JPH091326A - Work welding method and welding device - Google Patents

Abstract

(57) [Summary] [Purpose] To provide a welding method for a work and an apparatus therefor, in which a good welding result can be obtained such that there is no mark and the thickness is even. [Structure] By holding a work W composed of a plurality of divided bodies a and b having a curved joining line L and rotating the workpiece W by a predetermined angle, the joining line L is opposed to a stationary welding torch 13 and the welding line is formed. Weld along L. In this case, the portion of the joining line L of the workpiece W facing the welding torch 13 is welded in a state of being brought close to the rotation center O of the workpiece W.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention can be used when a plurality of divided bodies are used and the joining line is curved, for example, when a fuel tank for a motorcycle is used as a work and the work is joined by welding. The present invention relates to a work welding method and a welding device.

[0002]

2. Description of the Related Art For example, in a fuel tank for a motorcycle, a main body is formed by an upper tank wall having a substantially U-shaped cross section and a lower tank wall closing a lower opening of the upper tank wall. When the shape of the upper tank is complicated, the upper tank wall is formed by welding the left and right divided bodies. One of the welding devices is disclosed in, for example, Japanese Utility Model Publication No. 58-32857. This device is for abutting left and right divided works which are the upper tank wall of a fuel tank, and welding them with a welding torch along a joining line by the abutting.

[0003]

By the way, in this welding apparatus, the work is fixed by upper and lower jigs, and the welding torch is moved to perform welding. The joining line of the work is
Since it is a fuel tank, it goes up and down from the lowest part to the front and back, and when it is welded as it is, welding dripping may occur at the part where the slope is steep and welding marks may remain. In order to prevent this, it is necessary to devise the attitude of the welding torch, which deteriorates the workability of welding.

The present invention has been made in view of the above problems, and its main object is to provide a welding method and a welding apparatus for a work which are excellent in workability.

[0005]

In order to achieve the above-mentioned object, the invention of claim 1 is composed of a plurality of divided bodies, and welds a work piece whose joining line is curved to form the divided bodies. A method of joining, in which the workpieces are held and rotated by a predetermined angle to perform welding along the joining line while moving the joining line relative to the welding torch with the joining line facing the welding torch. .

According to a second aspect of the present invention, there is provided the welding method according to the first aspect, wherein the portion of the joining line of the workpieces facing the welding torch is welded in a state of being brought close to the rotation center of the workpieces.

Further, the welding method of claim 3 is the same as that of claim 1.
Alternatively, in 2, the welding torch is moved along a part of the joining line.

According to a fourth aspect of the present invention, there is provided a device for welding workpieces, each of which is composed of a plurality of divided bodies and has a joining line having a curved shape, for joining the divided bodies. And rotating means for rotating the holding means by a predetermined angle so as to move the joining line relative to the welding torch in a state of facing the welding torch.

Further, the welding device according to claim 5 is the welding device according to claim 4.
In the above, the holding means holds a portion of the joining line of the workpieces facing the welding torch in a state of being close to the rotation center of the workpieces.

A welding device according to a sixth aspect of the present invention is the welding device according to the fourth or fifth aspect, further including torch driving means for moving the welding torch along the joining line.

[0011]

According to the invention of claim 1 or 4, the welding is performed with the welding line facing the welding torch by holding a workpiece made of a plurality of divided bodies having a curved welding line and rotating the workpiece by a predetermined angle. Therefore, the welding point always corresponds to an appropriate point, for example, the lowermost portion of the joining line, so that no welding sag occurs and a good welding result is obtained.
Here, since the welding torch can be kept stationary and it is not necessary to move the welding torch by devising its posture, workability is good.

In the second or fifth aspect of the invention, since the portion of the joining line of the workpieces facing the welding torch is welded in the state of being brought close to the center of rotation of the workpieces, rattling due to backlash of the means for rotating the workpieces is provided. As a result, unexpected fluctuations in welding speed can be prevented, and welding quality can be maintained high.

