Magnetically damped valve system

Abstract

A valve comprising a housing (12), a valve closure member (30) and a magnetic damping device (50) comprising a fixed member (52) and a moveable member (54). The fixed member (52) is fixed in position relative to the housing (12), and the moveable member (54) is configured to move with the closure member (30). One of the fixed member (52) or the moveable member (54) comprises a magnetic field generator, and the other of the fixed member (52) or the moveable member (54) comprises an electrical conductor. The magnetic damping device (50) is configured so that the electrical conductor is exposed to the magnetic field of the magnetic field generator. A pressure regulator (10, 110) comprising such a valve. A method and control system (100) for controlling the damping of the pressure regulator (110) when the magnetic field generator comprises an electromagnet (152) in dependence on the rate of change of fluid flow demand on the outlet side (22) of the pressure regulator (110).

Description

[0001] Magnetically Damped Valve System

[0002] Field of the invention

[0003] The present invention relates to damped valve systems, and more particularly to magnetically damped valve systems. The present invention also relates to a magnetically damped pressure regulator and to a system and method for controlling the regulator.

[0004] Background to the invention

[0005] Uncontrolled vibration in mechanical systems is undesirable as it can lead to unexpected system behaviour, unwanted noise, unwanted pressure waves, and may potentially cause damage to the system if left unchecked. It is well known to control unwanted vibrations in mechanical systems by the use of one or more dampers with the object of limiting, or ideally eliminating, the vibrations.

[0006] In fluid control systems, variations in flow and / or pressure can cause the valve or valves in the system to vibrate which may, in turn, cause vibration throughout the system. An example use of a valve within a fluid control system is within the fuel pressure regulator of a fuel injection system. The fuel pressure regulator is located between the fuel tank and the fuel rail and has the task to keep the pressure upstream of the fuel injectors almost independent of engine fuel demand. This is achieved by careful design of a diaphragm / piston and spring arrangement within the fuel pressure regulator. Even so, in fast transient scenarios the fuel pressure regulator may struggle to keep pace with a rapid change in fuel demand resulting in the valve oscillating about its equilibrium position and generating unwanted outlet pressure variation. To guard against such unwanted pressure variations, damping is required.

[0007] Valves which control the flow of higher viscosity fluids are damped to a certain extent by the fluid itself as it moves through the valve. An example of this is diesel within the fuel pressure regulator of a fuel injection system. However, systems for controlling non-viscous, or low viscosity, fluids are not able to benefit from this type of damping.

[0008] It is against this background that the invention is devised. Statements of the invention

[0009] According to an aspect of the present invention, a valve is provided which comprises a housing and a closure member, wherein the closure member is configured to move in a first direction relative to the housing to open the valve and in a second opposite direction relative to the housing to close the valve, wherein the valve comprises a magnetic damping device comprising a fixed member and a moveable member, wherein the fixed member is fixed in position relative to the housing, and wherein the moveable member is configured to move with the closure member, wherein one of the fixed member or the moveable member comprises a magnetic field generator, and the other of the fixed member or the moveable member comprises an electrical conductor, wherein the magnetic damping device is configured so that at least part of the electrical conductor is exposed to the magnetic field generated by the magnetic field generator.

[0010] Advantageously, the relative movement between the moveable member and the fixed member generates eddy currents in the electrical conductor as the magnetic field encountered by the electrical conductor changes as a result of the relative movement between the fixed and moveable members. The eddy currents in the electrical conductor in turn produce a magnetic field that is opposite to the magnetic field produced by the magnetic field generator. The opposing magnetic fields act to resist the relative movement between the fixed member and the moveable member thereby damping the movement of the closure member relative to the valve housing by dissipating its kinetic energy to achieve the equilibrium point quickly.

[0011] Optionally, the moveable member may be connected to, embedded in, or integral with the closure member. This facilitates multiple design options for the valve. It may be advantageous for the moveable member to be connected to the closure member in an assembly to minimise valve part cost. Alternatively, it may be advantageous for the moveable member to be embedded in or integral with the closure member to facilitate more rapid assembly and to provide a more robust valve with fewer individual parts.

