JPS60131121A - Method and device for wire-cut electric discharge machining - Google Patents

Abstract

PURPOSE:To set a wire electrode quickly by performing automatically formation of the machining start hole and threading of the wire through utilization of an electrode mounting chuck in the form of a thin tube, which can rotate and rise and fall freely. CONSTITUTION:In this wire-cut discharge machining device, an electrode 1 in the form of a thin tube is installed on a mounting chuck 25 for this thin tubed electrode, and a wire electrode 2 is threaded through this thin tubed electrode 1. The wire electrode 2 is grasped by a holder 22 in such a way as fed in the axial direction together with the thin tubed electrode 1. Then the tip of the wire electrode 2 is cut off so as to be in a plane with the tip of the thin tubed electrode 1, and the machining liquid is supplied to be center hole 1a in the electrode 1. Now pulsed voltage is impressed with the tips of electrodes 1, 2 fronting to the work to be machined 39, and necessary feed is given by a hydraulic cylinder 32 while the electrode 1 is rotated by a motor 29a. Thus small hole for insertion of electrode is machined. Then the wire electrode 2 is released from grasp to be sent out to a wire electrode receipt device so as to provide stretching-over, and the electrode 1 is drawn out from this small hole.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a wire-cut electrical discharge machining method in which machining is started by automatically forming a crab start hole and inserting a wire electrode in a wire-cut electrical discharge machining apparatus. and its apparatus.

Wire-cut electrical discharge machining equipment does not require the production of electrodes corresponding to the machining shape each time it is machined, unlike regular electrical discharge machining equipment, and with the development of numerical control equipment (NC equipment), long-term unmanned operation is possible. Due to certain reasons, it is now widely used.

When contouring a cutting die or the like using a wire-cut electrical discharge machining device, first a hole for passing the wire electrode through the workpiece is formed, and the wire electrode is inserted into the hole for passing the electrode. At the same time, the wire electrode is usually stretched in a straight line with an appropriate tension between a pair of electrode guides provided at the ends of two arms, and during processing, the wire electrode and the workpiece are A machining fluid is supplied between the two, and intermittent voltage pulses are applied between the two to create a discharge, and machining feed is applied to the wire electrode or the workpiece using a numerical control device, thereby machining the desired contour. This is what we do.

However, it is extremely difficult to form a straight and uncurved hole for electrode insertion in a thick workpiece, and the machining process requires a drilling machine or jig holer that is separate from the wire-cut electric discharge machining equipment. If the drilling is performed using a mechanical drilling device such as , or a drilling device using electrical machining such as electric discharge or electrolytic processing, positioning of the workpiece must be performed twice, once during drilling and once during electric discharge machining. The problem was that it wasn't as long as it needed to be, and it took time. Furthermore,
・Twier electrodes have a diameter of 111 II or less, usually 0.
The wire is extremely thin, taking approximately 0.05 to 0.3 ms+, and is accurately inserted into the electrode insertion hole formed in the workpiece before the start of processing, and stretched in a straight line between a pair of guides. There was also the problem that it was extremely difficult to speak the language.

In order to solve the above problems, it has been proposed that the hole for inserting the wire electrode be drilled by machining or electrical machining while the workpiece is positioned and attached to a wire-cut electric discharge machine (for example, , Japanese Patent Publication No. 48-33493
(Japanese Utility Model Publication No. 51-31195, etc.) Before the start of machining, a wire-cut electric discharge machining head is attached to the machining head of wire-cut electric discharge machining, or to a drilling machine that can be retracted and taken out. A hole for inserting the wire electrode into the workpiece is made using a tool or a capillary electrode for electrical machining, and then the tool or the rod-shaped hollow capillary electrode is retracted from the machining part. Then, the wire electrode supply head is guided to the processing part, and the wire electrode is sent out and inserted into the electrode insertion hole machined in the workpiece, and the tip of the penetrating wire electrode is engaged with a recovery device so that it can be recovered. When the wire electrode is stretched in a straight line by a pair of guides on both sides of the workpiece, a relative feed is applied between the wire electrode and the workpiece to start electrical discharge machining. A wire-cut electrical discharge machining device equipped with an automatic wire electrode insertion device was developed.

