JP4928184B2 - Wire positioning device - Google Patents

Description

In the present invention, the positioning device in the wire electrode travel path in the electric discharge machining by the wire electric discharge machine makes it possible to maintain the wear resistance even in the use over time, and the machining accuracy is maintained precisely, and the wear resistance The present invention relates to a wire positioning device that enables cost reduction required for maintenance.

In electric discharge machining using a wire electric discharge machine, wires that serve as electrodes that travel and move at a predetermined tension and speed are opposed to each other by a minute interval (interval that can be discharged) to a workpiece that is processed and fed by an XY axis plane. The pair of wire positioning devices are sent to the travel route by accurate positioning. In this specification, the term “wire” is used as a synonym for an electrode wire or a wire electrode, and the term “wire positioning device” is used to mean at least a device having a function of positioning a wire. Yes. Since the wire positioning device can be positioned in the vicinity of the occurrence of the discharge phenomenon between the workpiece and the wire, heat resistance is required, and the guide surface of the wire is made electrically insulating.

In the taper machining of the workpiece, the wire electrode tilting mechanism moves the wire positioning device to a deviation coordinate position suitable for taper machining to tilt the wire to an angle suitable for taper machining and perform electric discharge machining. In this case, even if a slight amount of wear occurs in the wire guide portion of the wire positioning device, the wire inclination angle decreases from the initial set value, and an error occurs in the taper angle. An error occurs, and the processing accuracy is significantly reduced.
Therefore, in the past, with the intention of improving wear resistance and maintaining / improving processing dimensions and processing accuracy, the shape and structure of the guide portion are V-groove guide, V-flat guide, die-shaped guide, rod-shaped or There are proposals for various contents such as a guide portion in which a plurality of guide pieces such as V-grooves are arranged (see, for example, Patent Document 1).
As for the material of the guide portion, various kinds of cemented carbide materials such as iron-based alloys, cemented carbides, ceramics, ruby, CBN, and diamond have been proposed due to the demand for wear resistance (for example, Patent Documents). 1).
By the way, in the case of a split guide, forming a pair of guide main bodies with diamond is difficult to manufacture and costs enormously (see Patent Document 2 for an overview of split guides). Moreover, about the insertion hole and the insertion hole, a semicircular insertion hole and an insertion hole (a semicircular male side and a female side) are formed, a pair of guide bodies are attached, and a semicircular shape It is very difficult to make the insertion holes without shifting in terms of production and other points. Therefore, the conventional split guide is generally manufactured with sapphire or the like which is easy to manufacture and others, and when using diamond, it is the limit to use it by covering the guide surface ( For example, see Patent Document 1).

Patent Document 1 JP 11-262820 Patent Document 2 Utility Model Registration No. 2512551

Various problems such as the following (1) to (6) existed with respect to the guide surface of the superhard material (for example, ceramics, diamond, etc.) and the device structure in the conventional wire positioning device.
(1) Diamond coating by the plasma CVD method (the same applies to the coating method by microwave plasma CVD) is a method in which an object is heated to a high temperature (generally 700 to 1, 100 ° C.) in a sealed container under a low pressure (6 to 60 Torr). (Ii) to form a polycrystalline diamond coating film, there is a problem that there are significant restrictions on the shape and material of the guide surface.
(2) Diamond coating by the plasma CVD method has a problem that it is difficult to use iron-based metal on the target guide surface because it is difficult to grow on the iron-based metal.
(3) With diamond coating by plasma CVD, the film thickness is limited to the range of 1 to 50 μm and the surface roughness is about 2 to 5 μm Rmax. There was a problem that it was necessary to grind with diamond powder.
(4) Since the diamond coating film is thin, deviation due to wear occurs. Therefore, there is a problem that it is necessary to replace the covered guide portion before the deviation occurs.
(5) The replacement of the coated guide part has a problem that it is necessary to accurately detect the progress of wear of the coating film and to determine the guide part replacement time from the detection information (for example, see Patent Document 1). reference). (6) The means for detecting the progress of wear of the coating film has to be provided with complicated mechanical and electrical control means, and there is a problem that the structure of the wire positioning device becomes complicated (for example, patents) See references 1 and 2.)

Therefore, in the present invention, high accuracy and long life were studied by making the entire guide portion diamond and splitting the entire device, and the wire positioning device according to the present invention was invented.
(I) An object of the present invention is to provide a wire positioning device that enables accurate and precise positioning of a wire and improves wear resistance accuracy and processing accuracy.
(Ii) It is another object of the present invention to provide a wire positioning device having a guide portion having a through hole for positioning with high wear resistance and high accuracy and a minute diameter.
(Iii) It is another object of the present invention to provide a wire positioning device that includes a guide portion and can be manufactured at a reduced cost.
(Iv) It is another object of the present invention to provide a wire positioning device in which the entire device and the internal structure have a degree of design freedom.

