73results about How to "Improve pressure measurement accuracy" patented technology

A system for determining pressure change in a liquid flowing in a tube of an elastic material has a sensor head having a slot and a pair of piezoelectric elements mounted in opposing walls of said slot between which the tube is placed in contact with the opposing elements. An electronic circuit generates periodic bursts of electro-mechanical energy from one of the elements that is transmitted through the tube to be received by the other element to be converted to an electrical signal from which is measured the travel time value of the energy through the tube and liquid therein and the amplitude value of the received signal which values are compared to at least one of base line travel time and amplitude values to determine a change of pressure of the liquid flowing in the tube.

An arrangement for improving an accuracy of a pressure measurement made of a breathing gas including drops of water or humidity flowing along a flow channel is disclosed herein. The arrangement includes at least one pressure measuring channel to transmit a pressure of the breathing gas flowing along the flow channel to a measuring device to make the pressure measurement. The pressure measuring channel is equipped with a capillary material enabling capillary suctioning of water. Also a flow sensor for a flow rate measurement of a breathing gas including drops of water or humidity is provided.

The invention discloses a spring performance automatic testing device and a method of improving testing accuracy. A tested spring is micro pressure spring which is used in a geophone. The automatic testing device is composed of three parts, namely a mechanism structure, a transmission structure and a testing and controlling circuit. A stepping motor and a linear guide rail are vertically installed, and a pressure measurement module is horizontally installed. When a slider on the linear guide rail is driven by the stepping motor to vertically reciprocate, the slider drives a circular rotating disc to achieve automatic placement of the batch of the springs to be tested and automatic testing of the performance of the springs to be tested. The spring is compressed to the preset position by using a pressure plate which is connected with a dual closed-loop controlling driving slider, current elastic values are tested in real time by the pressure measurement module, and thereby the elastic value and stiffness factor of the spring which is at the random position within the elastic range can be accurately measured. The spring performance automatic testing device has the advantages of being high in accuracy, good in repeatability and capable of obviously improving measurement accuracy of the geophone.

The invention discloses a high-precision pressure measuring system with variable reference pressure. The high-precision pressure measuring system is mainly used for wind tunnel experiment measurement,and belongs to the technical field of gas pressure measurement. The high-precision pressure measuring system provides reference pressure Pref which is close to measured pressure P through a referencepressure cavity, the reference pressure Pref is measured by means of a high-precision steady-state pressure meter, and a difference value dP between P and Pref is measured by using a small-measuring-range dynamic differential pressure sensor, namely, the measured pressure is decomposed into stable reference pressure and dynamic pressure with a small absolute value, and the stable reference pressure and the dynamic pressure are measured by means of appropriate sensors and then are re-synthesized. The high-precision pressure measuring system can satisfy requirements for response frequency of dynamic pressure measurement, has high measuring precision, solves the problem of low measurement precision of a high-frequency dynamic pressure sensor, and can adjust the reference pressure to adapt toa wide measuring range scope, so as to reduce the quantity demand of the sensors.

The invention belongs to the field of pressure measurement, particularly to a digital temperature compensation system and a method. The temperature compensation system includes a constant-current source (1), a pressure sensing module (3), a pressure signal amplifier (5), a temperature signal amplifier (8), a multiplexing switch (9), an A/D conversion module (6) and a processor (7). The method includes steps including system calibration, storage of system temperature calibration results, and the measurement temperature compensation. According to the invention, in the digital temperature compensation system, a temperature compensation resistor is additionally arranged at a pressure sensor through the design of the pressure sensing module to amplify the temperature characteristic of the pressure sensor and realize the automatic temperature compensation, so that the installation and maintenance are convenient, and the function of serving as the pressure sensor and the temperature sensor at the same time are realized. The digital temperature compensation method provided by the invention realizes the automatic temperature compensation at any temperature and any pressure, has higher measuring accuracy, improves the pressure measuring accuracy, and has the full range error smaller than 0.02% or lager than minus 0.02%.

The invention discloses a micro mud floating electronic pressure gauge, a working method thereof, and a pressure measurement device, relates to the field of oil and gas extraction, and aims to provide a device for measuring underground pressure and temperature in the mud drilling process in real time, and a working method thereof. The technical key point is that: a button cell, a singlechip with acquisition software, a circuit board, a connection block, and a pressure chip are stacked in a shell sequentially from bottom to top; the shell is a cylindrical shell of which the upper and lower ends are provided with openings, and the interior and the exterior of the shell are isolated by isolation protective adhesive; the pressure gauge acquires temperature and pressure information intermittently under a well; and the pressure measurement device comprises the pressure gauge, a data loading system, and a pressure and temperature calibrating device. The pressure gauge is as small as drill cuttings, so the pressure gauge can float in mud and move along with mud, measure pressure timely and recover data, and does not influence the drill construction.

