GB2144334A - Combination venturi jet and exhalation valve assembly - Google Patents

Combination venturi jet and exhalation valve assembly Download PDF

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Publication number
GB2144334A
GB2144334A GB08321182A GB8321182A GB2144334A GB 2144334 A GB2144334 A GB 2144334A GB 08321182 A GB08321182 A GB 08321182A GB 8321182 A GB8321182 A GB 8321182A GB 2144334 A GB2144334 A GB 2144334A
Authority
GB
United Kingdom
Prior art keywords
venturi
port
passage
nozzle
valve assembly
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.)
Granted
Application number
GB08321182A
Other versions
GB2144334B (en
GB8321182D0 (en
Inventor
Forrest M Bird
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.)
Bird F M
Original Assignee
Bird F M
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
Priority to SE8304235A priority Critical patent/SE437768B/en
Application filed by Bird F M filed Critical Bird F M
Priority to GB08321182A priority patent/GB2144334B/en
Priority to FR8313034A priority patent/FR2550453B1/en
Priority to DE19833329485 priority patent/DE3329485A1/en
Priority to IT22576/83A priority patent/IT1163915B/en
Publication of GB8321182D0 publication Critical patent/GB8321182D0/en
Publication of GB2144334A publication Critical patent/GB2144334A/en
Application granted granted Critical
Publication of GB2144334B publication Critical patent/GB2144334B/en
Expired legal-status Critical Current

Links

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. mouth-to-mouth respiration; Tracheal tubes
    • A61M16/20—Valves specially adapted to medical respiratory devices
    • 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. mouth-to-mouth respiration; Tracheal tubes
    • 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. mouth-to-mouth respiration; Tracheal tubes
    • A61M16/0003—Accessories therefor, e.g. sensors, vibrators, negative pressure
    • A61M16/0009—Accessories therefor, e.g. sensors, vibrators, negative pressure with sub-atmospheric pressure, e.g. during expiration
    • A61M16/0012—Accessories therefor, e.g. sensors, vibrators, negative pressure with sub-atmospheric pressure, e.g. during expiration by Venturi means
    • 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. mouth-to-mouth respiration; Tracheal tubes
    • A61M16/10—Preparation of respiratory gases or vapours
    • A61M16/12—Preparation of respiratory gases or vapours by mixing different gases
    • A61M16/122—Preparation of respiratory gases or vapours by mixing different gases with dilution
    • A61M16/125—Diluting primary gas with ambient air
    • A61M16/127—Diluting primary gas with ambient air by Venturi effect, i.e. entrainment mixers
    • 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. mouth-to-mouth respiration; Tracheal tubes
    • A61M16/20—Valves specially adapted to medical respiratory devices
    • A61M16/201—Controlled valves
    • A61M16/206—Capsule valves, e.g. mushroom, membrane valves
    • 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. mouth-to-mouth respiration; Tracheal tubes
    • A61M16/20—Valves specially adapted to medical respiratory devices
    • A61M16/208—Non-controlled one-way valves, e.g. exhalation, check, pop-off non-rebreathing valves
    • A61M16/209—Relief valves
    • 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. mouth-to-mouth respiration; Tracheal tubes
    • A61M16/0096—High frequency jet ventilation
    • 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
    • A61M2202/00—Special media to be introduced, removed or treated
    • A61M2202/02—Gases
    • A61M2202/0208—Oxygen

Landscapes

  • Health & Medical Sciences (AREA)
  • Pulmonology (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Public Health (AREA)
  • Anesthesiology (AREA)
  • Biomedical Technology (AREA)
  • Heart & Thoracic Surgery (AREA)
  • Hematology (AREA)
  • Emergency Medicine (AREA)
  • Animal Behavior & Ethology (AREA)
  • General Health & Medical Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Veterinary Medicine (AREA)
  • Respiratory Apparatuses And Protective Means (AREA)
  • Measurement Of The Respiration, Hearing Ability, Form, And Blood Characteristics Of Living Organisms (AREA)
  • Sampling And Sample Adjustment (AREA)
  • Nozzles (AREA)
  • Percussion Or Vibration Massage (AREA)
  • Infusion, Injection, And Reservoir Apparatuses (AREA)

