GB662844A - Control system - Google Patents

Abstract

662,844. Automatic control systems. BENDIX AVIATION CORPORATION. Jan. 31, 1947 [Feb. 18, 1946], No. 3038/47. Class 38 (iv). An electrical control signal is produced by a normally balanced bridge which is rendered unbalanced by the change in temperature of a second bridge forming one of its arms and to which the initiating signal is applied. In a craft control system, as shown, Fig. 4, which is an improvement on that described in Specification 611,226, the deviation signal derived at 11 is applied through the amplifier 16 to the servomotor 42 of the control surface 10, and to stabilize the system at the correct datum, an additional signal is applied, with the feed-back signal, to the servomotor through the valve 82 and the time-delay, heat-responsive bridges respectively composed of equal resistors 68, 69, 70, 71 and 73, 74, 75, 76. The heat responsive bridges, together with the resistors 60, 61 form a further normally balanced bridge to which is applied the followup signal and which unbalances in a sense dependent on the sense of the follow-up signal if the follow-up signal is persistant, to provide the additional automatic trim control signal. In a further embodiment, Fig. 5 (not shown), heating is prevented in a control system as in Fig. 4 by the application of the deviation signal to the time-delay bridge circuit, the output of which is applied, with the deviation and follow-up signals to the servomotor. Specifications 662,831 and 662,845, [Group XXXVI], are referred to.