JPH0520212B2 - - Google Patents

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, it is possible to bring two reciprocating wire electrodes closer to a workpiece by folding back one wire electrode.
The present invention relates to an improvement of a reciprocating two-wire wire cut electrical discharge machining device that performs electrical discharge machining while running in opposing directions.

[Conventional technology]

The applicant previously filed Japanese Patent Application No. 59-260029,
No.-260030, Japanese Patent Application No. 60-000391, etc. disclose a wire-cut electric discharge machining device that performs machining by folding back one wire electrode so that two reciprocating wire electrodes closely face the workpiece. Disclosed.

With the above configuration, the machining part has two reciprocating
Since two wire electrodes are made to run in parallel, the machining gap formed between the workpiece and the workpiece is wider than when machining is performed with a single wire electrode as in the past, and the nozzle is inserted into the gap. etc., it is possible to easily supply a large amount of machining fluid, which increases the cooling effect and allows machining to be performed with a large current, improving machining efficiency. By running the electrodes in contact with each other, many advantages can be obtained, such as eliminating bending of the electrodes due to discharge pressure 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 a limit to the ability to carry out 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 problems, and its purpose is to perform the drilling work of a pilot hole for machining prior to machining in a reciprocating two-wire wire cut electric discharge machining device, and to perform this work. It is an object of the present invention to provide a device capable of simultaneously and automatically inserting two wire electrodes back and forth into a pilot hole.

[Means for solving problems]

In order to achieve the above object, the round trip 2 according to the present invention
In the first form of the wire-type wire cut electric discharge machining apparatus, a first arm or a machining head having wire electrode supply and collection means;
A recovery means provided on the first arm or processing head is configured to fold back one wire electrode supplied from the first arm or processing head, bring the two reciprocating wire electrodes into contact with or close to each other, and run in opposite directions. In a reciprocating two-wire wire cut electric discharge machining device, which has a second arm or a machining head equipped with an electrode return device to send back the reciprocating wire to a workpiece, and performs machining by placing two reciprocating wire electrodes in close opposition to a workpiece. There,
The free end has a guide groove shallower than the diameter of the wire electrode used, and is provided on the first arm or processing head and is movable toward the electrode return device provided on the second arm or processing head. and rotatably supported around its central axis, the wire electrode supplied from the wire electrode supply means is folded back from the guide groove at its free end, and is sent back to the recovery means while drilling a hole in the workpiece. , an electrode guide rod for passing the wire electrode over the electrode return device after completion of the drilling process, a servo feed device for processing and feeding the electrode guide rod in the direction of its central axis, and a servo feed device for rotating the electrode guide rod around its central axis. A device for moving the device is provided.

Further, in the second embodiment of the reciprocating two-wire wire cutting electric 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 having the groove at its free end. A roller is detachably attached to the electrode, and is provided on the first arm or the processing head, and is movable toward the electrode return device provided on the second arm or the processing head.
The wire electrode is rotatably supported around its central axis, and the wire electrode supplied from the wire electrode supply means is folded back from a grooved roller attached to the free end of the wire electrode, and is sent back to the collection means while drilling is performed on the workpiece. After the drilling process is completed, an electrode guide rod is used to pass the wire electrode around the electrode return device, a servo feed device is used to process and feed the electrode guide rod in the direction of its central axis, and and an electrode return device that removably supports a grooved roller attached to the tip of the electrode guide rod.

[Effect]

With the above configuration, at the start of processing,
The electrode guide rod having a wire electrode hooked to the free end portion having an electrode guide groove, or the electrode guide rod having a wire electrode hooked to the grooved roller having an electrode guide groove directed toward the workpiece. If electric discharge machining is performed using the wire electrode while servo feeding in the direction of the central axis and simultaneously rotating the electrode guide rod around the central axis, drilling of holes such as pilot holes for machining can be performed. At the same time as the two reciprocating wire electrodes are inserted into the drilled hole, normal contour processing can be subsequently performed using the two reciprocating wire electrodes.