In the above case, it is preferable that the pair of guides provided on both sides of the workpiece be provided close to the workpiece, so that the wire electrode does not pass through the electrode insertion hole of the workpiece. As for the guide on the side that comes out, a conventional die guide or the like may be used as is, or in the case of a V-groove sliding contact guide, the guide may be retracted slightly or be configured to open and close. V? Although it can be used if the configuration allows the holding piece for m to be retracted,
For the guide on the electrode supply side, the distance for retraction of the die guide, the groove guide, and its holding piece, etc. is determined depending on the position to allow the use of a tool for drilling holes for electrode insertion and the use of thin tube-shaped electrodes. Because it is necessary to configure the V-groove guide or compound die guide to a large degree of opening/closing, even if positioning is done with a high degree of precision, there may be problems with the properties of the wire electrode, such as curvature, curl, shape of the cut end, etc. Of course, the wire electrode is sent out with its tip free while contacting a guide, etc., the inner circumferential wall of the electrode insertion hole, and other inclusions such as a contact energizing pin. Therefore, the automatic wire electrode insertion device described above not only requires complicated work for insertion, but also the operation of inserting the wire electrode into the electrode insertion hole or the operation of inserting it through the guide is not always performed well. There was a problem.

That is, in the above device, the formation of the insertion hole and the insertion of the wire electrode are divided into two steps, and the processing of the inner peripheral wall surface of the insertion hole by the outer peripheral wall surface portion of the thin tube-shaped electrode causes the processed surface to be roughened. Even if the diameter of the insertion hole is small and is carried out fairly well, the diameter of the insertion hole is small, about 1 φ or less at most, and if the thickness of the workpiece is several tens of iris or more, the wire Inserting the electrode is not easy, so even if the electrode insertion hole is successfully drilled, the wire electrode must be inserted into the hole and the tip of the wire electrode must be inserted into a small guide die or other guide. Reliable insertion or positioning was quite difficult.

Furthermore, since the drill tool and the device for moving the thin tubular electrode up and down are attached to the upper arm or the machining head, there is a problem that the overall upper structure of the wire-cut electric discharge machining apparatus becomes large. There was a point.

The present invention has been developed from a paper perspective, and its purpose is to work with thick workpieces, workpieces made of hardened steel, cemented carbide, etc. , it is possible to form a pore for electrode insertion in a short time, and the insertion of four electrodes into the formed pore for electrode insertion is substantially simultaneous with the processing and formation of the pore for electrode insertion. By performing the process progressively, the wire can be inserted reliably, and the wire is fed out from the tip of the thin tubular electrode that has been formed by processing the electrode insertion hole and penetrated to the other side of the workpiece. Since the tip of the electrode only needs to pass through a predetermined position relative to the guide, energizing device, and tensile force applying and collecting means, this method is much more convenient than conventional electrodes that require insertion through a small hole. This is relatively easy, and therefore, even if the guide on the other side of the workpiece is a small guide die, the wire electrode can be inserted reliably, and the wire electrode can be inserted in a straight line using a pair of guides. It is an object of the present invention to provide a wire-cut electric discharge machining method and apparatus, which enables highly accurate automatic machining because the wire can be stretched over the wire, and furthermore, the entire apparatus can be configured compactly.

The above purpose is to attach a capillary electrode to a chuck that is rotatable and movable up and down in a wire cutter I/electrical discharge machining device, to insert a wire electrode into the capillary electrode, and to attach the chuck to the chuck. The wire electrode is held so as to be axially fed together with the thin tubular electrode by a clamp provided on the supporting member, and then the tip of the wire electrode is placed on substantially the same plane as the tip of the thin tubular electrode. 2. Apply a voltage pulse with the tips of the capillary electrode and the wire electrode facing the workpiece, and cut the capillary electrode to While rotating it, a processing feed is applied to it to process and form a pore for electrode insertion,
After completing the penetrating process of the electrode insertion hole, the rotation of the tubular electrode and the power supply are stopped, the grip on the wire electrode is released, and the wire electrode is sent to the twist electrode take-up device. This is accomplished by pulling out the tubular electrode from the electrode insertion hole after stretching it.

