US3646933A - Pneumatic respirator comprising a fluid-operated alternating changeover switch - Google Patents

Pneumatic respirator comprising a fluid-operated alternating changeover switch Download PDF

Info

Publication number
US3646933A
US3646933A US3646933DA US3646933A US 3646933 A US3646933 A US 3646933A US 3646933D A US3646933D A US 3646933DA US 3646933 A US3646933 A US 3646933A
Authority
US
United States
Prior art keywords
chamber
respirator
pressure
valve
gas
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
Other languages
English (en)
Inventor
Jean-Pierre Monnier
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.)
Air Liquide SA
LAir Liquide SA pour lEtude et lExploitation des Procedes Georges Claude
Original Assignee
Air Liquide SA
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 Air Liquide SA filed Critical Air Liquide SA
Application granted granted Critical
Publication of US3646933A publication Critical patent/US3646933A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61M—DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY; DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY; DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR
    • A61M16/00—Devices for influencing the respiratory system of patients by gas treatment, e.g. ventilators; Tracheal tubes
    • 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
    • Y10T137/206—Flow affected by fluid contact, energy field or coanda effect [e.g., pure fluid device or system]

Definitions

  • ABSTRACT Pneumatic respirator comprising two stages in series.
  • the first stage is a pneumatically operated changeover gas switch an exit of which is connected to a chamber the volume of which may be varied in order to vary the alternation frequency of the switch.
  • the pressure inside the chamber actuates a valve which alternately opens and closes a passage between the respiratory passages of the patient and the source of gas to be insufflated,
  • the present invention relates to a pneumatic respirator comprising a fluid-operated alternating changeover switch and, on one of the outlets of the said switch, an. adjustablevolume chamber for varying the alternating frequency of the switch.
  • a switch controlling the ratio between the phase times is connected to the adjustable-volume chamber by a valve the degree of opening of which controls the ratio between the time periods of throughflow of the fluid in the two outlets of the ratio-controlling switch.
  • the latter in its turn controls, preferably by way of an amplifier switch, a valve which opens and closes the passage of the gas to be insufflated alternately; this valve may be a fluid-operated changeover switch, of small bulk but allowing the gas to be insufflated to escape to the free atmosphere during the exhalation periods of the patient.
  • This valve may also be of the usual pneumatic-actuation type.
  • This three-stage or four-stage apparatus is fairly complex, which increases the risks of failure. Furthermore, the adjustment of the valve controlling the ratio between the time periods of passage through the two outlets is very tricky; it is scarcely possible to effect this adjustment anywhere except at the factory, which prevents adjusting this ratio during use.
  • the respirator according to the invention does not have these disadvantages; it is characterized in that the pressure in the said chamber controls a pneumatic-actuation valve which, by means of its closure member, opens or closes a passage between the respiratory passages of the patient and the source of the gas which is to be insufflated.
  • the ratio between times is easily adjusted by means which are easy to set, acting on one or more means controlling the triggering pressure of the pneumatic-actuation valve; examples are described hereinafter.
  • Another advantage of the respirator according to the invention is that it permits controlling the ratio between the time periods of the inhalation and exhalation phases independently of the control of frequency.
  • FIG. 1 shows a first form ofembodiment.
  • FIG. 2 shows how the pressure in the variable-volume chamber varies as a function of time.
  • FIG. 3 shows a modified form of embodiment according to FIG. 1.
  • FIG. 4 shows in more detail a valve for carrying the invention into effect.