[0012] A portion of the fixed member may be received in a recess located within an inner wall of the housing.

[0013] The magnetic field generator may optionally comprise a permanent magnet or may optionally comprise an electromagnet. The use of a permanent magnet is advantageous as there is no requirement for an electrical supply. Conversely, the use of an electromagnet enables the magnetic field to be adjusted so that the level of damping may be adjusted according to the operating conditions of the valve.

[0014] The fixed member may encircle at least part of the moveable member to help maximise the volume of interaction between the moveable and fixed members thereby enabling the electrical conductor to interact with the magnetic field more effectively.

[0015] In one example, the fixed member may be located between a pair of flux bridge elements which extend from the housing towards the moveable element. The provision of such flux bridges is beneficial as the magnetic fields produced by the magnetic field generator and by the eddy currents induced in the electrical conductor are concentrated in the vicinity of the bridges thereby enhancing the damping effect caused by the interaction of the two magnetic fields.

[0016] The flux bridge elements may protrude beyond the fixed member to carry the flux closer to the moveable member thereby further enhancing the damping effect.

[0017] The housing may comprise a non-ferromagnetic material which advantageously prevents the flux from travelling a long distance through the housing and dissipating. This concentrates the magnetic fields in the vicinity of the flux bridge elements thereby enhancing the damping effect caused by the interaction of the two magnetic fields.

[0018] The valve may optionally comprise a control spring which extends between the housing and the moveable member to provide a force to act with or against the motion of the closure member (depending on the design of the valve) via the moveable member.

[0019] A portion of the moveable member may be configured to be received within the control spring to provide a reliable connection between the moveable member and the control spring and to assist in assembly of the valve.

[0020] In one example, the closure member may comprise a valve head and a valve stem, wherein the moveable member is fixed to, embedded in, or integral with the valve stem. This structure conveniently allows for the moveable member to be located away from the valve head which may be desirable for packaging and operational purposes.

[0021] According to another aspect of the present invention, there is provided a pressure regulator, wherein the pressure regulator comprises an inlet located on an inlet side of the pressure regulator and an outlet located on an outlet side of the pressure regulator, wherein the inlet and the outlet are in selective fluidic communication in dependence on the position of the closure member. This advantageously provides a pressure regulator able to damp valve oscillations effectively even when used to regulate low viscosity or compressible fluids.

[0022] Optionally, the housing may define a control chamber, wherein the control chamber comprises a first portion and a second portion separated by a diaphragm or a piston, wherein the outlet is located in the first portion of the control chamber, and wherein the closure member is configured to move with the diaphragm or piston in accordance with the balance of forces across the diaphragm or piston in use. Fluid flow on the outlet side of the of the pressure regulator is consequently limited to the first portion of the control chamber leaving the second portion of the control chamber free of fluid.

[0023] The magnetic damping device may optionally be located in the second portion of the control chamber where it may be conveniently packaged and separated from fluid located in the first portion.

[0024] A portion of the fixed member may be received in a recess located within an inner wall of the housing.

[0025] In one example, when the control chamber is separated by a diaphragm, a portion of the diaphragm may be received together with the portion of the fixed member in the recess. This helps to fluidically seal the first portion of the control chamber from the second portion of the control chamber.

[0026] According to another aspect of the present invention, there is provided a control system for controlling a pressure regulator as described above, wherein the magnetic field generator comprises an electromagnet, the control system comprising one or more controllers, the control system configured to: receive a first input signal indicative of a rate of change of fluid flow demand on the outlet side of the pressure regulator; determine a damping characteristic in dependence on the first input signal; determine a power supply characteristic in dependence on the determined damping characteristic; and issue a control signal to control a supply of electrical power to the electromagnet in accordance with the determined power supply characteristic.

[0027] The control system advantageously controls the electromagnet, thereby controlling its associated magnetic field strength, in dependence on the rate of change of fluid flow demand on the outlet side of the pressure regulator. Consequently, the amount of damping provided by the magnetic damping device is also controlled in dependence on the rate of change of fluid flow demand on the outlet side of the pressure regulator allowing the damping to be optimised for a given engine running condition and / or fuel demand.

