JP2002301623A - Fine hole electric discharge machine and fine hole electric discharge machining method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fine hole electric discharge machine to properly select an electrode change form where electrode is changed by a single fine hole electric discharge and an electrode change form where an electrode with a given diameter grasped by an electrode hole is replaced with an electrode with the same diameter according to consumption and a given electrode is changed together with an electrode holder as occasion demand and machining is effected, and an availability factor and flexibility are improved. SOLUTION: The fine hole electric discharge machine comprises an automatic electrode feeding device 14 to feed a number of electrodes with a given diameter one by one to the tip charge of a machining main spindle 10; a first electrode to removably rasp the feed electrode with the feed electrode mounted on the machining main spindle; a number of second electrode holders 122 to grasp an electrode with a diameter different from that of an electrode with a given diameter; an ATC device 19 to change an electrode holder mounted on a machining main spindle with the proper electrode holder of first and second electrode holders; an automatic electrode grasping release mechanism capable of automatically grasping and releasing the feed electrode the first electrode holder in a state to be mounted on a machining spindle; and an electrode recovering device 20 to recover and transfer a consumed electrode from the first electrode holder and contain it in a recovery container.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention uses a thin wire or a thin rod-shaped tool electrode as a fine hole machining electrode, and covers the fine hole machining electrode (hereinafter abbreviated as an electrode) through a discharge gap. While facing the workpiece and interposing a machining fluid in the discharge gap, an intermittent voltage pulse is applied between the electrode and the workpiece to repeatedly generate a discharge pulse, and a discharge pulse is generated between the electrodes in the facing direction. The present invention relates to a small-hole electric discharge machine and a small-hole electric discharge machining method for forming a small hole in a workpiece by giving a relative machining feed.

[0002]

2. Description of the Related Art Generally, a small hole electric discharge machine is used as an electrode to have an outer diameter of about 0.1 mm to about 3 mm and a length of 200 mm.
Using a hollow cylindrical pipe electrode of about mm, an aqueous or oil-based working fluid is supplied through a hollow portion of the pipe electrode at a high pressure of 20 kg / cm2 or more to a discharge gap at an opening at the tip end to perform processing. . As described above, the electrode used for the small hole electric discharge machining has a small diameter and is machined under high wear conditions, so that the electrode is used up in a large amount at the time of machining.

For this reason, when a large number of small holes having a single hole diameter are to be machined, an automatic electrode supply device that supplies a new electrode to an electrode holder attached to the tip of the machining spindle and holds the electrode is used. A small-hole electric discharge machine equipped with an electrode collecting device for collecting and transferring electrodes from the electrode holder and automatically storing the collected electrodes in a collecting container is often used.

This automatic electrode supply device supplies an electrode cartridge containing a large number of electrodes having a single outer diameter, and supplies the electrodes one by one from the electrode cartridge to an electrode holder at a tip portion through a hollow portion of a machining spindle. And an electrode feeder device, and is mounted above the machining spindle. And the electrode collection device, an electrode transfer device that grips the electrode released from the electrode holder and transfers it to the collection position,
And an electrode collection container that receives the electrode by moving from the retreat position to the collection position, and is usually provided near the lower part of the processing spindle. In a small hole electric discharge machine equipped with this type of automatic electrode supply device, the outer diameter of the electrode is φ0.
In general, a pipe electrode of about 5 mm or more is used.

In this kind of small-hole electric discharge machine, after the consumable electrode is removed by an electrode collecting device, the electrode supplied from the automatic electrode supply device is protruded from the tip of the electrode holder by a predetermined length. An automatic electrode gripping release mechanism that enables automatic gripping of the electrode by the electrode holder and release from the gripping state so that the electrode holder adjusts the state and causes the electrode holder to grip the electrode, and temporarily holds the tip of the supplied electrode. And a clamp mechanism for temporarily fixing.

The automatic electrode supply device includes a plurality of electrode cartridges each accommodating an electrode having a different diameter, and a plurality of electrode feeders corresponding to the plurality of electrode cartridges. Each set of the electrode feeder device and the electrode feeder device is placed on an indexing table positioned by an indexing device, and a desired set of the electrode cartridges and the electrode feeder device in each of the sets is set to an electrode above the processing spindle. By providing a multi-head type automatic electrode supply device that can be positioned at the supply position, several types of small holes having different hole diameters can be efficiently machined even by this kind of small hole electric discharge machine.

On the other hand, when machining of various different hole diameters is required, an automatic tool electrode exchange device (ATC device) for exchanging an electrode holder attached to an electrode holder chuck at the tip of a machining spindle with another electrode holder. Are used. This ATC apparatus has an electrode holder magazine for individually and detachably accommodating a large number of electrode holders each holding a different outer diameter or a different type of electrode, and an electrode holder between the electrode holder magazine and the electrode holder chuck. After the electrode holder mounted on the electrode holder chuck is transferred to the electrode holder magazine by the transfer device, an electrode having an outer diameter corresponding to the hole diameter to be processed is provided. The electrode holder to be gripped is selected from the electrode holder magazine, and the electrode holder is replaced by transferring the electrode holder to the electrode holder chuck by the transfer device. Further, the electrodes consumed by the processing are removed from the electrode holder chuck together with the electrode holder by the ATC device, and are housed in the electrode holder magazine. In a thin hole electric discharge machine equipped with this ATC device, a pipe electrode having an outer diameter of about 0.1 mm to about 3 mm is generally used as an electrode.

[0008] The small hole electric discharge machine provided with the above-mentioned automatic electrode supply device and the electrode collection device is characterized in that the electrode holder is not detachable but fixed to and integrated with the machining spindle.
It is equipped with an automatic electrode gripping release mechanism and an electrode recovery device that automatically grips and releases the supplied electrode from the gripping state. The configuration is different. The conventional electric discharge machine is a dedicated machine, and it is equipped with the above-mentioned automatic electrode supply device suitable for machining many small holes of a single diameter or a small variety of different diameters. And the latter AT suitable for machining a large number of small holes with a single diameter and various kinds of small holes with different diameters
A small-hole electric discharge machine equipped with a C device has been put to practical use as a different electric discharge machine.

[0009]

However, recently,
Under the situation where the necessity of small hole machining is increasing remarkably, the efficiency of the machining form in which the two small hole electric discharge machines are selectively used is inefficient, so that one small hole electric discharge machine has a single diameter. It is a highly versatile and highly efficient machine that can cope with all of the processing of a large number of small holes, the processing of various kinds of small holes with different diameters, and the continuous processing by combining these. There is a demand for the provision of a hole electric discharge machine. In view of such a problem, the present invention uses a single small-diameter electric discharge machine to replace electrodes of a predetermined diameter held by an electrode holder with electrodes of the same diameter one after another in accordance with wear and tear. The electrode exchange mode for gripping and the electrode exchange mode for selecting a predetermined electrode holder from a large number of electrode holder groups each holding various types of electrodes having different diameters and exchanging the electrode together with the electrode holder are appropriately selected as necessary. It is an object of the present invention to provide a small-hole electric discharge machine and a small-hole electric discharge machining method capable of performing machining by using the method.

