Friction stir point welding apparatus and its operation method

Abstract

To suppress adhesion of a powder piece of a junction object member to a tool without complicating a structure.SOLUTION: A friction stir spot joining device M includes a tool 1 for friction stir spot joining including a pin 11, a shoulder 12 having a hollow part to which the pin 11 is inserted, and an oil agent 7 interposed in an interlayer 1A between an outer peripheral surface of the pin 11 and an inner peripheral surface of the shoulder 12, and a controller C of the tool 1. The controller C executes first operation control of relatively moving the pin 11 to the shoulder 12 in a state where the oil agent 7 is held in the interlayer 1A, and second operation control of relatively moving the pin 11 to the shoulder 12 so as to discharge the oil agent 7 containing a powder piece 8 to the outside through a tip opening 12A of the hollow part from the interlayer 1A.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present disclosure relates to a friction stir spot welding apparatus having a pin and a shoulder, and an operation method thereof.

Background Art

[0002] As a method of joining two or more members made of a metal member, a fiber reinforced thermoplastic resin member, etc. by overlapping them, joining using friction stir is known. For friction stir joining, a tool for friction stir spot welding having a pin and a shoulder having a hollow portion for accommodating the pin may be used. For example, in the shoulder first process, while the shoulder is projected and press-fitted into the overlapping portion of the members, the pin is retracted to accommodate the material overflowing due to the press-fitting.

[0003] Since a part of the tool is press-fitted into the joining target member, powder of the joining target member may be incorporated into the tool. As the number of joining points increases, the amount of incorporated powder also increases, and finally, it adheres to the pin surface and hinders the operation of the tool. Patent Document 1 discloses a friction stir spot welding apparatus that performs a cleaning operation of protruding a pin processed into a special shape relative to the shoulder or bringing a brush into contact with the pin in order to remove the adherents on the pin.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] The apparatus of Patent Document 1 requires a shape modification for cleaning the tool and a separately installed cleaning tool. Therefore, the structure of the friction stir spot welding apparatus is complicated.

[0006] The present disclosure aims to provide a friction stir point welding apparatus that can suppress the adhesion of powder fragments of the members to be joined to the tool without complicating the structure. [Means for solving the problem]

[0007] A friction stir point bonding apparatus according to one aspect of the present disclosure comprises a tool for friction stir point bonding, which includes a pin, a shoulder having a hollow portion through which the pin is inserted, and an oil interposed between layers of the outer circumferential surface of the pin and the inner circumferential surface of the shoulder, and a control unit for the tool, wherein the control unit performs a first operation control to move the pin relative to the shoulder while the oil is held between the layers, and a second operation control to move the pin relative to the shoulder such that the oil is discharged to the outside through the tip opening of the hollow portion from between the layers.

[0008] A method for operating a friction stir point welding apparatus according to another aspect of the present disclosure is a method for operating a friction stir point welding apparatus comprising a pin, a shoulder having a hollow portion through which the pin is inserted, and an oil interposed between the outer circumferential surface of the pin and the inner circumferential surface of the shoulder, wherein during friction stir welding, the pin is moved relative to the shoulder while the oil is held between the layers, and when the oil is to be discharged from between the layers, the pin is moved relative to the shoulder so that the oil is discharged to the outside through the tip opening of the hollow portion from between the layers. [Effects of the Invention]

[0009] According to this disclosure, it is possible to provide a friction stir point welding apparatus that can suppress the adhesion of powder fragments of the members to be joined to the tool without complicating the structure. [Brief explanation of the drawing]

[0010] [Figure 1] Figure 1 is a schematic diagram showing the configuration of a friction stir point welding apparatus according to an embodiment of the present disclosure. [Figure 2] Figure 2 shows an example of a joining method using a friction stir point joining apparatus. [Figure 3] Figure 3 is an exploded cross-sectional view of a tool according to the first embodiment, which is included in a friction stir point welding apparatus. [Figure 4] Figure 4 is a cross-sectional view showing the state of the tool in the welding stage where friction stir welding is performed. [Figure 5] Figure 5 is a cross-sectional view showing the state of the tool during the discharge stage, where the lubricant is discharged from the tool. [Figure 6] Figure 6 is a cross-sectional view showing the state of the tool during the lubrication stage, where lubricant is supplied to the tool. [Figure 7] Figures 7(A) and (B) are cross-sectional views showing the lubrication operation of the tool according to the second embodiment. [Figure 8] Figure 8(A) is a cross-sectional view showing the joining stage using the tool according to the second embodiment, and Figures 8(B) and (C) show the oil discharge stage, respectively. [Modes for carrying out the invention]

[0011] The embodiments of this disclosure will be described in detail below with reference to the drawings. The friction stir point joining apparatus according to this disclosure can be applied to the manufacture of various joints formed by overlapping and point joining two or more structural materials such as metal or resin plates, frames, exterior materials, or columnar materials. The joints manufactured can be used as components of structures such as aircraft, railway vehicles, or automobiles.

[0012] [Configuration of friction stir point bonding device] Figure 1 is a schematic diagram showing the configuration of a friction stir point welding apparatus M according to one embodiment of the present disclosure. The friction stir point welding apparatus M includes a tool 1 for friction stir point welding, a tool drive unit 2 for rotating and lifting the tool 1, a blower 25 for supplying airflow to the tool 1, a lubrication device 26 for supplying lubricant to the tool 1, and a controller C (tool control unit) for controlling the operation of each part of the friction stir point welding apparatus M. Note that Figure 1 is marked with "up" and "down" directions, but this is for the convenience of explanation and is not intended to limit the actual direction of use of the tool 1.

[0013] Tool 1 is supported by various tool fixing parts. For example, the tool fixing part is the tip of an articulated robot. A backup 15 is positioned opposite the lower end surface of tool 1. At least two members to be joined are positioned between tool 1 and backup 15. Figure 1 shows an example in which an overlapping portion 30, in which a part of a first member 31 made of a flat plate and a part of a second member 32 also made of a flat plate overlap in the vertical direction, is positioned between tool 1 and backup 15.

[0014] Tool 1 includes a pin 11, a shoulder 12, a clamp 13, and a spring 14. The pin 11 is a cylindrical member, and its axis extends in the vertical direction. The pin 11 is rotatable around its axis R and can move up and down along the axis R. When using Tool 1, the axis R and the point contact position W at the overlapping portion 30 are aligned.

[0015] The shoulder 12 is a cylindrical member having a hollow portion through which the pin 11 is inserted. The axis of the shoulder 12 is coaxial with the axis of the pin 11, i.e., the rotation axis R. The shoulder 12 is rotatable around the rotation axis R and can move up and down along the rotation axis R. As will be described in detail later, in this embodiment, an oil is interposed between the outer surface of the pin 11 and the inner surface of the shoulder 12 to enhance lubricity and suppress the adhesion of deposits.

