AU685407B2 - Pressure reducing valve - Google Patents

Description

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AUSTRALIA

Patents Act 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT Name of Applicant(s): Actual Inventor(s): Address for Service: COBRA WATERTECfI (PROPRIETA LIMITED

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SEC.

GONTHER FRIEDRICH WISSER \U AVRON FULLERTON 0 CULLEN CO., Patent Trade Mark Attorneys, 240 Queen Street, Brisbane, Qld. 4000, Australia.

Invention Title: PRESSURE REDUCING VALVE St

SOS.

5005 0* a The following statement is a full description of this invention, including the best method of performing it known to us: d Ip4 THIS INVENTION relates to a pressure reducing valve.

This invention relates especially, but not exclusively, to pressure reducing valves for water reticulation systems for dwellings or other buildings, which pressure reducing valves provide water at a desired working pressure.

The function of a pressure reducing valve is to reduce the pressure of a fluid supplied to the valve at a pressure higher 0 than a set pre-determined pressure, to said pre-determined pressure. For convenience, for purposes of this specification, "supply pressure" shall mean the pressure at which fluid is supplied to the valve, "set pressure" shall mean the maximum pressure at which the fluid is desired to be delivered, and "reduced pressure" shall mean the pressure at which fluid is delivered by the valve.

According to a first aspect of this invention there is provided a pressure reducing valve adapted to receive fluid at a relatively high supply pressure and to deliver the fluid at a reduced pressure which is not more than a relatively low set pressure, the pressure reducing valve comprising: a housing having an inlet via which fluid is received in use and an outlet via which fluid is delivered in use; means defining a fluid flow path between said inlet and said outlet; a closure member associated with said fluid flow path and being displaceable between a closed position in which it closes off said fluid flow path and an open position in which it permits flow along said fluid flow path; biassing means engaged with said closure member for biassing said closure member towards the open position; control means responsive to the reduced pressure to dominate the biassing means when the reduced pressure is at lea'st equal to the set pressure to displace the closure member to 0 its closed position, and to submit to the biassing means when the reduced pressure is lower than the set pressure to allow the biassing means to displace the closure member to its open position; and adjusting means for adjusting the biassing means to adjust the set pressure, the adjusting means being adjustable in discrete steps predetermined to correspond to a plurality of predetermined set pressures.

-4C ~IPI~ The biassing means may be resilient and may comprise a spring arranged to act in compression between a first abutting surface and a second abutting surface connected to said closure member.

The adjusting means may include means for adjusting the spacing between the first and second abutting surfaces. The position of the first abutting surface may be adjustable. Check means may be provided to check the first abutting surface in any one of a plurality of predetermined positions.

In a preferred embodiment, the biassing means may include a cylinder within which the spring is received, and the adjusting means may include a sleeve assembly slidable over the cylinder, the first abutting surface being connected to the sleeve assembly such that the position of the sleeve assembly determines the :position of the first abutting surface. Adjusting nay then be effected by adjusting the sleeve assembly. The check means may include a transverse formation such as a pin or lug fast with one of the cylinder and the sleeve assembly, and complemental gates and notches in the other of the cylinder and the sleeve assembly to enable the pin or lug to be located in a desired notch or S stop, each notch or stop representing a different position for the first abutting surface and thus a different pre-determined set pressure.

S:o Releasable locking means may be provided for holding said first abutting surface and said second abutting surface in a plurality I -L of substantially fixed spaced relationships, each said fixed spaced relationship corresponding to one of said plurality of discrete pressure settings. In the preferred embodiment, the locking means may include a clamping screw arranged to clamp the cylinder and the sleeve assembly to prevent tampering or inadvertent adjustment.

Advantageously said plurality of discrete pressure settings may include 100kPa, 200kPa and 400kPa system pressure settings.

Indicating means may be provided on said valve for indicating at which discrete pressure setting the valve has been set.

The indicating means may include markings on the cylinder corresponding to the different discrete pressure settings, each marking corresponding to one of said pressure settings and being arranged to align with an end of the sleeve when the valve is set at that respective pressure setting.

The indicating means may include different colour codes for the different markings.

