Abstract: A semiconductor pressure sensor having a cylindrical housing with an opening formed at its tip end which is exposed to a pressure atmosphere and a metal diaphragm for receiving pressure, which is formed in a wall of the cylindrical housing defining the opening. A metal oxide layer is formed in a surface of the metal diaphragm by oxidizing the surface of the metal diaphragm, and a glass layer is formed on the metal oxide layer. A semiconductor chip, on which a strain gauge is formed, is firmly and surely bonded to the metal diaphragm through the glass layer by virtue of the metal oxide layer. This semiconductor pressure sensor can measure high pressure with sufficient sensitivity and high accuracy.

Abstract: A single transducer body having a sealing arrangement including both shoulder sealing surfaces and front end sealing surfaces to seal with mounting holes of component at offset shoulder or front end sealing surfaces.

Abstract: A transducer has a thick perimeter and an integral diaphragm extending across said perimeter, all formed of a thermoplastic resin. A thick mass is molded at the center of the diaphragm. Resistive elements formed of a conductive polymer are printed and baked on the diaphragm to form a Wheatstone bridge. The transducer is used as an accelerometer or load cell.

Abstract: A pressure sensor assembly includes two spacedly positioned flexible supports which support an elongated rod, with one end of the elongated rod contacting a pressure detector section on a disposable pumping cassette; the pressure sensor assembly can detect pressures in the cassette both above and below atmospheric (i.e., zero psig); when pressure changes in the cassette, the pressure detection section causes axial movement of the rod and the rod, in turn, flexes the two flexible supports. Position detection means associated with one of the two supports monitors the flexural movement of the one support, providing an indication of the pressure within the cassette.

Abstract: A pressure sensor utilizes the effect of different elastic moduli between layers or sections of different material that are bonded together to form a body, so that when the bonded material unit is subjected to a uniform hydrostatic external pressure, the differences in the elastic moduli of each of the materials will cause the materials to deflect in a predictable manner proportional to pressure. The amount of warpage or deflection of the body of material can be measured as a function of pressure. Specifically, two layers of materials, such as silicon and borosilicate glass, which have substantially different elastic moduli can be bonded across an interface surface to form an assembly, and when subjected to a substantially uniform pressure on the exterior surfaces the assembly will deflect for indicating applied pressure at relatively high pressure ranges.

Abstract: The present invention entails a force multiplying instrument that functions to multiply an input force, such as input pressure signal. A substantially constant area membrane is preshaped to assume a concave-convex shape and is disposed within a housing structure where it extends across an open chamber within the housing structure and is secured about its periphery by the side walls of the housing structure. For positive multiplication, a force sensing system is disposed on the concave side of the membrane and actually extends into engagement with the membrane for supporting the same about the concave side. Because the membrane is preshaped, it extends inwardly at a selected angle relative to the horizontal plan of the periphery of the membrane secured within the housing. The force applied to the convex side of the membrane and transferred against the force sensing system is multiplied because of the angle of the membrane and the position of the force sensing system.

Abstract: A method of assembling an electronic transducer having a dielectric casing member, a strain gauge, a metallic casing member including at least one wall in part defining an integral flexible diaphragm, and an electronic device including a plurality of solid state components. In this method, the strain gauge is bonded to the at least one wall spanning across the diaphragm so as to be at least in part conjointly flexible with the diaphragm. The electronic device is disposed in superposed spaced apart relation and in circuit relation with the strain gauge, and the strain gauge and the electronic device are enclosed between the dielectric casing member and the metallic casing member.

Abstract: In order to improve the stabilization and the heat-resistance of a strain gauge, the strain gauge is made of an amorphous alloy including Ni (nickel), Cr (Chromium) and Si (silicon). The amorphous alloy including Ni, Cr and Si has a high crystallization point, its temperature co-efficient of resistance is almost zero obtained by annealing. The amorphous alloy is stabilized from low to high temperatures and thus can be used from low to high temperatures without compensation. The amorphous alloy is a non-magnetic substance and the strain gauge thus is not substantially affected by external electromagnetic noise.

