Abstract: 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.

Abstract: A molecular sieve type gas separation apparatus (10) for separating product gas from a gas supply (14) includes at least one sieve bed (11-13) which during an adsorption charge phase of a cycle, adsorbs non product gas in the gas supply (14), and in a desorption regeneration phase of the cycle desorbs the previously adsorbed non product gas. The apparatus further includes an outlet (18) to which product gas is delivered during the adsorption charge phase, and an outlet (31) for non product gas during the desorption regeneration phase. A sensor (36) responsive to the concentration of a constituent in the product gas, and a control (20) to switch the apparatus (10) between the adsorption charge and desorption regeneration phases are further provided. The control (20) is adapted to adjust the duration of adsorption charge phase relative to the duration of the desorption regeneration phase in each cycle.

Abstract: A method of controlling a fluid in a life support system including at least one of a G-suit and a counterpressure garment including utilizing a control system comprising a control valve having a moveable part which is moved by an actuator in response to an input to the control system to operate the valve to bring a parameter of the fluid towards a desired value, the input being conditioned to provide a control signal to cause the actuator to move the moveable part of the valve and wherein the method comprises conditioning the input by comparing the input with reference information relating to the position of the moveable part of the valve, and when the comparison indicates that the position of the moveable part of the valve is not at a desired position, issuing the control signal incrementally to move the moveable part and updating the reference information so that the updated reference information is available for future comparison with the input.

Abstract: An ionic conduction device comprises a stack of layers, each layer comprising an electrolyte membrane having a pair of opposed surfaces, a gas permeable electrode in contact with each opposed surface, and there being a plurality of interconnects in electrical contact with the electrodes of the layers, to provide electrical continuity through the stack, wherein there is at least one gas flow path though the layers and the interconnects of the stack.

Abstract: An assembly for retaining a catch member in a first condition and for releasing the catch member for movement to a second condition, the assembly including a latch member pivotable about a first pivotal axis and having a formation adapted to co-operate with the catch member to retain the catch member when the latch member is in a latched position, and a rocker member pivotable about a second pivotal axis, the latch member and the rocker member interacting to retain the latch member in its latched position, the assembly further including actuating means to move the rocker member about the second pivotal axis to cause the latch member to be pivoted about the first pivotal axis to an unlatched position to release the catch member, and wherein the latch member and the rocker member are interconnected by a resilient biasing means wherein the resilient biasing means includes first and second relatively movable parts with a spring acting between them and there being a stop means which locks the first and second rela

Abstract: A molecular sieve type gas separation apparatus (10) for separating product gas from a gas supply (14) includes at least one sieve bed (11-13) which during an adsorption charge phase of a cycle, adsorbs non product gas in the gas supply (14), and in a desorption regeneration phase of the cycle desorbs the previously adsorbed non product gas. The apparatus further includes an outlet (18) to which product gas is delivered during the adsorption charge phase, and an outlet (31) for non product gas during the desorption regeneration phase. A sensor (36) responsive to the concentration of a constituent in the product gas, and a control (20) to switch the apparatus (10) between the adsorption charge and desorption regeneration phases are further provided. The control (20) is adapted to adjust the duration of adsorption charge phase relative to the duration of the desorption regeneration phase in each cycle.

Abstract: An oxygen generating device (11, 211) to which a gas mixture containing oxygen is fed, and which is operable to separate the gas mixture into oxygen rich and oxygen depleted gas components, the device (11, 211) including a negative temperature coefficient material (36a 36b 36c; 236) which is active at an elevated temperature above a minimum operating temperature, to separate the gas mixture into oxygen rich and oxygen depleted gas components, there being an electronic control unit coupled to the device to pass an electrical current through the device (11, 211) to produce a heating effect within the device to heat the gas mixture at least towards the minimum operating temperature wherein the device includes a plurality of active sections (A, B, C) through each of which the gas mixture passes in turn, and the electrical current supply is connected to each of the sections (A, B, C) so that the sections electrically are connected in series.

Abstract: A method of controlling an oxygen generation device of the kind including a ceramic membrane through which an electrical current is passed whilst ambient air is supplied to one side of the membrane, the membrane allowing oxygen in the supplied air to diffuse therethrough by ionic transport when the membrane is at or above an operating temperature, at a rate dependant upon the electrical current, there being a plenum or the like to recover the oxygen at a second side of the membrane, the method comprising regulating the electrical current passing through the membrane by switching the electrical current on and off and varying the proportion of current-on time in a given time interval (t) in dependence upon a feedback signal.

Abstract: A canister for containing a bed of particles, for example sorbent particles, which includes a loading device for applying a predetermined compressive load to the bed of particles and an adjusting device for automatically adjusting the loading device to maintain substantially the predetermined compressive load. The adjusting device functions in conjunction with the pressure of an operating fluid in the canister.

Abstract: A two-way check valve for a breathing gas supply assembly, comprises a body, a first inlet in the body for receiving a normal breathing gas flow, an outlet for delivering a gas flow from the body, first passage means communicating the first inlet with the outlet, second passage means communicating the second inlet with the outlet, a valve member mounted internally of the body so as to be movable between a first position in which it closes communication between the second inlet and the outlet and a second position in which it closes communication between the first inlet and the outlet, and resilient means biasing the valve member towards the first position.

