JP3402206B2 - Method for manufacturing mold for forming honeycomb structure - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a method for manufacturing a honeycomb structure forming die having lattice-shaped slit grooves.

[0002]

2. Description of the Related Art For example, a ceramic honeycomb structure containing cordierite as a main component is manufactured by extruding a material using a molding die. This honeycomb structure has a large number of cells formed by providing partition walls in a grid pattern, and various cell shapes such as a square and a hexagon are available.

For example, in order to manufacture a honeycomb structure having hexagonal cells, a die having hexagonal lattice-shaped slit grooves is used. Specifically, supply holes 81 for supplying materials
And a die 8 having a slit groove 82 communicating with the supply hole 81 and provided in a hexagonal lattice shape (see FIG. 1).

In manufacturing the mold 8, the hole forming surface 84 on which the supply hole 81 is provided and the slit groove 82 are formed.
A metal mold material 80 having a groove forming surface 85 for forming a groove is prepared (see FIG. 2). Then, a supply hole 81 is provided on the hole forming surface with a drill or the like, and a hexagonal grid-like slit groove 82 is provided on the groove forming surface by electric discharge machining, so that the slit groove 82 and the supply hole 81 communicate with each other. Obtain the mold 8.

As shown in FIG. 10, the electric discharge machining is performed by using the electric discharge machining electrode 9 provided with a lattice-shaped machining surface 90 corresponding to the entire surface of the slit groove 82 to be obtained, and the die material 80. This is performed by repeating the discharge through the machining liquid between the groove forming surface 85 and the groove forming surface 85. The machining fluid is supplied from the machining fluid supply pipe 97 of the machining fluid supply jig 98 arranged on the back side of the electric discharge machining electrode 9.

[0006]

However, the above-mentioned conventional method for manufacturing a honeycomb structure forming die has the following problems. That is, conventionally, the processing of the slit groove 92 is
The electric discharge machining is performed by using the electric discharge machining electrode having a lattice shape corresponding to the shape of the entire slit groove to be obtained. During this electric discharge machining, the electric discharge machining electrode may be distorted or deformed due to variations in wear. In this case, there is a quality problem in that the depth of the slit groove obtained varies.

On the other hand, since the electric discharge machining electrode is made of a material having a very high hardness such as a tungsten alloy, the manufacturing period of the electrode is long, for example, several tens of days. Therefore, for example, when a new die for forming a honeycomb structure is to be manufactured, it first takes several tens of days to manufacture an electrode for electric discharge machining, and then machining of a slit groove requires several tens of days. The lead time was extremely long.

The present invention has been made in view of the above conventional problems, and provides a method for manufacturing a honeycomb structure forming die capable of processing a slit groove with high accuracy and a short lead time. It is the one we are trying to provide.

[0009]

According to a first aspect of the present invention, there are provided a plurality of supply holes for supplying a material, and slit grooves communicating with the supply holes and provided in a lattice shape for forming the material into a honeycomb shape. In the method of manufacturing a die for forming a honeycomb structure having the above, the slit groove is processed by a small-sized electric discharge machining having a groove forming surface of a die material and a processing surface having an area smaller than the area of the groove forming surface. There rows by multiple discharge machining using an electrode, the working surface of the electrical discharge machining electrode includes an upper
When the groove forming surface is divided into n areas in the width direction,
The area is set to a size that can be machined and
Using the electric discharge machining electrode to cover the n regions
Repeated multiple times for each unit of processing to the specified depth.
It is carried out by returning and the above unit machining is performed in the above n
The central area located in the approximate center of these areas is released first.
Electro-mechanical processing, and then apply in order from the side near the central area.
A method for manufacturing a honeycomb structure molding die, which is characterized in that

What is most noticeable in the present invention is that the slit groove is subjected to electric discharge machining a plurality of times by using an electric discharge machining electrode having a machining surface having an area smaller than the area of the groove forming surface of the die material. It is to be done by.

