Patent ID: 7284512
Filing Date: 2007-10-23
Classification: F02B,F02D

Abstract:
1. An internal combustion engine variable compression ratio system comprising: a piston inner connected to a connecting rod via a piston pin; a piston outer that, while being fitted around the outer periphery of the piston inner so that the piston outer can slide only in the in an axial direction and having an outer end face facing a combustion chamber, is capable of moving to a low compression ratio position (L) close to the piston inner, a high compression ratio position (H) close to the combustion chamber, and at least one medium compression ratio position (M) between the low compression ratio position (L) and the high compression ratio position (H); and at least two sets of raising means disposed in line in the axial direction between an upper face of the piston inner and a lower face of the piston outer opposed to the upper face of the piston inner, each set of raising means comprising a movable raising member, the movable raising members being individually capable of pivoting in a peripheral direction between a non-raised position (A) and a raised position (B) around the axis of the piston inner and outer, the piston outer being held at the low compression ratio position (L) when two of the movable raising members are pivoted to the non-raised position (A), the piston outer being held at the medium compression ratio position (M) when only one of the movable raising members is pivoted to the raised position (B), the piston outer being held at the high compression ratio position (H) when two of the movable raising members are pivoted to the raised position (B), and each of the raising means further comprising a member opposed to the respective movable raising member and capable of changing a position in abutment against the movable raising member in the axial direction of the piston inner and piston outer.