JP2603510B2 - Method for sealing end face of honeycomb-shaped molded body - Google Patents

Description

The present invention relates to a method for sealing an end face of a honeycomb-shaped formed body,
More specifically, the present invention relates to a sealing method capable of easily and reliably sealing the end face by using a plastic thin film molded body.

[Conventional technology]

One end face of a through-hole of a honeycomb-shaped formed body having a large number of square-shaped or triangular-shaped through-holes continuous in a honeycomb shape through a porous thin partition wall is filled with a plug material, for example, every other length and width. A honeycomb filter made of a sintered body in which the other end surface of the through hole adjacent to the sealed through hole is similarly filled with a plug material and sealed is used for various kinds of combustion including a diesel engine of an automobile. It is known as an exhaust gas purifying apparatus that collects, filters, and removes fine carbon contained in exhaust gas of equipment.

Such a honeycomb filter is a cordierite, an oxide such as alumina, carbon silicon, and a fine powder of a carbide or nitride such as silicon nitrogen, adding a viscosity or organic binder to a fine powder,
Thereafter, a honeycomb-shaped formed body is formed by an ordinary method such as an extrusion forming method or a pipe bundling method, and then the both end faces of the honeycomb formed body are sealed, for example, every other length and width to form a so-called checkered pattern. Then, it is manufactured by firing and molding under predetermined conditions.

Among them, the conventional method of sealing the end face of the honeycomb-shaped molded body, for example, every other length and width, is to paste a film impregnated with an adhesive resin on one side of the honeycomb-shaped molded body, and then Drill a hole in the film with a needle according to the through hole that you want to seal so as to form a checkerboard pattern, immerse the end face of this drilled honeycomb-shaped molded body in a container with a slurry-like plug material, and vibrate with a vibrator to penetrate A method in which a step of introducing a plug material into the hole is performed on both end faces, and the film is peeled off after curing the plug material under predetermined conditions.
Alternatively, one end face of the honeycomb-shaped formed body is immersed in the slurry, and after sealing the entire end face, compressed air is sent from the other end face to every other vertical and horizontal through hole to form a sealing portion formed on one end face. After that, the other end face is coated with a thin film, and then compressed air is fed from the entirety of the one end face to open the thin film on the other end face of the through hole that is open at one end face, and the other end face is the same as described above. Immersion in slurry, sealing the other end surface of the through hole in which the thin film is opened by compressed air, and baking.

[Problems to be solved by the invention]

However, in any of the above-mentioned conventional methods, when a slurry-like plug material is introduced into a through hole to be sealed, the thickness of the plug material differs for each through hole and cannot be constant. Therefore, in particular, when the thickness of the plug material is small, the strength of the honeycomb formed body after forming the sealing portion is inferior, and the heat resistance of the plug material is also inferior, and as a result, In addition, there is a problem that thermal shock destruction occurs when heating is performed for burning and removing fine carbon particles adhering to the partition walls.

Further, it is generally required that the plug material is filled so as to seal the end face 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 without being filtered. However, when sealing with the slurry-like plug material described above, a gap may be formed between the partition wall and the plug material, and in that case, there is a problem that the fluid cannot be completely filtered. is there.

The present inventor has proposed a method for sealing the end face of a honeycomb-shaped formed body that solves such a problem. First, a mask material is brought into contact with an end face of a through hole to be an opening in advance and closed, and then the sealing is performed. Japanese Patent Application No. 62-299833 (JP-B-6-104348) discloses a method of press-fitting a plastic thin film molded body into the end face of a through hole serving as a part.
No.).

However, this method uses a metal or plastic material such as aluminum, copper, polyethylene, or hard rubber as a mask material. May move to the through hole serving as the sealing portion with the movement of the roller, and the thickness of the thin film molded article to be pressed into the through hole serving as the sealing portion may not be constant. Was.

An object of the present invention is to solve the above-mentioned problems and to provide a sealing method capable of securely sealing an end face of a honeycomb-shaped formed body and easily performing the work.

[Means for solving the problem]

The method for sealing an end face of a honeycomb formed body according to the present invention is a method for sealing an end face of a through hole of a honeycomb formed body having a large number of through holes formed in the axial direction by thin partition walls. After closing the end face of the hole with a thin film-shaped mask material, the entire end face of the honeycomb-shaped formed body is covered with a plastic thin film formed body, and then corresponds to the shape of the through-hole or is similar to the corresponding shape. Having a shape, the area of which is 100 to 500% of the area of the through-hole. The plastic thin film molded body is pressed into the end face of the through-hole to be a sealing portion by pressing with a pressing tool, and then the Mask material,
A method for sealing an end face of a honeycomb-shaped formed body, comprising removing the mask material together with a portion of the thin-film formed body covering the mask material.

