JPS60213427A - Wire-cut electric discharge machining device - Google Patents

Abstract

PURPOSE:To prevent an electrode from being broken, and as well to enhance the efficiency of machining, by adjusting the spaces between stationary pulleys and movable pulleys, and as well by winding up the wire electrode while it is reciprocated in the vertical, lateral or longitudinal direction in a machining section. CONSTITUTION:A wire electrode 1 paid out from a pay-out reel 8 and having passed stationary pulleys 20 and movable pulleys 21 in several stages, passes along an energizing brush 6, a guide 5 and a workpiece 2, then passes stationally pulleys 20' and movable pulleys 21' in several stages after passing along the other guide 5', an energizing brush 6' and guide rollers 7, 7', and is then wound up by a winding reel 8'. Meanwhile, by rotating a motor 24 in a predetermined cycle and by predetermined rotating angle, a female screw 25 is rotated through gears 23, 23' so that the movable pulleys 21, 21' are laterally reciprocated in a predetermined moving distance at a high speed, and therefore, the wire electrode 1 may be wound up by a length corresponding to a consumption of the electrode during electric discharge machining. If the movable pulleys 21, 21' and the stationary pulleys 20, 20' are arranged in the vertical or longitudinal direction, they move in the vertical or longitudinal direction.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a wire-cut electrical discharge machine, and particularly to prevention of wire electrode breakage and improvement of machining efficiency.

The present invention relates to an electric discharge machining apparatus having a wire electrode high-speed reciprocating feeding device suitable for the above.

[Prior art]

In wire cut electrical discharge machining, as shown in FIG.
', the wire electrode 1 is accurately guided by the guide 5 and 5', and pulses from the processing pulse power source 4 are applied to the wire electrode 1 and the workpiece 2 through the energized brushes 6 and 6'. is given between. A machining fluid is supplied to the machining section by a machining fluid supply nozzle 3, and a workpiece 1 is arbitrarily positioned by an NC device (not shown) to cut or cut out the workpiece.

Wire electrodes typically have a diameter of o, oaxmφ to 0.31
Wires made of copper, brass, steel or other alloys are used. This type of machining is based on the principle of electric discharge machining, in which the workpiece 2 is thermally melted by pulsed intermittent arc discharge and then removed. At this time, the wire electrode side is also consumed and the diameter of the wire electrode 1 becomes smaller, so the winding
Wire wear is compensated for by constantly supplying new wire by successively winding the wire electrode 1 with the reel 8'. Furthermore, the tensile strength of the wire electrode 1 decreases due to the arc heat, making it more likely to break. To prevent wire breakage, in order to cool the wire electrode, it is desired to increase the winding speed of the wire electrode to shorten the time that the wire is exposed to the arc, but the wire electrode wound on the feeding reel 8 is consumed that quickly. , long-term continuous machining becomes impossible. Also.

Japanese Unexamined Patent Publication No. 58-45822 discloses a technique in which a wire 1 is wound around a rotating drum 10 as shown in FIG. 2, and the rotating drum 10 is rotated at high speed with the wire 1 in an endless state.

In this case, the surface of the wire electrode is plated by the plating device 11 in order to compensate for the wear of the wire electrode. However, since the wear of the wire electrode is not uniform, it has been impossible to make the diameter of the wire electrode constant.

In addition, if the machining fluid supply pressure from the machining fluid supply nozzle 3 is increased to improve the cooling effect of the wire electrode, the fluid in the machining area will swell, so there is a practical limit to increasing the machining fluid pressure. have

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to provide a wire-cut electric discharge machining apparatus having a wire electrode high-speed reciprocating feeding device that prevents wire electrode breakage in wire-cut electric discharge machining and improves machining efficiency.

[Summary of the invention]

In order to achieve the above object, the present invention provides a device for successively winding a wire electrode in a wire-cut electrical discharge machining device, and a pulley having several stages at one time in the vertical direction of the guide, or in the horizontal direction, or between the front and rear of the wire electrode. The axes of the pulleys on both sides are periodically moved in opposite directions continuously or at arbitrary intervals, thereby causing the wire electrode to reciprocate in the up-down, left-right, or front-back directions in the processing section, and at the same time, the above-mentioned winding. It is characterized by being wound up using a winding device.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to FIG. In this figure, the same parts as those shown in FIG. 1 are given the same reference numerals. 20 and 20' indicate a fixed pulley group having a plurality of pulleys; 21 and 21' a movable pulley group having a plurality of pulleys that are movable in the left-right direction and around which the wire electrode 1 is wound; 22; , 22' is the movable pulley group 21
The power transmission male screws 23, 23' for reciprocating the 21' left and right are gears for rotating the female screw 25, and the gear 23 is formed on the outer periphery of the female screw 25. Reference numeral 24 indicates a motor for driving the gear 23'. Further, 7 and 7' indicate guide rollers, respectively.

Next, the present invention will be explained in detail. The wire electrode l fed out from the feed reel 8 passes through the fixed pulley group 20 and the movable pulley group 21 in multiple stages, passes through the energizing brush 6, the guide 5, and the processed product 2, and then passes through the other guide 5' and the energizing brush 6. ′,
After passing through the guide roller 7.7', the take-up reel 8 passes through another fixed pulley 20' and a group of movable pulleys 21' in multiple stages.
' The wire electrode is wound up. The winding speed is adjusted by driving the winding reel by a motor (not shown), and the tension of the wire electrode is applied by a brake motor (not shown) brought into contact with the feed reel 8. On the other hand, motor 24 rotates female screw 25 via gears 23 and 23'. By rotating this female screw, the movable pulley groups 21, 21' are moved to the left or right. When the motor 24 is rotated at a constant period and at a constant rotation angle, the movable pulley groups 21 and 21' reciprocate to the left or right with a constant movement amount. The details will be explained later. Here, first, it will be explained that the wire electrode 1 is sent out and reciprocated at high speed from side to side. FIG. 4 shows a detailed view of the fixed pulley group 20, 20' and the movable pulley group 21, 21'. The pulley 201 is bonded to the outer race of the bearing 202, and the shaft 204 is inserted into the inner race of the bearing 202, and this inner race is fixed to the shaft 204 by an inner race fixing ring 203.