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

FIG. 1 is an explanatory diagram showing a state in which a wire-cut electric discharge machining apparatus according to the present invention is machining a hole for inserting an electrode into a workpiece, and FIG. An explanatory diagram showing the state in which the insertion hole has been machined and the wire electrode has been inserted. Figure 3 is an explanatory diagram showing the state when wire cut electric discharge machining has started. Figure 4 is the machining liquid nozzle for opening and closing. It is an enlarged sectional view of a unit part.

In FIGS. 1, 2, 3, and 4, ■ indicates a wire electrode 2 having a diameter of approximately 0.05 to 0.4 is inserted into the inside thereof;
A thin tubular electrode having a predetermined length and having a hole 1a through which the machining fluid can be passed and sprayed, 3.4 is an open/close type machining fluid nozzle unit, 3a and 4a are split nozzles, and 3b and 4b are Seal member, 4C is machining fluid supply hole, 5
．． 6 is a cutter operated by a solenoid (not shown);
7 is an electrode support, 8 is a V-shaped electrode guide, 9 is a spring, 1o and 1] are hydraulic cylinders that open and close the opening/closing type machining liquid nozzle unit 3.4, 12 is a lower arm 13
I4 is the nozzle body attached to the nozzle device, 15
is a nozzle, work 6 is a bag nand, 17 is a die guide, 17
a is a guide holder, I8 and I9 are power feeding pins that can move forward and backward, 2o is a spring provided as necessary, 21 is a rubber valve, and 22 is a capillary electrode mounting chuck 25 consisting of a stem 23 and a tightening nut 24. 22a is a machining fluid supply hole formed in the stem holder 22, 27 is an anvil attached to the upper end of the stem holder 22, and 2B is the stem holder rotatably held via a bearing 26. An adjustable wire electrode fixing clamp screw 28A is provided facing the anvil 27; 29a is a motor; 29a is attached to the stem holder 22;
The motor has a gear 3o attached to it meshing with a gear 3I attached to a stem 23, and 32 is held on a required fixed part such as the upper arm of the wire cant electric discharge machine or the upper machining head held on the upper arm. A hydraulic cylinder 33 moves the stem holder 22 up and down with respect to a table (not shown) for mounting the workpiece, and 33 acts as a brake roller when the motor is stopped or rotating at a predetermined speed. 34 is a pinch roller which acts as a capstan when the is stopped or rotating under control such as sequence control;
35 is a capstan for taking up the wire electrode and applying tension; 36 is a pinch roller; 37 is an O'J song; 38 is a current-carrying shoe for supplying power to the capillary electrode 1; 39 is a workpiece;
40 is a rubber valve.

Thus, the capillary electrode l is connected to the stem 23 and the tightening naso 1-2.
The capillary electrode 1 is detachably attached to a chuck 25 for attaching a capillary electrode, which is made up of a tightening nut 2, when the capillary electrode 1 is worn out due to the machining of the electrode insertion hole.
The device is preferably configured to be an automatic electrode exchange type so that the worn out capillary electrode 1 can be reattached or replaced with a new capillary electrode 1 by loosening the cap 4.

The stem 23 has a hair ring 26 inside the stem holder 22.
The stem holder 22 is rotatably held through the stem holder 22, and is configured to rotate around its axis by the rotation of a motor 29 attached to the stem holder 22. Therefore, as the motor 29 rotates, the thin tubular electrode 1 is rotated about its axis.

The stem holder 22 is configured to be moved vertically relative to a fixed workpiece 39 by the action of a hydraulic cylinder 32 that supports the stem holder 22.