The invention relates to the technical field of pressure sensors and particularly relates to a wide-range high-precision double film-integrated capacitive pressure sensor and a manufacturing method. The wide-range high-precision double film-integrated capacitive pressure sensor comprises a glass substrate; a first shallow groove and a second shallow groove are arranged in the glass substrate; the first shallow groove and the second shallow groove are communicated through a thin groove; the center position of the second shallow groove is provided with a shallow groove through hole; the shallow groove through hole extends to the bottom surface of the glass substrate from the bottom surface of the second shallow groove; the first shallow groove is provided with a capacitor C1 capable of measuring a low pressure difference; the second shallow groove is provided with a capacitor C2 capable of measuring a high pressure difference; the capacitor C1 capable of measuring the low pressure difference comprises a bottom electrode plate and a thin pressure sensitive film; the capacitor C2 capable of measuring the high pressure difference comprises a thick pressure sensitive film and a top electrode plate; the shallow groove through hole and the capacitor C1 capable of measuring the low pressure difference are arranged correspondingly; and the shallow groove through hole and the capacitor C2 capable of measuring the high pressure difference are arranged correspondingly. Through the capacitor C1 capable of measuring the low pressure difference and the capacitor C2 capable of measuring the high pressure difference, high-precision pressure measurement in a low pressure section and a high pressure section can be realized respectively.

The present invention discloses a stabilizing device used for fixing a detonation pressure sensor. The stabilizing device comprises a detonation pressure sensor stabilizer and a coaxial cable stabilizer, and the detonation pressure sensor stabilizer is a cylinder equipped with the large and small diameter stepped center holes matching an outer circle of a detonation pressure sensor body. The outer cylindrical surface of a circle body is equipped with the outer screw threads, and the end head is equipped with a concave edge bench. The large diameter center hole is equipped with the inner screw threads, and the outer cylindrical surface corresponding to the middle part of the large diameter center hole is symmetrically equipped with the installing holes communicated with the large diameter center hole. The coaxial cable stabilizer is a stepped cylinder equipped with an internal center hole and the external small, medium and large diameters, wherein the outer cylindrical surface of a small diameter cylinder is equipped with the outer screw threads, the end face is equipped with a counter bore communicated with the center hole. According to the present invention, the measurement data deviation caused by the instability of the sensor and a measurement error caused by the swinging or loosening of a coaxial cable are avoided effectively, thereby guaranteeing the accurate measurement of the detonation pressure sensor to a detonation wave.

The invention provides a capillary tube pressure measuring device, comprising a singlechip system, a current-to-voltage circuit, an A/D conversion circuit, a signal processing system, a display circuit and a serial communication circuit, wherein the singlechip system controls the whole machine; the current-to-voltage circuit converts input pressure current signals into voltage signals; an input end of the A/D conversion circuit is connected with the current-to-voltage circuit and the singlechip system; a circuit of the signal processing system is connected with the singlechip system; an input end of the display circuit is connected with the singlechip system; and the serial communication circuit is connected with the singlechip system. The pressure measuring device adopts the singlechip system to accomplish the data acquisition of pressure and temperature; the signal processing system realizes complicated iterative algorithm, thereby improving the precision and execution efficiency of the system; a communication interface not only has the serial communication between the signal processing system and an external computer, but also has the data transmission between a singlechip and the display circuit. The pressure measuring device has the advantages of small volume, convenience for carrying, high pressure measuring precision, accurate and rapid measured data, real-time monitoring and display, etc., which can be used for monitoring the pressure in oil-gas wells.

The invention provides an airborne scramjet pressure measurement system, which mainly includes an electronic pressure scanning valve, a pressure acquisition control module, a back pressure device and an absolute pressure sensor; the back pressure device provides reference pressure for the electronic pressure scanning valves 7 and 8 The absolute pressure sensor collects the pressure of the back pressure device, and the output signal of the electronic pressure scanning valve is sent to the pressure acquisition control module; the back pressure device is composed of an absolute pressure sensor interface, a back pressure device barrel and an impermeable steel pipe; the back pressure device barrel The inside is sealed with a local atmospheric pressure or evacuated; one end of the absolute pressure sensor interface is connected to the back pressure device cylinder, and the other end is connected to the absolute pressure sensor; one end of the stainless steel tube is connected to the back pressure device cylinder, and the other end is connected to the electronic pressure scanner through the pressure measuring pipeline valve. The invention is small in volume, light in weight and high in precision, helps to increase the proportion of payload in the aircraft structure, and provides an effective means of pressure measurement for hypersonic autonomous flight.

Provided is a method for measuring the pressure of a constant-volume quick inflation/deflation air cavity. In the constant-volume quick inflation/deflation process, gas mass flow and pressure data of an entrance of a container are detected in real time, the obtained data through detection is subjected to the averaging processing, and the pressure value of the inside of the container is obtained in the mode that the obtained data is substituted to the calculation formula of the pressure in the container in the inflation or deflation process. The method is good in realizability, and can be applied to occasions where pressure in the container needs to be accurately measured online in the constant-volume quick inflation/deflation process.