According to the third or sixth aspect of the invention, since the welding torch is moved along a part of the joining line, it is not necessary to rotate the work within the angular range of the movement, and the power for the rotation is supplied. Can be reduced.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below in detail with reference to the drawings. 1 to 6 show an embodiment of the present invention, FIGS. 1 to 4 show a work holding state, and FIG. 1 is a plan view of the apparatus, which is a sectional view taken along the line I--I of FIG. 2, and FIG. 1 is a plan view of the apparatus taken along line II-II in FIG. 1, FIG. 3 is a sectional view taken along line III-III in FIG. 1, FIG. 4 is a sectional view taken along line IV-IV in FIG. 3, and FIGS. FIG. 5 is a vertical cross-sectional view of the device seen from the side, and FIG.
FIG. 6 is a view on arrow VI of FIG.

As shown in the plan view of FIG. 2, the welding apparatus comprises a fixed frame 1 framed in a substantially rectangular shape, which is fixedly installed on the base 2 of FIG. The first controller 3 is mounted on the left side of the fixed base 1 shown in FIG. 2, and the mounting base 4 is mounted on the rear side thereof. A servomotor 5 and a gear reducer 6 connected to the servomotor 5 are installed on the mounting table 4, and the rotating power of the reducer 6 reversibly rotates a rotating shaft 8 via a coupling 7. This rotation control is performed by the second controller 30 described later. The rotating shaft 8 is rotatably supported by a bearing 10 installed in a stay 9 on the fixed base 1, and the stay 9 is also provided on the right side opposite to this.
Another rotating shaft 8A is rotatably provided via a bearing 10A on A. The servo motor 5, the gear reducer 6, the coupling 7, and the rotating shafts 8 and 8A constitute a rotating means for the work.

A base 11 is fixed on the mounting base 4, and a robot 12 capable of controlling 6 axes via the base 11.
However, it is erected as shown in FIG. 1, and a welding torch 13 shown by a broken line in FIG. 1 and shown by a solid line in FIG. 4 is attached to the tip of an arm 12a of the robot 12. The robot 1 is provided at a position adjacent to the first controller 3 shown in FIG.
The 2nd controller 30 which controls 2 is installed.

As shown in FIG. 2, brackets 15 and 15A are fixed to opposite ends of the rotary shafts 8 and 8A, and a substantially square rotary substrate 16 is attached to the brackets 15 and 15A. . Three openings 51, 52, 53 extending in the front-rear direction are formed in the rotary board 16, and the welding torch 13 (FIG. 1) is inserted through the elongated opening 52 in the center thereof. Guide bars 18 are attached to the four corners of the rotary substrate 16, and as shown in FIG. 1, the guide bars 18 extend downward, and lifter attachment plates 19 are attached to the lower ends thereof. The lifter mounting plate 19 is in a positional relationship where it does not interfere with the fixed base 1 when it is rotated about the rotation shaft 8.

An elevating table 20 is movably mounted in the middle of the guide bar 18, and the table 20 is driven up and down by a hydraulically driven lifter 21 incorporated between a lifter mounting plate 19. In this lifter 21, the first and second links 21b and 21c, which are connected to each other in an X shape by a connecting pin 21a at the central portion, are pin-connected to the lifter mounting plate 19 and the lifting table 20, respectively, and the hydraulic cylinder 21d is mounted to the lifter. It is connected between the plate 19 and the first link 21b.

On the lifting table 20, FIG. 3 and FIG.
As shown in FIG. 3, the air motor 2 is guided by the lower roller 22, the side roller 23, and the side guide plate 27.
4 and a rack and pinion 25 are mounted on a slide table 26 which is driven to move back and forth in the front-back direction of FIG. The slide table 26 moves forward to the position shown by the phantom line in FIG. 3, and stops when the back end of the bottom groove 29 of the table 26 comes into contact with the forward limit switch 28 attached to the front end of the lifting table 20. Further, as shown by the solid line in FIG. 3, the table 26 retreats to the center of the lifting table 20 and hits the retreat limit switch 31 to stop. All of these controls are performed by the first controller 3.

As shown in FIG. 4, a lower die mount 36 is set on the slide table 26 via a receiving roller 35 mounted on the slide table 26 so as to overlap with the upper die. The mounting base 36 is pressed onto the elevating table 20 together with the slide table 26 by the operation of the lower lock device 37. Simultaneously with this lock, the lower roller 22 and the receiving roller 35 receive a large vertical load and sink, and the slide table 26 and the lower die mount 3
6 is locked on the lifting table 20.

