CN104661170A - Fault detection system for multiple speakers - Google Patents
Fault detection system for multiple speakers Download PDFInfo
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- CN104661170A CN104661170A CN201510101743.2A CN201510101743A CN104661170A CN 104661170 A CN104661170 A CN 104661170A CN 201510101743 A CN201510101743 A CN 201510101743A CN 104661170 A CN104661170 A CN 104661170A
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Abstract
The invention discloses a fault detection system for multiple speakers. The fault detection system for multiple speakers is characterized by comprising a differential amplification circuit, a second-stage operational circuit, a voltage comparator and a fault alarm circuit, wherein two signal terminals of the differential amplification circuit are connected in series in an audio loop of a multi-speaker system, after a rectifying and filtering circuit rectifies and filters signals output by the second-stage operational circuit, the signals are input to an in-phase input end of the voltage comparator, and an anti-phase input end of the voltage comparator is connected to a power source through a potentiometer; the fault alarm circuit does not give an alarm by adjusting the potentiometer at the anti-phase input end of the voltage comparator; when one speaker is broken down and disconnected, differential signals input into the differential amplification circuit are reduced, and output level of the voltage comparator is overturned to trigger alarm. The system has simple circuits and low cost and is convenient to mount, all that is required is to connect the system into the speakers in series, and the operation can be performed; the system can be mounted to a master control room, can also be mounted on each speaker, and can detect whether speaker damage exists in real time.
Description
Technical field
The present invention relates to a kind of multitone case fault detection system, in particular, particularly relate to a kind of certain or some multitone case fault detection system of disconnecting or breaking down of can detecting in real time in numerous audio amplifier.
Background technology
Supermarket, the public places such as sight spot often use wired broadcasting to carry out notifying or publicizing, this type of application is general adopts multiple wired audio amplifier to broadcast on a large scale, audio amplifier quantity has several to tens, the large-scale sight spot audio amplifier quantity had even exceedes up to a hundred, be distributed in hundreds of square metre even thousands of square metres of regions, be difficult to discover if certain audio amplifier breaks down, if the place of inner more noisy and intensive installation audio amplifier in supermarket, because audio amplifier relative distance is nearer, if certain audio amplifier damages, the personnel of needing repairing press close to aerial audio amplifier could find fault, inconvenience is brought to maintenance work.For this reason, those skilled in the art develops multitone case fault detection system, by this device can to real-time detect in numerous audio amplifier certain or some there is fault, alarm signal can be sent to broadcast management centre, also this device quick position fault audio amplifier can be passed through, thus notify that engineering staff rushes to repair in time, ensure that the broadcast of public place can normally run.
Summary of the invention
The present invention, in order to overcome the shortcoming of above-mentioned technical problem, provides a kind of certain or some multitone case fault detection system of disconnecting or breaking down of can detecting in real time in numerous audio amplifier.
Multitone case fault detection system of the present invention, its special feature is: comprise differential amplifier circuit, second level discharge circuit, voltage comparator and failure alarm circuit, two signal ends of differential amplifier circuit are series in the audio loop of multitone case, and differential amplifier circuit inputs to the input of second level discharge circuit after being amplified by differential signal; The output of second level discharge circuit is provided with current rectifying and wave filtering circuit, after the signal rectification that current rectifying and wave filtering circuit exports second level discharge circuit, filtering, input to the in-phase input end of voltage comparator, the inverting input of voltage comparator is connected on power supply through potentiometer; Failure alarm circuit is connected on the output of voltage comparator;
During use, the signal end of differential amplifier circuit is series at after in audio loop, makes the voltage of voltage comparator inverting input be greater than the voltage of in-phase input end by the resistance of regulator potentiometer, make failure alarm circuit send alarm signal; Then by changing the resistance of potentiometer until failure alarm circuit is not reported to the police just;
When audio loop generation open circuit or when having audio amplifier to disconnect, differential signal to be amplified can be made to reduce, the voltage inputing to voltage comparator in-phase input end also diminishes thereupon, the voltage of in-phase input end is made to be less than the voltage of inverting input, the output state of voltage comparator changes, failure alarm circuit sends alarm signal, has audio amplifier to produce fault to point out staff.
