JPS5836460Y2 - Resistance welding machine electrode dressing device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION This invention relates to a device that can automatically dress the electrodes of a resistance welding machine.

Generally, the tip end of a cap tip used as an electrode in a resistance welding machine is worn out and loses its shape with use, so it is necessary to correct this by dressing each time it is used a predetermined number of times.

For this reason, dressing has conventionally been performed using a hand dresser or a lathe.

However, in welding machines such as multi-welding machines that have a large number of electrodes arranged in a narrow space, complex holding jigs for the workpiece, cooling water pipes, compressed air pipes, cables, etc. are arranged around the electrodes. Therefore, dressing using a hand dresser is not only difficult to work with, but also has problems such as chips entering the welding machine.

In addition, in the method using a lathe, a large number of cap chips must be dressed one by one by humans.
There is a problem of poor work efficiency.

In response to this, devices have been proposed that automatically dress cap chips.

However, since this type of device is based on the premise of uniformly dressing cap tips with the same degree of wear, each cap tip has a different number of uses, and therefore it is preferable to use multiple cap tips with different degrees of wear and length. The disadvantage is that it cannot be used as a dressing and is not practical.

This idea was developed in view of the above. After the dressing tool comes into contact with the cap chip, the dressing tool is attached to a spindle that can reciprocate with respect to the cap chip set on the index table. It is an object of the present invention to provide a dressing device which can automatically dress cap chips having different degrees of wear and length by a uniform amount.

This invention will be explained below based on the drawings.

FIG. 1 shows an embodiment of this invention. In the figure, 1 is a machine base, 2 is a disk-shaped index table installed horizontally at the base of this machine base 1, and 3 is a disc-shaped index table provided horizontally at the base of this machine base 1. This is a tool part for dressing the set cap chip C.

The index table 2 has cap chip supports 4 at positions equally divided in the circumferential direction on its upper surface, and is fed horizontally by a central angle equal to the angle equally divided into the circumference by a link mechanism (not shown). It is designed to be moved.

As shown in FIG. 2, the cap chip holder consists of a conical tube 6 having a center hole 5 that vertically passes through the table 2, and an A-dome type C on the outside of the conical tube 6 as shown in FIG. , B radius type c', c flat type C1/, and various other types of cap chips can be fitted.

The cap chip is fitted into the cap chip support 4 manually or by a robot, and after the dressing described below is performed, an air cylinder installed below one side of the inch table 2 is used. The knockout pins 8 of 7 are inserted through the center hole 5 in one direction, and are taken out through a chute 9.

On the other hand, the tool section 3 has a built-in air cylinder 10 that allows it to expand and contract in the vertical direction.
A spindle 13 is provided which can rotate by connecting a belt 12 to a motor 11 installed in parallel with the motor 11, and a dressing tool 14 is fixed to the lower end of the spindle 13 for directly contacting and grinding the cap chip C. .

As shown in FIG. 4, the air cylinder 10 is connected to an air source 17 via a valve device 16 that is opened/closed or activated by a control circuit 15, and the spindle 13 is controlled by the valve device 16. The vertical movement of the tool 14, particularly the speed and amount of vertical movement, are controlled.

The control circuit 15 also includes a sensor 18 that extracts the load applied to the motor 11 as electric power, a converter 19 that converts this output into voltage, an amplifier 20 that amplifies the output voltage of this converter 19, and a low frequency Circuit for removing noise 21. Memory for storing reference power in advance and comparing the difference between this and load power with set power, comparison circuit 22, and timer circuit 2
It has 3.

In FIG. 1, reference numeral 24 denotes a clamp driven by an air actuator 25, which grips the cap tip during dressing.

According to the above configuration, the cap chips C are fitted into the cap chip supports 4 on the index table 2 manually by a worker or by an automatic machine such as a robot. ... are sequentially moved to a position below the tool section 3 as the index table 2 rotates intermittently.

Then, in this position, it is held by the clamp 24,
be kept in a fixed state.

Then, the motor 11 in the tool section 3 rotates to rotate the tool 14, and the air cylinder 10 operates to move the tool 14 downward, and the cap chip C is dressed by these two operations.

At this time, the tool 14 moves downward and comes into contact with the upper surface of the cap chip C, and when dressing is performed from now on,
The load on the tool 14 increases, and the sensor 18 detects this increase in load as an increase in power.

This detection signal is transmitted to a converter 19, an amplifier 20, a low frequency noise removal circuit 21. The data is transmitted to the comparator circuit 22, where the timer 23 is activated based on a preset date.

Since the timer 23 functions to keep the valve device 16 open only during the operating time, air from the air source 17 is supplied to the air cylinder 10 during this time, and the tool 14 is moved downward for dressing.

Then, when a predetermined period of time has elapsed, the valve device 16 closes,
The air cylinder 10 moves the tool 14 upward to complete the dressing.

Due to this action, each cap chip C......
Even if there are differences in their lengths, they will be uniformly dressed by a certain dimension from the top surface before dressing.

Of course, the amount of dressing is determined by the set time of the timer 23.

Furthermore, as shown in FIG. 3, when cap tips of different shapes are used, the amount of dressing, that is, the set time is different.

The cap tip is rotated to a position above the knockout pin 8 where dressing has been completed, and taken out into the shoe 1-9 by the knockout pin 8.

The cap chip C is moved within the chute 9 and taken out as shown by the chain line in FIG.

It goes without saying that when dressing cap chips of different shapes, the shape of the tool is changed to suit each shape.

As explained above, the dressing device of this invention is configured so that after the dressing tool comes into contact with the cap tip and starts the dressing action, the dressing action is performed only for a predetermined time. Different cap tips can be automatically dressed in a uniform amount, and this has great practical effects such as improving work efficiency and reducing labor.

[Brief explanation of drawings]

FIG. 1 is an overall side view of the dressing device according to this invention, FIG. 2 is a partially enlarged view, FIGS. 3A to 3C are side views of different examples of cap tips, and FIG. 4 is a control circuit diagram. 2... Index table, 3...
・Tool part, 10... Air cylinder, 11...
... Motor, 14 ... Dressing tool, 15 ... Control circuit, 16 ... Valve device, 18 ... Sensor, 22 ... ...Comparison circuit, 23...Timer circuit, C...Cap chip.

Claims (1)

[Scope of utility model registration request] Fits and supports the cap chip that becomes the electrode of the resistance welding machine,
and an index table for sequentially moving the plurality of cap chips to a dressing position; and a dressing tool that can be reciprocated by an air cylinder or the like and that dresses the cap chips during this reciprocating movement. and a timer and a circuit for detecting the contact in the control circuit of the air cylinder etc. so that the dressing tool can perform the dressing action while moving for a predetermined period of time from the time the dressing tool contacts the cap chip. A dressing device for an electrode of a resistance welding machine, characterized in that it is equipped with a circuit, etc.