| 摘要 |
<p>1,180,256. Protective arrangements. K. DIEHL. 16 Nov., 1967 [23 Nov., 1966], No. 52139/67. Heading H2K. [Also in Division G3] An overload disconnecting arrangement for an automatic voltage control circuit of the type having a series transistor 44 the base of which is connected through a resistor to the collector or a suitable auxiliary voltage, and the emitter being connected to a potential divider 46, 47 across which the stabilized output voltage is obtained, transistor 44 being controlled by a second transistor 15 the base of which is connected to a tapping on the potential divider and its emitter connected through a reference voltage source to the earthed terminal of the divider and its collector connected to the base of transistor 44, comprises a switching device which in the event of overloads is operated by a continuous signal generated in the circuit whereby the base of the transistor 44 is connected to a reference potential, and further means are provided which after the elimination of the overload and after transmission of an appropriate signal, by non automatic means, switch the device into an inoperative condition until such a time as the output voltage has been restored. The circuit may be adapted for disconnecting all of a plurality of related outputs of differing polarity U1, U2 wherein the bases of the transistors, e.g. 44, 54 are connected to a common reference potential, and all the outputs are disconnected substantially simultaneously. If the output U2 is overloaded a resistor 70 is shunted hence the base potential of a transistor 60 rises rendering this transistor conductive thus blocking transistor 44 and subsequently transistor 54. When the fault is eliminated a switch 67 is reversed hence charging a capacitor 66 rendering a transistor 61 conductive thus blocking transistor 60 and rendering transistors 44, 54 conductive. When capacitor 66 is fully charged transistor 61 is again blocked. If output U1 is overloaded the transistor 54 is immediately blocked rendering transistor 60 conductive and hence again blocking transistor 44. The arrangement may disconnect further outputs, e.g. (U3), Fig. 4 (not shown), in a similar manner. In this arrangement the capacitor 66 is replaced by an inductor (116). A fuse (39), Fig. 2 (not shown), may be included in the circuit. Transistor 44 may be controlled by further transistors (not shown) connected in cascade.</p> |