Multitone case fault detection system of the present invention, described differential amplifier circuit, second level discharge circuit and voltage comparator are made up of the first operational amplifier, the second operational amplifier and the 3rd operational amplifier respectively;
The homophase of the first operational amplifier is connected with R2 through resistance R3, R1 successively with inverting input, be in series with resistance R4 between inverting input and output, the output signal of the first operational amplifier is connected to the in-phase input end of the second operational amplifier after the filter circuit that electric capacity C1 and resistance R6 forms;
The inverting input of the second operational amplifier is connected on positive source through resistance R5, output is connected to the in-phase input end of the 3rd operational amplifier successively through diode D4 and resistance R8, the inverting input of the second operational amplifier is connected to the junction of diode D4 and resistance R8 through resistance R7; The in-phase input end of the 3rd operational amplifier is connected to power supply on the ground through electric capacity C2 and resistance R9;
The anti-phase input of the 3rd operational amplifier is terminated on the armature contact of potentiometer, and potentiometer is being connected to power supply just and between power supply ground, output is connected with failure alarm circuit after connecting with resistance R10.
Multitone case fault detection system of the present invention, described failure alarm circuit is made up of light-emitting diode D2 and buzzer, the positive pole of diode D2 is connected to power supply on the ground, negative pole is connected with the output of the 3rd operational amplifier through resistance R11, and buzzer is connected to the output of the 3rd operational amplifier after connecting with resistance R12 and diode D3.
Multitone case fault detection system of the present invention, also comprises the normal condition indicator light be made up of light-emitting diode D1, and the positive pole of light-emitting diode D1, negative pole are connected on the negative pole of light-emitting diode D2, positive pole respectively.
Multitone case fault detection system of the present invention, the resistance of described resistance R1 is 0.2 ~ 1.0 Ω.
Multitone case fault detection system of the present invention, described first operational amplifier, the second operational amplifier and the 3rd operational amplifier are made up of 3 discharge circuits in amplifier chip LM348N.
The invention has the beneficial effects as follows: multitone case fault detection system of the present invention, by the resistance R1 of differential amplifier circuit input is series in the audio loop of multitone case, the output signal of differential amplifier circuit is successively after the process of the amplification of second level discharge circuit, current rectifying and wave filtering circuit, input to the positive input of voltage comparator, by the potentiometer on regulation voltage comparator inverting input, failure alarm circuit is not reported to the police just; When there being audio amplifier to break down during open circuit, the differential signal inputed in differential amplifier circuit can be made to reduce, and the output level obtaining voltage comparator occurs to overturn and trigger alarm, solve the problem that in existing many sound box systems, fault is not easily found, beneficial effect is remarkable.
Native system circuit is simple, with low cost, easy for installation, only needs this device series connection access audio amplifier to get final product work.Master control room can be installed to, also can be installed on each audio amplifier, if be installed to master control room, can detect in real time and whether have audio amplifier to damage, if be installed on certain audio amplifier, this audio amplifier can be detected in real time and whether damage, therefore master control room and each audio amplifier can be combined installation, fault is found, by this device localizing faults on single audio amplifier by master control room.
Accompanying drawing explanation
Fig. 1 is the schematic diagram of multitone case fault detection system of the present invention;
Fig. 2 is the circuit diagram of multitone case fault detection system of the present invention.
In figure: 1 differential amplifier circuit, 2 second level discharge circuits, 3 current rectifying and wave filtering circuits, 4 voltage comparators, 5 potentiometers, 6 power supplys, 7 normal condition indicator lights, 8 failure alarm circuits, 9 first operational amplifiers, 10 second operational amplifiers, 11 the 3rd operational amplifiers.
Embodiment
Below in conjunction with accompanying drawing and embodiment, the invention will be further described.
As shown in Figure 1, give the schematic diagram of multitone case fault detection system of the present invention, it comprises differential amplifier circuit 1, second level discharge circuit 2, current rectifying and wave filtering circuit 3, voltage comparator 4, potentiometer 5, normal condition indicator light 7, failure alarm circuit 8; Two signal ends that the IN end of shown differential amplifier circuit 1 and OUT end are differential amplifier circuit 1, two signal ends of differential amplifier circuit 1 are series in the audio loop of multitone case, carry out amplification process the differential signal obtained.Differential amplifier circuit 1 inputs in second level discharge circuit 2 after being amplified by differential signal again and amplifies further.Further amplifying signal inputs in current rectifying and wave filtering circuit 3 by second level discharge circuit 2.