The electric discharge machining electrode has a machining surface having a smaller area than the groove forming surface as described above, and is smaller than the conventional electric discharge machining electrode. In addition, the above-mentioned multiple times of electric discharge machining may be repeated by using one of the above-mentioned miniaturized electric discharge machining electrodes, or it may be replaced with another small electric discharge machining electrode each time or every plural times. You may go.

Next, the function and effect of the present invention will be described.
In the method for manufacturing a die for molding a honeycomb structure of the present invention, the machining surface of the electrode for electric discharge machining is made smaller than the groove forming surface of the die material, and is made smaller than before. Therefore, the electric discharge machining electrode can be less deformed by distortion than the conventional large size covering the entire surface where the groove is formed, and can also reduce the variation in the electric discharge state depending on the location during electric discharge machining. it can. Therefore, the deformation and the variation in wear are smaller than in the conventional case, and the formation depth of the slit groove can be accurately controlled.

Further, as described above, by making the area of the machining surface smaller than before, it is possible to supply and discharge the machining liquid used during electric discharge machining more smoothly and sufficiently than before. Therefore, the sludge generated by the electric discharge machining and hindering the subsequent electric discharge machining can be removed more efficiently than before. Therefore, the electric discharge phenomenon that occurs between the electrode and the die material is performed more actively than before, which improves the processing speed.

Further, as described above, since the electric discharge machining electrode is small, the manufacturing period thereof can be shortened as compared with the conventional case. Therefore, the machining of the slit groove, which can be started only after the electrode for electric discharge machining is manufactured, can be started earlier than in the past. Therefore, the lead time in manufacturing the die for forming the honeycomb structure can be significantly shortened as compared with the conventional case (see the embodiment example).

As described above, according to the present invention, it is possible to provide a method for manufacturing a honeycomb structure molding die, which can process the slit groove with high accuracy and in a short lead time.

Next , the machining surface of the electric discharge machining electrode is provided with a size capable of machining one area when the groove forming surface is divided into n areas in the width direction, and The electric discharge machining is performed by repeating a plurality of times of unit machining, in which one or a plurality of the electric discharge machining electrodes are used to machine each of the n regions to a predetermined depth .

That is, instead of grooving each of the above regions to a desired depth by one electric discharge machining, first,
It is preferable that the entire groove forming surface is processed to a predetermined depth by the unit processing, and then the unit processing is repeated to increase the groove depth. As described above, by performing the electric discharge machining stepwise not only in the width direction but also in the depth direction in multiple steps, it is possible to suppress the local machining variation and further improve the machining accuracy of the slit groove. Can be made.

Further , in the unit machining, the central region located substantially in the center of the n regions is first subjected to electric discharge machining,
Then, processing is performed in order from the side closer to the central region . This
As a result , changes in slit groove width due to subtle machining variations can be made substantially symmetrical. Therefore, the moldability at the time of molding a honeycomb structure using the obtained honeycomb structure molding die can be improved.

Further, the invention of claim 2 is a compound for supplying materials.
Number of supply holes and a material that is provided in a grid pattern and communicates with the supply holes
With slit grooves for forming the material into a honeycomb shape
In a method of manufacturing a die for forming a honeycomb structure,
The processing of the above-mentioned slit groove is performed by cutting the groove forming surface of the die material
Small size with a processing surface smaller than the area of the forming surface
By performing electric discharge machining multiple times using the electric discharge machining electrode
It performed, and the processing surface of the electrical discharge machining electrode, all parts that contribute to processing has a lattice shape corresponding to the lattice shape of the slit groove, have the incomplete sides which do not form a lattice Honeycomb structure characterized by not performing
It is in a method of manufacturing a molding die. In this case, it is possible to improve the machining accuracy of the boundary portion between the adjacent electric discharge machining portions.