[0010]

To achieve this object, a thin hole electric discharge machine according to the first aspect of the present invention is provided at a tip end of a rotation-controlled machining spindle and automatically attaches and detaches an electrode holder. An electrode holder chuck for accommodating a large number of fine hole processing electrodes having a predetermined diameter; and an electrode for supplying the fine hole processing electrodes one by one from the electrode cartridge to the distal end side through the hollow portion of the processing spindle. An automatic electrode supply device, which is provided above the processing spindle; and a first electrode which is formed so as to be automatically detachable by the electrode holder chuck and is capable of gripping the fine hole processing electrode.
Automatic gripping and gripping of the fine hole drilling electrode supplied to the tip side of the processing spindle by the automatic electrode supply device by the first electrode holder mounted on the electrode holder chuck. An automatic electrode gripping and releasing mechanism which enables release from the state; a second electrode which is formed so as to be automatically attached and detached by the electrode holder chuck and grips a fine hole processing electrode different from the fine hole processing electrode. An electrode holder magazine capable of individually and removably accommodating the first and second electrode holders respectively, and the first or second electrode holder being disposed between the electrode holder magazine and the electrode holder chuck. And an electrode holder transfer device that transfers the first and second electrodes.
An automatic tool electrode changing device for replacing a second electrode holder with a predetermined first or second electrode holder in the electrode holder magazine; and An electrode transfer device that has an electrode transfer device that collects and transfers a predetermined-diameter fine-hole processing electrode, and an electrode collection container that stores the predetermined-diameter fine-hole processing electrode transferred by the electrode transfer device; It is characterized by comprising.

According to a second aspect of the present invention, the first electrode holder has a spring collet capable of gripping a fine hole machining electrode having a predetermined diameter and a tightening nut for tightening the spring collet. A key formed on the first electrode holder, and a key formed on the tip end of the machining spindle so as to be fitted with the key in a state where the first electrode holder is mounted on the electrode holder chuck. Grooves and
It consists of a nut gripper that grips the tightening nut, and automatically rotates the processing spindle while holding and fixing the tightening nut by the nut gripper to automatically grip and release the narrow hole processing electrode with a predetermined diameter from the gripping state. It is characterized by being performed.

According to a third aspect of the present invention, the electrode holder transferring device of the automatic tool electrode changing device and the electrode transferring device of the electrode collecting device are driven by the same driving means. It is characterized by.

According to a fourth aspect of the present invention, there is provided a small-hole electric discharge machine, wherein the automatic electrode supply device comprises a plurality of electrode cartridges each accommodating a small-diameter machining electrode having a predetermined diameter different from each other. An electrode cartridge containing a plurality of electrode feeders corresponding to each electrode cartridge mounted on an indexing table positioned by an indexing device and accommodating an electrode for processing a fine hole having a desired diameter, and the electrode cartridge. And a multi-head type automatic electrode supply device capable of aligning an electrode feeder device corresponding to the above with an electrode supply position above the processing spindle.

According to a fifth aspect of the present invention, there is provided the small hole electric discharge machine, wherein the electrode holder magazine of the automatic tool electrode changing device is capable of individually and detachably accommodating the first and second electrode holders. Are provided at predetermined intervals on the endless rotating member,
An electrode holder transfer device for holding the first or second electrode holder by two holding claws opened and closed by an actuator and releasing the electrode holder from the holding state; and an electrode holder holding device and the electrode holder holding device. And a moving cylinder device that moves between the chucks.

According to a sixth aspect of the present invention, there is provided a small-hole electrical discharge machining method according to the first aspect of the present invention, wherein a plurality of small-diameter machining electrodes are housed one by one from an electrode cartridge accommodating a plurality of small-diameter machining electrodes. Automatic electrode supply device that feeds through to the tip end side and grips the electrode holder attached to the electrode holder chuck at the tip of the machining spindle, and an electrode collection that automatically collects the fine hole machining electrode consumed by electric discharge machining An electrode holder in which a predetermined electrode holder is selected from a plurality of electrode holders accommodated in the device and an electrode holder magazine in a state where the fine hole processing electrode is gripped, and the selected electrode holder is mounted on the electrode holder chuck. An automatic tool electrode changing device is provided to replace the automatic tool supply device, the electrode collecting device, and the automatic tool electrode changing device. And performing by.

According to a seventh aspect of the present invention, there is provided a method for machining a small hole according to a seventh aspect of the present invention. And an automatic electrode supply device that feeds it to the tip side through which the first electrode holder is attached to the electrode holder chuck at the tip of the machining spindle, and automatically collects the fine hole machining electrode consumed by electric discharge machining. A first electrode holder accommodated in the electrode holder magazine without gripping the fine hole machining electrode and a second electrode holder gripped and accommodated in the electrode holder magazine. An automatic tool electrode changing device for selecting an electrode holder and replacing the selected electrode holder with an electrode holder mounted on the electrode holder chuck is provided. The electrode recovery operation and the first electrode holder exchange operation or the second electrode holder exchange operation by the automatic tool electrode exchange device are selectively performed sequentially, and a plurality of small hole electric discharge machining are continuously performed. It is characterized by performing.

Further, according to the eighth aspect of the present invention, in the method for recovering a small hole from the electrode holder, the consumed electrode for a small hole is mounted on the electrode holder chuck. The method is characterized in that it is carried out by removing and transferring to a predetermined position, and storing the electrode for fine hole processing in the electrode collection container at the position.

[0018]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a front view showing the overall schematic configuration of the small hole electric discharge machine of the present invention. In the figure,
1 is a bed of a small hole electric discharge machine,
The saddle 2 and the table 3 whose movements are controlled on the X-axis and the Y-axis orthogonal to each other on the horizontal plane are mounted to form an XY cross table. A processing tank 4 is provided on the table 3, and a workpiece 6 is placed on a surface plate 5 provided at the bottom of the processing tank 4.
Is fixed. A column 7 is erected on the bed 1, and a processing head 8 that is controlled to move up and down in a Z-axis direction (vertical direction) as a main processing axis is provided on the column 7. The processing head 8 is a rotating device such as a servomotor. A machining spindle 10 whose rotation is controlled by 9 is built in. An electrode holder chuck 11 is attached to a tip end (lower end) of the processing spindle 10, and an electrode holder 12 is detachably attached to the chuck 11. 1
Reference numeral 3 denotes an electrode for processing a small hole held by the electrode holder 12, and a pipe electrode having the above outer diameter and length is used as the electrode 13.

