JP2990526B2 - Large and small workpiece welding method - Google Patents

Description

The present invention relates to a welding method for welding a small workpiece to a predetermined position of a large workpiece and an apparatus therefor.
The present invention relates to a method and an apparatus for welding large and small workpieces, which are suitable for preventing shape defects and welding defects due to bending at the time of attaching a large workpiece to a welding jig or deformation during welding.

[Conventional technology]

For example, when a small work such as a roof arch which is a reinforcing member thereof is welded to a large work such as a roof panel of an automobile, a welding method as shown in FIG. 5 has been conventionally employed.

To describe the outline, the roof arch W ₁ is transferred from the pool location weld fixture 1a side by the conveying device 5a, is inserted in the positioning pins 10a of the roof arch placement base 9a of the weld fixture 1a, predetermined position Is positioned and supported. On the other hand, the roof panel W ₂ is transferred to a predetermined position of the welding jig 1a side from the pool location by the transport device 6a.

Roof panel clamping device 11a and the roof panel placement base 12b for positioning gripping the 3 edge of the roof panel W ₂ is provided on the weld fixture 1a. That is, welding jig 1a
With 2箇roof panel clamping device 11a is provided, the roof panel clamping device 11a of each of the three箇the edge WS _1, WS ₂ of both side surfaces are provided on the edge WF to be the reference of the roof panel W ₂ in It is to position gripping than the vertical roof panel W _2. In addition, marginal WF criteria of the roof panel W ₂
Opposite marginal WR the roof panel placement base 12b is provided, it is arranged so as to position the support from below the roof panel W ₂ and.

As described above, the roof panel W ₂ and the roof arch W ₁ is placed on the weld fixture 1a, it is positioned placed abutting engagement with each other.

On the other hand, the welding apparatus 3a, the roof panel W ₂ and the roof arch
It intended to be movably formed on the welding position of the W _1, and a roof panel W ₂ is positioned and supported on the weld fixture 1a and the roof arch W ₁ directly present with welding, combining two workpieces Rufuasshi W _Had formed _three .

[Problems to be solved by the invention]

However, the conventional welding method has the following problems.

Because the three edges of the roof panel, which is a large work, are positioned and gripped from above and below by the roof panel clamp device,
If there is a dimensional error in the manufacture of the roof panel, the roof panel is subjected to a pressing force by the roof panel clamp device, and the entire roof panel is bent. When the roof arch, which is a small work, is permanently welded in this state, the roof panel and the roof arch are pulled toward each other, resulting in a defective work shape. Then, the roof arch and the roof panel are not joined to each other, resulting in poor welding.

Furthermore, since the final welding is performed in a state where the three edges of the roof panel are clamped, the roof panel is not deformed and escaped by the welding heat, and the roof panel is bent, which causes the same inconvenience as described above.

The present invention has been made in view of the above-mentioned problems, and reliably prevents deflection or deformation of a large workpiece when a welding jig is attached, shape defects due to deformation generated during welding, and welding defects, and stabilizes quality. It is another object of the present invention to provide a method for welding large and small workpieces and a device for shortening the welding cycle time and improving the production efficiency.

[Means for solving the problem]

The present invention is configured as follows in order to solve the above problems.

The large work and the small work are respectively positioned and mounted at predetermined positions on the welding jig, the two works are brought into contact with each other, and at least three sides of the large work are positioned and gripped from above and below, thereby holding the small work. After tack welding,
A method for welding large and small workpieces, in which a reference edge of a tack-welded large workpiece is held from below on a welding jig, and the permanent welding is performed from the held edge side.

[Operation] First, the large work and the small work are positioned and supported in a state where they come into contact with each other at predetermined positions on the welding jig for tacking. Temporary welding is to position and grip at least three edges of the large workpiece from above and below by a clamp device.
The fixing is performed on the welding jig for tacking. The large work obtained by tack-welding the small work is transferred to the final welding jig side of the next process by the transfer device. On the final welding jig, only the reference edge of the large workpiece is positioned and gripped from above and below, but the other edges are only supported by the jig from below. In this state, the final welding is performed by the welding device.

