CN204044114U - A kind of ring-shaped ultrasonic array energy transducer - Google Patents
A kind of ring-shaped ultrasonic array energy transducer Download PDFInfo
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- CN204044114U CN204044114U CN201420392198.8U CN201420392198U CN204044114U CN 204044114 U CN204044114 U CN 204044114U CN 201420392198 U CN201420392198 U CN 201420392198U CN 204044114 U CN204044114 U CN 204044114U
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Abstract
The utility model discloses a kind of ring-shaped ultrasonic array energy transducer, comprise shell and the ring piezoelectric crystal array be located in shell and acoustic resistance matching layer; Ring piezoelectric crystal array is rearranged by the spacing of multiple concentric ring piezoelectric crystal according to regulation; The upper and lower surface of ring piezoelectric crystal is connected to electrode, and the ring piezoelectric crystal of connecting electrode is unit of shaking; Electrode towards concrete NDT face is located on acoustic resistance matching layer, is provided with pad absorbent treatment dorsad between the electrode in concrete NDT face and shell.It is not enough that the utility model ring-shaped ultrasonic array energy transducer overcomes metasystem lateral resolution of singly shaking, the less annular array transducer of first number that shakes is adopted to form high-resolution focusing acoustic field, to the detecting and identifying of pumping of prostressed duct quality high lateral resolution, improve and detect noise acoustic ratio and sensitivity.
Description
Technical field
The utility model belongs to ultrasonic non-destructive inspection techniques field, is specifically related to a kind of ring-shaped ultrasonic array energy transducer.
Background technology
In prestressed reinforced concrete construction, pumping of prostressed duct quality directly affects integrally-built load-bearing capacity and permanance, is a problem of engineering staff's general concern to the effective detection in pipeline pneumatic mortar quality ground.Supercritical ultrasonics technology is adopted to detect pumping of prostressed duct quality identical with the ultimate principle detecting defect in concrete, utilize the characterisitic parameter that Ultrasonic logging method or ultrasonic pulse-echo method acquisition ultrasound wave are propagated in concrete, as the velocity of sound, wave amplitude, frequency, judge concrete quality by the change of these parameters.
The composite material that concrete is made up of cement, sand, coarse aggregate, when ultrasound wave is propagated in concrete, acoustic beam is reflected, scattering and absorption, and ultrasonic energy decay is large, penetration depth is little, and exponentially decays along with the raising of frequency.Traditional ultrasonic nondestructive testing device generally adopts first transducer that singly shakes, and select lower frequency of operation, such device lateral resolution is poor, only can detect the mud jacking defect of decimeter grade, and defect location is more difficult, comes with some shortcomings.In order to improve detection lateral resolution, the high frequency waves that frequency is high, beam directional is good should be selected.Therefore, in pumping of prostressed duct quality testing, high lateral resolution and large investigation depth define contradiction.
So people consider sound beam focusing technology, the ultrasonic beam that transducer is launched converges within the specific limits, and because acoustic beam converges, its penetration power and echo are strengthened, and improve detection sensitivity, resolution is also improved.At present, phased-array technique is usually adopted to carry out electron focusing.Phase array transducer mainly contains linear array, two-dimensional array and Annular Phased Arrays etc.Ultrasonic phased array technology has been widely used in the fields such as biomedical, and applies less in concrete NDT.
The complete rotational symmetry of Annular Phased Arrays sound field, has superior axial focusing ability.Annular Phased Arrays can when first number that shakes be less than linear array and face array transducer shake first number form high-resolution focusing acoustic field, reduce the cost of manufacture because number of channels too much brings, simplify circuit and control system simultaneously.Therefore, by Annular Phased Arrays transducer application in pumping of prostressed duct quality testing, the resolution and sensitivity that detect can be improved.
Summary of the invention
In view of the foregoing defects the prior art has, the utility model provides a kind of ring-shaped ultrasonic array energy transducer, the detecting and identifying of high-resolution focusing acoustic field to pumping of prostressed duct quality high lateral resolution can be formed, detect noise acoustic ratio and sensitivity to improve.
A kind of ring-shaped ultrasonic array energy transducer, comprises shell and the ring piezoelectric crystal array be located in shell and acoustic resistance matching layer; Described ring piezoelectric crystal array is rearranged according to the spacing of regulation by the ring piezoelectric crystal that multiple (being generally 4 ~ 8) is concentric; The upper and lower surface of described ring piezoelectric crystal is connected to electrode, and the ring piezoelectric crystal of connecting electrode is unit of shaking; Electrode towards concrete NDT face is located on acoustic resistance matching layer, is provided with pad absorbent treatment dorsad between the electrode in concrete NDT face and shell.
