CN101551268A - Piezoelectric type infrasonic sensor capable of offsetting mechanical vibration signals - Google Patents
Piezoelectric type infrasonic sensor capable of offsetting mechanical vibration signals Download PDFInfo
- Publication number
- CN101551268A CN101551268A CNA2009100224529A CN200910022452A CN101551268A CN 101551268 A CN101551268 A CN 101551268A CN A2009100224529 A CNA2009100224529 A CN A2009100224529A CN 200910022452 A CN200910022452 A CN 200910022452A CN 101551268 A CN101551268 A CN 101551268A
- Authority
- CN
- China
- Prior art keywords
- metalfilmresistor
- connects
- sensing unit
- circuit
- socket
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Withdrawn
Links
Images
Landscapes
- Gyroscopes (AREA)
Abstract
The invention discloses a piezoelectric type infrasonic sensor that can offset mechanical vibration signals. The sensor comprises a shell, a piezoelectric sensing unit and a circuit board for amplifying filtering wave, wherein the piezoelectric sensing unit is provided with a first sensing unit and a second sensing unit, the structure and the mechanical vibration performance of which are the same, and the first sensing unit is used for measuring superposed signals of sound wave and mechanical vibration; the second sensing unit which has the same structure as the first sensing unit is used for measuring the mechanical vibration signals; the circuit board for amplifying filtering wave is fixed on a socket fixing board at the top of the shell and comprises a fronting differential amplifying circuit, a band-pass filtering circuit and a DC/DC converting circuit, high impedance voltage signals output by the first sensing unit and the second sensing unit are connected with the circuit board for amplifying filtering wave, the mechanical vibration signals are eliminated by signal offsetting, and only sound wave signals are amplified and output; and the output end of the fronting differential amplifying circuit is connected with the band-pass filtering circuit which outputs infrasonic sensing signals.
Description
Technical field
The present invention relates to a kind of infrasonic sensor, but be specifically related to a kind of piezoelectric infrasonic wave sensor of canceling mechanical oscillation.
Background technology
Infrasonic wave is because its frequency is very low, amplitude is decayed slowly in time, but long-distance communications.Utilize the infrasonic wave sensing technology, can measure the position at vapour-liquid, interface such as liquid-solid at a distance fast.The dynamic oil level of sonic method fast detecting oil well crude oil is all adopted basically in the oil field of countries in the world in the oil recovery production run, and determines that working fluid level position, down-hole is to realize efficient vital prerequisite of recovering the oil.In adopting the sonic well logging process, because the oil well working environment is more abominable, a large amount of corrosive gass is contained in the down-hole, measurement mechanism there is very large corrosive attack, cause the life-span of existing colloid encapsulation garden column casing shape piezoelectric sensor very low, and low, the poor signal to noise of this transducer sensitivity, its high impedance weak electric signal need be transferred in the other amplifying circuit by long lead and amplify, and this transmission course is interfered especially easily.And existing sonic sensor can't be eliminated the influence of mechanical vibration, and its output is the superposed signal of sound wave and mechanical vibration, when ground oil production equipment itself vibrates or wind-engaging carry and do the time spent, can cause and can't measure.
Summary of the invention
The objective of the invention is to overcome the shortcoming of above-mentioned prior art, the piezoelectric infrasonic wave sensor capable of canceling mechanical oscillation signal that a kind of mechanism is simple, highly sensitive, antijamming capability is strong is provided.
For achieving the above object, the technical solution used in the present invention is: comprise stainless steel casing, be provided with the sound wave input hole in the lower end of shell, the upper end of sound wave input hole is provided with the copper bottom crown of first sensing unit, the bottom crown of first sensing unit and shell electrically conducting, as public electrode, the upper end of the bottom crown of first sensing unit is provided with cover in first insulation, place the first stacked piezoelectric sheet in the cover in first insulation, the upper end of the first stacked piezoelectric sheet is connected with copper top crown, top crown and first only revolves insulating barrier and is connected, the first screw thread pressing plate is fixed in first upper end of only revolving dividing plate, and first centre of only revolving the dividing plate and the first screw thread pressing plate is provided with first fairlead; The upper end of the first screw thread pressing plate is second sensing unit, the copper bottom crown of second sensing unit is connected with shell, the bottom crown of second sensing unit and shell electrically conducting, as public electrode, the upper end of the bottom crown of second sensing unit is provided with cover in second insulation, be placed with the second stacked piezoelectric sheet in the cover in second insulation, the upper end of the second stacked piezoelectric sheet is connected with the second copper top crown, second top crown and second only revolves insulating barrier and is connected, the second screw thread pressing plate is fixed in second upper end of only revolving dividing plate, and second centre of only revolving the dividing plate and the second screw thread pressing plate is provided with second fairlead; The shell upper end is provided with the socket fixed head, the gang socket of socket fixed head, the amplification filtering circuit board is connected with the socket fixed head, the input end of the preposition differential amplifier circuit of amplification filtering circuit board connects the high impedance voltage signal of the first stacked piezoelectric sheet and the output of the second stacked piezoelectric sheet respectively, the output terminal of preposition differential amplifier circuit connects bandwidth-limited circuit, and the DC/DC translation circuit is given preposition differential amplifier circuit and bandwidth-limited circuit power supply; Arranged outside at shell has rubber gasket.