As described above, since only the reference edge of the large workpiece is fixed on the permanent welding jig, deformation during welding is reduced, and the large workpiece and the small workpiece are tightly connected to each other, and No defective shape occurs and no defects such as poor welding occur.

〔Example〕

Hereinafter, embodiments according to the present invention will be described with reference to the drawings. In this embodiment, the roof panel W ₂ is used as a large workpiece.
The employed, employing a roof arch W ₁ as small work (7 consists箇member).

FIG. 1 is a plan view showing the entire structure of a roof assembling apparatus including a welding jig and a welding device according to an embodiment, and a transport device for carrying in and out a large work and a small work to and from the welding jig; 1 is a front view taken along the arrow II in FIG. 1, FIG. 3 is a front view explaining the operation of the embodiment in FIG. 2, and FIG. 4 is a front view taken along the line IV-IV in FIG.

As shown in FIG. 1, carried out the roof assembly apparatus with the welding fixture 1 for tacking, the present with a weld fixture 2, the tack welding and the external welding of the roof arch W ₁ and the roof panel W ₂ the welding device 3, a conveyor 4 for transferring Rufuasshi W ₃ which is tack welded to the roof arch W ₁ to the roof panel W _2, a conveying device 5 for transferring the roof arch W ₂ to tack welding jig 1 , Transporting the roof panel W ₂ into the temporary welding jig 1, and transporting the roof assembly W ₃ , which has been permanently welded on the final welding jig 2, to a predetermined payout position. And so on.

 Hereinafter, each component will be described in detail.

As shown in FIG. 1 and FIG. 2, the welding jig 1 for tacking is provided with a base 8 and a roof arch which is erected and fixed on the base 8.
A roof arch mounting tool 9 for supporting each of the W ₁ at predetermined positions and its positioning pins 10, eight roof panel clamping devices 11 mounted on a base 8, and a roof panel W ₂
A pair of roof panel mounts that are erected and fixed on the base 8 to position and support the unclamped edge WR from below.
Consists of 12 mag.

Wherein the edge as a reference of the roof panel W ₂ and WF, when the edge with the edge of the both side surfaces in WS _1, WS ₂ and then edge WF symmetric position with WR, the roof panel clamping device 11 includes sides Edge WF
At two locations and three locations at WS ₁ and WS ₂ respectively with appropriate intervals.

Roof panel clamping device 11, as shown in FIG. 2 to FIG. 4, the post 13 erected from the base 8, the work placing portion 14 supporting the roof panel W ₂ is fixed to the support column 13 from below the predetermined position A clamp member 15 rotatably supported by the support 13 and disposed at a position facing the work mounting portion 14;
A cylinder connected to the clamp member 15 and placed on the base 8
It is composed of 16 mag.

The roof panel mounting device 12 is configured to engage with the edge WR, support the edge WR from below, and hold the position, but may have a structure that simply supports the edge WR from below.

 Next, the fixing welding jig 2 will be described.

As shown in FIG. 1 and FIG. 4, the welding jig 2 for final fixing is a base 8a arranged at the same level position as the base 8, and a roof panel clamp device which is erected and fixed on the base 8a. 11
And roof panel mounting devices 12, 12a.

The roof panel clamp device 11 has the same shape as the roof panel clamp device 11 of the welding jig 1 for tacking, but _two roof panel clamp devices 11 are arranged on the side edge WF serving as a reference of the roof panel W2. Therefore, only the edge WF is positioned and gripped from above and below. Roof panel placement base 12 engages the edge WR of the tack welding of those jig 1 as well as the roof panel W _2, is erected fixed on the base 8a so as to position and support it from below, The roof panel mounting device 12a is also erected and fixed on the base 8a,
Each order to the positioning support from below the edge WS _1, WS ₂ of the roof panel W ₁ is 2箇increments provided.