Abstract: A transducer for sensing fluid pressure including an enclosure forming housing, a cup-shaped rubber-like mount having an end wall and an annular side wall for supporting a pressure sensing electronic chip against the inner end wall surface of the mount. The chip is supported against the end wall in covering relation to a small opening in the end wall which connects one side of the chip with atmospheric pressure. A layer of non-hardening sealant gel extending between the inner side wall surface completely covers the chip and transmits fluid pressure to a second surface of the chip but inhibits fluid contact and leakage past the chip.

Abstract: A pressure transducer for in particular the measurement of relatively high pressures in the range of 10,000-50,000 psi and including an elongated frame having a capillary tube extending therethrough and employing a coupler at one end of the frame for sensing input pressure. A sensing member is provided disposed about the capillary tube at the other end of the frame and has, defined with the capillary tube, a sensing chamber in communication with the capillary tube. A recess is provided in the sensing member defining a relatively thin wall adjacent the annular sensing chamber. This wall has a pressure responsive sensing surface that extends substantially parallel to the capillary tube length and upon which strain gages are secured. A method is described for securing the capillary tube with the sensing member in a liquid tight manner.

Abstract: A pressure transducer has a thin central portion formed of a molded thermoplastic resin. A conductive polymer forms the resistive elements of a Wheatstone bridge printed and baked onto the molded substrate.

Abstract: A semiconductor pressure sensor having a cylindrical housing with an opening formed at its tip end which is exposed to a pressure atmosphere and a metal diaphragm for receiving pressure which is formed in a wall of the cylindrical housing defining the opening. A metal oxide layer is formed in a surface of the metal diaphragm by oxidizing the surface of the metal diaphragm, and a glass layer is formed on the metal oxide layer. A semiconductor chip, on which a strain gauge is formed, is firmly and surely bonded to the metal diaphragm through the glass layer by virtue of the metal oxide layer. This semiconductor pressure sensor can measure high pressure with sufficient sensitivity and high accuracy.

Abstract: Small pressure transducer able to operate in wide temperature and pressure ranges, as well as in aggressive environmental conditions, i.e. corrosive, radioactive or vibratory conditions. It essentially comprises a strip or blade (1) extended by two cylinders (13, 14), to which are fixed the ends of a bellows (10) within which a vacuum is produced. The cylinder (14) is offcentered or offset with respect to strip (1). The compressive stresses induce a pure bending and compression of the strip (1). Two extensometers of extensometric gauges (2,3) located on opposite faces of strip (1) and whereof the deformations are taken by an electric circuit make it possible to characterize the bending.

Abstract: A pressure transducer for the measurement of mid-range pressures in the preferred range of 500-7500 psi and including an elongated frame having a capillary tube extending therethrough and employing a coupler at one end of the frame for sensing input pressure. A sensing member is provided at the other end of the capillary tube and has a sensing chamber adapted to have at least one filler means disposed therein. A recess is provided in the sensing member defining a relatively thin wall adjacent the sensing chamber. This wall has a pressure responsive sensing surface that extends substantially parallel to the capillary tube length and upon which strain gages are secured.

Abstract: A pressure transducer for in particular the measurement of relatively high pressures in the range of 10,000-50,000 psi and including an elongated frame having a capillary tube extending therethrough and employing a coupler at one end of the frame for sensing input pressure. A sensing member is provided disposed about the capillary tube at the other end of the frame and has, defined with the capillary tube, a sensing chamber in communication with the capillary tube. A recess is provided in the sensing member defining a relatively thin wall adjacent the annular sensing chamber. This wall has a pressure responsive sensing surface that extends substantially parallel to the capillary tube length and upon which strain gages are secured. A method as described for securing the capillary tube with the sensing member in a liquid tight manner.

Abstract: In a mechanical electrical transducer strain-sensitive resistors (26, 27) are arranged on a strain member (7, 28, 38, 51, 53) in each case on sections (16-18; 32, 33; 45-48; 58-60) developed in transverse-beam fashion, which from the center of the strain member, are arranged tangentially to a circular arc extending concentrically to the center of the strain member. The transverse-beam sections are subjected on their surfaces substantially only to one-dimensional states of stress. The pairs of strain sensitive resistors are therefore stressed in a manner which does not simulate changes in pressure.

Abstract: An apparatus and method for measuring differential pressure of mud internal a drill string and mud in a borehole annulus is disclosed.

