is connected in the manner of a hinge to segmented wheel 20 which is mounted in such a manner that it can rotate about axis a in housing 22 housing 22 can be connected in a fixed manner to the housing of the clutch or to a transmission housing segmented wheel 20 comprises on circumferential area toothing 24 which meshes with spiral threading 28 formed on output shaft 26 of electric motor 14 to detect turning of output shaft 26 increment counter 30 is provided electronic control device 32 with a microprocessor and associated storage devices serves to control electric motor 14 where one input is connected to increment counter 30 and additional inputs are connected in given cases via a bus to outputs of sensors or another control device where via these outputs control device 32 is supplied with data relevant to the operation of the clutch one output of control device 32 is connected to electric motor 14 the ability of segmented wheel 20 to turn is limited by at least one stop 34 which stop face 36 of the segmented wheel abuts at the end of the actuation path of actuating element 16 during the turning of segmented.