JPH0474131B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention is a method for manufacturing a honeycomb die, particularly a method for manufacturing a honeycomb die for forming a honeycomb body having a desired regular hexagonal shape. Using an electrical discharge machining electrode that has a plate-shaped protruding electrode part corresponding to one side of the regular hexagon of the shaping groove of the honeycomb die, the electrical discharge machining electrode is moved 60 degrees relative to the die block that is the object of machining. By rotating the electrical discharge machining electrode in each of the angular directions and moving the electrical discharge machining electrode a predetermined distance in each of the angular directions, the intersection of the forming grooves is chamfered. The present invention relates to a method for manufacturing a honeycomb die in which forming grooves having a shape are formed.

(Prior Art) A honeycomb die as shown in FIG. 5 has been known as an extrusion die for forming a honeycomb body having a regular hexagonal cross-section. 5A is a front view of the entire surface, FIG. 5B is a rear view, and FIG. 5C is a sectional view taken along arrow A-A in the figure. Number 10 in the diagram
is a honeycomb die, and is provided with a forming groove 11 bored in a shape corresponding to the cross-sectional shape of the honeycomb body to be formed, and a plurality of introduction holes 7 communicating with the forming groove 11. Note that the reference numeral 12 represents an intersection.

The forming grooves 11 of the honeycomb die 10 are generally formed by electrical discharge machining. That is, for example, a graphite electrical discharge machining electrode (hereinafter referred to as an electrode) having a shape corresponding to the honeycomb body to be formed, or metal electrodes 13 to 17 as shown in FIG. 6A or B are used. This is done by electrical discharge machining. However, in general, the mesh shape (regular hexagon in the present invention) constituting the honeycomb body
For example, the length of one side is about 2 mm, and the wall thickness is about 0.2 mm.
Because of the fineness of the electrodes, there was a problem in that it was difficult to manufacture electrodes with high precision. Further, the electrodes 13 to 16 shown in FIG. 6 are usually manufactured by pressing a steel plate, for example, but this is not preferable because the bent portions become rounded.

A method for manufacturing honeycomb dies (Japanese Unexamined Patent Publication No. 73809/1983) has already been proposed to solve the above-mentioned problems. The proposed "method for manufacturing honeycomb dies" consists of at least three comb-shaped electrodes whose comb teeth are equal to the length of one side of a desired regular hexagon, and which are arranged at regular intervals, and each 1/2 of the comb teeth. The comb-shaped electrode body is stacked in a staggered manner, and a die is applied to the comb-shaped electrode body.
Rotate the blocks sequentially by 60 degrees,
The forming groove 11 is machined by electrical discharge machining.

(Problems to be Solved by the Invention) The comb-shaped electrode body used in the above-mentioned proposed "method for manufacturing a honeycomb die" has a plurality of comb-shaped electrodes arranged at predetermined intervals and one comb-shaped electrode. /2
The electrodes are stacked in a staggered manner and fixed to a predetermined electrode holder. Therefore, when assembling the plurality of comb-shaped electrodes in a stacked state, great care must be taken to accurately arrange each of the comb-shaped electrodes, which makes the assembly process time-consuming. Moreover, since a special electrode holder is required to prevent the assembled comb-shaped electrode from shifting, there is an undesirable problem of increased cost. In addition, a honeycomb die 10 manufactured by electric discharge machining using the above-mentioned comb-shaped electrode
Intersection 12 of molding grooves 11 (as shown in Figure 5)
becomes a protrusion angle state due to plane intersection. Therefore, there was a problem in that the ceramic honeycomb body manufactured by the honeycomb die 10 was easily damaged such as cracks at the intersections (portions corresponding to the intersections 12).

In order to prevent the damage described above, there is known a method for producing a catalyst carrier (Japanese Patent Publication No. 51-20435) in which arcuate or linear enlarged portions are formed at the intersections of the honeycomb body. However, according to the publication, the extrusion die, that is, the honeycomb die used for manufacturing the honeycomb body, has the intersection portions 12 of the conventionally used honeycomb die (shown in FIG. 5) in an arc shape or a straight shape, for example. It was removed by electrical discharge machining. Therefore, there is a problem with the method for manufacturing honeycomb dies used to carry out the "method for manufacturing catalyst carrier" of the above-mentioned publication.
That is, first, a honeycomb die 1 as shown in FIG.
0 is formed and then electrical discharge machining of the intersection portion 12 is performed, which not only complicates the manufacturing process, but also requires electrodes for performing electrical discharge machining of the intersection portion 12. Honeycomb
An undesirable problem is that the manufacturing cost of the die increases.

