JPH02279230A - Small hole electric discharge machining method - Google Patents

Abstract

PURPOSE:To improve the efficiency of removing machining chips existing in an electric discharge machining portion, which are generated by electric discharge machining by oscillating and moving an X-Y table to which a workpiece is fitted during machining or after the completion of small hole electric discharge machining to oscillate the workpiece and cause the relative motion of an electrode and the workpiece. CONSTITUTION:A small hole such as a start hole or the like is bored in a workpiece by electric discharge machining, and after the completion of electric discharge machining the small hole, an X-Y table 21 to which the workpiece 8 is fitted is oscillated. By this operation, the relative motion of a wire electrode 1 and the workpiece 8 is caused to remove machining chips existing in an electric discharge machining portion, which are produced by small hole machining.

Description

[Detailed Description of the Invention] [Field of Industrial Application] This invention is applicable to start hole machining for wire electrical discharge machining of workpieces such as cemented carbide and hardened steel, difficult-to-process materials such as copper and stainless steel, and curved surfaces. , relates to a small hole electric discharge machining method that can perform small hole machining on a workpiece having a tapered surface.

[Conventional technology]

Conventionally, for example, wire electrical discharge machines machine workpieces made of cemented carbide, hardened steel, etc. using the part where the wire electrode runs, but For this purpose, a start hole is required, and a small hole electric discharge machine or a wire electric discharge machine with a start hole machining device is provided as a device for machining a small hole such as the start hole machining. In addition, the small hole electric discharge machine also has
It is used to drill small holes in difficult-to-process materials such as copper and stainless steel, and in workpieces with curved and tapered surfaces. In such a small hole electric discharge machine or a start hole machining device, a pipe electrode holding device is attached to the tip of the rotating main shaft, and the pipe electrode holding device is usually attached with a diameter of φ0.
High-pressure water (usually 30 kg/- to 100 kg/
cd) is ejected from the tip of the pipe through the pipe of the pipe electrode, and is discharged between the pipe electrode and the workpiece to open small holes in the workpiece.

[Problem to be solved by the invention]

By the way, as mentioned above, when performing electric discharge machining of a small hole such as a start hole on a workpiece, a wire electric discharge machine with a start hole machining device or a dedicated small hole electric discharge machine is required. Installation requires removal, and the device itself has a complex structure. Therefore, the present applicant previously filed an application in Japanese Patent Application No. 63-259326 for a system for electrical discharge machining a small hole such as a start hole in a workpiece using a wire electrode using a wire electrical discharge machine itself.

However, when electrical discharge machining a small hole such as a start hole on a workpiece, a wire electrical discharge machine with a start hole machining device, a dedicated small hole electrical discharge machine, or a wire electrical discharge machine itself is used. Even if you do,
Machining waste is generated when drilling small holes. During rough machining, the discharge gap is large and the discharge energy is large, so the machining debris is removed with explosive force, but when drilling a deep hole in a workpiece or finishing machining, the discharge gap is small. (Since the discharge energy is also small, a phenomenon occurs in which machining debris is not removed efficiently. Therefore, conventionally, for removing machining debris generated in electrical discharge machining, for example, a sensor that detects the removal state of machining debris is used. When machining debris begins to accumulate between the electrode and the workpiece, the sensor detects this condition, and in response to the detection signal, the electrode is moved up and down by the servo control, and the pumping action of the electrode removes the machining debris. In some cases, machining fluid is jetted from the side of the electrode or a hole in the electrode to remove machining debris, or machining debris is removed by suction from the side of the electrode or through a hole in the electrode. Or, the electrode is rotated to increase the effect of removing machining waste, but if the electrode cannot be rotated, there is no effect at all, and in any case, a sufficient effect of removing machining waste cannot be obtained. The problem is that I can't.

