JPS6250224B2 - - Google Patents

Description

[Detailed description of the invention] This invention relates to improvements in spot welding machines.

A conventional stationary spot welding machine is designed to feed a workpiece to be welded when performing a welding operation. For this reason, spot welding machines had the following drawbacks.

The equipment space for the welding machine was required to be more than twice the length of the workpiece.

The gun-driven workpiece feed mechanism was attached to the outside of the workpiece and became larger in size to increase feed accuracy.

Unspecified pitch feeding using a tracing device was not possible.

It was not possible to change the hitting point position.

The movement trajectory of the gun tip was flat.

In view of the above, this invention allows the spot welding machine itself to be made smaller by fixing the workpiece and moving the gun, thereby reducing the equipment space, and also allows for unspecified pitch feeding and switching of welding points using a tracing device. The object of the present invention is to provide a gun self-propelled spot welding machine which is capable of welding even three-dimensional workpieces.

Next, the present invention will be explained based on embodiments shown in the drawings.

1 and 2 show an indexing section of a spot welding machine, with FIG. 1 being a front view and FIG. 2 being a side view. In the figure, the frame 1 is formed by welding strip-shaped plates in the longitudinal direction, and its cross section is approximately square. On the upper surface of the frame 1, there is a strip-shaped guide that is thicker than the plate thickness of the frame 1. Rail 2 is welded. Guide rails 2 are provided on the front and bottom surfaces of the frame 1.
A front plate 3 and a bottom plate 4, which have substantially the same shape, are each welded to each other. The rail member 5 consisting of the frame 1, guide rail 2, substrate 3 and bottom plate 4 is attached to a spot welding machine (not shown) via support members 6, 6' attached to both ends thereof.
The traveling bogie 7 has a latch mounting plate 8 located above the front plate 3 of the rail member 5, and a support plate 9 disposed below the bottom plate 4 in parallel with the bottom plate 4. are connected by a connecting plate 10. The connecting plate 10 is made up of a horizontal plate 10a above the guide rail 2 that is parallel to the guide rail 2, and a vertical plate 10b that is bent downward at a substantially right angle to the horizontal plate 10a at the rear of the frame 1. There is. Horizontal board 1
Below 0a, there is a guide mounting member 11 whose front part is attached to the latch mounting plate 8, and an appropriate number of rollers 12 and rollers 12' are mounted on the front and rear parts of the guide mounting member 11. These rollers 12 and 12' allow the carriage 7 to move on the guide rail 2 of the rail member 5 in its longitudinal direction. The rail member 5 is provided with an upper regulating member 13 and an upper regulating member 13 at the upper part of the guide rail 2 and the lower part of the bottom plate 4 in order to regulate the movement of the traveling carriage 7 in the front and back direction (leftward and rightward in FIG. 2) with respect to the rail member 5. A lower regulating member 14 is attached, the upper regulating member 13 engages with an upper roller 15 pivotally mounted on the upper and lower surface of the guide mounting member 11, and the lower regulating member 14 is pivotally mounted on the support plate 9. Lower roller 16 protruding from the upper surface of support plate 9
is engaged with. An angled gun mounting member 17 is attached to the lower surface of the support plate 9, and a bracket 18 is provided on the rear surface of the vertical plate 17a of the gun mounting member 17, and a gun cylinder 19 is attached to the top of the bracket 18. It is being

As described above, the axis of the gun cylinder 19 attached to the lower part of the traveling carriage 7 is perpendicular to the guide rail 2 of the rail member 5. At the bottom of the gun cylinder 19, there is a cylinder rod 20 that is moved up and down by air pressure acting on the gun cylinder 19.
An upper electrode 21 is attached to the lower end of.

The hook 22 has a vertical groove 24 in the upper hook part 23.
The lower part of the hook part 23 is a round bar-shaped link rod 25. This link rod 25 has its lower end attached to a rod base 26 fixed to the cylinder rod 20, and the upper end of the link rod 25 is attached to two supports 2 attached to the gun cylinder 19.
7, 27 so as to be slidable. In this way, the hook 22 attached to the gun cylinder 19 can move up and down while remaining parallel to the cylinder rod 20 when the cylinder rod 20 moves up and down.

