JPS6328520A - Manufacture of electric discharge machining electrode for forming honeycomb die - Google Patents

Abstract

PURPOSE:To make it possible to cut forming grooves in a honeycomb die machining electrode with a high degree of accuracy, by carrying out a prefinishing step of cutting grooves in a predetermined part of an electrode block formed in a predetermined shape, and a finishing step of setting a plate thickness to planar projection electrode parts. CONSTITUTION:Parallel grooves or first prefinishing groves 4, 4... are previously formed at predetermined pitches P1 in an electrode block 1' which is formed from a graphite material by forming the latter into a block-like shape. The width d1 of the grooves 4 and the pictures P1 are previously determined in accordance with the shape and dimensions of a honeycomb body, and the depth of the grooves corresponds to the height H of projection electrode parts 3. Then second prefinishing grooves 5, 5... having predetermined pitches P2 and a predetermined width of d2 are formed in a zigzag pattern, orthogonal to the first prefinishing grooves 4, 4. After completion of the prefinishing step, a finishing step of cutting finishing grooves 6, 6... having predetermined pictures P3 and a predetermined width d3, orthogonal to the first prefinishing grooves 4, 4 is carried out to produce an electrode. Thus, it is possible to simply produce a honeycomb forming electric discharge machining electrode of the unit structure with a high degree of accuracy.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention relates to a method for manufacturing an electric discharge machining electrode for forming a honeycomb die, particularly for a honeycomb die in which a desired regular hexagonal forming groove is formed in a mesh pattern. A method for manufacturing an electrical discharge machining electrode in which plate-shaped protruding electrode portions corresponding to one side of the regular hexagonal forming groove are arranged in a staggered manner, the method comprising: manufacturing the above-mentioned electrical discharge machining electrode from a block-shaped electrode material pre-formed into a predetermined shape; The present invention relates to a method of manufacturing an electric discharge machining electrode for honeycomb die forming, in which an electric discharge machining electrode having an integral structure is manufactured by cutting out a protruding electrode portion.

(Prior Art) A honeycomb die as shown in FIG. 9 has been known as an extrusion die for forming a honeycomb body having a regular hexagonal surface shape. In addition, FIG. 9(A) is a front front view,
FIG. 9(B) is a rear view, and FIG. 9(C) is a sectional view taken along arrow A-A in the figure.

Reference numeral 15 in the figure indicates a honeycomb casing, which includes a forming groove 16 bored in a shape corresponding to the cross-sectional shape of the honeycomb body to be formed; It has a hole 17. In addition.

Reference numeral 18 represents an intersection.

The forming grooves 16 of the honeycomb die 15 are generally formed by electrical discharge machining. That is, for example, a graphite electric discharge machining electrode (hereinafter referred to as an electrode) having a shape corresponding to the honeycomb body to be formed, or a metal electrode 21 or 21 as shown in FIG. 10 (A) or (B). This is done by electric discharge machining using 25. However, in general, the mesh shape (regular hexagon in the present invention) constituting a honeycomb body has, for example, a side length of about 2 mm and a wall thickness of about 0 mm.
There was a problem in that it was difficult to manufacture electrodes with high precision because the electrodes were as small as 2 m. Also, the first
The electrodes 21 to 24 shown in Figure 0 are usually manufactured by pressing a copper plate, for example, but this is not preferred because the bent portions become rounded.

Furthermore, since the thickness is very thin, there is an undesirable problem in that it is easily deformed by the heat of discharge.

A method for manufacturing honeycomb dies aimed at solving the above problems (Japanese Patent Application Laid-open No. 73809/1983)
has already been proposed. The proposed "method for manufacturing a honeycomb die" includes at least three comb-shaped electrodes whose comb-teeth length is equal to the length of one side of a desired regular hexagon, at regular intervals,
The comb teeth are stacked with comb teeth shifted by 172, and the die block is sequentially rotated by 60 degrees relative to the comb tooth shaped electrode body using this comb tooth shaped electrode body.

The forming groove 16 is machined by electrical discharge machining.

(Problems to be Solved by the Invention) As mentioned above, the shape corresponding to the honeycomb body to be formed,
That is, it is very difficult to manufacture an electrode having a shape corresponding to the molding a16 shown in FIG. 9, which poses the undesirable problem of not only increasing the manufacturing cost but also making it difficult to obtain a highly accurate electrode.

