CN202711680U - Electronic loudspeaker for motorized vehicles and vessels - Google Patents
Electronic loudspeaker for motorized vehicles and vessels Download PDFInfo
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- CN202711680U CN202711680U CN 201220378412 CN201220378412U CN202711680U CN 202711680 U CN202711680 U CN 202711680U CN 201220378412 CN201220378412 CN 201220378412 CN 201220378412 U CN201220378412 U CN 201220378412U CN 202711680 U CN202711680 U CN 202711680U
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Abstract
The utility model relates to an electronic loudspeaker for motorized vehicles and vessels. The electronic loudspeaker for the motorized vehicles and vessels comprises a voltage booster circuit, a piezoelectric sensing unit, a feedback circuit and a loudspeaker unit. One end of an input terminal of the voltage booster circuit is connected with an input power supply, the other end of the input terminal of the voltage booster circuit is connected to the feedback circuit, and an output terminal of the voltage booster circuit is connected with the piezoelectric sensing unit. The piezoelectric sensing unit is respectively connected with the feedback circuit and the loudspeaker unit. The voltage booster circuit carries out boost processing on an input voltage, generates a boosted drive voltage and transmits the boosted drive voltage to the piezoelectric sensing unit. The piezoelectric sensing unit uses the received drive voltage to drive a vibration film of the loudspeaker unit to vibrate and generate sound, and generates a sensing voltage. The feedback circuit establishes oscillation make and break based on the sensing voltage, and controls the working state of the voltage booster circuit. The electronic loudspeaker for the motorized vehicles and vessels has high electro-acoustic conversion efficiency, improves the energy utilization rate, and is in favor of energy saving and environmental protection.
Description
Technical field
The utility model relates to a kind of electroacoustic device, relates in particular to a kind of motorized vehicles and vessels electronic horn.
Background technology
Loudspeaker are can convert the electrical signal to acoustical signal and propagate into airborne electroacoustics transducer.Since automobile in 1886 was born, car horn had become one of the parts that must install on the automobile.In the driving process of automobile, the driver sends essential acoustic signal with regulation as required, and warning pedestrian and cause that other vehicles note is to guarantee traffic safety.
Along with the development of automotive engineering, a lot of parts are all towards the future development of electronization on the automobile, and car horn has also carried out multiple improvement, experienced the progress generation upon generation of such as manual, pneumatic, electronic, electronics.Except pneumatic loudspeaker, no matter be the motor machine loudspeaker that the contact is arranged, or contactless electronic horn, the principle of sound of the car horn of these power consumption controls does not all break away from the principle of sound of electromagnetic type, constantly vibrate by solenoid actuated one moving (or being called armature) unshakable in one's determination band dynamic diaphragm, thereby promote air sounding or bump sounding.Yet the common electroacoustic of the sonification system of this electromagnetic type conversion usefulness is not high, causes capacity usage ratio low, is unfavorable for energy-conserving and environment-protective, and electromagnetic type loudspeaker complex structure often, also produces easily electromagnetic interference (EMI).
The utility model content
The purpose of this utility model provides a kind of motorized vehicles and vessels electronic horn, and its electro-acoustic conversion efficiency is high, improves energy utilization rate, is conducive to energy-conserving and environment-protective, meets simultaneously technical standard and the request for utilization of motorized vehicles and vessels, applicable to all kinds of motorized vehicles and vessels.
For achieving the above object, the utility model provides a kind of motorized vehicles and vessels electronic horn, and described motorized vehicles and vessels comprises with electronic horn: booster circuit, piezoelectricity sensing unit, feedback circuit and loudspeaker unit;
One end of the input end of described booster circuit is connected with input power, the other end of input end is connected to described feedback circuit, the output terminal of described booster circuit is connected with described piezoelectricity sensing unit, and described piezoelectricity sensing unit is connected with described feedback circuit and described loudspeaker unit respectively;
Described booster circuit is to voltage processings of boosting of input, and the driving voltage after generation is boosted also is transmitted to described piezoelectricity sensing unit; The described driving voltage that described piezoelectricity sensing unit will receive drives the vibrating diaphragm vibration sounding of described loudspeaker unit, and generation has the induced voltage of oscillation frequency and sends to described feedback circuit; Described feedback circuit is set up the vibration break-make according to described induced voltage, controls the duty of described booster circuit.
