Compression ratio varying system for internal-combustion engine

Abstract

Abstract PURPOSE:To reduce abrasion in a compression ratio varying system having sub- piston fitted in sub-cylinder communicating with combustion chamber, by providing a check valve in a path coupling between the hydraulic chamber in the rear of sub-piston and spill port, thereby shortening the stroke of sub-piston. CONSTITUTION:Sub-piston 9 is fitted slidably in sub-cylinder 7 formed to be communicated with combustion chamber 5 then the sub-piston 9 is advanced/ retreated by the pressure in the rear hydraulic chamber 10 to vary the compression ratio. Here, a stem 13 is projected from sub-piston 9 to the outside of sub- cylinder 7 and a spill port 17 to be opened/closed by a spill body 18 fitted slidably over the stem 13 is provided at the end of projection. Furthermore, a check valve 21 openable only in the direction from the hydraulic chamber 10 toward the spill port 17 is provided in the operating oil path 14 between the hydraulic chamber 10 and spill port 17.

Inventors

• 👤 Mitsuharu Nakahara
• 👤 中原　光治
• 👤 Tomio Ishida
• 👤 石田　富雄
• 👤 Tsuneo Ariumi
• 👤 有海　常夫
• 👤 Yoshitaka Yoshida
• 👤 吉田　吉孝

Bibliographic Details