US3926211A - Fluid flow control valve - Google Patents

Fluid flow control valve Download PDF

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Publication number
US3926211A
US3926211A US467100A US46710074A US3926211A US 3926211 A US3926211 A US 3926211A US 467100 A US467100 A US 467100A US 46710074 A US46710074 A US 46710074A US 3926211 A US3926211 A US 3926211A
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US
United States
Prior art keywords
valve
outlet
pressure
chamber
area
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US467100A
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English (en)
Inventor
Bernard Graham Maclarty
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Phoenix Valve Manufacturers Ltd
Zimco Industries Pty Ltd
Original Assignee
Phoenix Valve Manufacturers Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Phoenix Valve Manufacturers Ltd filed Critical Phoenix Valve Manufacturers Ltd
Application granted granted Critical
Publication of US3926211A publication Critical patent/US3926211A/en
Assigned to DUTTON PLASTICS ENGINEERING (PTY) LTD., A CORP. OF SOUTH AFRICA reassignment DUTTON PLASTICS ENGINEERING (PTY) LTD., A CORP. OF SOUTH AFRICA ASSIGNMENT OF ASSIGNORS INTEREST. Assignors: AECI LIMITED A CORP. OF SOUTH AFRICA
Assigned to COOKSON (SA) (PROPRIETARY) LIMITED, 5TH FLOOR, SANDTON CITY, CNR. RIVONIA ROAD AND 5TH STREET, SANDTON, TRANSVAAL PROVINCE, REP. OF SOUTH AFRICA reassignment COOKSON (SA) (PROPRIETARY) LIMITED, 5TH FLOOR, SANDTON CITY, CNR. RIVONIA ROAD AND 5TH STREET, SANDTON, TRANSVAAL PROVINCE, REP. OF SOUTH AFRICA ASSIGNMENT OF ASSIGNORS INTEREST. Assignors: DUTTON PLASTICS ENGINEERING (PROPRIETARY) LIMITED
Assigned to ZIMCO INDUSTRIES (PTY) LTD reassignment ZIMCO INDUSTRIES (PTY) LTD CHANGE OF NAME (SEE DOCUMENT FOR DETAILS). EFFECTIVE DATE: MARCH 16, 1989 SOUTH AFRICA Assignors: COOKSON (SA) (PROPRIETARY) LIMITED
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16K—VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
    • F16K31/00—Actuating devices; Operating means; Releasing devices
    • F16K31/12—Actuating devices; Operating means; Releasing devices actuated by fluid
    • F16K31/36—Actuating devices; Operating means; Releasing devices actuated by fluid in which fluid from the circuit is constantly supplied to the fluid motor
    • F16K31/365—Actuating devices; Operating means; Releasing devices actuated by fluid in which fluid from the circuit is constantly supplied to the fluid motor the fluid acting on a diaphragm
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T137/00—Fluid handling
    • Y10T137/7722—Line condition change responsive valves
    • Y10T137/7781—With separate connected fluid reactor surface
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T137/00—Fluid handling
    • Y10T137/7722—Line condition change responsive valves
    • Y10T137/7781—With separate connected fluid reactor surface
    • Y10T137/7793—With opening bias [e.g., pressure regulator]
    • Y10T137/7801—Balanced valve
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T137/00—Fluid handling
    • Y10T137/7722—Line condition change responsive valves
    • Y10T137/7781—With separate connected fluid reactor surface
    • Y10T137/7793—With opening bias [e.g., pressure regulator]
    • Y10T137/7808—Apertured reactor surface surrounds flow line

