Piston and cylinder for two-cycle engines

US4135479A · kind A · utility

Assignee

• Karl Schmidt GmbH

Inventors

• Johannes Reitz · Heppenheim, DE
• Erich Stark · Arnstein, DE
• Dieter Schneck · Möckmühl, DE

Key dates

• Filing date: Dec 16, 1976
• Grant date: Jan 23, 1979
• Expiry date: Dec 16, 1996

Classification

• Technology area (CPC F): Mechanical Engineering; Lighting; Heating
• CPC primary: F02B2075/025
• WIPO field: Engines, pumps, turbines
• WIPO sector: Mechanical engineering

Abstract

A piston and cylinder for two-cycle engines wherein the fuel-air mixture is precompressed in the crankcase and flows to the combustion chamber through transfer passages formed in the cylinder wall and under the control of the piston movement. The piston skirt is formed with windows or openings adjacent the end faces of the piston pin, the latter being mounted in piston pin bosses carried by bearing brackets depending from the piston head and, when the piston is at its lower dead center, the windows or openings register with the inlet openings of the transfer passages so that the precompressed fuel-air mixture then flows through the interior of the piston, the openings in the piston skirt and the transfer passages and into the combustion chamber itself which contains a depression volume. The windows or openings in the piston skirt have approximately the same size as the inlet openings of the transfer passages which register with the windows when the piston is at its lower dead center and the piston pin bosses have an aerodynamically favorable shape and are joined to the lower frame portions defining the windows and spaced apart as closely as possible whereas the depression volume of…