Control Means Responsive To Variation In Ambient Pressure Patents (Class 128/204.29)
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Publication number: 20100000526Abstract: An oxygen supply device with at least one oxygen source and with a breathing mask connectable to the oxygen source. An intermediate container is provided, to which the oxygen source may be conductively connected.Type: ApplicationFiled: April 20, 2006Publication date: January 7, 2010Inventor: Wolfgang RITTNER
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Patent number: 7621275Abstract: A cover assembly for mask containers with two covers, wherein the covers have a pivot axis parallel to the longitudinal axis of the aircraft and further, are pivotable at 90°.Type: GrantFiled: February 24, 2005Date of Patent: November 24, 2009Assignee: Airbus Deutschland GmbHInventor: Hans Joachim Fischer
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Patent number: 7617825Abstract: A closure device of a second-stage regulator for scuba divers, the regulator comprising a regulator body with an inlet conduit for connection to a first-stage regulator which supplies a breathable gaseous mixture at relatively constant pressure, an outlet conduit for connection to a mouthpiece of the users, and an opening closed by a deformable diaphragm. The device comprises a locking frame connected in an articulated manner or jointedly to the regulator body to lock the diaphragm in the opening, and a member for fastening the frame to the regulator body.Type: GrantFiled: July 26, 2004Date of Patent: November 17, 2009Assignee: Cressi-Sub S.p.A.Inventor: Stefano Pedemonte
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Patent number: 7604019Abstract: The electromechanical regulator for passenger oxygen is a hybrid oxygen regulator that provides for electronic or mechanical regulation of oxygen flow. The electronic portion of the regulator consists of an inlet solenoid valve, an outlet solenoid valve, a cabin pressure transducer, a regulated output transducer and a PID based controller, and the solenoid valves are normally biased so that in the event of an electronic system failure or a power supply failure the system will automatically revert to mechanical operation.Type: GrantFiled: July 20, 2006Date of Patent: October 20, 2009Assignee: B/E Intellectual PropertyInventor: Robert Frederick Frampton
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Patent number: 7588031Abstract: A pressure support system has a motor, a switching element that supplies power to motor windings, and a blower coupled to the motor. Rotation of the blower elevates a pressure of fluid in a patient circuit coupled to an outlet of the blower. A rotational speed controller maintains the motor at a set rotational speed corresponding to a selected pressure for the fluid in the patient circuit. The rotational speed of the motor is maintained by a switching signal provided by a rotational speed controller to the switching element to control the actuation of the switching element. A fluid parameter monitoring portion monitors a parameter associated with the flow of fluid in the patient circuit, such as the magnitude, direction, or volume, based on a characteristic, such as duty cycle, of the switching signal, or based on a characteristic of a control signal that is used to generate the switching signal.Type: GrantFiled: September 23, 2005Date of Patent: September 15, 2009Assignee: Ric Investments, LLCInventors: William A Truschel, Patrick W Truitt, Winslow K Duff
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Publication number: 20090145436Abstract: The invention relates to a breathing apparatus for an aircraft crew member comprising at least one breathing mask (10) provided with a regulator (12) and an inflatable pneumatic harness (14) for rapid donning of said mask, said regulator being connected to a source of breathable gas (30) through a first feedline, said breathing apparatus further comprising a first buffer plenum (134) having an outlet connected to said pneumatic harness for inflating said harness with compressed gas, and compression means (50) for delivering said compressed gas to said first buffer plenum. The invention also relates to a method for filling the first buffer plenum.Type: ApplicationFiled: April 20, 2006Publication date: June 11, 2009Inventor: Severine Aubonnet
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Publication number: 20090126737Abstract: The invention relates to a breathing apparatus for an aircraft crew member, said apparatus comprising at least one breathing mask (620) provided with a demand regulator (810), said demand regulator being linked through a feedline to a central source of oxygen enriched air (600), so that oxygen enriched air is supplied to said breathing mask, and pressure regulating means (601,602,603, 604) provided on said feedline between said central source and said demand regulator and adapted, to level the pressure fluctuations of said oxygen enriched air supplied to said breathing mask.Type: ApplicationFiled: November 9, 2005Publication date: May 21, 2009Inventors: Severine Aubonnet, Andrew R.T Tatarek-Gintowt
