WO2011142292A1

WO2011142292A1 - Mask for sealing honeycomb structure, and sealing method for honeycomb structure using same

Info

Publication number: WO2011142292A1
Application number: PCT/JP2011/060550
Authority: WO
Inventors: 康輔魚江; 照夫小森; 正春森; 智嗣大平
Original assignee: 住友化学株式会社
Priority date: 2010-05-11
Filing date: 2011-05-02
Publication date: 2011-11-17
Also published as: JP4852668B2; JP2011255672A

Abstract

Disclosed is a mask which can be use for sealing cells in a honeycomb structure. The mask has a plurality of first through holes which pass through the mask from one end surface to the other end surface, and the area of the openings of the first through holes at one end surface is smaller that the area of the openings of the first through holes at the other end surface.

Description

Honeycomb structure sealing mask and honeycomb structure sealing method using the same

The present invention relates to a mask used for sealing a honeycomb structure and a method for sealing a honeycomb structure using the mask.

Conventionally, honeycomb filter structures have been widely known for DPF (Diesel particulate filter) and the like. This honeycomb filter structure has a structure in which one end side of a part of cells of a cell structure including a large number of through holes is sealed with a sealing material, and the other end side of the remaining cells is sealed with a sealing material.

A mask is used to seal a predetermined cell among many cells of the honeycomb structure. There are two types of masks for such applications. One is a type in which a through hole is provided in advance at a location corresponding to a cell to be sealed. The other is a type in which a through hole is not provided in advance, and a through hole is provided by a laser or the like at a location corresponding to a cell to be sealed after being attached to the end face of the honeycomb structure. The following Patent Documents 1 and 2 describe a method for sealing a honeycomb structure using a mask.

JP 2004-290766 A JP 2008-132749 A

By the way, the mask of the type in which the through holes are provided in advance needs to be aligned with the honeycomb structure. In particular, when the honeycomb structure is a sintered body manufactured through a drying process or a firing process, such as DPF, or a green molded body before firing, the through-holes of the mask are caused by the shrinkage or deformation of the honeycomb structure in the manufacturing process. And the cell to be sealed become more difficult to align. Some DPFs have a narrow cell pitch (for example, about 1.1 to 2.8 mm). Even if the through-holes of the mask can be appropriately arranged on a part of the end face of the honeycomb structure, the other parts are not displaced. It may occur.

The present invention has been made in view of the above problems, and can be easily aligned with the end face of the honeycomb structure, and uses a mask useful for reliably sealing a predetermined cell. The purpose is to provide a sealing method.

The mask according to the present invention is used for sealing a cell of a honeycomb structure, and has a plurality of first through holes penetrating from one surface of the mask to the other surface, and the first penetration on the other surface. The opening area of the hole is smaller than the opening area of the first through hole on one surface.

The mask of the present invention is used in a state where the other surface of the mask (the surface with the smaller opening area) is in contact with the end surface of the honeycomb structure. According to the mask, by reducing the opening area of the first through hole on the other surface, the sealing material can be passed through the first through hole even if the position of the first through hole and the position of the cell opening are slightly shifted. It can be supplied into a predetermined cell. Further, the mask has an advantage that sufficient rigidity is easily ensured as compared with a mask having a large opening area of the entire first through hole.

In the present invention, the first through hole may have a tapered portion whose opening area continuously decreases from one surface to the other surface, or the opening area from one surface to the other surface. May have a stepped portion that discontinuously shrinks.

The first through hole preferably has an opening area of 0.03 mm ² or more on the other surface and less than 90% of the opening area of the cells of the honeycomb structure to be sealed by the first through hole. By setting the opening area of the first through hole to be less than 90% of the opening area of the cell to be sealed, even if the position of the first through hole and the position of the cell opening are slightly shifted, The sealing material can be reliably supplied in a predetermined cell. By setting the opening area of the first through hole to 0.03 mm ² or more, the sealing material can easily pass through the first through hole, and a predetermined amount of the sealing material can be easily supplied into the cell.

The mask according to the present invention has a plurality of second through-holes penetrating in the thickness direction of the mask in a portion in contact with the peripheral edge of the end face of the honeycomb structure in a region in contact with the end face of the honeycomb structure in use. May further be included. In this case, the second through holes are provided at an interval narrower than the cell pitch of the honeycomb structure, the opening area is 0.03 mm ² or more, and the opening area of the cells to be sealed by the first through holes Is preferably less than 60%.

In the peripheral part of the honeycomb structure, the shape of the cell may be different from other parts due to the presence of the outermost layer forming the side surface of the honeycomb structure. For example, in the case of a honeycomb structure in which the shape of the outermost layer is a cylindrical shape and cells having a square cross-sectional shape are provided therein, a complete cell having a square cross-sectional shape and an incomplete cell in the peripheral portion are formed. Exists.

