JPS632233Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention is applicable to seam welding of the joint of an object to be welded consisting of a main body and a lid, such as a fuel tank for a vehicle. The present invention relates to a welding speed switching device for a seam welding machine, which is capable of switching the welding speeds of a straight line portion and an arcuate portion of a welding line to appropriate welding speeds, respectively.

(Prior art) For example, when the welding line of the workpiece is composed of a straight part and a circular part, such as an automobile gasoline tank consisting of a cylindrical body and a lid, it is necessary to obtain a good seam weld. Set the welding speeds for the straight and arcuate parts of the welding line to appropriate welding speeds (relatively high speed for the straight part and slow for the arcuate part), and adjust the welding speed appropriately depending on the straight and arcuate parts each time. It is desirable to switch to perform seam welding.

Therefore, as a welding speed switching means for switching the welding speed of the seam welding machine, as shown by the imaginary line in FIG. A dog plate 46 formed in the shape of the welding line on the side opposite to the rotary base plate 13 rotatably supported on the upper part of the link arm 12 and formed in the shape of the welding line of the objects to be welded W, W'. is mounted so as to be coaxial and parallel to the rotating board 13, and a low-speed dog 47 and a high-speed dog 48 are mounted at appropriate positions on the dog plate 46,
It is known that a low-speed limit switch 50 and a high-speed limit switch 51 are arranged at appropriate positions corresponding to the dogs 47 and 48, so that the straight part of the weld line can be seam welded at high speed, and the circular arc part can be seam welded at low speed. It is being In addition, in Figure 1, 4
9 is a dog for the original position, and 52 is a limit switch for the original position.

That is, when using the conventional welding speed switching means, the straight part of the weld line of the workpieces W, W' is seam welded at high speed, and the low speed limit switch 50 is switched to the low speed dog 47 just before reaching the circular arc part.
contact, the welding speed is switched to low speed, and the arc portion is welded. After welding of the arcuate portion is completed, and almost at the same time as welding of the straight portion is started, the high speed limit switch 51 comes into contact with the high speed dog 48, the welding speed is switched to high speed, and the welding of the straight portion is performed. . Hereinafter, when welding of all the weld lines of the objects to be welded W, W' is completed in this manner, the in-situ limit switch 52 comes into contact with the in-situ dog 49, and one welding cycle is completed.

However, in such conventional welding speed switching means, whenever the shape of the weld line of the workpiece changes, the dog plate 46 must be newly designed to match the shape of the weld line of the workpieces W, W'.・
It has to be manufactured, which is very disadvantageous in terms of cost. In addition, the low speed dog 47, the high speed dog 78, the low speed limit switch 50, and the high speed limit switch 51 are connected to the workpiece W,
Each mounting position must be set in accordance with the shape of the circular arc portion of the weld line of W', and there is a problem in that it is troublesome to deal with changes in the shape of the weld line.

(Purpose of the invention) An object of the invention is to provide a welding speed switching device for a seam welding machine that solves the above-mentioned problems and can switch the welding speed with an extremely simple configuration.

(Structure of the invention) Therefore, the structure of the invention is such that the welding speed switching area of the welding line is set on a rotating board that is movably and rotatably supported by the seam welding machine main body and is formed in the shape of the welding line of the workpiece. A welding speed switching area transmission means is provided for transmitting the welding speed switching area, and the welding speed switching area is transmitted through the welding speed switching area transmission means to a guide rail member that engages with the rotating board and guides the workpiece along the welding line. The present invention is characterized in that it includes a welding speed switching area detection means for detecting the welding speed switching area.

(Function) As described above, the welding speed switching area transmission means is directly provided on the rotating board formed in the shape of the weld line of the workpiece, and the welding speed switching area transmission means is provided on the guide rail member side via the welding speed switching area transmission means. If the welding speed switching area detection means is configured to detect the welding speed switching area of the weld line of the workpiece, welding can be performed without providing a dog plate formed in the shape of the weld line of the workpiece as in the past. Seam welding can be performed by appropriately switching the welding speed for the straight and arcuate parts of the line to an appropriate welding speed set in advance, so even if the shape of the weld line changes, the weld line can be adjusted each time as before. There is no need to newly design and manufacture a dog plate to match the shape of the dog. Moreover, the welding speed switching area detecting means provided on the guide rail member only needs to be installed at one location on the extension of the welded part of the workpiece or in the vicinity. In this case, even if the shape of the weld line changes,
There is no need to change the mounting position of the welding speed switching area detection means.