Abstract

A jet ventilator (816) comprises a main body (817) with a passage (818) having an patent port (823), an expiratory port (819) and an entrainment port (848). The passage (818) is closed off by a cap (858) having a jet inlet (864). A diaphragm (861) extends across the passage (818). A body (826) having a venturi-like passageway (833) is slidably mounted in the passage (818). A nozzle (851) provides communication between the inlet (864) and the venturi-like passageway (833) and is connected to the venturi body such that when gas is supplied to the inlet, the venturi body (826) is caused by the pressure on the diaphragm (861) to move to a position against seat (838) against the action of a spring (841). <IMAGE>

Description

SPECIFICATION Combination Venturi Jet and Exhalation Valve Assembly This invention relates to a combination venturi jet and exhalation valve assembly for use in a ventilator.
Heretofore shrouded venturi assemblies and exhalation valve assemblies have been provided in ventilators. However, there is a need for improved shrouded venturi assemblies and exhalation valve assemblies and particularly a need for a combination of the same.
In general it is an object of the present invention to provide an assembly of the above character which makes possible high frequency oscillation with maximum stroke volume.
Another object of the invention is to provide an assembly of the above character which makes possible rapid opening and closing of the expiratory port.
Another object of the invention is to provide an assembly of the above character which has minimal dead space to minimize rebreathing of gases.
Another object of the invention is to provide an assembly of the above character which can be operated from a single power source.
Another object of the invention is to provide an assembly of the above character which upon failure of the power source assumes a fail-safe position.
Another object of the invention is to provide an assembly of the above character which is relatively quiet in operation.
Additional objects and features of the invention will appear from the following description in which a preferred embodiment is set forth by way of example in conjunction with the accompanying drawing.
In the drawing there is disclosed a cross sectional view of a pneumatic combination venturi jet and exhalation valve assembly incorporating the invention which can be utilized with various types of ventilators used for ventilating the lungs of mammals.
The combination venturi jet and exhalation valve assembly 816 as shown in the drawing consists of a generally cylindrical hollow body 817 which has a cylindrical passage 81 8 extending therethrough. An expiratory outlet 819 is mounted in the body 817 and is in communication with the passage 818. An additional outlet 821 is in communication with the passage 818 and is mounted in the body to extend diametrically therefrom and is utilized for sampling the airway pressure within the passage 818. The outlet 821 as shown is threaded into the body 817 and an O-ring 822 is provided to form an air-tight seal with the body. The passage 81 8 terminates in a proximal airway port 823 which is adapted to receive a suitable patient adapter such as a mouthpiece or endotracheal tube to be connected into the patient airway.A generally cylindrical venturi body 826 is provided and is sized in such a manner so that it can be slidably mounted within the passage 818 of the body 817. The body 817 is mounted within a cylindrical venturi bushing 827 in such a manner so that the bushing 827 moves with the venturi body 826. The venturi body 826 is provided with an annular flange 828 at its forward extremity which engages the forward extremity of the bushing 827. It is also provided with a centrally disposed annular flange 829 which also frictionally engages the bushing 827. At its rearmost extremity, the body 826 is provided with another annular flange 831 which engages a lip 832 that is L-shaped in cross section provided on the rear extremity of the bushing 827.The venturi body 826 is provided with a venturi-like passageway 833 which extends axially of the venturi body and opens through both ends of the venturi body 826. The forward extremity of the venturi body is provided with a chamber 834 in which a main inner groove 836 is provided and in which there is seated an O-ring 837. The O-ring 837 serves as a valve member and is adapted to engage a conical valve seat 838 which is formed in the body 817 immediately ahead of the expiratory outlet 819.
