z2-axis direction (second direction). This causes the second workpiece W20 to undergo plastic deformation. In this way, the control device 30 causes the first pressure applying shaft 11 and the second pressure applying shaft 12 to press the first workpiece W10 and the second workpiece W20 from both sides in the Z-axis direction.

[0021] 1 shows a first pressing portion 11a of the first workpiece W10 by the first pressing shaft 11 and a second pressing portion 12a of the first workpiece W10 by the second pressing shaft 12. Furthermore, a protrusion W11 is formed on the surface of the first workpiece W10 opposite to the surface of the first pressing portion 11a. Furthermore, a protrusion W21 is formed on the surface of the second workpiece W20 opposite to the surface of the second pressing portion 12a.

[0022] The pressure sensor 40 detects the load applied to the first workpiece W10 by the first pressure applying shaft 11. The detected load is output to the control device 30. The control device 30 controls the first pressure applying shaft 11 and the second pressure applying shaft 12 based on the load.

[0023] The pressure sensor 40 is disposed, for example, inside the first actuator 151. In this embodiment, a load cell is used as the pressure sensor 40. The pressure sensor 40 may be disposed at a location other than inside the first pressurizing shaft 11 (for example, in the first actuator 151).

[0024] The light source 13 is installed in the housing 14. The light source 13 is also referred to as a "laser irradiation device." The control device 30 transmits an irradiation signal to the light source 13. The irradiation signal is a signal for causing the light source 13 to emit laser light L. Upon receiving the irradiation signal, the light source 13 emits the laser light L in the Z1 axis direction. In this embodiment, due to the communication environment between the control device 30 and the light source 13, a time difference occurs between the timing at which the control device 30 transmits the irradiation signal and the timing at which the light source 13 receives the irradiation signal. This time difference is a value recognized by the control device 30 through experiments or the like, and is hereinafter also referred to as a "predetermined period."

[0025] The laser light L emitted by the light source 13 is irradiated onto the first workpiece W10 through the through hole 50. This laser light L corresponds to the "first laser light" of the present disclosure. The output value of the laser light L is set in advance so as to realize solid-state welding, and is, for example, not less than 400 W and not more than 1200 W. The wavelength of the laser light L is also set in advance so as to realize solid-state welding.

[0026] An input device 61 and a display device 62 are connected to the control device 30. The display device 62 displays various screens under the control of the control device 30. Various information is input to the input device 61 by the user. The input information is output to the control device 30.

[0027] The control device 30 includes an arithmetic unit 31, a memory 32, a storage device 33, and an input / output interface 34. These components are connected via a bus.

[0028] The arithmetic device 31 is a computing entity (computer) that executes predetermined processing. The arithmetic device 31 is configured with a processor such as a CPU (Central Processing Unit), an MPU (Micro-Processing Unit), a TPU (Tensor Processing Unit), or a GPU (Graphics Processing Unit). A processor, which is an example of the arithmetic device 31, has the function of executing predetermined processing by executing a predetermined program. However, part or all of the functions of the arithmetic device 31 may be implemented using a dedicated hardware circuit such as an ASIC (Application Specific Integrated Circuit) or an FPGA (Field-Programmable Gate Array). The arithmetic device 31 may also be referred to as "at least one processor" or "arithmetic circuit."

[0029] The memory 32 includes a storage area (for example, a working area) that stores program code or work memory when the arithmetic unit 31 executes various programs. The memory 32 includes a read-only memory (ROM), a random access memory (RAM), a flash memory, and the like.

[0030] The storage device 33 stores various programs and various data executed by the arithmetic device 31. For example, the storage device 33 stores a control program 330 executed by the arithmetic device 31 to control the first pressure shaft 11 and the second pressure shaft 12. The storage device 33 may be one or more non-transitory computer readable media, or may be one or more computer readable storage media. An example of the storage device 33 is configured by an HDD (Hard Disk Drive) or an SSD (Solid State Drive).

[0031] The input / output interface 34 communicates with external devices (such as the pressure sensor 40, the input device 61, and the display device 62).

[0032] [Solid-state bonding process] 2A and 2B are diagrams illustrating the main steps of solid-state welding. Fig. 2A shows a case where the first pressure applying shaft 11 and the second pressure applying shaft 12 are positioned at their initial positions. Fig. 2B is a diagram illustrating the movement of the first pressure applying shaft 11 and the second pressure applying shaft 12. As shown in Fig. 2B, the control device 30 moves the first pressure applying shaft 11 in the Z1-axis direction and moves the second pressure applying shaft 12 in the Z2-axis direction.

[0033] Fig. 2(C) is a diagram showing pressing by the first pressure shaft 11 and the second pressure shaft 12 and irradiation with laser light L. As shown in Fig. 2(C), the control device 30 causes the first pressure shaft 11 to press the first workpiece W10 and the second pressure shaft 12 to press the second workpiece W20, while irradiating the first workpiece W10 with laser light L. The laser light L mainly heats the first pressed portion 11a.

[0034] 2(D), the control device 30 continues the pressing by the first pressure shaft 11 and the second pressure shaft 12 and the irradiation of the laser light L. This allows the control device 30 to press the first pressure shaft 11 into the first workpiece W10 and press the second pressure shaft 12 into the second workpiece W20. Therefore, the protrusions W11 and W21 are joined together to form a joining interface WA.

