JPH01157781A - Automatic resistance welding equipment - Google Patents

Abstract

PURPOSE:To perform a series of welding processes fully automated by a simple structure by providing a means to execute the processes such as conveyance, positioning and welding of works with full automation. CONSTITUTION:When the couple of works 1 and 2 to be welded are mounted on prescribed positions of a conveyor 20, a stopper 42 advances from the outlet side of electrodes 17 and 18 of a welding machine 16 simultaneously with traveling of the conveyor 20 and the works 1 and 2 advance on the conveyor 20 and abut on the stopper 42. By this method, a width shifting driving means 25 is actuated and the couple of works 1 and 2 are allowed to approach each other and end faces to be welded are superposed by the prescribed width. When the electrodes 17 and 18 and a clamp roller 51 then press the works 1 and 2 simultaneously to maintain this lap allowance, the stopper 42 shunts from the works 1 and 2 which become conveyable. The electrodes 17 and 18 then rotate and a clamp movable carriage 61 advances simultaneously to advance the works 1 and 2. At this time, a welding current is applied between the electrodes 16 and 17 and the continuous welding can be performed.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to an automatic resistance welding device for joining a pair of workpieces, and is particularly suitable for fully automatically carrying out processes such as transporting, positioning, and welding of the workpieces. Regarding automatic resistance welding equipment.

[Conventional technology]

2. Description of the Related Art Metal products used, for example, in the body of an automobile or a part thereof, are usually made by punching out a thin plate by press working. Generally, scraps punched out by press processing are used for reuse, for example, as shown in Figure 12.
As shown in FIG. 13, the pieces of scrap material 1 and 2 are seam welded by overlapping their opposing end surfaces to a certain width, and are then made into a product and reused.

Conventionally, a seam welding device as shown in FIGS. 14 to 16 has been used as a device for joining the scraps together. In FIG. 0, a pair of guide rails 4 are mounted on a base 3. A workpiece moving table 5 is movably provided on these guide rails 4. The workpiece moving table 5 is moved by a drive cylinder 6 fixed to the base 3 via a drive shaft 7. At one end of the workpiece moving table 5, there are provided two pairs of entry side clamps 8 and two outlet side clamps 9 on the left and right with respect to the moving direction, each of which is operated by a clamp cylinder 10 fixed to the workpiece moving table 5.

Workpieces 1 and 2 on a workpiece mounting table 11 provided on the upper part of the workpiece moving table 5 are clamped and held. On the other hand, a seam welding machine 1 equipped with a pair of upper and lower electrode shafts 12 and 13 is mounted on the base 3.
4 is provided.

When seam welding the workpieces 1 and 2 using the conventional seam welding device configured as described above, the workpiece mounting table 11
Place the works 1 and 2 on top and insert them under the entry side clamp 8 and the exit side clamp 9, respectively.
is butted against a stopper (not shown) provided between the clamps 8 and 9 to form an overlapped portion necessary for seam welding. After that, the clamp cylinder 10 is operated and the entry side clamp 8 is
and a primary drive cylinder 6 that firmly clamps and holds the workpieces 1 and 2 on the workpiece mounting table 11 with the output side clamp 9.
is activated to move the workpiece moving table 5 forward into the seam welding machine 14, and while feeding the overlapping part of the works 1 and 2 between the electrode wheels 12.13, the electrode shaft 12.13 is given the rotational drive and the necessary stress for welding. Seam welding is performed by applying pressure and welding current.

[Problem that the invention seeks to solve]

However, according to the conventional resistance welding device configured as described above, when positioning and attaching the workpieces 1 and 2, such as the workpieces 1 and 2, on the workpiece mounting table 11, most of the operations are performed manually, and the workpiece 1 After manually moving ゜2 so that its welded end face completely hits the stopper, clamp 8,
It was firmly clamped and fixed at 9. Therefore, there was a problem in that troublesome positioning adjustment was required.

Also, the lamp cylinder 1o is firmly placed on the workpiece moving table 5.
need to be installed in four locations, resulting in a large structure.Moreover, each time welding, the workpiece moving table 5 is moved back and forth between the workpiece setting position and the welding position to perform welding, which improves production efficiency. There was also the problem of not being able to do so.

The present invention has been made in view of the above circumstances, and provides an automatic resistance welding device that has a simple structure, can perform a series of welding processes fully automatically, and can shorten production tact and reduce costs. The purpose is to provide.