After the signal of current rectifying and wave filtering circuit 3 to input carries out rectification and filtering, be converted into the in-phase input end that direct current signal inputs to voltage comparator 4.Potentiometer 5 is connected with power supply 6 by the inverting input of voltage comparator 4, and failure alarm circuit 8, normal condition indicator light 7 are all connected to the output of voltage comparator 4, the warning under carrying out malfunction respectively and under normal condition.
During use, by the resistance in regulator potentiometer 5 place in circuit, make failure alarm circuit be in alarm condition, now the voltage of voltage comparator in-phase input end is less than the voltage of inverting input, voltage comparator output low level.Then the resistance in potentiometer 5 place in circuit is reduced gradually, when fault alarm 8 stop alarm, the change of stopping potential device 5 resistance immediately, now the voltage of voltage comparator 4 in-phase input end is just greater than the voltage of inverting input, voltage comparator 5 exports high level, fault alarm 8 stop alarm, and normal condition indicator light 7 is lighted.
When there being audio amplifier open circuit in multitone case loop, differential signal to be amplified can be made to reduce, and make the voltage of voltage comparator in-phase input end be less than the voltage of inverting input, the output state of voltage comparator changes, output low level, failure alarm circuit sends alarm signal.
As shown in Figure 2, give the circuit diagram of multitone case fault detection system of the present invention, shown differential amplifier circuit 1, second level discharge circuit 2, voltage comparator 4 are made up of the first operational amplifier 9, second operational amplifier 10 and the 3rd operational amplifier 11 respectively, current rectifying and wave filtering circuit 3 diode D4 and electric capacity C2 forms, normal condition indicator light 7 is made up of light-emitting diode D1, and failure alarm circuit 8 is made up of light-emitting diode D2 and buzzer Buzzer.
The in-phase input end of the first operational amplifier is connected with one end of resistance R1 through resistance R3, inverting input is connected with the other end of resistance R1 through resistance R2, during use, the two ends of resistance R1 are series in audio signal loop, the electric current of audio signal will produce differential signal by resistance R1, inputs to homophase, the inverting input of the first operational amplifier 9.The output of the first operational amplifier 9 is connected through resistance R4 with its inverting input, and output is connected to the in-phase input end of the second operational amplifier 10 after electric capacity C1, so that the alternating component of the second operational amplifier 10 pairs of differential signals is amplified.The in-phase input end of the second operational amplifier 10 is connected through resistance R6 and power supply, and resistance R5 is just connected with power supply by direction input.The resistance of resistance R1 is chosen between 0.2 ~ 1.0 Ω, is preferably 0.5 Ω.
The output of the second operational amplification circuit 10 is connected with the positive pole of diode D4, and the negative pole of diode D4 is connected with the in-phase input end of the 3rd operational amplifier 11 through resistance R8, and diode D4 realizes the rectified action to output signal.The in-phase input end of the 3rd operational amplifier 11 is also connected through resistance R9 and electric capacity C2 and power supply, and electric capacity C2 realizes the filter action to rectified signal, makes it be converted into the level and smooth direct current signal of waveform, inputs to the in-phase input end of voltage comparator 4.The inverting input of the second operational amplifier 9 is connected to the junction of D4 and R8 through resistance R7.
Potentiometer 5 is connected to power supply just and between power supply ground after connecting with resistance R10, the anti-phase input of the 3rd operational amplifier 11 is terminated on the armature contact of potentiometer 5, access the resistance size between the inverting input of the 3rd operational amplifier and power supply ground by change potentiometer 5, the voltage swing of inverting input can be changed.The positive pole of light-emitting diode D2 is connected with power supply ground, and negative pole is connected with the output of the 3rd operational amplifier 11 through resistance R11, and light-emitting diode D1 is together with D2 reverse parallel connection; Buzzer Buzzer is connected on the output of the 3rd operational amplifier 11 through resistance R12 and diode D3.When the 3rd operational amplifier 11 exports high level (+15V), only diode D1 is lit, and represents the work of multitone case all normal; As output low level (-15V), light-emitting diode D2 is lit, buzzer work, reminds relevant staff to have audio amplifier to there is fault by sound and light alarm signal.