The high impedance voltage signal of first stacked piezoelectric sheet of the present invention and the output of the second stacked piezoelectric sheet meets the first input end IN1 and the second input end IN2 of socket J1 in the preposition differential amplifier circuit respectively, the first input end IN1 of socket J1 connects the normal phase input end of instrument amplifier U1, the second input end IN2 of socket J1 connects the inverting input of instrument amplifier U1, first pin of instrument amplifier U1 connect precision resistor P1 an end and with the intermediate regulations terminal shortcircuit, the 8th pin of another termination instrument amplifier U1 of precision resistor P1, negative supply the 4th pin of instrument amplifier U1 connects-the 5V power supply, positive supply the 7th pin of instrument amplifier U1 connects+the 5V power supply, the 5th pin of instrument amplifier U1 connects public ground, output terminal the 6th pin of instrument amplifier U1 is connected with the first polarity free capacitor C1, the other end of the first polarity free capacitor C1 connects the end of the second polarity free capacitor C2 and the first metalfilmresistor R1 respectively, the other end of the second polarity free capacitor C2 connects the normal phase input end of operational amplifier U2A and the end of the second metalfilmresistor R2 respectively, the output terminal of another termination operational amplifier U2A of the first metalfilmresistor R1, the public ground of another termination of the second metalfilmresistor R2, the inverting input of operational amplifier U2A connects the end of the 3rd metalfilmresistor R3 and the 4th metalfilmresistor R4 respectively, the output terminal of another termination operational amplifier U2A of the 3rd metalfilmresistor R3, the public ground of another termination of the 4th metalfilmresistor R4, the output terminal of operational amplifier U2A belongs to film resistance R5 with five metals and is connected, five metals belongs to the end that film resistance R5 meets the 6th metalfilmresistor R6 and the 3rd polarity free capacitor C3 respectively, the other end of the 6th metalfilmresistor R6 connects the normal phase input end of operational amplifier U2B and the end of the 4th polarity free capacitor C4 respectively, the output terminal of another termination operational amplifier U2B of the 3rd polarity free capacitor C3, the public ground of another termination of the 4th polarity free capacitor C4, the inverting input of operational amplifier U2B connects the end of the 7th metalfilmresistor R7 and the 8th metalfilmresistor R8 respectively, the output terminal of another termination operational amplifier U2B of the 7th metalfilmresistor R7, the public ground of another termination of the 8th metalfilmresistor R8, the output terminal of operational amplifier U2B is connected with the OUT end of the J2 of socket, the public ground of the GND termination of the J2 of socket, the VIN end of the J2 of socket and 0V end connect the power supply input first of the power module 5D5 of DC-DC translation circuit respectively as 5V power supply input end, two pins, second pin of the power module 5D5 of DC-DC translation circuit and the 5th pin export respectively with 5V power supply electrical isolation+5V and-5V voltage, give circuit supply, the 4th pin of the power module 5D5 of DC-DC translation circuit connects public ground.
The present invention utilizes two sensing units and differential amplifier circuit, has eliminated mechanical oscillation signal, only amplifies output sound wave transducing signal.Sensitive element and amplification filtering circuit package are in a metal construction, because the high impedance signal that is interfered especially easily of piezoelectric patches output does not remake long-distance transmissions, but be directly inputted to amplification filtering circuit in the same encapsulating structure, so greatly improved antijamming capability.The present invention is applicable to the infrasonic wave measurement, and frequency response range is 0.15Hz～30Hz, is enhanced at aspects such as signal to noise ratio (S/N ratio), sensitivity, transport property, high pressure resistant corrosion resistivities, has especially eliminated the influence of mechanical vibration.