Further, described booster circuit comprises step-up transformer;
One end of the primary coil of described step-up transformer is connected with described input voltage, and the other end of described primary coil is connected to the output of described feedback circuit, and the duty of described booster circuit is controlled by described feedback circuit; The secondary coil of described step-up transformer exports described piezoelectricity sensing unit to.
Further, described motorized vehicles and vessels also comprises with electronic horn:
Resonant circuit is connected in parallel with described piezoelectricity sensing unit, and the oscillation frequency of the resonance frequency of described resonant circuit and described piezoelectricity sensing unit is suitable.
Further, described piezoelectricity sensing unit comprises three utmost point auto-excitation type piezoelectric patches, and described piezoelectric patches is connected with the vibrating diaphragm of described loudspeaker unit.
Further, described piezoelectricity sensing unit and loudspeaker unit are specially the piezoelectric loudspeaker of Integral design, and described piezoelectric loudspeaker comprises piezoelectric patches, vibrating diaphragm and acoustic resonance cavity, and described piezoelectric patches is produced on described vibrating diaphragm.
Further, described acoustic resonance cavity is specially snail resonator cavity or horn type resonator cavity.
Further, described feedback circuit comprises partial pressure unit and power amplification unit, described partial pressure unit is connected with described piezoelectricity sensing unit, described power amplification unit is connected with an end of described booster circuit, passes to described power amplification unit after the induced voltage process partial pressure unit dividing potential drop that described feedback circuit receives.
Further, described power amplification unit comprises transistor or field effect transistor.
Further, described motorized vehicles and vessels also comprises with electronic horn:
Overvoltage crowbar is connected in the two ends of described power amplification unit.
The motorized vehicles and vessels electronic horn that the utility model provides, adopt the vocal skill of piezoelectric patches, electro-acoustic conversion efficiency is high, is conducive to energy-conserving and environment-protective, the electronic horn that utilizes piezoelectric patches to design is simple in structure, be not subject to electromagnetic interference (EMI), by the driving voltage of booster circuit raising piezoelectric patches, simultaneously, adopt acoustic resonance cavity that sound is focused on amplification, can meet the motorized vehicles and vessels technical standard, reach the requirement that motorized vehicles and vessels uses, be applicable to all kinds of motorized vehicles and vessels.
Description of drawings
The motorized vehicles and vessels that Fig. 1 provides for the utility model embodiment one theory diagram of electronic horn;
The motorized vehicles and vessels that Fig. 2 provides for the utility model embodiment two circuit theory diagrams of electronic horn.
Embodiment
Below by drawings and Examples, the technical solution of the utility model is described in further detail.
Embodiment one
Fig. 1 is the motorized vehicles and vessels that provides of present embodiment with the theory diagram of electronic horn, and as shown in Figure 1, the motorized vehicles and vessels of present embodiment comprises drive unit 1 and loudspeaker unit 2 with electronic horn.
Wherein, drive unit 1 comprises booster circuit 11, piezoelectricity sensing unit 12, feedback circuit 13.
When the piezoelectric patches of giving piezoelectricity sensing unit 12 applies excitation electrical field, inverse piezoelectric effect according to piezoelectric crystal, piezoelectric patches can produce deformation, and the vibrating diaphragm of piezoelectric patches and loudspeaker unit links together, when piezoelectric patches stretched or shrink, the vibrating membrane sector-meeting was correspondingly crooked up or down, and the to-and-fro movement by piezoelectric patches drives vibrating diaphragm and constantly vibrates, thereby the promotion air sends sound equipment.This inverse piezoelectric effect of utilizing piezoelectric and the acoustical generators such as loudspeaker of sounding work, usually have simple in structure, stable and reliable for performance, conversion efficiency is high and advantage low in energy consumption etc.