The index feed link 28 (hereinafter referred to as the feed link) is swingably attached to the gun mounting member 17 by a support shaft 29 attached to the lower part of the vertical plate 17a of the gun mounting member 17. The feed link 28 includes a shoot arm 28a having a roller-shaped cam follower 30 attached to its tip that engages with the vertical groove 24 of the hook 22, and a feed pawl 31 to be described later.
There is a long arm 28b whose central portion is pivotally connected 61. In this embodiment, the long arm 28
The length b is more than twice the length of the shot arm 28a, and the angle between the two is approximately 90°. A roller-shaped cam follower 32 is pivotally attached to one end of the feed claw 31, and the other end forms a claw portion 31a. The feed claw guide cam 33 is attached to the vertical plate 17a of the gun mounting member 17 below the feed claw 31, and the surface on the feed claw 31 side becomes a cam surface 33a. The cam follower 32 of the feed pawl 31 is activated by the cam surface 33a of the feed pawl guide cam 33 by a tension spring 34 attached between the base of the long link 28b of the feed link 28 and the vicinity of the cam follower 32 of the feed pawl 31. is pressed against. A feed pawl stopper 35 that comes into contact with the tip of the pawl portion 31a of the feed pawl 31 to stop the movement of the feed pawl 31 to the right (in FIG. 1) is located at the lower part of the front plate 3 of the rail member 5, and It is attached to the right end. This feed pawl stopper 35 is provided with a first stopper surface 35a extending downward at the right end, and the left end surface is a second stopper surface 35b, and the first stopper surface 35a and the second stopper surface 35b are connected to each other. In between, there is a downwardly inclined slope 3
There is a 5c. A feed pawl stopper 35' having a stopper surface 35'b is provided on the front plate 3 of the rail member 5 at a desired distance from the feed pawl stopper 35. A feed pawl stopper 35'' having a stopper surface 35''b is provided at a distance.

The hitting point positioning latch 36 (hereinafter referred to as latch) has a boss portion 36a pivotally attached to the latch mounting plate 8 of the traveling truck 7 via a support shaft 39. The latch 36 has a lower claw 37 and an upper claw 38 attached to the boss portion 36a.
A lower claw 37 located on the right side in FIG. 1 and an upper claw 3 located on the left side in FIG.
The number 8 is shaped like a letter V. The latch 36 has a tension spring 42 attached to a pin 40 protruding from the end of the upper claw 38 and a pin 41 implanted in the latch mounting plate 8, so that a clockwise rotational force is constantly applied to the latch 36. There is. The hitting point positioning stopper 43 is attached to the upper part of the front plate 3 of the rail member 5. The dot positioning stopper 43 has a first dot positioning stopper surface 43a vertically provided at its right end to stop the rightward movement of the lower claw 37 of the latch 36. This hitting point positioning stopper 43 has an inclined surface 43b which becomes higher in order from the bottom to the left side of the stopper surface 43a, and furthermore, at the end of the inclined surface 43b, there is a second stopper for positioning a second hitting point parallel to the stopper surface 43a. There is a surface 43c. On the left side of the hitting point positioning stopper 43, there is a third stopper surface 4.
3'c and an inclined surface 43'b, and on the left side of the third hitting point positioning stopper 43', a fourth hitting point position stopper 43'' having a fourth stop surface 43''c is provided. They are attached to the front plate 3 of the rail member 5 at desired intervals. The original position stopper 44 is the point position stopper 4.
3 is attached to the front plate 3 of the rail member 5, and comes into contact with the lower surface of the upper pawl 38 of the latch 36 to determine the original position (starting position) of the traveling carriage 7. This original position stopper 44 is
The position can be moved in the direction of movement of
By moving the original position stopper 44, the original position of the traveling carriage 7 is changed.

