JP2005238300A - Friction welding device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To inhibit deterioration in joining quality and to improve durability of a friction welding device by preventing eccentricity or warpage of a rotary tool 30, while suppressing the total lengths of a rotary shaft 20 and a screw shaft 10 in their axial directions, when using the friction welding device, in which a part to be joined is softened and joined by pressing the front end part of the rotary tool 30 to the part to be joined while rotating the front end part to generate frictional heat. <P>SOLUTION: The screw shaft 10, which is rotated by a pressure shaft motor 5, is inserted into a hollow part 20b of the rotary shaft 20, to whose front end the rotary tool 30 is attached, and is supported rotatably in relation to a device main body 4 and immovably in the direction of the axis of the rotary shaft. The base end side of the rotary shaft 20 is rotatably held by a slide member 12 engaged with the screw shaft 10, and further the rotary shaft 20 is moved in the direction of the axis of the rotary shaft with the movement of the slide member 12. The driving force of a rotary shaft motor 6 is transmitted to the rotary shaft 20 by a 2nd rotation transmitting means 21. The rotary shaft 20 is rotatably supported by a rotationally supporting member 23. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a friction welding apparatus that superposes a plurality of plate materials and joins the plate materials by plastic flow.

  2. Description of the Related Art Conventionally, a friction welding apparatus is known that presses against a bonded portion while rotating a tip portion of a rotary tool to generate frictional heat and softens the bonded portion to bond. Such a friction welding apparatus has a rotating shaft and a pressing shaft (screw shaft) provided in parallel with a space therebetween. Specifically, the rotary shaft is splined concentrically with the drive shaft of the rotary shaft motor, and a pipe-like support shaft is provided outside the rotary shaft. The tip end side of the rotation shaft is supported rotatably with respect to the support shaft by a bearing provided at the tip of the support shaft. The support shaft is coupled to a nut that is screwed to a screw shaft coupled to the drive shaft of the pressing shaft motor, the pressing shaft is rotated, the nut is advanced and retracted, and the supporting shaft is moved up and down on the axis of the rotating shaft. Thus, the rotating shaft is configured to be rotated by the rotating shaft motor and to be moved up and down by the pressing shaft motor.

  However, in the above-described friction welding apparatus, when the screw shaft is rotated and the support shaft is lowered and the rotation shaft presses the workpiece, the rotation shaft and the screw shaft are provided in parallel with a gap therebetween. A bending moment may occur and play may occur. For this reason, the tool attached to the tip of the rotating shaft may be shaken or the tool may bend, causing the tool to come into contact with the workpiece, deteriorating the bonding quality and reducing the durability of the friction bonding device. There is.

Therefore, for example, the rotation shaft and the screw shaft are provided concentrically and spaced apart from each other in the vertical direction, and are connected to each other by a connecting member. The outer spline formed on the outer peripheral portion of the connecting member is provided on the apparatus main body. There is one in which a spline receiver is fitted (see, for example, Patent Document 1).
Japanese Patent No. 3291491

  However, in the friction welding apparatus as in Patent Document 1, since the rotary shaft and the screw shaft are separated from each other in the rotational axis direction and do not overlap each other in the rotational axis direction, the screw shaft on the upper side. A space for the stroke of the rotary shaft is required between the tip of the rotary shaft and the base end of the rotary shaft on the lower side. For this reason, the total length in the direction of the rotational axis of the friction welding apparatus is long.

  As described above, since the entire length in the direction of the rotation axis is increased, there is a problem in that the rotation shaft is liable to be shaken and the buckling strength of the rotation shaft and the screw shaft is reduced.

  The present invention has been made in view of such points, and the object of the present invention is to devise the configuration of the screw shaft and the rotating shaft, while suppressing the total length in the axial direction of the rotating shaft and the screw shaft, It is to prevent the run-out and deflection of the tool to prevent the deterioration of the bonding quality and improve the durability of the friction bonding apparatus.

  In order to achieve the above object, in the present invention, the screw shaft and the rotation shaft are wrapped in the direction of the rotation axis.

