US3522818A - Pressure-reducing valve for breathing apparatus - Google Patents

Pressure-reducing valve for breathing apparatus Download PDF

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Publication number
US3522818A
US3522818A US687763A US3522818DA US3522818A US 3522818 A US3522818 A US 3522818A US 687763 A US687763 A US 687763A US 3522818D A US3522818D A US 3522818DA US 3522818 A US3522818 A US 3522818A
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United States
Prior art keywords
valve
pressure
piston
air
cylinder
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Expired - Lifetime
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US687763A
Inventor
Leszek Suchy
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ZAKLADY MECHANIKI PRECYZJNEJ
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ZAKLADY MECHANIKI PRECYZJNEJ
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Priority claimed from PL117924A external-priority patent/PL55641B1/pl
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    • 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
    • G05D16/10—Control of fluid pressure without auxiliary power the sensing element being a piston or plunger
    • 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
    • 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
    • G05D16/0402—Control of fluid pressure without auxiliary power with two or more controllers mounted in series
    • 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]
    • Y10T137/7795—Multi-stage
    • 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]
    • Y10T137/7809—Reactor surface separated by apertured partition
    • Y10T137/781—In valve stem
    • Y10T137/7811—Also through reactor surface

Definitions

  • the invention relates to a pressure-reducing valve of the first stage for a breathing apparatus provided with a two-stage pressure reducing system, which is able to maintain a constant average pressure independently of the pressure existing in the gas cylinder.
  • the compressed air coming from the cylinder is reduced to the breathing pressure by means of two pressure-reducing valves.
  • the first valve reduces the high pressure of the air coming from the air-supply cylinder to the intermediate pressure, which mostly does not exceed 8 atmospheres (atm).
  • the second valve controlled by the lung of the user reduces this pressure to a breathing pressure.
  • the pressure reducing valves of the first stage of known devices have the essential disadvantage that they do not ensure a constant intermediate pressure, which increases as the pressure in the cylinder drops.
  • the increase of the intermediate pressure depends only on the area ofthe throttling hole.
  • the higher pressure ofthe air coming from the cylinder upon the valve head of the pressurereducing valve effects a more intensive increase of the intermediate pressure.
  • These variations cause varied breathing resistances and disadvantageously .influence -the breathing characteristic of the device.
  • Use of the throttling hole of small area eliminates these disadvantages to some extent, but causes strong throttling of the flow at high demand of the air.
  • the pressure-reducing valve according to the invention has a simplified structure and permits use of a throttling hole of large cross-sectional area and able to cover any demand on air, and it simultaneously secures the constant intermediate pressure, independently of the pressure in the cylinder.
  • the task set in order to eliminate said inconveniences is, according to the invention, accomplished in such manner that the force acting unilaterally on the valve head and effecting the increase of the reduced intermediate pressure at decreasing pressure in the cylinder is eliminated;
  • the valve head is relieved by a force arising from the pressure of the air penetrating through a hole made in the valve head into the space closed by the piston, the latter being movable against the valve head and having an area equal to the area of thethrottling hole, so that the valve head is in stability.
  • FIG U RE of which is a longitudinal sectional 1 view of the valve.
  • the pressure-reducing valve consists of a valve body 1, a
  • cover 'l2fof the body a piston 16, and seals l5, l7 and 19 closing the spaces 13, 21 and a chamber 5.
  • cover 12 there 'are'made ports 8 leading the environmental (ambient) pres-
  • the described design may be used for breathing apparatus destined for moving under water, as well as for a paratus insulating the human breathing system from gases 0 the environment.
  • the mode of operation of the valve according to the invention is as follows:
  • the pressure of the spring 10 upon the piston 11 holds the valve head 6 open.
  • the air flows from the cylinder through the conduit 2 and the chamber 5 to the conduit 20, which leads the air to the breathing apparatus.
  • the air penetrates also through the hole l8 and the slot 14 to the space 13 above the piston ll.
  • the pressure of the air upon the piston Ill overcomes the resistance of the spring 10, causes a shifting of the piston, and closes the seat 4.
  • the air flows to the space 21 closed by the piston 16 abutting against the cover 12 of the valve body, creating thereby the fixed position of the piston 16 in relation to the valve seat 4.
  • a breathing apparatus comprising a compressed-air tank, a first valve connected to said tank for producing air at a constant intermediate pressure less than that in said cylinder, a second valve connected to said first valve for converting air at said intermediate pressure into air at breathing pressure, and a breathing device connected to said second valve for supplying said air to the user, the improvement wherein said first valve includes:
  • valve body formed with an inlet connectable with said cylinder with a passage connected to said inlet, with a valve chamber communicating with said passage, and an outlet connected with said second valve:
  • piston means axially displaceable in said body and including a valve member engageable with said seat and movable toward and away from said seat for blocking and unblocking communication between said passage and said valve chamber, said piston means defining within said body a first compartment expandable with movement of said valve member away from said seat and communicating with the ambient environment, and a second compartment expandable with movement of said valve member toward said seat, said valve member being provided with a port communicating with said passage in a blocking position of said valve member and with a bore extending in the direction of displace ment of said valve member and communicating with said port;
  • valve member received in said bore and defining therein a piston chamber expanding and contracting with movement of said valve member toward and away from said seat, respectively, and communicating with said valve chamber via said port in an unblocking position of said valve member and communicating with said cylinder via said port in a blocking position of said valve member, said valve member being formed with a further passage connecting said valve member with said second compartment in all positions of said valve member:
  • valve body is provided with a cap defining said compartments with said piston means, said plunger bearing against said cap, said piston means having a piston sealingly and slidably engaging said cap, further seal means between said valvemember and said valve body and between said plunger and said valve member, said plunger being formed in said piston chamber of said valve means with an effective surface area equal to that of the valve seat.