The second through-hole is useful for completely sealing the incomplete cell as described above and, if necessary, the cell adjacent thereto. That is, the opening area of the second through-hole is limited to less than 60% of the opening area of the cell (complete cell) to be sealed by the first through-hole, while the arrangement of the second through-hole is limited to that of the honeycomb structure. By making the interval narrower than the cell pitch and increasing the number sufficiently, the sealing material can be appropriately supplied to the cell to be sealed through the second through hole. Further, by setting the opening area of the second through hole to 0.03 mm ² or more, the sealing material can easily pass through the second through hole, and a predetermined amount of the sealing material can be easily supplied into the cell.

The present invention provides a method for sealing the opening of a predetermined cell of a honeycomb structure using the mask. That is, the present invention is a method for sealing cells of a honeycomb structure,
(A) placing a mask on one end face of the honeycomb structure;
(B) supplying a sealing material through the first through hole of the mask to the opening of the cell to be sealed on one end face of the honeycomb structure;
The mask has a plurality of first through holes penetrating from one side to the other side, and the opening area of the first through hole on the other side is larger than the opening area of the first through hole on the one side There is provided a sealing method for arranging the mask so that the other side of the mask is in contact with the end face of the honeycomb structure in the step (a).

According to the above-described sealing method, alignment with the end face of the honeycomb structure can be easily performed, and a predetermined cell can be sealed more reliably as compared with the conventional method.

When incomplete cells exist at the peripheral edge of the honeycomb structure, the sealing method can be configured as follows. That is, the mask further includes a plurality of second through-holes penetrating in the thickness direction of the mask in a portion that contacts the peripheral edge of the end face of the honeycomb structure in a region that contacts one end face of the honeycomb structure. And the second through holes are provided at an interval narrower than the cell pitch of the honeycomb structure, the opening area is 0.03 mm ² or more, and the opening area of the cell to be sealed by the first through holes It can be less than 60%. In the step (b), the sealing material is supplied to the opening of the cell to be sealed at the peripheral edge of the end face of the honeycomb structure through the second through hole of the mask.

The sealing method may further include a step of sealing the other end surface after the step of sealing one end surface of the honeycomb structure. After sealing both the end faces of the honeycomb structure, a honeycomb filter structure can be obtained by performing steps such as drying and firing as necessary. That is, the sealing method is
(C) placing another mask on the other end face of the honeycomb structure;
(D) A step of supplying a sealing material to the opening of the cell to be sealed on the other end face of the honeycomb structure through the third through hole of the other mask may be further provided. In this case, the other mask has a plurality of third through holes penetrating from one surface to the other surface, and the opening area of the third through hole on the other surface is the opening of the third through hole on the one surface. The mask is arranged so that the other side of the mask is in contact with the end face of the honeycomb structure in the step (a).

When incomplete cells exist at the peripheral edge of the honeycomb structure and the incomplete cells are sealed also on the other end face, the sealing method can be configured as follows. That is, the other mask has a plurality of fourth penetrations penetrating in the thickness direction of the mask in a portion of the region contacting the other end face of the honeycomb structure and contacting the peripheral edge of the end face of the honeycomb structure. The fourth through-holes are provided at intervals narrower than the cell pitch of the honeycomb structure, the opening area is 0.03 mm ² or more, and the cells to be sealed by the third through-holes are further provided. In the step (d), a sealing material is supplied through the fourth through hole of the mask to the opening of the cell to be sealed at the peripheral edge of the end face of the honeycomb structure.

According to the present invention, alignment with the end face of the honeycomb structure can be easily performed, and a predetermined cell can be more reliably sealed as compared with the conventional case.

FIG. 1 (a) is a perspective view showing an example of a honeycomb structure, and FIG. 1 (b) is a partially enlarged view of FIG. 1 (a). 2A is a perspective view showing an embodiment of a mask according to the present invention, and FIG. 2B is a partially enlarged view of FIG. FIG. 3 is a partial cross-sectional view taken along the line III-III in FIG. FIGS. 4A and 4B are partial cross-sectional views showing other aspects of the first through hole included in the mask according to the present invention. FIG. 5 is a schematic cross-sectional view showing an example of a sealing device. FIG. 6 is a view taken along arrow VI-VI of the sealing device of FIG. FIG. 7A is a perspective view showing another embodiment of the mask according to the present invention, and FIG. 7B is a partially enlarged view of FIG. FIG. 8A is a partial end view for explaining the operation of the sealing device of FIG. 6, and FIG. 8B is a partial cross-sectional view subsequent to FIG. 9A is a partial cross-sectional view subsequent to FIG. 8B, and FIG. 9B is a partial cross-sectional view subsequent to FIG. 9A. FIG. 10A is a partial cross-sectional view subsequent to FIG. 9B, and FIG. 10B is a partial cross-sectional view subsequent to FIG. 11A is a partial cross-sectional view subsequent to FIG. 10B, and FIG. 11B is a partial cross-sectional view subsequent to FIG. 11A. FIG. 12 is a partial cross-sectional view showing a state in which an elastic plate enters the first through hole of the mask according to the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. First, prior to the description of the mask according to the present invention, the honeycomb structure will be described.