The opening/closing type machining fluid nozzle unit 3.4 includes split nozzles 3a, 4a, seal members 3b, 4b, and machining fluid supply holes 4.
0, etc., and is configured to open and close in the diametrical direction by the action of hydraulic cylinders 10 and 11. Further, an electrode retainer 7 configured to act on the elastic force of a spring 9 is placed in the central portion of the interior of the nozzle unit 3, and an electrode retainer 7, which is configured to act on the electrode retainer 7 of the other nozzle unit (4), is An electrode guide having a V-shaped cross section is attached to determine the position of the wire electrode 1 above the workpiece 39 during wire cut electrical discharge machining, and to hold the wire electrode 1 in a straight line.

The nozzle body 14 is attached to a flange 14a and a liquid reservoir chamber 14b.
, a wire electrode insertion hole 14C and a machining fluid supply hole 14d.
and the bag pads 16 are attached one after another.

After that, the nozzle device 12 can be removed from the flange 14a.
A mounting (not shown) is attached to the lower arm 13 by means of a pol[.

Thus, in the Wight Casso I-electrical discharge machining apparatus according to the present invention, the process of forming an electrode insertion hole for passing the wire electrode 2 through the workpiece 39 and the step of taking the wire electrode after forming the hole are performed. The process from reaching the device to engagement and then machining the workpiece 39 by wire-cut electrical discharge machining will be described.

As shown in FIG. 1, when forming an electrode insertion hole through which the wire electrode 2 is inserted into the workpiece 39, the pre-kissing roller and capstan 33 acts as a capstan, and the hole of the thin tubular electrode l is formed. A wire electrode 2 is inserted into la.

When the wire electrode 2 advances through the hole la of the capillary electrode 1 and its tip protrudes a predetermined length from the tip of the capstan 33, the wire electrode 2 is stopped, and
Clamp screw 2 provided at the upper end of the stem holder 22
8 is operated by a motor 28A to grip the wire electrode 2 so as to be sent in the axial direction by the movement of the holder 22 together with the capillary electrode 1, and at this time, the tip of the capillary electrode 1 is at the position of the cutters 5 and 6. If there is a discrepancy, for example, the wire electrode 2 is located above the capillary electrode, the hydraulic cylinder 32 is operated to make the adjustment match, and then the cutters 5 and 6 are operated by a solenoid (not shown), and the wire electrode 2 is connected to the capillary electrode. After cutting the nozzle unit 3.4 so that it is approximately flush with the tip of the electrode 1, the nozzle unit 3.4 is opened as shown in the figure, and the electrode 1
Start hole machining is possible by downward feed. On the other hand, in the workpiece 39, the position of the electrode insertion hole for starting machining is predetermined by marking etc.
A numerical control device (not shown) or the like is used to send the material through a processing table and position it to include a predetermined position.

The above is a case where when the thin tubular electrode 1 is replaced due to wear or the like or is newly attached to the chuck 25, the operation is started with the tip of the wire electrode 2 not reaching the base position of the electrode 1. When replacing the electrode 1, etc., the wire electrode 2 can be manually inserted into the electrode 1, and then the electrode 1 can be attached to the chuck 25, and in many cases, , with the wire electrode 2 cut at the tip of the electrode 1 on the supply side by the cutters 5 and 6 at the end of the previous wire cut electrical discharge machining,
Since the device is in a kind of standby state for the next processing operation, in such a case, the operation and process of inserting the wire electrode 2 into the electrode 1 is said to have been completed.

Voltage pulses for electrical discharge machining are supplied from a power supply circuit (not shown) to the capillary electrode 1 via the current shoe 38 and to the wire electrode 2 via the clamp screw 28 as necessary. At the same time, the tubular electrode 1 is given rotational motion by a motor 29 and downward movement by a hydraulic cylinder 32 via a stem holder 22 and a stem 23, and the same machining as that for wire cant electric discharge machining is normally performed. While the liquid is supplied from the hole 1a of the capillary electrode 1 to the processing portion of the workpiece 39, the electrode insertion hole is processed.

