JPH0438950Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an improvement of a spot welding device that performs spot welding by a robot, and is particularly suitable for spot welding an automobile seat frame composed of frame lines. Related to spot welding equipment.

[Conventional technology]

Conventionally, when spot welding a car seat frame using a welding robot using a frame line with a diameter of 4 mm to 6 mm, for example, the direction and range of movement of the robot supporting the spot gun is often limited, and it is difficult to spot weld outside of these ranges. If there is a welding spot location, it is difficult for the robot to spot the spot.

That is, when spot welding the frame lines 1 and 2 at point 3 as shown in FIG. 2, the fixed electrode 4 on which the frame lines 1 and 2 are placed is in a nearly horizontal state in the jig as shown in FIG. If a spot gun supported by a robot (not shown) can apply pressure only within the range of angle α when the spot gun is fixedly installed on A) Pressurization becomes impossible.

For this reason, conventionally, as shown in FIG. 4, the jig 5 is rotated so that the dot angle β falls within the range of the angle α, or additional dots are made in a separate process. Note that this type of device was first developed in 1983.
There are proposals disclosed in Japanese Patent Application Laid-open No. 23242 and Japanese Patent Application Laid-Open No. 125281/1983.

[Problems to be solved by the invention] However, as mentioned above, in order to rotate the jig 5 by the required angle, a rotation mechanism for the jig 5 is required, which makes the structure complicated and it cannot be rotated from any direction. There was a problem in that it was difficult to generalize the system so that it could hit points.

Moreover, there was also the problem that the cycle time became longer due to the time required for rotation. In addition, there was a problem in that equipment costs and man-hours would both increase in order to increase the number of strokes in a separate process.

In addition, the proposals disclosed in the above two publications are both related to means for converting the welding point position with respect to the workpiece, and do not take into account spot welding of workpieces in positions outside the possible direction and range of the welding point by the robot. Nakatsuta.

The present invention has been developed in view of the above circumstances, and has a simple structure that allows for general-purpose equipment, and allows the robot to place dots on uniquely shaped frame line members even at dot positions outside the robot's movable range. The purpose of the present invention is to provide a spot welding device that has the following features.

[Means for solving problems]

In order to achieve the above object, the present invention involves sandwiching a pair of frame wire members placed on a jig between a fixed electrode and a movable electrode through electrode chips, and applying pressure and electricity using a robot. In a spot welding device for frame line members that performs spot welding in a crisscross pattern, the jig is equipped with a spot gun having an inclined swinging arm rotatably attached to one end, and an inclined fixed electrode placed outside the movable range of the robot. A movable electrode is disposed with an axis inclined, and a movable electrode is provided at one end of the swinging arm, and the movable electrode chip is attached at an angle so as to be able to face the tip of the fixed electrode that is tilted. The end and the opposite side of the spot gun to which the swing arm is attached are rotatably connected via a cylinder device, and the welding current is applied to the fixed electrode and the movable electrode by the robot. A pair of contact electrodes connected to the fixed electrode and the movable electrode by cables, respectively, are provided within the movable range of the robot away from the spot gun and the fixed electrode.

[Effect]

According to the above configuration, the movable electrode is rotatably attached to one end of the spot gun fixed to the lower surface of the jig, and when the movable electrode is rotated by the actuator attached to the other end of the spot gun, the movable electrode is rotated by the actuator attached to the other end of the spot gun. A welding member is clamped under pressure by a fixed electrode fixed to the jig and the movable electrode.
In this state, the pair of contact electrodes is pressurized and energized by the robot, so that a current flows between the fixed electrode and the movable electrode connected to each of these contact electrodes, and the parts to be welded are spot welded. .

Therefore, even if the spot welding point of the welded member is outside the movable range of the robot, the spot welding can be done without changing the posture of the jig.

〔Example〕

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a spot welding machine according to the present invention will be described below with reference to the drawings.

FIG. 1 shows an embodiment of the present invention. In the figure, parts that are the same as or equivalent to those of the conventional example shown in FIG. 3 are designated by the same reference numerals.

A fixed electrode 4 is fixedly installed on a jig surface plate 5,
Frame lines 1 and 2, which are members to be welded, as shown in FIG. 3, are mounted on an electrode chip 6 provided on the fixed electrode 4 so as to intersect with each other.

A spot gun 7 is fixedly installed on the lower surface of the jig surface plate 5, and a swing arm 8 is located near the portion of the spot gun 7 where the fixed electrode 4 is provided.
is rotatably mounted via a shaft 9.

