GB2233738A

GB2233738A - Valve assemblies

Info

Publication number: GB2233738A
Application number: GB8920856A
Authority: GB
Inventors: Pankaj Gupta; Salil Gupta
Original assignee: INTEL GASGARDS
Current assignee: INTEL GASGARDS
Priority date: 1989-06-27
Filing date: 1989-09-14
Publication date: 1991-01-16
Also published as: GB8920856D0

Abstract

A valve assembly comprises an inlet 3 and an outlet 4 for fluid, a main pressure responsive valve 9 for controlling communication between the inlet and outlet and which is arranged to be maintained open for so long as the pressure of fluid in the inlet is above a predetermined level and to close and remain closed when the pressure is below the predetermined level, and an auxiliary valve 19 which is operable to open communication between the inlet and the outlet when the inlet pressure is below the predetermined level and the main valve is closed 9. The valve assembly may comprise a generally cylindrical body 2 having a transverse wall 12 between the inlet and the outlet and provided with two openings 8, 10, one controlled by the main valve member 9 and the other controlled by the valve member 19 which is manually rotatable about the axis of the body to open and close the opening. The valve assembly is intended for use between a fluid utilising means and a supply of fluid of finite capacity, e.g. a cylinder of liquefied gas or a tank of liquid, which is such that the pressure of the fluid therefrom reduces as the supply is depleted. The main valve 9 is intended to cut off the flow of fluid to the utilising means before the supply is exhausted to warn the user that the supply is nearly exhausted. The flow of fluid can be reinstated, while a replacement supply is being organised, by manual operation of the auxiliary valve 19. <IMAGE>

Description

Improvements in and relating to Valve Assemblies The present invention relates to a device particularly but not exclusively for use in a fluid utilising system comprising fluid utilising means supplied with fluid from a container or other supply of finite capacity which is such that the pressure of the fluid from the supply reduces as the supply is depleted, and for alerting the user when the supply is nearly empty.

According to the present invention there is provided a device comprising a valve assembly having an inlet and an outlet for insertion in a fluid supply line and comprising a main pressure responsive valve which is arranged to be maintained open permitting communication between the inlet and the outlet for so long as the pressure of the fluid at the inlet is above a predetermined level and to close and remain closed when the pressure at the inlet is below the said level, and an auxiliary valve which is operable to control communication between the inlet and the outlet when the pressure in the fluid is below the predetermined level and the main valve is closed.

The device may comprise a body provided with the inlet and outlet, the inlet and outlet being connected by main passage means provided with the main valve and auxiliary passage means provided with the auxiliary valve.

The auxiliary valve is preferably arranged to be operable by means accessable externally of the device and which may be manually engageable.

The main and auxiliary passage means may be arranged in parallel between the inlet and the outlet.

Alternatively, the auxiliary passage means may be provided in a part of the main valve.

The above device may, for example, be incorporated in a gas utilising system comprising gas utilising means supplied with gas from a cylinder of liquefied gas. The main valve is arranged to close to prevent flow of gas from the cylinder, and shut down the gas utilising means, at a predetermined pressure where there is still liquefied gas remaining in the cylinder. This shut down of the gas utilising means warns the user of the approaching need to replace the cylinder. Meantime however the user can operate the auxiliary valve to reinstate the supply of gas to the gas utilising means.

The above described device may alternatively be incorporated in a liquid utilising system comprising liquid utilising means supplied with liquid from a container, e.g. a tank, of liquid. The main valve is arranged to close to prevent flow of liquid from the container, and shut down the utilising means, at a predetermined pressure where there is still liquid remaining in the container. This shut down of the liquid utilising means warns the user of the approaching need to refill the container. Meantime however the user can operate the auxiliary valve to reinstate the supply of liquid to the utilising means.

The device may be incorporated in such a system adjacent the utilising means or adjacent the fluid supply.

It may for example be incorporated in a fluid pressure regulator if conventionally included in such a system.

Further features and advantages of the present invention will become apparent from the following description of an embodiment thereof, given by way of example only, with reference to the accompanying drawings in which: Figure 1 is a section through an embodiment of a device according to the present invention; Figure 2 is a section through part of the device of Figure 1, showing the device in an alternative position; Figure 3 is a view in the direction of the arrow III of Figure 1; Figures 4 and 5 are sections on the lines IV-IV and V-V of Figures 1 and 2; Figure 6 is a section through a gas pressure regulator incorporating the device of Figure 1; Figure 7 is a section through another embodiment of a device according to the present invention; and Figure 8 is a section on the line VIII-VIII of Figure 7.