Means is provided for yieldably urging the venturi body 826 with its associated bushing 827 to a position so that the O-ring valve member 837 is moved out of engagement with the valve seat 838 and consists of a helical spring 841 which has one end seated against the lip 832 provided on the bushing 827 and has the other end engaging an annular abutment 842 formed in the venturi body 826.
The venturi body 826 is provided with a cylindrical threaded end 844 which has threaded thereon a cylindrical cap 846 which has portions of the same cut away to provide openings 847 which are in communication with an inlet 848 mounted in the body 817 and also in communication with the passage 818. The remaining portions of the cap 846 form L-shaped legs 849 which serve to support a nozzle 851 in a position so that a centrally disposed passage 852 extending therethrough is in axial alignment with the axis of the venturi-like passageway 833 provided in the venturi body 826. A nozzle or jet 851 is provided within the larger cylindrical bore 853 in axial alignment with the passage 852. An annular recess 854 is formed in the bore 853 and carries an O-ring 856. An end cap 858 is threaded into the outermost rear extremity of the body 817.An annular recess 859 is provided in the body 817 and receives the outer annular margin of diaphragm 861 formed of a suitable material such as neoprene. The diaphragm 861 extends across the inner face of the end cap 858 and carries a hollow diaphragm stem 862 having a flow passage 863 therein. The stem is adapted to be inserted into the bore 853 of the nozzle 851 and is adapted to establish a sealing engagement with the O-ring 856 so that an airtight seal is formed between the stem 862 and the nozzle 851. Passage 863 is in alignment and in communication with a flow passage 864 provided in the end cap 858. The end cap is provided with an inlet fitting 866 which is adapted to receive source gas under pressure in a suitable form such as periodic pulses of gas from a ventilator.
Operation of the combination venturi jet and exhalation valve assembly 816 in ventilators of the type hereinbefore described may now be briefly described as follows. Let it be assumed that the appropriate connections have been made to the exhalation valve assembly 816 from the ventilator. Thus source gas such as air, oxygen or a mixture of air and oxygen would be connected to the fitting 866 provided on the end cap 858.
The fitting 821 can be used to provide the patient airway pressure. Now let it be assumed that source gas as, for example, pulses of gases or pulsatile gases are being supplied to the inlet fitting 866. These pulsatile gases are supplied through the passage 864, through the passage 863, through the nozzle 851, through the bore 846 into the venturi-like passage 833 and thence into the patient airway. As the pressure introduced through the passage 864 overwhelms the orifice 852 provided in the nozzle 851, pressure is built up behind the diaphragm 861 to move the diaphragm with the hollow diaphragm stem 862 forwardly carrying with it the venturi body 826 with its associated bushing 827 forwardly in the body 817 until the O-ring valve member 837 engages the valve seat 838 provided in the body to close off the expiratory port or outlet 819.In this manner, the expiratory port is closed off by the application of air under pressure to the exhalation valve assembly. The advantage of the arrangement shown in the drawing is that as soon as gas is no longer supplied to the assembly 816, the spring 841 returns the sliding venturi body 826 to its rearmost position determined by the rearmost position of the valve stem carried by the diaphragm 861.
It has been found that the combination venturi jet and exhalation valve assembly 816 has numerous advantages over the combination of the shrouded venturi assembly and the exhalation valve assemblies provided in ventilators heretofore. These advantages include rapid opening and closing of the expiratory port 819 which is accomplished in view of the fact that the sliding venturi body reacts very rapidly to the changes in gas pressure behind the diaphragm 861. Thus immediately upon receipt of gas in the nozzle 851, the diaphragm is actuated to move the sliding venturi body forward to close the expiratory port 819. Conversely, as soon as gas is no longer being introduced through the nozzle 851, the spring 841 rapidly returns the sliding venturi body to its original position. This makes possible a much higherfrequency of oscillation with maximum stroke volume. Because there is low inertia in the parts forming the assembly it has been found that frequencies as high as 30 Hertz can be accomplished without getting out of phase.

