US2967536A - Respiratory gas flow regulators - Google Patents

Respiratory gas flow regulators Download PDF

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Publication number
US2967536A
US2967536A US668391A US66839157A US2967536A US 2967536 A US2967536 A US 2967536A US 668391 A US668391 A US 668391A US 66839157 A US66839157 A US 66839157A US 2967536 A US2967536 A US 2967536A
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US
United States
Prior art keywords
pressure
chamber
valve
passage
supply
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
US668391A
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English (en)
Inventor
Urban F Stratman
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.)
Bendix Corp
Original Assignee
Bendix Corp
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 Bendix Corp filed Critical Bendix Corp
Priority to US668391A priority Critical patent/US2967536A/en
Priority to DEB49225A priority patent/DE1124821B/de
Application granted granted Critical
Publication of US2967536A publication Critical patent/US2967536A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60C—VEHICLE TYRES; TYRE INFLATION; TYRE CHANGING; CONNECTING VALVES TO INFLATABLE ELASTIC BODIES IN GENERAL; DEVICES OR ARRANGEMENTS RELATED TO TYRES
    • B60C13/00—Tyre sidewalls; Protecting, decorating, marking, or the like, thereof
    • B60C13/04—Tyre sidewalls; Protecting, decorating, marking, or the like, thereof having annular inlays or covers, e.g. white sidewalls
    • A—HUMAN NECESSITIES
    • A62—LIFE-SAVING; FIRE-FIGHTING
    • A62B—DEVICES, APPARATUS OR METHODS FOR LIFE-SAVING
    • A62B9/00—Component parts for respiratory or breathing apparatus
    • A62B9/02—Valves
    • A62B9/022—Breathing demand regulators
    • 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
    • G05D16/0675—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 on the obturator through a lever
    • G05D16/0683—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 on the obturator through a lever using a spring-loaded membrane
    • G05D16/0686—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 on the obturator through a lever using a spring-loaded membrane characterised by the form of the lever
    • 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
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S116/00—Signals and indicators
    • Y10S116/42—Oil filter
    • 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
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S137/00—Fluid handling
    • Y10S137/908—Respirator control
    • 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
    • Y10T137/7754—Line flow effect assisted
    • Y10T137/7756—Reactor surface separated from flow by apertured partition
    • Y10T137/7757—Through separate aperture
    • 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]
    • Y10T137/7831—With mechanical movement between actuator and valve