The device 1 shown in Figures 1 to 5 comprises a body 2 having an inlet 3 and an outlet 4 for fluid and which is adapted for insertion in a fluid supply line.

As shown, the body 2 is externally generally cylindrical with a hexagonal flange 6 at the inlet end and the device is designed to be inserted into a duct 5 (shown in broken lines in Figure 1) through which fluid flows with the flange 6 of the body 2 seating in a correspondingly hexagonal portion of the duct, to prevent rotation of the device, and an annular seal 7 extending around the other end of the body sealing against a shoulder in the duct 5. The body 2 may alternatively be designed to provide an inlet and outlet which are adapted, e.g. screw threaded, for connection to sections of a fluid supply pipe.

The body 2 defines a main passage 8 which is controlled by a main pressure responsive valve 9 and, in parallel with main passage 8, an auxiliary passage 10 controlled by a manually operable auxiliary valve 11.

As shown, the body 2 has an internal wall 12 which is provided with a first cylindrical opening defining passage 8. The portion 2a of the body on the inlet side of wall 12 is internally generally cylindrical and has an axis 13a coaxial with its external surface. The portion 2b of the body on the outlet side of wall 12 is also internally generally cylindrical but has an axis 13b parallel to but displaced from the axis of the inlet side.

Passage 8 is coaxial with portion 2b. A valve member 14 of the main valve 9 is axially slidably received in the portion 2b of the body and is biased by a spring 15 towards a position in which it seats against the outlet end of passage 8 closing passage 8 against the pressure of fluid in the inlet 3. The valve member 14 is provided with a resilient, e.g. rubber, generally conical sealing disc 16 which seals against wall 12 and the member 14 is located laterally within portion 2b of body 2 by radial ribs or fins 17. The spring 15 acts between body 14 and an apertured plug 18 which is threaded into the outlet end of the body 2 and is adjustable in position to adjust the biasing force on valve member 14 so as to enable adjustment of the predetermined inlet pressure at which the valve member 14 will close passage 8.

The internal wall 12 has a second opening defining auxiliary passage 10. The valve 11 controlling communication through auxiliary passage 10 comprises a rotatable member 19 which is received in portion 2a of the body 2.

As shown, passage 10 is laterally elongate. It may alternatively comprise two adjacent cylindrical openings, as shown in broken lines in Figure 4.

Member 19 is provided with a central opening 20 which is inclined to axis 13a so that, in the position shown in Figure 1, it will fully align with passage 8.

Member 19 also has a radial channel 22 extending from the central opening which, with the member 19 rotated to the position shown in Figure 2, provides communication between the inlet 3 and the auxiliary passage 10. With the member 19 rotated to a position in which channel 22 is out of alignment with passage 10, as shown in Figure 1, communication between the inlet 3 and outlet 4 via passage 10 is closed. The two positions of member 19 shown in Figures 1 and 2 are for example spaced by 900. Sealing between member 19 and wall 12 is provided by a resilient disc 23, e.g. of rubber, held axially fixed relative to wall 12 and which has an opening 24 aligned with passage 8 and an opening 25 aligned with passage 10.

Member 19 is held against disc 23 and wall 12 by a compression spring 26 bearing between member 19 and a retaining member 27 threaded into the inlet end of body 2.

The auxiliary valve 11 is operated by means which engage member 19 so as to rotate it between a position in which the radial channel 22 is aligned with auxiliary passage 10 and a position in which the two are out of alignment. In this embodiment, member 19 is axially extended by an annular operating member 28 having a central passageway 29 communicating with opening 20 in member 19 and which is provided at its outer end with a filter 30. Operating member 28 is made axially fast with valve member 19. For example its inner end may be a press fit within an annular flange 19a on the member 19.

In this embodiment the outer end of the operating member is provided with a pair of ears 31 between which an eccentric operating element 32 rotatable about axis 13a is received for rotating the operating member 28 and valve member 19. It will however be appreciated that the member 19 may be rotated in a variety of different ways and can be appropriately adapted for this purpose.

The device as shown in Figures 1 to 5 may be incorporated in a fluid utilising system between the fluid supply, e.g. a cylinder of liquefied gas or a tank of liquid, and the fluid utilising means, for example in the region of the utilising means or in the region of the supply. In a system with a fluid pressure regulator for regulating the pressure of fluid supplied to the utilising means, it may for example conveniently be incorporated in the pressure regulator.

