JP4362418B2 - Friction stir welding equipment - Google Patents

Description

  The present invention relates to a friction stir welding apparatus for joining laminated portions formed by laminating a plurality of members.

  As a method of laminating members and joining the laminated portions, spot welding is common, but in recent years, joining by friction stir welding has been proposed. As such a friction stir welding apparatus that performs friction stir welding of a part, for example, the one described in Patent Document 1 can be cited.

  This type of friction stir welding apparatus 1 schematically shown in FIG. 5 includes a rotation operation motor (not shown) for rotating the friction stir welding tool 2 and the friction stir welding tool 2 in the vertical direction in FIG. And a displacement motor (not shown) for linearly displacing. The rotation motor is accommodated in the casing 3, and the displacement motor is accommodated in the sub casing 4. That is, in the friction stir welding apparatus 1, the friction stir welding tool 2 and the rotation operation motor are arranged on the same axis.

  When performing friction stir welding with the friction stir welding apparatus 1, the laminated portion 6 is placed on the receiving portion 5 disposed below, and the friction stir welding tool 2 that rotates is laminated under the action of the displacement motor. The probe 6 of the friction stir welding tool is finally buried in the laminated portion 6 while moving downward toward the portion 6. Along with this burying, the meat of the laminated portion 6 is agitated. In other words, the meat is plastically flowed.

Japanese Patent No. 3429475

  As described above, in the technique described in Patent Document 1, the friction stir welding is performed by rotating the friction stir welding tool 2 with the rotation motor and then burying it in the laminated portion 6 with the displacement motor. I am doing so. In this case, since the two motors of the rotation operation motor and the displacement motor are necessary, the entire apparatus is increased in size. For this reason, when trying to friction stir weld a workpiece having a complicated shape such as a member having a curved portion or a bent portion, the probability that the apparatus interferes with the workpiece increases. When such a situation occurs, it becomes difficult to dispose the work directly under the friction stir welding tool, and eventually the friction stir welding itself becomes difficult.

  In addition, when the apparatus configured as described above is used while being held by an articulated robot, for example, the weight of the apparatus is large, so that a load applied to the holding means of the articulated robot becomes large.

  The present invention has been made to solve the above-described problems, and can provide a friction stir welding apparatus that can avoid an increase in the size of the apparatus and that has a low load on the gripping means of an articulated robot. With the goal.

In order to achieve the above object, the present invention is a friction stir welding apparatus for friction stir welding a laminated portion formed by laminating a plurality of members,
An arm member for supporting the laminated portion;
A friction stir welding tool for friction stir welding the laminated portion;
Displacement rotating means comprising a single motor and serving as both a displacement means for displacing the friction stir welding tool in a direction away from or approaching the laminated portion and a rotating means for rotating the friction stir welding tool When,
A casing surrounding the displacement rotating means and connected to one end of the arm member;
A rod connecting the displacement rotating means and the friction stir welding tool;
A mounting member disposed on the other end of the arm member and mounting the stacked portion;
It is characterized by having.

  In the present invention, the displacement means for displacing the friction stir welding tool also serves as a rotation means for rotating the friction stir welding tool, and is configured as a displacement rotation means. For this reason, an apparatus structure can be simplified and the size reduction of a friction stir welding apparatus can be achieved after all.

  Moreover, since the weight of the friction stir welding apparatus is reduced, the load applied to the gripping means is reduced even when the articulated robot is gripped and used.

  According to the present invention, the displacement means for displacing the friction stir welding tool also serves as the rotating means for rotating the friction stir welding tool. For this reason, the configuration of the friction stir welding apparatus is simplified, and as a result, the friction stir welding apparatus can be reduced in size and weight. Therefore, it is possible to avoid interference between the apparatus and the workpiece, and it is possible to reduce the load applied to the gripping means or the like of the articulated robot.

  Preferred embodiments of the friction stir welding apparatus according to the present invention will be described below in detail with reference to the accompanying drawings.