Further, the invention of claim 3 is a compound for supplying materials.
Number of supply holes and a material that is provided in a grid pattern and communicates with the supply holes
With slit grooves for forming the material into a honeycomb shape
In a method of manufacturing a die for forming a honeycomb structure,
The processing of the above-mentioned slit groove is performed by cutting the groove forming surface of the die material
Small size with a processing surface smaller than the area of the forming surface
By performing electric discharge machining multiple times using the electric discharge machining electrode
Performed, and electric discharge machining the second and subsequent one of the plurality of times of electric discharge machining moves the electrical discharge machining electrode so that at least one overlap of the grating of the previous discharge machining the machined surface to the formed gratings by Ha
It is in a method for manufacturing a mold for molding a Nicham structure. In this case, it is possible to prevent displacement of the obtained slit groove lattice.

Further, as in the invention described in claim 4 , a machining fluid supply jig for supplying a machining fluid for electric discharge machining is disposed on the electric discharge machining electrode, and the machining fluid supply jig is provided. It is preferable that the jig for machining is provided with two or more processing liquid ejection ports. In this case, it is possible to make the supply of the working liquid to the working surface uniform and improve the sludge removal effect, and thereby to make the discharge uniform. Therefore, the processing accuracy of the slit groove can be further improved.

[0022]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiment 1 A method for manufacturing a honeycomb structure forming die according to an embodiment of the present invention will be described with reference to FIGS. In this example, as shown in FIG. 1, a plurality of supply holes 81 for supplying materials are provided.
And a slit 8 for communicating with the supply holes 81 and having a lattice shape for forming the material into a honeycomb shape. The processing of the slit groove 81 is as shown in FIGS.
The groove forming surface 85 of the die material 80 is subjected to electric discharge machining a plurality of times by using the small-sized electric discharge machining electrode 1 having the machining surface 10 having an area smaller than the area of the groove forming surface 85.

This will be described in detail below. As shown in FIG. 1, the honeycomb structure molding die 8 manufactured in this example has hexagonal lattice-shaped slit grooves 81. In manufacturing the honeycomb structure forming die 8, first, as shown in FIG. 2A, a die material 80 having a groove forming surface 85 and a hole forming surface 84 on the front and back sides is prepared.

Next, as shown in FIG. 2B, a large number of supply holes 81 are formed in the hole forming surface 84 of the die material 80 by drilling. After that, as shown in FIGS. 2C and 6, hexagonal lattice-shaped slit grooves 82 are formed by electric discharge machining.

In the electric discharge machining, as shown in FIGS. 3 and 4, a small electric discharge machining electrode 1 is used. In the electric discharge machining electrode 1 of this example, the length L of the machining surface 10 is the mold material 80.
The width W of the groove forming surface 85 is larger than the width R of the groove forming surface 85, but the width W of the processed surface 10 is smaller than the width R of the groove forming surface 85.

More specifically, the processed surface 1 will be described.
At 0, the hexagonal lattices 15 for 15 columns are provided in the width direction to have the width dimension W. This width W is determined by the groove forming surface 8
The width R is about 1/9. In addition, the machining surface 10 of the electric discharge machining electrode 1 has a hexagonal lattice shape in all the portions that contribute to machining, and does not have an imperfect side portion that does not form a lattice. Specifically, as shown in FIG. 4A, all the end portions of the processed surface 10 are hexagonal grid electrodes, and the hexagonal shape shown in FIG. It does not have the complete side 109. Further, the hexagonal lattice of the machined surface 10 of the electric discharge machining electrode 1 is provided so as to penetrate to the back surface 19.

Further, as shown in FIG. 5, a machining liquid supply jig 5 is provided on the back surface 19 of the electric discharge machining electrode 1. The processing liquid supply jig 5 is provided with a 7 for supplying the processing liquid.
The book supply pipe 55 is connected, and it corresponds to each supply pipe 7
Machining fluid jets (not shown) at certain locations are provided on the electrode contact surface. On the upstream side of the seven supply pipes 55, each supply pipe 55
A branching jig 56 for adjusting the distribution and the flow rate of the machining liquid to the workpiece is connected. The branching jig 56 is connected with a feed pipe 58 for feeding the working liquid further upstream, and is provided with seven knobs 57 for adjusting the flow rate of each supply pipe 55.

