Ngk Insulators, Inc.

Honda Giken Kogyo Kabushiki Kaisha

Koichi Ikeshima

Yukihito Ichikawa

Osamu Horikawa

Eiji Ito

Takashi Harada

Kazuhiko Kumazawa

Minoru Machida

Satoru Inoue

Isao Hattori

Masaru Kojima

Shigeru Mochida

Shinichi Tosa

Reiji Matsubara

Tomomi Sugiyama

Masayasu Ishikawa

Jun Kitagawa

Masayoshi Miwa

An assembling method for an assembly is provided: the assembly comprising a cell structure () housed and held in a metal vessel () via a compressible material having a cushioning property () by arranging it between outer periphery of the structure () and the vessel () in a compressed state with applying a mounting pressure to the structure () via the material () to hold the structure () in the vessel (). Information regarding outside dimension of the structure () and/or inside dimension of the vessel () being marked on their surfaces prior to the start of assembly, and the information is read, and a cell structure () and a metal vessel () are selected based on read information in assembly to achieve a proper holding condition therebetween. Regardless of variations in external dimension of the structure, etc. constituting the assembly, the minimization thereof, and proper holding state may be achieved easily without causing a fracture of the structure, etc.

Assembling method using marked information and assembly assembled by said assembling method

The present invention provides a ceramic honeycomb structure, capable of certainly repairing the defect parts formed in the outer walls without lowering the mechanical strength or the thermal shock resistance and solving the liquid leakage trouble to the outer walls in the catalyst coating process. The ceramic honeycomb structure comprises a number of passages divided by a number of partition walls, and an outer wall dividing the passages from an outside of the honeycomb structure. A ceramic material is filled into at least one defective area on a surface of the outer wall, which has a hole of at least 0.1 mm in width communicating with the passage and the outside.

Ceramic honeycomb structure

A thin-walled honeycomb structure includes: a circumferential wall, numerous partition walls disposed inside the circumferential wall, and numerous cell passages defined by the partition walls. A circumferential portion of the honeycomb structure is reinforced wholly or in a part within a certain distance from an extremity surface of the honeycomb structure by a reinforcing material that dissipates or evaporates at a high temperature, and a method for producing the same.

Thin-walled honeycomb structure and method for reinforcing the same

A method for assembling a cell structure in a metal vessel, including reading information as indicia located on a surface of a compressible material having a cushioning property, the information regarding the thickness and/or bulk density of the compressible material; selecting a cell structure, a metal vessel, and a compressible material which, when assembled as a cell structure housed in a metal vessel, have a proper holding condition based on the read information; assembling the selected cell structure in the selected metal vessel via the selected compressible material, the compressible material being located in a compressed state between an outer periphery of the cell structure and the metal vessel to hold the selected cell structure in the selected metal vessel.

Assembly method using marked information and assembly assembled by said assembling method

In a ceramic honeycomb structural body having a plurality of open-ended cells defined by cell walls, a reinforcing portion is formed in each corner part of an open-ended cell existing in a second zone outside a first zone inclusive of a center on a plane perpendicular to the open-ended cells.

Ceramic honeycomb structural body

A ceramic honeycomb structural body comprises a plurality of open-ended cells defined by an outer peripheral wall and many cell walls, wherein cell walls constituting the irregular open-ended cells located near to the outer peripheral wall have a thickness thicker than those of the other remaining cell walls.

A ceramic honeycomb catalyst having an excellent thermal shock resistance in which a carrier is coated on a ceramic honeycomb structural body, has a mean thermal expansion coefficient in a range from 40.degree. to 800.degree. C. of smaller than 0.7.times.10.sup.-6 /.degree.C. Therefore, it is possible to obtain a ceramic honeycomb catalyst having excellent thermal shock resistance in which a mechanical strength of a ceramic honeycomb structural body to which a carrier such as .gamma.-alumina is coated is not decreased and the carrier is not peeled off from the ceramic honeycomb structural body.

