CN110954209A - Differential acoustic emission and acceleration integrated piezoelectric sensor - Google Patents
Differential acoustic emission and acceleration integrated piezoelectric sensor Download PDFInfo
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- CN110954209A CN110954209A CN201911390434.6A CN201911390434A CN110954209A CN 110954209 A CN110954209 A CN 110954209A CN 201911390434 A CN201911390434 A CN 201911390434A CN 110954209 A CN110954209 A CN 110954209A
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- 230000001133 acceleration Effects 0.000 title claims abstract description 29
- 239000010453 quartz Substances 0.000 claims description 3
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N silicon dioxide Inorganic materials O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims description 3
- 238000005259 measurement Methods 0.000 abstract description 10
- 230000001360 synchronised effect Effects 0.000 abstract description 3
- 239000012212 insulator Substances 0.000 abstract 2
- 230000010354 integration Effects 0.000 abstract 1
- 239000000463 material Substances 0.000 description 5
- 238000012545 processing Methods 0.000 description 4
- 230000008859 change Effects 0.000 description 2
- 238000011160 research Methods 0.000 description 2
- 239000000853 adhesive Substances 0.000 description 1
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- 238000004458 analytical method Methods 0.000 description 1
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- HFGPZNIAWCZYJU-UHFFFAOYSA-N lead zirconate titanate Chemical compound [O-2].[O-2].[O-2].[O-2].[O-2].[Ti+4].[Zr+4].[Pb+2] HFGPZNIAWCZYJU-UHFFFAOYSA-N 0.000 description 1
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- 238000003199 nucleic acid amplification method Methods 0.000 description 1
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01H—MEASUREMENT OF MECHANICAL VIBRATIONS OR ULTRASONIC, SONIC OR INFRASONIC WAVES
- G01H11/00—Measuring mechanical vibrations or ultrasonic, sonic or infrasonic waves by detecting changes in electric or magnetic properties
- G01H11/06—Measuring mechanical vibrations or ultrasonic, sonic or infrasonic waves by detecting changes in electric or magnetic properties by electric means
- G01H11/08—Measuring mechanical vibrations or ultrasonic, sonic or infrasonic waves by detecting changes in electric or magnetic properties by electric means using piezoelectric devices
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01P—MEASURING LINEAR OR ANGULAR SPEED, ACCELERATION, DECELERATION, OR SHOCK; INDICATING PRESENCE, ABSENCE, OR DIRECTION, OF MOVEMENT
- G01P15/00—Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration
- G01P15/02—Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration by making use of inertia forces using solid seismic masses
- G01P15/08—Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration by making use of inertia forces using solid seismic masses with conversion into electric or magnetic values
- G01P15/09—Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration by making use of inertia forces using solid seismic masses with conversion into electric or magnetic values by piezoelectric pick-up
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Abstract
A differential acoustic emission and acceleration integrated piezoelectric sensor belongs to the technical field of aerospace. Differential acoustic emission and acceleration integration piezoelectric sensor, including connection base, connection base is provided with electrically conductive base, electrically conductive base is provided with insulator foot, piezoelectric element one and piezoelectric element two, insulator foot is provided with piezoelectric piece and piezoelectric piece down, it passes through the conducting strip with piezoelectric piece down to go up the piezoelectric piece and connects, it is provided with vibration conduction device to go up the piezoelectric piece, vibration conduction device passes through the spring and is connected with the casing, the upper surface of piezoelectric element one, the upper surface of going up the piezoelectric piece and the lower surface of piezoelectric piece down pass through the wire and be connected with the adapter, the upper surface and the conducting strip of piezoelectric element two pass through the wire and are connected with the adapter. The differential acoustic emission and acceleration integrated piezoelectric sensor realizes synchronous acquisition of vibration signals and acoustic emission signals, and can greatly reduce errors caused by independent measurement.
Description
Technical Field
The invention relates to the technical field of aerospace, in particular to a differential acoustic emission and acceleration integrated piezoelectric sensor.