  A schematic overall longitudinal sectional view of the friction stir welding apparatus according to the present embodiment is shown in FIG. This friction stir welding apparatus 10 is positioned and fixed by being connected to the tip of an arm 11 of an articulated robot (not shown), bent arm member 12, friction stir welding tool 14, and this friction stir welding tool As shown in FIG. 1, a displacement rotation motor 16 serving as a displacement rotation means for rotating and moving in the vertical direction in FIG. 1, a casing 18 housing the displacement rotation motor 16, the displacement rotation motor 16, and the friction stir welding tool 14 And a mounting member 22 disposed at the other end of the arm member 12.

  The arm member 12 has a long portion 26 that gradually increases in width toward the right in FIG. 1, a rising portion 28 that rises substantially vertically from the long portion 26, and a left portion in FIG. 1 from the rising portion 28. The casing 18 is connected to a connection support frame 32 fixed to the front end of the support portion 30.

  As shown in FIG. 2, a mounting member 22 for mounting a stacked portion 34 formed by stacking a first work W1 and a second work W2 is placed on the left end of the long portion 26 in FIG. Is fixed. A hollow cylindrical body-shaped concave portion 38 is provided in the substantially central portion of the upper end surface of the mounting member 22.

  As shown in FIG. 2, the friction stir welding tool 14 connected to the support portion 30 of the arm member 12 through the connection support frame 32 is provided with a rotating body 40 and a screw portion provided at the tip of the rotating body 40. The rotating body 40 is connected to the rod 20. As the probe 44, a probe whose diameter is smaller than the opening diameter of the recess 38 is selected.

  Around the friction stir welding tool 14, a pressing member 48 that presses the laminated portion 34 at its lower end surface is disposed. In other words, the friction stir welding tool 14 is surrounded by the pressing member 48. Of course, a through hole 50 is provided in the lower end surface of the pressing member 48, and the probe 44 of the friction stir welding tool 14 protrudes from the through hole 50.

  The diameter of the tip portion of the pressing member 48 is set so that the curved portion R and the bent portion provided on the upper second workpiece W2 are flattened by pressing the stacked portion 34 over a wider range than necessary. It is set smaller than the abdomen. That is, the pressing member 48 is provided with a small diameter portion 52 and a large diameter portion 54.

  An annular stepped portion 56 is provided at the upper end portion of the large-diameter portion 54 by bending the upper end portion toward the outer diameter direction. The annular step portion 56 is blocked by an annular blocking portion 62 provided at the lower end portion of the spring cover 60 that accommodates the coil spring 58, thereby preventing the pressing member 48 from coming off from the spring cover 60. Yes.

  The upper part of the rotating body 40 is accommodated in the rotating body cover 64. At the upper end portion of the rotating body cover 64, an annular coupling allowance 66 formed by bending from the longitudinal direction (vertical direction) of the rotating body cover 64 toward the horizontal direction is provided. These are connected and fixed to the side peripheral wall of the spring cover 60 by bolts (not shown).

  A bearing 68 is interposed between the rotator cover 64 and the upper part of the rotator 40, and the presence of the bearing 68 prevents the rotator cover 64 and the spring cover 60 from rotating. . In FIG. 2, reference numeral 70 indicates a bush.

  The lower end portion of the coil spring 58 is seated on the upper end surface of the annular step portion 56 of the pressing member 48, while the upper end portion is seated on the lower end surface of the annular coupling allowance 66 of the rotating body cover 64. Accordingly, the pressing member 48 is elastically biased toward the arm member 12 by the coil spring 58. As described above, the annular step portion 56 of the pressing member 48 is blocked by the annular blocking portion 62 of the spring cover 60, thereby preventing the pressing member 48 from coming off from the spring cover 60.

  The rotating body 40 is connected to the rod 20. As will be described later, the friction stir welding tool 14 rotates as the rod 20 rotates under the action of the displacement rotation motor 16.

  The rod 20, which is a hollow cylinder, is first connected to the displacement rotation motor 16. Therefore, the displacement rotation motor 16 rotates as the rotation is urged.