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Publication number: 20090101149Abstract: The invention relates to a breathing apparatus for providing a respiratory gas to a crewmember in a cabin of an aircraft, said breathable apparatus comprising an air inlet (5) for admission of ambient air in said breathing apparatus, an additional gas inlet (2) for admission of additional gas in said breathing apparatus, an outlet nozzle (4) for feeding said crew member with the respiratory gas comprising said ambient air and/or additional gas, said breathing apparatus further comprising neutralizing means (70, 141) for neutralizing at least partially the admission of said additional gas below a predefined cabin altitude (Z1).Type: ApplicationFiled: April 20, 2006Publication date: April 23, 2009Inventors: Leopoldine Bachelard, Vincent Gillotin
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Patent number: 7500481Abstract: An apparatus (1) to assist a patient's respiration by delivering air to a patient through a mask (20), including a ramp module (10) connected to a control unit (2) to provide the control unit with a pressure value PM at mask (20), so that when apparatus (1) starts functioning, the pressure progressively rises until it reaches a treatment pressure PTi, the apparatus further including a comparator connected to ramp module (10), at least one device for detecting the patient's breathing parameters and sending them to the comparator, so that the comparator can determine whether an event (E1, E2 or E3) occurs in patient's breathing and to send the corresponding data to ramp module (10) which provides control unit (2) with a pressure value PM that will speed up with respect of time, so that the pressure rise at patient's mask (20) is accelerated.Type: GrantFiled: March 10, 2003Date of Patent: March 10, 2009Assignee: Kaerys S.A.Inventors: Alain Delache, Véronique Delache
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Patent number: 7497216Abstract: The claim over prior art is for an approach to an electronically controlled or electronically monitored breathing system that represents an improvement in electrical reliability, manufacturing cost and efficiency, user maintenance, system reliability, user cost and maintenance. These improvements are accomplished by placing the major electronic, mechanical and electromechanical control elements and sensor components in a single replaceable module.Type: GrantFiled: August 30, 2005Date of Patent: March 3, 2009Inventors: David E. Forsyth, Wayne K. Miller
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Publication number: 20080283060Abstract: A ventilator that delivers air at different pressures to a patient during inspiratory and expiratory cycles of breathing and that cycles from inspiratory to expiratory operation when the patient's respiratory flow passes a threshold level. The threshold generally increases from the beginning of inspiration to the end of inspiration. The increase can be linear over all or only a portion of the inspiratory cycle, and the threshold can be adjusted so that cycling is prevented during the initial portion of an inspiratory cycle. The minimum and maximum levels may both be functions of peak flow and the threshold may increase as a function of elapsed inspiratory time. The rate at which the threshold increases from a minimum level to a maximum level may be adjustable for individual patient needs and may be determined from previous breaths.Type: ApplicationFiled: June 22, 2005Publication date: November 20, 2008Inventor: David John Bassin
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Publication number: 20080078393Abstract: A cannula receives respiratory airflows and ambient airflows; a differential pressure transducer determine pressure differentials between the respiratory airflows and the ambient airflows; and a ventilator responds to the pressure differentials. Another receives respiratory airflows and interface airflows; a differential pressure transducer determine pressure differentials between the respiratory airflows and the interface airflows; and a ventilator responds to the pressure differentials. And another receives respiratory airflows from a subject and interface airflows from an area near a cannula; a differential pressure transducer determine pressure differentials between the respiratory airflows and the interface airflows; and a ventilator responds to the pressure differentials. Corresponding respiratory monitoring methods receive, determine, and control the same.Type: ApplicationFiled: December 20, 2006Publication date: April 3, 2008Applicant: GENERAL ELECTRIC COMPANYInventors: Jaron Matthew Acker, Robert Quin-Yew Tham, Kristopher John Bilek, Andrew Phillip Levi, Steven James Zambon
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Patent number: 7343918Abstract: A breathing gas feed assembly for the flight crew of an airplane comprises an emergency breathing mask and a stowage box for the mask. The box is adapted to receive the mask diagonally and it is closed by two doors hinged about respective hinge axes situated on two adjacent edges of the box.Type: GrantFiled: November 18, 2003Date of Patent: March 18, 2008Assignee: IntertechniqueInventors: Patrice Martinez, Philippe Gerard, Benoit Lelievre, Dominique Lemasson