Definitions

  • Such regulators are connected in respiratory gas supply circuits between the gas source and the users respirator. They include supply valve means for opening and closing the supply circuit, means to determine when the user is inhaling and exhaling, and means to cause or permit the valve means to open and close in accordance with inhalation and exhalation respectively. These conditions are determined by sensing pressure changes at the downstream or outlet side of the regulator; and the sensing means most commonly employed is a diaphragm which forms a wall of a pressure chamber. This chamber is connected by a passageway to the gas supply passage at or near the outlet so that the chamber pressure will vary in accordance with pressure at the outlet.
  • the problem will be solved if the change in pressure in the outlet can be amplified sufliciently in the pressure chamber; and another object of the invention is to provide such amplification.
  • the pressure chamber and the supply outlet are connected together so that special means are required to provide a different pressure change in the pressure chamber than in the outlet; and the provision of such means is another object of the invention.
  • the gas flow is divided into two streams, one of which is directed into the pressure chamber, and the other of which is directed toward the supply outlet and is arranged to aspirate gas from the pressure chamber.
  • the two streams flow simultaneously when the supply valve is open but rather than simply opposing one another, it has been demonstrated that the aspirating stream acts, when the supply valve opens, to cause the valve opening to increase rapidly to the required degree, and that the other stream acts, when inhalation flow ceases, to build up pressure in the chamber rapidly whereby the supply valve is closed rapidl y.
  • Fig. 1 is a view in section-of a respiratory gas flow regulator embodying the invention.
  • Fig. 2 is a top plan view of the nozzle employed in Fig. 1.
  • the regulator advantageously comprises a body, a respiratory gas supply passage in the body, supply valve means in the supply passage for opening and closing said passage, a pressure sensing chamber in the body having a pressure sensitive diaphragm in one wall of the chamber, a passage connection from the pressure chamber to the supply passage downstream from the valve means, and a leverage system by which movement of the diaphragm is made to actuate the supply valve. It further comprises means for utilizing the kinetic energy of respiratory gas flow for amplifying, in the pressure chamber, the pressure variations at the downstream side of the supply passage.
  • Fig. 1 wherein the body 10 is divided into upper and lower body sections 11 and 12 and a cover section 13.
  • the supply passage 14 is formed in the lower body section 12 where it begins at an inlet passage 15 and extends through a valve chamber 16 and a connecting passage 1'7 to a supply outlet passage 18 where it terminates at an outlet 18A which opens to the passage 19 of a hose connector 20 secured in any convenient manner, such as by bolts 21, to the lower body section 12.
  • the supply passage is opened and closed by a suitable valve of any well known type.
  • a balanced valve is advantageously used because such valves are easily operated.
  • the balanced valve 24 shown in valve chamber 16 is of a type well known in the art and the details of its construction are not important here except that the valve head 25 is moved toward and away from its seat 26 by axial movement of an actuating rod 23 fixed to head 25. This rod extends from valve head 25 through a low-friction sealing bushing 27, pressed into an opening 28 connecting the valve chamber with the upper face 290i body section 12, and into the central opening 30 of the upper body section 11.
  • Section 11 comprises a cylindrical wall 33 and an outwardly extending rectangular flange 34, and it is secured by any convenient means, to the upper face 29 of the lower body section.
  • the cover 13 is cup-shaped; it is inverted and placed over the wall 33 of body section 11 so that its rim rests on flange 34 and so that its end wall 37 is spaced from the upper face 38 of section 11.
  • the cylindrical side wall 39 of the cover surrounds the wall 33 and is separated therefrom by an annular sealing gasket
  • the central opening 30 in upper body section 11 is covered by a circular pressure sensitive diaphragm assembly including a flexible diaphragm 45, supporting disks 46 and 47 overlying the central portion of the upper and lower faces of the diaphragm, and a clamping ring 48 which is held down by machine screws 49 to clamp the outer margin of the diaphragm 45 against the upper face 38 of the body section 11.
  • the lower face of the diaphragm 4-5 is subjected to atmospheric pressure which is communicated to space 30 through a groove 32 formed in the lower face of the upper section 11 and connecting space 30 with the atmosphere.
  • the means for operating the balanced valve 24 in accordance with movement of diaphragm 45 may advantageously comprise, as shown, a pin 50 fixed to the center of the diaphragm assembly and extending into opening 30 where it is pivotally connected to one end of a lever 51.
  • the other end of the lever is connected to a fixed pivot 54- secured to the upper face 29 of the lower body.
  • the diaphragm 45 forms one wall of a pressure sensing chamber 60 which is further enclosed by the cover member 13 and the upper face 3-8 of body section 11.
  • Means are provided in the invention for producing amplified pressure changes in this chamber which vary in accordance with pressure changes in the supply outlet 18. These means include pressure transmitting passage means connecting the pressure chamber to the supply passage downstream from the supply valve, means for directing a stream of gas into the pressure chamber, and means for aspirating gas from the pressure chamber when the supply valve is open. One portion of the stream of gas flowing through the supply passage is diverted toward the pressure chamber and another portion is passed through an aspirator arranged to aspirate gas from the pressure chamber through the passage means.
  • two nozzles are employed in the supply passage to convert the stream of supply gas into jet streams; a first one is directed toward the pressure chamber and the other is directed toward the supply outlet from a point downstream from the pressure transmitting passage means.
  • the two nozzles are advantageously combined in a unitary double nozzle structure.
  • a single passage may be employed, as shown.
  • the supply passage is enlarged at its outlet end passage 18 and a pressure communicating passage 61, formed in body sections 11 and 12, connects.the pressure chamber 60 to the outlet passage.
  • a double nozzle 6?. is threaded into the supply passage upstream from the outlet passage 18 so that its front or downstream end projects into the outlet passage past the point at which the pressure transmitting passage 61 opens into the outlet passage 18.
  • Its aspirating opening 63 opens at the front of the nozzle where it converts the stream of gas flowing in the supply passage into a high velocity or jet stream directed toward the outlet.