[0028] The one or more controllers may collectively comprise: at least one electronic processor having at least one electrical input for receiving the input signal; and at least one memory device electrically coupled to the at least one electronic processor and having instructions stored therein; wherein the at least one electronic processor is configured to access the at least one memory device and execute the instructions thereon so as to: determine the damping characteristic in dependence on the first input signal; determine the power supply characteristic in dependence on the determined damping characteristic; and issue the control signal to control the supply of electrical power to the electromagnet in accordance with the determined power supply characteristic.

[0029] According to a still further aspect of the present invention, a method is provided for controlling a pressure regulator as described above, wherein the magnetic field generator comprises an electromagnet, the method comprising: receiving a first input indicative of rate of change of fluid flow demand on the outlet side of the pressure regulator; determining a damping characteristic in dependence on the first input; determining a power supply characteristic in dependence on the determined damping characteristic; and controlling a supply of electrical power to the electromagnet in accordance with the determined power supply characteristic.

[0030] According to another aspect of the present invention, there is provided a vehicle comprising the valve as described above, the pressure regulator as described above, or the control system as described above.

[0031] According to yet another aspect of the present invention, computer software is provided that, when executed, is arranged to perform the method described above.

[0032] According to a still further aspect of the present invention, there is provided a non-transitory, computer-readable storage medium storing instructions thereon that, when executed by one or more electronic processors, causes the one or more electronic processors to carry out the method for controlling the pressure regulator described above.

[0033] Brief description of the drawings A non-limiting example of the present invention will now be described with reference to the following drawings in which:

[0034] Figure 1 shows a schematic sectional side view of a pressure regulator according to the present invention;

[0035] Figure 2 shows the pressure regulator of Figure 1 additionally comprising condition sensors;

[0036] Figure 3 shows a block diagram of a control system for controlling the pressure regulator of Figure 2; and

[0037] Figure 4 shows a schematic illustration of a vehicle in accordance with an embodiment of the present invention.

[0038] Detailed description

[0039] Figure 1 shows a fuel pressure regulator 10 comprising a housing 12, an inlet 14 and an outlet 16. In this example, the housing 12 comprises an upper portion 13 and a lower portion 15 (in the orientation of Figure 1). However, this is not essential and the housing 12 may be formed of a single piece, or may be formed of three or more pieces.

[0040] The housing 12 comprises a plate 18 which separates an inlet side 20 of the pressure regulator 10 from an outlet side 22 of the pressure regulator 10. As shown, the inlet 14 is located on the inlet side 20 of the pressure regulator 10, and the outlet 16 is located on the outlet side 22 of the pressure regulator 10. The plate 18 has an opening 19 which provides selective fluidic communication between the inlet 14 and the outlet 16 in dependence on the position of valve closure member 30. The opening 19 has a frusto-conical shape with its largest diameter located towards the inlet side 20 of the pressure regulator 10, and its smallest diameter located towards the outlet side 22 of the pressure regulator 10.

[0041] The valve closure member 30 comprises a valve head 32 and a valve stem 34. The valve head 32 is frusto-conical in form and configured to conform to the frusto-conical opening 19 in plate 18. Consequently, when the closure member 30 is in the closed position, the frusto- conical surface of the valve head 32 seats on the frusto-conical surface of the opening 19 to prevent fluid passing from the inlet side 20 of the pressure regulator 10 to the outlet side 22 of the pressure regulator 10. The opening 19 therefore constitutes the valve seat of a valve comprising the housing 12 and closure member 30.

[0042] The housing 12 on the outlet side 22 of the pressure regulator 10 defines a control chamber 40 which is separated into a first portion 42 and a second portion 44 by a diaphragm 46. The outlet 16 is located in the first portion 42 of the control chamber 40 on the outlet side 22 of the pressure regulator 10. The peripheral edge of the diaphragm 46 is located in a recess 11 located within an inner wall of the housing 12. The valve stem 34 of the closure member 30 passes through the diaphragm 46. The diaphragm 46 is sealed about the valve stem 34 and the recess 11 so that no fluid may pass from the first portion 42 of the control chamber 40 into the second portion 44 of the control chamber 40. The valve stem 34 is constrained to move with the diaphragm 46 so that, as the diaphragm 46 moves in use, so does the valve stem 34 and valve head 32.

