Abstract: A differential pressure transmitter detects a differential pressure condition of a fluid by means of a semiconductor sensor. First and second seal diaphragms are provided in a member which constitutes the differential pressure transmitter, to form first and second pressure receiving chambers. An overload protection diaphragm and first and second damper chambers are provided at positions close to the first and second pressure receiving chambers. Also, there are provided a passage for connecting the first pressure receiving chamber and the first damper chamber, a passage for connecting the second pressure receiving chamber and the second damper chamber, and passages for connecting the first and second damper chambers respectively with the semiconductor sensor. Even when a change is caused in the temperature of a processed fluid to be detected, the differential pressure transmitter quickly detects the temperature change, so that a differential pressure of the processed fluid can be measured with high accuracy.

Abstract: A transmitter provides an output indicative of pressure of process fluid. The transmitter has a first body with a passageway filled with isolation fluid extending from a first port to a pressure sensor. A second body has an inlet for receiving process fluid and a second port. An isolation diaphragm between the first and second ports isolates process fluid from isolation fluid. A seal adjacent the diaphragm seals the diaphragm and couples the diaphragm to the second body. A spring urges the seal against the diaphragm.

Abstract: A modular pressure sensor has a pressure-sensing element, electrical terminals, interconnections, and a support substrate. The pressure-sensing element produces an electrical signal indicative of pressure at local contacts and the interconnections apply the signal to the electrical terminals. The electrical terminals are secured to the substrate and extend along a peripheral surface of the substrate. The modular pressure sensor can mount, with different orientations, to a header to form a pressure transducer.

Abstract: A pressure sensor (20) comprises a deformable diaphragm (22) which closes a fluid passage (18) in sealed manner. In order to protect the diaphragm (22) from shocks, the passage includes a restriction (44) whose dimensions are so designed as to limit the pressure peak applied to the diaphragm to a cutoff value which the diaphragm can withstand. The restriction (44) may be formed in a detachable capillary tube (42) or it may be in the form of grooves in a small silicon plate integrated in the active portion of the sensor.

Abstract: An isolator diaphragm is formed and connected to a support member so it will withstand periodic high pressure cleaning. Such periodic cleaning includes use of heated, concentrated cleaning solutions flowing under high pressure from a nozzle which moves rapidly over segments of an exposed surface of the isolator diaphragm. The present invention prevents isolator diaphragm failure precipitated by the substantially incompressible isolator fluid driven toward the perimeter of the diaphragm during cleaning operations. Such cleaning operations generate a separating force between the isolator diaphragm and diaphragm support. The isolator diaphragm has a peripheral wall portion bonded to a planar support surface and is formed to have an offset center region. The peripheral wall and center region are joined by a conical, inclined wall bounding the center portion. The support member has a correspondingly shaped recess with an inclined annular wall that supports the conical wall of the diaphragm.

Abstract: An active integrated circuit transponder with on-board power supply is mounted in or on a vehicle tire. A pressure sensor, a temperature sensor and a tire rotation sensor are mounted on a substrate along with the integrated circuit transponder chip, the power supply and an antenna. Upon receiving an interrogation signal from a remote source, the transponder activates the sensors to sense tire pressure and temperature and transmits an encoded radio frequency signal to the remote source containing serial, encoded tire identification, tire position on the vehicle, current tire pressure, current tire temperature and accumulated tire revolutions, as well as maximum and/or minimum tire and temperature pressure values encountered over a predetermined time period and other information specific to the tire.

Abstract: A pressure sensor die is provided with a flexible membrane and a plunger which combine to amplify a low pressure signal while also providing media isolation between a fluid being measured and the internal components of a pressure sensor. One embodiment of the pressure sensor disposes an end of the plunger in direct contact with a pressure sensor die while another embodiment disposes an elastomeric diaphragm between the plunger and the pressure sensor die. This second embodiment creates a chamber between the plunger and the pressure sensor die in which a fluid is captured by movement of the plunger. The captured fluid is decreased in volume by movement of the plunger and the resulting increase in pressure in transmitted to a pressure sensitive portion of a pressure sensor die. The device is particularly useful in conjunction with applications where media isolation is required between the fluid being measured and the components of the pressure sensor, such as kidney dialysis machines.

