CN113933228A - Particle counter with early warning function and working mode judgment method - Google Patents
Particle counter with early warning function and working mode judgment method Download PDFInfo
- Publication number
- CN113933228A CN113933228A CN202111112051.XA CN202111112051A CN113933228A CN 113933228 A CN113933228 A CN 113933228A CN 202111112051 A CN202111112051 A CN 202111112051A CN 113933228 A CN113933228 A CN 113933228A
- Authority
- CN
- China
- Prior art keywords
- gas
- concentration
- processor
- particle
- particle counter
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 239000002245 particle Substances 0.000 title claims abstract description 311
- 238000000034 method Methods 0.000 title claims abstract description 26
- 238000012545 processing Methods 0.000 claims abstract description 29
- 230000007246 mechanism Effects 0.000 claims abstract description 28
- 230000003287 optical effect Effects 0.000 claims abstract description 11
- 238000004364 calculation method Methods 0.000 claims abstract description 7
- 238000005259 measurement Methods 0.000 claims description 32
- 238000006243 chemical reaction Methods 0.000 claims description 3
- 238000012544 monitoring process Methods 0.000 claims description 2
- 230000008569 process Effects 0.000 abstract description 6
- 238000010586 diagram Methods 0.000 description 7
- 238000001914 filtration Methods 0.000 description 7
- 238000007493 shaping process Methods 0.000 description 5
- 230000009286 beneficial effect Effects 0.000 description 4
- 238000000149 argon plasma sintering Methods 0.000 description 3
- 238000009826 distribution Methods 0.000 description 3
- 239000000428 dust Substances 0.000 description 3
- 230000002159 abnormal effect Effects 0.000 description 2
- 238000004458 analytical method Methods 0.000 description 2
- 238000007689 inspection Methods 0.000 description 2
- 238000012806 monitoring device Methods 0.000 description 2
- 230000001105 regulatory effect Effects 0.000 description 2
- 241001270131 Agaricus moelleri Species 0.000 description 1
- 230000003321 amplification Effects 0.000 description 1
- 239000008280 blood Substances 0.000 description 1
- 210000004369 blood Anatomy 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 238000004140 cleaning Methods 0.000 description 1
- 238000010835 comparative analysis Methods 0.000 description 1
- 230000001276 controlling effect Effects 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 238000007599 discharging Methods 0.000 description 1
- 201000010099 disease Diseases 0.000 description 1
- 208000037265 diseases, disorders, signs and symptoms Diseases 0.000 description 1
- 239000003814 drug Substances 0.000 description 1
- 229940079593 drug Drugs 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 239000010419 fine particle Substances 0.000 description 1
- 238000012905 input function Methods 0.000 description 1
- 230000031700 light absorption Effects 0.000 description 1
- 238000003754 machining Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000003199 nucleic acid amplification method Methods 0.000 description 1
- 239000003973 paint Substances 0.000 description 1
- 229920003023 plastic Polymers 0.000 description 1
- 239000004033 plastic Substances 0.000 description 1
- 230000002265 prevention Effects 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 238000005070 sampling Methods 0.000 description 1
- 239000004065 semiconductor Substances 0.000 description 1
- 238000005507 spraying Methods 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N15/00—Investigating characteristics of particles; Investigating permeability, pore-volume, or surface-area of porous materials
- G01N15/10—Investigating individual particles
- G01N15/14—Electro-optical investigation, e.g. flow cytometers
- G01N15/1434—Electro-optical investigation, e.g. flow cytometers using an analyser being characterised by its optical arrangement
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N15/00—Investigating characteristics of particles; Investigating permeability, pore-volume, or surface-area of porous materials
- G01N15/02—Investigating particle size or size distribution
- G01N15/0205—Investigating particle size or size distribution by optical means, e.g. by light scattering, diffraction, holography or imaging
- G01N15/0211—Investigating a scatter or diffraction pattern
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N15/00—Investigating characteristics of particles; Investigating permeability, pore-volume, or surface-area of porous materials
- G01N15/06—Investigating concentration of particle suspensions
-
- G01N15/075—
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N15/00—Investigating characteristics of particles; Investigating permeability, pore-volume, or surface-area of porous materials
- G01N15/10—Investigating individual particles
- G01N15/14—Electro-optical investigation, e.g. flow cytometers
- G01N2015/1486—Counting the particles
Landscapes
- Chemical & Material Sciences (AREA)
- Dispersion Chemistry (AREA)
- Physics & Mathematics (AREA)
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Investigating Or Analysing Materials By Optical Means (AREA)
Abstract
The invention provides a particle counter, which comprises an optical path system and an air path system, wherein the air path system comprises an air inlet mechanism and an air outlet mechanism; the scattered light collecting system comprises a photoelectric detector, a signal processing circuit converts a photocurrent signal into a voltage pulse signal, a first processor processes the voltage pulse signal and then carries out particle concentration calculation, and a second processor processes the voltage pulse signal and then carries out particle counting statistics; the control system is used for receiving information of the first processor and/or the second processor and/or controlling the first processor and/or the second processor. Through set up inlet channel in the gas circuit system, first treater calculates the gas particle concentration that awaits measuring, judges whether particle counter has the pollution, lets in gas particle or clean gas to await measuring based on the judged result, reaches the purpose that prevents particle counter pollution, guarantees the counting accuracy. A working mode judging method is also provided, which can improve the accuracy of the particle counter.
