The United States of America As Represented by the United States

The United States of America As Represented by the Administrator of the

Durel Corporation

Products of Advanced Technology, Inc.

William J Kerwin

J Byron McCormick

John Dimeff

Craig Hosterman

Steven W Depp

Douglas J Hamilton

Ronald E Bobbett

An inverter includes a fourth order impedance network coupled between the output and the input of an amplifier, causing the inverter to oscillate and produce a high voltage at an output of the impedance network. The impedance of one portion of the impedance network is preferably at least ten times the impedance of a second portion of the impedance network at the frequency of oscillation.

Transformerless high voltage inverter using a fourth-order impedance network

A device for indicating and preventing damage to voltage cells such as galvanic cells and fuel cells connected in series by detecting sequential voltages and comparing these voltages to adjacent voltage cells. The device is implemented by using operational amplifiers and switching circuitry is provided by transistors. The device can be utilized in battery powered electric vehicles to prevent galvanic cell damage and also in series connected fuel cells to prevent fuel cell damage.

Automatic voltage imbalance detector

An adjustably positionable element having a curved end plate is located in proximity to the conventional rupturable curved disc in a pressure relief valve for high pressure cylinders. The end plate serves as one plate of a capacitor and the curved disc serves as the other plate. Impedance variation responsive circuitry senses any change in impedance of the capacitor due to a change in flex of the curved disc brought about by a variation in pressure within the cylinder to which the relief valve is attached. The change in impedance is calibrated to provide an indication of the actual pressure within the cylinder.

Pressure relief valve with pressure indicating means

An integrated thermionic device suitable for use in high temperature, high radiation environments. Cathode and control electrodes are deposited on a first substrate facing an anode on a second substrate. The substrates are sealed to a refractory wall and evacuated to form an integrated triode vacuum tube.

High temperature electronic gain device

High efficiency, multi-dimensional thin film vacuum tubes suitable for use in high temperature, high radiation environments are described. The tubes are fabricated by placing, as by photolithographic techniques, such as are used in solid state integrated circuits, thin film electrode members in selected arrays on facing interior wall surfaces of an alumina substrate envelope. Cathode members are formed using thin films of triple carbonate. The photoresist used in photolithography aids in activation of the cathodes by carbonizing and reacting with the reduced carbonates when heated in vacuum during forming. The finely powdered triple carbonate is mixed with the photoresist used to delineate the cathode locations in the conventional solid state photolithographic manner. Upon high temperature forming (1000.degree. C) the barium, etc. is formed at the surface. Anode and grid members are formed using thin films of refractory metal. Electron flow in the tubes is between grid elements from cathode to anode as in a conventional three-dimensional tube. Both circular geometry for average requirements as well as a repeated linear structure for increased current and power handling capability are employed.

Growing community of inventors

Tucson, AZ, United States of America

William J Kerwin