Background
Problems caused by mechanical vibration are always important problems in the field of aviation, and researches on changes of physical parameters such as acceleration and internal mechanical properties of materials caused by vibration are breakthrough for researching vibration problems, so that researchers can acquire and analyze physical parameter data through various sensors. However, the current measuring instruments such as sensors only measure a single index, and when two or even more indexes need to be measured, the measurement needs to be performed by a plurality of sensors, which may result in an increase in measurement data error and a decrease in data accuracy.
Disclosure of Invention
In order to solve the technical problems in the prior art, the invention provides a differential acoustic emission and acceleration integrated piezoelectric sensor which can realize two-time acquisition of vibration signals generated by the same vibration, greatly reduce errors caused by separate measurement, ensure the accuracy of measurement and reduce the difficulty in measurement.
In order to achieve the purpose, the technical scheme of the invention is as follows:
a differential acoustic emission and acceleration integrated piezoelectric sensor comprises a connecting base, a conductive base, an insulating base, a shell, an upper piezoelectric sheet, a lower piezoelectric sheet, a first piezoelectric element, a second piezoelectric element and a vibration conduction device, wherein the connecting base is provided with a plurality of first piezoelectric elements;
the top of the connecting base is provided with a conductive base, the top of the conductive base is provided with an insulating base, a first piezoelectric element and a second piezoelectric element, the insulating base and the conductive base are coaxially arranged, and the first piezoelectric element and the second piezoelectric element are arranged on two sides of the insulating base;
an upper piezoelectric sheet and a lower piezoelectric sheet are arranged in the insulating base, the upper piezoelectric sheet and the lower piezoelectric sheet are connected through a conducting sheet, a vibration conduction device is arranged at the top of the upper piezoelectric sheet, the vibration conduction device is connected with a shell through a spring, and the shell is clamped with the connecting base;
the upper surface of piezoelectric element one, the upper surface of last piezoelectric patch and the lower surface of lower piezoelectric patch pass through the wire and are connected with the adapter, the upper surface and the conducting strip of piezoelectric element two pass through the wire and are connected with the adapter, and concrete connected mode is: the upper surface of the first piezoelectric element is connected with the adapter through a lead, and the upper surface of the upper piezoelectric sheet and the lower surface of the lower piezoelectric sheet are connected through leads and then led out of the shell through leads to be connected with the adapter; the upper surface of the second piezoelectric element is connected with the conducting strip through a wire, and then the conducting strip is led out of the shell through the wire and connected with the adapter.
An insulating block is arranged between the first piezoelectric element and the second piezoelectric element, and the first piezoelectric element and the second piezoelectric element are identical in structure and are symmetrically arranged.
The insulating base, the first piezoelectric element and the second piezoelectric element are located in the conductive base, and the depths of the insulating base, the first piezoelectric element and the second piezoelectric element are equal.
The vibration conduction device adopts a mass block and is used for conducting vibration identical to that of the connecting base.
The upper piezoelectric sheet and the lower piezoelectric sheet are both quartz piezoelectric sheets.
The bottom of the connecting base is provided with a connecting part used for being connected with a vibration part.
The invention has the beneficial effects that:
1) the invention can realize the two-time collection of the vibration signal generated by the same vibration, and form the collection of a plurality of physical quantities such as the acceleration of the vibration of the same object and the form change of the interior of the material, so as to accurately analyze the plurality of physical quantities;
2) through combining acoustic emission sensor and piezoelectric type acceleration sensor effectively, realize vibration signal and acoustic emission signal synchronous acquisition, can greatly reduce the error that the individual measurement is brought, reduce the degree of difficulty of a plurality of sensor installations simultaneously, both guaranteed the measuring accuracy, reduced the degree of difficulty when implementing the measurement again.
3) The vibration signal acquisition system can be applied to the vibration signal acquisition of various mechanical parts, and provides data acquisition preparation for multi-angle research and analysis of vibration characteristics, optimization of transmission characteristics of a structure and mechanical characteristics in subsequent work.
Additional features and advantages of the invention will be set forth in part in the detailed description which follows.
Drawings
FIG. 1 is a schematic front view of a differential acoustic emission and acceleration integrated piezoelectric sensor according to an embodiment of the present invention;
fig. 2 is a schematic top view of a differential acoustic emission and acceleration integrated piezoelectric sensor according to an embodiment of the present invention.
