Abstract: A case for a rechargeable electrochemical cell comprises a vent disposed in the case interior, the vent including an oxygen/hydrogen recombination catalyst for catalyzing the recombination of the hydrogen produced by the cell during the recharge mode with oxygen in the case interior to form water in the case interior. The vent comprises a vent support extending inwardly from the cell case shell, a gas permeable, electrolyte impermeable vent cover membrane adjacent the interior surface of the vent support, and a foraminous catalyst support disposed in the case adjacent the interior surface of the vent cover membrane so that the vent cover membrane is sandwiched between the catalyst support and the vent support. Oxygen from the ambient air permeates the vent cover membrane and recombines with the hydrogen in the cell case interior. A rechargeable electrochemical cell comprising the cell case is encompassed and the cell is desirably a metal-air cell.

Abstract: The present invention provides a system for venting gas from within a case housing a metal-air cell having a cathode and an anode with a separator positioned therebetween. The cell has at least one gas vent on the anode side of the separator that extends from the interior surface of the case to the exterior surface. Each gas vent has a gas vent cap thereon on the interior surface of the case. A gas permeable, hydrophobic membrane is positioned between each gas vent and gas vent cap. The gas vent, with the gas vent cap positioned thereon, prevents the anode from blocking the venting of gas through the membrane.

Abstract: A method and apparatus for measuring the lift generated by airfoils of an aircraft. This real-time analysis is accomplished by measuring a differential pressure between the upper and lower lift surfaces of the airfoils. The system comprises the steps of: a) measuring an actual differential pressure between the upper and lower lift surfaces for a given aircraft speed, b) transmitting this actual differential pressure measurement to a computer, c) comparing the actual differential pressure measurement with an optimal pressure differential for the same aircraft speed. The apparatus comprises a fixed array of differential pressure sensor mechanisms for measuring actual pressure differentials and a computer for comparing optimal differential pressure measurements to the actual differential pressure measurements. Each sensor mechanism preferably contains a piezoelectric sensor that communicates with the upper and lower lift surfaces.

Abstract: A metal-air battery leakage detector is disclosed which uses a wicking material to absorb and propagate leaking electrolyte to a leak detection means so that the detection means is activated regardless of whether the leak is occurring in the vicinity of the detection means. In a first embodiment a substance that chemically reacts with electrolyte to change color is impregnated into the wicking material as the leak detection means. In the second embodiment electrodes are embedded in the wicking material and wired to an electrical circuit that is responsive to the presence of electrolyte as the leak detection means. In either case, a user has immediate knowledge of an electrolyte leak occurring inside a battery casing so that the battery can be removed from service before the leaking electrolyte can cause harm.

Abstract: A vent system for exhausting gas generated within a battery case is provided. The vent system exhausts gas from the battery case while maintaining the hermetic seal of the case. The vent system provides a small gas exit hole that is sufficiently small to prevent electrolyte leakage and also intake of excess carbon dioxide or excess water vapor from the atmosphere. Also, various combinations of gas-permeable, hydrophobic membranes and diffuser material may cover the gas exit hole to provide humidity control for the battery while exhausting gases from the battery. A recess may be provided within the case such that the gas exit hole communicates between the atmosphere and the recess. Also, various combinations of gas-permeable, hydrophobic membranes and diffuser material may cover the recess and gas exit hole to provide humidity control for the battery while exhausting gases from the battery case.

Abstract: An air manager system is disclosed which maintains a more stable water vapor and carbon dioxide equilibrium across the air cathode of a metal-air cell while still providing new oxygen needed for operation of the cell at desired power levels. Oxygen is preferentially drawn in through one or more ventilation openings in a housing, so that the concentrations of water vapor and carbon dioxide in the battery housing remain more stable, resulting in less transfer across the cathode. A fan circulates the gases within the battery housing, keeping the oxygen needed for operation of the cell in contact with the air cathode even though the oxygen concentration within the housing is reduced compared to the ambient air outside the housing. Therefore, the cell is less susceptible to drying out or flooding, and less carbon dioxide intrudes into the cell.

