Abstract: A control device (10?) comprises a control unit (10?) with a control element for controlling a fluid flow and being rotatable about a first axis (13) between an open position and a closed position, and a separate motor-driven actuator unit (24), which is mechanically coupled to said control unit (10?) to rotate said control element about said first axis (13) in a controllable fashion, whereby said actuator unit (24) comprises a driving part (25) with a driving element (31) being rotatable about a second axis (26), to be mechanically coupled to said control element in a coupling position to rotate said control element about said first axis (13), and a control part (28) for driving said driving element (31) in a controllable fashion. Said driving element (31) is removably coupled to said control unit (10?) by means of a spur gearing (Hirth serration) (22, 29).

Abstract: A device for controlling an airflow in a ventilation duct, comprising a pivotable air flap, which prevents an airflow in the duct when in the closed position. A housing of an actuator for the air flap, which may pivot freely about the relevant longitudinal mid plane, is mounted in the inner duct wall. The air flap, symmetrically or approximately symmetrically curved about the longitudinal mid plane of the ventilation duct and supported under load in a stable position on the duct wall, is rigidly fixed to the driveshaft of the actuator, by an angled lever arm, with a separation, in the region of the apex line thereof. The air flap rests roughly centrally, permanently on the points of contact with the inner duct wall, which move with the position of the flap, in a self-centering manner and, in the closed position, contacts the inner duct wall along a sealed, endless peripheral sealing surface.

Abstract: The invention relates to a device (12), for controlling an airflow (A) in a ventilation duct (10), comprising a least one pivotable air flap (24), which prevents an airflow (A) in the duct (10) when in the closed position. A housing (32) of an actuator for the air flap (24), which may pivot freely about the relevant longitudinal mid plane (LM), is mounted in the inner duct wall (34) of constant cross-section. The elastic air flap (24), symmetrically or approximately symmetrically curved about the longitudinal mid plane (LM) of the ventilation duct (10) and supported under load in a stable position on the duct wall (34), is rigidly fixed to the driveshaft (18) of the actuator, by an angled lever arm (20), with a separation (a), in the region of the apex line (S) thereof.