Abstract: A demand regulator with air dilution for regulating the pressure and flow of a respiratory gas comprises an inlet for additional gas and an outlet leading to a respiratory mask, and also dilution means. Control means switch a supply of pressurized additional gas between at least two passages. At least one of these passages corresponds to an economy flow and has a restricted cross section for limiting the flow of additional gas transmitted to the inlet. The other passage has a cross section which is such that the additional gas has a maximum flow in order to supply the user with additional gas in a physiologically sufficient manner.

Abstract: In a method of regulating the flow rate of additional oxygen taken from a pressurized inlet for oxygen from a source and admitted into a breathing mask provided with an inlet for dilution ambient air, the ambient pressure and the instantaneous inhaled breathe-in flow rate in terms of volume reduced to ambient conditions are measured in real time. The minimum oxygen content in the complete inhalation phase in order to comply with respiratory standards is computed from the ambient pressure and the instantaneous flow rate of additional oxygen is controlled in such a manner as to satisfy the requirements of the applicable standards with a safety margin that is generally a few percent. There is also described a regulator implementing the above method.

Abstract: 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.

Abstract: Patients may operate a CPAP system to deliver appropriate airway pressure at their home. A patient's apnea problem ca be diagnosed at home without supervision with a CPAP device which delivers a continuously minimum appropriate pressure for substantially the entire period of therapy.

Abstract: A device for reducing dead space in a ventilator system has a first tube connectable to the dead space in the ventilator system for producing a flow path for the transport of gas from dead space in the ventilator system, a suction device connected to the first tube for generating an adjustable negative pressure in the first tube, a second tube connectable to dead space in the ventilator system, for producing a flow path for the transport of gas to dead space in the ventilator system, a pump connected to the second tube for generating an adjustable positive pressure in the second tube, and a control unit which regulates the suction device and the pump. The suction device and the pump are formed by a first chamber and a second chamber, respectively, in an enclosure, separated by a gas-tight, moving partition. The control unit regulates the moving partition to regulate the suction device and the pump for achieving simpler and more reliable operation.

Abstract: A pneumatic oxygen conserving device includes a reservoir of pressurized gas delivered upon inhalation through a single-lumen cannula. Gas flow is interrupted by a series of interconnected passages and chambers, including a check valve which is acted upon by the flow of gas being delivered through the delivery outlet of the device. The device is self regulating to the extent that oxygen pulses of appropriate volume are delivered irrespective of the breathing rate of the user. The device includes a plate with various passages and chambers defined therein in such a way as to reduce the overall length of the device.

Abstract: A system (A) for providing single continuous dose of a gaseous heliox mixture to a patient with breathing difficulty includes a device (1) providing a constant and continuous flow of the heliox mixture, and a gas storage tank (2) for the mixture. A flow control is selectively operated to initiate flow of the heliox to the patient. It has a locking mechanism to prevent it from being turned off after the flow begins. The regulator can be reset for reuse by a service entity.

Abstract: A pressure regulator suitable for use as a breathing demand valve in self-contained breathing equipment comprising a first chamber incorporating an inlet port having an inlet valve therein, preferably in the form of a poppet valve and biased so as to seal of the inlet port, and separated from a second chamber by a diaphragm. The diaphragm co-operates with the end of a stem extending from the poppet valve member of the inlet valve such that, upon inhalation by the user, the diaphragm is deflected towards the inlet valve and exerts a force on the poppet valve stem sufficient to open the poppet valve and, upon exhalation by the user, the diaphragm is deflected away form the inlet valve so that the diaphragm no longer contacts the end of the poppet valve stem and the inlet valve closes.

Abstract: A tubular housing 13 constituting an air supply mechanism for a regulator 1 for diving is provided with a deflector 21 adapted to cover air outlet ports 24, 26 of the housing 13 from immediately above as viewed in a radial direction of the housing 13.

Abstract: A regulator 1 for diving has a tubular housing 13 containing therein an air supply valve 72 and this tubular housing 13 is formed with cutouts 101, 102 extending orthogonally to a longitudinal axis of the housing 13. A lever 17 interposed between the air supply valve 72 and a diaphragm 10 has its inner end 17B adapted to stride across the housing 13 and to be inserted into the cutouts 101, 102.

