Abstract: A servo drive for the set ring of a louver for a motor vehicle has a self-locking gear motor, the output shaft of which is coupled with a control crank. The end of the control crank turned away from the output shaft is connected by way of a link in a toggle-like manner with a positioning rod that is longer by a multiple of its length, of which the end turned away from the control crank is coupled with the set ring. A housing that protects the crank drive extends along the circumference of the set ring and is fastened on the radiator frame together with a servo drive housing.

Abstract: The louver for a motor vehicle radiator has radially arranged fins (4) mounted in a circular channel (2) of a radiator frame (3) so they can be swiveled around their longitudinal axis, which are linked in the area of their radial outer ends with a set ring (5) surrounding the channel (2) for the execution of a swiveling motion between an open and closed position of the louver. A servo drive (6) for the set ring (5) has a self-locking gear motor, the output shaft (10) of which is coupled with a control crank (11). The end of the control crank (119 [sic: (11)] turned away from the output shaft (10) is connected by way of a link (12) in a toggle-like manner with a positioning rod (13) that is longer by a multiple of its length, of which the end turned away from the control crank (11) is coupled with the set ring (5). Such a housing (18) that protects the crank drive (11, 13) extends along the circumference of the set ring (5) and is fastened on the radiator frame (3) together with a servo drive housing (9).