Abstract: A pressure sensor has a diaphragm with a first layer and a second layer, a pressure transmitting member being in contact with the second layer, and a sensing element. The diaphragm is deformable in response to a pressure applied on a front surface of the first layer. The transmitting member transmits this pressure to the sensing element. The sensing element detects the pressure. A heat applied to the diaphragm induces the layers to be shifted toward the transmitting member or the opposite side of the transmitting member due to a shape of the diaphragm. The layers of the diaphragm have thermal expansion coefficients differing from each other. A thermal deformation of the layers caused by the thermal expansion difference between the layers cancels out the thermal deformation of the layers originated in the shape of the diaphragm.

Abstract: A pressure sensor assembly for sensing a pressure of a process fluid includes a sensor body having a cavity formed therein to couple to a process fluid pressure. A deflectable diaphragm in the cavity deflects in response to the first and second process fluid pressures. A first primary electrode couples to a wall of the cavity and forms a first primary capacitor between the first primary electrode and the deflectable diaphragm. A first secondary electrode couples to the wall of the cavity to form a first secondary capacitor between the first secondary electrode and the deflectable diaphragm. A second primary electrode and second secondary electrode are preferably coupled to a wall of the cavity opposite the first. Line pressure of the process fluid is determined based upon variation in the secondary capacitors relative to the primary capacitors.

Abstract: A method of making a force sensor, the force sensor being particularly sensitive the axial component of a force applied along a predetermined axis, of the type including a force-receiving membrane deformable by an applied force to be sensed, the method comprising: providing the force sensor with a body of a liquid, and with a second membrane separated from said force-receiving membrane by the body of liquid; applying the force to be sensed to the center of the force-receiving membrane to thereby pressurize the liquid according to the magnitude and axis of the force applied to the force-receiving membrane; and measuring the deformation of the second membrane; wherein the force-receiving membrane is of a non-undulating configuration in its normal condition and is deformable, by a force applied to its center at an oblique angle to its surface, into an undulating configuration, to include an inwardly-bowed section on one side of its center, and an outwardly-bulged section on the opposite side of its center, such

Abstract: A pressure detection device includes a sensing part that is provided at one end portion of the housing to output an electrical signal responsive to an applied pressure, a circuit part that is provided at an other end portion of the housing to process the signal from the sensing part, and a flexible printed board provided in the housing between the sensing part and the circuit part. Furthermore, the flexible printed board has a first end portion electrically connected to the sensing part at a first connecting part, and a second end portion electrically connected to the circuit part at a second connecting part. In the pressure detection device, the flexible printed board is shaped between the first and second end portions to relieve a stress applied to the connecting parts.

Abstract: A probe includes a sensor having a pressure-sensitive surface, electrical signals being producible by the sensor when pressure forces are acting that have a directional component orthogonal to the pressure-sensitive surface. The probe includes a probe element, which is supported in a movable manner relative to the sensor, and a mechanical transmission element. The probe includes a diaphragm, which is arranged between the transmission element and the pressure-sensitive surface of the sensor. The probe element, the transmission element, the diaphragm and the sensor are in a mechanical operative connection such that by contacting the probe element, a change in the level of the electrical signal is producible by the sensor.

Abstract: A piezoelectric sensor, preferably a pressure sensor, comprising at least two piezoelectric measuring elements placed in a housing, which are clamped between a membrane on the pressured side of the housing and a pick-up electrode electrically insulated against the housing. The piezoelectric measuring elements are fixedly attached to the pick-up electrode by thermo-compression or soldering and together with said pick-up electrode form a compact measuring element stack, which will significantly simplify assembly of the piezoelectric sensor.

Abstract: A fluid flow indication apparatus is provided for monitoring and giving an indication of fluid flow.

Abstract: A pressure-difference sensor, which is asymmetrical by design, includes a measuring apparatus having a first half-chamber with a first volume V1, which is sealed by a first separating membrane having a first membrane stiffness E1, and a second half-chamber with a second volume V2, which is sealed by a second separating membrane having a second membrane stiffness E2, wherein the first half-chamber is separated from the second half-chamber by a pressure sensitive element, especially a measuring membrane, and the first half-chamber is filled with a first transfer liquid having a first coefficient of thermal expansion ?1 and the second half-chamber is filled with a transfer liquid having a second coefficient of thermal expansion ?2.

