JPS61244413A - Wire cut electric discharge machine of forward and return two-wire type - Google Patents

Abstract

PURPOSE:To extend a time for unmanned operation, by simultneously further automatically performing the work, drilling a machining prepared hole prior to machining, and the work, inserting forward and return two wire electrodes to be extended through said prepared hole, in the case of a wire cut electric discharge machine of forward and return two-wire type. CONSTITUTION:A machine is operated first by moving an electrode guide lever 14 to the bottom to hook a wire electrode 4 to a grooved chip 14a. Next the machine, further moving the electrode guide lever 14 to the bottom, applies a machining voltage pulse between a workpiece 20 and the wire electrode 4 while reciprocates a rotary disc 15 to be turned in a range of 180 deg. or more. Here the machine, generating an electric discharge between the wire electrode 4 and the workpiece 20, drills a prepared hole 20a. Thereafter the machine, extending the electrode guide lever 14 further to the bottom, turns back the wire electrode 4 by a turn back guide roller 13a.And the wire electrode, being brought into contact with each other by four rollers, performs electric discharge machining, but this machine can perform unmanned operation for a long time.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a wire-cut electric discharge machining device, and in particular, by folding back one wire electrode, two reciprocating wire electrodes are brought closer to the workpiece in the machining area. The present invention relates to an improvement of a reciprocating two-wire wire-cut electric discharge machining apparatus that performs electric discharge machining while running in opposing directions.

[Conventional technology]

The applicant previously filed Japanese Patent Application No. 59-260029,
No. 9-260030, Japanese Patent Application No. 60-000391, etc., disclose wire-cut electric discharge machining in which machining is performed by folding back one wire electrode so that two reciprocating wire electrodes closely face each other to the workpiece. disclosed the device.

With the above configuration, two reciprocating wire electrodes are run in parallel in the processing section, so one
Compared to machining with a regular wire electrode, the machining gap formed between the workpiece and the workpiece is wider, and a large amount of machining fluid can be easily supplied into the gap by a nozzle, etc., which allows cooling. The effect increases, making it possible to perform machining with a large current, improving machining efficiency, and if the two wire electrodes are run sufficiently close or even in contact, bending of the electrodes due to discharge pressure can be reduced. Many advantages can be obtained, such as eliminating problems and enabling high-precision machining.

[Problem that the invention seeks to solve]

Therefore, even when machining is performed using two reciprocating wire electrodes as described above, a pilot hole for inserting the wire electrode through the workpiece is drilled in advance, and this hole is opened at the start of machining. Although it is necessary to insert two wire electrodes back and forth through the prepared hole, this work is more troublesome than when only one wire electrode is used, and it is extremely difficult to perform this automatically.

Therefore, there is also a limit to long-term unmanned machining using a reciprocating two-wire wire-cut electric discharge machining apparatus.

The present invention has been made to solve the above-mentioned problems, and its purpose is to provide a reciprocating two-wire wire-cut electric discharge machining device in which drilling a pilot hole for machining prior to machining is an operation; The object of the present invention is to provide a device that can simultaneously and automatically insert two wire electrodes back and forth into the prepared hole.

[Means for solving problems]

In order to achieve the above object, the first form of the reciprocating two-wire wire-cut electrical discharge machine according to the present invention has a guide groove at its free end that is shallower than the diameter of the wire electrode used. , an electrode guide rod supported so as to be movable along its central axis and rotatable around its central axis, a servo feed device for processing and feeding the electrode guide rod in the direction of its central axis, and the electrode A servo rotation device is provided for rotating the guide rod about its central axis.

Further, in the second embodiment of the reciprocating two-wire wire-cut electrical discharge machining apparatus according to the present invention, a grooved roller having a guide groove shallower than the diameter of the wire electrode used, and a grooved roller at its free end. an electrode guide rod to which the grooved roller is removably attached and supported so as to be movable along its central axis and rotatable around the central axis; A servo feed device for processing feed and a servo rotation device for rotating the electrode guide rod about its central axis are provided.