Abstract: Disclosed is an apparatus for pressure sensor compensation. The invention is best suited for pressure sensors of the type which may be mounted about a flexible member such that the resistance of one or more strain gauge resistors mounted thereon changes as pressure is exerted upon the flexible member. The pressure sensing apparatus comprises a bridge resistor arrangement for sensing pressure, and bridge control circuitry, coupled to an input terminal of the bridge, for compensating temperature induced variances in the bridge by controlling the voltage at the input terminal. The bridge has at least a first strain gauge resistor mounted on the flexible member, and at least one output terminal having a voltage which changes as pressure is exerted upon the flexible member. The bridge control circuitry has an additional strain gauge resistor which is used to monitor the temperature of the first strain gauge resistor.

Abstract: A proportional electro-hydraulic pressure control valve incorporates a pressure sensor in its valve body and the hydraulic fluid pressure in a pressure detecting fluid path provided in the valve body is delivered as an electric signal output by the pressure sensor. The pressure detecting fluid path is connected to a hydraulic fluid inlet port directly or through a restrictor or alternately the fluid path is connected to a pressure detecting port separated from both of the hydraulic fluid inlet port and a hydraulic fluid outlet port. The electric signal output from the pressure sensor is utilized to provide a numerical display of the controlled pressure or to effect the feedback control of a solenoid drive current through a closed loop.

Abstract: A pressure transducer is provided, in a preferred embodiment, with a pair of diaphragms (29, 28), each with a strain gauge, and with a rubber-like intermediate layer (33) therebetween. The layer (33) supports the first diaphragm (29) without interfering with its flexing up to a point where the layer (33) becomes non-resilient and transmits further flexing of the first diaphragm to the second diaphragm (28). The diameter of each diaphragm has to be about 2.75-3.75 times greater than that of its central flexing portion forming the bottom of a cavity (30) which, in the shown embodiment, is conical. The overall thickness of the diaphragm is preferably about 5 times greater than the thickness of the flexing portion to eliminate or at least substantially reduce the influence of parasitic stresses introduced by clamping forces holding the diaphragm in place.

Abstract: An ink jet printing device including a printing head having a nozzle through which ink can be ejected. The head includes an internal chamber ink and ink ejection is caused by internal pressure pulses. The internal chamber is formed in part by a deformable diaphragm which prevents extreme ambient temperature variations from causing damaging liquid pressure fluctuations.

Abstract: A pressure sensor converts a fluid pressure into electric signals upon displacement of a diaphragm. The pressure sensor includes a plurality of strain gauges which are formed on a moveable part of the diaphragm with terminal portions formed on a stationary part of the diaphragm. Readout wires are connected to the terminal portions of the strain gauges on the stationary part of the diaphragm.

Abstract: A pressure transducer (10; 10') having a silicon diaphragm (14; 14') and an insulating glass base (11; 11'). Surfaces (16, 12; 16', 12') of the diaphragm and glass base are anodically bonded together to form a hermetic seal for an internal reference cavity (24; 24') therein and also to provide hermetic protection for critical areas (70, 77; 70', 80, 81) on the silicon diaphragm. A plurality of semiconductor components are synthesized in an area (70; 70') in the silicon diaphragm. A plurality of conductors (71-73; 71'-73') are embedded (sealed) in the glass base so as to provide external electrical access to the semiconductor components without disrupting the hermetic seal provided between the silicon diaphragm and the glass base.

Abstract: A flat-spread force measuring apparatus comprising a stiff rigid main body having an essentially plane top surface for receiving a load; a plurality of flat cavities provided in said body spaced to each other and extending in parallel to said top surface; essentially bubble free elastomeric material contained in said cavities; a plurality of pressure sensors one each arranged in contact to said elastomeric material in each of said cavities; a plurality of force introduction members one each arranged in an essentially vertical alignment to said pressure sensors and below them; and evaluation means electrically connected to said pressure sensors for combining electrical signals received therefrom and representing local force components transmitted from said load receiving body through said elastomeric material to said pressure sensors.

Abstract: A catheter tip pressure transducer is employed for purposes of measuring fluid pressure within a living body. This includes a tubular housing having a pressure inlet aperture therein. A semiconductor block is carried within the housing and has first and second oppositely facing surfaces, one of which faces the inlet aperture and the other faces in the opposite direction. One of the surfaces has a recess formed therein of such a depth to define an elongated rectangular shaped membrane. A pair of elongated grooves are formed in the nonrecessed surface of the semiconductor block. These grooves are in registry with and straddle the longitudinal side edges of the membrane and define therebetween a raised longitudinally extending central portion in the form of a membrane beam which acts as a free beam supported at its opposite ends by the semiconductor block.