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Publication number: 20080041376Abstract: A safety system and method of an air distribution system of a mine structure is disclosed. In one embodiment, the air distribution includes a supply unit installed on a particular wall of the first set of walls to facilitate delivery of breathable air from a source of compressed air to an emergency support system of the mine structure, a fill site interior to the mine structure to provide the breathable air to a breathable air apparatus at multiple locations of the mine structure, a secure chamber of the fill site as a safety shield that confines a possible rupture of an over-pressurized breathable air apparatus within the secure chamber, a distribution structure that is compatible with use with compressed air that facilitates dissemination of the breathable air of the source of compressed air to multiple locations of the mine structure.Type: ApplicationFiled: August 16, 2006Publication date: February 21, 2008Inventor: Anthony J. Turiello
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Patent number: 7331345Abstract: A self contained breathing apparatus (SCBA) served by a source of breathing gas with a mask and a demand regulator connected to the mask. The regulator has a flexible diaphragmatic member having a side exposed to pressure differentials to cause a valve mechanism to introduce breathing gas to the mask. An expanding and contracting member and a chamber fluidically connected to the diaphragm compensates for movement of the diaphragm while shielding the diaphragm from ambient contaminants.Type: GrantFiled: January 30, 2003Date of Patent: February 19, 2008Assignee: Survivair Respirators, LLCInventor: David V. Haston
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Patent number: 7246620Abstract: A noninvasive system for monitoring the oxygen saturation level of a person subjected to reduced atmospheric pressure for avoiding hypoxemia. The system monitors a person's oxygen saturation level, comparing the saturation level to a predetermined level. When the measured saturation level is less than the predetermined level, the person is then supplied with an oxygen mixture for increasing the subject's oxygen saturation level to a safe level. The person's exposed reduced atmospheric pressure is also compared with a predetermined range of pressure levels. If this predetermined range of pressure levels is exceeded or maintained for a predetermined time duration, the person is then supplied with an oxygen mixture. Additionally, a device is provided for performing oxygen flight planning calculations for estimating oxygen usage for a predetermined flight plan that is based on the above system.Type: GrantFiled: October 30, 2003Date of Patent: July 24, 2007Inventor: John D. Conroy, Jr.
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Patent number: 7165546Abstract: A self-contained system which converts nitrous oxide to a breathable gas mixture of nitrogen and oxygen. In the preferred embodiment of the present invention, a portable system is disclosed wherein liquefied nitrous oxide is converted to a breathable gas mixture of nitrogen and oxygen. The decomposition occurs over a catalyst bed which is all contained in a small reactor. The invention is useful for underwater, fire fighting and outer space applications.Type: GrantFiled: May 25, 2001Date of Patent: January 23, 2007Assignee: Pioneer AstronauticsInventors: Brian M. Frankie, Robert M. Zubrin, Scott E. Lowther
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Patent number: 7089940Abstract: A valve device, particularly for a breathing regulator for divers, including an inlet chamber which can be connected to a source of gas under super-atmospheric pressure, and an outlet chamber which is under a regulated pressure. A seating, which is movable under the influence of the super-atmospheric pressure and the regulated pressure, seals between the inlet chamber and the outlet chamber and has a through-passing passageway that interconnects the chambers. Also included is a valve body which is movably arranged in the seating such as to open and close the through-passing passageway in the seating. A servo element exerts on the valve body a force that depends on the position of the movable seating, so that varying force-influence on the valve body from the super-atmospheric pressure will be compensated for by a corresponding varying force from the servo element. This results in an essentially constant valve characteristic, while providing a mechanically simple solution at the same time.Type: GrantFiled: October 11, 2002Date of Patent: August 15, 2006Assignee: Poseidon Industri ABInventor: Anders Kellstr{hacek over (o)}m