The purpose of this invention is to solve the above problems,
Machining small holes such as start holes on workpieces using a wire electrical discharge machine with a start hole processing device, a dedicated small hole electrical discharge machine, or the wire electrical discharge machine itself, especially deep small hole processing on workpieces. In order to efficiently remove machining debris generated during finishing machining where the discharge gap is small and the discharge energy is low, in addition to conventional methods of eliminating machining debris such as vertical movement and rotational movement of the electrode, By making a relative rocking motion between the machine and the workpiece, the effect of removing machining debris is achieved smoothly, and as a result,
A small hole that can stabilize the machining condition, increase machining speed and improve machining efficiency, prevent the occurrence of arc discharge, etc., improve machining accuracy on the workpiece, and prevent horizontal scratches on the electrode. An object of the present invention is to provide an electric discharge machining method.

CyA! ! I! Means for Solving the Problem] In order to achieve the above object, the present invention is configured as follows.

That is, in this invention, a holder to which a supply pipe is fixed is lowered along a guide loft fixed to a head, and the lower end surface of the supply vibrator is opposed to a workpiece attached to an XY child table at a predetermined distance, A wire electrode sent out from a source bobbin is passed through the supply pipe, and the wire electrode is supplied so as to protrude from the lower end surface of the supply pipe, and then a wire electrode is provided between the wire 1 hole at the protruding part and the workpiece. A voltage is applied to discharge the workpiece, and the discharge energy is used to discharge a small hole in the workpiece, and as the small hole machining progresses, the wire electrode is sent in to discharge the small hole in the workpiece. At the same time, the remaining amount of machining debris existing between the wire electrode and the workpiece is detected, and in response to a detection signal in which the detected amount of machining debris is equal to or greater than a predetermined value, the XY child table The present invention relates to a small hole electric discharge machining method characterized in that relative movement is performed between the workpiece and the wire electrode by swinging the workpiece.

In addition, the present invention lowers a holder to which a pipe electrode is fixed along a guide rod fixed to a head, and causes the lower end surface of the pipe electrode to face a workpiece to which an XY child table is attached at a predetermined distance, Next, an inter-electrode voltage is applied between the pipe electrode and the workpiece to cause a discharge, and the discharge energy is used to perform electrical discharge machining of a small hole such as a start hole in the workpiece. Detecting the remaining amount of machining waste existing between the poles between the
The present invention relates to a small hole electric discharge machining method characterized in that a Y child table is oscillated to cause relative movement between the workpiece and the wire electrode.

[Effect]

The small hole electrical discharge machining method according to the present invention is configured as described above and operates as follows. That is, this invention:
A small hole such as a start hole is electrically discharged into the workpiece, and after the electrical discharge machining of the small hole is completed, relative movement is created between the wire electrode and the workpiece by swinging the XY child table to which the workpiece is attached. This makes it possible to improve the removal efficiency of machining debris present in the electrical discharge machining area generated by small hole machining.

In addition, when electrical discharge machining a small hole such as a start hole using the wire electrode itself for wire electrical discharge machining, after machining the start hole, the workpiece cannot be reinstalled and the workpiece can be installed as it is without wire discharge machining. Machining can be carried out without causing poor positioning of the start hole, and the efficiency of removing machining debris can be greatly improved.

〔Example〕

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a wire electrical discharge machine that achieves a small hole electrical discharge machining method according to the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic front view showing a state in which start hole machining is performed with a wire electric discharge machine that can achieve the small hole electric discharge machining method according to the present invention.

This wire electrical discharge machine is capable of, for example, performing wire electrical discharge machining on a workpiece 8 into a predetermined machining shape using the wire electrode 1, and electrical discharge machining of a small starting hole or the like through which the wire, which is the wire electrode 1, penetrates. The head 10 constituting the wire electrical discharge machine is equipped with an automatic wire feeding device. The workpiece 8 is also fixed by a clamp 22 on a cross slide or XY child table or a work table or XY table 21 mounted on the cross slide which is operated in a servo function by a servo motor. This XY child table 1 normally moves in the X direction and the Y direction according to the machining status of the workpiece 8 by commands from an NC device when wire electric discharge machining is performed. Wire h! The supporting body 9 constituting an automatic wire feeding device is attached to the upper part of the blade 10 of the Lt processing machine, and the supporting body 23 to which the upper wire head 6 is attached is attached to the lower part of the head 10, as well as the A support body 24 to which rollers 18 and the like for guiding the supply pipe 5 and the wire to the pole 1 are attached is fixed.