  • FIG. I there is illustrated diagrammatically at 2 a fluidoperated alternating changeover switch which is a bistable cell whose control orifices are closed.
  • the gas actuating this changeover switch arrives by way of a duct 4 and passes alternately into an outlet duct 6 the end of which is connected to the free atmosphere, and into another outlet duct 8 debouching into a variable space 10.
  • a cell of this type is described in French Pat. No. 1,568,831.
  • the duct 8 is also connected by a tube 12 to a chamber 14 of a pneumatically actuated valve 16.
  • the space is contained in a cylinder 18 and bounded by a piston 20 the position of which can be adjusted by a knob 22.
  • the displacement of the piston modifies the operating frequency of the changeover switch 2 by modifying the volume of the adjustable-volume chamber to which the outlet 8 of the alternating changeover switch is connected; this volume includes not only the space 10 but also the internal volumes of the duct 8, the tube 12 and the volume of the chamber 14.
  • the valve 16 contains a diaphragm 24 which separates the chamber 14 from another chamber 26 communicating with the atmospheric air by an orifice 28.
  • the diaphragm actuates, by means of a rod 30, a valve head 32 cooperating with a seat 34 to constitute the closure member of the valve.
  • the rod passes through a sealing ring 36.
  • the gas to be insufflated arrives by way of a union 38, passes through the valve 32, 34 when it isopen, andissues through a union 40 towards the mask worn by the patient.
  • the valve is open when the pressure in the chamber 14, and therefore in the space 10, is sufficient.
  • valve head and consequently the diaphragm, are pushed by aspring 42 in, the direction opposite to the action on the diaphragm of the pressure in the chamber 14.
  • the spring is pushed by a plate 44 which terminates a screw 46 provided with an operating-knob 48.
  • This screw is in engagement with an internally.screw-threaded hole in the bottom wall 50 of the valve; it permits the spring to be given a more or less considerable compression.
  • the curve 54 shows how the pressure in the volume 10 varies in accordance with time, owing to the operation of the alternating changeover switch 2. This curve is valid for a certain apparatus and a certain value for the adjustable volume.
  • the abscissae are graduated in seconds and the ordinates in mil- Iibars.
  • the opening time periods are those between the times corresponding to the points 56 and 58, between the points 60 and 62, etc., or about 2 seconds each: during these time periods, the pressure in the space 10 is sufficient to keep the member 32, 34 open.
  • the closing time periods are those between the times corresponding to the points 58 and 60, etc., or about 3 seconds. The ratio between these time periods is, therefore, for the setting of the spring which gives Po as the opening'pressure, equal to 2:3.
  • the exhalation of the patient can be effected by an automatic valve arranged on the mouthpiece by which the patient is connected to the respirator.
  • FIG. 3 shows a variant wherein the opening and closing pressures of the closure member (not shown) of the valve are modified by subjecting to an adjustable pressure the chamber 26 of the pneumatic-actuation valve 76.
  • the spring 42 is adjusted at the factory in order to give, for example, a ratio of time periods equal to unity, which is the maximum which would be desirable in practice.
  • the pressure in the chamber 26 is supplied by a gas arriving through a tube 78 and expanded to the suitable value by an adjustable expansion valve 80.
  • a manometer 82 measures the pressure which thus completes the action of the spring 42; it is useful to graduate it in ratios of time periods, but then regulation of the spring by the user should not be permitted.
  • a small orifice 84 in the wall of the chamber 26 creates a slight leakage so that the movement of the diaphragm substantially does not change the pressure in the chamber, and so that the pressure in the chamber 26 can be lowered.
  • FIG; 4 shows a form of embodiment of the valve 76 in more detail.
