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WO1997037162A1 - Regulateur de pression ameliore par un accelerateur a action directe - Google Patents

Regulateur de pression ameliore par un accelerateur a action directe Download PDF

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Publication number
WO1997037162A1
WO1997037162A1 PCT/US1997/005119 US9705119W WO9737162A1 WO 1997037162 A1 WO1997037162 A1 WO 1997037162A1 US 9705119 W US9705119 W US 9705119W WO 9737162 A1 WO9737162 A1 WO 9737162A1
Authority
WO
WIPO (PCT)
Prior art keywords
boost
pressure regulator
gas pressure
set forth
seat
Prior art date
Application number
PCT/US1997/005119
Other languages
English (en)
Inventor
Christopher G. Turney
Paul W. Heald
Original Assignee
S.H. Leggitt Company
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 S.H. Leggitt Company filed Critical S.H. Leggitt Company
Priority to CA002248562A priority Critical patent/CA2248562C/fr
Priority to EP97917695A priority patent/EP0888510A4/fr
Priority to US08/952,547 priority patent/US5881765A/en
Priority to NZ331761A priority patent/NZ331761A/xx
Priority to AU25954/97A priority patent/AU726201C/en
Publication of WO1997037162A1 publication Critical patent/WO1997037162A1/fr

Links

Classifications

    • G—PHYSICS
    • G05—CONTROLLING; REGULATING
    • G05D—SYSTEMS FOR CONTROLLING OR REGULATING NON-ELECTRIC VARIABLES
    • G05D16/00—Control of fluid pressure
    • G05D16/04—Control of fluid pressure without auxiliary power
    • G05D16/06—Control of fluid pressure without auxiliary power the sensing element being a flexible membrane, yielding to pressure, e.g. diaphragm, bellows, capsule
    • G05D16/063—Control of fluid pressure without auxiliary power the sensing element being a flexible membrane, yielding to pressure, e.g. diaphragm, bellows, capsule the sensing element being a membrane
    • G05D16/0644—Control of fluid pressure without auxiliary power the sensing element being a flexible membrane, yielding to pressure, e.g. diaphragm, bellows, capsule the sensing element being a membrane the membrane acting directly on the obturator
    • G05D16/0655—Control of fluid pressure without auxiliary power the sensing element being a flexible membrane, yielding to pressure, e.g. diaphragm, bellows, capsule the sensing element being a membrane the membrane acting directly on the obturator using one spring-loaded membrane
    • G05D16/0658—Control of fluid pressure without auxiliary power the sensing element being a flexible membrane, yielding to pressure, e.g. diaphragm, bellows, capsule the sensing element being a membrane the membrane acting directly on the obturator using one spring-loaded membrane characterised by the form of the obturator