A conventional gas pressure regulator incorporating the above described device is shown in Figure 6. As is conventional, the regulator comprises a housing 40 having an inlet 41 for connection to the outlet of a gas cylinder, and an outlet 42 for connection to the gas utilising means. Within housing 40 is the pressure regulating means comprising a diaphragm 43 controlling a valve 44 which in turn controls flow of gas from inlet 41 to outlet 42 to maintain the pressure in the outlet 42 approximately constant. In inlet 41 there is a valve 45 movable between open and closed positions by an eccentric element 46 on the end of a rod 47 rotatable about axis 48, the rod 47 projecting out of housing 40 and being provided at its end with a knob 49 for manual operation.Conventionally knob 49 is movable between two positions in one of which the valve 45 is opened and the other of which the valve 45 is closed and it is also, conventionally, provided with a spring biased detent or releasable locking system for positive location of the knob 49 in the two positions.

The device 1 described above is as shown inserted in the passage 50 connecting inlet 41 to the valve 44 and is arranged so that the eccentric element 46 engages between the ears 31 of member 28 of the device of Figure 1, and forms the element 32 shown in Figure 1. The radial channel 22 is arranged so that it is out of alignment with passage 10 in the two conventional positions of knob 49 and the knob 49 has a third position to which it can be rotated to bring channel 22 into alignment with passage 10 and thus open the auxiliary valve.

These three positions may, for example, be angularly spaced by 900.

In use of the above described gas pressure regulator, the gas utilising means connected to the regulator is used as is conventional until the pressure in the cylinder connected to inlet 41 drops to the level preset by adjustment of spring 15 of the device 1. At this point the main valve 9 will close and the supply of gas to the gas utilising circuit will cease indicating to the user that his supply of gas is running low. Meantime, while arranging provision of a new cylinder, the user can continue to use the gas utilising means by bypassing the main valve 9 by rotating knob 49 to its third position opening the auxiliary valve 11.

In a modification of the above described regulator the device may be incorporated in the regulator downstream of the regulating means, for example is a passage between the regulating means and the outlet.

In relation to the device as shown in Figures 1 to 5, it will be appreciated that the axes of the two portions 2a, 2b of the body are laterally displaced in order to minimise the overall diameter of the body.

Where there is no need to minimise the diameter of the body, the portions 2a, 2b can be coaxial. Additionally, while as described above the auxiliary valve is manually operated, it will be appreciated that its operation may be effected by remotely controlled drive means.

The device 61 shown in Figures 7 and 8 comprises a body 62 having an inlet 63 and an outlet 64 adapted for connection in a pipe for fluid and defining a main passage means 65 between the inlet and the outlet which is controlled by a main pressure responsive valve 66, and an auxiliary passage means 67, parallel to the main passage means and which is controlled by an auxiliary valve 68.

The main valve comprises a diaphragm valve comprising a diaphragm 69 mounted in the body 62 and which defines with the body a chamber 70 forming part of the main passage means 65 which also comprises an inlet duct 71 to the chamber and an outlet duct 72 from the chamber and which opens into the chamber through an opening 73.

Associated with the opening 73 is a valve member 74 which is coupled to move with the diaphragm 69. The valve member 74 has a disc 75 of resilient material, e.g.

rubber, which, when the valve member 74 closes the opening 73 seats on and seals against a lip 76 surrounding the opening 73.

That face of diaphragm 69 exposed to chamber 70 is subject to the pressure of the fluid flowing into the device through inlet 63 which tends to bias the diaphragm 69 upwardly (as shown in Figure 7) in a direction to move the valve member 74 away from the opening 73 to permit flow of fluid from the inlet 63 to the outlet 64.

The diaphragm 69 is subject on its other face to the force of a compression spring 77 which acts between a central disc 78 of the diaphragm 69 and a member 79 threaded into the body 62. Member 79 is provided on the end of a shaft 80 which extends outside the body and is provided at its outer end with a manually graspable knob 81 for rotating member 79 to adjust the compression of spring 77 and thereby adjust the force the spring exerts on the diaphragm 69 and therefore adjusts the inlet pressure at which the valve will close.

A compression spring 82 may be provided acting on the valve member 74 to assist in opening of the main valve following its closure for whatever reason.

