Abstract: Piston for combustion engines consisting of an upper part forming the piston crown and a lower part forming the piston body. These two piston parts abut via annular contact surfaces in the piston axial direction and are coupled together via a gudgeon pin or a gudgeon pin bushing. In order to arrange such an unscrewed piston in such manner that its upper part need not be constructed to be rigid and heavy as in an articulated piston with pendulum shaft and that the construction of cooling channels between the upper and lower parts is possible without excessive expenditure and the constructional height of the piston can be small, the contact surfaces are mutually prestressed in the direction of the piston axis in that the gudgeon pin bore in the one piston part is arranged to be offset relative to the gudgeon pin bore in the other piston part in the unstressed condition in the direction of the piston axis. In this connection, the offset can amount to 0.5 to 10 parts per thousand of the piston diameter.

Abstract: Light-metal piston for combustion engines, having a sleeve-like insert embedded therein and controlling its heat expansion and being formed of a metal of smaller heat expansion coefficient than the piston base material. The insert is arranged in the solid material of the piston crown and extends around the entire piston periphery. Behind the insert, the piston base material is self-contracted to form a gap delimited by the insert on one side. On at least one edge or one side, the insert is not covered by piston base material, i.e. it extends up to the piston surface, this occurring however only in certain segments and not along the entire piston periphery. In the other segments, the insert lies beneath the piston surface and is thus covered by piston base material. To the extent that the insert is exposed on the piston end face, it is provided with an edge zone covering the depth of the self-contraction gap.

Abstract: The invention concerns components for internal combustion engines with heat resistant combustion chamber inserts, especially components made of light metal with casted porous ceramic inserts positioned by casting around the basic material, in which in order to lower the gas pressure which builds up under said inserts (3), at least one gas pressure release bore hole (4,5) is provided in the basic material of the component (1) which leads to the bottom of said insert. The invention further describes a process for the production of these components in which the insert is first fixed in its position relative to the basic element and thereafter the bore holes are produced in the basic material.

Abstract: A casting core for the creation of difficultly accessible cavities in castings of aluminum or of one of its alloys, produced from a water-soluble salt as base substance and burnt sugar as binding agent, and a process for the production of such a casting core wherein the base substance is mixed with burnt sugar in aqueous or organic solution, pressed in molds, and baked at elevated temperature.

Abstract: An internal combustion engine piston is fitted with bushes between its piston pin and the cross bore in the piston. The diameters of the piston pin and the piston cross bore are dimensioned independently of each other to meet the requirements imposed upon them, which allows the piston pin to be dimensioned only to such size as is required to withstand the bending stress imposed by the connecting rod, thus permitting the size of the piston pin and the reciprocating mass to be reduced in relation to conventional practice.

Abstract: In a machine housing with a relatively thin-walled structural member which at least partially encloses a space containing at least a small quantity of liquid and in which vibrations are produced mechanically, pneumatically and/or hydraulically, at least one element is provided between facing wall portions of the member and/or between a wall portion of the member and a facing wall portion of an adjacent part of the housing for preventing the occurrence of unacceptably loud noise resulting from the vibrations, the element extending between the wall portions while leaving open a gap accessible to the liquid.

Abstract: A piston incorporating a thermal barrier is produced by first making an annular piston ring carrier insert from steel. The insert comprises an annular body to the upper and lower radially-inner edges of which are secured the upper and lower edges of an annular element which is channel shaped in radial cross-section and the channel in which faces radially outward. The element is soldered or welded to the insert body so that an enclosed annular space is defined between the element and body. The insert thus formed is then heated in molten aluminium to "alfinize" its external surface. The treated insert is subsequently placed in a piston mold and the piston is molded about it from aluminium.