A movable electrode 10 is attached to the upper end of the swing arm 8, and an electrode tip 11 is provided at the tip so as to be able to face the electrode tip 6 on the fixed electrode 4 side. Further, a shaft 12 is attached to one end of the spot gun 7 on the opposite side to which the swing arm 8 is attached.
One end of the air cylinder 13 is rotatably attached to the rod 13a of the air cylinder 13, and the rod 13a of the air cylinder 13 has a shaft 14 attached to one end of the swing arm 8 on the side opposite to the side on which the movable electrode 10 is attached. are rotatably connected through the

On the other hand, on the jig surface plate 5 within the movable range of the robot (not shown), a pair of contact electrodes 15,
16 are fixedly installed, each with 1 robot gun.
7 and 18 to apply pressure and current. These contact electrodes 15 and 16 are connected to the fixed electrode and movable electrode 10 by cables 19 and 20, respectively.

Next, the operation of this embodiment will be explained. When the air cylinder 13 is actuated, its rod 13a protrudes and rotates the swinging arm 8 about the shaft 9 in the counterclockwise direction in the figure. As a result, the frame lines 1 and 2 are held between the electrode chips 6 and 11 under pressure.

In this state, when contact electrodes 15 and 16 are pressurized and energized by robot guns 17 and 18, respectively, current from the positive electrode of a welding power source (not shown) is applied to contact electrode 16, cable 20, movable electrode 10, frame lines 2 and 1, It flows through the fixed electrode 4, cable 19, and contact electrode 15 to the negative electrode of the welding power source, and spot welding is performed between the frame lines 2 and 1.

After welding is completed, the operation of the air cylinder 13 is stopped, and when the rod 13a is retracted into the air cylinder 13, the swinging arm 8 rotates clockwise in the figure, and the electrode tips 6, 11 indicated by the frame lines 1 and 2 The pressure clamping by the spot welding frame lines 1 and 2 is released, and the spot welded frame lines 1 and 2 can be taken out from the welding position by a robot.

According to this embodiment, the frame line 1, which is the member to be welded,
Since the jig that clamps and presses 2 and the means for energizing the frame lines 1 and 2 are separated, by providing the contact electrodes 15 and 16, which are the energizing means, within the movable range of the robot, the dot position can be adjusted. Even outside the movable range of the robot, spot welding can be performed by applying pressure and current using a pressure jig.

Therefore, it is no longer necessary to change the attitude of the jig surface plate 5 or perform additional strokes in a separate process as in the past. As a result, all the spot welding points at the necessary positions of the frame lines 1 and 2 can be made in one process by simple improvement of the equipment.

Furthermore, by separating the jig that pressurizes the frame wire from the current supply means, the jig can be easily changed, and it has become easier to spot weld a wide variety of products.

In the above-mentioned embodiment, the case where the frame lines 1 and 2 constituting the seat frame of an automobile are spot welded is explained, but it goes without saying that it can also be applied to the case of spot welding other welded parts and has the same effect. Nor.

[Effect of idea]

As described above, according to the present invention, the tilted swing arm and the tilted fixed electrode are arranged with their axes tilted outside the movable range of the robot, and the contact for supplying welding current to the fixed electrode and the movable electrode is arranged. Since the electrode is separated from the spot gun and placed within the robot's movable range, it can be used at hitting points outside the robot's movable range without changing the posture of the jig.
In addition, the direction and range of movement of the robot supporting the spot gun is not limited, making spot welding easy. It has an effect that you don't need to practice. Therefore, even if the item has a unique shape such as a frame line, all spot welding points at the necessary positions can be welded in one place.
It can be easily performed in the process, efficient welding can be performed with simple equipment, and the effects of making equipment more versatile are significant.

[Brief explanation of the drawing]

Fig. 1 is a front view showing an embodiment of the spot welding device according to the present invention, Fig. 2 is a perspective view showing the workpiece to be welded in Fig. 1, and Figs. 3 and 4 respectively show conventional spot welding operations. FIG. 1, 2... Frame line (member to be welded), 4... Fixed electrode, 5... Jig, 6, 11... Electrode chip, 7...
... Spot gun, 8 ... Swinging arm, 10 ... Movable electrode, 13 ... Air cylinder, 15, 16 ...
contact electrode.

Claims (1)

[Scope of utility model registration request] A frame line member in which a pair of frame line members placed on a jig are sandwiched between a fixed electrode and a movable electrode via an electrode chip, and spot welded in a cross shape by applying pressure and electricity using a robot. In the spot welding device described above, a spot gun having an inclined swinging arm rotatably attached to one end of the jig and an inclined fixed electrode are arranged with the axis line inclined outside the movable range of the robot, A movable electrode is provided at one end of the swinging arm, and the movable electrode tip is attached at an angle so as to be able to face the tip of the tilted fixed electrode, and the other end of the swinging arm is connected to the swinging arm of the spot gun. The fixed electrode and the movable electrode are rotatably connected to the opposite side through a cylinder device, and the fixed electrode and the movable electrode are connected to each other so that the welding current is applied to the fixed electrode and the movable electrode by the robot. A spot welding device characterized in that a pair of contact electrodes connected by a cable are provided within a movable range of a robot apart from the spot gun and the fixed electrode.