In addition, the comb-shaped electrode body used in the above-mentioned "honeycomb die manufacturing method" proposed for the purpose of solving the above-mentioned problems has a plurality of comb-shaped electrodes arranged at predetermined intervals and comb-shaped. are fixed to a predetermined electrode holder in a stacked state so that the electrodes are shifted by 172. Therefore, when assembling the plurality of comb-shaped electrodes, great care must be taken to ensure accurate placement of each of the comb-shaped electrodes, which not only makes the assembly process time-consuming; Since a special electrode holder is required to prevent the comb-shaped electrode from shifting, there is an undesirable problem of increased cost.

Furthermore, if the intersection of the forming grooves in the honeycomb die (for example, the intersection 18 shown in FIG. 9) is formed by a protruding angle formed by plane intersection, cracks may occur at the intersection of the honeycomb body formed by the honeycomb die. Since the honeycomb die is easily damaged due to entering, the intersection of the honeycomb die is formed into an arc shape, for example, to increase the strength of the intersection in the honeycomb body extruded from the honeycomb die. Manufacturing method of catalyst carrier (Special Publication Act 1973
20435)" is known. However, the aforementioned ``Method for manufacturing honeycomb dies'' (Japanese Patent Application Laid-open No. 54-738
The comb-teeth spacing of the comb-teeth-shaped electrode in "09 Publication)" corresponds to the length between the longest vertices of a regular hexagon.

There is an undesirable problem in that the intersection of molding grooves in a honeycomb die machined using an electrode formed by combining a plurality of comb-shaped electrodes becomes a protruding angle state due to plane intersection.

(Means for Solving the Problems) The present invention aims to solve the above-mentioned problems, and therefore, the method for manufacturing an electric discharge machining electrode for honeycomb die forming according to the present invention provides a method for producing a desired regular hexagonal shape. In a method of manufacturing an electric discharge machining electrode for forming a honeycomb die, the plate-shaped protruding electrode portions corresponding to one side of the regular hexagonal forming groove in the honeycomb die having forming grooves are arranged in a staggered manner.

A pre-processing step of cutting grooves in a predetermined portion of an electrode block that has been pre-formed into a desired shape, and a finishing step of giving the thickness of the plate-shaped protruding electrode portion. It is characterized by

This will be explained below with reference to one drawing.

(Example) Figure 1 is a perspective view of an electrode manufactured according to the present invention, Figure 2 is a perspective view of an electrode manufactured according to the present invention.
Figures (A) to E) are explanatory diagrams for explaining one embodiment of the present invention, Figure 3 is a plan view of an electrode manufactured based on the embodiment illustrated in Figure 2, and Figures 4 to 6. The figure is a partial plan view of a forming groove machined by electric discharge machining using an electrode manufactured according to the present invention (the electrode shown in FIG. 3 or the electrode shown in FIG. 8, which will be described later); FIGS. 7(A) to C) is an explanatory diagram for explaining another embodiment of the present invention, FIG. 8(A)
and (B) show a plan view of an electrode manufactured based on the embodiment shown in FIG.

The electrode 1 shown in FIG. 1 is a monolithic electric discharge machining electrode manufactured based on the manufacturing method of the present invention, which will be described later. That is, the above electrode 1 is.

The electrode base part 2 and the protruding electrode part 3 are integrally constructed,
By rotating the electrode 1 relative to the die block by 60 degrees and performing electric discharge machining, forming grooves for forming a regular hexagonal honeycomb are formed. Two manufacturing methods of the present invention will be explained below.

FIG. 2 is a detailed explanatory diagram of the present invention, and FIG.
(B) and (C) show a pre-processing process, FIG. 2(D) shows a finishing process, and FIG. 2(E) shows a supplementary explanatory diagram regarding FIGS. 2(A) to D). And code 1 in figure 1
′ is the electrode block.

4 is a first pre-processed groove, 5 and 5' are second pre-processed grooves,
6 represents a finishing groove. For convenience of explanation, dotted lines in Figure 9 indicate forming grooves in the honeycomb die to be formed.

First, as shown in FIG. 2(A), a block 1' made of, for example, graphite material is formed into a block shape.
, parallel grooves having a predetermined pitch P1, that is, the first pre-processing a4, 4 . Perform groove cutting. The groove width d of the first pre-processed groove 4 and the pitch P1 are predetermined based on the shape and dimensions of the honeycomb body (indicated by dotted lines) (described later in relation to FIG. 2(E)). ). Further, the depth corresponds to the height H of the protruding electrode portion 3 shown in FIG.

