JPH0421661Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a welding device equipped with a welding robot for assembling the body of an automobile.

(Prior Art) Conventionally, various structures of this type of welding apparatus are known. For example, in order to weld the cab sides on the left and right sides of the underbody, there are some that are equipped with a cab side setter jig and a welding robot. In this welding device, the cabside setter jig approaches the underbody on the conveyance line from the left and right, and after assembling the cabside received from a separate device into predetermined positions on the right and left of the underbody, the jig approaches the underbody on the conveyance line. Welding robots suspended on both the left and right sides of the upper part are moved forward by forward and backward movement means consisting of motors, etc., and weld the cab side to the underbody. Furthermore, Japanese Patent Publication No. 57-30591 discloses a method for welding a rear end panel to the rear part of the underbody. In this welding device, a welding gun is rotatably supported to the fuselage near its electrode position, and the welding gun is vertically moved intermittently in the width direction at the rear fender opening. Welding is performed, and the rear fender's pocket is tilted by rotation, and moved in an inclined state to weld to the depths of the pocket.

(Problems to be Solved by the Invention) However, in any of the above conventional welding devices, there is a mechanism to prevent interference between the welding robot and the underbody on the conveyance line when the means for moving the welding robot forward and backward breaks down. It is necessary to evacuate the welding robot, but there is a problem in that evacuating is extremely troublesome. In addition, in the former type of welding equipment that welds the cab side, when welding is completed, the cab side setter jig is retracted and then the welding robot is retracted, so the underbody that has finished welding is transported to the next welding process. There was a problem that I had to make the time longer.

The present invention was made with the purpose of solving the above-mentioned problems of the former welding device for welding the cab side, and the retracting movement of the welding robot is performed by a means separate from the forward movement of the welding robot. Moreover, it is designed to be carried out in synchronization with the cab side setter jig.

(Means for Solving the Problems) In order to solve the above problems, the solution means of the present invention is provided on both sides of the conveyance line of the underbody of an automobile so as to be movable forward and backward with respect to the conveyance line,
A pair of left and right cab side setter jigs for assembling cab sides on the left and right sides of the underbody, and a pair of cab side setter jigs located corresponding to one end side of the underbody in the conveying direction and connected to the conveying line. The robot is provided with a pair of left and right welding robots that are movable forward and backward relative to the underbody and weld the cab sides to the left and right sides of the underbody. Then, each of the cab side setter jigs is moved forward and backward between an assembly position where the cab sides are assembled to the left and right sides of the underbody and a retracted position where the cab sides are evacuated from the conveyance line and receive new cab sides. Prior to the forward movement of the cab side setter jig to the assembly position by the means and the jig moving means, the welding robot on the corresponding side is moved from the retracted position where it has been retracted from the conveyance line to the underbody of the cab side. A robot forward movement means for moving the welding robot forward to a welding position for welding to the underbody, and a robot backward movement cylinder for moving the welding robot backward from the welding position to a retracted position after welding the cab side to the underbody. Furthermore, a control valve that adjusts supply and discharge of fluid to the robot retraction cylinder, a jig position detection means that detects the position of the cab side setter jig, and a robot position detector that detects the position of the welding robot. The apparatus includes a detection means, and a control means for receiving the outputs of the two position detection means and controlling the control valve so as to cause the welding robot to move backward in synchronization with the cab side setter jig.

(Function) Accordingly, in the present invention, when the underbody of an automobile is carried between the left and right cab side setter jigs and stopped on the conveyance line, one of the left and right welding robots, for example, the left side, moves forward. The cab side setter jig 3 is moved forward from the retracted position to the welding position by the moving means.
While holding the left cab side of the received automobile, the cab side is moved forward from the retracted position to the assembly position by the jig moving means, and the cab side is assembled to the left side of the underbody. After that, a welding robot welds the left cab side to the underbody. When welding is finished, the cab side setter jig and the welding robot are synchronously moved backward to the original retracted position by the jig moving means and robot retracting cylinder under the control of the control means, and the other (right side) ) wait for the cab side setter jig and welding robot to weld the cab side to the right side of the underbody. The welding on the right side is performed in the same way as the welding on the left side.

(Example) Hereinafter, an example of the present invention will be described based on FIGS. 1 to 3.