[0016] Tool 1 of this embodiment is a double-acting tool in which the pin 11 and shoulder 12 move independently in the axial direction. That is, the shoulder 12 and the pin 11 inserted into the hollow portion can both rotate around the axis of rotation R and move relative to each other in the direction of rotation axis R. Specifically, the pin 11 and shoulder 12 can not only move up and down simultaneously along rotation axis R, but can also move independently, with one moving down and the other moving up.

[0017] The clamp 13 is a member formed in a cylindrical shape and has a hollow portion into which the shoulder 12 is inserted. The axis of the clamp 13 is also coaxial with the rotation axis R. The clamp 13 does not rotate around the axis but moves up and down, that is, advances and retreats, along the rotation axis R. The clamp 13 serves to surround the outer peripheries of the pin 11 or the shoulder 12 when friction stirring is performed. By the enclosure of the clamp 13, the friction stir material is not scattered, and the friction stir point joining portion can be finished smoothly.

[0018] The spring 14 is attached to the upper end side of the clamp 13 and biases the clamp 13 downward toward the overlapping portion 30. The clamp 13 is attached to the tool fixing portion via the spring 14. The backup 15 has a plane that abuts against the lower surface side of the overlapping portion 30 of the joining target. The backup 15 is a backing member that supports the overlapping portion 30 when the pin 11 or the shoulder 12 is press-fitted into the overlapping portion 30. The clamp 13 biased by the spring 14 presses the overlapping portion 30 against the backup 15.

[0019] The tool drive unit 2 includes a rotation drive unit 21, a pin drive unit 22, a shoulder drive unit 23, and a clamp drive unit 24. The rotation drive unit 21 includes a motor, drive gears, etc., and rotationally drives the pin 11 and the shoulder 12 around the rotation axis R. The pin drive unit 22 is a mechanism that moves the pin 11 forward and backward along the rotation axis R. The pin drive unit 22 drives the pin 11 so as to perform press-fitting of the pin 11 into the overlapping portion 30 and retraction from the overlapping portion 30. The shoulder drive unit 23 is a mechanism that moves the shoulder 12 forward and backward along the rotation axis R, and causes the shoulder 12 to perform press-fitting into and retraction from the overlapping portion 30. The clamp drive unit 24 is a mechanism that moves the clamp 13 forward and backward along the rotation axis R. The clamp drive unit 24 moves the clamp 13 toward the overlapping portion 30 and presses the overlapping portion 30 against the backup 15. At this time, the biasing force of the spring 14 acts.

[0020] The blower 25 generates an airflow and supplies it between the layers of the pin 11 and the shoulder 12. The blower 25 is preferably a device capable of generating a high-pressure airflow; for example, an axial flow blower equipped with a multi-blade fan or a turbo fan can be used.

[0021] The lubrication device 26 supplies lubricant between the pin 11 and the shoulder 12. The lubrication device 26 includes, for example, a tank for storing the lubricant and a pump for pumping the lubricant. As the lubricant, a liquid or grease-like lubricant that has the effect of preventing metal adhesion can be used. For example, mineral oil or synthetic oil mainly composed of lubricating oil base oil or petroleum hydrocarbons can be used as the lubricant. Alternatively, mineral oil or synthetic oil to which molybdenum, graphite, solid paraffin, or metal powder has been added as a solid lubricant may also be used as the lubricant.

[0022] Controller C consists of a microcomputer and the like, and controls the operation of the tool drive unit 2, the blower 25, and the lubrication device 26 by executing a predetermined control program. Specifically, Controller C controls the rotation drive unit 21 to cause the pin 11 and shoulder 12 to perform the required rotational movement. Controller C also controls the pin drive unit 22, the shoulder drive unit 23, and the clamp drive unit 24 to cause the pin 11, shoulder 12, and clamp 13 to perform the required forward and backward movement. Furthermore, Controller C controls the operation of the blower 25 and the lubrication device 26 to control the blowing and lubrication operations on the tool 1.

[0023] [How to use the tool] Next, the method of using Tool 1 as illustrated in this embodiment will be described. Broadly speaking, there are two methods of using the friction stir point welding apparatus M: a pin-first process in which the pin 11 of Tool 1 is pressed into the overlapping portion of the joining members first, and a shoulder-first process in which the shoulder 12 is pressed into the overlapping portion of the joining members first. In this embodiment, the shoulder-first process is employed.

[0024] Figure 2 shows processes P11 to P14 of the friction stir point joining method using the shoulder-first process. Processes P11 to P14 simply illustrate the situation in which the overlapping portion 30 of the first member 31 and the second member 32 are friction stir point joined. Process P11 shows the preheating process of the overlapping portion 30. With the lower end of the tool 1 in contact with the surface of the first member 31, the controller C rotates the pin 11 and the shoulder 12 around the axis at a predetermined number of rotations.

[0025] Process P12 represents the press-fitting process of the shoulder 12. In this press-fitting process, the controller C lowers the shoulder 12 and presses it into the overlap 30, while simultaneously retracting the pin 11 upward. This action stirs the material in the press-fitting area of ​​the shoulder 12. In addition, the overflow material OF that spills out from the overlap 30 due to the press-fitting is released into the hollow space of the shoulder 12 created by the retraction of the pin 11 (see arrow a1). Thus, in this embodiment, the pin 11 is moved upward relative to the shoulder 12 during friction stir welding.

[0026] Process P13 represents the backfilling process for the overflow material OF. During the backfilling process, the controller C raises and retracts the shoulder 12 while lowering the pin 11. As the pin 11 is lowered, the overflow material OF that escaped into the hollow space is backfilled into the press-fit area of ​​the shoulder 12, as indicated by arrow a2. Process P14 represents the leveling process. The pin 11 and the lower end surfaces of the shoulder 12 are returned to the height of the surface of the first member 31, and both are rotated to smooth the point joint portion. Through the above processes, the agitated joint portion 4 is formed.

[0027] The friction stir point welding apparatus M of this embodiment is suitable for joining metal materials together. As an example, the upper plate of the overlapping portion 30, i.e., the first member 31 on the side into which the tool 1 is pressed, is made of aluminum alloy, and the lower plate, the second member 32, is made of high-tensile steel. When friction stir welding is performed on such an overlapping portion 30 of metal materials by pressing the tool 1 into the upper plate, metal powder fragments generated during pressing, in the above example, aluminum powder fragments, inevitably become trapped inside the tool 1. The trapping of powder fragments increases the operating load on the tool 1, which can lead to malfunction of the tool 1.

