JPH0271924A - Wire-cut electric discharge machining device - Google Patents

Abstract

PURPOSE:To previously prevent lower pressure of machining liquid fed into an electric discharge gap without the leakage of the machining liquid from the inlet and outlet of a wire electrode to a nozzle by providing a sealing means at the inlet of the nozzle portion of the wire electrode. CONSTITUTION:A labyrinth seal 14, comprising grooves 15 and teeth 16, is provided at the inlet of a nozzle 7 through which a wire electrode 1 is penetrated. Flow 10d is thus given such a direction that the leakage 10c of machining liquid at this inlet is brought into collision against the portions of the teeth 16 and made to U-turn into the grooves 15. Each of such a flow 10d is caused at the portions of respective grooves 15 and teeth 16 to weaken the flow velocity of the machining liquid in sequence of going upward and to lower the pressure. In result, the pressure of the flow 10e of the machining liquid, let to the outlet of the labyrinth seal 14, is almost near to atmospheric pressure to reduce its flow rate, so that the leakage of the machining liquid from the inlet and outlet of the wire electrode 1 to the nozzle 7 is preventive and the flow rate and velocity of the machining liquid fed into a gap between the wire electrode 1 and a work piece is kept constant.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a wire-force electrical discharge machining device, and particularly to a device for preventing leakage of machining fluid.

[Conventional technology]

FIG. 6 is a configuration diagram showing an example of a conventional wire-cut electric discharge machining device, in which (1) shows the wire iI! fed out from the supply bohin (2). The poles (3) are brake rollers that are connected to electromagnetic brakes (8a, j and apply a predetermined tension to the wire electrodes (1). It is an idler that changes the direction. Also, (5) is a lower positioning kite, (6)
are lower positioning kites, which are arranged inside the upper and lower machining liquid jetting nozzles (7) and (8), respectively. (9) is a T-shaped pump that supplies machining fluid, and a ring is released between the wire electrode (1) and the workpiece U! The wire electrode (1) is supported by the lower guide (5) and the lower guide (6), and is oriented in a predetermined direction with respect to the workpiece (2). positioned.

Note that the wire is a wire feed roller.

The missing number ζ operation will be explained. First, drive the pump (9),
While spouting machining fluid αG, the pole (1) and workpiece 0 are attached to the wire.
Apply a pulse voltage between the wire electrodes (1).
An arc discharge is generated between the opposing electrodes of the workpiece and the workpiece (L), and the machining fluid in the minute gap is rapidly vaporized by this heat (hereinafter referred to as vaporization explosion).

The workpiece is melted by the thermal energy generated during the discharge, and this melted portion is scattered and removed by the vaporization explosion. 1. Keep the opposing 7 minute gaps constant and release 11E.
kContinuously do 1 moment +%! The relative movement between the pole (1) and the mouth of the workpiece is usually carried out by Method 1, which controls the shell value of the X-Y cross table (not shown in the figure). In this way, the discharge is repeated, and the By controlling the table, machining grooves are continuously formed and the workpiece (2) is machined into an arbitrary shape.

In the above case, the melted portion of the workpiece is proportional to the input power, but the amount removed also depends on the size of the vaporization explosion. t), D Loespeed requires increasing the thermal energy for melting and removing the melted part quickly.

[Problem to be solved by the invention]

In conventional wire-cut electrical discharge machining equipment, the machining fluid is mainly pure water, and the input power is supplied by pulsed current. When attempting to improve cutting speed by increasing input power, processing quality cannot be improved unless the removal efficiency of the generated slurry and gas is increased.

As shown in FIG. 7, the flow of machining fluid is a flow along the surface of workpiece 0 (10aJ) and a flow flowing into the discharge gap (lo
h) and the nozzle (7) from the penetrating part of the wire electrode (1) (10c), and the leakage from the penetrating part of the wire electrode (1) is particularly high (<1oC). I have an assignment.

[One-shot method to solve the problem] This? In order to prevent machining fluid from leaking from the part where the wire pole passes through the nostalle wire, the wire cart part release processing apparatus for group P has a gold film sealing means at its inlet.