The auxiliary valve 68 in the auxiliary passage means 67 comprises a valve body 83. The valve body 83 is generally frustoconical and is sealingly received in a correspondingly frustoconical recess 84 in the body 62, the recess 84 being arranged with its axis perpendicular to the axis of the passage 67. The valve body 83 is rotatable in recess 84 about the axis of the recess and has a bore 85 extending transversely therethrough which is aligned with the passage 67 in the open position of the valve to open communication therethrough between the inlet 63 and the outlet 64, the valve being rotatable to an angularly displaced closed position in which the bore 85 is out of alignment with the passage 67 to close communication between the inlet and the outlet.The valve body 83 is held in position by a compression spring 86 acting between the valve body and a plate 87 closing the recess 84 in the body 62. The valve body 83 is extended by a shaft 88 projecting out through an opening in the plate and terminating outside the body in a manually graspable knob 89 for operation of the valve.

The above described device may also be incorporated in a fluid, e.g. a gas or liquid, utilising system which is supplied with fluid from a container or other supply of finite capacity, e.g. a cylinder of liquefied gas or a tank of liquid, which is such that the pressure of the fluid from the supply reduces as the supply is depleted, e.g. the level of liquid drops, the supply being connected to inlet 63 and the fluid utilising means, comprising one or more fluid utilising devices, being connected to the outlet 64.In such circumstances, the diaphragm valve is initially arranged so that the force exerted on diaphragm 69 by the spring 77 is such, relative to the pressure of the fluid in the inlet, that the diaphragm 69 will move to a position in which the valve member 74 closes the opening 73 when the pressure in the inlet is above the lowest useful pressure, e.g. before all the liquefied gas from the cylinder or substantially all the liquid from the tank, has been used. When the pressure at inlet 37 drops to this level the diaphragm valve will close shutting down the fluid utilising means connected to outlet 64. This alerts the user to the need to replace or replenish the supply but meantime the fluid supply to the fluid utilising means can be reinstated by rotating the knob 89 in a direction to open the auxiliary valve.

Because the diaphragm 69 is exposed to inlet pressure at all stages of operation of the diaphragm valve, the diaphragm valve can be made to be very sensitive to pressures and pressure changes. For example it may be sensitive to pressures of the order of 200 mm water column and to pressure changes of the order of 1 mm water column.

The above described device may be incorporated in a fluid utilising system at any convenient position between the supply and utilising means. Where the system includes a fluid pressure regulator, the device may be located upstream or downstream of the regulator. By way of example, the device may be mounted on the or one of the fluid utilising means.

Where the fluid is a gas, the gas may for example by a liquefied petroleum gas, the utilising means comprising a gas burner, e.g. for cooking. Where the fluid is a liquid, the liquid may for example be petrol, the utilising means being an engine, e.g. of a vehicle.

Claims

CLAIMS:

1. A device comprising a valve assembly having an inlet and an outlet, for insertion in a fluid supply line and comprising a main pressure responsive valve which is arranged to be maintained open permitting communication between the inlet and the outlet for so long as the pressure of the fluid at the inlet is above a predetermined level and to close and remain closed when the pressure at the inlet is below the said level, and an auxiliary valve which is operable to control communication between the inlet and the outlet when the pressure in the fluid is below the predetermined level and the main valve is closed.

2. A device as claimed in claim 1, comprising manually operable operating means for operating the auxiliary valve.

3. A device as claimed in claim 1, comprising a body provided with the inlet and an outlet, the inlet and outlet being connected by main passage means provided with the main pressure responsive valve, wherein an auxiliary passage means is provided between the inlet and the outlet which is provided with the auxiliary valve.

4. A device as claimed in claim 3, comprising operating means for operating the auxiliary valve, the operating means being accessable externally of the body.

5. A device as claimed in either claim 3 or claim 4, wherein the main and auxiliary passage means are arranged in parallel between the inlet and the outlet.

6. A device as claimed in any of claims 3 to 5, wherein the body is generally annular and has an internal transverse wall between the inlet and the outlet and provided with a main opening defining the main passage, the main valve comprising a main valve member movable within the body between a first position closing the opening and a second position in which fluid can flow through the opening.

7. A device as claimed in claim 6, wherein the main valve member is arranged in the body downstream of the transverse wall, is movable away from the transverse wall to its second position, is biassed by spring means to its first position and in its first position has a surface exposed to the inlet pressure through the main opening.

