Abstract: Disclosed herein is an internal combustion engine piston comprising a piston cap formed from a plurality of ceramic pieces, and a metal piston body, the piston cap being fixed to the top portion of the metal piston body, wherein the piston cap is made of one or more types of ceramic materials, and the ceramic pieces constituting the ceramic cap and the metal piston body are bonded together through a metallized layer coated onto the ceramic pieces and a metal-plated layer coated onto the metallized layer in such a manner that the bonding area between the ceramic piece or pieces and the metal piston body may be larger at a top central portion of the metal piston body than that between the ceramic piece or pieces and the metal piston body at another portion thereof. Also disclosed is a method of producing the same.

Abstract: This invention discloses a thermally insulated piston having a cap portion and a body portion. The cap can be made of metal or ceramic. The cap and body portion are joined together by a brazing alloy. The cap portion can have a groove for receiving the brazing alloy. The ceramic cap can have a retaining band portion in a retaining band groove the band being bonded to the body portion by a brazing alloy. The piston with the ceramic cap can have an interlayer between the cap and body portion, the interlayer being bonded to the cap portion and body portion by a brazing alloy. The interlayer can have an outer knife edge. The body portion has a machined groove adjacent to the cap portion comprised of cells filled with thermal insulating material.

Abstract: A heat insulated reciprocating component, such as a piston or a valve, for an internal combustion engine comprises a main component body and a ceramic member secured to the body by interference fit with a metal connector which is brazed to the body. In one embodiment, the main body of a piston has an outwardly opening cavity, a ceramic member in the cavity having an annular groove, and a ring seated in the groove and brazed to side of the cavity. In another embodiment, the combustion wall defining face of the valve has a ceramic member mounted thereon, and metal ring in overlapping engagement with the periphery of the member and brazed to the body of the valve. The invention also comprehends the method of making such a component by applying a metal ring in overlapping engagement with the periphery of a ceramic member, mounting a brazing alloy shim on the ring, assembling these parts on the combustion chamber end of the component, and brazing the ring to the component.

Abstract: In a cooled composite piston having a cooling passage adjacent to the interface and a method of making same, the upper part consists of forged steel and is formed on its underside with ribs bearing on mating surfaces of the lower part. To improve the resistance to thermal and mechanical stresses, the upper part has been welded by means of charge carrier rays to the lower part, which consists of cast ferrous material.

Abstract: An arc welding process is used for form wear-resistant surfaces at least in the uppermost ring groove of aluminum alloy pistons for internal combustion engines. To reduce the manufacturing costs and to avoid an increase of the weight of the piston, the piston blank is formed by machining with a groove in at least one region to be provided with a ring groove having wear-resistant surfaces. During a rotation of the piston blank about its longitudinal axis said groove is entirely filled by arc welding with a filler material which comprises a silicon-containing aluminum alloy. The molten pool is solidified as quickly as possible by an adequate cooling. The ring groove is subsequently formed by machining.

Abstract: A piston for an internal combustion engine is provided with a crown portion heat insulated from the remainder of the piston over all or substantially all of the area of the crown, to reduce the transfer of heat from the crown to the remainder of the piston. The insulation may be by a chamber extending across the piston and the chamber may contain a vacuum. Such a piston can be manufactured by a process involving roll-bonding aluminum or an aluminum alloy to a ferrous material in order to secure a crown of ferrous material to the remainder of the piston made from aluminum or aluminum alloy.

Abstract: This invention discloses a thermally insulated piston having a cap portion and a body portion. The cap can be made of metal or ceramic. The cap and body portion are joined together by a brazing alloy. The cap portion can have a groove for receiving the brazing alloy. The ceramic cap can have a retaining band portion in a retaining band groove the band being bonded to the body portion by a brazing alloy. The piston with the ceramic cap can have an interlayer between the cap and body portion, the interlayer being bonded to the cap portion and body portion by a brazing alloy. The interlayer can have an outer knife edge. The body portion has a machined groove adjacent to the cap portion comprised of cells filled with thermal insulating material.

Abstract: A method is disclosed of modifying a conventional internal combustion engine to accept ceramic material. A cast iron extension mamber is metallurgically joined to the cast iron engine block, the extension member having a wall defining a bore opening aligned with and larger than the bore opening of the engine block. The extension member has a height substantially equal to or greater than the axial stroke of the piston. The diameter of the upper portion of the wall, defining the bore opening in the engine block, is enlarged to define an annular shoulder; the shoulder has an outer surface substantially axially aligned with the wall defining the bore opening in the extension member. A cylindrical ceramic liner, such as zirconia or alumina, is attached within the wall of the bore opening of the extension member by use of a high strength metallic sleeve which is fitted along the outer surface of the shoulder. The ceramic liner has an internal surface aligned with the wall of the bore opening in the engine block.

Abstract: A piston is provided for an internal combustion engine, having a crown portion comprising an upper part and a lower or ring-bearing part which two parts are of different metals welded together. The two metals are chosen to have the same coefficient of expansion but the metal of the upper part of the piston crown is less heat-conductive while that of the ring-bearing part is highly heat-conductive. The piston has a cooling chamber formed in it, part of which chamber is adjacent the upper part of the piston crown while another part of the cooling chamber is adjacent the ring-bearing part.

Abstract: The invention relates to a piston assembly for compressor and the method of making the assembly. A piston body is molded with spaced apart downwardly open grooves formed with concave semicylindrically shaped summits and parallel side walls. The summits and sidewalls are formed with pimples. A connecting rod pin having a connecting rod attached thereto is press fitted into the grooves. The pimples may serve as weld pimples by being softened by a welding current. The pimples on the sidewalls may alternatively be mechanically swaged to press inwardly against the rod to hold it in its installed position.