The IN section of differential amplifier circuit 1 and the series connection of OUT end are accessed the audio loop of audio amplifier, ensure that audio amplifier is all intact, resistance between 1,3 ends of increase potentiometer WS-1, when resistance between 1,3 ends increases to certain value, buzzer just can sounding, when now slightly reducing the resistance between 1,3 ends, buzzer just can stop sounding, the current location of potentiometer WS-1 is this device criticality alarm point, if now audio amplifier disconnects, buzzer just can sounding alarm, D2 indicator light is lighted, and indicates this audio amplifier to occur open circuit fault.If master control room adds this device, only need by this device series connection access audio amplifier basic routing line, method of adjustment is similar above-mentioned, if there is certain or some audio amplifier open circuit faults in whole system, just can report to the police.
This principle of device is as follows: after differential amplifier circuit 1 being accessed the audio loop of audio amplifier, if there is no audio amplifier short circuit, R1 just has electric current to be passed through, after amplifier chip LM348N two-stage is amplified, again through rectification and the C2 capacitor filtering of rectifier diode D4, the 5 pin places of LM348N just form a more stable direct voltage, amplifier chip LM348N_3 forms voltage comparator, by the adjustment of potentiometer WS-1, form the 5th pin of LM348N and the voltage compare of the 6th pin, when adjusting the voltage that WS-1 makes the voltage of the 5th pin higher than the 6th pin, 7th pin of LM348N exports as high level, now, D1 lamp is bright, D2 lamp goes out, buzzer is quiet, show normal work.In order to can Normal Alarm, prevent from arranging false alarm or failing to report police, need adjustment potentiometer WS-1 to criticality alarm position, namely the 6th pin voltage of LM348N be just lower than the 5th pin voltage, does not now report to the police; If the audio amplifier generation open circuit of series connection access or damage (burning), input R1 does not just have electric current to flow through, the voltage of the 5th pin of amplifier chip LM348N can drag down instantaneously, lower than the 6th pin voltage, now the 7th pin output low level, D1 lamp goes out, and D2 lamp is bright, buzzer sounding, shows have audio amplifier to break down.Equally, if by this device series connection access radio network basic routing line, because the disconnection of certain or some audio amplifiers can make the electric current flowing through resistance R1 diminish, the 5th pin voltage step-down of LM348N also can be caused, thus the magnitude of voltage of the 6th pin lower than critical condition, enter alarm condition.
Claims (6)
1. a multitone case fault detection system, it is characterized in that: comprise differential amplifier circuit (1), second level discharge circuit (2), voltage comparator (4) and failure alarm circuit (8), two signal ends of differential amplifier circuit are series in the audio loop of multitone case, and differential amplifier circuit inputs to the input of second level discharge circuit after being amplified by differential signal; The output of second level discharge circuit is provided with current rectifying and wave filtering circuit (3), after the signal rectification that current rectifying and wave filtering circuit exports second level discharge circuit, filtering, input to the in-phase input end of voltage comparator, the inverting input of voltage comparator is connected on power supply (6) through potentiometer (5); Failure alarm circuit is connected on the output of voltage comparator;
During use, the signal end of differential amplifier circuit is series at after in audio loop, makes the voltage of voltage comparator inverting input be greater than the voltage of in-phase input end by the resistance of regulator potentiometer, make failure alarm circuit send alarm signal; Then by changing the resistance of potentiometer until failure alarm circuit is not reported to the police just;
When audio loop generation open circuit or when having audio amplifier to disconnect, differential signal to be amplified can be made to reduce, the voltage inputing to voltage comparator in-phase input end also diminishes thereupon, the voltage of in-phase input end is made to be less than the voltage of inverting input, the output state of voltage comparator changes, failure alarm circuit sends alarm signal, has audio amplifier to produce fault to point out staff.
2. multitone case fault detection system according to claim 1, is characterized in that: described differential amplifier circuit (1), second level discharge circuit (2) and voltage comparator (4) are made up of the first operational amplifier (9), the second operational amplifier (10) and the 3rd operational amplifier (11) respectively;
The homophase of the first operational amplifier is connected with R2 through resistance R3, R1 successively with inverting input, be in series with resistance R4 between inverting input and output, the output signal of the first operational amplifier is connected to the in-phase input end of the second operational amplifier after the filter circuit that electric capacity C1 and resistance R6 forms;
The inverting input of the second operational amplifier is connected on positive source through resistance R5, output is connected to the in-phase input end of the 3rd operational amplifier successively through diode D4 and resistance R8, the inverting input of the second operational amplifier is connected to the junction of diode D4 and resistance R8 through resistance R7; The in-phase input end of the 3rd operational amplifier is connected to power supply on the ground through electric capacity C2 and resistance R9;
The anti-phase input of the 3rd operational amplifier is terminated on the armature contact of potentiometer (5), and potentiometer is being connected to power supply just and between power supply ground, output is connected with failure alarm circuit (8) after connecting with resistance R10.