[For use]

The wire electrical discharge machining bag according to the present invention is provided with a sealing means at the nozzle entrance of the wire electrode to prevent leakage of the machining fluid supplied between the discharge electrodes, and the machining fluid is supplied to the gap between the wire electrode and the workpiece. Liquid filtration and flow rate can be kept constant.

[Embodiments of the invention]

FIG. 1 is a sectional view illustrating the invention in detail, and FIG. 4 is a diagram illustrating its operation.

Hereinafter, one embodiment of the present invention will be described in detail with reference to the drawings. In FIG. It's teeth. A sectional view of this part is shown in Figure 2 and Figure 8.Hereinafter, the sealing of the entrance of the wire electrode (1) to the upper nozzle (7) will be explained.

The pump (9) is operated to supply machining fluid, and the machining fluid is fully pressurized into the discharge gap. At this time, the flow of machining fluid is the flow on the surface of the workpiece (2) (10aJ), the flow flowing into the discharge gap (ioJ), and the leakage at the inlet (10J is the same as the conventional one, but (100J) is the flow flowing into the discharge gap (10aJ) When attached, it collides with the tooth αG, causing a flow in a direction that makes a U-turn into IQ119.

This action occurs at each clearing point and tooth αG, and the flow rate becomes weaker and the pressure decreases as one moves upward.

Therefore, the flow of machining liquid (106) reaching the outlet of the sealing means α is close to atmospheric pressure and the flow rate is extremely small.

The seal formed by the action of the groove α9 and the teeth αG will be referred to as a labyrinth seal I hereinafter.

This labyrinth seal α4 can be configured so that the wire if&(1) does not come in contact with the labyrinth seal α4, so that it is easy to pass the wire through the pole (1). Also, there is no need to damage the wire electrode (1) or apply extra tension.

The sealing action naturally depends on the number and shape of the grooves (to) and teeth αG, and the gap r between the wire wire pole (1) and the tooth αG, and the smaller the gap, the better. The more the better.

In addition to the rectangular shape shown in FIG. 4, the teeth can have a structure that facilitates generation of vortices in the grooves as shown in FIG. 5.

The construction materials of this device are metal, plastic, and resin.

The column can be constructed of any ceramic material.

Although the upper nozzle (7) portion will be described here, the same effect can be obtained even if the present invention is applied to the lower nozzle (8) portion.

〔Effect of the invention〕

As described above, the present invention eliminates the leakage of machining fluid from the inlet and outlet of the wire electrode to the nozzle, and does not reduce the pressure of the machining fluid supplied to the discharge gap.

However, the flow rate of the flow, Flow 1, can be maintained at a predetermined value, and the discharge efficiency of machining slurry can be improved by increasing the pressure of the machining fluid, so the cleaning of the discharge gap is faster, and the w
It is possible to reduce the amount of force input and greatly improve machining speed.

Note that the pressure for processing is 20 to 80#/d, but 1
It has been confirmed that it exhibits sufficient sealing effect even under pressures of 00 to 150 #f/d.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing the configuration of an embodiment of the present invention, FIG. 2 is a sectional view taken along the line 1-1 in FIG. is an enlarged sectional view explaining its action, No. 6
Figure 6 is a sectional view showing the configuration of another embodiment of the present invention, and Figures 6 and 7 are sectional views showing the configuration of a conventional device. In the figure, (1) is the wire gt pole, (7) and (8) are the machining fluid jet nozzles, αO is the machining fluid, @ is the workpiece, α is the labyrinth seal, (to) is the groove, and αG is the tooth. It is. Note that the same reference numerals in the drawings indicate corresponding parts.

Claims (1)

[Claims] A wire-cut electrical discharge machining device that performs electrical discharge machining while supplying machining fluid to a minute gap where a wire electrode and a workpiece face each other is equipped with a nozzle through which the wire electrode penetrates, and a A wire-cut electric discharge machining apparatus characterized in that a sealing means is provided in the wire electrode through-hole portion coaxially with the wire electrode.