A wire positioning device according to the present invention has a pair of block-shaped split molds of a guide main body , and a split part of a storage part and a guide part of the storage unit that collide with the split molds. The through hole of the diamond tip of the part is formed in the same vertical direction,
(1) The block-shaped split mold of the guide main body has a concave storage section on the bottom plane in a planar shape extending from the mating section to the back,
(2) The block-shaped split mold of the introduction part has a planar shape that can be fitted into the concave storage part of the guide main body part, and its peripheral surface is fitted and fixed to the concave storage part,
(3) The diamond chip split mold is fixed to the edge of the plate-like holding part, and through holes of the diamond chip are formed by the split mold contact,
(4) The plate-shaped holding part has a reverse tapered planar shape that fits into the concave storage part, and has a structure in which the plate surface is fixed to the bottom flat surface of the concave storage part of the guide main body part. It is characterized by.

According to the wire positioning device of the present invention, effects represented by the following (1) to (6) and the like can be obtained.
(1) Since the positioning through-hole has high wear resistance and is controlled with high precision and a very small diameter by the diamond tip in the guide part, the wire can be positioned accurately and precisely in the travel path. Accuracy is improved and the life of the wire positioning device is extended.
(2) Since the guide body has a structure in which an insertion hole and a through-hole are formed in the longitudinal direction of the abutting part by the collision of the internal structure by the collision with the mating guide body, the split guide is made of diamond. As a result, the usefulness, operability, handleability, and productivity as an industrial device are significantly improved as compared to the split guide of the diamond coating film.
(3) Even if the guide part is made entirely of diamond, there is no restriction due to thickness, and it is sufficient that the abutment of the diamond tip is larger than the wire diameter (mostly 0.8 mm or less). The required cost is lower than that of the plasma CVD diamond coating film. (4) Since the guide part is due to the abutment of the diamond tip, drilling is performed with the laser at the abutting part of the single crystal diamond tip to eliminate the deviation of the through hole, and the formation of a through hole with a remarkably high hole diameter can be formed. It becomes possible.
(5) Since the split mold of the guide body part is configured as a block body, the split mold of the introduction part is made into a block shape, and the diamond tip is fixed on the plate surface of the plate-like holding part. There is a degree of freedom in design.
(6) Since the diamond tip is held by the plate-like holding portion, it is easy to eliminate the gap between the attachment portions and match the semicircular through holes.

BEST MODE FOR CARRYING OUT THE INVENTION The best mode for carrying out a wire positioning device according to the present invention will be specifically described with reference to FIGS.
FIG. 1 is a perspective view illustrating a state in which the wire positioning device is divided into guide main body portions and the internal structure thereof is also disassembled. FIG. 2 is a perspective view showing a state in which a pair of guide main body portions can collide with each other. FIG. 3 is a perspective view showing a wire positioning device in which a pair of guide main body portions and the internal structure thereof are abutted with each other. In addition, the same code | symbol in each figure has shown the same or equivalent thing.

< Outline of wire positioning device >:
By the abutment by the wire positioning device 1 and the block-shaped split guide main body parts 2 and 2a, the split mold of the internal structure is abutted to form the introduction part and the guide part, and the insertion part and the through hole are formed in the abutting part. Is formed.
Since the guide portion of the wire positioning device 1 is formed by a pair of diamond tips (particularly, a fine single crystal diamond tip), a diamond tip processing method (for example, a laser processing method) can be used. It is possible to form a positioning through hole with improved positioning performance by processing the mating portion. Next, the wire positioning device will be specifically described by dividing it into a guide main body portion, an introduction portion, and a guide portion.

