JPS5817714B2 - Electrode surface dressing device for resistance welding machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a dressing device l for shaping and modifying the electrode surface of a resistance welding machine.

Generally speaking, projection welding is a type of resistance welding.
For example, as shown in Fig. 1, a ring-shaped protrusion is formed on one of a pair of objects to be welded 1 and 2, and welding is performed by applying pressure and current using upper and lower electrodes 3 and 4. In this method, it is particularly important to maintain the surface condition of the opposing surfaces (electrode surfaces) of the electrodes 3 and 4 in a predetermined ideal state f from the viewpoint of quality stability.

However, when the object to be welded is a surface-treated steel plate,
The electrodes 3 and 4 made of copper or copper alloys are alloyed with the surface material of the workpiece on the electrode surface to form an impurity layer, and when this layer becomes thick to a certain extent, electrical resistance increases and one welding defect occurs. On the one hand, this will lead to a decline in quality, and on the other hand, if abnormal generation occurs, the life of the rising electrode will be significantly shortened.

In particular, if the electrode surface is burnt out and its flatness is impaired, it becomes difficult to achieve uniform pressing force and uniform current distribution on the object to be welded.

For this reason, the electrode surface has traditionally been regularly dressed (cutting or grinding) to remove the impurity layer and repair the burnt part, but the general dressing process is to remove the electrode once (with the force of a welding machine). Because the workpiece is removed and then cut or ground using a machine tool, the workpiece is surrounded by a complex holding jig, etc., and is tightly tightened with several bolts, etc. like the lower electrode. It is extremely difficult to remove and reinstall electrodes from the welding machine, and there are cases where the electrodes are missing and require a lot of time.

For example, in the projection method for welding workpieces 1' and 2' as shown in Fig. 2, the most effective means at present is to use a split-shaped lower electrode 41 for operational reasons. When modifying the lower electrode, it is extremely difficult to grind the left and right electrodes, the electrodes of the electrodes 4a and 4b, and the electrode surfaces of the electrodes 4a and 4b flat and add more layers.

The present invention has been developed in view of the above, and its main feature is that the distal end E of the rotating arm is provided in the reciprocating part between the upper and lower electrodes of the resistance welding machine.

By adding tools for dressing at least one electrode surface of the lower electrode and by providing the arm with vertical position adjustment and automatic rotational feeding, the electrode can be easily removed without adding or removing the upper and lower electrodes. It is an object of the present invention to provide a dressing device that can perform accurate dressing of a surface and thus simplify the dressing operation.

Hereinafter, the present invention will be explained with reference to Embodiment 1 shown in FIGS. 3 and 4.

FIG. 3 is an overall view of a resistance welding machine equipped with the dressing device of the present invention, where 5 is the resistance welding machine main body, 3 and 4 are the upper electrode and lower electrode equipped on the welding machine main body frame 6, and in particular, When not welding, the upper electrode 3 is in the upper position as shown in the figure, and when welding, it moves downward so as to sandwich the workpiece between it and the lower electrode 4.

Reference numeral 1 denotes a dressing device integrally attached to the frame 6, and particularly includes a tool 8 provided at the tip of the lower end for dressing the electrode surfaces of the upper and lower electrodes 3 and 4 by grinding, cutting, etc. .

That is, as shown in the details of the dressing device in FIG. 4, a bracket 9 is attached to the resistance welding machine frame 6, and a hollow seven strokes 10 are supported thereon so as to be movable up and down.

A motor 11 is fixed to the upper end of the mast 10, and a rotating shaft 12 integral with the rotating shaft 11a extends within the seven-stroke shaft 10 and rotates a sprocket 13 provided at the lower end.

14 is an arm attached horizontally to the lower end of the 7-stroke 10,
At its tip, an idling shaft 16 integral with the sprocket 15 is fixed, and is driven to rotate by a chain 17E wound around the sprocket 15.

In addition, the upper end and/or lower end of this idle shaft 16 is ground.
A cutting tool 8 is added.

Further, at a position near the upper end of the seven masts 10, a connecting arm 18 is protruded from the side, and a threaded rod 1 parallel to the mast 10 is connected to the connecting arm 18.
9 is suspended vertically.

A worm wheel 20 supported by the bracket 9 is screwed onto this threaded rod 19, and a worm 22 integrated with a micro index bundle 21 is attached to the worm wheel 20.
are screwed together.

In addition, the micro index bundle 21 is a manual t4M'r.
However, an electric motor may be used instead.

On the other hand, an actuator 23 that reciprocates in a direction perpendicular to the plane of the paper using hydraulic or pneumatic pressure is installed inside the bracket 9, and a rack 2 is formed on one side of the actuator 23.
The ring gear 25 that meshes with the 7th stroke 10 can rotate around the 7th stroke 10.