A stopper attachment member 46 for attaching an automatic return stopper 45 is provided at the left end of the upper regulating member 13 attached to the upper surface of the guide rail 2 of the rail member 5. This stopper mounting member 46 is fitted onto the outside of the upper regulating member 13 and includes a sliding portion 46a that is slidable relative to the upper regulating member 13, and a vertical member 46b provided at the right end of the sliding portion 46a. It is made up of The vertical member 46b extends from the top to the bottom on the front surface of the front plate 3 of the rail member 5, and an automatic return stopper 45 is attached at a position facing the original position stopper 44. The automatic return stopper 45 is movable relative to the vertical member 46b, and its moving direction is the same as the moving direction of the original position stopper 44. The stopper mounting member 46 is a vertical member 46b.
An outwardly threaded screw member 47 is attached to the lower end of the slider 46 parallel to and in the same direction as the slider 46. This screw member 47 has a threaded pipe 48 whose movement in the axial direction is regulated at the left end of the rail member 5 and is rotatably supported.
The position of the automatic return stopper 45 is changed by turning the automatic return lever 49 of the threaded pipe 48. Rotation stopper 5
0 is attached to the latch mounting plate 8 of the traveling truck 7, and when the traveling truck 7 moves to the left with respect to the rail member 5 and the lower claw 37 of the latch 36 comes off the dot positioning stopper 43, the latch 36 The tension spring 42 acts to prevent the rotation from being rotated clockwise due to the biasing force of the tension spring 42.

An angled bracket 51 is attached to the upper part of the support member 6.
A pair of support plates 53, which rotatably support a pulley 52, are fixed to the horizontal plates in parallel. An original position stopper 54 is attached to the upper part of the vertical plate of the bracket 51 so that its position can be adjusted, and the end of the original position stopper 54 on the side of the traveling carriage 7 is fixed when the traveling carriage 7 returns to its original position on the rail member 5. It collides with a cushion 55 provided on the traveling trolley 7 to soften the impact. Furthermore, a wire rope 56 is inserted through a hole (not shown) provided in the axial center of the original position stopper 54, and one end of the wire rope 56 is fixed to the traveling carriage 7 through a cushion 55. A weight 57 is attached to the other end of the wire rope 56 suspended from the pulley 52, and the traveling truck 7 is constantly subjected to a tensile force toward the support member 6 by the weight 57. 58 is a protection pipe attached to the support member 6, and a weight 57 can move up and down inside the protection pipe. The lower end of the protection pipe 58 is sealed, and when a weight 57 descends to return the traveling carriage 7 to its original position, the lower end of the protection pipe 58 is sealed, and when the weight 57 is lowered to return the traveling carriage 7 to its original position, the descending speed of the weight 57 is slowed down.
Contains the amount of liquid necessary to absorb the shock caused by the stoppage.

A protruding dog 59 is attached to the traveling cart 7 on the opposite side of the cushion 55, and this dog 59 comes into contact with a limit switch 60 attached to the upper part of the sliding portion 46a of the stopper mounting member 46, turning on the limit switch 60. When this is done, the gun cylinder 19 stops at the top dead center position.

62, 62a, 62b, and 62c are lower electrodes, which are provided according to the dot positions of the workpiece W.

Next, the operation of this embodiment will be explained.

FIG. 6 shows a state in which the traveling carriage 7 is at the starting position and the upper electrode 21 is raised to the top dead center. In this state, the original stopper 54 is in contact with the cushion 55, and the lower pawl 37 of the latch 36 is in contact with the cushion 55.
The tip of the latch 36 is in contact with the stop surface 43a of the dot positioning stopper 43, and the lower surface of the upper claw 38 of the latch 36 is in contact with the original position stopper 44. On the other hand, the vertical groove 24 of the hook portion 23 of the hook 22
The lower surface 24b of the cam follower 3 of the feed link 28
0 is pushed up and the feed link 28 is rotated clockwise, and the claw portion 31a of the feed claw 31 is free.

Next, in this state, when the compressed air in the gun cylinder 19 is switched and the cylinder rod 20 is lowered, the upper electrode 21 is lowered as shown in FIG. Pressurize.