[0028] The above problem can be mitigated by interposing a lubricating oil between the layers of pin 11 and shoulder 12. In other words, the interposition of the oil suppresses the entry of powder fragments, such as the aluminum powder fragments shown above, into the interlayer due to the press-fitting of tool 1. Furthermore, the lubricating effect of the oil also suppresses the adhesion of powder fragments to the outer surface of pin 11. However, it has been found that when the number of joining points by tool 1 exceeds tens of thousands, powder fragments begin to accumulate in the oil between the layers. As the accumulation of powder fragments progresses, relatively large aggregated fragments are formed, and these aggregated fragments are pressed and adhered to the outer surface of pin 11, which can lead to malfunction of tool 1. The friction stir point joining apparatus M of this embodiment has the feature of being able to suppress the adhesion of the above powder fragments. The configuration that realizes this feature will be described below.

[0029] [Tool Class 1 Embodiment] Tool 1 of this embodiment performs two operations: first operation control, which involves friction bonding by moving the pin 11 relative to the shoulder 12 while holding the oil between the layers of the pin 11 and the shoulder 12; and second operation control, which involves forcibly discharging the oil that may have become contaminated due to the inclusion of powder fragments from the layer gap. The pin 11 and shoulder 12 have a shape that enables these operations.

[0030] <Specific shape of the tool> Figure 3 is a cross-sectional view of the pin 11 and shoulder 12 of the tool 1 according to the first embodiment, disassembled. The pin 11 is a cylindrical body whose diameter gradually decreases towards the lower end 11T, and has a small-diameter tip portion 51, a medium-diameter portion 52, and a large-diameter portion 53. The small-diameter tip portion 51 is the smallest outer diameter portion that forms the tip of the pin 11, and its tip surface is the lower end 11T of the pin 11. The medium-diameter portion 52 is located approximately in the middle of the axial direction of the pin 11 and is a cylindrical portion with a larger diameter than the small-diameter tip portion 51. The upper end of the small-diameter tip portion 51 and the lower end of the medium-diameter portion 52 are connected by a first tapered portion 54. Note that the regions corresponding to the small-diameter tip portion 51 and the medium-diameter portion 52 may be made of the same diameter, and the first tapered portion 54 may be omitted.

[0031] The large-diameter portion 53 is formed in the upper part of the pin 11 and is a cylindrical portion with a larger diameter than the medium-diameter portion 52. The upper end of the medium-diameter portion 52 and the lower end of the large-diameter portion 53 are connected by a second tapered portion 55. A flange portion 56, which is even larger in diameter than the large-diameter portion 53, is attached to the upper end of the large-diameter portion 53, and an engaging portion 57 is attached to the upper end of the flange portion 56. A pin base 58 having a hollow portion for fitting is fitted into the engaging portion 57. The pin base 58 is part of a gun attached to the tip of a robot arm, for example. The lower end surface of the pin base 58 is in contact with the flange portion 56. An annular projection 59 (air seal portion) projecting radially outward is integrally formed on the side surface of the pin base 58.

[0032] The shoulder 12 consists of a cylindrical body capable of housing the pin 11 and has a tip 61, an intermediate section 62, a base section 63, and an inlet 64. The tip 61 and the intermediate section 62 have the same outer diameter, while the base section 63 has a larger diameter. The lower end of the base section 63 and the upper end of the intermediate section 62 are connected by a tapered section 63T.

[0033] The tip portion 61 is the part that forms the tip of the shoulder 12, and its tip surface is the lower end portion 12T of the shoulder 12. Inside the tip portion 61, a cylindrical tip hollow portion 12B is formed, which has an inner diameter slightly larger than the outer diameter of the tip small diameter portion 51 of the pin 11. The intermediate portion 62 is the part that is connected to the upper part of the tip portion 61, and inside it is a cylindrical intermediate hollow portion 12H that is connected to the tip hollow portion 12B. The inner diameter of the intermediate hollow portion 12H is larger than the outer diameter of the medium diameter portion 52 of the pin 11 by a predetermined diameter difference gap, and is slightly larger than the large diameter portion 53. The base portion 63 is a cylindrical portion that is connected to the upper part of the intermediate portion 62 via a tapered portion 63T. The base portion 63 has a plurality of inlet openings 64 that penetrate radially through the wall of the base portion 63.

[0034] The upper end of the base portion 63 is fitted into a cylindrical shoulder base 65. The shoulder base 65 is also, for example, part of the gun. The shoulder base 65 and the base portion 63 partition a supply chamber 67, which is a sealed space when airflow is supplied from the blower 25 into the tool 1. An annular projection 66 (air seal portion) is formed on the inner circumferential surface of the shoulder base 65, projecting radially inward. The inner diameter of the projection 66 is slightly larger than the outer diameter of the annular projection 59 of the pin base 58. A sealing member is attached to the inner circumferential surface of the projection 66 or the outer circumferential surface of the annular projection 59. In a modified embodiment, either the annular projection 59 or the projection 66 may be made to protrude, while the other is merely a surface to which the sealing member abuts.

[0035] Figure 4 is a cross-sectional view of the tool 1 of the first embodiment, showing the pin 11 mounted on the shoulder 12. Figure 4 shows the basic state of the tool 1, where the lower end 11T of the pin 11 and the lower end 12T of the shoulder 12 are flush. In this basic state, approximately the lower half of the small-diameter tip portion 51 of the pin 11 is inserted into the hollow tip portion 12B of the shoulder 12. In other words, the small-diameter tip portion 51 is inserted along the entire axial length of the hollow tip portion 12B. The medium-diameter portion 52 of the pin 11 is housed in the intermediate hollow portion 12H of the shoulder 12 along its entire axial length. The large-diameter portion 53 of the pin 11 has its lower portion housed in the intermediate hollow portion 12H, and its upper portion protrudes into the supply chamber 67.

[0036] Within the intermediate hollow section 12H, gaps exist in the interlayer 1A between the intermediate outer surface 52S of the medium diameter section 52 and the tip outer surface 51S of the tip small diameter section 51, and the intermediate inner surface 62S of the intermediate section 62, based on the difference in diameter between them. Specifically, a relatively small gap is formed between the intermediate outer surface 52S and the intermediate inner surface 62S, based on the diameter difference gap between the intermediate hollow section 12H and the medium diameter section 52. Also, a relatively large gap is formed between the tip outer surface 51S and the intermediate inner surface 62S, because the tip small diameter section 51 has a small diameter. An oil agent 7 is interposed in the interlayer 1A to fill these gaps. The diameter difference gap is set to a width that allows the oil agent 7 of a predetermined viscosity to be retained in the interlayer 1A without flowing out.

