NZ611126B2 - A Liquid Control Valve - Google Patents

Abstract

liquid pressure control valve includes a body 1A, 1B that forms a cavity, inlet and outlet ports 2, 3 joining to the cavity, and a flexible diaphragm 10 held within the cavity and displaceable to seal at 10F against the end 6 of annular wall of the inlet port to separate the inlet from the outlet when the valve is closed. The diaphragm also forms, with the housing, a chamber 4 that is separated from the outlet port. When the valve is intended to be closed fluid from the inlet is allowed to “bleed” into the chamber through a valved passage 9 by actuation of the control pin 8 by movement of the actuating arm 7, to pressurize the chamber 4 and force the diaphragm to seal the inlet port thus closing the valve. To open the valve the pin 8 is moved by the actuating arm 7 so that fluid from the inlet cannot enter the chamber 4 and fluid in the chamber can bleed via the passage 9 to the ambient. A slide 12 is mounted within the cavity and is coupled to a section of the diaphragm 10 that surrounds the seal and is displaceable with displacement of the diaphragm, though the displacement of the slide is limited by a stop 11/14 once the seal has seated over the inlet port to close the valve. when the valve is closed. The diaphragm also forms, with the housing, a chamber 4 that is separated from the outlet port. When the valve is intended to be closed fluid from the inlet is allowed to “bleed” into the chamber through a valved passage 9 by actuation of the control pin 8 by movement of the actuating arm 7, to pressurize the chamber 4 and force the diaphragm to seal the inlet port thus closing the valve. To open the valve the pin 8 is moved by the actuating arm 7 so that fluid from the inlet cannot enter the chamber 4 and fluid in the chamber can bleed via the passage 9 to the ambient. A slide 12 is mounted within the cavity and is coupled to a section of the diaphragm 10 that surrounds the seal and is displaceable with displacement of the diaphragm, though the displacement of the slide is limited by a stop 11/14 once the seal has seated over the inlet port to close the valve.

Description

A LIQUID CONTROL VALVE TECHNICAL FIELD This invention relates to liquid pressure control valves and in particular such valves that include a flexible element that is displaced by liquid pressure acting on a face thereof to close against a valve seat to provide a closed mode for the valve.

BACKGROUND OF THE INVENTION Liquid pressure control valves of this nahire are well known for the control of water pressure, the flexible member typically being a diaphragm. A drawback with these valves is the possibility that excess closing pressure may cause the flexible member to collapse or distort and thus destroy its closing capability. Extreme cases have resulted in the flexible member fracturing necessitating replacement. To overcome or at least limit these problems it is known to provide a rigid backing element, typically a metal plate, associated with the flexible member to prevent or at least effectively limit excessive displacement or distortion thereof.

Such an arrangement is disclosed in our patent NZ Patent # 328862. A drawback with providing such a plate is that it can tend to impede the liquid flow through the valve.

Other problems with existing liquid pressure valves include too many parts making them difficult to assemble and manufacture or repair. Yet other problems include diaphragms getting damaged because of inadequate support and causing constrictions to the flow.

In this specification unless the contrary is expressly stated, where a document, act or item of knowledge is referred to or discussed, this reference or discussion is not an admission that the document, act or item of knowledge or any combination thereof was at the priority date, publicly available, known to the public, part of common general knowledge; or known to be relevant to an attempt to solve any problem with which this specification is concerned.

An object of this invention is to provide a liquid pressure control valve that includes a flexible member as aforesaid and which also includes a displacement and distortion limiting element therefor that has minimal if any impediment on the flow through the valve or the object of the invention is to provide the public with a useful choice.

ON2303NZA_Amnd_CompSpec_13Aug2014_EHB.doc In this specification unless the contrary is expressly stated, where a document, act or item of knowledge is referred to or discussed, this reference or discussion is not an admission that the document, act or item of knowledge or any combination thereof was at the priority date, publicly available, known to the public, part of common general knowledge; or known to be relevant to an attempt to solve any problem with which this specification is concerned.