Claims (7)

1. A valve assembly comprising a main body having a passage therein defining an airway port, a venturi body, means slidably mounting said venturi body in the passage, the main body being formed with an expiratory port communicating with said passage and being spaced from said airway port, the main body also being formed with an entrainment port which is in communication with said passage and which is spaced from said expiratory port, the venturi body having a venturi-like passageway extending axially therethrough, means for mounting a nozzle on the venturi body, the nozzle having an opening therein in axial alignment with the venturi-like passageway, a diaphragm carried by the main body and extending across the passage, an end cap carried by the main body and having an inlet opening therein in communication with one side of the diaphragm, means forming a connection between the diaphragm and the nozzle, means for establishing communication between the inlet in the end cap and the nozzle and extending through the diaphragm whereby when gas is supplied to the inlet, gas is supplied to the nozzle to urge the diaphragm to move the venturi body from a first to a second position, the means for mounting the nozzle on the venturi body being such as to permit the passage of air from the entrainment port into the venturi-like passageway.
2. A valve assembly as claimed in Claim 1 further comprising means for forming a seal between the venturi body and the main body, said means including valve means carried by the forward extremity of the venturi body.
3. A valve assembly as claimed in Claim 1 or Claim 2 wherein said venturi body includes a sleeve extending substantially the entire length of the venturi body.
4. A valve assembly as claimed in Claim 1, Claim 2 or Claim 3 wherein the means for mounting the nozzle includes a cap secured to the venturi body, the cap having openings therein and establishing communication between the passageway in the venturi body and the entrainment port.
5. A valve assembly as claimed in any preceding claim, further including an overpressure failsafe relief valve means connected to said entrainment port.
6. A valve assembly as claimed in any preceding claim, further including a failfsafe pulse regulator connected to the expiratory port, said failsafe pulse regulator including a port open to ambient and means for closing said port in response to gases being supplied to said nozzle.
7. A valve assembly substantially as hereinbefore described with reference to and as shown in the accompanying drawings.
GB08321182A 1983-08-02 1983-08-05 Combination venturi jet and exhalation valve assembly Expired GB2144334B (en)

Priority Applications (5)

Application Number Priority Date Filing Date Title
SE8304235A SE437768B (en) 1983-08-02 1983-08-02 Combined venturi unit and exhalation valve unit
GB08321182A GB2144334B (en) 1983-08-02 1983-08-05 Combination venturi jet and exhalation valve assembly
FR8313034A FR2550453B1 (en) 1983-08-02 1983-08-08 COMBINED ASSEMBLY WITH VENTURI DIFFUSER AND EXHALATION VALVE
DE19833329485 DE3329485A1 (en) 1983-08-02 1983-08-16 Respirator
IT22576/83A IT1163915B (en) 1983-08-02 1983-08-18 Ventilator venturi jet and exhalation valve

Applications Claiming Priority (5)

Application Number Priority Date Filing Date Title
SE8304235A SE437768B (en) 1983-08-02 1983-08-02 Combined venturi unit and exhalation valve unit
GB08321182A GB2144334B (en) 1983-08-02 1983-08-05 Combination venturi jet and exhalation valve assembly
FR8313034A FR2550453B1 (en) 1983-08-02 1983-08-08 COMBINED ASSEMBLY WITH VENTURI DIFFUSER AND EXHALATION VALVE
DE19833329485 DE3329485A1 (en) 1983-08-02 1983-08-16 Respirator
IT22576/83A IT1163915B (en) 1983-08-02 1983-08-18 Ventilator venturi jet and exhalation valve

Publications (3)

Publication Number Publication Date
GB8321182D0 GB8321182D0 (en) 1983-09-07
GB2144334A true GB2144334A (en) 1985-03-06
GB2144334B GB2144334B (en) 1986-11-26

Family

ID=51519423

Family Applications (1)

Application Number Title Priority Date Filing Date
GB08321182A Expired GB2144334B (en) 1983-08-02 1983-08-05 Combination venturi jet and exhalation valve assembly

Country Status (5)

