| 摘要 |
<p>In an apparatus having an automatic switch-on device for a parallel appliance, preferably in the form of a vacuum cleaner, which is switched on at the same time as a main appliance is put into operation, which may be, for example, an electric hand tool, a machine tool or the like, it is proposed to drive a (generalised phase) control circuit which is provided for the parallel appliance and is known per se by means of a current sensor designed as an annular core straight-through current transformer in such a way that the electric motor of the parallel appliance is switched on with a predetermined start delay (soft start). The annular core straight-through current transformer is designed here in such a way that, for generating clean ignition pulses for the triac of the parallel appliance, the primary winding is formed by the one winding of the electrical lead of the main appliance and is passed through the central opening of the annular core. The annular core straight-through current transformer is designed in such a way that it goes into saturation when a predetermined output variable threshold value is reached, so that even very high primary currents caused by the operation of the main appliance do not overload the (generalised phase) control circuit and, in particular, do not damage its triac. …<IMAGE>… </p> |