The delay pulse signal that the unit's reception external unit that respectively shakes provides, and convert this signal to ultrasonic signal, the incident concrete of ultrasonic signal of generation, being embedded in the not full position reflection of the pumping of prostressed duct in concrete in advance, forms echoed signal; Unit of respectively shaking receives echoed signal, and exports after converting echoed signal to electric signal.
Described ring piezoelectric crystal adopts piezoelectric ceramics.
The thickness of described ring piezoelectric crystal is λ/2, and the thickness of described acoustic resistance matching layer is the odd-multiple of λ/4, and λ is ultrasound wave wavelength.
Described electrode is welded with wire, for transmission of electric signals.
Described pad sound absorbing material layer adopts epoxy resin to add tungsten powder to coordinate and form, or adopts ferrite powder to add rubber powder to coordinate and form.
Described shell is used for fixing of energy converter inner member and protects inner member, acoustics will be had to isolate, can adopt elastomeric material, prevent case vibration from causing signal disturbing between inner member and housing.
In order to reduce the signal wire that transducer is connected with external unit, described unit of shaking is connected with electronic switch.
In emission process, unit of respectively shaking is encouraged by certain sequential, the wave front that the ultrasonic signal superposition formation one that the unit that makes respectively to shake launches is new, realizes transmitting focusing; In receiving course, according to the phase differential existed between the echoed signal of respectively shaking received by unit, phase shift synthesis is carried out to the electric signal that unit of respectively shaking exports, realizes collectiong focusing.
In emission process, by changing configuration time delay of delay pulse signal, focal length is made to change with time delay and change; In receiving course, according to the distance of ultrasonic echo, corresponding receive delay is dropped into successively to the electric signal that unit of respectively shaking exports, realizes dynamic focusing.In actual applications, focal length can be selected, without the need to changing ring-shaped ultrasonic array energy transducer according to the buried depth of prestress pipe.
In order to improve near field region lateral resolution, adopting and becoming aperture technique: to shake unit in the near field place inner ring that less input, ring-shaped ultrasonic array energy transducer is with less Aperture receiving echoed signal; Outer shroud of suitably increasing input at far field place shakes unit, and ring-shaped ultrasonic array energy transducer is with larger Aperture receiving echoed signal.
Hinge structure, the utility model has following Advantageous Effects:
(1) the utility model ring-shaped ultrasonic array energy transducer overcomes metasystem lateral resolution deficiency of singly shaking, the less annular array transducer of first number that shakes is adopted to form high-resolution focusing acoustic field, to the detecting and identifying of pumping of prostressed duct quality high lateral resolution, improve and detect noise acoustic ratio and sensitivity.
(2) the utility model ring-shaped ultrasonic array energy transducer is formed and assembles sound field, and acoustic energy is concentrated, and in concrete, propagation distance is far away, thus adds detection depth range.
(3) the utility model ring-shaped ultrasonic array energy transducer is by delay of control, and can realize sound field dynamic focusing, focus can automatically adjust, without the need to changing transducer according to the buried depth of prestress pipe in reality.
(4) the utility model ring-shaped ultrasonic array energy transducer structure is simple, and system cost is low, suitable with tradition first transducer pick-up unit cost that singly shakes.
Accompanying drawing explanation
Fig. 1 is the structural representation of the utility model ring-shaped ultrasonic array energy transducer.
Fig. 2 is the cross-sectional view of the utility model ring piezoelectric crystal array.
Fig. 3 is the focusing schematic diagram of the utility model ring-shaped ultrasonic array transducer.
Fig. 4 is the dynamic focusing schematic diagram of the utility model ring-shaped ultrasonic array transducer.
Fig. 5 is the schematic diagram that the utility model ring-shaped ultrasonic array transducer becomes Aperture receiving echoed signal.
Embodiment
In order to more specifically describe the utility model, below in conjunction with the drawings and the specific embodiments, the technical solution of the utility model is described in detail.
Fig. 1 is the structural map of ring-shaped ultrasonic array energy transducer, and it forms primarily of ring piezoelectric crystal array 1, acoustic resistance matching layer 2, electrode 3, pad absorbent treatment 4, wire 5 and shell 6.
