JPH06104348B2 - End face sealing method for honeycomb formed body - Google Patents

Description

The present invention relates to a method for sealing an end face of a honeycomb formed body, and more specifically, to easily and surely using a thin film formed body having plasticity. The present invention relates to a sealing method capable of sealing the end face.

(Prior Art) A large number of through-holes having a rectangular cross section or a triangular shape continuous in a honeycomb shape through a thin porous partition wall, and one end face of the plurality of through-holes is sealed, for example, in every other vertical and horizontal directions. The honeycomb filter made of a sintered body, in which the other end surface of the through hole adjacent to the sealed through hole is sealed, is a fine particle carbon contained in the exhaust gas of various combustion equipment including automobile diesel engines. It is known as an exhaust gas purifying device that adsorbs and purifies the exhaust gas.

Such a honeycomb filter is obtained by adding clay or an organic binder to fine powder of carbides or nitrides of oxides such as cordierite, alumina, etc., silicon carbide, silicon nitride, etc., and then extrusion molding method or pipe binding method. To form a so-called checkered pattern by sealing every other end face of the honeycomb-shaped formed body by every other method, and then fired and formed under predetermined conditions. It

Among them, in the conventional method of sealing the end faces of the honeycomb-shaped molded body by, for example, leaving one end in the vertical and horizontal directions, a film impregnated with an adhesive resin is attached to one surface of the honeycomb-shaped molded body, and then the checkered pattern is formed. Make a hole in the film with a needle according to the through hole you want to seal in a pattern, immerse the end face of this holed honeycomb shaped body in a container filled with a slurry-like sealing material, apply vibration with a vibrator, and let the through hole A method in which a step of introducing a sealing material into both ends is performed on both end faces, and after the sealing material is cured under predetermined conditions, the film is peeled off,
Alternatively, one end surface of the honeycomb formed body is dipped in the slurry, and after sealing all the end surfaces, compressed air is sent from the other end surface to every other vertical and horizontal through holes to form a sealing portion formed on the one end surface. Then, after covering the other end surface with a thin film, compressed air is sent from the entire one end surface to open the thin film on the other end surface of the through hole opened at the one end surface, and the other end surface is the same as above. There is a method in which the thin film is immersed in a slurry and the other end surface of the through hole opened by compressed air is sealed and baked.

(Problems to be Solved by the Invention) However, in any of the above-described conventional methods, since it is necessary to make the sealing material into a slurry state, it takes time and labor,
Further, the thickness of the sealing material when the slurry-like sealing material is introduced into the through hole to be sealed is not constant because it varies from one through hole to another. Therefore, particularly when the thickness of the sealing material is thin, the strength of the honeycomb-shaped molded body after forming the sealing portion will be poor, and the heat resistance of the sealing material will also be poor. As a result, there is a problem of thermal shock destruction when heated for removing the fine carbon adhering to the partition walls by burning.

Further, usually, the sealing material is required to be filled so as to seal the end surface of the through hole so that the fluid that does not pass through the porous partition wall does not flow out of the molded body as it is. When sealing with the slurry-like sealing material, there may be a gap between the partition wall and the sealing material, in which case there is a problem that the fluid cannot be completely filtered. .

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned problems, and to provide a sealing method capable of reliably sealing the end face of a honeycomb-shaped molded body and easily performing the work.

[Structure of the Invention] (Means for Solving Problems) The end face sealing method for a honeycomb-shaped molded body according to the present invention is a honeycomb-shaped molded body in which a large number of through holes are adjacent to each other in the axial direction with a thin partition wall therebetween. A method of sealing the end faces of a large number of through holes, after closing the end faces of the through holes to be the opening with a mask material, the entire end face of the honeycomb-shaped molded body is covered with a thin film molded body having plasticity, Then, by pressing the entire top surface of the thin film molded body with a pressing tool, the plastic thin film molded body is provisionally press-fitted into the end surface of the through hole to be the sealing portion, and then the mask material is coated with the mask material. It is characterized in that the thin film formed body is removed together with the part of the thin film formed body, and the entire end surface of the honeycomb formed body is directly flat-pressed by a pressing tool to press the thin film formed body into the end surface of the through hole.

Hereinafter, the sealing method of the present invention will be described in more detail with reference to the drawings.

FIG. 1 is a perspective view showing an example of a honeycomb-shaped molded body. 2 to 4 are views showing an embodiment of the present invention, FIG. 2 is a plan view showing a state in which a mask material is in contact, and FIG. 3 shows an end face in this embodiment. FIG. 4 is a schematic cross-sectional view for explaining the stopping step, and FIG. 4 is a plan view showing a state where the end faces of the honeycomb-shaped molded body are sealed every other length and width.

