CN207851318U - A kind of piezoelectric seismometer - Google Patents

Abstract

A kind of piezoelectric seismometer, including simply supported beam substrate made of shell and elastic material, both ends on the length direction of simply supported beam substrate, which are rigidly attached to respectively on shell, to be horizontally disposed with, at least one piezoelectric patches group is provided in simply supported beam substrate, piezoelectricity conversion performance is all had in each piezoelectric patches group unanimously and about the upper end piezoelectric patches and lower end piezoelectric patches of the setting symmetrical above and below of simply supported beam substrate, intermediate ends piezoelectric patches group is wherein provided at the half length of simply supported beam substrate, the output formed after Signal averaging on all upper end piezoelectric patches and the output formed after the Signal averaging on all lower end piezoelectric patches form one group of differential wave, each upper end piezoelectric patches connects output lead to export the differential wave with each lower end piezoelectric patches.The piezoelectric seismometer of the utility model has many advantages, such as high sensitivity, wide dynamic range, Portable durable, strong antijamming capability, and the application of the fields such as seismic prospecting, underground seam seismic exploration is more reliable and extensive by land.

Description

A kind of piezoelectric seismometer

Technical field

The utility model is related to field of seismic exploration, more specifically to a kind of piezoelectric seismometer.

Background technology

Geophone is the direct wave of artificial explosive source or the reflected wave conversion on each stratum into electric signal, then defeated Enter a kind of sensor special being applied to geological prospecting and engineering measurement field to seismic instrument.It can be divided by operation principle The wave detectors such as magneto-electric, eddy current type and piezoelectric type.It can be divided into land seismic exploration wave detector by application environment, be applied to rivers The hydrophone of the marine exploration in lake, applied to the borehole seismometer in well-shooting.By energy conversion machine system point For two kinds of velocity profile wave detector and acceleration type wave detector.Longitudinal wave wave detector can be divided into from exploitation method and be also referred to as vertical detection Device and transversal wave detector are also referred to as horizontal pickup and three-component geophone.In addition, geophone can also be divided into active detection Device and passive seismometer.Traditional mechanical moving-coil type and eddy acceleration geophone belong to passive class wave detector, and piezoelectric seismometer category In active class wave detector.

Currently, the simulation geophone that domestic application is widest or traditional, this seismic wave sensing device output Be analog signal, land mainly uses conventional or super velocity profile wave detector.This kind of wave detector is essentially all magnetoelectricity Formula wave detector, eddy current type geophone, their internal structure are made of permanent magnet and coil, are essentially all using electricity Magnetic induction principle, by the interaction of coil and permanent magnet to achieve the purpose that seismic prospecting.Inside these wave detectors There is high flexibility structure as coil, larger relative motion is easy to happen between each component and generates deformation, so waveform is easy Generate deformation, in turn result in distorted signals, and due to the performance of permanent magnet can change and magnetism can with the time and Subside, the service life is not long and is vulnerable to the influence of environment, and stability is low, in high precision and high-resolution to meet Seismic prospecting requirement.Process is acquired as first step seismic signal, this detector device cannot obtain preferable original earthquake Signal has directly influenced the quality of acquisition seismic data, has limited and obtain complicated geological structure using method of seismic prospecting Ability becomes one of the main bottleneck for restricting the development of petroleum exploration technology.Raising with high-precision oil-gas exploration technology and oil The increase of gas exploration complexity, geophone towards low distortion, high sensitivity, develop by wide band direction, dynamic Range is big, frequency response is wide, equivalent input noise is small, small, light-weight and anti-electromagnetic interference capability is strong, meets high-resolution Acquisition requires, and is the trend of current seismic wave detector development.Various novel wave detectors using different new technologies, new material start Occur.