Object of the invention It is therefore an object of the present invention to provide an improved complete safety system applicable to constmctions; that ameliorates some of the disadvantages and limitations of the known art or at least to provide the public with a useful choice.

DISCLOSURE OF THE INVENTION According to a first embodiment of this invention, a liquid pressure control valve including a body forming a cavity and incorporating an inlet port and an outlet port joining to the cavity forming a flow path for a liquid there through, a flexible member retained within the cavity to extend over the inlet port, to separate the inlet port from the outlet port and to also form a chamber separated from the outlet port, a controlled bleed passage joining the inlet to the chamber, other than in an open position of the valve, whereby inlet pressure in the chamber will displace the flexible member toward a closed position with a seal of the flexible member seated over the inlet port, within the open position the bleed passage venting the chamber, characterised in that a slide is mounted within the cavity and is coupled to a section of the flexible member surrounding the seal of the inlet port thereof as to be displaced with displacement of the flexible member and a stop to prevent closing displacement of the slide after the flexible member has seated and sealed over the inlet port in the closed position, wherein the flexible member is in the form of a diaphragm with a body retaining an outer peripheral section of the diaphragm, the diaphragm including a central dished section surrounded by an annular wall section disposed substantially normal to the central dished section with a junction of these two sections forming the seal, the slide being coupled to the annular wall section of the diaphragm to enable the diaphragm with the slide to move out of the flow path to achieve maximum fluid flow through the valve.

ON2303NZA_Amnd_CompSpec_13Aug2014_EHB.doc Preferably the valve seat is spaced radially inward and also longitudinally of the outer periphery of the diaphragm with the longitudinal spacing being commensurate to the depth of the dishing of the central section of the diaphragm.

Preferably a section of the diaphragm adjacent to the peripheral section thereof incorporates at least one annularly disposed wave formation to facilitate longihidinal displacement of the central section of the diaphragm.

Preferably a valve adapted to be operated by either a float or a near neutral buoyancy weight connected to an achiator arm pivotally mounted to the body to reciprocally operate a pin, the pin including a pair of longitudinally spaced apart grooves, mounted in the bleed passage between a valve open mode and a valve closed mode, to that end the bleed passage including a pair of complementary longitudinally spaced apart seals to seal against the pin, whereby in the closed mode a first of the seals is bridged by a first of the grooves to join the inlet to the chamber and the second groove is disposed clear of the second seal which thus closes a vent from the chamber and, in an open mode, the first groove is disposed clear of the first seal to close the bleed passage between the inlet and the chamber and the second groove is disposed to bridge the second seal to vent the chamber.

Preferably the inlet terminates with an annular wall extending into the cavity with the inner end thereof forming the valve seat and the surrounding section of the cavity wall forms a bore, the slide being annulariy shaped to surround the inner wall and be a working fit within the bore.

Preferably the slide includes an inwardly extending annular shoulder at a forward end thereof, the inner wall of the shoulder including a rebate in which an enlargement on the diaphragm locates to couple the slide and diaphragm together.

Preferably the longitudinal spacing of seat relative to the outlet and the length of the slide provide that, with displacement of the diaphragm to the fully open mode, the slide is spaced clear of the outlet.

Preferably the stop is disposed to come into play just before complete closure of the valve, full closure requiring some minimal compression of the diaphragm.

ON2303NZA_Amnd_CompSpec_13Aug2014_EHB.doc According to a second embodiment of the invention there is provided a valve as described in the preceding paragraph wherein the flexible member is in the form of a diaphragm with the body retaining an outer peripheral section of the diaphragm, the diaphragm including a central dished section formed by an annular wall section disposed substantially normal to the central section with the junction of these two sections forming the seal, the slide being coupled to the annular wall section of the diaphragm.

