Rotary member for friction stirring, robot-type joining device, and joint component

Abstract

Provided is a rotary member for friction stirring capable of performing high-strength joining while suppressing occurrence of joining defects in friction stir welding. A rotary member for friction stirring provided in a joining device that performs friction stir welding of members to be joined, the rotary member for friction stirring being configured such that, in a state in which the rotary member for friction stirring is provided on an output shaft of a drive mechanism of the joining device so as to be rotated by rotation output from the drive mechanism, a play that enables vibration of a pin part inserted into the members to be joined during friction stirring with respect to the output shaft is generated between the output shaft and the pin part.

Description

Friction stirring rotating member, robot type joining device, and joining part

[0001] The present invention relates to a friction stir welding rotating member, a robot-type welding device, and a welded component used in friction stir welding (FSW).

[0002] In Patent Document 1, the stirring pin is disposed on the main body so that it can rotate upon receiving rotational force from the main body and move axially along the rotating shaft. Furthermore, a first elastic member (e.g., a coil spring) is provided to bias the stirring pin toward the tip of the main body in the axial direction of the rotating shaft. Furthermore, the shoulder is disposed on the main body so that it can move independently of the stirring pin in the axial direction of the rotating shaft without receiving rotational force from the main body. Furthermore, a second elastic member is provided to bias the shoulder toward the tip of the main body in the axial direction of the rotating shaft. Even if the height of the workpieces changes while the stirring pin is being pressed into the workpieces at a constant height, the first elastic member deforms in accordance with the change in the height of the workpieces, thereby maintaining a constant insertion depth of the stirring pin (

[0041] ). The action of the first elastic member ensures that the stirring pin is inserted into the workpieces at a constant depth, thereby forming a plasticized region at a constant depth (

[0071] ). In this way, in the technique of Patent Document 1, the first elastic member biases the stirring pin toward the workpieces, and the stirring pin is inserted into the workpieces to a certain depth.

[0003] In Patent Document 2, the stirring pin and shoulder constitute an assembly. The assembly is rotatable relative to one another and is movable integrally in the axial direction of the rotating shaft. Furthermore, a first elastic member (e.g., a coil spring) is provided to bias the assembly toward the tip of the stirring pin in the axial direction of the rotating shaft. In the technology of Patent Document 2, the first elastic member also keeps the insertion depth of the stirring pin constant, and a plasticized region is formed at a constant depth (

[0033] ,

[0052] ).

[0004] In Patent Document 3, the rotary tool has a main body and a stirring member. The main body has a fixed portion that is attached to and fixed on a welding device, and a rotating shaft that transmits rotational force from the welding device. The stirring member has a stirring pin, is rotatably mounted upon receiving rotational force from the rotating shaft, and is mounted on the main body so as to be movable in the axial direction of the rotating shaft. Furthermore, an elastic member (coil spring) is provided that biases the stirring member toward the tip in the axial direction of the rotating shaft. In the technology of Patent Document 3, the elastic member also keeps the insertion depth of the stirring pin constant, and a plasticized region is formed at a constant depth (

[0035] ,

[0051] ).

[0005] In all of Patent Documents 1 to 3, the stirring pin is biased toward the workpieces to be joined by an elastic member (coil spring) and pressed against the workpieces to be joined, so that the insertion depth of the stirring pin is kept constant and a plasticized region is formed at a constant depth.

[0006] JP 2023-069370 A JP 2023-069371 A JP 2023-069372 A

[0007] With regard to friction stir welding, it is desired to provide a friction stir rotating member, a robot-type welding device, and welded components that enable high-strength welding while suppressing the occurrence of welding defects.

[0008] An object of the present invention is to provide a friction stir rotating member, a robot-type welding device, and a welded component that enable high-strength welding while suppressing the occurrence of welding defects in friction stir welding.

[0009] The present inventors have conducted extensive research in light of the above-mentioned problems and have obtained the following findings.

[0010] Conventionally, in friction stir welding, the support structure for the stirring pin has been designed based on the design concept of how to perform friction stirring with the stirring pin in a stable state. To achieve this, external force has been forcibly applied to the stirring pin, such as how to urge the stirring pin toward the workpieces to stably press and insert the workpieces. In Patent Documents 1 to 3, the elastic member is also provided to keep the insertion amount of the stirring pin constant and form a plasticized region at a constant depth. Patent Documents 1 to 3 fall within the scope of conventional design concepts.

[0011] In response to this, the inventors have shifted their thinking from the conventional design concept and discovered that by passively vibrating the pin portion inserted into the workpieces at a larger amplitude and / or frequency than the base vibration by contacting the workpieces undergoing plastic flow, it is possible to achieve a high-strength joint while suppressing the occurrence of joint defects, and have completed the present invention. This finding is completely different from the conventional friction stir welding described above. Therefore, even a person skilled in the art would not have easily arrived at this finding from conventional friction stir welding technology. The present invention can employ the following configurations.

[0012] (1) A friction stirring rotating member provided in a joining device that performs friction stir welding of workpieces, wherein the friction stirring rotating member is provided on an output shaft of a drive mechanism provided in the joining device so as to rotate with rotation output from the drive mechanism, and the friction stirring rotating member generates play between the output shaft and a pin portion that is inserted into the workpieces during friction stirring, allowing the pin portion to vibrate relative to the output shaft, and the play causes the vibration of the pin portion to have a larger amplitude and / or frequency than the vibration of the output shaft during friction stirring.

[0013] The friction stirring rotating member (1) has play between the output shaft and the pin portion, which allows the pin portion to vibrate relative to the output shaft. The friction stirring rotating member is configured such that the play causes the vibration of the pin portion during friction stirring to have a greater amplitude and / or frequency than the vibration of the output shaft. The output shaft of the drive mechanism vibrates in conjunction with the transmission of rotation from the drive mechanism during friction stirring. This vibration is also referred to as base vibration. Base vibration is vibration that inevitably occurs during friction stirring. During friction stirring, the vibration of the pin portion has a greater amplitude and / or frequency than the base vibration. During friction stirring, the pin portion rotates within the play while moving to pass the plastically flowing workpieces rather than resisting them. This movement causes the vibration of the pin portion. In other words, the vibration of the pin portion is caused by the play. The vibration of the pin portion is not vibration caused by output from a drive source other than the drive mechanism. The vibration of the pin portion is unlikely to interfere with the plastic flow of the workpieces. Furthermore, the vibration of the pin portion can be synchronized with the plastic flow of the workpieces to be welded. This allows the vibration of the pin portion to amplify the plastic flow of the workpieces to be welded. This vibration of the pin portion can therefore perform high-strength welding while suppressing the occurrence of welding defects. Additionally, the tilt angle (advance angle) of the friction stir rotating member and the output shaft may be 0 degrees. Even with a tilt angle of 0 degrees, good friction stir welding can be achieved. Because the above-mentioned vibration of the pin portion can be achieved by play, a complex spindle mechanism is not required. The generation of excessive frictional heat can be suppressed. The generation of excessive friction applied to the pin portion can be suppressed. By vibrating the pin portion, the transmission of vibration from the downstream side of the play to the upstream side in the power transmission path from the drive mechanism to the pin portion can be suppressed. The load applied to the output shaft can be reduced.

[0014] The friction stirring rotating member itself may have play within the friction stirring rotating member. The friction stirring rotating member may be configured so that play occurs between the friction stirring rotating member and the output shaft when the friction stirring rotating member is attached to an output shaft. The friction stirring rotating member may not have a pin portion, but rather, a pin portion may be attached to the friction stirring rotating member so that play occurs between the friction stirring rotating member and the pin portion. The joining device is not limited to a dedicated friction stir welding device, and may be, for example, a machining center, a robot, a milling machine, a multi-tasking machine, a general-purpose machine, or a portable device large enough for a user to hold in their hand to perform friction stir welding. The control conditions (position, load, spindle load, heat, pressure, etc.) of the joining device or its auxiliary mechanisms are not particularly limited. The joining conditions (feed speed, rotation speed, joining temperature, advance angle) are also not particularly limited. The materials of the workpieces are not particularly limited. The workpieces may be the same material or different materials. In the embodiments described below, the play is provided by a key (a mating key or a fixed key), but this example is not limiting. The structure for providing the play is not particularly limited, and a conventionally known structure can be employed. In addition to a key, components for providing the play, such as bolts, pins, and spherical bodies, can be employed. The play itself may also be provided by the shape of the friction stirring rotating member itself. The friction stirring rotating member may be divided into multiple (e.g., two) components, and the play may be formed by the fit between adjacent components. The amplitude and frequency of the vibration are not particularly limited, and can be adjusted by changing the amount of play or the weight of the component downstream of the play in the power transmission path from the drive mechanism to the pin portion. For example, the weight can be changed by installing a weight. In the joining device, the drive mechanism includes a rotating machine. The rotating machine may be, for example, a rotating electric machine or an internal combustion engine. The drive mechanism may include a transmission that changes the rotational speed output from the rotating machine and outputs the rotation. The transmission may be a speed reducer or a speed increaser. When the drive mechanism includes a transmission, the output shaft of the transmission corresponds to the output shaft of the drive mechanism. When the drive mechanism does not include a transmission, the output shaft of the rotating machine corresponds to the output shaft of the drive mechanism.In one embodiment, the backlash and margin in the drive mechanism do not constitute play. In one embodiment, the play is provided downstream of the upstream edge of the output shaft of the drive mechanism in the power transmission path from the drive mechanism to the pin portion.

[0015] (2) The friction stirring rotating member of (1), wherein the friction stirring rotating member comprises: a rotating shaft portion provided on the output shaft; and a tip portion configured to rotate by rotation transmitted from the rotating shaft portion and located distal to the rotating shaft portion, the tip portion having the pin portion and a base end side portion provided on the base end side of the pin portion, or having a base end side portion that does not have the pin portion but is configured to allow the pin portion to be detachably attached, the play is provided between the rotating shaft portion and the tip portion so as to enable vibration of the pin portion relative to the rotating shaft portion, and the friction stirring rotating member is configured so that, due to the play, the vibration of the pin portion during friction stirring has a larger amplitude and / or frequency than the vibration of the rotating shaft portion.