Above the machining spindle 10, an electrode cartridge 141 for accommodating a large number of electrodes 13 of a predetermined diameter, and one electrode 13 from the electrode cartridge 141, one for each machining spindle 1.
There is provided an automatic electrode supply device 14 having an electrode feeder device 142 for supplying the distal end side through the hollow portion of O. As the electrode 13 supplied by the automatic electrode supply device 14, usually, of the pipe electrodes having the above outer diameter, φ0.5 m
A pipe electrode of about m or more is used. Details of the automatic electrode supply device 14 will be described later.

As the electrode holder 12, the electrode 13 supplied to the tip side of the machining spindle 10 by the automatic electrode supply device 14 is used.
The first electrode holder 121 for holding the electrode 13 and the second electrode holder 12 for holding an electrode 13 of a different diameter or a different type from the electrode 13 supplied by the automatic electrode supply device 14.
Two types of electrode holders 2 are used, and both are detachably formed on the electrode holder chuck 11. However, while the second electrode holder 122 is attached to and detached from the chuck 11 while holding the electrode 13, the first electrode holder 121
Is different from the second electrode holder 122 in that a part of an automatic electrode gripping and releasing mechanism for automatically gripping and releasing the electrode 13 supplied by the automatic electrode supply device 14 is provided. Reference numeral 15 denotes a nut gripping device that constitutes a part of the automatic electrode gripping release mechanism, and is supported by the processing head 8 and disposed near the electrode holder 12. Details of the automatic electrode grip release mechanism will be described later.

The column 7 is provided with an auxiliary shaft 16 that is controlled to move up and down on a W axis parallel to the Z axis.
In order to prevent deflection of the workpiece 3, a lower guide 17 disposed near the upper surface of the workpiece 6 during processing, and an electrode clamp device 18 including a small open / close actuator and disposed above the lower guide 17 are provided. Are supported by the auxiliary shaft 16. When the first electrode holder 121 holds a predetermined position on the upper end side of the supply electrode 13, the electrode 13 is temporarily fixed and supported by the electrode clamp device 18. In addition, an intermediate guide for preventing deflection of the electrode 13 is provided above the lower guide 17 as necessary.

In the vicinity of the side of the machining head 8, there is provided an automatic tool electrode changing device 19 attached to the bed 1 or the column 7. The automatic tool electrode changing device 19
Is an electrode holder magazine 191 for individually and detachably accommodating a large number of electrode holders, each of which includes the first and second electrode holders 121 and 122, and an electrode holder magazine 191 for connecting the first or second electrode holder to the electrode holder magazine 191. Holder chuck 1
And an electrode holder transfer device 192 for transferring between the two. In addition, an electrode collecting device 20 is provided near the automatic tool electrode changing device 19, and the electrode collecting device 20 includes:
An electrode transfer device 201 for collecting and transferring used electrodes 13 consumed by processing from the first electrode holder 121 mounted on the electrode holder chuck 11 and an electrode collection container 202 for storing the transferred electrodes 13. Have. Then, the electrode holder transfer device 1 of the automatic tool electrode changing device 19
The 92 and the electrode transfer device 201 of the electrode recovery device 20 share the moving cylinder device 21 as a common driving means.

FIG. 2 is an enlarged front sectional view showing the vicinity of the processing head in FIG. 1 in detail. The processing spindle 10 has a cylindrical shape having a hollow portion 101 penetrating in the axial direction at the center,
A pulley 23 provided on the machining spindle 10 and a servo motor 9 are rotatably supported by a bearing 22 in the machining head 8.
Timing belt 25 between pulleys 24 provided on the output shaft of
And the rotation of the motor 9 is transmitted to the machining spindle 10. An electrode holder mounting hole 102 having a larger inner diameter than the hollow portion 101 is formed at the lower end of the processing spindle 10.
A seal member 26 having a through hole vertically penetrating behind the mounting hole 102 is disposed, and the electrode holder 12 is automatically mounted by the electrode holder chuck 11 in a state where the upper portion thereof is inserted and fitted into the mounting hole 102. You. A key 1 of a first electrode holder 121, which will be described later, is provided on the inner periphery of the lower end of the machining spindle 10.
A key groove 103 to be fitted to 21c is formed.

The electrode holder chuck 11 is a known so-called coupler type attachment / detachment device. An attachment / detachment operation member 111 slidably fitted to the outer periphery of the machining spindle 10 and one end thereof is connected to a rod of an air cylinder 113. , The other end is a detachable operation member 1
And a plurality of locking members that fit into holes formed in the peripheral wall near the lower end of the mounting hole 102 so as to disperse and have the same shape. (Steel ball) 112. A large-diameter portion 111
When the attachment / detachment operation member 111 is raised by the operation of the air cylinder 113, the locking member 112 retreats from the hole toward the large-diameter portion 111a, and the electrode holder 12
When the attachment / detachment operation member 111 is lowered, the locking member 112 moves to the large-diameter portion 111a.
Mounting hole 1 which moves inward from above and is loosely fitted in the hole
A part of the electrode holder is protruded from an inner wall of the electrode holder and fitted into an annular groove of the electrode holder to fix and hold the electrode holder.

A hollow cylindrical connecting pipe 27 is connected to the upper end of the machining spindle 10, is rotatably supported by a bearing 22, and rotates integrally with the machining spindle 10. 28 is an O-ring. The upper end of the connecting pipe 27 is a shutter base 2
The hollow 91 of the processing main shaft 10, the hollow 271 of the connecting pipe 27, and the through-hole 291 a of the shutter base 291 coaxially communicate with each other. Reference numeral 292 denotes an air cylinder, and 293 denotes a shutter plate that slides back and forth in the guide hole 291b formed in the shutter base 291 by interrupting the through hole 291a by the operation of the air cylinder 292. The opening / closing device 29 for opening and closing is configured. In the shutter base 291, a machining fluid supply hole 30 is formed so as to communicate with a lower hole of a through hole 291 a that is divided into two parts vertically, and the supplied high-pressure machining fluid is supplied to the connection pipe 27.
Is supplied to the electrode holder 12 through the hollow portion 271, the hollow portion 101 of the machining spindle 10, and the through hole of the seal member 26, and is pressure-fed from the hollow portion of the electrode holder 12 to the hollow portion of the pipe electrode. When supplying the processing liquid (during processing), the shutter plate 293 is advanced by the opening / closing device 29 so that the supply processing liquid does not squirt upward from the through hole 291a.
91a is closed.