  • the diaphragm 24 separates two chambers 14, 26 formed in plates 86, 88 clamped on the diaphragm by screws 90, 92; the chamber 14 is screwed to the tube 12 by a union 94 and the chamber 26 is connected by a screwthreaded orifice 96 to the outlet of the expansion valve 80, and to a small vent not illustrated here.
  • a rod 98 is coupled to two plates 100, 102 surrounding the central zone of the diaphragm; it widens into a valve head 104 and a sleeve 106 which guides the spring 42. In the body of the valve there is fitted a valve seat 108 cooperating with the head 104.
  • the spring bears on the one hand against the end of its guide and on the other hand against an abutment 110 which can be displaced by a screw 112. If it is desired that the variation of the ratio of time periods cannot be effected by the user except by varying the pressure of gas below the diaphragm, access to the screw 112 and to its possible control knob is prevented.
  • the source of gas to be insufi'lated for example an expansion valve supplied by a cylinder of compressed air, is connected to the valve 76 by a screw-threaded orifice 114. If the head of the valve is detached from its seat, it allows the passage of gas which, through another screw-threaded orifice 116, issues from the valve and is directed towards the patient by a tube not shown here.
  • Sealing rings 118, 120 guide the tail 122 of the plate 102 and the sleeve 106 in sealing-tight manner.
  • the outer diameter of the sleeve is equal to the diameter of the head 104 so that the closure member 104, 108 is balanced when it is closed, as regards the upstream pressure.
  • the diameter of the tail 122 of the plate 102 on which the sealing ring 118 bears is equal to the diameter of the head 104 so that the closure member 104, 108 is balanced when it is closed, as regards the downstream pressure.
  • a duct 124 provides communication between the latter and the space within the sleeve 106 and, by the slight clearance about the abutment 110, with the portion of the sleeve which is situated below the sealing ring 120.
  • the respirator according to the invention can be constructed in ways different from those described.
  • the changeover switch 2 can be of a type disclosed in French Pat. No. 1,530,662.
  • Union 94 may be connected to an auxiliary source of gas with an output limited for example by throttling, said gas escaping from chamber 14 through a valve which is controlled by the pressure inside chamber 10.
  • Pneumatically controlled valves of other types may be used; the spring 42 may be dispensed with if an auxiliary gas pressure is already used for varying the ratio of the time periods.
  • the respirator according to the invention may be used for any automatic fluid distribution system whose cycle time period and ratio between opening and closing times are to be capable of being easily adjusted; for example, it may be used for the periodic control of a jack.
  • a pneumatic respirator comprising a fluid-operated changeover switch having a plurality of outlets, a source of operating gas connected to the input of said changeover switch, a chamber communicating with one of said outlets, means to adjust the volume of the chamber for regulating the frequency of alternation of the changeover switch, a second source of gas to be insufflated, a mask to be worn by the patient, and a valve having passage means connecting the source of gas to be insufflated and said mask comprising a pneumatic actuation means having a closure member that opens and closes said passage between said mask and the source of gas to be insufflated, said chamber communicating directly and only with said one outlet and with said pneumatic actuation means.
  • a respirator as claimed in claim 1 and a spring in said valve acting on said closure member in the opposite sense to the pressure in the chamber.
  • a respirator as claimed in claim 1 and auxiliary means to exert fluid pressure on said closure member in addition to the pressure of said chamber.
  • said force-varying means including indicia to indicate the ratios between the inhalation and exhalation time periods for various adjusted positions of said force-varying means.
  • a respirator as claimed in claim 2 and auxiliary means to exert fluid pressure on said closure member in addition to the pressure of said chamber.

