摘要:
A piezoresistive sensor device and a method for making a piezoresistive device are disclosed. The sensor device comprises a silicon wafer having piezoresistive elements and contacts in electrical communication with the elements. The sensor device further comprises a contact glass coupled to the silicon wafer and having apertures aligned with the contacts. The sensor device also comprises a non-conductive frit for mounting the contact glass to a header glass, and a conductive non-lead glass frit disposed in the apertures and in electrical communication with the contacts. The method for making a piezoresistive sensor device, comprises bonding a contact glass to a silicon wafer such that apertures in the glass line up with contacts on the wafer, and filling the apertures with a non-lead glass frit such that the frit is in electrical communication with the contacts. The use of a lead free glass frit prevents catastrophic failure of the piezoresistive sensor and associated transducer in ultra high temperature applications.
摘要:
A pressure transducer has an H-shaped cross-sectional header having a front and a back section. The front and back sections are of equal diameter and are circular. Each front and back section has a depression with an isolation diaphragm covering the depression. Each diaphragm is of equal size and the depressions communicate one with the other via a central channel in the central arm of the H. A pressure sensor communicates with the channel, where the pressure sensor responds to a first pressure applied to the first isolation diaphragm and a second pressure applied to the second isolation diaphragm. The pressure sensor produces an output equal to the difference in pressure. The differential pressure transducer having both diaphragms of the same size and still enabling leads from the sensor to be brought out.
摘要:
A pressure transducer has an H-shaped header having a front and a back section. The front and back sections are of equal diameter and are circular. Each front and back section has a depression with a diaphragm covering the depression. Each diaphragm is of equal size and the depressions communicate one with the other via a central channel in the central arm of the H. A pressure sensor communicates with the channel, where the pressure sensor responds to a first pressure applied to the first diaphragm and a second pressure applied to the second diaphragm. The pressure sensor produces an output equal to the difference in pressure. The differential pressure inducer having both diaphragms of the same size and still enabling leads from the sensor to be brought out.
摘要:
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.
摘要:
A pressure probe includes a longitudinal tubular housing symmetrically disposed about a central axis and having an ultra miniature conical front end and an opened back end. A plurality of aperture ports having an opening are disposed about the front end. A plurality of ultra small leadless transducers has a central active deflecting area in a semiconductor substrate, and a layer of oxide on a bottom surface. At least one sensor network is disposed within the active area on the oxide layer. A glass contact wafer is bonded to the non-deflecting portion of sensing network and has a number of apertures surrounding the active area suitable for interconnection with header. A header encloses each transducer and is of a shape and size to be positioned in an associated aperture port of the probe housing. At least one lead is coupled to a header pin extending from bottom of the aperture and directed through the bottom opening into the hollow of the probe housing.
摘要:
A transducer sensor is positioned within a hollow of the body of a housing. The housing has an extending alignment pin, which pin coacts with a corresponding slot or aperture in the wall of a vessel whose pressure or temperature is to be monitored. The transducer body is associated with a connector where the alignment pin is placed and extends from the housing in a fixed relation to the connector. A suitable aperture or slot in the wall of the vessel to be monitored accommodates the extending pin whereby when the transducer is placed in the vessel aperture the connector associated with the transducer is always located in proper position. Positioned on the housing is a sliding nut which can move in a direction parallel to the central axis of the housing and either to the right or left. This sliding nut is rotatably positioned in the housing and coacts with threads formed in the aperture in the wall of the vessel to enable tightening of the transducer housing when placed in the wall and when the alignment pin is positioned within the corresponding slot or aperture. This assures a proper alignment so that an external connector which is not moveable or rotatable can be immediately connected to the transducer connector without further experimentation or adjustment.
摘要:
A high temperature pressure sensing system (transducer) including: a pressure sensing piezoresistive sensor formed by a silicon-on-insulator (SOI) process; a SOI amplifier circuit operatively coupled to the piezoresistive sensor; a SOI gain controller circuit including a plurality of resistances that when selectively coupled to the amplifier adjust a gain of the amplifier; a plurality of off-chip contacts corresponding to the resistances, respectively, for electrically activating the corresponding resistances and using a metallization layer for the SOI sensor and SOI ASIC suitable for high temperature interconnections (bonding); wherein the piezoresistive sensor, amplifier circuit and gain control circuit are suitable for use in environments having a temperature greater than 175 degrees C. and reaching between 250° C. and 300° C., and wherein the entire transducer has a high immunity to nuclear radiation.
摘要:
A system for providing for tactile feedback to a physician or other user employs a robotic control system, which robotic control system enables the user to control an operating instrument such as a scalpel or other instrument. Pressure transducers are placed upon the instrument and the outputs from the transducers are directed to a microprocessor and glove control circuit. The microprocessor receives the signals from the pressure transducer and the signals from the robotic control system to produce output signals for controlling a glove. The glove is worn by the physician during a robotic operation. The glove contains means on the inside of the glove, which means receive the signals generated by the microprocessor and glove control circuit and provides tactile feedback to the hand of the physician or Other user while wearing the glove. This tactile feedback provides indications to the user of the robotic control signal system as to the pressure or force applied by the surgical instrument during the robotic operation. There is also described a technique for training a physician to use this system. The system employs inflatable air sacks positioned on the inner surface of the glove but other tactile indications such as heat can be employed.
摘要:
A leak detector apparatus for a pressurized cylinder having a cylinder of a radius (r) with a slidable piston in the cylinder with a gas filled chamber positioned between a cylinder end and the piston face. The length (L) of the chamber is calculated according to load changes on the piston where the volume (Vc) of the chamber changes. The pressure and temperature of the chamber are measured as well as the length. These values are inputted to a processor to solve the ideal gas law equation PV=nRT where a change in n for a change in length indicates a leak.
摘要:
An ultra high temperature hermetically protected transducer includes a sensor chip having an active area upon which is deposited piezoresistive sensing elements. The elements are located on the top surface of the silicon wafer chip and have leads and terminals extending from the active area of the chip. The active area is surrounded with an extending rim or frame. The active area is coated with an oxide layer which passivates the piezoresistive sensing network. The chip is then attached to a glass pedestal, which is larger in size than the sensor chip. The glass pedestal has a through hole or aperture at each corner. The entire composite structure is then mounted onto a high temperature header with the metallized regions of the header being exposed to the holes in the glass pedestal; a high temperature lead is then bonded directly to the metallized contact area of the sensor chip at one end. The leads are of sufficient length to extend into the through holes in the glass pedestal. A sealing cover is then attached to the entire composite sensor to hermetically seal all of the interconnections. The sealing cover is a glass structure, has a central aperture which corresponds to the aperture formed by the frame, allowing the active area of the sensor to be exposed to the pressure medium. The sealing cover is bonded to the periphery of the rim and to the glass supporting pedestal.