Abstract: Vacuum cleaner is provided with independently operating on/off switches on the handle and the motor housing. A vacuum cleaner comprises a motor housing (2), which accommodates a suction motor (10) and a control unit (12) for controlling the suction motor (10), a hose 4, which can be coupled to the motor housing (2) and has a handle 8, a command switch (14) on the handle (8), for supplying a first on/standby command signal to the control unit (12), and a main switch (16) on the motor housing (2) for supplying a second on/standby command signal to the control unit (12). The command switch (14) and the main switch (16) operate independently of one another. As a result, the suction motor (10) can be switched on and off both at the handle (8) and at the motor (2) regardless of the position of the main switch (16).

Abstract: A vacuum cleaner is provided which comprises a housing (100) provided with an electric motor (110) and with an electronic circuit (120) for controlling the electric motor (110), which housing (100) is constructed for the connection of a suction tube (200) with a remote control circuit (210) for controlling the electronic circuit (120), the electronic circuit (120) being adapted to control the electric motor (110) both in the presence and in the absence of the suction tube (200).

Abstract: An apparatus, for example a vacuum cleaner, is provided which comprises an electric motor with variable motor power, a control circuit for controlling the variable motor power, and a vacuum chamber for generating a partial vacuum by means of the electric motor and, the control circuit being effective to temporarily increase the variable motor power to a power level above a nominal motor power in dependence upon the partial vacuum generated in the vacuum chamber.

Abstract: A circuit arrangement for deriving a direct voltage from an alternating voltage, particularly the mains alternating voltage. The circuit arrangement includes a switching transistor (T1) whose main current path is connected via a rectifier diode (D1) between the input and the output and whose control electrode is controlled by a thyristor (Th). The gate electrode of the thyristor is connected via a diac (D3) to a time-determining circuit comprising a series arrangement of a resistor (R1) and a capacitor (C1). A diode (D2) is arranged across the capacitor in such a way that the diode (D2) conducts during the periods when the rectifier diode (D1) is blocked.

Abstract: A circuit for controlling an AC current through a load. The load, e.g. a motor (3), is connected in series with a first triac (7) between two terminals (1, 2) adapted for connection to an AC supply voltage. A series circuit of a capacitor (6) and a parallel circuit consisting of a first (14) and a second (5) resistor is connected parallel to the first triac. The control electrode of the first triac is connected to the capacitor by means of a series circuit of a third resistor (9) and a second triac (10). A control electrode of the second triac is connected to the capacitor by means of a diac (8).