Description
Technical Field
The invention relates to the technical field of particle counters, in particular to a particle counter with an early warning function and a working mode judging method.
Background
The particle counter is a special instrument for testing the particle size and the distribution of airborne dust particles, and is widely applied to authorities such as drug inspection departments, blood centers, epidemic prevention stations, disease control centers, quality supervision departments and the like in various provinces and cities, and production enterprises and scientific research departments such as electronic industries, pharmaceutical workshops, semiconductors, optical or precision machining, plastics, paint spraying, hospitals, environmental protection departments, inspection departments and the like.
A particle counter is an instrument that uses the principle of light scattering to count dust particles. Light scattering is related to factors such as particle size, wavelength of light, refractive index of the particles, and light absorption characteristics of the particles. However, there is a fundamental rule regarding the intensity of scattered light and particle size that the intensity of light scattered by a particle increases as the surface area of the particle increases. The dust-containing gas with a certain flow rate enables particles to emit scattered light through a beam of strong light, the scattered light is projected onto a photomultiplier through a condenser lens, the light pulse is changed into electric pulse, and the number of the particles is obtained through the pulse number. The particle diameter is obtained from the functional relationship between the intensity of the scattered light of the particles and the particle size. The basic principle of the light scattering particle counter is that the size of the fine particles can be estimated by measuring the intensity of the scattered light.
In order to obtain accurate particle count, ideally, the particle counter works to obtain particle count by collecting scattered light of particles passing through the photosensitive region one by one, and if the concentration of particles in the gas to be measured is high, the possibility that a plurality of particles enter the photosensitive region simultaneously or exist in the photosensitive region simultaneously is greatly improved, so that the overlapping loss or loss error of the particle counter is caused, and the measurement error of the particle counter is caused; in extreme cases, when the particles gushing into the gas path of the particle counter are too many, the cavity of the particle counter is even polluted.
Therefore, it is necessary to provide a particle counter capable of determining whether the concentration of particles in the measurement cavity of the particle counter exceeds the standard and having an early warning function.
Disclosure of Invention
The invention provides a particle counter with an early warning function, which can judge whether the concentration of particles in a measurement cavity exceeds the standard or not and can process the particles in time, so that the pollution of the particle counter is prevented, and the counting accuracy of the particle counter is ensured.
The invention also provides a method for judging the working mode of the particle counter, which can reduce the overlapping loss or loss error of the particle counter.
Other objects and advantages of the present invention will be further understood from the technical features disclosed in the present invention.
In order to achieve one or a part of or all of the above or other objects, a particle counter with an early warning function according to an aspect of the present invention includes: an optical path system including a light source; the gas path system comprises a gas inlet mechanism and a gas outlet mechanism, wherein the gas inlet mechanism comprises a gas inlet channel for introducing gas particles and/or clean gas to be detected; a scattered light collection system comprising a photodetector for receiving scattered light; the signal processing circuit is connected with the output end of the photoelectric detector and converts the collected photocurrent signals into voltage pulse signals; further comprising: the first processor and the second processor are respectively connected with the signal processing circuit, wherein the first processor performs particle concentration calculation after processing the voltage pulse signals, and the second processor performs particle counting statistics after processing the voltage pulse signals; and a control system for receiving information of the first processor and/or the second processor and/or controlling the first processor and/or the second processor.
The beneficial effects of this scheme lie in, calculate the gas particle concentration that awaits measuring through first treater, judge that the gas particle that awaits measuring in the particle counter exists concentration and surpasss preset standard to let in gas particle or clean gas to await measuring based on the judged result, reach and prevent that the particle counter concentration from surpassing the emergence that preset standard leads to the inaccurate condition of count, guarantee the purpose of particle counter's counting degree of accuracy.
The particle counter also comprises a signal acquisition circuit, wherein the signal acquisition circuit is connected with the output end of the signal processing circuit and is used for sampling the voltage pulse signal and converting the voltage pulse signal into a digital signal. The first processor and the second processor are connected with the signal processing circuit through the signal acquisition circuit. The signal acquisition circuit is an analog-to-digital conversion circuit. The technical scheme has the advantages that the continuous signals in the analog form are converted into the discrete signals in the digital form through the signal acquisition circuit, so that the signals are easier to store and process, and the processing of a processor is facilitated. The first processor can be directly connected with the signal processing circuit through the signal acquisition circuit, and the first processor can also be connected with the signal acquisition circuit through the second processor and then connected to the signal processing circuit.
The signal processing circuit includes an amplifying circuit for amplifying the photocurrent signal.
The signal processing circuit further comprises a filtering circuit for filtering the interference signal.
And the first processor counts and calculates the digital signals acquired by the signal acquisition circuit to obtain the concentration of the gas particles to be detected.
The second processor includes at least one comparator, and at least one count channel. Preferably, the number of comparators and the number of counting channels are the same. The comparator is used for comparing the voltage pulse signal of the gas particles to be detected with the preset threshold voltage of each particle with the particle size, and the counting channel counts the pulse signals meeting the threshold voltage standard after comparison and calculation to obtain the number of particles with the particle size corresponding to the threshold voltage.
