JPH0328266B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a vehicle body welding assembly line.

(Prior art) Generally, an automobile body welding assembly line is equipped with a plurality of welding stations arranged in series along the transport direction of the car body, and each welding station welds a predetermined position of the transported car body. By doing so, they are now able to assemble the car body.
In order to automatically perform this welding work by a robot, each welding station must position the car body at a predetermined position prior to welding by the robot. For this reason, each welding station is equipped with a positioning unit. It is provided.

Traditionally, this positioning unit has been installed directly on the floor of the welding line, so if it becomes necessary to replace the entire positioning unit due to a car model change, for example, the old positioning unit must be removed first. After leveling the floor, a new positioning unit was installed. However, when replacing the old and new positioning unit in this way, it is necessary to remove the old positioning unit, level the floor, and install the new positioning unit, but each of these tasks requires a considerable amount of work. Due to the laborious, time-consuming and costly process, replacing the positioning unit as a whole has resulted in a fairly long period of time and a very high cost.

(Object of the Invention) The present invention has been made in consideration of the above-mentioned circumstances, and provides a vehicle body welding assembly that allows the replacement of old and new positioning units in a short period of time, and also enables a significant reduction in the cost required for this replacement. The purpose is to provide a line.

(Structure of the Invention) In order to achieve the above-mentioned object, the present invention includes: a transport device for transporting a vehicle body in a suspended state; and a rail laid below the transport device along the vehicle body transport direction. , a bogie disposed on the rail, a fixing device that fixes the bogie at a set position so that it cannot run, and a positioning unit that is installed on the bogie and positions the vehicle body prior to welding the vehicle body. It is configured as a car body welding assembly line, which is characterized by the following:

With the above configuration, since the car body is transported in a suspended state, it is possible to avoid the trolley from interfering with the transport of the car body during welding assembly, but when replacing the positioning unit, it is possible to avoid the trolley from interfering with the transport of the car body using the fixing device. All you have to do is release the fixing and remove the bogie with the old positioning unit installed on the rail, then run the bogie with the new positioning unit installed on the rail and re-fix it in the specified position. That will happen.

(Example) In Fig. 1, A is the car body to be welded,
As is well known, these are roughly divided into floor panels and cab side panels, which are suspended from hangers 2 that run along hanger rails 1 as shown in FIG. In Figure 2, it is conveyed from right to left.

Below the hanger rail 1, two rails 3 are laid on the floor F along this, and along the rails 3, a plurality of welding stations S ₁ to S ₆ are configured in series with each other. . Each of these welding stations S ₁ to _{S 6} is composed of a truck 4 and a positioning unit, which will be described later, installed on the truck 4 (the positioning unit is omitted in FIGS. 1 and 2). be). _Of course, at each welding station S ₁ , S ₂ . In addition, the welding station
At S ₁ and S ₅ , the cab side panel is positioned relative to the floor panel, and welding is performed on the car body A, and the other welding stations S ₂ ,
In S ₃ , S ₄ , and S ₆ , only the floor panel is positioned and the predetermined positions of the vehicle body A are welded. In addition, two of the welding robots 5 are located between welding stations _S3 and _S4 , and two are located between welding stations S3 and _S4 .
The two welding robots 5 located at S ₆ are designed to work on the car body A located at both welding stations S ₃ and S ₄ or S ₅ and S ₆ , and the other welding robots 5 are Each welding station S ₁ to _{S 6} is dedicated.

The above-mentioned cart 4 is moved by the jack 6 as a fixing device at a position corresponding to the positioning unit B installed thereon, that is, if it is a cart on which the positioning unit B for the welding station S ₁ is installed, the welding station S ₁ is moved by the jack 6 as a fixing device. It is fixed so that it cannot run. That is, each bogie 4 has its running wheels 7 (shown only at the welding station S ₁ in FIG. 1) lifted off the rail 3 by the jacks 6 at the above-mentioned predetermined positions, as also shown in FIG. This jack 6 is shown in FIG. 1 only at the welding station _S5 .

Next, the positioning unit B installed on the trolley 4 will be explained based on FIGS. 3 and 4, but since the positioning unit B itself can basically be applied as a conventional one,
Only the welding station _S5 equipped with the above-mentioned panel attachment jig will be described as a representative.

First, in Fig. 3, there is a lifting platform 1 on the trolley 4.
0 is installed to be able to move up and down, and the elevating table 10 is raised and lowered by an elevating cylinder 11. A pair of jig holding shafts 13, each extending in the direction in which the rails 3 are laid, are rotatably held on the lifting platform 10 by brackets 12.
This jig holding shaft 13 has jig mounting bodies 14 and 15.
are integrally attached, and the jig attachment body 14 has positioning pins 16 and 17, and the jig attachment body 1
5 is equipped with clamp arms 18 and 19. The positioning pins 16, 17 or the clamp arms 18, 19 are attached to opposite sides of the jig holding shaft 13 at 180 degrees in the radial direction, and the positioning pins 16 and clamp arms 18 on one side are
For example, the vehicle body A is of a hatchback type, and the positioning pin 17 and the clamp arm 1 on the other side are
9 is applied to slightly different types of car bodies A, for example, when the car body A is a sedan type, and the switching is performed by changing the jig holding shaft 13 depending on the type of the car body A. This is done by rotating the sensor 180 degrees in forward and reverse directions using a motor (not shown). Note that FIG. 3 shows a case in which positioning pins 16 and 17 are provided on the jig holding shaft 13 on the right side, and clamp arms 18 and 19 are provided on the jig holding shaft 13 on the left side. Both of the left and right jig holding shafts 13 are provided with positioning pins 16, 17 and clamp arms 18, 1 at intervals in the axial direction.
9, and the positioning pin 1
6, 17, or the clamp arms 18 and 19 are installed slightly shifted in the axial direction of the jig holding shaft 13.

