Propeller oil control system for aircraft turboprop engines

Patent metadata

Field	Value
Publication number	US-11066150-B2
Application number	US-201816227175-A
Country	US
Kind code	B2
Filing date	Dec 20, 2018
Priority date	Dec 20, 2018
Publication date	Jul 20, 2021
Grant date	Jul 20, 2021

Abstract

A propeller oil control system for a turboprop engine of an aircraft includes an engine control unit and a propeller oil controller. The engine control unit is operable to determine a flight phase of the aircraft and is configured to supply control commands. The propeller oil controller is coupled to receive a supply of oil and to discharge the oil at a discharge oil pressure. The propeller oil controller includes an electrohydraulic servo valve that receives the control commands moves to a plurality of positions between a first position and a mid-position, and a plurality of positions between the mid-position and a second position. The engine control unit only commands the electrohydraulic servo valve to move out of the first position when the engine control unit determines the aircraft is conducting a take-off roll or the aircraft is in flight.

First claim

What is claimed is:

1. A propeller oil control system for a turboprop engine of an aircraft, comprising:
an engine control unit operable to determine a flight phase of the aircraft and configured to supply control commands; and
a propeller oil controller coupled to receive a supply of oil and discharge the oil at a discharge oil pressure, the propeller oil controller further coupled to receive the control commands from the engine control unit and configured, in response to the control commands, to control the discharge oil pressure, the propeller oil controller comprising:
a housing including a pump inlet port, a negative torque system supply outlet port, a drain pressure outlet port, and a control pressure outlet port;
an oil pump rotationally disposed within the housing, the oil pump including a pump inlet and a pump outlet, the oil pump adapted to receive a drive torque and configured, upon receipt of the drive torque, to draw oil into the pump inlet and discharge pressurized oil out of the pump outlet at a pump discharge pressure;
a pressure regulating valve disposed within the housing and configured to regulate the pump discharge pressure; and
an electrohydraulic servo valve coupled to the housing and including at least a regulated oil inlet port, a drain pressure oil outlet port, and a valve outlet port, the regulated oil inlet port in fluid communication with the pressure regulating valve to thereby receive the pressurized oil at the regulated pump discharge pressure, the valve outlet port in fluid communication with the control pressure outlet port, the electrohydraulic servo valve further coupled to receive the control commands and configured, in response thereto, to move to (i) a plurality of positions between a first position and a mid-position, and (ii) a plurality of positions between the mid-position and a second position,
wherein:
in the first position and in the plurality of positions between the first position and the mid-position, the regulated oil inlet port is in fluid communication with the control pressure outlet port via the valve outlet port,
in the mid-position, the regulated oil inlet port is not in fluid communication with the control pressure outlet port,
in the second position and in a plurality of positions between the second position and the mid-position, the drain pressure oil outlet port is in fluid communication with the control pressure outlet port, and
the engine control unit only commands the electrohydraulic servo valve to move out of the first position when the engine control unit determines the aircraft is conducting a take-off roll or the aircraft is in flight.

2. The propeller oil control system of claim 1 , further comprising:
a pressure relief valve disposed between the pump inlet port and the negative torque system supply outlet port, the pressure relief valve configured to place the pump outlet in fluid communication with the pump inlet port when pump discharge pressure reaches a predetermined pressure magnitude.

3. The propeller oil control system of claim 2 , wherein the pressure relief valve is disposed within the pressure regulating valve.

4. The propeller oil control system of claim 1 , wherein the electrohydraulic servo valve further comprises a null spring, the null spring applying a force to the valve element that urges the valve element toward the first position.

5. The propeller oil control system of claim 4 , wherein the electrohydraulic servo valve comprises:
a valve body including the regulated oil inlet port, the drain pressure oil outlet port, the valve outlet port, the valve body further including a drain pressure chamber, and an inner surface that defines a valve element chamber, the valve element chamber including a first control chamber and a second control chamber;
a valve element disposed within the valve element chamber and movable to the plurality of positions between the first position, the mid-position, and the second position, the valve element including a first end and a second end, the first end disposed within the first control chamber, the second end disposed within the second control chamber;
a first control conduit defined in the valve body and having a first control port disposed within the drain pressure chamber, the first control conduit fluidly communicating the drain pressure chamber with the first control chamber;
a second control conduit defined in the valve body and having a second control port disposed within the drain pressure chamber, the second control conduit fluidly communicating the drain pressure chamber with the second control chamber;
a control nozzle having an inlet port and an outlet port, the inlet port in fluid communication with the regulated oil inlet port, the outlet port disposed in the drain pressure chamber and adjacent to the first control port and the second control port, the control nozzle moveable within the drain pressure chamber to control pressure in the first and second control conduits to thereby control pressure in the first and second control chambers, respectively, whereby movement of the valve element is controlled; and
a control element coupled to the control nozzle, the control element further coupled to receive the control commands and configured, in response thereto, to move the control nozzle.

6. The propeller oil control system of claim 5 , wherein the control element comprises a torque motor.

7. The propeller oil control system of claim 5 , wherein the null spring is disposed within the first control chamber.

8. The propeller oil control system of claim 1 , wherein the oil pump comprises a gerotor pump.

9. The propeller oil control system of claim 1 , further comprising:
a check valve disposed between the pump outlet and the regulated oil inlet port, the check valve movable between an open position, in which the regulated oil inlet port is in fluid communication with the pressure regulating valve, and a closed position, in which the regulated oil inlet port is not in fluid communication with the pressure regulating valve.

10. The propeller oil control system of claim 9 , further comprising:
a check valve bias spring that supplies a bias force to the check valve that urges the check valve toward the closed position.

11. The propeller oil control system of claim 5 , wherein:
the control element comprises a torque motor; and
the null spring is disposed within the first control chamber.

12. The propeller oil control system of claim 1 , wherein the oil pump comprises a gerotor pump.

13. The propeller oil control system of claim 1 , further comprising:
a check valve disposed between the pump outlet and the regulated oil inlet port, the check valve movable between an open position, in which the regulated oil inlet port is in fluid communication with the pressure regulating valve, and a closed position, in which the regulated oil inlet port is not in fluid communication with the pressure regulating valve; and
a check valve bias spring that supplies a bias force to the check valve that urges the check valve toward the closed position.

14. A propeller oil control system for a turboprop engine of an aircraft, comprising:
an engine control unit operable to determine a flight phase of the aircraft and configured to supply control commands; and
a propeller oil controller coupled to receive a supply of oil and discharge the oil at a discharge oil pressure, the propeller oil controller further coupled to receive the control commands from the engine control unit and configured, in response to the control commands, to control the discharge oil pressure, the propeller oil controller comprising:
a housin

Assignees

• Honeywell Int Inc

Inventors

• Futa Jr Paul W
• Tillich Sammuel
• Lewis Steven Alan
• Eick Christopher Douglas
• Striker Donald
• Mcpherson Michael Albert

Classifications

• B64C11/40

  automatic · CPC title

• B64C11/385 Primary

  comprising feathering, braking or stopping systems · CPC title

• F02C6/206

  the vehicles being airscrew driven · CPC title

• B64C11/44

  electric · CPC title

• F02D29/02

  peculiar to engines driving vehicles; peculiar to engines driving variable pitch propellers · CPC title