Abstract: A fluid pressure sensor (1) for measuring the pressure of a fluid comprises a diaphragm portion (12) which is a strain generating body, a silicon oxide film (21) as an insulating film, and a strain gauge (20) made of crystalline silicon, and austenitic precipitation hardening type Fe—Ni heat-resisting steel excellent in mechanical strength and corrosion resistance is used for the diaphragm portion (12). The silicon oxide film (21) is formed with the internal stress thereof adjusted to the range from ?150 to 130 MPa. With this feature, the fluid pressure sensor (1) ensures high precision and reliability, and may be used even for measurement of a highly corrosive fluid.

Abstract: A thin-film resistor (5) provided on a strain-generating part (2) via an insulating film (4) and an electrode thin-film (6) including an electrode pad (10) arranged in the thin-film resistor (5) are provided. The thin-film resistor (5) includes a strain-detecting thin-film resistive part (8) and an electrode connection (9) connected to the resistive part (8). The electrode connection (9) is formed to extend to the electrode pad (10). The electrode pad (10) includes an external-connection bonding area (12) and a testing probe area (13) formed at different positions. The electrode pad (10) is disposed on a tubular rigid body (1) provided at the outer peripheral edge of a strain-generating part (2).

Abstract: A piezoelectric sensor arranged so as to includes: a transparent piezoelectric element having a piezoelectric property; and a pair of transparent conductor film layers opposed to each other with the piezoelectric element therebetween, the transparent piezoelectric element and the transparent conductor film layers are formed between a pair of transparent substrates, opposed to each other, which serve as pressure transmission means. Consequently, the transparent piezoelectric sensor has an excellent durability. A piezoelectric sensor comprises a piezoelectric element with a piezoelectric property which is made of a piezoelectric material having no Curie point and has a dipole orientation degree of not less than 75%. Consequently, the piezoelectric sensor having an excellent durability and a simple structure is provided at low cost.

Abstract: A pressure transmitter for transfer of a pressure prevailing in a first medium onto a second medium, including a pressure chamber 4 in a platform 1, which chamber is separated from the first medium by means of a dividing membrane 2, wherein the pressure can be transferred by means of the second medium to a pressure measurement cell. For timely recognition of an impending failure of the dividing membrane, an early warning detector is provided with a sensor chamber 6 having an opening, which faces the first medium; and a sensor 7, which monitors a property of a medium container in the sensor chamber; and a barrier facing the first medium, pressure-tightly sealing the opening, and which, under contact with the first medium and equal conditions as experienced by the dividing membrane 2, fails earlier than the dividing membrane, thus making possible a flow connection between the sensor chamber 6 and the first medium.

Abstract: The pressure cell device according to the invention serves for measuring hydraulic pressures in hydraulic mining devices in an inherently secure service region. It is provided with a connection element which can be connected to a pressure reception connection and with a sensor housing, on the inside of which is arranged a hydroelectric pressure transducer which is pressurised by the hydraulic pressure present at the pressure reception connection and converts this into an electrical signal. So as to ensure high measurement accuracy over a long operating period, without it being necessary to have exchanges of the pressure transducer or its new calibration, it is provided according to the invention that the pressure transducer comprises a ceramic pressure measuring cell.

Abstract: The present invention lessens the amount of air entering between mating membranes of a pressure sensor. The pressure sensor of the present invention includes a transducer portion and separate patient or medical fluid transfer portion or dome. The transducer portion is reusable and the dome is disposable. The dome defines a fluid flow chamber that is bounded on one side by a dome membrane. Likewise, the transducer is mounted inside a housing, wherein the housing defines a surface that holds a transducer membrane. The two membranes mate when the dome is fitted onto the transducer housing. The pressure sensor enhances the seal between the mated membranes by creating higher localized contact stresses. The pressure sensor also reduces the amount of gas that permeates from the fluid chamber across the dome membrane and between the interface by making the dome membrane from a material having a low vapor transmission.