Country Link
DE (1) DE3329485A1 (en)
FR (1) FR2550453B1 (en)
GB (1) GB2144334B (en)
IT (1) IT1163915B (en)
SE (1) SE437768B (en)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2174609A (en) * 1985-05-02 1986-11-12 Pneupac Ltd Resuscitator/ventilator
EP0234736A1 (en) * 1986-01-27 1987-09-02 Advanced Pulmonary Technologies, Inc. Variable frequency jet ventilation system
US4838259A (en) * 1986-01-27 1989-06-13 Advanced Pulmonary Technologies, Inc. Multi-frequency jet ventilation technique and apparatus
CN104812431A (en) * 2012-07-17 2015-07-29 卡尔·赖纳有限责任公司 Device for generating a pulsating gas columm
WO2023014356A1 (en) * 2021-08-05 2023-02-09 Vyaire Medical Inc. Gas valve for a ventilation apparatus and a circuit for a ventilation system

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB8511171D0 (en) * 1985-05-02 1985-06-12 Pneupac Ltd Entrainment devices
DE4345123C1 (en) * 1993-12-30 1995-04-13 Peter Dr Ing Habil Schaller Valve arrangement for a respirator device
US11793958B2 (en) 2021-03-07 2023-10-24 Oxyjet Limited Needle based precision venturi flow-generator for positive pressure ventilation

Family Cites Families (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2865368A (en) * 1954-11-26 1958-12-23 E A Baer Resuscitators
GB1138274A (en) * 1966-03-04 1968-12-27 Liston Fletcher Inc Therapeutic respirator
FR2174782B1 (en) * 1972-03-10 1975-03-21 Lafourcade Jean Michel
GB1511233A (en) * 1974-06-04 1978-05-17 Pneupac Ltd Gas valve mechanisms
US3915164A (en) * 1974-08-22 1975-10-28 Bird F M Ventilator
US3974828A (en) * 1975-01-27 1976-08-17 Bird F M Ventilator and method
US4060078A (en) * 1975-08-18 1977-11-29 Bird F M Ventilator and method
SE430304B (en) * 1980-09-01 1983-11-07 Testa Lab A S ANESTHESIA RESPIRATORY EQUIPMENT
DE3125055C2 (en) * 1981-06-26 1983-04-21 Norbert Josef 8000 München Rapp Control for ventilators

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2174609A (en) * 1985-05-02 1986-11-12 Pneupac Ltd Resuscitator/ventilator
EP0234736A1 (en) * 1986-01-27 1987-09-02 Advanced Pulmonary Technologies, Inc. Variable frequency jet ventilation system
US4747403A (en) * 1986-01-27 1988-05-31 Advanced Pulmonary Technologies, Inc. Multi-frequency jet ventilation technique and apparatus
US4838259A (en) * 1986-01-27 1989-06-13 Advanced Pulmonary Technologies, Inc. Multi-frequency jet ventilation technique and apparatus
CN104812431A (en) * 2012-07-17 2015-07-29 卡尔·赖纳有限责任公司 Device for generating a pulsating gas columm
CN104812431B (en) * 2012-07-17 2017-03-08 卡尔·赖纳有限责任公司 For producing the device of the gas column of pulsation
WO2023014356A1 (en) * 2021-08-05 2023-02-09 Vyaire Medical Inc. Gas valve for a ventilation apparatus and a circuit for a ventilation system

Also Published As

Publication number Publication date
SE8304235L (en) 1985-02-03
GB2144334B (en) 1986-11-26
DE3329485C2 (en) 1992-06-25
FR2550453B1 (en) 1989-07-13
IT1163915B (en) 1987-04-08
DE3329485A1 (en) 1985-03-07
SE8304235D0 (en) 1983-08-02
GB8321182D0 (en) 1983-09-07
SE437768B (en) 1985-03-18
IT8322576A1 (en) 1985-02-18
FR2550453A1 (en) 1985-02-15
IT8322576A0 (en) 1983-08-18

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PE20 Patent expired after termination of 20 years

Effective date: 20030804