The plurality of inner races are attached to the screw 2 at the left end of the shaft 204.
The pulley group 201 is fixed to the stepped portion 207 of the shaft by a nut 206 for screwing to the shaft, and each pulley group 201 can freely rotate independently. Also,
The shaft 204 is provided with a screw hole 208 for connecting the male screw 22, 22'. Moving pulley 21.2
A wedge sliding surface 209 for smooth sliding is provided on the end surface of the shaft 1', and a fixed wedge surface 210 on the receiving side is formed on a bed serving as a base. When the reciprocating pulley moves left and right, the following relationship holds between the reciprocating length W and the moving distance 1ml of the wire electrode 1: l=2nmW However, n is This is the number of pulleys, and the larger the number, the larger l becomes, and the longer the reciprocating length of the wire electrode 1 becomes. In this way, the wire electrode 1 can be reciprocated at high speed, and the wire electrode 1 can be wound up by the take-up reel by the amount of electrode consumption during electrical discharge machining.

Next, the driving of the movable pulley groups 21 and 21' will be explained. In FIG. 5, 301 and 302 are limit switches provided on both sides of the movable pulley.
When the movable pulley presses 01 or 302, the contact signal of the pressed limit switch reverses the direction of rotation of the motor 24 sent to the motor controller 303. That is,
When the moving pulley moves to the right due to clockwise rotation and presses the limit switch 301, the limit switch 301
In response to the signal, the motor 24 is reversed, rotates to the left, and moves to llIh? I# The storm moves to the left. Next, when the limit switch 302 is pressed, the motor 24 rotates clockwise and the pulley again moves to the right.

The above example shows the case where the movable pulley moves in the left and right direction, but the movable pulley 21.21' and the fixed pulley 20.20'
It may be configured to move in the up-down direction or the front-back direction by arranging them top and bottom or front and back. In addition, although the reversal drive of the moving pulley has been shown in terms of the method using the IJ Mitsutswitch, as shown in Fig. 6, the arm 401
It is also possible to provide a configuration in which the movable pulleys 201 and 201' are reciprocated in the rotational direction by the vertical semi-rotational shaft 402.

Diagram M7 shows the relationship between the wire electrode feed speed and the allowable current that can be passed through the wire electrode, that is, the wire current carrying capacity.By increasing the wire feed speed, the cooling effect due to high-speed feeding in the machining fluid can be improved. This shows that the wire current carrying capacity can be increased.

In other words, the winding speed of the conventional wire electrode is 5m7fri.
In this case, the current carrying capacity was 14 people, but as in the present invention, the wire feeding speed was 100 mAnin.
If it increases to 5OA, it can be improved to 5OA.

〔Effect of the invention〕

According to the present invention, the wire electrode can be moved at high speed and the continuous processing time of the wire electrode is the same as before.
It has high efficiency, high precision, and can prevent wire electrode breakage, so it has great industrial effects. The specific effects and setting conditions of the present invention are shown below.

Wire electrode material: Brass 9.2 mtφ Winding speed of wire electrode: 2 m/min, Reciprocating speed of wire electrode: 100 m/min Reciprocating distance of wire electrode: 1.5 m Material of workpiece: Thickness of workpiece: 8011C & Above As a result of machining with an average pulse current of 25 A depending on the machining conditions, it was confirmed that the machining speed was conventionally about 1 m/min, but according to the present invention, it was possible to achieve a high machining speed of about 3 m/min. .

[Brief explanation of the drawing]

#I1 and 82 are configuration diagrams of a conventional wire-cut electric discharge machining device, FIG. 3 is a configuration diagram showing an embodiment of the present invention, FIG. 4 is a diagram showing details of a part of FIG. 3, and FIG. Figure 5 is
FIG. 6 is a detailed view showing another embodiment of the wire moving pulley drive shown in FIG. 5. FIG. FIG. 7 is a diagram showing the relationship between wire feeding speed and wire current carrying capacity according to the present invention. DESCRIPTION OF SYMBOLS 1... Wire electrode, 2... Processed product, 4... Processing pulse power supply, 20.20'... Fixed pulley, 21, 2
1'...Reciprocating pulley, 22.23...Male screw,
24...Motor, 25...Female screw, 301, 3
02...Limit Switch Patent Attorney Akio Takahashi 11 $5 Figure $6 Figure

Claims (1)

[Claims] In wire-cut electrical discharge machining equipment that performs machining using intermittent arc discharge generated by pulsed power supplied between a wire electrode and a workpiece, there is a fixed pulley group in which multiple pulleys are individually rotatably connected, and a fixed pulley group in which multiple pulleys are individually connected. a movable pulley group rotatably connected to the movable pulley group, and a drive device that moves the movable pulley group and adjusts the distance between the movable pulley group and the fixed pulley group, and the wire electrode is provided between the fixed pulley and the movable pulley. A wire-cut electrical discharge machining device characterized by being designed to be stretched.