Reference numerals in the drawings of the specification include:
1-connection base, 2-conductive base, 3-insulating base, 4-shell, 5-upper piezoelectric plate, 6-lower piezoelectric plate, 7-first piezoelectric element, 8-second piezoelectric element, 9-vibration conduction device, 10-conductive plate, 11-connection part, 12-insulating block, 13-spring and 14-adapter.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments.
In the description of the present invention, it is to be understood that the terms "longitudinal", "lateral", "vertical", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate orientations or positional relationships based on those shown in the drawings, and are used only for convenience in describing the present invention and for simplicity in description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "a" and "an" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.
In the description of the present invention, unless otherwise specified and limited, it is to be noted that the terms "mounted," "connected," and "connected" are to be interpreted broadly, and may be, for example, a mechanical connection or an electrical connection, a communication between two elements, a direct connection, or an indirect connection via an intermediate medium, and specific meanings of the terms may be understood by those skilled in the art according to specific situations.
In order to solve the problems in the prior art, as shown in fig. 1 to 2, the present invention provides a differential acoustic emission and acceleration integrated piezoelectric sensor, which includes a connection base 1, a conductive base 2, an insulating base 3, a housing 4, an upper piezoelectric sheet 5, a lower piezoelectric sheet 6, a first piezoelectric element 7, a second piezoelectric element 8 and a vibration conduction device 9;
the top of the connecting base 1 is provided with a conductive base 2, the top of the conductive base 2 is provided with an insulating base 3, a first piezoelectric element 7 and a second piezoelectric element 8, the insulating base 3 and the conductive base 2 are coaxially arranged, and the first piezoelectric element 7 and the second piezoelectric element 8 are arranged on two sides of the insulating base 3;
an upper piezoelectric sheet 5 and a lower piezoelectric sheet 6 are arranged in the insulating base 3, the upper piezoelectric sheet 5 and the lower piezoelectric sheet 6 are both quartz piezoelectric sheets, the upper piezoelectric sheet 5 and the lower piezoelectric sheet 6 are in parallel connection structures, namely, polarities generated on the same side are opposite, the upper piezoelectric sheet 5 and the lower piezoelectric sheet 6 are connected through a conducting sheet 10, a vibration conduction device 9 is arranged at the top of the upper piezoelectric sheet 5, the vibration conduction device 9 adopts a mass block and is used for conducting vibration which is the same as that of the connecting base 1, the vibration conduction device 9 is connected with the shell 4 through a spring 13, and the shell 4 is clamped with the connecting base 1;
the upper surface of piezoelectric element 7, the upper surface of last piezoelectric patch 5 and the lower surface of lower piezoelectric patch 6 pass through the wire and are connected with adapter 14, and the upper surface of piezoelectric element two 8 and conducting strip 10 pass through the wire and are connected with adapter 14, and concrete connection mode is: the upper surface of the first piezoelectric element 7 is connected with the adapter 14 through a lead, the upper surface of the upper piezoelectric sheet 5 and the lower surface of the lower piezoelectric sheet 6 are connected through leads and then led out of the shell 4 through leads to be connected with the adapter 14, and the upper surface of the first piezoelectric element 7, the upper surface of the upper piezoelectric sheet 5 and the lower surface of the lower piezoelectric sheet 6 are both anodes or both cathodes; the upper surface of the second piezoelectric element 8 is connected with the conducting strip 10 through a lead, and then the conducting strip is led out of the shell 4 through the lead and is connected with the adapter 14, and the upper surface and the conducting strip are both anodes or both cathodes.
In this embodiment, the conductive base 2 is a conductive structure, and may also be formed by laying conductive adhesive, the conductive base 2 and the insulating base 3 are both circular structures, and the insulating base 3 is disposed at the center of the conductive base 2; an insulating block 12 is arranged between the first piezoelectric element 7 and the second piezoelectric element 8, the first piezoelectric element 7 and the second piezoelectric element 8 are identical in structure and are symmetrically arranged on two sides of the insulating base 3, the first piezoelectric element 7, the second piezoelectric element 8 and the insulating block 12 form a circular structure, and the insulating block 12 plays a role in supporting and fixing the first piezoelectric element 7 and the second piezoelectric element 8 and ensures synchronous extraction of signals. The insulating base 3, the first piezoelectric element 7 and the second piezoelectric element 8 are located at the same depth in the conductive base 2.
