CN207908704U - A kind of differential type bimorph geophone core and piezoelectric seismometer - Google Patents
A kind of differential type bimorph geophone core and piezoelectric seismometer Download PDFInfo
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Abstract
The utility model discloses a kind of differential type bimorph geophone core and piezoelectric seismometers, core includes cantilever beam substrate made of elastic material and the first end piezoelectric patches group for being located at cantilever beam substrate left and right ends and the second terminal voltage piece group, two groups of piezoelectric patches groups all have upper end piezoelectric patches and lower end piezoelectric patches, the lower surface of cantilever beam substrate is fixed in the upper surface of each lower end piezoelectric patches, the lower surface of cantilever beam substrate is fixed in the lower surface of each upper end piezoelectric patches, the upper surface of each lower end piezoelectric patches and each upper end piezoelectric patches, upper surface electrode is respectively provided on lower surface, lower surface electrode, each upper surface electrode and each lower surface electrode draw output lead respectively.The geophone for providing core based on the utility model has many advantages, such as high sensitivity, strong antijamming capability, wide dynamic range, Portable durable, and in underground, the application of the fields such as seam seismic exploration, land seismic exploration is more reliable and extensive.
Description
Technical Field
The utility model relates to a seismic exploration field, more specifically say, relate to a differential type dual piezoelectric patches geophone core and piezoelectricity geophone.
Background
The geophone is a special sensor applied to the fields of geological exploration and engineering measurement, and is used for converting direct waves artificially exciting a seismic source or reflected waves of various strata into electric signals and then inputting the electric signals into a seismic instrument. The detector can be divided into magnetoelectric detectors, eddy current detectors, piezoelectric detectors and the like according to the working principle. The seismic detectors can be divided into land exploration seismic detectors, underwater seismic detectors applied to exploration in rivers, lakes and seas and borehole seismic detectors applied to seismic logging according to application environments. The detector is divided into a velocity type detector and an acceleration type detector according to an energy conversion mechanism. The method can be divided into longitudinal wave detectors also called vertical detectors, transverse wave detectors also called horizontal detectors and three-component detectors. Geophones can also be divided into active geophones and passive geophones. The traditional mechanical moving-coil type and eddy current detectors belong to passive detectors, while the piezoelectric detector belongs to active detectors.
At present, the most widely used domestic is the traditional analog geophone, the output of the seismic wave sensing device is an analog signal, and the conventional or super-speed geophone is mainly used on land. The detectors are basically magnetoelectric detectors and eddy current detectors, the internal structures of the detectors are all composed of permanent magnets and coils, and the purpose of seismic exploration is achieved by the interaction of the coils and the permanent magnets by basically applying the electromagnetic induction principle. The detectors are internally provided with high-elasticity structures such as coils, large relative motion is easy to occur among all parts to generate deformation, so that waveforms are easy to generate deformation, further signal distortion is caused, the performance of a permanent magnet is changed, the magnetism is faded along with time, the service life of the permanent magnet is short, the permanent magnet is easy to be influenced by the environment, the stability is low, and the seismic exploration requirements of high precision and high resolution cannot be met. As a first step seismic signal acquisition process, the detector device cannot obtain better original seismic signals, directly influences the quality of acquired seismic data, limits the capability of obtaining a complex geological structure by adopting a seismic exploration method, and becomes one of the main bottlenecks restricting the development of a petroleum geophysical prospecting technology. With the improvement of high-precision oil-gas exploration technology and the increase of oil-gas exploration complexity, the geophone is developing towards the directions of low distortion, high sensitivity and wide frequency band, has a large dynamic range, wide frequency response, small equivalent input noise, a small volume, light weight and strong anti-electromagnetic interference capability, meets the requirement of high-resolution acquisition, and is the development trend of the current geophone. Various new types of detectors using different new technologies and materials are beginning to emerge.