〔Example〕

Hereinafter, the 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 work of drilling a pilot hole for machining and the work of setting a wire electrode at the start of machining are performed automatically in sequence. An explanatory diagram showing the process to be carried out step by step, 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 a diagram showing the automatic folding of the wire electrode in the above embodiment device. FIG. 8 is an explanatory view of the mechanism, showing the main parts of another type of electrode guide rod.

In Figs. 1 to 5, 1 is a part of a wire-cut electric discharge machining device in which one wire electrode is folded back to form two wire electrodes, and machining is performed using these two wire electrodes; An arm or processing head 1 and a second arm or processing head 3 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 the power supply roller, 1
1 is a winding tension capstan, 12 is a pinch roller, 13 is a wire electrode automatic folding mechanism, 13
a is a folding guide roller, 13b is a motor for rotating the folding guide roller 13a, 14 is an electrode guide rod, 14a is integrally attached to the free end of the electrode guide rod 14, and a wire electrode is attached to the outer peripheral edge thereof. A grooved tip 15 having a guide groove for guiding supports the electrode guide rod 14 so as to be slidable in the vertical direction in the figure, and is also attached to the first arm or the tip so as to be rotatable about the axis of the electrode guide rod 14. A rotary disk attached to the processing head 2, 16 a motor, 17
is attached to the rotating shaft of the motor 16 and is meshed with a crown gear formed on the upper surface of the rotary disk 15;
4 is brought into contact with a feed roller that moves the electrode guide rod 14 in the vertical direction in the figure; 19 is a motor that drives the feed rollers 18, 18 via an appropriate speed reduction mechanism; 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.

The wire electrode supply roller 5, the power supply roller 10, the guide roller 6, the tension brake roller 8, and the take-up tension capstan 11 are disposed in the first arm or machining head 2 of the wire cut electric discharge machining apparatus 1. Other wire electrode collection rollers (not shown) are built-in, and a second
Built-in the arm or processing head 3 are guide rollers 7, 7, a wire electrode automatic folding mechanism 13, and the like.

Note that the power supply roller 10, the guide roller 6 facing it, and the guide rollers 7, 7 can be set to appropriate positions by moving and adjusting them in the left and right directions in the figure, as necessary. It is configured to be able to hold the wire electrode 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 (in the vertical direction in the figure), and by operating a motor 19, the electrode guide rod 14 can be moved through appropriate deceleration and feed rollers 18, 18. It is designed to be fed by servo. 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 15, and the crown gear meshes with a pinion gear 17 attached to the rotating shaft of the motor 16. By driving the motor 16, the rotary disk 15 is rotated. is rotated in a desired direction, and together with this, the electrode guide rod 14 is also rotated around its central axis. Of course, the rotation may be a reciprocating rotation in the positive and negative directions, for example, at an angle of about 180° to 270°.

The grooved tip 14a provided at the tip of the electrode guide rod 14 has a guide groove 14a-1 on its periphery for guiding the wire electrode 4, as shown in an enlarged view in FIG. It is formed. The depth of the guide groove 14a-1 is shallower than the diameter of the wire electrode 4, and therefore a part of the surface of the wire electrode is exposed from the guide groove 14a-1, thereby guiding the wire electrode 4 along the electrode guide rod 14. Electrical discharge machining can be performed by running the machine with the machine running.
Note that one side 14 on the tip side of the grooved tip 14a
a-2 is formed into a semicircular shape as shown in FIG.
This facilitates the wire electrode pulling operation by the wire electrode automatic folding mechanism 13, which will be explained in detail with reference to FIG. 7 later.

