Abstract:
There is disclosed a high pressure sensing header which is relatively insensitive to mounting torque. The header comprises an outer torque isolating shell which surround an inner “H” section header. The inner “H” section header has a thick diaphragm and is surrounded by the torque isolating shell which is secured to the “H” section header at a peripheral flange of the “H” section header. In this manner when the header is installed, the installation force is absorbed by the outer shell and there is no installation force or torque exhibited by the inner “H” section which will respond only to stress due to pressure. The torque isolating shell also contains a top surface which has a counterbore that accommodates a crush ring. When the unit is installed, the crush ring is crushed against an installation wall to enable the inner header to receive pressure without experiencing significant installation force.
Abstract:
There is disclosed a flat planar pressure transducer which comprises a planar insulative substrate of a rectangular configuration. Disposed on the substrate is an array of conductive areas which extend from a contact terminal area of said substrate to an end of the substrate. There is a leadless sensor module positioned at said contact terminal area, with the contacts of said leadless sensor contacting contact terminals of said contact terminal area. The leadless sensor is enclosed by an enclosure which is coupled to the substrate and surrounds the sensor. The enclosure has a screen positioned on the top surface to prevent particles from entering or damaging the leadless sensor. The above-noted structure forms a very flat, compact pressure transducer which can be utilized in lieu of flex circuit type devices and provides greater mechanical stability as well as a more accurate output.
Abstract:
There is disclosed a high pressure sensing header which is relatively insensitive to mounting torque. The header generally includes an outer torque isolating shell which has a “C” shaped cross section with the cylindrical shell surrounding an inner “H” section header. The inner “H” section header has a thick diaphragm and is at least partially surrounded by the torque isolating shell. In this manner, when the header is installed, the installation force is absorbed by the outer shell and there is relatively no installation force or torque exhibited by the inner “H” section which will respond only to stress due to pressure.
Abstract:
A filter assembly for use with a static-dynamic piezoresistive pressure transducer that measures low amplitude, dynamic pressure perturbations superimposed on top of a high static pressure through the implementation of a low-pass mechanical filter assembly is disclosed. The filter assembly may comprise a dual lumen reference tube and a removable filter subassembly further comprising a porous metal filter and narrow diameter tube. The transducer, which may be capable of operating at ultra-high temperatures and in harsh environments, may comprise of a static piezoresistive pressure sensor, which measures the large pressures on the order of 200 psi and greater, and an ultrasensitive, dynamic piezoresistive pressure sensor which may capture small, high frequency pressure oscillations on the order of a few psi or less. The filter assembly may transmit static pressure to the back of the dynamic pressure sensor to cancel out the static pressure present at the front of the sensor while keeping dynamic pressure from reaching the back of the sensor. In this manner, the filter assembly enables the transducer to accurately read dynamic pressure in the presence of high static pressure without rupturing the thin diaphragm of the dynamic pressure sensor.
Abstract:
A dual diaphragm pressure transducer, or sensor, with compensation for non-pressure effects is disclosed. The pressure sensor can include two pressure transducers located on separate portions of a chip. The first pressure transducer can be a differential pressure transducer, which produces a signal proportional to one or more applied pressures and includes other non-pressure effects. The second pressure transducer can be sealed in a hermetic chamber and thus can produce a signal proportional only to non-pressure effects. The signals can be combined to produce a signal proportional to the applied pressures with no non-pressure effects. The first and second pressure transducers can be physically and/or electrically isolated to improve sealing between the two pressure transducers and prevent pressure leaks therebetween.
Abstract:
There is disclosed a mounting technique for mounting a semiconductor chip of the leadless or so-called flip chip type to a header. The header has an insert made of glass or other suitable non-conductive material within the header hollow. Mounted into the glass insert are a series of conductive metal pins which are placed in areas so that when a chip is mounted in the header, the chip makes contact with these conductive pins and allows one to make outside connections. Also positioned in the header are a series of nonconductive guide pins. These pins are placed in suitable positions in the header to enable one to contact the outside surfaces of the chip when the chip is placed in the header. In this manner, the chip is constrained from movement from side to side or from rotation. However, due to the positioning of the nonconductive pins within the header, it is possible to move the chip up and down while mounting.
Abstract:
Disclosed herein is an electronic switch that comprises a pressure sensitive bridge array adapted to monitor pressure and activate an indicator when the monitored pressure exceeds a predetermined value indicative of a dangerous condition. The electronic switch further comprises a monitoring circuit adapted to test the overall operability of the pressure sensitive bridge array and its accompanying electronics control circuitry.
Abstract:
A filter assembly for use with a static-dynamic piezoresistive pressure transducer that measures low amplitude, dynamic pressure perturbations superimposed on top of a high static pressure through the implementation of a low-pass mechanical filter assembly is disclosed. The filter assembly may comprise a dual lumen reference tube and a removable filter subassembly further comprising a porous metal filter and narrow diameter tube. The transducer, which may be capable of operating at ultra-high temperatures and in harsh environments, may comprise of a static piezoresistive pressure sensor, which measures the large pressures on the order of 200 psi and greater, and an ultrasensitive, dynamic piezoresistive pressure sensor which may capture small, high frequency pressure oscillations on the order of a few psi or less. The filter assembly may transmit static pressure to the back of the dynamic pressure sensor to cancel out the static pressure present at the front of the sensor while keeping dynamic pressure from reaching the back of the sensor. In this manner, the filter assembly enables the transducer to accurately read dynamic pressure in the presence of high static pressure without rupturing the thin diaphragm of the dynamic pressure sensor.
Abstract:
A system for sensing at least one physical characteristic associated with an engine including a turbine having a plurality of blades turning inside a casing, the system including: a pressure sensor coupled substantially adjacent to the casing and including at least one output; a port in the turbine casing for communicating a pressure indicative of a clearance between the blades and casing to the pressure sensor; a cooling cavity substantially surrounding the pressure sensor; and, an inlet for receiving fluid from the engine and feeding the fluid to the cooling cavity to cool the pressure sensor; wherein, the pressure sensor output is indicative of the clearance between the blades and casing.
Abstract:
There is disclosed flat planar pressure transducer which comprises a planar insulative substrate of a rectangular configuration. Disposed on the substrate is an array of conductive areas which extend from a contact terminal area of said substrate to an end of the substrate. There is a leadless sensor module positioned at said contact terminal area, with the contacts of said leadless sensor contacting contact terminals of said contact terminal area. The leadless sensor is enclosed by an enclosure which is coupled to the substrate and surrounds the sensor. The enclosure has a screen positioned on the top surface to prevent particles from entering or damaging the leadless sensor. The above-noted structure forms a very flat, compact pressure transducer which can be utilized in lieu of flex circuit type devices and provides greater mechanical stability as well as a more accurate output.