US3456642A - Demand actuating means for alternate breathing supply - Google Patents
Demand actuating means for alternate breathing supply Download PDFInfo
- Publication number
- US3456642A US3456642A US604979A US3456642DA US3456642A US 3456642 A US3456642 A US 3456642A US 604979 A US604979 A US 604979A US 3456642D A US3456642D A US 3456642DA US 3456642 A US3456642 A US 3456642A
- Authority
- US
- United States
- Prior art keywords
- oxygen
- source
- valve
- breathing
- inspiration
- 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
Links
Images
Classifications
-
- 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
Description
DEMAND ACTUATING MEANS FOR ALTERNATE BREATHING SUPPLY Filed D80. 27, 1966 C. D. CUPP July 22, 1969 3 Sheets-Sheet 1 A R QQ bk mm Q N w N INVENTOR.
C'i'zczwzas' D Cup tr ATTORNEYS.
C. D. CUPP July 22, I96? DEMAND ACTUATING MEANS FOR ALTERNATE BREATHING SUPPLY Filed Dec, 27, 1966 3 Sheets-Sheet 2 INVENTOR. (7107193 D. Cupp BY M 62W ATTQPNEYS.
July 22, 1969 c. D. CUPP 3,456,642
DEMAND ACTUATING MEANS FOR ALTERNATE BREATHING SUPPLY Filed Dec. 27, 1966 5 Sheets-Sheet 5 m a u INVENTOR. CfzarZQa' 7). Cap
ATTORNEYS.
3,456,642 DEMAND ACTUATING MEANS FOR ALTERNATE BREATHING SUPPLY Charles D. Cupp, Lancaster, N.Y., assignor, by mesne assignments, to Automatic Sprinkler Corporation of America, Cleveland, Ohio, a corporation of Ohio Filed Dec. 27, 1966, Ser. No. 604,979 Int. Cl. A62b 7/04 U.S. Cl. 128142.2 8 Claims ABSTRACT OF THE DISCLOSURE The user is supplied with breathing fluid from a first source during normal inspiration. The inspiration effort made by the user is sensed by a control which supplies the user with breathing fluid from a normally closed second source automatically in response to an abnormally strong inspiration effort. The control includes an aneroid for turning on the second source automatically only when the ambient atmospheric pressure is below a predetermined level. A manually operable arrangement can actuate and reset the control.
BRIEF SUMMARY OF THE INVENTION The present invention relates generally to multi-source systems supplying breathing fluid to a user. More specifically, the present invention relates to an actuator in an oxygen supply system providing oxygen to the wearer of a face mask from a main oxygen source during normal inspiration, the actuator herein described being operable positively and automatically in response to an abnormally strong inspiration effort to establish communication with an auxiliary source of oxygen.
In single source oxygen systems unexpected depletion of the oxygen source or interruption of the flow of oxygen can result in serious injury or death to a user thereof in toxic, high altitude or other oxygen deficient environments. Systems having primary and secondary sources are customarily used to avoid this difliculty and usually provide manually controlled means to switch from the primary to the secondary source. However, the user sometimes is unable to manually switch to his auxiliary source, and may not even be aware that his main source is depleted or that the flow therefrom is interrupted. A pilot, for example, may be unconscious or injured and unable to manually switch from the main oxygen source carried in his aircraft to the portable auxiliary source carried on his person upon ejection from the craft. Automatic actuators have been proposed, but so far as I am aware they are not directly responsive only to actual demand of the user for more oxygen. A primary object of my invention is to provide an oxygen supply system having a primary source normally providing oxygen to the user with means automatically establishing communication with an auxiliary source of oxygen in response to an abnormally strong inspiration effort by the user. The natural, involuntary reaction of a pilot or any user of an oxygen system upon interruption, insufficiency or depletion of the oxygen supply is an abnormal, convulsive inspiration effort in the form. of a gasp.
'lhe actuating means of this invention distinguish between such an abnormal inspiration effort and normal breathing efforts and are operable only in response to the former. The auxiliary source therefore is turned on only upon actual need by the user.
In certain instances, however, it is unnecessary and undesirable to automatically establish communication between the face mask and an auxiliary source of oxygen upon interruption or depletion of the main source. Environmental conditions may make the establishment and 3,456,642 Patented July 22, 1969 consequent depletion of such secondary source unnecessary as, for example, when a pilot ejects from his aircraft at an altitude sufficiently low as not to require supple mental oxygen or when testing the apparatus at ground level.
