CN1263345C - Underground sound sensitive sensor - Google Patents
Underground sound sensitive sensor Download PDFInfo
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- CN1263345C CN1263345C CN 02159452 CN02159452A CN1263345C CN 1263345 C CN1263345 C CN 1263345C CN 02159452 CN02159452 CN 02159452 CN 02159452 A CN02159452 A CN 02159452A CN 1263345 C CN1263345 C CN 1263345C
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Abstract
The present invention relates to an underground sound sensitive sensor which is composed of a physical resonant cavity, a resonant chip, a thimble, a piezoelectric ceramic chip, an electric signal amplifier, conducting wires, a circuit box and an audio signal output terminal, wherein the top surface of the physical resonant cavity is provided with the resonant chip, and the thimble is welded to the center of the resonant chip. The tip part of the thimble contacts the piezoelectric ceramic chip fixed in the physical resonant cavity by the conducting wires from four directions. The anode and the cathode of the piezoelectric ceramic chip are connected with the signal input terminal and the ground terminal of the electric signal amplifier by two conducting wires. The electric signal amplifier is arranged in the circuit box, and the circuit box arranged at the bottom of the physical resonant cavity is provided with the audio signal output terminal. When the sensor is embedded in a position of 20 centimeters underground, weak sound signals in the range of the ground (with the radius of 20 meters) and underground positions (with the radius of 30 meters), and the signals are outputted as analog signals after magnification. The sensor has the advantages of high sensitivity, corrosion prevention and moisture protection, and can stably and reliably work in various kinds of soil and media. Because of strong invisibility and strong damage resistance, the sensor is especially suitable for the security technology precaution of field and special environment.
Description
Technical field
The present invention relates to a kind of security precautions technology equipment, specifically a kind of underground acoustic sensor.
Background technology
Open-air safety technological guard difficulty maximum be disguise and anti-destructive, existing security protection equipment can't be used by the restriction of above-mentioned factor.Conventional sound-detection gear relies on air borne, and well-known, sound is a kind of compressional wave in air, and at this moment the direction of vibration of medium particle is corresponding to the direction of transfer of sound wave.Sound will produce phenomenons such as reflection, refraction and diffraction in the air, and cause decay in the air.These decay generally include acoustic energy and propagate the decay Aa that the decay Ad cause and absorption of air cause with dispersing of distance, and ground absorbs the decay Ag that causes, the decay Am that decay Ab that barrier causes and meteorological condition cause etc.Total decay A then is the summation of various decay: A=Ad+Aa+Ag+Ab+Am.The sound barrier decay underground as it is embedded in, that the stratum constitutes, ground absorbs in addition, can't hear face of land sound.We can analyze like this, and Fig. 1 is embedded in underground schematic diagram for conventional space pick-up, and sound wave arrival ground is passed the stratum and is transmitted to pick-up.Because pick-up is media by air vibration, thus can only receive transmitted wave, and transmitted wave on the stratum with acoustic pressure on the pick-up interface with the acoustic pressure ratio of incident wave on the ground surface and interface is:
Define according to transaudient damage:
Wherein
Usually the characteristic impedance on stratum is much larger than the characteristic impedance of air, the mass law of sound transmission loss: TL=20Lg (ω m/2 ρ 1c1)---------------(4) again
Show: the common logarithm of the quality of sound transmission loss amount and unit are is directly proportional.The mass area ratio on stratum is big more, and the sound transmission loss amount is just big more, and m doubles, and the sound transmission loss amount increases 6dB, and (4) formula is also represented: frequency is high more, and the sound transmission loss amount is just big more, and frequency doubles, and the sound transmission loss amount also increases 6dB.ω in the formula=2 π f, ρ c are airborne characteristic impedance ≈ 400.Formula (4) also can be expressed as:
TL＝20Lgm+20Lgf-42.5-----------(5)
Following formula is the Theoretical Calculation result of sound wave vertical incidence.When the irregular incident of sound wave, then tackle all incidence angles and ask on average, empirical equation, transaudient attenuation is:
TL＝18.5Lg(mf)-47.5-------------------------(6)
This shows that it is very faint that the space pick-up is embedded in the underground sound intensity that receives.
In order to address the above problem, the invention provides a kind of underground acoustic sensor, it adopts the physics resonant cavity, receiving plane and ground are combined together, be considered as same interface, rely on solid vibration propagation energy, owing in solid is propagated, both there had been the compressional wave of sound wave, also have shear wave, Propagation of Energy is much larger than air, and just the solid-borne sound transmission of often saying has characteristics such as propagation velocity is fast, decay is few.Underground 20cm place can detect in the radius 20cm of the face of land this underground acoustic sensor and underground 30cm or farther faint voice signal imbedding.Succeeding in developing of this transducer is for open-air safety precaution field provides effective technical means.