Meanwhile, as Rod 20 descends, Rod Base 2
6, the link rod 25 is pushed down, so that the hook 22 is lowered. When the hook 22 descends, the upper end surface 24a of the vertical groove 24 of the hook portion 23 comes into contact with the calf follower 30 of the feed link 28 and pushes the cam follower 30 down. As a result, the feed link 28 rotates counterclockwise about the support shaft 29, causing the feed claw 31 pivotally attached to the tip of the long arm 28b to rotate counterclockwise. At this time, the cam follower 32 of the feed claw 31 moves while being guided by the cam surface 33a of the feed claw guide cam 33, and the tip of the claw portion 31a of the feed claw 31 is moved by the tension spring 3.
4 and is pushed down by the inclined surface 35c, and moves to the left while rotating clockwise around the pin 61.

As a result, in the state where the lower electrode 21 presses the first impact point of the workpiece W1, the original position stopper 5
4 is in contact with the cushion 55, and the tip of the lower claw 37 of the latch 36 is in contact with the stopper surface 43a of the dot positioning stopper 43.
The lower surface of the upper claw 38 of No. 6 is in contact with the original position stopper 44. In addition, since the upper surface 24a of the vertical groove 24 of the hook portion 23 of the hook 22 pushes down the cam follower 30 of the feed link 28 and rotates the feed link 28 in the counterclockwise direction, the claw portion 31a of the feed pawl 31 acts as a feed pawl. First stopper surface 3 of stopper 35
It is in a state away from 5a.

In the above state, when the compressed air in the gun cylinder 19 is switched to raise the cylinder rod 20, the link rod 25 is pushed up via the rod base 26, as shown in FIG. 3, so that the hook 22 is raised. When the hook 22 rises, the lower end surface 24b of the vertical groove 24 of the hook portion 23 comes into contact with the cam follower 30 of the feed link 28 and pushes the cam follower 30 upward. For this reason, the sending link 28
rotates clockwise about the support shaft 29, and rotates the feed pawl 31, which is pivotally attached 61 to the tip of the long arm 28b, clockwise. As described above, the feed pawl 31 moves as the cam follower 32 is guided by the cam surface 33a of the feed pawl guide cam 33, and the tip of the pawl portion 31a of the feed pawl 31 touches the feed pawl stopper 3.
5 comes into contact with the first stopper surface 35a of No.5. Hook 2
2 further rises, the feed pawl 31 is further rotated clockwise as shown in FIG. Support shaft 29
receives a force in the direction opposite to the moving direction of the feed claw 31.
For this reason, the traveling bogie 7 to which the support shaft 29 is attached
is guided by the upper regulating member 13 and lower regulating member 14 on the guide rail 2, and moves in a direction away from the feed pawl stopper 35 (to the left in FIG. 1) against the tensile force of the weight 57.

When the traveling cart 7 moves to the left, the latch 36 also moves in the same direction, and the upper claw 38 moves away from the original position stopper 44, and the tip of the lower claw 37 moves away from the stopper surface 43a of the dot positioning stopper 43 and tilts. It slides on the surface 43b and moves while rotating counterclockwise about the support shaft 39. When the lower pawl 37 passes the second stopper surface 43c of the dot positioning stopper 43, the latch 36 is moved around the support shaft 39 by the biasing force of the tension spring 42 attached to the upper pawl 38 and the latch mounting plate 8. Rotated clockwise. And Latch 36
When rotated slightly, the upper surface of the upper pawl 38 comes into contact with the rotation stopper 50. Therefore, the latch 36 stops rotating at a position where the tip of the lower claw 37 is slightly lower than the top of the second stopper surface 43c of the dot positioning stopper 43. cylinder rod 20
When the feed link 28 further rises and the feed link 28 rotates clockwise, the feed pawl 31 comes off the first stop surface 35a of the feed pawl stopper 35, as shown in FIG. As a result, the force that was pushing the traveling carriage 7 to the left disappears, the traveling carriage 7 is pulled to the right by the action of the weight 57, and the tip of the lower pawl 37 of the latch 36 moves to the second position of the dot positioning stopper 43. It stops in a state where it is pressed against the stopper surface 43c.

