Abstract: A vacuum aspiration control system for use with a vacuum source and an aspiration catheter includes a connecting tube configured to connect the vacuum source with a lumen of an aspiration catheter. An on-off valve is operatively coupled to the connecting tube, and a sensing unit is configured to detect flow within the connecting tube and provide a signal representative of flow. A controller receives the signal to decide whether to open or close the valve. The controller may automatically close the valve to stop flow when flow through the connecting tube is unrestricted, or according to a predetermined timing sequence. The controller can further periodically open a closed valve to determine whether flow has entered an acceptable range. The controller can still further engage pulsed aspiration with a pressure manipulation assembly when flow is restricted or occluded.

Abstract: A universal fitting for in-line fluid measurement in a process application. The fitting includes an inlet and outlet port and also has a body with a fluid flow passage providing fluid communication between the ports. A sensor housing is provided that extends outwardly away from a wall of the body, wherein the housing is sized to receive a sensor assembly, which assembly measures at least one characteristic of the fluid. A base of each housing integrally formed with the wall and including a sensor seat for receiving a portion of the sensor assembly. A probe aperture receives a probe portion of the sensor assembly, each housing having the probe aperture disposed in the wall and extending from the fluid passage through its respective sensor seat.

Abstract: Methods and systems may provide for technology to collect data related to tire pressure of a vehicle via one or more tire pressure monitoring sensors (TPMS), and provide a warning for a low or high tire pressure based on weather patterns determined by a historic weather data subsystem. The weather patterns may include fluctuations and steady states of temperature. A TPMS machine learning subsystem may use tire pressure data and weather data to provide an alert as to whether an indicator associated with the one or more TPMS sensors was activated due to changing weather. The TPMS machine learning subsystem may also determine a probable accuracy of the TPMS alert based on the TPMS data and weather-related data including checking for outliners in the weather patterns.

Abstract: A sensing system comprises at least one gauge disposed in a wellbore, a sensing link coupled to the at least one gauge, and a debris barrier coupled to the sensing link. The debris barrier comprises a housing coupled to the sensing link, and a barrier element configured to reduce the transport of particulates from the wellbore into the sensing link.

Abstract: A strain sensor system emits coarse interrogation signals of different frequencies during a coarse scan while an RF resonant sensor and/or an RF interrogator moves relative to the other. The sensor emits responsive RF signals within a frequency range of a frequency of interest of the sensor. The controller identifies the frequency of interest based on receipt of the responsive signals. The interrogator emits fine interrogation signals of different frequencies during a fine scan subsequent to the coarse scan. The fine signals are emitted at frequencies within a frequency band on both sides of the frequency of interest. The sensor emits responsive RF signals and the controller identifies a center frequency of the RF resonant sensor based on receipt of the responsive signals.

Abstract: Apparatus and related fabrication methods are provided for a sensor device. An exemplary sensor device includes a first structure including a first sensing arrangement and a second sensing arrangement formed therein and a second structure affixed to the first structure. The second structure includes a cavity aligned with the first sensing arrangement to provide a first reference pressure on a first side of the first sensing arrangement and an opening aligned with the second sensing arrangement to expose the first side of the second sensing arrangement to an ambient pressure.

Abstract: A pressure sensor includes: a housing; a pressure receiver which seals an opening of the housing and transmits pressure from outside the housing to the inside of the housing; and a pressure sensing element having a pressure sensing portion and a pair of base portions which are respectively coupled to both ends of the pressure sensing portion. In the pressure sensor, a force detecting direction is set to be a detection axis, a line connecting the pair of base portions and a displacement direction of the pressure receiver are arranged in parallel, one of the base portions is coupled to a central region, which is displaced by the pressure, of the pressure receiver, and the other of the base portions is coupled to a marginal region, which is at a fixing side, of the pressure receiver through a connecting member.

Abstract: A pressure sensor includes a sensor body with a sensor chamber in the interior, at least a first separating membrane, forming a first separating membrane chamber connected with the sensor body. A measuring membrane divides the sensor chamber into two chamber portions. A pressure transfer liquid, with which the first separating membrane chamber, the first chamber portion and a channel therebetween are filled, in order to transfer a pressure to the measuring membrane; wherein the pressure sensor is specified for a temperature range between a minimum temperature and a maximum temperature, as well as for a pressure range.