Piezoelectric acceleration geophone is exactly the novel wave detector occurred in recent years, and internal structure is simple, nonmagnetic steel And coil, so rigidity is big, deformation is small, and generated wave distortion is small, and performance is stablized, high resolution, be a sensitivity compared with High high fidelity geophone.Yuan's guarantor's ancient cooking vessel et al. had developed inertial piezoelectric Amphibious wave detector in 1993, and (China is specially Profit is 93232320.0)；Du Ke is equal to have developed land piezoelectric ceramic seismic detector (Chinese patent 00226749.7)；Liu Zhaoqi YD20OO types land piezoelectricity seismic acceleration wave detector (Chinese patent 200420042025.X) is had developed, traditional lead is all used Sour zirconium and zirconia titanate [PbZrO₃-PbTiO₃] (abbreviation PZT), the intrinsic frequency of piezoelectric seismometer is higher, and high frequency response is preferable, but It is the influence for the shortcomings of impedance is high since the piezoelectric constant by its traditional piezoelectric elements is low, so its dynamic range is small, impedance Height, low frequency response are low.Research shows that novel relaxor ferroelectric crystal lead magnesium niobate-lead titanate [xPb (Mg_1/3Nb_2/3)O₃-(1-x) PbTiO₃] (abbreviation PMNT) main piezoelectric property index all significantly larger than PZT piezoelectric ceramics for being commonly used.Relaxation iron Electric monocrystal material has higher piezoelectric constant g₃₃、d₃₃, electromechanical coupling factor k₃₃, permittivity ε₃₃ ^TWith lower electrical loss, Its comprehensive performance ratio PZT ceramics is more superior.Using relaxation Ferroelectric monocrystal material as the sensing element of piezoelectric type geophone Part designs matching detector core body structure, to give full play to the performance advantage of monocrystal material, will be expected to substantially improve it Sensitivity.

Utility model content

The technical problems to be solved in the utility model is, to overcome sensitivity existing for existing piezoelectric seismometer not Enough, low frequency response difference deficiency, provides a kind of piezoelectric seismometer, using freely-supported girder structure detector core body, to have The sensitivity for increasing wave detector in space is limited, its low frequency response performance is improved.

Wherein one side according to the present utility model, the utility model are to solve its technical problem, the piezoelectricity earthquake provided Wave detector, including simply supported beam substrate made of shell and elastic material, the both ends difference on the length direction of simply supported beam substrate is rigid Property, which is connected on shell, to be horizontally disposed with, and is provided at least one piezoelectric patches group in simply supported beam substrate, in each piezoelectric patches group It is consistent and about the upper end piezoelectric patches and lower end piezoelectric patches of the setting symmetrical above and below of simply supported beam substrate to all have piezoelectricity conversion performance, In intermediate ends piezoelectric patches group is provided at the half length of simply supported beam substrate, the signal on all upper end piezoelectric patches is folded The output formed after adding and the output formed after the Signal averaging on all lower end piezoelectric patches form one group of differential wave, it is each on End piezoelectric patches connects output lead to export the differential wave with each lower end piezoelectric patches.

In the piezoelectric seismometer of the utility model, simply supported beam substrate is made of beryllium-bronze or phosphor bronze.

In the piezoelectric seismometer of the utility model, the crystal orientation of intermediate ends piezoelectric patches is<001>Direction, polarization electricity Field direction is parallel to its thickness direction, and residing transducing pattern is d33 transducing patterns.

In the piezoelectric seismometer of the utility model, also there is a mass block group, there are two matter for mass block group tool Identical and the setting symmetrical above and below of simply supported beam substrate mass block is measured, the two mass blocks are respectively arranged at intermediate ends piezoelectric patches group On that face of the separate simply supported beam substrate of upper end piezoelectric patches and lower end piezoelectric patches.

In the piezoelectric seismometer of the utility model, both ends or wherein one end in simply supported beam base length direction Place is also respectively provided with the first side piezoelectric patches group and/or the second side end piezoelectric patches group.

In the piezoelectric seismometer of the utility model, the crystal orientation of each side piezoelectric patches is<110>Direction, polarization electricity Field direction is parallel to its thickness direction, and residing transducing pattern is d31 transducing patterns.