Abstract: Air-oxygen mixture control apparatus includes a pressure control valve arrangement for substantially equalizing the pressures of oxygen and air supplied to the apparatus at variable pressures. A volume flow control arrangement produces volume flows of oxygen and air appropriate for mixing to provide gas of desired oxygen concentration to a breathing demand regulator for breathing by an aircraft aircrew member. An aneroid acts to occlude the supply of air when the aircrew member is exposed to low aircraft ambient atmospheric pressure so that undiluted oxygen is made available for breathing. The apparatus overcomes the problem of mixing oxygen with air when either one or both is supplied from a variable pressure source, such as is the case when high pressure air from a compressor stage of a gas turbine engine is used for dilution purposes.

Abstract: This invention provides an industrial cassette recorder including mechanisms for removing a cassette undamaged in the event of the failure of an electrical supply. The remaining mechanism automatically moves a cassette from a loading position to an unloaded position and releases a pinch roller. An electric motor is utilized as a generator to facilitate take up of slack tape.

Abstract: Inflation pressure of an aircrew G-suit is set by a servo-pressure which controls movement of inflation gas supply and vent valves 126 and 127, respectively. Servo-pressure is regulated by a torque motor controlled valve 124, 125 which receives a servo-demand signal from an electronic control unit (ECU) 123. The ECU receives an inflation pressure demand signal P.sub.DEM from an aircraft systems computer 120 which stores schedules of G-suit inflation pressure against increasing acceleration and decreasing cabin ambient pressure. The computer is programmed to look-up and output the higher one of values for inflation pressure dependent upon values of acceleration signals G.sub.Z and cabin ambient pressure signals P.sub.AMB input to the computer by sensors 121 and 122, respectively. The ECU compares an existing G-suit inflation pressure P.sub.

Abstract: A breathing gas regulator for regulating delivery of breathing gas to an aircrew member wearing a liquid filled G-suit includes a relay valve having a diaphragm mounted valve plate for sensing G-suit hydrostatic pressure. A bleed of breathing gas is supplied to the relay valve by way of a pneumatic link and is vented to ambient through a vent outlet. As G-suit hydrostatic pressure rises due to increasing G-load the valve plate moves towards closing the vent outlet. Above a predetermined G-load, with the vent outlet closed, a pneumatic signal is generated in the pneumatic link and is applied to an end face of a valve controlling outflow from a breathing-pressure control chamber so that pressure in the control chamber increases to set a breathing gas pressure at the regulator outlet appropriate to positive pressure breathing.

Abstract: The oxygen content of oxygen-enriched air is monitored by a solid electrolyte amperometric sensor which does not require a reference gas for comparison with the oxygen-enriched air. When oxygen-enriched air is supplied to the sensor a current signal is output by the sensor. The current signal is converted to a voltage signal which is processed by a signal processor storing an oxygen diffusion equation in the form of a look-up table to obtain an oxygen percentage concentration signal. An oxygen partial pressure signal may be obtained by supplying ambient pressure signals from an ambient pressure sensor to the signal processor for multiplication with the oxygen concentration signal.

Abstract: A fluid compressor includes a plurality of compression stages each operated sequentially by drive means comprising a pneumatically operated drive piston operating in a drive cylinder. Several embodiments are described and illustrated having different forms of control means and drive and sequencing means for the drive pistons.

Abstract: A sonobuoy dispenser including a rotatable tubular cylinder having a plurality of adjustable sonobuoy support members longitudinally of its external surface is rotated and indexed by a power source and a Geneva mechanism controlled by a fiber optic switch members and an electronics control circuit further includes release for selectively releasing the sonobuoys.

Abstract: Oxygen-enriched breathable gas for breathing by aircrew is delivered by an on-board oxygen generating system 11 utilizing molecular sieve adsorber beds 12. The breathable gas is compressed by a compressor 17 and supplied by way of an appropriately switched two-way valve 25 to a plenum storage tank 30 from which it is withdrawn for breathing by aircrew during normal flight operations. The two-way valve may be switched by electronic control means 15 to connect the compressor with an aircrew seat mounted emergency storage bottle 40 when breathable gas of maximum oxygen concentration is being delivered by the OBOGS and the pressure in the emergency storage bottle is sensed to have fallen below a designated value. This reduces the system servicing requirements and minimizes the size of the system components, in particular the adsorber beds.

Abstract: An on-board oxygen generating system (OBOGS) includes a molecular sieve oxygen generating system (MSOGS), a breathable gas delivery regulator selectively operable to deliver 100 percent MSOGS output gas or air diluted output gas to a user, a back-up storage plenum and control means arranged so that when air diluted delivery gas is selected a portion of 100 percent MSOG output gas is diverted to charge the storage plenum and when 100 percent MSOG output delivery gas is selected diversion to the storage plenum is automatically prevented. The breathable gas delivery regulator includes an injector adapted to induce a flow of air to mix with 100 percent MSOG output gas when air diluted delivery gas is selected.

Abstract: The temperature range for stable operation of a flueric partial pressure sensor (300) is improved by temperature-responsive means (80, 60) which vary with temperature change the suction applied by a flueric aspirator (27) in drawing gas through sensor bridge legs (12, 13) and a power line (37) of a flueric amplifier (11). The temperature-responsive means may comprise temperature-sensitive adjustment means (107, FIG. 2) embodied in a pressure reducing valve (80) to vary the pressure of working gas supplied by way of delivery line (28) for driving the flueric aspirator. Alternatively or additionally the temperature-responsive means may comprise a temperature-sensitive bleed valve (60) incorporated in a common outlet (14) from the bridge legs and the flueric amplifier power line.