GB829873A - Improvements in and relating to temperature control and pressurisation systems for aircraft cockpits - Google Patents

Abstract

829,873. Ventilating aircraft. ENGLISH ELECTRIC CO. Ltd. Dec. 7, 1956 [Dec. 9, 1955], No.35520/55. Class 137 [Also in Groups XIII and XXXIII] In a temperature control and pressurization system, for cabins &c. of aircraft designed to fly at extreme speeds and altitudes, ram air is fed through a primary refrigerator evaporator 1 to a two-way valve 33 leading either to a secondary evaporator 2 or a by-pass 34. The ram air then passes through non-return and control valves 35, 36 respectively to a manifold 37 for distribution to a general air supply 38, personal supplies 39 to the members of a crew, and window sprays 39<SP>1</SP> of a cabin 31. The refrigerant circulating through the secondary evaporator 2 passes through a double-walled cooling shield 30 which is secured to structural frames within the cabin 31 and then through an opening 29 to a constant back-pressure valve 28 and a dump 20 which is driven by a hydraulic motor 21. The pump 20 supplies coolant to a condenser 22 and then to a temperature control throttle valve 23 which is connected to the input side of the evaporator 2. The primary evaporator 1 is arranged in a separate refrigerating circuit between two other evaporators 14, 16 installed respectively in fore and aft equipment bays the remainder of the circuit being completed by a temperature control throttle valve 13, a condenser 12, a pump 10 driven by a hydraulic motor 11, and a constant back-pressure valve 18. Both of the condensers 12, 22 rare placed in heat exchange with comparatively cool liquid fuel of the aircraft propulsion system. Fans 15, 19 circulate air respectively over 'the evaporators 14, 16. The aft equipment bay is supplied with compressed air which is derived from a high pressure compressor stage of a turbo-jet propulsion engine 40 and is passed through non-return and reduction valves 41, 42 respectively to a desiccant canister 43 and then to the aft bay. A relief-valve 44 is arranged in a branch line 44 between the reduction valve 42 and the desiccant canister 43. The circuits are duplicated for safety.