Denso Corporation

Toyota Jidosha Kabushiki Kaisha

Nippondenso Co., Ltd.

Mamoru Nishimura

Mikio Ishihara

Hiromi Sano

Makoto Saito

Masakazu Tanaka

Yasunao Miura

Keiji Ito

Yoshitsugu Ogura

Tosiharu Kondo

Seiji Okawara

Kojiro Tokuda

Hirofumi Yamashita

Takeshi Ueda

Hirohumi Yamashita

An exhaust gas purifying filter is made of a ceramic material in a honeycomb structure having introduction passages for introducing exhaust gas that includes particulate matter emitted from an internal combustion engine, porous walls that collect the particulate matter and exhaust passages for exhausting the exhaust gas after the particulate matter has been removed therefrom, with the porous walls supporting a catalyst for oxidizing and removing the particulate matter. The porosity of the porous wall is in a range from 55 to 80%, the mean pore size is in-a range from 30 to 50 &#x3bc;m, and the total volume X of the pores included in the exhaust gas purifying filter and the volume Y of the pores that are not smaller than 100 &#x3bc;m satisfy the relation of inequality Y/X&#x2266;0.05.

Method of manufacturing an exhaust gas purifying filter

A filter catalyst is for purifying exhaust gases emitted from internal combustion engines and including particulates, and includes a wall-flow honeycomb structure and an upstream-side straight honeycomb structure. The wall-flow honeycomb structure includes inlet cells clogged on the downstream side of the exhaust gases, outlet cells neighboring the inlet cells and clogged on the upstream side of the exhaust gases, filter cellular walls demarcating the inlet cells and the outlet cells and having pores, and a catalytic layer formed on the surface of the filter cellular walls and/or the surface of the pores of the filter cellular walls. The upstream-side straight honeycomb structure is disposed on the upstream side of the exhaust gases with respect to the wall-flow honeycomb structure, is provided integrally with the wall-flow honeycomb structure, and includes upstream-side straight cells in which the exhaust gases flow straight, and upstream-side cellular walls demarcating the upstream-side straight cells.

Filter catalyst for purifying exhaust gases

An exhaust gas purifying filter having a high strength and an excellent efficiency of exhaust gas purification and a method for manufacturing the same are provided. An exhaust gas purifying filtercomprises a ceramic honeycomb structurehaving a surrounding wall, partition wallsprovided in a honeycomb pattern within the surrounding wall, and a plurality of cellspartitioned by the partition wallsand penetrating through end faces. If a virtual lineis drawn on the end facesof the structureby continuously connecting points at a distance of 1.0 to 3.0 times the cell pitch in the direction toward the center from an inner surfaceof the surrounding wall, not less than 90% of a peripheral areaoutside the virtual lineis blocked with plug material

Exhaust gas purifying filter with reinforced peripheral area and method for manufacturing the same

A catalyst-loaded ceramic filter made of a ceramic material capable of directly supporting a catalyst component thereon is capable of providing early activation of the catalyst with a low coefficient of thermal expansion and light weight, without compromising the high porosity of the filter substrate. A catalyst-loaded ceramic filter is made of a ceramic material of which one or more kinds of element among its constituent elements is substituted with an element other than the constituent elements, for example a ceramic material with a part of Si or other elements included in cordierite is substituted with W or Co, as a filter substrate of honeycomb structure having a number of cells separated by porous walls, and supporting a catalyst such as a noble metal directly on the W.

Ceramic filter and catalyst-loaded ceramic filter

The present invention provides an exhaust gas purifying filter that has an increased contact area, between a catalyst supported on the dividing walls of a honeycomb structural body and particulate matter deposited thereon, and can improve the capacity of the catalyst to oxidize the particulate matter, and a method of manufacturing the same. According to the present invention, the exhaust gas purifying filtercomprising the honeycomb structural bodymade of ceramic and the catalystsupported on the surface of the dividing wallsof the honeycomb structural bodyhas void ratio, of the dividing wallof the honeycomb structural body, in a range from 55 to 80%, and the proportion of surface pores is 20% or higher.