With the above structure, the roof of the roof arch W ₁ panel W ₂
Tack welded Rufuasshi W ₃ has, along with being positioned gripped from the upper and lower edge WF ₃ as a reference by the roof panel clamping device 11, on the jig is positioned and held from below by the roof panel placement base 12,12a to Will be set.

 Next, the welding device 3 will be described.

As shown in FIGS. 1 to 4, the welding device 3 includes two guide rails 17 disposed in parallel at an appropriate height above the ground and guides that are installed orthogonally between the guide rails 17, 17. It is slidably supported on the rail 18 and disposed.

The configuration includes a first slide base 19 slidably supported by the guide rail 17, a servo motor 20 for moving the first slide base 19 in the direction in which the guide rail 17 is provided,
Second slide table 21 slidably supported by guide rail 18
A servo motor 22 for moving the second slide 21 along the direction in which the guide rails 18 are arranged; a welding tool 23 suspended from the second slide 21 and supported; The welding tool 23 is mounted on a moving table 21 and includes a servomotor 24 for moving the welding tool 23 up and down by a vertical shaft (not shown). It should be noted that the welding tool 23 is configured from a spot welding tool.

With the above configuration, the welding tool 23 is connected to the servomotors 20, 22, 24
Is actuated to move and position at an arbitrary position on the welding jig 1 for temporary attachment and the welding jig 2 for final attachment.

Next, the conveying device 4 for moving the Rufuasshi W ₃ which is tack welded to the roof arch W ₁ to the roof panel W ₂ from tack welding fixture 1 to the position of the attached welding fixture 2.

As shown in FIG. 1, FIG. 2 and FIG. 4, two rails 25 parallel to the direction in which the guide rails 17 are arranged are arranged on the floor on which the bases 8, 8a and the like are placed.

The transport device 4 is movably arranged along the rail 25.

As shown in FIG. 4, a sliding base 26 slidably supported on the rail 25 as shown in FIG. 4, a servomotor 27 mounted on the sliding base 26 and moving it, A guide member 28 also erected on the sliding base 26, and a guide member
A sliding member 29 slidably supported by 28; a cylinder 30 fixed to the sliding base 26 and connected to the sliding member 29 to raise and lower the same; and a rail 25 fixed to the sliding member 29 and A pair of arms 31 extending along the disposition direction, two pairs of pin bodies 32 protrudingly formed on the arms 31, and a positioning protruding from the upper surface of the arm 31 to form a step outside the pin bodies 32. Member 32
And so on.

The positioning member 33 is provided on the margins WS ₁ , WS ₂ of the roof panel W ₂ to lock the stepped portion thereof, and the pin body 32 is positioned on the margins WS ₁ , WS _2. Hole (not shown)
The roof panel W ₂ in what is inserted is for holding in position of the arms 31.

Then, sequentially described conveying device 5, 6, 7 for transferring roof arch W ₁ and the roof panel W ₂ in 1 side welding jig temporarily attached.

First, the conveying device 5 for transferring roof arch W ₁ to 1 side welding jig temporarily attached. For convenience of explanation, the direction in which the guide rails 17 are arranged is defined as the X direction, the direction in which the guide rails 18 are orthogonal to the direction is defined as the Y direction, and the direction perpendicular to the plane of FIG. Provisionally.

A gantry 34 is placed on the floor, and X
A pair of rails 35 are provided along the direction. On the rail 35, a roof arch transport robot 36 is mounted. Further, the stand 34 on which the rail 35 is placed and the welding device 1 for tacking
A pair of sliding rails 37 are fixedly arranged on the base 38 mounted on the floor along the Y direction.

The roof arch transport robot 36 includes a guide member 39 slidably supported by a rail 35, a first base 40 mounted on the guide member 39, and a fixed base mounted thereon and extending along the Y direction. A guide rail 41 linearly connected to the rail 37 and disposed at the same level position, a guide member 42 slidably supported by the guide rail 41, and a second member mounted on the guide member 42;
A base 43, a support member 44 standing upright and placed on the side of the second base 43 on the side of the tacking welding jig 1 (referred to as a front end side);
A servomotor 45 mounted on the rear end side of the base 43 to move the second base 43; and a roof arch set jig 47 fixed to the support member 44 and erected along the Z direction and described later. It comprises a lifting rail 46 that slidably supports the guide member 48, a cylinder 49 for moving the guide member 48, and the like.