A pair of guide rods 3 are arranged between the support body 9 and the support body 24. These guide rods 3 include
A holding body 20 is attached so as to be slidable in the vertical direction.

A supply pipe 5 for guiding the wire electrode 1 is fixed to the holder 20 with a set screw 25, etc., and a thread guide 12, a pair of annealing rollers 4 having the function of power supply pins, and a pipe holder 13 are also attached to the holder 20. ing. The pair of annealing rollers 4 have the function of pinching the wire electrode l fed through the thread guide 12 attached to the holder 20 and feeding it into the supply pipe 5. A direction changing roller luff and a felt brake roller 11 are attached to the support body 9, and the wire electrode 1 is configured to be fed into the supply pipe 5 with a predetermined tension applied thereto.

Furthermore, a slide rail 14 is fixed to the support body 24 attached to the head 10 in order to make the sliding movement of the supply pipe 5 smooth. In the support body 24, a cutter 16 is installed below and adjacent to the slide rail 14. This cutter 16 is provided to cut the wire electrode 1 in order to prepare a good wire electrode end. In the support body 24 fixed to the head IO, below the cutter 16, a power supply bin 17 and a wire electrode 1 are provided.
A pair of common rollers 15, rollers 18, etc. are provided to guide the rollers. Further, a wire electrode 1 is provided on the support 23 which is close to the lower surface of the support 24 and is fixed to the head 10.
A roller 18 for guiding the supply pipe 5, a pipe stopper 19 for preventing the supply pipe 5 from further descending and protruding when the tip of the supply pipe 5 comes into contact with it, and an upper wire head 6 are attached. There is.

In order to achieve the small-hole electrical discharge machining method according to the present invention, this wire electrical discharge machine is designed to particularly reduce the extent to which machining debris generated by electrical discharge machining remains between the wire electrode l and the workpiece 8. A processing waste detection sensor is provided to detect the removal state of waste. This processing waste detection sensor is
For example, the ion state present in the machining fluid at the electrical discharge machining site between the wire electrode l and the workpiece 8 may be electrically detected, and the remaining amount of machining debris present at the electrical discharge machining site may be detected based on the electrical signal. It is something that can be done. This processing waste detection sensor detects the remaining amount of processing waste existing between the wire electrode 1 and the workpiece 8, and the detection signal is sent to the NC
input to the device or controller. If the amount of machining debris detected by the machining debris detection sensor is greater than or equal to a predetermined value, the controller responds to the detection signal and issues a command to perform an oscillating operation to oscillate the XY child table 1 of the wire electric discharge machine. emanate. Due to the rocking of the XY child table 1, relative interlocking is performed between the workpiece 8 and the wire electrode 1, and the wire electrode 1
The machining debris present in the space between the poles 1 and 8 is removed from the space by the jet action of machining fluid or the pump action caused by the vertical movement of the pole 1 of the wire 11. Here, for the oscillating operation of the XY child table 1, for example, the oscillating machining method used in conventional die-sinking electrical discharge machines can be applied. As an example of the swinging operation, circular movement of the XY child table, radial swinging at an arbitrary angle, etc. can be used. For the XY child table circular motion or radial swing, the swing width, swing speed, approach speed, return to swing starting point, swing depth, swing mode, etc. are set in advance.