Summary of the invention
Underground acoustic sensor of the present invention is made up of physics resonant cavity 11, resonance piece 12, thimble 13, piezoelectric ceramic piece 14, electric signal amplifier 15, lead 16, circuit box 17 and audio signal output end 18; Physics resonant cavity 11 is cylindrical stainless steel cylinder, end face at physics resonant cavity 11 is provided with resonance piece 12, central part at resonance piece 12 welds a thimble 13, the tip of thimble 13 contacts with piezoelectric ceramic piece 14, piezoelectric ceramic piece 14 is fixed in the physics resonant cavity 11 from four direction by steel wire, piezoelectric ceramic piece 14 just, negative pole joins by the signal input part and the ground end of two leads 16 with electric signal amplifier 15, electric signal amplifier 15 places in the circuit box 17, circuit box 17 is arranged on the bottom of physics resonant cavity 11, on circuit box 17, be provided with audio signal output end 18, it is characterized in that the circuit of described electric signal amplifier 5 is by field effect transistor 2SK30A, triode 2SA733, amplifier NE5532, resistance R 1～R10, capacitor C 1～C7 forms; Annexation is: input IN connects an end of capacitor C 1, the other end of capacitor C 1 connects an end of resistance R 1 and the G end of field effect transistor 2SK30A, the D end of field effect transistor 2SK30A connects the base stage b of triode 2SA733 and an end of resistance R 2, the other end of resistance R 2 connects an end of resistance R 5 and the positive pole of capacitor C 2, the minus earth of capacitor C 2, the S end of field effect transistor 2SK30A connects an end of resistance R 3 and the positive pole of capacitor C 3, one end of the negative pole of the other end of resistance R 3 and capacitor C 3 and resistance R 6 and an end of resistance R 4, the other end of resistance R 1 is connected, the other end ground connection of resistance R 4, the emitter e of triode 2SA733 connects an end of resistance R 7 and the negative pole of capacitor C 4, the other end of resistance R 7 links to each other with the positive pole of capacitor C 4, the power end 8 that also connects simultaneously 12V power supply and amplifier NE5532, the collector electrode c of triode 2SA733 connects the positive pole of capacitor C 5, one end of resistance R 8 and the in-phase input end 3 of amplifier NE5532, the negative pole of capacitor C 5 connects the other end of resistance R 6, the other end ground connection of resistance R 8, be connected in series a resistance R 9 between the inverting input 2 of amplifier NE5532 and the output 1, the 4 end ground connection of amplifier NE5532, one end of resistance R 9 is connected with an end of resistance R 10, the other end of resistance R 10 links to each other with the positive pole of capacitor C 6, the minus earth of capacitor C 6, another in-phase input end 5 of the output 1 and its of amplifier NE5532 is connected, its another inverting input 6 is connected with output 7, output 7 connects the positive pole of capacitor C 7, and the negative pole of capacitor C 7 is output OUT.
Underground acoustic sensor of the present invention, its advantage is: propagate that speed of sound is fast, decay less, highly sensitive, the transmission of its sound wave is to come Propagation of Energy by the momentum transfer between adjacent particle.When sound wave incides ground, when causing the resonance piece vibration by the momentum transfer between adjacent particle, the Fi of resonance piece each point arrives piezoelectric patches by thimble, and the stressed FM of M point of piezoelectric patches is: each point be delivered to top vector and, be formulated as:
FM＝∑Fi---------------------(7)
This shows, though arrive the sound on the face of land or the sound that transmits by the stratum very faint, behind resonant cavity, obtain amplifying, the signal of telecommunication of piezoelectric patches output amplifies the back through amplifier and exports.Underground acoustic sensor of the present invention improves thousands of times approximately than the sensitivity of conventional piezoelectric type resonance microphone.
Description of drawings
Fig. 1 is the schematic diagram that is embedded in underground conventional pick-up,
Fig. 2 is the three-dimensional exploded view of the underground acoustic sensor of the present invention,
Fig. 3 is the circuit diagram of the electric signal amplifier of the underground acoustic sensor of the present invention.