[0016] The friction stirring rotating member (2) has play between the rotating shaft and the tip. Due to this play, the vibration of the pin during friction stirring has a larger amplitude and / or frequency than the vibration of the output shaft. This vibration is not generated by the output from a drive source other than the drive mechanism. This vibration is unlikely to interfere with the plastic flow of the workpieces. Furthermore, this vibration can amplify the plastic flow of the workpieces. Therefore, high-strength joining can be achieved while suppressing the occurrence of joining defects.

[0017] When the pin portion and the base end portion are integrally configured, the pin portion is the portion that enters the workpiece, and the base end portion is the portion provided on the base end side of the pin portion, and thus the pin portion and the base end portion can be distinguished. On the other hand, when the pin portion and the base end portion are separable, for example, when the pin portion is detachable from the base end portion, the pin portion and the base end portion can be physically distinguished. For example, the pin portion corresponds to the tool, and the base end portion corresponds to the collet. When the tip portion does not have a pin portion, the tip portion may be the base end portion itself, which is configured to detachably attach the pin portion.

[0018] (3) The friction stirring rotating member of (2), wherein the tip portion has a surface contact portion at a height on the base end side of the pin portion where it contacts the surface of the workpiece, and the ratio of the diameter of the surface contact portion to the diameter of the pin portion adjacent to the surface contact portion closer to the tip than the surface contact portion is 1.8 or less, and thus the tip portion is configured to have a shoulder with a width small enough to satisfy the ratio, or to have no shoulder.

[0019] As described above, the vibration generated by the pin due to play does not interfere with the plastic flow of the workpieces and can amplify the plastic flow of the workpieces. Since the friction stir rotating member (3) has a narrow shoulder or no shoulder at all, the area of ​​the shoulder that contacts the surface of the workpieces, covering the workpieces undergoing plastic flow, is reduced. This makes it less likely for the shoulder to interfere with plastic flow. As a result, the effect of the pin vibration, which is to both minimize and amplify plastic flow, can be more effectively achieved. Furthermore, if the rotating shoulder is narrow or absent, the amount of heat applied to the workpieces by the rotating shoulder is reduced, but the effect of the pin vibration enables effective plastic flow. As a result, friction stir welding can be performed at lower temperatures. Friction stir welding at low temperatures can reduce the impact of temperature on the workpieces. This reduces the occurrence of thermal deformation and stress, potentially improving the mechanical properties of the welded components compared to those after conventional friction stir welding. Furthermore, lowering the temperature of friction stir welding reduces energy consumption. It may also become possible to use materials that are difficult to weld at high temperatures as welded components.

[0020] The ratio is not particularly limited, but is preferably 1.8 or less in the above (3). Furthermore, the ratio is more preferably 1.5 or less, even more preferably 1.3 or less, and particularly preferably 1.1 or less. This is because the occurrence of a situation in which the shoulder interferes with plastic flow can be suppressed. When the ratio is 1.0, the friction stir rotating element does not have a shoulder. A configuration without a shoulder is also a preferred embodiment of the friction stir rotating element. The ratio may be, for example, less than 2.0. In conventional friction stir welding, the ratio is, for example, 2 or more. The ratio may be 2 or more. By vibrating the shoulder together with the pin, the effect of preventing and amplifying plastic flow can be obtained. The shoulder may be configured not to rotate with the pin. Friction stir welding performed in a configuration in which the shoulder does not rotate with the pin is called Stationary Shoulder Friction Stir Welding (SSFSW). SSFSW allows for low heat input to the plastic flow zone (joint), thereby improving the mechanical properties, microstructure, and surface finish of the plastic flow zone. As described above, an embodiment with a small shoulder width or no shoulder allows friction stir welding to be performed at lower temperatures, and is therefore suitable for SSFSW. That is, when the friction stir rotating member has a shoulder, the shoulder may be configured to rotate together with the pin portion, or may be configured not to rotate together with the pin portion. A shoulder that does not rotate together with the pin portion may be installed on the friction stir rotating member or welding device as a separate unit from the friction stir rotating member. A shoulder that does not rotate together with the pin portion may be fixed to the friction stir rotating member or welding device in a manner that does not rotate at all, or may be configured to rotate separately from the pin portion.

[0021] (4) The friction stirring rotating member according to any one of (1) to (3), wherein the friction stirring rotating member is configured such that vibration of the pin portion is passively generated by contact with the workpieces undergoing plastic flow within the range of play.

[0022] In the friction stirring rotating member (4), the pin portion passively vibrates within the range of play due to contact with the plastically flowing workpieces. During friction stirring, the pin portion rotates within the range of play while moving to deflect rather than resist the plastically flowing workpieces. This movement passively generates vibration in the pin portion. Therefore, the vibration of the pin portion is unlikely to interfere with the plastic flow of the workpieces. Furthermore, this vibration can amplify the plastic flow of the workpieces. Therefore, high-strength joining can be achieved while suppressing the occurrence of joining defects.

[0023] (5) The friction stirring rotating member according to any one of (1) to (4), wherein the friction stirring rotating member is configured such that the pin portion vibrates in at least one of the axial direction, circumferential direction, and radial direction of the pin portion due to the play.

[0024] The friction stirring rotating member (5) can perform high-strength joining while suppressing the occurrence of joining defects by vibrating the pin portion toward at least one of the two sides.

[0025] When play is provided between the output shaft and the pin portion in the axial direction, the pin portion can vibrate in the axial direction. When play is provided in the circumferential direction, the pin portion can vibrate in the circumferential direction. When play is provided in the radial direction, the pin portion can vibrate in the radial direction. The play is provided in at least one of the axial, circumferential, and radial directions of the pin portion. For example, the following play can be provided between the output shaft and the pin portion: (A) play only in the axial direction; (B) play only in the circumferential direction; (C) play only in the radial direction; (D) a combination of axial play and circumferential play; (E) a combination of axial play and radial play; (F) a combination of circumferential play and radial play; or (G) a combination of circumferential play, circumferential play, and radial play. In the case of (A) above, the pin portion can vibrate at least in the axial direction. In the case of (B) above, the pin portion can vibrate at least in the circumferential direction. In the case of (C) above, the pin portion is capable of vibrating at least in the radial direction. In the case of (D) above, the pin portion is capable of vibrating at least in the axial and circumferential directions. In the case of (E) above, the pin portion is capable of vibrating at least in the axial and radial directions. In the case of (F) above, the pin portion is capable of vibrating at least in the circumferential and radial directions. In the case of (G) above, the pin portion is capable of vibrating in the axial, circumferential, and radial directions. Note that this paragraph describes the play provided between the output shaft and the pin portion. However, if the play is provided between the rotating shaft portion and the tip end, the "output shaft" in this paragraph can be read as "rotating shaft portion." The amount of play in either direction is not particularly limited and varies depending on the size of the joining device, but is preferably 0.0001 mm to 1 mm, more preferably 0.001 mm to 0.8 mm, and even more preferably 0.01 mm to 0.5 mm. Note that the axial direction is not necessarily limited to the vertical direction and can be determined by the arrangement of the workpieces and the pin portion.

[0026] (6) The friction stirring rotating member according to any one of (1) to (5), wherein the pin portion is configured to be free or substantially free relative to the output shaft within the range of play.

[0027] In the friction stirring rotating member (6), the pin portion is free or substantially free within the range of play, so that vibration of the pin portion occurs passively upon contact with the workpieces undergoing plastic flow, and has a larger amplitude and / or frequency than the base vibration. This vibration is less likely to interfere with the plastic flow of the workpieces. Furthermore, this vibration can amplify the plastic flow of the workpieces. This vibration enables high-strength joining while suppressing the occurrence of joining defects.

[0028] "Free" refers to a state in which there is no physical or mechanical constraint. "Substantially free" refers to a state in which the amplitude and / or frequency of the vibration of the pin portion during friction stirring is greater than the vibration of the output shaft, and within that range, constraint of the tip portion relative to the output shaft is permitted. The constraint is, for example, friction between adjacent members between the output shaft and the pin portion, or external stress caused by an elastic body or liquid, which will be described later.

[0029] (7) The friction stirring rotating member according to any one of (1) to (6), wherein the play is a gap or substantially a gap.

[0030] In the friction stirring rotating member of (7), the play is a gap or substantially a gap, so that the vibration of the pin portion occurs passively upon contact with the workpieces undergoing plastic flow, and has a larger amplitude and / or frequency than the base vibration. This vibration is less likely to interfere with the plastic flow of the workpieces. Furthermore, this vibration can amplify the plastic flow of the workpieces. This vibration enables high-strength joining while suppressing the occurrence of joining defects.

[0031] The gap is the space between the output shaft and the pin. "Substantially in the gap" means that the pin may have a liquid or an elastic body therein to the extent that the amplitude and / or frequency of the vibration of the pin during friction stirring can be made larger than the vibration of the output shaft.

[0032] (8) A joining device for friction stir welding of workpieces, the joining device comprising: a drive mechanism having an output shaft and configured to rotate the output shaft; and a pin portion configured to rotate by rotation transmitted from the drive mechanism and inserted into the workpieces during friction stirring, the pin portion having play between the output shaft and the pin portion to enable vibration of the pin portion relative to the output shaft, and configured such that vibration of the pin portion has a larger amplitude and / or frequency than vibration of the output shaft due to the play during friction stirring.

[0033] The joining device (8) has play between the output shaft and the pin portion, which allows the pin portion to vibrate relative to the output shaft. The joining device is configured so that the play causes the vibration of the pin portion to have a larger amplitude and / or frequency than the vibration of the output shaft during friction stirring. The output shaft vibrates in conjunction with the transmission of rotation from the drive mechanism during friction stirring. This vibration is similar to the base vibration described above. During friction stirring, the vibration of the pin portion has a larger amplitude and / or frequency than the base vibration. This vibration is generated by the play. This vibration is not generated by output from a drive source other than the drive mechanism. This vibration is unlikely to interfere with the plastic flow of the members to be joined. Furthermore, this vibration can amplify the plastic flow of the members to be joined. Therefore, high-strength joining can be performed while suppressing the occurrence of joining defects.

[0034] (9) A joining method for friction stir welding of workpieces by rotating a pin portion using rotation output from a drive mechanism and inserting the pin portion into workpieces, wherein, during friction stirring, vibrations having amplitudes and / or frequencies greater than base vibrations transmitted from the drive mechanism to the pin portion due to rotation of the drive mechanism are passively generated in the pin portion by contact with the workpieces undergoing plastic flow, and friction stirring is performed on the workpieces.