  Specifically, in the rotary tool of the first invention, there is provided a friction welding device that presses against the joined portion while rotating the tip portion of the rotating tool to generate frictional heat, and softens and joins the joined portion. set to target.

  The rotating tool is attached to the distal end, the rotating shaft provided with a hollow portion having an opening at the proximal end, and concentric with the rotating shaft and insertable into the hollow portion of the rotating shaft. A screw shaft that is supported so as to be rotatable and immovable in the direction of the rotation axis; first rotation driving means that drives the screw shaft to rotate through the first rotation transmission means; and a base end side of the rotation shaft And a slide member that is screwed to the screw shaft and supported by the apparatus main body so as to be movable in the direction of the rotation axis, and that moves the rotation axis in the direction of the rotation axis along with the movement, and the rotation Second rotation driving means for rotating the shaft via second rotation transmission means, and a rotation support member for rotatably supporting the rotation shaft are provided.

  According to the above configuration, by inserting the screw shaft into the hollow portion of the rotation shaft, the screw shaft and the rotation shaft are wrapped in the direction of the rotation axis, and the total length of the rotation shaft and the screw shaft in the axial direction can be suppressed. it can. For this reason, it is possible to suppress the entire length of the entire apparatus in the direction of the rotation axis, to prevent the rotation of the rotation shaft from being shaken, and to improve the buckling strength. Further, the screw shaft is rotated, the slide member moves in the direction of the rotation axis, the rotation shaft held by the slide member also moves in the direction of the rotation axis, and the rotation shaft presses the workpiece. Also at this time, since the rotating shaft and the screw shaft are concentric, the applied pressure is transmitted straight to the rotating shaft, so that no bending moment is generated on the rotating shaft and no rattling occurs. For this reason, an excessive load is not applied to the apparatus, and the tool is not shaken or the tool is not bent, so that the tool does not hit the work. Therefore, it is possible to stabilize the bonding quality and improve the durability of the friction bonding apparatus.

  In the second invention, the slide member has a cylindrical shape, and a screw groove is formed on the inner peripheral surface of the base end side, while a first bearing member is provided on the inner peripheral surface of the distal end side. The base end of the rotation shaft is inserted into the distal end side of the slide member and is rotatably held by the first bearing member.

  According to the above configuration, since the rotation shaft is inserted into and supported by the first cylindrical bearing member of the rigid cylindrical slide member, the rotation support of the rotation shaft is stable, and the rotation shaft is fixed on the inner peripheral surface of the slide member. Since the one bearing member and the thread groove are functionally compactly arranged, the entire apparatus can be miniaturized.

  In a third aspect of the invention, the second rotation transmission means includes a rotating cylinder that is spline-coupled to the outer peripheral portion of the rotating shaft, and the rotational force of the second rotation driving means is transmitted to the rotating cylinder, while the rotation support The member includes a second bearing member that rotatably supports the rotating cylinder with respect to the apparatus main body.

  According to the above configuration, the rotary cylinder can have a function of transmitting a rotational force to the rotary shaft and a function of supporting the rotary shaft rotatably on the apparatus main body and preventing the rotation of the rotary shaft. Can be simple.

  In a fourth invention, the apparatus body is provided with a guide rail for guiding the slide member in the axial direction of the rotation shaft.

  According to said structure, since the slide member is guided by the guide rail of an apparatus main body, it can move to a rotating shaft center direction stably. In addition, the structure is simple compared to a structure in which a spline groove is provided on the outer periphery of the slide member so as to be movable in the direction of the rotation axis.

  As described above, in the friction welding apparatus according to the first aspect of the present invention, with the screw shaft inserted into the hollow portion of the rotating shaft, the rotating shaft is moved in the direction of the rotation axis so that the rotating tool is attached to the bonded portion. Press. For this reason, the overall length in the direction of the rotation axis can be shortened, and the applied pressure can be transmitted straight to the rotary tool, preventing rotation of the rotation shaft during friction welding and stabilizing the welding quality, and the durability of the friction welding device. Can be improved.

  In the second invention, the rotation shaft is inserted into the first bearing member of the slide member and held by the first bearing member, so that the rotation support of the rotation shaft is stabilized and the entire apparatus can be downsized.

