Patent ID: 8267055

Claim:
A variable compression ratio engine comprising at least: a casing ( 1 ); a primary crankshaft ( 2 ) rotatably mounted on said casing ( 1 ) to rotate about a primary crankshaft rotation axis ( 3 ), said primary crankshaft ( 2 ) having a primary crankpin ( 4 ) at an eccentricity from said primary crankshaft rotation axis ( 3 ); a cylinder ( 5 ); a piston ( 6 ) slidably fitted into said cylinder ( 5 ); a primary connecting rod ( 7 ), said primary connecting rod having a small end ( 8 ) pivotally mounted on said piston ( 6 ) at a wrist pin ( 9 ), said primary connecting rod having a big end ( 10 ); a control frame ( 11 ) pivotally mounted on said casing ( 1 ) to pivot about said primary crankshaft rotation axis ( 3 ); a secondary crankshaft ( 12 ) rotatably mounted on said control frame ( 11 ) to rotate about a secondary crankshaft axis ( 13 ) of said control frame ( 11 ), said secondary crankshaft ( 12 ) comprising a secondary crankpin ( 14 ), the secondary crankpin ( 14 ) being at an eccentricity from said secondary crankshaft axis ( 13 ) substantially equal to the eccentricity of said primary crankpin ( 4 ) from said primary crankshaft rotation axis ( 3 ); a secondary connecting rod ( 15 ); an eccentric ring ( 16 ) having an inner cylindrical surface ( 17 ) and an eccentric, relative to said inner cylindrical surface ( 17 ), outer cylindrical surface ( 18 ), said eccentric ring ( 16 ) being secured at one end of said secondary connecting rod ( 15 ), said eccentric ring ( 16 ) being rotatably mounted on said primary crankpin ( 4 ) by said inner cylindrical surface ( 17 ), said eccentric ring ( 15 ) being rotatably mounted on said big end ( 10 ) of said primary connecting rod ( 7 ) by said outer cylindrical surface ( 18 ), the other end of said secondary connecting rod ( 15 ) being rotatably mounted on said secondary crankpin ( 14 ) of said secondary crankshaft ( 12 ), the rotation of the primary crankshaft causes the rotation of the secondary crankshaft at the same direction and with the same instant angular velocity, the angular displacement of the control frame about the primary crankshaft rotation axis controls the compression ratio.