Accordingly, it is another object of my invention to provide an actuator having the foregoing characteristics and which is operable only in predetermined environmental conditions.
A further object of my invention is to provide an actuator having the foregoing characteristics and which can be manually actuated and reset for testing purposes.
In one aspect thereof, the present invention is characterized by the provision, in combination with first and second fluid supply means, a face mask, and means including a conduit normally providing breathing fluid to the wearer of the face mask from the first supply, of pressure sensitive means communicating with said conduit and operable responsive to an abnormal inspiration effort to establish communication between the second supply and the face mask.
Various other novel features of construction and advantages inherent in the actuator construction of the present invention are pointed out in the following detailed description of an illustrative embodiment thereof considered in conjunction with the accompanying drawings depicting the same wherein like numerals represent like parts throughout the various views.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS FIG. 1 is a perspective view of a pilot shown using a multi-source oxygen system with portions of his ejection seat and survival equipment cut away to illustrate the actuator of the present invention and an auxiliary oxygen source;
FIG. 2. is a fragmentary cross sectional view of the actuator of the present invention taken about on line 22 of FIG. 3;
FIG. 3 is a fragmentary cross sectional view thereof taken about on line 3-3 of FIG. 1;
FIG. 4 is a fragmentary cross sectional view of a handle used in the actuator thereof;
FIG. 5 is a fragmentary cross sectional view of the actuator of the present invention taken about on line 55 of FIG. 3; and
FIG. 6 is a fragmentary view thereof taken about on line 6-6 of FIG. 3.
DETAILED DESCRIPTION Referring now to the accompanying drawings, FIG. 1 shows a pilot wearing a face mask 10 supplied with oxygen from a main oxygen supply source fixed in the aircraft (both of which are well known in the art and therefore not shown) through conduits including a main hose 11 and a feeder hose 12. In the illustrated form, the pilot carries a secondary or auxiliary oxygen source comprising a tank 13 secured in parachute pack 14 and having a connecting conduit 15 communicating with feeder hose 12 through a Y connector 16 which includes a check valve (not shown) to prevent the escape of oxygen from reserve tank 13 through main hose 11. Tank 13 can be a conventional bottle or cylinder of oxygen under relatively high pressure.
A seat member 32 threads into the enlarged bore portion 30 and comprises an axial port 33, a plurality of circumferentially spaced openings 34 therearound communicating between opposite sides of seat member 32 and a cylindrical recess 35 opening through the face thereof away from tank 13. A flow controller 36, of known construction, is disposed in bore 23 and oxygen flows from tank 13 through passage 24 and through controller 36, port 33 (when open) and into recess 35.
Under normal conditions, port 33 is sealed by a poppet valve 37 which is axially slidable in a retainer 38 threaded in a further enlarged extension of bore 23 to abut and seat against port 33 within recess 35. A tension spring 39 engages the base of recess 35 and a radial flange 40 on valve 37 and biases valve 37 to an open position. A diaphragm 41, secured behind flange 40 and peripherally sealed between retainer 38 and a shoulder 42 on housing 20, seals bore 24 from a cavity 43 in housing 20 containing a toggle mechanism generally designated 45.
Toggle operator 58 includes an aneroid 60 positioned in an outwardly opening chamber 61 formed in housing 20. A bellows-type aneroid is illustrated but it will be understood that other types of aneroids and pressure responsive mechanisms may be utilized without departing from the scope of the present invention. A cap screw 62 having circumferentially spaced openings 63 communicating between the ambient atmosphere and chamber 61 threads in the outer end of chamber 61. Aneroid 60 is fixed at one end to the inner face of capscrew 62 and is free to axially flex inwardly in chamber 61. The other end of aneorid 60 carries a plunger 65 having a reduced diameter stem 66 at one end defining a shoulder 67.
