JPH01202376A - Arc machine - Google Patents

Abstract

PURPOSE:To prevent a water leak at the time of attaching or detaching operation of a changing part by providing a cooling water-gas substituting mechanism to substitute gas for the circuit inside for cooling water before attaching or detaching operation of the changing part to a water supplying and draining mechanism for cooling. CONSTITUTION:A solenoid valve 16 is operated to communicate a pipe 14 with a pipe 15 and a pump 17 is operated before or after this operation. By this method, the air is flowed in the pump 17 via the pipes 14 and 15. The air compressed by the pump 17 is discharged to the pipe 18 side and the cooling water in the circuit for cooling water is pressed out by the compressed air. The changing part such as a nozzle 5 or an electrode is attached or detached. By this method, since the cooling water can be drained practically from the circuit inside for cooling water before attaching or detaching operation inside for cooling water before attaching or detaching operation of the changing part which is water-cooled directly by the cooling water-gas substituting mechanism, the water leak at the time of attaching or detaching operation of the changing part which is water-cooled directly can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to an arc machining device for welding or cutting workpieces.

<Prior art> In general, in arc processing equipment, such as plasma arc processing equipment, water cooling is performed as appropriate to prevent the arc processing torch from becoming too hot. To make it longer, replacement parts are directly water cooled.

For example, in FIG. 5, 1 is an electrode support member made of a conductive material, 2 is a hollow electrode supported at the tip of the electrode support member 1, 3 is an insulating sleeve provided outside the electrode support member 1, and 4 is an insulating sleeve provided outside the electrode support member 1. A nozzle support member 5 made of a conductive material and provided outside the insulating sleeve 3 is a hollow nozzle supported at the tip of the nozzle support member 4, and a plasma flow jetting hole 501 is bored in the center of the tip. Reference numeral 6 indicates an insulating cup, and 7 indicates a cooling water guide pipe. The cooling water introduced from the supply hose 8 directly cools the electrode 2, and then flows out of the torch from the drain hose 9 through the passage indicated by the arrow.

Note that an appropriate plasma arc forming fluid G such as compressed air or oxygen is appropriately supplied and ejected from the plasma ejection hole 501.

Conventionally, when using the plasma arc processing torch 10 described above, the cooling water supply source and the supply hose 8 are connected via an on-off valve, and when replacing replacement parts such as the electrode 2 and the nozzle 5, the on-off valve is used. was closed to cut off the cooling water supply.

<Problems to be Solved by the Invention> However, when the directly water-cooled replacement parts as described above are removed, the water remaining inside the torch flows out. If the vicinity of the machining part is wet with water as described above, there is a risk of electric shock during arc machining work. Of course, the presence of water not only accelerates the wear and tear of various parts of the torch when an arc occurs;
Since there are problems such as not being able to perform good arc machining, there is a drawback that water flowing out must be wiped off every time a replacement part is replaced.

Means for Solving the Problems> An arc processing device according to the present invention includes an arc processing torch having a replacement part that is directly cooled by water, and a water supply source connected to a cooling water circulation path of the torch. In the arc machining apparatus equipped with a cooling water supply and drainage mechanism, the cooling water supply and drainage mechanism is equipped with a cooling water-gas exchange mechanism that replaces the inside of the cooling water circulation path with gas before the operation of attaching and detaching the replacement part. Features.

<Example> Hereinafter, the present invention will be explained in detail with reference to illustrated embodiments.

In FIG. 1, reference numeral 10 denotes an arc machining torch having replacement parts that are directly water-cooled, such as a plasma arc machining torch having the structure shown in FIG. 5. in this case,
Among the replacement parts, the electrode 2 and nozzle 5 are directly water-cooled. The cooling water supply hose 8 and the drainage hose 9 of this torch 10 are connected through the inside of the torch 10,
Forms a cooling water circulation path. 11 is a water storage tank for storing cooling water, and the upper space is communicated with the outside air via an on-off valve 12. - 13 is a pipe inserted into the water storage tank 11, for example, 30,000 solenoid valves 16. is connected to. Further, the electromagnetic valve 16 is connected to a pipe 14 that opens to the atmosphere, and a pipe 15 that is switched to communicate with the pipe 13 or 14. Reference numeral 17 denotes a water pump connected to the pipe 15, and this pump is appropriately selected from a pump capable of pumping water and air respectively, such as a gear pump or a vane pump.

A pipe 18 is disposed on the discharge side, that is, the outflow side, of the pump 17 and is connected to the supply hose 8. Reference numeral 19 denotes a pipe connected to the drain hose 9, and the end of this pipe 19 is disposed at the upper part of the water tank 11. It should be noted that a suitable plasma arc forming fluid supply pipe and electric control line are connected to the torch 10, but since they are the same as in the conventional art, a description thereof will be omitted.

In the arc machining apparatus shown in FIG.
operate. That is, the pump 17 is operated in accordance with the working status of the arc machining work, and each part of the torch 10 is forcibly cooled with cooling water. By the way, when removing directly water-cooled replacement parts, such as the nozzle 5 or the electrode 2, from the torch 1O, first operate the solenoid valve 16 so that the pipes 14 and 15 communicate with each other, and then simultaneously with this operation, turn off the pump. 1
7 is activated. This allows atmospheric air to flow into the pump 17 via the pipe 14.15. Since the air compressed by the pump 17 is discharged to the pipe 18 side, the cooling water in the cooling water circulation path is pushed out by the compressed air. As described above, the cooling water is replaced with air in the cooling water circulation path by the pump 17 that pumps water and gas, respectively, and the solenoid valve 16 that switches the flow path to the pump 17 to cooling water or the atmosphere. - An atmospheric displacement mechanism is formed. In this case, tube 14,1
5.18.19 and depending on the respective cross-sectional areas and lengths of the cooling water passages in the torch 10, the capacity of the pump 17, etc., the replacement of the cooling water with compressed air is accomplished in a relatively short time. .

After the cooling water is discharged from the cooling water circulation path, the nozzle 5 and electrode 2 are replaced as appropriate. Note that the cooling passage of the torch 10 has a small diameter and is formed in a complicated shape, so it may be difficult to completely remove the cooling water, but when the nozzle 5 and electrode 2 are removed, For example, even if there is a few drops of water leaking, the small amount of water leaking from the torch 10 and the workpiece will be vaporized by the arc heat generated by the arc prior to machining, so it will hardly have any negative effects in actual arc machining work. It will not affect you.

In addition, if a water amount detector, that is, a water surface height detector is provided in the water storage tank 11, and a filter is provided when the water surface height is below a predetermined value, clogging in the cooling water circulation path can be prevented. .

As described above, with the arc machining device shown in Fig. 1, not only can the cooling water be automatically circulated, but also the cooling water circulation path can be changed by simply switching the solenoid valve before replacing replacement parts that are directly water-cooled. Since the cooling water inside can be substantially drained, there is no risk of a large amount of water leaking when replacing replacement parts, unlike in the conventional case. That is, leakage of cooling water can be prevented.

FIG. 2 is a diagram showing another embodiment of the present invention, 17
is a pump normally used for water supply, and the discharge side pipe 181 of this pump 17 is connected to, for example, a two-way solenoid valve 16.
1 to the tube 18. 20 is a pressure gas supply source, for example a near compressor, and a pipe 21 on the outflow side
is connected to the pipe 18 via, for example, a two-way solenoid valve 162.

During normal arc machining work, the solenoid valves 161 and 162 are operated so that the pipes 181 and 18 communicate with each other and the pipes 18 and 21 are cut off, and the pump 17 is turned on depending on the work status of the arc machining work. When the torch is operated, each part of the torch 10 is forcibly cooled with cooling water.

By the way, when removing a replacement part that is directly water-cooled from the torch 10, first the pipes 181 and 18 are sharpened. As a result, the cooling water in the cooling water passages 18, 8, 9, 19 is gradually pushed out by the compressed air.

As described above, the solenoid valves 161 and 162 and the pressure gas supply source 20 form a cooling water-pressure gas exchange mechanism that replaces the cooling water with pressure gas in the cooling water circulation path.

After the cooling water has been substantially drained from within the cooling water circuit,
Replace the replacement parts of the torch 10 as appropriate.

In the above, when draining the cooling water, the pump 17 is stopped, but after the pipe 181 is provided with a relief valve and a predetermined pressure is reached, the water in the pipe 181 is pumped outside the pipe 181, for example, into the water storage tank 11. - The operating state of the pump 17 can be set arbitrarily as long as the pump 17 is turned off. Note that only one solenoid valve 161[deg.] 62 is required if a three-way, three-position switching solenoid valve is used.

The equipment shown in Figure 2 has a shorter cooling water circulation path for replacing cooling water with gas than the equipment shown in Figure 1, so it takes longer to replace the cooling water with gas, and it takes longer to cool the water again. Since the time required to fill the water circulation path with cooling water is short,
The waiting time until a state suitable for replacement of a replacement part that is directly water-cooled and the time required to restart the cooling device after replacement are short.

In addition, in FIG. 2, tap water can be used instead of the pump 17. In this case, drain hose 9. tube 19
The wastewater will be disposed of outside the equipment without being reused.

FIG. 3 is a diagram showing still another embodiment of the present invention,
It is suitable for using pressurized gas such as CO2, O2 or compressed air as an arc machining device.

Components with the same functions as those in FIG. 2 are given the same reference numerals.

Reference numeral 22 denotes a pipe for supplying pressurized gas flowing out from the tip of the torch through the interior of the torch 10, and for example, a gas for forming a plasma arc in a plasma arc processing apparatus, illustratively O2, flows therethrough.

163 is a three-way, three-position switching solenoid valve, and the pipe 21, pipe 22, and pipe 18 on the outflow side of the O2 supply source 2° are connected.

During normal arc machining work, the solenoid valve 161 is operated so that the pipes 181 and 18 communicate with each other.

On the other hand, the solenoid valve 163 is operated appropriately so that the pipes 21 and 22 communicate with each other, or the pipes 18, 21, and 22 are respectively cut off.
is supplied to

By the way, when removing a directly water-cooled replacement part from the torch 10, first operate the solenoid valve 161 so that the pipes 181 and 18 are quickly disconnected, and then operate the solenoid valve 163 so that the pipes 21 and 18 communicate with each other.

As a result, the cooling water in the passage is gradually drained by 02. After the cooling water has been substantially drained from the cooling water circuit in this way, the replacement parts of the torch IO are replaced.

In the particular device shown in Fig. 3, a solenoid valve is normally used when pressurized gas is used for arc machining, but this solenoid valve is a 3-way, 3-position solenoid valve, and the pipe 18 Since the cooling water can be drained by connecting the three-way and three-position electromagnetic squares 163 and switching the electromagnetic valve 161, the number of changed parts required for the cooling water-pressure gas exchange mechanism can be reduced.

Note that various pressure gases are used in arc processing equipment, but when using Ar, Ar and He, etc., Ar
And Art-t-He is expensive and therefore not preferred in practice. However, Go! , 02 or compressed air is practical because it has relatively low friction. Particularly, a plasma arc processing apparatus in which 02 or compressed air is commonly used these days is suitable as the apparatus shown in FIG.

FIG. 4 is a diagram showing another embodiment of the present invention, in which reference numeral 17 denotes a pump that feeds and drains water by rotating in forward and reverse directions.

During normal arc machining work, the pump 17 rotates in the normal direction to forcibly cool each part of the torch 10 with water.

By the way, when the pump 17 is reversed, the cooling water in the passage is discharged, and the atmosphere gradually flows in through the pipe 19. After the cooling water has been substantially drained from the cooling water passage in this manner, the replacement parts of the torch 10 are replaced.

If the device is as shown in FIG. 4, the supply and drainage of cooling water can be selected by rotating the pump in the forward direction or in the reverse direction, so that the device implementation becomes extremely simple.

As described above, the present invention is effective because the torch of a plasma arc machining device becomes particularly high in temperature, but it is of course applicable to any appropriate arc machining device such as a so-called TIG arc, MIG arc, or CO2 arc. Furthermore, by providing a cooling water detector in the cooling water circulation path, it is possible to automatically know that drainage of the circulation path has been completed.

Furthermore, if the nozzle is indirectly cooled, cooling water will not leak even if the nozzle is removed from the torch, but
1518 to 11520, a detection mechanism for detecting the state of attachment and detachment of the nozzle to the torch may be provided, and the cooling water passage may be drained by a detection signal when the nozzle is removed from the torch.

<Effects of the Invention> The arc machining device according to the present invention is capable of substantially draining cooling water from the cooling water circulation path by the cooling water-gas displacement mechanism prior to the installation/detachment of replacement parts that are directly water-cooled. Therefore, there is no risk of a large amount of water leaking as in the conventional method when attaching and detaching replacement parts that are directly water-cooled. Since water leakage can be prevented in this way, there are no electric shock accidents that previously occurred during arc machining work, and it is now possible to wipe up spilled water every time a replacement part is directly cooled by water. The troublesome work of having to do this becomes unnecessary.

[Brief explanation of the drawing]

FIG. 1 is a schematic front view showing an embodiment of the present invention, and FIGS. 2 to 4 are views showing other embodiments of the present invention, respectively.
5 is an end sectional view of an arc machining torch suitable for the arc machining apparatus according to the present invention. 2... Electrode (=replacement part), 8... Cooling water supply hose, 9... Cooling water drainage hose, 10... Arc processing torch, 11... Water tank, 16, 161 -1
63...Solenoid valve,]7...Water supply source agent Patent attorney Hiroshi Nakai

Claims (1)

[Claims] 1. In an arc processing apparatus equipped with an arc processing torch having a replacement part that is directly water-cooled, and a cooling water supply and drainage mechanism equipped with a water supply source connected to a cooling water circulation path of the torch, the cooling water supply and drainage The arc machining apparatus includes a cooling water-gas displacement mechanism that replaces the inside of the cooling water circulation path with gas before the operation of attaching and detaching the replacement parts.