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Patent number: 7082944Abstract: A dual air supply breathing apparatus that allows a user to quickly and easily switch between two or more sources of air or compressed gas, such as filtered air from a Powered Air Purifying Respirator (PAPR) and compressed air from a Self-Contained Breathing Apparatus (SCBA). In one variation, the dual air supply breathing apparatus uses a Y-shaped changeover valve with two input tubes and one output tube. The first input tube receives filtered air from a PAPR and the second input tube receives compressed air from a tank. An actuator controls a flap valve within the changeover valve to seal off one of the input tubes while creating a flow path between the other input tube and the output tube. The changeover valve may be controlled by manipulating the high-pressure valve on the tank of compressed gas and/or by manipulating the switch that activates the PAPR.Type: GrantFiled: September 10, 2003Date of Patent: August 1, 2006Assignee: TVI CorporationInventor: Otto Gossweiler
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Patent number: 6955710Abstract: Method and system on board an aircraft for the production of an oxygen-enriched gas stream from an oxygen/nitrogen gas mixture, particularly air, comprising at least one adsorber containing at least one adsorbent for adsorbing at least some of the nitrogen molecules contained in the oxygen/nitrogen feed mixture, characterized in that the adsorbent comprises a faujasite-type zeolite, having a Si/Al ratio of 1 to 1.50, exchanged to at least 80% with lithium cations. Aircraft equipped with such a system, in particular an airliner, especially an airliner of the long-range, large-capacity type.Type: GrantFiled: May 1, 2003Date of Patent: October 18, 2005Assignee: L'Air Liquide, Societe Anonyme pour l'Etude et, l 'Exploitation des Procedes Georges ClaudeInventors: Stéphane Lessi, Richard Zapata, Jean-Michel Cazenave, Jean Dehayes
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Process and installation for the distribution of air enriched in oxygen to passengers of an aircraft
Patent number: 6948498Abstract: According to this process, there is supplied to the passengers a first fraction of air enriched in oxygen from independent supply elements, in particular high pressure cylinders (16), during a descent phase of the aircraft between a normal cruising altitude and an intermediate re-routing altitude. There is moreover compressed air taken from a source of compressed air belonging to the aircraft, to produce (in 2) a second fraction of the air enriched in oxygen which is delivered to the passengers, at least during a phase of stabilized flight of the aircraft, adjacent the re-routing altitude, greater than 5,500 meters.Type: GrantFiled: November 6, 2003Date of Patent: September 27, 2005Assignee: L'Air Liquide-Societe Anonyme a Diretoire et Conseil de Surveillance pour l'Etude et l'Exploitation des Procedes Georges ClaudeInventors: Jean-Michel Cazenave, Jean Dehayes, Olivier Vandroux, Richard Zapata -
Patent number: 6929006Abstract: A respirator with a tidal volume-measuring device (6) between a respiration bag (8) and a patient adapter (2) provides accurate metering of the tidal volume. The device includes a first pressure-measuring device (4) and a breathing gas interruptor (5) in series sequence between the patient adapter (2) and the tidal volume-measuring device (6). A second pressure-measuring device (7) is provided between the tidal volume-measuring device (6) and the respiration bag (8). A control unit (20) is connected with the tidal volume-measuring device (6) and the pressure-measuring devices (4, 7) and sends control signals in such a way that when a predetermined tidal volume is reached, the breathing gas interrupter (5) is switched to the closed position, and that the closed position is eliminated when the pressure p2 measured with the second pressure-measuring means (7) has dropped below the pressure p1 determined with the first pressure-measuring means (4).Type: GrantFiled: November 8, 2004Date of Patent: August 16, 2005Assignee: Dräger Medical AG & Co. KGaAInventors: Thomas Krüger, Hans-Georg Wahle
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Patent number: 6913016Abstract: A valve manifold assembly having a valve body with at least one chamber defined therein. The chamber has at least one inlet and at least one outlet and has at least one opening. A poppet is disposed in the chamber. The poppet slides in the chamber between a first position where the poppet seals the inlet and a second position where the poppet is disposed in spaced-apart relation relative to the inlet. The poppet has an opening disposed therein. A pin having a first section with a first diameter and having a second section with a second diameter is capable of being slidably disposed through the at least one opening in the valve body and through the opening in the poppet.Type: GrantFiled: January 6, 2003Date of Patent: July 5, 2005Assignee: AVOX Systems, Inc.Inventor: Dennis P. Pietrantoni