In the piezoelectric seismometer of the utility model, upper end piezoelectric patches and lower end piezoelectricity that each piezoelectric patches group is included Piece is single layer structure, is made of piezoelectric monocrystal PMN-PT；Alternatively,

Multi-disc pressure is respectively adopted in whole or in part in upper end piezoelectric patches and lower end piezoelectric patches that each piezoelectric patches group is included The structure of electric monocrystalline, each each piezoelectric monocrystal for holding piezoelectric patches to be included respectively are attached by the arrangement of Crystal polarization direction respectively, Each piezoelectric monocrystal is made of piezoelectric monocrystal PMN-PT.

In the piezoelectric seismometer of the utility model, upper end piezoelectric patches and lower end piezoelectricity with multi-disc piezoelectric monocrystal Piece is realized using stacked piezoelectric patches.

In the piezoelectric seismometer of the utility model, the upper surface of each upper end piezoelectric patches and each lower end piezoelectric patches, under Upper surface electrode, lower surface electrode are respectively provided on surface, each upper surface electrode and each lower surface electrode are drawn output and led respectively Line；

The upper surface electrode of intermediate ends piezoelectric patches and each side piezoelectric patches piezoelectric patches, lower surface electrode electrode material be Silver or gold；The output lead drawn on each upper surface electrode, each lower surface electrode is copper wire.

The piezoelectric seismometer of the utility model has many advantages, such as high sensitivity, wide dynamic range, Portable durable, The application of the fields such as land seismic exploration, underground seam seismic exploration is more reliable and extensive.Relative to single-ended fixed cantilever beam Structure can be under conditions of equal length beam substrate using by the fixed mode of the both-end of simply supported beam substrate, the frequency of detection Range is more extensive, and used differential structure, compared to non-differential structure, anti-interference ability is stronger.

Description of the drawings

Below in conjunction with accompanying drawings and embodiments, the utility model is described in further detail, in attached drawing：

Fig. 1 is the structural schematic diagram of one preferred embodiment of piezoelectric seismometer provided by the utility model；

Fig. 2 is that novel PMN-PT piezoelectric materials are bent compared with sensitivity-frequency relation of PZT material under simple beam structure in Fig. 1 Line chart；

Fig. 3 is the structural schematic diagram of another embodiment of piezoelectric seismometer provided by the utility model.

Specific implementation mode

For a clearer understanding of the technical features, objectives and effects of the utility model, now control attached drawing is detailed Illustrate specific embodiment of the present utility model.

As shown in Figure 1, its structural schematic diagram for one preferred embodiment of piezoelectric seismometer of the utility model.The pressure Electric geophone, including simply supported beam substrate 2, piezoelectric patches 3, piezoelectric patches 5, mass block 4 and mass block 6, piezoelectric patches 3 and piezoelectric patches 5 form intermediate ends piezoelectric patches group, and mass block 4 and mass block 6 form mass block group.Simply supported beam substrate 2 uses elastic element, elasticity Element is more sensitive to shaking, and can increase the sensitivity of piezoelectric seismometer, can be preferably beryllium-bronze or phosphor bronze system At.Piezoelectric patches 3 is consistent with the piezoelectricity conversion performance of piezoelectric patches 5, and 3 lower surface of piezoelectric patches is pasted on the upper end of simply supported beam substrate 2, pressure 5 upper surface of electric piece is pasted on the lower end of simply supported beam substrate 2, and piezoelectric patches 3, piezoelectric patches 5 are respectively positioned on the half of simply supported beam substrate 2 At length, and about 2 setting symmetrical above and below of simply supported beam substrate, piezoelectric seismometer has the pedestal 1 being set on shell, letter Ends A end, the ends B on the length direction of strutbeam substrate 2 are rigidly connected in respectively with the shell that is rigidly connected on pedestal 1, at level Setting.The both ends of simply supported beam substrate 2 can be directly rigidly attached on shell in another embodiment of the utility model.Piezoelectric patches It is fixed on 3 upper surfaces using mass block 4 made of the alloys such as steel or tungsten, piezoelectric patches is fixed on 5 lower surface using steel or tungsten Mass block 6 made of equal alloys, mass block 4,6 mass of mass block are equal, and about the strain that piezoelectric patches can be made to generate bigger.It is right In different piezoelectric seismometers, the sensitive of wave detector is designed for different quality by the way that mass block 4, mass block 6 is arranged Degree and resonant frequency.4 bottom surface of mass block is identical as the upper surface size shape of piezoelectric patches 3, and the two is without the connection being staggered；Mass block 6 upper surfaces are identical as the lower surface size shape of piezoelectric patches 5, and the two is without the connection being staggered.Piezoelectric patches 3, piezoelectric patches 5 convert power For electric signal, piezoelectric patches 3, the upper surface of piezoelectric patches 5 are respectively provided with upper surface electrode and lower surface electrode on lower surface, it is each on Output lead, piezoelectric patches 3, piezoelectric patches 5 are drawn on surface electrode and lower surface electrode respectively.Upper surface electrode and lower surface electrode Electrode material silver, copper or gold may be used.What the output that the signal on piezoelectric patches 3 is formed was formed with the signal on piezoelectric patches 5 Output forms one group of differential wave, and piezoelectric patches 3, piezoelectric patches 5 connect output lead to export the differential wave.Piezoelectric patches 3, pressure Electric piece 5 is square shape single layer structure, and size 10mm*10mm*1mm is made, piezoelectric patches of piezoelectric monocrystal (PMN-PT) 3, the crystal orientation of piezoelectric patches 5 is<001>Direction, polarized electric field are oriented parallel to its thickness direction, and residing transducing pattern is D33 transducing patterns.