Abstract: A regulator for diving includes a pressure regulating means. The pressure regulating means includes a multiple thread screw 87 operatively thread-engaged with a slider 84 which, in turn, is pressed a pressure regulating coil spring 81 so that this coil spring 81 is adjusted from the maximum compressed condition to the minimum compressed condition as the multiple thread screw 87 is fully turned.

Abstract: A Self Contained Re-breathing apparatus with a single bank of oxygen sensors for signaling oxygen contact back to a display and oxygen valve control, where the signal is set via two identical and independent sets of signal control circuitry which are interconnected in a primary and secondary relationship. The primary circuitry controlling the valve and the secondary circuitry sending a signal to a display, wherein the two identical and independent sets of circuitry can perform each role and serve to confirm the satisfactory operation of a master signal processing circuit.

Abstract: In an apparatus and method for examining the pulmonary mechanics of a respiratory system, in order to obtain information about the mechanical properties of the respiratory system's lungs, during an expiration of a flow of gas streaming out of the respiratory system is modulated, the volume of gas streaming out of the respiratory system is determined, the variation in pressure in the respiratory system is determined, and an expiratory pressure-volume relationship is determined from the expiratory volume and the expiratory variation in pressure.

Abstract: The portable ventilators of the present invention provide a hands-free ventilatory support device in critical care, emergency and resource limited environments. The portable ventilators utilize ambient air and include a two dual head compressor system to provide a consistent air supply to the patient. The ventilator device is battery operated and is capable of providing up to 60 minutes of care.

Abstract: This invention concerns a method for open-loop regulation of a breathing aid apparatus, which consists in: constituting a compression chamber (1), by dividing it into two compartments (3, 4) each connected to an intake (5, 7) of air or breathing mixture and to an outlet (6, 8) of compressed air, using an elastic floating diaphragm (2); guiding said floating diaphragm (2) by fixing its periphery to the wall of said chamber (1); fixing a field coil (14) at the centre of said floating diaphragm (2); placing said field coil (14) in an air gap (E) which is oriented in the direction deforming said floating diaphragm (2); measuring the instantaneous flow rate of air leaving through said outlet (6, 8) and powering said field coil (14) continuously calculating the instantaneous intensity and the direction of the supply current on the basis of the set pressure of compressed air, of said instantaneous flow rate and of the constants of said apparatus.

Abstract: A breathing apparatus for a diver is configured to include a second stage pressure regulator and a hollow exhaust tube. An input port is located on a side of the pressure regulator and is attached to a supply hose coming from a tank mounted on a scuba diver's back. Additionally, an exhaust port is located on the same side of the regulator as the input port. The hollow exhaust tube is attached to the exhaust port. The exhaust tube is able to trap gas therein by the placement of one-way valves at each end of the exhaust tube, thus supplying a counteracting buoyant force to the same side of the regulator as the side where the supply hose enters the regulator, while defining an exhaust port arranged so that bubbles leaving the exhaust tube do not obstruct the diver's vision. The regulator may be fit with a supporting surface designed to rest on a diver's chin.

Abstract: Self contained underwater breathing apparatus in which a first stage regulator comprises a body (15) defining an internal dry chamber (20), a first port (25) in the chamber for receiving high pressure gas from a supply cylinder, a valve assembly (12, 13, 26) to reduce the high pressure gas to medium pressure gas in the chamber, a second port (29) for delivering the medium pressure gas to a user, and a hydrostatic transmitter (5) responsive to an increase in ambient water pressure and adapted to move within the body (15) accordingly to increase the supply of medium pressure gas to the user, a pressure transducer (9) with a pressure module (4) and a liquid crystal display module (30) visible to the user to indicate the pressure of the medium pressure gas.

Abstract: A process and system are provided for controlling a respirator with a breathing circuit (2), an inspiration branch (10) and an expiration branch (12), in which the gas components needed for the respiration are fed in by a fresh gas metering device (20) via a fresh gas line (9), as a result of which at least the amount of breathing gas consumed can be replenished. A breathing gas delivery unit (1) is provided in the inspiration branch (10) and with a volume flow sensor (13) in the expiration branch (12). The fresh gas utilization of the respirator is improved and the process and system reduces the resistances in the breathing circuit (2) for the patient (3) by the breathing gas delivery unit (1) being returned during the phase of expiration at a speed that depends on the volume flow that is measured by the volume flow sensor (13).