To achieve one or a part of or all of the above or other objects, an embodiment of the present invention provides a method for determining an operation mode of a particle counter, including: step 1, receiving gas particles to be detected; step 2, detecting the concentration of the gas particles to be detected and obtaining the concentration data of the gas particles to be detected; and 3, comparing the concentration data of the gas particles to be detected with a preset early warning concentration, counting the gas particles to be detected by a particle counter and acquiring counting data based on the condition that the concentration data of the gas particles to be detected is lower than the preset early warning concentration, or taking early warning measures based on the condition that the concentration data of the gas particles to be detected is higher than the preset early warning concentration.
Wherein the step 1 comprises: the gas circuit system of the particle counter obtains the gas particles to be detected and transmits the gas particles to the scattered light collecting system, the photoelectric detector receives the scattered light of the gas particles to be detected, converts the scattered light into a photocurrent signal and transmits the photocurrent signal to the signal processing circuit, and the signal processing circuit converts the photocurrent signal into a voltage pulse signal. The step 2 comprises the following steps: and a first processor of the particle counter measures the concentration of the gas particles to be measured according to the voltage pulse signal and obtains the concentration data of the gas particles to be measured. The step 3 comprises the following steps: based on the comparison result of the gas particle concentration data to be detected and preset early warning concentration data, when the gas particle concentration to be detected is smaller than the preset early warning concentration, the particle counter continues to count particles; and when the concentration of the gas particles to be detected is not less than the preset early warning concentration, stopping inputting the gas particles to be detected into the gas inlet channel of the particle counter.
The technical scheme has the beneficial effects that the concentration data of the gas particles to be detected is compared with the preset value through presetting the early warning concentration, the particle counter is judged to be in a normal working state or the concentration in the cavity exceeds the preset concentration standard, so that the counter cannot count accurately or even the cavity is in a pollution state, corresponding measures can be taken according to the judgment result, the occurrence of inaccurate counting of the particle counter is avoided, and the accuracy of the particle counter is improved.
And the second processor of the particle counter counts and counts the particle number of the gas particles to be detected according to the voltage pulse signals in step 2 and/or step 3. When the concentration of the gas particles to be detected is less than the preset early warning concentration, the counting data of the second processor is brought into the data of normal particle counting work; and when the concentration of the gas particles to be detected is not less than the preset early warning concentration, the second processor stops particle counting work or continues counting work, and the obtained counting data is used as invalid data.
Further, the method for determining the operating mode of the particle counter further includes step 4: after the gas particles to be measured are stopped being input into the air inlet channel of the particle counter, the measurement cavity of the particle counter is cleaned by inputting clean gas into the air inlet channel of the air path system until the measurement cavity meets the preset standard measurement condition.
The gas path of the clean gas at least partially coincides with the gas path of the gas particles to be measured in the gas path of the gas inlet mechanism, and as an optional scheme, the clean gas and the gas particles to be measured share the gas inlet nozzle which is used for conveying the gas to the photosensitive area in the measurement cavity by the gas inlet mechanism and the gas outlet mechanism which is used for removing the gas in the measurement cavity.
Compared with the prior art, the invention has the beneficial effects that:
1. the utility model provides a particle counter with early warning function calculates the gas particle concentration that awaits measuring through first treater, judges whether the gas particle that awaits measuring exists concentration among the particle counter and surpasss preset standard to let in gas particle or clean gas that await measuring based on the judged result, reach and prevent that particle counter concentration from surpassing preset standard and leading to the emergence of the inaccurate condition of count, guarantee the purpose of particle counter's the count degree of accuracy.
2. According to the working mode judging method of the particle counter, the concentration data of the gas particles to be detected is compared with the preset value through presetting the early warning concentration, and whether the particle counter is in a normal working state or a pollution state is judged, so that corresponding measures can be taken according to the judgment result, the phenomenon that the particle counter counts inaccurately is avoided, and the accuracy of the particle counter is improved.
In order to make the aforementioned and other objects, features and advantages of the present invention comprehensible, preferred embodiments accompanied with figures are described in detail below.
Drawings
In order to more clearly illustrate the technical solutions in the specific embodiments of the present invention, the drawings needed to be used in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings described below are only some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained according to these drawings without inventive efforts.
Fig. 1 is a block diagram of a particle counter with an early warning function according to a first embodiment of the present invention.
Fig. 2 is a block diagram of an air path system of a particle counter according to a first embodiment of the present invention.
Fig. 3 is a block diagram of an air path system of a particle counter according to a second embodiment of the present invention.
Fig. 4 is a block diagram of a particle counter with an early warning function according to a third embodiment of the present invention.
Fig. 5 is a flowchart illustrating a method for determining a working mode of a particle counter according to a fourth embodiment of the present invention.
Fig. 6 is a schematic flowchart of a method for determining a working mode of a particle counter according to a fifth embodiment of the present invention.