Fig. 2 is shown under simple beam structure, is computed, and the model that piezoelectric material is PMN-PT is in frequency in 0-1000Hz models It encloses the model sensitivity that interior piezoelectric material is PMN-PT and is integrally higher than the model that piezoelectric material is PZT-5A.Piezoelectric material is PMN- Sensitivity of the bimorph combination freely-supported beam model of PT within the scope of 0-1000Hz is 13.5-63.6mV/ms^-2, not only high The sensitivity of freely-supported beam model is combined in PZT-5A bimorphs, simultaneously above the central compressed knot that piezoelectric material is PMN-PT Structure model and single piezoelectric patches freely-supported beam model.This is because piezoresistive material is utilized in bimorph combined type simple beam structure at the same time The d of material₃₁And d₃₃Two kinds of transducing patterns.This shows to be substantially improved ground using PMN-PT as the sensitive material of geophone Shake the sensitivity of wave detector.

It is the structural schematic diagram of another embodiment of piezoelectric seismometer of the utility model with reference to figure 3.The piezoelectricity Shake wave detector, including simply supported beam substrate 2, piezoelectric patches 3, piezoelectric patches 5, piezoelectric patches 6, piezoelectric patches 7, piezoelectric patches 8, piezoelectric patches 9 and matter Gauge block 4, mass block 10, piezoelectric patches 3 and piezoelectric patches 9 form intermediate ends piezoelectric patches group, and piezoelectric patches 5 and piezoelectric patches 7 form left-hand end Piezoelectric patches group, piezoelectric patches 6 and piezoelectric patches 8 form right-hand end piezoelectric patches group, and mass block 4 and mass block 6 form mass block group.This reality Right-hand end piezoelectric patches group and left-hand end piezoelectric patches group have been different only in that it more with above-described embodiment with novel, piezoelectric patches 5 Consistent with 7 piezoelectricity conversion performance of piezoelectric patches and about 2 setting symmetrical above and below of simply supported beam substrate, piezoelectric patches 6 and 8 piezoelectricity of piezoelectric patches turn Transsexual energy is consistent and about 2 setting symmetrical above and below of simply supported beam substrate, and left-hand end piezoelectric patches group and right-hand end piezoelectric patches are set respectively Be placed in ends A end and the ends B in simply supported beam base length direction, piezoelectric patches 3, piezoelectric patches 5, piezoelectric patches 6, piezoelectric patches 7, piezoelectric patches 8, 9 upper and lower surface of piezoelectric patches is also plated with electrode respectively, distinguishes extraction wire on each electrode.The crystal orientation of piezoelectric patches 5,6,7 and 8 is< 110>Direction, polarized electric field are oriented parallel to its thickness direction, and residing transducing pattern is d31 transducing patterns；3 He of piezoelectric patches 9 crystal orientation is<001>Direction, polarized electric field are oriented parallel to its thickness direction, and residing transducing pattern is d33 transducing moulds Formula.In the present embodiment, one group of output, piezoelectric patches 7, pressure are formed after the Signal averaging that piezoelectric patches 3, piezoelectric patches 5, piezoelectric patches 6 acquire One group of output is formed after the Signal averaging that electric piece 8, piezoelectric patches 9 acquire, two groups export to form differential output, and the form of superposition can be with It is three current parallels or three Voltage Series.