As shown in FIG. 4, on the lower die mount 36, a lower holding die which comes into contact with the lower surface of a work W having a U-shaped cross section, which is a fuel tank composed of divided bodies a and b, at several points. 40 are erected.

On the other hand, an upper die mounting base 42 facing the lower die mounting base 36 is attached to the bottom surface of the upper rotary substrate 16. The upper die mounting base 42 is also fixed by the upper locking device 43, and the upper holding die 44 is attached to the lower side thereof.
The upper holding die 44 is configured as a pair of parallel die bodies that contact both side edges of the curved joining line L on the inner surface (upper surface) of the work W. Further, the welding torch 13 is inserted inside the upper holding die 44, and the welding torch 13 is inserted.
An insertion space 47 is formed to allow relative rotation of the upper holding die 44 and the upper holding die 44, and an insertion space 48 communicating therewith is also formed in the upper die mount 42.
Are communicated with the opening 52 of the rotating substrate 16.

Next, the procedure for setting the work W in this welding apparatus will be described. As shown by phantom lines in FIG. 5, the lower die mount 36 including the lower holding die 40 is attached to the slide table 26
Along with it, it is advanced to the left (front side). This movement is performed by the air motor 24 and the rack and pinion 25 shown in FIG.
Made in. The advance limit is defined by the switch 28 in FIG. In this state, as shown by the arrow A in FIG. 5, the work W is manually set on the lower holding die 40, the slide table 26 is retracted, and the work W is carried into the apparatus together with the lower holding die 40. To be done.

When the work W reaches the specified position, the lower lock device 37 locks the slide table 26 and the lower die mount 36. Then, the hydraulic cylinder 21d of the lifter 21 is extended, so that the lifting table 20 is lifted and the work W is also lifted. As shown in FIG. 1, the lower end curved surface of the upper holding die 44 contacts the inner surface of the work W and the lower holding die is held. The work W is held between 40 and 40. As a result, as shown in FIG. 4, the insertion space 1 in the upper holding die 44
The joining line L is located just below 7. The operations of the slide table 26, the lower lock device 37, and the lifter 21 are controlled by the first controller 3.

When the setting of the work W is completed, the robot 12 of FIG. 1 is activated by the control signal from the second controller 30 of FIG. 2, and the welding torch 1 mounted at the tip thereof.
3 is introduced through the insertion space 17 of FIG. 4 and guided so as to match the lowest part P on the joining line L of the workpiece W in a stationary state.

Next, by giving a welding start command to the first controller 3 of FIG.
The servomotor 5 is rotated by a control signal from 0, the rotary shaft 8 is rotated through the gear reducer 6 and the coupling 7, and the rotary substrate 16, the guide bar 18, the lifter mounting plate 19 of FIG. The rotated portion D including the lifting table 20 and the lifter 21 rotates in the X direction, and the work W also rotates in the X direction. On the other hand, the welding torch 13 is energized by the control signal from the second controller 30. The welding torch 13 is tilted and set so that when the rotated portion D rotates in the direction of the arrow X, the tip of the welding torch 13 is rearward with respect to the welding proceeding direction B as shown by the broken line in the figure.

With the rotation of the rotating system in the X direction, the welding progresses on the joining line L while moving the joining line L relative to the welding torch 13, so that the welding torch 13 is always at the lowest position P. Weld on target. Therefore, welding dripping does not occur. As described above, the welding torch 13 may remain stationary, and it is not necessary to move the welding torch 13 by devising its posture, so that the welding workability is good. This welds the inner surface of the right side of the work W. After that, the work W is returned and rotated to the original rest position, the welding torch 13 is tilted in the opposite direction, and the arrow Y of the rotated portion D is moved. With the rotation in the direction, the remaining joining line L is welded and the left inner surface of the work W is welded.

Further, since the work W is not a semicircle but a special curved surface, the position of the welding torch 13 in the second controller 30 and the robot 12 may be slightly changed vertically and horizontally. Controlled. After turning in the Y direction, the work W is turned back to the original rest position. Since the welding torch 13 is inserted into the insertion space 47 formed in the upper holding die 44 and is rotatable relative to the upper holding die 44, the welding torch 13 is also welded by the rotation of the upper holding die 44. The torch 13 does not interfere with the upper holding die 44. Even when the upper holding die 44 is stationary and the welding torch 13 is moved, the welding torch 13 and the upper holding die 44 do not interfere with each other.