8. A device as claimed in any of claim 3 to 6, wherein the transverse wall is provided with an auxiliary opening defining the auxiliary passage and the auxiliary valve comprises an auxiliary valve member movable between a first position closing the auxiliary opening and a second position in which fluid can flow through the auxiliary opening.

9. A device as claimed in claim 8, wherein the auxiliary valve member is rotatable about an axis perpendicular to the transverse wall between its two positions.

10. A device as claimed in claim 9, wherein the auxiliary valve member overlies the transverse wall on the inlet side thereof, is.provided with an opening communicating with the inlet and for alignment with the main opening in the transverse wall in the first position of the auxiliary valve member, the opening in the auxiliary valve member being adapted to communicate with the auxiliary opening in the wall when the auxiliary valve member is in its second position.

11. A device as claimed in claim 10, comprising resilient sealing means interposed between the transverse wall and the auxiliary valve member for sealing therebetween.

12. A device as claimed in any of claims 9 to 11, wherein the auxiliary valve member has an axially extending projection for engagement by the operating means.

13. A device as claimed in any of claims 3 to 12 for insertion in a fluid supply passage, wherein the body is generally externally cylindrical and provided with sealing means for sealing against the wall of the passage, the ends of the body being open and providing the inlet and outlet respectively.

14. A device as claimed in claim 5, wherein the main valve comprises a diaphragm defining with the main passage means a chamber in communication with the inlet, one face of the diaphragm being subject to the pressure of fluid in the inlet.

15. A device as claimed in claim 14, wherein the diaphragm carries a main valve member for closing an opening providing communication between the chamber and the outlet.

16. A device as claimed in claim 15, wherein the diaphragm is biased by a spring in a direction to move the valve member to close the opening against the force of the pressure of the fluid on the diaphragm.

17. A device as claimed in claim 16, wherein the bias provided by the spring is adjustable to adjust the pressure of the fluid at which the main valve member will close the opening.

18. A device as claimed in any of claims 14 to 17, wherein the auxiliary valve comprises a rotatable valve member rotatable between a position in which the auxiliary passage is open and a position in which the auxiliary passage is closed.

19. A device as claimed in claim 18, wherein the auxiliary valve member is rotatable about an axis perpendicular to the axis of the auxiliary passage means.

20. A device as claimed in either claim 18 or claim 19, wherein the auxiliary valve member has operating means projecting externally of the body of the device for operation of the auxiliary valve member.

21. A device substantially as herein described with reference to the accompanying drawings.

22. A fluid pressure regulator comprising an inlet for connection to a supply of fluid whose pressure is to be regulated, pressure regulating means, an outlet, a passage connecting the inlet to the pressure regulating means, and a device as claimed in'any one of claims 1 to 13 located in the passage.

23. A regulator as claimed in claim 22, comprising a manually operable valve in the inlet of the regulator and manually operable means for operating the valve, wherein the auxiliary valve is arranged to be operated by the manually operable means for operating the manually operable valve.

24. A fluid pressure regulator comprising an inlet for connection to a supply of fluid whose pressure is to be regulated, pressure regulating means, an outlet, a passage connecting the pressure regulating means to the outlet, and a device as claimed in any of claims 1 to 13 located in the passage.

25. A fluid pressure regulator substantially as herein described with reference to the accompanying drawings.

26. A fluid utilising system comprising fluid utilising means connected to be supplied with fluid from a supply of finite capacity which is such that the pressure of the fluid from the supply reduces as the fluid in the supply is depleted and a device as claimed in any of claims 1 to 21 connected between the supply outlet and the fluid utilising means, wherein the main valve is arranged to close to prevent flow of fluid from the supply at a predetermined pressure at which there is still fluid remaining in the supply.

27. A system as claimed in claim 26, comprising pressure regulating means between the supply and the utilising means, the device being incorporated in the pressure regulating means.

28. A system as claimed in either claim 26 or claim 27, wherein the fluid is a gas and the supply comprises a container of liquefied gas.

29. A system as claimed in either claim 26 or claim 27, wherein the fluid is a liquid and the supply comprises a tank for liquid.

30. A fluid utilising system comprising fluid utilising means connected to be supplied with fluid from a supply of finite capacity which is such that the pressure of the fluid from the supply reduces as the fluid in the supply is depleted and a fluid pressure regulator as claimed in any of claims 22 to 25 connected between the supply outlet and the fluid utilising means, wherein the main valve is arranged to close to prevent flow of fluid from the supply at a predetermined pressure at which there is still fluid remaining in the supply.