On the upper side of the opening / closing device 29, the automatic electrode supply device 14 is mounted on the processing head 8 via the bracket 31 coaxially with the through hole 291a. Automatic electrode supply device 1
Reference numeral 4 denotes a cylindrical electrode cartridge 141 for accommodating a large number of electrodes 13 having a predetermined diameter, and the electrodes 13 in the electrode cartridge 141 are sent out one by one downward, and the machining spindle 10 is passed through the hollow portions 271 and 101 from the through holes 291a. And an electrode feeder device 142 for supplying to the front end side. The electrode feeder 142 has a cylindrical housing 142.
a, a delivery pipe 142b housed in the apparatus a so as to be vertically movable;
It has a compression coil spring 142c that presses the delivery pipe 142b upward, and a pusher lever 142d that moves the delivery pipe 142b downward against the spring 142c.
The electrode cartridge 141 is mounted on the top of the housing 142a coaxially with the pay-out tube 142b.

The feed pipe 142b has a tapered tray 142b1 at the upper end and a large-diameter stepped portion 142b2 at the lower end. The large-diameter stepped portion fits into the recess 142a1 at the lower end of the housing 142a. In addition, payout tube 1
Several slits are formed in the longitudinal direction from the lower end of 42b to the central part, and the operation of the pusher lever 142d lowers the feed pipe 142b to lower the stepped large diameter part 142.
When b2 comes out of the concave portion 142a1, the stepped large-diameter portion 1
42b2 extends outward. Also, it is not clear in the figure,
A stepped small-diameter portion is formed inside the lower part of the feeding pipe 142b, and the stepped small-diameter portion grips the electrode 13 when the stepped large-diameter portion 142b2 is fitted in the concave portion 142a1.

Openings 142a2 are formed on both sides of the housing 142a corresponding to the vertical position of the tray 142b1, and the tip of a pusher lever 142d which moves up and down by a driving device such as an air cylinder is connected to the opening 14a.
2a2 is in contact with the upper end of the tray 142b1. The opening 142a2 is formed to be considerably large on both side surfaces of the housing 142a so as to allow the pusher lever 142d to move up and down and to give a necessary and sufficient vertical movement to the feeding pipe 142b. Further, when machining small holes of different diameters in the workpiece 6, the pusher lever 1
The automatic electrode supply device 14 is attached to the bracket 31 while leaving 42d.
In order to prevent the pusher lever 142d that is not replaced from disturbing the replacement operation when the automatic electrode supply device 14 corresponding to the electrode 13 having a different diameter is removed from the housing 142, the opening 142a2 is formed in the housing 142.
It is formed considerably large on both side surfaces of a.

When a plurality of types of small holes having different diameters are machined in the workpiece 6, as described above, the automatic electrode supply device 14 is removed from the bracket 31 and replaced, leaving the pusher lever 142d. The entirety of the automatic electrode supply device 14 including the
It may be removed and replaced. Also, a plurality of automatic electrode supply devices 14 for supplying electrodes 13 having different predetermined diameters are mounted on an indexing table positioned by a known indexing device.
It is also possible to provide a multi-head type (turret type) automatic electrode supply device 14 in which the automatic electrode supply device 14 capable of supplying the nozzle 3 is automatically positioned at the electrode supply position above the processing spindle. In this case, the indexing table may be a table that moves forward and backward. When the entire automatic electrode supply device 14 is replaced together with the pusher lever 142d in this manner, three openings 142a2 of the housing 142a are formed at intervals of, for example, 120 degrees, and the tips of the pusher levers 142d formed in three parts are separated. Even if it is configured to enter each opening 142a2 and abut on the upper end of the tray 142b1,
There is no hindrance to the replacement work.

A dog 32 is implanted in the pulley 24, and a sensor 33 such as a proximity switch for detecting the dog 32 is provided.
Are provided on the processing head 8. By these, AT
The first electrode holder 121 is moved to the chuck 11 by the C device.
When mounted on the key shaft 103 of the machining spindle 10
The rotation angle position of the machining spindle 10 is indexed at a predetermined angle so as to fit a key 121c of the electrode holder 121 described later. Reference numeral 34 denotes an energizing brush for energizing the rotating electrode 13, and reference numeral 35 denotes a lead wire for supplying machining power to the energizing brush 34.

FIG. 3 is a front sectional view showing the first electrode holder 121. At the upper end of the hollow cylindrical holder body 12B, a fitting hole 121a into which the seal member 26 fits when mounted.
However, a flange portion 121b is provided at the intermediate portion,
A key 121c is provided on the upper surface of the flange 21b.
An annular groove 121d into which the locking member 112 is fitted is formed on the upper side of the first electrode holder 21b, and a male screw 121e is formed on the lower end thereof.
When the upper surface 1b is mounted in the mounting hole 102 by abutting the upper surface of the processing spindle 10 on the lower end surface thereof, the outer shape is tightly fitted in the mounting hole 102. At the time of mounting, the key 12
By fitting 1c into the key groove 103 formed in the processing spindle 10, relative rotation between the first electrode holder 121 and the processing spindle 10 is suppressed.

The holder body 12 of the first electrode holder 121
Inside B, there are a seal holder 121f and a seal 121g.
And a spring collet 121h,
The seal holder 121f and the seal 121g are formed with through holes through which the working liquid and the electrode 13 can pass. 121i
Is a cap nut screwed into the male screw 121e. By tightening the cap nut 121i, the spring collet 121h is tightened, the slit is closed, and the electrode 13 is closed.
And the gap between the seal 121g and the electrode 13 and the inner periphery of the holder main body 12B is sealed. Cap nut 12
On the outer periphery of 1i, a locking groove 121i1 is formed to catch a spanner when rotating and tightening.

The second electrode holder 122 includes a key 121c.
The other configuration is the same as that of the first electrode holder 121 except that the first electrode holder 121 is not provided.
The electrode holder having a seal holder, a seal and a spring collet corresponding to the outer diameter of the electrode 13 to be used can be used for both of the electrode holders. Electrode holder chuck 1
As described above, the electrode holder 12 automatically attached to and detached from the holder 1 is attached to the machining spindle by the engagement member of the steel ball being fitted into the annular groove formed on the outer periphery of the holder main body. When a rotational load is applied, the workpiece can rotate relative to the processing spindle. Therefore, in the first electrode holder, a key 121c that fits into the key groove 103 is provided to prevent the relative rotation, thereby enabling automatic gripping and releasing of the electrode 13 supplied by the automatic electrode supply device. And The second electrode holder is exchanged by the ATC device while the electrode 13 is being gripped. In the case of the small-hole electric discharge machining, a large rotational load does not act at the time of machining, so there is no problem even without the key 121c. Does not occur.

FIG. 4 is a plan view showing the nut gripping device 15 arranged near the electrode holder 12. The nut gripping device 15 includes an open / close actuator (hereinafter, referred to as a hand chuck) 152 operated by an air cylinder 151.
A locking claw 153 that engages with the locking groove 121i1 of the cap nut 121i. When the processing spindle 10 is rotated to cause the first electrode holder 121 to grip or release the electrode 13, a hand is used. The chuck 152 is operated, the locking claw 153 is hooked on the locking groove 121i1, and the cap nut 121i is gripped and fixed. By rotating the holder body 12B together with the processing spindle 10 in the fixed state to tighten or loosen the cap nut 121i, the slit of the spring collet 121h is opened and closed, and the electrode 13 is gripped and released. The keyway 103 at the lower end of the processing spindle 10, the key 121c of the first electrode holder 121, and the nut gripping device 15 constitute the automatic electrode gripping release mechanism.

