JPH0459090B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a wire electrical discharge machining apparatus, and particularly to the structure of its wire guide device.

[Conventional technology]

FIG. 3 is an explanatory diagram of a wire guide of a conventional wire electric discharge machining apparatus. In the figure, 1 is a wire electrode, 5 is a die guide for guiding the wire electrode 1, and a hole 5a is provided in the center with a taper that spreads upward and downward. Usually 5~ than the diameter d ₁ of electrode 1
The wire electrode 1 can be inserted into the die guide 5 by increasing the diameter by about 20μ.

A conventional wire electric discharge machining apparatus is provided with a wire guide as described above and performs wire electric discharge machining.

[Problem that the invention seeks to solve]

In the die guide 5 of the conventional wire electric discharge machining apparatus as described above, if the difference between the inner diameter d of the hole 5a of the die guide 5 and the diameter d1 of the wire electrode ₁ becomes large,
Although the ease of inserting the wire electrode 1 into the hole 5a is improved,
Instead, the restraint of the wire electrode 1 becomes worse. Due to the poor restraint, the deflection of the wire electrode 1 in the processing area increases, and depending on the direction of progress of the processing, the position of the wire electrode 1 changes, resulting in a significant decrease in processing accuracy.

On the other hand, to reduce the difference between the inner diameter d of the hole 5a of the die guide 5 and the diameter _d1 of the wire electrode 1, the wire electrode 1 is inserted into the hole 5a of the die guide 5 by an automatic wire feeder (not shown). This is difficult because it is necessary to ensure good insertability.

Furthermore, when using wire electrodes 1 of different diameters, it is necessary to replace the die guide 5 with a die guide 5 having a hole d corresponding to each different diameter. There were various problems such as a decrease in machining accuracy due to displacement of the restraint position.

[Means for solving problems]

The wire electrical discharge machining apparatus according to the present invention includes a die guide receiving part having a penetrating part whose cross section is tapered around the wire electrode, and a supporting part supporting a compression spring at the lower part of the penetrating part, and a die guide receiving part having a supporting part for supporting a compression spring. It is installed corresponding to the tapered penetration part,
A die guide section that moves vertically along the tapered surface of the through section to contract and expand with respect to the center of the wire electrode by pressurization and depressurization from one direction; touched,
a die guide position adjustment section that adjusts the position of the die guide section; and a wire guide that is provided in the die guide section and guides the wire electrode by concentrically colliding with the wire electrode as the die guide contracts and expands. It has a section.

[Effect]

In this invention, since the guide hole of the die guide part that guides the wire electrode can be adjusted by expanding or contracting concentrically, the wire electrode can be accurately positioned at the same position in response to changes in the diameter of the wire electrode. It will be kept at.

〔Example〕

FIG. 1 is a cross-sectional view of a wire guide device which is a main part of the present invention. In the figure, 1 is a wire electrode similar to the conventional device described above, 2 is a workpiece through which the wire electrode 1 is passed, and 10 is the entire wire guide device. 20 is a die receiver with a T-shaped cross section, and a tapered hole 21 is provided in the center of the die receiver.
A hole 22 is provided in communication with the hole 21, and a hole 24 is provided in communication with the support portion 23 formed so as to protrude inwardly. Reference numeral 25 denotes an inlet for the machining fluid 4 provided on the side surface of the die holder 20. An L-shaped passage 26 for the machining fluid 4 is provided from the inlet 25, and an opening 26 is formed in the upper part of the die holder 20. 27 is a screw formed on the outer circumferential surface of the die receiver 20, and 28 is a protruding piece having a hole 28a formed on the outer surface of the die receiver 20.

Reference numeral 30 denotes a die guide section having a collet structure, and a wire guide section 31 for guiding the wire electrode 1 is provided in the upper opening. Further, the hole 30a of the wire guide portion 31 is tapered to facilitate receiving the wire electrode 1.

The die guide portion 30 is formed such that its outer peripheral surface is aligned with the hole 21 of the die holder 20, and is attached to the hole 21 of the die holder 20. 32 is the die guide part 30 and the die holder 2
This is a compression spring installed between the support part 23 of 0 and the support part 23 of 0.

