JPS63162122A - Manufacture of electrode guide for electric discharge process device - Google Patents

Abstract

PURPOSE:To easily manufacture a flexible electrode guide with a high degree of accuracy by securing a microparticle coating layer made of hard materials, on the outer surface of a core member so as to form a stock of an electrode guide, by processing the external shape of the stock to remove the core member and by lapping the bore of the guide. CONSTITUTION:A coating layer 52a made of diamond microparticles is formed on the outer surface of an aluminum core member 53 over a length of (l) through the intermediary of an adhesive film 54. The outer surface of the core member 53 is subjected to application of electrical conductivity over a length slightly longer than that of an electrode guide while the remaining part is coated thereon with an insulating film, Further, an electro-deposition layer is successively accumulated on the outer surface of the coating layer 52a so as to form a stock of the electrode guide. Further, the external shape of the stock is processed coaxially with the core member 53 so as to radially form four axial grooves, and thereafter the core member 53 is removed. After insertion of a thin lapping wire, lapping is made while a lapping powder such as diamond or the like is fed so as to complete the electrode guide. Thus, it is possible to easily manufacture flexible electrode guides capable of expecting electric discharge processing with a high degree of accuracy.

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention provides a method of applying a discharge voltage to a wire-shaped electrode by running it in the longitudinal direction to generate an electric discharge between the wire-shaped electrode and the workpiece. , regarding a method for manufacturing an electrode guide constituting an electrode holder used in a wire-cut electric discharge machining device for machining a workpiece, and in particular, a method for manufacturing an electrode guide that is formed to bulge inward and support an electrode when fluid pressure is applied. The present invention relates to a method of manufacturing a flexible electrode guide.

[Conventional technology]

Generally, in wire cut electrical discharge machining equipment.

The wire-shaped electrode to which a discharge voltage is applied is caused to run in the longitudinal direction, and electric discharge is generated between the wire-shaped electrode and the workpiece, thereby cutting the workpiece, for example. In this case, it is necessary to apply tension to the wire-shaped electrode by applying tension to the wire-like electrode, for example, at the upper and lower portions thereof, using guide rollers or tension rollers, and to hold the wire-like electrode by a guide in order to maintain the relative position with respect to the workpiece. The most common conventional guide has a configuration as shown in FIG. 10, for example. In the figure, reference numeral 1 denotes a holder, which is formed into a hollow cylindrical shape and has a tapered or trumpet-shaped end face with a large inner diameter. A guide member 2 is made of a hard material such as diamond and has a hollow cylindrical shape, and is fitted into the holder 1. The guide member 2 must be able to pass through the wire-shaped electrode 3 and run freely in the longitudinal direction, and at the same time must be restrained from moving in the direction perpendicular to the axis. It is formed.

[Problem that the invention seeks to solve]

In the above-mentioned conventional guide, it is necessary to form the gap [)>d, but in the method of automatically connecting the wire-shaped electrode 3, it is necessary to form the gap formed by (D-d) significantly larger. Therefore, the restraint of the wire-shaped electrode 3 is reduced, and the processing accuracy is reduced.

Further, since the supporting portion of the wire-like electrode 3 is close to a point, the amplitude due to the i-motion becomes large, and the radius of curvature ρ of the supporting portion of the wire-like electrode 3 of the guide member 2 is small.

Deformation may occur in the wire-shaped electrode 3 due to work hardening.

There is a problem that processing accuracy is further reduced.

In order to solve these problems and significantly improve processing accuracy, the present applicant is simultaneously applying for a patent for an improved invention. FIG. 8 is a longitudinal cross-sectional view showing the embodiment, and FIG. 9 is a cross-sectional view taken along the line A--A in FIG. In both figures, a guide 5 is made of a strong material such as spring steel and has a hollow cylindrical shape, with a through hole 6 provided in the center.

The inner diameter of the through hole 6 is smaller than the outer diameter of the wire electrode 3 by 2, for example, 5.
The two-wire electrode 3 is formed to have a size of ~50 μm and can run in the direction of the arrow. Next, the inner surface of the through hole 6 is coated with a hard material to form the electrode holding part 7. Inside the guide 5, a plurality of pressure chambers 9 are provided radially between the guide 5 and the electrode holding portion 7 with pressure partition walls 8 interposed therebetween. Next, reference numeral 10 denotes a guide holder, which is formed into a hollow cylindrical shape and is fitted and integrated with the guide 5. The inner surface of the guide holder 10 has an annular groove facing each of the plurality of pressure chambers 9. At the same time, at least one communication port 12 is provided and opened on the outer periphery. Reference numeral 13 denotes a holder, which is disposed so as to fit with the outer circumferential surface of the guide holder 10, and has a through hole 14 in the center thereof, and a holder 9 that faces into the through hole 14 and comes into contact with the surface of the wire-shaped electrode 30. A conductor 15 is provided at the terminal. A communication port 16 is provided in the holder 13, one end of which communicates with the communication port 12, and the other end open to the outside of the holder 13.