(Honeycomb structure)
As shown in FIG. 1A, the honeycomb structure 1 is a cylindrical body in which a large number of cells 1a are arranged substantially in parallel. The cell 1a penetrates from one end face of the honeycomb structure 1 to the other end face. The cross-sectional shape of the cell 1a is a square as shown in FIG. The plurality of cells 1a are arranged in a square arrangement in the honeycomb structure 1 so that the central axis of the cells 1a is located at the apexes of the squares as viewed from the end face. The size of the square of the cross section of the cell 1a can be, for example, 0.8 to 2.5 mm on a side, and the opening area is about 0.6 to 7.0 mm ² (more preferably 0.8 to 6.0 mm). ² ). The cell pitch of the honeycomb structure 1 can be set to 1.1 to 2.8 mm. Note that the cell pitch means the distance between the centers of two adjacent cells, and in the honeycomb structure 1, is the length L shown in FIG.

In the honeycomb structure 1, the shape of the outermost layer 1c forming a side surface is a cylindrical shape, and as described above, the cell 1a having a square cross-sectional shape inside thereof (hereinafter referred to as “complete cell 1a” or simply “cell 1a”). .) In addition to this, the honeycomb structure 1 has cells 1b (hereinafter referred to as “incomplete cells 1b” or simply “cells 1b”) whose cross-sectional shape is not square at the peripheral edge thereof. As shown in FIG. 1B, the shape of the incomplete cell 1b is not constant but varies depending on the location.

The length in the direction in which the through holes constituting the

cells

1a and 1b of the honeycomb structure 1 extend is not particularly limited, but may be, for example, 40 to 350 mm. Further, the outer diameter of the honeycomb structure 1 is not particularly limited, but may be, for example, 100 to 320 mm.

The material of the honeycomb structure 1 is not particularly limited, but a ceramic material is preferable from the viewpoint of high temperature resistance. Examples of the ceramic material include alumina, silica, mullite, cordierite, glass, oxides such as aluminum titanate, silicon carbide, silicon nitride, and metal. The aluminum titanate can further contain magnesium and / or silicon. Such a honeycomb structure 1 is usually porous.

Further, the honeycomb structure 1 may be a green molded body (unfired molded body) that becomes a ceramic material as described above by firing later. A green molded object contains the inorganic compound source powder which is a ceramic raw material, organic binders, such as methylcellulose, and the additive added as needed.

For example, in the case of a green molded body of aluminum titanate, the inorganic compound source powder includes an aluminum source powder such as α-alumina powder, and a titanium source powder such as anatase-type or rutile-type titania powder. Furthermore, magnesium source powders such as magnesia powder and magnesia spinel powder and / or silicon source powders such as silicon oxide powder and glass frit can be included.

Examples of the organic binder include celluloses such as methylcellulose, carboxymethylcellulose, hydroxyalkylmethylcellulose, and sodium carboxymethylcellulose; alcohols such as polyvinyl alcohol; and lignin sulfonate.

Examples of additives include a pore-forming agent, a lubricant, a plasticizer, a dispersant, and a solvent.

Examples of pore-forming agents include carbon materials such as graphite; resins such as polyethylene, polypropylene, and polymethyl methacrylate; plant materials such as starch, nut shells, walnut shells, and corn; ice; and dry ice.

Lubricants and plasticizers include alcohols such as glycerin; higher fatty acids such as caprylic acid, lauric acid, palmitic acid, arachidic acid, oleic acid and stearic acid; metal stearates such as Al stearate, polyoxyalkylene alkyl And ether (POAAE).

Examples of the dispersant include inorganic acids such as nitric acid, hydrochloric acid and sulfuric acid; organic acids such as oxalic acid, citric acid, acetic acid, malic acid and lactic acid; alcohols such as methanol, ethanol and propanol; ammonium polycarboxylate, poly Surfactants such as oxyalkylene alkyl ethers are listed.

As the solvent, for example, alcohols such as methanol, ethanol, butanol and propanol; glycols such as propylene glycol, polypropylene glycol and ethylene glycol; and water can be used.

(Honeycomb structure mask)
A mask 5 shown in FIG. 2 is used for sealing predetermined cells of the honeycomb structure 1 shown in FIG. The mask 5 is a circular plate-like member, and has a first through hole 5a and a second through hole 5b that penetrate in the thickness direction. In addition, the material of the mask 5 is not specifically limited, For example, a metal and resin are mentioned. Further, in order to facilitate positioning of the through hole 5a of the mask 5, an orientation flat 5c is formed on the mask 5, and the ring member 25 of the sealing device 100 shown in FIG. Corresponding protrusions 25b may be provided (see FIG. 6). The outer diameter of the mask 5 is preferably larger than the inner diameter of the recess 10 d of the main body 10 of the sealing device 100.

