JPH0341904Y2 - - Google Patents

Description

[Detailed description of the invention] (Field of industrial application) The present invention relates to a welding device for assembling a vehicle body by welding workpieces such as the rear body panel of a truck, and in particular, the present invention relates to a welding device for assembling a vehicle body by welding workpieces such as the rear body panel of a truck. It is designed to be weldable.

(Prior Art) Automobile bodies are assembled by welding a plurality of panels, and in order to assemble the rear body panel of a truck body, an assembly jig as shown in Fig. 5 has traditionally been used. It's summery.

As shown in the figure, the conventional assembly jig 1 includes a jig base 3 having wheels 2, and a work support member 4 made of locating pins, receiving posts, etc., fixed to the jig base 3. With the workpiece supported and positioned on the workpiece support member 4, an operator (not shown)
A PSW (portable spot welder), a portable spot welder, is used to perform spot welding at designated locations to assemble the vehicle body. The gun of the PSW is suspended by a balancer attached to a monorail on the ceiling of the factory building, and the jig base 3 can be easily moved as the welding work progresses.

(Problem to be solved by the invention) However, in such conventional car body assembly, a plurality of rear body panels are each placed on the jig base 3, and one or two workers are required to assemble the rear body.
By operating the PSW, we perform multi-point spot welding, so as the number of produced vehicles increases, and the number of each vehicle type increases,
Even if the workpiece support member 4 of the jig base 3 is shared by multiple vehicle models, there is a problem in that the productivity of vehicle assembly decreases.

In addition, if the jig base 3 was manufactured for each vehicle model, the production cost of the vehicle would be high, and the welding quality would be affected by the skill level of the worker.
There was a problem in that it was difficult to ensure stable welding quality.

The present invention was developed in view of the above-mentioned problems of the conventional technology, and by repeating the positioning movement of moving the workpiece to position a predetermined part and the welding operation in a clamped state, it is possible to avoid expensive welding. The purpose is to automatically weld and assemble multiple types of workpieces without using a robot.

(Means for Solving the Problems) The present invention for achieving the above object includes a lower base, columns erected on the lower base at a predetermined distance from each other, and columns fixed to the upper ends of these columns. A conveyor for guiding a cart on which a work is placed is arranged to pass through the inside of the mount, and is engaged with the cart to move the work on the cart in a direction along the conveyor. a positioning means for positioning the workpiece is disposed adjacent to the conveyor, and a plurality of pairs of clamp cylinders attached to the lower base and the upper base and configured to clamp the workpiece respectively are arranged in the moving direction of the workpiece. A plurality of pairs of spot welders are arranged in a direction perpendicular to the movement direction of the workpiece, and are attached to the lower base and the upper base, and are paired with each other and weld the workpiece respectively. The welding apparatus is characterized in that the welding apparatus is arranged to perform welding work on a plurality of types of workpieces by transporting the workpieces by the trolley and welding by the spot welding machine.

(Function) The welding position of the welding machine attached to the frame with respect to the workpiece is determined by moving the cart on the conveyor with the workpiece placed on the cart. At this position, the workpiece is positioned by the positioning means and clamped by a clamp cylinder attached to the pedestal. In this state, the welding machine moves forward toward a predetermined part of the workpiece, and the electrodes of the welding machine are pressed against both sides of the workpiece to perform welding work. Next, the workpiece is transported to position other parts to the welding machine, and after stopping at a predetermined position, the workpiece is clamped by a clamp cylinder and continues to be welded to other parts by the welding machine. work is done. In this way, the transport and positioning movement of the workpiece and the welding operation in the stopped state are repeated, and the welding operation for one workpiece is completed. When the type of workpiece is changed, simply change the stop position of the workpiece by changing the feed pitch of the cart.
Welding operations are similarly accomplished at predetermined locations.

