Abstract: A ceramic element is provided which can be injection molded from an electrolyte and a binder. The ceramic element includes a tube support portion and a plurality of tubes extending from the tube support portion. The plurality of tubes are arranged in rows and columns. A plurality of vias extend from one surface of the tube support portion to an opposite surface of the tube support portion. The ceramic element is coated with an electrically conductive coating and a current collector coating. The vias are coated with the electrically conductive coating and plugged. After the coatings are removed in selected areas of the ceramic element, the tubes of the ceramic element form a series-parallel array because tubes in the same column are connected in parallel electrically and tubes in adjacent rows are connected in series electrically. Two ceramic elements are sealed together to form a modular electrochemical device. The electrochemical device can be either an oxygen generator or a fuel cell.

Abstract: A ceramic element is provided which can be injection molded from an electrolyte and a binder. The ceramic element includes a tube support portion and a plurality of tubes extending from the tube support portion. The plurality of tubes are arranged in rows and columns. A plurality of vias extend from one surface of the tube support portion to an opposite surface of the tube support portion. The ceramic element is coated with an electrically conductive coating and a current collector coating. The vias are coated with the electrically conductive coating and plugged. After the coatings are removed in selected areas of the ceramic element, the tubes of the ceramic element form a series-parallel array because tubes in the same column are connected in parallel electrically and tubes in adjacent rows are connected in series electrically. Two ceramic elements are sealed together to form a modular electrochemical device. The electrochemical device can be either an oxygen generator or a fuel cell.

Abstract: A method of controlling an oxygen concentrator having a first sieve bed operated over successive control periods according to a duty cycle for alternately pressurizing and flushing the first sieve bed and a second sieve bed operated over the successive control periods according to a reciprocal of the duty cycle is disclosed. The duty cycle and the reciprocal duty cycle are adjusted during every second one of the successive control periods to change the pressurizing relative to the flushing of the first sieve bed and to change the flushing relative to the pressurizing of the second sieve bed, for reducing concentration of oxygen produced. The duty cycle and the reciprocal duty cycle are adjusted during remaining control periods to change the flushing relative to the pressurizing of the first sieve bed and to change the pressurizing relative to the flushing of the second sieve bed, such that water vapor is purged from the first and second sieve beds after pressurizing thereof.

Abstract: A rate of change in altitude computer for providing a pilot with information to safely operate an aircraft. A beam of light is communicated through a mask. A gear responsive to altitude rotates the mask. A photocell receives the beam of light as it passes through the mask to produce sinusoidal wave signals. The positive node of the sinusoidal wave signal is modified to activate a transistor which allows a capacitor to be charged for a time period equal to the positive node. During the negative node of the sinusoidal wave signal the capacitor discharges. When the voltage associated with the charging and discharging of the capacitor is averaged, a steady state voltage is produced. The steady state voltage, which is proportional to the rate of rotation of the mask, drives a dial of an indicator to provide an operator with visual information relating to instantaneous rate of changes in altitude.