The first piezoelectric element 7 and the second piezoelectric element 8 are both made of PZT-5 materials, the first piezoelectric element 7 and the second piezoelectric element 8 form a differential structure, namely the two are opposite in polarity with the upper part and the lower part, and are connected with the conductive base 2 at the lower end, for example, the upper part of the first piezoelectric element 7 is a positive electrode and is led out of the shell 4 by a lead, the upper part of the second piezoelectric element 8 is a negative electrode and is led out by a lead and is connected with the conductive sheet 10 to be led out of the shell 4. The conductive base 2 is fixed to the connection base 1, and the bottom of the connection base 1 is provided with a connection portion 11 for connection of the vibration member, and the connection portion 11 such as a bolt hole is fixed to the vibration part. The connecting base 1 is clamped with the metal shell 4 above the connecting base, all sensor components are arranged inside the shell 4, and because the frequencies of the acoustic emission sensor and the piezoelectric acceleration sensor are different, the top of the shell 4 is connected with the spring 13 and is connected with the mass block for damping the vibration of the mass block. In the subsequent processing, the adapter 14 may be connected to an amplification circuit for signal processing.
The working principle of the differential acoustic emission and acceleration integrated piezoelectric sensor is as follows:
the first piezoelectric element 7 and the second piezoelectric element 8 form an acoustic emission sensor, and the acoustic emission sensor converts mechanical vibration generated by vibration components such as an engine and the like into an electric signal through the two piezoelectric elements which are arranged in a differential mode; in actual use, in order to ensure the symmetry of the structure and the symmetry of the anode and the cathode of an output signal, the requirements on the piezoelectric elements are strict, and two piezoelectric elements with the same specification and the same batch production and consistent material performance parameters are selected and placed in the conductive base 2, so that the measurement of the signal is more accurate; in the subsequent processing, the electric signal can be received by an acoustic emission detection system and then processed and analyzed, so as to deduce the change of the internal state of the material;
the upper piezoelectric plate 5, the lower piezoelectric plate 6 and the conducting plate 10 form a piezoelectric acceleration sensor, when the piezoelectric acceleration sensor senses vibration, the vibration conduction device 9 has the same vibration along with the connecting base 1, and the vibration conduction device 9 has an alternating force which is in direct proportion to the acceleration to act on the piezoelectric plate; due to the piezoelectric effect of the piezoelectric sheet, alternating charges are generated on the two surfaces, and when the vibration frequency is far lower than the natural frequency of the sensor, the output charges (voltage) of the sensor are in direct proportion to the acting force, namely the acceleration of the vibration component; acceleration can be obtained through an external circuit in subsequent processing, and the vibration speed or displacement of the test piece can be measured if a proper integrating circuit is added into an amplifier;
the combination of the acoustic emission sensor and the piezoelectric acceleration sensor is realized through the components such as the connecting base 1, the conductive base 2, the insulating base 3, the shell 4 and the vibration conduction device 9, the measurement of two index data is realized, the synchronization performance of data acquisition is improved, the experimental error is greatly reduced, the accuracy is improved, and the problem that the synchronization performance is poor in the information fusion online monitoring process of the existing single-function sensor is effectively solved.
While embodiments of the invention have been shown and described, it will be understood by those of ordinary skill in the art that: various changes, modifications, substitutions and alterations can be made to the embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.
