CN103674843B - Photoelectric smoke detector and using method thereof - Google Patents
Photoelectric smoke detector and using method thereof Download PDFInfo
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Abstract
The invention provides a kind of photoelectric smoke detector, its signal processing unit amplifies according to the receive from calibration control unit first or second yield value, described photoelectric smoke detector also comprises long term drift monitoring means, the long term drift of described long term drift monitoring means to the signal that photoelectric mist probe unit exports is monitored, and exporting monitoring information to described calibration control unit, described calibration control unit is sent to described signal processing unit after compensating described first yield value according to described monitoring information.Present invention also offers the using method of this detector.Photoelectric smoke detector of the present invention and using method thereof, the rapid drift impact of detector can be eliminated when each detection, by can eliminate the impact of long term drift every set time execution long term drift monitoring and compensation process, ensure that the accurate of the result of detection of photoelectric smoke detector and reliability.Further, circuit structure is simple and easy to realize.
Description
Technical field
The present invention relates to a kind of smoke detector and using method thereof of photoelectric type.
Background technology
In prior art, the structure of photoelectric smoke detector as shown in Figure 1; comprise photoelectric mist probe unit 100, signal processing unit 300, detecting signal unit 400 and calibration control unit 500, usually also comprise luminotron driver element 200, alarm control module 600 and timing control unit 700.
Photoelectric mist probe unit 100 comprises and is arranged on luminotron 101 in photoelectric mist detection cavity and photoelectric receiving tube 102.Photoelectric mist detection cavity is play the cavity hiding the protective effect of dirt lucifuge.Photoelectric receiving tube 102 is used for receiving the light signal that sends of luminotron 101 and being converted into electric signal.
Signal processing unit 300 comprises integrator 302, amplifier 303 and biasing circuit 301, is used for carrying out anomalous integral amplification to the electric signal that photoelectric receiving tube 102 exports.Integrator 302 can be integrator, trans-impedance amplifier, electric capacity or resistance.
Detecting signal unit 400 comprises DAC401 and comparer 402, the preset value stored in the preset value storer 502 of calibration control unit 500 is converted to simulation preset value by DAC401, thus can analog threshold be obtained, the simulating signal that this analog threshold and signal processing unit 300 export compares by comparer 402.
Calibration control unit 500 also comprises controller 501, for calibrating amplifier 303 and controlling.
For diffuse transmission type photoelectric mist detection cavity, the light that luminotron 101 sends can not shine directly into photoelectric receiving tube 102.When there being smog, just photoelectric receiving tube 102 can be incided by the light of smoke particle scattering.After the electric signal of signal processing unit 300 to input amplifies, the threshold value prestored through detecting signal unit 400 and calibration control unit 500 compares.If light signal is higher than threshold value, then sounded by alarm control module 600, visible ray etc. points out alerting signal.
For direct-projection type photoelectric smoke detection chamber, smoke particle can weaken the incident light of photoelectric receiving tube 102.After the electric signal of signal processing unit 300 to input amplifies, the threshold value prestored through detecting signal unit 400 and calibration control unit 500 compares.If light signal is lower than threshold value, then sounded by alarm control module 600, visible ray etc. points out alerting signal.
The optoelectronic components arranged in photoelectric mist detection cavity is very responsive to ambient environmental factors, the grit etc. in such as temperature, illumination and air.Meanwhile, also there is the problem producing degeneration because of Long-Time Service in optoelectronic components.These environmental factors and service factor finally show as the drift of the output signal of photoelectric receiving tube 102, make the result of detection inaccurate, even cause false triggering.Therefore, need the drift to these environmental factors and service factor cause to monitor, and the drift of signal is compensated accordingly.
Summary of the invention
In order to monitor the signal drift of existing photoelectric smoke detector and compensate, the invention provides a kind of photoelectric smoke detector, comprise photoelectric mist probe unit, signal processing unit, detecting signal unit and calibration control unit, described photoelectric mist probe unit sends light signal according to the smoke condition in air and is converted to electric signal, described signal processing unit receives this electric signal and amplifies, described detecting signal unit detects the signal that described signal processing unit exports, described signal processing unit carries out described amplification according to the receive from described calibration control unit first or second yield value, described photoelectric smoke detector also comprises long term drift monitoring means, the long term drift of described long term drift monitoring means to the light signal that described photoelectric mist probe unit exports is monitored, and export monitoring information to described calibration control unit, described calibration control unit is sent to described signal processing unit after compensating described first yield value according to described monitoring information.