[0037] Tool 1 includes a first seal portion 1B and a second seal portion 1C that are arranged to sandwich an interlayer 1A in which an oil agent 7 is held in the vertical direction, that is, in the axial direction of the tool 1. The first seal portion 1B is a seal portion formed by the tip outer peripheral surface 51S of the tip small-diameter portion 51 of the pin 11 and the tip inner peripheral surface 61S of the tip portion 61 of the shoulder 12 facing each other with a clearance that substantially does not allow the oil agent 7 to pass through. Note that "substantially does not allow to pass through" means that the oil agent 7 can pass through by using means such as applying high pressure, but the oil agent 7 does not leak during normal operation. The second seal portion 1C is a seal portion formed by the base-end outer peripheral surface 53S of the large-diameter portion 53 of the pin 11 and the intermediate inner peripheral surface 62S of the shoulder 12 facing each other with a clearance that substantially does not allow the oil agent 7 to pass through. In a state where the first seal portion 1B and the second seal portion 1C are maintained, the oil agent 7 does not leak from the interlayer 1A.

[0038] In the basic state of the tool 1 shown in FIG. 4, the first seal portion 1B is formed with a first seal length L1 in the axial direction of the tool 1 from the tip opening 12A of the shoulder 12. In the present embodiment, the first seal length L1 corresponds to the axial length of the tip hollow portion 12B in the tip portion 61. Note that the first seal length L1 is the section length capable of sealing the oil agent 7, and as the pin 11 rises, the substantial seal length of the first seal portion 1B becomes shorter. The second seal portion 1C is formed with a second seal length L2 (L2 < L1) shorter than the first seal length L1 in the axial direction of the tool 1. That is, even if the pin 11 is raised so that the second seal portion 1C is released, the first seal portion 1B can be maintained.

[0039] The controller C controls the relative movement position of the pin 11 with respect to the shoulder 12 to operate the tool 1 to conform to each of the joining stage (FIG. 4), the discharge stage (FIG. 5), and the oil supply stage (FIG. 6). In the joining stage, a friction stir joining operation such as the shoulder leading process illustrated in FIG. 2 is performed on the tool 1. In the discharge stage, a forced discharge operation of the contaminated oil agent 7 from the interlayer 1A is performed. In the oil supply stage, a supply operation of fresh oil agent 7 to the interlayer 1A is performed. Hereinafter, the operations of each stage will be described.

[0040] <Joining Stage> Figure 4 above is also a cross-sectional view showing the state of tool 1 in the bonding stage. In the bonding stage, controller C performs control (first motion control) to move pin 11 relative to shoulder 12 while the lubricant 7 is held in the interlayer 1A. In other words, pin 11 is raised and lowered within the range in which the first seal portion 1B and the second seal portion 1C are maintained.

[0041] Specifically, the controller C moves the lower end 11T of the pin 11 relative to the shoulder 12 from the basic state of the tool 1 within the range of a first pull-up amount S1 from the tip opening 12A. The first pull-up amount S1 is shorter than not only the first seal length L1 but also shorter than the second seal length L2. That is, in the joining stage, the controller C moves the pin 11 relative to the shoulder 12 so as to satisfy the following relationship (1). S1 <L2<L1 ···(1)

[0042] In process P12 shown in Figure 2, the raising of the pin 11 is performed within the range of the first lifting amount S1. As a result, even when the pin 11 is raised to its maximum position, the first seal portion 1B and the second seal portion 1C are maintained. Therefore, even when the friction stir welding operation is performed with the tool 1 in an upward position, the oil 7 does not leak from the interlayer 1A. In other words, the oil 7 is retained in the interlayer 1A between the first seal portion 1B and the second seal portion 1C.

[0043] In the lubricant 7 of FIG. 4, the powder pieces 8 are shown. As described above, the powder pieces 8 are agglomerated pieces formed by the powder generated during the press-fitting of the tool 1 into the overlapping portion 30 being entrapped in the layer gap 1A and accumulating. As the number of joining strokes in the joining stage increases, the powder pieces 8 deposited in the lubricant 7 tend to increase. When the powder pieces 8 adhere to the outer peripheral surface 51S of the tip of the pin 11, the moving load of the pin 11 increases, and the tool 1 may malfunction. Therefore, when the number of joining strokes exceeds the assumed number at which a significant amount of powder pieces 8 is reached, it is desirable to discharge the lubricant 7 containing the powder pieces 8 from the layer gap 1A and supply new lubricant 7 to the layer gap 1A. For this purpose, the following discharge stage is executed, followed by the oil supply stage.

[0044] <Discharge stage> FIG. 5 is a cross-sectional view showing the state of the tool 1 in the discharge stage. In the discharge stage, the controller C executes control (second operation control) to relatively move the pin 11 with respect to the shoulder 12 so that the lubricant 7 is discharged from the layer gap 1A to the outside through the tip opening 12A of the shoulder 12. That is, the tip opening 12A substantially sealed by the first seal portion 1B is opened, and the lubricant 7 held in the intermediate hollow portion 12H is discharged to the outside through the tip hollow portion 12B and the tip opening 12A. At this time, the controller C operates the blower device 25 to supply an air flow F that promotes the discharge of the lubricant 7 into the supply chamber 67.

[0045] In the discharge stage, the controller C raises the pin 11 until the first seal portion 1B and the second seal portion 1C are released. Specifically, the controller C relatively moves the lower end portion 11T of the pin 11 upward with respect to the shoulder 12 by a second lifting amount S2 (S1 < S2) that is greater than the first lifting amount S1 from the tip opening 12A. The second lifting amount S2 is greater than the first seal length L1 of the first seal portion 1B. As described above, since the first lifting amount S1 is smaller than the first seal length L1, the relationship between the lifting amounts S1, S2 and the first seal length L1 is S1 < L1 < S2 ···(2) Therefore, the controller C moves pin 11 relative to shoulder 12 so as to satisfy the relationship in equation (2).

[0046] Furthermore, the second seal length L2 of the second seal portion 1C is smaller than the first seal length L1. Therefore, the relationship including the second seal length L2 in equation (2) above is: S1 <L2<L1<S2 ···(3) As is clear from the relationship in equation (3), when the pin 11 is raised by the second lifting amount S2, the first seal portion 1B and the second seal portion 1C are released. In other words, the small diameter tip portion 51 of the pin 11 comes out upward from the tip portion 61 of the shoulder 12, and the first seal portion 1B, which was formed by the narrow clearance between the outer peripheral surface 51S and the inner peripheral surface 61S of the tip, ceases to exist. Also, the base outer peripheral surface 53S of the large diameter portion 53 comes out upward from the intermediate inner peripheral surface 62S of the intermediate portion 62, so the second seal portion 1C also ceases to exist. As a result, the interlayer 1A holding the lubricant 7 becomes in communication with the outside through the tip opening 12A, and also in communication with the supply chamber 67 through the gap between the intermediate outer peripheral surface 52S and the intermediate inner peripheral surface 62S.