It is all or part of in the upper end piezoelectric patches and lower end piezoelectric patches that are included in each piezoelectric patches group of the various embodiments described above Be respectively provided with multi-disc piezoelectric monocrystal, each each piezoelectric monocrystal for holding piezoelectric patches to be included respectively respectively by Crystal polarization direction arrange into Row connection, each piezoelectric monocrystal are made of piezoelectric monocrystal PMN-PT, and each upper end piezoelectric patches and lower end piezoelectric patches are equal in the present embodiment As a whole using the signal that piezoelectric monocrystal is acquired included in the realization of stacked piezoelectric patches and each upper end piezoelectric patches It is equal with above-mentioned single piezoelectric patches.

In another implementation of the utility model, intermediate ends piezoelectric patches both ends can only with a side piezoelectric patches, More side piezoelectric patches (being more than 3 groups) can be increased, as long as signal is overlapped.

The operation principle of the utility model；After piezoelectricity simply supported beam core is shaken by the earth, piezoelectricity simply supported beam can be with The earth vibration occurrence frequency and the identical vibration of amplitude, the intermediate ends of piezoelectricity simply supported beam are due to the effect of mass block, piezoelectric material Meeting stress deforms upon, since the direct piezoelectric effect of piezoelectric material can be converted mechanical energy into when piezoelectric material generates deformation Then electric energy acquires two piezoelectric patches power on signal, so that it may to obtain earthquake electric signal.It should be understood that above-mentioned Fig. 1, figure In embodiment shown by 3, can not also have above-mentioned mass block, core that can equally work normally；First side voltage Where piece and the second side terminal voltage piece will not necessarily be set to simply supported beam substrate at the left and right endpoint at end, the first side voltage piece The distance of endpoint with the second side terminal voltage piece apart from end where respective simply supported beam substrate is no more than the three of simply supported beam base length / mono- can preferable wave detector design requirement.

The utility model core is simple, and light weight is small, using the structure of single or more piezoelectric patches simply supported beams, It is applicable in low-frequency vibration environment, while having sensitivity with the raised feature of frequency, since seismic signal is in propagation Lossy in the process, the higher seismic wave of frequency amplitude in communication process is decayed bigger, can be compensated to a certain extent Earthquake wave amplitude increases the decaying generated with frequency.

Detector core body structure provided by the utility model is vibrated using the vibratory drive simple beam structure of local environment, So that piezoelectric patches generates Bending Deformation, make to generate effective electromotive force between the Different electrodes of piezoelectric patches, so as to make piezoelectricity more have The output energy of effect.

Detector core body structure provided by the utility model, has given full play to the anisotropy of piezoelectric monocrystal (PMN-PT) Can, take full advantage of the d of piezoelectric material₃₁And d₃₃Two kinds of transducing patterns.Set the electrode of piezoelectric patches to upper and lower surface electrode, Polarization direction and the direction (thickness direction) that is squeezed are consistent.Poisson effect when using piezoelectric patches from bending, more effectively The performance for playing piezoelectric patches, improves the energy delivery efficiency of piezoelectric patches.