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  • Physics & Mathematics (AREA)
  • Health & Medical Sciences (AREA)
  • Automation & Control Theory (AREA)
  • Fluid Mechanics (AREA)
  • General Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Pulmonology (AREA)
  • Business, Economics & Management (AREA)
  • Emergency Management (AREA)
  • General Health & Medical Sciences (AREA)
  • Respiratory Apparatuses And Protective Means (AREA)
  • Control Of Fluid Pressure (AREA)
  • Self-Closing Valves And Venting Or Aerating Valves (AREA)

Description

United States Patent [72] Inventor: Leszek Suchy Gdansk, Poland [21] Application No.: 687,763
[22] Filed: Dec. 4,1967
[45] Patented: Aug. 4, 1970 [73] Assi'gnee: Zaklady Mechaniki Precyzjnej- Przedziebiorst-wo Panstwowe, Gdansk-Oliwa, Poland, 'a Corp. of Poland [32] Priority: Dec. 12,1966
[33] Poland [31] No; P117924 [54] PRESSURE-REDUCING VALVE FOR BREATHING APPARATUS 2 Claims, 1 Drawing Fig. 1
[52] U.S.Cl. 137/494, l37/505.18, SOS-.28, 505.12
AMBlENT ENVIRONMENT [50] Field ofSearch ..l37/505.l8,
I [56] References 011611 UNITED STATES PATENTS 2,855,950 10/1958 Phillips 137/50523 3,211,175 10/1965 Replogle l37/505.28XR 3,227,172 1/1966 Sims 137/505.l8XR 3,250,292 5/1966 Mollick... l37/505.28 3,389,796 6/1968 Flala 137/509XR Primary Examiner-Harold W. Weakley Altorney- Karl F. Ross ABSTRACT: A pressure-reducing valve for breathing apparatus provided with a piston fitted inside a movable piston terminating in a valve head closing the seat of the conduit feeding the air from the air cylinder, where the area of the piston equals the area ofthe throttle port ofthe seat.
BREATHING i6 APPARATUS SECOND VALVE (LUNG CONTROL) COMPRESSED -AlR CYLINDER Patented Aug. 4, 1970 3,522,818
9 10 11\ 12\ 13 14 M45 8) g /16 ZEEZEQ'TTFS SECOND VALVE (LUNG CONTROL) COMPRESSED -A\R CYLINDER Leszek SUCHY IXVENTOR.
PRESSURE-REDUCING VALVE FOR BREATHING APPARATUS BACKGROUND OF THE INVENTION The invention relates to a pressure-reducing valve of the first stage for a breathing apparatus provided with a two-stage pressure reducing system, which is able to maintain a constant average pressure independently of the pressure existing in the gas cylinder.
There is known a breathing apparatus in which the compressed air coming from the cylinder is reduced to the breathing pressure by means of two pressure-reducing valves. The first valve reduces the high pressure of the air coming from the air-supply cylinder to the intermediate pressure, which mostly does not exceed 8 atmospheres (atm). The second valve, controlled by the lung of the user reduces this pressure to a breathing pressure. The pressure reducing valves of the first stage of known devices have the essential disadvantage that they do not ensure a constant intermediate pressure, which increases as the pressure in the cylinder drops.
Simplifying the matter somewhat it may be assumed, that the increase of the intermediate pressure depends only on the area ofthe throttling hole. The higher pressure ofthe air coming from the cylinder upon the valve head of the pressurereducing valve effects a more intensive increase of the intermediate pressure. These variations cause varied breathing resistances and disadvantageously .influence -the breathing characteristic of the device. Use of the throttling hole of small area eliminates these disadvantages to some extent, but causes strong throttling of the flow at high demand of the air. I
There are also known pressure-reducing valves which assure maintenance of the constant intermediate pressure, but they are characterized by their complicated and not readily manufactured structure.
SUMMARY OF THE INVENTION The pressure-reducing valve according to the invention has a simplified structure and permits use of a throttling hole of large cross-sectional area and able to cover any demand on air, and it simultaneously secures the constant intermediate pressure, independently of the pressure in the cylinder.
The task set in order to eliminate said inconveniences is, according to the invention, accomplished in such manner that the force acting unilaterally on the valve head and effecting the increase of the reduced intermediate pressure at decreasing pressure in the cylinder is eliminated; The valve head is relieved by a force arising from the pressure of the air penetrating through a hole made in the valve head into the space closed by the piston, the latter being movable against the valve head and having an area equal to the area of thethrottling hole, so that the valve head is in stability.