S. The valve may include receiving means for receiving a pressure relief valve, downstream of said closure member. Said receiving '25 means, may be located adjacent said closure member and may be integral with or assembled with said housing, e.g. in the form of a screw threaded socket, or with a cap nut connection to enable easy positioning-of the relief valve outlet. Instead, the 6 receiving means may be in the form of connecting means for connecting a separate pressure relief valve with the pressure reducing valve. In practice, the pressure rating of the pressure relief valve will correspond with the pressure setting of the valve.

An embodiment of the invention will now be described by way of example, with reference to the accompanying diagrammatic drawings, in which: Figure 1 shows, in axial section, a pressure reducing valve in accordance with the invention; Figure 2 is an end view taken at II in Figure 1; Figure 3 is a top plan view of the pressure reducing valve of Figure 1; and Figure 4 corresponds to Figure 1 but shows another embodiment.

With reference to Figures 1 to 3 of the drawings, a pressure" S. reducing valve in accordance with the invention is generally indicated by reference numeral The pressure reducing valve comprising a body 12 which is of cast S or moulded construction and which includes a central cup 14 having a rim 16 and a sump 18. Its axis is indicated at Diametrically opposed branches, more specifically an inlet branch and an outlet branch 22, extend from the central cup 14. A S cartridge which is of generally round cylindrical form and is indicated generally by reference numeral 24 is partially, co- 7 axially, receivable within the central cup 14.

The inlet branch 20 provides an inlet 26 to which an inlet pipe 27 is shown to be connected. Immediately downstream of the inlet 26, within the inlet branch 20, there is provided a non-return val'e assembly generally indicated by reference numeral 28. The inlet 26 is, for ease of installation of the pressure reducing valve 20, adapted for connection to a pipe such as the pipe 27 by means of pipe threads or collars and ferrules. Thus, for the latter, the socket has an external screw thread and chamfered mouth.

The outlet branch 22 provides an outlet assembly 30 in the form of a cap nut connection to facilitate orientation of an outlet body and relief valve to be described with reference to Figure 3.

An internal flow path is defined within the pressure reducing valve extending from the inlet 26 via internal structure of the "0 central cup 14 and structure of the cartridge 24 to the outlet S' The central cup 14 has a roof 32 at a level below its rim 16.

It further has an intermediate floor 34 intermediate the roof 32 and the sump 18. A chamber 38 is defined in the cup 14 intermediate the floor 34 and roof 32. Round openings are provided both in the roof 32 and the intermediate floor 34 to receive a foot 36 of the cartridge 24 and which is of generally L 8 round cylindrical form. A division wall 35 connects the intermediate floor 34 to the roof 32 separating the downstream from the upstream side.

A passage 48 aligned with the inlet branch 20 is defined between the roof 32 and the intermediate floor 34. The passage 48 extends to the division wall 35 and communicates with the chamber 38.

An interrupted, peripheral inlet 40 is provided through the foot 36. In series with and co-axial with the foot 36, there is provided a skirt 42 extending downwardly from the intermediate floor 34. The skirt 42 is open bottomed as shown at 44 and defines a circumferential valve seat 46 at its lower end.

The foot 36 and skirt 42 will be stationary in use.

The cartridge 24 comprises, towards its end projecting into tie central cup 14, a stem 50 anchored in internal structure of the cartridge and which is axially displaceable as indicated by reference numeral 54. At an outer end of the stem 50, there is provided a closure 52 having a circumferential gasket aligned with the circumferential seat 46. In use, when the stem 50 and closure 52 are moved in one direction, it opens the open bottom 25 44 of'the stationary skirt 42. This is the condition illustrated in Figure 1. It can be displaced such that the closure 52 seats against the circumferential seat 46 to close the open bottom 44.

9 The flow path referred to above is thus provided via the inlet 26, the non-return valve assembly 28, the passage 48, the chamber 38, the peripheral inlet 40, the skirt 42 and the open bottom 44 into the sump portion of the central cup f:-i where it continues via the outlet branch 22 and the outlet 30. When the closure 52 is in its closed condition, the flow path is closed.

The cartridge 24 comprises a stationary cyli-, .r 56 which is mounted within the rim 16 of the central cup e.g. screw threadingly as shown, or by means of a nut abutting a shoulder on the cylinder 56 and engaging an external screw thread on the rim 16. The structure of the cartridge described above is mounted on the cylinder 56.

