JPH0442068Y2 - - Google Patents

Description

[Detailed description of the invention] (Field of industrial application) The present invention provides a copying cam having a cylindrical cam portion around it corresponding to the shape of the welded part of the workpiece, and supports the workpiece on the cam. The present invention relates to an automatic copying device for a seam welding machine, which feeds the welded part between a pair of upper and lower roller electrodes provided in the seam welding machine.

(Prior art) Conventionally, in this type of device, the
As seen in Publication No. 39183, the copying cam is rotated around a vertical shaft attached to the copying cam, and in order to ensure the freedom of movement of the cam in the horizontal direction, the cam is rotated around the vertical shaft attached to the copying cam. The cam is pivoted at the tip of a double hinge arm that swings horizontally through the cam, and is guided by fixed-side guide means that sandwich the cylindrical cam part surrounding the cam from the inside and outside. The cam section is designed to give a motion similar to that of the cam section by combining with the motion.

(Problems to be solved by the invention) The above device uses a double hinge arm, which makes the device large and expensive. It is desired to do so.

An object of the present invention is to provide a small and inexpensive device that meets such demands.

(Means for Solving the Problems) In order to achieve the above object, the present invention provides a copying cam having a cylindrical cam portion around the circumference corresponding to the shape of the welded part of the workpiece, and places the workpiece on the cam. The cam is supported so that the welded part is fed between a pair of upper and lower roller electrodes provided in a seam welding machine, and the cam is supported rotatably and horizontally on a fixed table, A drive motor having a chain attached to its circumferential surface and a sprocket on an output shaft that engages with the chain on the fixed table, and a drive motor that abuts the other inner and outer circumferential surfaces of the cam part to connect the cam part to the sprocket. It is characterized by having a cam guide attached to it.

(Function) When the sprocket is rotated by the drive motor, a driving force is applied to the copying cam via the chain attached to the cam portion, and the sprocket and the cam guide use the holding portion of the cam portion as a guide to rotate the copying cam. The copying cam moves on the fixed table to follow the cam portion, and the workpiece on the copying cam is given a movement that follows the shape of the welded portion, so that the welded portion is automatically fed between the roller electrodes.

(Example) Referring to FIG. 1, 1 indicates a seam welding machine equipped with a pair of upper and lower roller electrodes 2 and 3. The upper roller electrode 2 is movable up and down by a pressure cylinder 4, and The welding area Wa around the workpiece W such as an automobile fuel tank is sandwiched between the electrodes 2 and 3, and in this state, the electrodes 2 and 3 are rotated to seam weld the welding area Wa. did.

As shown in FIG. 2, the workpiece W is set on a copying cam 5 having a circumferential cylindrical cam portion 5a corresponding to the shape of the welding part Wa via a workpiece receiver 6. The cam part 5a is rotatably and horizontally movably supported on a fixed table 8 at the bottom of the seam welding machine 1 via a ball 7 on the lower surface of the cam part 5a, and a chain 9 is attached to one of the inner and outer peripheral surfaces of the cam part 5a, for example, the outer peripheral surface. At the same time as attaching the fixed table 8
, a drive motor 11 having a sprocket 10 on an output shaft that engages with the chain 9, and the cam portion 5.
A cam guide 12 consisting of a guide roller that comes into contact with the inner circumferential surface of the sprocket a and sandwiches the cam portion 5a between the sprocket 10 and the sprocket 10 is attached.

During seam welding, the feed direction of the welding area Wa by the rotation of the roller electrodes 2 and 3 (arrow A in Fig. 2)
The sprocket 10 is rotated counterclockwise in FIG. 2 in synchronization with the electrodes 2 and 3 in order to move the copying cam 5 in the same direction as the sprocket 10. Using the holding part of the cam part 5a by the cam guide 12 as a guide, the cam part 5a moves along the cam part 5a by the driving force transmitted from the sprocket 10 through the chain 9, and the workpiece W is attached to the welding part Wa. A movement synchronized with the rotation of the electrodes 2 and 3 is applied, and the welding portion Wa is automatically fed into the electrodes 2 and 3.

(Effect of the invention) As described above, according to the invention, the copying cam is moved along the cam part on a fixed table by rotation of the sprocket that engages with the chain attached to the cam part, and the welded part of the workpiece is seamed. In addition to being able to reliably feed the welding machine between the roller electrodes, there is no need for a conventional double hinge arm that pivotally supports the copying cam, which has the effect of making the device smaller and cheaper.

[Brief explanation of the drawing]

Figure 1 shows a seam welding machine equipped with the proposed device.
A side view of the example, FIG. 2 is a bottom view taken along the line -- in FIG. 1... Seam welding machine, 2, 3... Roller electrode,
5... copying cam, 5a... cam part, 8... fixed table, 9... chain, 10... sprocket, 11... drive motor, 12... cam guide,
W...Work, Wa...Welding part.

Claims (1)

[Scope of utility model registration request] A copying cam having a circumferential cylindrical cam part corresponding to the shape of the welded part of the workpiece is provided, the workpiece is supported on the cam, and the welded part is sent between a pair of upper and lower roller electrodes provided in the seam welding machine. In such a device, the cam is rotatably and horizontally movably supported on a fixed table, a chain is attached to one of the inner and outer peripheral surfaces of the cam part, and a chain is attached to the fixed table on the output shaft that engages with the chain. An automatic copying device for a seam welding machine, characterized in that a drive motor having a sprocket and a cam guide that comes into contact with the other inner and outer circumferential surfaces of the cam portion and sandwich the cam portion between the sprocket and the sprocket are attached. .