[0035] According to the joining method (9), the vibration of the pin portion is passively generated by contact with the workpieces undergoing plastic flow, and has a vibration and / or frequency greater than that of the base vibration. This vibration is less likely to interfere with the plastic flow of the workpieces. Furthermore, this vibration can amplify the plastic flow of the workpieces. This vibration enables high-strength joining while suppressing the occurrence of joining defects.

[0036] (10) A joining method for friction stir welding of workpieces by inserting a pin into workpieces while rotating the pin with rotation output from a drive mechanism, wherein the drive mechanism is feedback controlled so that the output of the drive mechanism changes in synchronization with or following the rotational fluctuation of the pin that occurs passively due to contact with the workpieces undergoing plastic flow, and friction stir welding is performed on the workpieces.

[0037] According to the joining method (10), the vibration of the pin is controlled by the drive mechanism so as to suppress or prevent the pin vibration from interfering with the plastic flow of the workpieces. This allows for freer plastic flow. Therefore, high-strength joining can be achieved while suppressing the occurrence of joining defects.

[0038] The above items (1) to (10) and the items described in the above columns (1) to (10) can be applied to and / or incorporated into (A1) to (A18) described below.

[0039] (A1) A friction stirring rotating member provided in a joining device that performs friction stir welding of workpieces, wherein the friction stirring rotating member is provided on an output shaft of a drive mechanism provided in the joining device so as to rotate by rotation output from the drive mechanism, and is configured to generate play between the output shaft and a pin portion that is inserted into the workpieces during friction stirring, allowing the pin portion to vibrate relative to the output shaft.

[0040] According to (A1), similarly to (1) above, it is possible to achieve a high-strength joint while suppressing the occurrence of joint defects.

[0041] (A2) The friction stirring rotating member of A1, further comprising a drop-off prevention structure that prevents the pin portion from dropping off from the output shaft.

[0042] According to (A2), the pin portion can be prevented from falling off, and therefore friction stir welding can be performed more efficiently.

[0043] (A3) The friction stirring rotating member of A1 or A2, wherein the friction stirring rotating member comprises: a rotating shaft portion provided on the output shaft; and a tip portion configured to rotate by rotation transmitted from the rotating shaft portion and located distal to the rotating shaft portion, the tip portion having the pin portion and a base end side portion provided on the base end side of the pin portion, or having a base end side portion without the pin portion but configured to allow the pin portion to be detachably attached, the play is provided between the rotating shaft portion and the tip portion so as to enable vibration of the pin portion relative to the rotating shaft portion, and the friction stirring rotating member is configured such that, due to the play, vibration of the pin portion during friction stirring has a larger amplitude and / or frequency than vibration of the rotating shaft portion.

[0044] (A4) The friction stirring rotating member of A3, wherein the pin portion has a surface contact portion at a height where it contacts the surface of the workpiece, and the ratio of the diameter of the surface contact portion to the diameter of the pin portion adjacent to the surface contact portion closer to the tip than the surface contact portion is 1.8 or less, thereby the pin portion has a shoulder with a width small enough to satisfy the ratio, or is configured to have no shoulder.

[0045] (A5) The friction stirring rotating member of any one of A1 to A4, wherein the vibration of the pin portion is passively generated by contact with the workpieces undergoing plastic flow within the range of play.

[0046] (A6) The friction stirring rotating member of any one of A1 to A5, wherein the friction stirring rotating member is configured so that vibration of the pin portion occurs in at least one of the axial direction, circumferential direction, and radial direction of the pin portion due to the play.

[0047] (A7) The friction stirring rotating member of any one of A1 to A6, wherein the pin portion is configured to be free or substantially free relative to the output shaft within the range of play.

[0048] (A8) The friction stirring rotating member according to any one of A1 to A7, wherein the play is a gap or substantially a gap.

[0049] According to (A3) to (A8), the same excellent effects as those of (2) to (7) above can be obtained.

[0050] (A9) A robot-type joining device that performs friction stir welding of the workpieces, the robot-type joining device comprising: a robot arm having at least one joint; the output shaft provided on a tip side of the robot arm; the drive mechanism configured to rotate the output shaft; and the friction stir rotating member of any one of A1 to A8 provided on the output shaft.

[0051] (A10) A robot-type joining device for friction stir welding of workpieces, the robot-type joining device comprising: a robot arm having at least one joint; an output shaft provided at the tip of the robot arm; a drive mechanism configured to rotate the output shaft; and a pin portion configured to rotate by rotation transmitted from the drive mechanism and inserted into the workpieces during friction stir welding, the pin portion being configured to have play between the output shaft and the pin portion so as to enable vibration of the pin portion relative to the output shaft.

[0052] (A11) The robot type joining device according to A10, wherein the pin portion is configured so that the pin portion vibrates at a larger amplitude and / or frequency than the output shaft during friction stirring due to the play.

[0053] (A12) A robot-type joining device that performs friction stir welding of members to be joined, the robot-type joining device comprising: a robot arm having at least one joint; an output shaft provided at a tip end of the robot arm; a drive mechanism configured to rotate the output shaft; a pin portion provided at the tip end of the output shaft; a control unit that controls the drive mechanism so that the pin portion is inserted into the members to be joined while rotating with the rotation output from the drive mechanism, thereby performing friction stir welding of the members to be joined; and a detection unit that detects the rotational state of the pin portion, wherein the control unit performs feedback control of the drive mechanism based on the rotational state of the pin portion detected by the detection unit so that the output of the drive mechanism changes in synchronization with or following the rotational fluctuation of the pin portion that passively occurs due to contact with the members to be joined that are plastically flowing, while performing friction stir welding on the members to be joined.

[0054] According to (A9) to (A12), it is easy to apply the method to a joining line having a complex shape, such as a joining line on a curved surface, and it is possible to realize a high-strength joining while suppressing the occurrence of joining defects.

[0055] (A13) The robot type joining device according to any one of A9 to A12, wherein the robot arm is a multi-joint robot arm having a plurality of joints.

[0056] According to (A13), a wider variety of operations are possible, and therefore, it is possible to adapt to a joining line with a more complex shape while suppressing the occurrence of joining defects and realizing a high-strength joining.

[0057] (A14) The robot type joining device according to any one of A9 to A13, wherein the robot arm has a position adjustment mechanism configured to adjust an insertion depth of the pin portion into the workpieces in a direction in which the workpieces and the pin portion face each other.

[0058] The position adjustment mechanism is configured to adjust the insertion depth of the pin portion separately from the joint movement of the robot arm. According to (A14), more accurate joining is possible. It is possible to suppress the occurrence of joining defects and achieve high-strength joining.

[0059] (A15) A welded component manufactured by friction stir welding using the friction stir rotating member of any one of A1 to A8.

[0060] (A16) The joining part of A15, wherein the joining part is applied to any one of automobiles, railway vehicles, aircraft, ships, and rockets.

[0061] The friction stirring rotating member can suppress the occurrence of joining defects and can achieve high-strength joining. Therefore, the resulting joined member can be suitably applied to vehicles, and in particular, can be suitably applied to constructing the body of a vehicle.

[0062] (A17) The joining part of A15, which is applied to any one of an electrode part, an air conditioning device, a water-cooled or air-cooled power control unit, a water-cooled or air-cooled battery case, a door panel, a shock absorber, a suspension link, a waveguide, an antenna, a motor cover, a sake brewing tank, a vacuum device part, a sputtering target material, and an embedded heater.

[0063] (A18) The joined part according to any one of A15 to A17, wherein the joined part is a part manufactured by friction stir welding a plurality of plate materials having different thicknesses, or a part manufactured by friction stir welding dissimilar materials.

[0064] The friction stir rotating member suppresses the occurrence of welding defects and enables high-strength welding. Therefore, high-quality friction stir welding can be performed even on multiple plate materials of different thicknesses or on dissimilar materials. The resulting welded parts are manufactured by high-quality friction stir welding. The dissimilar materials may be the following combinations: for example, a combination of dissimilar metals, a combination of resin and metal, a combination of metal casting and wrought metal, or a combination of ceramic and metal. Furthermore, at least one of the dissimilar materials may be the following: for example, a copper-aluminum dissimilar thin film material, a Ti-based material, an iron-based material, a chromium-based material, or a rare metal joint. The rare metals referred to here may or may not include Ag and Au.