< Guide body >:
The guide main body parts 2 and 2a are divided into block-shaped split molds having a rectangular or approximate plane from a structural material having heat resistance, conductivity and mechanical strength, and split between the split molds 3 and 3a of the introduction section and the guide sections. The mold (diamond chips 4 and 4a) is stored in the storage part, and the stored split mold is also contacted by the abutment of the guide main body parts 2 and 2a, and the insertion hole 7 and the through hole 8 are formed in the abutting part. It has a structure.
That is, the guide main body parts 2 and 2a are divided so that the abutment parts of the split molds 3 and 3a of the introduction part and the split molds of the guide part (diamond tips 4 and 4a) are located on the same vertical surface. , 3a, 4 and 4a are stored in the concave storage portions 6 and 6a.
The guide main body parts 2 and 2a are plates that hold the split molds 3 and 3a and the diamond chips 4 and 4a in order to form the insertion holes 7 and the through holes 8 with high hole accuracy at the introduction part and the joining part of the guide part. The planar shape of the concave holding portions 5 and 5a and the planar shape of the concave storage portions 6 and 6a can be fitted, and the inner wall surface of the concave storage portions 6 and 6a is connected to the outer peripheral surface of the split molds 3 and 3a of the introduction portion. Close adhesion is possible. The bottom surfaces of the concave storage portions 6 and 6a can be closely fixed to the plate surfaces of the plate-like holding portions 5 and 5a.

The concave storage parts 6 and 6a are formed in a planar shape extending from the mating part of the guide body parts 2 and 2a to the back, and are fitted and fixed to the split molds 3 and 3a and the plate-like holding parts 5 and 5a in the horizontal direction. The fine movement is also avoided. The guide body parts 2 and 2a are a combination of a male type and a female type with a tapered surface, so that errors due to misalignment are eliminated.
In use, the guide main body portions 2 and 2a are attached to the guide assembly with bolts or pins using bolt holes.

The constituent materials of the guide main body parts 2 and 2a are metal (for example, stainless steel, cemented carbide) and ceramics. As the ceramic, a conductive material (for example, silicon carbide) provided with conductivity by mixing a metal and other conductive material (for example, TiC, TiN, BN, etc.) can be used.

< Introduction >:
The introduction part is configured by a pair of block-shaped split molds 3 and 3a, and has a structure in which an insertion hole 7 is formed in the abutting part. The block-shaped split molds 3 and 3a have a planar shape that can be fitted into the concave storage portions 6 and 6a of the guide main body portions 2 and 2a, and are fitted into the concave storage portions 6 and 6a. It is positioned at a predetermined position by the convex positioning member 10 on the inner wall surface of 6 and 6a and the concave positioning member 11 on the peripheral surface of the block-shaped split molds 3 and 3a, and is fitted and fixed.
The block-shaped split molds 3 and 3a of the introduction part are high enough to allow the insertion hole 7 to be formed, and do not cause a fine effect on the hole accuracy of the insertion hole 7 due to frictional friction of the wire running in tension. Now, it is formed in a size that can be stored in the concave storage parts 6 and 6a of the guide body parts 2 and 2a, and the shape and size can be changed depending on the mechanical strength and hardness of the material. is there.

The insertion hole 7 of the introduction part has a function of introducing a wire serving as an electrode of the wire electric discharge machine and guiding it to the guide parts 4 and 4a, so that the opening part into which the wire is introduced is large at the outlet. In the insertion hole 7 of the introduction part, for example, the opening part may be the same shape or approximate shape as the truncated cone surface, and the outlet may be a truncated part.
Further, since the insertion hole 7 of the introduction part has a function of guiding the introduced wire to the through hole of the guide part, it is desirable that the outlet of the insertion hole 7 is in the vicinity of the entrance of the through hole of the guide part. However, the communication between the insertion hole 7 and the through hole 8 and the arrangement with a distance are also possible.

Further, the outlet of the insertion hole 7 of the introduction part is located immediately above the inlet of the through hole of the guide part, and the centers of the insertion hole 7 and the through hole 8 pass through the same linear axis.
The introduction part has a function as a lid that guides the wire tip to the through hole of the guide part, maintains the dimensional accuracy of the large-shaped insertion hole 7, and protects the guide part of the diamond. Ceramics (for example, zirconia or the like) are desirable.

< Diamond guide section >:
In the guide portion, a through hole for guiding and positioning a wire (mostly 0.7 mm or less in diameter) serving as an electrode is provided in an abutting portion at the abutting of a pair of diamond tips. Since the diamond tip only needs to be larger than the wire diameter, it can be a fine diamond, and a single crystal diamond tip can be used from the viewpoint of wear resistance and the like. When a pair of single crystal diamond tips are put together and a through hole is drilled by laser processing at the mating portion and lapped, it is possible to form a guide portion composed of a single crystal diamond tip having a through hole with high hole accuracy. Become.

