Abstract: A control device for molecular sieve on-board oxygen generating systems measures both temperature and pressure of the inlet air of an oxygen generating system. An electronic control unit applies pressure limits to a pressure measurement signal and combines it with a temperature measurement signal to produce a composite analog signal responsive to both temperature and pressure inlet air conditions. This analog signal is linearly converted to a frequency signal, whereupon the frequency signal is divided by a constant in order to produce a drive signal for control of the absorb/vent bed cycle valves. Composition control is achieved by venting product mixture as required. Inlet air pressures down to 5 PSIG (pounds per square inch gauge) produce correct system operation, and the quantity of conditioned air required is automatically limited so that system efficiency is higher than prior art systems.

Abstract: A gas mixing pressure regulator for a closed circuit breathing apparatus comprises a first inlet to provide pressurized air to the breathing apparatus, a pressure responsive demand valve for opening and closing a first inlet, a second inlet for supplying carbon dioxide-free exhaled air from the breathing apparatus, and a mixing chamber for mixing the pressurized air and exhaled air for supplying breathable air to the breathing apparatus. The demand valve is isolated from the mixing chamber by a check valve injector nozzle to prevent contamination thereof and is responsive to pressure demands from the breathing apparatus to ensure reliability, stability and long life.

Abstract: An oxygen regulator for controlling the flow of breathing oxygen and uncontaminated air at various altitudes includes a balanced oxygen valve (20) and a balanced air valve (50) which cooperate with a dilution aneroid valve (62) to provide breathable mixture whose oxygen percentage increases with altitude to a predetermined altitude. Above that altitude one hundred percent oxygen is provided. A gas loading aneroid valve (110) operates to increase the oxygen pressure in accordance with altitude over a range of altitude.

Abstract: An oxygen regulator for supplying a recipient with breathable fluid in response to an inhalation demand. A diaphragm which is responsive to the inhalation demand operates a balanced oxygen valve to allow pressurized oxygen flow into a mixing chamber. The flow of pressurized oxygen into the mixing chamber draws air into the mixing chamber through an altitude responsive valve. The pressurized oxygen and air are combined in the mixing chamber to create a volume of breathable fluid sufficient to meet the inhalation demand of the recipient.

Abstract: Well pumping method and apparatus by means of which the liquid level and, correspondingly, the hydrostatic pressure, in a bore hole or well casing, is controlled by means of a vertically adjustable sump for receiving liquid from the bore hole or casing before it is pumped to the surface, the sump having therein a pump which is actuated by the liquid level in the sump so that liquid cannot rise in the bore hole or casing above the top or inlet of the sump, as the liquid enters the sump at this point and is pumped to the surface from the sump, the operation being such that the liquid level in the bore hole or casing is controlled by vertically positioning the sump so that the height of the column of liquid in the casing or borehole above the point where liquid is coming from the formation can be maintained at a minimum with consequent increase in the differential hydrostatic pressure between that in the well bore and that in the formation in the direction of the well bore, enabling the maximum rate of liquid en

Abstract: An oxygen regulator for supplying a recipient with breathable fluid in response to an inhalation demand. A diaphragm which is responsive to the inhalation demand operates a balanced oxygen valve to allow pressurized oxygen flow into a mixing chamber. The flow of pressurized oxygen into the mixing chamber draws air into the mixing chamber through an altitude responsive valve. The pressurized oxygen and air are combined in the mixing chamber to create a volume of breathable fluid sufficient to meet the inhalation demand of the recipient.

Abstract: In an aircraft breathing system a sensor assembly for monitoring the concentration of oxygen in a source of breathable fluid supplied to a recipient. The sensor assembly has a housing with a chamber therein connected by a conduit to the source of breathable fluid. A restricted orifice member in the conduit allows a sample of the breathable fluid to continually flow into the chamber while an exit port in the housing allows the sample of breathable fluid to flow to the surrounding environment. A sensor responsive to the partial pressure of oxygen is connected to the chamber. The sensor in response to the partial pressure of the oxygen produces an operational signal. The operational signal activates an indicator to provide the recipient with a reading of the concentration of oxygen in the breathable fluid. An aneroid fixed to the housing has a face that engages a seat surrounding the exit port.

Abstract: An emergency breathing system has an anti-suffocation valve located in a housing between a source of breathable fluid and a distribution mask. The housing has a chamber which is connected to the distribution mask and an opening which connects the chamber with the surrounding environment. The anti-suffocation valve responds to an inhalation demand of a recipient to allow air from the surrounding environment to enter the chamber and satisfy the inhalation demand of a recipient to allow air from the surrounding environment to enter the chamber and satisfy the inhalation demand. A hydrophobic filter surrounds the opening and prevents the entry of any water present in the surrounding environment into the chamber which could inhibit cyclic inhalation of breathable fluid by the recipient.

Abstract: In a cryogenic cooler, wherein a fluid under pressure is transmitted through an expansion orifice in a nozzle into an expansion chamber at a rate which is controlled by the movement of a needle valve in the expansion chamber, an expander member extends from the nozzle and carries the needle valve. The expander member expands and contracts in response to the temperature in the expansion chamber at a different rate than the needle valve to automatically regulate the flow of fluid into the expansion chamber.