[0035] In this way, the solid-state joining apparatus 1 can promote plastic flow of the first workpiece W10 and the second workpiece W20 at the joining interface WA by pressing (applying pressure) and heating the first workpiece W10 and the second workpiece W20. Therefore, the solid-state joining apparatus 1 can achieve solid-state joining at the spots (joining interface WA) of the protrusions W11 of the first workpiece W10 and the protrusions W21 of the second workpiece W20.

[0036] In conventional current-carrying solid-state welding apparatuses, the electrodes are consumed, which can cause a problem of increased electrode replacement costs. In contrast, the solid-state welding apparatus 1 of the present embodiment can achieve solid-state welding without using electrodes, which can prevent the problem of increased electrode replacement costs from occurring.

[0037] Furthermore, in an electric current type solid-state joining apparatus, the electrode may be cylindrical. In this case, it is difficult to completely concentrate the current from the electrode at the center of the joining surface (the pressing point), and a problem may arise in that the area where the current does not concentrate becomes an unjoined area. In contrast, the solid-state joining apparatus 1 of this embodiment directly irradiates the workpiece (first workpiece W10) with laser light L to heat the first workpiece W10 while pressing the first workpiece W10. Therefore, the occurrence of an unjoined area can be suppressed.

[0038] Furthermore, the laser beam L passes through the inside (through-hole 50) of the first pressure shaft 11. Therefore, the solid-state welding apparatus 1 can prevent the laser beam L from coming into contact with anything (such as a user) other than the first workpiece W10.

[0039] [Tip of first pressure shaft 11] Next, we will explain the shape of the tip of the first pressure applying shaft 11. Fig. 3 is an enlarged view of the shape of the tip 60 of the first pressure applying shaft 11. The tip 60 of the first pressure applying shaft 11 is the end portion facing the first workpiece W10.

[0040] The tip 60 of the first pressurizing shaft 11 has a first curved portion 51, a second curved portion 52, a tapered portion 53, and an end face 54. In the example of Fig. 3, a surface 50A of the through-hole 50 is shown. Also, an opening 50B at the tip 60 of the through-hole 50 is shown.

[0041] The end surface 54 is a surface that is pressed against the first workpiece W10. The first curved portion 51 is formed between the end surface 54 and the surface 50A of the through-hole 50. As shown in FIGS. 2(C) and 2(D), the first pressure applying shaft 11 presses the first workpiece W10.

[0042] Furthermore, a corner portion 56 is formed by the body portion 57 and the tapered portion 53 of the first pressure applying shaft 11. The first pressure applying shaft 11 is pressed into the first workpiece W10 up to the corner portion 56 (see FIG. 2(D)). The amount of pressing into the first workpiece W10 is set in advance depending on the thickness of the workpiece W, etc. In this embodiment, the amount of pressing is set to 2.4 mm, for example.

[0043] Hereinafter, the first pressure shaft without the first curved portion 51 will also be referred to as the "first pressure shaft of the first comparative example." In the first pressure shaft of the first comparative example, a corner (corner of the first comparative example) is formed by the end face 54 and the surface 50A. When the first workpiece W10 is made of a soft material (e.g., aluminum or copper), when the first pressure shaft of the first comparative example presses the first workpiece W10, the first workpiece W10 is scraped, and a portion of the first workpiece W10 may adhere to the corner of the first comparative example. When a portion of the first workpiece W10 adheres to the corner, at least a portion of the opening 50B is blocked. Therefore, the amount of laser light L irradiated onto the first workpiece W10 is reduced.

[0044] In contrast, the tip 60 of the first pressure applying shaft 11 of this embodiment has a first curved portion 51. Therefore, unlike the first pressure applying shaft of the first comparative example, it is possible to prevent corners from being formed, which prevents a part of the first workpiece W10 from adhering to the opening 50B. Therefore, it is possible to prevent a decrease in the amount of laser light L irradiated onto the first workpiece W10.

[0045] The tip 60 of the first pressure shaft 11 has a tapered portion 53. Hereinafter, a first pressure shaft without the tapered portion 53 will also be referred to as the "first pressure shaft of the second comparative example." Because the first pressure shaft 11 of this embodiment has the tapered portion 53, the area of ​​the end face 54 of the first pressure shaft 11 of this embodiment can be made smaller than the area of ​​the end face of the first pressure shaft of the second comparative example. Therefore, the pressure applied by the first pressure shaft 11 to the first workpiece W10 can be made greater than that of the first pressure shaft of the second comparative example. Therefore, the solid-state welding apparatus 1 of this embodiment can promote the flow of the material of the first workpiece W10 by the first pressure shaft 11 (see FIG. 2(D)).

[0046] The tip 60 of the first pressure applying shaft 11 has a second curved portion 52 formed between the end face 54 and the tapered portion 53. Hereinafter, a first pressure applying shaft without the second curved portion 52 will also be referred to as the "first pressure applying shaft of the third comparative example." In the first pressure applying shaft of the third comparative example, a corner portion (the corner portion of the third comparative example) is formed by the tapered portion 53 and the end face 54. When the first pressure applying shaft of the third comparative example presses the first workpiece W10, burrs of the first workpiece W10 may adhere to the corner portion of the third comparative example.

[0047] In contrast, the tip 60 of the first pressure applying shaft 11 of the present embodiment has the second curved portion 52. Therefore, unlike the first pressure applying shaft of the third comparative example, it is possible to prevent corners from being formed, thereby suppressing the adhesion of burrs to the first workpiece W10.