Note that a cylinder 50 (FIG. 1) for moving the roof arch transport robot 36 along the rail 35 is fixedly disposed on the gantry 12.

Next, the structure of the roof arch set jig 47 will be described with reference to FIGS.

An arm 51 extending in the Y direction has a base end connected to a guide member 48 and is cantilevered, and a rod (not shown) of a cylinder 49 is connected to the base end. Further, on the arm 51 supporting bar 52 for positioning and supporting the respective members of the roof arch W ₁ in position it is disposed at a predetermined interval and a predetermined level position, an upper end of the support rod 52 roof arch W ₁ of the positioning hole supporting pin inserted into (not shown)
53 is formed to project.

Each welding surface of the support rod 52 roof arch W ₁ which is positioned and supported on on the arm 51 the sealing member is applied. The coating operation is performed by the sealing robot described below.
Performed by 54.

On the floor, there are provided uprights 55 (four in this embodiment as shown in FIG. 1), and at the upper end between the uprights 55, a sliding rail for a sealing robot along the Y direction. 56 is erected. The sealing robot 54 is a base slidably supported on a rail 56 for sliding the sealing robot.
A servomotor 58 mounted on the base 57 and moving the base 57 along the rail 56 for sliding the sealing robot;
Sliding rail for sealing robot fixed to base 57
A guide rail 59 extending along the X direction substantially perpendicular to the arrangement direction (Y direction) of the 56, a base 60 slidably supported by the guide rail 59, and the base 60 mounted on the guide rail 59. The servo motor 61 includes a servo motor 61 that moves along the ceiling, a sealing gun 63 disposed on the lower surface of the base 60, a servo motor 62 that moves the sealing gun 63 up and down, and the like.

Next, a conveying device 6 for transferring roof panel W ₂ at a predetermined position of the tack welding fixture 1.

The transport device 6 has the same structure as the transport device 4 and is provided at a position facing the transport device 4. As shown in FIG. 1 and FIG.
Servo motor 27, guide member 28, sliding member 29, cylinder
30, an arm 31, a pin body 32, a positioning member 33 and the like.

Next, a conveying device 7 for transferring the Rufuasshi W ₃ that the welded roof arch W ₁ to the roof panel W ₂ at a predetermined dispensing position by the first view and Figure 4.

A pair of rails 65 extending along the Y direction are fixed on a gantry 64 mounted on the floor. The tip of the rail 65 extends to the vicinity of the final welding jig 2. On the rail 65, a slide base 66 slidably supported by the rail 65 is mounted. A support member 67 erected in the Z direction and a servomotor 68 for moving the slide base 66 along the rail 65 are mounted on the slide base 66. A guide member 70 is slidably supported by a guide rail 69 fixed to the support member 67, and a base end of an elevating arm 71 extending in the Y direction is fixed to the guide member 70. Also,
The tip of the rod 73 of the cylinder 72 fixed to the support member 67 is connected to the lifting arm 71.

On the elevating arm 71, a support rod 75 provided with a pin 74 at the tip is erected and fixed. Pin 74 and support rod 75 is intended to position and support the roof arch W ₁ of Rufuasshi W _3, in the embodiment abuttingly engages the member disposed on the cutting edge and the end edge of the roof arch W _1.

Will now be described in detail with reference to the accompanying drawings the effect and operation of the present embodiment, the conveying device 5, 6 and the external welding already transferring roof arch W ₁ and the roof panel W ₂ to tack welding jig 1 transporting device 7 for transferring the Rufuasshi W ₃ in dispensing position is also the roof assembly illustrating the entire apparatus acts and operations, including.