Exhaust gas purifying filter and method of manufacturing the same

A ceramic material containing organic binder is formed by extrusion, dried and cut off so as to make the honeycomb bodyhaving the bulkheadsand a plurality of cellspartitioned by the bulkheadsand penetrating between both end faces of the honeycomb body. The tapered jighaving a tapered forward end portionis inserted into the openingof the cellof the honeycomb body. Then, the bulkheadsare heated and softened and deformed by a pushing force given by the tapered jigso that the openingof the cellis expanded to form the large opening, and the openingof the adjoining cellis reduced at the same time so as to form the small opening. After that, the honeycomb bodyis fired. In this way, the exhaust gas purifying filter for collecting particulates is manufactured.

Exhaust gas purifying filter and manufacturing method therefor

An exhaust purification filter having high filter efficiency and low pressure loss. The exhaust purification filter purifies exhaust gas by trapping particulate matter contained in exhaust gas discharged from an internal combustion engine. The exhaust gas purification filter has a honeycomb structure composed of partitions having a large number of pores, and cells separated by the partitions. The surface opening area of the partitions attributable to pores having a surface opening diameter of 10 &mgr;m or less is 20% or less of the total surface opening area ratio.

Exhaust gas purification filter

An exhaust gas purifying filter employs plugs that can be used as part of filter. The exhaust gas purifying filter has a honeycomb structure including a multitude of cells each surrounded by walls. Each of the cells is stopped with a plug on one end and the walls and the plugs are all made of a porous material. The value of M&equals;(L/t)&times;(P /P ) is in a range of 10<M<90, where P is the porosity of the walls, P is the porosity of plugs, t is mean thickness of the walls and L is mean length of the plugs.

Exhaust gas purifying filter

An exhaust gas filter is capable of suppressing the generation of an excessive pressure loss due to the particulates deposited. At least a part of a multiplicity of cells surrounded by partitioning walls of the honeycombed exhaust gas purification filter have plugs on one of their two end portions. At least a part of the cells to be arranged on the downstream side in the fluid path are partial plugs having openings allowing the fluid flow. The pressure loss caused when the fluid entering the cells passes through the partitioning walls is smaller than the pressure loss caused when the exhaust gas passes through the partial plugs.

A honeycomb structure comprising at least one main honeycomb structure and sub-honeycomb structures axially disposed, in series, on both end surfaces of the main honeycomb structure Partial plugs are constituted for some of the cells of the main honeycomb structure by facing the intersecting portions of partitioning walls surrounding the cells of the sub-honeycomb structure disposed adjacent to the main honeycomb structure with some of the cells of main honeycomb structure, and the arrangement of the partial plugs at one end surface of the main honeycomb structure differs from that at the other end surface of the main honeycomb structure

Honeycomb structure constituted by main and sub honeycomb structures

There is provided a honeycomb structural body with a high cell density of 600 cells/in or greater and excellent catalyst loading properties. In a honeycomb structural body comprising a plurality of cells formed by providing partition walls composed mainly of cordierite, which has the chemical composition SiO : 45-55 wt %, Al O : 33-42%, MgO: 12-18 wt %, in a honeycomb fashion, the density of the cells is at least 600 cells/in and the pore volume of the partition walls is at least 30%.

Honeycomb structural body

There is provided a ceramic honeycomb structure with excellent thermal shock resistance. The ceramic honeycomb structure ( ) comprises partitions ( ) arranged in a lattice forming a plurality of cells ( ) and an outer shell ( ) surrounding the perimeter of the partitions ( ), and the outer shell ( ) is provided with slits ( ) formed by cutting the outer shell ( ) in the lengthwise direction along its entire length.

Ceramic honeycomb structure

A method for cutting an extruding honeycomb structure by a jet of high pressure water. The jet is controlled in position to assure a smooth, straight cut perpendicular to the extruding direction.

Growing community of inventors

Nagoya, Japan

Mamoru Nishimura