JP2000202628A - Welding equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the welding equipment that a water cooled torch having different rated current can be used and is not burned. SOLUTION: A pressure switch 2 to close a contact in the case of a water pressure of 0.7 kgf/cm2 and a flow rate detector 40 to close a contact in the case of a flow rate of >=0.6 l/min are arranged to a piping 5 through which cooling water flows. The contacts of the pressure switch 2 and the flow rate detector 40 are in series connected to the contact of a welding start switch. By this method, the water cooled torch having different rated currents can be used, further, the water cooled torch is not burned.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a welding device provided with a water pressure detecting device in a flow path of a cooling water so that a water-cooled torch (hereinafter referred to as a water-cooled torch) can be used.

[0002]

2. Description of the Related Art A water-cooled torch is used for welding with a large current or continuous welding for a long time. Such a welding device will be described with reference to the drawings. FIG. 3 is a connection system diagram of a conventional welding device using a water-cooled torch, and FIG.
FIG. 4 is a connection diagram of a welding start switch. In the figure, reference numeral 1 denotes a welding device. Reference numeral 2 denotes a pressure switch, which is arranged in the middle of a pipe 5 connecting the cooling water inlet terminal 3 and the cooling water supply terminal 4, and as shown in FIG. 4, a contact 3a is connected in series with a contact 6 of a welding start switch (not shown). It is connected to the. 7 is a pipe,
The cooling water return port 8 and the cooling water outlet terminal 9 are connected.

A cooling water device 10 includes a pump, a tank, and a cooling device (not shown). A discharge port 13 is connected to the cooling water inlet terminal 3 through piping 11 and 12, and a return port 14 is connected to the cooling water outlet terminal 9. Connected to each other.

[0004] Reference numeral 20 denotes a water-cooled torch.
Is connected to the cooling water supply terminal 4, and the cooling outlet terminal 22 is connected to the cooling water return port 8.

In FIG. 3, reference numeral 30 denotes an air-cooling / water-cooling switch, which selects the air-cooling side when using an air-cooled torch and the water-cooling side when using a water-cooled torch.

Next, the operation of the above-described conventional welding apparatus will be described. Prior to welding, the cooling water device 10 is operated by setting the air / water cooling switch 30 to the water cooling side. Then, the cooling water is discharged 13 → cooling water inlet terminal 3 → pipe 5 → cooling water supply terminal 4 → cooling water inlet terminal 21 → cooling outlet terminal 22
The cooling water circulates through a route of a cooling water return port 8 → a pipe 7 → a cooling water outlet terminal 9 → a cooling water return port 14. If the water pressure exceeds a predetermined value, the contact 3a is closed, so that welding can be performed by turning on the welding start switch, that is, closing the contact 6, and the tip of the water-cooled torch 20 can be cooled.

[0007]

For example, in the case of a water-cooled torch for TIG welding, the length of a torch cable including a hose for cooling water is about 10 m. Since the welding work site is not always flat, the torch cable may be bent in the middle and the cooling water may not flow. Even in such a case, since the contact 3a is closed, when the contact 6 is closed, welding is started and the water-cooled torch may be burned. Also, when the inside of the hose is clogged with dirt or scale, and the flow of the cooling water is deteriorated, the water-cooled torch may be burned.

If the flow rate detecting device is arranged in the pipe 5 instead of the pressure switch 2, the above-mentioned problem does not occur, but there are the following problems. That is, usually, the rated use rate of the welding device is about 60% in a cycle of 10 minutes, and the rated use rate of the water-cooled torch is 80 to 100%.
Therefore, continuous welding with a welding current of 300 A (use rate 100
%), The rated current of the welding equipment is 5
00A must be used. On the other hand, the water-cooled torch may have a usage rate of 100% and a rated current of 300 A, and is lighter in weight than a water-cooled torch with a rated current of 500 A, so that workability is good.

However, since the operability of the welding torch is emphasized, the inner diameter of the hose is made thick enough to allow a necessary amount of water to flow. On the other hand, in the case of a welding device with a rated current of 500 A, the flow rate is set according to a water-cooled torch with a rated current of 500 A. For this reason, when a water-cooled torch with a rated current of 300 A is connected to a welding device with a rated current of 500 A, the flow detecting device does not turn on because the amount of cooling water flowing inside is less than the flow rate set in the flow detecting device. Can not.

An object of the present invention is to solve the above-mentioned problems in the prior art and to provide a welding apparatus which can use water-cooled torches having different rated currents and does not burn the water-cooled torch.

[0011]

In order to achieve the above object, the present invention relates to a welding apparatus provided with a water pressure detecting device in a flow path of a cooling water so that a water-cooled torch can be used. A flow detection device is provided, and the flow detection device is disposed in the flow path, and a contact between the water pressure detection device and the flow detection device is connected in series to a welding start switch.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the illustrated embodiments. FIG. 1 is a connection system diagram of a welding device using a water-cooled torch according to the present invention, and FIG. 2 is a connection diagram of a welding start switch. Description is omitted. In the figure, 40
Is a flow rate detecting device, which is arranged in series with the pressure switch 2 in the pipe 5. The contact 40a is connected in series with the contact 3a and the contact 6. Here, pressure switch 2
Operating pressure of 0.7 kgf /
cm ² . The flow rate detection device 40 is a contact 40a when a water-cooled torch with a small rated current, for example, 0.6 l / min or more required by a water-cooled torch with a rated current of 200A.
Is to close.

Next, the operation of this embodiment will be described. Prior to welding, the cooling water device 10 is operated by setting the air / water cooling switch 30 to the water cooling side. Then, the cooling water is discharged 13 → cooling water inlet terminal 3 → pipe 5 → flow rate detecting device 40 → cooling water supply terminal 4 → cooling water inlet terminal 21 → cooling outlet terminal 22 → cooling water return port 8 → pipe 7 → It circulates in the route from the cooling water outlet terminal 9 to the cooling water return port 14. The water pressure is 0.7 kgf / cm ² and the flow rate of cooling water is 0.6 l /
When the length is equal to or more than min, both the contact 3a and the contact 40a are closed, so that welding can be performed by closing the contact 6.

In this embodiment, the flow rate detected by the flow rate detection device 40 is adjusted to a water-cooled torch with a rated current of 200 A.
For example, a water-cooled torch with a rated current of 500 A can also be used.

Incidentally, the flow rate detecting device 40 may be arranged in the pipe 7.

[0016]

As described above, according to the present invention,
In a welding device provided with a water pressure detecting device in a cooling water flow path, a water cooling torch can be used, a flow rate detecting device is provided, and the flow rate detecting device is arranged in the cooling water flow path, and Since the contacts are connected in series to the welding start switch, the welding start switch does not operate when dust or the like is clogged in the inside of the hose or the amount of cooling water is less than a preset flow rate. As a result, welding is not performed, and burning of the water-cooled torch can be prevented.

[Brief description of the drawings]

FIG. 1 is a connection system diagram of a welding device using a water-cooled torch according to the present invention.

FIG. 2 is a connection diagram of a welding start switch according to the present invention.

FIG. 3 is a connection system diagram of a conventional welding device using a water-cooled torch.

FIG. 4 is a connection diagram of a conventional welding start switch.

[Explanation of symbols]

 2 Pressure switch 5 Piping 40 Flow rate detector

Claims (1)

[Claims] 1. A welding apparatus provided with a water pressure detecting device in a flow path of a cooling water so that a water-cooled torch can be used, a flow rate detecting device for a cooling water is provided, and the flow rate detecting device is arranged in the flow path. A contact point between the water pressure detecting device and the flow rate detecting device is connected in series to a welding start switch.