  • the jet stream creates a pressure drop which aspirates gas from the pressure chamber 60.
  • the other nozzle opening 64 is located at the side of the nozzle 62 opposite the opening of the pressure transmitting passage 61. It diverts gas flow from the supply passage and directs it in a high velocity or jet stream into the pressure transmitting passage 61 toward pressure chamber 69.
  • Gas rushing past the valve toward the nozzle 62 is divided at the nozzle into two streams, one directed toward the pressure transmitting passage and the other or aspirating stream directed toward the outlet.
  • the aspirating stream has the greater effect; it flows freely out of the regulator toward the inhaling user aspirating gas from chamber 60 and passage 61 including the gas flowing into passage 61 through the side opening 64 of the nozzle.
  • the effect is to withdraw more gas from chamber 60 than the user could by his inhalation alone so that the diaphragm 45 is moved up and supply valve 24 is opened rapidly.
  • the pressures in the regulator will remain in dynamic balance.
  • the flow from both nozzle openings will increase or decrease in the same proportion as the valve opening is varied, and whether the flow from the side opening 64 is immediately aspirated toward the outlet or will act to increase pressure in chamber 60, will depend upon the inhalation suction or resistance to flow experienced by the aspirating stream at the regulator outlet.
  • the regulator may be adjusted to provide a given degree of diaphragm displacement and supply valve opening for a given pressure at the regulator outlet by adjustment of the relative quantity of gas flow through the two nozzle openings; and the provision of this feature is another object of the invention.
  • the means for adjusting the relative flows through these openings advantageously comprises, as shown, a split ring 65 made of spring material which embraces the nozzle body and can be slid back and forth along the body to cover a lesser or greater portion of the side opening 64. The adjustment need be made only once and is made using a tool such as a screw driver inserted down through the pressure transmitting passage when the regulator is factory-adjusted with cover 13 removed during calibration at a test stand.
  • a respiratory gas flow regulator comprising a body, a gas supply passageway in the body originating at an inlet and terminating in a supply outlet, and means for regulating the flow of gas through said passageway, comprising a valve in the passageway, and means for operating the valve in accordance with pressure variations at the outlet, including a passage chamber connected to the outlet, a presssure responsive diaphragm in a wall of the chamber, valve actuating means connecting said valve and diaphragm and operated by the diaphragm for opening the valve when the chamber pressure is reduced and closing the valve when the chamber pressure is increased, means for increasing the drop in pressure in the chamber when outlet pressure is reduced, and means for increasing the rise in pressure in the chamber when the outlet pressure rises.
  • a respiratory gas flow regulator comprising a body, a gas supply passageway formed in said body originating at an inlet and terminating in a supply outlet, and means for regulating the flow of gas through said passageway comprising a valve in the passageway and means for operating the valve in accordance with pressure variations at the outlet, including a pressure chamber, passage means connecting said chamber to said passageway downstream from said valve, a pressure responsive diaphragm in a wall of the chamber, valve actuating means operated by the diaphragm for opening the valve when the chamber pressure is reduced and closing the valve when the chamber pressure is increased, and means for amplifying pressure changes in said chamber in accordance with pressure changes at said outlet, including aspirating means responsive to gas flow in said supply passageway for aspirating gas from said chamber through said passage means, and means upstream from said aspirator means for diverting some of the gas flowing in said supply passageway toward said chamber through said passage means.
  • a respiratory gas flow regulator comprising a body, a gas supply passageway formed in said body originating at an inlet and terminating in a supply outlet, and means for regulating the flow of gas through said passageway comprising a valve in the passageway and means for operating the valve in accordance with pressure variations at the outlet, including a pressure chamber, passage means connecting said chamber to said passageway downstream from said valve, a pressure responsive diaphragm in a wall of the chamber, valve actuating means operated by the diaphragm for opening the valve when the chamber pressure is reduced and closing the valve when the chamber pressure is increased, and means for providing more rapid actuation of said valve, including means for diverting a jet stream of gas from the supply passageway into said passage means toward the chamber, and nozzle means in said supply passageway for aspirating gas from said chamber in response to gas flow in said supply passageway.
  • a respiratory gas flow regulator comprising a body, a gas supply passageway in said body originating at an inlet and terminating in a supply outlet, and means for regulating the flow of gas through said passageway comprising a valve in the passageway and means for operating the valve in accordance with pressure variations at the outlet, including a pressure chamber, a pressure responsive diaphragm in a wall of the chamber, valve actu ating means operated by the diaphragm for opening the valve when the chamber pressure is reduced and closing the valve when the chamber pressure is increased, nozzle means in said passageway downstream from said valve for converting flow of gas in said supply passageway into two jet streams one of them directed toward said supply outlet, and means for aspirating gas from said chamber in accordance with flow velocity in the other jet stream including passage means connecting said chamber to said supply passageway at the upstream side of said one jet, stream and opening to said supply passageway in the path of said other jet stream.
  • a respiratory gas flow regulator comprising a body, a gas supply passageway formed in said body originating at an inlet and terminating in a supply outlet, and means for regulating the flow of gas through said passageway comprising a valve in the passageway and means for operating the valve in accordance with pressure variations at the outlet, including a pressure chamber, passage means connecting said chamber to said passageway downstream from said valve, a pressure responsive diaphragm in a wall of the chamber, valve actuating means operated by the diaphragm for opening the valve when the chamber pressure is reduced and closing the valve when the chamber pressure is increased, and means including a first nozzle opening for diverting a jet stream of gas from said supply passageway into said passage means toward said chamber, and means including a second nozzle opening in said supply passageway for aspirating gas from said chamber in response to gas flow in said supply passageway.

