Abstract: In heat-connections between metal and ceramic, martensite stainless steel or martensite heat-resistant steel which can be hardened by quenching in a gas or vacuum after having been heated beyond the quench hardening temperature thereof are used as metal. The heat connection is by brazing or shrinkage fit at 800.degree. C. or more. Stress strain caused by a difference in thermal expansion coefficient between the two can be reduced. Further, since the metal can be connected to the ceramic while hardening the metal, man-hours can be reduced markedly.

Abstract: In heat-connection between metal and ceramic, martensite stainless steel or martensite heat-resistant steel which can be hardened a gas or vacuum after having been heated beyond the quenching temperature thereof are used as metal. The heat connection is brazing or shrinkage fit at 800.degree. C. or more. Stress strain caused by a difference in thermal expansion coefficient between the two can be reduced. Further, since the metal can be connected to ceramic while hardening the metal, man-hour can be reduced markedly.

Abstract: A heat-resistant casing for an internal combustion engine comprises an outer wall member made of an aluminum alloy by casting and an inner wall member made of ceramic and embedded in the outer wall member at the time of casting of the outer wall member. A coolant jacket is formed in the outer wall member and is communicated with a source of cooling medium so that cooling medium circulates through the coolant jacket.

Abstract: A metal-ceramic heat-insulating structure having a metallic tubular member fitted with a hollow cylindrical sintered ceramic, the inner surface of which is to be exposed to elevated temperatures. The sintered ceramic is bound to the metallic tubular member by means of a ceramic powder compacted in a gap located between the two members.

Abstract: A sintered body assembly having an inner section and an outer section is formed from independent inner and outer compacts corresponding to the inner and outer sections, respectively. The inner and outer compacts are so shaped that a predetermined clearance is provided therebetween. The outer compact is larger in shrinkage percentage at the time of sintering than the inner compact such that the clearance is filled by the compacts at the time of sintering thereby allowing the compacts to be formed into a single sintered body or an integral unit.

Abstract: The invention relates to a cylinder head for an internal combustion engine in which each combustion chamber has a prechamber. A cast metal body of the cylinder head has recesses each of which provides a prechamber, and a hollow and, for example, bell-shaped member of a porous ceramics is cast-inserted in the inner surface defining each recess. Use is made of a ceramics low in thermal expansion coefficient and heat conductivity, such as aluminum titanate or cordierite, and the porosity of the ceramics is 5 to 50%. Because of its porousness the cast-inserted ceramics member is easily machine-finished. After that, for enhancement of strength and durability, the cast-inserted member of the porous ceramics is impregnated with an inorganic refractory material by using either a solution of, for example, sodium silicate or aluminum phosphate or an aqueous suspension of a ceramics powder, or a mixture of the solution and the suspension.

Abstract: An internal combustion engines comprises at least one exhaust valve made of ceramics per each engine cylinder and a pluarality of intake valves made of steel. The relation in number and valve head diameter between the intake and exhaust valves is designed so as to give Pe<Pi and De>Di where Pe is the number of exhaust valves per each engine cylinder, Pi is the number of intake valve per each engine cylinder, De is the valve head diameter of the exhaust valves and Di is the valve head diameter of the intake valve.

Abstract: A rocker arm comprises an arm section extending throughout the overall length thereof. The arm section is made of ceramics and adapted to engage a cam, valve stem and a lash adjuster.

Abstract: A ceramic valve supporting structure for use in an internal combustion engine comprising: a ceramic valve having an integral stem, an upper portion of which is provided with a circular groove therearound; a frusto-conical shaped cotter comprising a pair of semi-cylindrical pieces, each inner surface of which has a lock projection located within said groove when secured to an outer surface of said stem; an annular retainer secured to an outer surface of said cotter to support said valve through said cotter, said retainer having an inner surface tapered to engage the outer surface of said cotter by wedging action due to a spring force acting upon to said retainer to bring said cotter into tight engagement with said stem; and an elastic layer provided between an inner surface of said cotter and the outer surface of said stem to absorb stress when said cotter engages said stem.

Abstract: An adjustment mechanism for a ceramic rocker arm. The ceramic rocker arm is formed with a smooth bored opening through the adjustment end of the rocker arm. An externally threaded adjusting shaft is passed through the opening and an internally threaded locking member such as a locking nut is disposed on the shaft and engaged on the external threads. An internally threaded member is disposed to engage the external threads of the shaft and also engage the adjustment end of the rocker arm.

Abstract: A piston pin made of ceramics is journalled in piston bosses of a piston made of aluminium alloy. Intermediate members are installed in bearing bores to receive therein terminal end portions of the piston pin. The intermediate members are made of metal which is intermediate in thermal expansion coefficient between the aluminium alloy forming the piston and the ceramics forming the piston pin.

Abstract: A piston boss is formed with an oil inlet hole for collecting oil flowing downward along a piston and allowing it to flow toward a snap ring and an end of a ceramic piston pin in contact with the snap ring. The oil having lubricated the snap ring and the end of the piston pin is collected by an oil outlet hole formed in the piston boss and allowed to flow downward therethrough.

Abstract: In a turbine rotor composed of a ceramic turbine blade and a metal shaft with an end to be machined, martensite stainless steel or martensite heat-resistant steel which can be hardened in a gas or vacuum after having been heated beyond the quenching temperature thereof is used as the metal. The ceramic blade and the metal shaft are heat-connected by brazing or shrinkage fit at 800.degree. C., or more. The metal shaft hardened through the heat-connection is tempered only at the end to be machined or the metal shaft heated to the quenching temperature is quench hardened only in part other than the end to be machined, thus facilitating the machining of the metal shaft locally which keeping the remaining part thereof in a quench hardened condition.

Abstract: In order to remove particulate matter from the exhaust gases which flow into the turbine impeller scroll of a internal combustion engine turbocharger, a separator which settles or centrifugally separates the solids from the gases is disposed between the engine manifold and the turbocharger. The separator is arranged to communicate with the turbocharger waste gate so that collected particulate matter is carried out of the device when the valve is opened to vent excessive back pressure.

Abstract: An auxiliary combustion chamber for an internal combustion engine having a semi-spherical insulating ceramic liner and a heat resistant ceramic nozzle portion. The chamber has an outer metal member that is cast around the ceramic liner to impart significant compressive stress thereto. The metal member extends past the ceramic liner to form a cylindrical portion. The ceramic nozzle portion is affixed in this cylindrical portion by a shrinkage-fit.

Abstract: A turbocharging system for an internal combustion engine improves performance and efficiency under low-speed, high-load operating conditions by adding secondary air to the exhaust gas upstream of the turbocharger. The secondary air combusts with unburned fuel contained in the exhaust gas to increase the temperature and pressure of the exhaust gas driving the turbocharger. Secondary air is added only when the exhaust gas temperature is above a prescribed temperature and the air-fuel ratio of the exhaust gas is below a prescribed ratio.

Abstract: A precombustion chamber provided with an arrangement for thermally insulating a cylinder head of an internal combustion engine from a combustion gas in the precombustion chamber comprising: (a) a hollow ceramic body which provides a precombustion chamber and is disposed within the hollow space for the precombustion chamber; (b) a hollow fitting member disposed surrounding the hollow ceramic body within the hollow space for mitigating and absorbing the stress produced between the cylinder head and the hollow ceramic body; and (c) seal means for sealing a space between the hollow ceramic body and the fitting member to provide a closed space therebetween, wherein said hollow fitting member is tightly secured to the hollow ceramic body through the seal means.

Abstract: A turbine having an improved connection between a ceramic rotor and a metal turbine shaft. The juncture between the rotor and the turbine shaft is disposed between a bearing supporting the turbine shaft and a sealing ring isolating the rotor from the oil reservoir of the turbine. A groove is formed at the juncture. Oil is allowed to circulate around the groove at the juncture between the rotor and the shaft, thereby providing a lowered temperature of the juncture, and hence preventing separation between the rotor and shaft due to differences in coefficients of thermal expansion.

Abstract: A process for producing high density sintered product which comprises molding a composite of an inorganic powder and an organic resin, burning off the organic resin, coating the surface of the molding with a rubber film, pressing said moldings under 2 ton/cm.sup.2 or more of isostatic pressure, and sintering.