Definitions

  • This invention is applicable to a wide range of gas pressure-regulating applications, but is designed for particularly advantageous use in propane outdoor cooking appliance applications.
  • the device may be used to supply an appliance with a consistent pressure in the range of 11 inches of water column when provided with inlet pressures up to 250 psig.
  • Many conventional devices used in these applications experience three flow performance limitations that are inherent to their design.
  • the first limitation is termed "droop,” i.e. pressure droop, which is caused by the change in the effective area of the diaphragm as it moves and the loss of load experienced by the diaphragm control spring throughout the same motion.
  • the described invention partially overcomes this limitation by using velocity boosting to compensate.
  • Velocity boosting subjects the diaphragm to a lower pressure than the controlled downstream pressure, which allows for a larger valve opening and higher flow rates.
  • the second limitation, hysteresis or backlash is partially caused by change of direction of friction forces throughout the range of motion for the device. Hysteresis causes inconsistency in the performance of such a device.
  • the described invention reduces the effect of this limitation by providing a novel floating suspension for valving and velocity-boost components together with smoothly rounded continuous guides and slide surfaces providing essentially point-to-point controlled, low-friction contact for mechanism control.
  • the principal object of the invention is to provide a new and novel gas pressure regulator for use in propane outdoor cooking appliance applications and the like, different from the type customarily used heretofore in this field, having novel and advantageous structures and features which provide significantly improved results.
  • a further object of the invention is to provide an enhanced-performance, single-stage regulator valve having novel and advantageous physical componentry which cooperatively provides substantially and uniquely improved results and enables use of very small inlet orifice diameter, small diaphragm diameter and small overall regulator size, providing for reduced costs as well as implementation advantages.
  • a still further and more particular object of the invention is to provide an improved pressure regulator valve having novel internal componentry which provides velocity boosting features in a novel and enhanced manner.
  • Another important object of the invention is to provide an enhanced- performance, low-cost regulator that lends itself effectively to the use of automated manufacturing equipment and provides for ease of assembly. Additional objects of the invention, as well as additional advantages thereof, will become apparent following consideration of the ensuing disclosure.
  • Fig. 1 is a perspective representation of an assembled pressure regulator in accordance with the invention that shows external features of a single-outlet version of the device;
  • Fig. 2 is a perspective representation of an assembled regulator in accordance with the invention that shows external features of a dual-outlet version of the device;
  • Fig. 3 is a trimetric cross-sectional view of a regulator in accordance with the invention which shows the shape, location and relationship of internal components of the device;
  • Fig. 4 is an enlarged cross-sectional side view of a regulator in accordance with the invention further illustrating internal components and their respective features;
  • Fig. 5 is a trimetric view of the diaphragm assembly used in the regulator shown in the preceding figures;
  • Fig. 6 is a trimetric view of the internal mechanism of the regulator, showing the boost/seat tube with its mounting and actuation means;
  • Fig. 7 is a right side view of the internal mechanism of the regulator shown in Fig. 6;
  • Fig. 8 is a two-view perspective showing the valve- controlling actuator used in the preferred embodiment, which comprises part of the diaphragm assembly shown in Fig. 5;
  • Fig. 9A is a perspective view of the preferred boost/seat tube structure used in the regulator.
  • Fig. 9B is an end elevational view of the preferred boost/seat tube structure
  • Fig. 10A is a perspective view of the preferred orifice insert used in the regulator
  • Fig. 10B is an end elevational view of the preferred orifice insert structure
  • Fig. 11 is an enlarged front cross-sectional view showing the gas inlet of the valve body with its inlet fitting and seal
  • Fig. 12 is an enlarged side view of the preferred boost/seat tube, showing the force vectors acting thereon during operation.
  • a regulator valve 53 is comprised of a generally circular dish- shaped bonnet 11 and a corresponding body 12 that are secured together by mechanically deforming a ring of material 54 on body 12 to fold over a flange 55 on bonnet 11.
  • a generally circular fabric-reinforced elastomeric diaphragm 13 that features a molded convolution 31 is sealingly captured between bonnet 11 and body 12 to form an upper chamber 57 and a lower chamber 56.
  • This seal is formed by the squeeze of an integral seal bead 30 extending around the edge of diaphragm 13 between flange 55 and a seal groove 28 formed in the top of body 12.
  • Diaphragm 13 is combined with a diaphragm plate 14, relief spring 17, spring retainer 15, and actuator 16 to complete diaphragm assembly 59 (See Fig. 5).
