Piston with a diametric reduction of a skirt portion greater on the thrust side, than that on the counter-thrust side

Abstract

The piston of this invention is so profiled that the diametric reduction of the shoulder portion of the skirt is greater on the thrust side than on the counter-thrust side and that the difference in diametric reduction between the thrust side and the counter-thrust side is maximum at around a position corresponding to the center of the piston pin. In the compression stroke, the piston moves up pressed against the cylinder liner wall on the counter-thrust side but the inclination angle of the piston at this time is small. Near the top dead center, the piston is rapidly pivoted and strikes against the cylinder liner wall on the thrust side. The point on the piston hitting the cylinder liner wall is at around a position equal in height to the center of the piston pin. This reduces the impact force of the piston and therefore the slap.

Dependencies are inferred from the claim text.