Under normal conditions, the oxygen user, a pilot in the illustrated form, will draw oxygen from the fixed primary source of the craft (not shown) through main hose 11 and feeder hose 12 to face mask 10, under control of the usual demand regulator, indicated at 115 and located between connector 16 and the primary source, indicated at 116. The suctive effect of each inspiration effort therefore is communicated to chamber 82, and reduces the pressure therein. However, the increased pressure differential on diaphragm 78 resulting from a normal breathing effort is insufficient to overcome the bias of spring 84, which is selected to resist all but a truly abnormally strong inspiration effort. Therefore, with a normal breathing effort valve 37 remains closed. However, if the pilots primary source 116 fails or is cut off, as for example upon ejection from the aircraft, his natural reaction to the absence of sufficient oxygen during his next inspiration will be to gasp and make an abnormally strong inspiration effort. This will radically lower the pressure in chamber 82 and the resulting pressure differential will be sufficient to move diaphgram 78 inwardly against the bias of spring 84. The end leg 75 follows the inward movement of diaphragm 78 to pivot stop member 72 and swing the end of leg 71 out of interfering relation with stem 66. Aneroid 60 is thereby freed to expand and engage end shoulder 67 of plunger 65 with middle tine 50 of toggle mechanism 45 to carry the same past center, against the bias of spring 47 into engagement against a stop 88, thereby releasing valve 37. Spring 39 urges poppet valve 37 open to permit oxygen in reserve tank 13 to flow through controller 36, port 33, recess 35, openings 34-, passage 29, hose 15 and into face mask 10. However, this will occur only at or above a predetermined altitude, providing sufficient pressure differential on aneroid 60 to produce the foregoing expansion movement thereof.
It is thus apparent that actuator 18 establishes communication between face mask 10 and auxiliary oxygen supply 13 only in response to an abnormal inspiration effort, reflecting an actual demand for oxygen, and then only when the ambient atmospheric pressure is below a predetermined level, as would exist at altitudes above 9,000 feet. If an abnormal inspiration effort is made at a low altitude, not requiring the use of auxiliary oxygen, aneroid 50 would not expand axially sufficiently to engage and move toggle mechanism 45 over center to release the reserve oxygen to face mask 10.
Since actuator 18 is designed not to operate automatically below a predetermined altitude, a manual actuating device and reset generally designated 90 is provided to test the toggle mechanism 45 and the availability of reserve oxygen to face mask 10 upon actuation of toggle mechanism 45. It also provides an emergency release operable independently of the automatic inspiration responsive mechanism in the event of malfunction of the latter.
The other end of probe 94 is suitably anchored in a retaining sleeve 105 (FIG. 4) secured within a handle 106 by retaining rings 107. To manually actuate toggle 45 handle 106 is pulled retracting sleeve 95 against the bias of spring 103 and causing leg 100 of slide 99 to engage behind middle tine 50 and carry toggle 45 over center, thereby releasing valve 37 and opening port 33 to permit oxygen from auxiliary tank 13 to flow to face mask 10. To prevent inadvertent manual actuation of actuator '18 a cotter pin 107 engages through and interlocks adaptor 91 and sleeve 95 to prevent sleeve 95 from sliding in adaptor 95. Pin 107 must be removed prior to manual actuation.
To restore toggle 45 to its previous position, shown in the drawings, and thereby reset the actuator, the outer end of inner probe 93 passes through retaining sleeve 105 in handle 106 and is secured to a reset button 108 carried in a recess 109 in handle 106. Button 108 telescopes in retaining sleeve 105 and is biased outwardly by a spring 110 engaging between the underside of button 108 and the base of recess 109. Plunger 96 at the opposite end of probe 93 engages against a shoulder 111 on sleeve 95 to limit such outward movement of probe 93 and button 108. Depression of button 108 causes plunger 96 to engage middle tine 50 and push toggle 45 back to the normal over center locking position shown in FIG. 3.
Thus, it will be appreciated that the present invention fully accomplishes its intended objects by providing an automatic turn-on for multi-source oxygen systems which reacts instantly to abnormally strong inspiration effort to restore oxygen flow after one source has aborted. By utilizing the inspiration effort of the oxygen user to trigger the actuator, automatic operation, at the instant a lack of oxygen occurs, is insured. While designed primarily for automatic operation at relatively high altitudes, it is readily apparent that the actuator of the present invention can be operated at any desired altitude by changing aneroid 58 to respond to diflerent pressures. Manual actuating device 90 provides a means to test the auxiliary oxygen system and an emergency means for establishing communication between the auxiliary oxygen supply and face mask 10.
