JPS62181830A - Electric discharge machining device - Google Patents

Abstract

PURPOSE:To machine a workpiece which is set in a stationary condition and to make it possible to a high responsive control with no vibration being exerted to an electrode, by providing a plain bearing in a movable section of a bed supporting the electrode so that machining feed is made in X and Y axis directions in parallel with a machining bed. CONSTITUTION:An X-axis motor 11 and a Y-axis motor 13 are driven in accordance with signals from an NC control device to move tables 9, 12. Since plain bearings 15, 16, 17 are provided in slidable sections in the X-axis movable table 9 and the Y-axis movable table 12, so that the tables 9, 12 make into surface- contact with each other while the stationary sections thereof are strongly coupled with the movable sections. Particularly by using an electric-discharge- machined surface is used as a slide surface, lubricant is reserved in concavities and convexities in a matter-finishes surface so that it is possible to stably move the tables. Accordingly, the movement of a column 6 and an electrode 1 is controlled with no vibration accompanied with the movement. The responsiveness is made to be higher than that in the case of both workpiece 2 and the machining bed 5 are moved, thereby it is possible to enhance the speed and accuracy of electric discharge machining.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to an improvement of a 111 electric machining device that performs die-sinking electric discharge machining, wire-cut electric discharge machining, and the like.

[Prior art and problems]

A conventional electric discharge machining apparatus is configured to apply feed control in the X and Y axis directions to a machining table on the side of the workpiece in the rounding machining and wire cutting of die-sinking electric discharge machining. This is because it causes vibrations when applied to the head on the electrode side.
The wire electrode vibrates and short circuits, arcs, etc. interfere with stable machining, and the wire may break. The reason for the vibration is that since ball bearings and the like are mainly used for the movable parts, the contact area is small and strong engagement cannot be obtained, resulting in backlash and rattling. Therefore, the processing table on which the workpiece is mounted is moved, but when the workpiece is large, the heavy sharpening drive device requires a large torque.

Furthermore, even if a high-performance motor is used, there is a drawback that the response speed decreases because it moves a large amount of weight.

(Means for Solving the Problems) The present invention has been proposed in view of the above, and is such that the movement of a support head that supports an electrode is controlled, and a plane bearing is provided in the movable part. Preferably, the plain bearing has a surface that has been subjected to electric discharge machining and is formed into a smooth surface, which provides a smooth bearing action.

〔Example〕

The present invention will be explained below with reference to an embodiment of the drawings.

A wire electrode 1 is supplied from a reel 3 and wound onto a reel 4. Reference numeral 2 denotes a workpiece which is fixed to the workbench 5, faces each other to form a machining gap, supplies machining pulses from a pulse power source (not shown), and performs electrical discharge machining while repeating pulsed discharge. 6 is a column constituting an electrode support head, from which upper and lower supports 7.8 protrude and guide the wire electrode 1.

Reference numeral 9 denotes an X-axis moving table parallel to the processing table reference plane, to which the column 6 is fixed. 10 is the X-axis feed screw, 1
1 is the X-axis feed motor, 12 is the Y axis parallel to the processing table reference plane
An axis moving table, 13 is an X-axis feed motor, and 14 is a bed. Y-axis moving table 12 and X-axis moving table 9
A plane bearing 15 is provided between the bed 14 and the Y-axis moving table 2, and a plane bearing 16 is provided between the bed 14 and the Y-axis moving table 2.
．． 17 are provided. Of course, although not shown, plain bearings can be provided between the X-axis feed screw 10 and the neck 1 provided on the X-axis moving table 9, and between the Y-transport screw and the neck 1 provided on the Y-axis moving table 12. .