[0047] Raising the pin 11 by the second lifting amount S2 also leads to the sealing of the supply chamber 67. The supply chamber 67 is a space partitioned by the shoulder base 65 and the base end 63, and is a space that can communicate with the intermediate hollow section 12H below it, that is, a space that can communicate with the interlayer 1A. Furthermore, the supply chamber 67 is a space that can be sealed and released. The height positions of the annular projection 59 (air seal section) on the pin 11 side and the projection 66 (air seal section) on the shoulder 12 side are aligned, and the blower nozzle 27 is inserted into the inlet 64, thereby effectively sealing it. The supply chamber 67 is open in the joining stage shown in Figure 4, but is sealed in the discharge stage shown in Figure 5. This is to direct the airflow F exclusively towards the interlayer 1A.

[0048] As shown in Figures 4 and 5, the second lifting amount S2 corresponds to the height difference between the annular projection 59 and the ridge 66 in the basic state of tool 1. Therefore, when the pin 11 is raised by the second lifting amount S2, the height positions of the annular projection 59 and the ridge 66 become aligned, and the air seal portion 1D is formed. In other words, the annular projection 59 and the ridge 66 form an air seal portion that seals the supply chamber 67 when the relative position of the pin 11 with respect to the shoulder 12 reaches a predetermined axial position (seal position). The controller C constructs the air seal portion by moving the pin 11 relative to the tool 1 by the second lifting amount S2 from the basic state of tool 1.

[0049] The blower 25 includes a blower nozzle 27 that injects an airflow F. Tool 1 is moved to a waste liquid port that collects the oil 7 containing powder fragments 8, for example, when the discharge stage is being executed. The blower 25 is positioned near the waste liquid port, and when Tool 1 is positioned in a predetermined position at the waste liquid port, the blower nozzle 27 mounted on the moving mechanism is inserted into the inlet 64. Thereafter, the controller C operates the blower 25 to supply an airflow F from the blower nozzle 27 into the supply chamber 67.

[0050] As described above, the supply chamber 67 is sealed by the air seal and is in communication with the intermediate hollow section 12H where the interlayer 1A is formed. Therefore, the airflow F enters the intermediate hollow section 12H and presses against the lubricant 7 present in the interlayer 1A. Since the tip opening 12A is open, the pressing force of the airflow F acts to push the lubricant 7 outwards. Consequently, the lubricant 7 containing the powder fragments 8 is forcibly discharged from the interlayer 1A to the outside through the tip opening 12A. With the assistance of the airflow F, the discharge of the lubricant 7 from the tool 1 can be made faster compared to when discharge is reliant solely on gravity.

[0051] <Refueling Stage> Figure 6 is a cross-sectional view showing the state of tool 1 during the refueling stage. During the refueling stage, controller C moves the pin 11 relative to a position where it can supply the lubricant 7 from the supply chamber 67 to the interlayer 1A. That is, controller C maintains the first seal portion 1B while releasing the second oil seal portion 1C, moving the pin 11 upward relative to the shoulder 12 so that the supply chamber 67 and the interlayer 1A are in communication. Furthermore, controller C operates the refueling device 26 to supply fresh lubricant 7 to the interlayer 1A through the supply chamber 67.

[0052] Specifically, the controller C moves the lower end 11T of the pin 11 upward relative to the shoulder 12 by a third lifting amount S3 from the tip opening 12A. The third lifting amount S3 is set to be smaller than the first seal length L1 of the first seal portion 1B. Therefore, the first seal portion 1B is maintained. On the other hand, the third lifting amount S3 is set to be larger than the second seal length L2 of the second seal portion 1C. Therefore, the second seal portion 1C is released. In other words, the relationship between the third lifting amount S3 and the seal lengths L1 and L2 is: L2 <S3<L1 ···(4) This is the result.

[0053] The refueling device 26 includes a refueling nozzle 28 that discharges replenishment oil 70 for replenishing the lubricant 7. Tool 1 is moved to a refueling port that supplies fresh lubricant 7, for example, when a refueling stage is performed. The refueling device 26 is positioned near the refueling port, and when Tool 1 is positioned at a predetermined location in the refueling port, the refueling nozzle 28 mounted on the moving mechanism is inserted into the inlet 64. Thereafter, the controller C operates the refueling device 26 to supply replenishment oil 70 from the refueling nozzle 28 into the supply chamber 67.

[0054] As the pin 11 is raised by the third lifting amount S3 that satisfies equation (4) above, a passage for replenishment oil 70 is formed on the upper end side of the interlayer 1A. That is, the replenishment oil 70 discharged from the replenishment nozzle 28 enters the interlayer 1A through the gap between the surface of the second tapered portion 55 of the pin 11 and the intermediate inner circumferential surface 62S. On the other hand, the first seal portion 1B on the lower end side of the interlayer 1A functions, so the replenished oil 7 does not leak out from the tip opening 12A. Therefore, fresh oil 7 can be newly retained in the interlayer 1A.

[0055] <Advantages of the First Embodiment> According to the friction stir point welding apparatus M equipped with the tool 1 of the first embodiment and its operation method, since the oil agent 7 is interposed in the interlayer 1A between the pin 11 and the shoulder 12, the tool 1 can be made into a structure that is inherently less susceptible to adhesion of powder fragments 8 of the objects to be joined. Furthermore, in the joining stage, the pin 11 is moved relative to the first lifting amount S1 within a range that maintains the state in which the oil agent 7 is held in the interlayer 1A, that is, within a range that maintains the first seal portion 1B and the second seal portion 1C. Therefore, the increase in the operating load of the tool 1 during friction stir welding can be suppressed.

[0056] Meanwhile, in the discharge stage, the pin 11 is moved relative to the pin at a second lifting amount S2 in which the first seal portion 1B and the second seal portion 1C are released. As a result, the oil 7 containing the powder fragments 8 is discharged from the interlayer 1A through the tip opening 12A. In other words, simply by having the pin 11 perform a relative movement operation of lifting amounts S1 and S2, the oil contaminated with powder fragments 8 can be discharged from the tool 1. Therefore, adhesion of powder fragments 8 to the pin 11 and shoulder 12 can be suppressed without particularly complicating the structure of the tool 1.

