JPH0155929B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an electrode guide unit for wire cut electric discharge machining, and particularly to an improved electrode guide unit that can effectively supply machining fluid to the wire electrode current-carrying part. It is.

[Prior Art] A wire-cut electrical discharge machining device is well known, which cuts a workpiece by passing a wire electrode through the workpiece and supplying discharge power between the wire electrodes, which are fed in a desired machining shape. Extremely suitable for cutting complex shapes. In this type of device, the wire electrode is guided to a desired feeding section by an electrode guide unit, and the wire electrode section from the power supply contact that supplies discharge power to the wire electrode to the processing section of the workpiece is so-called a wire electrode. Machining fluid is supplied to the current-carrying part from the electrode guide unit, and cooling, prevention of air discharge, and removal of machining powder are performed. In the wire electrode current-carrying section, it is desirable that the machining fluid is injected to form a liquid column surrounding the wire electrode, but with conventional equipment, a good machining liquid column is not formed and abnormal discharge or disconnection of the wire electrode occurs. There was a problem that this occurred. Conventional turbulence in the machining liquid column is mainly caused by interference of the overflow liquid flow with the machining liquid column.With conventional equipment, it was not possible to prevent this interference, resulting in turbulence in the machining liquid column. Accidents such as wire electrode breakage often occurred.

FIG. 1 shows a conventional electrode guide unit, in which an electrode guide unit 10 is used as an upper electrode guide unit for a workpiece 12, and a wire electrode 14 running through the workpiece 12 is guided to the electrode guide unit 10. It is then wound onto a take-up reel 16. Discharge power is supplied to the wire electrode 14 from the power supply contact 18, and the workpiece 1 is
2 cutting process is performed. A large current is applied to the current-carrying part of the wire electrode from the contact part with the power supply contact 18 to the machining part 100, and during this time machining fluid is supplied for cooling, prevention of air discharge, and removal of machining powder. The machining fluid is supplied from an inlet 20 of the electrode guide unit 10 and an auxiliary supply nozzle 22. The inlet 20 is integrally formed with the support 24, and a die-shaped wire electrode guide 26 is inserted and held in the tapered receiving hole 24a of the support 24, and the electrode is secured by a tightening body 28 screwed to the support 24. A guide 26 is positioned and fixed to the support 24. A cap 30 is screwed to the outer periphery of the support 24, and machining liquid is injected from its nozzle 30a toward the wire electrode 14 to form a machining liquid column.

[Problems with the prior art] According to the conventional upper electrode guide unit 10,
The machining fluid supplied from the inlet 20 is supplied to the nozzle 30a.
As is clear from FIG. 1, the machining fluid is injected from the wire electrode 14 to form a machining fluid column that surrounds the wire electrode 14. As is clear from FIG. The machining liquid is also supplied from the auxiliary supply nozzle 22, and as a result, the overflow liquid flow interferes with the machining liquid column, resulting in disturbance of the machining liquid column. That is, a part of the machining liquid from the nozzle 22 is transferred to the hollow body 28a of the clamping body 28 and the through hole 28 of the support body 24.
4b to the nozzle 30a of the cap 30 and contributes to the formation of a machining liquid column, but a part of it overflows from the electrode guide unit 10 and is shown by arrow A.
As shown in , the machining liquid column falls along the outer periphery of the cap 30 to the nozzle 30a, and as a result, the machining liquid column is disturbed by interference with the overflow liquid flow below the nozzle 30a, and cannot wrap the wire electrode 14. . Therefore, the machining fluid is not supplied to the machining section 100, and there are disadvantages in that air discharge is likely to occur and wire breakage accidents are easily caused.

FIG. 2 shows the electrode guide unit 10 described above.
is shown being used as a lower electrode guide, machining fluid is supplied to the unit 10 from the inlet 20, is injected from the nozzle 30a of the cap 30 to the machining part, and the hollow hole 28 of the clamping body 28
A column of machining liquid surrounding the wire electrode 14 is ejected from a. In the lower electrode guide unit shown in FIG. 2, a good column of machining liquid can be supplied to the machining section 100.
The overflow liquid flowing around the outer periphery of the cap 30 interferes with the machining liquid column injected from the hollow hole 28a, causing disturbance in the machining liquid column as shown in the figure. Wire breakage accidents are likely to occur at the contact portion 200 between the contactor 14 and the contactor 18.

Purpose of the Invention The present invention has been made in view of the above-mentioned conventional problems, and its purpose is to provide an improved electrode guide unit that can obtain a good machining liquid column without interference from overflow liquid flow. be.

[Means for Solving the Problems] In order to achieve the above object, the present invention has a wire electrode guide that guides a wire electrode to a processing portion of a workpiece, and a wire guided to the wire electrode guide. In an electrode guide unit for wire-cut electric discharge machining, which sprays machining fluid onto the electrode from a machining fluid jet nozzle to form a liquid column along the wire electrode, an opening for receiving machining fluid flowing from above the wire electrode guide; The present invention is characterized in that an overflow liquid reservoir is provided on the side thereof, and an overflow discharge port is formed for discharging a predetermined amount or more of the machining liquid into a flow path separate from the liquid column.

[Embodiments] Preferred embodiments of the present invention will be described below based on the drawings.

FIG. 3 shows a preferred embodiment in which the present invention is applied to an upper electrode guide unit, and the same members as in the conventional device shown in FIG.

A feature of the present invention is that the overflow liquid flow is prevented from joining the machining liquid column, and this is achieved by an overflow liquid reservoir 34 that allows the overflow liquid flow to flow into a separate flow path.

In the embodiment, an overflow reservoir 34 having an opening for receiving the machining fluid through the clamping body 28 is integrally formed in the cap 30, and the overflow reservoir 34 is provided with a discharge port 36. The machining fluid supplied from the auxiliary supply nozzle 22 is temporarily stored in the overflow reservoir 34, and the overflow fluid is directly discharged from the overflow discharge port 36 to a discharge tank (not shown) without flowing to the cap 30. Therefore, there is no interference between the overflow liquid flow and the machining liquid column, and the machining part 100 is sufficiently surrounded by the machining liquid column, so that good cooling and other effects can be achieved.

[Effects of the Invention] As explained above, according to the present invention, the machining liquid column and the overflow liquid flow are reliably separated and the machining liquid column is prevented from being disturbed. Encased in pillars, it can provide good cooling, prevent air discharge, and remove machining powder.
It is possible to reliably prevent wire electrode breakage accidents.

[Brief explanation of drawings]

Fig. 1 is a sectional view showing a conventional upper electrode guide unit, Fig. 2 is a sectional view showing a conventional lower electrode unit, and Fig. 3 is a sectional view showing a preferred embodiment of the electrode guide unit according to the present invention. be. In each figure, the same members are given the same reference numerals; 10 is an electrode guide unit, 12 is a workpiece, 14 is a wire electrode, 26 is a wire electrode guide, 34 is an overflow reservoir, and 36 is an overflow outlet.

Claims (1)

[Claims] 1 It has a wire electrode guide that guides the wire electrode to the processing part of the workpiece, and a machining fluid jet nozzle jets machining fluid onto the wire electrode guided to the wire electrode guide to form a liquid column along the wire electrode. The wire-cut electric discharge machining electrode guide unit to be formed has an opening that receives the machining fluid flowing from above the wire electrode guide, and an overflow that discharges a predetermined amount or more of the machining fluid into a flow path separate from the liquid column at the side part. An electrode guide unit for wire cut electrical discharge machining, characterized in that it is provided with an overflow liquid reservoir formed with a discharge port.