Further, described long term drift monitoring means comprises low-pass filter and comparer, wherein, described low pass filter arrangement is that the detection signal exported described detecting signal unit carries out low-pass filtering to obtain signal envelope value, and described signal envelope value is transferred to described comparer; Described comparator arrangement is the drift standard value stored in described signal envelope value and described calibration control unit compared, and comparative result is exported to described calibration control unit as described monitoring information.
Further, described long term drift monitoring means also comprises data strobe switch, be configured to when performing long term drift calibration process that described data strobe switch connection is with low-pass filter described in bypass, when performing long term drift monitoring and compensation process, described data strobe switch disconnects to make described low-pass filter not be bypassed.
Further, described calibration control unit comprises algorithmic controller, the described monitoring information that described algorithmic controller is configured to according to receiving compensates described first yield value, if comparative result is described signal envelope value be greater than described drift standard value, described first yield value is increased by the first scheduled volume, otherwise described first yield value is reduced by the second scheduled volume.
Further, described calibration control unit also comprises: store the first gain memory of described first yield value and store the second gain memory of described second yield value, described first and second gain memories are nonvolatile memory; Data select switch, it connects for alternatively the described first or second yield value is exported to described signal processing unit, described data select switch be configured to when perform smoke detection process time export described first yield value, when perform long term drift monitoring and compensation process and long term drift calibration process time export described second yield value.
Further, described signal processing unit comprises variable gain amplifier, and the gain amplifier of described variable gain amplifier is connected to described data select switch to receive the described first or second yield value.
Present invention also offers a kind of using method of photoelectric smoke detector, the method comprises the long term drift performed every the set time after the unpacking of described photoelectric smoke detector uses and monitors and compensation process: calibration control unit described in S11. exports the second yield value to described signal processing unit, and makes the low-pass filter of described long term drift monitoring means be in the state be not bypassed; S12. described photoelectric smoke detector detects bias light; S13. described long term drift monitoring means carries out low-pass filtering to obtain signal envelope value to the detection signal that described detecting signal unit exports, and described signal envelope value and drift standard value are compared, comparative result is exported to described calibration control unit as described monitoring information; S14. described calibration control unit compensates described first yield value according to the described monitoring information received, if comparative result is described signal envelope value be greater than described drift standard value, described first yield value is increased by the first scheduled volume, otherwise described first yield value is reduced by the second scheduled volume.
Further, the method also comprises long term drift calibration process: the second yield value described in S21. initialization is the minimum value in its span; S22. described calibration control unit exports the second yield value to described signal processing unit, and makes the low-pass filter of described long term drift monitoring means be in the state be bypassed; S23., under non smoke air and standard temperature condition, described photoelectric smoke detector detects; S24. the preset standard value stored in the detection signal that exported by described detecting signal unit of described long term drift monitoring means and described calibration control unit compares; If S25. comparative result is that described detection signal is greater than described preset standard value, then using described detection signal as drift standard value, described second yield value as the second yield value after calibration, otherwise is increased by the 3rd scheduled volume and returns step S23 by described second yield value now.
Further, the method also comprises smoke detection process: calibration control unit described in S31. exports the first yield value to described signal processing unit; S32. extinguish the luminotron of described photoelectric mist probe unit, described photoelectric smoke detector detects; S33. the detection signal exported by described detecting signal unit is as rapid drift signal; S34. according to the preset value stored in described calibration control unit and described rapid drift signal, threshold value is calculated; S35. light the luminotron of described photoelectric mist probe unit, described photoelectric smoke detector detects; S36. described detecting signal unit is compared by the signal that exported by described signal processing unit and described threshold value, to obtain result of detection.
Photoelectric smoke detector of the present invention and using method thereof, the rapid drift impact of detector can be eliminated when each detection, by can eliminate the impact of long term drift every set time execution long term drift monitoring and compensation process, ensure that the accurate of the result of detection of photoelectric smoke detector and reliability.Further, circuit structure is simple and easy to realize.
Accompanying drawing explanation
Fig. 1 is the structural representation of the photoelectric smoke detector of prior art;
Fig. 2 is the structural representation preferred embodiment of photoelectric smoke detector of the present invention;
Fig. 3 is the process flow diagram of the smoke detection process preferred embodiment of the using method of photoelectric smoke detector of the present invention;
Fig. 4 is the monitoring of long term drift preferred embodiment of the using method of photoelectric smoke detector of the present invention and the process flow diagram of compensation process;
Fig. 5 is the process flow diagram of the long term drift calibration process preferred embodiment of the using method of photoelectric smoke detector of the present invention.