(Means for solving the problems) The present invention aims to solve the above problems, and therefore, the honeycomb of the present invention
The die manufacturing method is a honeycomb die manufacturing method for molding a desired regular hexagonal honeycomb body, in which a plate-shaped protruding electrode portion corresponding to one side of the regular hexagon of the forming groove of the honeycomb die is formed. Using the disposed electric discharge machining electrode, perform electric discharge machining by rotating the electric discharge machining electrode 60 degrees relative to the die/block to be machined.
In electrical discharge machining in each of the angular directions, the electrical discharge machining electrode is moved a predetermined distance in each of the angular directions to form a forming groove in which the intersection of the forming grooves has a so-called chamfered shape. It is characterized by This will be explained below with reference to the drawings.

Embodiment FIG. 1 is an explanatory diagram of an embodiment of an electrode used in the present invention, FIG. 2 is an explanatory diagram of an embodiment of the manufacturing method of the present invention, and FIG. 3 is an explanatory diagram of an embodiment of an electrode used in the present invention. FIG. 4, a partial plan view of the honeycomb die shown in FIG. 4, shows the electrodes used in another embodiment of the invention.

Prior to explaining the manufacturing method of the present invention, the electrode used in the present invention will be explained with reference to FIG. In addition, FIG. 1A shows a perspective view of the electrode, and FIG.
represents a protruding electrode portion. Note that the dotted line in FIG. 1B indicates the shape of the forming groove formed in the honeycomb die for convenience of explanation.

The electrode 1 shown in FIG. 1 is an electrode for electrical discharge machining having an integral structure, which is manufactured based on the "Method for manufacturing electrical discharge machining electrode for honeycomb die forming" which was filed at the same time as the present application. That is, the electrode 1 is made of graphite, for example, and includes an electrode base 2 and a protruding electrode part 3.
are integrally constructed. Note that the plate thickness t, length l, height H, pitch Px in the x direction, pitch Py in the y direction, etc. of the protruding electrode portion 3 are the dimensions of the forming groove of the honeycomb die (dotted line in the figure).
It is predetermined in accordance with. That is, the shape of the forming groove in the honeycomb die is a regular hexagon, and when the groove width of the forming groove is t and the length of one side of the regular hexagon passing through the center of the groove width is L, the first
In the illustrated embodiment, the plate thickness t is "t", the length l is smaller than at least "L+√3t", the pitch Px is "Lcos30°", and the pitch Py is "L(1+
sin30°)". It goes without saying that the height H is set larger than the depth of the forming groove.

In one embodiment of the manufacturing method of the present invention, the forming groove is processed by electrical discharge machining using the electrode 1 described above. The steps will be explained below in order.

() Dice/block forming process First, through processes such as material cutting, forging, heat refining, cutting, and polishing, a die/block with the desired shape and dimensions is manufactured.

() Introductory hole forming step Next, an introductory hole 7 as shown in FIG. 5, for example, having a predetermined depth from the rear surface of the die block is bored.

() Molding Groove Forming Step Molding grooves are formed by electrical discharge machining using the electrode 1 described above (shown in Figure 1). This will be explained below with reference to FIG. Note that numerals 1 and 3 in the figure correspond to those in FIG. 1, 4 represents the die block, and 5 represents the first portion of the forming groove.

(-1) First molding groove forming step First, the electrode 1 and the die block 4 are aligned. This alignment means aligning the center point 0 of the electrode with the center point 0 of the die block 4, and then aligning the electrode 1 or the die block 4 with the center point 0 of the electrode.
The block 4 is rotated about the center point 0 (hereinafter referred to as relative rotation), and the protruding electrode part 3 is placed in the molding groove to be formed (indicated by the dotted line in the figure) as shown in FIG. It is meant to match. This situation is illustrated in FIG. Note that the center of the introduction hole (not shown) coincides with the intersection of the center lines of the width of the forming groove to be formed.

After performing the above alignment, a part of the forming groove (corresponding to the protruding electrode part 3 shown in FIG. 2) of a predetermined depth communicating with the introduction hole 7 is bored by performing well-known electrical discharge machining. do. Thereafter, the first forming groove portion 5 is formed by moving the electrode 1 and the die block 4 relatively by a predetermined distance in the direction of the arrow shown in the figure and in the opposite direction and performing electrical discharge machining.

(-2) Second forming groove forming step Next, the positional relationship between the electrode 1 and the die block 4 was restored to the state at the start of the first forming groove forming step, that is, the state shown in FIG. Above,
A relative rotation of 60 degrees is performed around the center point O. After the relative rotation, the relative positional relationship between the electrode 1 and the die block 4 is such that the direction of the protruding electrode portion 3 coincides with the direction of the arrow ( ) shown in the figure. Thereafter, electrical discharge machining similar to the first molding groove forming step described above is performed.

