Abstract: A micromechanical component, in particular a pressure sensor, including a substrate that has a membrane region, a surrounding region of the membrane region, at least one measuring resistance provided in the membrane region and modifiable by deformation of the membrane region, and a corresponding evaluation circuit provided in the surrounding region. An interference effect on the measuring resistance is producible by way of a deformation of parts, in particular conductor paths, of the evaluation circuit relative to the substrate. The invention also creates a corresponding equalization method on a test chip or as an individual final equalization.

Abstract: The active brazing solder for brazing ceramic parts of alumina, particularly of high-purity alumina, contains a maximum of 12 wt. % Ti, a maximum of 8 wt. % Be, and less than 16.5 wt. % Fe, the remainder being Zr and any impurities that may be present. The active brazing solder has the following behaviour/features: Brazing temperature: lower than 1,000° C.; the brazed joint is high-vacuum-tight over a long period of time; the coefficient of thermal expansion of the active brazing alloy is substantially identical to that of the alumina ceramic in the entire temperature range covered during the brazing process; the strength of the brazed joint between the two ceramic parts is so high that under tensile loading, fracture will result not at the joint, but in the adjacent ceramic; the pressure resistance of the active brazing solder is greater than 2 GPa; the active brazing solder is very good processable into powders having particle sizes on the order of 10 &mgr;m.

Abstract: A pressure sensor for a motor vehicle includes a sensor housing and a base. A pressure bore through the base leads to a pressure space delimited on one side by the base and on the opposite side by a diaphragm connected sealingly to the base. An actuating element is carried on a side of the diaphragm facing away from the pressure space. The actuating element actuates a sensor element in the sensor housing via a non-contact actuation. For protection against leakage due to a break in the diaphragm, a sealing cap surrounds the diaphragm and the actuating element and is sealingly connected to the base.

Abstract: A heat loss gauge for measuring gas pressure in an environment includes a resistive sensing element and a resistive compensating element. The resistive compensating element is in circuit with the sensing element and has temperature response and physical characteristics substantially matching those of the resistive sensing element and is exposed to a substantially matching environment. An electrical source is connected to the sensing element for applying current to heat the sensing element relative to the compensating element. Measuring circuitry is connected to the sensing element and the compensating element for determining gas pressure in the environment to which the sensing element and compensating element are exposed based on electrical response of the sensing element and the compensating element.

Abstract: A differential pressure sensor has a first and a second measuring chamber. Each measuring chamber is limited by a rigid carrier plate and a diaphragm plate, which is formed in the region of the measuring chamber as a pressure-sensitive measuring diaphragm. To design the differential pressure sensor to be resistant to overloading, the carrier plate is arranged between a first and a second diaphragm plate and has congruent concave depressions on opposite sides in the plane of the plate. The depressions are connected to one another by a central duct, penetrating the carrier plate perpendicularly to the plane of the plates. In the region of the measuring chambers, the diaphragm plates are formed congruently in relation to the depressions as pressure-sensitive measuring diaphragms. The measuring chambers are coupled to one another by a ram guided axially movably in the duct.

Abstract: The invention relates to a device for measuring pressure, temperature and flow velocity. It comprises a sensor (6) with a sensor support body (13) provided with a diaphragm (15) covering a cavity (14) formed in the support body (13). A pressure sensitive element (41) is mounted on the diaphragm, for recording pressure. Furthermore, a temperature sensitive resistor (42) mounted in the vicinity of and having known temperature dependences, for recording temperature. It also comprises an electrical circuit (43, 44, 45, 46) selectively outputting signals from either of the pressure sensitive element and the temperature sensitive resistor.

Abstract: A sensor operable at temperatures in excess of 400° C. is described. The sensor of the present invention operates without fluid fill, is non-porous, non-contaminating, and has no exterior exposed metallic components. The sensor includes a non-porous, impermeable sensing diaphragm that may be positioned in direct contact with fluids in an ultra-pure environment. The non-porous surface may be comprised of a layer of single crystal sapphire that is glassed to a backing plate. The sensor of the present invention is suitable for use in a chemically inert pressure transducer module for sensing pressures and/or temperatures in process fluids and may be molded directly into the high temperature plastic housing of the pressure transducer module.

Abstract: A pressure sensor includes a sensor element, and a resin package member that holds the sensor element. The sensor element is constructed by a semiconductor, and is capable of externally outputting an electric signal in accordance with strain generated when force is applied thereto. The sensor element is directly adhered to the package member via an adhesive layer that has Young's modulus in a range between 2.45×103 Pa and 2.06×104 Pa. Further the adhesive layer has a thickness equal to or more than 110 &mgr;m. Accordingly, the pressure sensor effectively restricts a variation in a sensor characteristic due to a thermal change.