Abstract: An electronic pressure sensor (10) is enhanced by attaching a sensor die (18) to a stress isolation platform (12) using an adhesive (42) having a similar thermal coefficient of expansion. The adhesive provides a hermetic seal between the stress isolation platform and the pressure sensor die. A via (20) in the stress isolation platform provides an opening for pressure to be applied to the sensor die. The stress isolation platform is attached to a plastic package body (16) via a semi-rigid adhesive (40) for providing stress isolation and a hermetic seal between the package body and the stress isolation platform. Any hostile chemical entering the via contacts an exposed diaphragm (50) of the sensor die to assert pressure against its piezoelectric network (52) to generate the electrical signals representative of the applied pressure but are kept away from the sensitive interconnects by the hermetic seals.

Abstract: A pressure transducer is provided for measuring pressure within a measurand environment, the transducer comprising a header which includes a substantially nondeformable molded housing formed from a first thermoplastic material defining a cavity and first and second openings into the cavity and a resilient diaphragm formed from the first thermoplastic material molded to the housing and spanning the first opening; a pressure sensing device disposed within the housing; and a pressure transfer medium disposed within the cavity so as to couple the diaphragm to the pressure sensing device.

Abstract: A device for determining a pressure of gas in an evacuated chamber including a cylinder positioned in fluid communication with the evacuated chamber with the cylinder forming a compressed gas chamber, a reciprocating piston received within the cylinder and mounted for reciprocal movement therein, a port or valve for providing selective fluid communication between the compressed gas chamber and the evacuated chamber is disclosed. A drive mechanism is provided for reciprocating the piston between a retracted position, where the compressed gas chamber communicates with the evacuated chamber, and an extended position where communication between the compressed gas chamber and the evacuated chamber is interrupted, the position being a position where a pressure transducer determines that a predetermined pressure differential between the chambers has been reached.

Abstract: A flowthrough pressure sensor is provided which avoids the creation of crevices and creases that could provide difficult to cleanse regions. The pressure sensor is particularly adapted for use in applications that require cleansing to avoid the build up of bacterial-laden material. The flowthrough pressure sensor is particularly adapted for use in the measurement of bodily fluids. A first conduit is connected in fluid communication with the second conduit which, in turn, is associated with a pressure sensitive element and two compressible seals. A housing member is provided with an opening into which the compressible seals in the pressure sensitive element are disposed. A latching mechanism is provided to force the housing against a boss portion of the first conduit so that the seals and the pressure sensitive element are compressed therebetween.

Abstract: A built-in amplifier type combustion pressure sensor which can be assembled by simplified operation. A pressure detecting device is fixed to one end of a housing with leads extending inside the housing. The leads are bent in a predetermined form by inserting a spacer and a cover from an opening of the housing located on the opposite side of the pressure detecting device. An amplifier circuit board is inserted into the housing from the opening so that the leads are inserted into holes provided on the amplifier circuit board and protrude from the surface of the amplifier circuit board facing the opening side. The protruding end of each lead is connected to the amplifier circuit board.

Abstract: A pressure measuring apparatus comprising a seal diaphragm that separates a fluid to be measured from a pressure transmitting medium that transmits a pressure variation of the fluid to be measured to a pressure detecting section. In such an apparatus, a non-electrically conductive film is coated on a surface of the seal diaphragm which is on the side of the fluid to be measured. As a result of the above construction, the pressure can be measured accurately over a long period of time while preventing hydrogen from passing through the seal diaphragm surely and protecting the seal diaphragm.

Abstract: A pressure sensor has a housing (1). The housing accommodates a pressure sensing element (2) and a wiring board (3). The wiring board incorporates a lead irame (14). The lead frame connects output terminals (21) of the sensing element with ends of connector pins (12). A pressure guide (4) has a pressure path (41) and a flange (44). The flange is inserted in an opening of the housing with the pressure path being airtightly connected to a pressure intake (22) extending from the sensing element and with an end face (4a) of the flange being spaced apart from the wiring board. Potting material (5) coats the sensing element, the wiring board, and the flange of the pressure guide in the housing. If the potting material peels off the flange, water may penetrate the peeled part and reach the end face of the flange. The water, however, never reaches the wiring board because the end face of the flange is spaced apart from the wiring board.