Landscapes

  • Health & Medical Sciences (AREA)
  • Emergency Medicine (AREA)
  • Pulmonology (AREA)
  • Engineering & Computer Science (AREA)
  • Anesthesiology (AREA)
  • Biomedical Technology (AREA)
  • Heart & Thoracic Surgery (AREA)
  • Hematology (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Animal Behavior & Ethology (AREA)
  • General Health & Medical Sciences (AREA)
  • Public Health (AREA)
  • Veterinary Medicine (AREA)
  • Respiratory Apparatuses And Protective Means (AREA)
US3646933D 1969-03-25 1970-03-24 Pneumatic respirator comprising a fluid-operated alternating changeover switch Expired - Lifetime US3646933A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
FR6908694A FR2036765A1 (forum.php) 1969-03-25 1969-03-25

Publications (1)

Publication Number Publication Date
US3646933A true US3646933A (en) 1972-03-07

Family

ID=9031206

Family Applications (1)

Application Number Title Priority Date Filing Date
US3646933D Expired - Lifetime US3646933A (en) 1969-03-25 1970-03-24 Pneumatic respirator comprising a fluid-operated alternating changeover switch

Country Status (4)

Country Link
US (1) US3646933A (forum.php)
JP (1) JPS499517B1 (forum.php)
FR (1) FR2036765A1 (forum.php)
GB (1) GB1301545A (forum.php)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6397844B1 (en) * 1998-04-23 2002-06-04 Barnwell Investments S.A. Respiration apparatus
WO2005023352A1 (en) * 2003-09-05 2005-03-17 Smiths Group Plc Valves
US20100012126A1 (en) * 2008-07-18 2010-01-21 Iph Establishment Device for removing pulmonary secretions

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CA658335A (en) * 1963-02-26 Gilroy John Respirator apparatus and method
US3496956A (en) * 1963-06-25 1970-02-24 Bendix Corp Pulse shaper
US3522816A (en) * 1969-01-30 1970-08-04 George S Springer Fluid system for filling and emptying an enclosure
US3565564A (en) * 1968-03-21 1971-02-23 Bertin & Cie Fluidic appliance for alternately filling and emptying an enclosure

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CA658335A (en) * 1963-02-26 Gilroy John Respirator apparatus and method
US3496956A (en) * 1963-06-25 1970-02-24 Bendix Corp Pulse shaper
US3565564A (en) * 1968-03-21 1971-02-23 Bertin & Cie Fluidic appliance for alternately filling and emptying an enclosure
US3522816A (en) * 1969-01-30 1970-08-04 George S Springer Fluid system for filling and emptying an enclosure

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6397844B1 (en) * 1998-04-23 2002-06-04 Barnwell Investments S.A. Respiration apparatus
WO2005023352A1 (en) * 2003-09-05 2005-03-17 Smiths Group Plc Valves
US20060249209A1 (en) * 2003-09-05 2006-11-09 Ben Jonathan K Valves
US20100012126A1 (en) * 2008-07-18 2010-01-21 Iph Establishment Device for removing pulmonary secretions
US8584675B2 (en) * 2008-07-18 2013-11-19 Iph Establishment Device for removing pulmonary secretions

Also Published As

Publication number Publication date
JPS499517B1 (forum.php) 1974-03-05
GB1301545A (forum.php) 1972-12-29
FR2036765A1 (forum.php) 1970-12-31

Similar Documents

Publication Publication Date Title
US3756229A (en) Ventilator
US3783891A (en) Balanced regulator second stage
US3795257A (en) Demand valve assembly for use with breathing or resuscitation equipment
US2552595A (en) Oxygen demand breathing system, including means for automatic altitude regulation
US2596178A (en) Pressure responsive regulator
US3830257A (en) Air-gas mixture metering device, notably for respiratory mask
US4367767A (en) Servo-controlled gas pressure relief valve
US4917144A (en) Modulating pilot operated safety relief valve for low pressure application
US3070108A (en) Balance diaphragm regulator valve
US3695263A (en) Closed circuit medical respirators
US3646933A (en) Pneumatic respirator comprising a fluid-operated alternating changeover switch
US4452242A (en) Respirator for use in pressure chambers
US3425442A (en) Pressure regulator
US2378468A (en) Pressure regulator
US3329158A (en) Balanced, single stage-single hose regulator
US2816561A (en) Pressure reducing valve
US3077881A (en) High altitude suit and mask oxygen regulator
US2310189A (en) Aircraft breathing regulator
US3181547A (en) Pneumatic transmitters
US2988085A (en) Breathing apparatus
US2441216A (en) Oxygen demand regulator
JPS586169B2 (ja) 圧力調整弁
US3638670A (en) Low to high fluid pressure interface apparatus
US2843120A (en) Regulating mechanism for inhalation and exhalation with apparatus for supplying oxygen
GB777838A (en) Improvements in or relating to an actuator mechanism