Abstract: A metal-air power supply which provides improved control over air flow is provided. The reactant air and cooling air inlets are separate from one another and isolated from the exhausted reactant and cooling portions of the air flow. The reactant air flow is limited to a volumetric flow rate sufficient to provide from about 3 to about 10 times the stoichiometric amount of oxygen necessary to produce a predetermined level of current from the cell, and a total volumetric flow rate of air sufficient so that the cooling portion of the air flow has a volumetric flow rate from about 10 to about 1000 times the volumetric flow rate of the reactant portion of the air flow is provided.

Abstract: A cathode cover for a metal-air cell of the type having an air cathode positioned along an external surface of a cell case provides for improved control over exposure of the air cathode to air. The cathode cover allows a sufficient amount of air to the air cathode for an adequate production of power from the cell but limits the amount of air to which the air cathode is exposed so as to prevent premature failure of the cell from flooding, drying out, or contamination. In addition, the cathode cover avoids the problems of point diffusion of oxygen through the air cathode and localized electrolytic reactions. The cathode cover includes a mask member defining a plurality of openings therethrough and forming at least one substantially unobstructed air chamber between the mask member and the air cathode. The mask member includes at least about three of the openings per square inch of the air cathode and the openings provide between about 0.001 and about 0.

Abstract: A bifunctional air-electrode for use in electrochemical energy cells discharges a satisfactory current on the first discharge cycle and operates for a relatively large number of charge-discharge cycles without gas forming between the electrolyte side of the air electrode and the electrolyte. The active layer of the electrode includes an oxygen reduction catalyst having a first oxygen evolution potential and an oxygen evolution catalyst having a second oxygen evolution potential less than the first oxygen evolution potential, the oxygen reduction catalyst being present in a greater concentration proximate the electrolyte side than proximate the air side and the oxygen evolution catalyst being present in a greater concentration proximate the air side than proximate the electrolyte side.

Abstract: A halogenated hydrocarbon recycling machine M1 comprising a cylinder-emptying apparatus including means for transferring a vapour mixture from a cylinder 10 to a fluid storage reservoir R1, a cylinder-filling apparatus including means for filling the cylinder 10.sup.1 from the reservoir R1 and a fluid separating apparatus including means for separating from the vapour mixture of an emptied cylinder, a reusable halogenated hydrocarbon fluid for use by the cylinder filling apparatus.

Abstract: A foldable knife (10) comprises a handle (14), a blade (12), means (24) for securing the blade (12) to the handle for pivotal movement between a closed position wherein the cutting edge (20) is received in a recess (34) in the handle (14) and an open position wherein the cutting edge edge (20) is exposed, a bar spring (16) secured at one end to the handle (14) in the recess (34), and a mechanism (18) secured in an opening (58), (60) in the handle (14) and extending through a hole (44) in the bar spring (16), the mechanism (18) comprising an enlarged portion (48) and a reduced portion (b 50), and means (54) for moving the mechanism (18) between a locking position when the enlarged portion is in the hole (44) for limiting movement of the bar spring (16) for preventing movement of the blade (12) and a release position wherein the reduced portion (50) is in the hole (44) and sufficient movement of the bar spring (16) is accommodated for moving the blade (12) to the closed or opened positions.

Abstract: In a peripheral exhaust system for a high velocity dryer having dryer hood sections and respective supply and removal ducts associated with each section through which recirculating air used for drying is carried to and away from the sections, auxiliary exhaust ducts formed along the periphery of the sections adapted to receive a portion of the hot air used for drying that would otherwise enter the area surrounding the dryer hood and a portion of the cold air from the surrounding area that would otherwise enter the dryer hood. The exhaust ducts are connected by blowers to ducts which remove the air to a location remote from the web.

Abstract: A system for optimizing the thermal efficiency of a dryer in which infrared radiation from a source outside the moisture carrying duct is directed into the duct to subject it to the action of the moisture-laden air in the duct to produce resultant radiation which is detected. In response to the detection, the flow of exhaust and fresh air is regulated to hold the moisture content of the air in the duct to a set value considered to be the optimum for the highest thermal efficiency of the dryer loop.