  In the third aspect of the invention, the configuration of the entire apparatus is simplified by providing the rotating cylinder splined to the outer peripheral portion of the rotating shaft with the function of transmitting the rotational force to the rotating shaft and the function of preventing rotation of the rotating shaft. Can do.

  In the fourth invention, since the guide rail of the apparatus main body guides the slide member in the direction of the rotational axis, the movement of the rotational axis in the axial direction can be stabilized with a simple structure.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In addition, the following embodiment is an essentially preferable illustration, Comprising: It does not intend restrict | limiting the range of this invention, its application thing, or a use.

-Configuration of friction welding device-
FIG. 1 shows a joining gun 1 provided with a friction welding apparatus according to an embodiment of the present invention. The joining gun 1 includes a grip frame 2 and a joining unit 3 as a friction joining device. For example, the grip frame 2 is attached to the wrist of a robot (not shown), and a plurality of plate materials W1 and W2 of a workpiece W made of a light metal such as an aluminum alloy, a magnesium alloy, or a zinc alloy used in an automobile body are stacked in the thickness direction. In such a state, the joining unit 3 joins in a dot shape.

  As shown in FIGS. 2 and 3, the joining unit 3 includes an apparatus main body 4, a pressing shaft motor 5 as first rotation driving means, and a rotating shaft motor 6 as second rotation driving means. . A harness (not shown) connected to a control panel for controlling the friction welding device is connected to the connector portion 5a of the pressing shaft motor 5 and the connector portion 6a of the rotary shaft motor 6.

  As shown in FIG. 3, a screw shaft support 8 having a bearing 8a is provided at the upper end of the housing body 7 of the apparatus body 4. In the screw shaft support portion 8, a screw shaft 10 extending in the direction of the rotation axis (indicated by X in FIGS. 2 and 3) is supported so as to be rotatable and immovable in the direction of the rotation axis. The screw shaft 10 includes a shaft portion 10a on the proximal end side and a screw portion 10b on the distal end side, and is supported by the bearing 8a of the screw shaft support portion 8 on the shaft portion 10a.

  As shown in FIG. 2, first rotation transmission means 11 for transmitting the rotational force of the pressing shaft motor 5 to the screw shaft 10 is provided on the upper side of the apparatus main body 4. The first rotation transmission means 11 includes a pressing pulley 11a fixed to the proximal end of the screw shaft 10, a first driving pulley 11b fixed to the first driving shaft 5b of the pressing shaft motor 5, and the first pulley 11b. A pressing side belt 11c wound around the driving pulley 11b and the pressing side pulley 11a, and a first housing 11d surrounding these are provided. When the pressing shaft motor 5 is driven by the action of the first rotation transmitting means 11, the pressing side belt 11c is driven by the first driving pulley 11b, and the pressing side pulley 11a rotates. Is designed to rotate.

  Further, as shown in FIG. 3, a cylindrical slide member 12 is screwed into the screw portion 10 b of the screw shaft 10. A nut portion 12a having a thread groove is inserted and fixed to the inner peripheral surface of the base end side of the slide member 12, while a first bearing member 12b is attached to the inner peripheral surface of the distal end side. ing.

  A guide rail 7a having a rectangular cross section extending along the direction of the rotation axis is provided on the inner surface of the housing body 7 of the apparatus body 4. An engagement portion 12c having a U-shaped cross section that engages with the guide rail 7a is provided on the outer peripheral surface of the slide member 12. When the engaging portion 12c engages with the guide rail 7a, the slide member 12 is supported so as not to rotate with respect to the apparatus main body 4 and to be movable in the direction of the rotation axis. Note that the guide rail 7a side may be formed in a groove shape with a U-shaped cross section, and the protrusion of the engaging portion 12c of the slide member 12 may be engaged in the groove.

