GB681878A - Positioning system monitor - Google Patents

Abstract

681,878. Automatic steering control systems. BENDIX AVIATION CORPORATION. Dec. 28, 1950 [Jan. 25, 1950], No. 31514/50. Class 38 (iv). In a system in which an A.C. servomotor positioning a member is controlled in accordance with a signal applied to a thermionic valve included in an amplifier and phase discriminator network which controls the servomotor through a balanced circuit, the balanced circuit is normally connected to an A.C. source but is automatically disconnected therefrom to discontinue operation of the servomotor upon loss of a voltage supply for the thermionic valve. As applied to an aircraft automatic pilot, rudder 10 is controlled by a two-phase servomotor 20, the energization of one phase 19 of which is controlled by signals from a stabilized earth inductor compass, a rate-of-turn device 13, and an inductive follow-up device 15, applied through lead 16 to one channel of an amplifier 17. Amplifier 17, which is of the type described in Specification 662,831, includes thermionic valves 54, 61, 62, which derive their H.T. supply from a rectifier valve 77, and magnetic amplifiers 72, 73 which derive their A.C. supply from a source 71. To prevent false operation of motor 20 in the event of failure of the H.T. supply from rectifier 74, a relay 88, which is normally energized from rectifier 74, is de-energized and opens contacts 90, 9] to de-energize phase winding 19 of motor 20. At the same time closure of contacts 92, 93 of relay 88 switches on a warning lamp 95. The ailerons and elevators of the aircraft are controlled from a gyro vertical 27 through addition channels of amplifier 17 in a manner similar to that in which the rudder is controlled. Turn of the craft is produced by a manual controller 14 which injects signals into all amplifier channels.