As a process of the assembling method by the roof assembling device,
It consists of six steps. That is, a roof arch setting step of setting the roof arch W ₁ at a predetermined pool location on the transport device 5 and transferring the roof arch W ₁ to a position where the roof arch W ₁ can be put into the welding jig 1 for tacking. and the roof arch sealing step of applying the sealing member to the welding position of welding before the roof arch W _1, was placed in tack welding jig 1 as well as set on the conveying device 6 roof panel W ₂ from the pool location a roof panel setting step of positioning the obtained position, the roof panel roof arch tacking step of tack welding the on and the positioned roof arch W ₁ and the roof panel W ₂ to tack welding jig 1,
The method includes a roof panel / roof arch permanent attaching step for final welding the roof assembly transferred into the final welding jig, a roof assembly dispensing step for transferring the final welded roof assembly to a dispensing position, and the like.

The operation and operation in each of the above steps will be described below.

As shown in FIG. 1, the roof arch W ₁ is once brought to a predetermined pool location and actuated cylinder 50, along the entire roof arch transfer robot 36 of the transfer device 5 to the rail 35 X
Moves in a direction to position the arm 51 to the lower roof arch W _1. Place the roof arch W ₁ on the respective support rod 52 on the arm 51 as shown in Figure 2, to position the roof arch W ₁ by inserting the support pin 53.

Next, the roof arch carrier robot 36 advances upward view of Figure 1 along the X direction, and operates the servo motor 49, as it is inserted into the roof arch W ₁ to the weld fixture 1 side for tacking Set to the position and height to get. Next, the servomotors 58 and 61 of the sealing robot 54 are operated to move the base 57 and the base 60 along the guide rails 56 and 59, and move the sealing gun 63 to the respective roof arches W _1.
And a moving and positioning the welding point, applying the sealing member while close to sealing gun 63 to the roof arch W ₁ to operate the servo motor 62 to the welding point.

Next, the servo motor 45 is operated to advance the roof arch transport robot 36 in the Y direction along the guide rail 41 and the slide rail 37 linearly connected thereto, and the arm 51
And the roof arch W ₁ positioned and supported on it
Is inserted into the welding jig 1 for tacking.

On the other hand, the roof panel W ₂ carried to the pool location is placed on the arm 31 of the transfer device 6, as shown in FIG. 1, the pin 32 is inserted while being sandwiched between the stepped portion of the positioning member 33, It is positioned at a predetermined position. Operating the cylinder 30, to operate the servo motor 27 together with the lifting arm 31, along the rails 25 to move the entire conveying device 6 in the X direction, the arm 31 and the temporary positioning supported roof panel W ₂ thereon It is inserted into the welding jig 1 for attachment.

Next, the servo motor of the roof arch transport robot 36
The arm 51 inserted into the tacking welding jig 1 by operating the 49
Each roof positioning pin 10 with a put on the first figure tack welding the roof arch jig 1 of each of the roof arch W ₁ is lowered along the Z direction as indicated placement base 9 Arch W ₁ inserted for positioning on the jig of the roof arch W ₁ within. When the third roof arch W ₁ as shown in FIG pass over the roof arch placement base 9, the servo motor 45 is actuated, the arm 51 is retracted along the Y direction, tack welding jig 1 Return to the original position away from.

Cylinder 30 of the conveying device 6 as shown in Figure 3 operates at the same time, the roof panel W ₂ arm 31 is lowered is engaged abutting engagement to the roof arch W _1, it is held on the roof arch W _1. Its roof panel W ₂ as state shown in Figure 3 is supported from below the edge WF and WS _1, WS ₂ on the work mounting portion 14 of the roof panel clamping device 11, the roof panels placed the edge WR It is supported from below by the tool 12 and positioned at a predetermined position. Cylinder 16 is actuated in the roof panel clamping device 11, and the clamp member 15 is rotated, the roof panel W ₂ is gripped from above and below by the clamp member 15 and the work placing portion 14 is fixed in place. Operates the servomotor 27 of the transfer device 6 is in this state, the entire conveying device 6 is retracted along the X-direction, the arm 31 is disengaged from the roof panel W _2, the original position away from the tack welding jig 1 Return to.