Loudspeaker unit 2 is used for being subject under the described driving voltage driving, with piezoelectricity sensing unit 12 vibration soundings at piezoelectricity sensing unit 12.The piezoelectricity sensing unit 12 of the vibrating diaphragm of loudspeaker unit 2 and drive unit 1 links together.Drive unit 1 is loaded on the piezoelectricity sensing unit 12 by the booster circuit 11 rear generation driving voltage that boosts, piezoelectricity sensing unit 12 is according to inverse piezoelectric effect, deformation vibration when being arranged, voltage-drop loading occurs, the displacement of deformation is directly proportional with the amplitude of the voltage signal of loading, and piezoelectricity sensing unit 12 is exported by induction end owing to deformation meeting generation induced voltage has occured simultaneously.Because the reciprocal deformation of piezoelectric patches, can produce the induced voltage with oscillation frequency, like this when work, feedback circuit 13 is pressed the oscillation frequency break-make under the control of described induced voltage, that is, so that power amplification unit 132 vibration conductings, in order to control the duty of booster circuit 11, booster circuit 11 driving voltage that rear generation has oscillation frequency that boosts, the double vibrations that drives piezoelectricity sensing unit 12 drives the vibrating diaphragm sounding of loudspeaker unit 2.
It is worth mentioning that described piezoelectricity sensing unit and loudspeaker unit preferably adopt the mode of Integral design, namely adopt piezoelectric loudspeaker.Adopt the motorized vehicles and vessels of piezoelectric loudspeaker to be elaborated with electronic horn below by two couples of embodiment.
Embodiment two
Fig. 2 is the motorized vehicles and vessels that provides of present embodiment with the circuit theory diagrams of electronic horn; as shown in Figure 2, the motorized vehicles and vessels that provides of present embodiment comprises booster circuit 21, piezoelectric loudspeaker 22, feedback circuit 23, polar protective circuit 24, filtering circuit 25, mu balanced circuit 26, resonant circuit 27 and overvoltage crowbar 28 with electronic horn.
Booster circuit 21 produces the driving voltage after boosting after processing for the voltage of inputting is boosted.Booster circuit 21 comprises step-up transformer L1, one end of the primary coil of step-up transformer L1 is connected with input voltage, the other end of the primary coil of step-up transformer L1 is connected to the output of feedback circuit, and the duty of booster circuit is fed circuit control thus; The secondary coil of step-up transformer L1 exports the two poles of the earth of the piezoelectric patches JT of piezoelectric loudspeaker to.Step-up transformer L1 can adopt the self coupling step-up transformer, perhaps, also can adopt the transformer of other types.As shown in FIG., the output of feedback circuit is connected with the negative pole end of the primary and secondary coil of step-up transformer L1, those of ordinary skill in the art is to be understood that, the output of feedback circuit also can adopt similar mode to be connected with the negative pole end of primary and secondary coil, by the on off operating mode of feedback circuit, the duty of control booster circuit.
Piezoelectric loudspeaker 22 is used for receiving described driving voltage that booster circuit 21 produces and drives and carry out vibration sounding, and produces the induced voltage with oscillation frequency and export feedback circuit 23 to.Piezoelectric loudspeaker 22 comprises piezoelectric patches JT, vibrating diaphragm and acoustic resonance cavity, and piezoelectric patches JT is produced on vibrating diaphragm, and described acoustic resonance cavity focuses on amplification to the sound that piezoelectric patches JT and vibrating diaphragm send.Piezoelectric patches JT adopts three utmost point auto-excitation type piezoelectric patches, and the positive and negative polarities of piezoelectric patches JT are connected with the secondary coil of step-up transformer L1, and the induction end of piezoelectric patches JT is connected to feedback circuit.Described acoustic resonance cavity can adopt snail resonator cavity or horn type resonator cavity, can gather sound to vibration sounding, reaches the effect of concentrating sounding, to meet the motorized vehicles and vessels technical standard, satisfies the request for utilization of motorized vehicles and vessels.