According to a third embodiment of the invention there is provided liquid pressure control valve including a body forming a cavity and incorporating an inlet port and an outlet port joining to the cavity, a flexible member retained within the cavity to extend over the inlet port to separate the inlet port from the outlet port and to also form a chamber separated from the outlet port, a controlled bleed passage joining the inlet to the chamber other than in an open mode of the valve, whereby inlet pressure in the chamber will displace the flexible member toward a closed mode with a seal of the flexible member seated over the inlet port, and in the open mode the bleed passage venting the chamber, an actjating arm pivotally mounted to the body to reciprocally operate a pin including a pair of longrtudinally spaced apart grooves mounted in the bleed passage with the bleed passage including a pair of complementary longitudinally spaced apart seals to seal against the pin, whereby in the closed mode a first of the seals is bridged by a first of the grooves to join the inlet to the chamber and the second groove is disposed clear of the second seal which thus closes a vent from the chamber and, in an open mode, the first groove is disposed clear of the first seal to close the bleed passage between the inlet and the chamber and the second groove is disposed to bridge the second seal to vent the chamber, a slide mounted within the cavity and coupled to a section of the flexible member surrounding the seal thereof as to be displaced with displacement of the flexible member, and a stop to prevent closing displacement of the slide after the seal has seated over the inlet port.

According to a fourth embodiment of the invention there is provided liquid pressure control valve as described in any one of the three immediately preceding paragraphs adapted to be operated by either a float or a near neutral buoyancy weight connected to an actuator arm pivotally mounted to the body to reciprocally operate a pin, including a pair of longitudinally spaced apart grooves, mounted in the bleed passage between a valve open mode and a valve closed mode, to that end the bleed passage including a pair of complementary longitudinally spaced apart seals to seal against the pin, whereby in the closed mode a first of the seals is ON2303NZA_Amnd_CompSpec_13Aug2014_EHB.doc bridged by a first of the grooves to join the inlet to the chamber and the second groove is disposed clear of the second seal which thus closes a vent from the chamber and, in an open mode, the first groove is disposed clear of the first seal to close the bleed passage between the inlet and the chamber and the second groove is disposed to bridge the second seal to vent the chamber.

BMEF DESCRIPTION OF THE INVENTION In further describing the invention reference is made to the accompanying drawings wherein; Fig 1 is a cross-sectional view depicting the valve in a closed mode, Fig 2 is a cross-sectional view depicting the valve in an open mode.

Fig 3 is a perspective view of the valve of the present invention in a closed mode as in fig 1.

Fig 4 is a perspective view of the valve of the present invention in an open mode as in fig 2.

BEST MODE OF CARRYING OUT THE INVENTION A valve suitable for controlling a pressurised inlet water supply to a typical farm reservoir or animal drinking trough includes a body 1A. A screw-threaded spigot (to retain a mounting nut) preferably forms one end section of the body 1A to provide an inlet 2. The other end section of the body 1A is of an increased diameter to form a cavity open at that end. A removable end cap 1B is located in the cavity end of the body 1A to enclose the cavity within the valve. The inner end of the inlet 2 terminates with an annular wall 5 extending into the cavity. The body 1A and end cap 1B are preferably joined by engaging screw-threads IE provided on each. The body 1A also includes a spigot IF extending radially outward from a portion of the wall thereof surrounding the inner inlet wall 5 to form an outlet 3 for the valve.

A flexible member 10 is mounted within the cavity and separates the inlet 2 from the end cap 1B to form a back-pressure chamber 4 (inlet 2 being connected to chamber 4 as described below) between the flexible member 10 and the end cap IB. The inner end of the wall 5 forms a valve seat 6 against which the flexible member 10 seats, the flexible member 10 also separating (providing for opening and closing of the valve) the inlet 2 from the outlet 3, both these functions being described in more detail below.