Definitions

  • ABSTRACT A fluid flow control valve is disclosed in which the [21] Appl. No. 467,100 movable element of the valve is in the form of a spool mounted in a casing by means of two rolling dia- [30] Foreign Application Priority Data phragms.
  • the spool is hollow and a fixed cross-bar May 8,1973 South Africa 73/3118 Passes through one form, the Spool Carries a valve closure member and the outlet is in the centre of 52 s CL 137 94; 75 13750525 the cross-bar.
  • the crossbar carries 51 int. 01 F16K 31/365; F16K 31/385 the Closure member and the valve Outlet is an axial 5 Field f Search 137/494 497, 4842, 4846 bore leading from the hollow interior of the spool.
  • valve inlet leads to the annular chamber defined be- 505 505 5 5 5 5 5 50525 tween the casing, the spool and the diaphragms.
  • the 488 492 4925, 505 251, 282, 496 areas of the end walls of the annular chamber are different to one another and are chosen so that an inlet 5 References Cited pressure derived force acts on the spool to reduce the UNITED STATES PATENTS out of balance forces which act thereon due to the 815 917 3/1906 d 137/505 18 provision of the outlet.
  • FLUID FLOW CONTROL VALVE This invention relates to fluid flow control valves.
  • a fluid flow control valve comprising a casing and a movable valve element in the casing, in which valve the inlet of the valve leads to a chamber bounded externally by said casing and internally by said element, that wall which forms one end of said chamber having an area different to that of the wall which fonns the other end of the chamber, and an outlet from the valve, the difference in area between said end walls being a function of the area of said outlet, and both walls being movable relatively to the casing.
  • a fluid flow control valve comprising a casing, an inlet leading into said casing, a movable valve element in said casing, first and second means sealing between said element and said casing, such means being spaced apart in the direction in which said element is capable of movement and, to gether with said casing and said element, bounding a pressure chamber into which said inlet leads, the valve element having a hollow interior which communicates with said chamber and there being a valve outlet lead ing from said hollow interior, said element having a position in which said outlet is closed and being capable of movement from said position to open the valve, and the area of one end wall of said chamber, over which area the pressure in said chamber is effective, being different to the area of the other end wall of said chamber, over which the pressure in said chamber is effective, and the difference being such as to provide on said element a force tending to reduce the out of balance effect arising from the provision of said outlet.
  • FIG. -l is a vertical section through a pressure reducing valve according to one embodiment of the invention.
  • FIG. 2 is a vertical section through a pressure reducing valve according to another embodiment of the invention.
  • FIG. 3 is a vertical section of the valve of FIG. 1 modified for use as a flushing valve
  • FIG. 4 is a section on line IVIV of FIG. 1; and FIG. 5 is a section on line VV of FIG. 3.
  • reference numeral generally indicates a pressure reducing valve comprising a casing 12 which includes a main part 14 and upper and lower end caps 16 and 18.
  • An inlet structure 20 includes a non-retum ball valve 22, a union 24, and an elbow 26 provided with a filter screen 28. The free end of the elbow 26 is provided with an inlet connection 30.
  • the structure 20 will be described in more detail subsequently.
  • the valve 10 further includes a movable valve element 32 which is supported by a pair of rolling diaphragms 34 and 36.
  • the element 32 is shown in simplified form in FIG. 3.
  • the diaphragms 34 and 36 seal between the element 32 and the casing 12 and are spaced apart in the direction in which the element 32 is capable of moving. Together with the casing 12 and element 32, the diaphragms bound a generally annular pressure chamber 38 into which the inlet 40 formed in the casing 12 2 leads.
  • the element 32 bounds the chamber 38 internally and the casing 12 bounds the chamber 38 externally.
  • the valve element 32 comprises a main part 42 formed with two diametrically opposed slots 44.
  • the upper end 46 of the part 42 is closed and over this end is fitted a retaining ring 48 for the inner periphery of the diaphragm 34 and an internally threaded locking ring 50 for urging the ring 48 into clamping engagement with the diaphragm 34.
  • the rings 48 and 50 can be integral in which case the ring 50 is not threaded but simply fits over the end 46 and secured by swaging.
  • the main part 42 is formed with an externally threaded spigot 52 above which there is a rib 54, the slots 44 dividing the spigot and rib into two arcuate portions.
  • a sealing ring 56 is clamped between the rib 54 and a seat element 58 which is screwed onto the spigot 52.
  • the lower end of the element 58 is externally threaded and a retaining ring 60 for the inner periphery of the diaphragm 36 is fitted over the threaded portion of the element 58.
  • An internally threaded locking ring 62 is threaded onto the element 58 and urges the ring 60 against the diaphragm 36. If the rings 60 and 62 are integral, they would be secured by swaging and not by threading.
  • a cross-member 64 extends across the casing 12 and passes through the slots 44.
  • the member 64 is formed with a core 66 which is within the element 32 and within which is mounted a valve closure member 68.
  • the member 68 co-operates with a seat 70 which encircles the upper end of the valve outlet constituted by a bore 72 in the element 58.
  • the outlet union of the valve is shown at 74 and a spring 76 acts between the end cap 16 and the end 46.
  • the chamber bounded by the end cap 16 can be closed so that air trapped therein acts as a cushion for the element 32.
  • the diameter (D1) of the end cap 16 is less than the diameter (D2) of the end cap 18.
  • the end portions of the element 32 are also of different diameters.
  • the ring 48 is of smaller diameter than the ring 60, these two rings determining the effective diameter of the end walls of the chamber 38 as will be discussed in more detail below.
  • this comprises an externally threaded inlet portion 78 having a bellshaped bore within which there are ribs 80. These ribs prevent the ball 22 from closing-off flow of water into the valve through the structure 20.
  • the elbow 26 includes an external flange 82 over which a locking ring 84, forming part of the union 24, is slipped and threaded onto the portion 78 to hold the elbow in place.
  • a seat element 86 for the ball 22 is located between an internal shoulder of the portion 78 and the holding ring 88 of the filter screen 28 which ring is itself against a shoulder of the elbow 26.
  • the element 86 has a central aperture which the ball 22 enters should water tend to flow from the valve 10 to the elbow 26.
  • the inlet connection 30 comprises a locking ring 90 threaded onto the free end of the elbow 26 and an in ternally threaded spigot 92 held against the elbow 26 by the ring 90.
  • an airtight inlet (not shown) may be provided so that the chamber within the cap 16 may be opened and a liquid, such as water, may be introduced into the chamber whereby the volume of the chamber is reduced.
  • the gas in the reduced volume chamber serves to bias and cushion the element 32 without the use of the spring 76 but can act in conjunction with the spring.
  • the effective area of the end wall constituted by the diaphragm 36 is greater than the effective area of the end wall constituted by diaphragm 34.
  • back pressure at the outlet acts on the element 32 and displaces it, against the action of the spring 76, to the position in which the valve is closed.
  • the force exerted by the spring 76 exceeds that exerted by the back pressure.
  • the element 32 thus moves (downwardly as viewed in FIG. 1) so that the seat element 72 moves away from the member 68;
  • back pressure is recreated and the valve closes.
  • the force exerted by the spring 76 is the main factor in determining the back pressure which must be attained before the valve closes.
  • the inlet pressure to which a valve connected to the mains supply is subjected varies widely during the day as the demand for water rises and falls. By appropriate selection of the relative magnitudes of those areas which are subjected to inlet pressure, it is possible to influence the back pressure required to close the valve.
  • the amount by which said difference in areas can itself differ from the area of the bore 72 depends to some extent on the fluctuations which can be expected in inlet pressure, to some extent on the size of the spring 76 which can be used, and further on the magnitude of the pressure for which the valve is designed. If great variations in inlet pressure or high inlet pressures, are
  • reference numeral generally indicates a pressure reducing valve according to another embodiment of the invention.
  • identical parts of the valves 10 and 100 are denoted by like. reference numerals.
  • valve 100 is similar to the valve 10 except that the valve closure member 68 is now carried by the element 32 and the outlet bore 72 is provided in the crossmember 64.
  • the outlet bore 72 communicates with a transverse passage 102 which leads through the wall of the main casing part 14.
  • a chamber 104 is defined between the cap 18 and the element 32 and a conduit leads from the passage 102 to the chamber 104.
  • the element 32 of this valve is of somewhat simpler construction than that described above and includes a main part 106, in which diametrically opposed slots for receiving the member 64 are provided, and two end caps 108 and 110.
  • the diaphragm 34 is clamped between the part 106 and cap 108, and similarly the dia phragm36 is clamped between the cap 110 and the part 106.
  • the closure member 68 forms part of the cap 110 which is castellated at 1 12 to prevent the chamber 104 being cut-off from the passage 102 when the valve is fully open (as shown).
  • This valve operates in the same manner as valve 10.
  • this valve is a modification of the valve of FIG. 1 and where applicable like parts have been correspondingly referenced.