The wire electrode 1 is wound up on a source bobbin, and the acid source bobbin is loaded into a wire electrical discharge machine, and the wire electrode 1 is unwound from the source bobbin by an automatic wire feeding device. For example, the wire running system includes a direction changing roller, a tension roller, a brake roller, a wire electrode disconnection sensor, etc., and the wire electrode I is connected to the workpiece 8 through the wire running system. It is sent to the processing area. In FIG. 1, a direction changing roller 2 located downstream of the tension roller of the wire running system is shown, and the wire electrode 1 is connected to the direction changing roller 2, the felt brake roller 11, the thread guide 12, the direction changing roller 1, the felt brake roller 11, the thread guide 12,
The wire passes through the annealing roller 4, the supply vibrator 5, the common roller 15, and the guide roller 18 in order, is fed to the upper wire to the rad 6, and is finally fed to the electrical discharge machining area with the workpiece 8. As shown in the figure, the holder 20 is moved downward along the guide rod 3, and the lower end of the supply vibrator 5 is attached to the support 24.
When placed on the top surface of the pipe stopper 19 attached to the pipe stopper 19, when machining a small hole such as a start hole on the workpiece 8, or when performing wire electric discharge machining on a predetermined machining shape on the workpiece. 2 shows the case where the wire electrode 1 is set by passing the wire electrode 1 through the start hole of the workpiece 8. Although not shown, when the holder 20 is moved upward along the guide loft 3 and the lower end of the supply pipe 5 is positioned above the cutter 16 attached to the support 24, the work The process of wire electrical discharge machining a predetermined machined shape on an object, the process of cutting the wire electrode after wire electrical discharge machining of the machined shape, and the process of cutting and removing the tip of the wire electrode l when performing small hole electrical discharge machining. be.

Next, an example of the small hole electric discharge machining method according to the present invention will be described with reference to FIGS.
This will be explained with reference to the operation flowcharts shown in FIG. 3B) and FIG. 3C.

First, in order to machine a start hole in the workpiece 8 using a wire electrical discharge machine, the workpiece 8 is set on the XY child table 1, the main switch, motor, servo motor, etc. of the wire electrical discharge machine are turned on, and the automatic wire Activate the supply device (step 30).

By the operation of the automatic wire feeding device, the wire electrode 1 is passed from the source bobbin through various rollers such as a tension run roller, a direction change roller, etc., to a direction change roller 27, a felt brake roller 11, and so on. Thread guide 12, annealing roller 4
into the supply vibrator 5 through the wire electrode l.
is set so that the tip thereof is exposed and protrudes from the lower end of the supply pipe 5 (steps 31 and 32).

At the same time as the wire IT pole 1 is supplied to the supply pipe 5, the holder 20 is lowered along the guide iron 3, and the holder 2
The lower end of the supply pipe 5 fixed at
Continue the lowering operation until contact with point 9 (step 33).
.

According to the above process, the position of the work table 21 on the cross slide is adjusted by operating the servo motor feed mechanism, and electrical discharge machining of a small hole such as a start hole is performed on the workpiece 8 fixed to the work table 21. The wire electrode 1 is sent out so that it is positioned above and facing the area to be treated (step 34).

Scrape the wire and the lowering position and work! A position sensor detects and determines whether or not the position setting of 1ff8 is completed, and when the position setting is completed, a machining fluid supply device is used to perform electric discharge machining of a small hole such as a start hole in the workpiece 8. is activated to eject machining fluid from the jet nozzle, and if the position setting has not been completed, the positioning of the wire electrode 1 and workpiece 8 is continued (step 35). At this time, the machining waste detection sensor is activated. , the state is set to electronically detect the state in which machining debris has accumulated between the seeds.

A voltage between the electrodes is applied between the workpiece 8 and the wire electrode 1, a discharge is caused between the workpiece 8 and the wire electrode 1, and the discharge energy is used to perform electrical discharge machining of a small hole such as a start hole in the workpiece 8. . In this case, the wire feeding device is operated to control the feeding of the wire electrode 1 in accordance with the progress of drilling a small hole in the workpiece 8 (step 36).