Description of drawings
Fig. 1 is a structure principle chart of the present invention;
Fig. 2 is the block diagram of amplification filtering circuit 18 of the present invention;
Fig. 3 is the schematic diagram of amplification filtering circuit 18 of the present invention.
Embodiment
Below in conjunction with accompanying drawing structural principle of the present invention and principle of work are described in further detail.
With reference to Fig. 1, the present invention includes stainless steel casing 1, arranged outside at shell 1 has rubber gasket 2, be provided with sound wave input hole 3 in the lower end of shell 1, the upper end of sound wave input hole 3 is connected with the copper bottom crown 4 of first sensing unit, the bottom crown 4 and shell 1 electrically conducting of first sensing unit, as public electrode, the upper end of the bottom crown 4 of first sensing unit is provided with cover 5 in first insulation, be placed with the first stacked piezoelectric sheet 6 in the cover 5 in first insulation, the upper end of the first stacked piezoelectric sheet 6 is connected with copper top crown 7, top crown 7 and first only revolves insulating barrier 8 and is connected, the first screw thread pressing plate 9 is fixed in first upper end of only revolving dividing plate 8, and there is first fairlead 10 first centre of only revolving the dividing plate 8 and the first screw thread pressing plate 9; The upper end of the first screw thread pressing plate 9 is second sensing units, the copper bottom crown 11 of second sensing unit is connected with shell 1, the bottom crown 11 and shell 1 electrically conducting of second sensing unit, as public electrode, the upper end of the bottom crown 11 of second sensing unit is provided with cover 12 in second insulation, place the second stacked piezoelectric sheet 13 in the cover 12 in second insulation, the upper end of the second stacked piezoelectric sheet 13 is connected with the second copper top crown 14, second top crown 14 and second only revolves insulating barrier 15 and is connected, the second screw thread pressing plate 16 is fixed in second upper end of only revolving dividing plate 15, and there is second fairlead 17 second centre of only revolving the dividing plate 15 and the second screw thread pressing plate 16; The upper end of shell 1 is provided with socket fixed head 19,19 gang sockets 20 of socket fixed head, and amplification filtering circuit board 18 is connected with socket fixed head 19.The input end of the preposition differential amplifier circuit 21 of amplification filtering circuit board 18 connects the high impedance voltage signal of the first stacked piezoelectric sheet 6 and 13 outputs of the second stacked piezoelectric sheet respectively, the output terminal of preposition differential amplifier circuit 21 connects bandwidth-limited circuit 22, and DC/DC translation circuit 23 is given preposition differential amplifier circuit 21 and bandwidth-limited circuit 22 power supplies.
With reference to Fig. 2, Fig. 3, the input end of preposition differential amplifier circuit 21 connects the high impedance voltage signal of the stacked piezoelectric sheet output of two sensing units respectively, the output terminal of preposition differential amplifier circuit 21 connects bandwidth-limited circuit 22, and DC/DC translation circuit 23 is given preposition differential amplifier circuit 21 and bandwidth-limited circuit 22 power supplies.The high impedance voltage signal of the first stacked piezoelectric sheet (6) and the output of the second stacked piezoelectric sheet (13) meets the first input end IN1 and the second input end IN2 of socket J1 in the preposition differential amplifier circuit (21) respectively, the first input end IN1 of socket J1 connects the normal phase input end of instrument amplifier U1, the second input end IN2 of socket J1 connects the inverting input of instrument amplifier U1, first pin of instrument amplifier U1 connect precision resistor P1 an end and with the intermediate regulations terminal shortcircuit, the 8th pin of another termination instrument amplifier U1 of precision resistor P1, negative supply the 4th pin of instrument amplifier U1 connects-the 5V power supply, positive supply the 7th pin of instrument amplifier U1 connects+the 5V power supply, the 5th pin of instrument amplifier U1 connects public ground, output terminal the 6th pin of instrument amplifier U1 is connected with the first polarity free capacitor C1, the other end of the first polarity free capacitor C1 connects the end of the second polarity free capacitor C2 and the first metalfilmresistor R1 respectively, the other end of the second polarity free capacitor C2 connects the normal phase input end of operational amplifier U2A and the end of the second metalfilmresistor R2 respectively, the output terminal of another termination operational amplifier U2A of the first metalfilmresistor R1, the public ground of another termination of the second metalfilmresistor R2, the inverting input of operational amplifier U2A connects the end of the 3rd metalfilmresistor R3 and the 4th metalfilmresistor R4 respectively, the output terminal of another termination operational amplifier U2A of the 3rd metalfilmresistor R3, the public ground of another termination of the 4th metalfilmresistor R4, the output terminal of operational amplifier U2A belongs to film resistance R5 with five metals and is connected, five metals belongs to the end that film resistance R5 meets the 6th metalfilmresistor R6 and the 3rd polarity free capacitor C3 respectively, the other end of the 