Abstract: The invention is related to numerous improvements for fiber optic measuring systems, and principally those utilizing a deformable diaphragm for sensing pressure. One feature of the invention is particularly oriented to automotive engine combustion chamber pressure measurement. For that application, a sensing tip shielding technique is described using a sintered metal porous plug, which reduces temperature fluctuations experienced at the sensing tip and shields the sensing tip from corrosive materials. A technique for compensation of a fiber optic pressure sensor is also described. In that method, a referencing wavelength is partly reflected and partly transmitted past a filter coating at the sensing end of the optical filament. This technique of the sensor provides improved calibration.

Abstract: A semiconductor type differential pressure measurement apparatus is disclosed comprising a measuring diaphragm having its periphery fixed, and two measuring chambers, each having a predetermined spacing along both surfaces of the measuring diaphragm, and which detects differential pressure within allowable limits of measurement. When an overpressure is applied, the diaphragm is stopped by a wall of a measuring chamber to prevent the diaphragm from being damaged by overpressure, so that no additional mechanism is required to prevent damage from overpressure. One embodiment utilizes an additional chamber and overhang to reduce overpressure. Another embodiment utilizes a measuring chamber having the two sides of the diaphragm exposed to the ambient to eliminate need for a pressure resistant casing. In a further embodiment, injected impurities serve as a terminal.

Abstract: A pressure sensor comprising a passage for introducing a pressurized medium; a member surrounding the passage; first and second sealants disposed between the member and the passage for preventing the pressurized medium from leaking to the outside through a clearance between the member and the passage; and a pressure sensing element communicating with the passage; the first sealant being made of a first material which is difficult to be deformed by the pressurized medium; the second sealant being made of a second material having a sealing effect against temperature change; the first and second sealants being arranged in series between the passage and the member surrounding the passage.

Abstract: A pressure gauge adapted for use in measuring the pressure of a thixotropic fluid subject to aggregation stagnation in which aggregation of the fluid is prevented by controlling stagnation of a magnetic coating liquid in the vicinity of a pressure sensor, and product quality is improved by removing air mixed into the liquid. An outlet is formed at the vertex of a conical holder. An inlet is formed in the conical surface of the holder at a location offset from the center of the cone defining the holder, which is contained in the outlet. A pressure indicator is mounted in the opening portion in the plane of the cone defining the holder.

Abstract: A transducer sensing element isolation assembly including a pressure housing having a chamber in which the sensing element is disposed, which sensing element communicates with the interior of a bellows through a sealing element disposed between the pressure housing and a base on which the bellows is secured. The chamber, bellows interior and sealing element are filled with a dead volume of low compressibility, low thermal expansion isolation fluid. The bellows is contained in a replaceable bellows capsule which is threaded into a bellows capsule cavity into which the chamber communicates, and the sealing element is maintained in place by the capsule being made up into the cavity.

Abstract: In a semiconductor sensor having double diaphragm structure, in which pressure to be measured is applied to diaphragm portions having distortion gages via a liquid filled in spaces partitioned by sealed diaphragms, as circuit elements of a signal processing circuit for processing an output of a distortion gage bridge are integrated in and on a semiconductor chip having diaphragm portions, the number of component parts used is reduced, and a compact size, a low cost, and high reliability are attained. This arrangement can be applied to any of the pressure sensors for detecting absolute pressure, relative pressure, and differential pressure.

Abstract: A transducer which provides a regulated pneumatic output as a function of an electric control input includes a housing, a gas regulator, and a particle trap. The housing has a passage therein, the passage including an inlet for receiving a pressurized gas supply and an outlet. The particle trap is disposed in the passage and includes a trap plate and a trap nozzle which directs gas against the trap plate so as to remove undesired entrained particles from the gas before it reaches the gas regulator.

Abstract: A pressure sensor unit having a pressure chamber formed in a housing by a plate member having a diaphragm region. The plate is fastened to the housing via an adhesive which is disposed in a joint between an inner housing surface and an intermediate support member which limits the movement of the adhesive in a direction transverse to the pressure direction.

