Actuating device for variable adjustment of compression ratio of internal combustion engine, particularly reciprocating piston-internal combustion engine, has servomotor, by which compression ratio is variably adjusted

The actuating device has a servomotor (10), by which the compression ratio is variably adjusted. An adjustable compression ratio is maintained under avoidance of energy receiving by the servo motor. The servo motor is formed as an electric motor. A short-circuit device (22) of the electric motor is provided, by which two poles (N,S) of a magnet assembly (18) of the electric motor are partially bridged for maintaining the adjusted compression ratio by the electric motor. The poles are arranged directly adjacent to each other. Die Erfindung betrifft eine Stelleinrichtung zum variablen Einstellen wenigstens eines Verdichtungsverhältnisses einer Verbrennungskraftmaschine, insbesondere einer Hubkolben-Verbrennungskraftmaschine, mit wenigstens einem Stellmotor (10), mittels welchem das Verdichtungsverhältnis variabel einstellbar ist, wobei mittels des Stellmotors (10) ein mittels diesem eingestelltes Verdichtungsverhältnis unter Vermeidung einer Energieaufnahme durch den Stellmotor zu halten ist.