[For production]

With the above configuration, at the start of machining 1, the wire electrode is hooked to the free end of the electrode guide rod having an electrode guide groove, or the wire electrode is hooked to the grooved roller having an electrode guide groove. If the guide rod is servo-feeded toward the workpiece in the central axis direction, and at the same time the electrode guide rod is rotated around its central axis, electrical discharge machining is performed using the wire electrode. When drilling a pilot hole, etc., two reciprocating wire electrodes are inserted into the drilled hole at the same time as machining is performed, so the two reciprocating wire electrodes are then used to perform normal contour machining. is possible.

〔Example〕

Hereinafter, details of the configuration of the present invention will be specifically explained with reference to the drawings.

Figures 1 to 5 show an embodiment of the reciprocating two-wire wire-cut electric discharge machining apparatus according to the present invention, in which the drilling of the prepared hole for machining and the setting of the wire electrode at the start of machining are sequentially performed automatically. FIG. 6 is an enlarged perspective view showing the main part of the tip of the electrode guide rod in the device of the above embodiment, and FIG. 7 is a diagram showing the wire electrode in the device of the above embodiment. FIG. 8 is an explanatory diagram of the automatic folding mechanism, and is an explanatory diagram showing the main parts of another form of the electrode guide rod.

In Figs. 1 to 5, 1 is a part of a wire-cut electrical discharge machining device that folds one wire electrode into two and performs machining with these two wire electrodes, and 2 is a A first arm or processing head, 3 is a second arm or processing head, and these are attached to a column or the like erected on the main body (bed) of the processing machine or on the side thereof. 4 is a wire electrode, 5 is a wire electrode supply roller housed in the first arm or processing head 2, 6, 6, 7 and 7 are guide rollers, 8 is a tension brake roller, 9 is a pinch roller, 10 is a A power supply roller, 11 is a winding tension capsun, 12 is a pinch roller, 13 is a wire electrode automatic folding mechanism, 13a is a folding guide roller, 13b is a motor for rotating the folding guide roller 13a, 14 is an electrode guide rod, 14a is a A grooved tip 15 is integrally attached to the free end of the electrode guide rod 14 and has a guide groove on its outer peripheral edge for guiding the wire electrode;
4 is slidably supported in the vertical direction in the figure, and is attached to the first arm or processing head 2 so as to be rotatable about the axis of the electrode guide rod 14, 16 is a motor, and 17 is a rotary disk. attached to the rotating shaft of the motor 16,
A pinion gear 18.18 is meshed with a crown gear formed on the upper surface of the rotary disk 15, and 18.18 is the rotary disk 1.
A feed roller 18 is attached to the top of the electrode guide rod 14 and is brought into contact with the electrode guide rod 14 to move the electrode guide rod 14 in the vertical direction in the figure. 20 is a workpiece.

Note that a power supply device that applies a voltage pulse for electrical discharge machining between the wire electrode 4 and the workpiece 20 via the power supply roller 10, a machining fluid jet nozzle for supplying machining fluid to the machining part, and the wire electrode A drive device for applying machining feed along the X-Y axis direction between the workpiece and the workpiece, a numerical control device for controlling the drive device, and the like are omitted in the figure.

In the first arm or machining head 2 of the wire-cut electrical discharge machining apparatus 1, there are a wire electrode supply roller 5, a power supply roller 10, a guide roller 6, a tension brake roller 8, a capstan 12, and others not shown. A wire electrode collecting roller and the like are built in, and a guide roller 7.7, a wire electrode automatic folding mechanism 13, etc. are built in the second arm or processing head 3.

The power supply roller 10 and the guide rollers 6, 7, and 7 facing the power supply roller 10 can be moved and adjusted in the left and right directions in the figure as necessary, so that they can be set at appropriate positions. It is constructed so that it can hold 4.

The electrode guide rod 14 is supported by a rotary disk 15 so as to be movable in the direction of its central axis (up and down in the figure), and by operating a motor 19, a suitable speed reduction mechanism and feed rollers 1B, L8 are activated. It is designed to be servo fed through the Further, the electrode guide rod 14 is attached to the rotary disk 15 with an appropriate rotation prevention mechanism such as a key and a keyway, so that although it is movable in the axial direction as described above, On the other hand, relative rotation is disabled, so that when the rotary disk 15 rotates, it rotates together with it.