Abstract: A beam-type strain gage pressure transducer is disclosed having strips of piezo-resistive material supported on a sensing beam, one being subject to compression and another to tension in response to applied pressure. The beam structure may be made by screw machine techniques to form a beam integral with a circular base structure. A highly flexible diaphragm permits force generated by application of pressure to be transmitted entirely to the beam. Components and construction are suited to high production and automated assembly techniques.

Abstract: A simple, reliable and inexpensive ultra high pressure transducer includes a basic capacitive transducer, made of two closely spaced insulating plates whose opposed faces contain conductive layers, and one of which plates is a thin and flexible diaphragm of low mechanical hysteresis. In mechanical coupling proximity with this insulating diaphragm is a thick metal diaphragm which is a part of the ultra high pressure coupling component. The flexure of this thick metal diaphragm under ultra high pressures, which are applied only on the side opposite the insulating diaphragm, determines the magnitude of the deflection of both diaphragms, and, corresponding to the resultant output capacitance level, provides a measure of the ultra high pressure level.

Abstract: A pressure sensing transmitter is provided that has high overpressure protection. The transmitter includes an housing having a first cell, a second cell, a sensing chamber, first and second pressure signal receiving means, and a differential sensor chip for measuring the pressure differential between the first and second pressure signal receiving means. Each cell further includes a cylinder with a clearance of an overpressure diaphragm mounted on the housing, an isolation diaphragm mounted on the other face, and a channel coupling the overpressure and isolation diaphragm and further coupling one cell to the first pressure signal receiving means and the other cell to the second pressure signal receiving means. Each overpressure diaphragm is positioned such that an overpressure protection cavity is formed between it and the housing. The first cell cavity is further coupled to the second pressure signal receiving means and the second cell cavity is further coupled to the first pressure signal receiving means.

Abstract: A pressure sensor for detecting pressure in a combustion chamber of internal combustion engines has a housing, a sensor element composed of a piezoresistive material and arranged in the housing, a diaphragm, a punch introducing a pressure to be determined onto the sensor element and located between the diaphragm and the sensor element. The punch has a counterbearing, a hybrid has a base, and a preprocessing circuit has electronic components. The sensor element, the hybrid with its base and the electronic components of the preprocessing circuit are located on the counterbearing of the punch.

Abstract: A transducer assembly includes a cap readily removable from a housing and enclosing a pressure transducer and a main valve body. Seals are located inside the housing which often are elastomeric or otherwise heat damageable. A top cartridge together with all of the seals inside the housing is readily disconnectable from the housing to separate the seals from the transducer assembly first end. This first end may then be heat sealed by soldering, brazing, or welding to a manifold or the like without any heat damage to the various seals. The transducer assembly then may be readily reassembled to form an operative transducer assembly. The foregoing Abstract is merely a resume of general applications, is not a complete discussion of all principles of operation or applications, and is not to be construed as a limitation on the scope of the claimed subject matter.

Abstract: A pressure transducer for measuring the pressure of a fluid comprising a housing having a cavity. A diaphragm capable of displacement is located within the cavity, dividing the cavity into a first and second chamber. The first chamber is capable of receiving a fluid to be measured, typically a liquid or a gas, while the second chamber contains a liquid such as a silicon oil. The second chamber also contains a gas and means for measuring the displacement of the diaphragm. Upon pressure being exerted against the diaphragm from the fluid, the diaphragm displaces against the liquid and gas, compressing and dissolving the gas as pressure is increased. Displacement of the diaphragm is measured by a measuring device, such as a strain gauge. When the gas is fully dissolved, further movement of the diaphragm is limited by the compressibility of the liquid.

Abstract: A head-gauge/tank-bladder device for measuring the pressure of liquid within a tank. The invention provides for measuring the tank pressure while maintaining the gauge isolated form the liquid within the tank. The invention is connects a gauge to a fluid filled tank through at least one threaded connection. On the other end of the tube, a bladder is attached. A liquid contained within the tubing transmits the tank fluid pressure to the gauge.