ON2303NZA_Amnd_CompSpec_13Aug20U_EHB.doc An actuator arm 7 is pivotally mounted at an inner end thereof to end cap IB. In known manner, a float (not depicted) can be attachable to the outer end of arm 7 to provide for the raising and lowering thereof. Alternatively, rather than a float a "near neutral buoyancy weight" as described in out NZ patent 535912 can be attached thereto. Arm 7 reciprocally operates, if the near neutral buoyancy weight is used, the arm 7 requires a spring 7A (see figures 1 and 2) to raise the arm, a valve opening and closing control pin 8 mounted in an associated bleed passage 9 formed longitudinally through a control pin 8 mounting 16.

Mounting 16 is mounted to an inner central section of the housing 1B and extends therefrom to project through the flexible member 10. The flexible member 10 is preferably in the form of a diaphragm as described in more detail below. The surface area of the diaphragm 10 presented to the chamber 4 is larger than that surface area thereof presented to the inlet 2.

The bleed passage 9 joins the inlet 2 to the chamber 4 to thus provide the "back-pressure" within the chamber 4. The bleed passage 9 also vents the chamber 4 to enable the valve to close and open respectively. To that end the pin 8 by being connected to the actuator arm 7 is slid back and forth within the bleed passage 9 with raising and lowering of the actuator arm 7. More particularly a pair of longitudinally spaced apart seals 15, preferably "0"-rings, are mounted in the bleed passage 9 to seal about the pin 8. The pin 8 includes a pair of longitidinally spaced apart grooves 17, the spacing of the grooves 17 being complementary to the spacing of the seals 15. In the closed mode a first of the seals 15A is bridged by a first of the grooves 17A to join the inlet 2 to the chamber 4. Also the second groove 17B is disposed clear of the second seal 15B which closes the vent section of the bleed passage 9 from the chamber 4. In an open mode the first groove 17A is disposed clear of the first seal 15A to close the bleed passage 9 between the inlet 2 and the chamber 4 and the second groove 17B is disposed to bridge the second seal 15B to vent the chamber 4.

Thus, in a first mode (float arm 7 raised) the bleed passage 9 connects the chamber 4 to the inlet 2 and, owing to the larger surface area of the diaphragm 10 presented to the chamber 4, the diaphragm 10 displaces toward the valve seat 6 and closes there against. In that mode the venting of the chamber 4 is closed. In a second mode (aim 7 lowered) the bleed passage 9 vents the chamber 4 thus enabling the diaphragm 10 to displace away from the valve seat 6 and the valve to open.

The diaphragm 10 is preferably dish shaped having a central section 10A surrounded by an annular wall section 1 OB disposed substantially normal or uprightly to the central section 10A. The thickness of the diaphragm 10 is preferably enlarged at the comer junction of the ON2303NZA_Amnd_CompSpec_13Aug2014_EHB.doc two sections 10A and 1 OB and the inlet 2 associated face of the diaphragm 10 at that comer junction forms a seal 1 OF for the valve. Seal 1 OF impinges against the valve seat 6 to close the valve. The diaphragm 10 is retained about its periphery preferably between abutting shoulders 1C and ID provided on each of the housing parts 1A andlB adjacent the screw- threaded junction IE therebetween. Preferably, as more clearly depicted in Fig 1, the shoulders 1C and ID are longitudinally spaced from the valve seat 6 an amount commensurate to the extent of dishing of the diaphragm 10 provided by the annular wall section 1 OB thereof. Preferably the peripheral rim of the diaphragm 10 includes an upstanding rib 10G which is compressed between the shoulders 1C and ID with the mounting of the end cap 1B to the body 1A.

Between the annular wall section 1 OB and the peripheral rim/rib 10G of the diaphragm 10 an intermediate flexing section 10C is provided. Preferably diaphragm section 10C includes an annularly disposed wave formation lOd that facilitates the diaphragms longitudinal flexing and displacement with opening of the valve to the "open" position depicted in Fig 2. As aforesaid, the pin mounting 16 extends through the diaphragm 10, the pin mounting 16 preferably including an annular channel 16A in which a central tubular wall section 10E of the diaphragm 10 sealingly located and anchored. Also, referring in particular to Fig 1, in the closed mode preferably the central section 10A is marginally conically formed to anchor the central wall section 10E forward, relative to the displacement movement of the diaphragm 10, of the seal 1 OF thereof.