The piezoelectric acceleration geophone is a novel geophone which appears in recent years, has a simple internal structure and no magnetic steel or coil, so that the geophone has the advantages of high rigidity, small deformation, small waveform distortion, stable performance and high resolution, and is a high-fidelity geophone with higher sensitivity. Yuan Baoding et al developed an inertial piezoelectric amphibious detector in 1993 (Chinese patent 93232320.0); the Duke et al developed a land-used piezoelectric ceramic geophone (Chinese patent 00226749.7); YD20OO land piezoelectric seismic acceleration detector (Chinese patent 200420042025.X) was developed by Lumega qi, and traditional lead-acid zirconium and zirconium titanate [ PbZrO ] were adopted3-PbTiO3]The piezoelectric detector (PZT for short) has high natural frequency and good high-frequency response, but is influenced by the defects of low piezoelectric constant, high impedance and the like of the traditional piezoelectric element, so the dynamic range is small, the impedance is high, and the low-frequency response is low. Research shows that the novel relaxation ferroelectric crystal lead magnesium niobate-lead titanate [ xPb (Mg)1/3Nb2/3)O3-(1-x)PbTiO3]The main piezoelectric performance indexes of (PMNT for short) are far higher than that of the PZT piezoelectric ceramics which are generally used at present. The relaxor ferroelectric single crystal material has a high piezoelectric constant g33、d33Coefficient of electromechanical coupling k33Dielectric constant ε33 TAnd lower electrical loss, and the comprehensive performance of the composite material is more superior to that of PZT ceramic. The relaxation type ferroelectric single crystal material is used as a sensing element of the piezoelectric geophone, and a geophone core body structure matched with the relaxation type ferroelectric single crystal material is designed, so that the performance advantage of the single crystal material is fully exerted, and the sensitivity of the single crystal material is expected to be greatly improved.
SUMMERY OF THE UTILITY MODEL
The to-be-solved technical problem of the utility model is, for the sensitivity that overcomes current piezoelectricity geophone existence not enough, the poor not enough of low frequency response, provide a differential type bimorph geophone core and piezoelectricity geophone, adopt cantilever beam formula structure geophone core to increase the sensitivity of geophone in the finite space, improve its low frequency response performance.
According to one aspect of the present invention, the present invention provides a differential type dual-piezoelectric-sheet geophone core comprising a cantilever beam substrate made of an elastic material and a first end piezoelectric sheet set and a second end piezoelectric sheet set respectively located at the left and right ends of the cantilever beam substrate, wherein the left end or the right end of the cantilever beam substrate is used for rigidly connecting the inner wall of a casing of the piezoelectric geophone, each of the two piezoelectric sheet sets comprises an upper end piezoelectric sheet and a lower end piezoelectric sheet, the upper surface of each lower end piezoelectric sheet is fixed to the lower surface of the cantilever beam substrate, the lower surface of each upper end piezoelectric sheet is fixed to the lower surface of the cantilever beam substrate, the voltage series connection or the current parallel connection between all the upper end piezoelectric sheets is used for outputting as a first group after signal superposition, the voltage series connection or the current parallel connection between all the lower end piezoelectric sheets is used, the two sets of outputs form a differential output signal.
Preferably, in the differential dual-piezoelectric-sheet geophone core of the present invention, the cantilever beam base is made of beryllium bronze or phosphor bronze.
Preferably, in the differential dual-piezoelectric-sheet geophone core of the present invention, each lower piezoelectric sheet and each upper piezoelectric sheet are of a single-layer structure and made of piezoelectric single crystal PMN-PT; or,
all or part of each lower end piezoelectric sheet and each upper end piezoelectric sheet are of a structure of a plurality of piezoelectric single crystals, each piezoelectric single crystal contained in each lower end piezoelectric sheet and each upper end piezoelectric sheet is arranged and connected according to the crystal polarization direction, and each piezoelectric single crystal is made of piezoelectric single crystals PMN-PT.
Preferably, in the differential dual-piezoelectric-sheet geophone core of the present invention, the crystal directions of the upper piezoelectric sheet and the lower piezoelectric sheet of the first end piezoelectric sheet set are <110> directions, the direction of the polarized electric field is parallel to the thickness direction thereof, and the transduction mode is d31 transduction mode; the crystal orientation of the upper end piezoelectric sheet and the lower end piezoelectric sheet of the second end piezoelectric sheet group is a <001> direction, the direction of the polarization electric field is parallel to the thickness direction of the upper end piezoelectric sheet and the lower end piezoelectric sheet, and the transduction mode is a d33 transduction mode.
