JP2774308B2 - Wire cut electric discharge machine - Google Patents

Description

Description: BACKGROUND OF THE INVENTION The present invention relates to a wire cut electric discharge machine, and more particularly, to a slit for a workpiece to be used for, for example, forming a split mold for a cylindrical mold used for manufacturing tires and the like. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wire electric discharge machine capable of performing machining or cutting by using a plurality of wire electrodes in parallel.

[Prior Art] A wire-cut electric discharge machine generally cuts a workpiece, for example, by causing a wire electrode to which a discharge voltage is applied to travel and generating an electric discharge between the wire electrode and the workpiece. It is configured as follows. Hereinafter, a mold for manufacturing a tire such as an automobile will be described as an example of a workpiece, but the present invention is not limited to this.

When the mold for timer production is divided, a high-precision machined surface is required, so an electric discharge machine is used. However, slitting or cutting for forming the split mold for the cylindrical mold used in the conventional tire manufacturing is required. In this case, a wire-cut electric discharge machine configured to perform machining with one wire electrode is used.

[Problems to be solved by the invention]

When slitting or cutting a cylindrical mold used for tire production with a conventional wire-cut electric discharge machine configured to perform machining with one wire electrode, one wire is directed toward the center of the cylindrical mold. This slitting or cutting process has the disadvantage of causing uneven distortion due to internal stress. In addition, for example, when dividing into nine parts, it takes about 30 hours to obtain a high-precision processing surface. Was also a serious drawback.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned drawbacks. By employing a configuration in which a plurality of wire electrodes stretched on a workpiece are used for parallel processing, the processing time is reduced and distortion is reduced. An object of the present invention is to provide a wire-cut electric discharge machine suitable for, for example, dividing a die for manufacturing a tire.

[Means for solving the problem]

In order to achieve the above object, a wire-cut electric discharge machine according to the present invention divides a workpiece having an arc-shaped part, which is placed on a mounting base on a bed, into a workpiece having the arc-shaped part. A wire-cut electric discharge machine that performs machining for forming a column, a column erected on a bed, a ring-shaped first support disposed inside a workpiece having the arc-shaped portion, and the arc-shaped first support. A pair of a first support and a second support are provided by a pair of a ring-shaped second support disposed outside a workpiece having a portion and a moving device provided on each of the columns. A quill that moves up and down integrally with the body, and is provided in a pair on the first support and the second support, respectively, and is provided to extend the wire electrode in the radial direction, and is set at a predetermined angle indexing position. Multiple wire guards that are fixed as possible A workpiece having the above-mentioned arc-shaped portion mounted on a mounting base on a bed, comprising: a wire block pair; and a wire electrode traveling device for simultaneously traveling a wire electrode stretched between the wire guide block pair. The object is characterized in that the object is processed in parallel by the plurality of wire electrodes running at the same time and divided into a plurality of pieces.

[Operation] The work piece may be a rod-shaped work piece. For example, when the work piece is a cylindrical mold for tire production, the first support disposed inside and outside the cylindrical mold is used. Between the body (hereinafter referred to as the inner ring) and the second support (hereinafter referred to as the outer ring), there are a plurality of radially traveling radially outwards from the center of the cylindrical mold or from the center of the cylindrical mold. The wire electrode is stretched. Then, parallel slitting or cutting with the plurality of wire electrodes is performed on the cylindrical mold for tire production.

〔Example〕

FIG. 1 is a perspective view of a main part of an embodiment of a wire-cut electric discharge machine according to the present invention, and FIGS. 2 to 5 are explanatory views of an embodiment of a wire running extension of a wire electrode.