[0057] Furthermore, the shape of the pin 11, in which the outer diameter gradually decreases towards the lower end 11T, restricts the entry of powder fragments 8 into the interlayer 1A between the intermediate outer surface 52S of the pin 11 and the intermediate inner surface 62S of the shoulder 12. In the basic state of tool 1 shown in Figure 4, a relatively large space exists between the tip outer surface 51S of the pin 11 and the intermediate inner surface 62S, which is near the lower part of the intermediate hollow section 12H. As a result, powder fragments 8, which consist of aggregates of powder from the joining target members embraced by the pin 11, mainly grow near the lower part of the intermediate hollow section 12H. On the other hand, above the intermediate hollow section 12H, the width of the interlayer 1A is narrow, making it difficult for the grown powder fragments 8 to enter. Therefore, even when powder fragments 8 are generated, the lubrication of the interlayer 1A is maintained. In this case, the powder fragments 8 tend to adhere to the area around the first tapered portion 54 of the pin 11, but if the lubrication of the interlayer 1A is maintained, the adhering material can be easily removed with a small amount of external force.

[0058] Furthermore, in the discharge stage, the airflow F generated by the blower 25 applies pressure to the lubricant 7 in the interlayer 1A, allowing the lubricant 7 to be quickly discharged from the tool 1. At this time, the pin 11 is raised by the second lifting amount S2, forming an air seal that seals the supply chamber 67. Therefore, the pressure of the airflow F acts more easily on the lubricant 7 in the interlayer 1A, allowing the lubricant 7 to be discharged more quickly. In addition, since the supply chamber 67 can be sealed by the relative movement of the pin 11 alone, the operation of the mechanism can be simplified. In the lubrication stage as well, by the relative movement of the pin 11 alone, the supply chamber 67 and the interlayer 1A can be connected while maintaining the first seal portion 1B, creating a state in which the lubricant 7 can be supplied to the interlayer 1A from the lubrication device 26. Therefore, the operation of supplying lubricant to the interlayer 1A can be simplified.

[0059] [Second embodiment of the tool] Figure 7(A) is a cross-sectional view showing the tool 10 according to the second embodiment. In the second embodiment, an example is shown in which an oil-impregnated sponge 9 (elastic oil-impregnated member) is applied in place of the second sealing portion 1C provided in the tool 1 of the first embodiment.

[0060] <Tool structure> Tool 10 includes a pin 110, a shoulder 12, and an oil-impregnated sponge 9 impregnated with the lubricant 7. The pin 110 is a cylindrical body whose diameter tapers in two stages towards the lower end 110T, and has a small-diameter tip portion 510 and a large-diameter tip portion 520. The small-diameter tip portion 510 is the cylindrical portion with the smallest outer diameter that forms the tip of the pin 110, and its tip surface is the lower end 110T of the pin 110. The large-diameter tip portion 520 is a cylindrical portion with a larger outer diameter than the small-diameter tip portion 510, connected to the small-diameter tip portion 510 via a tapered portion 540. A flange portion 56 is provided near the upper end of the large-diameter tip portion 520.

[0061] The shoulder 120 is a cylindrical body with a hollow portion 120S capable of accommodating the pin 110, and has a tip portion 61, an intermediate portion 62, a base portion 63, and an inlet 64 similar to those in the first embodiment. The outer circumferential surface 510S of the small-diameter tip portion 510 and the inner circumferential surface 61S of the tip portion 61 of the shoulder 12 face each other with a clearance that prevents the oil 7 from passing through. In the basic state of the tool 10, where the lower end portion 110T of the pin 110 and the lower end portion 120T of the shoulder 120 are flush, the outer circumferential surface 510S and the inner circumferential surface 61S form a tip seal portion 10B.

[0062] Most of the large-diameter portion 520 and the upper part of the small-diameter tip portion 510 of the pin 110 are housed in the hollow portion 120S of the shoulder 120 in the basic state described above. The space between the outer peripheral surface 510S of the tip and the outer peripheral surface 520S of the base end of the pin 110 and the inner peripheral surface 62S of the intermediate portion 62 of the shoulder 12 is an interlayer 10A that holds the oil 7.

[0063] The oil-impregnated sponge 9 is an elastic body with voids for holding the oil 7, and has an annular shape that surrounds the large-diameter portion 520 directly below the flange portion 56. Instead of the oil-impregnated sponge 9, another elastic body capable of holding the oil 7, such as an oil-impregnated annular body made of glass wool, can also be used. The oil 7 is supplied to the oil-impregnated sponge 9 from the oil supply device 26. The outer surface of the oil-impregnated sponge 9 faces an inlet 64 opened at the base end portion 63. The oil 7 is supplied to the oil-impregnated sponge 9 from an oil supply nozzle 28 inserted through the inlet 64. The oil-impregnated sponge 9 is fixed to the pin 110 and follows the vertical movement of the pin 110.

[0064] The lower surface of the oil-impregnated sponge 9 is in contact with the inner wall surface of the tapered portion 63T of the shoulder 120. In other words, the oil-impregnated sponge 9 functions as a sealing member that seals the upper opening of the hollow portion 120S. The interlayer 10A is sealed by being sandwiched between the oil-impregnated sponge 9 on the upper end side and the tip sealing portion 10B on the lower end side. Therefore, the oil 7 does not leak from the interlayer 10A not only when the tip opening 120A is facing downwards during the joining stage, but also when the tool 10 is used with the tip opening 120A facing upwards.

[0065] Figure 7(B) is a cross-sectional view showing the lubrication operation of tool 10. When lubricating the oil 7 into the interlayer 10A, the pin 110 is moved downward relative to the shoulder 120 so that the lower end 110T of the pin 110 protrudes beyond the lower end 12T of the shoulder 120. This downward movement causes the flange portion 560 (compression portion), which is integrated with the pin 110, to compress the oil-impregnated sponge 9. This compression squeezes oil droplets 71 out of the oil-impregnated sponge 9 and supplies them to the interlayer 10A. Note that in the shoulder-first process shown in Figure 2, there is no operation to make the lower end 110T of the pin 110 protrude from the tip opening 120A, and this operation is performed only during lubrication.

[0066] <Tool operation> Next, the operation of the tool 10 of the second embodiment will be explained based on Figures 8(A) to (C). Note that the operation of the lubrication stage is as shown in Figure 7(B) above, so it will be omitted here. Figure 8(A) is a cross-sectional view showing the state of the tool 10 in the joining stage. The controller C moves the lower end portion 110T of the pin 110 relative to the shoulder 120 from the basic state of the tool 10 by a predetermined amount S4 of pulling up from the tip opening 12A. The amount of pulling up S4 is smaller than the seal length of the tip seal portion 10B.