[0048] [Pressed area and irradiation area] 4A and 4B are diagrams showing the relationship between the area pressed by the first pressure shaft 11 and the area irradiated with the laser beam L in the first workpiece W10. Fig. 4A is a plan view of the tip 60 of the first pressure shaft 11 when viewed from the Z2 axis direction. Fig. 4B is a diagram showing the area 80 irradiated with the laser beam L and the area 84 pressed by the first pressure shaft 11.

[0049] As shown in FIG. 4(A), when the tip 60 of the first pressure applying shaft 11 is viewed in a plan view from the Z2 axis direction, the opening 50B of the through-hole 50 is surrounded by the area of ​​the end face 54. With this configuration, as shown in FIG. 4(B), the solid-state welding apparatus 1 can irradiate the laser light L to the irradiation area 80 adjacent to the pressing area 84. More specifically, the solid-state welding apparatus 1 can irradiate the laser light L to the irradiation area 80 inside the pressing area 84. Therefore, the first pressure applying shaft 11 can prevent the heat generated by the laser light L irradiated to the irradiation area 80 from leaking out to the outside. Therefore, the solid-state welding apparatus 1 can appropriately heat the irradiation area 80 with the laser light L.

[0050] [Hardness of the first pressure axis] Next, the hardness of the first pressure shaft 11 will be described. As described with reference to FIG. 2(D), the first pressure shaft 11 is pressed into the first workpiece W10, which is metal. Therefore, to prevent damage to the first pressure shaft 11, it is preferable that the first pressure shaft 11 have a certain degree of hardness. The first pressure shaft 11 is made of, for example, a cemented carbide alloy or a tempered material. In this embodiment, the Rockwell hardness A scale of the first pressure shaft 11 is set to 78.6 or more. Furthermore, the Vickers hardness of the first pressure shaft 11 is set to 600 or more. By allowing the first pressure shaft 11 to have such hardness, damage to the first pressure shaft 11 can be prevented even if the first workpiece W10 is made of a hard material to be joined, such as a high-tensile steel plate.

[0051] Furthermore, the first workpiece W10 may be made of a soft material. In such cases, the hardness of the first pressure shaft 11 may be soft, and for example, the Vickers hardness of the first pressure shaft 11 may be any value between 100 and 750. When the first workpiece W10 is made of a soft material, even if the Vickers hardness of the first pressure shaft 11 is any value between 100 and 750, solid-state joining of the first workpiece W10 and the second workpiece W20 can be appropriately achieved.

[0052] Furthermore, in this embodiment, the first pressure shaft 11 is replaceable by the user. If the first workpiece W10 is made of a hard material, a first pressure shaft 11 having a Vickers hardness of 600 or more is attached. If the first workpiece W10 is made of a soft material, a first pressure shaft 11 having a Vickers hardness of any value between 100 and 750 is attached.

[0053] With this configuration, it is possible to prevent at least one of damage to the first pressurizing shaft 11 and the first workpiece W10. The hardness of the second pressurizing shaft 12 may be the same as or different from that of the first pressurizing shaft 11.

[0054] [Controller function block diagram] 5 is a functional block diagram of the control device 30. The control device 30 has an acquisition unit 102, a processing unit 104, a control unit 106, and a storage unit 108. The acquisition unit 102 and the processing unit 104 correspond to the arithmetic device 31. The storage unit 108 corresponds to the memory 32.

[0055] The user can set the mode using the input device 61. Here, the mode will be explained. The amount of heat required for joining in a solid state is determined according to the attributes (characteristics) of the workpiece W (for example, the first workpiece W10). Therefore, some workpieces W require a large amount of heat to be joined, while other workpieces W only require a small amount of heat to be joined. The attributes of the workpieces W include at least one of the type of workpiece W, the thickness of the workpiece W, and the hardness of the workpiece W.

[0056] In consideration of such circumstances, the control device 30 can change the irradiation amount of the laser light L according to the mode set by the user. In this embodiment, the "irradiation amount of the laser light L" is the product of the "output value of the laser light L" and the "irradiation time of the laser light L."

[0057] The control device 30 of this embodiment executes a first control and a second control. The second control is a control in which the irradiation amount of the laser light L is greater than that of the first control. For example, the first control is a control in which the first workpiece W10 is irradiated with a first irradiation amount of laser light. The second control is a control in which the first workpiece W10 is irradiated with a second irradiation amount of laser light. The second irradiation amount is greater than the first irradiation amount. In this way, since the control device 30 can change the irradiation amount of the laser light L, flexible solid-state welding can be achieved depending on the attributes of the workpiece W, and as a result, the quality of the solid-state welding can be improved. In this embodiment, the output value of the laser light L is the same in the first control and the second control, but the irradiation time of the laser light L is different (see FIG. 6).

[0058] The user sets a mode using the input device 61 on a mode setting screen (not shown) displayed on the display device 62. The acquisition unit 102 acquires the set mode. The processing unit 104 temporarily stores a mode flag indicating the set mode in a predetermined storage area (for example, the storage unit 108). The processing unit 104 then references the control table stored in the storage unit 108 to identify a control type corresponding to the set mode flag. The processing unit 104 outputs the identified control type to the control unit 106. The control unit 106 generates a control signal (the above-mentioned irradiation signal) corresponding to the control type identified by the processing unit 104 and outputs it to the light source 13. In this way, the control device 30 executes either the first control or the second control depending on the mode setting by the user. This improves user convenience.