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Patent number: 6871645Abstract: The present invention includes a non-rebreathing circuit coupled with computer-controlled gas adjustments. Ambient air is diluted with nitrogen on a breath-by-breath basis to provide precise control over the inspired concentration of oxygen/nitrogen mixture, thereby simulating selected altitudes on an almost instantaneous basis. Carbon dioxide and water vapor exhaled by the subject are released into the environment and absorption is not necessary. In addition, the mixed gas can be administered through a standard aviator's oxygen mask, increasing the realism of the simulation and removing obvious external cues on the nature of the experiment. Maintenance on the mixing loop is low when compared to re-breathing units, since no consumable items are necessary to absorb water vapor or carbon dioxide. A mixing device provides a homogenized mixture of nitrogen/oxygen fluid to the subject.Type: GrantFiled: September 16, 2002Date of Patent: March 29, 2005Assignee: The United States of America as represented by the Secretary of the NavyInventors: Richard Wartman, Michael Stiney, Eric Bower, Paul Gardetto, Charles Vacchiano, Kenneth Sausen
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Publication number: 20040144384Abstract: A breathing gas feed assembly for the flight crew of an airplane comprises an emergency breathing mask and a stowage box for the mask. The box is adapted to receive the mask diagonally and it is closed by two doors hinged about respective hinge axes situated on two adjacent edges of the box.Type: ApplicationFiled: November 18, 2003Publication date: July 29, 2004Inventors: Patrice Martinez, Philippe Gerard, Benoit Lelievre, Dominique Lemasson
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Process and installation for the distribution of air enriched in oxygen to passengers of an aircraft
Patent number: 6701923Abstract: According to this process, there is supplied to the passengers a first fraction of air enriched in oxygen from independent supply elements, in particular high pressure cylinders (16), during a descent phase of the aircraft between a normal cruising altitude and an intermediate rerouting altitude. There is moreover compressed air taken from a source of compressed air belonging to the aircraft, to produce (in 2) a second fraction of the air enriched in oxygen which is delivered to the passengers, at least during a phase of stabilized flight of the aircraft, adjacent the re-routing altitude, greater than 5,500 meters.Type: GrantFiled: February 11, 2002Date of Patent: March 9, 2004Assignee: L'Air Liquide - Societe Anonyme a Directoire et Conseil de Surveillance pour l'Etude et l'Exploitation des Procedes Georges ClaudeInventors: Jean-Michel Cazenave, Jean Dehayes, Olivier Vandroux, Richard Zapata -
Patent number: 6688308Abstract: A system and method of performance testing an aircraft's oxygen supply system where demand is assured by in use performance testing and monitoring by a controller and monitor for the partial pressure of oxygen necessary to meet demand in a pressurized aircraft. The system and method utilizing a predetermined performance test signal sent out at pre-programmed intervals of time during use, receiving, evaluation and responding to performance test signal control data received in response to the performance test signal and adjusting the partial pressure of oxygen to meet demand if necessary.Type: GrantFiled: August 20, 1999Date of Patent: February 10, 2004Assignee: Normalair-Garrett (Holdings) LimitedInventors: Robert John Phillips, Christopher Michael Noonan
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Patent number: 6612307Abstract: An oxygen conserver having sensing and delivery ports simultaneously connected with a patient by a dual cannula. Inhalation by a patient produces a partial vacuum to move a sensing diaphragm to a venting position and cause a delivery diaphragm to move to an open position for supplying oxygen to the patient through the delivery port. A manually operable control valve enables continuous oxygen flow through the delivery port independently of operation of the sensing diaphragm.Type: GrantFiled: August 17, 2001Date of Patent: September 2, 2003Assignee: Western/Scott Fetzer CompanyInventor: Douglas S. Byrd
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Publication number: 20030131850Abstract: A valve manifold assembly having a valve body with at least one chamber defined therein. The chamber has at least one inlet and at least one outlet and has at least one opening. A poppet is disposed in the chamber. The poppet slides in the chamber between a first position where the poppet seals the inlet and a second position where the poppet is disposed in spaced-apart relation relative to the inlet. The poppet has an opening disposed therein. A pin having a first section with a first diameter and having a second section with a second diameter is capable of being slidably disposed through the at least one opening in the valve body and through the opening in the poppet.Type: ApplicationFiled: January 6, 2003Publication date: July 17, 2003Inventor: Dennis P. Pietrantoni
