| 摘要 |
906,677. Automatic control systems. BENDIX CORPORATION. Feb. 1, 1961 [Feb. 12, 1960 (2)], No. 3837/61. Class 38 (4). In an electric retroactive control system for a variable, the control signal may be nullified at will, to render the control system inoperative, by initiating feedback of signal pulses through a transfluxor storage device. In Fig. 1 an alternating voltage signal E 1 in an aircraft automatic pilot is applied through an amplifier 4 to control a servomotor - operated control surface (not shown). This signal is also applied through an amplifier 10, demodulator 11 and lag network 12 to a diode gating circuit 13 which is normally blocked. When, however, it is desired to control manually, pulse inputs P 1 are applied through rectifiers 132, 134 so that gating circuit 13 produces output pulses E 5 , the polarity and magnitude of which are dependent on the phase and amplitude of signal voltage E 1 . These output pulses, after amplification by a transistor 14, are applied to the control winding W 0 of a transfluxor 15 to produce a corresponding coupling between an A.C. energized winding W 1 and an output winding W 2 . The signal from the transfluxor is rectified at 20, re-modulated at 21 and fed, back to cancel the automatic control signal E 1 a switch 22 being closed during manual control. When automatic control is restored by opening switch 22 and ceasing to apply pulses to gate 13, the signal from transfluxor 15 remains at the value it had at the time of changeover to ensure a smooth change back to manual control if switch 22 is re-closed at any time. In one modification transfluxor winding W 0 is energized through a push-pull transistor amplifier and the energization of winding W 1 is pulsed to occur during the intervals between the energizations of winding W 0 to avoid interference effects. In another modification correct timing of applied pulses relative to the phase of the signal voltage E 1 permits demodulator 11 to be dispensed with. Specifications 662,860, 778,162, 858,208 and 848,209 are referred to. |