A coil spring 58 mounted for compression co-axially within the cylinder 56 abuts an annular seat member 60 which forms a second abutting surface in accordance with the invention. The annular seat member 60 is floating and is abuttingly connected to the internal core structure referred to above and thus also to the 0 stem 50. Thus, the spring 58, acting in compression, biasses the closure 52 to its open position.

The cartridge 24 further comprises an inverted cup 62 having a Oo sleeve 64 fitting snugly, slidably over the cylinder 56. It has 5 a cenitral boss 66 fixed to its bottom by means of a screw 68.

The central boss 66 extends into the cylinder 56 via an aperture o 70 in a top of the cylinder 56. These structural members form a sleeve assembly in accordance with the invention.

~EPd\Y 13L~ YP~ 4Br( C~sp~ At the free end of the central boss 66, there is provided a seat member 72 providing a first abutting surface in accordance with the invention. An end of the spring 58 opposed to the end seated in the annular seat member 60, is seated in the seat member 72.

Above the seat member 72, there is provided a diametrical aperture 76 through the boss 66. A transverse pin 74 is fixedly mounted within the aperture 76 such that at least one end, or both ends as in this embodiment, extend laterally to form projections 78. These projections may instead be formed by means of an integral lug or lugs on the outer circumference of the cylinder 56 or internally in the sleeve 64.

The projections 78 are slidably received within check means provided in the cylinder 56 or in the inverted cup 62 and which are generally indicated by reference numeral 80 in Figure 2.

Each of the check means 80 comprises a longitudinal channel -8 and two transverse notches or projections respectively 86 and 88 provided at predetermined, longitudinally spaced positions.

An end 84 of the longitudinal channel serves the same function as the notches, namely to locate the projection 78 in a desired, predetermined position. The projections 78 are shown received within the notches 88.

Rotational movement and axial displacement of the inverted cup 62 allow the projections 78 to be displaced from the previously occupied notches and to be inserted into desired other notches.

11 Such manipulating adjusts the spacing between the first abutting surface provided by the seat member 72 and the second abutting surface provided by the seat member 60, which in turn adjusts the axial length of the spring 58 and thus its tension.

Locking means is provided by means of a transverse socket provided in the sleeve 64 toward a free end thereof, in combination with a clamping screw 92 received within the socket When the inverted cup 62 has been adjusted to a desirel position as described above, the clamping screw 92 is operated to clamp the inverted cup 62 against the cylinder 56 to retain it in the adjusted or set condition. A cover 93 is provided to cover the head of the screw 92. The head has a specially designed a-circular engagement formation as shown schematically at 95. A special tool is issued to authorized personnel only to adjust the valve. Tampering is thus prevented.

With reference to Figure 2, indicating means is provided in the form of peripheral rings, respectively 94, 96 and 98 on the :"20 cylinder 56. The rings are positioned in relation to the check means 80 such that one of the rings is exposed immediately below an end 100 of the inverted cup 62. The specific pair of notches in which the projections are located, dictates which of the rings will be exposed, which is indicative of the prevailing spring *25 pressure. Each of the rings 94, 96, 98 is coloured differently representing a desired pressure setting for the pressure reducing valve 12 In use, the closure 52 is responsive to the reduced pressure in the outlet blanch 22 and immediately upstream thereof. If that reduced pressure rises to a predetermined, set pressure, the closure 52 is displaced upwardly againrL the bias of the spring 58 to close the open end 44 and thus to interrupt flow through the flow passage, thus creating the reduced pressure in use.

When the reduced pressure falls below the predetermined set pressure, the biassing means, i.e. the spring pressure, dominates and displaces the closure 52 to unseat from the circumferentia? seat 46 and ti~us to reestablish the flow path through the pressure reducing valve With reference more specifically to Figure 3, by way of development, a lateral or vertical outlet 102 is provided on an outlet body 101 connected to the branch 22 by means of the cap nut 30. The lateral or vertical outlet 102 provides receiving means in accordance with the invention for a pressure relief valve 104 having an outlet provided by an outlet socket 106. -Ii" use, the rating of the pressure relief valve 104 will correspond to the set pressure of the pressure reducing valve It is a first advantage of the pressure reducing valve 10 that its pressure setting can easily be adjusted to one of a plurality of possible values, for example 100 kPa, 200 kPa, 400 kPa system pressure. It is a further advantage that the valve can be locked in a set adjusted position. It is a third advantage that the setting can easily be determined by referring to the colour of the ring 94, 96, 98 exposed immediately below the inverted cup

I

62. It is yet a further advantage that a pressure relief valve can be mounted on the casing or body of the pressure reducing valve 10. By having an outlet body, which is connected by means of the cap nut 30 to the outlet 30, versatility in installation configurations is attained.