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Patent number: 6425394Abstract: A passenger oxygen mask assembly (93) is provided which is adapted to be supported on an existing mask-supporting fixture (16). The assembly (93) includes a hanger (30, 64) having a fixture attachment portion (32, 66) and a mask-retaining portion (34, 68), as well as a conventional oxygen mask (92). The attachment portion (32, 66) has a lower leg (36, 70) presenting a recess (42, 76) adapted to receive the mounting post (18) of a fixture (16), as well as upstanding support arms (50-56, 78, 80). The mask-retaining portion (34, 68) includes segments (58, 60, 88) supported by the arms (50-56, 78, 80). When the hanger (30, 64) is mounted on a fixture (16), a mask (92) may be inserted into the hanger (30, 64) and is releasably retained thereby.Type: GrantFiled: October 10, 2000Date of Patent: July 30, 2002Assignee: BE Intellectual Property Inc.Inventors: Sara G. Weinstein, Gary R. Hannah
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Publication number: 20020074000Abstract: A personal pure air device where an air quality visualizer that can fit in a pocket like a pen samples ambient air quality for VOC's, poisonous gases, ozone, and possibly bacterial or viral content. The invention can contain a personal air bottle containing pure compressed air which can be dispensed through a regulator and tube to a nozzle to provide a plume of pure are around the user's nose and mouth providing a space of purified personal breathing air. The visualizer can be directly connected to the regulator to automatically start a flow of pure air when ambient air quality deteriorates, or the user can simply read the air visualizer and manually start the flow of pure air when desired through the use of valves.Type: ApplicationFiled: November 5, 2001Publication date: June 20, 2002Inventor: George Benda
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Patent number: 6401714Abstract: A self contained breathing apparatus includes a pressure vessel which holds a supply of breathing air. The pressure vessel is in fluid communication through a first stage pressure regulator with a second stage breathing regulator. The breathing regulator is operatively connected to a user face mask. When the pressure available in the supply is at a suitable pressure, the pressure regulator provides pressure to breathing regulator at a first pressure. When the pressure in the supply falls to a value indicative of impending depletion of the air supply, a transfer piston in a step up vale shifts. A change in condition of the step up valve causes a step up piston to increase the output pressure from regulator. This increased pressure moves a sensing piston and causes indicating devices in an alarm circuit to be activated. In alternative embodiments, an electronic alarm module may be used.Type: GrantFiled: April 7, 1999Date of Patent: June 11, 2002Assignee: Scott Technologies, Inc.Inventor: Eugene Giorgini
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Patent number: 6347627Abstract: A self-contained system which converts nitrous oxide to a breathable gas mixture of nitrogen and oxygen. In the preferred embodiment of the present invention, a portable system is disclosed wherein liquefied nitrous oxide is converted to a breathable gas mixture of nitrogen and oxygen. The decomposition occurs over a catalyst bed which is all contained in a small reactor. The invention is useful for underwater, fire fighting and outer space applications.Type: GrantFiled: April 23, 1998Date of Patent: February 19, 2002Assignee: Pioneer Inventions, Inc.Inventors: Brian M. Frankie, Robert M. Zubrin, Scott E. Lowther
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Patent number: 6318364Abstract: A modular, dropout passenger oxygen mask container (10) is provided which allows the container (10) to be used in a variety of different aircraft mask deployment areas presenting respective openings (20) without container modification. The container (10) includes a box (14) having an openable lid (16) and a universal series of component mounts (36-54) in the walls thereof which allow attachment of physically separate oxygen inlet, lid latch and mask oxygen valve components (72,74,76) at multiple locations within the box (14). The components (72,74,76). A separate cover (18) is attached to the lid (16) and is designed to mate with a specific opening (20); preferably, the cover (18) is affixed to lid (16) by means of Velcro (68,70).Type: GrantFiled: July 5, 1999Date of Patent: November 20, 2001Assignee: Be Intellectual Property, Inc.Inventors: Michael D. Ford, Gary Hannah, Sebastien A. Ramus, Sara G. Weinstein
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Patent number: 6302106Abstract: A method and apparatus for a self contained underwater breathing apparatus in which a breathing gas is supplied to a flow loop from two separate gas sources each having a different oxygen fraction, and each controlled by separate mass flow controllers having variable flow rate. The mass controller flow rates are adaptively adjustable to deliver gas at variable flow rates which depend solely on a function of depth. An algorithm determines these specific flow rates from each of the tanks at particular depths, such that the gas flow from an oxygen rich gas source decreases as a function of depth, while the gas flow from a diluent gas source increases as a function of depth, so as to maintain the oxygen partial pressure in the flow loop within a specific pre-determined range.Type: GrantFiled: December 29, 1998Date of Patent: October 16, 2001Inventor: John E. Lewis