The processing of the electrode insertion hole in the workpiece 39 by the thin tubular electrode 1 is performed in a special manner, for example, except that the wire electrode 2 is inserted into the electrode 1 and the electrode 1 is rotated. This is performed by high-speed machining using deep hole electric discharge machining, which is described in detail in Japanese Patent Publication No. 56-69033, and at least 10 to 20 kg is
/c+J or above, the machining fluid is supplied under pressure, and preferably, although not shown, constant speed or servo feed is applied by the cylinder 32 while applying ultrasonic vibration to the thin tubular electrode 1 as described in the above publication. In this way, by spraying high-pressure machining fluid, rotating the electrode once, and applying vibration, it is possible to machine deep holes that could not be processed smoothly in the past, such as hardened steel and cemented carbide. Even in the thick workpiece 39, straight and uncurved electrode insertion holes can be formed in a short time.

In addition, when processing this electrode insertion hole, the wire electrode 2
Of course, when some electrical discharge machining power source is connected to the wire electrode 2, even if no power source is connected, the tip of the wire electrode 2 may wear out due to being in some kind of contact with the thin tubular electrode 1. Therefore, if the wear and retraction length of the tip of the wire electrode 2 with respect to the tip of the capillary electrode 1 reaches, for example, about several tuna or more, temporarily clamp the clamp screw 28 during the drilling process. The wire electrode 1 is released by the capstan 33 and the pinch roller 34.
It is preferable to send out the wire electrode 2 and correct it so that its tip is near the tip of the thin tubular electrode 1, since this will ensure that the wire electrode 2 can be inserted into the guide etc. thereafter.

When an electrode insertion hole through which the wire electrode 2 is inserted is formed in the workpiece 39, the motor 28A is activated to release the wire electrode from the clamp screw 28, and the tip of the thin tubular electrode 1 is released. The tip of the wire electrode 2, which is nearby and has already passed through the electrode insertion hole along with the tip of the electrode 1, is sent out toward the nozzle device 12 by the capstan action of the brake roller/capstan 33.
After being inserted and captured by the die guide 17, the guide holder 1
When the pinch roller 3G passes through the hole 17b of 7a, passes through the rubber valve 2I, and reaches the wire electrode take-up device consisting of the capstan 35 and others, which the pinch roller 3G approaches and separates from, and is secured, the wire is forcibly removed from the tip of the wire electrode 1. Then, they are collected in a wire electrode collection box (not shown) provided in the head of the wire-cut electric discharge machining apparatus main body.

When the wire electrode 2 is taken up by the take-up device as described above, the motor 29 is stopped and the thin tubular electrode 1 is removed.
The rotational movement of the hydraulic cylinder 3 is stopped, and the hydraulic cylinder 3
2 operates to move the stem holder 22 upwards and move the thin tubular electrode 1 upwards, and accordingly, the opening/closing type machining fluid nozzle UNISO 3.4 is closed by the action of the hydraulic cylinders 10 and 11. The wire electrode 2 is movably held down by the electrode presser 7 of the V-shaped electrode guide ``8'' inside the opening/closing type machining liquid nozzle unit 3.4. Power supply pin 18
Voltage pulses for electrical discharge machining are supplied from
Wire-cut electric discharge machining is performed while the machining fluid supplied from the wafer is supplied to the machining portion of the workpiece 39.

It should be noted that during electrical machining, the current-carrying pins, guides, etc. reach a considerable temperature due to electric discharge machining current, friction, and the like. However, in the wire cut electric discharge machining apparatus according to the present invention,
The power supply bottles 18, 19, die guide 17, etc. inside the nostle main body 14 are sufficiently cooled by the processing liquid passing through the liquid reservoir chamber 14b, so that they can withstand long-time operation.

In addition, if the thin tubular electrode 1 is worn out and its length becomes equal to or less than the workpiece 39 to be machined, the wire electrode 2
is replaced by cutting it at the tip of electrode 1, but when replacing electrode 1 manually, chuck 2
All you have to do is pass the wire electrode 2 that is hanging down up to 5 points through the new electrode 1, but this is extremely difficult if the electrode 1 is replaced automatically. There is a means for reversing the capstan 33 to return the capstan 33 to near the base of the stem yoke, then removing a new tubular electrode 1, feeding out the wire electrode 2, and passing it through to the tip of the electrode 1. Of course it will be accepted.

