Pressure regulator valve

1. An air-to-air refuelling reception coupling comprising a main body arranged for connection to a refuelling hose, the main body of the reception coupling comprising

an opening disposed towards an end of the main body, the opening being sized and arranged for receiving at least partially into the opening a refuelling probe of a receiver aircraft;

a fuel passage for fuel having an inlet and an outlet, the outlet being provided adjacent the opening;

a valve for opening the outlet to deliver the fuel, the valve comprising a concave probe-receiving portion for receiving a probe of a receiver aircraft, wherein the valve is sized and arranged to be opened by action on the valve probe-receiving portion of a refuelling probe of a receiver aircraft received at least partially into the opening;

the main body of the air-to-air refuelling reception coupling including a pressure regulator valve arrangement, which comprises

at least one pressure port in fluid communication with the fuel passage and

a first pressure regulator valve and a second pressure regulator valve,

the first pressure regulator valve comprising:

a first actuator member, and

a first valve member coupled to the first actuator member, wherein the first valve member is arranged to extend into the fuel passage in order to restrict the flow of the fuel in response to pressure at the at least one pressure port reaching a predetermined pressure, and

the second pressure regulator valve comprising:

a second actuator member, and

a second valve member coupled to the second actuator member, wherein the second valve member is arranged to extend into the fuel passage in order to restrict the flow of fuel in response to pressure at the at least one pressure port reaching the predetermined pressure,

wherein the at least one pressure port is arranged downstream of both of the first and second valve members;

wherein the first and second pressure regulator valves are arranged for operation independently of each other and wherein each of the first and second pressure regulator valves is arranged to regulate to the same predetermined pressure;

wherein the first and second actuator members are responsive to pressure at the at least one pressure port;

wherein each of the first and second actuator members is configured to cause the respective one of the first and second valve members to move in a first direction to restrict the flow of fuel in the fuel passage, and each of the first and second actuator members is biased towards a second direction that is opposite to the first direction.

2. An air-to-air refuelling reception coupling as claimed in claim 1 , in which the at least one pressure port is arranged for closing the fuel passage in response to pressure and is formed in a central body surrounded by the fuel passage.

3. An air-to-air refuelling reception coupling as claimed in claim 2 , in which the at least one pressure port includes an open end of the central body.

4. An air-to-air refuelling reception coupling as claimed in claim 2 , in which the at least one pressure port extends through a surface extending around a circumference of the central body.

5. An air-to-air refuelling reception coupling as claimed in claim 2 , in which

the central body includes a first valve chamber and a second valve chamber, the fuel passage being in fluid communication with at least one of the first and second valve chambers via the at least one pressure port; and

the first and second actuator members of the first and second pressure regulator valves are disposed in the first and second valve chambers respectively.

6. An air-to-air refuelling reception coupling as claimed in claim 1 , in which the first and second pressure regulator valves and the at least one pressure port are formed in a central body surrounded by the fuel passage.

7. An air-to-air refuelling reception coupling as claimed in claim 1 , in which the first valve member is axially movable relative to the main body of the reception coupling for closing the fuel passage, and the second valve member is axially movable relative to the main body of the reception coupling for closing the fuel passage, wherein the first and second valve members are arranged for independent movement relative to the main body from one another.

8. An air-to-air refuelling reception coupling as claimed in claim 1 , in which the fuel passage is annular, and the first and second valve members are sleeve shaped.

9. An air-to-air refuelling reception coupling as claimed in claim 8 , in which the first and second valve members are concentrically arranged open-ended sleeves.

10. An air-to-air refuelling reception coupling as claimed in claim 9 , in which one of the first and second valve members is at least partially disposed within the other of the first and second valve members.

11. An air-to-air refuelling reception coupling as claimed in claim 9 , in which the first and second valve members are at least partially nested one within the other so that the overall axial extent of the first and second valve members when nested is less than the sum of the separate axial extents of each of the first and second valve members.

12. An air-to-air refuelling reception coupling as claimed in claim 1 , in which the fuel passage is curved such that the first and second valve members are arranged to cross the fuel passage on axial movement of the first and second valve members relative to the main body.

13. An air-to-air refuelling reception coupling as claimed in claim 1 , in which the first and second valve members are adjacent one another.

14. An air-to-air refuelling reception coupling as claimed in claim 8 , in which the first and second valve members are adjacent one another and are concentrically arranged open-ended sleeves such that one of the first and second valve members is radially exterior to the other of the first and second valve members.

15. An air-to-air refuelling reception coupling as claimed in claim 1 , in which the valve members are both adjacent the inlet of the fuel passage.

16. An air-to-air refuelling reception coupling as claimed in claim 1 , in which the first and second actuator members are mounted in a central body surrounded by the fuel passage.