[0067] The lifting amount S4 may be set to a range in which the seal of the upper opening of the hollow portion 120S by the oil-impregnated sponge 9 is not released, or to a range in which the seal is released. In the second embodiment, the oil agent 7 can be supplied by appropriately performing the compression operation shown in Figure 7(B) without having to move the tool 10 to the oil supply port or the like. Therefore, it is easy to maintain lubrication even if the clearance between the layers 10A is made small. Accordingly, the clearance between the layers 10A can be set to a clearance in which the oil agent 7 cannot easily pass through, and the layer 10A itself can be used as the seal on the upper end side. In such a case, the lifting amount S4 may be set to a height in which the oil-impregnated sponge 9 is separated from the tapered portion 63T.

[0068] As the number of joining points of the tool 10 in the joining stage increases, powder fragments 8 accumulate in the lubricant 7. For this reason, a discharge stage similar to that of the first embodiment is performed. Figures 8(B) and (C) are cross-sectional views sequentially showing the state of the tool 10 in the discharge stage. As shown in Figure 8(B), the controller C moves the pin 110 relative to the shoulder 120 so that the lubricant 7 is discharged to the outside from the interlayer 10A through the tip opening 120A. The lifting amount S5 in the discharge stage is the height at which the tip seal portion 10B is released, and the annular projection 59 and the ridge 66 are at the same height position to form the air seal portion 1D.

[0069] Next, as shown in Figure 8(C), the blower nozzle 27 of the blower 25 is inserted into the inlet 64. This seals the supply chamber 67. The controller C operates the blower 25 to supply an airflow F from the blower nozzle 27 into the supply chamber 67. Due to the pressure of the airflow F, the oil 7 in the interlayer 10A containing the powder fragments 8 is discharged to the outside through the tip opening 120A.

[0070] According to the friction stir point bonding apparatus M equipped with the tool 10 of the second embodiment, the relative movement of the pin 110 with respect to the shoulder 120 allows the oil-impregnated sponge 9 to be compressed at an appropriate timing, thereby supplying the oil to the interlayer 10A. This reduces the frequency of moving the tool 10 to the oil supply port, etc., and allows for more frequent oil supply. Furthermore, the oil-impregnated sponge 9 can act as a sealing material to seal the interlayer 10A. Therefore, even when the tool 10 is positioned such that the tip opening 120A is facing upward, leakage of the oil 7 from the interlayer 10A can be suppressed.

[0071] [Summary of this disclosure] The specific embodiments described above include disclosures having the following configurations.

[0072] A friction stir point bonding apparatus according to one aspect of the present disclosure comprises a tool for friction stir point bonding, which includes a pin, a shoulder having a hollow portion through which the pin is inserted, and an oil interposed between layers of the outer circumferential surface of the pin and the inner circumferential surface of the shoulder, and a control unit for the tool, wherein the control unit performs a first operation control to move the pin relative to the shoulder while the oil is held between the layers, and a second operation control to move the pin relative to the shoulder such that the oil is discharged to the outside through the tip opening of the hollow portion from between the layers.

[0073] A method for operating a friction stir point welding apparatus according to another aspect of the present disclosure is a method for operating a friction stir point welding apparatus comprising a pin, a shoulder having a hollow portion through which the pin is inserted, and an oil interposed between the outer circumferential surface of the pin and the inner circumferential surface of the shoulder, wherein during friction stir welding, the pin is moved relative to the shoulder while the oil is held between the layers, and when the oil is to be discharged from between the layers, the pin is moved relative to the shoulder so that the oil is discharged to the outside through the tip opening of the hollow portion from between the layers.

[0074] According to the friction stir point welding apparatus and its operation method described above, since an oil is interposed between the layers of the pin and the shoulder, the tool can be made into a structure that is less susceptible to adhesion of powder fragments of the object to be joined. Furthermore, in the first operation control, the pin moves relative to the other while the oil is held between the layers, so the increase in the operating load of the tool during friction stir welding can be suppressed. Moreover, even though an oil is interposed, if the number of joining points increases, powder fragments of the object to be joined may accumulate in the oil between the layers. In view of this, in the second operation control, the oil is discharged from the layer through the tip opening. In other words, simply by having the pin perform the relative movement operation, the oil containing the powder fragments can be discharged from the tool. Therefore, adhesion of the powder fragments to the tool can be suppressed without particularly complicating the structure.

[0075] In the friction stir point bonding apparatus described above, a blower is further provided to supply an airflow between the layers to promote the discharge of the oil, and the control unit may operate the blower during the second operation control.

[0076] This friction stir point bonding apparatus allows the oil containing powder fragments to be forcibly discharged from the interlayers by the pressing force of the airflow generated by the blower. Therefore, the oil can be discharged from the tool quickly.

[0077] In the above friction stir spot welding apparatus, the tool has a first oil seal portion formed with a first seal length L1 in the axial direction of the tool from the tip opening, and with a clearance that substantially does not allow the oil agent to pass through, where the outer peripheral surface of the pin and the inner peripheral surface of the shoulder face each other. The control unit, in the first operation control, relatively moves the pin relative to the shoulder by a first lifting amount S1 from the tip opening, and in the second operation control, relatively moves the pin relative to the shoulder by a second lifting amount S2 that is larger than S1 from the tip opening, and it is desirable to execute the relative movement so as to satisfy the relationship S1 < L1 < S2.

[0078] According to this friction stir spot welding apparatus, during the first operation control for performing friction stir welding, since the pin is relatively moved relative to the shoulder with the relationship S1 < L1, the sealing function of the first oil seal portion is maintained, and the state of holding the oil agent between the layers can also be maintained. On the other hand, during the second operation control for discharging the oil agent, since the pin is relatively moved relative to the shoulder with the relationship L1 < S2, the first oil seal portion is eliminated. Therefore, the oil agent between the layers can be discharged from the tip opening.

[0079] In the above friction stir spot welding apparatus, the tool further includes a second oil seal portion formed with a second seal length L2 that is shorter than the first seal length L1 in the axial direction of the tool, and with a clearance that substantially does not allow the oil agent to pass through, where the outer peripheral surface of the pin and the inner peripheral surface of the shoulder face each other. The control unit, in the first operation control, holds the oil agent between the layers between the first oil seal portion and the second oil seal portion, and in the second operation control, supplies an air flow between the layers from the blower device by releasing the first oil seal portion and the second oil seal portion by the relative movement with the second lifting amount S2, and the configuration may be such that the relative movement is executed so as to satisfy the relationship S1 < L2 < L1 < S2.

[0080] In this friction stir point bonding device, during the second operation control for discharging the lubricant, an airflow is supplied between the layers from a blower. This airflow acts to push the lubricant present between the layers outwards. Therefore, the lubricant can be efficiently discharged from the tip opening of the tool.

[0081] In the friction stir point bonding apparatus described above, the tool includes a supply chamber that can communicate with the interlayer and can be sealed and released, and an air seal section that seals the supply chamber when the relative position of the pin with respect to the shoulder is a predetermined sealing position in the axial direction of the tool, and the control unit may be configured to seal the supply chamber while maintaining communication with the interlayer by moving the pin relative to the sealing position in the second operation control.