The first through holes 5a are for supplying the sealing material to the complete cells 1a of the honeycomb structure 1. The first through-hole 5a is provided in a portion that contacts the central portion (region other than the peripheral portion) of the end face of the honeycomb structure 1 when the mask 5 is used.

The cross-sectional shape of the first through hole 5a is a square corresponding to the cell 1a of the honeycomb structure 1 as shown in FIG. These first through-holes 5a are arranged in a staggered manner, and each first through-hole 5a is not adjacent to each other among the plurality of squarely arranged cells 1a in FIG. Are arranged to face only the plurality of cells 1a. The shape of the first through hole 5a is not limited to a square, but is smaller than the opening of the cell 1a and is similar to the shape from the viewpoint of the filling property of the paste-like sealing material. It is preferable.

The first through hole 5a is tapered as shown in FIG. 3, and the opening area differs depending on the position of the mask 5 in the thickness direction. That is, the opening area is continuously reduced from one surface F1 of the mask 5 to the other surface F2. The mask 5 is used in a state where the face F2 of the mask 5 is in contact with the end face of the honeycomb structure 1.

The first through hole 5a is not limited to the tapered shape shown in FIG. 3 as long as the opening area on the surface F2 is smaller than the opening area on the surface F1. For example, as shown in FIG. 4A, the first through hole 5a includes a tapered portion 6a whose opening area continuously decreases from the surface F1 toward the surface F2, and a surface F2 side of the tapered portion 6a. It may be constituted by a portion 6b which is located and has a constant opening area. Further, as shown in FIG. 4B, the first through hole 5a may have a step portion 6c whose opening area decreases discontinuously from the surface F1 toward the surface F2.

The taper angle in the first through hole 5a (angle α in FIGS. 3 and 4A) is 10 to 70 ° from the viewpoint of the rigidity of the mask 5 and the loss of the sealing material. The angle is preferably 30 to 60 °.

The first through hole 5a preferably has an opening area on the surface F2 of 0.03 mm ² or more and less than 90% of the opening area of the cell 1a to be sealed by the first through hole 5a. When the opening area on the surface F2 of the first through hole 5a is less than 0.03 mm ² , the sealing material is difficult to pass through the first through hole 5a, and it is difficult to supply a predetermined amount of the sealing material into the cell 1a. Become. The opening area of the first through-hole 5a is more preferably 0.05 mm ² or more, still more preferably 0.07 mm ² or more, it may be 0.2 mm ² or more.

On the other hand, if the opening area on the surface F2 of the first through hole 5a is 90% or more of the opening area of the cell 1a, the position of the first through hole 5a and the position of the opening of the cell 1a are slightly shifted. There is a possibility that the sealing material may be supplied to the neighboring cell 1a that should not be sealed. The opening area of the first through-hole 5a is preferably less than 80% and more preferably less than 60% of the opening area of the cell 1a.

The second through hole 5b is for supplying the sealing material to the incomplete cell 1b of the honeycomb structure 1. The second through-holes 5b are provided at a portion narrower than the cell pitch of the honeycomb structure 1 (length L in FIG. 1) at a portion that contacts the peripheral edge of the end face of the honeycomb structure 1 when the mask 5 is used. Preferably it is. The interval between the second through holes 5b is preferably L / 10 to 3L / 4, more preferably L / 5 to L / 2, from the viewpoint of reliably sealing all the cells 1b.

The shape of the second through-hole 5b may be any shape that can provide a large number of through-holes in a limited region regardless of the shape of the incomplete cell 1b. The shape of the second through-hole 5b is For example, it may be circular or rectangular, but is preferably circular. As shown in FIG. 2A, the mask 5 is formed with an annular band composed of a number of second through holes 5b.

The second through hole 5b preferably has an opening area on the surface F2 of 0.03 mm ² or more and less than 60% of the opening area of the cell 1a to be sealed by the first through hole 5a. When the opening area on the surface F2 of the second through-hole 5b is less than 0.03 mm ² , it becomes difficult for the sealing material to pass through the second through-hole 5b, and it is difficult to supply a predetermined amount of the sealing material into the cell 1b. Become. The opening area of the second through hole 5b is more preferably 0.04 mm ² or more, still more preferably 0.05 mm ² or more, it may be 0.2 mm ² or more.

On the other hand, if the opening area on the surface F2 of the second through hole 5b is 60% or more of the opening area of the complete cell 1a, the rigidity of the mask 5 tends to be insufficient, and the mask 5 is sealed with a slight shift. There is a possibility that the sealing material is supplied to the cell 1a in the vicinity which should not be, or the sealing material may easily leak to the outside of the outermost layer 1c shown in FIG. The opening area of the second through-hole 5b is preferably 50% or less, more preferably 40% or less of the opening area of the complete cell 1a.