Embodiment
Below in conjunction with the drawings and specific embodiments, photoelectric smoke detector of the present invention and using method thereof are described in further detail, but not as a limitation of the invention.
With reference to Fig. 2, photoelectric smoke detector of the present invention comprises photoelectric mist probe unit 100, luminotron driver element 200, signal processing unit 300, detecting signal unit 400, calibration control unit 500, alarm control module 600, timing control unit 700 and long term drift monitoring means 800.Photoelectric mist probe unit 100 sends light signal according to the smoke condition in air, and signal processing unit 300 receives this light signal and carries out changing and amplifying, and the signal that detecting signal unit 400 pairs of signal processing units 300 export detects.
In this embodiment, signal processing unit 300 comprises variable gain amplifier 303 ', the gain amplifier of this variable gain amplifier 303 ' is connected to the data select switch 504-00 of calibration control unit 500, and namely the gain amplifier of variable gain amplifier 303 ' is subject to the control of the yield value of calibration control unit 500 output.
Calibration control unit 500 comprises the first gain memory 504-01 and the second gain memory 504-02, is nonvolatile memory.Store the first yield value in first gain memory 504-01, in the second gain memory 504-02, store the second yield value.Calibration control unit 500 also comprises data select switch 504-00, and two input end is connected respectively to the first gain memory 504-01 and the second gain memory 504-02, and an output terminal is connected to variable gain amplifier 303 '.Data select switch 504-00 is configured to the gain control end the first yield value and the second yield value alternatively being exported to variable gain amplifier 303 ', when perform smoke detection process time export the first yield value, when perform long term drift monitoring and compensation process and long term drift calibration process time export the second yield value.
Long term drift monitoring means 800 is monitored for the long term drift of the light signal exported photoelectric mist probe unit 100, and exports monitoring information to calibration control unit 500.Long term drift refers to the drift of the signal caused due to the changing factor at a slow speed such as device aging, seasonal variations.Long term drift monitoring means 800 comprises low-pass filter 801 and comparer 802, wherein, the detection signal that low-pass filter 801 is configured to detecting signal unit 400 exports carries out low-pass filtering to obtain signal envelope value, and this signal envelope value is transferred to comparer 802.The drift standard value that comparer 802 is configured to store in the drift standard value storer 503 by signal envelope value and calibration control unit 500 compares, and comparative result is exported to calibration control unit 500 as monitoring information.Long term drift monitoring means 800 also comprises data strobe switch 803, when performing long term drift calibration process, data strobe switch 803 is connected with bypass low-pass filter 801, and when performing long term drift monitoring and compensation process, data strobe switch 803 disconnects low-pass filter 801 is not bypassed.
Calibration control unit 500 also comprises algorithmic controller 501-01, the monitoring information that algorithmic controller 501-01 is configured to according to receiving compensates the first yield value, be greater than drift standard value if comparative result is signal envelope value, the first yield value increased by the first scheduled volume, otherwise the first yield value is reduced by the second scheduled volume.Calibration control unit 500 also comprises memory read/write controller 501-00, for control algolithm controller 501-01 to the read and write access of each storer.
Before photoelectric smoke detector dispatches from the factory, execution is needed to dispatch from the factory test process, to determine the drift initial value of standard value and the initial value of the second yield value.The initial value of the first yield value is determined by the characteristic of photoelectric device.
As shown in Figure 3, be the process flow diagram of the smoke detection process preferred embodiment of the using method of photoelectric smoke detector of the present invention.This process comprises: step S31, and data strobe switch 504-00 is switched to the first gain memory 504-01, and data strobe switch 803 is connected low-pass filter 801 bypass.Step S32, extinguish luminotron 101, photoelectric smoke detector detects.Step S33, the detection signal exported by detecting signal unit 400 is as rapid drift signal D
z.Rapid drift refers to the signal drift that the fast-changing factors such as fast-changing temperature, bias light cause, also referred to as noise.Different from long term drift, the impact of rapid drift needs to remove immediately in each detection.Step S34, according to the preset value D stored in the preset value storer 502 of calibration control unit 500
lMTwith rapid drift signal D
z, calculate threshold value D
tH=D
z+ D
lMT.Step S35, light luminotron 101, photoelectric smoke detector detects.Step S36, the signal D that signal processing unit 300 exports by detecting signal unit 400
swith threshold value D
tHcompare, obtain result of detection.The signal D received
sin not only comprised light input signal that needs detect but also comprised noise signal D
z, therefore by signal D
swith the same threshold value D comprising noise signal
tHcompare, can the impact of stress release treatment signal, namely eliminate the impact of rapid drift.Be understandable that, the method that eliminating rapid drift affects is not limited to the method that present embodiment provides, such as, and can also by rapid drift signal D
zfrom signal D
smiddle removal, and then with preset value D
lMTrelatively.