A crown gear is formed on the upper edge of the rotary disk I5, and the crown gear meshes with a pinion gear 17 attached to the rotating shaft of the motor 16.
6, the rotary disk 15 is servo-rotated in a desired direction, and at the same time, the electrode guide rod 14 is also rotated around its central axis. Of course, the rotation is, for example, an angle of 180° to 270° in both positive and negative directions.
It may be a reciprocating rotation back and forth.

The grooved tip 14a provided at the tip of the electrode guide rod 14 has a guide groove 14a on its periphery for guiding the wire electrode 4, as shown in an enlarged view in FIG.
-1 is formed. The depth of the guide groove 14a-1 is shallower than the diameter of the wire electrode 4, so a part of the surface of the wire electrode is exposed from the guide groove 14a-1, thereby allowing the wire electrode 4 to be guided along the electrode guide rod 14. It is now possible to run the machine and perform electrical discharge machining. In addition,
One side 14a-2 on the tip side of the grooved tip 14a is the sixth
As shown in the figure, it is formed in a semicircular shape, and is designed to facilitate the wire electrode pulling operation by the wire electrode automatic folding mechanism 13, which will be explained in detail later with reference to FIG.

The reciprocating two-wire wire-cut electric discharge machining apparatus according to the present invention then drills a pilot hole in the workpiece 20 and automatically sets the two reciprocating wire electrodes in preparation for machining. will be explained with reference to FIGS. 1 to 5.

First, the electrode guide rod 14 is pulled upward as shown in FIG.
A constant distance is maintained between and 7 so that the electrode guide rod 14 can pass therethrough. At this point, the wire electrode 4 pulled out from the wire electrode supply roller 5 is
From brake roller 8 and guide roller 6 to capstan 1
1 and a pinch roller 12, and then wound around a wire electrode collection roller (not shown).

When the motor 19 is driven to rotate the feed rollers 1B and 1B and the electrode guide rod 14 is gradually moved downward, the wire electrode 4 is moved to the grooved tip attached to the tip of the guide rod 14. 14a, and is gradually pushed down with the wire electrode 4 captured in the guide groove 14a-1 (see FIG. 2).

That is, the electrode guide rod 14 passes between the guide roller 6 and the power supply roller 10 and extends downward, and at this time, the wire electrode 4 is passed from the wire electrode supply roller 5 through the brake roller 8 and the pinch roller 9. Forcibly withdraw it
, the wire electrodes 4 are stretched in a U-shape and are pushed downward while being updated and fed in the axial direction.

When the electrode guide rod 14 is moved further downward, its tip approaches the upper surface of the workpiece 20. At this point, a processing voltage pulse is applied between the workpiece 20 and the wire electrode 4 from a power supply device (not shown) via the power supply roller 10, and the motor 16 is alternately driven in reverse to rotate the rotary plate 15. This causes the electrode guide rod 14 to reciprocate around its central axis over a range of at least 180 degrees. In such a case, an electrical discharge is generated between the wire electrode and the workpiece, and the workpiece is gradually machined by the discharge erosion. Therefore, by continuing to slowly move the electrode guide rod 14 downward, the workpiece can be A pilot hole 20a is gradually formed in the workpiece 20.
(See Figure 3). Note that water or other machining fluid is supplied to the machining portion where the wire electrode 4 and the workpiece 20 are closely opposed to each other through a machining fluid jetting nozzle (not shown).

When the pilot hole 20a is bored in the workpiece 20 as described above, the electrode guide rod 14 passes through the pilot hole and extends further downward (see FIG. 4), and the grooved tip 1
When the lower end portion of 4a reaches the position of the folding guide roller 13a of the electrode automatic folding mechanism 13 provided in the second arm or processing head 3, the downward movement of the electrode guide rod 14 is stopped and the electrode automatically folds back. The folding mechanism 13 operates and the wire electrode 4 is delivered to the folding guide roller 13a. The structure and operation of this wire electrode automatic folding mechanism 13 can be substantially the same as that previously disclosed by the applicant in Japanese Patent Application No. 60-000391, etc., so please refer to FIG. 7 below. I'll explain the outline.