Abstract: 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 ambient that moves in response to pressure differentials to cause a valve mechanism to introduce breathing gas to the mask. A passage provides breathing gas over said diaphragm exposed to ambient which can be a passage from one side of the diaphragm to the other. A protective cover can overlie the passage which can be displaced upon gas flow through the passage. The method purges ambient contaminants from the diaphragm by providing breathing gas over the diaphragm through an opening of the diaphragm.

Abstract: The present invention is directed to a portable oxygen concentrator system adapted to be transported by a user. The portable oxygen concentrator system includes an energy source, an air separation device powered by the energy source and adapted to convert ambient air into concentrated oxygen gas for the user, at least one sensor adapted to sense one or more conditions indicative of the oxygen gas needs of the user, and a control unit interrelated with the air separation device and the at least one sensor to control the air separation device so as to supply an amount of oxygen gas equivalent to the oxygen gas needs of the user based at least in part upon the one or more conditions sensed by the at least one sensor.

Abstract: An apparatus, method and system for non-invasive breathing assistance to a patient. The apparatus comprises a hose or other gas conduit with a valve. Proximity of the patient to a sensor causes the valve to open, directing a pressurized stream of air or other gas at the patient's mouth, assisting the patient in breathing.

Abstract: A resuscitation valve assembly includes a housing with an inlet port adapted to be connected to a pressurized breathable gas source, such as oxygen, an outlet port adapted to be connected to a patient's airway and an ambient air port. The inhalation chamber is connected to the pressurized gas source when a manually operated valve, within the housing, is open and is disconnected from the inhalation chamber when the valve is closed. An inhalation/exhalation check valve is disposed between the inhalation chamber, the outlet port and the ambient air port to conduct the high pressure gas through the outlet port and into the patient's airway, vent the patient's exhaled gas through the ambient air port and allow ambient air to flow through the outlet port in response to the patient's spontaneous breathing.

Abstract: Self-contained underwater re-breathing apparatus having a breathing circuit, an injection system for adding fresh breathable gas to the breathing circuit, and an automatic control system including a microcomputer for monitoring physical parameters in the breathing circuit and controlling the feeding of breathable gas to the breathing circuit in accordance with said physical parameters. The re-breathing apparatus has a bailout system automatically activated in an emergency, where the breathing circuit is shut off, and the diver starts inhaling directly from the breathable gas supply and exaling to the environment.

Abstract: Automatic control system for a rebreather, the automatic control system comprising sensors, a microcontroller and an indicator, the microcontroller being adapted to analyse readings of the sensors and, when abnormal readings are detected, actuate a bailout, generate a safety instruction to the diver and display this instruction on the indicator. The re-breathing apparatus has a bailout system automatically activated in an emergency, where the breathing circuit is shut off, and the diver starts inhaling directly from the breathable gas supply and exaling to the environment.

Abstract: An improved respiratory analyzer comprises a disposable flow module and non-disposable electronics module. An improved ventilator system comprises a supply of respiratory gases, a ventilator line for directing the respiratory gases to a patient, a flow module holder located in series with the ventilator line into which a flow module can be inserted, and an electronics module which connects to the flow module. In a preferred embodiment, the flow module and electronics module operate in combination to provide the functionality of an indirect calorimeter, so as to determine the metabolic rate of the patient. Feeding of an intubated patient can be controlled using determined patient metabolic rates. Other respiratory parameters can be determined by the system, such as peak flow, tidal volume, end-tidal concentrations, and respiratory quotient. The system provides a non-invasive method of cardiac output determination. A flow module can also be inserted into the mouth or internal respiratory tube of a person.

Abstract: A positive airway pressure assist breathing apparatus or ventilator system has a gas delivery unit, an inspiration line connected to the output of the gas delivery unit for connecting the gas delivery unit to a, patient during an inspiratory phase of each breath, and an expiratory unit for controlling exhausting of gases from the patient during an expiratory phase of each breath. A pressure sensor senses gas pressure in the system, and a control unit controls pressure of gas supplied to a patient in each inspiratory phase based on a pre-set target pressure.

Abstract: An automatically closing ambient air device is disclosed having a generally conical passageway, containing an inlet for the flow of fluid from the ambient environment into the passageway and an outlet for the flow of such fluid from the passageway, and having valve means arranged to close fluid flow through the outlet from the passageway which is actuated by buoyant force and/or gravitational force and/or a combination thereof imposed by a weighted element in response to the spacial orientation of the conical wall of the passageway to level.