It is an important advantage that the pressure reducing valve is pre-calibrated and can be adjusted to alter its setting without having to test the pressure and readjust the valve to obtain a desired, known, setting.

With reference to Figure 4, a further embodiment of a pressure reducing valve in accordance with the invention is generally indicated by reference numeral 110. The features of the pressure reducing valves 10 and 110 in accordance with this invention are very similar, and are not again described. For purposes of disclosing the best way currently known to the Applicant to perform the invention, features and components of the pressure reducing valve 110 and which do not directly relate to the inventive features are now described. Generally, the alternative features of the Figure 4 embodiment perform the same function and are structured similarly to corresponding features of the Figure 1 embodiment. Thus, for convenience, similar reference numerals are used to denote similar features or components. Also the Figuie 4 embodiment will not be described in detail but merely generally with reference to Figure 4 which shows the alternative embodiment in detail.

The pressure reducing valve 110 has a body 112 of cast construction which includes an upwardly extending rim portion 116 having internal screw threading within which the cartridge 124 is screw threadingly received.

The valve body 112 includes an inlet branch 120 for connection to a pipe supplying water under supply pressure to the pressure reducing valve 110, and an outlet branch 122 delivering water at reduced pressure to a domestic or other reticulation system requiring the water to be delivered at the reduced pressure i.e.

at a pressure not exceeding a predetermined set pressure.

The inlet branch 120 leads into an annular chamber 138 provided around a strainer 128 via which the water can flow into an inner chamber and thence downwardly via an open end 144 of an insert 142 defining at a lower end thereof a seat 146. Thence, the water flows via peripheral ports 141 into an outlet chamber 149 in communication with the outlet branch 122.

O A stem 150 depends from a floating diaphragm assembly generally indicated by reference numeral 160, through the inner chamber within the strainer 128 and through the open end 144 of the insert 146. At a lower end of the stem 150, it carries a closure assembly 152 having an upwardly exposed gasket which can sealingly seat on the seat 146 at a lower end of the insert 142.

As was described with reference to Figure 1, biassing means forming part of the cartridge 124 biasses the diaphragm assembly 160 and thus with it also the stem 150 and the closure assembly 152 downwardly i.e. into an open position to allow liquid such as water to flow from the inner chamber within the strainer 128 via the open end 144 of the insert 142 and via the ports 141 into the outlet chamber 149.

The outlet chamber 149 is in communication with a volume in the vicinity of the floating diaphragm assembly 160 to expose the underside of a diaphragm 139 to the pressure prevailing in the outlet chamber 149. As was described with reference to Figure 1, and in accordance with the invention, the cartridge 124 and specifically the biassing means is adjusted in correspondence with a predetermined set pressure. If the pressure in the outlet chamber 149 is lower than the predetermined set pressure, the biassing means prevails and keeps the closure assembly 152 in its open condition to allow water to flow through the pressure reducing valve 110. However, when the prevailing :ressure in the outlet chamber 149 rises to said predetermined set pressure,-i1E dominates the biassing means via the membrane 139 and displaces the diaphragm assembly -60 upwardly against the biassing means thus taking the stem 150 and the closure assembly 152 therewith such that the gasket of the closure assembly seals on the seat 146 of the insert 142 thus to stop or terminate flow of liquid through the pressure reducing valve 110.

i *fee Thus, in a manner similar to what was described with reference to Figure 1, the pressure reducing valve 110 regulates the .o pressure in the outlet chamber 149 to a value not more than the -s 16 predetermined set pressure to supply water at the reduced pressure via the outlet branch 122 to the reticulation system.

It is emphasized that the cartridge 124 and the other features in accordance with this invention operate in substantially identical manner as was described with reference to Figure 1.