Feedback circuit 23 is used for receiving described induced voltage, and sets up the vibration break-make according to described induced voltage, the duty of control booster circuit 21.Feedback circuit 23 specifically comprises partial pressure unit 231 and power amplification unit 232.Partial pressure unit 231 comprises divider resistance R1 and divider resistance R2, receives the induced voltage that produces from the induction end of piezoelectric patches JT, will be connected to power amplification unit after the described induced voltage dividing potential drop.
Power amplification unit 232 is specially field effect transistor T1, can certainly adopt transistor, be added in the grid of field effect transistor T1 through the induced voltage after the partial pressure unit dividing potential drop, the source ground of field effect transistor T1, an end of the primary coil of step-up transformer L1 is received in the drain electrode of field effect transistor T1, owing to be subject to the effect of induced voltage, so that field effect transistor T1 is in the state of vibration break-make, thereby the duty of control booster circuit 21, so that input power is through after booster circuit 21 boosts, produce the driving voltage of vibration, drive piezoelectric patches JT vibration, make piezoelectric loudspeaker 22 sounding.
Polar protective circuit 24 comprises diode D1, and diode D1 forward is connected in series in input power VCC, can prevent that reverse power connection to the damage of circuit, avoiding loudspeaker to burn out.
Filtering circuit 25 comprises filter capacitor C3, and filter capacitor C3 is connected in parallel in input power VCC, is connected in after the diode D1, in order to reduce the noise signal of power supply.
Mu balanced circuit 26 comprises current-limiting resistance R4 and voltage stabilizing diode DW1, and current-limiting resistance R4 and voltage stabilizing diode DW1 are connected in series, and current-limiting resistance R4 is connected in through the input power VCC after the diode D1.Be connected to the grid of field effect transistor T1 behind the voltage of voltage regulation process divider resistance R3 that voltage stabilizing diode DW1 provides in the mu balanced circuit, for field effect transistor T1 provides a grid bias.
Resonant circuit 27 comprises resonant capacitance C1, resonant capacitance C1 and piezoelectricity sensing unit are connected in parallel, also be connected in parallel in simultaneously the two ends of step-up transformer L1 secondary coil, the oscillation frequency of the resonance frequency of resonant circuit 27 and described piezoelectricity sensing unit is suitable, realizes better resonance effect.
Overvoltage crowbar 28 is used for forward and reverse superpotential that absorbing circuit produces under large current excitation, protection power amplification unit 232.Overvoltage crowbar 28 comprises diode D2 and capacitor C 2; diode D2 and capacitor C 2 are connected in parallel in respectively the two ends of power amplification unit; diode D2 oppositely is connected between the source electrode and drain electrode of field effect transistor T1; diode D2 is used for absorbing inverse overvoltage, and capacitor C 2 is used for absorbing the forward superpotential.Wherein, capacitor C 2 also is used for the vibration of start-up circuit, and in the moment that initially powers on, electric current passes through through the primary coil of step-up transformer L1 and 2 moments of capacitor C, and the piezoelectric patches JT that step-up transformer L1 secondary coil output voltage drives piezoelectric loudspeaker starts working.
The motorized vehicles and vessels electronic horn that the utility model provides is a self-oscillatory piezoelectric sound producing system, comprises that booster circuit 21, piezoelectric loudspeaker 22, feedback circuit 23 consist of the piezoelectric patches self-maintained circuit.Before setting up self-sustained oscillation, the anti-error-polarity connection circuit access of power supply through being consisted of by diode D1, through after comprising the mu balanced circuit of current-limiting resistance R4 and voltage stabilizing diode DW1, provide a grid bias (quiescent operation voltage) through divider resistance R3 for field effect transistor T1, but this moment, field effect transistor T1 still was in cut-off state.