[0065] The present invention may further employ the following configurations. The following configurations are inherently or implicitly included in the present invention, but are described below for clarity. (A16-1) The joined part of A15, which is applied to spacecraft, special vehicles, bicycles, special defense vehicles, defense equipment, linear motors, linear motor cars, and drones. Examples of the spacecraft include artificial satellites, space stations, manned spacecraft, space probes, space telescopes, space cargo ships, space planes, and interplanetary probes. Examples of the special vehicles include self-propelled construction machinery such as truck cranes, trailer-mounted vehicles, etc. Examples of the bicycles include city bicycles, electrically assisted bicycles, sports bikes, and specialized bicycles for off-road use or racing. The joined part of (A15) suppresses the occurrence of joining defects and provides high-strength joining, so the joined part of (A15) can be suitably used in applications under harsh environments such as those described in (A16-1). (A16-2) A joining part of A15 applied to facilities, devices, or equipment used in the following fields: food and beverage, liquid crystal / electronics / semiconductors, energy, power generation, batteries, solar cells, infrastructure, architecture, construction, medical care, vacuum, materials, equipment, machinery, metal / resin molding, home appliances, communications, IT, digital. The joining part of (A15) suppresses the occurrence of joining defects and provides high-strength joining, so the joining part of (A15) can be suitably used in a wide range of fields, including those shown in (A16-2). (A17-1) A joining part of A15 applied to any one of the following, or configured as any one of the following: Aluminum and aluminum alloy products, copper and copper alloy products, magnesium and magnesium alloy products, iron and iron alloy products, resin products, extrusion materials, drawing materials, casting materials, forging materials, thermal spraying and injection materials, shaping materials, metal products, dissimilar material joining products, thin film materials, bus bars, bus bars, silver and silver alloy products, gold and gold alloy products, titanium and titanium alloy products. (A17-2) Joined parts of A15 that apply to any one of the following:Chambers, vacuum chambers, backing plates, water-cooled plates, temperature control plates, heat sinks, nozzles, valves, susceptors, ion implantation equipment, mobile phones, smartphones, chargers, capacitors, Wi-Fi devices, electrical appliances, household products, televisions, games, washing machines, refrigerators, clocks, digital watches, decorative materials, accessories, tableware, knives, scissors, balls, glasses, bats, electronic devices, cameras. (A17-3) Joining parts of A15 that apply to any one of the following: Inverter cases, frames, bodies, suspension parts, doors, door panels, floor panels, ceiling panels, inner panels, outer panels, stack boxes, crank arms, waveguides, antennas, motors, gears, mufflers, electrical components, oil pans, motor covers, honeycomb panels, double skin panels, tailored materials, fuselage panels, wing parts, bridges, bridge beams, wheelchairs, turbines, blades, converters, battery pack housings, wheels, accelerators, brakes, drive shafts, bumpers, bumper beams, spoilers, crash boxes, saddles, crank cases, hoods, radomes, cladding materials, battery coil materials, rollers, bearings, beam guides, heat shields. (A17-4) Joined parts of A15 that apply to any one of the following: Gas tanks, gas generators, fuel tanks, liquor tanks, hydrogen tanks, gasoline tanks, nuclear containers, solvent tanks, sonar, thermal power generators, hydroelectric generators, wind power generators, nuclear power generators, ion implantation equipment, film deposition equipment, etching equipment, coating equipment, agricultural machinery, construction machinery, machine tools, industrial machinery, pumps and compressors, textile machinery, office machinery, superconducting devices, neutron devices, exposure equipment. (A17-5) A connecting part of A15 that is applied to any one of the following: syringes, catheters, medical equipment, stands, jigs, blades, scaffolding, sashes, exterior walls, interior walls, roofs, interior fittings, piping, chairs, desks, beds, sofas, cabinets. (A17-6) A connecting part of A15 that is applied to any one of the following: syringes, catheters, medical equipment, stands, jigs, blades, scaffolding, sashes, exterior walls, interior walls, roofs, interior fittings, piping, chairs, desks, beds, sofas, cabinets.Capacitors, dryers, fishing tackle (reels), musical instruments, microwave ovens, air conditioners, electric fans, computers, forklifts, tractors, excavators, bulldozers, robotic arms, flanges, caterpillar tracks, hydraulic cylinders, presses, suspensions, pedals, handlebars, guardrails, pipelines, engine blocks, transmissions, pantographs, fences, handrails, landing gear, railway rails, traffic lights, electronic signboards, railroad crossings, propeller shafts, ducts, ventilation fans, suitcases, attaché cases, stepladders, inductors, aluminum trays, bathtubs, support frames, cooling layers, distributors, combiners, in-flight leads, robotic arms, mechanical arms, housings, capsules, valves, detectors, missiles.

[0066] In the present invention, the following aspects can be adopted with regard to "play." While the following aspects are inherently or implicitly included in the present invention, they are described below for clarity. In the embodiments described below and the above description, the play is provided (I) using a member such as a key. However, (II) it may be provided by a fitting shape, or (III) it may be a combination of the aspects in (I) and (II) above. In the following description, it is assumed that, between the output shaft and the pin portion, member A on the output shaft side and member B on the pin portion side are adjacent to each other, and play is provided between member A and member B. Note that members A and B are not particularly limited. Furthermore, the configuration from the output shaft to the pin is not particularly limited, and may be output shaft-holder-collet-tool-pin, output shaft-holder-tool-pin, or output shaft-collet-tool-pin. The tool and pin may be integrated. The collet and holder may be integrated. The following example is applicable to any of these aspects. (I) Play provided using a connecting member such as a key. In this case, the connecting member is provided between members A and B. Members A and B may be located upstream (e.g., the output shaft and holder), in the middle (e.g., the holder and tool), or downstream (e.g., the tool and pin). Members such as a holder, collet, or tool may be divided between the output shaft side and the pin side, and a connecting member may be provided between these members to provide play. Furthermore, although a key is used as the connecting member in the embodiments described below and the above description, a pin or a bolt may also be used. The key is provided between the inner diameter side member and the outer diameter side member along the axial direction of the output shaft. That is, keyways are formed in each of the inner diameter side and outer diameter side members, and keys smaller than the keyways are provided in these keyways to provide play. The key is not particularly limited, and examples include parallel keys with a quadrangular (rectangular or square) cross section, wedge keys (triangular keys) tapered so that one end becomes thinner in the radial direction, crescent keys with a crescent-shaped cross section, round keys with a cylindrical cross section, oval keys, polygonal keys with pentagons or more, diamond keys, and other irregularly shaped keys (for example, T-shaped keys, fan-shaped keys), etc.The shape along the axial direction is not particularly limited, and examples include a straight key with a constant cross-sectional shape in the axial direction, a stepped key with a cross-sectional shape that changes stepwise in the axial direction, and a tapered key with a cross-sectional shape that changes gradually in the axial direction. Furthermore, a spherical body may be used as a connecting member instead of or in addition to a key. Multiple spherical bodies may be arranged side by side in a keyway (ball spline). A dimensional difference between the key and the keyway is provided in at least one of the radial, circumferential, and axial directions. This provides play that allows the pin portion to vibrate in that direction. The pin or bolt is provided so as to pass through both the inner diameter side member and the outer diameter side member along the radial direction of the output shaft. For example, play can be provided by forming a hole in one of the outer diameter side or inner diameter side member with a diameter larger than the diameter of the pin or bolt, and then installing the pin or bolt in the hole along the radial direction of the output shaft. A dimensional difference between the pin or bolt and the hole is provided in at least one of the radial, circumferential, and axial directions. This creates play that allows the pin portion to vibrate in that direction. (II) Play created by a fitting shape (spline): As with (I) above, the fit in this case may be located on any of the upstream, intermediate, and downstream sides. A member such as a holder, collet, or tool may be divided between the output shaft side and the pin portion side, and a fit may be formed between these members, thereby creating play. The spline may be provided over the entire circumferential direction, or may be provided over a portion of the circumferential direction. The spline shape is not particularly limited, and examples include a square spline (square groove), a round spline (round groove), a square spline (V groove), a sawtooth spline, an involute spline, and an involute serration. A dimensional difference between these fits is created in at least one of the radial, circumferential, and axial directions. This creates play that allows the pin portion to vibrate in that direction. (III) Play created by a combination of the above aspects (I) and (II): Play may be created by a combination of a connecting member and a fit. The play may be formed by any combination of the upstream side, the middle side, and the downstream side. Furthermore, the play may be formed by any combination of these.The play may be provided in multiple places.

[0067] According to the present invention, it is possible to provide a friction stir rotating member, a robot-type joining device, and a joined component that enable high-strength joining while suppressing the occurrence of joining defects.

[0068] FIG. 1( a) is a cross-sectional view schematically showing a friction stirring rotating member according to a first embodiment, and FIG. 1( b) is a cross-sectional view taken along line A-A thereof. FIG. 2( a) is a cross-sectional view schematically showing a pin portion and its vicinity of the friction stirring rotating member shown in FIG. 1( a), and FIG. 2( b) is a cross-sectional view schematically showing a pin portion and its vicinity of a rotary tool according to a comparative example. FIGS. 3( a) to 3( t) are cross-sectional views schematically showing friction stirring rotating members according to modified examples. FIG. 4( a) is a cross-sectional view schematically showing a friction stirring rotating member according to a second embodiment, and FIG. 4( b) is a perspective view schematically showing a friction stirring rotating member according to the modified example. FIG. 5( a) is a cross-sectional view schematically showing a friction stirring rotating member according to a third embodiment, and FIGS. 5( b) and 5( c) are perspective views schematically showing friction stirring rotating members according to the modified examples. FIG. 6( a) is a side view schematically showing a robot-type welding apparatus according to a fourth embodiment, and FIG. 6( b) is a partially enlarged view thereof.

[0069] First Embodiment FIG. 1( a) is a cross-sectional view schematically illustrating a friction stirring rotating member 1 according to a first embodiment. FIG. 1( b) is a cross-sectional view taken along line A-A. In the figure, H, C, and T represent a holder, a collet, and a tool, respectively. AD, CD, and RD represent the axial direction, the circumferential direction, and the radial direction, respectively. These symbols may be omitted in other drawings, but are interpreted in the same manner as in this figure. In addition, in each figure, when adjacent members in the friction stirring rotating member 1 are hatched identically, this indicates that the members are fixed to each other. On the other hand, when different members are hatched differently, this indicates that the members are not fixed to each other. In addition, in each figure, the same components are designated by the same symbols.

[0070] The friction stirring rotating member 1 is provided in a joining device 3. The joining device 3 is a device that performs friction stir welding of workpieces 2. The joining device 3 has a drive mechanism 4. The friction stirring rotating member 1 is detachably attached to an output shaft 5 of the drive mechanism 4. The friction stirring rotating member 1 rotates together with the output shaft 5 so as not to be displaced relative to the output shaft 5.

[0071] The friction stirring rotating member 1 includes a metallic rotating shaft portion 10 and a metallic tip portion 20. The rotating shaft portion 10 corresponds to the holder H. The rotating shaft portion 10 has a generally cylindrical shape extending in the axial direction AD. The upper surface side of the rotating shaft portion 10 is fixed to the output shaft 5. The rotating shaft portion 10 has a bottomed hole on the lower surface of the rotating shaft portion 10 for receiving the tip portion 20. The bottomed hole is open downward. The tip portion 20 is provided within the bottomed hole.

[0072] The tip portion 20 has a pin portion 21 and a base end portion 22 provided on the base end side of the pin portion 21. The pin portion 21 corresponds to the tool T. The base end portion 22 corresponds to the collet C. The base end portion 22 has a generally cylindrical shape extending in the axial direction AD. The base end portion 22 has a bottomed hole on its underside for receiving the pin portion 21. The bottomed hole opens downward. The pin portion 21 is provided within the bottomed hole. The pin portion 21 is fixed to the base end portion 22 so as not to be displaced relative to the base end portion 22. The tip of the pin portion 21 is inserted into the workpiece 2 during friction stir welding, as shown in FIG. 1( a). In the figure, PF schematically indicates a plastic flow portion of the workpiece 2 during friction stir welding.

