Other

Voyager Technologies, Inc.

Trek, Inc.

American Telephone & Telegraph Co., At&t Bell Laboratories

Peter R Bossard

Robert H Dunphy, Jr

John A Mucha

Michael R Betker

Charles Hagen

Jerry Kieres

Kevin D Brown

A simple hydrogen generator system for maintaining zero PSI across the proton exchange membrane while generating ultra pure hydrogen gas at high pressure from water. The system includes a proton exchange membrane across which an electrolysis reaction is induced, thereby producing hydrogen gas on a first side of the proton exchange membrane and oxygen gas on a second side of the proton exchange membrane. The current source used to induce the electrolysis reaction is computer controlled so as to maintain a near constant pressure of hydrogen, even as hydrogen is drawn from the assembly. By minimizing the pressure differential across the proton exchange membrane, a more durable and efficient hydrogen generator is produced.

Hydrogen generator with feedback control

An assembly for separating molecular hydrogen from a volume of gas. The assembly includes a first conduit through which a gas at a first pressure flows, wherein the gas at least partially contains hydrogen. A second conduit intersects the first conduit. The second conduit is maintained at a pressure less than the first pressure of the first conduit. A hydrogen permeable membrane is disposed within the second conduit, wherein the membrane prevents the gas from flowing directly into the second conduit. Since the membrane is hydrogen permeable, a predetermined flow rate of hydrogen permeates through the membrane into the second conduit. The hydrogen permeable membrane contains a layer of hydrogen permeable material. The layer of hydrogen permeable material has a top surface and a bottom surface. A first metal mesh element is bonded to the top surface of the layer of hydrogen permeable material. Similarly, a second metal mesh element is bonded to the bottom surface of the layer of hydrogen permeable material, wherein the hydrogen permeable material is deformed into the second metal mesh. The mesh element supports the thin hydrogen permeable layer and prevents it from rupturing or collapsing.

Method and apparatus for purifying hydrogen

A looped circuit for generating a variable bias voltage. The looped circuit includes a variable current source having a current output that is dependent upon the variable bias voltage. The looped circuit also includes a capacitor that is periodically coupled to the current source for a predetermined period of time, wherein the current source charges the capacitor during each predetermined period of time. At least one subcircuit is provided for varying the variable bias voltage, wherein the variable bias voltage automatically causes the current source to charge the capacitor to a predetermined reference voltage during each predetermined period of time. Accordingly, the generated bias voltage will vary with temperature and other external variables. However, the ratio of the current produced by the current source divided by the capacitance of the capacitor is equal to the ratio of the predetermined reference voltage divided by the referenced predetermined period of time. This ratio remains constant regardless of variations in process and temperature.

Looped circuit and associated method for controlling the relationship

A gas flow restriction device for restricting the flow rate of heated gas in a conduit. The flow restriction device is essentially a two piece assembly that includes a valve housing and a valve gate structure that sits within the housing. The valve housing has a first end, a second end and an open central passage extending from the first end to the second end. The open central passage includes a internally tapered section proximate its first end and an internally threaded section proximate its second end. The valve gate structure has a first end a second end, a externally tapered section proximate its first end and an externally threaded section proximate its second end. The valve gate structure passes into the open central passage of the valve housing so that the externally tapered section of the valve gate structure is disposed a predetermined distance within the internally tapered section of the valve housing. At this location, the externally threaded section of the valve gate structure engages the internally threaded section of the valve housing. By rotating the valve gate structure, the threaded interconnection is effected and the valve gate structure moves in relation to the valve housing.

High temperature gas flow rate restrictor device

Apparatus for determining the physical uniformity of a charged drum surface wherein current signals are induced in sensing electrodes in response to variation in drum surface charge. The sensing electrodes are on a detector assembly which is movable toward the drum for inspection of the surface and movable away from the drum after inspection when the drum is to be ejected from the apparatus. The detector assembly is movable through another degree of freedom to accommodate irregularities in drum geometry encountered during rotation thereof. The detector assembly also is provided with structure for maintaining a predetermined spacing of the sensing electrodes from the drum surface during relative movement therebetween. The drum is received, held, and rotated by co-operation between a drum retention assembly and a drum clamping mechanism. The retention assembly includes an arrangement of retainer arms which contact the drum inner surface and which are collapsed in response to forcible engagement of the drum by the drum clamping mechanism to allow rotation of the drum. The drum clamping mechanism is adjustable in two directions to accommodate various drum geometries, and it is movable away from the drum after inspection when the drum is to be ejected. An eject mechanism operatively associated with the drum retention assembly moves an inspected drum out of the apparatus to allow entry of a next drum to be inspected.