Next, when the compressed air sent to the gun cylinder 19 is switched and the cylinder rod 20 and the hook 22 are lowered, the upper end surface of the vertical groove 24 of the hook 22
4a contacts the cam follower 30 of the feed link 28, and then pushes the cam follower 30 down. Therefore, the feed link 28 rotates counterclockwise about the support shaft 29, and moves the feed claw 31, which is pivotally attached 61 to the tip of the long arm 28b, to the left.
That is, after the tip of the claw portion 31a of the feed pawl 31 is separated from the first stop surface 35a of the feed pawl stopper 35, the feed pawl 31 is pushed down by the inclined surface 35c against the biasing force of the tension spring 34, and rotates clockwise around the pin 61. Move to the left while rotating.

As the cylinder rod 20 further descends, the feed link 28 further rotates counterclockwise.
The tip of the claw portion 31a of the feed claw 31 is the feed claw stopper 3
It comes off from the second stopper surface 35b of No.5. Feed claw 3
1 is rotated counterclockwise by the tension spring 34 at the same time that the claw portion 31a is removed from the second stopper surface 35b, and the cam follower 32 comes into contact with the cam surface 33a of the feed claw guide cam 33 and stops, causing the gun cylinder 19 to stop. Accurately set the second hitting point.

When the cylinder rod 20 is still lowered, the upper electrode 21 at the lower end is moved to the lower electrode 62 at the second dot position.
Since the workpiece W1 is pressed into contact with a, spot welding is performed in this state.

In the same manner as above, when the cylinder rod 20 moves up, the traveling carriage 7 moves to the left, and when the cylinder rod 20 descends, the positioning of the traveling carriage 7 (therefore, the gun cylinder 19) and spot welding are performed automatically in sequence. It can be done.

When the welding at the final welding point position is completed, the cylinder rod 20 is raised, the hook 22 rotates the feed link 28 clockwise, and the carriage 7 is moved to the left. However, there is an automatic return stopper 45 at the forward end of the traveling carriage 7, and the upper pawl 38 of the latch 36 comes into contact with this stopper 45, and the latch 36 is rotated counterclockwise (see FIGS. 1 and 7). ). Therefore, the latch 36 rotates until the lower pawl 37 comes off the stop surface of the dot positioning stopper at the final dot position and comes into contact with the pin 41. On the other hand, the feed link 28 is rotated clockwise due to the rise of the hook 22.
is moved along the cam surface 33a of the feed pawl guide cam 33 to a position where the tip of the pawl portion 31a of the feed pawl 31 is below the lower ends of the feed pawl stoppers 35, 35', .

As mentioned above, the final position positioning stopper 43n and the latch 36 are disengaged, and the feed claw 3
When the first claw portion 31a is located below the feed claw stopper 35n, the traveling carriage 7 is pulled by the weight 57 and returns to its original position. When the carriage 7 returns to its original position, the upper claw 38 of the latch 36, which had been inverted, hits the original position stopper 44, as shown in FIG.
Rotate clockwise to return to starting position.

Note that when the workpiece, like the workpiece W1 shown in FIG. In order to prevent
It is necessary to vertically raise the lower electrode 21 by the height l of the peak of the workpiece W1. That is, the lower electrode 2
1 rises from the first hitting position, the traveling carriage 7 needs to be stopped until it rises by at least l. This stop is caused by the play between the vertical groove 24 of the hook 22 and the cam follower 30 of the feed link 28 (the play between the lower end surface 24b of the vertical groove 24 and the cam follower 30).
) and the first position of the feed pawl stopper 35.
This is done by appropriately setting the play between the stopper surface 35a and the tip of the claw portion 31a of the feed claw 31.

Furthermore, if it is necessary to move the dot position in a direction perpendicular to the moving direction of the traveling carriage 7 (direction of arrow A or arrow B in FIG. 2), the upper regulating member 13 and the lower regulating member 14 are moved as necessary. This is done by molding in the direction of movement.

