Piston of light metal

US4754731A · kind A · utility

Assignee

• Alcan Aluminiumwerk Nurnberg GmbH · DE

Inventors

• Gerhard Bohm · Stein, DE
• Helmut Zweck · Nuremberg, DE

Key dates

• Filing date: Jul 28, 1986
• Grant date: Jul 5, 1988
• Expiry date: Jul 28, 2006

Classification

• Technology area (CPC F): Mechanical Engineering; Lighting; Heating
• CPC primary: F05C2251/042
• WIPO field: Engines, pumps, turbines
• WIPO sector: Mechanical engineering

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.