Next, as shown in FIG. 2(B), the first pre-processed grooves 4, 4. ... and at a predetermined pitch P2. Groove width d
2nd pre-processing 45, 5 degrees... having 2 is cut in a staggered manner. Note that the pitch P2 and the groove width dz are predetermined based on the shape and dimensions of the honeycomb body (dotted lines in the figure) (described later in relation to FIG. 2(E)),
The depth corresponds to the arrow shown in FIG. 1, similarly to the first pre-processed groove 4.

In addition, in relation to FIG. 2(B), the second pre-processed groove 5.5.
. . . as mentioned above, but the second illustration in Fig. 2 (B) above
Pre-machined groove 5.5. ···Instead of.

Pre-machined hole 5' as shown in FIG. 2(C).

5', . . . may be bored at the pitches P1 and P2 described above. Pre-cough processing holes 5', 5'
.

The diameter of ... is given by the 9th order equation.

JT177〒777-101≦D<5L-The processing steps shown in FIG. J
l$5.5. ...or pre-machined holes 5', 5',...
After machining, the first pre-machined grooves 4, 4.
It is also possible to perform groove cutting.

After the above pre-processing step is completed, the finishing step shown in FIG. 2(D) is performed. That is, the first pre-processing mentioned above? J4.4
．． Finishing processing that is perpendicular to ... and has a predetermined pitch P3° groove width d? ! 6.6. Perform groove cutting. In addition,
The pitch P3 has the same dimensions as the pitch P2 shown in FIG. 2 (B), but at one position it is 1/2 Pg.
(=1/2 P3). Further, the groove width d3 is predetermined based on the shape and dimensions of the honeycomb body (dotted line in the figure) (described later in relation to FIG. 2(E)), and the depth is as shown in FIG. Corresponds to the arrow.

By carrying out the pre-processing process and the finishing process explained in relation to FIGS.
The electrode 1 illustrated in the figure is manufactured. A plan view of the electrode 1 is shown in FIG. In FIG. 3, the pitch Px in the X direction, the pitch Py in the y direction, the plate thickness t, and the length β of the protruding electrode portion 3 are
P or P3 shown in Figures (A) or D)
and d, to d3. That is, now,
The desired cross-sectional shape of the honeycomb body is a regular hexagon as shown in FIG. 2(E).

When the thickness of the plate is t, and the length of the negative side of the center line of the plate thickness (dotted chain line in the figure) is L, the above-mentioned Pl to P3°d to d3 may be set as follows. Below, Figure 2 (E)
This will be explained in relation to.

The pitch P1 of the first pre-processed groove (solid line in the figure) 4 is rL (
1+5in30')j, groove width d, is at least r
L sin 30°" or less.

The pitch P2 of the second pre-processed groove (double-dashed line in the figure) 5 is rL
cos30'J, and the groove width d2 is small (both are greater than or equal to rtJ).

The pitch P3 of the finishing groove (three-dot chain line in the figure) 6 is rL c
os30 ”J, groove width d, r (L cos30
'-t)'.

By performing electrical discharge machining by sequentially rotating the electrical discharge machining surface of the die block by 60 degrees relative to the electrode 1 manufactured by the manufacturing method explained above, a honeycomb die as shown in FIG. 4 is formed. A groove 7 is formed. That is, the forming groove 7 shown in FIG. 4 has the pitch P of the pre-processing grooves 4, 5 and the finishing groove 6 in the above-mentioned pre-processing process and finishing process.

The electrodes 1 were formed using the electrodes 1 manufactured under the above-mentioned setting conditions for Pl to Pl and groove widths d to d3. However, since the intersection portion 10 of the forming groove 7 shown in FIG. 4 is constituted by a protruding angle formed by plane intersection, this is not preferable for the reason explained at the beginning of this specification in connection with FIG. 9. That is, as shown in FIG.
A shape in which so-called chamfering is performed in a straight line, or a sixth shape
It is desirable to have a chamfered shape in a five-arc shape as shown in the figure. In order to form the forming groove 8 as shown in FIG. 5 above, the electrode 1 shown in FIG. good. In this way, when performing electrical discharge machining by moving the electrode 1, the groove width d of the first pre-machined groove 4 described above with reference to FIG. There is no need to do the following.

Next, another embodiment of the present invention will be described with reference to FIG. The embodiment shown in FIG. 7 is basically the same as the embodiment shown in FIG. 2 described above, but the forming groove 7 shown in FIG. This is a method of manufacturing an electrode in which the forming groove 7 shown in FIG. 4 can be formed.