(Example) Hereinafter, the present invention will be explained based on the drawings. 1st~
Figure 4 is a diagram illustrating an embodiment of the present invention, and the base 1
As shown in FIG. 1, a roller conveyor 12 is installed on a stand 11. This roller conveyor 12 has two parts as shown in FIGS.
The ski carts 13 shown in FIG. 4 are placed on the roller conveyor 12 in rows.

As shown in FIG.
It has two parallel base members 14 that move on a row of roller conveyors 12, a beam member 15 spanned between these base members 14, and a work support consisting of a locate pin, a receiving post, etc. A member 16 is attached to the ski trolley 13. A plurality of sets of workpiece support members 16 are attached to the ski cart 13 so that workpieces of a plurality of vehicle types can be supported. Incidentally, the member designated by the symbol W in FIG. 4 is a part of the workpiece constituting the rear body of the truck. roller conveyor 12
A guide plate 17 that contacts the base member 14 of the ski truck 13 is fixed to the inside of the ski truck 13, and the ski truck 13 moves on the roller conveyor 12 while contacting this guide plate 17. A stop plate 19 is fixed to the base member 14 of the ski cart 13 in parallel with the base member 14 by a coupling member 18, and each stop plate 19 has a plurality of locking plates corresponding to the types of workpieces. A hole 20 is bored.

The roller conveyor 12 has a lower base 21 located below it and fixed to the base 10, two columns 22 fixed to the lower base 21 and located on both sides of the roller conveyor 12, and a lower base 22 located on the upper part of these columns 22. A pedestal 24 comprising an upper base 23 fixed to the upper base 23 is installed so as to straddle the roller conveyor 12.

Oil-less metal guides 25 and 26 are attached to the upper surface of the lower base 21 and the lower surface of the upper base 23 of the mount 24, respectively, and sliding bodies 27 and 2 slide along the respective guides 25 and 26.
8 is attached to the upper base 23 and the lower base 21 so as to be movable laterally with respect to the roller conveyor 12. As shown in FIG. 3, the sliding bodies 27 and 28 are movable by shift cylinders 29 and 30 attached to the upper base 23 and lower base 21, respectively. A welding gun 3 having an electrode tip 31 for spot welding is mounted on each of the sliding bodies 27 and 28.
2 and 33 are fixed. These welding guns 32, 33 have cylinders, and the electrode tip 31 can move forward and backward.

The electrode tip 31 of the welding gun 32 is energized from a multi-transformer 35 attached to the lower base 21 via a bracket 34, and the welding gun 3
The third electrode chip 31 is supplied with electricity from a multi-transformer 37 attached to the upper base 23 via a bracket 36. In the figure, energizing cables connecting each multi-transformer 35, 37 and electrode chip 31 are not shown, and hoses that guide cooling water for cooling each electrode chip 31 are also not shown. .

Furthermore, as shown in FIG. 3, clamp cylinders 42 and 43 having clamp pieces 40 and 41 for clamping a workpiece are attached to the lower base 21 and the upper base 23.

As shown in FIGS. 2 and 3, a lock pin 45 is attached to the column 22 of the pedestal 24 so that it can be moved forward and backward toward the roller conveyor 12 by a lever 44. This lock pin 45 is attached to the ski trolley 1.
The ski cart 13 is fitted into a hole 20 drilled in the stop plate 19 of No. 3, thereby locking the ski cart 13 on the roller conveyor 12.

Next, an explanation will be given of an assembly procedure when assembling a rear body floor of a truck by welding a plurality of panels using the above-mentioned vehicle assembly apparatus.

First, after placing a workpiece (not shown) on the ski cart 13 shown in FIG.
is moved on the rollers of the roller conveyor 12 toward the frame 24. At this time, the operator operates the lever 44 shown in FIG. 2 to pull the lock pin 45, and then releases the lever 44. Then, the lock pin 45 is moved to the stop plate 19 by the elastic force of a spring (not shown) applied to the lock pin 45.
It is like sliding on the surface.

