JPS61260935A - Device for feeding liquid in wire electric discharge machine - Google Patents

Abstract

PURPOSE:To eliminate change in the temperature of a machining liquid, obtain high machining accuracy, and eliminate the need for using a fan cooler on the outside of a clean liquid tank by providing a pump for feeding a machining liquid to a machine body and a heat exchanger, being immersed in said clean liquid tank. CONSTITUTION:A machining liquid which is controlled to be at a room temperature by means of a unit cooler 35, is fed through a feed pump 50 and a heat exchanger 54 which are immersed in the liquid. Since the machining liquid with the same temperature as room temperature and without a partial temperature difference, is fed to the heat exchanger 54 by means of a liquid churning device 60, its exchanging efficiency is improved, and the accuracy for controlling liquid temperature is high. Also, the liquid temperature can be controlled in its maintenance with high accuracy even when a rapid filling pump 52 is used or when the capacity of a feed pump has changed due to the operation of a selector solenoid valve 25. Accordingly, any change in the temperature of machining liquid will not take place, obtaining a high machining accuracy.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a machining fluid supply device in a wire electrical discharge machining machine equipped with a machining fluid cooling mechanism.

[Conventional technology]

A conventional example of a machining fluid supply device for a wire electrical discharge machining apparatus equipped with a machining fluid cooling mechanism is shown in FIG.

That is, the machining fluid storage tank 10 of the machining fluid supply device 1 that sends and discharges machining fluid to and from the machining tank of the machine body 22 of the electrical discharge machining apparatus is a sewage tank 14 that stores the sewage 15 discharged from the machining tank.
and a clean liquid tank 12 that supplies clean liquid 16 to the processing tank, and the dirty liquid 15 in the dirty liquid tank is passed through a dirty liquid check valve 29 & and a dirty liquid filter pump 16 to enter the clean liquid tank. The liquid is fed under pressure to a filtration filter 18 and filtered to form a clear liquid 16.

Next, the fresh liquid can be rapidly filled into the processing tank through the rapid filling check valve 29b1, the rapid filling pump 27, and the fan cooler 60, and the fresh liquid can be rapidly filled through the check valve 29C1 and the supply pop/p 20. A switching electromagnetic valve 25 is interposed between the pump and the cooler through a fan cooler 24 and branchedly connected to the fresh liquid tank, so that the hydraulic pressure and flow rate of the supplied fresh liquid can be switched between two stages by opening and closing the valve. Furthermore, the temperature of the fresh liquid 16 in the fresh liquid tank is separately controlled by a unit cooler 255 so that it is equal to room temperature.

Therefore, in the conventional machining fluid supply device described above,
Generally, the machining fluid that has become clear fluid 16 is circulated through the yarn path such as the supply reverse valve, but when an abnormality occurs when the machining fluid escapes from the pump section and air is sucked in, the expansion, quick filling check valve, etc. The road can be activated to prevent dry running.

[Problem that the invention seeks to solve]

However, the machining fluid controlled at room temperature by the conventional supply device 11ri and its unit cooler 65 is supplied to the machine body 2.
2, a temperature rise occurs due to the supply pump 20 and the rapid filling pump 27, and a temperature difference occurs due to the difference in the capacity of each pump. Generally, in a wire electric discharge machining apparatus, machining accuracy is significantly reduced because a temperature difference occurs due to a change in the capacity of the supply pump due to the opening and closing operations of the switching solenoid valve 25. In addition, since the fan coolers 24 and 50 are installed outside the fresh liquid tank for the purpose of cooling the machining liquid, the room temperature increases only in the heat exchanger, and as a result, the machine body 22 is heated. In addition to causing deformation and lowering machining accuracy, the noise of the fan cooler inevitably deteriorates the working environment.

This invention solves the problem of temperature rise due to heat generation of the supply pump and rapid filling pump, which are disposed outside the clear liquid tank, of the machining liquid in the clear liquid tank, which is controlled at room temperature by a unit cooler, and due to the difference in the capacity of each pump. Deterioration in machining accuracy due to temperature changes due to temperature differences or fluctuations in the capacity of the supply pump; further deterioration in machining accuracy due to an increase in room temperature due to both fan coolers installed outside the fresh liquid tank; and also due to noise from the fan cooler. We aim to eliminate the deterioration of the working environment.

[Means for solving problems]

In this invention, a heat exchanger is disposed in each of the machining liquid in a fresh liquid tank whose temperature is controlled to be the same as room temperature by a unit cooler, and the machining liquid is circulated in the fresh liquid tank. It is equipped with a stirring device.