(-3) Third molding groove forming step Furthermore, after restoring the positional relationship between the electrode 1 and the die block 4 to the state at the start of processing in the second molding groove forming step, the center point O is set as an axis. perform a relative rotation of 60 degrees. After the relative rotation, the relative positional relationship between the electrode 1 and the die block 4 is such that the direction of the protruding electrode portion 3 coincides with the direction of the arrow ( ) shown in the figure. Thereafter, electrical discharge machining similar to the first and second forming groove forming steps described above is performed.

By carrying out the first to third forming groove forming steps described above, as shown in FIG.
A honeycomb die 4' having a forming groove 6 having a diameter of 100 mm is completed.

Next, another embodiment of the present invention using the electrode 1' shown in FIG. 4 will be described.
The electrode 1' used in this embodiment is manufactured basically in the same manner as the electrode 1 shown in FIG. 1 described above. That is, the electrode 1' is made of graphite, for example, and has an electrode base 2' and a protruding electrode part 3' integrally constructed. The protruding electrode portion 3' is, as shown in FIG. 4B,
The pitches in the x and y directions are twice the pitches Px and Py of the protruding electrode portions 3 in the electrode 1 shown in FIG. 1 described above. Further, the plate thickness t, length l, and height H are the same as in the case of the electrode 1 shown in FIG.

The manufacturing method using the electrode 1' is basically the same as the manufacturing method described above with reference to FIG. That is, by performing the above-mentioned molding groove forming step () using the electrode 1', half of the molding groove to be formed is processed, and then the relative position of the electrode 1' and the die block 4 is determined. is shifted by Px in the x direction and Py in the y direction, and the above-mentioned forming groove forming step () is repeated again to complete the desired honeycomb die 4' (shown in FIG. 3).

(Effects of the Invention) As explained above, according to the present invention, the intersections of regular hexagonal honeycomb forming grooves are chamfered by electrical discharge machining using a highly accurate electrical discharge machining electrode that can be simply and easily produced. Since it is possible to form molding grooves with a different shape in the same process, it is possible to shorten the manufacturing process, and the honeycomb is used to manufacture regular hexagonal honeycomb bodies at low cost and with high precision.・You can provide dice.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of one embodiment of the electrode used in the present invention, FIG. 2 is an explanatory diagram of one embodiment of the manufacturing method of the present invention, and FIG. 3 is a honeycomb manufactured based on the embodiment illustrated in FIG.・A partial plan view of the die; FIG. 4 is an explanatory diagram of an electrode used in another embodiment of the present invention; FIG. 5 is an explanatory diagram of a general example of a honeycomb die;
FIG. 6 shows a conventional example of an electrode. In the figure, 1 and 1' are electrodes, 2 and 2' are electrode bases, 3 and 3' are protruding electrode parts, and 4 is a die.
In the block, 4' is a honeycomb die, 5 is the first part of the forming groove, 6 is the forming groove, 7 is the introduction hole, and 8 is the intersection.

Claims (1)

[Claims] 1. A honeycomb structure equipped with a plurality of introduction holes and a regular hexagonal honeycomb-shaped molded groove communicating with the introduction holes.
The die manufacturing method includes an introduction hole forming step in which the above-mentioned introduction hole is bored in the die block to be processed, and a plate-shaped protruding electrode portion corresponding to one side of the desired regular hexagonal forming groove is arranged. a forming groove forming step of forming the forming groove by electric discharge machining using an electric discharge machining electrode made of After setting, the above-mentioned forming should be formed by electric discharge machining, in which the above-mentioned electrical discharge machining electrode is fed a predetermined vertical distance to the above-mentioned die block, and the protruding electrode portion is horizontally moved a predetermined distance in the plate direction. A first molding groove forming step for forming two sides of each regular hexagon of the groove; After the first molding groove forming step, the die block and the electrical discharge machining electrode are rotated 60 degrees relative to each other; and a second molding groove forming step of forming the other two sides of each regular hexagon of the molding groove by performing electric discharge machining similar to the first molding groove forming step, and the second molding. After the groove forming process is completed, the die block and the electric discharge machining electrode are further rotated 60 degrees relative to each other, and electric discharge machining is performed in the same manner as in the first and second molding groove forming processes. A method for manufacturing a honeycomb die, comprising a third forming groove forming step of forming the other two sides of each regular hexagon of the forming groove.