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  • Health & Medical Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Pulmonology (AREA)
  • Mechanical Engineering (AREA)
  • Fluid Mechanics (AREA)
  • General Physics & Mathematics (AREA)
  • Automation & Control Theory (AREA)
  • General Health & Medical Sciences (AREA)
  • Business, Economics & Management (AREA)
  • Emergency Management (AREA)
  • Respiratory Apparatuses And Protective Means (AREA)
US668391A 1957-06-27 1957-06-27 Respiratory gas flow regulators Expired - Lifetime US2967536A (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
US668391A US2967536A (en) 1957-06-27 1957-06-27 Respiratory gas flow regulators
DEB49225A DE1124821B (de) 1957-06-27 1958-06-09 Lungengesteuertes Atemgaszufuehrungsventil fuer Atemschutzgeraete

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US668391A US2967536A (en) 1957-06-27 1957-06-27 Respiratory gas flow regulators

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US2967536A true US2967536A (en) 1961-01-10

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DE (1) DE1124821B (de)

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3086548A (en) * 1962-06-08 1963-04-23 Leslie Co Self-regulating pitot for regulator valves
US3221704A (en) * 1964-04-24 1965-12-07 Bendix Corp Fluid flow apparatus
US4147176A (en) * 1975-06-30 1979-04-03 Christianson Raymond Diaphragm assembly for the demand regulator of a breathing apparatus
USRE31932E (en) * 1975-06-30 1985-07-02 Diaphragm assembly for the demand regulator of a breathing apparatus
US4972868A (en) * 1990-02-08 1990-11-27 Fisher Controls International, Inc. Flow restrictor and diverter for direct acting pressure regulator
US4972871A (en) * 1988-02-29 1990-11-27 Fisher Controls International, Inc. Boost modified, droop compensated direct acting pressure regulator
US5285810A (en) * 1993-02-11 1994-02-15 Itt Corporation Pressure-reducing regulator for compressed natural gas
US5443083A (en) * 1993-02-11 1995-08-22 Itt Corporation Pressure-reducing regulator for compressed natural gas
US5931188A (en) * 1998-02-24 1999-08-03 Groth Corporation Diaphragm operated regulator valve for maintaining low gas pressure

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1933733A (en) * 1932-09-30 1933-11-07 Julius H Hess Infant incubator
US2536435A (en) * 1946-05-20 1951-01-02 E & J Mfg Company Resuscitator control means
US2616442A (en) * 1946-06-18 1952-11-04 Bendix Aviat Corp Respiratory device
US2774352A (en) * 1952-03-28 1956-12-18 John H Emerson Breathing assistor valve

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR955272A (de) * 1950-01-11
US1515911A (en) * 1922-06-30 1924-11-18 Cash A W Co Pressure reducing and regulating valve
US1885389A (en) * 1931-05-29 1932-11-01 Cash A W Co Pressure reducing and rgulating valve
FR56841E (fr) * 1947-06-30 1952-10-07 Bendix Aviat Corp Inhalateur d'oxygène

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1933733A (en) * 1932-09-30 1933-11-07 Julius H Hess Infant incubator
US2536435A (en) * 1946-05-20 1951-01-02 E & J Mfg Company Resuscitator control means
US2616442A (en) * 1946-06-18 1952-11-04 Bendix Aviat Corp Respiratory device
US2774352A (en) * 1952-03-28 1956-12-18 John H Emerson Breathing assistor valve

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3086548A (en) * 1962-06-08 1963-04-23 Leslie Co Self-regulating pitot for regulator valves
US3221704A (en) * 1964-04-24 1965-12-07 Bendix Corp Fluid flow apparatus
US4147176A (en) * 1975-06-30 1979-04-03 Christianson Raymond Diaphragm assembly for the demand regulator of a breathing apparatus
USRE31932E (en) * 1975-06-30 1985-07-02 Diaphragm assembly for the demand regulator of a breathing apparatus
US4972871A (en) * 1988-02-29 1990-11-27 Fisher Controls International, Inc. Boost modified, droop compensated direct acting pressure regulator
US4972868A (en) * 1990-02-08 1990-11-27 Fisher Controls International, Inc. Flow restrictor and diverter for direct acting pressure regulator
US5285810A (en) * 1993-02-11 1994-02-15 Itt Corporation Pressure-reducing regulator for compressed natural gas
US5443083A (en) * 1993-02-11 1995-08-22 Itt Corporation Pressure-reducing regulator for compressed natural gas
US5931188A (en) * 1998-02-24 1999-08-03 Groth Corporation Diaphragm operated regulator valve for maintaining low gas pressure

Also Published As

Publication number Publication date
DE1124821B (de) 1962-03-01

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