When the ski truck 13 moves further forward, the lock pin 45 is inserted into the hole 20 formed in the stop pullout 19, and the ski truck 20 is positioned at a predetermined position and stopped. Thereby, the welding position of the workpiece is positioned between the electrode tips 31 of the welding guns 32 and 33. In this state, by turning on the start button 46 shown in FIG. 2, the upper and lower clamp pieces 40, 41 hold down the workpiece. The forward limit of each clamp piece 40, 41 is detected by a limit switch LS1 shown in FIG.

Next, the welding guns 32 and 33 are operated to apply pressure and current to the workpiece using the electrode tip 31 to perform spot welding, and then the electrode tip 31 is separated from the workpiece. After performing spot welding at the predetermined positions in this way, the shift cylinders 29 and 30 are driven to move the sliding bodies 27 and 28 onto the roller conveyor 12.
The welding guns 32 and 33 perform spot welding again at a different position on the workpiece. The shift positions of the sliding bodies 27 and 28 at this time are determined by the limit switch shown in FIG.
Detected by LS2. After that, the clamp cylinders 42 and 43 are driven to separate the clamp piece 40 from the workpiece.

When the spot welding work at a predetermined position is completed in this way, the lever 44 is operated to pull the lock pin 45, the ski cart 13 is moved on the roller conveyor 12, and the workpiece is moved to the next welding position on the ski cart. 13. Thereafter, spot welding is performed on the workpiece in the same manner as described above. When all the spot welding work is completed, the workpiece assembly work is completed, and the lock pin is pulled out by operating the lever 44, and the ski cart 13 is advanced to the left in Fig. 1.
The workpiece is taken out from the ski cart 13 using a lift device, air hoist, etc. (not shown).

After the workpiece has been removed, the ski cart 13 is moved to the right in FIG. 1 and is placed on standby for the next welding operation.

(Effects of the invention) As described above, according to the invention, the positioning of the welding part on the workpiece by transporting the workpiece using a trolley, and the welding operation on the workpiece in a state where it is clamped at the positioning position are performed on one workpiece. Since welding is performed repeatedly over a single workpiece, a single workpiece can be welded at a large number of locations without using an expensive welding robot to move the spot gun in three-dimensional directions. In addition, since the welding machine is mounted on a stand, it is possible to ensure stable welding quality compared to when an operator carries out welding work by holding the welding machine, and productivity is improved and high quality is achieved. products. Furthermore, by changing the feeding pitch of the cart, it is possible to assemble and produce a plurality of types of workpieces using one device. Furthermore, since the structure is simple, even if the type is changed, the assembly device can be used as is by simply changing the mounting position of the welding gun, making it possible to reduce equipment costs.

[Brief explanation of drawings]

Fig. 1 is a front view showing a car body assembly device according to an embodiment of the present invention, Fig. 2 is a plan view of Fig. 1, Fig. 3 is a left side view of Fig. 1, and Fig. 4 shows a truck. The perspective view and FIG. 5 are front views showing a conventional vehicle body assembly jig. 12...Roller conveyor, 13...Dolly, 16
... Work support member, 24 ... Frame, 31 ... Electrode chip, 32, 33 ... Welding gun, 40, 4
1... Clamp piece, 42, 43... Clamp cylinder.

Claims (1)

[Scope of utility model registration request] A lower base, columns erected on the lower base at a predetermined distance from each other, and an upper base fixed to the upper ends of these columns form a pedestal to guide a cart on which a work is placed. A conveyor is disposed so as to pass through the inside of the frame, and a positioning means that engages with the carriage and positions the workpieces on the carriage in a direction along the conveyor is disposed adjacent to the conveyor, and the lower base and the A plurality of pairs of clamp cylinders are attached to the upper base and are arranged in a direction perpendicular to the moving direction of the workpiece, and are arranged in a direction perpendicular to the moving direction of the workpiece, and are attached to the lower base and the upper base. A plurality of pairs of spot welding machines for welding the workpieces are arranged in a direction perpendicular to the moving direction of the workpieces. A welding device characterized in that it can perform welding work on different types of workpieces.