  • Actuator 16 has an upstanding central post 42 (Figs. 7 and 8) having a plurality of longitudinal ribs 41 that aid in centering diaphragm 13 and diaphragm plate 14 during assembly of these parts.
  • Spring retainer 15 is a disc-like member having a central hole 36 (Fig. 4) that slips over post 42 of actuator 16 and includes an annular skirt or ledge 37 (Fig. 5) that compresses relief spring 17 against diaphragm plate 14.
  • Diaphragm assembly 59 is preferably secured by an ultrasonic heat-stake operation that fixes the position of spring retainer 15 on post 42 of actuator 16.
  • Actuator 16 has a lower extremity 16A which contacts and interacts with boost/seat tube 20, as described below, to form the control mechanism of the regulating valve.
  • a control spring 18 (Fig.4) is compressed and centered between the top inside surface 60 of bonnet 11 and ring 34 of diaphragm plate 14.
  • Boost/seat tube 20 houses a seat disk 21 (Figs 4 and 9B) by means of a seat holder 50 that is suspended centrally by support ribs 51 within a smooth and otherwise- unrestricted tubular passage 52 (Fig. 9A) extending longitudinally through the boost/ seat tube.
  • Boost/ seat tube 20 is restricted to linear motion toward or away from a valve seat
  • Orifice insert 19 which is aligned with seat disk 21 and defined by an orifice insert member 19 (Figs. 4 and 10).
  • Orifice insert 19 is held in body 12 by a pair of drive screws 23 and has an o- ring 22 which encircles its lower cylindrical extremity 45 and forms a seal between orifice insert 19 and body 12.
  • Inlet 26 of body 12 is designed to accept an inlet fitting 65 (See Fig. 11) that connects regulator valve 53 to a source of gas such as a propane supply cylinder valve.
  • a seal is formed between inlet fitting 65 and body 12 by o-ring 67 to prevent gas leakage to atmosphere.
  • Inlet fitting 65 is retained in body 12 by mechanically deforming inlet boss 68 on body 12 so as to force material from boss 68 into groove 66.
  • pressurized gas from a source is applied to inlet 26, through which the gas may flow into passage 61 , through orifice 43 (when the valve mechamsm is open), around seat disk 21 and seat holder 50, through the tubular boost passage 52 and out passage 58 to the appliance.
  • the initial compression of control spring 18 between bonnet 11 and diaphragm assembly 59 upon assembly forces the valve mechanism to be in the full open position before inlet gas pressure is applied to inlet 26.
  • orifice 43 is elongated and preferably oriented at an angle with respect to inlet passage
  • the diameter of orifice 43 may be considerably smaller than would otherwise be required to meet outlet flow requirements (on the order of only half that size), due to the velocity boost effect provided, helping to maintain acceptably low lockup (shutoff) inlet pressure differentials. Accordingly, the inlet gas flow substantially restricted and accelerated by the small inlet orifice, flares out around seat disk 21 and accelerates past this smoothly rounded restriction due to the "vena contracta" effect, flowing with increased velocity axially of and along boost passage 52 into outlet passage 58.
  • the operating mechanism of the described invention is mainly composed of actuator 16, boost/ seat tube 20, and orifice insert 19.
  • Actuator 16 features a pair of mutually spaced control channels 38 in its lower extremity 16A, and also has a flat vertical surface 40.
  • the control channels 38 each provide a pair of oppositely disposed identically contoured surfaces 63, 64 which make sliding contact with one or the other of the opposite sides of a pair of control pins 48 extending outwardly from each side of boost/seat tube 20, to form a camming mechanism.
  • control channels 38 are preferably designed to provide a mechanical advantage of about 4: 1 to ensure a seal between seat disk 21 and valve seat 44 when there is no downstream demand, and to provide a lower mechanical advantage throughout the rest of the valve mechanism motion, to induce and enhance velocity boosting effects.
  • the minimal, reduced-area points of contact between the contoured surfaces 63, 64 and control pins 48 aid in the reduction of hysteresis, but the overall manner in which the boost/seat tube 20 is supported, moved and guided provides a very significant reduction in friction for the overall mechanism, with corresponding improved regulator operation, as noted further below.
  • Boost/seat tube 20 is restricted to move in a linear fashion toward or away from valve seat 44 by the outermost end portions of control pins 48 and by a pair of guide pins 49 extending from opposite sides of the boost/seat tube 20 at a location along its length spaced from pins 48 (Figs. 6, 7, and 9), which ride along guide surfaces 47, 70 that are formed on the underside of generally cylindrical guides 72, 73 formed on the extended ends of upstanding arms 69, 71 of orifice insert 19 (Figs. 6, 7, and 10).
  • the contact points between these pins and guides are the transverse intersection of cylindrical shapes, providing smoothly rounded point-to-point contact area that reduce friction in the motion of the boost/seat tube 20 and related valve mechanism.
  • Orifice insert 19 also has two contact points 46 (Figs. 4 and 10B) that contact the flat vertical surface 40 of actuator 16 to provide consistent bi-directional linear motion with reduced friction.
  • the structure and interrelationship of the slidable mechanism just described produces a unique low-friction support and guidance arrangement for the boost/ seat tube 20. More particularly, as indicated above and as shown in Fig. 7 (depicting the mechanism in actual operation), the boost/seat tube 20 becomes elevated during operation, with control pins 48 and guide pins 49 riding along the underside of guide surfaces 70 and 47 respectively rather than along the top of cylindrical member 72.
