Belt retractor system

The system has a frame (30), a rotatably mounted belt spool (32), a blocking mechanism for selective spool blocking, a vehicle sensitive sensor, an actuator for the blocking mechanism, an electric motor (10) for driving the spool, an electronic control unit with an input and an output interface. The sensor is connected to the input interface and the actuator and motor are connected to the output interface. Independent claims are also included for the following: an occupant restraining system for motor vehicles.