Detailed Description
The foregoing and other technical and scientific aspects, features and advantages of the present invention will be apparent from the following detailed description of a preferred embodiment, which is to be read in connection with the accompanying drawings. Directional terms as set forth in the following examples, for example: up, down, left, right, front or rear, etc., are referred to only in the direction of the attached drawings. Accordingly, the directional terminology is used for purposes of illustration and is in no way limiting.
Fig. 1 and fig. 2 are block diagrams of a particle counter with an early warning function and a gas circuit system thereof according to a first embodiment of the present invention. Referring to fig. 1 and 2 in combination, the particle counter of the present embodiment includes an optical path system, a scattered light collecting system, a signal processing circuit 5, a signal acquisition circuit 6, a first processor 7, a second processor 8, and a control system 9.
The optical path system of the present embodiment includes a light source 11, an optical shaping mechanism 12, and an optical trap 13. The light source 11 may be a laser light source for providing a laser beam, and the laser beam is shaped by the optical shaping mechanism 12 and then output to form a light path. The optical shaping mechanism 12 can be one or a combination of a non-spherical lens, a cylindrical mirror, a diaphragm and the like, and aims to shape the laser beam, eliminate the side lobe of the beam, shape the laser beam with Gaussian distribution into a flat-top beam with uniform energy distribution, and improve the performance of a light source for subsequent utilization; the light trap 13 disposed behind the photosensitive region in the light beam propagation direction absorbs the light beam.
The air path system includes an air inlet mechanism and an air outlet mechanism 32. The air inlet mechanism further includes a gas particle inlet passage 311, a gas particle inlet switch 312, a clean gas inlet passage 313, and a clean gas inlet switch 314. The gas particles to be measured are gas containing the particles to be measured, the gas inlet switch 312 of the gas particles to be measured is opened, the gas particles to be measured enter the gas inlet passage 315 and enter the photosensitive area 4 through the gas inlet nozzle 316, and are output through the gas outlet mechanism 32, and the gas path formed by the gas output by the gas inlet passage 315 and the light path output by shaping of the optical shaping mechanism 12 form the photosensitive area 4. The clean gas inlet switch 314 is used for switching the clean gas inlet passage 313 to realize the input of clean gas into the inlet passage 315. The gas particle inlet switch 312 to be measured and the clean gas inlet switch 314 are not turned on at the same time, and of course, in other embodiments, the two switches 312 and 314 may be turned on all the time, and only the gas particle to be measured and the clean gas need not be simultaneously introduced.
The opening and closing of the gas particle inlet switch 312 to be detected and the clean gas inlet switch 314 can be controlled by manually operating the switches to control the input of the gas particles to be detected or the clean gas; or, the gas particle inlet switch 312 to be measured and the clean gas inlet switch 314 are connected to the control system through signals, and the control system controls the opening and closing of the gas particle inlet switch 312 to be measured and the clean gas inlet switch 314 to control the input of the gas particles to be measured or the clean gas.
Further, other embodiments of the air inlet mechanism optionally include an air inlet flow regulating mechanism such as a flow regulating valve that is signally connected to a control system that can regulate the air inlet flow rate based on predetermined conditions.
The scattered light collection system includes a photodetector 21 and a light reflector 22. The gas particles to be measured are scattered in the photosensitive area 4, and the scattered light is received by the photoelectric detector 21 and converted into a photocurrent signal directly or after being reflected by the light reflecting mirror 22.
The signal processing circuit 5 is connected to the output terminal of the photodetector 21, and converts the photocurrent signal into a voltage pulse signal. Specifically, in this embodiment, the signal processing circuit 5 includes an amplifying circuit and a filtering circuit, and the photocurrent signal is amplified by the amplifying circuit and is converted into a voltage pulse signal after the interference signal is filtered by the filtering circuit. The sequence of amplification and filtering is not particularly limited in the present invention.
The signal acquisition circuit 6 is connected to the output terminal of the signal processing circuit 5, and samples and converts the voltage pulse signal into a digital voltage pulse signal, and the signal acquisition circuit 6 may be, for example, an analog-to-digital ADC conversion circuit.
A first processor 7 and a second processor 8 are connected to the signal acquisition circuit 6. The first processor 7 is a concentration monitoring device, and is configured to receive the digital voltage pulse signal, perform statistics and calculation, and obtain the concentration of the gas particles to be measured. Optionally, the first processor is used for accumulating the voltage amplitude values acquired by the signal acquisition circuit and dividing the voltage amplitude values by the acquisition time to obtain an average value, and then the average value is calculated by combining preset particle size and density parameters to obtain the concentration data of the signal acquisition circuit in real time.
The second processor 8 is a counting monitoring device, and is configured to receive the digital voltage pulse signal and process the digital voltage pulse signal to obtain counting data of the number of the gas particles to be detected. In this embodiment, the second processor 8 may include, for example, a plurality of comparators and a plurality of counting channels, the number of the comparators and the number of the counting channels are preferably kept consistent, and the plurality of comparators compare the voltage amplitude of the digital voltage pulse signal of the gas particles to be detected with the threshold voltage, so that the counting channel with the maximum threshold voltage reaches counts the particles reaching the standard of the threshold voltage, obtain the number of corresponding particles with different particle sizes, and implement the function of counting the particles with multiple particle sizes. In other embodiments, the second processor 8 may integrate the voltage amplitude of the to-be-measured particle voltage pulse signal with the time amplitude to obtain an integrated value of the particle, and compare the integrated value of the to-be-measured particle with the integrated values of the standard particles of each particle size to obtain the number of corresponding particles of different particle sizes, thereby implementing the function of counting the particles of multiple particle sizes.
The first processor 7 transmits the concentration of the gas particles to be measured and the second processor 8 transmits the counting data to the control system 9. The control system 9 compares the concentration of the gas particles to be detected with the pre-set early warning concentration parameter in the control system for analysis, and when the particle concentration data is smaller than the early warning concentration, the control system 9 controls the second processor 8 to continue counting the particles; when the particle concentration data is greater than or equal to the early warning concentration, the control system 9 controls the second processor 8 to stop counting particles; or marking the counting data of the second processor 8 based on the comparative analysis result, when the concentration of the gas particles to be detected is greater than or equal to the preset early warning concentration parameter, marking the counting data of the second processor 8 as invalid data, and when the concentration of the gas particles to be detected is less than the preset early warning concentration parameter, marking the counting data of the second processor 8 as valid data or not.
In addition, when the gas particle concentration that the contrast analysis goes out that awaits measuring exceeds predetermined early warning concentration parameter, control system 9 can also control and stop the input of the gas particle that awaits measuring, change by clean gas suction nozzle to the input clean gas in the measurement chamber of particle counter, first processor 7 continuously monitors the concentration data in the particle counter measurement chamber, accord with preset clean standard in the measurement chamber until, and then control system 9 control clean gas stops the input, continues the input of the gas particle that awaits measuring and carries out concentration detection and particle count work.
The beneficial effects of this technical scheme lie in, through set up two inlet channels in particle counter's gas circuit system, calculate the gaseous particle concentration that awaits measuring and input control system 9 and compare with predetermined early warning concentration in the control system 9 through first treater 7, judge whether there is the pollution in the particle counter, and open inlet mechanism's different inlet channels based on the judged result, reach and prevent that particle counter from polluting the emergence that leads to counting the inaccurate condition, guarantee particle counter's the purpose of the count degree of accuracy.
Fig. 3 is a block diagram of an air path system of a particle counter according to a second embodiment of the present invention. The difference from the first embodiment is that the air inlet mechanism does not include an air inlet channel for gas particles to be tested, an air inlet switch for gas particles to be tested, a clean air inlet channel and a clean air inlet switch which are independently switched, but a gas particle filter 317 is connected to the air inlet channel 315, when the gas particles to be tested enter the air inlet channel 315 through the gas particle filter 317, the gas particle filter 317 in an operating state can filter particles in the gas particles to obtain clean air, and the clean air is delivered to the air inlet channel 315, that is, when the gas particle filter 317 is connected to the air inlet channel and particle filtering operation is started, the clean air is delivered to the air inlet channel 315, and when the gas particle filter 317 is connected to the air inlet channel but particle filtering operation is not started, the gas particles to be tested are delivered to the air inlet channel 315. In other embodiments, the gas particle filter 317 is detachably connected to the gas passage 315, when the gas particles to be measured are input, the gas particle filter 317 is disconnected from the gas passage 315, and when the clean gas is input, the gas particle filter 317 is connected to the gas passage 315 and works, so that the input function of the gas particles to be measured and the clean gas is realized, and the structure is simple.
Fig. 4 is a block diagram of a particle counter with an early warning function according to a third embodiment of the present invention. The difference from the first embodiment is that the first processor 7 is connected to the output end of the second processor 8, and obtains concentration data in real time for the number of the gas particles to be measured counted in the second processor 8 and the particle size statistics in combination with the density.
In other embodiments, the second embodiment may be combined with the third embodiment to obtain a particle counter with an early warning function.
Fig. 5 is a flowchart illustrating a method for determining a working mode of a particle counter according to a fourth embodiment of the present invention. The operation mode determination method operates based on the particle counters in the first to third embodiments.
Referring to fig. 5, the method for determining the operating mode of the particle counter of the present embodiment includes: step 1, receiving gas particles to be detected. Specifically, gas particles to be detected are input into an air inlet channel of an air channel system of the particle counter, an air flow output by an air inlet nozzle of the air inlet channel and a light path form a photosensitive area, the gas particles to be detected are scattered in the photosensitive area, scattered light is received by a photoelectric detector in a scattered light collecting system and is converted into a photocurrent signal, and the photocurrent signal is converted into a voltage pulse signal through a signal processing circuit. Furthermore, the voltage pulse signals can be converted into more easily processed digital voltage pulse signals through the signal acquisition circuit.
And 2, monitoring the concentration of the gas particles to be detected and obtaining the concentration data of the gas particles to be detected. The method specifically comprises the following steps: and the first processor measures the concentration of the gas particles to be measured according to the voltage pulse signal or the digital voltage pulse signal and obtains the concentration data of the gas particles to be measured. At this time, the second processor may directly start counting the gas particles to be measured according to the voltage pulse signal or the digital voltage pulse signal.
And 3, comparing the concentration data of the gas particles to be detected with a preset early warning concentration, counting the gas particles to be detected by a particle counter and acquiring counting data based on the condition that the concentration data of the gas particles to be detected is lower than the preset early warning concentration, or taking early warning measures based on the condition that the concentration data of the gas particles to be detected is higher than the preset early warning concentration.
Wherein, step 3 specifically includes: and when the concentration of the gas particles to be detected is less than the preset early warning concentration, the second processor continues to count the gas particles to be detected, and the counting data of the second processor is brought into the data of normal particle counting work, namely effective data. When the concentration of the gas particles to be detected is not less than the preset early warning concentration, the gas particles to be detected are stopped being input into the gas inlet channel of the particle counter, at the moment, the control system can control the second processor to continuously count or stop counting, but the counting data is included in the data stopping normal particle counting, namely invalid data.
And 4, after the gas particles to be measured are stopped being input into the air inlet channel of the particle counter, cleaning the measurement cavity of the particle counter by inputting clean gas into the air inlet channel until the measurement cavity of the particle counter meets the preset standard measurement condition, namely the first processor still works at the moment until the concentration data in the measurement cavity is measured to meet the reference value of the clean gas. In addition, the second processor can work at the same time to measure technical data in the measurement cavity until the standard measurement conditions are met. The particle counter may be restarted to begin the operation of loop step 1-4.
Fig. 6 is a schematic flowchart of a method for determining an operating mode of a particle counter according to a fifth embodiment of the present invention. Referring to fig. 6, the difference between the fourth embodiment and the fourth embodiment is that, in step 2, the second processor is not started to perform the particle counting on the gas particles to be measured, but it is determined whether to start the second processor to perform the particle counting based on the comparison result between the concentration of the gas particles to be measured and the preset warning concentration in step 3.
The sixth embodiment of the invention is further optimized on the basis of the fourth embodiment and the fifth embodiment. Specifically, the preset early warning concentration in this embodiment includes a plurality of early warning concentration values, a gas flow or flow rate control device is disposed in the air intake mechanism, and the control system controls the gas flow or flow rate control device in the air intake mechanism to adjustably control the air intake flow or flow rate of the air intake mechanism. Illustratively, a first warning concentration, a second warning concentration, an X-n warning concentration …, an X warning concentration …, etc., where n is less than X and X is greater than 1, the warning concentrations may be determined according to a reference particle concentration of a space environment where the particle counter is used, a gradient concentration warning parameter of a preset unit volume of particle concentration, and a warning concentration parameter of a pollution of a measurement cavity of the particle counter, where the gradient concentration warning parameter of the preset unit volume of particle concentration includes a warning concentration that is preset to generate a measurement error, and a pilot warning concentration that is set in a ratio of the warning concentration that is preset to generate the measurement error, that is, the ratio is multiplied by a warning concentration value that is preset to generate the measurement error, and the ratio setting is less than 1, for example, 0.5, 0.6, 0.7, 0.8, 0.9, etc., and the ratio value is preset according to actual conditions. When the concentration of the gas particles to be measured is larger than or equal to the polluted early warning concentration parameter of the particle counter measuring cavity, clean gas is introduced to clean the measuring cavity; when the concentration of the gas particles to be measured reaches the X-n early warning concentration of the proportional value of the early warning concentration value generating the measurement error in a preset manner but is smaller than the early warning concentration value generating the measurement error in a preset manner, the first processor and the second processor work normally, the control system controls the air inlet mechanism to reduce the air inlet flow speed or flow of the gas particles to be measured in the air inlet channel, and the measurement error is reduced by reducing the inlet amount of the gas particles to be measured in unit time; when the concentration of the pre-set gas particles generating the measurement error is less than the concentration of the pre-set gas particles to be measured and less than the concentration of the pre-set gas particles to be measured, the particle counter measures the polluted pre-set concentration parameter of the measurement cavity, the clean gas is not introduced to clean the measurement cavity, and the accuracy of the data of the particle counter is improved by calculating and removing the data when the concentration of the pre-set gas particles generating the measurement error is less than or equal to the concentration of the pre-set gas particles to be measured through the control system of the particle counter. Specifically, when the preset early warning concentration generating the measurement error is less than or equal to the concentration of the gas particles to be measured, the particle counter can stop the counting operation of the second processor, although the gas circuit system still introduces the gas particles to be measured at the moment, the control system removes the relevant data segment (such as the duration of the period, the volume of the gas entering and the like) of the particle counter stopping the counting operation of the number of the particles during the counting operation to calculate, so as to realize the effective counting of the particle counter; or, the counting work of the second processor is still carried out, but the counting number of the segment is marked as abnormal data, and the abnormal data is cut off by the normal particle counting process together with other related calculation parameters of the segment, so that the counting of the particle number is not involved, and the overlapping loss or the loss error of the particle counter can be reduced; or, the control system can adjust the volume of the gas particles to be detected, for example, reduce the gas inlet flow rate of the gas particles to be detected, reduce the pressure of the gas outlet mechanism discharging the gas particles to be detected with the concentration exceeding the pre-warning concentration, and continuously monitor the concentration and count the number of the gas particles to be detected.