Apparatus for electrically inspecting the surface of a drum

A surface capable of holding electrical charge wherein at least one sensing electrode having an edge is located in close physical proximity to the surface and is disposed so that upon relative movement between the surface and sensing electrode, charge on the surface crosses the edge of the electrode. The sensing electrode has a surface area facing the surface which is sufficiently small so as to minimize electrical noise when the electrode is in close proximity to the surface. Electrical charge is applied to the surface and relative movement is provided between the surface and sensing electrode while maintaining a constant distance therebetween. A current signal is induced in the sensing electrode in response to a variation in the surface charge crossing the edge of the electrode, and the signal is detected and electrical parameters thereof are measured to provide information on the charge density of the surface to determine the physical uniformity of the surface. Preferably a plurality of sensing electrodes are provided in a path extending along the surface in a direction generally cross-wise of the direction of relative movement between the surface and the sensing electrodes, and the detected current signals from the electrodes are scanned and then measured to obtain the aforesaid information. As a result, the size, number, and location of surface defects are readily determined.

Electrostatic pin hole detector

A photographic film is adapted to provide visual record of the occurrence of a transient electrostatic or transient magnetic field by the inclusion of metallic patterns close to the film. The patterns are of a geometry to define gaps at which the fields are concentrated in a manner to interact with the film. The film exhibits a light spot at the gap, when it is developed, if a field of sufficient intensity is present during the test period. The film packet is intended primarily for inclusion in the shipping package for sensitive electronic devices to provide a visual record of exposures during shipment.

Transient field indicator

A non contact voltmeter includes a multilayered structure adapted to configure a plurality of coupled capacitors in a manner to permit high speed operation. A high frequency input signal is applied to a plate capacitivity coupled to both the test object and a sensor. The structure is also configured to capacitivity couple the sensor directly to the test object. The structure allows for circuit configurations with low time constants permitting outputs at the input frequency as well as a small and inexpensive solid state configuration.

Non contacting volt meter

A hand-held, low cost, low voltage surface resistivity meter is provided by a contact surface which is essentially independent of the geometry of the surface to be measured. The use of special materials for the contact surface permits increased accuracy to be achieved at low voltages. Recognition that readings shown simply to the power of 10 are fully useful in characterizing a measured material permits a low cost, low voltage arrangement for the meter.

Surface resistivity meter

A dynamically balanced ion generator is provided which incorporates a detection screen and feedback loop to ensure that the number of positive and negative ions emitted from the generator are substantially equal. The detection screen is located between the ion generating electrodes and the exit port of the device, and is contructed of conductive material which captures a predetermined percentage of ions emitted by the electrodes. The detected imbalance is corrected through a feedback loop comprising an operational amplifier circuit, a low pass filter, a balance control comparator, variable duty cycle oscillator. By varying the duty cycle of the variable duty cycle oscillator, the voltage applied to the primary of a high voltage transformer is controlled such that the relative concentrations of positive and negative ions generated may be altered to compensate for any detected imbalance.

Dynamically balanced ionization blower

An improved electrostatic fluid filter is disclosed which is particularly useful in high performance clean rooms for the semiconductor industry. The electrostatic fluid filter is tubular in design and has an inlet port for supplying fluid (e.g., liquid, air) to be filtered and an output port from which relatively pure fluid flows. The filter includes a high voltage conductor which is disposed along the axis of the tube and which is surrounded by a ridged polytetrafluoroethylene insulator. Fluid is directed along the length of the filter parallel to the conductor. Contaminating particles in the fluid are transformed into electrical dipoles and are attached to the high voltage conductor.

Electrostatic filter

An improved electrostatic filter particularly for use in high performance clean rooms for the semiconductor industry is achieved by forming a layer of wires in a 'plane' having corrugations along an axis perpendicular to the axes of the wires. The 'plane' is designed to mate with the corrugations of a mechanical filter placed immediately upstream in the air flow path. Alternate wires of the layer are maintained electrically at opposite polarities to strengthen the fields and the corrugations permit closer movement of particles to the wires without unacceptable constriction of the air flow. A multilayered filter produces attractive field configurations, like those achieved by corrugated single plane filters herein, in the absence of a corrugated geometry.

The accuracy of measurements made to determine the extent of water vapor trapped upon encapsulation of an electronic device is significantly enhanced by carefully controlling the measurement technique employed. In particular, the encapsulant is generally punctured and the water vapor thus released is monitored. It has been found that to obtain an accurate measurement of the magnitude of the water vapor released, this measurement must be made within 0.1 second of the time of encapsulant punctured and released into a glass system. By using an absorption technique with suitable electronics, this time requirement is fulfilled and significantly more accurate quantitative measurements of entrapped water vapor are obtained.

Growing community of inventors

Langhorne, PA, United States of America

Peter R Bossard