[Means for solving problems]

In order to achieve the above object, the present invention is an automatic resistance welding device that performs resistance welding with the end surfaces of a pair of workpieces facing each other and overlapped with a certain width. a conveyor for conveying the work to a welding position, a stopper for stopping the conveyance of the work at the welding position, a drive means for overlapping the welded end surfaces of the work stopped by the stopper by a constant width, and a drive means for overlapping the welding end surfaces of the work by a constant width, The welding machine is configured to include a pair of upper and lower clamp rollers that clamp the workpiece in the vicinity of the welding end face in an openable and closable manner, and a clamp moving table that moves the workpiece clamped by the clamp rollers into and out of the welding machine.

[Effect]

The operation of the present invention with the above configuration will be explained below.

When a pair of workpieces to be welded are placed on a predetermined position on the conveyor, a stopper moves forward from the exit side of the welding machine's electrode at the same time as the conveyor runs, and the workpieces move forward on the conveyor and hit this stopper. come into contact with When the workpieces come into contact with the stopper, the driving means is actuated to bring the pair of workpieces closer to each other, so that the welded end surfaces are overlapped by a certain width. Then, when the electrode and clamp roller simultaneously pressurize the workpiece to maintain this overlap, the stopper retreats from the workpiece and the workpiece can be transported.The electrode rotates in the 0th order, and at the same time, the clamp moving table moves forward to remove the workpiece. advance. At this time, a welding current is applied between the electrodes to perform continuous welding.

In other words, the apparatus according to the present invention can fully automatically perform a series of welding processes including positioning, transporting, and welding the work simply by setting the work on the conveyor.

[Embodiment] Hereinafter, an embodiment of an automatic resistance welding machine according to the present invention will be described with reference to the drawings.

An embodiment of the present invention is shown in FIGS. 1 to 11.

In Figures 1 and 2, a seam welder 1 is attached to the floor 15.
6 is fixed, and this seam welding machine 16 has a disc-shaped upper electrode 17 that is movable in the vertical direction, and this upper electrode 17.
A disk-shaped lower electrode 18 is provided opposite to the lower electrode 18 . These electrodes 17 and 18 are rotated by knurls 17a and 18a, respectively, as shown in FIG.

On the work entry side of the welding machine 16, a pair of left and right conveyors 20 are provided on a support stand 19 fixed on the floor 15, and this conveyor 20 has a plurality of rollers 21 arranged at right angles to the workpiece movement direction. It consists of These rollers 21 are rotationally driven in one direction by a drive source 22 via a torque limiter 23 and a chain 24, and transport a work (not shown) placed on the rollers 21 in the direction of arrow A. Reference numeral 25 is a driving means for narrowing the distance between two works placed on the conveyor 20, and details thereof are shown in FIGS. 3 to 5.

A pedestal 26 is erected on the floor 15 parallel to the rollers 21 across above the conveyor 2o, and a pair of upper and lower guide rails 27 are provided along the pedestal 26. On this guide rail 27, two movable tables 28.29 are guided so as to be movable along the longitudinal direction and at symmetrical positions with respect to the electrodes 17.18. Further, these two movable tables 28.29 are connected to cylinders 32.33 supported by support stands 30.31 which can be locked at arbitrary positions on the guide rail 27, respectively. 33 allows them to move facing each other. Furthermore, arms 34.degree. 35 are fixed to the lower sides of the movable tables 28, 29, respectively, and cam followers 36 are fixed to the tips of these arms 34.degree. 3S, respectively. These cam followers 36 slide and rotate in contact with the edge of the workpiece placed on the conveyor 20 and moving, and firmly guide the edge of the workpiece so that the slight overlap does not open.

Reference numeral 37 is a positioning Z bar for setting the width of a seam joint formed between a pair of workpieces. This Z
As shown in FIGS. 3 to 5, the bar 37 has stoppers 38 and 39 each having a Z-shaped cross section with a predetermined length, which are separated into upper and lower sections, and which pass between the left and right rollers 21 of the conveyor 20 installed side by side. It is installed on the entry side close to the electrodes 17, 18 on the seam weld line. Further, one upper stopper 38 constituting this Z bar 37 is supported at an intermediate portion of the pedestal 26 so that its vertical position can be adjusted, and the other lower stopper 39 is supported by a frame erected on the base 40 of the conveyor 2o. 41 so that the vertical position can be adjusted.

Reference numeral 42 denotes a stopper that comes into contact with the front end surface of the workpiece and stops the workpiece within a plane passing through the pressurizing points of the electrodes 17 and 18, the details of which are shown in FIGS. 6 to 8.