6th metalfilmresistor R6 connects the normal phase input end of operational amplifier U2B and the end of the 4th polarity free capacitor C4 respectively, the output terminal of another termination operational amplifier U2B of the 3rd polarity free capacitor C3, the public ground of another termination of the 4th polarity free capacitor C4, the inverting input of operational amplifier U2B connects the end of the 7th metalfilmresistor R7 and the 8th metalfilmresistor R8 respectively, the output terminal of another termination operational amplifier U2B of the 7th metalfilmresistor R7, the public ground of another termination of the 8th metalfilmresistor R8, the output terminal of operational amplifier U2B is connected with the OUT end of the J2 of socket (20), the public ground of the GND termination of the J2 of socket (20), the VIN end of the J2 of socket (20) and 0V end connect the power supply input first of the power module 5D5 of DC-DC translation circuit (23) respectively as 5V power supply input end, two pins, second pin of the power module 5D5 of DC-DC translation circuit (23) and the 5th pin export respectively with 5V power supply electrical isolation+5V and-5V voltage, give circuit supply, the 4th pin of the power module 5D5 of DC-DC translation circuit (23) connects public ground.
The present invention is input to the extremely low preposition differential amplifier circuit 21 of bias current with the high impedance weak electric signal of two groups of stacked piezoelectric sheet outputs, the output tape splicing pass filter circuit 22 of preposition differential amplifier circuit 21, DC component and the signal that is higher than 30Hz are filtered, and DC/DC translation circuit 23 is given preposition differential amplifier circuit 21 and bandwidth-limited circuit 22 power supplies.Utilize two sensing units and differential amplifier circuit, eliminated mechanical oscillation signal, only amplify output sound wave transducing signal.Sensitive element and amplification filtering circuit package are in a metal construction, because the high impedance signal that is interfered especially easily of piezoelectric patches output does not remake long-distance transmissions, but be directly inputted to amplification filtering circuit in the same encapsulating structure, so greatly improved antijamming capability.The voltage sensitivity of this sensor is directly proportional with the quantity of laminated piezoelectric sheet, and the quantity by the increase and decrease piezoelectric patches changes level of sensitivity eaily.The present invention is applicable to the infrasonic wave measurement, and frequency response range is 0.15Hz～30Hz, is enhanced at aspects such as signal to noise ratio (S/N ratio), sensitivity, transport property, high pressure resistant corrosion resistivities, has especially eliminated the influence of mechanical vibration.
Claims (3)
1, a kind of piezoelectric infrasonic wave sensor capable of canceling mechanical oscillation signal, comprise stainless steel casing (1), be provided with sound wave input hole (3) in the lower end of shell (1), it is characterized in that: the upper end of sound wave input hole (3) is provided with the copper bottom crown (4) of first sensing unit, bottom crown of first sensing unit (4) and shell (1) electrically conducting, as public electrode, the upper end of the bottom crown of first sensing unit (4) is provided with cover (5) in first insulation, place the first stacked piezoelectric sheet (6) in the cover (5) in first insulation, the upper end of the first stacked piezoelectric sheet (6) is connected with copper top crown (7), top crown (7) and first only revolves insulating barrier (8) and is connected, the first screw thread pressing plate (9) is fixed in first upper end of only revolving dividing plate (8), and first centre of only revolving the dividing plate (8) and the first screw thread pressing plate (9) is provided with first fairlead (10); The upper end of the first screw thread pressing plate (9) is second sensing unit, the copper bottom crown (11) of second sensing unit is connected with shell (1), bottom crown of second sensing unit (11) and shell (1) electrically conducting, as public electrode, the upper end of the bottom crown of second sensing unit (11) is provided with cover (12) in second insulation, be placed with the second stacked piezoelectric sheet (13) in the cover (12) in second insulation, the upper end of the second stacked piezoelectric sheet (13) is connected with the second copper top crown (14), second top crown (14) and second only revolves insulating barrier (15) and is connected, the second screw thread pressing plate (16) is fixed in second upper end of only revolving dividing plate (15), and second centre of only revolving the dividing plate (15) and the second screw thread pressing plate (16) is provided with second fairlead (17); The upper end of shell (1) is provided with socket fixed head (19), socket fixed head (19) gang socket (20), amplification filtering circuit board (18) is connected with socket fixed head (19), the input end of the preposition differential amplifier circuit (21) of amplification filtering circuit board (18) connects the high impedance voltage signal of the first stacked piezoelectric sheet (6) and the output of the second stacked piezoelectric sheet (13) respectively, the output terminal of preposition differential amplifier circuit (21) connects bandwidth-limited circuit (22), and DC/DC translation circuit (23) is given preposition differential amplifier circuit (21) and bandwidth-limited circuit (22) power supply.