Further, while the lowermost part P moves along the joining line L as the work W rotates, the rotary shaft 8 rotates to a level close to the uppermost part P of the lowermost part P. The center (center of rotation of the work W) O is always located. Since the lowest part P and the rotation center O are close to each other in this way, when the rotated part D holding the workpiece W rotates, even if there is backlash in the drive system, rattling due to the backlash occurs. Since the influence can be suppressed, the unexpected fluctuation of the welding speed can be prevented, and the welding quality can be maintained high.

The rotation angle of the rotated portion D in the X and Y directions may be approximately 90 degrees, but in this embodiment, the rotation angle is 45 degrees in the X and Y directions, and the remaining portions are
That is, at both ends L1 and L2 of the welding line L, only the welding torch 13 is moved and controlled to perform welding. As a result, the rotation angle of the rotated portion D can be reduced,
The turning power can be saved significantly.

When the welding is completed, the operation is performed in the direction opposite to the arrow shown in FIG. That is, after the lifting table 20 is lowered and the work W is lowered, the slide table 26 is moved forward (moved to the left), the work W is advanced to the front together with the lower holding die 40, and the work W is moved from the lower holding die 40. Taken out.

The lifting table 20 may be a fixed table so that the rotary substrate 16 can be lifted and lowered. In this case, the fixed table is rotatably supported by the lifting table 20 via the bearing. Further, in this embodiment, the apparatus for manufacturing the upper body of the fuel tank of the motorcycle by welding has been described, but the present invention can be widely applied to other works such as a container having a curved joining line.

[Brief description of the drawings]

FIG. 1 is a plan view of an apparatus according to an embodiment of the present invention, which is I in FIG.
FIG. 2 is a sectional view taken along line I.

FIG. 2 is a plan view of the device taken along line II-II of FIG.

3 is a sectional view taken along line III-III in FIG.

FIG. 4 is a sectional view taken along line IV-IV of FIG. 3;

FIG. 5 is a vertical cross-sectional view of the welding device as viewed from the side.

FIG. 6 is a view on arrow VI of FIG.

[Explanation of symbols]

5, 6, 7, 8, 8A ... Rotating means, 12 ... Torch driving means (robot), 13 ... Welding torch, 17 ... Insertion space,
40, 44 ... Holding means, W ... Work, a, b ... Divided body,
L ... Joining line, O ... Center of rotation of work, P ... Bottom part.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Hayashi Kamiyama 1-1 Kawasaki-cho, Akashi-shi, Hyogo Prefecture Kawasaki Heavy Industries Ltd. Akashi Plant (72) Inventor Tamio Nishikawa 1-1-1 Kawasaki-cho, Akashi-shi, Hyogo Kawasaki Heavy Industries Inside the Akashi Factory (72) Inventor Naohiko Saeki 1-1 Kawasaki-cho, Akashi-shi, Hyogo Kawasaki Heavy Industries Ltd. Inside the Akashi Factory (72) Yuji Shibata 1-1 Kawasaki-cho, Akashi-shi, Hyogo Kawasaki Heavy Industries Ltd. Akashi Factory

Claims (6)

[Claims] 1. A method of welding a work, which comprises a plurality of divided bodies, and whose joining line is curved, by joining the divided bodies together, the work being held and rotated by a predetermined angle, A method for welding a workpiece, wherein welding is performed along the welding line while moving the joining line relative to the welding torch while facing the welding torch. 2. The method of welding a work according to claim 1, wherein a portion of the work joining line facing the welding torch is welded in a state of being brought close to the center of rotation of the work. 3. The method of welding a work according to claim 1, wherein the welding torch is moved along a part of the joining line. 4. A device for welding a work piece, which is composed of a plurality of divided bodies and has a joining line having a curved shape, and joins the divided body members together, and a holding means for holding the work pieces and a predetermined holding means for the holding means. A welding device for a workpiece, comprising: a rotating means for rotating the joint line relative to the welding torch with the joining line facing the welding torch. 5. The welding device for a work according to claim 4, wherein the holding means holds a portion of the joining line of the work facing the welding torch close to the center of rotation of the work. 6. The workpiece welding apparatus according to claim 4, further comprising torch drive means for moving the welding torch along the joining line.