3. multitone case fault detection system according to claim 2, it is characterized in that: described failure alarm circuit (8) is made up of light-emitting diode D2 and buzzer, the positive pole of diode D2 is connected to power supply on the ground, negative pole is connected with the output of the 3rd operational amplifier through resistance R11, and buzzer is connected to the output of the 3rd operational amplifier after connecting with resistance R12 and diode D3.
4. multitone case fault detection system according to claim 3, is characterized in that: also comprise the normal condition indicator light (7) be made up of light-emitting diode D1, and the positive pole of light-emitting diode D1, negative pole are connected on the negative pole of light-emitting diode D2, positive pole respectively.
5. the multitone case fault detection system according to Claims 2 or 3, is characterized in that: the resistance of described resistance R1 is 0.2 ~ 1.0 Ω.
6. the multitone case fault detection system according to Claims 2 or 3, is characterized in that: described first operational amplifier (9), the second operational amplifier (10) and the 3rd operational amplifier (11) are made up of 3 discharge circuits in amplifier chip LM348N.
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| CN201510101743.2A CN104661170A (en) | 2015-03-09 | 2015-03-09 | Fault detection system for multiple speakers |
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| CN201510101743.2A CN104661170A (en) | 2015-03-09 | 2015-03-09 | Fault detection system for multiple speakers |
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| CN201510101743.2A Pending CN104661170A (en) | 2015-03-09 | 2015-03-09 | Fault detection system for multiple speakers |
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Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN105592396A (en) * | 2015-12-23 | 2016-05-18 | 上海力申科学仪器有限公司 | Medical instrument loudspeaker abnormity on-line real-time alarm device |
| CN107770681A (en) * | 2017-11-23 | 2018-03-06 | 华中师范大学 | Adaptive volume controller and its method for controlling volume |
| CN108152543A (en) * | 2018-01-19 | 2018-06-12 | 国网江苏省电力有限公司宿迁供电分公司 | A kind of electric energy metering wiring box with fault alarm function |
| CN108919032A (en) * | 2018-07-26 | 2018-11-30 | 深圳市宇顺电子股份有限公司 | A kind of Mesh line test circuit and test method |
| CN109342854A (en) * | 2018-11-23 | 2019-02-15 | 重庆市钟表有限公司 | A kind of test circuit and method detecting machine core audio function |
| CN109417663A (en) * | 2016-04-28 | 2019-03-01 | 霍尼韦尔国际公司 | Earphone system fault detection |
| CN110996243A (en) * | 2019-12-16 | 2020-04-10 | 广州市迪士普音响科技有限公司 | Loudspeaker on-line detection system |
| CN112672266A (en) * | 2020-12-21 | 2021-04-16 | 北京云迹科技有限公司 | Abnormal sound box determination method and device |
| CN113885479A (en) * | 2021-10-27 | 2022-01-04 | 杭州和利时自动化有限公司 | Valve control circuit and diagnostic circuit of valve control circuit |
| CN114152777A (en) * | 2021-11-19 | 2022-03-08 | 中国北方发动机研究所(天津) | Circuit for testing and automatically detecting magnetoelectric rotation speed sensor |
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| CN109342854A (en) * | 2018-11-23 | 2019-02-15 | 重庆市钟表有限公司 | A kind of test circuit and method detecting machine core audio function |
| CN110996243A (en) * | 2019-12-16 | 2020-04-10 | 广州市迪士普音响科技有限公司 | Loudspeaker on-line detection system |
| CN112672266A (en) * | 2020-12-21 | 2021-04-16 | 北京云迹科技有限公司 | Abnormal sound box determination method and device |
| CN113885479A (en) * | 2021-10-27 | 2022-01-04 | 杭州和利时自动化有限公司 | Valve control circuit and diagnostic circuit of valve control circuit |
| CN113885479B (en) * | 2021-10-27 | 2024-03-01 | 杭州和利时自动化有限公司 | Valve control circuit and diagnostic circuit thereof |
| CN114152777A (en) * | 2021-11-19 | 2022-03-08 | 中国北方发动机研究所(天津) | Circuit for testing and automatically detecting magnetoelectric rotation speed sensor |
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