■ Wire electrode 1 and workpiece 8 are detected by the workpiece detection sensor.
In step 37), it is determined whether or not more than a predetermined amount of machining debris remains between the poles of the C! The XY child table 1 to which the workpiece 8 is attached is oscillated by a command from the machine (step 38).

The swing motion of the XY child table 1 causes the workpiece 8 and the wire electrode 1 to move relative to each other, promoting the removal of machining debris, and the detection signal of the machining debris detection sensor is detected by the chip 40).

When the XY child table 1 is to be oscillated, the time T of the oscillation movement of the XY child table 1 should be measured using a timer.Step 4
1) Determine whether the cough 1g movement time T is less than the predetermined time T0.Step 42) Even if the predetermined time T0 or more elapses, there is no discharge between the wire electrode 1 and the workpiece 8. If more than a predetermined amount of machining debris remains in the machining area, it is assumed that an abnormal condition has occurred such as a small hole such as a start hole being clogged with foreign matter other than machining debris, or a state in which machining debris has solidified. Issue an alarm of abnormal signal Step 7 43
), the operation of the wire electric discharge machine is stopped (step 44
).

In addition, if the remaining amount of machining debris detected by the machining debris detection sensor is below a predetermined value, there will be no problem in machining a small hole, so that a voltage will be generated between the workpiece 8 and the wire electrode 1 depending on the inter-electrode voltage. The voltage value (■) of the machining voltage is appropriately detected, and it is determined whether or not the voltage value (V) is greater than or equal to a predetermined voltage value (Step 4).
5).

If the machining voltage value ■ is equal to or higher than the predetermined voltage value 70, the wire electrode 1 is not worn out and is in a normal state, and the fine hole electric discharge machining can be continued. Hole electrical discharge machining is continued (step 46), and if the machining voltage value ■ is less than the predetermined voltage value V, it is determined that the wire electrode 1 is in an abnormal state and has been consumed, and the wire electrode 1 is The tip part is cut and removed, and the normal tip part of the wire electrode 1 is exposed from the supply vibrator 5 (proceeding to step 55). Of course, it may be configured to detect current.

If the wire electrode 1 is in a normal state and has not yet been consumed, in order to continue small hole electrical discharge machining, a voltage between the electrodes is continuously applied between the workpiece 8 and the wire electrode 1, and the electrical discharge is repeated. Continue machining the start hole on the workpiece 8 (Step: Detect and judge whether or not the predetermined small hole machining on the workpiece 8 has been completed using a sensor, etc. (Step 47), the machining of the small hole is completed. If not, the small hole machining continues (step 46).

When the small hole machining is completed, the small hole electric discharge machining by the wire electric discharge machine ends. The application of the voltage between the electrodes 1 and the workpiece 8 is stopped, and the discharge is interrupted (step 48).

Next, the automatic wire feeding device is activated to run and feed the wire electrode 1, to pass the wire electrode 1 into the starting hole of the workpiece 8 which has been subjected to small hole electrical discharge machining, and to insert the wire electrode 1 into the wire drawer provided downstream. The wire electrode 1 is set by being clamped by the device and brought into a running state (step 49.50).

Move the holding body 20 upward along the guide rod 3,
It is raised to the position shown in FIG. 1 (step 51).

By raising the holder 20, the wire electric discharge machine is set to a state in which wire electric discharge machining can be performed on the workpiece 8.

Therefore, as in normal electric discharge machining, a voltage is applied between the wire electrode I and the workpiece 8 to cause an electric discharge, and the electric discharge energy generated by the electric discharge is used to perform electric discharge machining to form a predetermined machined shape on the workpiece 8. (step 52).

It is determined by detecting whether electrical discharge machining of a predetermined machining shape has been completed on the workpiece 8 (step 53), and if the predetermined machining shape has not been electrically machined on the workpiece 8, normal wire discharge machining is performed. Electric discharge machining is continued according to the machining method (step 52).

