Alliedsignal Inc.

Honeywell G.m.b.h.

Beckman Instruments, Inc.

Other

Anthony J Bernot

Liang A Xue

Kenneth Brown

Grenville Hughes

Laura J Lindberg

Louis D Silverstein

Michael J Johnson

Daniel R Danowski

William H McCormack

Richard M Sturgeon

Phillip J Woodall

Pingyu Liu

Karl H Blomgren

Nicholas F Schmidt

Raymond H Niska

A dry pressing and slip casting process is provided for the manufacture of glass-ceramic components of the type used in sensors. Both process on starts with a powder composition of SiO (42-59 wt. %), Al O (17-35 wt. %), MgO (2-25 wt. %) and also BaO (0-20 wt. %), TiO (0-12 wt. %), ZnO (0-10 wt. %), CaO (0-10 wt. %), B O (0-5 wt %), P O (0-5 wt. %), ZrO (0-5 wt. %), alkali oxides such as K O, Na O (0-3 wt. %) and other small amounts (0-1 wt. %) of additives such as Fe O , As O . Fe O , V O , As O . Some of the ingredients (e.g. Mg, Ba, Ca) can also be present in the form of fluoride, e.g., MgF , BaF , CaF , to up to 10 wt. %. Additional ceramic additives up to 30 wt. %, which are as second phase (e.g., Al O , Y O doped ZrO , SiO , mullite, zircon, carbides, nitrides, and a combination of the above), are not part of the glass composition, but are introduced to enhance both the mechanical strength and toughness and to further modify the coefficient of thermal expansion. In the dry pressing process the powder is milled, blended with a binder and then subjected to a drying/granulation process. A die cavity of a desired shape is then filled with the powder. Pressure is then applied to die for a period of time. After the pressure is removed, the green ceramic part is ejected and then sintered to become a finished ceramic cover or header. In the slip casting process, the powder is milled and dispersed in a water. The slip is then poured or pumped into a permeable casting mold of a desired shape made of Gypsum. When either the liquid has been completely sucked away by the mold or the desired depositing thickness has been reached, the cast green ceramic part is removed from the mold, dried and then sintered into a finished ceramic cover or header.

Glass-ceramic pressure sensor support base and its fabrication

A capacitive pressure sensor capsule having a support base with a cavity is provided. The capsule includes a housing having a ceramic cover sealingly attached to a ceramic base to define an interior chamber. The base has a cavity facing this interior chamber and at least one hole adjacent the cavity that extends through the base. A glass sensor has a first diaphragm with a first electrode and a second diaphragm with a second electrode bonded together to form a capacitor and is mounted in the chamber so that one of the diaphragms is received within the cavity and the other diaphragm lies on the surface of the base and covers the hole. A conducting member extends from the sensor, through the hole to electronic circuitry mounted to the capsule. The cavity also has a land for supporting the diaphragm disposed therein.

Pressure sensor support base with cavity

A capacitive pressure sensor capsule has a housing with a ceramic cover sealingly attached to a ceramic base that defines an interior chamber. The sensing medium enters the chamber through an inlet port. A glass sensor is attached to an integral pillar that extends from the housing into the chamber. A conducting member extends through the pillar into the housing and carries the signals from the sensor. The combination of the glass sensor and ceramic housing provides high accuracy over a wide range of temperature, because the thermal coefficient of expansion of glass and ceramic are similar. Hermetic sealing of the sensor electrical circuitry ensures long term immunity from the sensed environment.

Capacitive pressure sensor housing having a ceramic base

The present provides a method for making glass pressure sensors in batch. First glass plates of appropriate dimensions are scribed. Then electrodes are sputters onto each of the plates, followed by screen printing a frit layer and crossover tabs. The plates are then preglazed and bonded together to form a plurality of sensors. The plates are then scribed and broken along the scribes to form individual sensors.