As shown in Figure 4, be the monitoring of long term drift preferred embodiment of the using method of photoelectric smoke detector of the present invention and the process flow diagram of compensation process.Photoelectric smoke detector, after unpacking uses, every the set time, just needs to perform long term drift monitoring and compensation process, so that the impact of long term drift removed.This process comprises: step S11, and data strobe switch 504-00 is switched to the second gain memory 504-02, and data strobe switch 803 disconnects, and makes low-pass filter 801 be in the state be not bypassed.Step S12, photoelectric smoke detector detects bias light.Step S13, the detection signal that low-pass filter 801 pairs of detecting signal units 400 export carries out low-pass filtering to obtain signal envelope value, and the drift standard value stored in this signal envelope value and drift standard value storer 503 is compared, comparative result is exported to calibration control unit 500 as monitoring information.Step S14, algorithmic controller 501-01 in calibration control unit 500 compensates the first yield value according to the monitoring information received, be greater than drift standard value if comparative result is signal envelope value, the first yield value increased by the first scheduled volume, otherwise described first yield value is reduced by the second scheduled volume.This process, by adjustment first yield value, compensates the long term drift of detector, effectively can eliminate the impact of long term drift on smoke detector.
As shown in Figure 5, be the process flow diagram of the long term drift calibration process preferred embodiment of the using method of photoelectric smoke detector of the present invention.Long term drift calibration process is used for calibrating the second yield value, thus plays the effect of calibrating long term drift monitoring and compensation process.Particularly, this process comprises: step S21, and the second yield value is initialized as the minimum value in its span.Step S22, switches to the second gain memory 504-02 by data strobe switch 504-00, and data strobe switch 803 is connected low-pass filter 801 bypass.Step S23, under non smoke air and standard temperature condition, photoelectric smoke detector detects.Step S24, the preset standard value stored in the preset standard value storer 503 ' of the detection signal that detecting signal unit 400 exports by long term drift monitoring means 800 and calibration control unit 500 compares.This preset standard value determines according to the photoelectric characteristic of photoelectric device and aging characteristics, and this value is larger, compensate and the precision of calibration higher.Step S25, if comparative result is detection signal be greater than preset standard value, then detection signal is write drift standard value storer 503 as drift standard value, described second yield value now writes in the second yield value storer 504-02 as the second yield value after calibration, otherwise the first yield value is increased by the 3rd scheduled volume and returns step S23.This calibration flow process can have been controlled by the algorithmic controller 501-01 of calibration control unit 500, also automatically can be completed by other circuit in photoelectric smoke detector chip, can also have been come by the artificial of outside or computer software.
Above embodiment is only illustrative embodiments of the present invention, can not be used for limiting the present invention, and protection scope of the present invention is defined by the claims.Those skilled in the art can in essence of the present invention and protection domain, and make various amendment or equivalent replacement to the present invention, these are revised or be equal to replacement and also should be considered as dropping in protection scope of the present invention.
Claims (8)
1. a photoelectric smoke detector, comprise photoelectric mist probe unit, signal processing unit, detecting signal unit and calibration control unit, described photoelectric mist probe unit sends light signal according to the smoke condition in air and is converted to electric signal, described signal processing unit receives this electric signal and amplifies, described detecting signal unit detects the signal that described signal processing unit exports
It is characterized in that, described signal processing unit carries out described amplification according to the receive from described calibration control unit first or second yield value, described photoelectric smoke detector also comprises long term drift monitoring means, the long term drift of described long term drift monitoring means to the electric signal that described photoelectric mist probe unit exports is monitored, and export monitoring information to described calibration control unit, described calibration control unit is sent to described signal processing unit after compensating described first yield value according to described monitoring information
Described long term drift monitoring means comprises low-pass filter and comparer, wherein,
Described low pass filter arrangement is that the detection signal exported described detecting signal unit carries out low-pass filtering to obtain signal envelope value, and described signal envelope value is transferred to described comparer;
Described comparator arrangement is the drift standard value stored in described signal envelope value and described calibration control unit compared, and comparative result is exported to described calibration control unit as described monitoring information.
2. photoelectric smoke detector according to claim 1, it is characterized in that, described long term drift monitoring means also comprises data strobe switch, be configured to when performing long term drift calibration process that described data strobe switch connection is with low-pass filter described in bypass, when performing long term drift monitoring and compensation process, described data strobe switch disconnects to make described low-pass filter not be bypassed.