Abstract: The invention relates to a capacitive pressure sensor and a method for fabricating thereof. The capacitive pressure sensor comprises a cover, a plurality of first electrode, a substrate and a plurality of second electrode. The cover owns an upper wall and a plurality of side walls. The plurality of first electrode is disposed on the inside of the upper wall of the cover. The side walls of the cover are connected to the substrate to form a space. The plurality of second electrode is disposed on the substrate. The plurality of first electrode and the plurality of second electrode are both in the space. In the invention, the material for cover, the plurality of first electrodes and the substrate are all flexible polymeric material.

Abstract: Disclosed is a method for measuring pressure in a container (1) filled or capable of being filled, using a pressure sensor (6) and a control unit (5). The filling or emptying is carried out under the control of the control unit (5) which receives as input signal, in addition to the pressure value (Ps) measured by the pressure sensor (6), a switching state (8) of a valve (4) controlled to fill or empty the container (1).

Abstract: A pressure sensor assembly for fitting within the valve stem of a vehicle tire comprises a substrate assembly defining a plurality of holes; a pressure sensor and a temperature compensation sensor mounted to the substrate assembly, each sensor including a corrugated deflectable membrane defining a first chamber and a cap mounted to the membrane to form a second chamber; and a cover configured to engage with the pressure sensor and the temperature compensation sensor to define an active chamber and a reference chamber respectively, the active chamber being exposed to tire pressure when the pressure sensor assembly is fitted within the valve stem whereas the reference chamber is sealed from tire pressure.

Abstract: A pressure sensing device comprising a base element for fastening the pressure sensing device provided with a connecting duct for feeding a pressurized fluid. The pressure sensing device has a support member that extends along a plugging direction and is fitted with a plug-in connector section configured to be plugged into a complementary plug-in connector. The support member is connected to the base and is equipped with a pressure duct that is connected to the connecting duct, and encompasses a receiving hole which extends perpendicular to the plugging direction and communicates with the pressure duct. The pressure sensing device includes a pressure sensor element that is inserted into the receiving hole such that one of the surfaces of the pressure sensor element is exposed to pressure from the pressure duct, and is connected to contact elements for transmitting signals.

Abstract: A biological fluid device (703) comprises a pressure sensor (702), which is arranged on the device. The pressure sensor comprises a compressible container, the compression of which is indicative of the pressure, and is capable of wireless communication.

Abstract: The invention discloses a trabecular stent and methods for treating glaucoma. The stent may incorporate an intraocular pressure sensor comprising a compressible element that is implanted inside an anterior chamber of an eye, wherein at least one external dimension of the element correlates with intraocular pressure. In some embodiments, the sensor may be coupled to the stent. Also disclosed are methods of delivery of the stent and the sensor to the eye.

Abstract: A pressure sensor assembly for fitting within the valve stem of a vehicle tire comprises a substrate assembly defining a plurality of holes; a pressure sensor and a temperature compensation sensor mounted to the substrate assembly, each sensor including a corrugated deflectable membrane defining a first chamber and a cap mounted to the membrane to form a second chamber; and a cover configured to engage with the pressure sensor and the temperature compensation sensor to define an active chamber and a reference chamber respectively, the active chamber being exposed to tire pressure when the pressure sensor assembly is fitted within the valve stem whereas the reference chamber is sealed from tire pressure.

Abstract: A single pressure sensing capsule has a reference pressure ported to the rear side of a silicon sensing die. The front side of the silicon sensing die receives a main pressure at another port. The silicon sensing die contains a full Wheatstone bridge on one of the surfaces and within the active area designated as the diaphragm area. Thus, the difference of the main and reference pressure results in the sensor providing an output equivalent to the differential pressure, namely the main pressure minus the reference pressure which is the stress induced in a sensing diaphragm. In any event, the reference pressure or main pressure may be derived from a pump pressure which is being monitored. The pump pressure output is subjected to a pump ripple or a sinusoidally varying pressure. In order to compensate for pump ripple, one employs a coiled tube. The tube length is selected to suppress the pump ripple as applied to the sensor die.