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 one example of a honeycomb formed body to be sealed in the present embodiment. The end face 1a of the through hole of the present honeycomb formed body is formed of a square through hole 11 and a partition wall 12. The through hole end face 11a is a through hole serving as an opening, and the through hole 11b is a through hole serving as a sealing portion. This embodiment is an example in which a sealing portion is arranged in a checkered pattern.

Next, the mask 2 is brought into close contact with the through-hole end face 1a as shown in FIG. The mask 2 is formed of a thin film, and has a through portion 21 corresponding to a portion corresponding to the end surface 11b of the through hole in FIG.

FIG. 3 is a schematic sectional view showing a step of press-fitting the sealing portion into the honeycomb formed body 1 in the present embodiment.
FIG. 1A is a schematic cross-sectional view in which a mask 2 is arranged on an end face of a honeycomb-shaped molded body 1, a thin-film-shaped plastic molded body 3 is placed thereon, and a pressing tool 4 is further arranged. .

FIG. 3 (b) shows that the plastic molding 3
FIG. 4 is a schematic cross-sectional view showing a state in which is pressed and pressed into a through-hole end face 11b of a honeycomb formed body.

Then, the pressing tool 4 moves to another through-hole end face 11b and is pressurized. Similarly, all the desired through-hole end faces 11b are moved.
After sealing b, the mask 2 and the remaining molded body 3 are removed, and the sealing is completed.

At this time, some of the pressing tools 4 are arranged so as not to contact with each other, and the plurality of through-hole end faces 11b can be simultaneously sealed. The cross-sectional shape of the pressing tool must correspond to the shape of the end face of the through-hole or have a shape similar to the corresponding shape. It needs to be 100-500%. The reason is that first, if the cross-sectional shape of the pressing tool corresponds to the shape of the end face of the through hole or is not similar to the corresponding shape, the amount of the sealing material supplied to the end face of the through hole is reduced. This is because the thickness of the sealing material becomes uneven due to the change.

If the area is smaller than 100% of the area of the through-hole, pressure is not applied to the entire molded article on the end face of the through-hole, and the adhesion between the molded article and the honeycomb becomes poor.
If the ratio is larger than%, not only is the molded body flow into the opening than necessary, and not only a large pressing force is required, but also the thickness of the sealing material becomes extremely large.

The area of the cross section of the pressing tool is, of course, in a range not exceeding the total area of the corresponding through hole area and the cross sectional area of the peripheral partition wall forming the through hole. That is, it is important that the portion other than the corresponding through-hole should not be covered.

The mask material is preferably a thin film metal or resin that has a large elastic coefficient and does not plastically deform due to the pressure of the pressing tool. For example, stainless steel, aluminum, titanium, copper, polyester film, polyethylene, nylon, fluororesin and the like can be used.

Further, the thickness of the mask is preferably 0.01 to 2 mm. If it is less than 0.01 mm, it will be ruptured by pressure, and it will be difficult to remove unnecessary thin film moldings together with the mask material. This is because the molded body invaded in the hole is removed at the same time when the mask is removed.

The thin film molded body 3 is made of cordierite, alumina, silicon carbide, silicon nitride, or the like, and is formed by an extrusion molding method, a doctor blade method, or the like, and has plasticity and a thickness of about 0.05 to 2 mm. preferable. Since this thin film molded article is to be a plug material, if it is too thin, the strength of the honeycomb molded article after molding the sealing portion by the method described above is inferior, and if it is too thick, This is because the molded body is not smoothly pressed into the through hole as a plug material.

FIG. 4 shows another embodiment of the present invention and is a view for explaining a step of sealing an end face in the present embodiment.

In this embodiment, as shown in FIG. 4, first, one end face 1a (FIG. 4 (a)) of a honeycomb formed body 1 formed so as to have a large number of through holes 11 having a substantially square cross section is provided. A <x ≦ a + b (where a is the width of the through-hole of the honeycomb-shaped formed body and b is the thickness of the partition wall), a plurality of ribbons 2 ′ having a width x defined by the following formula: a having a gap having the same shape as the cross-sectional shape of the through-hole, that is, the mask material 2 'formed by intersecting such that the shape of the gap 2'b is substantially the same as the cross-sectional shape of the through-hole. In FIG. 4A, an arbitrary through-hole end face 11b serving as a sealing portion and an arbitrary mask material gap 2'b are brought into alignment with each other and brought into contact as shown in FIG. 4 (b).

Next, from the upper surface of the abutting mask material 2 ', the entire end surface 1a is, for example, cordierite, similarly to the above-described embodiment.
Alumina, silicon carbide, silicon nitride and the like are used as materials, and are covered with a plastic thin film molded body (not shown) formed by extrusion molding, normal pressure such as a doctor blade method, and then corresponding to the through hole 11b on the upper surface of the thin film molded body. The portion is pressurized with the pressurizing tool, and the portion of the plastic thin film molded body corresponding to the end face is press-fitted into the end face 1 of the opened through hole.