[0073] As shown in FIG. 1B , a plurality of grooves 25 are formed on the outer peripheral surface of the tip portion 20 at intervals in the circumferential direction CD. As shown in FIG. 1A , the grooves 25 are formed to extend in the axial direction AD. A rod-shaped metal fitting key 30 is provided in each groove 25. The inner portion of the fitting key 30 in the radial direction RD is recessed into the groove 25. The outer portion of the fitting key 30 in the radial direction RD is exposed outside the groove 25 in the radial direction RD. Grooves 15 are formed on the inner peripheral surface of the rotating shaft portion 10 at positions corresponding to the exposed portions of each fitting key 30. The length of the groove 15 in the circumferential direction CD is greater than the length of the fitting key 30 in the circumferential direction CD. Therefore, a play CP in the circumferential direction CD is generated within the groove 15. The play CP is provided between the rotating shaft portion 10 and the tip portion 20. The rotating shaft portion 10 is fixed to the output shaft 5, and the tip portion 20 includes a pin portion 21. Therefore, play CP is provided between the output shaft 5 and the pin portion 21. The play CP is a gap or substantially a gap. The pin portion 21 is free or substantially free relative to the output shaft 5 within the range of the play CP. As shown in FIG. 1(b), the tip portion 20 is configured such that, due to the play CP, vibration CV is generated in the circumferential direction CD with respect to the rotating shaft portion 10 during friction stirring. The fitting keys 30 function as keys for transmitting rotational power from the drive mechanism from the rotating shaft 10 to the collet C.

[0074] Furthermore, the friction stirring rotating member 1 has a play AP in the axial direction AD between the rotating shaft portion 10 and the tip portion 20. In other words, the play AP is provided between the output shaft 5 and the pin portion 21. The play AP is a gap or a substantial gap. The pin portion 21 is free or substantially free with respect to the output shaft 5 within the range of the play AP. As shown in FIG. 1( a), the pin portion 21 is configured such that, due to the play AP, vibration AV is generated in the axial direction AD with respect to the output shaft 5 during friction stirring.

[0075] FIG. 2(a) is a cross-sectional view that schematically shows the pin portion 21 and its vicinity of the friction stirring rotating member 1 shown in FIG. 1(a).

[0076] The vibrations AV and CV of the pin portion 21 have a larger amplitude and / or frequency than those of the output shaft 5 (see FIG. 1(a)). The two-dot chain line in FIG. 2(a) shows the pin portion 21 when the vibrations AV and CV are occurring within the plastic flow portion PF.

[0077] Region Q is the region within the workpieces 2 that is affected by the vibrations AV and CV of the pin portion 21. That is, in region Q, the rotation of the pin portion 21 causes plastic flow in the workpieces 2. The pin portion 21 then comes into contact with the workpieces 2, which are undergoing plastic flow, within the range of the play AP and CP. The pin portion 21 is free or substantially free within the range of the play AP and CP. Therefore, passive vibrations AV and CV are generated in the pin portion 21. Because the vibrations AV and CV of the pin portion 21 are passive, they are not only unlikely to interfere with the plastic flow of the workpieces 2, but can also synchronize with and amplify the plastic flow.

[0078] The pin portion 21 has a surface contact portion 24 at a height where it comes into contact with the surface of the workpiece 2. The ratio (diameter SD / diameter PD) of the diameter SD of the surface contact portion 24 to the diameter PD of the pin portion 21 located directly below the surface contact portion 24 (the pin portion 21 that is closer to the tip of the surface contact portion 24 and adjacent to the surface contact portion 24) is 1.8 or less. As a result, the pin portion 21 has a shoulder 23 that is narrow enough to satisfy the ratio (diameter SD / diameter PD) ≦ 1.8.

[0079] Region P is a region near the surface of the workpieces 2. The pin portion 21 has a narrow shoulder 23, which makes it less likely that the shoulder 23 will impede plastic flow. The effect of the vibrations AV and CV of the pin portion 21 (the effect of not impeding plastic flow and amplifying it) can be more effectively achieved. Because the width of the shoulder 23 is small, the amount of heat generated during friction stirring is reduced, but the effect of the vibrations AV and CV of the pin portion 21 makes it possible to achieve effective plastic flow. As a result, friction stir welding can be performed at a lower temperature. In other words, because the width of the shoulder 23 is small, the shoulder 23 is less likely to impede plastic flow, and more amplified plastic flow can be achieved in region P.

[0080] 2B is a cross-sectional view schematically showing a pin portion and its vicinity of a rotary tool 1′ according to a comparative example (prior art). The techniques disclosed in Patent Documents 1 to 3 correspond to this comparative example (prior art).

[0081] During friction stirring, the rotary tool 1' is biased downward by an elastic member (not shown). In the figure, F represents a biasing force. The biasing force F presses the rotary tool 1' against the workpieces 2', maintaining a constant insertion amount of the rotary tool 1' into the workpieces 2' within the plastic flow region PF'. The pin portion 21' does not generate vibrations AV and CV as shown in FIG. 2(a). Region Q' corresponds to region Q in FIG. 2(a). In region Q', even though the workpieces 2' undergo plastic flow around the pin portion 21', the pin portion 21' is biased downward by the biasing force F and remains in its position. As a result, the stationary pin portion 21' may hinder the plastic flow of the workpieces 2. Furthermore, the stationary pin portion 21' does not have the effect of amplifying the plastic flow of the workpieces 2.

[0082] In the rotary tool 1', the ratio (diameter SD' / PD') is 2 or more. The pin portion 21' has a wide shoulder 23'. In addition, the shoulder 23' is urged downward by the urging force F and pressed against the workpieces 2'. Therefore, in the region P', the shoulder 23' hinders plastic flow. Furthermore, because the width of the shoulder 23' is large, a large amount of heat is generated during friction stir welding, making it difficult to perform friction stir welding at low temperatures.

[0083] Figures 3(a) to 3(t) are schematic cross-sectional views of friction stirring rotating members 1 according to modified examples. The letters H, C, and T in Figures 3(a), 3(s), and 3(t) indicate a holder, a collet, and a tool, respectively. For convenience, the letters H, C, and T are omitted in Figures 3(b) to 3(r), but are the same as in Figures 3(a), 3(s), and 3(t).

[0084] [FIG. 3(a)] The frictional stirring rotating member 1 shown in FIG. 3(a) corresponds to the tool T as a whole, with the rotating shaft portion 10 corresponding to a part of the tool T and the tip portion 20 corresponding to a part of the tool T. The tip portion 20 has an integrally formed base end side portion 22 and pin portion 21. The tip portion 20 is attached to the rotating shaft portion 10 by being inserted into a bottomed hole provided on the underside of the rotating shaft portion 10. The underside of the rotating shaft portion 10 forms a shoulder 23. As shown in FIGS. 1(a) and 1(b), a fitting key 30 is provided between the rotating shaft portion 10 and the tip portion 20. As a result, the frictional stirring rotating member 1 has play AP and CP between the rotating shaft portion 10 and the tip portion 20. The frictional stirring rotating member 1 is attached to a collet C. A holder H and a collet C are fixedly provided on the output shaft 5, and the friction stirring rotating member 1 is provided on the output shaft 5 via the holder H and the collet C.

[0085] [Fig. 3(b)] The friction stirring rotating member 1 shown in Fig. 3(b) corresponds to the collet C and the tool T, the rotating shaft portion 10 corresponds to the collet C and a part of the tool T, and the tip portion 20 corresponds to a part of the tool T. The friction stirring rotating member 1 is attached to the output shaft 5 via a holder H. Except for this point, the embodiment in Fig. 3(b) is the same as Fig. 3(a).

[0086] [Fig. 3(c)] The friction stirring rotating member 1 shown in Fig. 3(c) corresponds to the holder H, collet C, and tool T, the rotating shaft portion 10 corresponds to the holder H, collet C, and part of the tool T, and the tip portion 20 corresponds to part of the tool T. The friction stirring rotating member 1 is provided on an output shaft 5. Except for this point, the embodiment in Fig. 3(c) is the same as Fig. 3(a) and Fig. 3(b).

[0087] [FIG. 3(d)] The frictional stirring rotating member 1 shown in FIG. 3(d) has a rotating shaft 10, an intermediate body 40, and a tip portion 20. The frictional stirring rotating member 1 corresponds to the collet C and the tool T. The rotating shaft 10 corresponds to the collet C. The intermediate body 40 corresponds to a part of the tool T. The tip portion 20 corresponds to a part of the tool T. The tip portion 20 is attached to the intermediate body 40 by being inserted into a bottomed hole provided on the underside of the approximately cylindrical intermediate body 40. The underside of the intermediate body 40 forms a shoulder 23. A fitting key 30 is provided between the intermediate body 40 and the tip portion 20. However, in the example shown in FIG. 3(d), the fitting key 30 provides play CP but not play AP. The tip portion 20 can vibrate in the circumferential direction CD (see FIG. 1) relative to the intermediate body 40. The intermediate body 40 is attached to the rotating shaft portion 10 by being inserted into a bottomed hole provided on the underside of the rotating shaft portion 10. This provides play AP between the rotating shaft portion 10 and the intermediate body 40. The intermediate body 40 is vibrable in the axial direction AD (see FIG. 1 ) relative to the rotating shaft portion 10. In this way, the play AP, CP provided between the rotating shaft portion 10 and the tip portion 20 does not necessarily have to be formed by the rotating shaft portion 10 and the tip portion 20. An intermediate body 40 that can be individually displaced relative to each of the rotating shaft portion 10 and the tip portion 20 may be interposed between the rotating shaft portion 10 and the tip portion 20. In this way, the friction stirring rotating member 1 as a whole has play AP, CP between the rotating shaft portion 10 and the tip portion 20.

[0088] [Fig. 3(e)] The friction stirring rotating member 1 shown in Fig. 3(e) has a rotating shaft portion 10, an intermediate body 40, and a tip portion 20, similar to Fig. 3(d). The friction stirring rotating member 1 corresponds to the holder H, the collet C, and the tool T. The rotating shaft portion 10 corresponds to the holder H. The intermediate body 40 corresponds to the collet C and part of the tool T. The tip portion 20 corresponds to part of the tool T. In the embodiment of Fig. 3(e), the position of the play AP differs from that of Fig. 3(d).