Abstract: A pressure sensing device comprising a base element for fastening the pressure sensing device provided with a connecting duct for feeding a pressurized fluid. The pressure sensing device has a support member that extends along a plugging direction and is fitted with a plug-in connector section configured to be plugged into a complementary plug-in connector. The support member is connected to the base and is equipped with a pressure duct that is connected to the connecting duct, and encompasses a receiving hole which extends perpendicular to the plugging direction and communicates with the pressure duct. The pressure sensing device includes a pressure sensor element that is inserted into the receiving hole such that one of the surfaces of the pressure sensor element is exposed to pressure from the pressure duct, and is connected to contact elements for transmitting signals.

Abstract: A pressure sensor assembly is provided for fitting within the valve stem of a vehicle tire. The assembly comprises a substrate assembly defining a plurality of holes. A pressure sensor and a temperature compensation sensor are mounted to the substrate assembly. Each sensor includes a deflectable membrane defining a first chamber and a cap mounted to the membrane to form a second chamber. A cover is provided for engaging with the pressure sensor and the temperature compensation sensor to define an active chamber and reference chamber respectively. The active chamber is exposed to tire pressure when the pressure sensor assembly is fitted within the valve stem whereas the reference chamber is sealed from tire pressure.

Abstract: A pressure sensor is provided having a substrate assembly having a first substrate bonded to a second substrate via an intermediate bonding layer so as to define sealed channels in the first substrate, a sealed reference chamber on said first substrate and having the sealed channels, and an apertured chamber on said first substrate and covering the sealed reference chamber.

Abstract: The present invention relates to a pressure sensor. The pressure sensor includes a substrate assembly. The substrate assembly defines sealed channels and includes a conductive layer. A conductive membrane extends from the substrate assembly and is spaced from the conductive layer to form a sealed reference chamber. A cap defines apertures. The cap extends from the substrate assembly to cover the membrane and thereby form an apertured chamber.

Abstract: The inventive pressure transmitting connector, in particular for an endoscopy system includes a fluid transporting channel, a blind compartment which opens towards the transport channels by a pipe and closed by a membrane which is deformable according to a pressure in the transport channels and a device for transmitting a representative quantity of the pressure in the transport channel according to the membrane deformation. The transport channel, the pipe and the blind compartment are embodied in the same rigid part to which the membrane is attached. In a preferred embodiment, the membrane simultaneously closes the blind compartment and a pressure transmitting chamber attached to the rigid part.

Abstract: A pressure sensor assembly is provided for fitting within the valve stem of a vehicle tire. The assembly comprises a substrate assembly defining a plurality of holes. A pressure sensor and a temperature compensation sensor are mounted to the substrate assembly. Each sensor includes a deflectable membrane defining a first chamber and a cap mounted to the membrane to form a second chamber. A cover is provided for engaging with the pressure sensor and the temperature compensation sensor to define an active chamber and reference chamber respectively. The active chamber is exposed to tire pressure when the pressure sensor assembly is fitted within the valve stem whereas the reference chamber is sealed from tire pressure.

Abstract: Methods and apparatus for sensing pressure are disclosed. One disclosed pressure measuring device comprises a pressure transmission catheter including a stem portion and a sheath fixed to the stem portion. The disclosed sheath comprises a wall defining a cavity that is in fluid communication with a stem lumen defined by the stem portion. The disclosed sheath has a first transverse extent and a second transverse extent that is different from the first transverse extent.

Abstract: A pressure sensor for sensing a fluid pressure in harsh environments such as the air pressure in a tire formed on a wafer substrate. Associated circuitry deposited in CMOS layers on the wafer substrate has a conductive layer at least partially overlying the associated circuitry, the conductive layer forming a first electrode of the capacitative sensor. A conductive membrane at least partially overlies the conductive layer, and is spaced from it to form a second electrode of the capacitative sensor. The conductive membrane separates fluid at a reference pressure and fluid at the pressure to be sensed such that the associated circuitry is configured to convert the deflection of the conductive membrane into an output signal indicative of the fluid pressure. The conductive membrane is at least partially formed from a ceramic material to provide corrosion and wear resistance.

Abstract: A pressure sensor (30) for environments with wide ranging temperatures such as vehicle tires. The sensor has a conductive sensor membrane (53) exposed to the fluid pressure to be sensed, and a similarly conductive reference membrane subject to a predetermined pressure difference. Both membranes are connected to circuitry that converts the deflection in the sensor membrane into an output signal indicative of the pressure difference across the sensor membrane, and converts the deflection of the reference membrane into a thermal expansion compensation value used to adjust the output signal in response to temperature variations in the pressure sensor's environment.