In present embodiment, ring piezoelectric crystal array is arranged by the spacing of 4 separate annular concentric piezoelectric crystals according to regulation, piezoelectric crystal is compound substance, general employing piezoceramic material, for electric pulse being converted to the mechanical vibration of ultrasonic frequency, and the mechanical vibration receiving echo convert electric signal to, the thickness of piezoelectric crystal gets 1/2 of ultrasonic wavelength X.
The upper and lower surface of each piezoelectric crystal connects positive and negative electrode respectively, and connecting the piezoelectric crystal of positive and negative electrode and be called that annular is shaken unit, is the primary element forming ultrasonic transducer.
Piezoelectric vibrating element front end, is namely provided with acoustic resistance matching layer towards side, concrete NDT face, should select the material insulated, attenuation coefficient is low and wear-resisting.Its effect is not worn for the protection of piezoelectric vibrating element on the one hand; On the other hand, the transmission as much as possible of ultrasonic beam energy is made to enter xoncrete structure.The physical dimension of acoustic resistance matching layer and the necessary Satisfying Matching Conditions of acoustic impedance, thickness gets the odd-multiple of 1/4 ultrasonic wavelength, and its acoustic impedance Z2 meets following formula:
In formula: Z
1for the acoustic impedance of piezoelectric crystal material, Z
3for the acoustic impedance of concrete material.
Because piezoelectric crystal launches ultrasound wave to two ends, need overleaf to add and use pad absorbent treatment, acoustic absorbant is generally epoxy resin and adds tungsten powder or ferrite powder and add rubber powder and coordinate and form, for the ultrasonic energy of attenuation and absorption piezoelectric crystal backward radiation, make it not at the inner roundtrip of transducer.
Shell is used for the inner member of fixing of energy converter, and protects inner member.Acoustics to be had between inner member and shell to isolate, elastomeric material can be adopted to isolate, with the interference preventing case vibration from making pair signals.
Fig. 2 is the schematic cross-section of ring-shaped ultrasonic array transducers with 4 units of shaking, and each annulus adopts with one heart, the design proposal of homalographic, and electrical impedance, the sensitivity of the unit that ensures respectively to shake are close.
Ensureing under the prerequisite that transducer dimensions is certain, when first number that shakes is few, the single elemental area that shakes is large, and shaking between unit, interference is little mutually, but the amplitude of secondary lobe also strengthens; Shake first increased number time, shake between unit and mutually disturb increasing, increase the complicacy of control circuit and instability.Therefore, according to testing requirement and condition, ring-shaped ultrasonic array transducer can be designed to 4 ~ 8 annulus shake unit different series.
First spacing of shaking is too small, shakes between unit and mutually disturbs increase, and makes troubles to the processing and fabricating of transducer; When first spacing of shaking is greater than half-wavelength, near field region sound field fluctuation aggravates, and first spacing of shaking is excessive, and transducer dimensions can be caused to increase.Therefore, it is proper that first spacing of shaking is less than 1/2 wavelength.
The parameter of present embodiment ring piezoelectric crystal array (4 units of shaking) is as shown in table 1:
Table 1
The selection of ring-shaped ultrasonic array transducer frequency of operation, should according to different investigation depth, and the requirement of lateral resolution makes one's options.Frequency is higher, and wavelength is shorter, then beam directional is better, and transverse resolution is high, but the increase that decay is also proportional, investigation depth is reduced, and signal to noise ratio (S/N ratio) is affected.Therefore, should select lower frequency of operation, present embodiment frequency of operation is between 50kHz and 250kHz.
Fig. 3 gives ring-shaped ultrasonic array transducer electron focusing schematic diagram, and ultrasonic phase array detection technique realizes in respectively the shake delay of first signal of accurate control, is the core technology during ultrasonic phase array detects.
Each annular shakes unit when being encouraged by the pulse signal of same frequency, the sound wave produced is coherent wave, in space, the acoustic pressure amplitude of some points is enhanced because of sound wave in-phase stacking, and the acoustic pressure amplitude of other points weakens due to the anti-phase counteracting of sound wave, thus forms stable ultrasonic field in space.
Consider the position that the ultrasonic beam that each crystal array unit launches is F at axial focusing in distance, i.e. focus O, for the ultrasound wave making each array element launch arrives focus O simultaneously, first to calculate the distance between focus and each crystal unit, according to the range difference calculated, and the velocity of propagation of ultrasound wave in this concrete medium, control the time delay being applied to each unit.The high-voltage pulse signal excitation that firing pulse generator produces time delay different is shaken unit accordingly, accurately controls the different ultrasonic signal shaking unit and arrives target focus point O simultaneously, obtains maximum acoustic beam signal in focus O first acoustic beam superposition of respectively shaking.