In addition, the wire electrode 2 is connected to the guide 17, the power supply bin I8.19,
rubber valve 21, capstan 35 and pinch roller 36,
Or, if insertion or centration fails at a further point such as an electrode pulling device, for example, the tubular electrode 1 is once pulled up to the position shown in FIG. 3, and the wire electrode 2 is cut at the tip of the electrode 1. Next, the wire electrode 2 that has been inserted up to the workpiece is pulled out manually or with a robot hand and discarded, and the wire electrode 2 is clamped to the holder 22 and lowered to the position shown in FIG. The operation is such that the clamp is released and the insertion and setting of the wire electrode 2 by feeding is attempted again.

Since the present invention is configured as on paper, when the wire cut electrical discharge machining method and apparatus according to the present invention are used,
Even if the workpiece is thick or hardened, it is possible to form a straight electrode insertion hole in a short time through which the wire electrode can be easily passed. The insertion of the wire electrode into the general hole is already done at the same time as the formation of the electrode insertion hole, so the tip of the wire electrode is positioned and inserted into the guide or electrode take-up device after the wire is inserted. It is sufficient to perform the operation so that the engagement occurs, and the probability of success in automatically inserting and setting the wire electrode is increased. Furthermore, even if the guide on the other side of the workpiece is a small guide die or the like, the wire electrode can be inserted with high probability, and the wire electrode can be stretched in a straight line by a pair of guides. This makes it possible to perform automatic processing with high precision, and furthermore, the entire device can be configured compactly.

Note that the present invention is not limited to the embodiments on paper. That is, for example, in this embodiment, the tubular electrode was configured to be moved up and down by a hydraulic cylinder via a stem holder, but it may also be configured to be moved up and down by a motor via a gear. Also, a known power supply method can be used to supply power to the capillary electrode and the wire electrode. In addition, machining fluid is supplied to the open/close type machining fluid nozzle unit during wire-cut electrical discharge machining by sandwiching and sealing the tip of the tubular electrode 1 with seal members 3b and 4b without using the hole 4c. Alternatively, the power supply pin or power supply roller to the wire electrode may be provided on the upper side of the workpiece, and the guide 8.17, power supply pin 18.19, etc. It can be installed externally to make it easy to open and close, advance and retreat, etc., and as a guide 8.17, for example,
No. 81234, No. 5B-194952, or No. 5B
Not only can the composite guide described in Japanese Patent Application No. 58-4094 be used as a machining fluid injection nozzle, but it can also be used as a machining fluid injection nozzle.
No. 9, No. 5B-4095Q or No. 58-70506
It is possible to use various configurations as described in No. 1, etc., and when machining the electrode insertion hole as the canister 1 and hole with the capillary electrode, the above-mentioned Various modifications are possible, such as providing a guide for guiding the position of the thin tubular electrode so that it can move forward and backward to prevent bending of the pores formed in a thick workpiece. The present invention can also be applied to a wire cutter electric discharge machine of a type in which a reversed wire electrode is fed from the bottom to the top for renewal. In addition, the position and mounting method of the die, the method of supplying the processed wave, the method of collecting the wire electrode, etc. can be freely changed within the scope of the purpose of the present invention, and the present invention does not cover these changes. It encompasses all of the above.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram showing a state in which an electrode insertion hole for inserting a wire electrode into a workpiece is being processed by an automatic wire threading device in a wire cut electric discharge device according to the present invention. Figure 2 is an explanatory diagram showing the state in which the electrode insertion hole has been machined and a wire electrode has been inserted, and Figure 3 is an explanatory diagram showing the state when wire cut electric discharge machining has started. , FIG. 4 is an enlarged sectional view of the opening/closing machining liquid nozzle unit. i-':-----
−−1−−−−−−−−−−・−・−Wire electrode'3.
4------------------- One open/close type machining liquid nozzle unit 5.6---------- One cutter 7-- −−−−−−−−−−−−Electrode presser 8−・−−−−−−−−−−−−−−−−−−V-shaped electrode guide 9.20−−−−−−−− ---1.-Spring 10.11.32--Hydraulic cylinder 1
2−−−−−−−−−−−−−・−−−−−−Nozzle device + 4 ':' −−−−−−−−−−−−−−−−−
Nozzle body 15-----------11--
-----Nozzle 16------------
−One bag of Nantes +7−−−−−−−・−・−−−−−・
~Dice guide 2■, 40--
Rubber valve 25-----1・-----1----
・-Channel 26 for attaching capillary electrodes-------
−−−−−−−−− Hair ring 27−・−−−−−−
1---------Anvil 28------
----------- Clamp screw 28A, 29-
−−−−〜−−=−Motor 33−−−−−−−−−−−
-------- Brake roller and cabzukun 34.36
−−−−−−−−−−−−−Pinch roller 35−−−−
−−−−−−−・−−−1−− Cabzukun 37−−−
−−−−−−−−−−−−−−−−−0 ring 39−−
−−−−−−−−−−−−1 Workpiece Patent Applicant Inoue Japax Co., Ltd. Agent (7524) Mogami Seita Section Diagram 4 Procedure Neichi Seiji: (Method) % Formula % 1 , Incident Display 1982 Patent Application No. 239822 2
, Title of Invention Wire Cut] - Electrical Discharge Machining Method and Apparatus 3, Relationship with the Amendment Case Patent Applicant Address 5289 Michisho, Nagatsuta-cho, Midori-ku, Yokohama, Kanagawa Prefecture Name (048) Benjoja Co., Ltd. Kiyoshi Inoue, Representative of PAX Institute