BRIEF DESCRIPTION OF THE DRAWING The pressurereducing valve is more thoroughly explained by means of an exemplary embodiment in the accompanying drawing, the sole FIG U RE of which is a longitudinal sectional 1 view of the valve.
DESCRIPTION OF THE PREFERRED EMBODIMENT The pressure-reducing valve consists of a valve body 1, a
' nutfastening the valve to the cylinder 3, a seat 4 with the "throttling hole, a chamber of the valve head 6 connected with a pistonrod 6 and a piston 11, a spring 10 opening the valve, a
cover 'l2fof the body, a piston 16, and seals l5, l7 and 19 closing the spaces 13, 21 and a chamber 5. In the cover 12 there 'are'made ports 8 leading the environmental (ambient) pres- The described design may be used for breathing apparatus destined for moving under water, as well as for a paratus insulating the human breathing system from gases 0 the environment.
The mode of operation of the valve according to the invention is as follows:
Before supplying the compressed air from the cylinder, the pressure of the spring 10 upon the piston 11 holds the valve head 6 open. After influx, the air flows from the cylinder through the conduit 2 and the chamber 5 to the conduit 20, which leads the air to the breathing apparatus. The air penetrates also through the hole l8 and the slot 14 to the space 13 above the piston ll. As the suitable value of the reduced pressure is achieved, the pressure of the air upon the piston Ill overcomes the resistance of the spring 10, causes a shifting of the piston, and closes the seat 4. Simultaneously through the hole 22 the air flows to the space 21 closed by the piston 16 abutting against the cover 12 of the valve body, creating thereby the fixed position of the piston 16 in relation to the valve seat 4.
Iclaim:
I. In a breathing apparatus comprising a compressed-air tank, a first valve connected to said tank for producing air at a constant intermediate pressure less than that in said cylinder, a second valve connected to said first valve for converting air at said intermediate pressure into air at breathing pressure, and a breathing device connected to said second valve for supplying said air to the user, the improvement wherein said first valve includes:
a valve body formed with an inlet connectable with said cylinder with a passage connected to said inlet, with a valve chamber communicating with said passage, and an outlet connected with said second valve:
means in said valve chamber forming a valve seat around said passage:
piston means axially displaceable in said body and including a valve member engageable with said seat and movable toward and away from said seat for blocking and unblocking communication between said passage and said valve chamber, said piston means defining within said body a first compartment expandable with movement of said valve member away from said seat and communicating with the ambient environment, and a second compartment expandable with movement of said valve member toward said seat, said valve member being provided with a port communicating with said passage in a blocking position of said valve member and with a bore extending in the direction of displace ment of said valve member and communicating with said port;
a plunger received in said bore and defining therein a piston chamber expanding and contracting with movement of said valve member toward and away from said seat, respectively, and communicating with said valve chamber via said port in an unblocking position of said valve member and communicating with said cylinder via said port in a blocking position of said valve member, said valve member being formed with a further passage connecting said valve member with said second compartment in all positions of said valve member: and
a spring bearing upon said piston means and yieldably resisting contraction of said first compartment.
2. The improvement defined in claim I wherein said valve body is provided with a cap defining said compartments with said piston means, said plunger bearing against said cap, said piston means having a piston sealingly and slidably engaging said cap, further seal means between said valvemember and said valve body and between said plunger and said valve member, said plunger being formed in said piston chamber of said valve means with an effective surface area equal to that of the valve seat.
US687763A 1966-12-12 1967-12-04 Pressure-reducing valve for breathing apparatus Expired - Lifetime US3522818A (en)

Applications Claiming Priority (1)

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PL117924A PL55641B1 (en) 1966-12-12

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US (1) US3522818A (en)
DE (1) DE1708117C3 (en)
FR (1) FR1548799A (en)
GB (1) GB1204356A (en)
SE (1) SE330130B (en)