Abstract: A side-hole optical cane for measuring pressure and/or temperature is disclosed. The side-hole cane has a light guiding core containing a sensor and a cladding containing symmetrical side-holes extending substantially parallel to the core. The side-holes cause an asymmetric stress across the core of the sensor creating a birefringent sensor. The sensor, preferably a Bragg grating, reflects a first and second wavelength each associated with orthogonal polarization vectors, wherein the degree of separation between the two is proportional to the pressure exerted on the core. The side-hole cane structure self-compensates and is insensitive to temperature variations when used as a pressure sensor, because temperature induces an equal shift in both the first and second wavelengths. Furthermore, the magnitude of these shifts can be monitored to deduce temperature, hence providing the side-hole cane additional temperature sensing capability that is unaffected by pressure.

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 ?m. Accordingly, the pressure sensor effectively restricts a variation in a sensor characteristic due to a thermal change.

Abstract: A pressure sensor includes a silicon diaphragm having bottom and topside surfaces. The bottom surface has been formed using methods known to those skilled in the art. A first layer is formed and patterned on the topside surface of the diaphragm having an area larger than the diaphragm. A second layer is formed and patterned over the first layer, the second layer being larger in area than the first layer. Holes formed in the second layer are used to remove the first layer using methods known to those skilled in the art. A third layer is formed and patterned over the second layer. The third layer seals the holes in the second layer creating a sealed cavity with a reference pressure on the topside surface of the diaphragm. During operation, media is applied to the bottom surface of the diaphragm wherein the media pressure can be sensed by the pressure sensor in relation to the reference pressure sealed on the topside of the diaphragm.

Abstract: The object of the present invention is to propose an etch channel sealing structure characterized by excellent impermeability to moisture and resistance to temporal change of the diaphragm in the pressure sensor produced according to the sacrificial layer etching technique, and to provide a pressure sensor characterized by excellent productivity and durability. After a very small gap is formed by the sacrificial layer etching technique, silicon oxide film is deposited by the CVD technique or the like, thereby sealing the etch channel. Further, impermeable thin film of polysilicon or the like is formed to cover the oxide film. This allows an etch channel sealing structure to be simplified in the pressure sensor produced according to the sacrificial layer etching technique, and prevents entry of moisture into the cavity, thereby improving moisture resistance. Moreover, sealing material with small film stress reduces temporal deformation of the diaphragm.

Abstract: A pressure sensing capsule includes a pressure sensor inside a capsule wall. The capsule wall includes a feedthrough opening. The pressure sensor is mounted to a stress isolation member with a feedthrough hole. The pressure sensor is mounted to the stress isolation member with the feedthrough hole overlying electrical contacts on the pressure sensor.

Abstract: A differential pressure indicator has a housing with at least two ports in the housing. One port receives a first pressure, and the second port receives a second pressure. A pressure resistive device is placed between the first port and the second port. The pressure resistive device changes its position when the first pressure exceeds the second pressure by a predetermined amount. A magnet is coupled to the pressure resistive device. A digital displacement sensor senses the position of the magnet. The digital displacement sensor is in communication with an electronic indicator. The electronic indicator activates when the first pressure exceeds the second pressure by a predetermined amount.

Abstract: A method of manufacturing strain-detecting devices is provided. First, plural cylindrical substrates, each of which has one end closed by a diaphragm, are fixedly placed at predetermined positions of a fixing plate. A positioning marker is previously given to the fixing plate. The fixing plate having the substrates is then assembled into a jig. The jig sustains the substrates so that an outer surface of the diaphragm of each substrate is held at the same level. Through positioning the substrates, all the diaphragms are then positioned in place in a plane direction of the fixing plate with reference to the positioning marker. A strain gage portion is simultaneously formed on each of all the diaphragms. The fixing plate is then disassembled from the jig. In this step, the substrates with the strain gage portions, i.e., strain-detecting devices, are separated from the fixing plate.