As described above, the present invention provides a spot welding machine with a rail member having substantially the same length as the length of a workpiece to be welded and mounted substantially horizontally, and a running track member attached to this rail member. a traveling carriage supported by a rail member, which travels with its movement direction regulated by a direction regulating member; the traveling carriage is provided with a feed link and a dot positioning latch that are rotated by the raising and lowering of the gun cylinder and the cylinder rod; The rail member is provided with a stopper that stops the rotation of the feed link and moves the traveling carriage when the cylinder rod is raised, and a hitting point positioning stopper that engages with the hitting point positioning latch to stop the moving traveling truck at the hitting point position. The following effects can be achieved by being movable and providing a number corresponding to the number of dots, and by providing a means for returning the traveling cart that has reached the final dot position on the rail member to the initial dot position. .

Since the workpiece is fixed and the gun cylinder moves, the equipment space can be made approximately the same size as the workpiece.

Since the traveling trolley travels while being guided by the traveling direction regulating member attached to the rail member, a desired planar hitting point can be set.

By changing the positions of the stopper that stops the rotation of the feed link and the stopper that determines the position of the workpiece, the position of the workpiece hitting point can be changed, and by bending the guide rail and the traveling direction regulating member, it is also possible to hit a curved surface.

By providing play between the time when the cylinder rod begins to rise and the time when the feed link contacts the stopper that stops its rotation, the cylinder rod can be made to move in three dimensions.

By providing the automatic return means, the traveling carriage can automatically return from the final dot position to the first dot position.

[Brief explanation of the drawing]

The figures show one embodiment of the present invention, and Fig. 1 is a front view of the indexing section of the spot welding machine in a state where the cylinder rod is lowered and the first welding point position of the workpiece is pressurized, and Fig. 2 is the same as Fig. 1. − Linear view,
Figure 3 is a front view of the indexing section of the spot welding machine with the cylinder rod raised to release the pressurized state at the first welding point position of the workpiece, and Figure 4 is a front view of the spot welding machine with the cylinder rod further raised. 5 is a front view of the indexing section of the spot welding machine with the cylinder rod raised to top dead center; FIG. 6 is a front view of the indexing section of the spot welding machine at the starting position; FIG. FIG. 8 is an explanatory diagram showing the operation of the latch after welding at the final welding point position, and FIG. 8 is an explanatory diagram showing the operation of the latch when the traveling carriage is returned from the final welding point position to the starting position. 5...Rail member, 7...Traveling trolley, 13...
Upper regulating member, 14... Lower regulating member, 19...
Gun cylinder, 20... Cylinder rod, 21...
...upper electrode, 28... (index) feed link,
31...Feeding pawl, 35, 35', 35''...Feeding pawl stopper, 36...Dot positioning latch, 43,
43', 43''...Dot positioning stopper, 45...
...Automatic return stopper, 54...Original position stopper,
57... Weight, W1, W2... Work.

Claims (1)

[Claims] 1. In a spot welding machine having a gun cylinder in which a cylinder rod with an electrode attached can be moved up and down by the action of fluid, a rail member having approximately the same length as the length of the workpiece to be welded, and a welding rod attached to this rail member are used. a traveling bogie whose movement direction is regulated by a traveling direction regulating member and supported movably in the longitudinal direction by a rail member;
This traveling carriage is provided with a feed link and a dot positioning latch which are rotated by the rise and fall of the gun cylinder and the cylinder rod, and the rail member is provided with a feed link that stops rotating when the cylinder rod is raised and moves the traveling dolly to the next dot point. A stopper for moving in the position direction and a dot positioning stopper for engaging with the dot positioning latch and stopping the moving carriage at the dot position are movable in mounting position and are provided in a number corresponding to the number of dots on the workpiece; A self-propelled spot welding machine with a gun, characterized in that it is provided with means for returning a traveling cart that has reached a final welding point position on a rail member to an initial welding point position.