The opening area of the second through-hole 5b may be constant over the entire range in the thickness direction of the mask 5, or, similarly to the first through-hole 5a shown in FIGS. It may be different depending on the position.

According to the mask 5, by reducing the opening area of the first through hole 5a on the surface F2 contacting the end face of the honeycomb structure 1, the position of the first through hole 5a and the position of the opening of the cell 1a are somewhat different. Even if it deviates, the sealing material can be supplied into the predetermined cell 1a through the first through hole 5a. In addition, the mask 5 has an advantage that it is easy to ensure sufficient rigidity as compared with the case where the entire opening area of the first through-hole 5a is increased. Further, by providing a large number of second through holes 5b in the mask 5, it is possible to more reliably seal the incomplete cell 1b.

(Sealing device)
A sealing device suitable for sealing the honeycomb structure 1 using the mask 5 will be described. A sealing device 100 shown in FIG. 5 mainly includes a main body unit 10, an elastic plate 20, a pump 50, and a holding unit 80.

The main body 10 is made of a rigid material. Examples of the rigid material include metals such as stainless steel and polymer materials such as fiber reinforced plastic. A recess 10 d is formed on the upper surface 10 a of the main body 10. In the present embodiment, the shape of the recess 10d is a columnar shape as shown in FIGS. The side surface 10b of the recess 10d is perpendicular to the upper surface 10a of the main body 10 and the bottom surface 10c is parallel. The diameter of the recess 10d can be set to 100 to 320 mm, for example. The depth of the recess 10d can be set to 0.2 to 20 mm, for example. The main body 10 is preferably provided with a vibrator 140 such as an ultrasonic vibrator.

The elastic plate 20 is disposed on the upper surface 10a of the main body 10 so as to cover the opening surface of the recess 10d. The elastic plate 20 has elasticity and can be easily deformed. As the elastic plate 20, a rubber plate is preferable. Examples of the rubber include natural rubber, and synthetic rubber such as styrene butadiene rubber, butadiene rubber, butyl rubber, ethylene propylene rubber, nitrile rubber, chloroprene rubber, fluorine rubber, silicone rubber, and urethane rubber. The thickness of the elastic plate 20 is not particularly limited, but can be, for example, 0.3 to 3.0 mm.

The elastic plate 20 is fixed to the main body 10 by a ring member 25 and a bolt 31. The ring member 25 has an opening 25a at a position corresponding to the concave portion 10d of the main body 10 and thereby has an annular shape. And the ring member 25 is arrange | positioned on the elastic board 20 so that the center part (opposite part with the recessed part 10d) in the elastic board 20 may be exposed. Accordingly, the peripheral portion of the elastic plate 20 is sandwiched between the main body portion 10 and the ring member 25. Through-holes h are formed in the ring member 25 and the elastic plate 20, and screw holes j corresponding to the through-holes h are formed in the main body portion 10, and bolts 31 pass through these through-holes h. The peripheral portion of the elastic plate 20 is fixed in close contact with the portion around the recess 10d on the upper surface 10a of the main body 10 by being screwed into the screw hole j and fixed.

As shown in FIGS. 5 and 6, the inner diameter of the opening 25 a of the ring member 25 is preferably larger than the inner diameter of the recess 10 d of the main body 10.

The main body 10 further has a communication passage 10e that opens to the bottom surface 10c of the recess 10d. In the present embodiment, the communication path 10e opens to the bottom surface 10c of the recess 10d, but may be open to the inner surface of the recess 10d. For example, the communication path 10e may open to the side surface 10b of the recess 10d. Further, the shape and number of openings of the communication passage 10e are not particularly limited.

A pump 50 is connected to the communication path 10e via a connection pipe 14.

The pump 50 includes a cylinder 51, a piston 53 disposed in the cylinder 51, and a piston rod 54 connected to the piston 53. A motor 55 that reciprocates the piston rod 54 in the axial direction is connected to the piston rod 54. The piston rod 54 may be moved manually.

In the present embodiment, a closed space V formed by the main body 10, the connection pipe 14, and the cylinder 51 is formed between the elastic plate 20 and the piston 53, and a fluid is contained in the closed space V. FL is filled. The fluid FL is not particularly limited, and may be a gas such as air, but is preferably a liquid, and particularly preferably spindle oil or the like. Then, by moving the piston 53, the fluid FL can be discharged from the recess 10d of the main body 10, and the fluid FL can be supplied into the recess 10d.

A holding unit 80 is provided on the main body unit 10. The holding unit 80 includes a holding tool 81 that holds the honeycomb structure 1 and a pneumatic cylinder 82 to which the holding tool 81 is connected.

The holder 81 holds the honeycomb structure 1 such that one end face faces the elastic plate 20 and the recess 10d as shown in FIG.