It sets up self-oscillatory principle of work: when initially powering on, electric current passes through through the primary coil of step-up transformer L1 and 2 moments of capacitor C, step-up transformer L1 secondary coil is sensed the curent change of primary coil, produce voltage, secondary coil through step-up transformer L1 is added on the two ends of piezoelectric patches JT, piezoelectric patches JT is because inverse piezoelectric effect produces deformation, induction end at piezoelectric patches JT has an induced voltage generation, after divider resistance R1 and divider resistance R2 dividing potential drop, be connected on the grid of field effect transistor T1, field effect transistor T1 starts working, be in conducting state, step-up transformer L1 primary coil is responded to the rear drive piezoelectric patches JT vibration sounding that boosts by electric current through step-up transformer L1 secondary coil.Reciprocal variation along with piezoelectric patches JT deformation, piezoelectric patches JT produces the induced voltage that vibrates is loaded on field effect transistor T1 after dividing potential drop grid, so that field effect transistor T1 sets up the vibration break-make, namely, so that the negative pole of the primary coil of step-up transformer L1 is set up the vibration conducting over the ground, thereby the duty of control step-up transformer L1 forms self-sustained oscillation.Like this, just can produce and the consistent pronouncing frequency of the whole acoustic feature of loudspeaker owing to piezoelectric patches JT to-and-fro movement.
For piezoelectric loudspeaker, the vibrating diaphragm of piezoelectric patches and loudspeaker is one, so the whole natural resonance point of the vibrating diaphragm of piezoelectric patches and loudspeaker determines when making piezoelectric patches.Although since the sound cavities of every loudspeaker in the mill fine difference cause every loudspeaker different, but because piezoelectric patches is self-sustained oscillation, piezoelectric patches can be regulated automatically within the specific limits, after forming self-sustained oscillation, come the oscillation frequency of Circuit tuning by the reciprocating frequency of piezoelectric patches, so that the resonance frequency of the oscillation frequency of circuit and horn membrane is suitable, keep high electro-acoustic conversion efficiency.
The motorized vehicles and vessels electronic horn that the utility model provides adopts piezoelectric patches pronunciation principle to drive the electronic horn pronunciation, and its electro-acoustic conversion efficiency is high, has the advantage of energy-conserving and environment-protective, is the environmental type motorized vehicles and vessels electronic horn of a new generation.Provide higher driving voltage by booster circuit for piezoelectric patches, satisfy the requirement of piezoelectric loudspeaker driving voltage, adopt simultaneously acoustic resonance cavity that sound is focused on amplification, meet the requirement motorized vehicles and vessels technical standard, that satisfy the motorized vehicles and vessels use so that electronic horn can reach.
Above-described embodiment; the purpose of this utility model, technical scheme and beneficial effect are further described; institute is understood that; the above only is embodiment of the present utility model; and be not used in and limit protection domain of the present utility model; all within spirit of the present utility model and principle, any modification of making, be equal to replacement, improvement etc., all should be included within the protection domain of the present utility model.
Claims (9)
1. a motorized vehicles and vessels electronic horn is characterized in that, described motorized vehicles and vessels comprises with electronic horn: booster circuit, piezoelectricity sensing unit, feedback circuit and loudspeaker unit;
One end of the input end of described booster circuit is connected with input power, the other end of input end is connected to described feedback circuit, the output terminal of described booster circuit is connected with described piezoelectricity sensing unit, and described piezoelectricity sensing unit is connected with described feedback circuit and described loudspeaker unit respectively;
Described booster circuit is to voltage processings of boosting of input, and the driving voltage after generation is boosted also is transmitted to described piezoelectricity sensing unit; The described driving voltage that described piezoelectricity sensing unit will receive drives the vibrating diaphragm vibration sounding of described loudspeaker unit, and generation has the induced voltage of oscillation frequency and sends to described feedback circuit; Described feedback circuit is set up the vibration break-make according to described induced voltage, controls the duty of described booster circuit.