An electrode 17. is attached to the upper arm 43 fixed to the welding machine 16.
A pair of plate cams 44 and 45 are supported symmetrically on both sides of the plate cam 18, and each of these plate cams 44 and 45 has two cam grooves 44a and 45a that are inclined upward from the horizontal direction. Each hole is drilled. These cam grooves 44a, 4
Two pins 48.49 implanted in stoppers 46.47 are slidably engaged with 5a, and the tips of the stoppers 46.47 contact the advancing ends of the pair of left and right workpieces. It is designed for positioning.

These stoppers 46 and 47 are integrally connected so that their tips are positioned on a straight line in a direction perpendicular to the seam weld line, and are moved by a cylinder 50 fixed to the upper arm 43 to follow the movement trajectory of the workpiece. It is now possible to evacuate from above.

Furthermore, optical sensors (not shown) are attached to these stoppers 46 and 47 to detect contact between the stoppers 46 and 47 and the workpiece.

Reference numeral 51 denotes a symmetrical clamp roller that clamps the vicinity of the weld line from above and below when the seam weld line is pinched between the electrodes 17 and 18, and maintains the overlap of the seam weld. It is shown in FIG. 11, and since it is bilaterally symmetrical, one side will be explained.

The upper roller 52 is guided by a guide plate 54 fixed to an upper arm 53 of the welding machine 16 and is rotatably attached to a slide plate 56 that moves up and down with a cylinder 55. A lower roller 57 is opposed to the upper roller 52. is welding machine 1
These lower rollers 57 are rotatably supported by a frame 59 rising from a lower arm 58 of No. 6, and these lower rollers 57 are rotationally driven via a chain 24 by the driving force of a driving source 22 shown in FIG.

A clutch 6 is also provided between the drive source 22 and the lower roller 57.
0 is provided, and by switching the clutch 60, the lower roller 57 can be switched to drive rotation or driven rotation.

That is, when transporting the work, the lower roller 57 sends the work to the welding position and is rotated until the tip of the work comes into contact with the stoppers 46 and 47, but when welding starts, the clutch 60
automatically disconnects and changes to driven mode.

Reference numeral 61 shown in FIGS. 1 and 2 is a clamp moving table that pulls out the workpiece to the exit side. This clamp moving table 61 is movably guided by a pair of guide rails 63 provided on a pedestal 62 on the floor 15 on the outlet side of the welding machine 16, and is driven by a cylinder 64 fixed to the pedestal 62. be done. A clamp unit 66 of a link mechanism that is opened and closed by a cylinder 65 is provided on the clamp moving table 61.

A support stand 67 on the work output side is fixed on the pedestal 62, and this support stand 67 is provided with a plurality of rollers 68 for moving the welded workpiece. Then, with the clamp unit 66 clamping and holding the tip of the workpiece, the clamp moving table 61 moves forward on the guide rail 63 by the operation of the cylinder 64, and pulls the workpiece on the rollers 68 in synchronization with the drive of the electrodes 17 and 18. . Furthermore, when the end of the workpiece passes under an optical sensor (not shown) provided at a predetermined position on the exit side, this is detected and the clamp moving table 61 is stopped.6 Next, the operation of this embodiment is as follows. Explain.

First, place the workpieces 1 and 2 to be welded at a predetermined position on the entrance side conveyor 20 and press the start button. When the start button is pressed, the drive source 22 of the conveyor 20 is activated, and the rollers 21 of the conveyor 20 and Lower roller 5 of clamp roller 51
7 and each rotation starts at the same time. conveyor 20
The stopper 46 advances simultaneously with the rotation of the electrodes 17 and 18.
protrudes into the planes on both sides of the electrode pressurizing point, that is, into the conveying plane. When the works 1 and 2 move forward on the conveyor 20 and come into contact with the stopper 46, a sensor provided on the stopper 46 detects this, and this detection signal causes the moving stage provided on the pulling drive device 25 to move. 28 and 29 are moved by the operation of cylinders 32 and 33, and the cam roller 36 pushes the edges of the work from both sides, and the work 1,
2 is brought close to each other, and an overlap of several millimeters is formed against the Z bar 37 of the seam joint setting layer.

At this time, the clamp unit 66 provided on the clamp moving table 61 clamps the two workpieces 1°2 at the same time at the standby position.

Next, the upper electrode 17 and the upper roller 5 of the clamp roller 51
2 simultaneously pressurizes the works 1 and 2 and clamps them so that the overlapping margin of the seam weld line does not shift.