Abstract: Transfer fluid, in particular for electrical pressure transducers and pressure transmitters, that transfers deflections of a separating element between a substance to be measured and the transfer fluid to a pressure measurement arrangement, the transfer fluid comprising a polyalphaolefin (PAO 6).

Abstract: A method of determining fouling of a filter includes the use of a differential pressure indicator which has a housing with at least two ports in the housing. One port receives a first pressure, and the second port receives a second pressure. A pressure resistive device is placed between the first port and the second port, and changes its position when the first pressure exceeds the second pressure by a predetermined amount. A magnet is coupled to the pressure resistive device. A digital displacement sensor senses the position of the magnet and is in communication with an electronic indicator. The electronic indicator activates when the first pressure exceeds the second pressure by a predetermined amount, thus allowing determination of filter fouling.

Abstract: A micromechanical component having a substrate and a diaphragm positioned on the substrate. Underneath the diaphragm a region made of porous material is provided, which mechanically supports the diaphragm and thermally insulates it.

Abstract: The invention relates to a process for providing a contact to a diaphragm electrode (6) that belongs to a pressure-measuring configuration, involving the following stages: the connection of a diaphragm (3) on which the diaphragm electrode (6) is positioned to a base (1) by means of a connecting element (2) made of an electrically insulating material running between the two, where the base exhibits a throughplating hole (7, 10) between an attachment point (8) and a connecting point (9) for the electrically insulating material, and the connecting element (2) exhibits a connecting element throughplating (11) between the connecting point (9) and the diaphragm or the diaphragm electrode; the provision of conductive contact material (13) in the throughplating hole (7, 10); and the activation of the contact material (13) by heating.

Abstract: A pressure sensor includes a membrane having a radially peripheral edge region fixedly arranged on a support. One side of the membrane can be acted on by a medium being measured and the membrane can be deflected in response to pressure of the medium. Measuring elements and an electric circuit interconnecting the measuring elements are arranged on the membrane, the measuring elements and the circuit being applied by the thick-film technique and sintered on in a thermal process. The membrane is made of an electrically conducting metal and bears an insulating layer, on which the measuring elements and the electric circuit are arranged. In this case, the insulating layer consists of a material having a coefficient of expansion that lies between the coefficient of expansion of the metal of the membrane and the coefficient of expansion of the material of the measuring elements and the electric circuit.

Abstract: An arrangement and method for determining one or more characteristics of a sample fluid, and a method to determine the one or more characteristic of the sample fluid, are provided. In particular, a first assembly is contained within a particular housing, and a second assembly is positioned externally from the particular housing. The first assembly includes a first sensor which may be adapted to obtain first data associated with a first characteristic of the sample fluid, and a particular electrical assembly which is electrically coupled to the first sensor, and may be adapted to determine the first characteristic of the sample fluid as a function of the first data. The second assembly includes a second sensor which may be adapted to obtain second data associated with a second characteristic of the sample fluid.

Abstract: A pressure instrument with a seal connection connecting a pressure gauge to a process. A pressure sensor located in a base of the seal connection is in data communication with the pressure gauge that is spaced apart from the pressure sensor. Embodiments are particularly applicable on sanitary seal connections or where a low measuring range or high accuracy is required. Embodiments can include, for example, digital pressure gauges, pressure transducers and transmitters with any seal connection.

Abstract: A pressure sensor that is particularly suitable inter alia for the food industry and the measuring accuracy of which is stable over a long time, having a diaphragm seal (3, 45) with a separating diaphragm (7, 53) on which a pressure (P) to be measured acts and having a ceramic measuring cell (9, 57) which is connected to the diaphragm seal (3, 45) exclusively by inorganic materials, is provided, in which sensor the separating diaphragm (7, 53) and all further sensor components coming into contact during measurement with a medium of which the pressure (P) is to be measured are metallic.