Abstract: A differential pressure sensor has a first and a second measuring chamber. Each measuring chamber is limited by a rigid carrier plate and a diaphragm plate, which is formed in the region of the measuring chamber as a pressure-sensitive measuring diaphragm. To design the differential pressure sensor to be resistant to overloading, the carrier plate is arranged between a first and a second diaphragm plate and has congruent concave depressions on opposite sides in the plane of the plate. The depressions are connected to one another by a decentered duct, penetrating the carrier plate perpendicularly to the plane of the plates. In the region of the measuring chambers, the diaphragm plates are formed congruently in relation to the depressions as pressure-sensitive measuring diaphragms. The measuring chambers and the duct are filled with an incompressible fluid.

Abstract: A leadless sensor of the type employing a p+ rim which surrounds contact areas, each contact area defined by a metallized portion surrounded by a p+ semiconductor material, which p+ semiconductor materials or fingers are coupled to an active sensor array. The leadless sensor is bonded to a first glass cover member having two slotted apertures which communicate with the active regions of the sensor area on the underside and a top glass contact member which has two slotted regions which communicate with the piezoresistive sensors on the top side of the semiconductor wafer. The glass contact member has a series of corner through holes which are congruent with the contact terminals associated with the semiconductor sensor and which through holes are filled with a glass metal frit to enable contact to be made to the contact terminals of the semiconductor sensor.

Abstract: The present invention provides a differential-pressure transducer having two sensors cross-coupled and independently excited. A first Wheatstone Bridge pressure sensor has a first sensitivity and is excited by a first voltage. A second Wheatstone Bridge pressure sensor has a second sensitivity and is independently excited by a second voltage different from said first voltage. The excitation voltages are independently adjusted to increase or decrease the sensitivities of the sensors to substantially match. The outputs of the sensors are cross-coupled to each other to reduce the offset difference errors between the pressure sensors. Sensitive electronics are isolated within the sealed housing to protect them from harsh surrounding media. The transducer is configured to provide either a four pressure differential pressure measurement or a three pressure gauge differential pressure measurement.

Abstract: Two resistance elements (3, 6) are used for eliminating the influence of wall temperature on the gas pressure in a vessel, determined by a Pirani manometer. The first resistance element (3) is present in a first branch of a Wheatstone bridge (1), and the voltage is tapped by means of a voltage divider (7). The second resistance element (6) is present with a series resistance (5) in the second branch and is adjusted to a lower temperature. The changes in the voltages tapped at the branches are essentially identical for identical temperature changes at the resistance elements (3, 6), so that the Wheatstone bridge (1) remains balanced. The adjustment is improved by a constant current source (11).

Abstract: Support members are provided on the terminal portions of a sensor main body. In this state, a seal portion is formed by molding, and the seal portion seals the terminal portions of the sensor main body. During molding, external pressure acts on a housing. However, since four electrode wires pulled out from the housing are supported by insulating support members, the four electrode wires do not contact one another due to the pressure applied during molding, and thus do not short-circuit.

Abstract: The invention relates to a device for measuring pressure, temperature and/or flow velocity. It includes a sensor (6) with a sensor support body (13) provided with a diaphragm (15) covering a cavity (14) formed in the support body (13). A pressure sensitive element (41) is mounted on the diaphragm, for recording pressure. Furthermore, a temperature sensitive resistor (42) is mounted in the vicinity of the pressure sensitive resistor and has a known temperature dependence, for recording temperature. It also includes an electrical circuit (43, 44, 45, 46) selectively outputting signals from either of the pressure sensitive element and the temperature sensitive resistor.

Abstract: A pressure transducer including: a silicon substrate including: a first surface adapted for receiving a pressure applied thereto, an oppositely disposed second surface, and a flexing portion adapted to deflect when pressure is applied to the first surface; at least a first sensor formed on the second surface and adjacent to a center of the flexing portion, and adapted to measure the pressure applied to the first surface; at least a second gauge sensor formed on the second surface and adjacent to a periphery of the flexing portion, and adapted to measure the pressure applied to the first surface; a glass substrate secured to the second surface of the silicon wafer.

