Valve unit and a fluid working machine comprising a valve unit

Patent metadata

Field	Value
Publication number	US-9732748-B2
Application number	US-201414771103-A
Country	US
Kind code	B2
Filing date	Mar 3, 2014
Priority date	Mar 1, 2013
Publication date	Aug 15, 2017
Grant date	Aug 15, 2017

Abstract

A valve unit for regulating the flow of working fluid between a working chamber of a fluid working machine and both a first working fluid line and second working fluid line, the valve unit comprising: a first valve comprising a first valve member and one or more cooperating first valve seats, a second valve comprising a second valve member and one or more cooperating second valve seats, an actuator coupled to both the first and second valve members through which a force may be applied to urge the first valve member open or closed and to urge the second valve member open or closed, a coupling between the actuator and the first valve member, wherein the coupling between the actuator and the first valve member comprises a connector which extends at least partially through the second valve member.

First claim

The invention claimed is:

1. A valve unit for regulating the flow of working fluid between a working chamber of a fluid working machine and both a first working fluid line and a second working fluid line, the valve unit comprising:
a first valve comprising a first valve member and one or more cooperating first valve seats,
a second valve comprising a second valve member and one or more cooperating second valve seats,
an actuator, which is actuatable to apply a force to urge the first valve member away from or towards the one or more first valve seats and a force to urge the second valve member away from or towards the one or more second valve seats,
a coupling between the actuator and the first valve member,
wherein the coupling comprises a connector which extends at least partially through the second valve member.

2. A valve unit according to claim 1 , further comprising an opening in the valve unit through which the first valve and the second valve can communicate with a working chamber, and wherein the first valve member comprises an aperture through which the second valve can communicate with the opening when the first valve member is in sealing contact with the one or more first valve seats.

3. A valve unit according to claim 1 , wherein the second valve member is located intermediate the first valve member and the actuator.

4. A valve unit according to claim one, wherein the actuator is a solenoid actuator.

5. A valve unit according to claim 4 , wherein the second valve member comprises magnetic material and is magnetically coupled to the solenoid actuator such that when current is passed through the solenoid actuator, magnetic flux from the solenoid actuator passes through the second valve member and an opening or closing force is thereby exerted on the second valve member.

6. A valve unit according to claim 4 , wherein the solenoid actuator acts on an armature, the armature is connected to the first valve member by a connector which extends through the second valve member, and the armature is magnetically coupled to the solenoid actuator such that when current is passed through the solenoid actuator, magnetic flux from the solenoid actuator passes through the armature and an opening or closing force is thereby exerted on the first valve member through the connector.

7. A valve unit according to claim 4 , wherein the solenoid actuator acts on an armature, the armature is coupled to a hydraulically actuated member through a hydraulic pressure operated coupling, and the hydraulically actuated member is coupled to the first valve member by the connector.

8. A valve unit according to claim 7 , comprising a chamber defining a volume containing hydraulic fluid, the chamber being defined in part by a surface of the hydraulically actuated member, the hydraulically actuated member being slidably mounted, whereby movement of the armature responsive to actuation by the solenoid leads to a change in hydraulic pressure within the chamber and a consequent movement of the hydraulically actuated member.

9. A valve unit according to claim 8 , wherein the chamber is in communication with a sink or source for hydraulic fluid through a valve and the armature is slidable responsive to actuation by the solenoid to open the valve, to thereby cause hydraulic fluid to enter or leave the chamber and a pressure differential to develop across the hydraulically actuated member.

10. A valve unit according to claim 9 , wherein the valve is a pilot valve and the sink or source for hydraulic fluid comprises a conduit extending through the connector to an opening of the valve unit.

11. A valve unit according to claim 7 , wherein the solenoid actuator acts on an armature and the armature is coupled to the second valve member through a hydraulic pressure operated coupling.

12. A valve unit according to claim 11 , wherein the second valve member is slidably mounted and has a surface in communication with a chamber containing hydraulic fluid, wherein movement of the armature causes a change in the pressure of hydraulic fluid in the chamber, the change in pressure causing said urging of the second valve member away from or towards the one or more second valve seats.

13. A valve unit according to claim 7 , wherein the second valve member is slidably mounted and has a surface in fluid communication with a chamber containing hydraulic fluid, wherein movement of the first valve member or the connector causes a change in the pressure of hydraulic fluid in the chamber, the change in pressure in turn urging the second valve member away from or towards the one or more second valve seats.

14. A valve unit according to claim one, wherein the one or more first and one or more second valve seats are coaxial.

15. A valve unit according to claim one, wherein the first and/or second valve member has two valve seats, which seal a port or ports lying between the two seats.

16. A valve unit according to claim one, wherein the first and second valve members are located within the valve unit.

17. A valve unit according to claim one, comprising one or more flow passages extending at least in part in an outwards direction, for coupling one or more first valve seats to a hydraulic line and/or one or more radially outwards extending flow passages for coupling one or more second valve seats to a hydraulic line.

18. A valve unit according to claim one, wherein the first valve member is an annular valve and the one or more first valve seats are an annular valve seat and the annular first valve member and the annular valve seat are configured to together define inner and outer sealing lines extending around the periphery of the annular first valve member and the annular valve seat when the annular first valve member is in sealing engagement with the annular valve seat.

19. A valve unit according to claim one, configured such that actuation of the actuator causes the first valve to open or close and subsequently causes the second valve to open or close.

20. A valve unit according to claim 19 , wherein opening or closure of the first valve causes the forces exerted by the actuator on the second valve member, whether directly or indirectly, to increase to thereby facilitate subsequent opening or closing of the second valve.

21. A valve unit according to claim one, wherein the connector extends through the second valve member.

22. A valve unit according to claim one, wherein the connector comprises a hydraulic connector.

23. A fluid working machine comprising a low pressure line, a high pressure line, a working chamber, and a valve unit according to any one preceding claim, wherein the first and second valves are in fluid communication with the working chamber and the first and second valve seats are coupled to the low and high pressure lines respectively to thereby regulate the flow of working fluid between the working chamber and the low and high pressure lines.

24. A fluid working machine according to claim 23 , wherein the value unit further comprises an opening in the valve unit through which the first valve and the second valve communicate with the working chamber, and wherein the first valve member comprises an aperture through which the second valve can communicate with the working chamber when the first valve member is in sealing contact with the one or more first valve seats.

Assignees

• Artemis Intelligent Power Ltd

Inventors

• Stein Uwe
• Eilers Jens
• Lavender Jack
• Laird Stephen

Classifications

• F16K31/082

  using a electromagnet and a permanent magnet · CPC title

• F01B29/10

  Engines · CPC title

• F01B31/26

  Other component parts, details, or accessories, peculiar to steam engines · CPC title

• F16K11/04

  comprising only lift valves · CPC title

• F04B19/22

  of reciprocating-piston type · CPC title