At this time, the clutch 60 of the lower roller 57 of the clamp roller 51 is disengaged, and the lower roller 57 of the clamp roller 51 is switched from being driven to being driven.

At the same time, the stoppers 46, 47 are pulled upward by the actuation of the cylinder 50 and are retracted from the conveying surface.

When the stoppers 46 and 47 are retracted from the conveying surface, the electrodes 17.
18 starts rotating, and at the same time, the clamp moving table 61 moves forward in synchronization with the rotation of the electrodes 17 and 18 to pull the works 1 and 2. At this time, a welding current is simultaneously applied between the electrodes 17 and 18, and continuous welding begins. When the welding is finished, the ends of the works 1 and 2 are detected, the current supply is stopped, and the clamp roller 32 is opened at the same time as the electrodes are opened. And work 1, 2
is pulled as it is, sufficiently away from the electrode position, and the clamp unit 66 of the clamp moving table 61 moves to the workpieces 1 and 2.
When the cylinder 64 reaches a position where it can be inserted into the rear end side, a sensor detects this and drives the clamp moving table 61.
stop. This cylinder 64 can freely stop its stroke depending on the length of the works 1 and 2. When the clamp moving table 61 stops, the clamp is released, the clamp moving table 61 returns to its original position, and the stopper 46 moves forward to complete one cycle. Thereafter, preparations are made for the next operation in the same manner.

According to this embodiment, by simply placing the workpiece 1.4 to be welded on the conveyor 20, the process starts from positioning the overlap margin of the seam weld joint to automatically feeding the workpiece to the welding position.
These series of welding processes can be performed fully automatically, including automatic workpiece unloading. Therefore, compared to conventional equipment, a large-scale lamp is not required, the entire equipment can be simplified, and the production tact time can be significantly shortened, thereby reducing costs.

Although the above embodiment has been described in the case where the welding machine 16 is a seam welding machine, the welding machine may be another resistance welding machine, for example, a spot welding machine. Further, the structure of each part of the automatic resistance welding machine shown in this embodiment may be other structures without departing from the gist of the present invention.

〔Effect of the invention〕

As described above, according to the present invention, simply by placing the workpieces to be welded on the conveyor, a series of operations such as positioning the overlap margin of the seam weld joint, automatically feeding the workpieces to the welding position, and automatically carrying out the workpieces is performed. The welding process can be carried out fully automatically, and therefore the production tact can be significantly shortened and costs can be reduced by using an automatic resistance welding device with a simple structure.

[Brief explanation of the drawing]

FIG. 1 is a plan view showing an embodiment of an automatic resistance welding machine according to the present invention, FIG. 2 is a front view of FIG. 1, and FIG. 3 is a plan view showing the width shifting drive means of FIG. 1. 4 is a front view of FIG. 3, FIG. 5 is an enlarged view of the main part of FIG. 4, and FIG. 6 is a front view of the stopper of FIG. 2. 7 is a view taken along line B-B in FIG. 6, FIG. 8 is an enlarged plan view of the main part of FIG. 6, FIG. 9 is a side view showing the clamp roller in FIG. 2, and FIG. 9 is a front view, FIG. 11 is a front view showing the upper and lower stoppers of the Z bar in FIG. 3, FIG. 12 is a plan view showing an example of a pair of workpieces to be welded, and FIG.
14 is a plan view showing a conventional seam welding machine, and FIG. 15 is a side view of FIG. 14. FIG. 16 is a front view of FIG. 14. 1.2...Work, 16...Welding machine, 17
, 18... Upper and lower electrodes, 20... Conveyor, 2
5... Driving means for width adjustment, 37... 2 bars. 42... Stopper, 51... Clamp roller. 61...Clamp moving table.

Claims (1)

[Claims] (1) In an automatic resistance welding device that performs resistance welding by placing the end surfaces of a pair of workpieces facing each other and overlapping them by a certain width, a conveyor is used to place the pair of workpieces and transport them parallel to the welding end surfaces to the welding position. , a stopper for stopping the conveyance of the workpiece at the welding position; a driving means for overlapping the welding end surfaces of the workpieces stopped by the stopper by a certain width; and opening and closing near the welding end surfaces of the workpieces overlapped by the constant width. An automatic resistance welding device comprising: a pair of upper and lower clamp rollers that freely clamp the work; and a clamp moving table that moves the work clamped by the clamp rollers into and out of a welding machine.