It is connected to a pressure fluid source via a control device (none of which is shown) so that pressure can be applied and released. 17 is a connection pipe. Further, the holder 13 is provided with a communication port 18 that opens upward, so that machining fluid can be supplied through a pipe 19. Next, a screw 20 is cut into the outer periphery of the holder 13, and a nozzle 22 having a through hole 21 in the center is screwed therein. A communication port 23 is provided in the nozzle 22 to allow the processing liquid to flow therethrough. 24 is a workpiece.

With the above configuration, the holding action of the wire-shaped electrode during primary electric discharge machining will be described. First, Figures 8 and 9
In the figure, the wire-shaped electrode 3 is inserted into the through hole 6 of the guide 5, and one electron 15 is brought into contact with the surface of the wire-shaped electrode 3. The pressure chamber 9 is then connected to the pressure chamber 9 by means of the communication port 16.
If fluid is introduced into the interior and fluid pressure is applied, the pressure partition 8
Since it elastically deforms inward and bulges out, the wire-shaped electrode 3 can be held via the electrode holding part 7.

Among the members constituting the electrode holder, it can be used as a guide. However, for guide 5, 9 e.g. 0
．． It has an inner diameter of 0.03 to 0.4 mm and includes a through hole 6 having a relatively large axial length.

This is because it is necessary to bulge the electrode holding portion 7 inward.

Flexibility must be imparted, and there is a problem in that it is usually impossible to manufacture only by mechanical processing or one means, or manufacturing is extremely complicated.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems and provide a method for easily manufacturing the above-mentioned flexible electrode guide.

[Means for solving problems] The present invention aims to solve the above problems.

A. In a method for manufacturing a flexible electrode guide constituting an electrode holder that holds a wire-shaped electrode so as to be freely movable in the longitudinal direction for an electric discharge machining device that performs machining by electric discharge between the workpiece and the workpiece.

B. A step of forming a material for the electrode guide by adhering a coating layer of fine particles made of a hard material to the surface of the core material in which the guide hole through which the wire-shaped electrode is to be penetrated is to be formed.

Process of processing C0 material.

D. Step of removing the core material.

They adopted technical means to include the following.

〔Example〕

FIG. 1 (al) is a vertical cross-sectional view and a cross-sectional view, respectively, showing an example of the electrode guide that is the object of the present invention.

This corresponds to the guide 5 in FIGS. 8 and 9 above.

In both figures, the electrode guide 5a is formed into a hollow cylindrical body with a slightly larger diameter at both ends, and four radial grooves 51 are provided in the axial direction on the outer periphery. When assembled as an electrode holder, this groove 51 forms a part of the pressure chamber 9 as shown in FIGS. 8 and 9. Numeral 52 is a fine particle made of a hard material such as diamond, and is disposed facing the inner surface of the first through hole 6. Note that the inner diameter of the through hole 6 is a minute size, such as a diameter of 0.25 m5.

Next, Example 1 of the method for manufacturing the electrode guide 5a described above.
This will be explained with drawings. FIG. 2 (al(b)) is a partially sectional front view and a cross sectional view showing the preparation state of the core material in the embodiment of the present invention. First, a core material 53 made of aluminum and having a diameter of 0.2 mm, for example, is prepared. Axial path MI on the surface!
A thin film 5 made of adhesive is formed in the range of
A coating layer 52a of diamond fine particles 52 is provided through the diamond particles 4. In addition, when providing the covering layer 52a, the method shown in FIG. 2 (
As shown in the cross section in bl, a radial gap 55 with a width of 9 and a dimension of e is provided.

For example, four pieces are arranged at equal intervals. Next, the surface of the core material 53 including the coating layer 52a is subjected to a treatment for imparting electrical conductivity, for example, by a silver mirror reaction method such as a dipping method.

The conductivity imparting treatment range, that is, the axial length is set to be slightly larger than the axial length of the electrode guide 5a shown in FIG. 1. An insulating film (56 in FIG. 3) is applied to the other portions of the core material 53.

FIG. 3 is a longitudinal cross-sectional view of a main part showing an example of an electroforming device. In the same figure, inside a tank 31 formed into two cylindrical shapes, an anode electrode 32 formed into a hollow cylindrical shape is disposed approximately coaxially with the tank 31, and a circulation system 34 with a pump 33 interposed therein is provided. The electroforming bath 35 housed in the tank 31 is circulated. 36 is a DC power supply, one end of which is connected to the anode pole 32.
At the same time, the other end is connected to the conductive portion of the core material 53 prepared as described above to form a cathode. 38 is a heater. As described above, the electroformed layer 37 is successively accumulated on the surface of the coating layer 52a of the core material 53, and a material for an electrode guide having a cross-sectional external dimension of about 1 square can be formed. When the electroforming layer 37 is formed by nickel electroforming, the electroforming bath 35 may be, for example, a nickel chloride bath (nickel chloride 300 g/l, ferrous acid 30 g/1.p).
II 2) was injected, the bath temperature was maintained at 50-70°C,
When the electroforming bath 35 is circulated in the direction of the arrow by the operation of the circulation system 34, which is done by adjusting the voltage of the DC power supply 36 so that the current density is 2.5 to IOA/dm, the electroformed layer 37 is uniformly formed. Effective for forming thick layers.