Receiving course is the inverse process of emission process; First target focus point is set, external reception device arrives different unit of shaking mistiming according to target focus point O carries out accurate time delay to the shake echoed signal of unit of difference, the echoed signal addition making difference shake first, obtains larger echo signal amplitude by the concentration of energy of multi-path echo signal.
Usually the reflected signal meeting delay requirement on sound path just can be focused and be strengthened.And for some random reflected undesired signal and noise, because be not according to the reflection of specific reflection rule, be not applied, therefore, useful reflected signal can be strengthened, and undesired signal is suppressed, improves signal to noise ratio (S/N ratio).
In reality detects, prestress pipe buried depth is different, is change with the distance D of transducer, at this moment, change the time delay of each annulus, make focal length F always equal D, radiated sound field always focuses on prestress pipe buried depth place, namely realizes dynamic focusing, as shown in Figure 4.By controlling time delay that each unit of shaking transmits and amplitude carries out scanning imagery, carrying out dynamic focusing, not needing to change the pumping of prostressed duct quality testing that transducer just can realize different buried depth.
Employing is shaken element array combined transmit and reception, increases sound source aperture, improves far field resolution, but increases along with aperture, and the diameter of acoustic beam also increases near field region, and the lateral resolution near field is declined.For this problem, adopt and change the resolution that aperture technique obtains closely, far field is good, as shown in Figure 5.When the detection of a target is nearer, center disk and less annulus unit of shaking is adopted to receive the echoed signal near field, to improve the lateral resolution of near field region, along with the detection of a target degree of depth increases, increase outer toroid unit of shaking and receive far field echoed signal, to improve far field lateral resolution.
In addition, present embodiment can also to be shaken first transmission and reception signal by the single disk of Support center under the condition not changing soft and hardware, and namely singly shake first transducer detecting pattern.
Be explained above embodiment of the present utility model, just exemplarily, in the scope not departing from the utility model main idea, can carry out omitting, increase, change, implement by other means, these variations also should be considered as in protection domain of the present utility model.
Claims (5)
1. a ring-shaped ultrasonic array energy transducer, is characterized in that: comprise shell and the ring piezoelectric crystal array be located in shell and acoustic resistance matching layer; Described ring piezoelectric crystal array is rearranged by the spacing of multiple concentric ring piezoelectric crystal according to regulation; The upper and lower surface of described ring piezoelectric crystal is connected to electrode, and the ring piezoelectric crystal of connecting electrode is unit of shaking; Electrode towards concrete NDT face is located on acoustic resistance matching layer, is provided with pad absorbent treatment dorsad between the electrode in concrete NDT face and shell.
2. ring-shaped ultrasonic array energy transducer according to claim 1, is characterized in that: described ring piezoelectric crystal adopts piezoelectric ceramics.
3. ring-shaped ultrasonic array energy transducer according to claim 1, is characterized in that: the thickness of described ring piezoelectric crystal is λ/2, and the thickness of described acoustic resistance matching layer is the odd-multiple of λ/4, and λ is ultrasound wave wavelength.
4. ring-shaped ultrasonic array energy transducer according to claim 1, is characterized in that: described electrode is welded with wire.
5. ring-shaped ultrasonic array energy transducer according to claim 1, is characterized in that: described unit of shaking is connected with electronic switch.