Next, the automatic tool electrode changing device (ATC device) 19 and the electrode collecting device 20 will be described in detail.
FIG. 5 shows a machining head 8, AT of a small-hole electric discharge machine according to the present invention.
FIG. 2 is a plan view showing a C device 19 and an electrode recovery device 20;
FIG. 6 shows that the electrode holder 12 of the processing shaft 10 is
FIG. 7 is a front view showing a case in which only the electrode 13 consumed by processing is collected by the electrode collecting device 20. The electrode holder magazine 191 of the ATC device 19 includes a circular magazine table 191a that is rotationally controlled so as to be indexable, and the table 191a.
Accommodation members 191b arranged at predetermined intervals on the outer periphery of
Consists of A large number of storage members 191b are
91a is formed in a U-shape that opens outward in the radial direction.
The electrode holder 12 (first or second electrode holder) is housed and supported in the U-shaped recess. A leaf spring or the like is arranged so as to surround the U-shaped recess so that the stored electrode holder 12 does not fall off.

A moving cylinder device (air cylinder) 21 is provided below the table 191a, and an arm 21b is attached to a tip of a rod 21a of the air cylinder 21. The arm 21b is provided with two upper and lower gripping devices. Both gripping devices move forward and backward by the operation of the air cylinder 21. The upper gripping device is an electrode holder gripping device 192a in which a known hand chuck is attached with an electrode holder gripping claw having a concave portion that grips the electrode holder 12 when closed. An electrode gripping device 201a is provided with an electrode gripping claw having a flat contact surface that grips the electrode 13 when closed, on a hand chuck. The electrode holder transfer device 192 is constituted by the electrode holder holding device 192a and the moving cylinder device 21, and the electrode holding device 201a and the moving cylinder device 2
1 constitutes an electrode transfer device 201. The moving cylinder device 21 is also used as a driving unit of the electrode holder transferring device 192 and the electrode transferring device 201.

As shown in FIG. 7, the first electrode holder 12
A holding plate 36 having a groove 361 to be fitted to the key 121c is attached to the housing member 191b for housing the key 1c. When the first electrode holder 121 is transferred from the magazine 191 to the chuck 11 by the electrode holder transfer device 192, the key 121c is moved to the key groove 10 of the machining spindle 10.
When the first electrode holder 121 is housed in the housing member 191b in advance so as to face a certain direction just fitting with the third electrode holder 121,
The groove 361 guides the key 121c and aligns the holder 121 in a certain direction. Preferably, a key detection sensor for confirming the presence of the key 121c is provided near the groove 361. Usually, since the first electrode holder is rarely used in many kinds, the first electrode holder provided with the backing plate 36 is used.
It is sufficient to provide several electrode holder housing members 191b. By providing the key detection sensor, it is possible to confirm that the first electrode holder is securely housed in the specific housing member and to confirm that the key is set in the correct direction. Can be controlled.

The electrode collecting device 20 includes the electrode transfer device 2
01, an air cylinder 203 attached to a support or a bed or a column of the ATC device 19, and its rod 2
And an electrode collection container 202 fixed to the electrode collection container 03a. When the electrode gripping device 201a grips the consumable electrode and returns to the retracted position, the electrode collection container 202 moves forward by the operation of the air cylinder 203, and the collection container 202 accommodates the consumable electrode that is released and dropped by the electrode gripping device 201a. And collect.
A cutout 202a is formed in the electrode collection container 202 to allow the consumable electrode to enter the container when the electrode collection container 202 moves forward (see FIGS. 5 and 7). After collecting the consumable electrode, the electrode collection container 202 retreats to the retracted position, and the stroke of the air cylinder 203 is set so that the electrode collection container 202 does not interfere with the electrode holder or the like mounted on the ATC device at the retreated position. You.

Next, the ATC device 19 uses the electrode holder 1
An electrode holder replacing operation for mounting the electrode holder 2 on the electrode holder chuck 11 will be described. The exchange operation by the ATC device is basically the same as in the prior art. That is, the worker
The electrode 13 having a predetermined diameter required for the small hole electric discharge machining is held in the second electrode holder 122, and the holder 122 is stored in advance in the storage member 191b of the ATC device. When replacing the electrode holder, the control device rotates the magazine table 191a to move the second electrode holder 122 holding the electrode 13 used for processing to a position (ATC replacement position) facing the electrode holder holding device 192a. At this time, both gripping devices 192a and 201a are in a state where the gripping claws are opened. Next, the gripping device 192a closes the gripping claws to grip the holder 122, moves forward by the operation of the air cylinder 21, and transfers the holder 122 directly below the electrode holder chuck 11.
Next, the controller prepares the electrode holder exchange preparation position (X
The machining spindle 10 already positioned at the YZ coordinate position) is lowered to the electrode holder exchange position, and the electrode holder 122 is moved to the mounting hole 10 of the machining spindle.
Insert into 2. At this time, the attachment / detachment operation member 1 of the chuck 11
11 is raised and the locking member (steel ball) 112 retreats outward and is not restrained, so that the electrode holder 122 is inserted into the mounting hole 102 without resistance. Next, the control device lowers the attachment / detachment operation member 111, fits the steel ball 112 into the annular groove 121d to fix and hold the electrode holder 122, and then opens the gripping claws of the gripping device 192a to remove the device 192a. Retreat. In this manner, the second electrode holder 122 holding the electrode 13 is mounted on the machining spindle 10, and the fine hole electric discharge machining is started.

After the processing, the operation of replacing the electrode holder 12 with the next electrode holder 12 is performed in a manner reverse to the above. That is, after positioning the processing spindle 10 at the electrode holder replacement position, the control device advances the gripping device 192a, closes the gripping claws, and grips the electrode holder. Next, the attachment / detachment operation member 111 of the electrode holder chuck 11 is raised to release the grip of the electrode holder, and the machining spindle 10 is raised to the electrode holder replacement preparation position. Then, the gripping device 192a is moved to the retreat limit position, and the transferred electrode holder is stored in the housing member 1 of the ATC device 19.
Transfer to 91b. Thereafter, a new electrode holder is selected from the electrode holder magazine 191 and mounted on the processing spindle by the above-described operation.

In this embodiment, the electrode holder 12 is AT
The rod 21a of the air cylinder 21 is at the position of the retreat limit when being stored or removed from the storage member 191b of the C device 19, and at this position, the pair of gripping claws of the gripping device 192a open and close by 90 degrees each. Since the accommodating member 191b is formed in a U-shape that opens outward, the electrode holder 12 and the gripping device 1 can be moved only by such an operation.
92a. Further, since the magazine table 191a has a relatively large disk shape and the electrode holder mounted on the outer periphery of the table 191a in the same shape as that of the table 191a is small, even if the table 191a turns, the open gripping claws and the electrode holder may interfere. I will not do it.

