Piston with specific land characteristics

US5113817A · kind A · utility

Assignee

• Mahle GmbH · DE

Inventors

• Peter Kemnitz · Leutenbach, DE
• Michael Ullrich · Heubach, DE
• Hanspeter Wieland · Ditzingen, DE

Key dates

• Filing date: May 1, 1991
• Grant date: May 19, 1992
• Expiry date: May 1, 2011

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y02T10/12
• WIPO field: Engines, pumps, turbines
• WIPO sector: Mechanical engineering

Abstract

A piston for an internal combustion engine with a separate head and skirt which are joined by a piston pin. The ring belt extends downward from head and terminates above the pin. The space between the lower edge of the ring belt and a section of the head defines a cooling oil ring space. A depression is formed in the head and is partly defined by the section. The second land has the largest diameter and exclusively guides the piston. The height of the second land is in the range of three to seven percent of the piston diameter. The diametrical second land clearance is 1.5% to 2.5%. The diametrical third land clearance is one percent of the piston diameter. The diametrical top land clearance is in the range of 1.5 mm to 2.0 mm.