In the figure, reference numeral 1 denotes a honeycomb-shaped molded body which is molded from an inorganic raw material as a base material in the present invention and has a large number of through holes in a honeycomb shape. The honeycomb-shaped molded body is an oxide such as cordierite or alumina, or silicon carbide. Clay or an organic binder is added to fine powder of carbide or nitride such as silicon nitride, and the mixture is molded by a conventional method such as extrusion molding. 1a
Shows one end face of the honeycomb formed body, that is, one end face of a large number of through holes, and 1b shows the other end face. Reference numeral 2 indicates a mask material used in the sealing method of the present embodiment, and reference numeral 3 indicates a thin film molded body having plasticity.

In this embodiment, as shown in FIG. 2, first, in the one end face 1a, the through-hole end face 11a serving as an opening (hatched portion).
And a through-hole having a width x defined by the following equation: a <x ≦ a + b (where a is the hole width of the through-hole of the honeycomb formed body, and b is the thickness of the partition wall). The mask material 2 having the same shape as the cross-sectional shape of 11 is brought into contact with the end surface 11a of the through hole to be closed.

Next, as shown in FIG. 3 (a), the entire end face 1a of the honeycomb-shaped molded body is covered so that the thin film molded body 3 having plasticity is laminated on the upper surface of the mask material 2. Then, if pressure is applied from the upper surface of the plastic molded body 3 using a pressure tool 4 such as a roller or a hydraulic press tool, as shown in FIG. A portion 3a of the thin film molded body 3 is provisionally press-fitted into the end surface 11b of the through hole that is not blocked by the material, that is, the thickness 3y of the mask material is left, and the part 3a is press-fitted into the end surface 11b.

Next, when the mask material 2 is removed, the thin-film molded body 3b that covers the mask material 2 is separated from the thin-film molded body 3a that is temporarily press-fitted into the through hole, and is removed together with the mask material 2. Then, the state becomes as shown in FIG. 3 (c). And
As shown in FIG. 3 (d), when a pressing tool 4 such as a roller or a flat plate is used to directly press the end face 1a of the honeycomb-shaped molded product so as to be a flat surface, the thin-film molded product temporarily press-fitted. 3a is completely press-fitted into the through hole end surface 11a to form a sealing portion.

Then, as shown in FIG. 4, one end surface 1a of many through holes is formed.
The thin film molded bodies 3a (hatched portions), which are sealing materials, are press-fitted in every other vertical and horizontal directions.

Furthermore, by applying the same method, it is possible to seal the other end surface of each through hole 11 that is open at one end surface in the other end surface 1b of a large number of through holes and seal the other end surface 1b every other length and width. it can.

Here, the mask material 2 has the above-described size and shape, and is made of a metal or plastic such as aluminum, copper, vinyl chloride, polyethylene, or hard rubber and has a thickness of about 10 to 500 μm. In this case, when the thickness is too thick, it is difficult to press-fit the thin film molded body, while when it is too thin, the thin film molded body is destroyed by pressurization.

The thin film molded body 3 is made of cordierite, alumina, silicon carbide, silicon nitride or the like by an extrusion molding method, a doctor blade method or the like, has plasticity, and has a thickness of about 50 μm to 2 mm. Those are preferable. Since this thin film molded body serves as a sealing material, when it is too thin, the strength of the honeycomb-shaped molded body after forming the sealing portion is poor as described above, and when it is too thick, This is because the filtration function of the partition wall will be hindered.

5 and 6 show another embodiment of the present invention, FIG. 5 is a plan view of a mask material used in this embodiment, and FIG. 6 describes a step of sealing an end face in this embodiment. FIG.

In this embodiment, as shown in FIG. 6, first, one end face of the honeycomb formed body 1 formed to have a large number of through holes 11 having a substantially square cross section, that is, one end face of a large number of through holes.
1a (FIG. 6 (a)) has the following equation; a <x ≦ a + b (where a is
Is the hole width of the through-hole of the honeycomb formed body, and b is the thickness of the partition wall. ), So that the plurality of ribbons 2'a having the width x defined by) have a gap having the same shape as the through-hole cross-sectional shape, that is, the shape of the gap 2'b is substantially the same as the through-hole cross-sectional shape. Mask material 2'formed by crossing
The end face 1a is brought into contact with the end face 11a of the through hole which is to be the sealing portion and the end face 11b of the through hole and the gap 2'b of the mask material, as shown in FIG. 6 (b).