As shown in FIGS. 1 and 2, the welding apparatus 1 of this embodiment includes a pair of cab side setter jigs 3 disposed on both left and right sides of a conveyance line 2, and each cab side setter jig 3. Equipped with a pair of jig moving means 4 for the jig 3, a pair of welding robots 5 disposed on both left and right sides above the conveyance line 2, and a pair of drive means 6 for each welding robot 5. It will be done. In the transport line 2, a large number of underbodies 35 of automobiles are placed on the upper part, and a transporting device 2a moves intermittently in the direction of the arrow in FIG. 1 to transport the underbodies 35 into and out of the welding installation 1 _. It is provided. Each cab side setter jig 3 is
A support stand 8 is provided on the upper surface of the base 7 so as to be movable from the left and right with respect to the conveyance line 2, and a support shaft 9 is provided on the support stand 8 in parallel to the conveyance line 2.
A jig main body 10 is rotatably supported on the outer peripheral surface of the support shaft 9. Each jig moving means 4 is composed of a hydraulic cylinder 11 and is also provided with a jig position detecting means 12. The hydraulic cylinder 11 has a central portion supported swingably on the upper surface of the base 7 and is connected to the support base 8 via a piston rod 13 . Jig position detection means 1
Reference numeral 2 includes an encoder for detecting the position of the cab side setter jig 3 in the left-right direction from time to time, and is mounted on a support base 8. Each welding robot 5 includes a welding gun 15 supported by a support portion 14. The support part 14 is a cab side setter jig 3.
The jig moving means 4 (hydraulic cylinder 11) is suspended from a ceiling beam 16 disposed above one end in the left-right direction with respect to the conveyor line 2, and is moved by the jig moving means 4 (hydraulic cylinder 11) by a robot advancing means (motor) not shown. It is provided so that it can be moved forward to the assembly position prior to the forward movement of the cab side setter jig 3. The welding gun 15 performs movements such as swinging and rotation by hydraulic pressure supplied via a hydraulic cable 17, and the electrode 18 of the welding gun 15 is connected to a power supply means 19.
The welding current is supplied via. Each power supply means 19
is the rail 2 laid in the left and right direction on the ceiling beam 16.
A movable body 21 is slidably provided on the movable body 2
1, one end of a support arm 22 is swingably supported, and the other end of the support arm 22 is suspended from a ceiling 24 via a hanging device 23, and is welded to a transformer 25 fixed to a ceiling beam 16. An intermediate portion of a power supply cable 26 disposed between the gun 15 and the gun 15 is fixed to the other end of the support arm 22. Each drive means 6
The robot retraction hydraulic cylinder 27, the robot position detection means 28, and the control means 2 shown in FIG.
It consists of 9. The hydraulic cylinder 27 is swingably supported at its center by the lower surface of the ceiling beam 16, and is connected to the support portion 14 of the welding robot 5 via a piston rod 30. The robot position detection means 27 consists of an encoder for momentarily detecting the position of the welding robot 5 in the left and right direction, and is mounted on the support section 14. Each control means 29 includes a comparator connected between both position detection means 12 and 28 and the hydraulic cylinder 27, a servo amplifier, and a servo bubble 33 as a control valve, and controls the backward movement of the welding robot 5. The servo valve 33 is controlled to synchronize with the corresponding backward movement of the cab side setter jig 3. The servo valve 33 includes a hydraulic pump 34 that supplies hydraulic pressure to the hydraulic cylinder 27.
is connected.

Next, the operation of the welding device 1 will be explained. First, on the conveyance line 2, the underbody 35 of the automobile is carried between the left and right cab side setter jigs 3 and stopped. Next, either the left or right welding robot 5 (the left side in FIG. 1) is moved to the welding position by the robot forward movement means, and
Next, the jig body 10 of the cab side setter jig 3
However, with the left cab side 36 of the automobile received from a separate device (not shown) provided above, the hydraulic cylinder 1 is rotated vertically.
1, it is moved to the right, and the cab side 36 is positioned on the left side of the underbody 35 and stopped. Then, the welding robot 5 welds the left cab side 36 to the underbody 35. When welding is finished, the cab side setter jig 3 and the welding robot 5 move backward to the original retracted position in synchronization, and the other (right side) cab side setter jig 3
The welding robot 5 waits for welding the cab side 36 to the right side of the underbody 35. The welding on the right side is performed in the same way as the welding on the left side.