[0043] A magnetic damping device 50 is located in the second portion 44 of the control chamber 40. The magnetic damping device 50 comprises a fixed member 52 and a moveable member 54. The fixed member 52 comprises an annular ring which encircles the moveable member 54. An outer portion of the fixed member 52 is received together with the diaphragm 46 in the recess 11 in the inner wall of the housing 12. The moveable member 54 comprises an annular ring mounted on and constrained to move with the valve stem 34.

[0044] A control spring 25 extends between a boss 26 located on an inner surface of the housing 12 and the moveable member 54. The valve stem 34 of the closure member 30 is slidably received within a channel 27 located in the boss 26. The moveable member 54 comprises a reduced diameter portion 55 which defines a shoulder 56 against which the control spring 25 bears. The boss 26 and the reduced diameter portion 55 of the moveable member 54 hold the control spring 25 in position between the housing 12 and the moveable member 54. The control spring acts to bias the valve head 32 in the open position.

[0045] The fixed member 52 of the magnetic damping device 50 comprises a permanent magnet, and the moveable member 54 comprises an electrical conductor. As a result of this, in use, as the moveable member 54 moves with respect to the fixed member 52 (as the closure member 30 operates to open or close the valve), eddy currents are produced in the electrically conductive moveable member 54 as it moves through the magnetic field generated by the magnetic fixed member 52. The eddy currents generated in the moveable member 54 themselves generate a magnetic field. In accordance with Lenz’s law, the direction of the eddy currents in the moveable member 54 is such that the magnetic field created by the eddy currents opposes changes in the magnetic field generated by the fixed member 52. Consequently, movement of the moveable member 54 (and therefore movement of the closure member 30) is resisted by the opposing magnetic fields. Movement of the closure member 30 is thereby damped.

[0046] The fixed member 52 is located between a pair of disc shaped flux bridges 58, the peripheral edges of which are located together with the fixed member 52 and the diaphragm 46 in the recess 11 of the housing 12. The flux bridges 58 extend beyond the fixed member 52 and terminate close to the moveable member 54, to direct the flux from the flux bridges 58 to the moveable member 54. The flux bridges 58 comprise a ferromagnetic material, wherein the ferromagnetic material is preferably iron or an iron-based material. The housing 12 can comprise any material, but preferably not a ferromagnetic material to prevent the flux from travelling a long distance through the housing 12 and dissipating. The moveable member 54 can comprise the same material as that of the flux bridges 58, but preferably comprises a different material, such as aluminium or copper, to prevent it from being attracted to the permanent magnet 52. Although in the current embodiment the flux bridges 58 are flat disc shaped, in other embodiments the flux bridges 58 may have a different profile. For example, the flux bridges 58 may have a wavy or curved profile.

[0047] The magnetic fields - created by the fixed member 52 and the eddy currents induced in the moveable member 54 - are concentrated in the flux bridges 58 in a specific region of space close to the moveable member 54. This helps to amplify the damping effect since, as the movable member 54 moves up or down with the closure member 30, a new part of the moveable member 54 moves into the region of concentrated flux. This sudden interaction with the flux causes the electrically conductive material to resist the movement by generating eddy currents that try to cancel out the flux. In addition, the part of the electrically conductive material that was under the influence of the region of concentrated flux resists moving out of this region by generating eddy currents to resist the movement.