Generally speaking, the geophone for providing core based on the utility model has high sensitivity, anti-interference energy The advantages that power is strong, wide dynamic range, Portable durable, in underground, the application of the fields such as seam seismic exploration, land seismic exploration is more It is reliable and extensive.

The embodiments of the present invention are described above in conjunction with attached drawing, but the utility model is not limited to The specific implementation mode stated, the above mentioned embodiment is only schematical, rather than restrictive, this field it is common Technical staff is not departing from the utility model aims and scope of the claimed protection situation under the enlightenment of the utility model Under, many forms can be also made, these are belonged within the protection of the utility model.

Claims (8)

1. a kind of piezoelectric seismometer, which is characterized in that include simply supported beam substrate, simply supported beam made of shell and elastic material Both ends on the length direction of substrate, which are rigidly attached to respectively on shell, to be horizontally disposed with, and is provided at least in simply supported beam substrate It is consistent and about the setting symmetrical above and below of simply supported beam substrate to all have piezoelectricity conversion performance in each piezoelectric patches group for one piezoelectric patches group Upper end piezoelectric patches and lower end piezoelectric patches, wherein being provided with intermediate ends piezoelectric patches at the half length of simply supported beam substrate Group, the output formed after the Signal averaging on all upper end piezoelectric patches and shape after the Signal averaging on all lower end piezoelectric patches At output form one group of differential wave, it is described differential to export that each upper end piezoelectric patches with each lower end piezoelectric patches connects output lead Signal；The crystal orientation of the intermediate ends piezoelectric patches is<001>Direction, polarized electric field is oriented parallel to its thickness direction, residing Transducing pattern is d33 transducing patterns.

2. piezoelectric seismometer according to claim 1, which is characterized in that the simply supported beam substrate be beryllium-bronze or Phosphor bronze is made.

3. piezoelectric seismometer according to claim 1, which is characterized in that also have a mass block group, the mass block group There are two the mass block identical in quality and setting symmetrical above and below of simply supported beam substrate, the two mass blocks to be respectively arranged at centre for tool On that face for holding the separate simply supported beam substrate of piezoelectric patches group upper end piezoelectric patches and lower end piezoelectric patches.

4. piezoelectric seismometer according to claim 1, which is characterized in that the both ends in simply supported beam base length direction Or wherein at one end is also respectively provided with the first side piezoelectric patches group and/or the second side end piezoelectric patches group.

5. piezoelectric seismometer according to claim 4, which is characterized in that the crystal orientation of each side piezoelectric patches is<110> Direction, polarized electric field are oriented parallel to its thickness direction, and residing transducing pattern is d31 transducing patterns.

6. according to claim 1-5 any one of them piezoelectric seismometers, which is characterized in that each piezoelectric patches group included Upper end piezoelectric patches and lower end piezoelectric patches are single layer structure, are made of piezoelectric monocrystal PMN-PT；Alternatively,

Multi-disc piezoelectricity list is respectively adopted in whole or in part in upper end piezoelectric patches and lower end piezoelectric patches that each piezoelectric patches group is included Brilliant structure, each each piezoelectric monocrystal for holding piezoelectric patches to be included respectively is attached by the arrangement of Crystal polarization direction respectively, each to press Electric monocrystalline is made of piezoelectric monocrystal PMN-PT.

7. piezoelectric seismometer according to claim 6, which is characterized in that the upper end piezoelectricity with multi-disc piezoelectric monocrystal Piece and lower end piezoelectric patches are realized using stacked piezoelectric patches.

8. according to any one of the claim 1-5 piezoelectric seismometers, which is characterized in that each upper end piezoelectric patches and each lower end Upper surface electrode, lower surface electrode, each upper surface electrode and each lower surface electricity are respectively provided on the upper surface of piezoelectric patches, lower surface Output lead is drawn respectively in pole；

The upper surface electrode of intermediate ends piezoelectric patches and each side piezoelectric patches piezoelectric patches, lower surface electrode electrode material be silver or Gold；The output lead drawn on each upper surface electrode, each lower surface electrode is copper wire.