Preferably, in the differential dual-piezoelectric-sheet geophone core according to the present invention, each of the lower piezoelectric sheets and each of the upper piezoelectric sheets has an upper surface electrode and a lower surface electrode on the upper surface and the lower surface thereof, respectively, and each of the upper surface electrodes and each of the lower surface electrodes has an output lead respectively, and the electrode material of each of the upper surface electrodes and each of the lower surface electrodes is silver or gold; the output leads led out from the upper surface electrodes and the lower surface electrodes are copper wires.
Preferably, in the differential type bimorph geophone core of the present invention, in each of the left and right ends of the cantilever beam base: the positions of the lower end piezoelectric sheet and the upper end piezoelectric sheet are vertically symmetrical relative to the cantilever beam substrate, and the performance of converting stress into an electric signal is consistent.
Preferably, in the utility model discloses an in the differential type bimorph geophone core, the one of them one end place region of cantilever beam basement is fixed with two quality pieces that the quality is the same, the other end be used for with the shell inner wall rigid connection of piezoelectric geophone, two quality pieces about the cantilever beam basement longitudinal symmetry setting.
Preferably, in the differential dual-piezoelectric-sheet geophone core according to the present invention, the two mass blocks are respectively located on the upper surface of the upper piezoelectric sheet and the lower surface of the lower piezoelectric sheet of one of the piezoelectric sheet sets, one of the surfaces of the mass blocks is the same as the surface of the upper piezoelectric sheet/lower piezoelectric sheet connected thereto, and the two are connected to each other in a manner of completely covering each other.
According to the utility model discloses a on the other hand, the utility model discloses a solve its technical problem, still provide a piezoelectricity geophone, including the two bimorph geophone cores of the differential type of above-mentioned arbitrary one, the cantilever beam basement's of the two bimorph geophone cores of differential type one end with piezoelectricity geophone's shell inner wall rigid connection.
Preferably, the utility model discloses an among the piezoelectric geophone, the cantilever beam basement's of piezoelectric geophone core one end pass through the base with the shell inner wall rigid connection of piezoelectric geophone, the cantilever beam basement's of piezoelectric geophone core one end rigid connection in on the base, the base with the shell inner wall rigid connection of piezoelectric geophone
Based on the utility model discloses a piezoelectricity geophone that differential type bimorph geophone core realized has advantages such as sensitivity height, dynamic range width, light durable, and the differential type structure that adopts compares in non-differential type structure, and the interference killing feature is stronger, uses more reliably and extensively in fields such as land seismic exploration, groove wave seismic exploration in the pit.
Drawings
The invention will be further explained with reference to the drawings and examples, wherein:
fig. 1 is a schematic structural view of a preferred embodiment of a differential dual-piezoelectric-sheet geophone core according to the present invention;
FIG. 2 is a graph of the sensitivity-frequency relationship of the novel PMN-PT piezoelectric material to the PZT material under the cantilever beam structure of FIG. 1;
fig. 3 is a schematic structural diagram of another embodiment of the core body of the piezoelectric geophone according to the present invention.
Detailed Description
In order to clearly understand the technical features, objects, and effects of the present invention, embodiments of the present invention will be described in detail with reference to the accompanying drawings.