  A proximal end side of the rotary shaft 20 to which the rotary tool 30 (shown in FIG. 1) is attached is inserted on the distal end side of the slide member 12. A rotary tool mounting portion 20a for mounting the rotary tool 30 is provided at the distal end of the rotary shaft 20, and a hollow portion 20b having an opening is provided at the proximal end. The screw shaft 10 and the rotating shaft 20 are provided concentrically, and the base end side of the rotating shaft 20 is connected to the first bearing member 12b in a state where the screw shaft 10 is inserted into the hollow portion 20b of the rotating shaft 20 from the distal end side. The slide member 12 is inserted and is rotatably supported. Thus, the rotation shaft 20 is moved in the direction of the rotation axis along with the movement of the slide member 12 while rotating.

  A second rotation transmission means 21 for transmitting the rotational force of the rotary shaft motor 6 to the rotary shaft 20 is provided at the lower end of the housing main body 7 of the apparatus main body 4. The second rotation transmission means 21 includes a cylindrical rotary cylinder 22 splined to the outer peripheral portion of the rotary shaft 20, a rotation-side pulley 21 a into which the rotary cylinder 22 is inserted and fixed, and a first rotary shaft motor 6. A second driving pulley 21b fixed to the two driving shafts 6b, a rotation side belt 21c wound around the second driving pulley 21b and the rotation side pulley 21a, and a second housing 21d surrounding these. ing. When the rotation shaft motor 6 is driven by the action of the second rotation transmission means 21, the rotation-side belt 21c is driven by the second driving pulley 21b, the rotation-side pulley 21a rotates, and the rotation cylinder 22 receives the rotation shaft motor. 6 rotational force is transmitted. As a result, the rotary shaft 20 splined to the rotary cylinder 22 rotates. Moreover, since the rotating shaft 20 and the rotating cylinder 22 are spline-coupled, the rotating shaft 20 can move in the direction of the rotation axis.

  The rotating shaft 20 is rotatably supported by the apparatus main body 4 by a rotation support member 23. The rotation support member 23 includes a second bearing member 23 a that rotatably supports the rotary cylinder 22 with respect to the apparatus main body 4. The rotating cylinder 22 is supported by the apparatus main body 4 so as not to move in the direction of the rotation axis.

  With the above configuration, the rotating shaft 20 is configured to be rotated by the rotating shaft motor 6 and moved up and down in the direction of the rotating shaft by the pressing shaft motor 5.

  As shown in FIG. 1, the rotary tool 30 attached to the rotary tool attachment portion 20 a on the tip surface of the rotary shaft 20 and the receiving member attached to the tip of the L-shaped arm 2 a in the side view of the grip frame 2. 31, the joined portion of the workpiece W made of the first and second plate members W <b> 1 and W <b> 2 is sandwiched.

-Action of friction welding device-
First, when the rotating shaft motor 6 of the joining gun 1 is driven, the rotating side belt 21c is driven by the second driving pulley 21b, the rotating side pulley 21a rotates, and the rotating force of the rotating shaft motor 6 is applied to the rotating cylinder 22. Communicated. As a result, the rotary shaft 20 splined to the rotary cylinder 22 rotates. Then, the rotary tool 30 is rotated around the rotation axis.

  After the rotational speed of the rotary tool 30 reaches the target rotational speed, when the pressing shaft motor 5 is driven while rotating the rotary tool 30, the pressing side belt 11c is driven by the first driving pulley 11b, The side pulley 11a rotates, and thereby the screw shaft 10 rotates.

  When the screw shaft 10 is rotated, the slide member 12 screwed into the screw shaft 10 is lowered. As a result, the rotating shaft 20 supported by the slide member 12 is lowered.

  In this way, the rotary tool 30 is lowered until the pressing shaft motor 5 is driven to contact the surface of the workpiece W. As a result, the work W is sandwiched between the rotary tool 30 and the receiving member 31, and the work W is pressed in the direction of the rotation axis (downward in FIG. 2). Thus, frictional heat is generated by friction between the rotary tool 30 and the surface of the first plate material W1. This frictional heat is transmitted from the first plate material W1 to the second plate material W2, and the second plate material W2 is also softened.

  Then, the rotation and pressing of the rotary tool 30 are continued. Thereby, plastic flow is generated in the first and second plate members W1, W2.

  In this way, after the plastic flow in the workpiece W is continued for a predetermined time, the rotary tool 30 is raised by rotating the pressing shaft motor 5 in the reverse direction while the rotary tool 30 is rotated. Pull out from inside.