On the other hand, when the electrode holder 12 is attached to and detached from the electrode holder chuck 11, the rod 21a of the air cylinder 21 is at the limit of the forward movement.
The pair of gripping claws 2a opens and closes. As described above, since the air cylinder 21 only needs to reciprocate between the two positions of the forward limit and the backward limit, the configuration and control of the electrode holder transfer device 192 are extremely simple. Thus, the electrode holder transfer device 1
It is preferable that the moving distance of the rod 92 coincides with the stroke of the rod 21a, but the distance may be adjusted by regulating the position with two stopper members.

Next, the first electrode holder 121 is mounted on the processing spindle 10 by the ATC device 19, and
The operation of supplying the electrode 13 to the device and causing it to be gripped will be described. The operator has previously received the storage member 19 having the backing plate 36.
The first electrode holder is stored in 1b. At this time, the key 121c is stored facing the groove 361. On the other hand, the electrode 13 having a predetermined diameter required for processing is stored in the electrode cartridge 141 of the automatic electrode supply device 14. When the multi-head type automatic electrode supply device is provided, the electrode cartridge 141 containing the electrode 13 having a predetermined diameter is controlled by the control device.
It is indexed on the machining spindle 10. First, the first electrode holder 121 corresponding to the diameter of the electrode 13 to be used is mounted on the electrode holder chuck 11 by the ATC device 19. The operation at this time conforms to the above-described operation of attaching the second electrode holder to the electrode holder chuck 11 by the ATC device 19, but in the case of the first electrode holder, the machining spindle 1
0 so that the key groove 103 is located at an angular position to be fitted to the key 121c of the first electrode holder to be mounted.
A rotation angle position of 0 is determined. This operation is performed by rotating the machining spindle 10 to a position where the sensor 33 detects the dog 32 of the pulley 24 and stopping and holding the machining spindle at the angular position. The work spindle 10 thus prepared is lowered in the same manner as described above, and the first electrode holder 121 is moved.
At this time, the key 121 of the electrode holder 121 is attached.
c is fitted into the key groove 103 of the machining spindle 10 and is mounted in a state where mutual rotation is stopped.

After the first electrode holder 121 is mounted on the processing spindle 10, the electrodes 13 are supplied by the automatic electrode supply device 14. This supply operation is similar to the operation of feeding a refill in a so-called knock mechanical pencil. First, the processing head 8 is lowered until the first electrode holder 121 is located near the lower guide 17 disposed close to the workpiece 6. Then, after the cap nut 121i is gripped and fixed by the nut gripper 15, the processing spindle 10 is rotated, and the collet 121h and the seal 121g are rotated.
The cap nut 121i is loosened so that the electrode 13 passes through the through hole. Next, the air cylinder 292 is operated, the shutter plate 293 is retracted to open the through hole 291a, and then the pusher lever 142d is moved up and down to send one electrode 13 downward to move the electrode 13 downward to the upper surface of the workpiece 6. Abut.

The operation of feeding the electrode 13 at this time is performed as follows. The pusher lever 142d pushes down the feed pipe 142b until the stepped large diameter portion 142b2 at the lower end of the feed pipe 142b comes out of the concave portion 142a1 at the lower end of the housing 142a. With this, the feeding pipe 1
The lower portion of 42b expands, and one electrode 13 is fed out of the electrode cartridge 141 and falls into the tube 142b.
Next, when the pusher lever 142d rises, the delivery pipe 142b is pushed upward by the compression coil spring 142c, the large-diameter stepped portion 142b2 fits into the concave portion 142a1, the slit closes and the electrode 13 is gripped. By repeating this operation, the electrode 13 is gradually extended downward. In this operation, when one electrode 13 comes into contact with the workpiece 6, the upper end of the electrode 13 is left in the feeding tube 142 b.

Next, the electrode 13 is connected to the electrode clamping device 18.
After that, the pusher lever 142d descends to release the grip of the electrode 13 by the feeding tube 142b. When the processing head 8 is raised by a predetermined amount in this state, the upper end of the electrode 13 is relatively lowered. Then, when the upper end of the electrode 13 reaches a position where it comes out from the lower end of the feeding tube 142b, the processing head 8 stops, and the pusher lever 142
d rises to feed out the subsequent electrode 13 and the tube 142b grips it. Subsequently, the processing head 8 is further raised, and when the electrode 13 reaches a position where the electrode 13 protrudes from the lower end of the first electrode holder 121 by a predetermined amount, the processing head 8 stops again. Then, the processing spindle 10 is rotated, the cap nut 121i is tightened, and the electrode 13 is gripped. Next, the locking claw 153 of the nut gripping device 15 is opened to release the gripping and fixing of the cap nut 121i, and the electrode clamp device 18 is opened to release the gripping of the tip of the electrode 13, and the shutter plate 293 of the opening / closing device 29 is opened. To close the through hole 291a. Thus, the operation of supplying the electrode 13 to the first electrode holder 121 and gripping it is completed.

The operation of recovering the electrode 13 consumed by the electric discharge machining by the electrode recovery device is performed as follows. First, while moving the machining spindle 10 to the electrode replacement position,
The operation of the air cylinder 21 causes the two gripping devices 192a and 201a to move forward to be positioned below the electrode holder chuck 11 (at this time, the gripping claws of both gripping devices are open). Thereafter, the gripping claws of the electrode gripping device 201a are closed to grip the consumable electrode 13. Next, with the cap nut 121i held and fixed by the nut holding device 15, the processing spindle is rotated in the reverse direction to loosen the cap nut 121i, and the consumable electrode 13 is released from being held by the first electrode holder 121. Subsequently, the processing spindle 10 (the first electrode holder 12)
1) is raised to the electrode replacement preparation position, and after the consumable electrode 13 is pulled out from the holder 121, the air cylinder 21 is operated to close the electrode holder gripping device 192a with the gripping claws opened and the gripping claws closed. The electrode holding device 201a holding the consumable electrode 13 is retracted to the original position. Then
The operation of the air cylinder 203 causes the electrode collection container 202 to advance, and causes the consumable electrode 13 to enter the container 202 from the notch 202a. Then, the electrode gripping device 201a
Is released, and the consumable electrode 13 is removed from the electrode collection container 20.
2 and is stored. Finally, the electrode collection container 202 containing the consumable electrode 13 is retracted to the original position by the operation of the air cylinder 203, and the operation of collecting the electrodes is completed.