Ceramic honeycomb catalyst having excellent thermal shock resistance

In order to obtain a honeycomb structural body having excellent mechanical strength, which can eliminate a waste use of a catalyst, incomplete cells at an outermost peripheral portion of the honeycomb structural body are sealed selectively by ceramic materials. An incomplete cell does not have a square cross section if the complete cell has a square cross section, and is preferably defined by the cell having an area not more than 90% as that of the complete cell.

A honeycomb structure as a substrate for at least one catalyst includes a ridge arranged on at least one part of an outer surface of the honeycomb structure and extending in a direction of through-apertures thereof, and at least one notch formed in the at least one ridge. A method of producing the honeycomb structure includes the steps of extruding a ceramic batch to form a honeycomb structure having a ridge in the form of a shape extending at least one part of the honeycomb structure in cross-section, and removing at least at one part of the ridge in directions of through-apertures of the honeycomb structure to form a notch. With the arrangement of the honeycomb structure, it is possible to prevent any shifting of the honeycomb structure in directions of through-apertures of the structure and rotation of the structure about its axis relative to a converter can without closing any ends of through-apertures.

Method of producing a honeycomb structure

A ceramic honeycomb structural body for catalytic converters and filters for removing fine particles can be provided which is secured firmly in the catalytic converters with high reliability, minimum volume and small strength to external pressure without displacements and breakage thereof and a loss of expensive noble metals, by forming at least one step on the outer circumferential surface of the honeycomb structural body so as to form at least one recessed portion or protruded portion on the outer circumferential surface; the recessed portion or the protruded portion has a rough surface or is formed discontinuously to afford firm and safe holding of the ceramic honeycomb structural body in the vessel of the catalytic converter via a sealing member and/or a cushioning member.

Method of producing a honeycomb structural body having at least one step

A honeycomb structure as a substrate for a catalyst includes at least one ridge arranged on at least one part of an outer surface of the honeycomb structure and extending in a direction of through-apertures thereof, and at least one notch formed in the at least one ridge. A method of producing the honeycomb structure includes the steps of extruding a ceramic batch to form a honeycomb structure having a ridge in the form of a shape extending at least at one part of the honeycomb structure in cross-section, and removing at least one part of the ridge in directions of through-apertures of the honeycomb structure to form a notch. With the arrangement of the honeycomb structure, it is possible to prevent any shifting of the honeycomb structure in directions of through-apertures of the structure and rotation of the structure about its axis relative to a converter can without closing any ends of through-apertures.

Honeycomb structure

A ceramic honeycomb structural body for catalytic converters and filters for removing fine particles can be provided which is secured firmly in the catalytic converters with high reliability, minimum volume and small strength to external pressure without displacements and breakage thereof and a loss of expensive noble metals, by forming at least one step on the outer circumferential surface of the honeycomb structural body so as to form at lesat one recessed portion or protruded portion on the outer circumferential surface; the recessed portion or the protruded portion has a rough surface or is formed discontinuously to afford firm and safe holding of the ceramic honeycomb structural body in the vessel of the catalytic converter via a sealing member and/or a cushioning member.

Honeycomb structural body and method of producing the same

A honeycomb structure as a substrate for a catalyst has at least one partially melted surface on an outer surface of the structure. A roughness of the melted surface is coarser than other surfaces. With the coarse surface, shifting of the honeycomb structure in through-aperture directions and rotation about its axis are prevented, thereby enhancing the reliability of a catalyst converter incorporating the honeycomb structure therein. A method of producing the honeycomb structure includes steps of, after extruding a ceramic batch into a honeycomb structure, drying the extruded honeycomb structure, attaching a chemical compound having a low melting point at a predetermined position onto an outer wall surface of the dried honeycomb structure, and firing the structure to melt at least a part of the outer wall surface, thereby obtaining the honeycomb structure having a melted portion whose roughness is coarser than the other surfaces of the outer wall.

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Okazaki, Japan

Koichi Ikeshima