Abstract: A sensor assembly includes a stainless steel tubular housing. Within the housing is a polyetheretherketone tube and a sensor. An optical fiber joins the sensor to a transmission cable and is fixedly positioned within the tube. A first end of the housing includes a pressure transmission device or bellows and the second end of the housing is crimped about the tube to fixedly position the tube and the sensor within the housing. The sensor assembly is positioned within a channel of a gasket to obtain pressure data from a combustion chamber. This abstract is provided to comply with the rules requiring an abstract that will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims.

Abstract: A method for detecting a high pressure condition within a high voltage vacuum device includes detecting the position of a movable structure such as a bellows or flexible diaphragm. The position at high pressures can be detected optically by the interruption or reflection of light beams, or electrically by sensing contact closure or deflection via strain gauges. Electrical sensing is provided by microcircuits that are operated at high voltage device potentials, transmitting pressure information via RF or optical signals.

Abstract: A sensor is provided for a fluid system having a tank and a source of pressurized fluid. The sensor has a sensor body enclosing a sensor element that is configured to sense a parameter of the pressurized fluid. The sensor also has a first passageway configured to fluidly communicate the sensor element with the pressurized fluid and a first sealing interface configured to seal the first passageway. The sensor further has a second passageway configured to allow fluid that has leaked past the first sealing interface to drain to the tank.

Abstract: A pressure sensor is provided having a chamber partially defined by a flexible membrane which is less than three microns thick, exposed to fluid pressure and is configured to deflect from a reference position due to changes in the fluid pressure, and associated circuitry for converting the deflection of the flexible membrane into an output signal indicative of the fluid pressure.

Abstract: A pressure sensor for sensing a fluid pressure in a high acceleration environment. The sensor has a chamber partially defined by a non-planar membrane, the chamber containing a fluid at a reference pressure, such that the non-planar membrane deflects due to pressure differentials between the reference pressure and the fluid pressure. The deflection is converted into an output signal indicative of the fluid pressure by associated circuitry. By keeping the area of the membrane exposed to the fluid in the chamber to less than 0.1 grams, the acceleration forces have minimal affect on the amount that membrane flexes.

Abstract: A pressure sensor for sensing a fluid pressure in harsh environments such as the air pressure in a tire formed on a wafer substrate. Associated circuitry deposited in CMOS layers on the wafer substrate has a conductive layer at least partially overlying the associated circuitry, the conductive layer forming a first electrode of the capacitative sensor. A conductive membrane at least partially overlies the conductive layer, and is spaced from it to form a second electrode of the capacitative sensor. The conductive membrane has one side exposed to the fluid pressure and the conductive layer is sealed from the fluid pressure by the conductive membrane such that, the associated circuitry converts the deflection of the conductive membrane into an output signal indicative of the fluid pressure. The conductive membrane is at least partially formed from a ceramic material to provide corrosion and wear resistance.

Abstract: A pressure measuring apparatus includes a gage that is at least partially imbedded within a flexible elastomeric member disposed within an interior cavity of a device housing. A shock resistant member into which the gage is inserted permits fluid interconnection between the interior of the gage having a contained movement mechanism that is responsive to fluid pressure changes and a fluid source, such as an inflatable blood pressure cuff and further provides shock and/or impact resistance for a contained movement mechanism. Additional impact/shock absorption is provided by exterior features of the apparatus, including a peripheral bumper having a plurality of raised spring-like protrusions, and rubberized and contoured features of the device housing.

Abstract: A pressure module is provided which comprises a capsule having a cavity formed therein, and a pressure transducer disposed within the cavity of the capsule. A feedthrough pin, fixedly coupled to the capsule, extends into the capsule and is electronically coupled to the pressure transducer.

Abstract: A pressure sensor (30) for environments with wide ranging temperature variations such as vehicle tires. The sensor has a sensor membrane (53) exposed to the fluid pressure to be sensed, and a reference membrane subject to a predetermined pressure difference. Both membranes are conductive and connected to circuitry that converts the deflection in the sensor membrane into an output signal indicative of the pressure difference across the sensor membrane, and converts the deflection of the reference membrane into a temperature compensation value used to adjust the output signal into a temperature compensated signal indicate of the fluid pressure to be sensed.