A slide 12 is coupled to the annular wall section 1 OB of the diaphragm 10 as to be displaced therewith. Preferably the slide 12 is annularly shaped having an outer longitudinally extending wall 12D with an inwardly extending shoulder 12B, preferably of an increased wall thickness, at a forward end thereof. The wall 12D of the slide 12 is a sliding fit within the inner face or bore 1G of the section of the body 1A forming the cavity of the valve. A rebate 12A is formed in the inner wall 12D of wall 12B to form an annular inwardly disposed lip 12C. The annular wall section 10B of the diaphragm 10 includes an outwardly disposed enlargement 1 OH forming a shoulder 13, the enlargement 1 OH locating in the rebate 12A of the slide 12 with the lip 12C fitting over shoulder 13 to couple the diaphragm 10 and slide 12 together.

A section of wall 12D is spaced radially outward of and, in the closed mode, extends around the inner wall 5 of the inlet 1. The 'closing" travel of the slide 12 is limited by a stop 11 ON2303NZA_Amnd_CompSpec_13Aug2014_EHB.doc provided by the shoulder 14 formed on the face or bore 1G of the body IB. With closing of the valve, as the seal 10F impinges on the valve seat 6, the associated end of the slide 12 abuts the shoulder 14 to prevent further closing travel of the slide 12. Preferably the stop 11 comes into play just before complete seating of the seal 1 OF on seat 6 takes place, full closure requiring some minimal compression of the diaphragm 10 against the seat 6. Thus the slide 12 prevents undue distortion of the diaphragm 10 particularly once the valve has fully closed. Referring to Fig 2, the longitudinal spacing of seat 6 relative to the outlet 3 and the length of the slide 12 provide that, with displacement of the diaphragm 10 to the fully open mode, the slide 12 is spaced clear of the outlet 3 and thus presents little or no impediment to the liquid flow through the valve.

To those skilled in the art to which the invention relates, many changes in construction and widely differing embodiments and application of the invention will suggest themselves without departing from the scope of the invention as defined in the appended claims. The disclosures and the descriptions herein are purely illustrative and are not intended to be limiting.

For purposes of the description hereinafter, the terms "upper", "lower", "right", "left", "vertical", "horizontal", "top", "bottom", "lateral", "longiWinal" and derivatives thereof shall relate to the invention as it is oriented in the drawing figures. However it is to be understood that the invention may assume various alternative variations, except where expressly specified to the contrary. It is also to be understood that the specific devices illustrated in the attached drawings, and described in the following specification are simply exemplary embodiments of the invention. Hence specific dimensions and other physical characteristics related to the embodiments disclosed herein are not to be considered as limiting.

Advantages a) Modest cost b) Few parts c) Simple assembly d) Diaphragm is supported when the valve is closed to prevent it from being damaged e) High flow rate is possible as the seal supporting piece is pulled back with the diaphragm and does not restrict the flow ON2303NZA_Amnd_CompSpea3Aug2014_EHB.doc f) Valve body is protected from over pressure Variations Throughout the description of this specification, the word "comprise" and variations of that word such as "comprising" and "comprises", are not intended to exclude other additives, components, integers or steps. It will also be understood that where a product, method or process as herein described or claimed and that is sold incomplete, as individual components, or as a "kit of Parts", that such exploitation will fall within the ambit of the invention.

It will of course be realised that while the foregoing has been given by way of illustrative example of this invention, all such and other modifications and variations thereto as would be apparent to persons skilled in the art are deemed to fall within the broad scope and ambit of this invention as is hereinbefore described.