Further, the electric discharge machining electrode 1 provided with the machining liquid supply jig 5 is set in the electric discharge machining apparatus 6 as shown in FIG. The electric discharge machine 6 has a table 61 for setting a die material 80 and a head 62 for holding the electric discharge machining electrode 1. Head 62
As shown in FIG. 5, the electric discharge machining electrode 1 and the machining liquid supply jig 5 are fixed to the tip thereof and are movable up and down and left and right.

Next, a procedure for forming slit grooves on the groove forming surface 85 of the die material 80 will be described with reference to FIG. First, as shown in the figure, the groove forming surface 85 is divided into nine regions S1 to S9 in the width direction. These areas S1 to
The width of S9 is set to be slightly smaller than the width W of the processed surface 10 of the electric discharge machining electrode 1.

Electric discharge machining is performed on each of the nine regions S1 to S9 using the electric discharge machining electrode 1 described above. In this example, after electric discharge machining is performed to a desired slit groove depth in one area, the electric discharge machining electrode 1 is moved to an adjacent area to perform electric discharge machining to a desired slit groove depth D (FIG. 1A) again. I do. Then, the machining of the slit groove 82 is completed by repeating this electric discharge machining 9 times.

Further, the electric discharge machining electrode 1 is moved so that at least one row of the lattice of the machining surface 10 overlaps the lattice formed by the previous electric discharge machining.
Specifically, as shown in FIG. 8, when a new slit groove lattice B (FIG. 8B) is formed next to the slit groove lattice A (FIG. 8A) that was previously subjected to electric discharge machining. Has
The electric discharge machining electrode 1 was moved so that the grids C for one row of both overlap each other.

The electric discharge machining electrode 1 is replaced with a new one according to the state of wear. For example, when the electric discharge machining electrodes 1 are replaced every two electric discharge machining, a total of four electric discharge machining electrodes 1 are used.

Next, the function and effect of this example will be described. In the method for manufacturing the honeycomb structure molding die of this example,
The machining surface 10 of the electric discharge machining electrode 1 is made much narrower and smaller than the conventional one. Therefore, the electric discharge machining electrode 1 is
Deformation due to distortion can be made smaller than before,
In addition, it is possible to reduce the variation in the electric discharge state depending on the location during electric discharge machining. Therefore, the deformation and wear variation of the electric discharge machining electrode 1 are smaller than in the conventional case.

In particular, in this example, the machining fluid ejection port is
Since the location is also provided, a sufficient amount of the working fluid can be supplied to the working portion in a uniform state. Therefore, by improving the sludge removing effect, the electric discharge state during electric discharge machining can be made more uniform. Therefore, the uneven wear of the electrodes can be further suppressed, and the formation depth of the slit groove can be accurately controlled.

Further, in this example, the electric discharge machining electrode 1 is used.
The processed surface 10 has no incomplete side portion. Then, in the second and subsequent electric discharge machining among the plurality of electric discharge machining, the electric discharge machining electrode 1 is moved so that one grid line of the machining surface overlaps with the grid formed by the previous electric discharge machining. Do it. Therefore, it is possible to prevent the positional deviation of the grid of the obtained slit grooves, and it is possible to improve the machining accuracy of the boundary portion of the electric discharge machining that is repeatedly performed.

Further, as described above, it is possible to reduce the electric discharge variation depending on the place during electric discharge machining as compared with the conventional case.
Further, as described above, by making the area of the machining surface 10 smaller than before, it is possible to supply and discharge the machining liquid used during electric discharge machining more smoothly and sufficiently than before. Therefore, the sludge generated by the electric discharge machining and hindering the subsequent electric discharge machining can be removed more efficiently than before. Therefore, the electric discharge phenomenon that occurs between the electrode and the die material is performed more actively than before, which improves the processing speed.