The pneumatic cylinder 82 has a cylinder 82a extending in the vertical direction and a piston 82b provided in the cylinder 82a. By adjusting the pressure supplied from the outside, the pressure on both the upper and lower sides of the piston 82b can be adjusted. It has become. As a result, the pneumatic cylinder 82 can move the holder 81 in the direction in which the honeycomb structure 1 and the elastic plate 20 approach each other and in the direction in which they move away from each other. Further, the pneumatic cylinder 82 can bring the honeycomb structure 1 into close contact with the mask 5 by pressing the holder 81 downward with a predetermined force according to the gas supply pressure before and after the piston 82b. Furthermore, the pneumatic cylinder 82 can also permit the holder 81 to move freely in the vertical direction by releasing the pressure before and after the piston. That is, the holding unit 80 can switch between a state in which the honeycomb structure 1 held by the holder 81 can freely move upward and a state in which the honeycomb structure 1 is fixed to the main body 10. .

(Housing method of honeycomb structure)
The sealing method according to the present embodiment is for sealing the opening of a predetermined cell of the honeycomb structure 1 using the mask 5. More specifically, this sealing method comprises the following steps:
(A) placing the mask 5 on one end face of the honeycomb structure 1 so that the face F2 of the mask 5 is in contact with the end face of the honeycomb structure 1; and (b) one end face of the honeycomb structure 1. Supplying a sealing material through the first through-hole 5a of the mask 5 to the opening of the cell to be sealed.

According to this sealing method, alignment with the end face of the honeycomb structure 5 can be easily performed, and a predetermined cell can be sealed more reliably than in the past.

The honeycomb structure 1 has incomplete cells 1b at the periphery as shown in FIG. Therefore, in the step (b), the sealing material is supplied to the incomplete opening of the cell 1b through the second through hole 5b of the mask 5.

In order to fabricate the honeycomb filter structure, the cell sealing process is performed on one end face of the honeycomb structure 1, and then the same sealing process is performed on the other end face. That is, after the step (b),
(C) the step of disposing the surface F2 ′ of the mask 5 ′ on the other end face of the honeycomb structure 1; and (d) the mask 5 ′ at the opening of the cell to be sealed on the other end face of the honeycomb structure 1. Supplying a sealing material through the third through-hole 5a ';
Are carried out sequentially.

As shown in FIG. 7, the mask 5 ′ has third and fourth through holes 5 a ′ and 5 b ′ corresponding to the first and second through

holes

5 a and 5 b of the mask 5, respectively. Each of the through holes 5a ′ and 5b ′ penetrates from one surface F1 of the mask 5 ′ to the other surface F2. The mask 5 ′ has the same configuration as the mask 5 except that the arrangement of the through holes 5a ′ is a staggered arrangement opposite to the arrangement of the through holes 5a of the mask 5 (see FIGS. 3 and 4). In order to seal the incomplete cell 1b on the other end face of the honeycomb structure 1, in the step (d), the sealing material is inserted into the opening of the incomplete cell 1b through the fourth through hole 5b ′ of the mask 5 ′. Supply.

Hereinafter, a method for sealing the honeycomb structure 1 using the sealing device 100 and the mask 5 described above will be described. First, from the state of FIG. 5, the pneumatic cylinder 82 is driven in advance and pulled up above the holder 81 that holds the honeycomb structure 1, and the mask 5 is removed from the elastic plate 20. Next, by pulling the piston 53 of the pump 50 downward, the fluid FL is discharged downward from the recess 10 d of the main body 10. As a result, as shown in FIG. 8A, the elastic plate 20 is deformed and is brought into close contact with the side surface 10b and the bottom surface 10c of the concave portion 10d, whereby the concave portion 20d of the elastic plate 20 is formed.

Subsequently, as shown in FIG. 8B, the sealing material 130 is supplied into the recess 20 d of the elastic plate 20. As necessary, the surface of the sealing material 130 is flattened and defoamed by driving the vibrator 140.

The sealing material 130 is not particularly limited as long as it can close the ends of the

cells

1a and 1b of the honeycomb structure 1, but is preferably liquid. For example, as the sealing material, a slurry containing a ceramic material or a ceramic raw material, a binder, a lubricant, a pore former, and a solvent can be exemplified.

Examples of the ceramic material include the constituent materials of the above-described honeycomb structure and the raw materials thereof. The amount of the ceramic material used can be, for example, 50 to 85 parts by weight with respect to 100 parts by weight of the slurry.

Examples of the binder include celluloses such as methylcellulose, carboxymethylcellulose, hydroxyalkylmethylcellulose, and sodium carboxymethylcellulose; alcohols such as polyvinyl alcohol; and organic binders such as lignin sulfonate. The amount of binder used can be, for example, 0 to 30 parts by weight with respect to 100 parts by weight of the slurry.

Lubricants include alcohols such as glycerin; higher fatty acids such as caprylic acid, lauric acid, palmitic acid, arachidic acid, oleic acid and stearic acid; and stearic acid metal salts such as aluminum stearate. The amount of lubricant used can be, for example, 0.5 to 20 parts by weight with respect to 100 parts by weight of the slurry.