  Thereafter, the workpiece W is rapidly cooled and hardened, and the joining of the workpieces W is completed.

-Effect of the embodiment-
Therefore, in the friction welding apparatus according to the above embodiment, with the screw shaft 10 inserted into the hollow portion 20b of the rotation shaft 20, the rotation shaft 20 is moved in the direction of the rotation axis and the rotating tool is pressed against the bonded portion. I am letting. For this reason, the overall length in the direction of the rotational axis can be shortened, and the applied pressure can be transmitted straight to the rotary tool 30, so that the rotational quality of the rotational shaft 20 during friction welding can be prevented and the joining quality can be stabilized. The durability of can be improved.

  Further, by inserting the rotating shaft 20 into the first bearing member 12b of the slide member 12 and holding the rotating shaft 20 on the first bearing member 12b, the rotation support of the rotating shaft 20 is stabilized and the entire apparatus can be downsized.

  Furthermore, the configuration of the entire apparatus can be simplified by providing the rotating cylinder 22 splined to the outer periphery of the rotating shaft 20 with the function of transmitting the rotational force to the rotating shaft 20 and the function of preventing rotation of the rotating shaft 20. Can do.

  Further, since the guide rail 7a of the apparatus body 4 guides the slide member 12 in the direction of the rotation axis, the movement of the rotation shaft 20 in the direction of the axis can be stabilized with a simple structure.

  As described above, the present invention is useful as a drive device for a friction point joining rotary tool for joining a plurality of plate materials made of a light metal such as an aluminum alloy and joining the plate materials by plastic flow.

It is a side view of the joining gun provided with the joining unit concerning this embodiment. It is a side view which shows a joining unit. It is the III-III sectional view taken on the line of FIG.

Explanation of symbols

3 Joining unit (friction welding equipment)
4 Device body 5 Press shaft motor (first rotation drive means)
6 Rotating shaft motor (first rotation driving means)
7a guide rail 10 screw shaft 11 first rotation transmission means 12 slide member 12b first bearing member 20 rotation shaft 20b hollow portion 21 second rotation transmission means 22 rotary cylinder 23 rotation support member 23a second bearing member 30 rotary tool

Claims (4)

A friction welding device that presses against a bonded portion while rotating a tip portion of a rotary tool to generate frictional heat, softens the bonded portion, and bonds the bonded portion,
The rotary tool is attached to the distal end, and a rotation shaft provided with a hollow portion having an opening at the proximal end;
A screw shaft that is concentric with the rotation shaft and can be inserted into a hollow portion of the rotation shaft, and is supported so as to be rotatable with respect to the apparatus body and immovable in the direction of the rotation axis;
First rotational driving means for rotationally driving the screw shaft via first rotational transmission means;
The base end side of the rotating shaft is rotatably held, and is screwed to the screw shaft so as to be supported by the apparatus main body so as to be movable in the direction of the rotational axis. A slide member to be
Second rotational drive means for rotationally driving the rotational shaft via second rotational transmission means;
A friction bonding apparatus comprising: a rotation support member that rotatably supports the rotation shaft. The friction welding apparatus according to claim 1, wherein
The slide member has a cylindrical shape, and a thread groove is formed on the inner peripheral surface of the base end side, and a first bearing member is provided on the inner peripheral surface of the distal end side,
A friction welding apparatus, wherein a proximal end of the rotating shaft is inserted into a distal end side of a slide member and is rotatably held by the first bearing member. In the friction welding apparatus according to claim 1 or 2,
The second rotation transmission means includes a rotating cylinder that is spline-coupled to the outer peripheral portion of the rotating shaft, and the rotational force of the second rotation driving means is transmitted to the rotating cylinder,
The said rotation support member is equipped with the 2nd bearing member which supports the said rotation cylinder rotatably with respect to an apparatus main body, The friction welding apparatus characterized by the above-mentioned. In any one friction welding apparatus of Claims 1-3,
A friction welding apparatus according to claim 1, wherein a guide rail for guiding the slide member in the axial direction of the rotation shaft is provided in the apparatus main body.

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