After the consumable electrode 13 is collected, a new electrode 13 is supplied to the first electrode holder 121 by the automatic electrode supply device 14 and is gripped. This operation is performed in the same manner as the above-described electrode supply operation. However, in order to position the first electrode holder 121 close to the lower guide 17, an operation of lowering the processing spindle 10 (the processing head 8) at the electrode replacement preparation position again is added first, and at this time, the operation is already performed. Since the cap nut 121i is loosened, the operation of loosening the cap nut 121i is omitted. Thus, each time the electrode 13 is consumed, the first electrode holder 121 is used.
, The consumable electrode 13 is collected, a new electrode 13 is supplied, and the fine hole electric discharge machining is continued.

When the electrode 13 is supplied one after another using the automatic electrode supply device 14 to perform the processing, and then the normal electrode holder exchange is performed by the ATC device 19, the processing is performed first.
After the first electrode holder 121 is returned to the electrode holder magazine 191 of the ATC device, the second electrode holder 122 is attached to the processing spindle 10. This operation is performed except that the rotation angle position (the position of the key groove 103) of the processing spindle 10 is determined by the dog 32 and the sensor 33 when the first electrode holder 121 is returned to the electrode holder magazine 191. This is no different from the electrode holder exchange operation by the ATC device described above.

[0050]

According to the present invention, every time the fine hole machining electrode is consumed by machining, the consumable electrode is automatically collected by the electrode collecting device, and a large number of small hole machining electrodes having a predetermined diameter are stored. An automatic electrode supply device having an electrode cartridge, a small hole electric discharge machining is performed while supplying new electrodes of a predetermined diameter one by one to the electrode holder one by one, and the electrode holder attached to the machining spindle is rotated by an ATC device. A single-hole electric discharge machine that performs a small-hole electric discharge machining while automatically exchanging with a proper electrode holder among a plurality of electrode holders holding different-diameter small-hole machining electrodes, respectively. Therefore, even when a large number of small holes with a single diameter are sequentially processed, or when a large number of small holes with a different diameter are sequentially processed, or a combination of these processes is continuously performed. Can respond to To improve the operating rate, the versatility of the small hole electric discharge machine.

Further, when the electrode for processing a fine hole supplied by the automatic electrode supply device is taken out of the electrode holder magazine by the ATC device and is held by the first electrode holder attached to the processing spindle, the processing is performed again. When the electrode for a small hole processing consumed by the above is automatically recovered from the first electrode holder by the electrode recovery device, the cap nut of the first electrode holder attached to the processing main shaft so as to be unable to rotate relative to the processing spindle is connected to the nut. With a simple operation of rotating the processing spindle while being gripped and fixed by the gripping device, the fine hole drilling electrode can be easily and reliably attached to and detached from the first electrode holder. In addition, the relative rotation of the machining spindle and the first electrode holder is suppressed by providing a key on the first electrode holder and forming a key groove on the machining spindle to fit the key. In combination with the reversing operation of the main shaft, the operation of tightening and loosening the electrodes can be performed, and the automatic electrode gripping and releasing mechanism can be easily configured.

Further, since the electrode holder transfer device of the ATC device and the electrode transfer device of the electrode recovery device are driven by the same driving means (moving cylinder), an electrode holder exchange function by the ATC device and an automatic electrode Even if the electrode exchange function provided by the supply device and the electrode recovery device is combined, the configuration relating to the electrode exchange is not complicated, and the control thereof is easy. In addition, the electrode for drilling small holes consumed by
Since the electrode is collected from the machining spindle by the electrode transfer device of the TC device and transferred, and then stored in the electrode collection container, the electrode collection device is not complicated and its control is easy.

Further, if the automatic electrode supply device is a multi-head type automatic electrode supply device capable of supplying several kinds of electrodes for processing small holes, the operating rate and versatility are further improved.

Further, the rotation angle position of the key of the first electrode holder is regulated to a predetermined position in the electrode holder magazine of the ATC device, and the rotation angle position of the key groove formed at the tip of the machining spindle is adjusted to the predetermined position. The first electrode holder can be replaced by the ATC device by arranging the first electrode holder so as to match the position.

[Brief description of the drawings]

FIG. 1 is a front view showing the overall schematic configuration of a small-hole electric discharge machine according to the present invention.

FIG. 2 is an enlarged front sectional view showing the periphery of a machining head of the small hole electric discharge machine according to the present invention.

FIG. 3 is a front sectional view showing a first electrode holder of the present invention.

FIG. 4 is a plan view showing a nut holding device of the present invention.

FIG. 5 is a plan view showing a machining head, an automatic tool electrode changing device, and an electrode collecting device of the small hole electric discharge machine according to the present invention.

FIG. 6 is a front view showing a case where a second electrode holder is replaced by the automatic tool electrode changing device of the present invention.

FIG. 7 is a front view showing a case where an electrode is collected by the electrode collection device of the present invention.

[Explanation of symbols]

1 Bed 2 Saddle 3 Table 4 Processing tank 5 Surface plate 6 Workpiece 7 Column 8 Processing head 9 Rotating device 10 Processing spindle 101 Hollow section 102 Electrode holder mounting hole 103 Key groove 11 Electrode holder chuck 111 Removable operation member 111a Large diameter section 112 Locking member (steel ball) 113 Air cylinder 114 Lever 12 Electrode holder 12B Holder main body 121 First electrode holder 121a Fitting hole 121b Flange part 121c Key 121d Annular groove 121e Male screw 121f Seal press 121g Seal 121h Spring collet 121i Cap nut 121i1 Locking groove 122 Second electrode holder 13 Electrode for fine hole processing 14 Automatic electrode supply device 141 Electrode cartridge 142 Electrode feeder device 142a Housing 142a1 Recess 142a2 Opening 1 2b Feeding pipe 142b1 Receiving tray 142b2 Stepped large diameter portion 142c Compression coil spring 142d Pusher lever 15 Nut gripper 151 Air cylinder 152 Openable actuator (hand chuck) 153 Locking claw 16 Auxiliary shaft 17 Lower guide 18 Electrode clamp device 19 Automatic tool Electrode exchange device (ATC device) 191 Electrode holder magazine 191a Magazine table 191b Housing member 192 Electrode holder transfer device 192a Electrode holder gripping device 20 Electrode collection device 201 Electrode transfer device 201a Electrode gripping device 202 Electrode collection container 202a Notch 203 Air cylinder 203a rod 21 moving cylinder device 21a rod 21b arm 22 bearing 23 pulley 24 pulley 25 timing belt 26 sealing member 27 connecting pipe 71 hollow portion 28 O-ring 29 switchgear 291 shutter base 291a through hole 291b hole 292 air cylinder 293 shutter plate 30 working-fluid supply holes 31 bracket 32 dogs 33 sensor 34 energized brush 35 lead 36 caul 361 grooves

Claims (8)