[0048] In use, fuel enters the pressure regulator 10 via the inlet 14 and exits the pressure regulator 10 via the outlet 16. The amount of fuel demanded by the engine at any given time is dependent on the operating conditions of the engine. As a result, in certain operating conditions, the fluid pressure on the outlet side of the pressure regulator 10 may drop. When this happens, the control spring 25 acts against the fuel pressure acting on the underside of the diaphragm 46 and pushes the closure member 30 down (in relation to the orientation of Figure 1) thereby moving the valve head 32 off the valve seat formed by the opening 19 in the plate 18. When this happens, fuel is able to flow from the inlet side 20 to the outlet side 22 of the pressure regulator 10 thereby restoring the pressure on the outlet side 22. As the fuel pressure rises on the outlet side 22, the fuel pressure acting on the underside of the diaphragm 46 overcomes the force of the control spring 25 causing the valve head 32 to move towards the closed position. The closure member 30 is thereby configured to move with the diaphragm 46 in accordance with the balance of forces across the diaphragm 46.

[0049] The example shown in Figure 1 and described above is one example of the application of a magnetically damped valve assembly. It will be understood that the use of magnetically damped valves is not limited to use within a fuel pressure regulator, and the skilled person will understand that magnetically damped valves may be used in other fluid control systems.

[0050] The skilled person will understand that there are many possible variations to the example described above. For example, the fixed member 52 could be an electromagnet rather than a permanent magnet. The fixed member 52 could be the electrically conductive element of the magnetic damping device 50 and the moveable member 54 could be the magnetic field generator (either as a permanent magnet or an electromagnet).

[0051] The magnetically damped valve assembly described above and shown in Figure 1 comprises flux bridges 58 which concentrate the magnetic flux. In another example (not shown) the flux bridges may be omitted.

[0052] In the example described above, only one magnetic damping device 50 is shown. However, it will be understood that more than one magnetic damping device 50 could be used to damp a single valve. Alternatively or additionally, the magnetic damping device could comprise a plurality of fixed and / or moveable members.

[0053] The magnetic damping device 50 is shown located in the second portion 44 of the control chamber 40. In another example one or more magnetic damping devices 50 could be located in the first portion 42 of the control chamber 40 instead of, or in addition to, the magnetic damping device 50 located in the second portion 44 of the control chamber 40.

[0054] In an alternative example, the moveable member 54 could be embedded in or integrally formed with the closure member 30. The closure member 30 could itself comprise the moveable member 54. It is well known to use fuel pressure regulators having a moveable piston attached to the valve stem 34 of the closure member 30 instead of a diaphragm 46. It will be understood that the magnetic damping device 50 described above may equally be used in such fuel pressure regulators.

[0055] Referring now to Figure 2, a fuel pressure regulator 110 is illustrated. The fuel pressure regulator 110 is the same in most respects to the fuel pressure regulator 10 shown in Figure 1 and like reference numerals have been used to indicate like features.

[0056] The fuel pressure regulator 110 comprises a magnetic damping device 150 which comprises an electromagnetic fixed member 152 and an electrically conductive moveable member 54 attached to the closure member 30. Wires 153 are connected to the electromagnetic fixed member 152 to supply electrical power from an electricity supply (not shown). The magnetic damping device 150 operates in the same way as described above in respect of magnetic damping device 50 when the electromagnetic fixed member 152 is provided with an electric current. As will be described in greater detail below, the level of damping provided can be controlled by the magnetic damping device 150 by controlling the electrical power supply to the electromagnetic fixed member 152.

[0057] Sensors 120, 122 for sensing a condition on the inlet side 20 and the outlet side 22 of the pressure regulator 110 respectively are provided. The sensors 120, 122 may be configured to sense fluid pressure, flow rate, temperature or any other condition of the fluid as may be desired. The sensors 120, 122 are configured to generate signals indicative of the fluid condition on their respective sides of the pressure regulator 110. A wired or wireless connection (not shown) is provided to facilitate transmission of the sensor signals to a controller which may be an engine control unit (ECU). It will be understood that the location of the sensors 120, 122 is for illustrative purposes only and that the sensors 120, 122 need not be located within the housing and may, instead, be located in the inlet 14 or the outlet 16, or the pipes connected thereto, respectively. For example, the outlet side pressure sensor 122 may be located in the fuel rail. Alternatively, additional sensors (not shown) may be located in the upstream / downstream pipes and / or fuel rail

