Abstract: A lock with a bolt, which can be displaced by an actuating element between an opened position and a locked position, wherein a blocking piece, which blocks the actuating element in the locked position, is assigned to the actuating element, and wherein the blocking piece can be moved from the locked position into the opened position by a solenoid. In order to assure a dependable operation of such a lock, the blocking piece can be moved out of the opened position into the locked position by a manually operable actuating part. A switching element emits a switching signal when the blocking piece reaches the locking position, or makes a transition from the opened position into the locked position.

Abstract: For operating electric drives, in particular of two-pole and multi-pole asynchronous induction motors intended for driving devices having at least two significantly different operating speeds it is proposed to operate at least one two-pole or multi-pole multi-phase asynchronous induction motor from a single-phase mains supply (L, N) by rendering conductive each of a plurality of power semiconductors (Triac T1, T2, T3) being connected in series to one of the windings (W1, W2, W3) each, only during a half wave of the single-phase supply voltage, in a manner staggered in time relative to the other series-connected semiconductor switches, and successively relative to the latter (FIG. 1).

Abstract: In connection with an automatic starting feature for an auxiliary unit, preferably a vacuum cleaner, which is switched on simultaneously when a main unit, for example an electric hand tool, a machine tool, or the like, is started it is proposed to trigger a conventional (phase) control circuit provided for the auxiliary unit by means of a current sensor taking the form of a ring-core bushing transformer in a manner such that the electric motor of the auxiliary unit is switched on with a certain delay (smooth-starting feature). The ring-core bushing transformer is designed in such a manner that, for producing clear firing pulses for the triac of the auxiliary unit, the primary winding is formed by the one turn of the electric supply line of the main unit and passed through the central opening of the ring core.

Abstract: In an operating device for high-current loads, such as fan motors, or the like, connected to the electric system of mobile units, in particular motor vehicles, it is proposed each respective electric motor is connected to the electric system via an electronic control circuit controlling the pulse width of the pulse supply voltage supplied to the motor for the purpose of adjusting the motor to different power requirements, with nominal-value adjustment. An interference elimination circuit including a series coil and at least one capacitor of high capacitance is arranged between the electronic control system and the electric system of the mobile unit. The series coil is equipped with an iron-powder core and designed in such a manner that no saturation is obtained even under maximum current conditions so that a sufficiently high inductivity reserve remains available for pulse damping.