These and other features and characteristics of the present invention, as well as the method of operation and functions of the related elements of structures and the combination of parts and economics of manufacture, will become more apparent upon consideration of the following description with reference to the accompanying drawings, all of which form part of this specification, wherein like reference numerals designate corresponding parts in the various figures.

ON2303NZA_Amnd_CompSpec_13Aug2014_EHB.doc

Claims (9)

What we claim is;

1. A liquid pressure control valve including a body forming a cavity and incorporating an inlet port and an outlet port joining to the cavity, forming a flow path for a liquid there through, a flexible member retained within the cavity to extend over the inlet port to 5 separate the inlet port from the outlet port and to also form a chamber separated from the outlet port, a controlled bleed passage joining the inlet to the chamber, other than in an open position of the valve, whereby inlet pressure in the chamber will displace the flexible member toward a closed position with a seal of the flexible member seated over the inlet port, with in the open position the bleed passage venting the chamber, 10 characterised in that a slide is mounted within the cavity and is coupled to a section of the flexible member surrounding the seal of the inlet port thereof as to be displaced with displacement of the flexible member, and a stop to prevent closing displacement of the slide after the flexible member has seated and sealed over the inlet port in the closed position, wherein the flexible member is in the form of a diaphragm with a the body 15 retaining an outer peripheral section of the diaphragm, the diaphragm including a central dished section surrounded by an annular wall section disposed substantially normal to the central dished section with a junction of these two sections forming the seal, the slide being coupled to the annular wall section of the diaphragm to enable the diaphragm with the slide to move out of the flow path to achieve maximum fluid flow through the valve. 20

2. A valve as claimed in claim 1 wherein the valve seat is spaced radially inward and also longitudinally of the outer periphery of the diaphragm with the longitudinal spacing being commensurate to the depth of the dishing of the central section of the diaphragm.

3. A valve as claimed in claim 2 wherein a section of the diaphragm adjacent to the peripheral section thereof incorporates at least one annulariy disposed wave formation to 25 facilitate longitudinal displacement of the central section of the diaphragm.

4. A valve as claimed in any one of the preceding claims adapted to be operated by either a float or a near neutral buoyancy weight connected to an actuator arm pivotally mounted to the body to reciprocally operate a pin, the pin including a pair of longitudinally spaced apart grooves, mounted in the bleed passage between a valve open mode and a valve 30 closed mode, to that end the bleed passage including a pair of complementary longihidinally spaced apart seals to seal against the pin, whereby in the closed mode a ON2303NZA_Amnd_CompSpec_13Aug2014_EHB.doc first of the seals is bridged by a first of the grooves to join the inlet to the chamber and the second groove is disposed clear of the second seal which thus closes a vent from the chamber and, in an open mode, the first groove is disposed clear of the first seal to close the bleed passage between the inlet and the chamber and the second groove is disposed to 5 bridge the second seal to vent the chamber.

5. A valve as claimed in any one of the preceding claims wherein the inlet terminates with an annular wall extending into the cavity with the inner end thereof forming the valve seat and the surrounding section of the cavity wall forms a bore, the slide being annularly shaped to surround the inner wall and be a working fit within the bore. 10

6. A valve as claimed in claim 5 wherein the slide includes an inwardly extending annular shoulder at a forward end thereof, the inner wall of the shoulder including a rebate in which an enlargement on the diaphragm locates to couple the slide and diaphragm together.

7. A valve as claimed in claim 5 or claim 6 wherein the longitudinal spacing of seat relative 15 to the outlet and the length of the slide provide that, with displacement of the diaphragm to the fully open mode, the slide is spaced clear of the outlet.

8. A valve as claimed in any one of the preceding claims wherein the stop is disposed to come into play just before complete closure of the valve, full closure requiring some minimal compression of the diaphragm. 20

9. A valve substantially as herein described with reference to the accompanying drawings. PIPERS Attorneys for the Applicant