Abstract: A regulator assembly is provided for use in a respirator system to supply a regulated flow of air to a respirator head piece. The respirator assembly comprises a housing (15) having an air inlet port (17) for connection to a source of air at comparatively high pressure, and an air outlet port (23) for connection to the respirator head piece. The housing (15) contains an air pressure-reduction stage (19) in communication with the inlet port (17), and a noise-reduction stage (21) between the pressure-reduction stage and the outlet port (23). The noise reduction stage (21) comprises two, spaced, muffler discs (41, 43) the first of which is positioned adjacent the air outlet (39) of the pressure-reduction stage (19). A deflector plate (47) deflects the airflow from the pressure-reduction stage (19) through the first muffler disc (41), and thereby diffuses the air flow before it reaches the second muffler disc (43).

Abstract: A temperature alarm device for a breathing apparatus is described, comprising an air bottle (1) with a main valve (2) to which is connected a hose (3) for supply of air from the air bottle (1) via a reduction valve (4) to a breathing mask (5), wherein the temperature alarm device comprises a temperature controlled sound transmitter that emits a sound when the temperature of the surroundings exceeds a pre-defined temperature. A breathing apparatus comprising this temperature alarm device is also described.

Abstract: 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.

Abstract: A flow sensing apparatus for detecting fluid flow rate and direction is described. The flow sensing apparatus includes a flow-responsive element projecting into the fluid flow path, and a position sensor which detects the degree and direction of any change in position of the flow responsive element in response to the fluid flow.

Abstract: Distributor for underwater breathing apparatus, including: a box-shaped body housing a device for regulating the air flow coming from a source of pressurized air; a tube connected to said box-shaped body and communicating with a mouthpiece; an air intake duct connected to said box-shaped body by an intake valve; and one or more discharge ducts connected to said box-shaped body. The air intake duct includes a structure which induces rotation of the air flow coming from the source of pressurized air, thus reducing its intake speed into the tube connected to the mouthpiece.

Abstract: A method and device for sensing inhalations and controlling the delivery of oxygen or other therapeutic gases to a patient. A flow-through sensor is adapted to provide a method and device to monitor various parameters of a patient's breathing and/or pulse oxygen saturation. Adjustments are made to the bolus delivery from a source of therapeutic gas to efficiently provide appropriate levels of therapeutic gas to the patient and to economically conserve therapeutic gas.

Abstract: A multiple functionality pneumatically controlled medical ventilator provides precision regulation of tidal/forced breathing, and continuous positive airway pressure (CPAP)-based spontaneous breathing capability. The ventilator includes a patient breathing gas coupler that is adapted to be coupled to a patient airway breathing interface, and an input port to which a pressurized breathing gas is coupled, A pressure regulator supplies breathing gas at a positive pressure sufficiently higher than nominal lung pressure to prevent collapse of the patient's lungs. A tidal breathing gas supply unit periodically generates a volume-regulated tidal breathing gas for application to the patient airway breathing interface, while the CPAP valve supplies a pressure-regulated breathing gas to the patient airway breathing interface, in response to a patient demand for breathing gas that is exclusive of the tidal breathing supply.

Abstract: Gas delivery valve, in particular of the demand-valve type, having a valve body (1) in which is made a main passage (11) for routing gas comprising a gas inlet orifice (12) and a gas outlet orifice (13), valve means (33) arranged on the internal passage (11) for routing gas, between the said gas inlet orifice (12) and outlet orifice (13), making it possible to control the flow of gas in the said main internal passage (11) for routing gas, a line (14) for detecting a pneumatic vacuum co-operating with the said valve means (33) in order to allow, at least temporarily, the flow of gas in the said main internal passage (11) for routing gas between the said inlet orifice (12) and outlet orifice (13). The valve further comprises a secondary passage (8) for routing gas which is fluidically connected to the main gas routing passage (11) upstream (11a) and downstream (11b) of the said valve means (33).

Abstract: A valve device for controlled supply of a pressure fluid, comprising a housing (2) having a supply chamber (3) for the supply of a pressure fluid from an inlet (4) connected to a pressure fluid source, and having an outlet (5) communicating with the supply chamber (3) via an outlet valve (6). The valve device comprises a reference chamber (10) connected to the outlet (5) through a narrow, leakage-forming duct (11), a regulating unit (12-14) seeing to it that the supply chamber (3) is kept permanently pressurised at a value just above the pressure in the reference chamber (10), and a control valve (20) having a valve body (21) for opening and closing of a passage (19) between the supply chamber (3) and the reference chamber (10).