[0059] FIG. 6 is a diagram showing an example of a control table. In the example of FIG. 6, a mode, a control type, and the presence or absence of a preheating period are associated with each other. Here, the preheating period will be explained. As will be described later, for a normal workpiece (for example, a workpiece W that only requires a small amount of heat to be joined), the pressing process and the irradiation of the laser light L are started simultaneously (see FIG. 7). On the other hand, for a workpiece W that requires a large amount of heat to be joined, the irradiation of the laser light L is started a certain period before the start of the pressing process. This certain period corresponds to the preheating period.

[0060] In the example of FIG. 6, the first mode is associated with the first control. The first control is a control that does not include the preheating period. The first control is a control that irradiates the laser light L at a first irradiation amount. The first irradiation amount is an irradiation amount in a first period T1 with a predetermined output (for example, 3 kW in this embodiment).

[0061] The second mode is associated with the second control. The second control is a control that includes the preheating period described above. The second control is a control that irradiates the laser light L with a second irradiation amount. The second irradiation amount is the irradiation amount in the second period T2 with the same predetermined output (3 kW as described above) as the first control. The second period T2 is a period longer than the first period T1. Therefore, the solid-state joining apparatus 1 of this embodiment can change the irradiation amount of the laser light L without having to perform control such as changing the output value of the laser light L in the first control and the second control. Note that the period obtained by subtracting the first period T1 from the second period T2 corresponds to the "preheating period."

[0062] [Timing chart] FIG. 7 is a timing chart when the first control is executed. FIG. 8 is a timing chart when the second control is executed. The horizontal axes of FIGS. 7(A) to 7(C) and 8(A) to 8(C) indicate time. The vertical axes of FIGS. 7(A) and 8(A) indicate the movement distance (stroke) of the first pressure shaft 11 from the initial position. The vertical axes of FIGS. 7(B) and 8(B) indicate the load (value detected by the pressure sensor 40) applied by the first pressure shaft 11 to the workpiece W. The vertical axes of FIGS. 7(C) and 8(C) indicate the output value of the laser light L from the light source 13.

[0063] First, the first control will be described with reference to Fig. 7. At timing t0, the control device 30 starts the solid-state welding process. At timing t0, the control device 30 starts an approach process in which the first pressure shaft 11 and the second pressure shaft 12 are moved closer to the workpiece W by lowering the first pressure shaft 11 and raising the second pressure shaft 12.

[0064] Assume that at timing t1, the control device 30 detects that the first pressure applying shaft 11 has come into contact with the first workpiece W10 (see FIG. 7(B)). For example, the control device 30 acquires a detection value from the pressure sensor 40, and when the detection value reaches a first predetermined value f1 (for example, 1 kN), determines that the first pressure applying shaft 11 has come into contact with the first workpiece W10. In the example of FIG. 7, the movement amount of the first pressure applying shaft 11 and the second pressure applying shaft 12 when contact of the first pressure applying shaft 11 with the first workpiece W10 is detected is d1. Also, at this timing t1, the control device 30 stops the movement of the first pressure applying shaft 11 and the second pressure applying shaft 12, and transmits an irradiation signal (see FIG. 1) to the light source 13.

[0065] At time t2, when the predetermined period has elapsed since time t1, the control device 30 further resumes lowering the first pressure shaft 11 and raising the second pressure shaft 12. As a result, the first workpiece W10 and the second workpiece W20 are pressed.

[0066] Furthermore, this timing t2 is the timing when the light source 13 receives the irradiation signal. Therefore, at timing t2, the light source 13 emits the laser light L. In this way, in the first control, at timing t2, the pressing process by the first pressure shaft 11 and the second pressure shaft 12 and the irradiation process of the laser light L start simultaneously. Note that "simultaneous" in this disclosure includes not only completely simultaneous but also the concept of "substantially simultaneous." "Substantially simultaneous" means, for example, that there is an extremely short time difference (for example, 1 ms).

[0067] The control device 30 continues the pressing process until the amount of pressing reaches a predetermined value (2.4 mm). In the example of FIG. 6, it is assumed that the amount of pressing reaches the predetermined value (2.4 mm) at time t3. The period from time t2 to time t3 is the first period T1 described above. In the example of FIG. 7, the amount of movement at time t3 is d2. The value obtained by subtracting d1 from d2 is the predetermined value (2.4 mm). At time t3, the detected value f2 detected by the pressure sensor 40 is, for example, 40 kN.

[0068] At timing t3, the control device 30 ends the pressing process by the first pressure applying shaft 11 and the second pressure applying shaft 12 and the irradiation process of the laser light L. Then, at timing t3, the control device 30 starts the process of returning the first pressure applying shaft 11 and the second pressure applying shaft 12 to their initial positions. At timing t4, the first pressure applying shaft 11 and the second pressure applying shaft 12 are located at their initial positions.

[0069] Next, the second control will be described with reference to Fig. 8. At timing t2a, which is when the predetermined period has elapsed since timing t1, light source 13 starts irradiating laser light L. Then, while continuing to irradiate laser light L, at subsequent timing t2b, control device 30 starts a pressing process using first pressure applying shaft 11 and second pressure applying shaft 12. The period from timing t2a to timing t2b corresponds to the preheating period. The period from timing t2a to timing t3 corresponds to the second period.