The invention discloses a non-intrusive pressure detection method and measurement system based on time delay intervals of adjacent longitudinal waves. According to the invention, the time delay intervals (including those between critical reflection longitudinal waves and first reflection longitudinal waves and those between adjacent reflection longitudinal waves) between adjacent longitudinal waves are selected as measurement parameters; a pressure measurement model of relation between pressure in a container and the time delay intervals between the adjacent longitudinal waves is established by utilizing ultrasonic wave acoustic elastic effect; and estimation of container pressure can be realized through measurement of the time delay intervals. Transit time of a critical refraction longitudinal wave and transit time of the reflection longitudinal waves generated under one excitation pulse are measured at the same time by adopting programmable shielding window technology and a TDC and the time delay intervals of the adjacent longitudinal waves can be obtained through calculation. The method provided by the invention can eliminate influence due to inconsistency of ultrasonic wave probe oscillation starting time and inconsistency of fixed characteristics of a coupling agent, an ultrasonic wave excitation and receiving circuit and a probe and pressure measurement precision can be improved.

The invention discloses a device and a method for measuring pressure intensity of gas inside microspheres. The method includes: adopting a corrugated-pipe-type crushing mechanism to crush a to-be-measured microsphere and a calibration sphere in a vacuum shell; through air pressure change of the vacuum shell before and after crushing, calibrating volume of the vacuum shell, and accurately measuringpressure intensity of gas inside the microspheres. The device and the method are suitable for precision measuring of pressure intensity of gas inside large-diameter-range microspheres having no requirement on transparency and composition of microsphere shell layers and microspheres with adsorptive gas.

The invention belongs to the field of ultrahigh pressure detection and relates to a pressure detection method based on a metastable phase rare-earth nickel-based oxide. According to the pressure detection method, a rare-earth nickel-based oxide with a thermodynamic metastable phase structure is used as a pressure sensitive material in a pressure detector; and pressure measurement in a high-pressure and ultrahigh-pressure spectral range is realized by utilizing a characteristic that the rare-earth nickel-based oxide changes sensitively along with pressure in the high-pressure and ultrahigh-pressure range and the relation of the change of resistivity and a resistance temperature coefficient along with pressure. Compared with previous pressure measuring methods, the method can realize pressure measurement in the spectral range, and realize the cross validation of pressure measurement in the high-pressure and ultrahigh-pressure range through the comprehensive characterization of the resistivity and a resistance temperature change rate, thereby greatly improving pressure measurement precision in the high-pressure range. The method of the invention can be further applied to the aspects of high-pressure detection, deep sea pressure measurement, geological pressure measurement and the like.

Devices and corresponding methods are provided to operate a hot cathode ionization pressure gauge (HCIG). A transistor circuit can be configured to pass the electron emission current with low input impedance and to control cathode bias voltage. Emission current and cathode bias voltage can be controlled independently of each other, without a servo settling time. HCIGs can be calibrated with respect to leakage current.

The invention discloses a digital wide-range ultra-high precision coil shaper. The digital wide-range ultra-high precision coil shaper comprises a mechanical part and a hydraulic control system for controlling the mechanical part. The digital wide-range ultra-high precision coil shaper has the advantages of being wide in pressure control range and high in pressure control precision. Through a position detecting device which is matched with a photoelectric protector, the position measurement of a sliding block can be conducted by redundancy control, working safety of the device is improved, and pressure measurement accuracy can be improved by using a plurality of force sensors arranged in a triangle.

The invention provides a vibrating wire type pressure sensor comprising a shell, a stress membrane, a force transmission piston, a piston cylinder body, a vibrating wire, a vibrating wire clamping device, a magnetic coil and a force transmission piston. The stress membrane is a circular membrane; a dowel bar is arranged in the center of one side of the stress membrane and a convex block is arranged in the center of the other side of the stress membrane; and a stress membrane shell with the same shape as the shell is arranged outside the stress membrane. The two ends of the stress membrane shell are connected with the shell and the piston cylinder body respectively. A hydraulic cavity communicated with the piston cylinder body is formed in the force transmission piston at one side of the dowel bar of the stress membrane; a free end of the dowel bar is directly connected with the force transmission piston through the bottom of the piston cylinder and the piston cavity. The cavity openingof the hydraulic cavity is formed in the outer end face of the force transmission piston; and a flexible contact film making contact with a measured object is arranged at the cavity opening of the hydraulic cavity in a sealed mode. The vibrating wire is fixed on the convex block. Therefore, the pressure measurement precision is improved; the performance is stable and reliable; and the vibrating wire type pressure sensor is suitable for measurement of liquid pressure, internal forces of concrete and rock-soil bodies, and an interface contact pressure.

A semiconductor pressure sensor includes a first substrate having a concave portion and an alignment mark at a main surface thereof, and a second substrate formed on the main surface of the first substrate and having a diaphragm provided to cover a space inside the concave portion of the first substrate and a gauge resistor provided on the diaphragm. The alignment mark is provided to be exposed from the second substrate. Accordingly, it is possible to obtain a semiconductor pressure sensor and a method of manufacturing the same with reduced production costs and with improved pressure measuring accuracy.