Ngk Insulators, Inc.

Minoru Machida

Toshio Yamada

Yukihito Ichikawa

Akinori Wakasa

Masaomi Kamiya

Yasuhiro Miyakawa

Toshihiko Hijikata

Yoshiyuki Kasai

Shigenori Ito

Koichi Ikeshima

Takayuki Ogasawara

Seiichi Asami

Masashi Yano

Takeshi Naito

Itsuo Kondo

Kazuyuki Mizoguchi

Hideki Hosokawa

Filter has a filter main body, a container, a first counter room, and a second counter room. A counter air is introduced into the first counter room through the counter air discharge valve, and fine particles trapped in the filter main body are removed and transported to the second counter room. Then, the removed fine particles are further transported to a process portion isolated from an exhaust gas passage, and the fine particles are fired in the process portion. Since the process portion is isolated from the exhaust gas passage, the fine particles in the process portion are not returned to the filter main body. Moreover, since the fine particles are transported by the counter air only to the second counter room, it is possible to reduce an amount of the counter air.

Method and apparatus for processing exhaust gas

A ceramic honeycomb catalytic converter having a novel canning structure capable of stably retaining a thin-walled ceramic honeycomb catalyst within a metal casing for a long period. A retainer member in the form of a ceramic fiber mat is disposed between an inner peripheral surface of the casing and an outer peripheral surface of the honeycomb catalyst, in a compressed state to generate a surface pressure for retaining the honeycomb catalyst in place. The ceramic fiber mat is composed of heat resistant and non-intumescent ceramic fibers, and has a compression characteristic which is substantially free from a significant increase or decrease over an operative temperature range of the catalytic converter. The casing may be provided with at least one locking member for locking the ceramic fiber mat in a flow direction of exhaust gas passed through the honeycomb catalyst.

Ceramic honeycomb catalytic converter

In a honeycomb catalytic converter having a metal case, a honeycomb catalyst mounted in the metal case, and a securing member used for mounting the honeycomb catalyst in the metal case and arranged between an outer surface of the honeycomb catalyst and an inner surface of the metal case, at lest one of an inlet portion and outlet portion of the honeycomb catalyst has a double cone structure in which an inner cylindrical member is arranged in the metal case. The honeycomb catalytic converter mentioned above can mount the honeycomb catalyst stably in the metal case for a long period of time even when exposed to high temperatures.

Honeycomb catalytic converter

An exhaust gas recirculation device for an internal combustion engine has a filter for trapping particulates in a recirculation gas, which is arranged in a recirculation gas route, and a device for generating a reverse air flow in which a pure gas flow for the reverse air flow passing through said filter in a reverse direction with respect to a recirculation gas flowing direction in the filter is generated. In the exhaust gas circulation device, the trapped gases are discharged out of the filter by the reverse air flow and are not returned into the internal combustion engine due to an engine exhaust pressure.

Exhaust gas recirculation device for internal combustion engine

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.

Ceramic honeycomb structural body

A ceramic honeycomb catalyst includes a thin-walled honeycomb structural body (10) and a catalytic substance carried by the honeycomb structural body (10). The honeycomb structural body (10) has a number of longitudinally extending flow passages (13) defined by an outer peripheral wall (11) and partition walls (12) with a reduced thickness (t). The honeycomb structural body (10) satisfies particular relationships between the partition wall thickness (t) and the open frontal area (OFA) or bulk density (G). Notwithstanding the thin-walled partition walls, the honeycomb structural body (10) has practically satisfactory compressive strength characteristics. The catalyst comprising the honeycomb structural body (10) has reduced pressure loss and heat capacity.

Ceramic honeycomb structural body and catalyst comprising the same

A curved honeycomb structural body having a number of through holes extending through the structural body along a direction in which the honeycomb structural body is curved. Thicknesses of interior walls defining through holes are set larger on a radially outer side of the curved portion than on a radially inner side thereof.

Curved honeycomb structural bodies

In an exhaust gas purifying apparatus including first and second exhaust converters composed of a honeycomb catalytic substrate, arranged in sequence from an exhaust manifold downstream along exhaust gas flow of an engine, wherein the catalytic substrate of the first converter has a heat capacity of not exceeding 0.5 J/K per 1 cm.sup.3 in temperatures ranging from room temperature up to 300.degree. C., and the catalytic substrate of the second converter has a geometric surface area of at least 25 cm.sup.2 /cm.sup.3. The first converter purifies exhaust gas immediately after starting up and before completion of warming up of the engine, and the second converter further purifies noxious contents still remaining as being beyond capacity of the first converter.