[0089] [Fig. 3(f)] In the embodiment of Fig. 3(f), the friction stirring rotating member 1 corresponds to the holder H, the collet C, and the tool T. The rotating shaft portion 10 corresponds to the holder H. The intermediate body 40 corresponds to the collet C. The tip portion 20 corresponds to the tool T. A fitting key 30 is provided between the intermediate body 40 and the tip portion 20, thereby providing a play CP between the intermediate body 40 and the tip portion 20. A play AP is provided between the rotating shaft portion 10 and the intermediate body 40.

[0090] [Fig. 3(g)] In the embodiment of Fig. 3(g), unlike Fig. 3(f), a fitting key 30 is provided between the rotating shaft portion 10 and the intermediate body 40, thereby providing play CP between the rotating shaft portion 10 and the intermediate body 40. Play AP is provided between the intermediate body 40 and the tip portion 20.

[0091] [Fig. 3(h)] In the embodiment of Fig. 3(h), the width of the shoulder 23 is wider than that of Fig. 1. The ratio is 2 or more. Because the shoulder 23 is integral with the pin portion 21, the shoulder 23 also generates vibrations similar to those of the pin portion 21. Therefore, even if the width of the shoulder 23 is wide, it is difficult to hinder the plastic flow of the workpieces 2, and it is possible to amplify the plastic flow. In this respect, the embodiment of Fig. 3(h) differs from the comparative example shown in Fig. 2(b). As mentioned above, the shoulder 23 may be separate from the pin portion 21 and configured not to rotate together with the pin portion 21.

[0092] [FIGS. 3(i) and 3(j)] The shapes of the tips of the pin portions 21 in the embodiments of FIG. 3(i) and FIG. 3(j) are different from those in FIG. 1. The tips of the pin portions 21 in FIG. 1 have a tapered truncated cone shape (a truncated cone shape in which the tip side is thinner than the base end side), whereas the tips of the pin portions 21 in FIG. 3(i) have a tapered inverted truncated cone shape (a truncated cone shape in which the tip side is thicker than the base end side). The tips of the pin portions 21 in FIG. 3(j) have a cylindrical shape. As such, the shape of the tips of the pin portions 21 is not particularly limited. Various shapes can be adopted as the shape of the pin portions 21.

[0093] [Fig. 3(k)] In the embodiment of Fig. 3(k), the ratio is 1.0, and the friction stir rotating member 1 does not have a shoulder. Because this friction stir rotating member 1 does not have a rotating shoulder, friction stir welding can be achieved at a lower temperature.

[0094] [Figures 3(l) and 3(m)] In the embodiment of Figure 3(l), unlike Figure 1, the frictional stirring rotating member 1 has only play AP in the axial direction AD (see Figure 1). In addition, in the embodiment of Figure 3(m), the frictional stirring rotating member 1 has only play CP in the circumferential direction CD (see Figure 1). In this way, the frictional stirring rotating member 1 may have play in only one direction among the axial direction AD, the circumferential direction CD, and the radial direction RD.

[0095] [FIG. 3(n)] In the embodiment of FIG. 3(n), the friction stirring rotating member 1 corresponds to the collet C and the tool T. The rotating shaft portion 10 corresponds to the collet C. The tip portion 20 corresponds to the tool T. The tip portion 20 has a pin portion 21 and a base end portion 22 that are integrally formed with each other. The tip portion 20 is attached to the rotating shaft portion 10 by being loosely fitted into a large-diameter, bottomed hole 17 provided on the underside of the rotating shaft portion 10. Because the diameter of the large-diameter, bottomed hole 17 is larger than the diameter of the base end portion 22, play RP in the radial direction RD (see FIG. 1) is provided around the base end portion 22. A fixed key 31 is fixed to the outer surface of the base end portion 22. A lateral through-hole 16 is provided in the rotating shaft portion 10 at a position corresponding to the fixed key 31. The lateral through-hole 16 provides play CP as well as play RP. That is, the tip portion 20 has play CP and play RP between it and the rotating shaft portion 10. The tip portion 20 is vibrable relative to the rotating shaft portion 10 in the circumferential direction CD and the radial direction RD.

[0096] [FIG. 3(o)] In the embodiment shown in FIG. 3(o), the friction stirring rotating member 1 has a rotating shaft portion 10, an intermediate body 40, and a tip portion 20. The friction stirring rotating member 1 corresponds to the holder H, collet C, and tool T. The rotating shaft portion 10 corresponds to the holder H. The intermediate body 40 corresponds to the collet C. The tip portion 20 corresponds to the tool T. The tip portion 20 has a pin portion 21 and a base end portion 22 that are integrally formed with each other. The tip portion 20 is attached to the intermediate body 40 by loosely fitting into a large-diameter, bottomed hole 17 provided on the underside of the intermediate body 40. Because the diameter of the large-diameter, bottomed hole 17 is larger than the diameter of the base end portion 22, play RP in the radial direction RD (see FIG. 1) is provided around the periphery of the base end portion 22. A fixing key 31 is fixed to the outer surface of the base end portion 22. A lateral through-hole 16 is provided in the intermediate body 40 at a position corresponding to the fixed key 31. The lateral through-hole 16 provides a play CP as well as a play RP. That is, the tip portion 20 has a play CP and a play RP between it and the intermediate body 40. The tip portion 20 can vibrate in the circumferential direction CD and the radial direction RD relative to the intermediate body 40. The intermediate body 40 is attached to the rotating shaft portion 10 by being inserted into a bottomed hole provided on the underside of the rotating shaft portion 10. This provides a play AP between the rotating shaft portion 10 and the intermediate body 40. The intermediate body 40 can vibrate in the axial direction AD (see FIG. 1 ) relative to the rotating shaft portion 10. As described above, the friction stirring rotating member 1 has play AP, CP, and RP between the rotating shaft portion 10 and the tip portion 20. Therefore, the tip portion 20 can vibrate in all directions, including the axial direction AD, the circumferential direction CD, and the radial direction RD, relative to the rotating shaft portion 10.

[0097] [Fig. 3(p)] In the embodiment of Fig. 3(p), unlike the embodiment of Fig. 1, the play AP, CP are not gaps, but are filled with a liquid 41 (e.g., lubricating oil). Such a friction-stirring rotating member 1 can also achieve the vibration of the pin portion 21 as described using Fig. 2(a), and is clearly different from the embodiment of Fig. 2(b). In other words, the play AP, CP are essentially gaps. The tip portion 20 is essentially free within the range of the play AP, CP.

[0098] [Fig. 3(q)] In the embodiment of Fig. 3(q), compared to the embodiment of Fig. 1, an elastic body 42 (e.g., an O-ring) is provided in the play AP between the rotating shaft portion 10 and the tip portion 20. Such a friction stirring rotating member 1 can also achieve vibration of the pin portion 21 as described using Fig. 2(a), and is clearly different from the embodiment of Fig. 2(b). In other words, the play AP, CP are essentially gaps. The tip portion 20 is essentially free within the range of the play AP, CP.

[0099] In the above example, a description has been given of a case in which the friction stirring rotating member 1 has a rotating shaft portion 10 and a tip portion 20, there is play between the rotating shaft portion 10 and the tip portion 20, and the tip portion 20 includes a pin portion 21. However, the friction stirring rotating member 1 is not limited to the above example, and the following aspects can be adopted, for example.

[0100] [Fig. 3(r)] In the embodiment of Fig. 3(r), the frictional stirring rotating member 1 corresponds to the collet C and the tool T. The frictional stirring rotating member 1 is configured as a single unit as a whole, and has a pin portion 21 and a shoulder 23. The frictional stirring rotating member 1 is configured to be attached to a holder H, thereby generating play AP between the frictional stirring rotating member 1 and the holder H. Due to the play AP, the frictional stirring rotating member 1 including the pin portion 21 vibrates in the axial direction AD relative to the output shaft 5 during frictional stirring.

[0101] [FIG. 3(s)] In the embodiment of FIG. 3(s), the frictional stirring rotating member 1 corresponds to the holder H. The frictional stirring rotating member 1 has a bottomed hole on its underside into which the collet C and tool T are inserted. The collet C and tool T are detachably attached to the frictional stirring rotating member 1 by inserting the collet C and tool T into the bottomed hole. The frictional stirring rotating member 1 does not have a pin portion. The pin portion is included in the tool T. The frictional stirring rotating member 1 has a bottomed hole on its upper surface for receiving an output shaft 5. The output shaft 5 is inserted into the bottomed hole, and the frictional stirring rotating member 1 is attached to the output shaft 5. The frictional stirring rotating member 1 is configured to generate play AP between the output shaft 5 and the frictional stirring rotating member 1 when attached to the output shaft 5. As a result, play AP is generated between the output shaft 5 and the pin portion of the tool T during frictional stirring. The play AP allows the pin portion to vibrate relative to the output shaft 5.

[0102] [FIG. 3(t)] In the embodiment shown in FIG. 3(t), the frictional stirring rotating member 1 has a rotating shaft portion 10 and a tip portion 20. The frictional stirring rotating member 1 corresponds to the holder H. The rotating shaft portion 10 is the upper portion of the holder H and is attached to the output shaft 5. The tip portion 20 is the lower portion of the holder H and is configured to rotate by rotation transmitted from the rotating shaft portion 10 and is located more distal than the rotating shaft portion 10. The tip portion 20 is configured to detachably attach a collet C and a tool T. That is, the tip portion 20 does not have a pin portion, but has a base end portion 22 configured to detachably attach a pin portion. Plays AP and CP are provided between the rotating shaft portion 10 and the tip portion 20 to allow vibration of the pin portion relative to the rotating shaft portion 10. Note that the frictional stirring rotating member 1 is not limited to the above example. The friction stirring rotating member 1 only needs to be configured so as to create play between the output shaft 5 and the pin portion 21 when attached to the output shaft 5, and does not necessarily have to be based on the distinction between the parts of the holder H, collet C, and tool T.

[0103] 1( a) and 1(b) , the welding device 3 according to the first embodiment is a welding device 3 including a friction stirring rotating member 1. The welding device 3 includes a drive mechanism 4 including an output shaft 5 and a pin portion 21. The pin portion 21 has play AP and CP between the output shaft 5 and the pin portion 21, which enable vibration AV and CV of the pin portion 21 relative to the output shaft 5. Due to the play AP and CP, the welding device 3 has vibrations AV and CV of the pin portion 21 during friction stirring that have a larger amplitude and / or frequency than the vibration (base vibration) of the output shaft 5. While the welding device 3 of this embodiment includes a friction stirring rotating member 1 having play AP and CP, the welding device 3 does not necessarily need to include a friction stirring rotating member 1 as long as there is play between the output shaft 5 and the pin portion 21.