  • Control Force vector on pin 48 represents its engagement with the contoured control channel 38, in particular surface 63 thereof.
  • the "Unbalance Force” essentially represents the inlet gas pressure acting on the face of the valve disk 21 and its annular mount 50.
  • the boost/seat mbe 20 is loosely slid into its position between arms 69 and 71 of the orifice insert 19, with pins 48 disposed between guide projections 72 and 73 and pins 48 and 49A resting atop guide projection 72.
  • the axially displaced disposition of pins 49A with respect to pins 49 tends to limit the extent of allowable boost/seat tube tilt under these conditions since they engage the elongated guide surface 72 at different points and can be used to hold the forward portion of the boost/seat tube 20 in a somewhat elevated position in which seat disk 21 remains somewhat aligned with seat/orifice 43.
  • Actuator 16 is then inserted into place from above, along with the rest of diaphragm assembly 59, with cam slots 38 sliding over and receiving pins 48.
  • the bonnet 11 is then positioned over the diaphragm assembly and secured in place.
  • the top surface 60 of bonnet 11 contacts the top of control spring 18 and applies the aforementioned preload to it, while at the same time forcing actuator 16 downwardly.
  • valve seat disk 21 the force of the inlet gas pressure acting on valve seat disk 21 creates the "Unbalance Force" noted above in connection with Fig. 12. As shown there, this force vector is generally aligned along the axis of boost/seat tube 20, and below the control pins 48. The effect of this is to elevate the entire boost/ seat tube 20 by rotating it to the position shown in Fig. 7, wherein pins 48 and 49A are moved upward to a position above and spaced from guide projections 72. In this position, the top of pins 48 engage the underside surface 70 of guide member 73, and the top of pins 49 engage the underside 47 of guide members 72, thereby creating the low-friction smoothly guided operating conditions noted above.
  • the described invention also includes a safety feature commonly referred to as pressure relief. If pressure increases in chamber
  • post 42 of actuator 16 is designed to contact surface 60 of bonnet 11, stopping the vertical motion and allowing the relief mechamsm to operate as described above.
  • the mechanism of this device operates to control flow to meet downstream demand.
  • outlet pressure decreases and this results in downward movement of diaphragm 13 and its related parts, including actuator 16, causing seat disk 21 to move away from valve seat 44 and thereby allowing more flow through the device to supply the new demand. This continues until the demand is satisfied and an equilibrium state is reached. Conversely, the same events occur in reverse for conditions of decreasing demand. Changes in inlet pressure and/or demand will cause the device to compensate by opening or closing the valve mechamsm in response to the new conditions, to again reach an equilibrium state.
  • boost/ seat mbe 20 and seat disk 21 in the opposite direction, at times when the flow of gas is being reduced, moves the end of boost/seat tube 20 away from the entrance to outlet passage 58, causing an increased widening of the opening into chamber 56 and reducing the velocity-boost/pressure-aspiration effects and allowing increased pressure within the latter. Accordingly, the velocity boosting effect provided by the boost/seat mbe 20 is correspondingly varied, and enhanced. Tlirough the use of enhanced velocity boosting and reduced hysteresis, the described invention provides a pressure regulator having considerably improved operation.
  • Bonnet 11 (aluminum), body 12 (zinc), diaphragm plate 14 (plated steel), spring retainer 15 (plated steel), control spring 18 (stainless steel), relief spring 17 (stainless steel), and drive screw 23 (stainless steel) are preferably all rigid metal components.
  • Diaphragm 13, seat disk 21, and o-ring 22 are flexible elastomeric components.
  • Acmator 16, boost/seat tube 20, and orifice insert 19 are preferably constructed of rigid engineering thermoplastic resins such as Acetal, Polyethylene Terephthalate.
  • body 112 offers a second integral barbed outlet 124 with through-hole 158 to provide gas flow to appliances that have both a main burner and a smaller capacity side burner for propane outdoor cooking appliance applications.
  • the described invention provides consistent repeatable performance over a wide range of inlet pressures and flow rates while also enabling significant reduction in inlet orifice diameter (as much as one-half) and in diaphragm and overall regulator size; e.g. , on the order of as much as one-third, compared to conventional diaphragm-type regulators.
  • inlet orifice diameter as much as one-half
  • diaphragm and overall regulator size e.g. , on the order of as much as one-third, compared to conventional diaphragm-type regulators.
  • the foregoing detailed description is considered that of a preferred embodiment only, and the particular shape and nature of at least some of the components (especially the orifice insert 19 and boost/seat tube 20) in this embodiment are at least partially based on manufacturing (e.g. , molding) advantages and considerations as well as on those pertaining to assembly and operation.