In FIG. 1, a bed 2 is provided with a mounting base 2 at the center thereof on a bed 1, and three columns 3A, 3B, 3C at equal angles are provided on the outside of the mounting base 2 (3C is clearly shown in the drawing). (Not shown) is erected on the bed 1. The mounting table 2 is provided with a clamp 4 and a cylindrical mold 5 as a workpiece.
Has been fixed. The cylindrical mold 5 is a mold used, for example, for manufacturing tires of automobiles and the like, and is illustrated in a cylindrical shape because the figure becomes complicated. In this specification, the cylindrical mold 5 is named. In fact, it should be understood as a mold for manufacturing tires. The column 3A is provided with a vertical movement moving device, for example, a quill feed screw 6, a female screw 7 screwed to the quill feed screw 6, and a quill vertical movement motor 8 for rotating the quill feed screw 6, and is attached to the female screw 7. The quill 9A can be freely moved up and down.
The quill 9 can be moved up and down similarly for the other columns 3B and 3C.
B and 9C (the quill 9C is not shown) are provided, and these three quills 9A, 9B and 9C are synchronized so that they move in the same manner. That is, the inner ring 11 as the first support and the outer ring 12 as the second support move up and down integrally via the mounting column 10 attached to the lower ends of the quills 9A, 9B and 9C. It has become. The inner ring 11 and the outer ring 12 are arranged at positions that come inside and outside the cylindrical mold 5 when lowered. Nine wire guide blocks 13 and 14 arranged at a predetermined degree are attached to the inner ring 11 and the outer ring 12 via insulating members 15 respectively. Each of the wire guide blocks 13 and 14 forms a pair, and a wire electrode is provided between the wire guide blocks 13 and 14 forming the pair.
When the wire guide blocks 13 and 14 are stretched, the wire guide blocks 13 and 14 are fixed in nine pairs in a direction in which the wire electrodes 16 are stretched toward the centers of the inner ring 11 and the outer ring 12 (FIG. 1). In the figure, only three sets are shown, and the remaining six sets are omitted.) That is, when the cylindrical mold 5 is slit or cut with the wire electrode 16, the direction of the slit or cut is processed toward the center of the cylindrical mold 5. The wire guide blocks 13 and 14 formed in the above-mentioned nine pairs are arranged so as to be set at a predetermined angle indexing position, and are fixed to the set angle indexing position during machining.

At the tip of the columns 3A, 3B, 3C, a zenith plate 25 is provided. The zenith plate 25 has nine wire reels 17A, 17B, 17
C (the wire reel 17C is not shown) is provided. For example, a wire electrode 16 wound on a wire reel 17A is connected to a tension roller 18A provided on a quill 9A,
After passing through a pair of wire blocks 13 and 14 via guide rollers 19A, 20 and 21, it is wound on a take-up reel 24B provided on the quill 9B via a guide roller 22 and a take-up roller 23B. .

Similarly, wire electrode 1 wound on wire reel 17B
6 is wound on a take-up reel 24C provided on a quill 9C not shown, and a wire electrode 16 wound on a wire reel 17C not shown is provided on a quill 9A as shown. The take-up reel 24A is adapted to be wound up.

In the wire electric discharge machine configured as described above, the inner ring 11 and the outer ring 12 are moved down with the downward movement of the quills 9A, 9B, 9C moving synchronously. tension·
The wire electrode 16 stretched between the wire guide blocks 13 and 14 forming a pair by the operation of the rollers 18A, 18B and 18C is always maintained at a predetermined tension. By applying a predetermined discharge voltage to the wire electrode 16 in such a state, a discharge is generated between the wire electrode 16 and the cylindrical mold 5, and the quill is discharged.
If 9A, 9B, 9C is lowered according to the processing speed, parallel slitting or cutting is performed simultaneously by nine wire electrodes 16. Simultaneously, slitting or cutting is performed, so that the internal stress of the cylindrical mold 5 is released evenly over the entire circumference, distortion is reduced, and division accuracy is improved.

When a short circuit occurs between the wire electrode 16 and the cylindrical mold 5, the short circuit is detected by a short circuit detecting device (not shown).
B and 9C are raised synchronously, and then lowered after a predetermined time to continue machining.

FIG. 2 is an explanatory view of one embodiment of the wire running extension of the wire electrode, and the nine wire electrodes 16 described in FIG.
FIG. 6 is a wire running diagram for machining nine locations at the same time. Arrows indicate the running direction of the wire electrode 16, and all of them point toward the center O of the cylindrical mold 5.

In this case, the cylindrical mold 5 is divided into nine parts by one processing, and the efficiency is the highest, but nine power supplies must be prepared.