  Further, the rod 20 moves down and up as the screw nut 72 rotates inside the casing 18. That is, a screw portion 74 of a screw nut 72 is passed through the screw 73, and a connection allowance 76 of the screw nut 72 is connected to the upper end portion of the rod 20. For this reason, the screw nut 72 rotates and moves down and up while being guided by the screw 73, so that the rod 20 connected to the connecting margin 76 of the screw nut 72 moves down and up.

  A bearing 80, a rotary bush 82 and a bearing 84 are interposed between the rod 20 and the casing 14.

  The upper end of the screw 73 is connected and fixed to the casing 14. For this reason, the screw 73 does not rotate.

  The friction stir welding apparatus 10 according to the present embodiment is basically configured as described above. Next, the function and effect will be described.

  The articulated robot moves the friction stir welding apparatus 10 to the laminated portion 34 where the first workpiece W1 and the second workpiece W2 are laminated, and the laminated portion 34 is moved between the mounting member 22 and the friction stir welding tool 14. It arrange | positions between the probes 44. In this case, as the first workpiece W1 and the second workpiece W2, those made of so-called 5000 series aluminum whose JIS symbol number is in the 5000 range are selected.

  Next, the displacement rotation motor 16 is urged to rotate, whereby the screw nut 72 rotates. Along with this rotation operation, the screw nut 72 moves downward while being guided by the screw 73, and as a result, the rod 20 connected to the screw nut 72 moves downward. Following this, the friction stir welding tool 14 descends, and eventually the friction stir welding tool 14 is placed on the long portion 26 of the arm member 12 and thus on the mounting member 22. Approach toward 34. Finally, as shown in FIGS. 2 and 3, the stacked portion 34 is sandwiched between the mounting member 22 and the pressing member 48, and covers the concave portion 38 of the mounting member 22 at this time.

  When the lowering operation of the rod 20 is further continued, the pressing member 48 is pressed by the stacked portion 34. As a result, the coil spring 58 (see FIG. 2) is contracted and the pressing member 48 moves upward. As a result, the probe 44 of the friction stir welding tool 14 reaches the through hole 50 of the pressing member 48.

  In this state, when the rotation urging of the displacement rotary motor 16 is further continued, the probe 44 of the friction stir welding tool 14 protrudes from the through hole 50 of the pressing member 48 and is buried in the stacked portion 34.

  When the probe 44 of the friction stir welding tool 14 that rotates is brought into sliding contact with the upper end surface of the laminated portion 34, frictional heat is generated in the laminated portion 34. For this reason, the contact part of the probe 44 in the laminated part 34 and its vicinity soften, and the probe 44 is further buried in the laminated part 34 as shown in FIGS. As a result, the meat of the laminated portion 34 flows into the recess 38. As described above, since the diameter of the horizontal section of the recess 38 is larger than the diameter of the probe 44, this inflow easily proceeds.

  Thus, in the present embodiment, the probe 44 of the friction stir welding tool 14 is buried in the laminated portion 34 by energizing the displacement rotary motor 16 in rotation. Thereby, a series of steps of moving the friction stir welding tool 14 and joining the laminated portion 34 can be performed by one displacement rotary motor 16.

  For this reason, the structure of the friction stir welding apparatus 10 can be simplified compared with the apparatus which concerns on a prior art. Thereby, the friction stir welding apparatus 10 can be reduced in size. Moreover, since the friction stir welding apparatus 10 is reduced in weight, the load applied to the articulated robot can be reduced.

  The softened meat of the laminated portion 34 is agitated (plastic flow) by the probe 44. At this time, as described above, in the laminated portion 34, the portion of the meat embedded in the probe 44 plastically flows into the concave portion 38, so that the meat does not rise from the portion where the probe 44 is buried. Therefore, no burr is formed. Thus, by providing the recess 38 in the mounting member 22, the laminated portion 34 can be friction stir welded without forming burrs. For this reason, since the thickness of the laminated portion 34 is not reduced, the bonding strength of the laminated portion 34 is increased.