Next, FIG. 4, FIG. 5(a), and FIG. 6 are longitudinal cross-sectional views showing the processed state of the material, respectively, and FIG. 5(middle) is a cross-sectional view of FIG. 5(a). First, in FIG. 4, the outer shape of the material 40 is processed coaxially with the core material 53 using a cutting tool 41, for example.

Next, as shown in FIG. 5, four axial grooves 51 are provided radially on the outer circumference of the material 40, and then the core material 53 is removed.

In the case of removing the core material 53, for example, a hole is formed in the core material 53 using a fine electrical discharge machine, the core material 53 is dissolved by dipping in a caustic soda solution, or a combination of both methods is used. There is. FIG. 6 shows the ramp processing state of the through hole 6 formed by removing the core material 53.
The fine wire 42 for lapping is inserted into the through hole 6 and is reciprocated in the axial direction while supplying rough powder 43 such as diamond. FIG. 7 is a partially enlarged sectional view showing the inner surface of the through hole 6 after lamp processing. As shown in the figure, the surface of the electroformed layer 37 is polished by 5 dimensions more than the surface of the diamond particles 52 by the lamp processing, so that the hard particles 52 are exposed to the inner surface of the second through hole 6. is formed, and the electrode electrode is completed.

In this example, the case where the constituent material of the core material in which the through hole of the electrode guide is formed is an aluminum round bar, but the constituent material of the core material may be other metals or alloys other than aluminum, wax, or plastic. It may also be a non-metallic material such as.

In addition, the cross-sectional shape of the core material is not limited to a circle, and may be any other geometric shape (including a hollow pipe), and the external dimensions are approximately within the range of 0.03 to 0.4 mm. Of course, it can be used. Further, in connection with the above, the cross-sectional shape of the electrode guide can also be selected to be a shape other than circular. Furthermore, as a material for forming the coating layer.

In addition to diamond, ceramics and other hard and/or wear-resistant materials can be used. Note that as the electroforming bath, a bath containing other metals can be selected, and the electroforming apparatus is not limited to that shown in this embodiment. Further, as a means for removing the core material, not only chemical dissolution but also thermal dissolution or heating combustion means, a combination thereof, and a combination of these and mechanical perforation means can be used. It goes without saying that the order of the steps described above for manufacturing the electrode guide can be partially changed depending on the situation. Further, the step of fixing a coating layer of fine particles made of a hard material to form the material of the electrode guide is performed by integrating the steps of the above embodiments and using, for example, an electroforming bath in which fine particles made of a hard material are suspended. .

The hard fine particle coating layer may be formed together with the electroformed layer.

〔Effect of the invention〕

Since the present invention has the structure and operation as described above,
It has the effect of making it possible to easily and accurately manufacture a flexible electric drilling guide that can be used for high-precision electrical discharge machining.

[Brief explanation of the drawing]

Fig. 1 (al fb) is a longitudinal sectional view and a transverse sectional view showing an example of the electrode guide which is the subject of the present invention, and Fig. 2 fa
t(b) is a partially sectional front view and a cross sectional view showing the prepared state of the core material in the embodiment of the present invention, FIG. 3 is a vertical sectional view of the main part showing an example of the same electroforming apparatus, and FIG. . Figures 5(a) and 6 are longitudinal cross-sectional views showing the processing state of the same material, respectively. Figure 5(a) is a cross-sectional view of Figure 5 (al). Figure 7 is a partial enlargement of Figure 6 8 is a vertical sectional view showing an example of an improved electrode holder, FIG. 9 is a sectional view taken along line A-A in FIG. 8, and FIG. 3: Wire-shaped electrode, 5 Ni guide, 5a: Electrode guide, 6
: Through hole, 7: Electrode holding part, 37: Electroformed layer, 40: Material, 51: Groove, 52a: Covering layer. 53: Core material. Patent applicant: Discharge Precision Machining Research Institute Co., Ltd. Representative Patent Attorney Hiroshi Morita (3 others) Bian 1 Figure (a) (b) 2 m (a) (b)-3 Figure 4 Figure fJ 5 Whisper 6 m

Claims (1)

[Claims] In a method for manufacturing a flexible electrode guide constituting an electrode holder that holds a wire-shaped electrode for an electric discharge machining device that performs machining by electric discharge between a workpiece and a workpiece so as to be freely movable in the longitudinal direction,
A step of forming a material for an electrode guide by adhering a coating layer of fine particles made of a hard material to the surface of a core material in which a guide hole through which a wire-like electrode is to be passed, a step of processing the material, and removing the core material. 1. A method of manufacturing an electrode guide for electrical discharge machining equipment, the method comprising the step of: