CN2874472Y - Smoke concentration detector - Google Patents
Smoke concentration detector Download PDFInfo
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- CN2874472Y CN2874472Y CN 200520091905 CN200520091905U CN2874472Y CN 2874472 Y CN2874472 Y CN 2874472Y CN 200520091905 CN200520091905 CN 200520091905 CN 200520091905 U CN200520091905 U CN 200520091905U CN 2874472 Y CN2874472 Y CN 2874472Y
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- laser
- smog
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- detecting chamber
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Abstract
A smog density detecting device belonging to the fire detector alarming technical field is provided, which comprises an air filter, a semi-conductor laser, laser beam space proofreading lens, a light beam space wave filtering diaphragm, a detecting room, a detecting room support, a smog radiation detector, a laser power detector, an extinction mechanism, a reflection plate, and a shell. The semi-conductor laser and the laser beam space proofreading lens are connected with each other through screw threads, and the semi-conductor laser is positioned on a detector room support through bolts. The light beam space wave filtering diaphragm is embedded at one side of the laser beam space proofreading lens in the detecting room. The extinction mechanism is embedded at another side of detecting room symmetrical with the laser beam space proofreading lens. The reflection plate is positioned at the front of the extinction plate, and the laser power detector is positioned at the upper position of the main light beam radiating point of the reflection plate. The smog radiation detector is arranged in the upper wall of the detecting room. The above arts are assembled and arranged in the shell, and the air inlet of the shell is provided with air filter.
Description
Technical field
The utility model belongs to the fire detecting and alarm technical field, particularly a kind of smoke concentration detector.
Background technology
Along with China's development of economic construction, some play special place (as computing center, picture and text archives information center, post and telecommunications hinge, integrated circuit workshop, nuclear power station, large-scale modernized dispatching control center, intelligent building control center, modern medical service mechanism etc.) the security against fire demand of most important effect in national economy and social life urgent day by day.Since its inner various electrical equipment high concentration and long-term work operation, thus there is more fire hidden danger, in case breaking out of fire will cause great economic loss to country, bring significant impact to society.In view of the importance and the singularity in these places, the super early fire detection warning problem in these places has become one of emphasis of security against fire, causes people's very big concern.
At present, the smoke detector of the general type of these place widespread uses, owing to be subjected to the not restriction of high factor of detection sensitivity, utmost point early detection scarce capacity for fire, basically the affirmation that belongs to fire is surveyed, be difficult to play the forecast and the fire prevention effect of fire, can not satisfy the requirement that the super early detection of fire is reported to the police.In order to improve the fire forecast pre-alerting ability of fire detector, developed attraction type high sensitivity smoke detection technology in the world.U.S. Honeywell Inc. has developed a kind of some type high sensitive smoke detector at present, it can identify the potential condition of a fire at the fire commitment, realizes the fire alarm, and this helps in time to take measures, prevent fire in possible trouble, thereby economic loss is minimized.
Similar with a type high sensitivity smoke detection device, the utility model device also adopts smog light scattering detection principle to carry out the smokescope photodetection.Different with it is that the utility model device has adopted semiconductor laser, has designed special light beam space constraint assembly, unique detection cell structure and delustring device, makes sensing chamber form extremely dark background; Designed the scatter sounding angle that is different from other forward direction sniffers, made it all responsive for various smog; By the high-performance optical electrical signal conversion circuit of uniqueness, realized the high sensitivity smoke detection; The utility model device has also designed the testing circuit of laser output power, with the drift of monitoring laser power.This device detection sensitivity is high, can effectively detect the particle of cable wrap thermal decomposition volatilization, and the enough strong detectable signal of output.
The utility model content
At the deficiencies in the prior art, the utility model provides a kind of smoke concentration detector, this device is for the sensitivity that improves smoke and survey designs, and comprises an air strainer, semiconductor laser, laser beam space correcting lens, one group of light beam spatial filtering diaphragm, detecting chamber, detecting chamber support, smog scattering detector, laser power detector, extinction machanism, reflecting plate, shell.
Wherein, detecting chamber support and detecting chamber are fixed as one; Semiconductor laser and laser beam space correcting lens are integral by being threaded, and semiconductor laser on the detecting chamber support, and can be finely tuned the position of semiconductor laser by the degree of tightness that 4 screws screw in by 4 screw retention up and down; Detecting chamber embeds one group of light beam spatial filtering diaphragm near a side of laser beam space correcting lens, this group light beam spatial filtering diaphragm has 4, the position of detecting chamber opposite side and light beam spatial filtering diaphragm symmetry embeds extinction machanism, and wherein the center of semiconductor laser, laser beam space correcting lens, light beam spatial filtering diaphragm and extinction machanism is positioned on the beam axis simultaneously; Front at extinction machanism is provided with reflecting plate, and the angle of reflecting plate and detecting chamber is 135 °; On the vertical direction of the main beam incidence point of reflecting plate, be provided with laser power detector; Upper wall at detecting chamber is provided with smog scattering detector mounting hole, and the hole is embedded in the smog scattering detector, be used to accept with beam axis to the smog scattered light that is 90 °; Pack into after the whole assembling of above-mentioned parts forms in the shell, and be screwed bottom, insert air strainer at the air intake opening end of shell at shell.
The superiority of this structure has been to realize the utmost point dark background design of smoke detection, has guaranteed the requirement of high sensitivity smog scatter sounding to background; Sidewise scattered smoke detection design makes that various smoke detectors are had comparatively balanced response performance; And the pollution can effectively resist the detecting chamber long-time running time is to the influence of highly sensitive detection, disturbs for the dust under the usual conditions and water smoke to have certain wrong report immunity.
In the utility model device, the photosignal of smog scattering detector is implemented photocurrent-voltage signal conversion by smog scatter sounding circuit and is amplified; The photosignal of laser power detector is implemented photocurrent-voltage signal conversion by the laser power detection circuit and is amplified; Semiconductor laser is implemented control of the light emitting drive of lasing fluorescence/and laser perseverance output power FEEDBACK CONTROL by laser drive circuit.
The concrete annexation of foregoing circuit is as follows:
Smog scatter sounding circuit theory is: the reverse input end 6,2 that the smog scattering detector is connected to two unit of double operational U2; The input end in the same way 5,3 of U2 connects the voltage reference that is made of R1, U1, and U1 can some filter capacitors in parallel; Be connected a big resistance current/voltage respectively in the reverse input 6,2 of two unit of U2 and 7,1 corresponding of output and change build-out resistor R2 and R3, convert the photo-signal of smog scattering detector to voltage signal; R2 and R3 can filter capacitors in parallel; The output 7,1 of U2 is connected respectively to the reverse input 2 of differential amplifier U3 and imports in the same way in 3, implements calculus of differences and amplifies; Its anti-big gain is provided with by 1,8 resistance R 4 that is connected U3 and the resistance R 6 that is connected 5 and the circuit ground of U3, and R6 also connects an electric capacity.The output 6 of U3 is by outwards exporting smog scatter sounding signal after the RC filtering.The power input of the amplifier of this circuit all is provided with RC filtering.
The superiority of this circuit is to use extremely simple, novel design to realize the photosignal conversion of high s/n ratio and signal is counter amplifies, this circuit has the superpower inhibition ability and the single supply work of common mode interference, the characteristic of rail-to-rail output, the imbalance of circuit output is less than 10mV under the situation of full dark background illumination, and the photocurrent detectivity of circuit is 2.5pA.
The laser power detection circuit is classical circuit, as shown in Figure 9, does not turn round and look at and introduces in detail.
The laser drive circuit principle is: the inner connection of cathode is packaged together altogether with the PD unit in the LD unit of laser instrument, the LD anode is connected+5V, LD also meets a protection diode D1, and common cathode connects the collector of power drive triode N1, N1 emitter connection circuit ground by a current-limiting resistance R3; The PD anode connects+5V by an electric capacity, by resistance R 2 and adjustable potentiometer VR1 connection circuit ground, is connected to the base stage of FEEDBACK CONTROL triode P1 simultaneously, and VR1 can regulate the output of laser power; The collector of P1 connects the base stage of N1; The emitter of P1 connects+5V by resistance R 1.By N2 and P2 is that main ON-OFF control circuit is connected outside light emitting drive Transistor-Transistor Logic level signal, and the P1 emitter current potential that the collector of control D2 connects is implemented luminous and non-luminous control to laser instrument.
The superiority of this circuit is that the setting that realizes laser power output is regulated and the control of permanent Output optical power, by VR1 can the setting laser device power output, by the power detection in real time of PD and the FEEDBACK CONTROL effect of circuit.Can make laser power at-15 ℃--in-+60 ℃ the temperature range, power output is controlled in the scope of 3W ± 0.3W, has greatly improved the temperature characterisitic of laser instrument.This circuit has also been realized the luminous and non-luminous drive controlling of laser instrument simultaneously.
Compare with the smoke monitoring device of common smoke point detector, the utility model device provides high detection sensitivity, broad spectrum activity, detecting chamber pollution and the certain dust and water smoke of response to disturb wrong report immunity.Simultaneously, this device provides the monitoring capability of laser power drift, makes external treatment partly implement the laser power drift compensation and the fault monitoring of laser works state is become possibility.
Description of drawings
Fig. 1 is the front view of detecting chamber;
Fig. 2 is the vertical view of detecting chamber;
Fig. 3 is the A-A directional profile figure of Fig. 2;
Fig. 4 is the sectional view of the utility model device;
Fig. 5 is the laser drive circuit block diagram;
Fig. 6 is the circuit block diagram of detecting module;
Fig. 7 is the laser drive circuit schematic diagram;
Fig. 8 is smog scatter sounding circuit theory diagrams;
Fig. 9 is a laser power detection circuit schematic diagram;
Wherein, 1 air strainer, 2 semiconductor lasers, 3 laser beam space correcting lenses, 4 light beam spatial filtering diaphragms, 5 detecting chambers, 6 detecting chamber supports, 7 shells, A smog scattering detector, B laser power detector, C extinction machanism, D reflecting plate.
Embodiment
Be described in detail below in conjunction with the embodiment of accompanying drawing the utility model device:
Shown in Fig. 1-4, the utility model device comprises an air strainer 1, semiconductor laser 2, laser beam space correcting lens 3, one group of light beam spatial filtering diaphragm 4, detecting chamber 5, detecting chamber support 6, smog scattering detector A, laser power detector B, extinction machanism C, reflecting plate D, shell 7.
Wherein, detecting chamber support 6 is fixed as one with detecting chamber 5; Semiconductor laser 2 and laser beam space correcting lens 3 are integral by being threaded, and semiconductor laser 2 on detecting chamber support 6, and can be finely tuned the position of semiconductor laser 2 by the degree of tightness that 4 screws screw in by 4 screw retention up and down; Detecting chamber 5 embeds one group of light beam spatial filtering diaphragm 4 near a side of laser beam space correcting lens 3, this group light beam spatial filtering diaphragm has 4, the position of detecting chamber 5 opposite sides and light beam spatial filtering diaphragm 4 symmetries embeds extinction machanism C, and wherein the center of semiconductor laser 2, laser beam space correcting lens 3, light beam spatial filtering diaphragm 4 and extinction machanism C is positioned on the beam axis simultaneously; Be provided with reflecting plate D in the front of extinction machanism C, the angle of reflecting plate D and detecting chamber 5 is 135 °; On the vertical direction of the main beam incidence point of reflecting plate D, be provided with laser power detector B; Upper wall at detecting chamber 5 is provided with smog scattering detector mounting hole, and the hole is embedded in smog scattering detector A, be used to accept with beam axis to the smog scattered light that is 90 °; Pack into after the whole assembling of above-mentioned parts forms in the shell 7, and be screwed, insert air strainer 1 at the air intake opening end of shell 7 in the bottom of shell 7.
Smog scatter sounding circuit theory is as follows, as shown in Figure 8:
The smog scattering detector is connected to the reverse input end 6,2 of two unit of double operational U2; The input end in the same way 5,3 of U2 connects the voltage reference that is made of R1, U1, and U1 can some filter capacitors in parallel; Be connected a big resistance current/voltage respectively in the reverse input 6,2 of two unit of U2 and 7,1 corresponding of output and change build-out resistor R2 and R3, convert the photo-signal of smog scattering detector to voltage signal; R2 and R3 can filter capacitors in parallel; The output 7,1 of U2 is connected respectively to the reverse input 2 of differential amplifier U3 and imports in the same way in 3, implements calculus of differences and amplifies; Its anti-big gain is provided with by 1,8 resistance R 4 that is connected U3 and the resistance R 6 that is connected 5 and the circuit ground of U3, and R6 also connects an electric capacity.The output 6 of U3 is by outwards exporting smog scatter sounding signal after the RC filtering.The power input of the amplifier of this circuit all is provided with RC filtering.
The smoke detection circuit can be implemented in such a way: smog scatter sounding circuit adopts P1313 as the smog scattering detector, a double operational U2 adopts LN1138 to make photocurrent voltage differential converter, build-out resistor R2, R3 adopt the metalfilmresistor in 20M Europe, and capacity in parallel respectively is 101 ceramic disc capacitor; Constitute voltage offset electric circuit by R1, U1, E1, C1; R1 is 10K, and U1 is voltage reference LM285-2.5, and E1 is that 10uF/10V tantalum electric capacity, C1 are 103 ceramic disc capacitors; Constitute and resistance is that the R4 of 10K and R6 that resistance is 200K constitute the differential ference spiral amplifying circuit by INA115; The RC parameter of output is that the R5 of 1K resistance and capacity are 224 leaded multilayer ceramic capacitor, makes that the output impedance of signal is 1K Europe.The power input of each amplifier is provided with a resistance and an electrochemical capacitor and the RC filtering device that ceramic disc capacitor constitutes, and resistance value is 10 ohm, and electrochemical capacitor can be 10uF/10V, and the ceramic disc capacitor capacity is 103.
The laser drive circuit principle is as follows, as shown in Figure 7:
The LD unit of laser instrument and PD unit are packaged together altogether inner connection of cathode, and the LD anode is connected+5V, and LD also connects one and protects diode D1, and common cathode connects the collector of power drive triode N1, N1 emitter connection circuit ground by a current-limiting resistance R3; The PD anode connects+5V by an electric capacity, by resistance R 2 and adjustable potentiometer VR1 connection circuit ground, is connected to the base stage of FEEDBACK CONTROL triode P1 simultaneously, and VR1 can regulate the output of laser power; The collector of P1 connects the base stage of N1; The emitter of P1 connects+5V by resistance R 1.By N2 and P2 is that main ON-OFF control circuit is connected outside light emitting drive Transistor-Transistor Logic level signal, and the P1 emitter current potential that the collector of control D2 connects is implemented luminous and non-luminous control to laser instrument.
Drive circuit for laser can be implemented in such a way: laser instrument is the RLD78MPT3 with inner PD, and N1 is S9014, and P1 is C9015, and N2 is C9013, and P2 is C9012, and current-limiting resistance R3 is 10 Europe, and feedback resistance R2 is that 6.2K, VR1 are 5K; The emitter resistance of P1 is 15K.Other device parameters can take the circumstances into consideration to choose.
Laser power detection circuit principle is as follows, as shown in Figure 9:
E5 and C13 constitute electric source filter circuit.Laser power detector PD1 is connected to two input ends 2,3 of an amplifier unit of double operational U6 U6A; The in-phase input end 3 of U6A connects the anode of PD1, and connect R7 to circuit ground, the inverting input 2 of U6A connects the negative electrode of PD1, and connection R8 is to the output terminal 1 of U6A, R7, R8 current/voltage conversion build-out resistor, with laser light electric current conversion of signals is voltage signal, and R7, R8 can a filter capacitor C11 in parallel, C12.The output terminal 1 of U6A connects R9, R10, C14 and connect circuit ground after the other end connect with R9 and constitute amplifier interstage coupling circuit, the in-phase input end 5 that connects another amplifier unit U6B of amplifier U6, at inverting input 6 and 7 of the output terminals of U6B and connect R11, C15, formation voltage follower circuit, output terminal 7 series connection R12 and C8 are to circuit ground, constitute filtering circuit, the junction that signal output P2 takes from R12 and C8.
The laser power detection circuit can be implemented in such a way: the laser power detection circuit adopts PD333-3C, and a double operational U6 adopts LM358, and build-out resistor R7, R8 adopt 3.3M Europe resistance, can capacity in parallel respectively is 102 electric capacity; R9 is 39K Europe, and R10 is 390K Europe, and C14 is 103 electric capacity; R11 is 33K, and C15 is 103 electric capacity; R12 is 1K, and output capacitance C8 is 224 electric capacity.
This circuit if no special instructions, it is 1/100 metalfilmresistor that all resistance R are precision.
The course of work of the utility model device is that this device makes the gas sample by air strainer 1 by outside air extractor, enters detecting chamber 5; Under the driving of laser drive circuit, semiconductor laser 2 sends laser, and laser beam is passed light beam spatial filtering diaphragm 4 and entered detecting chamber 5 by behind the laser beam space correcting lens 3, shines on the gas sample light scattering takes place; The smog scattering detector A that scattered light is installed in the detecting chamber sidewall receives; Main beam passes and passes the light beam spatial filtering diaphragm 4 plate D that is reflected behind the extinction machanism and reflex to laser power detector B and receive; Smog scatter sounding circuit and laser power detection circuit are exported smoke detection signal and laser power monitor signal respectively, and this output signal offers external unit and carries out signal Processing.
Claims (4)
1, a kind of smoke concentration detector, comprise an air strainer, semiconductor laser, laser beam space correcting lens, one group of light beam spatial filtering diaphragm, detecting chamber, detecting chamber support, smog scattering detector, laser power detector, extinction machanism, reflecting plate, shell, it is characterized in that detecting chamber support and detecting chamber are fixed as one in this device; Semiconductor laser and laser beam space correcting lens are integral by being threaded, and semiconductor laser on the detecting chamber support, and can be finely tuned the position of semiconductor laser by the degree of tightness that 4 screws screw in by 4 screw retention up and down; Detecting chamber embeds one group of light beam spatial filtering diaphragm near a side of laser beam space correcting lens, the position of detecting chamber opposite side and light beam spatial filtering diaphragm symmetry embeds extinction machanism, and wherein the center of semiconductor laser, laser beam space correcting lens, light beam spatial filtering diaphragm and extinction machanism is positioned on the beam axis simultaneously; Front at extinction machanism is provided with reflecting plate, and the angle of reflecting plate and detecting chamber is 135 °; On the vertical direction of the main beam incidence point of reflecting plate, be provided with laser power detector; Upper wall at detecting chamber is provided with smog scattering detector mounting hole, and the hole is embedded in the smog scattering detector, be used to accept with beam axis to the smog scattered light that is 90 °; Pack into after the whole assembling of above-mentioned parts forms in the shell, and be screwed bottom, insert air strainer at the air intake opening end of shell at shell;
The photosignal of smog scattering detector is implemented photocurrent-voltage signal conversion and amplification by smog scatter sounding circuit in the said apparatus; The photosignal of laser power detector is implemented photocurrent-voltage signal conversion by the laser power detection circuit and is amplified; Semiconductor laser is implemented control of the light emitting drive of lasing fluorescence/and laser perseverance output power FEEDBACK CONTROL by laser drive circuit.
2, a kind of smoke concentration detector according to claim 1 is characterized in that described one group of light beam spatial filtering diaphragm comprises 4 light beam spatial filtering diaphragms.
3, a kind of smoke concentration detector according to claim 1 is characterized in that described smog scatter sounding circuit theory is: the reverse input end 6,2 that the smog scattering detector is connected to two unit of double operational U2; The input end in the same way 5,3 of U2 connects the voltage reference that is made of R1, U1, and U1 can some filter capacitors in parallel; Be connected a big resistance current/voltage respectively in the reverse input 6,2 of two unit of U2 and 7,1 corresponding of output and change build-out resistor R2 and R3, convert the photo-signal of smog scattering detector to voltage signal; R2 and R3 can filter capacitors in parallel; The output 7,1 of U2 is connected respectively to the reverse input 2 of differential amplifier U3 and imports in the same way in 3, implements calculus of differences and amplifies; Its anti-big gain is provided with by 1,8 resistance R 4 that is connected U3 and the resistance R 6 that is connected 5 and the circuit ground of U3, and R6 also connects an electric capacity; The output 6 of U3 is by outwards exporting smog scatter sounding signal after the RC filtering; The power input of the amplifier of this circuit all is provided with RC filtering.
4, a kind of smoke concentration detector according to claim 1, it is characterized in that described laser drive circuit principle is: the inner connection of cathode is packaged together altogether with the PD unit in the LD unit of laser instrument, the LD anode is connected+5V, LD also meets a protection diode D1, common cathode connects the collector of power drive triode N1, N1 emitter connection circuit ground by a current-limiting resistance R3; The PD anode connects+5V by an electric capacity, by resistance R 2 and adjustable potentiometer VR1 connection circuit ground, is connected to the base stage of FEEDBACK CONTROL triode P1 simultaneously, and VR1 can regulate the output of laser power; The collector of P1 connects the base stage of N1; The emitter of P1 connects+5V by resistance R 1; By N2 and P2 is that main ON-OFF control circuit is connected outside light emitting drive Transistor-Transistor Logic level signal, and the P1 emitter current potential that the collector of control D2 connects is implemented luminous and non-luminous control to laser instrument.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 200520091905 CN2874472Y (en) | 2005-07-22 | 2005-07-22 | Smoke concentration detector |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 200520091905 CN2874472Y (en) | 2005-07-22 | 2005-07-22 | Smoke concentration detector |
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| Publication Number | Publication Date |
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| CN2874472Y true CN2874472Y (en) | 2007-02-28 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 200520091905 Expired - Lifetime CN2874472Y (en) | 2005-07-22 | 2005-07-22 | Smoke concentration detector |
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100427922C (en) * | 2005-07-22 | 2008-10-22 | 公安部沈阳消防研究所 | Smoke concentration detector |
| CN101801498B (en) * | 2007-08-08 | 2012-11-21 | 熊津豪威株式会社 | Rotary particle sensor assembly and an air cleaner having it |
| CN103076598A (en) * | 2012-12-31 | 2013-05-01 | 中国科学技术大学 | Experimental device used for researching influence of smoke on radar life detection signal |
| CN104459817A (en) * | 2014-12-16 | 2015-03-25 | 公安部沈阳消防研究所 | Fire sign detection device and method |
| CN104749075A (en) * | 2014-10-16 | 2015-07-01 | 北京汉王蓝天科技有限公司 | Air particle detecting device and method |
| CN106290089A (en) * | 2015-05-12 | 2017-01-04 | 杜晨光 | A kind of high-precision miniaturization particulate matter sensors |
-
2005
- 2005-07-22 CN CN 200520091905 patent/CN2874472Y/en not_active Expired - Lifetime
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100427922C (en) * | 2005-07-22 | 2008-10-22 | 公安部沈阳消防研究所 | Smoke concentration detector |
| CN101801498B (en) * | 2007-08-08 | 2012-11-21 | 熊津豪威株式会社 | Rotary particle sensor assembly and an air cleaner having it |
| CN103076598A (en) * | 2012-12-31 | 2013-05-01 | 中国科学技术大学 | Experimental device used for researching influence of smoke on radar life detection signal |
| CN104749075A (en) * | 2014-10-16 | 2015-07-01 | 北京汉王蓝天科技有限公司 | Air particle detecting device and method |
| CN104459817A (en) * | 2014-12-16 | 2015-03-25 | 公安部沈阳消防研究所 | Fire sign detection device and method |
| CN106290089A (en) * | 2015-05-12 | 2017-01-04 | 杜晨光 | A kind of high-precision miniaturization particulate matter sensors |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| AV01 | Patent right actively abandoned |
Effective date of abandoning: 20081022 |
|
| C25 | Abandonment of patent right or utility model to avoid double patenting |