Landscapes

  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • General Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Automation & Control Theory (AREA)
  • Control Of Fluid Pressure (AREA)
  • Fluid-Driven Valves (AREA)
  • Lift Valve (AREA)
  • Seasonings (AREA)
  • Confectionery (AREA)

Abstract

Un régulateur (53) de pression de gaz amélioré par un accélérateur comprend un capot (11) ainsi qu'un corps (12; logement principal) fixés ensemble de manière à maintenir une membrane (13) entre les deux constituants. Un actuateur (16) présentant une paire de canaux de commande (38) et un siège de surpression (32) dans un constituant est relié à la membrane (13) de manière à être déplacé avec et par cette dernière. Un tube accélérateur/à siège (20) présente des surfaces extérieures de guidage (49) servant à guider et à commander son mouvement, il présente également un passage intérieur (52) d'écoulement de gaz dans lequel est monté un disque à siège élastomère (21; élément soupape). Le tube accélérateur/à siège (20) est limité à un déplacement linéaire (action directe) par rapport à un orifice d'admission/siège de soupape (44) par une pluralité de surfaces de guidage (49) constituant une partie intégrante de l'insert d'orifice (44) sur lequel certaines zones de contact (70, 72) du tube accélérateur/à siège (20) peuvent coulisser.
PCT/US1997/005119 1996-03-29 1997-03-28 Regulateur de pression ameliore par un accelerateur a action directe WO1997037162A1 (fr)

Priority Applications (5)

Application Number Priority Date Filing Date Title
CA002248562A CA2248562C (fr) 1996-03-29 1997-03-28 Regulateur de pression ameliore par un accelerateur a action directe
EP97917695A EP0888510A4 (fr) 1996-03-29 1997-03-28 Regulateur de pression ameliore par un accelerateur a action directe
US08/952,547 US5881765A (en) 1997-03-28 1997-03-28 Direct-acting boost-enhanced pressure regulator
NZ331761A NZ331761A (en) 1996-03-29 1997-03-28 Direct-acting boost-enhanced pressure regulator
AU25954/97A AU726201C (en) 1996-03-29 1997-03-28 Direct-acting boost-enhanced pressure regulator background and general summary of the invention

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US1429096P 1996-03-29 1996-03-29
US60/014,290 1996-03-29

Publications (1)

Publication Number Publication Date
WO1997037162A1 true WO1997037162A1 (fr) 1997-10-09

Family

ID=21764590

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US1997/005119 WO1997037162A1 (fr) 1996-03-29 1997-03-28 Regulateur de pression ameliore par un accelerateur a action directe

Country Status (6)

Country Link
EP (1) EP0888510A4 (fr)
CN (1) CN1143069C (fr)
AU (1) AU726201C (fr)
CA (1) CA2248562C (fr)
NZ (1) NZ331761A (fr)
WO (1) WO1997037162A1 (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US9709998B2 (en) 2013-03-14 2017-07-18 Marshall Excelsior Co. Pressure regulator

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2012126182A1 (fr) * 2011-03-24 2012-09-27 Fisher Regulators (Shanghai) Co., Ltd. Régulateur de pression à écoulement axial équilibré

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2015930A (en) * 1933-09-28 1935-10-01 Mueller Co Fluid pressure regulator
US2095210A (en) * 1927-12-30 1937-10-05 Union Carbide & Carbon Corp Fluid regulator
US4972871A (en) * 1988-02-29 1990-11-27 Fisher Controls International, Inc. Boost modified, droop compensated direct acting pressure regulator
US5103861A (en) * 1991-08-21 1992-04-14 Chen Fong Enterprise Co., Ltd. Sealing means for a two-stage gas regulator for liquefied-gas containers

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2519798A (en) * 1945-03-08 1950-08-22 Cash A W Co Pressure regulating valve
US2951494A (en) * 1955-07-25 1960-09-06 Bendix Corp Pressure regulating valve
US4842013A (en) * 1988-02-29 1989-06-27 Fisher Controls International, Inc. Droop compensated direct acting pressure regulator

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2095210A (en) * 1927-12-30 1937-10-05 Union Carbide & Carbon Corp Fluid regulator
US2015930A (en) * 1933-09-28 1935-10-01 Mueller Co Fluid pressure regulator
US4972871A (en) * 1988-02-29 1990-11-27 Fisher Controls International, Inc. Boost modified, droop compensated direct acting pressure regulator
US5103861A (en) * 1991-08-21 1992-04-14 Chen Fong Enterprise Co., Ltd. Sealing means for a two-stage gas regulator for liquefied-gas containers

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See also references of EP0888510A4 *

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US9709998B2 (en) 2013-03-14 2017-07-18 Marshall Excelsior Co. Pressure regulator

Also Published As

Publication number Publication date
AU726201C (en) 2001-12-06
EP0888510A4 (fr) 1999-06-23
AU2595497A (en) 1997-10-22
EP0888510A1 (fr) 1999-01-07
NZ331761A (en) 2000-04-28
CA2248562C (fr) 2002-02-26
CN1215467A (zh) 1999-04-28
CN1143069C (zh) 2004-03-24
CA2248562A1 (fr) 1997-10-09
AU726201B2 (en) 2000-11-02

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