In the above, when machining is performed by repeatedly applying pulse discharge to the gap between the wire electrode 1 and the workpiece 20, which are moved with a predetermined tension and speed, cutting is performed by applying a machining shape feed between the two. Processing feed is applied to the electrode side with the workpiece 2 fixed. That is, by applying a program distribution signal from the NG control device to the X-axis motor 11 and the Y-axis motor 13 to control their drive, the X-axis moving table 9 and the Y-axis moving table 12
control the movement and feed the processing. Therefore, the wire electrode 1 is controlled to move to the desired shape while the workpiece 2 remains fixed, and the wire is cut.Since the heavy workpiece is not moved, the response speed is high, and high-speed, high-performance machining can be performed. I can do it.

Further, as described above, each movable part such as the X-axis moving table 9 and the Y-axis moving table 12 is provided with a plain bearing 1.
5, 16, 17, etc. are provided. Conventionally, movable parts were mainly provided with ball bearings, but by using plain bearings, the fixed part and the movable part are brought into contact over a wide area, and movement is controlled while the fixed part and the movable part are strongly connected.

Therefore, the column 6 fixed on the X-axis moving table 9 and the wire electrode 1 supported by this column do not vibrate due to movement control, and can be stably fed. In particular, by forming the sliding surface of a plain bearing using a surface processed by electrical discharge machining, the satin surface unique to electrical discharge machining can be used, and the fine irregularities of the satin surface can reduce friction. Lubricants such as oil and carbon can be stored there, allowing for stable, high-speed response movement control with enhanced lubricity.

In this way, vibration of the wire electrode 1 caused by machining feed can be removed and stable feed can be provided, so the wire electrode 1 is always guided straight at a predetermined speed.
It is possible to stably maintain the gap facing the workpiece 2 and perform processing by repeating stable pulse discharge, thereby reducing wire electrode breakage and increasing the processing speed.

In addition, the electrode is not limited to a wire electrode, but also when using an electrode with a complete shape or a simple shape electrode, and performing electric discharge machining by sending it to the X and Y axes, stable machining feed control must be performed in the same way. I can do it.

〔Effect of the invention〕

As described above, the present invention provides machining feed by controlling the movement of the support head that supports the electrode in the X-axis and Y-axis parallel to the processing table on which the workpiece is attached, so that the workpiece is fixed. The object to be moved on the electrode side is lighter than the conventional method of moving the workpiece side, the response speed is increased, and the feed can be controlled with high precision, making it possible to perform electrical discharge machining into the desired shape. Speed and processing accuracy can be improved.

In addition, in the present invention, the movable part is provided with a plain bearing to control the movement, so the fixed part and the movable part are strongly connected by a wide contact surface and move stably, reducing vibrations caused by feeding. Stable electrode feeding can be provided without causing any problems.

In particular, by forming the sliding surface of a plain bearing using an electric discharge machined surface, stable feed control can be achieved by reducing friction due to the matted surface, and by supplying lubricant to the matted surface, minute Lubricant can be stored in the irregularities, allowing stable feeding with enhanced lubricity. This makes it possible to improve the machining speed, machined surface roughness, machining accuracy, etc. of electrical discharge machining.

[Brief explanation of drawings]

FIG. 1 is a configuration diagram of an embodiment of the present invention. 1...Wire electrode 2...Workpiece 5...Working table 6...Column 7. 8...Support body 9...X-axis moving table 10...
...X-axis feed screw 11...X-axis feed motor 12...
...Y-axis moving table 13...Y-transport motor 14...Bed 15.16.17...Plane bearing Patent applicant

Claims (2)

[Claims] (1) In an electric discharge machining device that processes a gap between an electrode supported on a supporting head and a workpiece attached to a processing table by repeatedly applying pulse discharge, the supporting head is connected to an X-axis parallel to the processing table and A driving device for controlling movement on the Y axis is provided, a plane bearing is provided in a movable part by the driving device, and the driving device is controlled by a shape feed signal of copying or NC control. Electrical discharge machining equipment. (2) The electric discharge machining apparatus according to claim 1, which is provided with a plane bearing having a sliding surface formed by electric discharge machining.