Locating pin 16 or 17 as described above
is inserted into a positioning hole formed at a predetermined position of the vehicle body A to position the vehicle body A when the elevator platform 10 is raised. Further, when the elevator platform is raised, the clamp arm 18 or 19 is actuated by an air cylinder or the like (not shown) to grip a predetermined position of the vehicle body A.
It is positioned as described above and functions to fix the vehicle body A without rattling. Of course, the lifting platform 10 supports the vehicle body A when it is lifted.
Welding is performed by the welding robot 5 at the elevated position of the lifting platform 10.

Next, to explain the structure of the part for positioning the cab side panel, a guide base 20 is fixed on the trolley 4 on the side of the elevator platform 10, and a moving block 21 is fixed to the guide base 20.
However, it is designed to be reciprocated in a direction perpendicular to the rail 3 by a motor (not shown). The moving block 21 is rotatably provided with a holding shaft 22 extending parallel to the jig holding shaft 13, and a plurality of holding cylinders 23 are integrated with the holding shaft 22. For each holding cylinder 23,
A pole 25 having a jig 24 for positioning and clamping is rotatably attached. Note that the holding shaft 22 is rotationally driven by a motor 26,
Further, the pole 25 is rotationally driven by a motor 27.

Such a panel (positioning device) prevents interference with the hanger 2 during vehicle body delivery when the pole 25 is tilted about the holding shaft 22, and prevents the pole 25 from interfering with the hanger 2 during vehicle body delivery.
When standing up, it is transferred and held at a predetermined position on the vehicle body A,
Welding can be performed by a welding robot 5.

Note that the carts 4 disposed at the welding stations S ₂ , S ₃ , S ₄ , and S ₆ are only provided with a lifting platform 10 for positioning the floor panel, and the structure is the same as that described above. is omitted.

Next, a case will be described in which the vehicle body A is changed to a completely different one due to a model change and the positioning unit B is replaced accordingly.

First, the support of the truck 4 by the jack 6 is released, and the truck 4 is lowered to a position where the truck 4 can run on the rails 3. Next, the carts 4 in each of the welding stations S ₁ to _{S 6} are run on the rails 3 and carried out from one end of the welding assembly line, and these carts 4 are removed together with the old positioning unit B.

Next, the carts 4 on which the positioning unit B corresponding to the car body A after the model change is installed are carried in from the other end of the welding assembly line, for example, and run on the rails 3. It is fixed in a predetermined position so that it cannot run. This results in
Installation of the new positioning unit B is completed.

Here, the new positioning unit B is preferably installed separately on the trolley 4 during production (during welding) using the old positioning unit B. In this case, after removing the old positioning unit B, the new positioning unit It is only necessary to position the cart 4 on which the unit B is installed, and the work for replacing the positioning unit B is greatly shortened. Furthermore, if there are parts of the old positioning unit B that can be used in the new positioning unit B, they can be applied to the new positioning unit B. It should be noted that the welding robot 5 is generally of a teaching type (playback type) and has versatility, so it may be continued to be used as is.

Although the embodiments have been described above, the present invention is not limited thereto, and includes, for example, the following cases.

As a fixing device for the truck 4, instead of using the jacks 6, for example, a brake provided on the truck 4 may be used. In this case, trolley 4
For example, in order to securely fix the rail 3
The wheel 7 of the truck 4 may be formed into a pinion shape which meshes with the rack.

The positioning unit B installed on the trolley 4 is not limited to the one in the embodiment, and any suitable type can be adopted.

(Effects of the Invention) As is clear from the above, the present invention has the following advantages:
During welding assembly, welding and assembly can be carried out properly because the trolley does not interfere with transporting the vehicle body. On the other hand, when replacing the positioning unit, there is no need to level the floor, and the old and new positioning units can be replaced by the trolley. Since it can be removed or installed in a predetermined position extremely easily by running on rails, the period for replacement can be significantly shortened and the cost of replacement can be significantly reduced.

Note that preparing a new positioning unit and a completely new trolley for this new positioning unit requires at least the additional cost of the trolley, but this cost is small compared to the cost of land leveling work, etc. Therefore, it is possible to significantly reduce costs overall.

[Brief explanation of the drawing]

FIG. 1 is an overall simplified plan view showing one embodiment of the present invention. FIG. 2 is a partial side view of FIG. 1. FIG. 3 is a front view showing an example of the positioning unit B installed on the trolley. Figure 4 is a right side view of Figure 3. A: Vehicle body, B: Positioning unit, 3: Rail, 4: Dolly, 6: Jacket.

Claims (1)

[Scope of Claims] 1. A transport device for transporting a vehicle body in a suspended state; a rail laid below the transport device along the vehicle body transport direction; a trolley disposed on the rail; A car body welding assembly line comprising: a fixing device that fixes a bogie in a predetermined position so that it cannot run; and a positioning unit that is installed on the bogie and positions the car body prior to welding the car body.