Then, by using the reciprocating two-wire wire cutting electric discharge machining apparatus according to the present invention, a pilot hole for machining is made in the workpiece 20, and the two reciprocating wire electrodes are automatically set 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 interval is maintained so that the electrode guide rod 14 can pass through. At this point, the wire electrode 4 pulled out from the wire electrode supply roller 5 passes through the brake roller 8 and guide roller 6, winds up the tension capstan 11 and pinch roller 12, and winds up on the wire electrode collection roller (not shown). It is stretched so that it can be taken.

Then, the motor 19 is driven to feed the feed roller 1.
8 and 18 to gradually move the electrode guide rod 14 downward, the wire electrode 4 is hooked to the grooved tip 14a attached to the tip of the electrode guide rod 14, and the wire electrode 4 is hooked to the grooved tip 14a attached to the tip of the electrode guide rod 14, The wire electrode 4 is gradually pushed down while being captured in the inside (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 moved from the wire electrode supply roller 5 to the tension brake roller 8 and the pinch roller 9. The wire electrode 4 is forcibly pulled out through the wire, stretched in a U-shape, and pushed down while the wire electrode 4 is being renewed 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 machining voltage pulse is applied between the workpiece 20 and the wire electrode 4 via the power supply roller 10 from a power supply device (not shown), and the motor 1
6 is alternately reversely driven to rotate the rotary disk 15, thereby reciprocating the electrode guide rod 14 over a range of at least 180 degrees around its central axis. 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, so by continuing to slowly move the electrode guide rod 14 downward, Workpiece 2
A pilot hole 20a is gradually bored in the hole 0 (see FIG. 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 20a and extends further downward (the fourth
(see figure), the lower end portion of the grooved tip 14a is
When the electrode reaches 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 automatic folding mechanism 13 is activated. The wire electrode 4 is then delivered to the folding guide roller 13a. The structure and operation of this wire electrode automatic folding mechanism 13 can be similar to that previously disclosed by the applicant in Japanese Patent Application No. 60-000391, etc., so please refer to FIG. 7 below. I will briefly explain the outline.

In FIG. 7, 13a is the wire electrode folding guide roller, 13b is a motor for rotating this,
13c connects the motor 13b to the grooved tip 14.
13d is a base on which the slide table 13c is mounted;
e 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 common line between the outer peripheral surface of the folding guide roller 13a and one plane perpendicular to the axis;
13a-3 is a spiral wire electrode introduction groove connected to the guide groove 13a-1, and 13a-3 is the folded guide roller 1.
The cylindrical portion 3a, 13a-4, is the tip of the folded guide roller 13a.

Therefore, the grooved tip 14 of the electrode guide rod 14
The half-moon-shaped portion 14a-2 at the lower end portion of a reaches the position of the folding guide roller 13a of the automatic electrode folding mechanism 13, and the downward movement of the electrode guide rod 14 is stopped, and at the same time, the electrode is caused to travel. When the electrode guide rod 14 is pulled upward slightly with the capstan 11 stopped, a loose ring of the wire electrode 4 is formed at the tip of the grooved tip 14a.

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

In this case, the tip portion 13a-4 of the folding guide roller 13a enters the loop of the wire electrode 4 formed at the tip portion of the grooved tip 14a. When the winding tension capstan 11 is rotated to make the wire electrode 4 travel at a predetermined speed after this insertion process is completed, the wire electrode 4 is directed toward the grooved tip 14a of the folding guide roller 13a. With the movement, the tension of the wire electrode 4 between the brake roller 8 and the capstan 11, and the rotation of the folding guide roller 13a, the folding guide roller 13a
A spiral wire electrode introducing groove 13a-
2, and further into the wire electrode introducing groove 13a.
-2 and is guided to the wire electrode guide groove 13a-1.

