Abstract: A system for identifying the time remaining for a bottled gas supply to lapse. Such bottled gas supplies include those used for gas grilles, scuba, nitrogen for electron microscopes, and any other environment in which a bottled gas is used. The system reads the pressure and optionally the temperature of the gas container, the readings of which are read by a microprocessor, optionally first pre-processed in a conversion module, and converted into a display for the user identifying the time during which the gas contents remaining will last. In various systems, it may be desirable to program the microprocessor, such as with input from a keyboard and/or cd-rom, with parameters regards specifics of the gas or the container, or to simply processing by assuming a certain temperate correlation and thereby eliminate the need for a temperature transducer.

Abstract: A system for identifying the time remaining for a bottled gas supply to lapse. Such bottled gas supplies include those used for gas grilles, scuba, nitrogen for electron microscopes, and any other environment in which a bottled gas is used. The system reads the pressure and optionally the temperature of the gas container, the readings of which are read by a microprocessor, optionally first pre-processed in a conversion module, and converted into a display for the user identifying the time during which the gas contents remaining will last. In various systems, it may be desirable to program the microprocessor, such as with input from a keyboard and/or cd-rom, with parameters regards specifics of the gas or the container, or to simply processing by assuming a certain temperate correlation and thereby elinimate the need for a temperature transducer.

Abstract: A system useable in a jet aircraft having installed therein a pressurized oxygen supply which feeds oxygen into the interior of the plane when it flies at high cabin altitudes, the system indicating the changing status of the supply as oxygen is drained therefrom. The system includes a pressure transducer coupled to the supply and means associated with the transducer to determine the lapse rate at which the pressure of the supply is reduced as oxygen is drained therefrom to yield a first signal representing this pressure lapse rate, and to concurrently determine the lapse rate at which the number of liters of oxygen in the supply is reduced as oxygen is drained therefrom to yield a second signal representing the liter lapse rate. These signals are applied to a microprocessor in whose data base is entered the total oxygen inventory of the supply and the oxygen demand of the plane in which the supply is installed.