Abstract: A transmitter with a flame arresting header senses a pressure of a process fluid with a diaphragm which is sealed to the header. The diaphragm transfers the pressure of the process fluid acting an outer surface of the diaphragm to a fill fluid that isolates an inner surface of the diaphragm, and a pressure sensor enclosed in the transmitter senses the pressure of the fill fluid providing an output representative of the pressure of the process fluid. The header includes a chamber on the header's outer face and a passageway extending from the chamber to a tapered opening inside the transmitter with a first portion adjacent to the tapered opening shaped to receive an inlet tube leading to the sensor and a second flame isolating portion open to the chamber. The fill fluid fills the chamber, the passageway, and the inlet tube and is sealed in with a tapered seal pressed into the tapered opening around the inlet tube.

Abstract: A pressure sensor for detecting pressure in a combustion chamber of internal combustion engines has a housing, a sensor element arranged in the housing and composed of a piezoresistive material, a diaphragm, and a punch arranged between the diaphragm and the sensor element and introducing a pressure to be determined onto the sensor element. The punch has an end facing the sensor element, at least the end of the punch is composed of relatively soft material.

Abstract: Apparatus for measuring the pressure within a fluid-conveying member of a mixture of a fluid and particulate solids comprises an outlet port in the fluid-conveying member, a buffer vessel having walls defining a buffer volume for containing a buffer medium, the buffer vessel having first and second end portions, and having a measuring outlet at the first end portion being in fluid communication with the outlet port of the fluid-conveying member. An impulse conduit has its first end in fluid communication with the second end portion of the buffer vessel and a fluid pressure measuring device is in fluid communication with the second end of the impulse conduit. A source of purging medium is in fluid communication with the second end portion of the buffer vessel. The flow of the purging medium is controlled to establish a back pressure in the buffer vessel sufficient to prevent particulate solids which flow into the buffer vessel from the fluid-conveying member from reaching the impulse conduit.

Abstract: An isolator for use in pressure transmitters for isolating the process fluid being sensed from a sensor, comprises an isolating diaphragm that is thin, and made of a suitable corrosion resistant metal, such as tantalum, and which must be anchored to an isolator housing made of a substantially different metal such as stainless steel. Tantalum is very resistant to corrosion, and is a high melting point metal, which is substantially higher than the material comprising the sensor housing so direct welding is virtually impossible. The present invention relates to securing a support ring of the same metal as the diaphragm surrounding the cavity formed for the isolator fluid, preforming a thin metal diaphragm made of the selected material, and then welding the diaphragm and a ring overlying the diaphragm directly to the support ring.

Abstract: The invention features a melt pressure measurement device for measuring the pressure of a melted substance useful in cooled state for forming solid objects. The device comprises a probe for insertion through an aperture in a wall of a melt-containing vessel, with the probe having a pressure-deflectable end surface for contact with pressurized melt. The probe has pressure-resistant securing means for fixing the probe in the wall with the end surface of the probe exposed for contact with the melt in a non-flow obstructive relationship. A seal surface on the probe between the end of the probe and the securing means provides cooperative sealing action with a mating sealing means associated with the wall to prevent exposure of the melt to the securing means. The probe also has pressure detection means internal of the probe, responsive to deflection of the end surface of the probe, for detecting pressure of the melt.

Abstract: A pressure sensor comprising a pressure sensing assembly 24 and a pressrue transmitting medium 26 disposed within a main body 20 a seal assembly 34,35,36 disposed between the pressure sensing assembly and the main body for sealing between them against said pressure transmitting medium while allowing an easy attachment and detachment of the pressure sensing assembly relative to the main body. The pressure sensing assembly may comprise a sensing element 27 for detecting pressure, a base plate 25 for sealingly supporting the pressure sensing element within the main body and a pressure transmitting pipe 26 for transmitting the pressure to be detected to the element, and an O-ring in contact with the pressure transmitting pipe. A filling passage 15 which may be closed by a plug screw 16 may be disposed in the main body for filling the detection cavity with the pressure transmitting medium.

Abstract: Blood pressure measurements are performed on subjects disposed in hyperbaric chambers. The measurements are made by an automatic blood pressure monitoring instrument having a differential pressure transducer component. The pressure on the reference side of the pressure transducer is equal to the pressure in the hyperbaric chamber. The reference pressure is derived from a pressure source which equals the pressure in the hyperbaric chamber, but which pressure source does not contain the high purity oxygen gas in the hyperbaric chamber.