[0058] Figure 3 shows an example control system 100 for controlling the supply of electrical power to the electromagnetic fixed member 152. As described above, each of the sensors 120, 122 is configured to generate input signals indicative of a fluid condition on the inlet side 20 and the outlet side 22 of the pressure regulator 110 respectively. In this example, the sensor 120 on the inlet side 20 is configured to generate an input signal 121 indicative of the fluid pressure on the inlet side 20 of the pressure regulator 110, and the sensor 122 on the outlet side 22 is configured to generate an input signal 123 indicative of the pressure on the outlet side 22 of the pressure regulator 110.

[0059] An additional sensor 124 for sensing the flow rate of the fuel is located in the fuel rail 202 (Figure 4) downstream of the pressure regulator 110. The sensor 124 is configured to generate an input signal 125 indicative of the flow rate in the fuel rail 202. The input signals 121 , 123, 125 from the pressure sensors 120, 122 and the flow sensor 124 are supplied as inputs to a controller 130 via a wired or wireless communication link. The controller 130 comprises a processor 132 and a memory device 134 which is electrically coupled to the processor 132. The memory device 134 has instructions 136 stored therein, and the processor 132 is configured to access the memory device 134 and execute the instructions 136 thereon.

[0060] The inputs 121 , 123, 125 from the sensors 120, 122, 124 are supplied as inputs to the processor 132 which is configured to access the memory device 134 and execute the instructions 136 thereon so as to determine a damping characteristic in dependence on the input signals 121 , 123, 125, determine a power supply characteristic in dependence on the determined damping characteristic, and issue a control signal 138 to control a supply of electrical power to the electromagnet 152 in accordance with the determined power supply characteristic.

[0061] Specifically, the controller 130 is configured to determine a rate of change of fluid flow demand on the outlet side 22 of the pressure regulator 110 using the input signal 125 generated by the flow sensor 124. The controller 130 is configured to then determine the required damping characteristic in dependence on the rate of change of fluid flow demand on the outlet side 22 of the pressure regulator 110, and the indicated inlet and outlet pressure signals 121 , 123. The controller 130 is configured to then determine the power supply characteristic in dependence on the determined damping characteristic, and issue the control signal 138 to control the supply of electrical power to the electromagnet 152 in accordance with the determined power supply characteristic.

[0062] The control system 100 therefore operates to control the fuel flow in the fuel rail by varying the damping of the magnetic damping device 150 in dependence on the rate of change of fluid flow demand on the outlet side 22 of the pressure regulator 110, and the fuel pressures on the inlet side 20 and outlet side 22 of the pressure regulator 110 respectively. In an alternative example, the controller 130 uses only the input signal 125 from the flow sensor 124 in the fuel rail to determine the rate of change of fluid flow demand on the outlet side 22 of the pressure regulator 110, and to determine the required damping characteristic. Therefore, in this example, the fuel pressure input signals 121 , 123 are not required. In a further alternative example, only one of the fuel pressure input signals 121 , 123 may be used, along with the rate of change of fluid flow demand on the outlet side 22 of the pressure regulator 110, to determine the damping characteristic.

[0063] It will be appreciated that other input signals such as temperature and flow across the regulator 110 may be used by the controller 130 to determine the damping characteristic. One or more of the parameters required by the controller 130 to determine the damping characteristic may be directly received as inputs to the controller 130 from sensors, or may be calculated by the controller 130 as derivatives of the input signals.

[0064] The control system 100 may be a part of, or may be in communication with, the ECU.

[0065] It is to be understood that the control system 100 described above may comprise one or more controllers 130, and that the or each controller can comprise a control unit or computational device having one or more electronic processors (e.g., a microprocessor, a microcontroller, an application specific integrated circuit (ASIC), etc.), and may comprise a single control unit or computational device, or alternatively different functions of the or each controller may be embodied in, or hosted in, different control units or computational devices. As used herein, the term “controller,” “control unit,” or “computational device” will be understood to include a single controller, control unit, or computational device, and a plurality of controllers, control units, or computational devices collectively operating to provide the required control functionality. A set of instructions 136 could be provided which, when executed, cause the controller to implement the control techniques described herein (including some or all of the functionality required for the method described herein). The set of instructions could be embedded in said one or more electronic processors 132 of the controller; or alternatively, the set of instructions could be provided as software to be executed in the controller. A first controller or control unit may be implemented in software run on one or more processors. One or more other controllers or control units may be implemented in software run on one or more processors, optionally the same one or more processors as the first controller or control unit. Other arrangements are also useful.