Cited By (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3866622A (en) * 1972-03-18 1975-02-18 Kawasaki Heavy Ind Ltd Open circuit breathing apparatus
US4041978A (en) * 1975-01-20 1977-08-16 Scubapro Eu Pressure regulator for breathing apparatus
US4119294A (en) * 1975-10-02 1978-10-10 Jos. Schneider & Co. Optische Werke Pressure-regulating valve
US4146275A (en) * 1977-10-11 1979-03-27 Elliott Robert H Residual pressure relief valve for brakes
US4652216A (en) * 1984-05-21 1987-03-24 Allied Corporation Compressor inlet control device
WO1992022859A1 (en) * 1991-06-13 1992-12-23 Allied-Signal, Inc. Redundant pressurizing valve
WO1996019761A1 (en) * 1996-01-11 1996-06-27 Harsco Corporation Eductive pressure regulator
US5662100A (en) * 1996-01-11 1997-09-02 Harsco Corporation Eductive pressure regulator
GB2389641A (en) * 2002-04-27 2003-12-17 Draeger Aerospace Gmbh Reducing valve for gas under pressure
US20040231727A1 (en) * 2001-11-13 2004-11-25 Kabushiki Kaisha Kawasaki Precision Machinery Pressure reducing valve
US20040250857A1 (en) * 2001-09-07 2004-12-16 Ernst Bernhard Reducing valve for compressed gas bottles
US7712482B2 (en) 2007-06-07 2010-05-11 Kabushiki Kaisha Kawasaki Precision Machinery Pressure-reducing valve
CN107854784A (en) * 2017-01-20 2018-03-30 湖北航天化学技术研究所 A kind of oxygen breathing apparatus oxygen cylinder pile-up valve

Families Citing this family (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3762604A (en) * 1971-05-10 1973-10-02 D Shonerd Survival support device
US4243031A (en) * 1978-12-18 1981-01-06 Abbott Laboratories Intravenous pump filter protector
EP0112765A1 (en) * 1982-12-20 1984-07-04 Litton Systems, Inc. Combined pressure-reducing regulator and shutt-off valve
GB2182421B (en) * 1985-09-11 1989-09-20 Actrol Ind Pty Ltd Pressure control valve
AU581536B2 (en) * 1985-09-11 1989-02-23 Actrol Industries Pty. Ltd. Pressure control valve
GB2269441B (en) * 1992-08-05 1996-01-24 Sabre Safety Ltd A gas flow control regulator
WO2003093708A1 (en) 2002-05-06 2003-11-13 Walter George Morrison Pressure control valve

Cited By (17)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3866622A (en) * 1972-03-18 1975-02-18 Kawasaki Heavy Ind Ltd Open circuit breathing apparatus
US4041978A (en) * 1975-01-20 1977-08-16 Scubapro Eu Pressure regulator for breathing apparatus
US4119294A (en) * 1975-10-02 1978-10-10 Jos. Schneider & Co. Optische Werke Pressure-regulating valve
US4146275A (en) * 1977-10-11 1979-03-27 Elliott Robert H Residual pressure relief valve for brakes
US4652216A (en) * 1984-05-21 1987-03-24 Allied Corporation Compressor inlet control device
WO1992022859A1 (en) * 1991-06-13 1992-12-23 Allied-Signal, Inc. Redundant pressurizing valve
GB2271414A (en) * 1991-06-13 1994-04-13 Allied Signal Inc Redundant pressurizing valve
GB2271414B (en) * 1991-06-13 1994-10-19 Allied Signal Inc Redundant pressurizing valve
WO1996019761A1 (en) * 1996-01-11 1996-06-27 Harsco Corporation Eductive pressure regulator
US5662100A (en) * 1996-01-11 1997-09-02 Harsco Corporation Eductive pressure regulator
US20040250857A1 (en) * 2001-09-07 2004-12-16 Ernst Bernhard Reducing valve for compressed gas bottles
US20040231727A1 (en) * 2001-11-13 2004-11-25 Kabushiki Kaisha Kawasaki Precision Machinery Pressure reducing valve
GB2389641A (en) * 2002-04-27 2003-12-17 Draeger Aerospace Gmbh Reducing valve for gas under pressure
GB2389641B (en) * 2002-04-27 2004-07-28 Draeger Aerospace Gmbh Reducing valve for gas under pressure
US7121298B2 (en) 2002-04-27 2006-10-17 DRäGER AEROSPACE GMBH Reducer valve for pressurized gas
US7712482B2 (en) 2007-06-07 2010-05-11 Kabushiki Kaisha Kawasaki Precision Machinery Pressure-reducing valve
CN107854784A (en) * 2017-01-20 2018-03-30 湖北航天化学技术研究所 A kind of oxygen breathing apparatus oxygen cylinder pile-up valve

Also Published As

Publication number Publication date
DE1708117B2 (en) 1973-06-28
DE1708117C3 (en) 1974-01-31
SE330130B (en) 1970-11-02
DE1708117A1 (en) 1971-04-22
GB1204356A (en) 1970-09-09
FR1548799A (en) 1968-12-06

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