Abstract: A pressure sensor comprising a hollow main body (11) defining a bore (14) extending therethrough and having a detection end and an output end. A pressure sensing assembly is disposed within said bore (14) to divide it into a detection cavity (17) and an output cavity (18) through which output signal lines from said pressure sensing assembly extend. A flexible diaphragm (19) is attached to the detection end of the bore to define a sealed detection cavity (17) in which a pressure transmitting liquid is filled. The pressure sensing assembly comprises support plate (24) welded to said main body (11) and supporting a pressure sensing element (26) within said detection cavity (17) through a mounting bed (4). The signal lines sealingly extend through said support plate (24) from said detection cavity (17) to said output cavity (18).

Abstract: A semiconductor pressure-detecting apparatus includes a semiconductor chip having a diaphragm and a frame molded within a resin with the diaphragm exposed. A reference pressure chamber may be provided between the diaphragm and the frame. Since the diaphragm is exposed, a medium, the pressure of which is to be measured, easily contacts the diaphragm. Therefore, if the stem is connected to a case containing the medium, a high pressure can be measured.

Abstract: A semiconductor pressure sensor is manufactured by integrally encapsulating a semiconductor pressure, sensor chip, a pedestal, leads, wires and a die pad in an outer package except for the surface of a diaphragm of the semiconductor pressure sensor chip and the reverse side of the die pad. The ratio of the thickness of the pedestal to the thickness of the semiconductor pressure sensor chip is 7.5 or less, while the ratio of the diameter of an opening formed in the outer package at the surface of the diaphragm and the diameter of the diaphragm is 1 or more. The thermal stress generated in the semiconductor pressure sensor chip can freely be reduced to a desired value, and a semiconductor pressure sensor exhibiting a desired accuracy can therefore be obtained. Furthermore, since the semiconductor pressure sensor can be manufactured by an ordinary IC manufacturing process, a semiconductor pressure sensor with reduced cost and having high quality can be produced.

Abstract: A pressure sensor for determination of pressure in a combustion chamber of an internal combustion engine, particularly for motor vehicles has a housing, a membrane associated with the housing, a sensor element, a plunger supplying a pressure to be determined to the sensor element and located in the housing. The housing has at least one housing opening and a shaft and the membrane closing the opening of the housing and is connected with the shaft of the housing in the region of a side wall so that a bottom of the membrane is flexible and a pressure to be determined is transferable to the plunger, a counter bearing for the plunger. A support is provided for a hybrid and composed of ceramic material and located on the counter bearing for the plunger. The sensor element is a piezoresistive measuring element and located on the hybrid so as to produce an electrical signal corresponding to the pressure.

Abstract: An isolator for use in pressure transmitters for isolating the process fluid being sensed from a sensor, comprises an isolating diaphragm that is thin, and made of a suitable corrosion resistant metal, such as tantalum, and which must be anchored to an isolator housing made of a substantially different metal such as stainless steel. Tantalum is very resistant to corrosion, and is a high melting point metal, which is substantially higher than the material comprising the sensor housing so direct welding is virtually impossible. The present invention relates to securing a support ring of the same metal as the diaphragm surrounding the cavity formed for the isolator fluid, preforming a thin metal diaphragm made of the selected material, and then welding the diaphragm and a ring overlying the diaphragm directly to the support ring.

Abstract: This invention provides a semiconductor film pressure sensor in which the pressure-sensitive resistance layers are made of an n-type polycrystalline silicon layer, and a method of manufacturing the sensor. In the semiconductor film pressure sensor of the invention, the pressure-sensitive resistance layers are formed on a diaphragm, and in addition a coarsely adjusting pattern and a finely adjusting pattern for zero point adjustment and the resistors of a temperature compensating circuit are formed on the diaphragm using the same n-type polycrystalline silicone layer. In formation of the n-type polycrystalline silicone layer, the substrate temperature is held at 500.degree. to 600.degree. C. The coarsely adjusting pattern and finely adjusting pattern for zero point adjustment, and the resistors of the temperature compensating circuit are formed in the same step as the pressure-sensitive resistance layers.