Abstract: A pressure transducer system which uses a Wheatstone bridge circuit to produce an electrical signal which is proportional to the amount of pressure exerted on it by gas or liquids, is disclosed. The Wheatstone bridge circuit is thermally isolated from the external environment using two diaphragms which are separated by a reservoir of silicone oil. This allows pressure to be hydraulically conveyed to the Wheatstone bridge circuit while preventing thermal contamination of the electrical signals produced by the Wheatstone bridge circuit. The pressure transducer also contains support circuitry which allows adjustment of the signals to and from the Wheatstone bridge circuit to enable the pressure transducer to be used with various electrical measuring equipment which has different operational ranges.

Abstract: A pressure transducer with a diaphragm coupler at one end and a sensing element at the other end connected by a capillary tube. The sensing element includes a cap member having a deformable surface including a top wall forming a thin diaphragm having a diametrically disposed raised beam extending across the top surface and having a gage received surface for receiving a plurality of strain gages. The deformable top wall surface has indentations therein on either side of and extending longtudinally of the raised beam to reduce tension forces across the diaphragm and improve linearity of the diaphragm.

Abstract: A pressure measuring element includes a plate-shaped substrate of ceramic material and a membrane deformable in response to pressure fluctuations. The membrane is made of ceramic material and is mounted to the upper side of the substrate. A pressure-sensitive resistor for measuring pressure is positioned inside the membrane. A heating resistor element is positioned on the underside of the substrate, which maintains the temperature of the substrate constant. A temperature sensor is also arrayed on the upper side of the substrate near the membrane.

Abstract: A coding circuit comprises an astable multivibrator which transforms the measurement of the variables in question, for instance pressure and temperature, into a time measurement. The astable multivibrator delivers a pulse signal whose pulse width is a function of the temperature and the cyclic ratio of which is a function of the pressure.

Abstract: A pressure transducer with a diaphragm coupler at one end and a sensing element at the other end connected by a capillary tube. The sensing element includes a cap member having a deformable surface including a top wall forming a thin diaphragm having a diametrically disposed raised beam extending across the top surface and having a gage receiving surface for receiving a plurality of strain gages.

Abstract: A pressure transducer for in particular the measurement of relatively high pressures in the range of 10,000-50,000 psi and including an elongated frame having a capillary tube extending therethrough and employing a coupler at one end of the frame for sensing input pressure. A sensing member is provided disposed about the capillary tube at the other end of the frame and has, defined with the capillary tube, a sensing chamber in communication with the capillary tube. A recess is provided in the sensing member defining a relatively thin wall adjacent the annular sensing chamber. This wall has a pressure responsive sensing surface that extends substantially parallel to the capillary tube length and upon which strain gages are secured.

Abstract: A pressure transducer for in particular the measurement of relatively high pressures in the range of 10,000-50,000 psi and including an elongated frame having a capillary tube extending therethrough and employing a coupler at one end of the frame for sensing input pressure. A sensing member is provided disposed about the capillary tube at the other end of the frame and has, defined with the capillary tube, a sensing chamber in communication with the capillary tube. A recess is provided in the sensing member defining a relatively thin wall adjacent the annular sensing chamber. This wall has a pressure responsive sensing surface that extends substantially parallel to the capillary tube length and upon which strain gages are secured. A method as described for securing the capillary tube with the sensing member in a liquid tight manner.

Abstract: A flange provided on a tubular metallic member coupled by glass bonding to the glass base to which the strain guage is fixed is made to contact with a receptacle step formed in a housing section of a housing, while pressurizing a metal ring in the housing section to cause plastic deformation of a part of the ring material into a coupling groove formed in the inner peripheral surface of the housing section, thereby coupling the metal ring and the housing.

Abstract: A monolithic accelerometer is fabricated with an integral cantilever beam sensing element which is etched out of a silicon wafer from the back surface. A thermal silicon oxide is formed on both surfaces of a (100) silicon wafer. Silicon oxide is removed from the back surface in a pattern which defines the sides of the cantilever beam and the sides of an alignment groove. The width and orientation of the openings in the silicon oxide are selected to control the depth of etching when the wafer is subsequently etched with an anisotropic etchant. An integrated circuit is then formed on the front surface and dry etching is used to complete the groove and separate the sides of the beam from the wafer.