Then, from the upper surface of the abutting mask material 2 ', the entire one end face 1a is made of, for example, cordierite, alumina, silicon carbide, silicon nitride or the like as in the above-described embodiment, using an extrusion molding method or a doctor blade method. End surface of the through-hole which is opened by covering with a plastic thin film molded body (not shown) molded by a conventional method such as the above, and then pressing the entire upper surface of the thin film molded body with a pressing tool such as a roller or a hydraulic press tool. A portion of the plastic thin film molded body corresponding to the end face is press-fitted into 11b.

Then, when the above-mentioned mask material 2'is removed, the thin film molded body in the portion covering the mask material 2'is also separated from the thin film molded body in the portion press-fitted into the through hole. Removed with 2 '.

Next, as in the above-mentioned embodiment, the honeycomb formed body is directly pressed by a pressing tool such as a roller or a flat plate.

Thereafter, the mask material 2'is moved in the directions of arrows p1 and p2 shown in FIG. 6 (c), and a thin film molded body as a sealing material is press-fitted into the end surface 11b of the through hole to be the sealing portion in the same manner as above.

Then, if the mask material 2'is removed from the abutting one end surface 1a, a thin film molded body (hatched portion) as a sealing material is formed on the one end surface 1a of a large number of through holes as shown in FIG. 6 (d). Will be enclosed every other vertical and horizontal.

Furthermore, by applying the same method, it is possible to seal the other end surface of each through hole 11 that is open at one end surface in the other end surface 1b of a large number of through holes and seal the other end surface 1b every other length and width. it can.

Therefore, according to this embodiment, unlike the above embodiment,
It is not necessary to individually close the through holes that will be the openings, and work efficiency is improved.

The moving direction, the moving amount, and the moving order of the mask material 2'in this case are merely examples. The point is that the mask material gap 2'b should be matched with the end surface 11b of the through hole to be sealed and the thin film molded body as the sealing material should be press-fitted.

Further, the ribbon 2'a constituting the mask material 2'is made of metal or plastic as a material, and is processed into a ribbon shape, that is, a short strip shape, as in the above embodiment.

Furthermore, in each of the above-mentioned embodiments, the shape of the through hole is described as an example of a substantially square shape, but even if the shape of the through hole is a quadrangle such as a rectangle or a rhombus or a triangle, the shape of the mask material or It goes without saying that the sealing method according to the present invention can be applied if the gaps of the mask material have the same shape.

[Effects of the Invention] As described above, according to the end face sealing method for a honeycomb formed body of the present invention, the end face is sealed only by press-fitting a plastic thin film formed body as a sealing material through a mask material. And the work can be performed easily, the thickness of the sealing material can be made constant, and moreover, the end surface of the through hole can be surely formed so that no gap is formed between the sealing material and the partition wall. Can be sealed.

[Brief description of drawings]

FIG. 1 is a perspective view showing an example of a honeycomb-shaped molded body. 2 to 4 are views showing an embodiment of the present invention, FIG. 2 is a plan view showing a state in which a mask material is in contact, and FIG. 3 shows an end face in this embodiment. FIG. 4 is a schematic cross-sectional view for explaining the step of stopping, and FIG. 4 is a plan view showing a state where the end faces of the honeycomb-shaped molded body are sealed every other length and width. 5 and 6 show another embodiment of the present invention, FIG. 5 is a plan view of a mask material used in this embodiment, and FIG. 6 describes a step of sealing an end face in this embodiment. FIG. 1 …… Honeycomb shaped body, 2,2 ′ …… Mask material, 3 ……
Thin film molded body, 4 ... Pressure tool, 11 ... Through hole.

Claims (1)

[Claims] 1. A method for sealing the end faces of a large number of through holes of a honeycomb-shaped molded body in which a large number of through holes are adjacent to each other in the axial direction across thin partition walls, the end faces of the through holes serving as openings. After closing with a mask material, the entire end surface of the honeycomb molded body is covered with a thin film molded body having plasticity, and then the entire upper surface of the thin film molded body is pressed with a pressing tool to form a through hole to be a sealing portion. Tentatively press-fit the plastic thin film molded body to the end surface of the, then remove the mask material together with the thin film molded body of the portion covering the mask material, further, by a pressing tool the entire end surface of the honeycomb-shaped molded body A method for sealing an end face of a honeycomb-shaped molded body, which comprises directly pressurizing a flat surface and press-fitting the thin-film molded body into the end surface of the through hole.