Patent attributes
A safety drive unit (1) with a safety circuit (12) that resets a flap or a valve into a specified safety position for controlling a gas or liquid volumetric flow, in particular in the field of heating, ventilation, and monitoring systems. The safety drive unit (1) comprises an actuator (14) with a controllable electric motor (28), a capacitive energy storage unit (20), and energy converter (22) with a power module, and a power supply (18). During normal operation, the electric current in the power module of the energy converter (22) is converted to a lower voltage and stored in the capacitive energy storage unit. If the voltage drops below a predetermined value or if there is a power failure, the stored electrical charge is converted back to a higher voltage by the same power module, and the electric motor (28) is activated until the specified safety position is reached.