Abstract: A differential pressure indicator has a housing with at least two ports in the housing. One port receives a first pressure, and the second port receives a second pressure. A pressure resistive device is placed between the first port and the second port. The pressure resistive device changes its position when the first pressure exceeds the second pressure by a predetermined amount. A magnet is coupled to the pressure resistive device. A digital displacement sensor senses the position of the magnet. The digital displacement sensor is in communication with an electronic indicator. The electronic indicator activates when the first pressure exceeds the second pressure by a predetermined amount.

Abstract: A capacitive pressure sensor of substantially ceramic material comprises a thick base plate (100), a front plate (140) having the same thickness as the base plate and a movable diaphragm (120) located between the front plate and the base plate. Capacitor electrodes (121b, 121a) are provided at the surface of the diaphragm facing the base plate and form a measurement capacitor. The diaphragm (120) is extremely thin and is produced by sintering a ceramic material such aluminium oxide. Owing to a pressing process used during the sintering a strong, very thin diaphragm is obtained having no mechanical stresses and fracture indications. It can be produced to have a very small thickness in order to provide pressure sensors having a high sensitivity, which can also for high-vacuum applications tolerate to be subjected to the atmospheric pressure. A shielding plate (110) can be inserted between the base plate (100) compensating the measurement capacitor.

Abstract: The present invention relates to compact solid state silicon-based condenser microphone systems suitable for batch production. The combination of the different elements forming the microphone system is easier and more economical to manufacture compared to any other system disclosed in prior art. In addition the invention is compatible with electronic equipment manufacturing processes, such as SMD pick and place techniques. The invention uses a transducer chip comprising a chamber, a diaphragm that is positioned at the first lower surface and covering the second opening of the transducer chip. The transducer chip is flip-chip mounted onto a post-processed chip also comprising a chamber. The microphone system can be electrically connected to an external substrate by conventional techniques such as wire bonding.

Abstract: A pressure sensing unit has a pressure responsive member, a pressure sensor, and a hydraulic connector hydraulically connecting the pressure responsive member with the pressure sensor to produce an indication of sensed pressure. The hydraulic connector includes a tubular member and a longitudinal insert in the tubular member with hydraulic fluid in the tubular member between the insert and the member. The tubular member, the insert and the hydraulic fluid and the dimensions of the tubular member and the insert are such that the hydraulic fluid transmitted to the pressure sensor is substantially independent of temperature changes.

Abstract: A pressure cell contains a base body (1), a membrane (2) that is arranged on the base body (1) and can be deformed by a pressure to be measured, as well as a first and a second temperature sensor. The second temperature sensor is spaced apart from the first temperature sensor in the direction of a temperature gradient. Temperature shocks of the measuring cell can be determined and compensated by monitoring the difference between the temperatures measured by the sensors or changes in the temperatures measured by a sensor.

Abstract: The invention proposes a device for measuring the pressure of blood in a pipe (44) of an extracorporeal blood circuit (42) includes a pressure measurement section (46) having a substantially rigid wall (64) including a hole (66) which is sealed by a closure element (68), the internal face (70) of which is in contact with the blood and the external face (72) of which is in contact with the ambient air, it being possible for the closure element (68) to be elastically deformed overall along a deformation axis (A—A) under the effect of the blood pressure. The closure element (68) is made in a single piece with the associated rigid wall (64) of the pressure measurement section (46).

Abstract: A pressure sensor module for measuring a differential pressure has a sensor chip for measuring a differential pressures and a module housing with at least two lead lines that are disconnected from one another by the sensor chip and in which lines differential pressures are at least intermittently present, wherein in at least one lead line a valve is disposed that closes the lead line when the sensor chip no longer disconnects the lead lines from one another.

Abstract: A device for measuring the pressure of blood in a pipe (44) of an extracoporeal blood cicuit, includes a pressure measurement section (46) having a compartment (58) which is delimited especially by a main wall (64) and by a secondary wall (65) facing it. The two walls (64, 65) have a hole (66, 84) which is closed by a closure element (68, 86) which can be elastically deformed under the effect of the blood pressure, and the compartment (58) has a spacer (94) which transmits the movements from the closure element (86) of the secondary wall (65) to the closure element (68) of the main wall (64), so that a load sensor (56) can measure a force which corresponds to a so-called “negative” blood pressure.