  In addition, in this case, as shown in FIG. 4, since the laminated portion 34 is pressed over a wide range by the lower end surface of the pressing member 48, the gap between the first workpiece W1 and the second workpiece W2 is crushed. That is, since no gap is formed between the first workpiece W1 and the second workpiece W2, the corner portion of the rotating body 40 of the friction stir welding tool 14 that rotates is unlikely to be in sliding contact with the upper second workpiece W2. Thereby, it can avoid that a hole is formed in the 2nd workpiece | work W2.

  In this way, the friction stir welding is performed, and at the same time, as the probe 44 is buried, the protruding portion 102 is formed on the surface of the second workpiece W2 facing the first workpiece W1, and the second workpiece W1 is second. A depression 100 is formed on the surface facing the workpiece W2, and the protrusion 102 is fitted into the depression 100. In addition, the lower end part of the depression part 100 is a non-stirring part (plastic deformation part) where plastic flow of meat is not performed. That is, the protruding portion 102 is fitted into the depressed portion 100 formed into a shape corresponding to the concave portion 38 by plastic deformation, thereby providing a so-called caulking state. Thus, the joining strength of the laminated portion 34 is also improved by forming the caulking state between the first work W1 and the second work W2.

  After the agitation is started and the probe 44 is buried, the displacement rotation motor 16 is de-energized to stop the rotation of the probe 44, thereby stopping the plastic flow of the meat. Next, the displacement rotation motor 16 is urged to rotate in the direction opposite to the above, and the screw nut 72 is rotated in the reverse direction. As a result, the probe 44 of the friction stir welding tool 14 is detached from the laminated portion 34 following the upward movement of the screw nut 72 and, consequently, the rod 20. Further, the pressing member 48 separated from the laminated portion 34 is elastically biased toward the arm member 12 by the coil spring 58 and returns to the original position.

  During this time, the meat of the laminated portion 34 is cooled and solidified, and the first workpiece W1 and the second workpiece W2 are integrally solid-phase bonded. On the side of the first workpiece W1 in the laminated portion 34 thus joined, there is a cylindrical convex portion that is formed to protrude as the meat flowing into the concave portion 38 is cooled and solidified. That is, in this case, the outer diameter of the convex portion is substantially the same as the diameter of the concave portion 38.

  In the above-described embodiment, the case where two workpieces are friction stir welded is described as an example. However, the number of workpieces to be stacked is not limited to two, but three or more workpieces. You may make it laminate | stack.

  Further, it is not particularly necessary to fill the entire space of the concave portion 38 with the meat of the laminated portion 34.

1 is a schematic overall longitudinal sectional view of a friction stir welding apparatus according to the present embodiment. It is a principal part expansion schematic longitudinal cross-sectional view of the friction stir welding apparatus of FIG. It is a schematic whole longitudinal cross-sectional view which shows the state by which the friction stir welding apparatus of FIG. 1 was closed and the laminated part was clamped. It is a principal part expansion schematic longitudinal cross-sectional view which shows the state by which the tool for friction stir welding rotates and a laminated part is friction stir welded. It is a schematic whole side view of the friction stir welding apparatus which concerns on a prior art. It is a principal part expansion schematic plan view of an apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Friction stir welding apparatus 12 ... Arm member 14 ... Friction stir welding tool 16 ... Displacement rotation motor 18 ... Casing 20 ... Rod 22 ... Mounting member 34 ... Laminate part 38 ... Recessed part 44 ... Probe 48 ... Pressing member 58 ... Coil Spring 72 ... Screw nut 73 ... Screw W1, W2 ... Workpiece

Claims (1)

A friction stir welding apparatus for friction stir welding a laminated portion formed by laminating a plurality of members,
An arm member for supporting the laminated portion;
A friction stir welding tool for friction stir welding the laminated portion;
Displacement rotating means comprising a single motor and serving as both a displacement means for displacing the friction stir welding tool in a direction away from or approaching the laminated portion and a rotating means for rotating the friction stir welding tool When,
A casing accommodating the displacement rotating means and connected to one end of the arm member;
A rod connecting the displacement rotating means and the friction stir welding tool;
A mounting member disposed on the other end of the arm member and mounting the stacked portion;
A friction stir welding apparatus comprising:

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