Abstract: A ceramic capacitive pressure transducer capable of withstanding high pressures without undue internal stresses incorporates a deflecting diaphragm having a three-dimensional contoured surface adjacent a central electrode bearing region and within a rigid periphery. A planar electrode bearing region of predetermined thickness is defined by a concavity on the pressure receiving side, limited by a shoulder at the periphery, and a groove on the electrode bearing side. This configuration primarily deforms in the contoured region, with tensile stresses arising from interior deflection of the electrode bearing region and rigid seating of the periphery being distributed through the groove region and also cancelling to some extent such that axial, radial and tangential stresses all are held well below allowable stress levels for the material.

Abstract: A pressure sensor comprising a case, a diaphragm provided within the case, a pressure detecting part provided within the case for detecting pressure applied to the diaphragm, and a pressure transmission chamber formed between the diaphragm and the pressure detecting part for sealingly accommodating therein liquid through which the pressure is transmitted from the diaphragm to the pressure detecting part. The pressure transmission chamber is arranged to cope with the volume changes of the liquid due to the temperature changes thereof.

Abstract: The invention relates to a device for measuring pressures or forces, comprising a pressure or force sensor in the form of a piezoelectric or piezoresistive pressure or force transducer having at least one electric cable connected thereto, and an incompressible elastomer mass which transmits the pressure or force to be measured to the transducer.

Abstract: A pressure transducer apparatus having a flexible shock absorber in direct contact with the sensing element of a pressure transducer to prevent the direct application of harmful external environmental elements. A metal disk is located on the top of the shock absorber to provide mass for absorbing particle momentum. An air gap surrounding the shock absorber provides space for radial expansion of the shock absorber.

Abstract: The apparatus for sensing pressure comprises a header, having at least one input port for receiving a substance under pressure. A substrate, having a wafer-like shape with a relatively large surface area in comparision to its thickness, includes at least one internal passage to couple the substance under pressure. A pressure sensing element is mounted onto the surface of the substrate over an exit port of the internal passage coupling the substance under pressure. The substrate is bonded to a surface of the header at extreme locations from a location in which the pressure sensing element is mounted. Thus isolation is provided for the pressure sensing element from unwanted stresses induced in the substrate.

Abstract: A pressure sensor package, having a dual-in-line package (DIP) structure as commonly used in the semiconductor industry, comprises a first layer of predetermined material, having at least one internal passage for transmitting a fluid under pressure from a first surface of the first layer to a second surface of the first layer. A pressure sensitive element is bonded to the first surface of the first layer, and covers an exit from the first surface of the internal passage. A lead package, has a plurality of pins, each pin being perpendicular to the first surface of the first layer and placed along a first and second length of the first layer exterior to the pressure sensor package, and having a spacing conforming to the DIP configuration. Predetermined points of the pressure sensitive element are electrically connected to predetermined pins. A second layer of predetermined material is bonded to the first surface of the first layer providing an enclosed spaced for the pressure sensitive element.

Abstract: A flush-mounted sensor measures the pressure of a fluid at a given point of a fluid system such as a container or conduit. A sensor head edge-mounts an isolating diaphragm responsive to the pressure of the fluid. The isolating diaphragm has a small diameter in comparison with the dimensions of the fluid system, is adjacent to the fluid in the system to reduce the dead volume of fluid adjacent the diaphragm and may be formed of a material that is compatible with the fluid. A drive rod mechanically couples the isolating diaphragm to a second diaphragm of a variable capacitor assembly, preferbly one of the center-mounted type where the diaphragm is one plate of the capacitor. The second diaphragm is also edge-mounted and produces a counterforce acting on the side of the isolating diaphragm opposite the side adjacent the fluid.

Abstract: A pressure sensor particularly for measuring pressure within a diesel fuel pump comprises a screw-threaded bolt having a head and a shank and having a bore extending through the bolt through the head and shank. A transducer comprising a piezoelement is disposed in the bore, an electrical terminal extends from the bore through the head of the bolt, an electrical insulator is disposed between the transducer and bore, a threaded element positions one side of the transducer in the bore against the terminal, a spring in the bore extends from the shank end of the bore to bear against the opposite side of the transducer, and an incompressible material surrounds the spring in the bore to transmit a pressure force from a fluid pressure zone in the pump through the shank end of the bore to the transducer to provide a signal from the transducer representative of the pressure in the zone.