  • the cross member 64 is at right angles to the inlet 40 and the outlet union 74 is at the upper end of the casing 12 instead of at the lower end.
  • the cap 18 becomes an upper cap and the cap 16 a lower cap which, together with the element, bounds a chamber 114.
  • the chamber 114 is connected by a passage 1 16 to the inlet passage upsteam of the inlet 40 and there is a manually operable e.g. push button, valve 118 in the passage 116.
  • An outlet passage 120 having a flow regulating needle 122 therein leads from the chamber 1 14 to an outlet chamber 124.
  • a spring 126 urges the element to the position in which the valve is closed.
  • the element 32 is diagrammatically shown and comprises a main part 128, closure cap 130 and end rings 132.
  • the upper ring 132 is castellated at 134 to ensure that in the fully open position shown the passage 120 is not cut-off from the chamber 124.
  • the part 128 is formed with slots (running front to rear in the drawing) which place the hollow interior of the element 32 in communication with the pressure chamber which encircles the element 32 and into which the inlet 40 opens.
  • the spring 126 can be omitted and the difference in areas of the ends of the chamber 38 with respect to the area of the bore 72 so chosen that there is on the element 32 an inlet pressure derived force urging the element in the closing direction i.e. against the force exerted by the pressure in the chamber 114.
  • valve element 32 The connection between the hollow interior of the valve element 32 (and which is in communication with the outlet chamber 124 via the bore 124.1 and the inlet 40) is best seen in FIG. 5. It will be noted from this that communication is via the part-cylindrical gap between the parts 14 and 128 and the slots 44.
  • a fluid flow control valve comprising a casing, an inlet leading into said casing, a movable valve element in said casing, first and second means sealing between said element and said casing, such means being spaced apart in the direction in which said element is capable of movement and, together with said casing and said element, bounding a pressure chamber into which said inlet leads, the valve element having a hollow interior and there being an outlet from said hollow interior of the valve element which outlet reduces the area of the movable element on which inlet pressure acts in one direction and which opens into an outlet path leading to the exterior of the valve, said pressure chamber communicating with said outlet path by way of said outlet and said hollow interior, a valve closure member for closing-off said outlet, and said element having a position in which said member closes said outlet to prevent flow from said hollow interior to said outlet path and being capable of movement from said position to establish communication between said hollow interior and said outlet path thereby to open the valve, and the area of one end wall of said chamber, over which area inlet pressure is effective, being different to the area of the other
  • each of said first and second means is constituted by a diaphragm having its inner periphery secured to said element and its outer periphery to said casing.
  • a valve according to claim 1 in which said outlet is constituted by a bore formed in said element and extending from said hollow interior in the direction in which the element is capable of movement.
  • a valve according to claim 3 in which said element includes diametrically opposed slots and a fixed cross-member extends through the element by way of the slots, there being a valve closure member carried by said cross-member and cooperating with said outlet.
  • a valve according to claim 1 in which said element includes diametrically opposed slots and a fixed cross-member extends through the element by way of the slots, said outlet being constituted by a passage in said cross-member and there being a valve closure member carried by said element for closing-off communication between said passage and said hollow interior.
  • a valve according to claim 1 in which said outlet has an area such that said difference in areas is more or less than said area of said outlet whereby a force de rived from inlet pressure is exerted on said element which force varies with inlet pressure.
  • a valve according to claim 1 in which one face of said element is in communication with said outlet so that the element is subjected to back pressure at said outlet and a further face of said element is subjected to a force opposing the force exerted thereon by the back pressure.
  • a valve according to claim 8 and including a coil spring for exerting the opposing force.
  • a valve according to claim 1 comprising spring means for exerting on said element a force tending to move it to the closed position, and a chamber the pressure in which exerts a force tending to move the element to the open position, an inlet to said chamber, a valve for temporarily connecting this chamber to a source of pressure fluid, and a bleed passage from said chamber so that the pressure therein drops over a period of time.