Examples of pore-forming agents include carbon materials such as graphite; resins such as polyethylene, polypropylene, and polymethyl methacrylate; plant materials such as starch, nut shells, walnut shells, and corn; ice; and dry ice. The amount of pore-forming agent used can be, for example, 0 to 20 parts by weight with respect to 100 parts by weight of the slurry.

As the solvent, for example, alcohols such as methanol, ethanol, butanol and propanol; glycols such as propylene glycol, polypropylene glycol and ethylene glycol; and water can be used. Of these, water is preferable, and ion-exchanged water is more preferably used from the viewpoint of few impurities. The amount of the solvent used can be, for example, 10 to 40 parts by weight with respect to 100 parts by weight of the slurry.

The amount of the sealing material used for sealing one end face of the honeycomb structure 1 can be, for example, 3 to 5000 mL.

Subsequently, as shown in FIG. 9A, the mask 5 is set on the elastic plate 20 so as to cover the recess 10 d of the main body 10. At this time, the mask 5 is arranged so that the surface F2 faces upward. Next, the holder 81 is moved downward by the pneumatic cylinder 82 to bring the honeycomb structure 1 into contact with the mask 5. As a result, some of the cells 1a of the honeycomb structure 1 communicate with the first through holes 5a of the mask 5, and all the incomplete cells 1b of the honeycomb structure 1 and the second through holes of the mask 5 are communicated. Communicate with 5b. Further, the holding member 81 is pressed downward by the pneumatic cylinder 82 to fix the honeycomb structure 1 to the mask 5 and the main body 10 (step (a)). Alternatively, the mask 5 may be arranged on the end face of the honeycomb structure 1 in advance so that the position of the cell 1 a to which the sealing material is to be introduced and the first through hole 5 a are aligned, and this may be attached to the sealing device 100.

Next, by moving the piston of the pump 50 upward, the fluid FL is supplied into the recess 10d, whereby the elastic plate 20 moves toward the mask 5 as shown in FIG. 9B. This step is performed until the elastic plate 20 comes into contact with the mask 5 and the deformation of the elastic plate 20 is eliminated, as shown in FIG.

Thereby, the sealing material 130 is supplied into some cells 1a and all the cells 1b of the honeycomb structure 1 through the through

holes

5a and 5b of the mask 5, thereby forming the sealing portion 1p (step (b)). ).

Subsequently, after the downward pressing of the honeycomb structure 1 by the pneumatic cylinder 82 is stopped so that the honeycomb structure 1 can freely move upward, the piston 53 is further raised, and the elastic plate 20 and the main body 10 Further, fluid FL is supplied. Thereby, as shown in FIG. 10B, the elastic plate 20 is deformed in a convex shape upward, and the mask 5 and the honeycomb structure 1 are moved upward. At this time, the peripheral portion of the elastic plate 20 deformed into a convex shape is separated from the mask 5, so that the mask 5 and the honeycomb structure 1 can be easily separated from the main body portion 10.

Subsequently, after removing the honeycomb structure 1 from the holder 81, the top and bottom are turned over, and the honeycomb structure 1 is again held by the holder 81. Next, the same operation is performed using the mask 5 ′ in which the mask 5 and the first through-hole 5a are arranged in a zigzag arrangement opposite to each other (steps (c) and (d)). As a result, as shown in FIG. 11A, the other ends of the remaining cells 1a and all the incomplete cells 1b are sealed with the sealing material to form the sealing portion 1p. Subsequently, the mask 5 ′ and the honeycomb structure 1 can be easily separated from the main body 10 and the elastic plate 20 by deforming the elastic plate 20 upward in the same manner as described above.

In this manner, the honeycomb filter structure can be manufactured by drying and firing the honeycomb structure 1 that has been sealed at both ends.

According to the sealing method using the mask 5 and the mask 5 ', among the many complete cells 1a, only the cells 1a to be sealed can be sealed more reliably, and all the incomplete cells 1b can be sealed more reliably. Can be sealed. Further, when the elastic plate 20 shown in FIGS. 10A and 11A is in contact with and pressed against the mask 5, the elastic plate 20 is the first as shown in FIG. Enters the through hole 5a. For this reason, the loss of the sealing material can be sufficiently reduced. Furthermore, according to the sealing device 100, the elastic plate can be deformed into a convex shape as shown in FIG. 10B and FIG. 11B, so that the honeycomb structure after the sealing material 130 is supplied 1 can be easily pulled away from the main body 10 and the elastic plate 20. Therefore, the production efficiency can be increased, and the sealed honeycomb structure can be manufactured at a low cost.

As mentioned above, although the suitable embodiment of the present invention was described in detail, the present invention is not limited to the above-mentioned embodiment. For example, in the above-described embodiment, the mask 5 having the first through-hole 5a and the second through-hole 5b is illustrated. However, when the incomplete cell 1b is not present in the honeycomb structure or the cell 1b is formed using the mask. When there is no need to seal, a mask having the first through hole 5a but not having the second through hole 5b may be used.