[0104] 1( a) and 1(b) , the welding method according to the first embodiment can be performed by the above-described welding apparatus 3. In this welding method, the pin portion 21 is rotated by rotation output from the drive mechanism 4, and the pin portion 21 is inserted into the workpieces 2, thereby performing friction stir welding of the workpieces 2. In this welding method, friction stir welding is performed on the workpieces 2 in a state in which vibrations having amplitudes and / or frequencies greater than base vibrations transmitted from the drive mechanism 4 to the pin portion 21 by the rotation of the drive mechanism 4 are passively generated in the pin portion 21 by contact with the workpieces 2 that are undergoing plastic flow during friction stirring.

[0105] In a welding method according to another embodiment, the pin portion 21 is inserted into the workpieces 2 while being rotated by rotation output from the drive mechanism 4, thereby performing friction stir welding of the workpieces 2. In this welding method, friction stir welding is performed on the workpieces 2 while feedback controlling the drive mechanism 4 so that the output of the drive mechanism 4 changes in synchronization with or following the rotational fluctuation of the pin portion 21 that occurs passively due to contact with the workpieces 2 that undergo plastic flow. The rotational fluctuation can be detected by a conventionally known rotational speed sensor such as a resolver or encoder.

[0106] Furthermore, the numerical values, materials, structures, shapes, etc. described in the above-described embodiments are merely examples, and different numerical values, materials, structures, shapes, etc. may be used as necessary. Furthermore, in the above-described embodiments, the friction stirring rotating member 1 is located on top, the workpieces 2 are located on the bottom, and the friction stirring rotating member 1 and the workpieces 2 face each other in the vertical direction. That is, the axial direction is the same as the vertical direction. However, the axial direction does not necessarily have to be the same as the vertical direction. The axial direction is not particularly limited and may be, for example, horizontal. Furthermore, when the axial direction is the vertical direction, the friction stirring rotating member may be located on the bottom and the workpieces to be welded may be located on the top. Furthermore, the axial direction does not necessarily have to be fixed. When a joining device is configured by installing a friction stirring rotating member in the above-described portable device, the axial direction may change during operation.

[0107] 4(a) is a cross-sectional view schematically showing a friction stirring rotating member according to a second embodiment. In the second embodiment, unless otherwise specified, the same reference numerals as in the first embodiment are used for components corresponding to those in the first embodiment, and the description thereof will be omitted.

[0108] The friction stirring rotating member 1 according to the second embodiment has a drop-off prevention structure 50 that prevents the pin portion 21 from dropping off from the output shaft 5. The drop-off prevention structure 50 is configured to prevent the tool T, including the pin portion 21, from dropping off together with the collet C from the rotating shaft 10. The drop-off prevention structure 50 includes a drop-off prevention member 50A having a pin portion insertion hole 50B formed therein, a drop-off prevention member mounting member 10C, and a step T1, which will be described later. The drop-off prevention member 50A has a flat plate shape. The drop-off prevention member 50A is fixed to the rotating shaft 10 by the drop-off prevention member mounting member 10C. The pin portion insertion hole 50B is smaller than at least the maximum diameter of the collet C and has a size that allows the pin portion 21 to be exposed to the outside. The drop-off prevention structure 50 is configured such that the step T1, formed by the difference in outer diameter between the collet C and the tool T, engages with the pin portion insertion hole 50B, thereby preventing the tool T from dropping off. That is, the fall-off prevention structure 50 ensures that the tool T is exposed to the outside through the pin insertion hole 50B, allowing the pin 21 to be positioned at the intended joining position of the workpieces 2 (e.g., the intended joining line position of a pair of butted workpieces 2, 2), while preventing the tool T from falling off due to the provision of clearance CP. Such fall-off of the tool T is primarily due to gravity, which is the weight of the tool T, including the pin 21. This problem tends to become more pronounced when the tool T is configured to be detachable and replaceable. Furthermore, from the perspective of joining quality, it is preferable to provide clearance AP between the pin 21 and the output shaft 5 to the extent that the tool T, including the pin 21, can fall off together with the collet C from the rotating shaft 10, rather than providing clearance AP between the pin 21 and the output shaft 5 to the extent that the pin 21 does not fall off. However, as the clearance AP increases, the risk of the tool T falling off increases. Such a risk may be reduced by filling the slack AP portion with a fire-resistant hydraulic oil such as a water-glycol-based hydraulic oil, depending on the viscosity of the hydraulic oil; however, in this embodiment, the weight of the collet C and tool T, which are integrally joined, is relatively heavy, and the viscosity of the hydraulic oil alone is insufficient to support that weight.Furthermore, when the friction stirring rotating member 1 is installed in a robot-type welding apparatus as described below, centrifugal force and inertial force are applied to the friction stirring rotating member 1 when the friction stirring rotating member 1 is rotated, pivoted, and / or moved by a robot arm, further increasing the likelihood of the tool T falling off. However, the anti-fall-off structure 50 can prevent the tool T from falling off. Note that the structure of the anti-fall-off structure 50 is not limited to this embodiment. The anti-fall-off member mounting member 10C is a screw, but is not particularly limited thereto. Furthermore, the anti-fall-off member 50A may have a cap shape with a threaded inner periphery, while a corresponding threaded outer periphery of the rotating shaft 10 may have a corresponding threaded outer periphery. This allows the anti-fall-off member 50A to be fixed to the rotating shaft 10 without using the anti-fall-off member mounting member 10C. This embodiment will be described in the following modified example. Furthermore, the provision of the play AP as in the present invention has the advantage of facilitating the replacement of the tool T. In particular, when a general user or an operator unfamiliar with the handling replaces the tool T, the tool T can be easily grasped and removed by hand and replaced with a new tool without the need for a dedicated tool replacement device.

[0109] <Modification of the Second Embodiment> Figure 4(b) is a perspective view schematically illustrating a friction stirring rotating member 1 according to a modification of the second embodiment. In this modification, unless otherwise specified, components corresponding to those in the above-described embodiment are denoted by the same reference numerals as in the above-described embodiment, and their description is omitted. In the friction stirring rotating member 1 according to this modification, the collet C and tool T, which are integrally formed with each other, are inserted together with the fitting key 30 into a bottomed hole formed in the rotary shaft portion 10 from the distal end opening 10A of the rotary shaft portion 10, thereby mounting the collet C and tool T in the distal end opening 10A of the rotary shaft portion 10. The drop-off prevention structure 50 includes a drop-off prevention member 50A and a step T1. The drop-off prevention member 50A is configured such that the diameter r of the pin insertion hole 50B formed in the drop-off prevention member 50A and the outer shape R of the collet C satisfy the relationship r<R. The tip of the tool T, together with the collet C integrally formed with the tool T, is prevented from sinking into the rotating shaft portion 10, and the tip of the tool T is exposed to the outside through the pin insertion hole 50B. As described above, the stopper member 50A and the rotating shaft portion 10 are fixed to each other by their respective thread grooves, which can prevent the stopper member 50A and the rotating shaft portion 10 from separating during friction stir welding. Note that the structure for fixing the stopper member 50A to the rotating shaft portion 10 is not limited to this example. Furthermore, the tool T is configured so that the outer diameter of the tool T is smaller than the diameter r of the pin insertion hole 50B. This allows the tool T to be separated from the collet C and removed from the stopper member 50A through the pin insertion hole 50B by gripping and rotating the tool T attached to the collet C. Another tool T can also be attached to the collet C through the pin insertion hole 50B. Therefore, only the tool T can be replaced. In this embodiment, the tool T and the collet C can be separated, but the tool T and the collet C may also be configured as an integral unit that cannot be separated. In this case, the fall-off prevention member 50A is removed from the rotating shaft portion 10, and the collet C and the tool T are replaced. The frictional stirring rotating member 1 shown in Figures 4(a) and 4(b) has a tip-insertion type fall-off prevention structure 50 into which the collet C and the tool T are inserted from the tip side, but the frictional stirring rotating member is not limited to these examples.The friction stirring rotary member may have a rear end insertion type dropout prevention structure in which the collet C and tool T are inserted from the rear end side, as shown in FIGS. 5(a) to 5(c).

[0110] Third Embodiment FIG. 5( a) is a cross-sectional view schematically illustrating a friction stirring rotating member 1 according to a third embodiment. In the third embodiment, components corresponding to those in the above-described embodiments are denoted by the same reference numerals as in the above-described embodiments, and their description is omitted unless otherwise specified. The friction stirring rotating member 1 according to the third embodiment includes a fall-off prevention portion 50A' formed integrally with the rotating shaft portion 10, instead of the above-described fall-off prevention member 50A. The fall-off prevention portion 50A' includes a pin insertion hole 50B. A rear hole 10E is formed at the rear end of the rotating shaft portion 10. A tool T and a collet C, which are integrally formed with each other, are inserted through the rear hole 10E together with a fitting key 30. Furthermore, a closing member 100 is provided to close the rear hole 10E from the rear. Corresponding thread grooves are formed in the closing member 100 and the rotating shaft portion 10, and the closing member 100 is fixed to the rotating shaft portion 10 by these thread grooves. This makes it possible to prevent the tool T and collet C from falling off and to keep the tip of the tool T exposed at all times while ensuring the play AP. In this embodiment, the stirring prevention structure 50 includes a falling-off prevention portion 50A′, a step T1, and a closing member 100.

[0111] <Modification of the Third Embodiment> Figures 5(b) and (c) are perspective views schematically illustrating a friction stirring rotating member according to a modification of the third embodiment. In this modification, unless otherwise specified, components corresponding to those in the above-described embodiment are denoted by the same reference numerals as in the above-described embodiment, and their description is omitted. In the friction stirring rotating member 1 according to Figures 5(b) and (c), similar to the friction stirring rotating member 1 according to Figure 5(a), an integrally configured tool T and collet C are inserted into the rear hole 10E from the rear end side, and the rear hole 10E is closed by the closing member 100. The fixing structure of the closing member 100 is not limited to a screw structure. For example, any structure may be employed, such as a forced fit, or drilling a locking screw insertion hole penetrating the outer periphery of the rotating shaft portion 10 and fixing the locking screw with a headless screw.