(Embodiment) An embodiment of the present invention will be described below based on FIGS. 1 to 6. An upper electrode 2 and a lower electrode 3 are each rotated at an appropriate height position on the seam welding machine main body 1. possible. The upper electrode 2 is
It is provided so as to be movable up and down in the direction AA' in FIG. 1 by means of a pressure cylinder device (not shown) fixed to the upper part of the seam welding machine main body 1. Further, the lower electrode 3 is fixedly supported by a bracket (not shown) horizontally fixed to the seam welding machine main body 1.

Reference numerals 4 and 5 denote brackets fixed horizontally to the seam welding machine body, and on the side of the bracket 4 of the seam welding machine body 1, as shown in FIG. They are spaced apart and fixed to each other. Reference numeral 8 denotes a jig movably provided in the seam welding machine main body 1, and between the brackets 67, the link arm 1 of the jig 8 is connected by a hinge pin 9.
0 is connected to the link arm 10 so as to be freely rotatable in the horizontal direction, and a link arm 12 is also connected to the link arm 10 through a hinge pin 11 so as to be freely rotatable in the horizontal direction.

Reference numeral 13 denotes a rotating board formed in a shape that matches the shape of the welding line consisting of a straight line part and a circular arc part of the objects to be welded W, W'.
It is rotatably supported on the top of the. Rotating board 1
3, a pedestal 14 for placing, positioning and fixing the objects W, W' to be welded is elastically supported via a plurality of floating mechanisms 15.

Reference numeral 16 denotes an arm fixed to a proper position on the link arm 12. A hollow bracket 17 is fixed to the horizontal portion of the upper end side of the arm 16 and extends vertically so as to coincide with the center line of the rotary base plate 13. A clamp member 18 for clamping the objects W, W' to be welded is fitted into the hollow bracket 17 so as to be movable up and down, and 19 is a clamp cylinder device for moving the clamp member 18 up and down. , are arranged on the upper part of the hollow bracket 17.

20 is a guide rail (guide rail member) for guiding the objects to be welded W, W' along the welding line.
As shown in FIG. 2, the brackets 4 and 5 are fixedly supported horizontally at the tips of the brackets 4 and 5 fixed to the seam welding machine main body 1. A guide groove 2 formed in the guide rail 20 so as to extend in the longitudinal direction thereof.
As shown in FIGS. 3 and 4, a cam stopper 22 is provided at a suitable location on the inner surface of the cam stopper 1.
A plurality of ratchets 23 are disposed at appropriate positions on the upper part of the guide rail 20 so as to be freely retractable, and the ratchets 23 are always resiliently biased upward by a biasing means such as a spring (not shown).

24 is a welding speed switching device, and this welding speed switching device 24 is located on or near the extension line of the contact point (seam welding part) between the upper electrode 2 and the lower electrode 3, and is connected to the seam welding machine of the guide rail 20. Main body 1
The equipment is located on the side. That is, an arm 27 is supported by a bracket 25 fixed to the seam welding machine main body 1 side of the guide rail 20 via a hinge pin 26 so as to be rotatable in the DD' direction in FIG. Reference numeral 28 denotes a stopper flange which comes into contact with the guide rail 20 and suppresses the rotation of the arm 27 in the direction D in FIG. 5, and is provided on the upper part of the arm 27. Stopper flange 28
A cam 29 is attached facing upward, and a tapered portion 3 is attached to the upper part of the cam 29 on the rotating board 13 side.
0 is formed.

Reference numeral 31 denotes an L-shaped dog attached to the lower part of the arm 27, and an inclined surface 32 is formed at the lower part of the L-shaped dog 31, as shown in FIG. 33
is a bracket mounted at a position lower than the hinge pin 26 of the bracket 25, and is attached to the bracket 33.
One end of a bolt 34 screwed onto the arm 27 penetrates and protrudes through a long hole (not shown) formed in the arm 27 .