In FIG. 7, 13a is the wire electrode folding guide roller, 1
3b is a motor for rotating this, 13c is a slide table for moving the motor 13b in a direction perpendicular to the wire electrode 4 stretched over the grooved chip 14a, and 13d is equipped with the slide table 13c. 13e is a motor for moving the slide table 13c, and 13f is a feed screw attached to the rotating shaft of the motor 13e. Further, in the folding guide roller 13a, 13a-1 is a wire electrode guide groove formed along a line between the outer peripheral surface of the folding guide roller 13a and a plane perpendicular to the axis, and 13a-2 is a wire electrode guide groove formed in the guide groove 13a. 13a-3 is a cylindrical portion of the folded guide roller 13a, and 13a-4 is the tip of the folded guide roller 13a.

Thus, the half-moon shaped portion 14a-2 at the lower end portion of the grooved tip 14a of the electrode guide rod 14 is connected to the electrode automatic folding mechanism 1.
3, the downward movement of the electrode guide rod 14 is stopped, and at the same time, with the capstan 11 for moving the electrode stopped, move the electrode guide rod 14 slightly. When pulled upward, a loop of loose wire electrode 4 is formed at the tip of the grooved tip 14a.

At this time, by driving the motor 13e, the motor 1
3b is mounted on the slide table 13c toward the grooved tip 14a of the electrode guide rod 14,
At the same time, the motor 13b is driven to rotate the folding guide roller 13a.

In such a case, the tip portion 13a- of the folding guide roller 13a
4 enters the loop of the wire electrode 4 formed at the tip of the grooved tip 14a. When the capstan 11 is rotated and the wire electrode 4 is made to run at a predetermined speed when this insertion process is completed, the wire electrode 4 moves toward the grooved tip 14a of the folding guide roller 13a, and the brake roller 8 wire electrode 4 between and capstan 11
With the tension of the wire and the rotation of the folding guide roller 13a, the wire enters the spiral wire electrode introducing groove 13a-2 formed on the folding guide roller 13a, and further passes through the wire electrode introducing groove 13a-2. Electrode guide groove 13a-
It will lead you to 1.

Thus, the tip portion 13a-4 of the folded guide roller 13a is inserted into the loop of the wire electrode 4, or
is the wire electrode guide groove 13a-1 of the folded guide roller 13a.
When the electrode guide rod 14 is wound around the electrode guide rod 14, it is pulled upward (see FIG. 5). When the lifting operation of the electrode guide rod 14 is completed, the power supply roller 10 and the guide rollers 6 and 7 facing the power supply roller 10 are pulled up. and 7 are respectively moved toward the wire electrode 4, and the two reciprocating wire electrodes 4 are folded back by the folding guide roller 13a.
are brought close enough and even in close contact.

As described above, the wire electrode 4 passes from the wire electrode supply roller 5 through the guide roller 6 and the power supply roller 10, passes through the prepared hole 20a formed in the workpiece 20, and is housed in the second arm or processing head 3. After passing through the guide roller 7.7 section and being folded back by the folding guide roller 13a of the electrode automatic folding mechanism 13, the electrode passes through the guide roller 7.7 section again through the pilot hole 20a, and the guide roller 6, capstan 11 and pinch A wire electrode collection roller or collection (not shown) that passes through the roller 12 and is housed in the first arm or processing head 2, or is provided on the processing machine main body or the like to which the first arm or processing head is attached. It is stretched so that it can be collected in a container, etc.

As shown in FIG. 5, one wire electrode 4 is folded back into two wire electrodes by the wire electrode folding guide roller 13a, and the wire electrodes 4 folded back into two wire electrodes are connected to the power feeding roller 10. When the opposing guide rollers 6 and 7 are brought into contact with each other, a voltage pulse for machining is applied to the workpiece 20 and the wire electrode 4 from a power supply device (not shown) via the power supply roller 10. By supplying machining fluid to the machining part from a machining fluid jet nozzle (not shown) and applying a desired machining feed between the workpiece 20 and the wire electrode 4, wire cut electric discharge machining can be performed as usual. is being carried out.