Number in the figure is as follows:
21 stratum, 22 conventional pick-up 11 physics resonant cavitys 12 resonance pieces 13 thimbles 14 piezoelectric ceramic pieces 15 electric signal amplifiers 16 leads 17 circuit box 18 audio signal output ends
Electric elements are as follows:
Field effect transistor: type ZSK30A triode: model ZSA733 amplifier: model NE5532
Resistance: R1 resistance 1M, R2 resistance 10K, R3 resistance 2K, R4 resistance 680 Ω, R5 resistance 2.2K, R6 resistance 27K, R7 resistance 560 Ω, R8 resistance 5.6K, R9 resistance 100K, R10 resistance 5.1K
Electric capacity: C1 is 104, and C2, C6 are 100VF/25V, and C3 is 47VF/25V, and C4, C5, C7 are 10VF/25F
Embodiment
Referring to Fig. 2, underground acoustic sensor of the present invention is made up of physics resonant cavity 11, resonance piece 12, thimble 13, piezoelectric ceramic piece 14, electric signal amplifier 15, lead 16, circuit box 17 and audio signal output end 18; Physics resonant cavity 11 is cylindrical stainless steel cylinder (φ 74 * 109 * 0.22 wall thickness mm), the end face of physics resonant cavity 11 has resonance piece 12 (φ 74 * 0.22 wall thickness mm), (φ 0.7 * 15mm) to weld a thimble 13 at the central part of resonance piece 12, (φ 35 for the tip of thimble 13 and piezoelectric ceramic piece 14, frequency response 1.8-2.2KHz) contacts, (φ 0.18 * 37mm) is fixed on the cylindrical stainless steel cylinder that constitutes physics resonant cavity 11 with four steel wires from four direction with piezoelectric ceramic piece 14, piezoelectric ceramic piece 14 just, negative pole joins by the signal input part and the ground end of two leads 16 (φ 0.013mm * 7 cores) with electric signal amplifier 15, electric signal amplifier 15 places in the circuit box 17, circuit box 17 is arranged on the bottom of physics resonant cavity 11, is provided with audio signal output end 18 on circuit box 17.
The present invention combines cavity resonant technology and piezo technology, at first sound is strengthened amplifying with physical method, amplifies by carrying out secondary after the electromechanics conversion, and exports in signal of telecommunication mode, has solved this key technology.
Fig. 3 has represented the operation principle of electric signal amplifier 15: can obtain the high circuit of supply voltage utilance with series connection N channel field-effect pipe (2SK30A) and triode (2SA733), resistance R1 (1M) has determined dc point, and the collector voltage that makes V2 (2SA733) is Vcc/2, the open circuit multiplication factor of V1 (2SK30A) is about 5 times, because the emitter resistance of V2 (2SA733) is 560 Ω, collector load is 5.6K Ω, so its open circuit multiplication factor is about 10 times, total magnification is 50 times (34dB), because negative feedback also is 32dB, therefore, it is little to obtain distorted signals, characteristics such as bandwidth.Amplifier NE5532 multiplication factor is about 20 times, so the circuit overall gain is about 58dB.
Buried acoustic sensor technical parameter is as follows:
Supply voltage: DC12V-15V; Operating current :≤5mA; Frequency response: 100Hz-8KHz;
The distortion factor :≤0.1%;
Sensitivity (sound intensity value):
Voice (can not hear) :≤5dB/1m
Strike ground (can not hear) :≤1dB/1m
The monitoring scope:
The zone can not heard in ground: a diameter 40m/1 pick-up
But underground monitored area: diameter 80m (conventional soil property)/1 pick-up
Ambient temperature :-25 ℃-+40 ℃; Relative humidity: 100%RH; Waterproof, anticorrosion
Claims (1)
1. a underground acoustic sensor is made up of physics resonant cavity (11), resonance piece (12), thimble (13), piezoelectric ceramic piece (14), electric signal amplifier (15), lead (16), circuit box (17) and audio signal output end (18); Physics resonant cavity (11) is cylindrical stainless steel cylinder, end face at physics resonant cavity (11) is provided with resonance piece (12), central part at resonance piece (12) welds a thimble (13), the tip of thimble (13) contacts with piezoelectric ceramic piece (14), piezoelectric ceramic piece (14) is fixed in the physics resonant cavity (11) from four direction by steel wire, piezoelectric ceramic piece (14) just, negative pole joins by the signal input part and the ground end of two leads (16) with electric signal amplifier (15), electric signal amplifier (15) places in the circuit box (17), circuit box (17) is arranged on the bottom of physics resonant cavity (11), on circuit box (17), be provided with audio signal output end (18), it is characterized in that the circuit of described electric signal amplifier (15) is by field effect transistor 2SK30A, triode 2SA733, amplifier NE5532, resistance R 1～R10, capacitor C 1～C7 forms; Annexation is: input IN connects an end of capacitor C 1, the other end of capacitor C 1 connects an end of resistance R 1 and the G end of field effect transistor 2SK30A, the D end of field effect transistor 2SK30A connects the base stage b of triode 2SA733 and an end of resistance R 2, the other end of resistance R 2 connects an end of resistance R 5 and the positive pole of capacitor C 2, the minus earth of capacitor C 2, the S end of field effect transistor 2SK30A connects an end of resistance R 3 and the positive pole of capacitor