Fig. 1 is a schematic structural diagram of a preferred embodiment of the differential dual-piezoelectric-sheet geophone core according to the present invention. This differential type bimorph geophone core includes: the cantilever beam comprises a cantilever beam substrate 2, an upper end piezoelectric sheet 3, a lower end piezoelectric sheet 4, an upper end piezoelectric sheet 5, a lower end piezoelectric sheet 6, a mass block 7 and a mass block 8, wherein a first end piezoelectric sheet group formed by the upper end piezoelectric sheet 3 and the lower end piezoelectric sheet 4 is positioned at the right end-B end of the cantilever beam substrate, a second end piezoelectric sheet group formed by the upper end piezoelectric sheet 5 and the lower end piezoelectric sheet 6 is positioned at the left end-A end of the cantilever beam substrate, the mass block 7 is fixed on the upper surface of the upper end piezoelectric sheet 3, and the mass block 8 is fixed on the lower surface of. The cantilever beam substrate 2 is made of an elastic element which is more sensitive to vibration and can increase the sensitivity of the core body of the piezoelectric geophone, and the elastic element can be preferably made of beryllium bronze or phosphor bronze. The lower surface of the upper end piezoelectric sheet 5 is adhered to the upper surface of the end A of the cantilever beam substrate 2, the upper surface of the lower end piezoelectric sheet 6 is adhered to the lower surface of the end A of the cantilever beam substrate 2, the differential type dual-piezoelectric-sheet geophone is provided with a base 1, the end A of the cantilever beam substrate 2 is rigidly connected to the base 1, the cantilever beam substrate 2 is horizontally arranged, and the base 1 and the geophone are arranged in a horizontal modeThe shell of the detector is rigidly connected; the lower surface of the upper end piezoelectric sheet 3 is adhered to the upper surface of the end B of the cantilever beam substrate 2, and the upper surface of the lower end piezoelectric sheet 4 is adhered to the lower surface of the end B of the cantilever beam substrate 2. The upper surface of the upper end piezoelectric sheet 3 and the lower surface of the lower end piezoelectric sheet 4 are respectively fixed with a mass block 7 and a mass block 8 which are made of alloy such as steel or tungsten, and the two mass blocks are preferably arranged in an up-and-down symmetrical mode relative to the cantilever beam substrate, and are symmetrical in position and identical in mass. The mass 7 and the mass 8 can generate larger strain on the upper piezoelectric sheet 3 and the lower piezoelectric sheet 4. For different piezoelectric seismometers, the sensitivity and the resonant frequency of the geophone are designed by setting the mass blocks to have different masses; the bottom surface of the mass block 7 and the upper surface of the upper end piezoelectric plate 3 are same in size and shape and are not connected in a staggered mode, the upper surface of the mass block 8 and the lower surface of the lower end piezoelectric plate 4 are same in size and shape and are not connected in a staggered mode, and the two mass blocks are same in mass; the upper end piezoelectric sheet 3, the lower end piezoelectric sheet 4, the upper end piezoelectric sheet 5 and the lower end piezoelectric sheet 6 convert the force into an electric signal, the upper surface electrode and the lower surface electrode are respectively arranged on the upper surface and the lower surface of the upper end piezoelectric sheet 3, the lower end piezoelectric sheet 4, the upper end piezoelectric sheet 5 and the lower end piezoelectric sheet 6, output wires are respectively led out of the surface electrodes, and the output wires can be made of copper. The upper end piezoelectric sheet 3 and the upper end piezoelectric sheet 5 are connected in a voltage series connection (voltage superposition) or current parallel connection (current addition) mode to form a group of outputs, the lower end piezoelectric sheet 4 and the lower end piezoelectric sheet 6 are connected in a voltage series connection or current parallel connection mode to form a group of outputs, the two groups of outputs form a pair of differential signals after the core body of the piezoelectric geophone with the symmetrical structure senses vibration, and the differential model has stronger anti-interference capability. In FIG. 1, F (t) represents that the force received by the end a of the detector during earth vibration is transmitted to the end b, and the force received by the end b is FB(t) wherein FBK is a constant transfer coefficient.