Abstract: A pressure capsule embedded in a pacemaker lead to monitor intracardiac chamber pressure is described. This pressure monitor capsule provides highly accurate pressure readings while insuring a high integrity seal against bodily fluids and tissue growth. The capsule is intended to be embedded into a pacemaker cardiac lead or a catheter with the distal (Tip) isolation diaphragm sensing pressure, coupling the pressure through an air column to a protected sensing MEMS device and providing a secure fluid seal to the lead walls. The proximal (Back) end of the capsule provides the electrical interface through the lead to the pacemaker pulse generator.

Abstract: A pressure sensor (30) for sensing a fluid pressure in harsh environments such as the air pressure in a tire, by using a chamber (58) partially defined by a flexible membrane (50), the chamber (58) containing a fluid at a reference pressure, such that the flexible membrane (50) deflects due to pressure differentials between the reference pressure and the fluid pressure; and, associated circuitry (34) for converting the deflection of the flexible membrane (50) into an output signal indicative of the fluid pressure; wherein, the membrane (50) is at least partially formed from a metal ceramic material. Metal ceramics can be deposited as a thin membrane with sufficient flexibility for sensing pressure while providing corrosion and wear resistance. Furthermore, these materials are generally well suited to micro fabrication processes and electrically conductive so they can be used in capacitative and resistive type pressure sensors.

Abstract: A pressure sensor (30) for harsh environments such as vehicle tires, the sensor having a chamber (58) partially defined by a flexible membrane (50), the chamber containing a fluid at a reference pressure. In use, the flexible membrane (50) deflects due to pressure differentials between the reference pressure and the fluid pressure, so that, associated circuitry (34) can convert the deflection of the flexible membrane (50) into an output signal indicative of the fluid pressure. The sensor is a MEMS device whereby the recess, the flexible membrane and the associated circuitry are formed using lithographically masked etching and deposition techniques. MEMS fabrication techniques can produce the sensor in such high volumes that the unit cost of each sensor is very low. The MEMS sensor is so small that it can be installed in very restricted areas such as the stem of the tire valve.

Abstract: A flow control unit having a housing with a valve chamber. The valve chamber has an inlet and an outlet. The inlet of the valve chamber is placed in communication with the process circuit. A valve member is carried within the valve chamber. The valve member has an open position for allowing flow from the inlet of the valve chamber to the outlet of the valve chamber, and a closed position for preventing flow through the valve chamber. A pressure cell is disposed adjacent the outlet of the valve chamber. A closed pressure circuit is defined from the valve inlet, the valve chamber, and the valve outlet. A pressure sensor is disposed in the pressure cell and traverses the circuit at the outlet for measuring the pressure of the process circuit communicated through the closed pressure circuit when the valve member is in the open position.

Abstract: A pressure sensor (30) for harsh environments such as vehicle tires, the sensor having a chamber (58) partially defined by a flexible membrane (50), the chamber (58) containing a fluid at a reference pressure. In use, the flexible membrane (50) deflects due to pressure differentials between the reference pressure and the fluid pressure, so that, associated circuitry (34) can convert the deflection of the flexible membrane into an output signal indicative of the fluid pressure. The sensor is a MEMS device whereby the recess, the flexible membrane and the associated circuitry are formed using lithographically masked etching and deposition techniques. MEMS fabrication techniques can produce the sensor in such high volumes that the unit cost of each sensor is very low. The MEMS sensor is so small that it can be installed in very restricted areas such as the stem of the tire valve.

Abstract: A pressure sensor (30) for harsh environments such as vehicle tires, formed from a chamber (58) partially defined by a flexible membrane (50), the chamber (58) containing a fluid at a reference pressure. In use, the flexible membrane (50) deflects from any pressure difference between the reference pressure and the fluid pressure. The membrane (50) being at least partially formed from conductive material so that associated circuitry (34) converts the deflection of the flexible membrane (50) into an output signal indicative of the fluid pressure. The flexible membrane is less than 3 microns thick to allow the use of a high yield strength membrane material. A thinner membrane also allows the area of the membrane to be reduced. Reducing the area of the membrane reduces the power consumption and the overall size of the sensor. A high yield strength material is better able to withstand the extreme conditions within the tire and a compact design can be installed in restricted spaces such as the valve stem.