Abstract: A method and device for triggering ventilatory support to assist the patient's respiration. Myoelectrical activity of a patient's respiratory-related muscle is sensed to detect respiratory effort, and to produce a myoelectrical signal representative of the sensed muscle myoelectrical activity. Respiratory flow and pressure can also be measured to produce respective respiratory pressure and respiratory flow signals. A logic trigger circuit triggers ventilatory support in relation to the myoelectrical signal, respiratory flow signal and/or respiratory pressure signal to assist respiration of the patient. The amplitude of the myolectrical signal is compared to a given threshold, and ventilatory support is triggered when the amplitude of the myoelectrical signal is higher than this threshold.

Abstract: Embodiments of the present invention described and shown in the specification and drawings include a respiratory system for automatically and variably controlling the supply of a pressurized breathing gas to a patient via a breathing circuit that is in fluid communication with the lungs of the patient. The respiratory system has a demand valve in fluid communication with a source of pressurized gas. The demand valve is switchable between a open position, in which an inhalation conduit of the breathing circuit is in fluid communication with the source of pressurized gas, and a closed position, in which the inhalation conduit is not in fluid communication with the source of pressurized gas. The demand valve is proportionally moveable between the open and closed positions in response to a pressure within a reference chamber which is in fluid communication with the trachea of the patient.

Abstract: An oxygen therapy apparatus for supply of oxygen to patients. The device comprises an inlet port (17) for receiving high pressure oxygen from a cylinder and an outlet port (1) for supplying oxygen to a patient, typically via a single tube cannula (not shown). Three valves control the supply of oxygen to the patient: a diaphragm valve (42) senses the pressure at the outlet (1) and, in particular senses whether the patient is inhaling or exhaling. A valve (36) controls the supply of oxygen to the patient via an inlet jet (25) which is selectably closed by a piston (20) incorporating a flexible seat (24). Movement of the piston (20) is in turn controlled by a pilot valve (37) in dependence on the state of the diaphragm valve (42). The device gives a pulsed output to the patient during inhalation, but shuts off during exhalation to economise on the use of oxygen.

Abstract: In a method of regulating the flow rate of additional oxygen taken from a pressurized inlet for oxygen from a source and admitted into a breathing mask provided with an inlet for dilution ambient air, the ambient pressure and the instantaneous inhaled breathe-in flow rate in terms of volume reduced to ambient conditions are measured in real time. The minimum oxygen content in the complete inhalation phase in order to comply with respiratory standards is computed from the ambient pressure and the instantaneous flow rate of additional oxygen is controlled in such a manner as to satisfy the requirements of the applicable standards with a safety margin that is generally a few percent. There is also described a regulator implementing the above method.

Abstract: A pneumatic oxygen conserving device includes a reservoir of pressurized gas delivered upon inhalation through a single-lumen cannula. Gas flow is interrupted by a series of interconnected passages and chambers, including a check valve which is acted upon by the flow of gas being delivered through the delivery outlet of the device. The device is self regulating to the extent that oxygen pulses of appropriate volume are delivered irrespective of the breathing rate of the user. The device includes a plate with various passages and chambers defined therein in such a way as to reduce the overall length of the device.

Abstract: A demand flow oxygen valve for use with low pressure oxygen sources (about 5 to 75 psi). The inlet of the valve is provided with a diameter index safety system (DISS) oxygen-specific connector. The DISS connector is capable of connecting the inlet of the valve to any oxygen source having a male DISS connector at its outlet. Alternatively, a quick-disconnect connector could be provided to the valve. A single valve may be interchanged among multiple oxygen sources. A method of retrofitting existing oxygen supplies includes steps of providing the demand flow valve having a connector and connecting the valve to the existing oxygen source via the connector. An additional step includes providing a connector adapter if the existing oxygen source does not have a corresponding connector at its outlet.