[0070] Then, at timing t31, the control device 30 ends the pressing process by the first pressure applying shaft 11 and the second pressure applying shaft 12 and the irradiation process of the laser light L.

[0071] As described above, in the first control of FIG. 7, the pressing process by the first pressure shaft 11 and the second pressure shaft 12 is started simultaneously with the start of the irradiation process of the laser beam L. On the other hand, in the second control of FIG. 8, the irradiation of the laser beam is started at timing t2a, which is before the preheating period, prior to the start (timing t2b) of the pressing process by the first pressure shaft 11 and the second pressure shaft 12. Therefore, for example, when a large amount of heat is required for solid-state welding of the first workpiece W10 and the second workpiece W20, the solid-state welding apparatus 1 can apply excess heat to the first workpiece W10 with the laser beam L and then perform the pressing process by the first pressure shaft 11 and the second pressure shaft 12. Therefore, the solid-state welding apparatus 1 can apply a large amount of heat to the workpiece W10.

[0072] [flowchart] 9 is a flowchart showing the main processing flow of the control device 30. First, in step S2, the first pressure shaft 11 and the second pressure shaft 12 are moved toward the first workpiece W10 and the second workpiece W20.

[0073] Next, in step S4, the control device 30 determines whether the first pressure applying shaft 11 has come into contact with the first workpiece W10. The control device 30 repeats the processes of steps S2 and S4 until it determines that the first pressure applying shaft 11 has come into contact with the first workpiece W10 (NO in step S4). Then, when the control device 30 determines that the first pressure applying shaft 11 has come into contact with the first workpiece W10 (YES in step S4), the process proceeds to step S6.

[0074] In step S6, the control device 30 stores the contact position as a reference position. Next, in step S8, the control device 30 sets the joining push-in end position (joining position). In the above example, a predetermined value (2.4 mm) is set.

[0075] Next, in step S10, the control device 30 outputs an irradiation signal to the light source 13. Next, in step S12, the control device 30 determines whether the predetermined period has elapsed. The control device 30 repeats the process of step S12 until the predetermined period has elapsed (NO in step S12). Then, when the predetermined period has elapsed (YES in step S12), the process proceeds to step S14.

[0076] In step S14, the control device 30 determines whether the set mode is the first mode. If the set mode is the first mode in step S14 (YES in step S14), the process proceeds to step S18. On the other hand, if the set mode is not the first mode in step S14, that is, the second mode (NO in step S14), the process proceeds to step S16.

[0077] In step S16, control device 30 determines whether the preheating period has elapsed. Control device 30 repeats the process of step S16 until the preheating period has elapsed (NO in step S16). Then, when the preheating period has elapsed (YES in step S16), the process proceeds to step S18.

[0078] In step S18, the control device 30 performs the pressing process (the above-described pressing process) of the first pressure shaft 11 and the second pressure shaft 12 to the joining position set in step S8.

[0079] Next, in step S20, the control device 30 determines whether the first pressure applying shaft 11 and the second pressure applying shaft 12 have reached the joining push-in end position. The control device 30 repeats the processes of step S18 and step S20 until the first pressure applying shaft 11 and the second pressure applying shaft 12 have reached the joining push-in end position (NO in step S20).

[0080] Then, when the first pressure shaft 11 and the second pressure shaft 12 reach the joining push-in end position (YES in step S20), the process proceeds to step S22.

[0081] In step S22, the control device 30 stops the irradiation signal. This stops the output of the laser light L from the light source 13. Next, in step S24, the control device 30 moves the first pressure applying shaft 11 and the second pressure applying shaft 12 toward their initial positions. In step S26, the control device 30 determines whether the first pressure applying shaft 11 and the second pressure applying shaft 12 have reached their initial positions. The control device 30 repeats the processes of step S24 and step S26 until the first pressure applying shaft 11 and the second pressure applying shaft 12 have returned to their initial positions (NO in step S26). If the first pressure applying shaft 11 and the second pressure applying shaft 12 have returned to their initial positions (YES in step S26), the process of FIG. 9 ends.

[0082] The processing of steps S12 to S20 is also collectively referred to as step S100. As shown in step S100 of Fig. 9, the control method of the solid-state joining apparatus 1 includes irradiating the first workpiece W10 with laser light L while causing the first pressure shaft 11 to press the first workpiece W10 and the second pressure shaft 12 to press the second workpiece W20, thereby joining the first workpiece W10 and the second workpiece W20 in a solid state.

[0083] <Embodiment 2> In the second embodiment, another example of the solid-state bonding apparatus 10 will be described. Fig. 10 is a diagram showing a configuration example of the solid-state bonding apparatus 10A. In the example of Fig. 10, the light source 13, the housing 14, the through-hole 50, and the laser light L are shown as a first light source 131, a first housing 141, a first through-hole 501, and a first laser light L1, respectively.

[0084] The solid-state welding apparatus 10A further includes a second light source 132 and a second housing 142. A second through-hole 502 is formed inside the second pressure shaft 12. The second through-hole 502 extends in the Z2-axis direction. The second light source 132 irradiates a second laser beam L2. The second laser beam L2 passes through the second through-hole 502 and is irradiated onto the second pressing portion 12a of the second workpiece W20.