3. photoelectric smoke detector according to claim 1, it is characterized in that, described calibration control unit comprises algorithmic controller, the described monitoring information that described algorithmic controller is configured to according to receiving compensates described first yield value, if comparative result is described signal envelope value be greater than described drift standard value, described first yield value is increased by the first scheduled volume, otherwise described first yield value is reduced by the second scheduled volume.
4. photoelectric smoke detector according to claim 1, is characterized in that, described calibration control unit also comprises:
Store the first gain memory of described first yield value and store the second gain memory of described second yield value, described first and second gain memories are nonvolatile memory;
Data select switch, it connects for alternatively the described first or second yield value is exported to described signal processing unit, described data select switch be configured to when perform smoke detection process time export described first yield value, when perform long term drift monitoring and compensation process and long term drift calibration process time export described second yield value.
5. photoelectric smoke detector according to claim 4, it is characterized in that, described signal processing unit comprises variable gain amplifier, and the gain amplifier of described variable gain amplifier is connected to described data select switch to receive the described first or second yield value.
6. a using method for photoelectric smoke detector according to claim 1, is characterized in that, the method comprises the long term drift performed every the set time after the unpacking of described photoelectric smoke detector uses and monitors and compensation process:
S11. described calibration control unit exports the second yield value to described signal processing unit, and makes the low-pass filter of described long term drift monitoring means be in the state be not bypassed;
S12. described photoelectric smoke detector detects bias light;
S13. described long term drift monitoring means carries out low-pass filtering to obtain signal envelope value to the detection signal that described detecting signal unit exports, and described signal envelope value and drift standard value are compared, comparative result is exported to described calibration control unit as described monitoring information;
S14. described calibration control unit compensates described first yield value according to the described monitoring information received, if comparative result is described signal envelope value be greater than described drift standard value, described first yield value is increased by the first scheduled volume, otherwise described first yield value is reduced by the second scheduled volume.
7. the using method of photoelectric smoke detector according to claim 6, is characterized in that, the method also comprises long term drift calibration process:
S21. the second yield value described in initialization is the minimum value in its span;
S22. described calibration control unit exports the second yield value to described signal processing unit, and makes the low-pass filter of described long term drift monitoring means be in the state be bypassed;
S23., under non smoke air and standard temperature condition, described photoelectric smoke detector detects;
S24. the preset standard value stored in the detection signal that exported by described detecting signal unit of described long term drift monitoring means and described calibration control unit compares;
If S25. comparative result is that described detection signal is greater than described preset standard value, then using described detection signal as drift standard value, described second yield value as the second yield value after calibration, otherwise is increased by the 3rd scheduled volume and returns step S23 by described second yield value now.
8. the using method of photoelectric smoke detector according to claim 6, is characterized in that, the method also comprises smoke detection process:
S31. described calibration control unit exports the first yield value to described signal processing unit;
S32. extinguish the luminotron of described photoelectric mist probe unit, described photoelectric smoke detector detects;
S33. the detection signal exported by described detecting signal unit is as rapid drift signal;
S34. according to the preset value stored in described calibration control unit and described rapid drift signal, threshold value is calculated;
S35. light the luminotron of described photoelectric mist probe unit, described photoelectric smoke detector detects;
S36. described detecting signal unit is compared by the signal that exported by described signal processing unit and described threshold value, to obtain result of detection.
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| EP3290905B1 (en) * | 2016-09-05 | 2022-10-19 | F. Hoffmann-La Roche AG | Signal offset determination and correction |
| CN107991433B (en) * | 2017-11-09 | 2021-07-06 | 广州视源电子科技股份有限公司 | Smoke value processing method and system, readable storage medium and smoke processing equipment |
| EP3489921B1 (en) * | 2017-11-24 | 2020-01-01 | Siemens Schweiz AG | Method and device for configuring a smoke detector |
| CN109448304B (en) * | 2018-12-18 | 2021-05-28 | 上海贝岭股份有限公司 | Method and system for calibrating threshold value of smoke alarm |
| CN110675591B (en) * | 2019-09-14 | 2021-04-30 | 杭州拓深科技有限公司 | Anti-interference photoelectric smoke detection method and detection module |
| US11127284B1 (en) * | 2020-07-02 | 2021-09-21 | Honeywell International Inc. | Self-calibrating fire sensing device |
| CN113514380A (en) * | 2021-07-06 | 2021-10-19 | 深圳市豪恩安全科技有限公司 | High-precision smoke detection method and device |
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