[0066] The, or each, electronic processor may comprise any suitable electronic processor (e.g., a microprocessor, a microcontroller, an ASIC, etc.) that is configured to execute electronic instructions. The, or each, electronic memory device 134 may comprise any suitable memory device and may store a variety of data, information, threshold value(s), lookup tables or other data structures, and / or instructions therein or thereon. In an embodiment, the memory device has information and instructions for software, firmware, programs, algorithms, scripts, applications, etc. stored therein or thereon that may govern all or part of the methodology described herein. The processor, or each, electronic processor may access the memory device and execute and / or use that or those instructions and information to carry out or perform some or all of the functionality and methodology describe herein.

[0067] The at least one memory device may comprise a computer-readable storage medium (e.g. a non-transitory or non-transient storage medium) that may comprise any mechanism for storing information in a form readable by a machine or electronic processors / computational devices, including, without limitation: a magnetic storage medium (e.g. floppy diskette); optical storage medium (e.g. CD-ROM); magneto optical storage medium; read only memory (ROM); random access memory (RAM); erasable programmable memory (e.g. EPROM ad EEPROM); flash memory; or electrical or other types of medium for storing such information / instructions.

[0068] Example controllers 130 have been described comprising at least one electronic processor 132 configured to execute electronic instructions stored within at least one memory device 134, which when executed causes the electronic processor(s) 132 to carry out the method as hereinbefore described. However, it is contemplated that the present invention is not limited to being implemented by way of programmable processing devices, and that at least some of, and in some embodiments all of, the functionality and or method steps of the present invention may equally be implemented by way of non-programmable hardware, such as by way of nonprogrammable ASIC, Boolean logic circuitry, etc.

[0069] Figure 4 shows a vehicle 200 which comprises an engine 201 , a fuel rail 202 for supplying fuel to the engine 201 , from a fuel tank 203. A pressure regulator 150 is provided to control the fuel pressure in the fuel rail 202. The damping of the pressure regulator 150 is controlled by controller 130. In another embodiment (not shown) the vehicle 200 may comprise fuel pressure regulator 50.

[0070] It will be appreciated that various changes and modifications can be made to the present invention without departing from the scope of the present application.

Claims

Claims1. A valve comprising a housing (12) and a closure member (30), wherein the closure member (30) is configured to move in a first direction relative to the housing (12) to open the valve, and in a second opposite direction relative to the housing (12) to close the valve, wherein the valve comprises a magnetic damping device (50) comprising a fixed member (52) and a moveable member (54), wherein the fixed member (52) is fixed in position relative to the housing (12), and wherein the moveable member (54) is configured to move with the closure member (30), wherein one of the fixed member (52) or the moveable member (54) comprises a magnetic field generator, and the other of the fixed member (52) or the moveable member (54) comprises an electrical conductor, wherein the magnetic damping device (50) is configured so that at least part of the electrical conductor is exposed to the magnetic field generated by the magnetic field generator.

2. A valve as claimed in claim 1 , wherein the moveable member (54) is: connected to the closure member (30); embedded in the closure member (30); or integral with the closure member (30).

3. A valve as claimed in claim 1 or claim 2, wherein the magnetic field generator comprises a permanent magnet.

4. A valve as claimed in claim 1 or claim 2, wherein the magnetic field generator comprises an electromagnet.

5. A valve as claimed in any preceding claim, wherein the fixed member (52) encircles at least part of the moveable member (54).

6. A valve as claimed in any preceding claim, wherein the fixed member (52) is located between a pair of flux bridge elements (58) which extend from the housing (12) towards the moveable element (54).