While the breathing fluid has been referred to herein as oxygen, it is obvious that the invention is usable with breathing fluids of any mixture. Having thus described and illustrated a preferred form of the actuator construction invention, it will be understood that such description and illustration is by way of example only and that such modifications and changes as may suggest themselves to those skilled in the art are intended to fall within the scope of the present invention which is limited only by the appended claims.
What I claim is:
1. In a breathing fluid supply system, a face mask, conduit means connected to said mask and adapted for connection to a first source of breathing fluid for providing fluid to the wearer of said face mask from such first source during normal inspiration, a second source of breathing fluid, and actuating means including pressure sensitive means communicating with said conduit means operable automatically in response to an abnormally strong inspiration effort by a wearer of said mask to establish communication between said second source and said face mask.
2. A breathing system according to claim 1 together with a valve normally interrupting communication between said mask and said second source, valve control means including a valve operator movable between valve opening and closing positions, and means responsive to a predetermined pressure to move said valve operator to its valve opening position, said pressure sensitive means being operable during normal inspiration to prevent said valve from opening.
3. A breathing system according to claim 2 wherein said valve operator comprises a spring biased toggle, said predetermined pressure reponsive means being operable to engage said toggle and move the same overcenter to open said valve, said pressure sensitive means disabling said predetermined pressure responsive means during normal inspiration to prevent opening of said valve.
4. A breathing system according to claim 2 wherein said predetermined pressure responsive means comprises an aneroid.
5. A breathing system according to claim 2 including manually operable means movable to engage said valve operator and move the latter to said valve opening position, said manual means including valve reset means movable to engage said valve operator and move the latterto said valve closing position.
6. A breathing system according to claim 3, together with coaxial members slidable relative to one another, one of said members being adapted to engage and move said toggle to said valve opening position, the other of said members being adapted to engage and move said toggle to said valve closing position, and manual means operable to slide said members independently of one another.
7. A breathing system according to claim 3 wherein said predetermined pressure responsive means includes a stem movable to engage said toggle, said pressure sensitive means including a chamber closed by a diaphragm and communicating with said face mask, a locking member normally engaging said stem to restrain the same from movement, said locking member being movable to release said stem in response to movement of said diaphragm into said chamber, and means yieldably restraining said diaphragm against such movement.
8. A breathing system according to claim 1 connected to the breathing fluid supply system of a vehicle as the first source, wherein said second source comprises a tank of compressed breathing fluid carried by the wearer of said mask.
References Cited UNITED STATES PATENTS FOREIGN PATENTS 907,390 10/ 1962 Great Britain.
LAWRENCE W. TRAPP, Primary Examiner
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US60497966A | 1966-12-27 | 1966-12-27 |
Publications (1)
Publication Number | Publication Date |
---|---|
US3456642A true US3456642A (en) | 1969-07-22 |
Family
ID=24421790
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US604979A Expired - Lifetime US3456642A (en) | 1966-12-27 | 1966-12-27 | Demand actuating means for alternate breathing supply |
Country Status (1)
Country | Link |
---|---|
US (1) | US3456642A (en) |