Abstract: A pressure measurement device comprising a housing enclosing an elastic pressure measurement element and a magnet attached to the measurement element. First and second Hall sensors operatively positioned near the magnet are connected to an electrical circuit which processes the sensor outputs to provide first and second output signals. The positions of the Hall sensors can preferably each be adjusted from outside the housing.

Abstract: A piezoelectric sensor includes a carrier, a piezoelectric measurement sensing element arranged on the carrier, a covering layer covering the measurement sensing element and an electronic evaluation unit. The measurement sensing element is formed by a piezoelectric layer. The carrier has a first contact layer electrically connected to the piezoelectric layer and the covering layer has a second contact layer electrically connected to the piezoelectric layer. The electronic evaluation unit is able to determine a mechanical loading of the piezoelectric layer by evaluating the difference of electrical potential between the first contact layer and the second contact layer.

Abstract: A pressure mediator includes a base body 20; a divider diaphragm system having a first divider diaphragm 31 and a second divider diaphragm 21, between which an intermediate chamber is enclosed in pressuretight fashion, in which the first surface of the first divider diaphragm 321, remote from the intermediate chamber, can be acted upon by the pressure prevailing in the first medium, and the first surface of the second divider diaphragm 21, remote from the intermediate chamber, is oriented toward the base body and is secured by its peripheral region to the base body, forming a pressure chamber between the base body and the second divider diaphragm 31, and the pressure chamber can be filled with the second medium and has a pressure chamber opening, through which the pressure can be transmitted by means of the second medium, and an exertion of pressure of the first divider diaphragm can also be transmitted to the second divider diaphragm via the intermediate volume; and having a sensor 4, for monitoring a proper

Abstract: An improved pressure activated control apparatus is provided for sensing fluid pressure and triggering one or more switches in response to the fluid pressure, as desired. The apparatus is designed to be placed within a fluid of a reservoir. The apparatus includes a first resilient member, such as a pliable rolling diaphragm or bellofram, having an outer surface exposed to the fluid and responsive to the fluid pressure. The pressure activated control apparatus includes a second resilient member, such as a spring with a chosen spring constant, k, that provides a biasing force against the diaphragm that is opposite the fluid pressure. A transducer is operative to monitor changes in pressure of gases within the apparatus causes by movement of the diaphragm. A controller is responsive to the transducer and selectable fluid level thresholds to activate pumps and/or valves for adjusting the level of the fluid in the reservoir.

Abstract: A pressure sensor is mounted upon a hydraulic valve body. The sensor has a base which extends into a bore formed in the valve body. The valve body bore is in communication with a pressurized hydraulic fluid. A cover that is removably attached to the valve body encloses the pressure sensor. A circuit substrate is disposed within the cover and electrically connected to the pressure sensor.

Abstract: A method and device for void fraction measurement in a gas/liquid two-phase stratified flow system in disclosed. A couple of pressure-signal tubes are mounted to the through into the top and bottom walls of the horizontal pipeline portion of the flow system to measure the pressure differential value between the top and bottom interior position thereof. The height of liquid phase level of the stratified flow is calculated from the pressure differential value and the liquid-phase density. The void fraction is derived from the known geometric relation between the height of liquid-phase level and the cross section of the pipe. Each of the pressure-signal tubes is encased within a cylindrical cooling case to avoid flashing phenomenon from occurring within the pressure-signal tube. This method is applicable for the flow at steady or transient state under high temperature/pressure condition.

Abstract: It is an object of the present invention to provide a portable pressure measuring apparatus to be used as an altimeter, which can be automatically switched to an optimum sampling period in accordance with a use of the apparatus before a pressure measurement at all times. A portable pressure measuring apparatus additionally comprises a pressure/altitude operation section for obtaining an altitude from a measured pressure by an arithmetic operation, a rate of pressure change operation section, and a movement detecting section, wherein, if the movement detecting section detects a movement, a pressure is measured in a sampling period, for example, in a 1-second sampling period, if a rate of altitude change is equal to or greater than a threshold or in a sampling period, for example, in a 5-second sampling period, if the rate of altitude change is smaller than the threshold and wherein, unless the movement detecting section detects any movement, the pressure sampling measurement is not performed.