7. A valve as claimed in any preceding claim, wherein the housing (12) comprises a nonferromagnetic material.

8. A valve as claimed in any preceding claim, comprising a control spring (25), wherein the control spring (25) extends between the housing (12) and the moveable member (54).

9. A valve as claimed in claim 9, wherein a portion (55) of the moveable member (54) is configured to be received within the control spring (25).

10. A valve as claimed in any preceding claim, wherein the closure member (30) comprises a valve head (32) and a valve stem (34), wherein the moveable member (54) is fixed to, embedded in or integral with the valve stem (34).

11. A pressure regulator (10) comprising a valve according to any preceding claim, wherein the pressure regulator (10) comprises an inlet (14) located on an inlet side (20) of the pressure regulator (10) and an outlet (16) located on an outlet side (22) of the pressure regulator (10), wherein the inlet (14) and the outlet (16) are in selective fluidic communication in dependence on the position of the closure member (30).

12. A pressure regulator (10) as claimed in claim 11 , wherein the housing (12) defines a control chamber (40), wherein the control chamber (40) comprises a first portion (42) and a second portion (44) separated by a diaphragm (46) or a piston, wherein the outlet (16) is located in the first portion (42) of the control chamber (40), and wherein the closure member (30) is configured to move with the diaphragm (46) or piston in accordance with the balance of forces across the diaphragm (46) or piston in use.

13. A pressure regulator (10) as claimed in claim 12, wherein the magnetic damping device (50) is located in the second portion (44) of the control chamber (40).

14. A pressure regulator (10) as claimed in claim 12 or 13, wherein a portion of the fixed member (52) is received in a recess (11) located within an inner wall of the housing (12).

15. A pressure regulator (10) as claimed in claim 14, wherein the control chamber (40) is separated by a diaphragm (46), and wherein a portion of the diaphragm (46) is received together with the portion of the fixed member (52) in the recess (11).

16. A control system (100) for controlling a pressure regulator (110) as claimed in any one of claims 11 to 15, wherein the magnetic field generator comprises an electromagnet (152), the control system (100) comprising one or more controllers (130), the control system configured to: receive a first input signal indicative of rate of change of fluid flow demand on the outlet side (22) of the pressure regulator (110);determine a damping characteristic in dependence on the first input signal; determine a power supply characteristic in dependence on the determined damping characteristic; and issue a control signal (138) to control a supply of electrical power to the electromagnet (152) in accordance with the determined power supply characteristic.

17. The control system (100) as claimed in claim 16, wherein the one or more controllers (130) collectively comprise: at least one electronic processor (132) having at least one electrical input for receiving the input signal (121 , 123); and at least one memory device (134) electrically coupled to the at least one electronic processor (132) and having instructions (136) stored therein; wherein the at least one electronic processor (132) is configured to access the at least one memory device (134) and execute the instructions (136) thereon so as to: determine the damping characteristic in dependence on the first input signal; determine the power supply characteristic in dependence on the determined damping characteristic; and issue the control signal (138) to control the supply of electrical power to the electromagnet (152) in accordance with the determined power supply characteristic.

18. A method for controlling a pressure regulator (110) as claimed in any one of claims 11 to 15, wherein the magnetic field generator comprises an electromagnet (152), the method comprising: receiving a first input indicative of rate of change of fluid flow demand on the outlet side (22) of the pressure regulator (110); determining a damping characteristic in dependence on the first input; determining a power supply characteristic in dependence on the determined damping characteristic; and controlling a supply of electrical power to the electromagnet (152) in accordance with the determined power supply characteristic.

19. A vehicle (200) comprising the valve of any of claims 1 to 13, the pressure regulator (10, 110) of any of claims 11 to 15, or the control system (100) of any of claims 16 or 17.

20. Computer software that, when executed, is arranged to perform a method according to claim 18.

21. A non-transitory, computer-readable storage medium (134) storing instructions (136) thereon that, when executed by one or more electronic processors, causes the one or more electronic processors to carry out the method of claim 18.

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