When the electric discharge machining of the predetermined machining shape is completed on the workpiece 8, the operation of the wire electric discharge machine is stopped and the workpiece 8 is
The above-mentioned steps are repeated in order to perform electrical discharge machining of the next start hole.

If there is no need to perform electrical discharge machining on the workpiece 8 attached to the work table 21, replace it with another workpiece 8 and process it according to each step in the same manner as above (step 54).

By the way, in step 45, the machining voltage value ■ is a predetermined voltage value ■. If it is below, it is determined that the wire electrode I is in an abnormal state and the tip of the wire electrode I is worn out,
Since the small-hole electrical discharge machining of the start hole on the workpiece 8 cannot be continued, the application of the inter-electrode voltage between the wire electrode l and the workpiece 8 is stopped, and the electrical discharge machining is interrupted (step 55
).

The holder 20 fixing the supply vibrator 5 is raised along the guide rod 3, and the lower end of the supply vibrator 5 is positioned above the cutter 16 attached to the support 24 fixed to the head IO (step 56).

The lower end of the supply vibrator 5 is located above the cutter 16,
A sensor such as a limit switch detects and determines whether or not it is set at a predetermined position.

When the lower end of the supply vibrator 5 is set above the cutter 16, the upward movement of the holder 20 is stopped and the process proceeds to the next step 50, and when it is not set at the predetermined position, Subsequently, the lifting operation of the holding body 20 is continued (step 57).

The lower end of the supply vibrator 5 is cut off! When positioned above 1f16, actuate the cutter 16 to cut off the worn out portion of the wire 1i pole 1, that is, the tip of the wire electrode 1, and remove the cut wire electrode 1 by appropriate means. .

By eliminating the consumable part of the wire electrode 1, the tip of the wire electrode 1 becomes a good wire electrode part again.Next, in order to expose the tip of the normal wire 1fil from the supply vibe 5, the processing is performed in step Proceed to 31,
Subsequently, according to each of the steps described above, processing for small hole electrical discharge machining of a small hole such as a start hole in the workpiece 8 using the wire electrode 1 is performed (step 5859).

It goes without saying that the above-mentioned removal of machining waste can also be applied to the general small-hole electric discharge machine shown in FIG. 1 or the wire electric discharge machine with a start hole machining device.

FIG. 2 shows an example of a small-hole electrical discharge machine for achieving the small-hole electrical discharge machining method according to the present invention. In this small-hole electrical discharge machine, the head 60 to which the vibrator electrode is attached is configured as follows. That is,
The cough head 60 is attached to a Z-axis slide 61 of a small-hole electric discharge machine or a wire electric discharge machine with a start hole machining device so as to be movable in the vertical direction. head 60
A rotating shaft 62 is attached to the rotating shaft 62, and an electrode coverr 63 is detachably attached to the rotating shaft 62.

This electrode coverr 63 is equipped with a vibrator electrode in order to perform small hole electrical discharge machining on a workpiece fixed to a work table 64. The work table 64 is attached to a cross slide 65 placed on a bed base 66. Z
An electrode guide 67 is attached to the shaft slide 61 for guiding a vibrator of a vibrator electrode attached to the electrode coverr 63.

When electrical discharge machining a small hole or hole in a workpiece using a small hole electrical discharge machine, or a small hole using a start hole machining device, the workpiece is fixed on the work table 64 with a clamp, and the electrode cover of the rotating shaft 62 is Vibrator tw for 63
Attach the iA, lower the hendro 0, and set the lower end of the pipe electrode close to the workpiece. In addition, in the figure, 68
69 is an operation panel, 69 is a digital counter, 70 is a Z-axis lamp, 71 is a hydraulic bar, and 72 is a water tank.

