Compression ratio setting device for an internal-combustion engine

摘要

An internal-combustion engine includes a cylinder block; a plurality of cylinders arranged in line in the cylinder block; a piston accommodated for reciprocating motion in the respective cylinders; a crankshaft received in the cylinder block; a connecting rod coupling each piston with the crankshaft; and a plurality of eccentric rings surrounding and supporting the crankshaft. Each eccentric ring is rotatable about a common ring axis radially spaced from the crankshaft axis. Further, ring-supporting bearing housings are accommodated in the cylinder block for supporting the eccentric rings. A ring-turning assembly adjusts in unison the angular position of the eccentric rings to radially shift the crankshaft, whereby the upper dead center position of the pistons is altered for varying the compression ratio thereof. The ring-turning assembly includes a setting drive for exerting a force upon actuation thereof; ring-turning components connected to at least some of the eccentric rings; and a coupling element connecting the setting drive with the ring-turning components for transmitting the force exerted by the setting drive to the ring-turning components for rotating the eccentric rings.