2, piezoelectric infrasonic wave sensor capable of canceling mechanical oscillation signal according to claim 1 is characterized in that: the arranged outside of said shell (1) has rubber gasket (2).
3, piezoelectric infrasonic wave sensor capable of canceling mechanical oscillation signal according to claim 1, it is characterized in that: the high impedance voltage signal of said first stacked piezoelectric sheet (6) and the output of the second stacked piezoelectric sheet (13) meets the first input end IN1 and the second input end IN2 of socket J1 in the preposition differential amplifier circuit (21) respectively, the first input end IN1 of socket J1 connects the normal phase input end of instrument amplifier U1, the second input end IN2 of socket J1 connects the inverting input of instrument amplifier U1, first pin of instrument amplifier U1 connect precision resistor P1 an end and with the intermediate regulations terminal shortcircuit, the 8th pin of another termination instrument amplifier U1 of precision resistor P1, negative supply the 4th pin of instrument amplifier U1 connects-the 5V power supply, positive supply the 7th pin of instrument amplifier U1 connects+the 5V power supply, the 5th pin of instrument amplifier U1 connects public ground, output terminal the 6th pin of instrument amplifier U1 is connected with the first polarity free capacitor C1, the other end of the first polarity free capacitor C1 connects the end of the second polarity free capacitor C2 and the first metalfilmresistor R1 respectively, the other end of the second polarity free capacitor C2 connects the normal phase input end of operational amplifier U2A and the end of the second metalfilmresistor R2 respectively, the output terminal of another termination operational amplifier U2A of the first metalfilmresistor R1, the public ground of another termination of the second metalfilmresistor R2, the inverting input of operational amplifier U2A connects the end of the 3rd metalfilmresistor R3 and the 4th metalfilmresistor R4 respectively, the output terminal of another termination operational amplifier U2A of the 3rd metalfilmresistor R3, the public ground of another termination of the 4th metalfilmresistor R4, the output terminal of operational amplifier U2A belongs to film resistance R5 with five metals and is connected, five metals belongs to the end that film resistance R5 meets the 6th metalfilmresistor R6 and the 3rd polarity free capacitor C3 respectively, the other end of the 6th metalfilmresistor R6 connects the normal phase input end of operational amplifier U2B and the end of the 4th polarity free capacitor C4 respectively, the output terminal of another termination operational amplifier U2B of the 3rd polarity free capacitor C3, the public ground of another termination of the 4th polarity free capacitor C4, the inverting input of operational amplifier U2B connects the end of the 7th metalfilmresistor R7 and the 8th metalfilmresistor R8 respectively, the output terminal of another termination operational amplifier U2B of the 7th metalfilmresistor R7, the public ground of another termination of the 8th metalfilmresistor R8, the output terminal of operational amplifier U2B is connected with the OUT end of the J2 of socket (20), the public ground of the GND termination of the J2 of socket (20), the VIN end of the J2 of socket (20) and 0V end connect the power supply input first of the power module 5D5 of DC-DC translation circuit (23) respectively as 5V power supply input end, two pins, second pin of the power module 5D5 of DC-DC translation circuit (23) and the 5th pin export respectively with 5V power supply electrical isolation+5V and-5V voltage, give circuit supply, the 4th pin of the power module 5D5 of DC-DC translation circuit (23) connects public ground.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNA2009100224529A CN101551268A (en) | 2009-05-11 | 2009-05-11 | Piezoelectric type infrasonic sensor capable of offsetting mechanical vibration signals |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNA2009100224529A CN101551268A (en) | 2009-05-11 | 2009-05-11 | Piezoelectric type infrasonic sensor capable of offsetting mechanical vibration signals |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN101551268A true CN101551268A (en) | 2009-10-07 |
Family
ID=41155634