Abstract: Sensors for mounting in fluid chambers respond electrically to low pressures in the fluid, while resisting damage or leakage at high pressures. A flexible diaphragm, mounted at one end of a housing, is sandwiched between first and second annuli, leaving a center portion free to move in response to fluid pressure changes. The diaphragm moves a cylinder, which reciprocates in the second annulus against an adjustable spring bias. Travel of the cylinder away from the fluid is limited by a stop. Once the stop is reached, increased pressure on the diaphragm forces it against a fixed wall composed of a face of the second annulus and a face of the cylinder. The forces on the diaphragm are then all compressive. This enables the use of an easily flexed diaphragm for low pressure sensitivity, while resisting damage from high pressures. The moving cylinder is used to move a magnet that actuates a Hall effect switch, a Hall effect analog output transducer, or a reed switch.

Abstract: A fluid flow sensor uses lift forces exerted on a plate-like airfoil member to determine the velocity of a fluid flowing past the sensor. The member has a pair of spaced, low aspect ratio airfoil elements. A central portion of the airfoil member is coupled to a frame that positions the airfoil member in the fluid flow with an angle of attack with respect to the fluid flow direction. The flowing fluid generates velocity related lift forces on the airfoil member, the magnitude of which decrease along the airfoil member from the upstream end to the downstream end. The lift forces so applied deflect the upstream airfoil element to a greater extent than the downstream airfoil element. Strain gauges are coupled to the airfoil elements to detect their deflection. The strain gauges are connected in a bridge configuration to provide a signal indicative of fluid velocity.

Abstract: A pressure sensor has a movable diaphragm stretched directly between the annular pressing surfaces of two housing parts, and an electrical measuring device. In an area that is located radially outward as viewed from the pressing surfaces, the diaphragm has a sealing ring that abuts both housing parts. As a result, transverse vibrations of the diaphragm are reliably supported.

Abstract: A device for measuring various fluid pressures, the device includes a sensor plate which has fastening holes, which are distributed in matrixlike fashion over the sensor plate. Measuring diaphragms, which form end walls of blind bores in the sensor plate, are located between the fastening holes. Through fluid conduits of a hydraulic block to which the sensor plate can be secured, the measuring diaphragms can be acted upon by pressure. The evaluation is done with four strain gauges applied to each measuring diaphragm, the strain gauges being interconnected to form a Wheatstone bridge. Because it is possible to mount the sensor plate in a way that optimizes strain, it is possible to measure various pressures with minimal measurement error using one sensor plate.

Abstract: A sacrificial specimen for use in monitoring fatigue damage of a structural member including a main body made of the same material of the structural member and having an artificially formed crack at a central region thereof, and first and second thin epoxy resin plates cemented to both surfaces of the main body by an epoxy resin adhesive agent except for the central region. The main body is made by a thin metal plate having a thickness of 0.25 mm. In order to keep the central region of the main body free from the adhesive agent, a synthetic resin film is wound around the central region of the main body. The sacrificial specimen is secured to a surface of the structural member by means of an epoxy resin adhesive agent. A condition of fatigue crack growth at the artificially formed crack is monitored by a microscope, and fatigue crack of the structural member can be predicted from the monitored condition.

Abstract: The first glass substrate having the first pressure admitting entrance for leading the pressure of fluid to be measured, is arranged at a side of a diaphragm of a pressure sensor, for measuring differential pressure. The second glass substrate is arranged at the side opposite to the first glass substrate, a spacer being sandwiched therebetween. The second pressure admitting entrance is formed at the second glass substrate, at the position opposite to the first presser admitting entrance of the first glass substrate. The first conductive film and the second conductive film are formed on two surfaces facing to each other, of the first and second glass substrates, respectively. By measuring the specific conductance and the dielectric constant of the object fluid between the two conductive films, these physical constants indicating the quality of the fluid, the quality of the fluid can be also detected.

Abstract: A scanning circuit for an array of pressure responsive sensor points which permits the sensitivity of the circuit to be controlled. In particular, the sensitivity of the circuit may be controlled by controlling a test and/or reference voltage used with the circuit and different sensitivity or resolutions may be provided for different areas of the array. The circuit also provides enhanced interelectrode isolation, permitting a single test voltage to be utilized to scan all sensor points on a given input electrode and further reduces the time required to scan the array by reducing trace capacitance discharge time and by inhibiting processing for sensor points which are not of interest. The accuracy of pressures being sensed is also enhanced by adjusting the test voltage to compensate for load variations.

Abstract: A media-isolated differential pressure sensor apparatus and corresponding method combines a first signal (207, 209) provided by a first pressure sensor (101), indicative of a difference between a first pressure and second pressure applied across the first pressure sensor, and a second signal (213, 215) provided by a second pressure sensor, indicative of a difference between the second pressure and a third pressure applied across the second pressure sensor (103) to form a differential pressure sensor. Responsive to a pressure span the first signal (207, 209) responds with a slope response different than a slope response of the second signal (213, 215). A slope adjustment circuit (217) enables an adjustment of the slope response of the first signal (207, 209) to correspond to the slope response of the second signal (213, 215), and provides a slope adjusted first signal (221) dependent on the adjusted slope response.