C 3, one end of the negative pole of the other end of resistance R 3 and capacitor C 3 and resistance R 6 and an end of resistance R 4, the other end of resistance R 1 is connected, the other end ground connection of resistance R 4, the emitter e of triode 2SA733 connects an end of resistance R 7 and the negative pole of capacitor C 4, the other end of resistance R 7 links to each other with the positive pole of capacitor C 4, the power end (8) that also connects simultaneously 12V power supply and amplifier NE5532, the collector electrode c of triode 2SA733 connects the positive pole of capacitor C 5, the in-phase input end (3) of one end of resistance R 8 and amplifier NE5532, the negative pole of capacitor C 5 connects the other end of resistance R 6, the other end ground connection of resistance R 8, be connected in series a resistance R 9 between the inverting input of amplifier NE5532 (2) and the output (1), (4) end of amplifier NE5532 is earth terminal, one end of resistance R 9 is connected with an end of resistance R 10, the other end of resistance R 10 links to each other with the positive pole of capacitor C 6, the minus earth of capacitor C 6, the output of amplifier NE5532 (1) is connected with its another in-phase input end (5), its another inverting input (6) is connected with output (7), output (7) connects the positive pole of capacitor C 7, and the negative pole of capacitor C 7 is output OUT.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
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| CN 02159452 CN1263345C (en) | 2002-12-31 | 2002-12-31 | Underground sound sensitive sensor |
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| CN 02159452 CN1263345C (en) | 2002-12-31 | 2002-12-31 | Underground sound sensitive sensor |
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| CN1263345C true CN1263345C (en) | 2006-07-05 |
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| CN109708744B (en) * | 2019-03-07 | 2024-05-24 | 北京世纪之星应用技术研究中心 | Double-vibrator solid sound sensor device |
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2002
- 2002-12-31 CN CN 02159452 patent/CN1263345C/en not_active Expired - Lifetime
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| US7949231B2 (en) | 2002-06-24 | 2011-05-24 | Lg Electronics Inc. | Recording medium having data structure for managing reproduction of multiple reproduction path video data recorded thereon and recording and reproducing methods and apparatuses |
| US7783159B2 (en) | 2002-06-24 | 2010-08-24 | Lg Electronics Inc. | Recording medium having data structure for managing reproduction of multiple reproduction path video data for at least a segment of a title recorded thereon and recording and reproducing methods and apparatuses |
| US7672567B2 (en) | 2002-06-24 | 2010-03-02 | Lg Electronics Inc. | Recording medium having data structure for managing reproduction of multiple reproduction path video data for at least a segment of a title recorded thereon and recording and reproducing methods and apparatuses |
| US7809243B2 (en) | 2002-06-24 | 2010-10-05 | Lg Electronics, Inc. | Recording medium having data structure including navigation control information for managing reproduction of video data recorded thereon and recording and reproducing methods and apparatuses |
| US7813237B2 (en) | 2002-10-14 | 2010-10-12 | Lg Electronics Inc. | Recording medium having data structure for managing reproduction of multiple audio streams recorded thereon and recording and reproducing methods and apparatuses |
| US7961570B2 (en) | 2002-10-14 | 2011-06-14 | Lg Electronics Inc. | Recording medium having data structure for managing reproduction of multiple audio streams recorded thereon and recording and reproducing methods and apparatuses |
| US7840121B2 (en) | 2002-10-15 | 2010-11-23 | Lg Electronics Inc. | Recording medium having data structure for managing reproduction of multiple graphics streams recorded thereon and recording and reproducing methods and apparatuses |
| US7769272B2 (en) | 2002-11-20 | 2010-08-03 | Lg Electronics Inc. | Recording medium having data structure for managing reproduction of at least video data recorded thereon and recording and reproducing methods and apparatuses |
| US8831406B2 (en) | 2002-11-20 | 2014-09-09 | Lg Electronics Inc. | Recording medium having data structure for managing reproduction of at least video data recorded thereon and recording and reproducing methods and apparatuses |
| US8886021B2 (en) | 2002-11-20 | 2014-11-11 | Lg Electronics Inc. | Recording medium having data structure for managing reproduction of at least video data recorded thereon and recording and reproducing methods and apparatuses |
| US7693394B2 (en) | 2003-02-26 | 2010-04-06 | Lg Electronics Inc. | Recording medium having data structure for managing reproduction of data streams recorded thereon and recording and reproducing methods and apparatuses |
| US7809775B2 (en) | 2003-02-27 | 2010-10-05 | Lg Electronics, Inc. | Recording medium having data structure for managing playback control recorded thereon and recording and reproducing methods and apparatuses |
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| CN1512819A (en) | 2004-07-14 |
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