When the roof arch W ₁ and the roof panel W ₂ is positioned and fixed on the tack welding jig 1, the servo motor 20 and servo motor 22 of the welding device 3 is operated, the first sliding base
19 and the second slide 21 move along the guide rail 17 and the guide rail 18, and move and position the welding tool 23 to the welding location. At this point, the servo motor 24 is operated, and the welding tool 23
It is elevation and performs tack welding of the roof arch W ₁ and the roof panel W _2. Roof panel W ₂ is 3 edge WF by the roof panel clamping device 11, WS _1, WS ₂ and has been positioned gripped from above and below, even if caused some deflection to the roof panel W ₂ for the tack welding roof arch W ₁ denotes a roof panel
It is possible to weld without difficulty to W _2.

When the tack welding is completed, the transfer device 4 that has been waiting outside the tack welding jig 1 operates, and the arm 31 advances in the X direction and is inserted into the tack welding jig 1.

Positioning member having a step on the arm 31 of the transfer device 4
For 33 and the pin member 32 is provided, inserting the pin 32 into the positioning holes in the roof arch W ₁ with Rufuasshi W ₃ completing the stepped welding is sandwiched between the stepped portion of the positioning member 33 And is held on the arm 31. Transport device 4
Raises the arm 31 actuates the cylinder 30 of the servo motor 27 operates in a state of being detached Rufuasshi W ₃ from the jig, is retracted along the entire conveying device 4 in the X direction, provisionally the Rufuasshi W ₃ It is taken out from the attachment welding jig 1 and transferred to the final attachment welding jig 2.

Rufuasshi W ₃ being on the assigned welding jig 2, the edge WF to the reference while being positioned gripped from above and below by the roof panel clamping device 11, the other edge WS _1, WS
_{2. The} WR is positioned and supported by the roof panel mounting devices 12a and 12 from below. In this state, the welding device 3 moves along the guide rails 17 and 18, and
23 is moved to a predetermined welding position. Here, the permanent welding is performed.

The final welding is performed from the edge WF side gripped by the roof panel clamp device 11, and the thermal deformation caused by the final welding is released to the freely supported edge WR side to prevent or reduce the occurrence of thermal deformation. It is desirable to do so. That is, unlike the case of the tack welding, the final welding is performed so that the edges WS ₁ , WS ₂ , and WR are kept substantially free except for the reference edge WF, so that deformation due to welding is reduced, Rufuasshi with W ₃ of defective shape can be prevented, so that the welding defect can be reliably prevented.

When the final welding is completed, the transfer device 7 that is waiting at a position away from the final welding jig 2 operates. That is, as shown in FIG. 4, when the servo motor 68 of the transfer device 7 operates, the entire transfer device 7 advances in the Y direction along the rail 65, and the elevating arm 71 is moved into the welding jig 2 for permanent attachment. is inserted is positioned below the Rufuasshi W _3. Here operates the cylinder 72, the lifting arm 71 is raised, the support rod 75 and the pin 74 on the lifting arm 71 for positioning support Rufuasshi W _3. The entire conveying device 7 as shown in FIG. 1 in this state is moved backward along the Y direction, remove the Rufuasshi W ₃ from the attached welding fixture within 2 is moved to a predetermined payout position pays out.

With the above, the roof assembly welding work has been completed.
The same is repeated.

In this embodiment, the roof panel W _{2 is used} as a large workpiece.
Is adopted, is adopted roof arch W ₁ as an accessory work, not intended to be limited to such. Of course, it is natural to change the shape of the support tool, the mounting tool, the clamp device, etc. according to the shape of the large work and the small work.

Further, the structures of the transfer devices 5, 6, 7 and the welding device 1 for temporary attachment and the welding device 2 for permanent attachment are not limited to only the embodiment, and a technique that exerts the same function is applied.