Therefore, the tip portion 13 of the folding guide roller 13a
When a-4 is inserted into the loop of the wire electrode 4, or when the wire electrode 4 is further wound around the wire electrode guide groove 13a-1 of the folded guide roller 13a, the electrode guide rod 14 is pulled upward (see FIG. reference),
When the lifting operation of the electrode guide rod 14 is completed, the power supply roller 10 and the guide rollers 6 and 7 opposing thereto are moved toward the wire electrode 4, and the folding guide roller 13a is moved toward the wire electrode 4. Round trip 2
The book wire electrodes 4 are brought close enough together 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 rollers 7, 7 section and being folded back by the folding guide roller 13a of the wire electrode automatic folding mechanism 13, the wire passes through the guide rollers 7, 7 section again through the pilot hole 20a, and then passes through the guide roller 6 and the winding tension. It passes through the capstan 11 and the pinch roller 12 and is housed in the first arm or processing head 2, or is provided in the processing machine body, etc. to which the first arm or processing head is attached, and is not shown. The wire electrode is stretched so that it can be collected by a collection roller, a collection container, or the like.

As shown in FIG. 5, one wire electrode 4 is folded back into two by the wire electrode folding guide roller 13a, and this folded wire electrode 4 is folded back into two wires by the power supply roller. 10 and the opposing guide roller 6 and guide rollers 7 and 7 are brought into contact with each other, and a power supply device (not shown) supplies power to the workpiece 20 and the wire electrode 4 via the power supply roller 10 for processing. While applying a voltage pulse and supplying machining fluid to the machining portion from a machining fluid jet nozzle (not shown), the workpiece 20 is
By applying a desired machining feed between the wire electrode 4 and the wire electrode 4, wire cut electric discharge machining is performed as usual.

In addition, in the above embodiment, the electrode guide rod 14
Although a grooved tip 14a is provided at the tip of the wire electrode for guiding the wire electrode, a grooved roller 14b as shown in FIG. 8 may be detachably attached instead. That is, a guide groove 14b-1 shallower than the diameter of the wire electrode 4 is formed on the outer periphery of the grooved roller 14b, and the wire electrode 4 is folded back so as to run along this groove. The grooved roller 14b is the electrode guide rod 14.
The wire electrode is detachably attached to a notch 14-1 formed in the wire, and is configured to be taken up along with the roller by an appropriate means during processing by the wire electrode automatic folding mechanism 13 provided in the second arm or the processing head 3. It is something that

〔Effect of the invention〕

Since the present invention is constructed as described above, at the start of machining, the electrode guide rod, on which the wire electrode is hooked to the grooved chip or the grooved roller, is directed toward the workpiece and the central axis If electrical discharge machining is performed using the wire electrode while servo feeding the wire in the direction and simultaneously rotating the electrode guide rod around its central axis, drilling of holes such as pilot holes for machining will be performed. At the same time, the two reciprocating wire electrodes are inserted into the opened hole, so normal contouring can be performed using the two reciprocating wire electrodes, and long-term unmanned operation is possible. A reciprocating two-wire wire cut electric discharge machining apparatus is provided.

