Patent ID: 9086147
Filing Date: 2015-07-21
Classification: F02F,F16J

Abstract:
1. A piston for use in a cylinder of an internal combustion engine, the piston having a crown portion extending away from a top end of the piston, an oval barrelled skirt depending from the crown so as to define a bottom end of the piston and a contact zone on a thrust side of the barrelled skirt and a contact zone on an anti-thrust side of the barrelled skirt wherein: the contact zone on the thrust side has a longitudinal axis bounded on a first side by a column of spaced apart closed ended elongate pockets and bounded on a second side by a column of spaced apart closed ended elongate pockets, a central portion of the contact zone free of closed ended elongated pockets and extending a length of the columns of spaced apart closed ended elongate pockets; and the spaced apart closed ended elongate pockets in the column on the first side having longitudinal axes arranged at an acute angle θ with respect to the longitudinal axis of the contact zone on the thrust side, the spaced apart closed ended elongate pockets in the column on the second side having longitudinal axes arranged at the acute angle θ with respect to the longitudinal axis of the contact zone on the thrust side, the acute angle θ being less than 90 degrees and positive for the spaced apart closed ended elongate pockets in the column on the first side of spaced apart closed ended elongate pockets, the acute angle θ being negative for the spaced apart closed ended elongate pockets in the column on the second side.