The electrode material of the upper surface electrode and the lower surface electrode may be silver, copper, or gold. The upper end piezoelectric strip 3 is of a single-layer structure, has the size of 10mm x 1mm, is made of piezoelectric single crystals (PMN-PT), and is arranged in each of the left end and the right end of the cantilever beam substrate: the positions of the upper end piezoelectric sheet 3 and the lower end piezoelectric sheet 4, and the positions of the lower end piezoelectric sheet 6 and the upper end piezoelectric sheet 5 are respectively up-down symmetrical about the cantilever beam substrate, and the performances of converting stress into electric signals are consistent, so that the differential signals are easier to process in the later stage. The crystal directions of the upper end piezoelectric sheet 5 and the lower end piezoelectric sheet 6 of the A-end piezoelectric sheet group are in a <110> direction, the direction of a polarization electric field is parallel to the thickness direction of the piezoelectric sheet, and the transduction mode is a d31 transduction mode; the crystal orientation of the upper end piezoelectric plate 3 and the lower end piezoelectric plate 6 of the B-end piezoelectric plate group is the <001> direction, the polarization electric field direction is parallel to the thickness direction, and the transduction mode is the d33 transduction mode, but the utility model is not limited to this mode.
FIG. 2 shows that, in the cantilever structure, the model sensitivity of the model with the piezoelectric material PMN-PT in the frequency range of 0-1000Hz is higher than that of the model with the piezoelectric material PZT-5A. The sensitivity of a double piezoelectric sheet combined cantilever beam model with the piezoelectric material PMN-PT in the range of 0-1000Hz is 13.5-63.6mV/ms-2The sensitivity of the model is not only higher than that of a PZT-5A double piezoelectric sheet combined cantilever beam model, but also higher than that of a central compression structure model and a single piezoelectric sheet cantilever beam model which are made of PMN-PT piezoelectric materials. This is because the bimorph combined cantilever structure simultaneously utilizes the d of the piezoelectric material31And d33Two transduction modes. This shows that the sensitivity of the geophone can be greatly improved by taking the PMN-PT as the sensitive material of the geophone.
Reference is made to fig. 3, which is a schematic structural diagram of another embodiment of the core body of the piezoelectric geophone according to the present invention. In the present embodiment, the difference from the embodiment shown in fig. 1 is that: all or part of each lower end piezoelectric sheet and each upper end piezoelectric sheet are in a structure of a plurality of piezoelectric single crystals, the piezoelectric single crystals contained in each lower end piezoelectric sheet and each upper end piezoelectric sheet are arranged and connected according to the crystal polarization direction, the positions of the lower end piezoelectric sheet and the upper end piezoelectric sheet at each end are still vertically symmetrical relative to the cantilever beam substrate, and the performance of converting stress into electric signals is consistent. In this embodiment, each piezoelectric single crystal is realized by 3, 4, 5, 6, 7, 8, 9, and 10 using piezoelectric sheets, the upper piezoelectric sheet at the a end has two piezoelectric sheets 7 and 8, the lower piezoelectric sheet at the a end has two piezoelectric sheets 9 and 10, the upper piezoelectric sheet at the B end has two piezoelectric sheets 3 and 4, the lower piezoelectric sheet at the B end has two piezoelectric sheets 5 and 6, and the piezoelectric sheets are arranged in the same crystal polarization direction for bonding, so that the current and voltage transmission between two connected piezoelectric sheets can be realized after bonding. The crystal orientation of the piezoelectric sheets 7, 8, 9 and 10 is the <110> direction, the direction of the polarization electric field is parallel to the thickness direction, and the transduction mode is the d31 transduction mode; the crystal orientation of the piezoelectric sheets 3, 4, 5, 6 is the <001> direction, the polarization electric field direction is parallel to the thickness direction, and the transduction mode is the d33 transduction mode. The upper and lower surfaces of the piezoelectric sheets are plated with electrodes, and lead wires are led out, and the electrodes of the two connected piezoelectric sheets are electrically connected. The wires are led out from the upper surfaces of the piezoelectric sheets 4, 5, 7 and 9, and the wires are led out from the lower surfaces of the piezoelectric sheets 3, 6, 8 and 10. The outputs of the piezoelectric sheets 3 and 4 and the outputs of the piezoelectric sheets 7 and 8 are connected in a voltage series or current parallel mode to form a group of outputs, the outputs of the piezoelectric sheets 9 and 10 and the outputs of the piezoelectric sheets 5 and 6 are connected in a voltage series or current parallel mode to form a group of outputs, and the upper and lower voltage sheets symmetrical to the cantilever beam substrate 2 are connected in the same mode. The two groups of outputs form a pair of differential signals, and the core body of the piezoelectric geophone with the symmetrical structure has stronger anti-interference capability after sensing vibration. In this embodiment, since the upper end piezoelectric sheet and the lower end piezoelectric sheet formed by a plurality of piezoelectric single crystals are formed, compared with the upper end piezoelectric sheet and the lower end piezoelectric sheet formed by only one piezoelectric single crystal in fig. 1, a signal formed by piezoelectric induction can be larger and stronger. In another embodiment of the present invention, the output lead between two connected piezoelectric patches can also be directly eliminated and electrically connected, and the specific connection method belongs to the common knowledge and is not described herein again.