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNA2009100224529A Withdrawn CN101551268A (en) | 2009-05-11 | 2009-05-11 | Piezoelectric type infrasonic sensor capable of offsetting mechanical vibration signals |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN101551268A (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103644964A (en) * | 2013-12-10 | 2014-03-19 | 昆明理工大学 | Vibration-wire-type infrasonic wave sensor based on PVDF |
| CN103868582A (en) * | 2014-03-14 | 2014-06-18 | 昆明理工大学 | Optical fiber Bragg grating-based vibrating wire infrasonic wave sensor |
| CN105202373A (en) * | 2015-09-09 | 2015-12-30 | 北京科创三思科技发展有限公司 | Acoustic detection sensor for urban gas pipe network |
| CN105806470A (en) * | 2015-01-15 | 2016-07-27 | 赫拉胡克公司 | Method and device for detecting a structure-borne sound signal |
| CN107299832A (en) * | 2017-06-30 | 2017-10-27 | 西安石油大学 | A kind of method that use frequency difference formula infrasonic wave generator measures well fluid level |
-
2009
- 2009-05-11 CN CNA2009100224529A patent/CN101551268A/en not_active Withdrawn
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103644964A (en) * | 2013-12-10 | 2014-03-19 | 昆明理工大学 | Vibration-wire-type infrasonic wave sensor based on PVDF |
| CN103868582A (en) * | 2014-03-14 | 2014-06-18 | 昆明理工大学 | Optical fiber Bragg grating-based vibrating wire infrasonic wave sensor |
| CN105806470A (en) * | 2015-01-15 | 2016-07-27 | 赫拉胡克公司 | Method and device for detecting a structure-borne sound signal |
| CN105202373A (en) * | 2015-09-09 | 2015-12-30 | 北京科创三思科技发展有限公司 | Acoustic detection sensor for urban gas pipe network |
| CN107299832A (en) * | 2017-06-30 | 2017-10-27 | 西安石油大学 | A kind of method that use frequency difference formula infrasonic wave generator measures well fluid level |
| CN107299832B (en) * | 2017-06-30 | 2021-04-13 | 西安石油大学 | Method for measuring working fluid level of oil well by using frequency difference type infrasonic wave generator |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN101034156B (en) | Piezoelectric infrasonic wave sensor capable of canceling mechanical oscillation signal | |
| CN101551268A (en) | Piezoelectric type infrasonic sensor capable of offsetting mechanical vibration signals | |
| CN106449966B (en) | A kind of piezoelectric sensing device and application | |
| CN101403635A (en) | Infrasonic wave detection apparatus | |
| CN100454028C (en) | Impedance measuring circuit, its method, and capacitance measuring circuit | |
| CN204832539U (en) | Active seismic sensor of high sensitivity three -component | |
| US10240991B2 (en) | Vibration and dynamic acceleration sensing using capacitors | |
| CN102206996A (en) | Weak signal detector | |
| CN106054088B (en) | It is a kind of improve magnetic flux transducer dynamic output range from zero amplifying circuit | |
| CN204228369U (en) | A kind of calibrating installation of vibration table | |
| CN1246678C (en) | Digital vibration and impact sensor | |
| CN103630273A (en) | Device for measuring quasi-static force via piezoelectric sensing element | |
| CN203965527U (en) | A kind of electrostatic admeasuring apparatus | |
| CN1236307C (en) | Low-frequency sound wave stacked piezo-electric transducer | |
| CN113503958B (en) | Broadband vibration signal sensor and signal processing device thereof | |
| CN210005707U (en) | miniature high-sensitivity magnetoelectric speed machine | |
| CN103968995B (en) | Based on the fluid pressure sensor of elasticity pressure measurement | |
| CN103389512B (en) | For the digital collection transmission circuit of air gun source near-field wavelet and auxiliary signal | |
| CN202350904U (en) | Integrated vibration transmitter | |
| CN207281089U (en) | A kind of compact acceleration sensor module | |
| CN202260045U (en) | Vibration detection conversion line | |
| CN201974267U (en) | Pressure measuring instrument | |
| CN203811315U (en) | Fluid pressure sensor based on elastic pressure measurement | |
| CN203870098U (en) | Electrode plate of micro-sensor | |
| RU2813636C1 (en) | Set of devices for measuring the parameters of mechanical vibrations of objects with temperature error compensation |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C04 | Withdrawal of patent application after publication (patent law 2001) | ||
| WW01 | Invention patent application withdrawn after publication |