[0085] In the flowchart of the process of the solid-state bonding apparatus 1 in which the solid-state bonding equipment 10A is adopted, an irradiation signal is output in step S10, causing the first light source 131 to output the first laser light L1 and the second light source 132 to output the second laser light L2. In addition, the output of the irradiation signal is stopped in step S22, causing the output of the first laser light L1 and the second laser light L2 to stop.

[0086] The solid-state welding apparatus 1 equipped with such solid-state welding equipment 10A can make the irradiation amount of the first laser beam L1 and the irradiation amount of the second laser beam L2 the same or different depending on the attributes of the first workpiece W10 and the second workpiece W20. Therefore, even if the attributes of the first workpiece W10 and the second workpiece W20 are different, the solid-state welding apparatus 1 can improve the quality of the solid-state welding of the first workpiece W10 and the second workpiece W20.

[0087] 11 is a diagram showing a configuration example of a solid-state welding apparatus 10B. In the solid-state welding apparatus 10B, the second pressurizing shaft 12 of the solid-state welding apparatus 10A is configured to be fixed to the stage 160. Even with this configuration, the solid-state welding apparatus 1 can realize solid-state welding of the first workpiece W10 and the second workpiece W20.

[0088] 12 is a diagram showing a configuration example of a solid-state bonding apparatus 10C. The solid-state bonding apparatus 10C is an apparatus that does not include the second light source 132. Even with this configuration, the same effects as those of the solid-state bonding apparatus 1 of the first embodiment can be achieved.

[0089] <Third Embodiment> In the first embodiment, the solid-state welding apparatus 1 that executes either the first control or the second control in accordance with the user's setting (mode) has been described (see FIG. 6). In the third embodiment, the solid-state welding apparatus 1 executes either the first control or the second control in accordance with the attributes of the workpieces W.

[0090] FIG. 13 is an example of a control table used in this embodiment. The control table in FIG. 13 is a table modified from the control table in FIG. 6. In the example in FIG. 13, the work attribute, the control type, and the irradiation amount (irradiation period) are associated with each other. In the example in FIG. 13, to simplify the explanation, it is assumed that the work attribute is divided into a first attribute and a second attribute. In the example in FIG. 13, the first attribute is associated with the first control. The second attribute is associated with the second control.

[0091] In the third embodiment, as shown in parentheses in FIG. 5, the user inputs attributes of the workpiece W from the input device 61. The processing unit 104 determines whether the attribute input by the user belongs to the first attribute or the second attribute. If the attribute is the first attribute, the control unit 106 controls the light source 13 to perform the first control. If the attribute is the second attribute, the control unit 106 controls the light source 13 to perform the second control.

[0092] According to this configuration, the control device 30 can change the irradiation amount of the laser light in accordance with the attributes of the workpiece W. Furthermore, the solid-state joining apparatus 1 accepts input of the attributes of the workpiece from the user. Therefore, the irradiation amount of the laser light L can be changed by the user inputting the attributes. This improves user convenience.

[0093] In the present embodiment, a configuration has been described in which the attributes of the workpiece W are input by a user. However, the solid-state welding apparatus 1 may be configured to automatically identify the attributes of the workpiece W. For example, the solid-state welding apparatus 1 may be configured to include a camera that captures an image of the workpiece W. Then, the solid-state welding apparatus 1 may be configured to analyze the image of the workpiece W captured by the camera to identify the attributes of the workpiece W.

[0094] Also, in the control tables of Fig. 6 and Fig. 13, a configuration has been described in which the number of control types N (N is an integer) is "2". However, the number of control types N may be 3 or more. In such a configuration, in Fig. 6, the same number of modes and control types as N are defined. In Fig. 13, the same number of attributes and control types as N are defined. Then, the irradiation period (irradiation amount) is defined so as to be different for each of the N control types.

[0095] Furthermore, in the third embodiment, the control device 30 may not use the control table of Fig. 13. In this case, the control device 30 may use, for example, AI (Artificial Intelligence) to determine the control type based on the attributes of the workpiece W. For example, the control device 30 determines the control type by inputting the attributes of the workpiece W into a trained model.

[0096] [Other embodiments] (1) In the above embodiment, a configuration has been described in which the through hole 50 is formed in the first pressure applying shaft 11, and the laser light L from the light source 13 passes through the through hole 50. However, the through hole 50 does not have to be formed in the first pressure applying shaft 11. In this case, a configuration is adopted in which the light source 13 irradiates the laser light L onto the first pressing portion 11a from the side of the first pressure applying shaft 11. Similarly, a configuration is adopted in which the second light source 132 irradiates the second laser light L2 onto the second pressing portion 12a from the side of the second pressure applying shaft 12.

[0097] (2) In the examples of FIGS. 7 and 8, the control device 30 is configured to control the first pressure applying shaft 11, the second pressure applying shaft 12, the light source 13, etc. based on the detection value of the pressure sensor 40. However, the control device 30 may be configured to control the first pressure applying shaft 11, the second pressure applying shaft 12, the light source 13, etc. based on other parameters. The other parameters may be, for example, the amount of movement of the first pressure applying shaft 11 and the second pressure applying shaft 12. The other parameters may also be time.

[0098] (3) In the above embodiment, an example has been described in which the irradiation period of the laser light L is synchronized with the pressing period of the workpiece W. However, as long as solid-state joining of the first workpiece W10 and the second workpiece W20 is achieved, the irradiation period and the pressing period do not need to be synchronized.