〔The invention's effect〕

Since the present invention is configured as described above, the following effects can be obtained.

a) Since the tacking welding jig for positioning and holding at least three edges of the large workpiece from above and below only performs the tack welding of the small workpiece, the large workpiece is bent by the tacking welding jig due to a dimensional error. However, since the permanent workpiece is welded to the large workpiece by a permanent welding jig for positioning and gripping only the edge serving as a reference for the large workpiece from above and below, the workpiece does not have a shape defect.

b) The large workpiece and the small workpiece are permanently welded on the final welding jig. However, in the final welding jig, only the reference edge of the large workpiece is positioned and gripped from above and below, and the other edges are Since the structure only supports from the lower part, thermal deformation generated at the time of welding is alleviated, and the large work and the small work are easily welded to each other.

c) Since the welding process is divided into two processes, tack welding and actual welding, the cycle time required for welding is reduced.
Production efficiency can be improved.

d) The transfer device is configured to enter and exit the welding jig to input the large work and the small work. After the input, the transfer device returns to the original position. Can be done. Therefore, there is no idle time in the process, and the production efficiency can be improved.

e) Final welding is performed from the side of the edge where the large workpiece is held. For this reason, the thermal deformation caused by the permanent welding can be released to the side of the edge that is freely supported, and the occurrence of the thermal deformation can be prevented or reduced.

[Brief description of the drawings]

1 to 4 of the drawings relate to an embodiment of the present invention, and FIG. 1 shows a welding jig and a welding device, and a transfer device for carrying in and out a large work and a small work to and from the welding jig. FIG. 2 is a plan view showing the entire structure of the roof assembling apparatus including FIG. 1, FIG. 2 is a front view taken along the arrow II of FIG. 1, FIG. Is IV- in Fig. 1.
FIG. 4 is a front view as viewed from an arrow IV. FIG. 5 is a plan view showing the entire structure of a conventional roof assembling apparatus. W ₁ … Roof arch, W ₂ … Roof panel W ₃ … Roof assembly 1… Temporary welding jig 2 …… Fixing welding jig 3 …… Welding equipment 4,5,6,7… … Conveying device 8,8a, 57,60… Base 9… Roof arch mounting device 10… Positioning pin 11… Roof panel clamping device 12,12a… Roof panel mounting device 13,55… Post 14 Workpiece mounting part, 15 Clamp member 16, 30, 49, 50, 72 Cylinder 17, 18, 41, 59, 69 Guide rail 19 First slide table 20, 22 , 24,27,45,58,61,62,68 ... servo motor 21 ... second slide table, 23 ... welding tool 25,35,65 ... rail 26,66 ... slide base 28, 39, 42, 48, 70 ... Guide member 29 ... Sliding member, 31, 51 ... Arm 32 ... Pin body, 33 ... Positioning member 34, 38, 64 ... Stand 36 ... Roof arch Transfer robot 37 ... Sliding rail, 40 ... First base 43 ... Second base 44,67 ... Support member 46 ... Lifting rail 47 ... Roof arch set jig 52, 75 ... Support rod, 53 ... Support pin 54 ... Sealing robot 56 ... Sliding rail, 63 ... Sealing gun 71 ... Lifting arm, 73 ... Rod 74 ... pin

────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification symbol FI B23K 37/04 B23K 37/04 H (56) References JP-A-1-224171 (JP, A) JP-A 64-28081 ( (JP, A) Japanese Utility Model Showa 55-46097 (JP, U) (58) Fields investigated (Int. Cl. ⁶ , DB name) B23K 9/00 501 B23K 31/00 B23K 37/00, 37/04

Claims (1)

(57) [Claims] 1. A large workpiece and a small workpiece are positioned and mounted at predetermined positions on a welding jig, and the two workpieces are brought into contact with each other, and at least three edges of the large workpiece are positioned and gripped from above and below. After the small workpiece is tack-welded, the permanent welding is performed from the side of the held edge while holding the reference edge of the tack-welded large workpiece on the welding jig from below. Welding method for large and small workpieces.