Reference numeral 35 denotes a spring attached to the protrusion side of the bolt 34. The spring 35 constantly urges the arm 27 to rotate in the direction D in FIG. 5 using the hinge pin 26 as a fulcrum. Due to the force, the arm 27 is held in a state where the flange 28 is in contact with the guide rail 20. 36
is a lock nut screwed onto one side of the bolt 34,
37 is a nut screwed onto the other side of the bolt 34;
Reference numerals 8 and 39 are spring clasps mounted on the bolt 34.

40 is the arm 2 with the hinge pin 26 as a fulcrum.
When the welding speed switch 7 rotates in the direction D' in FIG. It has a function as a switching area detection means. limit switch 4
0 is attached to a bracket 41 fixed to the lower part of the guide rail 20.

Reference numeral 42 is a copying plate for guiding the straight part of the welding line of the objects to be welded W, W' by engaging with the ratchet 23 provided on the upper part of the guide rail 20, and is a tracing plate for guiding the straight part of the weld line of the workpieces W, W'. It is fixedly attached to the Numeral 43 is a half-moon cam pin that engages with the cam stopper 22 fixed to the inner surface of the cam groove 21 and guides the arcuate portion of the welding line of the objects to be welded W, W'. The vertical surface of the U-shaped cam groove 44 formed in the half-moon cam pin 43 is provided at a position corresponding to the arcuate portion of the welded objects W, W', and more specifically, the vertical surface of the U-shaped cam groove 44 formed in the half-moon cam pin 43 is aligned with the straight portion of the weld line to be welded next. fixed in parallel.

Reference numeral 45 denotes a dog having a circular arc portion similar to the shape of the circular arc portion of the welding line of the objects to be welded W, W', and a portion of the dog 45 protrudes to the outside of the rotary substrate 13 at each circular arc portion of the rotary substrate 13. It is installed like this. The dog 45 has a function as a welding speed switching range transmitting means for transmitting the welding speed switching range of the weld lines of the objects W, W' to the limit switch 40 side.

To explain the operation of the welding speed switching device of the seam welding machine configured in this way, first, the objects to be welded W, W' are placed on the pedestal 29 and positioned.
The clamp cylinder device 19 is operated to clamp and fix the objects to be welded W, W' by the clamp member 18. Next, since the upper electrode 2 and the lower electrode 3 are in an open state, that is, the upper electrode 2 is located at the rising end, a pressurizing cylinder device (not shown) fixed to the upper part of the seam welding machine main body 1 is activated. actuates to lower the upper electrode 2 in the direction A′ in FIG.
The welded parts of the objects W and W' are held between an upper electrode 2 and a lower electrode 3.

Thereafter, both the electrodes 2 and 3 are rotated while being energized and pressurized to first weld the straight portions of the weld lines of the objects to be welded W and W'. Work to be welded W,
When welding of the straight part of the welding line W′ is completed, the half-moon cam pin 43 that guides the arcuate part of the welding line to be welded next passes through a ratchet (not shown) disposed at an appropriate position in the guide groove 21. It comes into contact with the cam stopper 22. At this time, the ratchet (not shown) rises to support the half-moon cam pin 43 from behind. Therefore, at that position, the half-moon cam pin 43 is rotationally displaced to a rotational position where the U-shaped cam groove 44 engages with the cam stopper 22. That is, the arc portion of the welding line is welded with the half-moon cam pin 43 as the center of rotation.

When the welding of the arcuate portion of the welding line approaches the end, a copying plate 42 guides the straight portion of the welding line to be welded next.
comes into contact with the ratchet 23, and at the same time the welding of the arc portion of the weld line is completed, the copying plate 42 passes through the ratchet 23. After the tracing plate 42 passes through the ratchet 23, the ratchet 23 immediately rises, and as the ratchet 23 rises, the tracing plate 42 engages with the ratchet 23 to guide the straight portion, and welding of the straight portion is performed.

On the other hand, when the welding of the straight section approaches the end, the dog 45, which is the welding speed switching area transmission means, moves to the cam 29.
As the welding progresses, the cam 29 is pushed rearward (to the left in FIG. 5) by the dog 45. When the cam 29 is pushed backward, the arm 27 pivots around the hinge pin 26.
is resisting the elastic force of the spring 35 in Fig. 5.
Accordingly, the L-shaped dog 31 attached to the lower part of the arm 27 also rotates in the direction D' in FIG. 5 and hits the limit switch 41. Turns on. When the limit switch 41 is turned on, the welding speed is switched to a low speed preset according to the arc portion of the welding line, and welding of the arc portion is performed at a low speed.