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  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Control Of Fluid Pressure (AREA)
  • Safety Valves (AREA)
  • Fluid-Driven Valves (AREA)
  • Magnetically Actuated Valves (AREA)
US467100A 1973-05-08 1974-05-06 Fluid flow control valve Expired - Lifetime US3926211A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
ZA00733118A ZA733118B (en) 1973-05-08 1973-05-08 Fluid flow control valve

Publications (1)

Publication Number Publication Date
US3926211A true US3926211A (en) 1975-12-16

Family

ID=25566299

Family Applications (1)

Application Number Title Priority Date Filing Date
US467100A Expired - Lifetime US3926211A (en) 1973-05-08 1974-05-06 Fluid flow control valve

Country Status (12)

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US (1) US3926211A (pt)
JP (1) JPS5031431A (pt)
BR (1) BR7403698D0 (pt)
CA (1) CA999210A (pt)
CH (1) CH586363A5 (pt)
DE (1) DE2421600A1 (pt)
ES (1) ES426059A1 (pt)
FR (1) FR2229002B1 (pt)
GB (1) GB1463873A (pt)
IL (1) IL44764A (pt)
IT (1) IT1012185B (pt)
ZA (1) ZA733118B (pt)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4396032A (en) * 1981-04-09 1983-08-02 Pittman Products, Inc. Safety underwater pressure regulator
US5396918A (en) * 1993-11-18 1995-03-14 Agricultural Products, Inc. Water pressure regulator and method for regulating pressure through a valve
US5534896A (en) * 1993-07-19 1996-07-09 Hewlett-Packard Company Tubeless ink-jet printer priming cap system and method
US5714991A (en) * 1995-03-03 1998-02-03 Hewlett-Packard Company Rotary priming system for inkjet printheads
US5921275A (en) * 1997-03-27 1999-07-13 Emerson Electric Co. Apparatus for reducing noise generated by the flow of water through a water valve

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US815912A (en) * 1905-07-19 1906-03-20 Arthur H Eddy Expansion-valve.
US973609A (en) * 1910-04-25 1910-10-25 John A Abrams Pressure-regulating valve for gas-burners.
US1978398A (en) * 1928-10-27 1934-10-30 Becker Alfred Curt Gas-pressure regulator
US2861587A (en) * 1955-11-25 1958-11-25 Westinghouse Air Brake Co Vent valve device
US3270757A (en) * 1963-10-01 1966-09-06 Engler Alfred Dual diaphragm pressure regulator

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US815912A (en) * 1905-07-19 1906-03-20 Arthur H Eddy Expansion-valve.
US973609A (en) * 1910-04-25 1910-10-25 John A Abrams Pressure-regulating valve for gas-burners.
US1978398A (en) * 1928-10-27 1934-10-30 Becker Alfred Curt Gas-pressure regulator
US2861587A (en) * 1955-11-25 1958-11-25 Westinghouse Air Brake Co Vent valve device
US3270757A (en) * 1963-10-01 1966-09-06 Engler Alfred Dual diaphragm pressure regulator

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4396032A (en) * 1981-04-09 1983-08-02 Pittman Products, Inc. Safety underwater pressure regulator
US5534896A (en) * 1993-07-19 1996-07-09 Hewlett-Packard Company Tubeless ink-jet printer priming cap system and method
US5396918A (en) * 1993-11-18 1995-03-14 Agricultural Products, Inc. Water pressure regulator and method for regulating pressure through a valve
US5714991A (en) * 1995-03-03 1998-02-03 Hewlett-Packard Company Rotary priming system for inkjet printheads
US5921275A (en) * 1997-03-27 1999-07-13 Emerson Electric Co. Apparatus for reducing noise generated by the flow of water through a water valve

Also Published As

Publication number Publication date
ES426059A1 (es) 1976-11-16
CH586363A5 (pt) 1977-03-31
BR7403698D0 (pt) 1975-01-07
AU6868974A (en) 1975-11-13
IL44764A0 (en) 1974-07-31
IT1012185B (it) 1977-03-10
CA999210A (en) 1976-11-02
JPS5031431A (pt) 1975-03-27
IL44764A (en) 1976-12-31
DE2421600A1 (de) 1974-11-28
FR2229002B1 (pt) 1980-04-04
GB1463873A (en) 1977-02-09
FR2229002A1 (pt) 1974-12-06
ZA733118B (en) 1975-01-29

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Legal Events

Date Code Title Description
AS Assignment

Owner name: DUTTON PLASTICS ENGINEERING (PTY) LTD. 288 DIENST

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:AECI LIMITED A CORP. OF SOUTH AFRICA;REEL/FRAME:003990/0484

Effective date: 19820426

AS Assignment

Owner name: COOKSON (SA) (PROPRIETARY) LIMITED, 5TH FLOOR, SAN

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:DUTTON PLASTICS ENGINEERING (PROPRIETARY) LIMITED;REEL/FRAME:004979/0088

Effective date: 19880923

AS Assignment

Owner name: ZIMCO INDUSTRIES (PTY) LTD

Free format text: CHANGE OF NAME;ASSIGNOR:COOKSON (SA) (PROPRIETARY) LIMITED;REEL/FRAME:005238/0889

Effective date: 19891221