JPH06227Y2 - Chip cooling device for spot welding gun - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to a tip cooling device for cooling the tip of a spot welding machine.

(Prior Art) In a conventional chip cooling device, a drain hole 102 is formed in a chip 100 and a shank 101 as shown in FIG. 4, and a water supply pipe 103 is installed in the hole, and a certain constant pressure is applied. Cooling water is supplied to the tip 100 via the water supply pipe 103, the cooling water heated by the tip 100 is guided to the drain pipe via the drain hole 102, and the drain pipe of each welding machine is integrated. It is known that cooling water is discharged from a drain pipe, cooled in a cooling tower and returned to a circulation tank.

(Problems to be solved by the invention) In recent years, galvanized steel sheets have been frequently used for steel sheets forming automobile bodies in order to enhance the rust prevention effect.

However, when performing spot welding, it is necessary to increase the electric current and perform welding as compared with the conventional cold-rolled steel sheet. Therefore, the tip generates more heat than before, and in the tip cooling device described in the prior art, because the cooling effect is low, welding occurs between the tip and the work, and as a result, the tip comes off from the shank and the welding work must be stopped. It had a problem that it did not become.

There is also a method of increasing the pressure of the cooling water supply pump to increase the amount of water supply, but it is said that it is against energy saving if welding work of galvanized steel sheet is only performed in part of the spot welding process. I had a problem.

The present invention has been made in view of the above problems of the prior art, and an object of the present invention is to enhance the cooling effect of the tip and to contribute to energy saving as well as the tip cooling of the spot welding machine. It is intended to provide a device.

(Means for Solving the Problems) In order to solve the above problems, the present invention forms a bypass drainage pipe communicating from a shank to the drainage pipe and provides a pump on the bypass drainage pipe.

Also, a pressure switch may be provided in the air circuit of the spot welding gun so that the pump operates when the gun is pressurized.

(Operation) Most of the cooling water heated by the chips heated by energization is forcibly discharged through the bypass drain pipe by the operation of the pump.

Moreover, the pump can be operated only when the gun is pressurized including the energization time.

(Embodiment) An embodiment of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is a sectional view of an essential part of an embodiment of the present invention, and FIG. 2 is a configuration explanatory view of the same.

As shown in FIG. 2, the spot welding gun 1 connects substantially symmetrical arms 2 and 2 with a pin 3, and an air cylinder 4 provided at a rear end of the arms 2 and 2 advances and retreats to interpose the pin 3 therebetween. The arms 2 and 2 swing so that the tips 6 and 6 fitted to the tips of the arms 2 and 2 via the shanks 5 and 5 come into contact with each other at a predetermined pressure.

Then, as shown in FIG. 1, a water supply pipe 8 for cooling the tip is provided in a drain hole 7 formed inside the shank 5 and the tip 6.
Is decorated. The drain hole 7 is connected to a drain pipe 10 that communicates with a cooling tower (not shown) via drain passages 9 formed in the arms 2 and 2. The water supply pipe 8 also has water supply passages 11 and 1 formed in the arms 2 and 2.
1 is connected to a water supply pipe 12 leading to a circulation tank (not shown).

Further, bypass drain pipes 13, 1 are provided on the sides of the shanks 5, 5.
3 is connected so as to communicate with the drain hole 7, and is connected to the drain pipe 10 via the pump 14 together with the drain pipe 15 connected from the drain passages 9 in the arms 2 and 2.

FIG. 3 is a diagram showing an air circuit for causing the spot welding gun 1 to perform a pressurizing operation, in which the switching valve 22 is connected to the air source 20 via the regulator 21, and the switching valve 2 is further connected.
The air circuit 23 connects the pressure switch 24 to the air cylinder 4.

The operation of the tip cooling device for the spot welding gun configured as described above will be described below.

The switching valve 22 is actuated in response to a welding command, and air of a predetermined pressure is supplied from the air source 20 via the air circuit 23 to turn on the pressure switch 24, and further the air cylinder 4 is extended to weld the members to be welded between the tips 6 and 6. Sandwich, pressurize, energize and heat.
Then, the pump 14 is activated by the pressure switch 24 that is turned on simultaneously with the pressurization of the gun 1, and the heated cooling water passes through the bypass drain pipes 13 and 13 and the conventional drain passages 9 and reaches the drain pipe 10. Be guided.

Then, the switching valve 22 is switched by the welding end signal, the air cylinder 4 is retracted, and at the same time, the pressure switch 24 is turned off and the pump 14 is stopped.

(Effect of the Invention) As described above, according to the present invention, since the bypass drainage pipe is formed and the pump is provided in the bypass drainage pipe, the cooling efficiency is improved and the chip welding can be prevented.

Further, since the pump is operated only when pressurizing by the pressure switch, it is possible to contribute to energy saving.

Further, even if the spot welding work of the galvanized steel plate is mixed in the spot welding work process of the cold rolled steel plate, it can be individually and easily dealt with.

[Brief description of drawings]

FIG. 1 is a sectional view of an essential part of an embodiment of the present invention, FIG. 2 is a configuration explanatory view of the same, FIG. 3 is an air circuit diagram, and FIG. 4 is a sectional view of an essential part showing a conventional example. In the drawings, 1 is a spot welder, 5 is a shank, 6 is a tip, 10 is a drain pipe, 13 is a bypass drain pipe, 14 is a pump, 23 is an air circuit, and 24 is a pressure switch.

Claims (2)

[Scope of utility model registration request] 1. A spot cooling apparatus for cooling a tip of a spot welding machine by water supply and drainage, characterized in that a bypass drain pipe communicating from a shank to a drain pipe is formed and a pump is provided in the bypass drain pipe. Gun tip cooling device. 2. The tip cooling device for a spot welding gun according to claim 1, wherein the pump is provided with a pressure switch in the air circuit of the spot welding gun so as to operate when the gun is pressurized.