Abstract: An apparatus and method for a bi-level positive airway pressure support in which the rise time from the expiratory positive airway pressure to the inspiratory positive airway pressure is automatically controlled by the pressure support system. The pressure support system includes a sensor, a control system, and a pressure generating system. The sensor monitors the patient's respiration to detect respiratory events, such as an apnea, hyponea or other disturbance, and the control system responds to the sensor information to adjust the rise time from the expiratory positive airway pressure to the inspiratory positive airway pressure gas pressure to maximize patient comfort and pressure support treatment effectiveness.

Abstract: An automatically closing ambient air device is disclosed having a generally conical passageway, containing an inlet for the flow of fluid from the ambient environment into the passageway and an outlet for the flow of such fluid from the passageway, and having valve means arranged to close fluid flow through the outlet from the passageway which is actuated by buoyant force and/or gravitational force and/or a combination thereof imposed by a weighted element in response to the spacial orientation of the conical wall of the passageway to level.

Abstract: A variable volume ratio compound counterlung is disclosed for use with a semi-closed circuit breathing apparatus. The compound counterlung generally comprises a flexible bag member disposed within and attached to an outer counterlung member. A pair of depth sensors are provided to vary the volume of said flexible bag member with changes in depth. The flexible bag member is driven by the outer counterlung to discharge gas stored within the flexible bag member depending on the diver's respiratory minute volume. The volumetric capacity of the inner counterlung is controlled by one or more ambient pressure sensing devices with an outer bellows-type counterlung that drives the inner counterlung's contents overboard with each breathing cycle.

Abstract: According to the invention, methods and devices for increasing cardiopulmonary circulation induced by chest compression and decompression when performing cardiopulmonary resuscitation are provided. Cardiopulmonary circulation is increased according to the invention by impeding airflow into a patient's lungs to enhance the extent and duration of negative intrathoracic pressure during decompression of the patient's chest. Enhanced extent and duration of negative of intrathoracic pressure thus promotes venous blood flow into the heart and lungs from the peripheral venous vasculature. In one embodiment, impeding the airflow into the patient's lungs is accomplished by placing a ventilation tube in the patient's airway.

Abstract: An emergency life support system including a patient ventilator for mechanical breathing assistance; a capnograph to monitor CO2 for ventilation effectiveness; a pulse oximeter for measuring blood stream oxygen saturation; a carbon dioxide sensor; an electrocardiograph (ECG) to monitor cardiac performance; an infusion pump; and alarms and a data recorder. The preferred embodiment uses an oxygen generator to deliver oxygen, to generate electric power to run the ventilation system, and to warm IV fluids and resuscitated air. The generator has electronically controlled valves and a modified valve system that offers the ability to select the oxygen concentration in the air delivered to the patient.

Abstract: A circuit for use in respiration type apparatus using a piezoresistive transducer and wherein the temperature effects on system stabilization are minimized. In addition, means are provided to reduce system initialization times. The circuit comprises a differential sensor amplifier response to the output of the piezoresistive transducer, a dc negative feedback circuit connected to the output of the differential amplifier, means for reducing the initialization time of the circuit, circuit means for clamping the voltage output and a voltage comparator for tracking the circuit operating point and switching its output state when a sudden voltage change caused by a patient breath is detected.

Abstract: Triplicate Diving Gas Valve Device, comprising: a siren unit, a Life Coat Inflation unit and a User's Respiration Unit. The Siren drives its alarm sounding by reciprocating pounding of piston in a cylinder, by reason of this, the siren will serve its purpose ready submerged in waters or on the surface. The Gas Valve can be used in combination with both the Life Coat and the Respiration Mouthpiece, it can be manipulated manually using one hand expeditiously for triplicate services including: Life Coat Inflation/Deflation, siren alarming appealing for Help, and Respiration-charged air-compression. At a suitable location in the Respiration Mouthpiece is positioned a Flow Division Block serving to block compressed gas that is supplied from the Compression Cylinder, so that the compressed gas is split to pass to flanks on both sides, in that manner safeguarded from charging straight into Diver's throat, so that the diver is relieved from any discomfort while breathing all the while.

Abstract: A demand regulator with air dilution for regulating the pressure and flow of a respiratory gas comprises an inlet for additional gas and an outlet leading to a respiratory mask, and also dilution means. Control means switch a supply of pressurized additional gas between at least two passages. At least one of these passages corresponds to an economy flow and has a restricted cross section for limiting the flow of additional gas transmitted to the inlet. The other passage has a cross section which is such that the additional gas has a maximum flow in order to supply the user with additional gas in a physiologically sufficient manner.