[0099] <Additional Notes> (1-1) A solid-state welding apparatus according to the present disclosure is an apparatus for solid-state welding a first workpiece and a second workpiece. The solid-state welding apparatus includes a first pressure shaft for pressing the first workpiece in a first direction, a second pressure shaft for pressing the second workpiece in a second direction opposite to the first direction, and a first light source for irradiating a first laser beam in the first direction. A first through-hole extending along the first direction is formed in the first pressure shaft. The first laser beam is irradiated through the first through-hole.

[0100] In conventional current-carrying solid-state welding apparatuses, the electrodes are subject to wear, which can lead to a problem of increased electrode replacement costs. In contrast, the solid-state welding apparatus of the present disclosure can achieve solid-state welding without using electrodes, which can prevent the problem of increased electrode replacement costs from occurring.

[0101] (1-2) In the solid-state welding apparatus according to (1-1), the tip of the first pressure shaft has a first curved portion formed between an end face of the tip and a surface of the first through hole.

[0102] According to this configuration, when the first pressure shaft presses the first workpiece, it is possible to prevent fragments of the first workpiece from adhering to the opening of the through hole.

[0103] (1-3) In the solid-state welding apparatus according to (1-1), the tip of the first pressure shaft has a tapered portion that tapers toward the tip.

[0104] With this configuration, the pressure shaft can be pressed into the first workpiece more appropriately than a pressure shaft whose tip does not have a tapered portion.

[0105] (1-4) In the solid-state welding apparatus according to (1-3), the tip of the first pressure shaft has a second curved portion formed between the end face and the tapered portion.

[0106] With this configuration, burrs on the first workpiece can be removed. (1-5) In the solid-state welding apparatus according to any one of (1-2) to (1-4), when the tip of the first pressure shaft is viewed in a plan view from the second direction, the opening of the first through hole is surrounded by the end face.

[0107] According to this configuration, the laser light can be irradiated onto the area inside the area that is pressed against the first workpiece, and therefore, heat generated by the laser light can be prevented from leaking to the outside.

[0108] (1-6) In the solid-state welding apparatus according to any one of (1-1) to (1-5), the first pressure shaft has a Rockwell hardness A scale value of 78.6 or more.

[0109] With this configuration, even if the first workpiece is a hard material to be joined, such as a high-tensile steel plate, damage to the first pressure shaft can be suppressed.

[0110] (1-7) A solid-state welding apparatus according to any one of (1-1) to (1-5), wherein the solid-state welding apparatus is replaceable with a first pressure shaft having a Vickers hardness of 600 or more and a first pressure shaft having a Vickers hardness of 100 or more but less than 750.

[0111] With this configuration, for example, if the first workpiece is hard, by attaching a first pressure shaft with a Vickers hardness of 600 or more, it is possible to prevent the first pressure shaft from being damaged. On the other hand, if the first workpiece is made of a soft material, even if the Vickers hardness of the first pressure shaft is 100 or more and less than 750, it is possible to properly achieve solid-state welding of the first workpiece and the second workpiece.

[0112] (1-8) The solid-state welding apparatus according to any one of (1-1) to (1-7), wherein the second pressure shaft has a second through-hole formed along the second direction. The solid-state welding apparatus also includes a second light source that irradiates a second laser beam in the second direction. The second laser beam is irradiated via the second through-hole.

[0113] According to this configuration, the output of the first laser light corresponding to the first workpiece and the output of the second laser light corresponding to the second workpiece can be separated to realize solid-state joining of the first workpiece and the second workpiece.

[0114] (2-1) A solid-state joining apparatus according to the present disclosure is an apparatus for joining a first workpiece and a second workpiece included in a workpiece in a solid state. The solid-state joining apparatus includes a first pressure shaft for pressing the first workpiece in a first direction, a second pressure shaft for pressing the second workpiece in a second direction opposite the first direction, a light source for irradiating the first workpiece with a laser beam in the first direction, and a control device for controlling the first pressure shaft and the light source. The control device joins the first workpiece and the second workpiece in a solid state by executing a process for causing the first pressure shaft to press the first workpiece and the second pressure shaft to press the second workpiece, and a process for irradiating the first workpiece with the laser beam.

[0115] In a conventional current-carrying type solid-state welding apparatus, the electrodes are consumed, which can cause a problem of increased electrode replacement costs. In contrast, the solid-state welding apparatus of the present embodiment can achieve solid-state welding without using electrodes, which can prevent the problem of increased electrode replacement costs from occurring.

[0116] (2-2) A solid-state joining apparatus as described in (2-1), wherein the control device executes a first control for irradiating a first workpiece with laser light and a second control for irradiating the first workpiece with laser light having a larger irradiation amount than that of the first control.

[0117] According to this configuration, the amount of laser light irradiation can be changed, so that flexible solid-state welding can be achieved according to the attributes of the workpieces.

[0118] (2-3) In the solid-state joining apparatus according to (2-2), the control device executes either the first control or the second control in accordance with a setting by a user.

[0119] This configuration can improve user convenience. (2-4) The solid-state welding apparatus according to (2-2), wherein the solid-state welding apparatus executes either the first control or the second control in accordance with the attributes of the workpieces.