The shape and structure of the honeycomb structure 1 are not limited to the above. For example, the outer shape of the honeycomb structure 1 may not be a cylinder, and may be, for example, a rectangular column such as a quadrangular column or an elliptical column. Further, if the opening area of the cell is about 0.6 to 7.0 mm ² (more preferably about 0.8 to 6.0 mm ² ), the cross-sectional shape of the cell is not limited to a square. It may be a quadrangle, a substantially hexagon, a substantially octagon, a substantially circle, or a combination thereof. Furthermore, the arrangement of the cells may not be the square arrangement of the cells 1a, and may be, for example, a triangular arrangement or a hexagonal arrangement.

DESCRIPTION OF SYMBOLS 1 ... Honeycomb structure, 1a ... Complete cell, 1b ... Incomplete cell, 5, 5 '... Mask, 5a ... 1st through-hole, 5b ... 2nd through-hole, 5a' ... 3rd through-hole 5b '... 4th through-hole, 6a ... tapered portion, 6c ... stepped portion, F1 ... mask surface (one surface), F2 ... mask surface (other surface).

Claims

A mask used for sealing a cell of a honeycomb structure,
The mask has a plurality of first through holes penetrating from one surface of the mask to the other surface, and the opening area of the first through hole on the other surface is larger than the opening area of the first through hole on the one surface. Even a small mask.
2. The mask according to claim 1, wherein the first through-hole has a tapered portion whose opening area continuously decreases from the one surface toward the other surface.
2. The mask according to claim 1, wherein the first through hole has a step portion in which an opening area discontinuously decreases from the one surface toward the other surface.
The first through hole has an opening area of 0.03 mm 2 or more on the other surface and less than 90% of the opening area of the cells of the honeycomb structure to be sealed by the first through hole. Item 4. The mask according to any one of Items 1 to 3.
The mask according to claim 4, wherein the first through hole has an opening area on the other surface of 0.2 mm 2 or more.
Among the regions in contact with the end face of the honeycomb structure during use, the portion further in contact with the peripheral edge of the end face of the honeycomb structure further includes a plurality of second through holes penetrating in the thickness direction of the mask. ,
The second through holes are provided at an interval narrower than the cell pitch of the honeycomb structure, and the opening area on the other surface is 0.03 mm 2 or more and should be sealed by the first through holes. The mask according to any one of claims 1 to 5, wherein the mask is less than 60% of the open area of the cell.
The mask according to claim 6, wherein the second through hole has an opening area of 0.2 mm 2 or more on the other surface.
A method for sealing cells of a honeycomb structure,
(A) placing a mask on one end face of the honeycomb structure;
(B) supplying a sealing material through a first through hole of the mask to an opening of a cell to be sealed on the one end face of the honeycomb structure;
With
The mask has a plurality of first through holes penetrating from one side of the mask to the other side, and an opening area of the first through hole on the other side is the first through hole on the one side. Smaller than the opening area of the hole,
(A) A sealing method in which, in the step (a), the mask is arranged so that the other surface of the mask is in contact with the end surface of the honeycomb structure.
The mask has a plurality of second through-holes penetrating in the thickness direction of the mask in a portion of the region contacting the one end surface of the honeycomb structure and contacting the peripheral edge of the end surface of the honeycomb structure. Further comprising
The second through holes are provided at an interval narrower than the cell pitch of the honeycomb structure, the opening area is 0.03 mm 2 or more, and the opening area of the cells to be sealed by the first through holes Less than 60% of
The sealing method according to claim 8, wherein, in the step (b), a sealing material is supplied to the opening of the cell to be sealed at the peripheral edge portion of the honeycomb structure through the second through hole of the mask.
(C) disposing another mask on the other end face of the honeycomb structure;
(D) supplying a sealing material through a third through hole of the other mask to an opening of a cell to be sealed on the other end surface of the honeycomb structure;
Further comprising
The other mask has a plurality of the third through holes penetrating from one surface of the mask to the other surface, and an opening area of the third through hole on the other surface is the third surface on the one surface. Smaller than the opening area of the through-hole,
The sealing method according to claim 9, wherein in the step (a), the mask is arranged so that the other surface of the mask is in contact with an end surface of the honeycomb structure.
The other mask includes a plurality of fourth masks penetrating in the thickness direction of the mask in a portion of the region contacting the other end surface of the honeycomb structure that contacts the peripheral edge of the end surface of the honeycomb structure. Further having a through hole,
The fourth through holes are provided at an interval narrower than the cell pitch of the honeycomb structure, the opening area is 0.03 mm 2 or more, and the opening area of the cells to be sealed by the third through holes Less than 60% of
The sealing method according to claim 10, wherein in the step (d), a sealing material is supplied to the opening of the cell to be sealed at the peripheral edge of the end face of the honeycomb structure through the fourth through hole of the mask.