Abstract: An electromagnetic frictionally engaged clutch for arranging inside a drive train connecting a drive motor and a vehicle door or flap. The arrangement ensures that the vehicle door is securely held in each intermediate position, when the clutch is in an idle state, while maintaining the possibility of a manual emergency actuation of the vehicle door. The rotor includes at least one permanent magnet in addition to the electric coil, such that when a current does not pass through the coil, the armature disk is pressed against the friction lining of the rotor, with a force which is strong enough for the vehicle door or vehicle flap to securely remain in position occupied when the clutch is an idle state, and for the friction engagement between the armature disk and the friction lining to be overcome when the vehicle door or vehicle flap is subsequently manually actuated.

Abstract: A position indicator contains a resonant circuit. A first resistor having a minimum resistance, a second resistor having a maximum resistance, and a variable resistor whose resistance varies within the range of minimum to maximum resistances are connected to the resonant circuit at first, second, and third specific times based on predetermined timing information supplied from a tablet. Signal levels detected by the tablet at the first and second specific times are used as a lower limit and an upper limit of an operation quantity. Within this range, a signal level detected at the third specific time is converted into an operation quantity. Thus, the continuous quantity can be detected at a fast sampling rate without being influenced by the height and tilt of the position indicator.