Claims (1)

[Claims] ■) In wire-cut electrical discharge machining, a thin tube-shaped electrode rotated around a central axis is used to form a hole for electrode insertion in a workpiece, and the fine hole for electrode insertion is A wire cut electrical discharge machining method, which is a method for automatically inserting a wire electrode to start electrical discharge machining, and comprising the steps described in the following items a) to h). a) A step of attaching a thin tubular electrode to a chuck that is rotatable and movable up and down. b) Step of inserting the wire electrode into the capillary electrode. C) A step of gripping the wire electrode so that it is moved in the axial direction together with the capillary electrode by a clamp provided on the member supporting the chuck. d) A step of aligning or cutting the tip of the wire electrode so that it is substantially flush with the tip of the capillary electrode. e) Supplying machining fluid to the center hole of the capillary electrode, applying a voltage pulse with the tips of the capillary electrode and wire electrode facing the workpiece, and applying machining feed to the capillary electrode while rotating it. The process of machining the pores for electrode insertion while feeding. f) A step of stopping the rotation and power supply of the capillary electrode after completing the processing of the electrode insertion hole. g) A step of releasing the grip on the wire electrode and feeding the wire electrode to a wire electrode take-up device. h) A step of pulling out the tubular electrode from the electrode insertion hole. 2) A wire-cut electrical discharge machining device comprising the components described in items i) to r) below. i) A thin tubular electrode having a wire electrode and a central hole for passing the machining fluid therein. j) A chuck that removably supports the capillary electrode. k) A holder that supports the chuck in a rotatable and movable manner. (2) A wire electrode supply device for inserting a wire electrode into the center hole of the capillary electrode. m) A chuck rotation device that is attached to the holder and provides rotational motion to the chuck. n) An elevating device that is coupled to the holder and supports the holder so that it can move up and down. 0) A clamp that is provided on the holder and grips the wire electrode so that the wire electrode is processed and fed in the axial direction together with the tubular electrode only when processing the electrode insertion hole. p) A cutter for cutting the wire electrode protruding from the tip of the capillary electrode in substantially the same plane as the tip of the capillary electrode. q) A power supply circuit that supplies electrical discharge machining voltage pulses to the thin tubular electrode during machining of a small hole for electrode insertion, and supplies electrical discharge machining voltage pulses to the wire electrode during wide cassette electrical discharge machining. r) A wire electrode take-up device that is provided at a position facing the capillary electrode via the workpiece, and takes out the wire electrode sent out from the tip of the capillary electrode to the processing part along a desired path.