The working principle of the utility model is that; when the core body of the piezoelectric cantilever beam is subjected to large earthquake, the piezoelectric cantilever beam can vibrate with the same frequency and amplitude along with the earth vibration, the B end of the piezoelectric cantilever beam can be stressed to deform under the action of the mass block, and due to the positive piezoelectric effect of the piezoelectric material, when the piezoelectric material deforms, mechanical energy can be converted into electric energy, and then electric signals on two piezoelectric patches are collected, so that earthquake electric signals can be obtained. It should be understood that the embodiments shown in fig. 1 and 3 may be without the mass, and the core may also function properly; the upper end voltage sheet and the lower end voltage sheet are not necessarily arranged at the left end point and the right end point of the end where the cantilever beam base is arranged, and the distance between the upper end voltage sheet and the lower end voltage sheet and the end point of the end where the cantilever beam base is arranged does not exceed one third of the length of the cantilever beam base.
The utility model discloses core simple structure, the quality is light, and is small, utilizes the structure of list piezoelectric patches cantilever beam, applicable in the low frequency vibration environment, has sensitivity along with the characteristic that the frequency risees simultaneously, because the seismic wave signal is lossy at the in-process of propagating, the higher seismic wave of frequency gets bigger at the in-process amplitude attenuation of propagating, can compensate the attenuation that seismic wave amplitude produced along with the frequency increase to a certain extent.
The utility model provides a wave detector core structure utilizes the vibration drive cantilever beam structure vibration of environment of locating to make the piezoelectric patches produce bending deformation, make and produce effective electric potential between the different electrodes of piezoelectric patches, thereby can make the more effectual output energy of piezoelectricity.
The utility model provides a wave detector core structure, full play piezoelectric single crystal (PMN-PT)'s anisotropic performance, make full use of piezoelectric material's d31And d33Two transduction modes. The electrodes of the piezoelectric sheet are arranged as upper and lower surface electrodes, and the polarization direction is the same as the direction of compression (thickness direction). The performance of the piezoelectric sheet is more effectively exerted by utilizing the Poisson effect of the piezoelectric sheet when the piezoelectric sheet is bent, and the energy output efficiency of the piezoelectric sheet is improved.
Generally speaking, based on the utility model provides a geophone of core structure has advantages such as sensitivity height, interference killing feature are strong, dynamic range is wide, light durable, uses more reliably and extensively in fields such as pit wave seismic exploration, land seismic exploration.
While the embodiments of the present invention have been described with reference to the accompanying drawings, the present invention is not limited to the above-described embodiments, which are merely illustrative and not restrictive, and many modifications may be made by one skilled in the art without departing from the spirit and scope of the present invention as defined in the appended claims.
