초록 ▼

Audio noise created by trim valves (66a-72a) in a warm air trim system (24) of an air cycle air conditioning system (10) is reduced by controlling the pressure drop across the trim valves as a function of the position of the valves (66a-72a). A proportional valve (112) typically under the control of

Audio noise created by trim valves (66a-72a) in a warm air trim system (24) of an air cycle air conditioning system (10) is reduced by controlling the pressure drop across the trim valves as a function of the position of the valves (66a-72a). A proportional valve (112) typically under the control of an electronic controller (116) is controlled to set the pressure drop across the trim valves. Reducing the pressure drop across the trim valves, reduces the noise created by air flowing through the trim valves thereby reducing noise in an aircraft cabin.

대표청구항 ▼

An air cycle air conditioning system for providing conditioned air to a plurality of zones in a vehicle cabin, the temperature of each of the plurality of zones is individually controlled by mixing cool air from a central source with warm trim air, creating a plurality of conditioned air flows, with

An air cycle air conditioning system for providing conditioned air to a plurality of zones in a vehicle cabin, the temperature of each of the plurality of zones is individually controlled by mixing cool air from a central source with warm trim air, creating a plurality of conditioned air flows, with each zone receiving one of the plurality of conditioned air flows, the system comprising: pressure sensing means, for sensing pressure in a first pipe, and for providing a pressure signal indicative thereof; controller means, responsive to said pressure signal and a plurality of position feedback signals, for providing a regulating valve area command signal, and for providing a plurality of trim valve area command signals; regulating valve means, responsive to said regulating valve area command signal, for receiving warm pressurized air from an inlet pipe, for controlling the flow rate of said warm pressurized air by modulating the area through which said warm pressurized air passes, and for providing a regulated flow of warm air into said first pipe; and a plurality of trim valves, each of said trim valves receiving a portion of said regulated flow of warm air, each of said trim valves having a variable area through which said portion of said regulated flow of warm air enters at a trim valve inlet and exits at a trim valve outlet, each of said trim valves being responsive to a corresponding one of said plurality of trim valve area command signals in varying the area thereof, said plurality of position feedback signals being indicative of the area that each of said trim valves is open, each of said trim valves providing a warm air flow into a corresponding one of said outlets, whereby each of said warm air flows is mixed with the cool air from the central source to create the plurality of conditioned air flows which enter the plurality of zones.