Method for making glass pressure capacitance transducers in batch

The capacitance type pressure transducer is disclosed which includes an isolation additional diaphragm made of the same material as the operative diaphragms the transducer. Material may be quartz, silicon, or aluminosilicate. The isolation diaphragm minimizes deflections of the operative diaphragms as the housing base is bowed due to the pressure differential between the internal reference pressure of the capsule and the ambient pressure. The transducer may be configured to measure an absolute pressure or a differential pressure.

Compensated pressure transducer

A vehicle anti-theft system in the form of a mechanically interengagable electronic key and lock includes stored key and vehicle identifiers in both the key and in the lock. A random number is generated in the lock each time the vehicle ignition switch is closed and that random number is used to encode one of the identifiers for transmission to the key. The key uses the corresponding stored identifier to recover the random number. The other stored identifier is then encoded using the recovered random number and the encoded other identifier is returned to the lock. The lock uses the generated random number to recover the second identifier for comparison to its stored value. If the comparison fails, vehicle operation is prevented. The system may effect several trials, each using a new random number before refusing further attempts. The lock electronics is preferably disposed in the vehicle fuel tank and controls operation of the vehicle fuel pump.

Cryptographically secure electric fuel pump system

A capacitive pressure transducer is made of aluminosilicate glass or any other glass having a low thermal coefficient.

Aluminosilicate glass pressure transducer

An electronic color filter system for controlling a picture element color signal includes three filter regions which selectively control spectral components of light transmitted sequentially therethrough. Each filter region has a liquid crystal host material and a dye guest component. The orientation of the liquid crystal host, determined by an electric field applied to the filter material, determines the absorption coefficient of the dye guest component to polarized light. By appropriate selection of the guest dye component and control of the electric fields applied to the host liquid crystal, the transmitted light can have a selected radiation spectrum. The transmitted light of a multiplicity of picture elements can be used to provide a full-color visual image display.

Apparatus and method for an electronically controlled color filter for

A liquid crystal display is described that includes gray scale capability. Each pixel of the display is subdivided into a plurality of subpixels. Each subpixel includes an effective capacitor, with the liquid crystal material contained between the effective capacitor plates, and includes a control capacitor coupled in series with the effective capacitor. By controlling the capacitance of the control capacitors of the subpixels, selected subpixels can be activated as a function of the voltage applied across the series capacitors. By controlling the number of subpixels that are activated by the applied voltage, a gray scale capability can be provided for a liquid crystal display.

Apparatus and method for providing a gray scale capability in a liquid

A process for generating high resolution conductive patterns on an insulating substrate. A photosensitive resin coating applied to the surface of a substrate is exposed to a suitable light source through a mask. The unexposed portion of the coating defines the desired conductive pattern which is then coated with a low temperature melting glass powder. The substrate is fired to sinter the glass pattern and fuse it to the substrate. The substrate is then coated with a slurry of fine metal particles suspended in a volatilizable carrier. The substrate is again fired to sinter the metal into a united mass and causing it to fuse only with the low temperature melting glass pattern. The unadhered portions of the metal coating are removed by a washing operation. An exclusively metallic layer is thereby formed on a high resolution glass pattern intermediate layer supported by the substrate.

Process for generating conductive patterns

A method of constructing a gas discharge display device in such a manner that contaminants found within the completed display are significantly reduced. The process for assembly of the display incorporates the utilization of a spacer member having a higher melting temperature than the display's perimeter seal and is designed to hold the plates apart without letting certain portions of the sealing material contact the opposing substrate. The use of the spacer member of high temperature material permits a higher temperature to be achieved in the vacuum furnace for evacuating the contaminants produced by out-gassing of impurities in the dielectric and conductive materials as well as the glass substrates and the sealing material. The sealing time for the display after evacuation is shortened to prevent or greatly reduce the possible entrapment of impurities in the display during the higher temperature final sealing step.

Growing community of inventors

Gilbert, AZ, United States of America

Anthony J Bernot