The above description is only a preferred embodiment of the present invention, and not intended to limit the scope of the invention, which is defined by the claims and the description of the invention, and all simple equivalent changes and modifications made therein are also within the scope of the invention. Moreover, it is not necessary for any embodiment or claim of the invention to address all of the objects, advantages, or features disclosed herein. In addition, the abstract and the title of the invention are provided for assisting the retrieval of patent documents and are not intended to limit the scope of the invention. Furthermore, the terms "first", "second", and the like in the description or the claims are used only for naming elements (elements) or distinguishing different embodiments or ranges, and are not used for limiting the upper limit or the lower limit on the number of elements.
Claims (10)
1. A particle counter with an early warning function, comprising:
an optical path system including a light source;
the gas path system comprises a gas inlet mechanism and a gas outlet mechanism, wherein the gas inlet mechanism comprises a gas inlet channel for introducing gas particles and/or clean gas to be detected;
a scattered light collection system comprising a photodetector for receiving scattered light;
the signal processing circuit is connected with the output end of the photoelectric detector and converts the collected photocurrent signals into voltage pulse signals;
the first processor and the second processor are respectively connected with the signal processing circuit; the first processor performs particle concentration calculation after processing the voltage pulse signal, and the second processor performs particle counting statistics after processing the voltage pulse signal;
and the control system is used for receiving information of the first processor and/or the second processor and/or controlling the first processor and/or the second processor.
2. The particle counter with the early warning function according to claim 1, further comprising a signal acquisition circuit, wherein the signal acquisition circuit is connected to an output end of the signal processing circuit, and is configured to sample the voltage pulse signal and convert the voltage pulse signal into a digital signal;
preferably, the first processor and the second processor are connected with the signal processing circuit through the signal acquisition circuit;
preferably, the signal acquisition circuit is an analog-to-digital conversion circuit.
3. The particle counter with early warning function according to claim 1, wherein the signal processing circuit comprises an amplifying circuit for amplifying the photocurrent signal;
preferably, the signal processing circuit further comprises a filter circuit.
4. The particle counter with the early warning function according to claim 2, wherein the first processor performs statistics and calculation on the digital signals acquired by the signal acquisition circuit to obtain the concentration of the gas particles to be measured.
5. The particle counter with early warning function of claim 1, wherein the second processor comprises at least one comparator, and at least one counting channel; preferably; the number of comparators is the same as the number of counting channels.
6. The method for determining an operation mode of a particle counter according to any one of claims 1 to 5, comprising:
step 1, receiving gas particles to be detected;
step 2, monitoring the concentration of the gas particles to be detected and obtaining the concentration data of the gas particles to be detected;
and 3, comparing the concentration data of the gas particles to be detected with a preset early warning concentration, counting the gas particles to be detected by a particle counter and acquiring counting data based on the condition that the concentration data of the gas particles to be detected is lower than the preset early warning concentration, or taking early warning measures based on the condition that the concentration data of the gas particles to be detected is higher than the preset early warning concentration.
7. The method for determining an operation mode of a particle counter according to claim 6,
the step 1 comprises the following steps: the gas circuit system of the particle counter obtains the gas particles to be detected and transmits the gas particles to the scattered light collecting system, the photoelectric detector receives the scattered light of the gas particles to be detected, converts the scattered light into a photocurrent signal and transmits the photocurrent signal to the signal processing circuit, and the signal processing circuit converts the photocurrent signal into a voltage pulse signal;
the step 2 comprises the following steps: a first processor of the particle counter measures the concentration of the gas particles to be measured according to the voltage pulse signal and obtains the concentration data of the gas particles to be measured;
the step 3 comprises the following steps: based on the comparison result of the gas particle concentration data to be detected and preset early warning concentration data, when the gas particle concentration to be detected is smaller than the preset early warning concentration, the particle counter continues to count particles; and when the concentration of the gas particles to be detected is not less than the preset early warning concentration, stopping inputting the gas particles to be detected into the gas inlet channel of the particle counter.
8. The method for determining an operation mode of a particle counter according to claim 7, wherein the second processor counts the number of particles in the gas particles to be measured according to the voltage pulse signal in step 2 and/or step 3.
9. The method for determining the operating mode of the particle counter according to claim 8, wherein when the concentration of the gas particles to be measured is less than the preset warning concentration, the count data of the second processor is included in the data of the normal particle count operation; and when the concentration of the gas particles to be detected is not less than the preset early warning concentration, stopping the particle counting work by the second processor or continuing the counting work, and taking the obtained counting data as invalid data.