As a method of reducing the number of power supplies for supplying the discharge voltage and increasing the processing efficiency, it is possible to configure a wire running system for each power supply as shown in FIG. 3 to FIG. That is, FIG. 3 shows a wire running diagram when processing is performed using three wire electrodes 16 and three power sources. In this case the first
When the predetermined processing is completed, the mounting table 2 is rotated by 1/3 turn, the processing is performed, and the mounting table 2 is further rotated by 1/3 rotation. Will be split. Therefore, a device for rotating the mount 2 by 1/3 turn is required. A configuration in which the columns 3A, 3B, and 3C are rotated instead of the rotation of the mounting table 2 may be employed.

FIG. 4 shows a wire running diagram when processing is performed with three power supplies using three wire electrodes 16 as in the case of FIG. In this case, one wire electrode 16 is run for each of the quills 9A, 9B, 9C shown in FIG. 1, and the mounting base 2 or the columns 3A, 3B are arranged similarly to the configuration shown in FIG. ,
A device that rotates 3C three times at a predetermined angle is required.

FIG. 5 shows a wire running diagram when three wires are processed in parallel by one wire electrode 16 at the same time. In this case the fifth
As shown in the drawing, the wire electrode 16 is configured to run, and a device for rotating the mounting table 2 or the columns 3A, 3B, 3C by 1/3 turn is required. Only one power supply is required.

In addition, it is also possible to adopt a configuration of a wire running in which nine wires are simultaneously processed in parallel with one wire electrode. At this time, only one power supply is required, and a device for rotating the mounting base 2 and the like is not required.

In the above description, an example in which the cylindrical mold 5 is divided into nine parts has been described. However, the present invention is not limited to nine parts and may be applied to an arbitrary number.

Also, the so-called centripetal direction in which the wire electrode 16 runs toward the center of the cylindrical mold 5 has been described.
On the other hand, a structure in which the wire electrode 16 travels in a radial direction from the center of the cylindrical mold 5 to the outside as shown in a part of FIG.

〔The invention's effect〕

As described above, according to the present invention, the processing speed can be greatly improved because of the configuration in which a plurality of wire electrodes can be processed in parallel. During processing, the internal stress of the workpiece is released evenly around the entire circumference, so that the occurrence of distortion is reduced and the division accuracy is improved.

Also, by using a wire running system for each power supply,
It is also possible to simplify the wire traveling system.

[Brief description of the drawings]

FIG. 1 is a perspective view of a main part of an embodiment of a wire-cut electric discharge machine according to the present invention, and FIGS. 2 to 5 are explanatory views of an embodiment of a wire running extension of a wire electrode. In the figure, 1 is a bed, 2 is a mounting table, 3A, 3B, 3C are columns, 5 is a cylindrical mold (workpiece), 6 is a quill feed screw, 7 is a female screw, 8
Is a quill vertical movement motor, 9A, 9B, 9C is a quill, 11 is an inner ring (first support), 12 is an outer ring (second support), 1
3, 14 is a wire guide block, 16 is a wire electrode, 17A, 17B,
17C represents a wire reel, and 24A, 24B, and 24C represent a take-up reel.

Claims (1)

(57) [Claims] 1. A wire-cut electric discharge machine for processing a workpiece having an arc-shaped portion placed on a mounting table on a bed to divide the workpiece having the arc-shaped portion. A column erected on the bed, a ring-shaped first support disposed inside the workpiece having the arc-shaped portion, and a ring disposed outside the workpiece having the arc-shaped portion A quill that moves up and down integrally with the set of the first support and the second support by a moving device provided on each of the columns; A plurality of wire guide block pairs provided on the support and the second support, each pair being provided to extend a wire electrode in a radial direction and fixed to be settable at a predetermined angle indexing position; , Between the wire guide block and the pair A wire electrode traveling device for simultaneously traveling the stretched wire electrodes, wherein the workpiece having the arc-shaped portion placed on the mounting base on the bed is processed in parallel by the plurality of wire electrodes traveling simultaneously. A wire-cut electric discharge machine characterized by being divided into a plurality of pieces.