Abstract: A strain gauge includes a flexible substrate and film of microfine grains of amorphous silicon connected between electrodes. A strain gauge assembly comprises a substrate, a first electrode formed on the substrate, a semiconductor body connected at a first end to the first wire and including a plurality of layers of different semiconductor materials forming a blocking diode and a resistance, and a second electrode connected to a second end of the semiconductor body such that the diode and resistance are between the first and second electrodes.

Abstract: A circular diaphragm with an annular thin portion has a smooth front surface, and coaxial but spaced inner and outer cylinders are secured to a rear surface of the diaphragm across said annular thin portion. Opposite edges of a rectangular strain member which is operatively connected to the disphragm through the inner cylinder are secured to a free end of the outer cylinder.

Abstract: An electrical strain gauge is provided in which the strain-responsive circuit element is formed from a thin film deposit on a surface of a metal substrate on which an insulating film has already been deposited. Connections are made directly to the circuit element by the ends of connecter leads that are bonded into insulating plugs in apertures in the substrate. The plugs and the insulating film are glasses to which the substrate and the circuit element are bonded. A further glass layer encapsulates the circuit element. As a result a very robust form of gauge is provided that can be used in high temperatures and in chemically active environments.

Abstract: A pressure transducer comprising an elongate hollow outer housing having a pressure sensor diaphragm and externally positioned fixing means which facilitates pressure tight introduction of the diaphragm into a pressure sensing port provided in apparatus capable of generating pressures to be sensed, two elongate members positioned within the outer housing in operative association with the diaphragm so as to move differentially in a direction parallel with the longitudinal axis of the housing consequent upon movement of the diaphragm responsively to a pressure to be sensed, and transducer means responsive to differential movement between the elongate members for producing a signal in dependence upon the pressure sensed.

Abstract: The present invention is a pressure sensing and measurement device that eliminates errors due to compliance and lack of sensitivity. The cell uses a pressure receiving means (such as a flexible diaphragm) to detect an impinging object, a means to counteract the pressure caused by the impinging object (such as internal hydraulic pressure), and a detector to measure the amount of internal pressure used to counteract the impinging force. Since the cell is internally pressurized to a point equal to a value equal to the external pressure, the diaphragm is undeflected and may avoid the problems inherent in simple diaphragm systems (such as bridging and insensitivity).

Abstract: A pressure gage particularly suitable in a variable temperature environment includes a body carrying two force rods. One of the force rods is coupled to the source of pressure to be measured while the second, of similar length and parallel to the first, is separated from the pressure to be measured. The total strain on both rods is affected by the same factors except that the rod coupled to the source of pressure is also affected by that source of pressure. When the strain of the two rods are subtracted the resultant strain is attributed only to the measured pressure.

Abstract: An apparatus for measuring fluid pressure has an electrical circuit for measuring fluid pressure which is closed only when simultaneously, the pressure to be measured is at least equal to a predetermined threshold and is substantially stable. A deformable member deforms under application of pressure of the fluid being measured and closes the electrical circuit. When fluid is moving through the apparatus, a Venturi valve member functions to lower the pressure of the fluid in contact with the deformable gauge member to reopen the electrical circuit. The Venturi valve member is formed by a revolution cone disposed in a chamber such that the passageway located annularly around the cone is reduced. A measuring apparatus integral with a deflating-inflating assembly is also provided.

Abstract: A differential pressure measuring transducer assembly of semiconductor material including a pressure receiving section producing a displacement when pressure is applied, and a stationary section of large thickness located at an outer periphery of the pressure receiving section. The pressure receiving section is composed of a large thickness portion extending to the stationary section at the outer periphery, and a small thickness portion occupying the rest of the pressure receiving section, and a gauge resistance is provided to the large thickness portion.