In the embodiment shown in FIG. 7, the seventh
As shown in FIG. 7(A) or FIG. 7(B), the third pre-processed groove 11 or 11' is cut. The third pre-processed groove 11 or 11' is.

This corresponds to the second pre-processed groove 5 in the embodiment shown in FIG. 2, and the pitch P4 and groove width d4 are the same as the pitch P2 and groove width d2 of the pre-processed groove 5. Further, the longitudinal dimension of the third pre-processed groove 11 shown in FIG. 7(A) is smaller than at least the length between the opposing vertices of the regular hexagon shown by the dotted line. In addition, in FIG. 7(A).

Although the third pre-processed groove 11 is illustrated as a rectangle,
The corner portion may be formed in an arc shape.

FIG. 7(B) The third pre-processing a11′ shown in FIG.
The protruding electrode portion 1 shown in FIG. 8(B) which will be described later is
This is for forming the end face in the longitudinal direction of 3' into a predetermined arcuate curved surface.

After the pre-processing steps described in connection with FIGS. 7(A) and 7(B) are completed, the finishing step shown in FIG. 7(C) is performed. The finishing process is carried out in exactly the same manner as in the embodiment shown in FIG. 2 described above. That is, the protruding electrode portion 13 is formed by removing the hatched portion shown in the figure in the finishing process.

Electrodes 14 and 14' made according to the embodiment shown in FIG. 7 are illustrated in FIGS. 8A and 8B.

The electrode 14 shown in FIG. 8(A) is manufactured through the pre-processing process explained in relation to FIG.
The electrode 14' shown in FIG. 7(B) was manufactured through the pre-processing process described in connection with FIG. 7(B).

Electrode 14 manufactured based on the embodiment shown in FIG. 7 above
Alternatively, the forming groove 8 of the honeycomb die shown in FIG. 5 or FIG. 9 is formed. In addition, in FIG. 7(A).

If the relationship L>3.9t is satisfied, Fig. 7(A)
Instead, a pre-processing step as shown in FIGS. 2(A) to 2(C) may be performed.

(Effects of the Invention) As explained above, according to the present invention, in a honeycomb die in which a desired regular hexagonal molding groove is formed in a mesh shape, a plate-shaped projection corresponding to one side of the regular hexagonal molding groove is formed. It is now possible to simply and easily manufacture an electrode for electric discharge machining with an integral structure in which the electrode parts are arranged in a staggered manner, and by performing electric discharge machining using the electric discharge machining electrode, the forming groove of the honeycomb die can be easily manufactured. can be processed with high precision.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of an electrode manufactured according to the present invention;
Figures (A) to E) are detailed explanatory diagrams of the present invention, Figure 3 is a plan view of an electrode manufactured based on the embodiment shown in Figure 2, and Figures 4 to 6 are respectively diagrams for explaining the present invention. FIG. 3 is a partial plan view of a forming groove machined by electric discharge machining using an electrode manufactured based on the above. 7(A) to 7(C) are explanatory views of another embodiment of the present invention, and FIGS. 8(A) and 8(B) are plan views of electrodes manufactured based on the embodiment shown in FIG. 7. 9(A) to 9(C) are explanatory diagrams of a general example of a honeycomb die, and FIGS. 10(A) and 10(B) show a conventional example of an electrode. In the figure, 1.14 and 14' are electrodes, 2 is the electrode base, and 3
．． 13 and 13' are projecting electrode parts, 4 is a first pre-processed groove, 5 and 5' are second pre-processed grooves, 6 is a finishing groove, grooves 9 to 9 are forming grooves, and 10 is an intersection portion. 11 and 11' represent third pre-machined grooves, and 12 represents a groove cutting tool. Patent applicant: Nippon Insulator Co., Ltd. (1 other person) Agent: Patent attorney Mori 1) Hiroshi (2 others)) 2. (B) (C) ¥53 Kokuyu 50 6th product No. 7m (C) Higashi 8th (A) (B) Ougi 9 countries

Claims (1)

[Claims] A method for producing an electric discharge machining electrode for forming a honeycomb die, in which plate-shaped protruding electrode portions corresponding to one side of the regular hexagonal forming groove are arranged in a staggered manner in a honeycomb die having a desired regular hexagonal forming groove. The method includes a pre-processing step of cutting grooves in predetermined portions on an electrode block that has been previously formed into a desired shape, and a finishing step of giving the plate-like protruding electrode portion a thickness. A method of manufacturing an electrical discharge machining electrode for honeycomb die forming, characterized by: