JP3189359B2 - Structure assembly method and apparatus - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is used when the assembly of a side structure and a roof structure of a passenger car body is performed by resistance spot welding.

[0002]

2. Description of the Related Art A vehicle body comprises a hexahedron having an underframe serving as a floor, a roof, a side structure extending in the longitudinal direction of the vehicle body, and an end structure at an end in the longitudinal direction of the vehicle body.

With regard to the combination of the side structure and the roof, the two are temporarily welded and then moved to a welding work place, a large spot welding gun is hung upward, and is manually inserted from the window or the entrance of the side structure into the spot. We are doing by welding. A technology in which a spot welding gun is mounted on a truck and automated is disclosed in “Welding Technology” December 1989 (Sanho Publishing Co., Ltd.).

[0004]

The connection between the side structure and the roof structure is performed by resistance spot welding. However, in the conventional spot welding method, an assembly positioning facility and a spot welding facility are provided respectively. Assembling and positioning equipment combines the side structure and the roof to perform positioning and partial welding,
Next, this structure was moved to another welding place and welded.
Since the welding equipment inserts a large gun through a window or an entrance and performs welding, it is necessary to perform a complicated operation, which is large and expensive.

An object of the present invention is to integrate an assembling / positioning facility and a spot welding facility to shorten the production line, reduce the number of production steps, and reduce the equipment cost.

[0006]

SUMMARY OF THE INVENTION According to the present invention, a roof structure is placed on a pair of upright side structures, and then, in that position, a longitudinal portion of the structure is provided outside an overlapping portion between the side structure and the roof structure. A long holding metal is arranged in the direction in the direction, and then the electrode is moved from the inside toward the holding metal and spot welding is performed.

[0007]

When the side structure and the roof structure are overlapped, spot welding is performed in that case. In this case, a press fitting long in the longitudinal direction of the structure is disposed close to the outside of the overlapping portion to form a positioning seat. The electrode protrudes from the inside to the press fitting, and spot welding is performed.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described with reference to FIGS. This equipment includes the side structures 10, 10 of the structure, the roof structure 2
0, and a facility for assembling the wife structures 30, 30 to produce the structures. Side structure 10, roof structure 20, wife structure 30
Is known, and has a bone member inside.
The upper end of the side structure 10 is located inside the roof structure 20 at the widthwise end of the roof structure 20. Both overlap in a vertical plane.

The equipment includes fixing devices 50, 50 for determining the position of the lower end of the side structure 10, and positioning and resistance spot welding of the overlapping portion (upper end of the side structure 10) between the side structure 10 and the roof structure 50 from inside and outside. And a device for performing the same.

The fixing devices 50, 50 are arranged horizontally and parallel substantially along the longitudinal direction of the vehicle body. The fixing device 50 is a device that supports the lower end of the side structure 10 and sandwiches it from both sides in the horizontal direction. The fixing device 50 corresponds to the shape of the lower end of the side structure 10. The fixing device 50 is a side structure 10.
Can be opened and closed so as to sandwich the lower end of the.

[0011] Positioning and spot welding comprises a first device 60, 60 located outside the structure and a second device 70 located inside the structure.

A holding member 61 at the tip of the first device 60 is located at a height of an overlapping portion between the side structure 10 and the roof structure 20. The presser fitting 61 can contact the vertical portion of the roof structure 20. The presser fitting 61 is disposed horizontally along the longitudinal direction of the vehicle body, and is equal to the length of the structure. That is, the holding metal 6
One length is equal to the required area of spot welding. The shape of the presser fitting 61 in the longitudinal direction substantially matches the shape of the vertical portion of the roof structure 20. That is, if the vertical portion is a straight line along the longitudinal direction, the surface of the holding member 61 on the roof structure 20 side is a straight line along the longitudinal direction.

The holding member 61 is provided with a plurality of extension devices (for example,
It can be moved in the horizontal direction by an electric screw rod type) 63. The telescopic device 63 is installed above a column 67 installed along the longitudinal direction of the vehicle body. A work sidewalk 68 is provided at the upper end of the pillar 66. The holding member 61 is a member to be one electrode of resistance spot welding and is made of copper.

The second device 70 located inside the structure includes:
It has the holding metal fittings 71 and 71 corresponding to the holding metal fittings 61 and 61. The holding member 71 is installed at the same height position as the holding member 61. The presser fittings 71, 71 are mounted on a carriage 75 via expansion and contraction devices (for example, air cylinder type) 73, 73. The expansion / contraction device 73 moves the holding member 71 in the horizontal direction. The cart 75 is provided with the telescopic devices 7 on both sides in the width direction.
3,73 are installed. The carriage 75 moves along the longitudinal direction of the structure along a rail 77 installed horizontally at the upper end of the plurality of columns 77.

The holding member 71 is to be the other electrode of the resistance spot welding and is made of copper. Holder 71 is 1
One extension device 73 is provided. Therefore, one carriage 75 is provided with one presser fitting (electrode) 7 on each of the left and right sides.
One. At least two trolleys 75 are provided on one rail. The bogie 75 is provided with an electric device 76 for resistance spot welding including a welding transformer and the like. The electrodes 61 and 71 and the electrical equipment 76 are connected in a known manner so as to be spot weldable.

Next, a procedure for assembling and welding the structure will be described with reference to FIG. First, as is well known, the side structures 10, 10, the roof structure 20, and the wife structure 30 are manufactured in another place.

First, the wife structure 30 is suspended by an overhead crane and fixed at a predetermined position of the facility (positions at both ends in the longitudinal direction of the structure). The lower end of the wife structure 30 is another fixing device 50.
Fix with. In addition, the positioning is performed by disposing a fixing rod (stay) obliquely with respect to the vertical plane so that the wife structure 30 does not tilt (step S10).

Next, the upper part of the side structure 10 is lifted by an overhead crane and carried into the facility. The lower end of the side structure 10 suspended by the overhead crane is inserted into the fixing device 50, and the fixing device 5
Fixed at 0. Next, the wife structures 30, 30 and the side structures 10,
The overlapped portion with 10 is temporarily attached by arc spot welding which can be performed from the outside. Thereby, the side structure 10 is positioned. The carts 76, 76 are still arranged at positions that support the inside as shown in FIG. Each trolley 7
The 6 holding members 71 are used as positioning members. At this time, in order to facilitate the lowering of the roof structure 20, the holding metal 7
The front end position of the pair 1 is located 5 to 15 mm inside so as to be inside the interval between the pair of regular side structures 10, 10. When the bending structure of the side structure 10 is weak, the side structure 10 is supported by projecting a stay from the column 77 or providing a stay in the expansion / contraction device 73. When the side structure 10 is bent outward, the side structure 10 is supported by a stay provided on the column 67 or a telescopic device (neither is shown) (steps S20 and S30).

Next, the roof structure 20 is suspended and carried by the overhead crane, placed on the structural body 10 and the wife structure, and the vertical portions at the ends are overlapped. (Step S40).

Next, the telescopic device 6 of the outer first device 60 is used.
3 to drive the presser fitting 61 (step S5).
0).

Next, the telescoping device 73 is driven to hold the holding member 7.
1 and projecting the roof structure 20 between the holding members 61 and 71.
And the side structure 10 is sandwiched, and spot welding is performed using a welding transformer (step S60). This is the provisional attachment of the side structure 10 and the roof structure 20.

Next, the presser fitting (electrode) 71 is retracted, and the two carriages 76 are moved to substantially the center of the structure in the longitudinal direction (step S70).

While moving toward the vehicle end, the telescopic device 73 and the welding transformer are driven to perform spot welding at predetermined intervals (for example, at intervals of several cm) (step S8).
0). This improves the balance of welding heat input,
The deformation of the structure can be reduced. The expansion and contraction of the expansion and contraction device 73, the driving of the welding transformer, and the driving of the carriage 76 are automatically controlled by a control device in the electric device 76. For example, roof structure 2
Since the position where spot welding is required by overlapping the 0, the side structure 10, and the three branches of the bone member is known in advance, the current value or the like is controlled at that position. The cart 75 includes a position detecting means (for example, a pulse encoder) and can detect the position.

Next, the overlapping portion between the side structure 10 and the wife structure 30 and the overlapping portion between the roof structure 20 and the wife structure 30 are joined by an arc spot welding method or the like (step S90). This coupling means may be a rivet.

Next, this structure is lifted by an overhead crane and carried into a place where it is assembled with an underframe.

In the above embodiment, one welding transformer is provided for the two electrodes 71, 71, but one welding transformer is provided for each electrode, so that the reactive current can be reduced.

In the above embodiment, the holding member 61 is an electrode. However, the holding member 61 is simply a holding member (seat), and the holding member 71 is
One electrode and indirect welding may be used. Also,
The presser fitting 71 may be an electrode of an arc spot welding method.

The spot welding current flows through the welding transformer, the conductor 81, the holding member 71, the side structure 10, the roof structure 20, the holding member 61, and the conductor 82. As described above, since the current path is long and the impedance becomes large in an alternating current, a direct current is used.

It should be noted that one electrode 71 is connected to one expansion device 73.
Although only two electrodes are provided, about two electrodes may be provided.

As described above, the fixed electrode 6 is provided outside the structure.
1 is arranged and the electrode 71 is pressed from the inside to the outside of the structure to perform spot welding, so that spot welding can be performed while positioning the structure. Therefore, man-hours for assembly and welding can be reduced, and the dimensional accuracy of the vehicle body can be improved.

Further, since the longitudinal direction of the structure is linear, the holding metal 61 as an electrode can be made linear and inexpensive, and can be effectively used for positioning. On the other hand, the number of the holding metal members 71 as the other electrode is one (the number is small even if it is plural), so that the welding transformer can be made small, and even if the thickness of the structure is different, it can be easily handled.

FIG. 3 shows an embodiment in which the underframe 30, the side structure 10,
Dolly 7 for spot welding of the structure consisting of roof structure 20
5a travels. After the rail 85 and the cart 75a are installed on the underframe 30, the side structure 1
0 and 10 are fixed to the underframe 30. A lifter 86 that moves up and down is installed between the carriage 75a and the expansion and contraction devices 73 and 73a. The lifter 86 facilitates the movement of the carriage 75a.

[0033]

According to the present invention, since the assembly of the side structure and the roof structure and the spot welding can be integrated, the production line can be shortened, the number of manufacturing steps can be reduced, and the equipment cost can be reduced.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of one embodiment of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG. 2;

FIG. 3 is a flowchart of one embodiment of the present invention.

FIG. 4 is a longitudinal sectional view of another embodiment of the present invention.

[Explanation of symbols]

10: side structure, 20: roof structure, 30: underframe, 61, 7
DESCRIPTION OF SYMBOLS 1 ... Holder, 63, 73 ... Telescopic device, 75 ... Dolly, 7
8 ... Rail.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-54-113115 (JP, A) JP-A-60-50065 (JP, A) JP-A-62-234775 (JP, A) JP-A-2- 193760 (JP, A) Japanese Utility Model Showa 58-104762 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) B61D 17/00

Claims (6)

(57) [Claims] 1. A roof structure is superimposed on a pair of standing side structures, and then, at that location, a long holding metal fitting in the longitudinal direction of the structure is placed outside the overlapping portion between the side structure and the roof structure. And then spot-welding the electrode from the inside toward the presser fitting side and performing spot welding. 2. The structure according to claim 1, wherein said spot welding is performed at a central portion in the longitudinal direction of the structure, and then the spot welding position is sequentially moved toward an end portion in the longitudinal direction. Assembly method. 3. A plurality of longitudinally positioned pairs of side structures are supported by electrodes for spot welding, and then the roof structures are stacked on the pair of side structures. Placing a presser fitting long in the longitudinal direction of the structure close to the outside of the overlapping portion of the side structure and the roof structure, and then spot welding while moving the electrode from the inside toward the presser fitting side, A method of assembling a structure characterized by the above-mentioned. 4. A pair of wive structures located at both ends in the longitudinal direction of the structure are erected, and then a pair of side structures are disposed between the wive structures, and the overlapping portions of the wive structures and the side structures are joined. Then, on that spot, a presser fitting that is long in the longitudinal direction of the structure is arranged close to the outside of the overlapping portion of the side structure and the roof structure,
A method for assembling a structure, comprising: moving an electrode from the inside toward the presser fitting; and performing spot welding. 5. A horizontal rail provided along the longitudinal direction of the vehicle, a bogie moving along the rail, mounted on the bogie, and installed on both sides in the width direction of the bogie, in the width direction. And a presser fitting which is installed at the height of the electrode, is movable in the horizontal direction in opposition to the electrode, and is long along the longitudinal direction of the vehicle. apparatus. 6. The assembly apparatus according to claim 5, wherein a plurality of the carriages having the electrodes are provided on the rail.