Claims (7)
1. A differential acoustic emission and acceleration integrated piezoelectric sensor is characterized by comprising a connecting base, a conductive base, an insulating base, a shell, an upper piezoelectric sheet, a lower piezoelectric sheet, a first piezoelectric element, a second piezoelectric element and a vibration conduction device, wherein the connecting base is provided with a plurality of through holes;
the top of the connecting base is provided with a conductive base, the top of the conductive base is provided with an insulating base, a first piezoelectric element and a second piezoelectric element, the insulating base and the conductive base are coaxially arranged, and the first piezoelectric element and the second piezoelectric element are arranged on two sides of the insulating base;
an upper piezoelectric sheet and a lower piezoelectric sheet are arranged in the insulating base, the upper piezoelectric sheet and the lower piezoelectric sheet are connected through a conducting sheet, a vibration conduction device is arranged at the top of the upper piezoelectric sheet, the vibration conduction device is connected with a shell through a spring, and the shell is clamped with the connecting base;
the upper surface of piezoelectric element one, the upper surface of going up the piezoelectric patch and the lower surface of lower piezoelectric patch pass through the wire and are connected with the adapter, the upper surface and the conducting strip of piezoelectric element two pass through the wire and are connected with the adapter.
2. The integrated differential acoustic emission and acceleration piezoelectric sensor according to claim 1, wherein an insulating block is disposed between the first piezoelectric element and the second piezoelectric element, and the first piezoelectric element and the second piezoelectric element have the same structure and are symmetrically disposed.
3. The integrated differential acoustic emission and acceleration piezoelectric sensor of claim 1, wherein said insulating base, piezoelectric element one and piezoelectric element two are located at equal depth within said conductive base.
4. The integrated differential acoustic emission and acceleration piezoelectric sensor of claim 1, wherein said vibration conducting means employs a mass for conducting the same vibration as the connection base.
5. The integrated differential acoustic emission and acceleration piezoelectric sensor according to claim 1, wherein said upper piezoelectric plate and said lower piezoelectric plate are both quartz piezoelectric plates.
6. The integrated differential acoustic emission and acceleration piezoelectric sensor according to claim 1, wherein a connecting portion is provided at a bottom of the connecting base for connecting with a vibration member.
7. The integrated piezoelectric sensor for acoustic emission and acceleration difference of claim 1, wherein the upper surface of the first piezoelectric element is connected to the adapter through a wire, and the upper surface of the upper piezoelectric plate and the lower surface of the lower piezoelectric plate are connected to each other through a wire and then led out of the housing through a wire to be connected to the adapter; and the upper surface of the second piezoelectric element is connected with the conducting strip through a wire, and then the conducting strip is led out of the shell through the wire and is connected with the adapter.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201911390434.6A CN110954209A (en) | 2019-12-30 | 2019-12-30 | Differential acoustic emission and acceleration integrated piezoelectric sensor |
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| CN201911390434.6A CN110954209A (en) | 2019-12-30 | 2019-12-30 | Differential acoustic emission and acceleration integrated piezoelectric sensor |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113654583A (en) * | 2021-08-31 | 2021-11-16 | 西安交通大学 | Shear type vibration-ultrasonic composite sensor and measuring device |
| CN113702685A (en) * | 2021-08-31 | 2021-11-26 | 西安交通大学 | Piezoelectric type ultrasonic-transient earth voltage composite sensor and measuring device |
| CN113720390A (en) * | 2021-08-31 | 2021-11-30 | 西安交通大学 | Piezoelectric ultrasonic-vibration acceleration composite sensor and measuring device |
| CN117870974A (en) * | 2024-01-15 | 2024-04-12 | 中国特种设备检测研究院 | Low-frequency acoustic emission sensor for pipeline leakage detection and application method thereof |
-
2019
- 2019-12-30 CN CN201911390434.6A patent/CN110954209A/en active Pending
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113654583A (en) * | 2021-08-31 | 2021-11-16 | 西安交通大学 | Shear type vibration-ultrasonic composite sensor and measuring device |
| CN113702685A (en) * | 2021-08-31 | 2021-11-26 | 西安交通大学 | Piezoelectric type ultrasonic-transient earth voltage composite sensor and measuring device |
| CN113720390A (en) * | 2021-08-31 | 2021-11-30 | 西安交通大学 | Piezoelectric ultrasonic-vibration acceleration composite sensor and measuring device |
| CN113654583B (en) * | 2021-08-31 | 2022-05-06 | 西安交通大学 | Shear type vibration-ultrasonic composite sensor and measuring device |
| CN117870974A (en) * | 2024-01-15 | 2024-04-12 | 中国特种设备检测研究院 | Low-frequency acoustic emission sensor for pipeline leakage detection and application method thereof |
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