Abstract: A sensor for use in a vortex flow meter which is capable of measuring various physical characteristics of a flow in a single process penetration from a common source. A shedder bar in the vortex meter generates alternating vortices. The sensor is located in the shedder bar within the stream of the fluid flow. The shedder bar serves as a composite vortex-generating plate and sensing unit. The shedder bar is structured such that it is either removable from the flow pipe for calibration, replacement, cleaning and the like or is permanently welded into the flow pipe with smooth or rigid contact surfaces. The sensor comprises one or more sensing diaphragms containing piezoresistor elements arranged in a Wheatstone bridge configuration. The sensor produces electric signals indicative of flow velocity, fluid pressure, and temperature. These signals are transmitted to a processing element which computes additional flow parameters.

Abstract: A sensor for use in a vortex flow meter capable of measuring various physical characteristics of a flow in a single process penetration from a common source. A shedder bar in the vortex meter generates alternating vortices. The sensor, which is fluidly connected to the vortex meter, comprises one or more pressure and temperature sensing diaphragms containing piezoresistor elements arranged in a Wheatstone bridge configuration. The sensor produces electric signals indicative of flow velocity, fluid pressure, and temperature. These signals are transmitted to a processing element which computes additional flow parameters.

Abstract: A single device acts as a pressure switch, gas generated heater, and an igniter. The device has pyrotechnic material such as a combustible gas in an inner chamber. An outer chamber, that is, a chamber in which the device is positioned, includes a gas that may or may not be combustible. A monitor current flows through a pressure monitor resistor and a bridgewire resistor monitoring continuity. When the pressure in the outer chamber decreases below a threshold value, the pressure monitor resistor breaks continuity and causes a resistance change. If an air bag is to deploy, the bridgewire resistor heats up to a point that the pyrotechnic material in the inner chamber is ignited. The resulting combustion ruptures pressure discs and the outward hot product heats the gas in the outer chamber. The outer chamber ruptures and the heated gas therein flows in the air bag.

Abstract: A pressure sensor is provided in which the pressure sensing components are isolated from a portion of an attached buffer member which is connected to a fluid conduit. The offset characteristic of the pressure sensor isolates stress from being transmitted between an attached external fluid conduit and the sensitive components of the pressure sensor. One embodiment of the pressure sensor solders a fluid conduit structure to a buffer member that is attached to a pressure sensor die. An alternative embodiment of the present invention avoids the need for making solder connections between the sensor structure and external components by utilizing elastomeric conductors and pressure seals in association with the pressure sensor composite structure and first and second housing structures. These elastomeric conductors also provide improved stress isolation. The housing structures are used to compress to the seal and the elastomeric conductor against selected portions of the composite sensor.

Abstract: A wet-to-wet pressure sensor package (10) having a housing (12) with a pressure sensitive semiconductor die (34) supported within a resilient mounting (44) including continuous beads (46, 48) of elastomeric adhesive on the same portion of the housing to provide a protective seal with less stress so that improved sensitivity and repeatability of the wet-to-wet pressure sensor is achieved.

Abstract: A liquid fluid level sensor responds to differential pressure forces exerted on a diaphragm as produced by exposure of liquid fluid to one side and of atmosphere to the other side. An arched resistance card is movable with the diaphragm to engage the mid-portion of a metal spring which progressively overlies greater portions of the card as the diaphragm moves thereby changing the resistance of a circuit including the card and the spring.

Abstract: An electronic control circuit for a bridge resistance circuit (10) of a transducer (20) has a switchable source of constant magnitude current (22) to direct current pulses of constant amplitude through the bridge circuit. A temperature setpoint detector (24) generates a temperature signal (TA) to a control logic circuit (26) when the circuit attains a predetermined temperature. The control logic circuit periodically turns on the current and directs a sample and hold network (32) to read the transducer output when the predetermined temperature is reached by enabling a gate (30). The control logic circuit turns off the current by applying a signal to the source of current after a reading of transducer output is taken. The current through the transducer develops its output, heats up the transducer and generates the temperature signal.

Abstract: A high density miniature sensor circuit useful for measuring pressure changes in a fluid in a closed chamber, comprising a high density of resistor segments gapped about 0.002 inches and conductors as contact pads which conductors are permanently affixed to a ceramic substrate is disclosed.