Exhaust gas purifying apparatus

A honeycomb structural body including an outermost peripheral wall, and partition walls axially defining a number of through holes inside the outermost peripheral wall. The honeycomb structural body is bent around at least one line located orthogonally to an extending direction of the through holes, wherein L1/L2.gtoreq.0.8, and R.gtoreq.100 mm, in which L1 is an axial length of a longest through hole among through holes located in an outer portion of the honeycomb structural body, L2 is an axial length of a shortest through hole among through holes located in an inner portion of the honeycomb structural body, and R is a radius of curvature of a center line of the honeycomb structural body defined by continuously connecting centroids of said outermost peripheral wall of the honeycomb structural body in respective planes orthogonal to the extending direction of the through holes thereof. The outer and inner portions of the honeycomb structural body are located outside and inside a plane, respectively, passing the center line of the honeycomb structural body and always extending in parallel to the at least one line around which the honeycomb structural body is bent.

Honeycomb stuctural bodies

A curved honeycomb structural body having a number of through holes penetrating along a direction in which the honeycomb structural body is curved. Pitches between adjacent interior partition walls defining through holes are set smaller on a radially outer side of a curved portion than on a radially inner side thereof.

A ceramic precombustion chamber construction for an internal combustion engine including a precombustion chamber formed by a ceramic body to be inserted in a precombustion chamber receiving cavity of a metal cylinder head. Projections are formed on an outer circumferential surface of a metal sleeve fitted on the ceramic body, or on an inner circumferential surface of the precombustion chamber receiving cavity of a metal cylinder head, or on an outer circumferential surface of the ceramic body. Thermal insulating spaces are formed by the projections and the inner circumferential surface of the precombustion chamber receiving cavity or the outer circumferential surface of the metal sleeve or the outer circumferential surface of the ceramic body. One of the projections is formed with a glow-plug receiving aperture which communicates with a glow-plug receiving aperture formed in the precombustion chamber receiving cavity of the metal cylinder head. As a result, leakage of burnt gases is prevented to ensure a complete thermal insulating effect.

Precombustion chamber construction for an internal combustion engine

A cylinder head has a ceramic precombustion chamber for an internal combustion engine. The cylinder head includes a part of the cylinder head made of a ceramic body having an injection aperture communicating with a main combustion chamber for jetting burning gases therethrough, a metal sleeve fitted on an outer circumference of the ceramic body and fitted in a precombustion chamber insert bore forming part of the cylinder head, and a head gasket interposed between the cylinder block forming the main combustion chamber and the ceramic body, the metal sleeve and the cylinder head. A surface of the ceramic body facing to the head gasket extends onto a side of the main combustion chamber beyond a surface of the ceramic body opening the injection aperture into the main combustion chamber.

Cylinder head with ceramic precombustion chamber

A precombustion chamber construction for an internal combustion engine comprises a precombustion chamber constructed by a ceramic body having a glow-plug receiving aperture to be inserted in a precombustion chamber receiving cavity of a metal cylinder head. A metal sleeve may be fitted on the ceramic body. A seat is formed at an entrance of a glow-plug receiving aperture on an outer circumferential surface of the metal sleeve, thereby preventing any leakage of burnt gases to ensure the complete thermal insulating effect. The metal sleeve is not necessarily needed. In this case, the seat is formed at an entrance of the glow-plug receiving aperture on an outer circumferential surface of the ceramic body.

Precombustion chamber construction for internal combustion engine

A ceramic precombustion chamber for an internal combustion engine such as a diesel engine consists of a metal ring and a ceramic body fitted in the metal ring by shrinkage fit. The ceramic body has a through-aperture for an injection nozzle and a combustion gas injection aperture. A shrinking allowance at a lower portion of the ceramic body with the metal ring is smaller than that an upper portion of the ceramic body with the metal ring, thereby decreasing surface pressures at the lower portion of the ceramic body to prevent cracks which would occur in the lower portion caused by surface pressures resulting from the shrinkage fit.

Ceramic precombustion chamber for internal combustion engine

A ceramic precombustion chamber construction of an internal combustion engine includes at least one ceramic body having a circular cross-section, a metal ring in which the ceramic body is fixed by shrinkage fitting, and at least one key interposed between the ceramic body and the metal ring for preventing rotation therebetween. Contour lines of a key receiving notch formed in an inner circumference of the metal ring are positioned on inner sides of contour lines of a key receiving notch formed in an outer circumference of the ceramic body. With the arrangement, the ceramic body is prevented from loosening from the fitting with the metal ring due to heat and vibration in use and is prevented from being damaged resulting from cracks occurring in the ceramic body.

Growing community of inventors

Nagoya, Japan

Minoru Machida