Claims (9)
1. A core body of a differential type double-piezoelectric-piece geophone is characterized by comprising a cantilever beam substrate made of elastic materials, and a first end piezoelectric piece group and a second end piezoelectric piece group which are respectively positioned at the left end and the right end of the cantilever beam substrate, wherein the left end or the right end of the cantilever beam substrate is used for being rigidly connected with the inner wall of a shell of the piezoelectric geophone, the two groups of piezoelectric piece groups are respectively provided with an upper end piezoelectric piece and a lower end piezoelectric piece, the upper surface of each lower end piezoelectric piece is fixed on the lower surface of the cantilever beam substrate, the lower surface of each upper end piezoelectric piece is fixed on the lower surface of the cantilever beam substrate, signals are output as a first group after being superposed by voltage series connection or current parallel connection among all the upper end piezoelectric pieces, the signals are output as a second group after being superposed by;
each lower end piezoelectric piece and each upper end piezoelectric piece are of a single-layer structure and are made of piezoelectric single crystals PMN-PT; or,
all or part of each lower end piezoelectric sheet and each upper end piezoelectric sheet are of a structure of a plurality of piezoelectric single crystals, each piezoelectric single crystal contained in each lower end piezoelectric sheet and each upper end piezoelectric sheet is arranged and connected according to the crystal polarization direction, and each piezoelectric single crystal is made of piezoelectric single crystals PMN-PT.
2. The differential bimorph geophone core according to claim 1, wherein said cantilever beam base is of beryllium bronze or phosphor bronze.
3. The differential bimorph geophone core according to claim 1, wherein the crystal orientation of the upper and lower piezoelectric plates of the first end piezoelectric plate group is <110> direction, the direction of the polarization electric field is parallel to the thickness direction thereof, and the transduction mode is d31 transduction mode; the crystal orientation of the upper end piezoelectric sheet and the lower end piezoelectric sheet of the second end piezoelectric sheet group is a <001> direction, the direction of the polarization electric field is parallel to the thickness direction of the upper end piezoelectric sheet and the lower end piezoelectric sheet, and the transduction mode is a d33 transduction mode.
4. The differential bimorph geophone core according to claim 1, wherein each of the lower end piezoelectric plates and each of the upper end piezoelectric plates has an upper surface electrode and a lower surface electrode on the upper surface and the lower surface of each of the piezoelectric plates, respectively, and output leads are led out from each of the upper surface electrodes and the lower surface electrodes, respectively, and the electrode material of each of the upper surface electrodes and the lower surface electrodes is silver or gold; the output leads led out from the upper surface electrodes and the lower surface electrodes are copper wires.
5. The differential bimorph geophone core according to claim 1, wherein in each of the left and right ends of the cantilever base: the positions of the lower end piezoelectric sheet and the upper end piezoelectric sheet are vertically symmetrical relative to the cantilever beam substrate, and the performance of converting stress into an electric signal is consistent.
6. The differential bimorph geophone core according to claim 1, wherein two masses of the same mass are fixed to the cantilever base in the area of one of its ends and the other end is adapted to be rigidly connected to the inner wall of the housing of the piezoelectric geophone, the two masses being arranged vertically symmetrically with respect to the cantilever base.
7. The differential bimorph geophone core according to claim 6, wherein said two masses are located on the upper surface of the upper end piezoelectric plate and the lower surface of the lower end piezoelectric plate of one of the piezoelectric plate groups, respectively, and one of the surfaces of the masses is in the same size as the surface of the upper end piezoelectric plate/lower end piezoelectric plate to which it is connected and is connected so as to completely cover each other.
8. A piezoelectric geophone comprising a differential bimorph geophone core according to any one of claims 1-7, wherein one end of the cantilever base of said differential bimorph geophone core is rigidly connected to the inner wall of the casing of said piezoelectric geophone.
9. The piezoelectric geophone of claim 8, wherein one end of the cantilever base of the piezoelectric geophone core is rigidly connected to the inner wall of the casing of the piezoelectric geophone by a base, one end of the cantilever base of the piezoelectric geophone core is rigidly connected to the base, and the base is rigidly connected to the inner wall of the casing of the piezoelectric geophone.
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN107870350A (en) * | 2017-12-13 | 2018-04-03 | 中国地质大学（武汉） | A kind of differential type bimorph geophone core body and piezoelectric seismometer |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107870350A (en) * | 2017-12-13 | 2018-04-03 | 中国地质大学（武汉） | A kind of differential type bimorph geophone core body and piezoelectric seismometer |
| CN107870350B (en) * | 2017-12-13 | 2023-12-15 | 中国地质大学（武汉） | Differential dual-piezoelectric-patch geophone core and piezoelectric geophone |
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