When electrical discharge machining a small hole or pores in a workpiece using a small hole electrical discharge machine or a start hole processing device as shown in Fig. 2, it can be achieved by the same machining process as in the past. A small hole electrical discharge machining method incorporating a process for removing machining debris similar to that described above can be applied to such a small hole electrical discharge machine or a start hole machining device. The process of removing machining debris in the small hole electrical discharge machining method can be carried out in exactly the same manner as the process described in steps 37 to 44 described above, so the description of these processes will be omitted here. , will be omitted as it is redundant.

C. Effects of the invention] The small hole electric discharge machining method according to the invention is configured as described above, and has the following effects.

That is, the present invention provides a method for cutting the workpiece during the machining process of electrical discharge machining a small hole such as a start hole in the workpiece using electrical discharge energy generated between an electrode and the workpiece, or after completing electrical discharge machining of the small hole. The workpiece can be moved by swinging the XY child table attached to it! Since the electrode and the workpiece are caused to move relative to each other by the f-motion, the removal efficiency of machining debris present in the electrical discharge machining area generated by electrical discharge machining can be improved. In other words, the effect of removing machining debris existing between the machining holes is achieved smoothly, and as a result, the machining condition is stabilized, machining speed is increased, machining efficiency is increased, and arc discharge etc. caused by the presence of machining debris is eliminated. to prevent the occurrence of and improve the machining accuracy of the workpiece,
It is also possible to prevent the electrode from being damaged.

In addition, when electrical discharge machining a small hole such as a start hole using the wire electrode itself for wire electrical discharge machining, after machining the start hole, the workpiece can be installed as is without resetting the workpiece. It is possible to move on to the machining process, and there is no positioning error that occurs when positioning the start hole by setting the workpiece against the electrode, reducing the machining accuracy for the workpiece. Moreover, the removal efficiency of processing waste can be greatly improved.

[Brief explanation of drawings]

FIG. 1 is a schematic front view showing an example of a wire electrical discharge machine that achieves the small hole electrical discharge machining method according to the present invention, and FIG. 2 shows an example of a small hole electrical discharge machine that achieves the small hole electrical discharge machining method according to the present invention. Schematic front view shown in Fig. 3 (A) and Fig. 3 (B)
and FIG. 3(C) is an operation flow diagram showing an example of the operation for achieving the small hole electric discharge machining method according to the present invention. 1------Wire electrode, 3---Guide rod, 5 Supply pipe, 6---Upper wire head, 8-
...workpiece, 10.60--head, 16--
-Cutter, 20...-Holder, 21--X
Y table, 65--cross slide (XY child table.

Claims (2)

[Claims] (1) Lower the holder to which the supply pipe is fixed along the guide rod fixed to the head, place the lower end of the supply pipe to face the workpiece attached to the XY table at a predetermined distance, and move it away from the source bobbin. A wire electrode to be sent out passes through the supply pipe and is supplied in a state where it protrudes from the lower end surface of the supply pipe, and then a voltage between the electrodes is applied between the wire electrode at the protruding portion and the workpiece. The electric discharge energy is used to discharge a small hole in the workpiece, and as the small hole machining progresses, the wire electrode is sent in to perform the small hole electric discharge machining on the workpiece, and the wire electrode and the workpiece, and in response to a detection signal in which the detected amount of machining scraps is equal to or higher than a predetermined value, the XY table is oscillated to remove the workpiece. A small hole electrical discharge machining method characterized by causing relative movement between an object and the wire electrode. (2) The holder to which the pipe electrode is fixed is lowered along the guide rod fixed to the head, the lower end surface of the pipe electrode is opposed to the workpiece attached to the XY table at a predetermined distance, and then the pipe A gap voltage is applied between the electrode and the workpiece to cause a discharge, and the discharge energy is used to discharge a small hole in the workpiece, and also to create a gap between the wire electrode and the workpiece. The remaining amount of machining debris present is detected, and in response to a detection signal in which the detected amount of machining debris is greater than or equal to a predetermined value, the XY table is oscillated to provide relative interlocking between the workpiece and the wire electrode. A small hole electrical discharge machining method characterized by performing the following steps.