[0120] With this configuration, the amount of laser light irradiation can be changed depending on the attributes of the workpiece. (2-5) The solid-state welding apparatus according to (2-4), further comprising an input device that receives input of attributes of the workpieces from a user.

[0121] According to this configuration, the user can change the irradiation amount of the laser light by inputting the attribute.

[0122] (2-6) A solid-state joining apparatus according to any one of (2-2) to (2-5), wherein the output value of the laser light in the first control and the output value of the laser light in the second control are the same, and the irradiation time of the laser light in the second control is longer than the irradiation time of the laser light in the first control.

[0123] According to this configuration, the laser irradiation amount can be changed while keeping the laser output the same in the first control and the second control.

[0124] (2-7) A solid-state joining apparatus as described in (2-6), wherein the control device, when executing the first control, starts irradiating laser light from the light source and starts pressing by the first pressure shaft and the second pressure shaft, and, when executing the second control, starts irradiating laser light before pressing by the first pressure shaft and the second pressure shaft starts.

[0125] According to this configuration, the first workpiece can be preheated by the laser light and then pressed.

[0126] (2-8) In the control method for a solid-state joining apparatus of the present disclosure, the solid-state joining apparatus is an apparatus for joining a first workpiece and a second workpiece included in a workpiece in a solid state. The solid-state joining apparatus includes a first pressure shaft for pressing the first workpiece in a first direction, a second pressure shaft for pressing the second workpiece in a second direction opposite to the first direction, and a light source for irradiating the first workpiece with a laser beam in the first direction. The control method includes joining the first workpiece and the second workpiece in a solid state by irradiating the first workpiece with a laser beam while causing the first pressure shaft to press the first workpiece and the second pressure shaft to press the second workpiece.

[0127] The embodiments disclosed herein should be considered to be illustrative in all respects and not restrictive. The scope of the present disclosure is defined by the claims, not by the description of the above embodiments, and is intended to include all modifications within the meaning and scope of the claims. [Explanation of symbols]

[0128] 1 Solid-state bonding apparatus, 10, 10A, 10B, 10C Solid-state bonding equipment, 11 First pressure shaft, 11a First pressure portion, 12 Second pressure shaft, 12a Second pressure portion, 13 Light source, 14 Housing, 30 Control device, 31 Arithmetic device, 32 Memory, 33 Storage device, 34 Input / output interface, 40 Pressure sensor, 50 Through hole, 50A Surface, 50B Opening, 51 First curved portion, 52 Second curved portion, 53 Tapered portion, 54 End surface, 56 Corner portion, 57 Body portion, 60 Tip, 61 Input device, 62 Display device, 80 Irradiation area, 84 Pressing area, 102 Acquisition unit, 104 Processing unit, 106 Control unit, 108 Memory unit, 131 First light source, 132 Second light source, 141 First housing, 142 Second housing, 151 First actuator, 152 second actuator, 160 stage, 330 control program, 501 first through-hole, 502 second through-hole, L laser light, L1 first laser light, L2 second laser light.

Claims

1. A solid-state joining apparatus for joining a first workpiece and a second workpiece included in a workpiece in a solid state, a first pressure shaft for pressing the first workpiece in a first direction; a second pressure shaft for pressing the second workpiece in a second direction opposite to the first direction; a light source that irradiates the first workpiece with laser light in the first direction; a control device that controls the first pressure shaft and the light source, The control device performs a process of pressing the first workpiece against the first pressure shaft and pressing the second workpiece against the second pressure shaft, and a process of irradiating the first workpiece with the laser light, thereby joining the first workpiece and the second workpiece in a solid state.

2. The control device a first control for irradiating the first workpiece with the laser light; 2. The solid-state joining apparatus according to claim 1, wherein a second control is performed in which the first workpiece is irradiated with the laser light at an irradiation amount greater than that of the first control.

3. The solid-state joining apparatus according to claim 2 , wherein the control device executes either the first control or the second control in accordance with a setting by a user.

4. The solid-state welding apparatus according to claim 2 , wherein the solid-state welding apparatus executes either the first control or the second control depending on an attribute of the workpiece.

5. The solid-state welding apparatus according to claim 4 , further comprising an input device that accepts input of attributes of the workpiece from a user.

6. an output value of the laser beam in the first control and an output value of the laser beam in the second control are the same; 6. The solid-state joining apparatus according to claim 2, wherein the irradiation time of the laser light in the second control is longer than the irradiation time of the laser light in the first control.

7. The control device when the first control is executed, the light source starts irradiating the laser light, and the first pressure applying shaft and the second pressure applying shaft start pressing the laser light; The solid-state joining apparatus according to claim 6 , wherein, when the second control is executed, the irradiation of the laser light is started before the pressing by the first pressure shaft and the second pressure shaft is started.

8. A control method for a solid-state joining apparatus for joining a first workpiece and a second workpiece included in a workpiece in a solid-state state, comprising: The solid-state bonding apparatus comprises: a first pressure shaft for pressing the first workpiece in a first direction; a second pressure shaft for pressing the second workpiece in a second direction opposite to the first direction; a light source that irradiates the first workpiece with laser light in the first direction; The control method for a solid-state joining apparatus includes: pressing the first workpiece against the first pressure shaft and pressing the second workpiece against the second pressure shaft, while irradiating the first workpiece with the laser light, thereby joining the first workpiece and the second workpiece in a solid-state state.

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