Abstract: A deflecting spring for distance or force measurement, particularly suited for use in force or pressure gauges and made of an areal spring material is provided with a force introducing section (2), a clamping section (6), and an intermediate section (45) connected to the first two sections (2,6) by flexural webs (10-13) which are equipped with sensor elements serving to convert bending into electrical signals. The intermediate section comprises two part sections (4,5) disposed at either side of an axis of symmetry (S) of the deflecting spring and each connected by a first web (10,11) with the force introducing section and by a second web (12,13) with the clamping section (6). By virtue of this design of the deflecting spring the respective webs belonging to a part section each are deflected in opposite directions when the force introducing section (3) is bended so that also opposite output signals are generated by the sensor elements.

Abstract: A system and method for measuring and controlling the parameters and conditions of a thin-wall submersed-tube fluid transport system called an "equiduct" system. The tube or tubes preferably are located near the bottom of a water artery such as a river, and are in fluid equilibrium with the surrounding water. This permits the tubes to have relatively thin, flexible walls, which makes the tubes relatively inexpensive and easy to install. Simple pumps cooperate with the slope of the river bed in pumping fluids through the tubes. Parameters such as fluid pressures and velocities, depth, gas and liquid concentrations, etc. are measured at spaced locations in the tubes, and the measurements are delivered to a central data processing and control station so that the parameters can be adjusted, or the need for repairs in the tubes can be detected and the repairs can be made.

Abstract: A transducer is provided for measuring very low pressures, on the order of 1.5 inches of water. A fluid-tight elastomeric barrier formed with convolutions to allow relatively large linear deflections is bonded to stiff sensing element of minimum mass, the deflection of which is sensed by strain gauges mounted on a neck connecting the sensing element to the transducer housing.

Abstract: An apparatus is disclosed for measuring the pressure of a fluid comprising a pressure sensing element and a pressure transmitting element. The pressure transmitting element has at least one inlet for receiving the fluid whose pressure is to be measured and a pressure transmitting wall member in fluid communication with the inlet, whereby the pressure transmitting wall member may be brought into contact with the pressure sensing element and a source of vacuum for drawing the pressure transmitting wall member against the pressure sensing element so that the pressure sensing element can substantially measure the absolute pressure of the fluid.

Abstract: A thin-film strain gauge and a method for producing it are proposed; the strain gauge is advantageously capable of integration into a thin-film circuit. The strain gauge comprises an elastically deformable spring element in combination with at least one elongation-sensitive resistor. The resistor disposition (R1-R4), the low-impedance connections (L11-L42) between the various resistance regions and the associated connection tracks (L5-L8) are applied in a vacuum process, preferably by cathode sputtering. The low-impedance connections (L11-L42) and the connection tracks (L5-L8) are of material which, although different from the material making up the actual resistance region, still has approximately the same temperature coefficient of resistance, so as to preclude errors caused by temperature.

Abstract: The apparatus for determining the pressure of capillary water in the ground, especially in soil, is of a two-part design and comprises a probe tube and a pressure measuring device. The pressure is measured by means of an elastically deformable membrane. For pneumatically coupling the pressure measuring device with the probe tube the latter is closed by a pierceable and self-sealing closure member. A hollow needle suitable for piercing the closure member is attached to the pressure measuring device. Either at or in the elastically deformable membrane there are arranged mechanical-electrical transducers which can be connected to an electric measuring and evaluation instrument for indicating the pressure which corresponds to the deformation of the membrane.

Abstract: A load cell, of the type that converts the magnitude of an applied load into an electrical signal, has a circuit board designed to facilitate wiring. The load cell includes a load cell body, strain gauges attached to the load cell body, and the circuit board which also is attached to the load cell body. The circuit board is composed of a flexible board, a wiring pattern formed on the flexible board, and soldering portions provided on the wiring pattern on either side of a bending portion at which the flexible board is bent for attachment to the load cell body. Symbol marks for identifying terminals are provided adjacent prescribed terminals of the wiring pattern formed on the circuit board.

Abstract: A high pressure transducer, especially for ballistic pressure measurements, with a body member and a sensor part, the body member can be screwed into a threaded mounting bore provided in a structural component, whereby the body member comes into sealing contact with its sealing surface against a seating surface of the mounting aperture. The body member is provided with a recess, into which projects an extension on the sensor part to be secured along its end-face on the body member. An annular gap is provided between the extension of the sensor part and the recess in the body member, which causes the force flux lines produced by the sealing forces not to pass through the sensor part so that the latter remains unaffected by changing conditions of the force flux lines, i.e. by the prevailing tightening torques.