Abstract: An electronic pressure-sensing device is isolated from corrosive, conductive gasses and fluids by a corrosion resistant metal diaphragm welded to a pressure port. The pressure-sensing device is attached to a support structure with a hole that provides a path from the diaphragm area to the pressure-sensing device. A fill fluid is sealed behind the diaphragm and fills the hole through the support structure to the electronic pressure-sensing device. In this design, any hostile chemical applied is completely isolated from the electronic sensor and associated adhesive seals by the metal diaphragm.

Abstract: A method of manufacturing an air pressure sensor is disclosed. A plurality of sensor circuitry modules are formed on a first side of a silicon wafer. A plurality of cavities on a second side of the silicon wafer are formed. Each of the plurality of cavities is aligned with one of the plurality of sensor circuitry modules. A glass wafer is attached to the second side of the silicon wafer. The silicon wafer and the glass wafer are cut such that a single sensor circuitry module is separated from the other sensor circuitry modules and a portion of the glass wafer remains attached to the sensor circuitry module so that the cavity opposite the sensor circuitry module is enclosed by the portion of the glass wafer to form a reference pressure chamber therebetween. The sensor circuitry module is flexibly mounted to an interior surface of a sensor housing. The sensor circuitry module is electrically connected to external conductive connectors.

Abstract: The invention pertains to differential pressure transducers for gas turbine motors, for measuring variable pressure differences within a medium or between different media. The differential pressure transducer is constructed as a linear displacement sensor according to the linear variable displacement transducer (LVDT) principle, and has a ferromagnetic core that can be moved in a translatory manner, a spring element for the set position of the core given nominal differential pressure, a primary coil and two secondary coils arranged in succession axially over the length of the stroke range of the core, and a tubular housing having a delivery connection on both sides of the stroke area of the core.

Abstract: An ultrasensitive displacement sensing device for use in accelerometers, pressure gauges, temperature transducers, and the like, comprises a sputter deposited, multilayer, magnetoresistive field sensor with a variable electrical resistance based on an imposed magnetic field. The device detects displacement by sensing changes in the local magnetic field about the magnetoresistive field sensor caused by the displacement of a hard magnetic film on a movable microstructure. The microstructure, which may be a cantilever, membrane, bridge, or other microelement, moves under the influence of an acceleration a known displacement predicted by the configuration and materials selected, and the resulting change in the electrical resistance of the MR sensor can be used to calculate the displacement. Using a micromachining approach, very thin silicon and silicon nitride membranes are fabricated in one preferred embodiment by means of anisotropic etching of silicon wafers.

Abstract: Unwanted gasses created during bonding within micromachined vacuum cavities are reduced in a manner conducive to mass manufacturing. Two broad approaches may be applied separately or in combination according to the invention. One method is to deposit a barrier layer within the cavity (for example, on an exposed surface of the substrate). Such a layer not only provides a barrier against gases diffusing out of the substrate, but is also chosen so as to not outgas by itself. Another approach is to use a material which, instead of, or in addition to, acting as a barrier layer, acts as a getterer, such that it reacts with and traps unwanted gases. Incorporation of a getterer according to the invention can be as straightforward as depositing a thin metal layer on the substrate, which reacts to remove the impurities, or can be more elaborate through the use of a non-evaporable getter in a separate cavity in gaseous communication with the cavity.

Abstract: A pipe having a through-hole of smaller diameter than a pressure port is disposed in the pressure port. Therefore, a volume of the pressure port can be reduced by the thickness of the pipe, thereby improving response of a pressure sensor. Furthermore, there is no need for the pressure port having smaller diameter to be provided by drill processing, so that a volume in the pressure port can be easily adjusted. Accordingly, the volume in the pressure port can be reduced with a simple structure to improve response of the pressure sensor.