Abstract: A pressure sensor that compensates for variations in temperature by having first (53) and second (51) chambers with first and second respective flexible membranes. The first and second flexible membranes deflect in response to pressure differences within the first and second chambers respectively. The first membrane is exposed to the fluid pressure (66) to be measured, such as the air pressure in a tire. The second membrane sealed from the fluid pressure, and, associated circuitry converts the deflection of the first flexible membrane into an output signal related to the fluid pressure, and converts the deflection of the second membrane into an adjustment of the output signal to compensate for the temperature of the sensor. By sealing the second chamber from the tire pressure, the deflection of the second membrane can be determined as a function of temperature. This can be used to calibrate the output signal from the first chamber to remove the effects of temperature variation.

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 pressure transmitter for transferring a pressure from a pressure prevailing in a first medium onto a second medium includes a pressure chamber between a platform and a dividing membrane, wherein the pressure chamber is fillable with the second medium and has a pressure chamber opening, through which the pressure can be transmitted by means of the second medium to a pressure measurement cell. The pressure transmitter includes a sensor for monitoring a material property of the second medium, preferably a conductivity sensor with at least one electrode, which sensor can detect contaminants in the second medium from the first medium following a rupture of the dividing membrane on the basis of changes in the monitored material property. The sensor is in flow connection with the pressure chamber by way of the pressure chamber opening.

Abstract: A flow control unit having a housing with a valve chamber. The valve chamber has an inlet and an outlet. The inlet of the valve chamber is placed in communication with the process circuit. A valve member is carried within the valve chamber. The valve member has an open position for allowing flow from the inlet of the valve chamber to the outlet of the valve chamber, and a closed position for preventing flow through the valve chamber. A pressure cell is disposed adjacent the outlet of the valve chamber. A closed pressure circuit is defined from the valve inlet, the valve chamber, and the valve outlet. A pressure sensor is disposed in the pressure cell and traverses the circuit at the outlet for measuring the pressure of the process circuit communicated through the closed pressure circuit when the valve member is in the open position.

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: The present invention provides a fast and accurate method of measuring the vacuum pressure in a sealed glass vial or other electrically non-conductive vessel. In the method the vial or vessel to be tested is placed between a pair of electrodes. The gas contained within the vial or vessel is ionized by applying a high frequency, high voltage potential across the electrodes. The voltage is progressively decreased once ionization has occurred and the termination of ionization is detected by registering either the sudden drop in electrode current or the termination of light emission from the vial. The gas pressure within the vial or vessel is derived as a function of the electrode voltage at the point at which ionization terminates.

Abstract: A pressure measuring structure of a hot air generator is provided.

Abstract: An inflatable sleeve for a blood pressure measuring apparatus includes a socket which is capable of receiving an engagement portion of a gage housing thereby permitting direct attachment to the sleeve and permitting fluid interconnection between the interior of the inflatable sleeve and the interior of the housing without requiring any hoses or tubing there between. The sleeve includes an artery index marker which permits the sleeve to be properly aligned on an appropriate limb of the patient.

Abstract: A sensor capsule suitable for use in an industrial process fluid transmitter. The sensor capsule includes a block that has a sensor mounting hole. The block includes two half-blocks joined along mating surfaces passing lengthwise through the sensor mounting hole. A sensor has a sensor neck passing through the sensor mounting hole. The sensor neck is sealed to the sensor mounting hole.

Abstract: This pressure gauge comprises a mounting section connected to a joint provided partway along a pipeline, and a measurement section provided on the mounting section, and in which the upwards movement of an actuator rod causes a rotation of a needle. In the mounting section, a concave section is provided with a base which interconnects with the inside of the pipeline, and inside this concave section is provided a diaphragm with a closed base, with an outer surface comprising a bellows section formed as a concertina shape, and with a central aperture for housing the tip of the actuator rod, and the pressure of fluid within the pipeline acts upon the base of the diaphragm compressing the diaphragm. At the tip of the actuator rod housed within the housing aperture is installed a protective cap which is constructed from polytetrafluoroethylene resin or a vinyl chloride or the like with excellent chemical resistance.