The outlet branch 122 is connected via a connecting tube 208 and a pair of compression joints 210 to a T-piece 201 having an outlet 130 to the reticulation system. In the branch 202 of the T-piece 201, there is provided a pressure relief valve 204 which will be set at a pressure corresponding to, i.e. only slightly higher than, said predetermined set pressure. The pressure relief valve 204 has an outlet 206 which can be connected to an exhaust. The function and operation of the pressure relief valve T 204 is virtually identical to those described with reference to S the Figure 1 embodiment.

The embodiment of Figure 4 has generally the same advantages- as were described for the Figure 1 embodiment. In addition, because the pressure relief valve 204 is not integrally coupled thereto, it allows more freedom of choice in that regard.

Claims (10)

1. 2. A pressure reducing valve as claimed in Claim 1 in which the biassing means comprises a spring arranged to act in compression between the first abutting surface and the second abutting surface, in which the second abutting surface is *zopnnected to said closure member, .In which the position of the 19 first abutting surface is adjustable, and which includes check means to check the first abutting surface in any one of a plurality of predetermined positions which correspond respectively to said plurality of predetermined spacings between the first abutting surface and the second abutting surface.
2. 3. A pressure reducing valve as claimed in Claim 2 in which the biassing means includes a cylinder within which said spring is received, and in which the adjusting means includes a sleeve assembly slidable over the cylinder, the first abutting surface being connected to the sleeve assembly such that the position of the sleeve assembly determines the position of the first abutting surface, and in which adjusting is effected by adjusting the sleeve assembly. C.
3. 4. A pressure reducing valve as claimed in Claim 3 in which the check means includes a transverse formation fast with one of the cylinder and the sleeve assembly, and complemental gates and notches or stops in the other of the cylinder and the sleeve assembly to enable the transverse formation to be located S in a desired notch or stop, each notch or stop representing a different one of said plurality of predetermined positions for the first abutting surface and thus a different predetermined set pressure. A pressure reducing valve as claimed in Claim 4 which includes releasable kocking means provided for the purpose of holding said first abutting surface and said second abutting surface selectively in one of said plurality of predetermined spacings.
4. 6. A pressure reducing valve as claimed in Claim 5 in which said releasable locking means includes a clamping screw arranged to clamp the cylinder and the sleeve assembly to prevent tampering or inadvertent adjustment.
5. 7. A pressure reducing valve as claimed in Claim 4, Claim or Claim 6 in which said plurality of discrete pressure settings includes 1OOkPa, 200kPa and 400kPa system pressure settings. W 8. A pressure reducing valve as claimed in Claim 7 which includes indicating means provided on said valve for indicating at which discrete pressure setting the valve has been set.
6. 9. A pressure reducing valve as claimed in Claim 8 in which the indicating means includes markings on the cylinder 9 corresponding to the different discrete pressure settings, each marking corresponding to one of said pressure settings and being arranged to align with an end of the sleeve when the valve is set at that respective pressure setting. A pressure reducing valve as claimed in Claim 8 or Claim 9 in which the indicating means includes different colour codes for the different markings. 21
7. 11. A pressure reducing valve as claimed in any one of the preceaing claims which includes receiving mea%:s for receiving a pressure relief valve, downstream of said closure member.
8. 12. A pressure reducing valve as claimed in Claim 11 in which said receiving means is located adjacent said closure member and is integral with or assembled with said housing.
9. 13. A pressure reducing valve as claimed in Claim 11 in which said receiving means is in the form of connecting means for connecting a separate pressure relief valve with the pressure reducing valve. DATED this 2nd day of October 1997 COBRA BRANDS (PROPIRETARY) LIMITED 0 By their Patent Attorneys CULLEN CO. o* o a c o* ABSTRACT A pressure reducing valve 10 has an inlet 20 for receiving a fluid at supply pressure and an outlet 22 for delivering the fluid at a reduced pressure which does not increase beyond a predetermined set pressure. A cartridge 24 has a biassing spring 58 biassing a closure assembly 52 to an open condition. Fluid pressure in an outlet chamber, when it rises to the predetermined set pressure, overrides the biassing force via a pressurized membrane to close the valve. The biassing spring can be adjusted to predetermined, discrete, set pressures. Adjusting is via a sleeve 64 slidable over a cylinder 56 accommodating the spring
10. 58. A transverse pin 74 fixed to the cylinder can be checked in various notches in the sleeve corresponding to the various settings. 6 a o9 e. 9 o*