The diamond tips 4 and 4a in which half of the through-holes with high hole accuracy (that is, semicircular through-holes) are formed are fixed to the attachment portions at the end portions on the abutting side of the plate-like holding portions 5 and 5a. . The plate-like holding parts 5 and 5a are fixed to each other by screws so that the plate surfaces are in close contact with the bottom planes of the concave storage parts 6 and 6a of the guide main body parts 2 and 2a. The fixing of the plate-like holding parts 5 and 5a to the bottom plane of the concave storage parts 6 and 6a of the guide main body parts 2 and 2a can be another fixing means capable of fine adjustment of the fixing state.
In this way, the diamond tips 4 and 4a are held by the plate-like holding portions 5 and 5a, and the fixing state is finely adjusted by screws or the like. A complete circular through-hole with no gap is formed in the diamond. That is, the core of the wire positioning split guide is diamond-shaped.
The diamond tips 4 and 4a can be fixed to the attachment portions of the plate-like holding portions 5 and 5a by any means as long as it can be reliably fixed. The diamond chips 4 and 4a are fixed by adjusting the gap between the diamond chips 4 and 4a at the abutting portion.
The plate-like holding parts 5 and 5a have a planar shape (so-called reverse taper shape) that can be fitted into the concave storage parts 6 and 6a. The plate-shaped holding portions 5 and 5a and the split molds 3 and 3a of the introduction portion having the same planar shape are stored in the concave storage portions 6 and 6a so that the abutting portions are positioned in the same vertical direction. As a result, even when the diamond chips 4 and 4a are brought into contact with each other, no extremely fine deviation occurs. The guide part is composed of a single crystal diamond chip and is fixed via the plate-like holding parts 5 and 5a, and the plate-like holding parts 5 and 5a are fitted into the concave storage parts 6 and 6a of the guide main body parts 2 and 2a. By joining and adhering, the wire positioning device according to the present invention has the characteristics shown in the following column.

First, the through-hole 8 of the guide part is formed in diamond with high hole accuracy, thereby enabling accurate and high-precision positioning of the wire.
Second, since the positioning through-hole 8 is formed from the diamond tips 4 and 4a, it has high wear resistance, and high wear resistance is maintained through electric discharge machining.
Thirdly, it is possible to form the through hole 8 without a gap between the diamond chips 4 and 4a.
Fourth, since the diamond tips 4 and 4a are fixed via the plate-like holding portions 5 and 5a, no error occurs in the accuracy of the through-holes even if a wire having tension is brought into frictional contact.
Fifth, the plate-like holding parts 5 and 5a are inserted into the concave housing parts 6 and 6a of the guide main body parts 2 and 2a and the positioning of the guide parts is accurately performed by interposing a fixing means using bolts. The hole accuracy of the hole 8 can be maintained.

<Wire EDM>
The wire electric discharge machine and electric discharge machining provided with the wire positioning device of the present invention are not particularly limited and can be of any type and form. Accordingly, when the wire is tilted at a predetermined angle by the wire electrode tilting mechanism and the electric discharge machining is performed, the wire positioning device can be controlled and moved.

With the wire positioning device of the present invention, it becomes possible to maintain high wear resistance and high processing accuracy over time of use of electrode wires in a wire electric discharge machine, and facilitate operations required for installation, assembly, disassembly, etc. .

It is a disassembled perspective view of a pair of guide main-body part. It is a perspective view which shows the state assembled to a pair of guide main-body part. It is a perspective view which shows the wire positioning device by the abutting of a pair of guide main-body part.

Explanation of symbols

1 Wire positioning device
2 Guide body
2a Guide body
3 Block type of introduction part
3a Block type of introduction part
Four
Diamond tip
4a diamond tip
5 Plate holder
5a Plate-shaped holding part
6 Concave storage
6a concave storage
7 Insertion hole
8 through hole
10 Convex positioning tool
11 Concave positioning tool

Claims (2)

A pair of block-shaped split molds of the guide main body part, and a split part of the storage part and guide part of the storage are abutted with the split molds, and an insertion hole of the introduction part and a diamond chip through hole of the guide part Are formed in the same vertical direction,
(1) The block-shaped split mold of the guide main body has a concave storage section on the bottom plane in a planar shape extending from the mating section to the back,
(2) The block-shaped split mold of the introduction part has a planar shape that can be fitted into the concave storage part of the guide main body part, and its peripheral surface is fitted and fixed to the concave storage part,
(3) The diamond chip split mold is fixed to the edge of the plate-like holding part, and through holes of the diamond chip are formed by the split mold contact,
(4) The plate-shaped holding part has a reverse tapered planar shape that fits into the concave storage part, and has a structure in which the plate surface is fixed to the bottom flat surface of the concave storage part of the guide main body part. A wire positioning device characterized by the above. 2. The wire positioning device according to claim 1 , wherein the pair of diamond chips is made of a single crystal diamond chip, and an abutting portion of the pair of diamond chips is laser processed into a through hole. .