[Effect]

Therefore, in this invention, since the machining fluid is stirred and circulated in the tank, local differences in the fluid temperature are avoided, and heat generation is caused by the provision of the supply pump and rapid filling pump in the cleaning fluid tank. The temperature of the processing fluid in the fresh liquid tank is controlled by the unit cooler to be the same temperature as the room temperature, without raising the room temperature by simply transferring heat to the processing fluid in the tank. Temperature changes due to fluctuations are exchanged by a heat exchanger immersed in the fresh liquid tank and the temperature is always controlled to be the same as room temperature, so there is no reduction in processing accuracy or deterioration of the working environment.

〔Example〕

Next, referring to the drawings showing an embodiment of the present invention, in FIG.
The processing liquid storage tank 10 stores the waste liquid 1 discharged from the processing tank.
5 and a clean liquid tank 12 that supplies clean liquid 13 to the processing tank. Then, the sewage 15 in the sewage tank is transferred to the sewage check valve 29m and the sewage filter pump 16.
is forced to pass through the filter 18 in the fresh liquid tank and filtered to form a fresh liquid 16 and stored in the fresh liquid tank, and the fresh liquid is heated to the same temperature as room temperature by a two-nit cooler 65. control so that Further, the clear liquid tank is equipped with a machining liquid agitator or a #60 machining liquid to agitate and circulate the machining liquid in the tank to prevent local differences in liquid temperature. A rapid filling pump 52, such as a submersible pump, which operates by being immersed in the liquid is disposed in the machining liquid in the liquid tank, and a heat exchanger between the pump discharge side and the machine body is immersed in the clear liquid tank. connection via a device 56,
Furthermore, a supply pump 50 such as a submersible pump that operates by being immersed in the liquid is disposed in the machining liquid in the fresh liquid tank, and a portion between the pump discharge side and the machine body is immersed in the fresh liquid tank. Another heat exchanger 54 is interposed and connected. Note that by branching the connecting pipe on the machine main body side and communicating with the inside of the two-stage tank, the supply pump 50 can
- The hydraulic pressure and flow rate of the supplied fresh liquid can be changed in two stages according to the opening and closing of the solenoid valve. Therefore, the machining liquid in the fresh liquid tank 12 is supplied to the machine body 22 via the heat exchanger 54 by the supply pump 50, but since the pump is composed of a submersible pump or the like and is immersed in the machining liquid, Heat exchange is performed with water, which has better heat exchange properties than air, and heat generation is suppressed to a minimum.
The temperature rise of the processing fluid after passage can be kept to a minimum. Furthermore, when the processing fluid passes through the heat exchanger 54, the temperature increase caused by the pump is also controlled to be the same as the room temperature.
The heat exchanger that exchanges heat with the machining fluid in the fresh liquid tank and can control the machining fluid temperature to the same temperature as room temperature is equipped with a machining fluid stirring device 6.
0, the machining fluid at the same temperature as room temperature without any local temperature difference is always stably supplied, improving the heat exchange efficiency and providing high accuracy in controlling the fluid temperature. In addition, when the rapid filling pump 52 is used, the switching solenoid valve 25 is activated.
It is needless to mention in detail that even if the pumping capacity of the supply pump changes, the temperature of the machining fluid can be controlled to be kept at the same temperature as room temperature with high precision, as in the case of using the supply pump described above.

Wow, if you use the unit cooler mentioned in the example above,
Since the rise in room temperature caused by the heat radiation of the heat exchanger of the cooler is eliminated, the above-mentioned effects are greatly improved.Furthermore, in the above-described embodiment, the processing part is immersed in the processing tank of the machine body 22, and the processing is carried out without any damage. Although we have described an example of performing electrical discharge machining by jetting machining fluid into the machining part,
It is not true that the same effect can be achieved.

〔Effect of the invention〕

As described above, in this invention, the pump and heat exchanger for supplying the machining fluid to the machine body are immersed in the dam, which prevents temperature changes in the machining fluid and improves machining accuracy. This invention has many practical benefits, such as easily realizing wire electrical discharge machining with high efficiency, and eliminating the need to install a fan cooler outside the fresh liquid tank, which eliminates noise and improves the working environment.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram of a circuit system showing an embodiment of the present invention;
FIG. 2 is an explanatory diagram of a circuit system of a machining fluid supply device in a conventional wire electric discharge machining device.

Claims (2)

[Claims] (1) The machining fluid is placed between the discharge side of the pump that sends fluid to the machine body of the electrical discharge machining device placed in the machining fluid in the fresh fluid tank whose temperature is controlled to be the same as room temperature by a unit cooler, and the machine body. What is claimed is: 1. A machining fluid supply device for a wire electric discharge machining device, characterized in that a heat exchanger is disposed therein by immersing the machining fluid in the clear fluid tank, and a stirring device is provided so that the machining fluid circulates within the fresh fluid tank. (2) A machining fluid supply device in a wire electrical discharge machining apparatus according to claim 1, wherein the pump is a submersible pump.