Further, since the electric discharge machining electrode is smaller than the conventional one, the manufacturing period thereof can be greatly shortened as compared with the conventional one. Therefore, the processing of the slit groove can be started earlier than in the past, and thus the lead time in manufacturing the honeycomb structure forming die can be significantly shortened as compared with the conventional case.

The effect of shortening the lead time will be described more specifically with reference to FIG. In the same figure, the horizontal axis shows the elapsed schedule, and each process is shown in chronological order by arrows. The upper part shows a case of manufacturing a conventional large-sized (integrated type) electric discharge machining electrode, and the lower part shows a case of manufacturing a small electric discharge machining electrode 1 of this example.

As is known from the figure, in the conventional case, the manufacturing A of the electrode for electric discharge machining is 50 days, the manufacturing of the die material 80 and the processing of the supply hole (material processing) B are 15 days, and the slit groove processing is performed. C1 is 55 days. Since the material processing B can be performed in parallel with the manufacturing A of the electric discharge machining electrode, the manufacturing lead time of the honeycomb structure molding die is 10 times A + C1.
It was 5 days.

On the other hand, in the case of the present example, considering the case where four electric discharge machining electrodes 1 are used, the manufacture A1 to A4 of each electric discharge machining electrode 1 takes 7 days, and the die material 80 is used. And processing of the supply holes (material processing) B is 15 days, and slit groove processing C2 is 28 days. Here, the processing of the slit groove can be started at the time when the manufacturing A1 of one electric discharge machining electrode 1 and the material processing B are completed. Therefore, the manufacturing lead time of the mold for honeycomb structure molding of this example is B +
It will be 43 days of C2.

Therefore, in this example, the lead time can be shortened by about 60 days. The reason why the slit groove machining C2 period is shortened as compared with the conventional one is that the sludge elimination effect is improved as the machining liquid supply / discharge capacity is improved by the miniaturization of the machining surface, as described above. It is a big factor.

As described above, according to the present embodiment, it is possible to provide a method for manufacturing a honeycomb structure forming die, which can perform the processing of the slit groove with high accuracy and with a short lead time.

Embodiment 2 This embodiment is a specific example in which the order of a plurality of electric discharge machining in Embodiment 1 is changed. That is, in this example, the above 9
Each of the regions S1 to S9 is subjected to a unit machining in which electric discharge machining is performed to a depth of ¼ of the desired slit groove depth D (FIG. 1), and then this unit machining is repeated three more times to form the slit groove 82. Was processed to a desired depth D. In addition, the electric discharge machining electrode 1 was replaced with a new one for each of the above unit machining, and a total of four electrodes were used.

Further, in this example, the above unit machining is
The central region S5 located in the central portion of the above nine regions was first subjected to electric discharge machining, and then sequentially machined from the side closer to the central region. Specifically, in FIG. 7, S5, S
4, S6, S3, S7, S2, S8, S9 were processed in this order.

In the case of this example, the above-mentioned regions S1 to S9 are not grooved to a desired depth by one electric discharge machining, but the unit machining is repeated to deepen the groove depth. By this stepwise electric discharge machining, it is possible to suppress individual local machining variations and further improve the machining accuracy of the slit grooves.

Further, by performing the above-mentioned unit processing in the above-mentioned order, it is possible to make the change of the slit groove width and the like due to subtle processing variations substantially symmetrical. Therefore, the moldability at the time of molding a honeycomb structure using the obtained honeycomb structure molding die can be improved. Other than that, the same effects as those of the first embodiment can be obtained.

In each of the above embodiments, the case where the lattice shape of the slit groove is hexagonal is shown.
Similar effects can be obtained in other shapes such as a rectangular shape and an octagonal shape.

[Brief description of drawings]

FIG. 1A is a partially cutaway sectional perspective view of a honeycomb structure forming mold in Embodiment 1, and FIG.

FIG. 2 is an explanatory view showing the manufacturing procedure of the honeycomb structure forming mold in the first embodiment.

FIG. 3 is a perspective view of an electric discharge machining electrode according to the first embodiment.

FIG. 4 (a) In the first embodiment, there is no incomplete edge,
(B) Explanatory drawing which shows the specific example of having an imperfect edge.