Reference numeral 40 denotes a nozzle screwed onto the screw 27 of the die holder 20. A hole 41 is provided in the center of the nozzle, and a gear 43 is provided on the outer peripheral surface of the piece 42 that protrudes around the lower end.
The gear 43 meshes with a pinion 44 and is rotated by the motor 9 provided on the protruding piece 28 of the die holder 20. Reference numeral 46 denotes a holding part provided on the nozzle 40, which holds the nozzle 40 against the die holder 20.
When the screws 27 and 45 are screwed together and moved downward, the presser part 20 is moved to the die guide part 30.
is pressed down to compress the compression spring 32.

Reference numeral 50 denotes a power supply die provided in the hole 24 of the die receiver 20, and a current is passed from the machining power source 3 to the wire electrode 1 via the workpiece 2 and the power supply die 50.

2A and 2B are a plan view and a side view of the die guide section 30. In this way, the die guide part 3
0 has slots 30b arranged radially around the hole 30b to form a collect structure.
By tightening the tapered portion of the die guide portion 30, the diameter d of the hole 30a through which the wire electrode 1 passes can be expanded or reduced concentrically with the wide tapered portion.

Wire guide device 10 configured as above
When inserting the wire electrode 1 into the wire guide part 31 from above (in FIG. 1) through the hole 2a of the workpiece 2 and the hole 41 of the nozzle 40, first drive the motor 9 and The nozzle 40 is rotated and moved upward, and the die guide section 30 is moved upward by the compression spring 32. Since the die guide section 30 has a collet structure, the diameter of the hole 30a of the wire guide section 31 can be easily adjusted. Expanding.

Next, insert the wire electrode 1 into the hole 3 of the wire guide part 31.
Insert it into 0a, extend it downward, and insert it into die receiver 2.
0. Contact the power supply die 50 provided at 0. When the insertion operation of the wire electrode 1 is completed, the motor 9 is driven and the nozzle 40 is rotated and moved downward via the pinion 44.
presses down the die guide section 30, so
The diameter of the hole 30a of the wire guide part 31 is the same as that of the wire electrode 1.
The diameter should be the minimum that suppresses vibration and reduces positional deviation. In practice, this minimum diameter is the wire electrode 1
A diameter of about +0 to 5 μ is preferable for accuracy. Also, the pitch of the screws 45 and 27 of the nozzle 40 and the die holder 20, the gear ratio of the gear 43 and the pinion 44, the pushing amount of the die guide part 30 into the hole 21 of the die holder 20, and the diameter of the hole 30a of the wire guide part 31. Since the amount of reduction is relative, it is only necessary to control the motor 9 so that it can be driven to a predetermined value determined based on these amounts.

Furthermore, as shown in FIG.
Electric discharge machining is performed while feeding the wire from above to below, and when the wire electrode 1 is consumed due to the discharge and its diameter becomes smaller, the diameter of the hole 30a of the wire guide section 31 is reduced by the same operation as explained above. Therefore, the diameter of the hole 31a of the wire guide portion 31 can be set so that the wire electrode 1 does not vibrate or shift, and the conditions are optimal for electrical discharge machining.

Furthermore, even if the wire electrode wears out during electrical discharge machining and its diameter becomes smaller, the wire guide section 3 does not interrupt machining and responds to changes in electrical discharge machining conditions.
By continuously changing the number of holes 30a, it is possible to maintain optimal conditions for electrical discharge machining.

The diameter of the hole 30a of the wire guide section 31 is adjusted to be reduced in this manner not only when the diameter is reduced due to the discharge of the wire electrode 1 as described above, but also when the wire guide section 31 itself is exposed to electric contact. Therefore, it goes without saying that adjustments can be made even when the diameter is reduced.