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| CN201420392198.8U CN204044114U (en) | 2014-07-16 | 2014-07-16 | A kind of ring-shaped ultrasonic array energy transducer |
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Cited By (12)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN105726059A (en) * | 2014-12-26 | 2016-07-06 | 三星麦迪森株式会社 | Probe and manufacturing method thereof |
| CN107470116A (en) * | 2017-08-14 | 2017-12-15 | 太仓宏微电子科技有限公司 | A kind of high frequency ultrasound array energy transducer and preparation method based on MEMS technology |
| CN108837305A (en) * | 2018-05-15 | 2018-11-20 | 清华大学 | Flexible pacemaker and bioelectricity monitoring method based on flexible pacemaker |
| CN109759307A (en) * | 2018-12-28 | 2019-05-17 | 钢研纳克检测技术股份有限公司 | A kind of electromagnetic acoustic phase array transducer of focus adjustable |
| CN110090364A (en) * | 2019-04-30 | 2019-08-06 | 四川省人民医院 | A kind of adherent rechargeable ultrasonic positive inotropic therapeutic device |
| CN111119839A (en) * | 2018-11-01 | 2020-05-08 | 中国石油化工股份有限公司 | While-drilling ultrasonic probe assembly and while-drilling ultrasonic detection method |
| CN112179992A (en) * | 2020-09-25 | 2021-01-05 | 广州多浦乐电子科技股份有限公司 | Central self-focusing circular array probe |
| CN112414601A (en) * | 2020-11-18 | 2021-02-26 | 北京理工大学 | Wide frequency ultrasonic transducer |
| CN112657817A (en) * | 2020-11-20 | 2021-04-16 | 深圳先进技术研究院 | Array type ultrasonic transducer and manufacturing method thereof |
| CN113900287A (en) * | 2021-10-27 | 2022-01-07 | 合肥工业大学 | Acousto-optic modulator |
| CN114768907A (en) * | 2022-04-12 | 2022-07-22 | 深圳欢影医疗科技有限公司 | Ultrasonic liquid transfer method and system based on annular array ultrasonic transducer |
| WO2023019554A1 (en) * | 2021-08-20 | 2023-02-23 | 深圳先进技术研究院 | Multi-frequency ultrasonic transducer, ultrasonic imaging system having same, and ultrasonic imaging method |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN105726059A (en) * | 2014-12-26 | 2016-07-06 | 三星麦迪森株式会社 | Probe and manufacturing method thereof |
| CN105726059B (en) * | 2014-12-26 | 2021-05-04 | 三星麦迪森株式会社 | Probe and method of manufacturing the same |
| CN107470116A (en) * | 2017-08-14 | 2017-12-15 | 太仓宏微电子科技有限公司 | A kind of high frequency ultrasound array energy transducer and preparation method based on MEMS technology |
| CN108837305B (en) * | 2018-05-15 | 2021-04-13 | 清华大学 | Flexible pacemaker and bioelectricity monitoring method based on flexible pacemaker |
| CN108837305A (en) * | 2018-05-15 | 2018-11-20 | 清华大学 | Flexible pacemaker and bioelectricity monitoring method based on flexible pacemaker |
| CN111119839A (en) * | 2018-11-01 | 2020-05-08 | 中国石油化工股份有限公司 | While-drilling ultrasonic probe assembly and while-drilling ultrasonic detection method |
| CN109759307A (en) * | 2018-12-28 | 2019-05-17 | 钢研纳克检测技术股份有限公司 | A kind of electromagnetic acoustic phase array transducer of focus adjustable |
| CN109759307B (en) * | 2018-12-28 | 2023-11-21 | 钢研纳克检测技术股份有限公司 | Electromagnetic ultrasonic phased array transducer with adjustable focal length |
| CN110090364A (en) * | 2019-04-30 | 2019-08-06 | 四川省人民医院 | A kind of adherent rechargeable ultrasonic positive inotropic therapeutic device |
| CN110090364B (en) * | 2019-04-30 | 2021-12-21 | 四川省人民医院 | Wall-attached charging type ultrasonic positive inotropic treatment device |
| CN112179992A (en) * | 2020-09-25 | 2021-01-05 | 广州多浦乐电子科技股份有限公司 | Central self-focusing circular array probe |
| CN112414601A (en) * | 2020-11-18 | 2021-02-26 | 北京理工大学 | Wide frequency ultrasonic transducer |
| CN112414601B (en) * | 2020-11-18 | 2021-10-26 | 北京理工大学 | Wide frequency ultrasonic transducer |
| CN112657817A (en) * | 2020-11-20 | 2021-04-16 | 深圳先进技术研究院 | Array type ultrasonic transducer and manufacturing method thereof |
| CN112657817B (en) * | 2020-11-20 | 2022-03-04 | 深圳皓影医疗科技有限公司 | Array type ultrasonic transducer and manufacturing method thereof |
| WO2023019554A1 (en) * | 2021-08-20 | 2023-02-23 | 深圳先进技术研究院 | Multi-frequency ultrasonic transducer, ultrasonic imaging system having same, and ultrasonic imaging method |
| CN113900287A (en) * | 2021-10-27 | 2022-01-07 | 合肥工业大学 | Acousto-optic modulator |
| CN114768907A (en) * | 2022-04-12 | 2022-07-22 | 深圳欢影医疗科技有限公司 | Ultrasonic liquid transfer method and system based on annular array ultrasonic transducer |
| CN114768907B (en) * | 2022-04-12 | 2024-03-12 | 深圳欢影医疗科技有限公司 | Ultrasonic pipetting method and system based on annular array ultrasonic transducer |
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