FIG. 5 is an explanatory diagram showing a connection state between an electric discharge machining electrode and a machining fluid supply jig in the first embodiment.

FIG. 6 is an explanatory view showing an electric discharge machine according to the first embodiment.

FIG. 7 is an explanatory diagram showing a divided area for electric discharge machining according to the first embodiment.

FIG. 8 is an explanatory view showing a moving position of the electric discharge machining electrode in the first embodiment.

FIG. 9 is an explanatory diagram showing a lead time reduction effect in the first embodiment.

FIG. 10 is an explanatory view showing an electric discharge machining electrode in a conventional example.

[Explanation of symbols]

1. ． ． EDM electrode, 10. ． ． Processing surface, 5. ． ． Processing liquid supply jig, 6. ． ． Electrical discharge machine, 8. ． ． Mold for forming honeycomb structure, 80. ． ． Mold material, 81. ． ． Supply hole, 82. ． ． Slit groove, 84. ． ． Hole forming surface, 85. ． ． Groove forming surface,

─────────────────────────────────────────────────── ─── Continuation of the front page (56) Reference JP-A 63-28523 (JP, A) JP-A 8-252724 (JP, A) JP-A 57-8038 (JP, A) JP-A 58- 10428 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) B23H 9/00 B28B 3/26

Claims (4)

(57) [Claims] 1. A plurality of supply holes for supplying material and the supply holes
The material is formed into a honeycomb shape by connecting to the
For forming honeycomb structure having slit grooves for forming
In the method of manufacturing the mold, The processing of the above-mentioned slit groove is performed by cutting the groove forming surface of the die material with the groove.
Small size with a processing surface smaller than the area of the forming surface
By performing electric discharge machining multiple times using the electric discharge machining electrode
lineYes The grooved surface of the electric discharge machining electrode has a width
One area can be processed when it is divided into n areas in the direction
It has a size The above-mentioned electric discharge machining uses the above-mentioned n pieces of electric discharge machining electrodes.
Unit processing of processing each area to a predetermined depth
By repeating multiple times, Moreover, the unit processing is performed in the substantially central portion of the n areas.
The central region located at is first electric discharge machined, then
Process sequentially from the side closer to the central area Characterized by
A manufacturing method of a die for forming a honeycomb structure. 2.Plural supply holes for supplying material and the supply holes
The material is formed into a honeycomb shape by connecting to the
For forming honeycomb structure having slit grooves for forming
In the method of manufacturing the mold, The processing of the above-mentioned slit groove is performed by cutting the groove forming surface of the die material
Small size with a processing surface smaller than the area of the forming surface
By performing electric discharge machining multiple times using the electric discharge machining electrode
Done, Moreover, the machining surface of the electric discharge machining electrode contributes to machining.
All the parts that correspond to the grid shape of the above slit groove
Incomplete edges that do not form a grid
For forming honeycomb structure characterized by not having
Mold manufacturing method. 3.Plural supply holes for supplying material and the supply holes
The material is formed into a honeycomb shape by connecting to the
For forming honeycomb structure having slit grooves for forming
In the method of manufacturing the mold, The processing of the above-mentioned slit groove is performed by cutting the groove forming surface of the die material
Small size with a processing surface smaller than the area of the forming surface
It is possible to perform EDM multiple times using the EDM electrode. And by
Done, In addition, of the above-mentioned multiple electrical discharge machining, the second or subsequent electrical discharge
The above process is applied to the grid formed by the previous electrical discharge machining.
The above discharge so that at least one of the plane grids overlaps
Honeycomb characterized by moving the working electrode
A method for manufacturing a mold for forming a structure. 4. The method according to any one of claims 1 to 3,
A machining fluid for electrical discharge machining is supplied to the electrical discharge machining electrodes.
Is equipped with a jig for supplying the machining liquid.
The tool is equipped with two or more machining fluid outlets
And a method for manufacturing a honeycomb structure molding die.