When welding of the arc portion is completed, the dog 45 gradually moves away from the cam 29, and the arm 27 rotates in the direction D in FIG. When the arm 27 comes into contact with the guide rail 20, the rotation of the arm 27 is stopped. Here, when the arm 27 rotates in the direction KD in FIG. 5, the L-shaped dog 31 separates from the limit switch 40 as the arm 27 rotates, so the limit switch 40 is turned off. When the limit switch 40 is turned off, the welding speed is switched to a high speed preset according to the straight portion of the welding line, and welding of the straight portion is performed at high speed. Hereinafter, in this way, seam welding of the weld line is performed sequentially at high and low speeds according to the straight parts and circular arc parts of the objects W and W' to be welded,
A welding cycle ends when all welds are completed.

As an additional note about the switching position between low and high welding speeds, when welding from a straight section to an arc section, the position should be approximately 20 mm before the end of the straight section, and when welding from a straight section to a straight section. When welding in a straight section, it is desirable to switch the welding speed at a position approximately 20 mm from the beginning of the straight section. Therefore, Dog 45
When attaching the dots 45, the dogs 45 may be attached to each arcuate portion of the rotary base plate 13 so that the welding speed is switched at the above-mentioned switching position. For example, the dog 45 may have straight portions of appropriate lengths attached to both ends of its arcuate portion.

The present invention is not limited to the above-mentioned embodiments. For example, the limit switch 40 is mounted on the guide rail 20, and the limit switch 40 is
The knob may be configured to directly contact the dog 45, thereby detecting the welding speed switching region. Further, in the embodiment, a limit switch is used as the welding speed switching area detection means, but instead of the limit switch, for example, a photoelectric switch, a proximity switch, etc. may be used for optical or magnetic detection.

(Effect of the invention) As explained above, according to the invention, the guide rail member that guides the welding line of the workpiece is welded via the welding speed switching area transmission means disposed on the rotating board side. The structure is equipped with a welding speed switching area detection means that detects the speed switching area, so even if the welding line shape of the workpiece changes, it can be adjusted each time according to the welding line shape, like a conventional dog plate. There is no need to newly design and manufacture, and manufacturing costs can be reduced.

Moreover, the welding speed switching area detecting means only needs to be installed at one location on the extension of the welding part or in the vicinity thereof, and even if the shape of the weld line of the workpiece changes, the welding speed switching area detecting means Since there is no need to change the mounting position, it is possible to easily respond to changes in the shape of the line to be welded.

[Brief explanation of the drawing]

FIG. 1 is a schematic side view showing an embodiment of the present invention;
Fig. 2 is a schematic plan view of Fig. 1, Fig. 3 is an enlarged front view of main parts showing the guide rail according to the present invention, Fig. 4 is a plan view of Fig. 3, and Fig. 5 is B of Fig. 3. FIG. 6 is an enlarged sectional view taken along line -B, and is a view taken in the direction of arrow C in FIG. 5. 1... Seam welding machine main body, 2... Upper electrode, 3
... lower electrode, 13 ... rotary board, 20 ... guide rail, 29 ... cam, 40 ... limit switch, 45 ... dog.

Claims (1)

[Scope of utility model registration request] A seam welding machine that holds a workpiece between an upper electrode and a lower electrode and performs welding while applying current and pressure to the workpiece through both electrodes, which is movable and rotatable in the seam welding machine main body. supported by
a rotating board formed in the shape of a welding line of the object to be welded; and a guide rail member provided on the seam welding machine main body that engages with the rotating board to guide the object to be welded along the welding line. The rotating board is provided with a welding speed switching area transmitting means for transmitting the welding speed switching area of the weld line of the workpiece, and the guide rail member is provided with the welding speed switching area transmitting means. A welding speed switching device for a seam welding machine, characterized in that a welding speed switching area detection means for detecting the welding speed switching area via a welding speed switching area is provided.