[0112] Fourth Embodiment FIG. 6( a) is a side view schematically illustrating a robot-type joining apparatus A1 according to a fourth embodiment. FIG. 6( b) is a partially enlarged view illustrating the vicinity of a frictional stirring rotating member 1 provided in the robot-type joining apparatus A1. The robot-type joining apparatus A1 includes a robot arm A2. The robot arm A2 in this embodiment is a multi-joint robot arm having multiple joints. However, the robot arm is not limited to this example and may include at least one joint. The robot arm A2 includes a joining device 3 provided at the distal end of the robot arm A2. The joining device 3 includes an output shaft 5 provided at the distal end of the robot arm A2 and a drive mechanism 4 configured to rotate the output shaft 5. The frictional stirring rotating member 1 is provided at the distal end of the output shaft 5. The frictional stirring rotating member 1 according to each of the above-described embodiments may be employed. In this embodiment, the frictional stirring rotating member 1 is separate from the output shaft 5, and the frictional stirring rotating member 1 is attached to the output shaft 5. However, the robot-type joining apparatus A1 is not limited to this example. The robot-type welding apparatus A1 does not need to include the friction stirring rotating member 1, and it is sufficient that there is play between the output shaft 5 and the pin portion 21. Due to the play, the pin portion 21 vibrates at a greater amplitude and / or frequency than the output shaft 5 during friction stirring. In the robot-type welding apparatus A1 including the friction stirring rotating member 1, the friction stirring rotating member 1 is provided at the tip of the output shaft 5, and the pin portion 21 is provided at the tip of the output shaft 5. A position adjustment mechanism 3a is provided between the robot arm A2 and the output shaft 5. The position adjustment mechanism 3a is configured to adjust the insertion depth of the pin portion 21 into the workpieces 2 placed on the stage A6 in the direction facing the workpieces 2 and the pin portion 21. In this embodiment, the workpieces 2 are placed on the stage A6 so that they are approached by the pin portion 21 from above in the vertical direction, and are fixed to the stage A6 by a fixing mechanism (not shown) such as a jig. However, the manner in which the workpieces 2 are fixed is not limited to this example. The approach direction of the pin portion 21 is not limited to a vertically upward direction, but may be in another direction.The robot arm A2 according to this embodiment is capable of freely moving or operating the friction stirring rotating member 1 in three-dimensional space using a multi-joint structure and a servo motor (not shown). The robot arm A2 has legs A2-2, lower arms A2-3, upper arms A2-4, and wrists A2-5 and A2-6 mounted on a base A2-1. The number of joints is arbitrary. As the number of joints increases, a wider variety of movements becomes possible. In the robot arm A2, a position adjustment mechanism 3a and a joining device 3 are connected in this order to the tip of the wrist A2-6. The position adjustment mechanism 3a includes a position control motor 3a-1 that can rotate forward and backward, a rotating shaft 3a-2 directly connected to the position control motor 3a-1, and a slider 3a-3 attached to the rotating shaft 3a-2. Rotation of the position control motor 3a-1 rotates the rotating shaft 3a-2. The slider 3a-3 is configured to move along the rotation shaft 3a-2 as the rotation shaft 3a-2 rotates. When the position control motor 3a-1 rotates forward, the slider 3a-3 moves toward one end of the rotation shaft 3a-2. When the position control motor 3a-1 rotates reversely, the slider 3a-3 moves toward the other end of the rotation shaft 3a-2. In other words, the slider 3a-3 can reciprocate along the rotation shaft 3a-2. A welding device 3 is provided on the slider 3a-3, and as the slider 3a-3 reciprocates, the welding device 3 can also reciprocate along the rotation shaft 3a-2. The reciprocating movement of the welding device 3 can adjust the insertion depth of the pin portion 21 into the workpieces 2. The drive mechanism 4 includes a drive motor 4a, a first pulley 4b, a rotation transmission belt 4c, and a second pulley 4d. The drive mechanism 4 is configured so that the rotational force output from the drive motor 4a is transmitted to the friction stirring rotating member 1 provided on the tip side of the output shaft 5 via the first pulley 4b, the rotation transmission belt 4c, the second pulley, and the output shaft 5. Furthermore, the robot type joining device A1 is equipped with a control unit A5 (control device). The movement of the joining device 3 by the robot arm A2 and the joining operation of the joining device 3 are controlled by commands from the control unit A5. The control unit A5 is equipped with a memory unit (not shown). The memory unit stores data such as parameters related to the movement of the joining device 3 and the joining operation of the joining device 3.The robot-type joining device A1 may also include a detection unit (not shown) that detects the rotational state of the pin portion 21. The detection unit is not particularly limited as long as it is a sensor that can detect at least one parameter related to the rotational state of the pin portion 21. Examples of such parameters include the rotational speed, rotational angle, and rotational torque. This may allow the above-mentioned feedback control to be performed.

[0113] Friction stirring rotating member: 1 Workpiece to be joined: 2 Joining device: 3 Drive mechanism: 4 Output shaft (of drive mechanism): 5 Rotating shaft portion: 10 Groove: 15 Lateral through-hole: 16 Large diameter bottomed hole: 17 Tip portion: 20 Pin portion: 21 Base end side portion: 22 Shoulder: 23 Surface contact portion: 24 Groove: 25 Fitting key: 30 Fixed key: 31 Intermediate body: 40 Liquid: 41 Elastic body: 42

Claims

1. A friction stirring rotating member provided in a joining device that performs friction stir welding of workpieces, the friction stirring rotating member being provided on an output shaft of a drive mechanism provided in the joining device so as to rotate by rotation output from the drive mechanism, the friction stirring rotating member being configured to generate play between the output shaft and a pin portion that is inserted into the workpieces during friction stirring, which allows the pin portion to vibrate relative to the output shaft.

2. The friction stirring rotating member according to claim 1, further comprising a falling-off prevention structure for preventing the pin portion from falling off the output shaft.

3. The frictional stirring rotating member according to claim 1 or 2, wherein the frictional stirring rotating member comprises a rotating shaft portion provided on the output shaft, and a tip portion configured to rotate by rotation transmitted from the rotating shaft portion and located further tip than the rotating shaft portion, the tip portion having the pin portion and a base end side portion provided on the base end side of the pin portion, or having a base end side portion not having the pin portion but configured to allow the pin portion to be detachably attached, the play is provided between the rotating shaft portion and the tip portion so as to enable vibration of the pin portion relative to the rotating shaft portion, and the frictional stirring rotating member is configured such that, due to the play, vibration of the pin portion during frictional stirring has a larger amplitude and / or frequency than vibration of the rotating shaft portion.

4. A friction stirring rotating member as described in claim 3, wherein the pin portion has a surface contact portion at a height where it contacts the surface of the workpiece, and the ratio of the diameter of the surface contact portion to the diameter of the pin portion adjacent to the surface contact portion closer to the tip than the surface contact portion is 1.8 or less, whereby the pin portion is configured to have a shoulder with a width small enough to satisfy the ratio, or to have no shoulder.

5. The friction stirring rotating member according to any one of claims 1 to 4, wherein the vibration of the pin portion is generated passively by contact with the workpieces undergoing plastic flow within the range of play.

6. The friction stirring rotating member according to any one of claims 1 to 5, wherein the friction stirring rotating member is configured so that vibration of the pin portion occurs in at least one of the axial direction, circumferential direction and radial direction of the pin portion due to the play.

7. The friction stirring rotating member according to any one of claims 1 to 6, wherein the pin portion is configured to be free or substantially free relative to the output shaft within the range of play.

8. The friction stirring rotating member according to any one of claims 1 to 7, wherein the play is a gap or substantially a gap.

9. A robot type joining device which performs friction stir welding of the workpieces, comprising: a robot arm having at least one joint; an output shaft provided at a tip side of the robot arm; a drive mechanism configured to rotate the output shaft; and the friction stir rotating member according to any one of claims 1 to 8 which is provided on the output shaft.

10. A robot-type joining device for friction stir welding of workpieces, comprising: a robot arm having at least one joint; an output shaft provided at the tip of the robot arm; a drive mechanism configured to rotate the output shaft; and a pin portion configured to rotate by rotation transmitted from the drive mechanism and inserted into the workpieces during friction stirring, wherein the pin portion is configured to have play between the output shaft and the pin portion so as to enable vibration of the pin portion relative to the output shaft.

11. The robot-type joining device according to claim 10, wherein the pin portion is configured such that, due to the play, the vibration of the pin portion during friction stirring has an amplitude and / or frequency greater than the vibration of the output shaft.

12. A robot-type joining device for friction stir welding of members to be joined, comprising: a robot arm having at least one joint; an output shaft provided at the tip of the robot arm; a drive mechanism configured to rotate the output shaft; a pin portion provided at the tip of the output shaft; a control unit for controlling the drive mechanism so that the pin portion is inserted into the members to be joined while rotating with the rotation output from the drive mechanism, thereby performing friction stir welding of the members to be joined; and a detection unit for detecting the rotation state of the pin portion, wherein the control unit performs feedback control of the drive mechanism based on the rotation state of the pin portion detected by the detection unit so that the output of the drive mechanism changes in synchronization with or following the rotational fluctuation of the pin portion that occurs passively due to contact with the members to be joined that are undergoing plastic flow, while performing friction stir welding on the members to be joined.

13. The robot type joining device according to any one of claims 9 to 12, wherein the robot arm is a multi-joint robot arm having a plurality of joints.

14. A robot type joining device according to any one of claims 9 to 13, wherein the robot arm has a position adjustment mechanism configured to adjust the insertion depth of the pin portion into the workpieces in the opposing direction between the workpieces and the pin portion.

15. A welded part manufactured by friction stir welding using the friction stir rotating member according to any one of claims 1 to 8.

16. The joining part according to claim 15, which is applied to any one of vehicles including automobiles, railway vehicles, aircraft, ships, and rockets.

17. The joining part according to claim 15, which is applied to any one of an electrode part, an air conditioning device, a water-cooled or air-cooled power control unit, a water-cooled or air-cooled battery case, a door panel, a shock absorber, a suspension link, a waveguide, an antenna, a motor cover, a sake brewing tank, a vacuum device part, a sputtering target material, and an embedded heater.

18. The joined part according to any one of claims 15 to 17, which is a part manufactured by friction stir welding a plurality of plate materials of different thicknesses, or a part manufactured by friction stir welding a plurality of members made of different materials.

Images