Note that the present invention is not limited to the embodiments described above. That is, for example, various known means and configurations can be employed as a method for driving the electrode guide rod 14 in the direction of the central axis, a method for rotating the electrode guide rod 14 around the central axis, and the like. 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. In order to create a loop of the wire electrode at the tip of the pipe when the wire electrode is transferred to the automatic folding mechanism, fluid such as air is temporarily injected from inside the pipe when the pipe is retreated. In addition, a guide roller 13 is used to guide and hold the ring of the wire electrode at that time, and to fold back this ring.
An insertion auxiliary jig may be provided for fitting the electrodes 1 and 2, and therefore, the structure of the wire electrode automatic folding mechanism 13 is not limited to the above embodiment. Furthermore, the guide rollers 6, 6, 7, 7 may be V-shaped or U-shaped or dice-shaped guides that can be opened and closed, or the wire electrode supply roller 5 may be equipped with an arm or a processing head similar to the recovery device. It may also be installed on the side of the machine body,
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-cut electric discharge machining apparatus according to the present invention, in which the work of drilling a pilot hole for machining and the work of setting a wire electrode at the start of machining are performed automatically in sequence. An explanatory diagram showing the process to be carried out step by step, 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 a diagram showing the automatic folding of the wire electrode in the above embodiment device. FIG. 8 is an explanatory view of the mechanism, showing the main parts of another type of electrode guide rod. 1... wire cut electric discharge machining device, 2... first
arm or processing head, 3... second arm or processing head, 4... wire electrode, 5... wire electrode supply roller, 6, 6, 7, 7... guide roller, 8... tension brake roller , 9... pinch roller, 10... power supply roller, 11... winding tension capstan, 12... pinch roller, 13... wire electrode automatic folding mechanism, 13a...
...Folding guide roller, 13b...Motor, 13c...
...Slide table, 13d...Base, 13e...
...Motor, 13f...Feed screw, 13a-1...
Wire electrode guide groove, 13a-2... Wire electrode introduction groove, 13a-3... Cylindrical part, 13a-4... Tip part, 14... Electrode guide rod, 14a... Grooved tip, 14a-1... Guide groove, 14a-2... Half-moon shaped portion, 14b... Grooved roller, 14b-1...
Guide groove, 15...Rotary disk, 16...Motor, 17
...Pinion gear, 18,18...Feed roller,
19...Motor, 20...Workpiece.

Claims (1)

[Scope of Claims] 1. A first arm or processing head equipped with wire electrode supply and collection means, and one wire electrode supplied from the first arm or processing head, folded back to form two reciprocating wire electrodes. a second arm or processing head that is equipped with an electrode return device that causes the wire electrodes to contact or be brought close to each other and run in the opposite direction, and return the wire electrodes to the recovery means provided in the first arm or the processing head; In a reciprocating two-wire wire cut electrical discharge machining device that processes a workpiece by placing two reciprocating wire electrodes close to each other in opposition, the free end of the reciprocating wire cutting electric discharge machining device has a guide groove shallower than the diameter of the electrode of the wire used. provided on the first arm or processing head and movable toward an electrode return device provided on the second arm or processing head;
The wire electrode is rotatably supported around its central axis, and the wire electrode supplied from the wire electrode supply means is folded back from the guide groove at its free end, and while being sent back to the recovery means, the workpiece is perforated. An electrode guide rod for passing the wire electrode over the electrode return device after processing, a servo feed device for processing and feeding the electrode guide rod in the direction of its central axis, and a servo feed device for rotating the electrode guide rod around its central axis. The above-mentioned reciprocating two-wire wire-cut electrical discharge machining device, characterized in that it is provided with the following: 2. A first arm or processing head equipped with wire electrode supply and collection means and one wire electrode supplied from the first arm or processing head are folded back and the two reciprocating wire electrodes are brought into contact with each other or A second arm or a processing head is provided with an electrode return device that moves the electrode in the opposite direction and sends the electrode back to the recovery means provided on the first arm or the processing head, and the second arm or processing head is provided with In a reciprocating two-wire wire cutting electric discharge machining device that performs machining by placing two wire electrodes close to each other, a grooved roller having a guide groove shallower than the diameter of the wire electrode used, and a grooved roller having the above-mentioned groove on its free end are used. A roller is detachably attached to the first arm or the processing head, and is movable toward the electrode return device provided on the second arm or the processing head, and is rotatable about its central axis. The wire electrode supplied from the wire electrode supplying means is folded back from the grooved roller attached to the free end thereof, and the wire electrode is fed back to the collection means, while perforating the workpiece.
An electrode guide rod for passing the wire electrode over the electrode return device after completion of the drilling process; a servo feed device for processing and feeding the electrode guide rod in the direction of its central axis; and a servo feed device for rotating the electrode guide rod around its central axis. and an electrode return device that removably supports a grooved roller attached to the tip of the electrode guide rod.