A ring-shaped engagement member 26 faces the ring gear 25.
is connected to the 7 stroke 10 with a key 27 in the axial direction.

It is moved upward by air pressure or the like introduced into a chamber 28 defined between the bracket 9 and the ring gear 25 and the clutch 29 are engaged with each other.

Note that the engaging member 26 may be configured to be moved up and down manually using a band lever or the like.

According to this configuration, while the resistance welding machine 5 is in operation, the dressing device is in a state where the electric tool 8 is retracted from between the upper and lower electrodes 3 and 4 as shown by the imaginary line in FIG.
If dressing No. 4 is required, first manually rotate the No. 7 stroke 10 and the arm 14 horizontally, and then remove the tool 8.
Rub it so that it is approximately located between the upper and lower electrodes 3 and 4 as shown by the solid line in FIG.

By driving the motor 11, the rotational force of the rotating shaft 12 is transferred from the rotating shaft 12 to the sprocket 13.
, is transmitted to the tool 8 via the chain 11, sprocket 15 and idle shaft 16, and rotates the tool 8 to make it ready for dressing.

Next, by manually operating the micro index bundle 21 and rotating the worm 22, the worm wheel 20 rotates, and the threaded rod 19 that is threaded thereon moves up or down to move the mast 10 up or down, The amount of upward or downward movement of the tool 8 is determined by the amount of rotation of the bundle that brings the tool 8 into contact with the electrode surface to perform dressing, thereby setting the amount of dressing.

Further, by introducing air pressure into the chamber 28, the engaging member 26 is moved upward and clutch-engaged with the ring gear 25, so that the two are integrated, and then the actuator 23 is driven to rotate the ring gear 25. , engagement member 26
and the seventh stroke 10 rotates to cause the arm 14, that is, the tool 8, to move in an arc.

This makes it possible to feed the electrode during dressing, thereby uniformly dressing the electrode surface.

After finishing the dressing, the tool 8 is retracted from between the upper and lower electrodes 3 and 4 by the reverse operation, but since the ring gear 25 and the engagement member 26 are normally in a disconnected state, The arm 14 can be quickly stored (returned) to any position 1.

In this case, the stroke of the actuator 23 is made longer, the 7th stroke 10 is rotated fully automatically, and the tool 8 is rotated fully automatically.
It is also possible to automatically move Eζ between the inter-electrode position and the retracted position.

Furthermore, if the tool 8 is provided on both the upper and lower sides and the upper electrode 3 is moved downward by one inch during dressing, the lower electrode 3
, 4 at the same time, and the working time can be further reduced.

As described above, according to the dressing device of the present invention, since the resistance welding machine is integrally attached, there is no need to install the dressing device, which is effective in reducing space, and it is also effective for reducing electrode dressing. Since the tool is retracted during welding and inserted between the electrodes when not welding (dressing), it is possible to dress the electrode surface without removing the upper and lower electrodes from the welding machine. This has the advantage that the number of man-hours required for dressing can be greatly reduced.

Especially when the workpiece to be welded is a surface-treated steel plate with severe damage to the E-column surface, or the lower electrode is a split mold as mentioned above, the conventional work man-hours are more effective. is remarkable.

History 11 According to the present invention, it is possible to provide a dressing device using a conventional resistance welding machine almost as is.

In addition, by vertically adjusting the arm with the tool attached, it is possible to set the amount of dressing, and the arm can be automatically rotated. The tool moves while rotating, significantly improving the accuracy of finishing the electrode surface flat.Furthermore, by moving the tool over the electrode surface, chips are removed, making dressing the electrode surface faster (and more efficient). It also has the effect that it can be performed with a precision of 1.

[Brief explanation of the drawing]

1 and 2 are side sectional views and HA'FM diagrams for explaining projection welding, FIG. 3 is an overall front view of a resistance welding machine equipped with the device of the present invention, and FIG. 4 is a diagram of the device of the present invention. It is a partially cutaway front view. 5...Resistance welding machine body, 7...Dressing device, 8...Tool, 10...
Mast, 11...Motor, 12...Rotating shaft, 13.15...Sprocket, 1
7...Chain, 19...Threaded rod, 2
0... Worm wheel, 22... Worm, 23... Actuator rod, 24
······rack. 25...Ring gear, 26...Engaging member, 27...Key, 29...Clutch.

Claims (1)

[Claims] 1 Attach a tool for dressing at least one electrode surface of the upper and lower electrodes to the tip of a rotating arm whose tip is movable between the upper and lower electrodes of the resistance welding machine, and Electrode surface dressing device 32 for a resistance welding machine, characterized in that the upper and lower positions can be adjusted and the electrode surface can be automatically rotated and fed. An electrode surface dressing device for a resistance welding machine according to claim 1.