To explain the above-mentioned synchronous evacuation, both position detection means 12 and 28 momentarily detect the current positions of the corresponding cab side setter jig 3 and welding robot 5, and input their output signals to the comparator 31. do. The comparator 31 that receives both signals is
The deviation amount of the relative position between the cab side setter jig 3 and the welding robot 5 from the set value is calculated, and the output signal is amplified by the servo amplifier 32 and inputted to the servo valve 33. The servo valve 33 synchronizes the operation of the hydraulic cylinder 27 with the hydraulic cylinder 11 by supplying and cutting off the hydraulic pressure from the hydraulic pump 34 to the hydraulic cylinder 27 so that the deviation amount is always zero. It is.

When the scheduled welding is completed, the welded underbody 35 is carried out by the transport line 2, and the next underbody 35 is carried in.

As described above, since each welding robot 5 retreats in synchronization with the corresponding cab side setter jig 3, the time required for this retreat is shortened, and the conveyance tact in the conveyance line 2 can be shortened. . Further, the power supply means 19 is connected to the welding robot 5.
When the welding robot 5 moves, the movement of the power supply cable 26 is suppressed, and various interference areas existing near the movement range of the welding robot 5, such as the interference area with the cab side setter jig 3 that moves synchronously, and the This prevents the power supply cable 26 from entering into an interference area with the cab side 36 that descends to be supplied to the jig 3. Both hydraulic cylinders 11 and 27 may be air cylinders, and it is preferable to apply a throttle to these cylinders, since this has the effect of preventing sudden operation.

In addition, the drive means 6 can forcibly evacuate the welding robot 5 from the conveyance line 2 to prevent the line from stopping if the conventional robot advance movement means such as a motor breaks down.

(Effects of the Invention) As described above, in the present invention, the welding robot can retreat from the conveyance line in synchronization with the cab side setter jig, so that the conveyance tact can be shortened. Further, even if the forward movement means of the welding robot fails, the welding robot can be forcibly evacuated from the conveyance line.

[Brief explanation of the drawing]

FIG. 1 is a plan view of a welding device showing an embodiment of the present invention, FIG. 2 is a view taken along arrow A in FIG. 1, and FIG. 3 is a system diagram of a driving means of a welding robot. 1... Welding device, 2... Transfer line, 3... Cab side setter jig, 4... Jig moving means,
5... Welding robot, 6... Drive means, 11...
Hydraulic cylinder, 12... Jig position detection means, 27
... Hydraulic cylinder, 28 ... Robot position detection means, 29 ... Control means, 33 ... Servo valve,
35...Underbody, 36...Cabin side.

Claims (1)

[Scope of Claim for Utility Model Registration] A pair of left and right cab side setters that are provided on both sides of a conveyance line of an automobile underbody so as to be able to move forward and backward with respect to the conveyance line, and for assembling cab sides on the left and right sides of the underbody. and a jig, which is located corresponding to one end of each cab side setter jig in the conveyance direction of the underbody and is movable forward and backward with respect to the conveyance line, and welds the cabside to the left and right sides of the underbody. a pair of left and right welding robots, and each of the above-mentioned cab side setter jigs, between an assembly position where the above-mentioned cab sides are assembled to the left and right sides of the underbody and an evacuation position where they are evacuated from the above-mentioned conveyance line and receive new cab sides. A jig moving means for moving the cab side setter jig forward and backward by the jig moving means, and the welding robot on the corresponding side is evacuated from the conveyance line before the jig moving means moves the cab side setter jig forward to the assembly position. A robot forward movement means for moving the robot forward from a retracted position to a welding position for welding the cab side to the underbody; and a robot for retracting the welding robot from the welding position to the retract position after welding the cab side to the underbody. a retracting cylinder; a control valve for adjusting supply and discharge of fluid to the robot's retracting cylinder; a jig position detection means for detecting the position of the cab side setter jig; and a jig position detecting means for detecting the position of the welding robot. and control means for receiving the outputs of both the position detecting means and controlling the control valve to cause the welding robot to move backward in synchronization with the cab side setter jig. Characteristic welding equipment.