Cited By (14)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4274404A (en) * | 1979-04-13 | 1981-06-23 | American Safety Flight Systems, Inc. | Oxygen supply system controlled by user exhalation |
US4404969A (en) * | 1977-11-11 | 1983-09-20 | Cresswell Arnold W | Respirators |
EP0269900A1 (en) * | 1986-11-12 | 1988-06-08 | Enrico Domenico Bozano | Air regulator for breathing apparatus |
US4841953A (en) * | 1986-11-07 | 1989-06-27 | Dodrill Gregg W | Auxiliary supply system for a portable self-contained breathing apparatus |
US5542447A (en) * | 1994-01-18 | 1996-08-06 | Normalair-Garrett (Holdings) Limited | Aircrew breathing systems |
US5645055A (en) * | 1992-08-12 | 1997-07-08 | Conax Florida Corporation | Oxygen breathing controller |
US5730121A (en) * | 1996-07-19 | 1998-03-24 | Hawkins, Jr.; Albert D. | Emergency air system |
FR2768633A1 (en) * | 1997-09-24 | 1999-03-26 | Draeger Aerospace Gmbh | Mobile breathing gas supply unit for use in planes |
US20020144679A1 (en) * | 2001-04-04 | 2002-10-10 | Jean-Michel Cazenave | Process and installation for the distribution of air enriched in oxygen to passengers of an aircraft |
US20040182394A1 (en) * | 2003-03-21 | 2004-09-23 | Alvey Jeffrey Arthur | Powered air purifying respirator system and self contained breathing apparatus |
US6837243B1 (en) | 2003-09-30 | 2005-01-04 | Scott Technologies, Inc. | Automatic transfer regulator for hose-line respirator |
US20060048777A1 (en) * | 2003-03-21 | 2006-03-09 | Interspiro, Inc. | Apparatus and method for providing breathable air and bodily protection in a contaminated environment |
US20070235030A1 (en) * | 2003-08-22 | 2007-10-11 | Teetzel James W | Self-contained breathing system |
SE1950911A1 (en) * | 2019-08-02 | 2021-01-12 | Interspiro Ab | Arrangement for breathing apparatus, and breathing apparatus |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2329289A (en) * | 1940-09-14 | 1943-09-14 | Silas A Morehouse | Oxygen supply for parachutists |
US2824557A (en) * | 1956-08-23 | 1958-02-25 | Aerotec Corp | Control apparatus for the air and oxygen supply in the suits of aircraft personnel |
GB907390A (en) * | 1960-03-15 | 1962-10-03 | Firewel Company Inc | Differential gas supplying apparatus |
-
1966
- 1966-12-27 US US604979A patent/US3456642A/en not_active Expired - Lifetime
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2329289A (en) * | 1940-09-14 | 1943-09-14 | Silas A Morehouse | Oxygen supply for parachutists |
US2824557A (en) * | 1956-08-23 | 1958-02-25 | Aerotec Corp | Control apparatus for the air and oxygen supply in the suits of aircraft personnel |
GB907390A (en) * | 1960-03-15 | 1962-10-03 | Firewel Company Inc | Differential gas supplying apparatus |
Cited By (28)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4404969A (en) * | 1977-11-11 | 1983-09-20 | Cresswell Arnold W | Respirators |
US4274404A (en) * | 1979-04-13 | 1981-06-23 | American Safety Flight Systems, Inc. | Oxygen supply system controlled by user exhalation |
US4841953A (en) * | 1986-11-07 | 1989-06-27 | Dodrill Gregg W | Auxiliary supply system for a portable self-contained breathing apparatus |
EP0269900A1 (en) * | 1986-11-12 | 1988-06-08 | Enrico Domenico Bozano | Air regulator for breathing apparatus |
US5645055A (en) * | 1992-08-12 | 1997-07-08 | Conax Florida Corporation | Oxygen breathing controller |
US5542447A (en) * | 1994-01-18 | 1996-08-06 | Normalair-Garrett (Holdings) Limited | Aircrew breathing systems |
US5730121A (en) * | 1996-07-19 | 1998-03-24 | Hawkins, Jr.; Albert D. | Emergency air system |
FR2768633A1 (en) * | 1997-09-24 | 1999-03-26 | Draeger Aerospace Gmbh | Mobile breathing gas supply unit for use in planes |
US20020144679A1 (en) * | 2001-04-04 | 2002-10-10 | Jean-Michel Cazenave | Process and installation for the distribution of air enriched in oxygen to passengers of an aircraft |
US6701923B2 (en) * | 2001-04-04 | 2004-03-09 | L'air Liquide - Societe Anonyme A Directoire Et Conseil De Surveillance Pour L'etude Et L'exploitation Des Procedes Georges Claude | Process and installation for the distribution of air enriched in oxygen to passengers of an aircraft |