When the mask material 2 'is removed, an excess thin film formed body covering the mask material 2' is also removed together with the mask material 2 '.

Next, similarly to the above-described embodiment, the honeycomb formed body is directly flat-pressed with 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. 4 (c), and a thin film molded body as a plug material is pressed into the through-hole end face 11b serving as a sealing portion in the same manner as in the above-described process. .

When the mask material 2 'is removed from the one end face 1a where the mask material 2' has come into contact, as shown in FIG. 4 (d), a thin film molded body (hatched portion) as a plug material is formed on one end face 1a of a large number of through holes. It will be press-fit every other length and width.

Further, the same method is applied to the other end surface 1b of the large number of through holes.
In this case, the other end surface of each through hole 11 opened at one end surface can be sealed, and the other end surface 1b can be sealed every other length and width.

Therefore, according to the present embodiment, unlike the above-described embodiment, it is not necessary to individually close the through holes serving as the openings in advance, and the working efficiency is improved.

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

The ribbon 2'a forming the groove in the mask material 2 'is
As in the previous embodiment, it is made of a thin film of stainless steel, aluminum, titanium, copper, polyester, nylon, fluororesin or the like, and is processed into a ribbon shape, that is, a short shape.

Further, as still another embodiment of the present invention, as shown in FIG. 5, an area having an area capable of covering the entire end face of the honeycomb formed body is provided at a position corresponding to a through hole serving as a sealing portion. Hole 2 ″ b having the same shape and the same area as the cross-sectional shape of the through hole
An embodiment using an integrated mask material 2 ″ having the following may be used.

In this case, not only the holes 2 ″ b provided at the locations corresponding to all the sealing portions as shown in FIG.
Using a mask material in which a hole is perforated at a portion corresponding to a part thereof, it can be appropriately moved and filled with a plug material at the end of the desired through hole and sealed as in the above-described embodiment. .

Further, in each of the above embodiments, the shape of the through-hole has been described as being substantially square. However, even when the shape of the through-hole is a rectangle or a triangle such as a rectangle or a rhombus, the shape of the mask material or the mask may be used. It goes without saying that the sealing method according to the present invention can be applied if the gaps and holes of the material have the same shape.

〔The invention's effect〕

As described above, the end face sealing method of the honeycomb formed article of the present invention corresponds to the shape of the through hole or has a shape similar to the corresponding shape, and the area is 100 to 100 of the area of the through hole. This is a method of sealing an end face in which a thin film molded article having plasticity is press-fitted as a plug material through a mask material using a pressing tool that is 500%, which not only facilitates work but also reduces the thickness of the plug material. The end surface of the through hole can be reliably sealed so that no gap is formed between the plug member and the partition wall.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an example of a honeycomb formed body. FIG. 2 is a plan view showing a state in which the mask material is abutted, FIG. 3 is a schematic sectional view for explaining a step of sealing an end face in the present embodiment, and FIG. FIG. 3 is a schematic cross-sectional view in which a mask is arranged on an end face of a honeycomb-shaped formed body, a thin-film-shaped plastic formed body is placed thereon, and a pressing tool is further arranged. FIG. 3 (b) is a schematic cross-sectional view showing a state where the plastic molded body is pressed by the pressing tool and pressed into the end face of the through-hole of the honeycomb-shaped molded body. FIG. 4 shows another embodiment of the present invention and is a view for explaining a step of sealing an end face in the present embodiment. FIG. 5 is a plan view of a mask material used in still another embodiment of the present invention. DESCRIPTION OF SYMBOLS 1 ... Honeycomb molded body 2, 2 ', 2 "... Mask material 3 ... Thin film molded body 4, ... Pressing tool 11 ... Through hole, 12 ... Partition wall 21 ... Through hole of mask material

Claims (1)

(57) [Claims] 1. A method for sealing an end face of a through-hole of a honeycomb-shaped formed body having a large number of through-holes formed in the axial direction by thin partition walls, wherein the end face of the through-hole serving as an opening is formed into a thin film-shaped mask material. After closing, the entire end face of the honeycomb-shaped formed body is covered with a thin-film formed body having plasticity, and then has a shape corresponding to or similar to the shape of the through-hole, and the area of the through-hole is The plastic thin film molded body is pressed into the end face of the through-hole serving as a sealing portion by pressing with a pressing tool that is 100 to 500% of the area of
A method for sealing an end face of a honeycomb formed body, comprising removing the mask material together with a portion of the thin film formed body which covers the mask material.