[0082] With this friction stir point bonding device, the supply chamber is sealed by the air seal when the second operation control is executed. In other words, the supply chamber can be sealed by the relative movement of the pins alone, thus simplifying the mechanism operation in the second operation control.

[0083] In the friction stir point bonding apparatus described above, the apparatus further comprises a lubrication device for supplying an oil agent to the interlayer, and the control unit may, when the oil agent is supplied by the lubrication device, maintain the first oil seal portion by relative movement at a third lifting amount S3 that is longer than the second seal length L2 and shorter than the first seal length L1, while releasing the second oil seal portion and moving the pin relative to allow communication between the supply chamber and the interlayer. In this case, it is desirable that the lubrication device supplies the oil agent to the interlayer through the supply chamber.

[0084] This friction stir point bonding device allows the supply chamber and the interlayer to which the oil should be held to be connected solely by the relative movement of the pins, creating a state where the oil can be supplied to the interlayer from the oil supply device. Therefore, the operation of supplying oil to the interlayer can be simplified.

[0085] In the friction stir point bonding apparatus described above, an elastic oil-impregnated member is provided to hold the oil supplied to the interlayer, and at least one of the pin and the shoulder is provided with a pressing section capable of compressing the elastic oil-impregnated member, and the control unit may move the pin relative to the elastic oil-impregnated member to a position where the pressing section compresses the elastic oil-impregnated member when the oil is supplied by the elastic oil-impregnated member.

[0086] This friction stir point bonding device allows the elastic oil-impregnated member to be compressed at an appropriate timing by the relative movement of the pins, thereby supplying oil to the interlayer. Furthermore, the elastic oil-impregnated member can act as a sealing material to seal the interlayer, preventing oil leakage from the interlayer even when the tool is positioned so that the tip opening points upward. [Explanation of Symbols]

[0087] 1 Tool 1A, 10A interlayer 1B First seal section (first oil seal section) 1C Second seal section (second oil seal section) 1D Air seal section 11, 110 pins 12, 120 shoulders 12A tip opening 12B Tip hollow part (hollow part) 12H Intermediate hollow part (hollow part) 2 Tool drive unit 25 Blower 26. Fueling device 3 conjugate 3 4 Stirring joint 560 Flange section (compression section) 59 Annular projection (air seal section) 66. Protrusions (air seal section) 67 Supply room 7. Oils 8 powder pieces 9. Oil-impregnated sponge (elastic oil-impregnated member) M Friction stir spot welding equipment Controller C (Control Unit) S1, S2 First and second increase amounts L1, L2 First and second seal lengths F Airflow

Claims

1. A friction stir point bonding tool comprising a pin, a shoulder having a hollow portion through which the pin is inserted, and an oil interposed between the outer surface of the pin and the inner surface of the shoulder, The tool comprises a control unit, The control unit, A first motion control that moves the pin relative to the shoulder while the oil is held between the layers, A second motion control that moves the pin relative to the shoulder so that the oil is discharged to the outside through the tip opening of the hollow portion from between the layers, A friction stir point bonding device that performs this operation.

2. In the friction stir point bonding apparatus according to claim 1, The layers are further provided with a blower that supplies an airflow to promote the discharge of the oil, The control unit operates the blower during the second operation control, and is a friction stir point bonding device.

3. In the friction stir point bonding apparatus according to claim 2, The tool has a first oil seal portion formed in the axial direction of the tool from the tip opening with a first seal length L1, and the outer surface of the pin and the inner surface of the shoulder face each other with a clearance that substantially prevents the oil from passing through. The control unit, In the first operation control, the pin is moved relative to the shoulder by a first pulling amount S1 from the tip opening. In the second operation control described above, the pin is moved relative to the shoulder by a second pulling amount S2 greater than S1 from the tip opening, A friction stir point bonding device that performs the relative movement such that the relationship S1 < L1 < S2 is satisfied.

4. In the friction stir point bonding apparatus according to claim 3, The aforementioned tool is The tool further comprises a second oil seal portion formed in the axial direction of the tool with a second seal length L2 shorter than the first seal length L1, wherein the outer circumferential surface of the pin and the inner circumferential surface of the shoulder face each other with a clearance that substantially prevents the oil from passing through. The interlayer is sandwiched between the first oil seal portion and the second oil seal portion. The control unit, In the first operation control, the oil is held between the layers between the first oil seal portion and the second oil seal portion. In the second operation control, the first oil seal portion and the second oil seal portion are released by the relative movement at the second lifting amount S2, thereby supplying airflow from the blower to the space between the layers. A friction stir point bonding device that performs the relative movement such that the relationship S1 < L2 < L1 < S2 is satisfied.

5. In the friction stirring point bonding apparatus according to claim 4, The aforementioned tool is A supply chamber that is able to communicate with the aforementioned interlayers and can be sealed and released, The system includes an air seal portion that seals the supply chamber when the relative position of the pin with respect to the shoulder reaches a predetermined sealing position in the axial direction of the tool, The control unit, in the second operation control, seals the supply chamber while maintaining communication with the interlayer by relatively moving the pin to the sealing position, thereby sealing the supply chamber.

6. In the friction stir point bonding apparatus according to Claim 5, The system further includes a lubrication device that supplies oil to the interlayers, The control unit, when the lubrication device supplies oil, maintains the first oil seal portion by relative movement at a third lifting amount S3 that is longer than the second seal length L2 and shorter than the first seal length L1, while releasing the second oil seal portion and moving the pin relative to allow communication between the supply chamber and the interlayer.

7. In the friction stirring point bonding apparatus according to claim 6, The oil supply device is a friction stirring point bonding device that supplies the oil to the interlayers via the supply chamber.

8. In the friction stir point bonding apparatus according to any one of claims 1 to 3, The system includes an elastic oil-impregnated member that holds the oil supplied between the layers, At least one of the pin and the shoulder is provided with a compression section capable of compressing the elastic oil-impregnated member, The control unit moves the pin relative to the elastic oil-impregnated member to a position where the pressing unit presses the elastic oil-impregnated member when the oil is supplied by the elastic oil-impregnated member.

9. A method for operating a friction stir point bonding apparatus comprising a pin, a shoulder having a hollow portion through which the pin is inserted, and an oil interposed between the outer surface of the pin and the inner surface of the shoulder, During friction stir welding, with the oil agent held between the layers, the pin is moved relative to the shoulder. When the oil is discharged from between the layers, the pin is moved relative to the shoulder so that the oil is discharged to the outside through the opening at the tip of the hollow portion from between the layers. Operation method of friction stir point bonding apparatus.

Images