In the above embodiment, a grooved tip 14a for guiding the wire electrode was provided at the tip of the electrode guide rod 14, but instead, a grooved roller 14b as shown in FIG. 8 was provided.
It is also possible to attach it detachably. That is, the grooved roller 14b has a guide groove 14b-1 formed on its outer periphery, which is shallower than the diameter of the wire electrode 4, and the wire electrode 4 is folded back to run along this groove. The grooved roller 14b is removably attached to a notch 14-1 formed in the electrode guide rod 14, and during processing, an electrode automatic folding mechanism provided in the second arm or processing rod 3 is used by appropriate means. It is constructed so that the entire roller can be taken over.

〔Effect of the invention〕

Since the present invention is structured like a ridge, when starting machining, the electrode guide rod with the wire electrode hooked to the grooved tip or grooved roller is directed toward the workpiece in the central axis direction. If electrical discharge machining is performed using the wire electrode while servo feeding and at the same time rotating the electrode guide rod around its central axis, the drilling of the prepared hole for machining will be done at the same time as the machining. Since the two reciprocating wire electrodes are inserted into the drilled hole, normal contour processing can be performed using the two reciprocating wire electrodes, and the reciprocating 2 wire electrode can be operated unattended for a long time. A wire-type wire-cut electrical discharge machining apparatus is provided.

Note that the present invention is not limited to the embodiment on ridges. That is, for example, various known means can be used to drive the electrode guide rod 14 in the central axis direction, rotate it around the central axis, etc.
The configuration can be adopted.

Alternatively, for example, a predetermined length portion on the tip side of the electrode guide rod 14 may be used as a pipe, and a wire electrode may be introduced into the interior from the side, pulled out from the tip, and guided axially along a guide groove formed on the outer surface of the pipe. It can be configured to run in reverse,
In order to create a loop of the wire electrode at the tip of the pipe when the wire electrode is delivered to the automatic folding mechanism, when the pipe is retreated, a fluid such as air is temporarily injected from inside the pipe, or at that time. An insertion auxiliary jig may be provided for guiding and holding the ring of the wire electrode and fitting the folding guide roller 13a to this ring. Therefore, the structure of the automatic wire electrode folding mechanism 13 is also the same as that of the above embodiment. It is not limited. Furthermore, the guide roller 6.
6.7.7 may be a 7-shaped or 0-shaped guide that can be opened and closed, or a die-shaped guide, or the wire electrode supply roller 5 may be provided on the side of the machine body to which the arm or processing head is attached, similar to the recovery device. These designs can be freely modified within the scope of the purpose of the present invention, and the present invention encompasses all such modified embodiments.

[Brief explanation of the drawing]

Figures 1 to 5 show an embodiment of the reciprocating two-wire wire cant electric discharge machining apparatus according to the present invention, in which the drilling of a pilot hole for machining at the start of machining and the setting of a wire electrode are sequentially performed automatically. Fig. 6 is an enlarged perspective view showing the main part of the tip of the electrode guide rod in the above embodiment device, and Fig. 7 is an explanatory diagram showing the wire electrode automatic process in the above embodiment device. FIG. 8 is an explanatory view of the folding mechanism, and is an explanatory view showing the main parts of another form of the electrode guide rod.

Claims (1)

[Scope of Claims] 1) In a reciprocating two-wire wire-cut electrical discharge machining device that performs machining by folding back one wire electrode so that two reciprocating wire electrodes closely face each other on a workpiece, an electrode guide rod having a guide groove shallower than the diameter of the wire electrode to be used at its free end and supported so as to be movable along its central axis and rotatably around its central axis; The above-mentioned reciprocating two-wire wire, characterized in that it is provided with: a servo feed device that processes and feeds the guide rod in the direction of its center axis; and a servo rotation device that rotates the electrode guide rod around its center axis. Cut electrical discharge machining equipment. 2) Diameter of the wire electrode used in a reciprocating two-wire wire-cut electrical discharge machining device that performs machining by folding one wire electrode so that two reciprocating wire electrodes closely face each other to the workpiece. A grooved roller having a shallower guide groove; and the grooved roller is detachably attached to the free end of the grooved roller, and is supported so as to be movable along its central axis and rotatably around its central axis. the electrode guide rod; a servo feed device that processes and feeds the electrode guide rod in the direction of its central axis; and a servo rotation device that rotates the electrode guide rod around its central axis. The above-mentioned reciprocating two-wire wire-cut electrical discharge machining device.