Abstract: Liquid differential pressure measurement apparatus using at each of two separate vertical locations a manifold with a pair of voids, each pair being covered with a thin, non-elastomer membrane pressing tightly against a horizontal fence line therebetween. A first void of each pair is gas pressurized from the external side of the manifold to move the membrane on the internal side of the manifold outwardly against the pressure head of liquid on the membrane at the location of the fence line, the gas escaping via the second void, which is vented. A meter connection to the first void of each pair is supplied to a differential pressure meter and/or a device that converts a differential pressure to an electrical signal for remote readout or the like.

Abstract: Device for conversion of a nonelectrical quantity into an electrical signal comprises measuring and compensating bridge circuits whose supply arms are connected to a power supply. A nonelectrical quantity like strain, force or pressure acts on the input of the measuring bridge circuit whose output is coupled to the input of a measuring circuit. The effect of destabilizing factors, such as temperature, electromagnetic field or aging of device components, is reduced by a suitable compensating bridge circuit whose output is connected to the input of a correction circuit. The measuring bridge circuit is one arm of the compensating bridge circuit. The correction circuit has differential outputs coupled to adjustable dividers whose number is equal to the number of compensating couplings introduced. Outputs of the dividers are connected to a displacement unit and to a device functional characteristic scaling circuit.

Abstract: A pressure measuring apparatus using process transmission media and comprising measuring and compensation systems. These systems have the substantially same construction which comprises a pressure receiving portion, a pressure transmitting portion and a pressure detecting portion. The pressure transmitting portion is divided into two sections, each of them contains a liquid NaK and a heat-resisting inert liquid, respectively, as pressure transmission media. A pressure of a fluid to be measured which is introduced into the pressure receiving portion of the measuring system is transmitted through the transmitting portion to the pressure detecting portion where the pressure is detected. A pressure of a gas introduced into the pressure receiving portion of the compensation system is detected in the pressure detecting portion of the compensation system in a same manner. The temperature compensation is conducted by subtracting a detected pressure in the compensation system from that in the measuring system.

Abstract: A liquid container is provided with paired variable resistors fluidly connected to the container at opposite ends of the bottom thereof. The resistors are electrically interconnected in series, and the output comprising the sum of the resistances is directly received by an electric current-responsive measuring device. Each of the resistors is weight-responsive and varies individually according to local liquid depth, however, the total resistance for a particular quantity of liquid in the container is always constant. The indicator of the present invention is particularly useful for measuring liquid content in containers subject to movement and change in attitude, such as, for example, gasoline tanks in motor vehicles.

Abstract: A liquid filled differential pressure transmitter includes a metallic measurement diaphragm within a pressure chamber and a pair of isolation diaphragms sealing the chamber from the process fluid which serve to transmit the applied pressure signals to the measurement diaphragm. The isolation diaphragms bottom against mating back-up surfaces to limit deflection of the diaphragm during overrange pressure conditions. An electrically conductive liquid fills the chamber so that measurable electrical resistances are established through the liquid between the measurement diaphragm and a pair of electrodes adjacent thereto formed on opposite walls of the chamber. As the measurement diaphragm deflects in response to applied pressure signals, the electrical resistance between the diaphragm and each of the electrodes changes providing an output signal which is a function of the applied differential pressure.

Abstract: Disclosed herein is a multiple function pressure sensor for use in combination with an electronic fuel injection system for an internal combustion engine. The preferred embodiment has two pressure sensitive elements in a single housing which generate signals indicative of the absolute pressure in the engine's intake manifold and the absolute value of the ambient or atmospheric pressure. Included electronic circuitry subtracts the value of the engine's manifold pressure from the value of the atmospheric pressure and generates a third pressure signal indicative of the difference between the manifold pressure and atmospheric pressure. These three pressure signals are utilized in the electronic fuel injection system for computing the fuel requirements of the engine under various operating conditions.

Abstract: A pressure transducer of miniature design with a silicon diaphragm which is provided with a monolithic resistor arrangement, the resistance of which changes with the deformation of the diaphragm in which the diaphragm is arranged between two overload bodies, one of which rests on a support body, whose surfaces facing the diaphragm are each provided with a pressure chamber and pressure canals to obtain an overload-proof pressure transducer which is very small and can be used for measuring large pressure differences.

Abstract: .Badd.A pressure responsive device comprising a bridge pattern film bonded to the surface of an electrically non-conductive diaphragm. The bridge including active segment means near the center of the diaphragm in the region thereof where the distance radius ratio is less than about 0.6 and active segment means in the region of the diaphragm where the distance/radius ratio is at least about 0.7..Baddend.