[Claims] An electrode for machining a fine hole in the form of a thin wire or a thin rod is opposed to a workpiece through a discharge gap, and a machining fluid is supplied to the discharge gap. An intermittent voltage pulse is applied in between to generate a discharge pulse repeatedly, and a relative machining feed in the opposite direction is given between the two to provide a small-hole electric discharge machine that forms a small hole in a workpiece. An electrode holder chuck which is provided at the tip of a machining spindle whose rotation is controlled, and which automatically attaches and detaches an electrode holder; an electrode cartridge which accommodates a large number of fine hole machining electrodes having a predetermined diameter;
An electrode feeder device for supplying the fine hole processing electrodes one by one from the electrode cartridge to the distal end side through the hollow portion of the processing spindle, and an automatic electrode supply device provided above the processing spindle; and the electrode holder chuck. A first electrode holder formed so that it can be automatically attached and detached by the first electrode holder and capable of gripping the fine hole machining electrode; the first electrode holder attached to the electrode holder chuck, and the automatic electrode supply device. An automatic electrode gripping and releasing mechanism that enables automatic gripping and release from the gripping state of the fine hole processing electrode supplied to the distal end side of the processing spindle; and automatic detachment by the electrode holder chuck. A second electrode holder formed and gripping the fine hole machining electrode different from the fine hole machining electrode; and the first and second electrode holders are individually and detachably housed. A possible electrode holder magazine, and an electrode holder transfer device for transferring the first or second electrode holder between the electrode holder magazine and the electrode holder chuck, wherein the electrode holder magazine is mounted on the electrode holder chuck. An automatic tool electrode changing device for replacing a first or second electrode holder with a predetermined first or second electrode holder in the electrode holder magazine; and the first electrode holder mounted on the electrode holder chuck. An electrode transfer device that collects and transfers the predetermined-diameter fine-hole processing electrode from the electrode, and an electrode collection container that stores the predetermined-diameter fine-hole processing electrode transferred by the electrode transfer device. And a small hole electrical discharge machine. 2. The method according to claim 1, wherein the first electrode holder has a spring collet capable of gripping the small-diameter hole processing electrode having a predetermined diameter, and a tightening nut for tightening the spring collet.
The automatic electrode gripping and releasing mechanism includes a key formed on the first electrode holder and a tip of the machining spindle so as to fit with the key in a state where the first electrode holder is mounted on the electrode holder chuck. The key groove formed and a nut gripper for gripping the tightening nut, and the automatic gripping and release from the gripping state of the narrow hole processing electrode having the predetermined diameter is performed by the nut gripper by the nut gripper. The small-hole electrical discharge machine according to claim 1, wherein the machining is performed by rotating the machining spindle while holding the workpiece. 3. The thin electrode according to claim 1, wherein the electrode holder transferring device of the automatic tool electrode changing device and the electrode transferring device of the electrode collecting device are driven by the same driving means. Hole electric discharge machine. 4. An automatic electrode supply apparatus comprising: a plurality of electrode cartridges each accommodating an electrode for machining a small hole having a predetermined diameter different from each other; and a plurality of electrode feeders corresponding to the plurality of electrode cartridges. The apparatus is mounted on an indexing table positioned by an indexing apparatus, and the electrode cartridge accommodating an electrode for processing a fine hole having a desired diameter, and the electrode feeder apparatus corresponding to the electrode cartridge, 2. The small-hole electric discharge machine according to claim 1, wherein the multi-head type automatic electrode supply device is positionable at an electrode supply position above a machining spindle. 5. The electrode holder magazine of the automatic tool electrode changing device, wherein accommodating members capable of individually and detachably accommodating the first and second electrode holders are provided at predetermined intervals on an endless rotating member. An electrode holder holding device for holding the first or second electrode holder from two gripping claws opened and closed by an actuator, and releasing the electrode holder holding device from the holding state; 2. The small-hole electric discharge machine according to claim 1, comprising a member and a moving cylinder device for moving between the electrode holder chucks. 6. A fine wire or fine rod-shaped fine hole machining electrode is opposed to a workpiece through a discharge gap, and the machining liquid is supplied to the discharge gap. An intermittent voltage pulse is applied in between to generate a repetitive discharge pulse, and at the same time, a relative machining feed in the opposite direction is given between the two, thereby forming a small hole in a workpiece in small hole electric discharge machining. Then, from the electrode cartridge accommodating a large number of fine hole processing electrodes having a predetermined diameter, the fine hole processing electrodes are supplied one by one through the hollow portion of the processing spindle to the distal end side, and the electrode holder chuck at the distal end of the processing spindle is supplied. An automatic electrode supply device that allows the electrode holder in the mounted state to be gripped, an electrode recovery device that automatically recovers the fine hole processing electrode consumed by electric discharge machining, and a state in which the fine hole processing electrode is gripped in the electrode holder magazine Multiple housed electrode holders Select a predetermined electrode holder from the
An automatic tool electrode changing device for exchanging the selected electrode holder with an electrode holder attached to the electrode holder chuck is provided, and each of the automatic electrode supply device, the electrode collecting device, and the automatic tool electrode changing device is provided. A thin hole electrical discharge machining method characterized in that a plurality of small electrical discharge machines are continuously operated by selectively operating them. 7. A fine wire or fine rod-shaped fine hole machining electrode is opposed to a workpiece through a discharge gap, and the machining liquid is supplied to the discharge gap. An intermittent voltage pulse is applied in between to generate a repetitive discharge pulse, and at the same time, a relative machining feed in the opposite direction is given between the two, thereby forming a small hole in a workpiece in small hole electric discharge machining. Then, from the electrode cartridge accommodating a large number of fine hole processing electrodes having a predetermined diameter, the fine hole processing electrodes are supplied one by one through the hollow portion of the processing spindle to the distal end side, and the electrode holder chuck at the distal end of the processing spindle is supplied. An automatic electrode supply device that allows the first electrode holder in a mounted state to be gripped, an electrode recovery device that automatically recovers the fine hole processing electrode that has been consumed by electric discharge machining, and a fine hole processing electrode that is gripped by the electrode holder magazine. Not accommodated in the first Automatically selecting a predetermined electrode holder from the electrode holder and the second electrode holder that holds and holds the fine hole processing electrode, and replaces the selected electrode holder with an electrode holder attached to the electrode holder chuck. A tool electrode exchange device, an electrode supply operation by the automatic electrode supply device, an electrode collection operation by the electrode collection device, and an exchange operation of the first electrode holder or the second electrode by the automatic tool electrode exchange device. A thin hole electrical discharge machining method characterized in that a plurality of small electrical discharge machining operations are successively performed by selectively performing each operation of a holder replacing operation sequentially. 8. The collecting of the fine hole machining electrode by the electrode collecting device is such that the exhausted fine hole machining electrode is removed from the electrode holder attached to the electrode holder chuck and transferred to a predetermined position. The method according to claim 6, wherein the method is performed by storing the electrode for machining a small hole in an electrode collection container.