In the description of the above embodiment, the material of the wire guide part 31 is not specified in particular, but it may be made of hard material such as sapphire, diamond, or ceramics such as zirconia or silicon nitride, etc.
By bonding a material with excellent electrical insulation properties to the surface of the wire guide section 31, it is possible to prevent electrical contact wear and extend the life of the wire guide section 31. Furthermore, in the above embodiment, the wire guide section 31 is provided in the die guide section 30 of the collect mechanism to adjust the diameter of the hole 30 of the wire guide section 31, but the diameter of the hole 30a of the wire guide section 31 may be enlarged. Alternatively, if there is a function to reduce the size, other means may be used, such as changing the inner diameter of the die guide portion concentrically using a scroll chuck.

Furthermore, in the above embodiment, the wire guide device 1
Although the case where the wire guide device 10 is located below the workpiece 2 has been described, the purpose can be achieved in the same way even when the wire guide device 10 is located above the workpiece 2.

Furthermore, if the wire guide part 31 is not made of an insulating material as described above, but is made of a material with good electrical conductivity and high hardness, and the contact surface area with the wire electrode 1 is increased, the wire Guide part 31
can have the function of guiding the wire electrode 1 at the same time as supplying power to the wire electrode 1, and with this configuration, electrical contact of the wire guide portion 31 can be reduced.

〔Effect of the invention〕

As explained above, the present invention moves the die guide part in the vertical direction along the tapered surface of the die guide receiving part, and as the die guide part shrinks and expands due to the movement, the die guide part is provided with the die guide part. Since the wire guide portion concentrically contacts the wire electrode, the wire electrode is stably guided without vibration or displacement, and highly accurate machining can be provided.

Furthermore, by enlarging the diameter of the die guide portion, insertion of the wire electrode in the initial state can be facilitated.

In addition, since the diameter of the wire guide part can be adjusted even if the diameter of the wire electrode is different, it is possible to adapt the wire guide part with one die, and the work of exchanging the die can be omitted and the work efficiency can be improved. Further, since the position of the wire electrode can be precisely maintained at all times, electrical discharge machining can be performed with high performance and high precision. Furthermore, even if the wire electrode is consumed and its diameter becomes smaller due to electrical discharge machining, the diameter of the guide hole can be changed to accommodate the reduced diameter, so high-precision machining can be performed. Furthermore, even if the amount of wear of the wire electrode varies depending on the conditions of electrical discharge machining, it is possible to perform electrical discharge machining with high precision and high efficiency by minimizing the positional shift of the wire electrode without interrupting machining. There is an effect.

[Brief explanation of the drawing]

Figure 1 is a sectional view of the wire guide device which is the main part of this invention, Figures 2A and B are a plan view and side view of the die guide section in Figure 1, and Figure 3 is an explanation of a conventional wire guide. be. In the figure, 1 is a wire electrode, 2 is a workpiece,
10 is the entire wire guide device, 20 is a die holder, 21 is a tapered hole, 22 and 24 are holes, 2
3 is a support part, 25 is a machining fluid inlet, 27 and 45 are screws, 30 is a die guide part, 31 is a wire guide part, 32 is a compression spring, 40 is a nozzle, 43 is a gear, 44 is a pinion, and 50 is a power supply It's dice.
In each figure, the same reference numerals indicate the same or corresponding parts.

Claims (1)

[Scope of Claims] 1. A die guide receiving part having a tapered penetrating part whose cross section is narrowed toward the center with the wire electrode at the center, and a supporting part supporting a compression spring at the lower part thereof; It is mounted in correspondence with the tapered penetration part of the guide receiving part, and is moved vertically along the tapered surface of the penetration part by pressurization and depressurization from one direction, and is reduced relative to the center part of the wire electrode. and a die guide section that expands; a die guide position adjustment section that comes into contact with the upper part of the die guide section and adjusts the position of the die guide section; and a die guide position adjustment section that is provided on the die guide section and that adjusts the size and size of the die guide. A wire electrical discharge machining apparatus comprising: a wire guide portion that concentrically contacts and guides the wire electrode. 2. The wire guide according to claim 1, wherein the portion of the wire guide portion that comes into contact with the wire electrode is made of a highly hard and insulating material such as sapphire, diamond, ceramics, silicon nitride, and zirconia. Wire electrical discharge machining equipment.