Claims for Patent: 3,800,534

Summary for Patent: 3,800,534

Title:	AUXILIARY HYDRAULIC POWER SUPPLY
Abstract:	An emergency hydraulic power supply for an aircraft or the like, including a hydraulic pump arranged to be driven by a turbine in turn driven by hot gas from a decomposition chamber, a fuel pump driven by the turbine for supplying fuel to the decomposition chamber, primary flow control valve means in the pump outlet for controlling fuel flow responsive to turbine speed, an ignition chamber communicable with the decomposition chamber and having a start grain for initiating turbine operation to start the fuel pump, a secondary control valve in the pump outlet, and control means for sensing turbine speed and opening the secondary valve when the turbine attains a speed indicating the start grain has about burned out, and closing the secondary valve in the event that the turbine attains a speed indicating the primary flow control valve means is inoperative to control turbine speed.
Inventor(s):	Kacek; Donald J. (Rockford, IL)
Assignee:	Sundstrand Corporation (Rockford, IL)
Application Number:	05/238,352
Patent Claims:	1. An auxiliary power supply system, comprising, a. a turbine wheel adapted to be driven by hot gas to provide mechanical power, b. a chamber for decomposition of fuel to produce hot gas, c. a hot gas conduit connecting the decomposition chamber and the turbine wheel to supply hot gas to drive the wheel, d. a fuel pump driven by the turbine wheel for supplying fuel to the decomposition chamber, e. a fuel outlet conduit connecting the pump outlet and the decomposition chamber, f. a fuel tank for storing fuel to be supplied to the decomposition chamber, g. a fuel inlet conduit connecting the fuel tank and the pump inlet, h. a start chamber communicable with the decomposition chamber for containing starting fuel for initiating turbine operation to start the fuel pump, i. flow control valve means in the outlet conduit responsive to turbine speed for regulating fuel flow from the pump to the decomposition chamber to control turbine speed, j. a secondary control valve in one of said conduits for blocking fuel flow between the tank and the decomposition chamber, k. control means responsive to the speed of the turbine for opening the secondary control valve when the turbine attains a predetermined minimum speed. 2. An auxiliary power supply system as defined in claim 1, wherein the flow control valve means comprises a valve member responsive to pressure increase in the fuel pump outlet for reducing fuel flow to the decomposition chamber and responsive to pressure decrease in the pump outlet for increasing fuel flow to the decomposition chamber, thereby to maintain constant turbine speed. 3. An auxiliary power supply system as defined in claim 2, including control means responsive to the speed of the turbine for closing the secondary control valve in event the turbine speed exceeds a predetermined maximum permissible value. 4. An auxiliary power supply system as defined in claim 1, wherein the secondary control valve is located in the outlet conduit between the pump and the decomposition chamber. 5. An auxiliary power supply system as defined in claim 1, wherein the control means comprises electrical means for sensing the speed of the turbine and a solenoid responsive to the sensing means for operating the secondary control valve. 6. An emergency hydraulic power supply system for an aircraft, comprising, a. a turbine wheel adapted to be driven by hot gas, b. a hydraulic pump driven by the turbine wheel to supply hydraulic fluid to an aircraft hydraulic system, c. a chamber for decomposition of fuel to produce hot gas, d. a hot gas conduit for supplying hot gas from the decomposition chamber to the turbine wheel, e. an exhaust for conducting spent gas from the turbine wheel to atmosphere, f. a fuel pump driven by the turbine wheel for supplying fuel to the decomposition chamber, g. a fuel outlet conduit connecting the pump outlet and the decomposition chamber, h. a fuel tank for storing fuel to be supplied to the decomposition chamber, i. a fuel inlet conduit connecting the fuel tank and the pump inlet, j. means for pressurizing the fuel tank, k. an ignition chamber communicable with the decomposition chamber for holding a start grain for initiating turbine operation to start the fuel pump, l. flow control valve means in the outlet conduit responsive to turbine speed for regulating fuel flow to the decomposition chamber to maintain constant turbine speed, m. a secondary control valve in said outlet conduit normally blocking communication between the fuel pump and the decomposition chamber, and n. control means responsive to the speed of the turbine for opening the secondary control valve when the turbine attains a predetermined minimum speed. 7. An emergency hydraulic power supply system for an aircraft as defined in claim 6, wherein means for pressurizing the fuel tank comprises a conduit leading from the hot gas conduit for supplying hot gas under pressure to the fuel tank. 8. An emergency hydraulic power supply system for an aircraft as defined in claim 6, including control means responsive to the speed of the turbine for closing the secondary valve in event the turbine speed exceeds a predetermined maximum value. 9. An emergency hydraulic power supply system for an aircraft as defined in claim 8, wherein the secondary control valve comprises a valve member normally biased toward a position blocking communication between the fuel pump and the decomposition chamber, and a solenoid for moving the valve member to valve open position, and the control means comprises electrical means for sensing turbine speed and energizing the solenoid when the turbine attains a speed indicating the start grain has about burned out and deenergizing the solenoid when the turbine attains a speed indicating the flow control valve means is inoperative.