US20040099271A1 (en) * | 2001-04-04 | 2004-05-27 | L' Air Liquide, Societe Anonyme A Directoire Et Conseil De Surveillance Pour L'etude | Process and installation for the distribution of air enriched in oxygen to passengers of an aircraft |
US6948498B2 (en) | 2001-04-04 | 2005-09-27 | L'Air Liquide-Societe Anonyme a Diretoire et Conseil de Surveillance pour l'Etude et l'Exploitation des Procedes Georges Claude | Process and installation for the distribution of air enriched in oxygen to passengers of an aircraft |
US20050022817A1 (en) * | 2003-03-21 | 2005-02-03 | Tvi Corporation | Breathing apparatus |
US7380551B2 (en) * | 2003-03-21 | 2008-06-03 | Tvi Corporation | Breathing apparatus |
US20040182395A1 (en) * | 2003-03-21 | 2004-09-23 | Brookman Michael J. | Powered air purifying respirator system and breathing apparatus |
US20040182394A1 (en) * | 2003-03-21 | 2004-09-23 | Alvey Jeffrey Arthur | Powered air purifying respirator system and self contained breathing apparatus |
US20060048777A1 (en) * | 2003-03-21 | 2006-03-09 | Interspiro, Inc. | Apparatus and method for providing breathable air and bodily protection in a contaminated environment |
US20060191533A1 (en) * | 2003-03-21 | 2006-08-31 | Interspiro, Inc. | Powered air purifying respirator system and breathing apparatus |
US7543584B2 (en) * | 2003-03-21 | 2009-06-09 | Interspiro, Inc. | Powered air purifying respirator system and breathing apparatus |
US20070235030A1 (en) * | 2003-08-22 | 2007-10-11 | Teetzel James W | Self-contained breathing system |
US7647927B2 (en) | 2003-08-22 | 2010-01-19 | Wilcox Industries Corp. | Self-contained breathing system |
US20100224193A1 (en) * | 2003-08-22 | 2010-09-09 | Wilcox Industries Corp. | Self-contained breathing system |
US8113198B2 (en) | 2003-08-22 | 2012-02-14 | Wilcox Industries Corp. | Self-contained breathing system |
US8950401B2 (en) | 2003-08-22 | 2015-02-10 | Wilcox Industries Corp. | Self-contained breathing system |
US10130831B2 (en) | 2003-08-22 | 2018-11-20 | Patriot Life Support, Inc. | Self-contained breathing system |
US6837243B1 (en) | 2003-09-30 | 2005-01-04 | Scott Technologies, Inc. | Automatic transfer regulator for hose-line respirator |
SE1950911A1 (en) * | 2019-08-02 | 2021-01-12 | Interspiro Ab | Arrangement for breathing apparatus, and breathing apparatus |
SE543420C2 (en) * | 2019-08-02 | 2021-01-12 | Interspiro Ab | Arrangement for breathing apparatus, and breathing apparatus |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US3456642A (en) | Demand actuating means for alternate breathing supply | |
US4173986A (en) | Pressurized gas flow control valve and assembly thereof with reducer regulator | |
US3875957A (en) | Oxygen-air diluter device | |
US4693242A (en) | Coupling connectors for respirator masks | |
US3608574A (en) | Diaphragm-valve especially for a respiratory-gas supply system | |
US3444857A (en) | Compensated action nonreturn exhalation valve,more particularly for respiratory mask | |
US5275153A (en) | Demand valve having reaction load means and an insertable trigger element | |
EP0050052B1 (en) | Automatic diluter/demand oxygen regulator adapted for use in a toxic environment | |
US2703572A (en) | Mask and pressure suit combination oxygen regulator | |
AU749421B2 (en) | Standby regulator for breathing system | |
US3768466A (en) | Automatic oxygen breathing apparatus | |
US3179119A (en) | Breathing apparatus | |
US2597039A (en) | Pressure breathing demand oxygen regulator | |
US4850345A (en) | Pilot operated valves | |
US3091365A (en) | Pressure releasing means | |
US4127129A (en) | Oxygen regulator | |
US2963034A (en) | Aneroid valve for maintaining a minimum pressure | |
US2697538A (en) | Aneroid actuated pressure release device | |
US2892456A (en) | Pressure demand breathing oxygen mask with built-in regulator | |
US3045691A (en) | Aircraft breathing systems | |
US3106203A (en) | Anti-blackout valve | |
US5542447A (en) | Aircrew breathing systems | |
US2627866A (en) | Demand regulator | |
GB1106766A (en) | Fluid flow regulators | |
US2969801A (en) | Regulator |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AS | Assignment |
Owner name: FIGGIE INTERNATIONAL INC. Free format text: CHANGE OF NAME;ASSIGNOR:A-T-O INC.;REEL/FRAME:003866/0442 Effective date: 19810623 |