2. motorized vehicles and vessels electronic horn according to claim 1 is characterized in that, described booster circuit comprises step-up transformer;
One end of the primary coil of described step-up transformer is connected with described input voltage, and the other end of described primary coil is connected to the output of described feedback circuit, and the duty of described booster circuit is controlled by described feedback circuit; The secondary coil of described step-up transformer exports described piezoelectricity sensing unit to.
3. motorized vehicles and vessels electronic horn according to claim 1 is characterized in that, described motorized vehicles and vessels also comprises with electronic horn:
Resonant circuit is connected in parallel with described piezoelectricity sensing unit, and the oscillation frequency of the resonance frequency of described resonant circuit and described piezoelectricity sensing unit is suitable.
4. motorized vehicles and vessels electronic horn according to claim 1 is characterized in that, described piezoelectricity sensing unit comprises three utmost point auto-excitation type piezoelectric patches, and described piezoelectric patches is connected with the vibrating diaphragm of described loudspeaker unit.
5. motorized vehicles and vessels electronic horn according to claim 1, it is characterized in that, described piezoelectricity sensing unit and loudspeaker unit are specially the piezoelectric loudspeaker of Integral design, described piezoelectric loudspeaker comprises piezoelectric patches, vibrating diaphragm and acoustic resonance cavity, and described piezoelectric patches is produced on described vibrating diaphragm.
6. motorized vehicles and vessels electronic horn according to claim 5 is characterized in that, described acoustic resonance cavity is specially snail resonator cavity or horn type resonator cavity.
7. motorized vehicles and vessels electronic horn according to claim 1, it is characterized in that, described feedback circuit comprises partial pressure unit and power amplification unit, described partial pressure unit is connected with described piezoelectricity sensing unit, described power amplification unit is connected with an end of described booster circuit, passes to described power amplification unit after the induced voltage process partial pressure unit dividing potential drop that described feedback circuit receives.
8. motorized vehicles and vessels electronic horn according to claim 7 is characterized in that, described power amplification unit comprises transistor or field effect transistor.
9. motorized vehicles and vessels electronic horn according to claim 7 is characterized in that, described motorized vehicles and vessels also comprises with electronic horn:
Overvoltage crowbar is connected in the two ends of described power amplification unit.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201220378412 CN202711680U (en) | 2012-08-01 | 2012-08-01 | Electronic loudspeaker for motorized vehicles and vessels |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201220378412 CN202711680U (en) | 2012-08-01 | 2012-08-01 | Electronic loudspeaker for motorized vehicles and vessels |
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| Publication Number | Publication Date |
|---|---|
| CN202711680U true CN202711680U (en) | 2013-01-30 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 201220378412 Expired - Lifetime CN202711680U (en) | 2012-08-01 | 2012-08-01 | Electronic loudspeaker for motorized vehicles and vessels |
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| CN (1) | CN202711680U (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103578459A (en) * | 2012-08-01 | 2014-02-12 | 万喻 | Electronic horn for motor vehicle or motor boat |
| CN109379661A (en) * | 2018-11-29 | 2019-02-22 | 东莞泉声电子有限公司 | Safety-type high-fidelity static earphone |
-
2012
- 2012-08-01 CN CN 201220378412 patent/CN202711680U/en not_active Expired - Lifetime
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103578459A (en) * | 2012-08-01 | 2014-02-12 | 万喻 | Electronic horn for motor vehicle or motor boat |
| CN103578459B (en) * | 2012-08-01 | 2016-05-25 | 万喻 | Motorized vehicles and vessels electronic horn |
| CN109379661A (en) * | 2018-11-29 | 2019-02-22 | 东莞泉声电子有限公司 | Safety-type high-fidelity static earphone |
| CN109379661B (en) * | 2018-11-29 | 2024-01-09 | 东莞泉声电子有限公司 | Safety high-fidelity electrostatic earphone |
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| CX01 | Expiry of patent term |
Granted publication date: 20130130 |
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| CX01 | Expiry of patent term |