10. The method for determining an operation mode of a particle counter according to claim 7, further comprising step 4: after the gas particles to be measured are stopped being input into the air inlet channel of the particle counter, the measurement cavity of the particle counter is cleaned by inputting clean gas into the air inlet channel of the air path system until the measurement cavity meets the preset standard measurement condition.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111112051.XA CN113933228A (en) | 2021-09-18 | 2021-09-18 | Particle counter with early warning function and working mode judgment method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111112051.XA CN113933228A (en) | 2021-09-18 | 2021-09-18 | Particle counter with early warning function and working mode judgment method |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN113933228A true CN113933228A (en) | 2022-01-14 |
Family
ID=79276290
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202111112051.XA Pending CN113933228A (en) | 2021-09-18 | 2021-09-18 | Particle counter with early warning function and working mode judgment method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113933228A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114486688A (en) * | 2022-01-28 | 2022-05-13 | 苏州苏信环境科技有限公司 | Particle counter metering method, device, equipment and storage medium |
| CN114544441A (en) * | 2022-02-28 | 2022-05-27 | 苏州苏信环境科技有限公司 | Self-checking method, system, device and medium of particle counter |
| CN117169092A (en) * | 2023-09-01 | 2023-12-05 | 深圳市宏大联合实业有限公司 | Photoelectric sensor based on small-flow dust particle counter and counting method thereof |
Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104266947A (en) * | 2014-09-15 | 2015-01-07 | 中国科学院上海光学精密机械研究所 | Aerosol particle concentration sensor and detection method thereof |
| CN104359815A (en) * | 2014-11-06 | 2015-02-18 | 北京中科诚毅科技发展有限公司 | Particulate matter mass concentration detector with self-purification system |
| CN205958420U (en) * | 2016-08-04 | 2017-02-15 | 安徽蓝盾光电子股份有限公司 | Light scattering particulate matter concentration detection device |
| CN206479435U (en) * | 2016-12-09 | 2017-09-08 | 浙江苏净净化设备有限公司 | A kind of laser dust particle counter |
| CN207396270U (en) * | 2017-10-20 | 2018-05-22 | 成都上甲光电科技有限公司 | For detecting the alarm of indoor clean level |
| CN207408276U (en) * | 2017-10-16 | 2018-05-25 | 肖雯丹 | A kind of air concentration of suspended particles measuring device of high-precision wholegrain footpath covering |
| CN110095392A (en) * | 2019-05-07 | 2019-08-06 | 河海大学常州校区 | A kind of dust detection method based on photoelectric sensor, apparatus and system |
| CN110296919A (en) * | 2019-07-30 | 2019-10-01 | 常熟市鼎睿智能测控有限公司 | A kind of suspended particulate matter concentration monitoring device based near forward scattering light detection |
| CN110411929A (en) * | 2019-08-27 | 2019-11-05 | 广州昊致电气自动化有限公司 | Monitor for insulation oveheat of generater and detection method based on laser light scattering principle |
| CN212031239U (en) * | 2019-11-18 | 2020-11-27 | 深圳市源建传感科技有限公司 | Sensor device of PM2.5 laser dust |
-
2021
- 2021-09-18 CN CN202111112051.XA patent/CN113933228A/en active Pending
Patent Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104266947A (en) * | 2014-09-15 | 2015-01-07 | 中国科学院上海光学精密机械研究所 | Aerosol particle concentration sensor and detection method thereof |
| CN104359815A (en) * | 2014-11-06 | 2015-02-18 | 北京中科诚毅科技发展有限公司 | Particulate matter mass concentration detector with self-purification system |
| CN205958420U (en) * | 2016-08-04 | 2017-02-15 | 安徽蓝盾光电子股份有限公司 | Light scattering particulate matter concentration detection device |
| CN206479435U (en) * | 2016-12-09 | 2017-09-08 | 浙江苏净净化设备有限公司 | A kind of laser dust particle counter |
| CN207408276U (en) * | 2017-10-16 | 2018-05-25 | 肖雯丹 | A kind of air concentration of suspended particles measuring device of high-precision wholegrain footpath covering |
| CN207396270U (en) * | 2017-10-20 | 2018-05-22 | 成都上甲光电科技有限公司 | For detecting the alarm of indoor clean level |
| CN110095392A (en) * | 2019-05-07 | 2019-08-06 | 河海大学常州校区 | A kind of dust detection method based on photoelectric sensor, apparatus and system |
| CN110296919A (en) * | 2019-07-30 | 2019-10-01 | 常熟市鼎睿智能测控有限公司 | A kind of suspended particulate matter concentration monitoring device based near forward scattering light detection |
| CN110411929A (en) * | 2019-08-27 | 2019-11-05 | 广州昊致电气自动化有限公司 | Monitor for insulation oveheat of generater and detection method based on laser light scattering principle |
| CN212031239U (en) * | 2019-11-18 | 2020-11-27 | 深圳市源建传感科技有限公司 | Sensor device of PM2.5 laser dust |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114486688A (en) * | 2022-01-28 | 2022-05-13 | 苏州苏信环境科技有限公司 | Particle counter metering method, device, equipment and storage medium |
| CN114544441A (en) * | 2022-02-28 | 2022-05-27 | 苏州苏信环境科技有限公司 | Self-checking method, system, device and medium of particle counter |
| CN117169092A (en) * | 2023-09-01 | 2023-12-05 | 深圳市宏大联合实业有限公司 | Photoelectric sensor based on small-flow dust particle counter and counting method thereof |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN113933228A (en) | Particle counter with early warning function and working mode judgment method | |
| US7932490B2 (en) | Size segregated aerosol mass concentration measurement device | |
| US8534116B2 (en) | Size segregated aerosol mass concentration measurement with inlet conditioners and multiple detectors | |
| US5943130A (en) | In situ sensor for near wafer particle monitoring in semiconductor device manufacturing equipment | |
| EP2741843B1 (en) | System and method for converting optical diameters of aerosol particles to mobility and aerodynamic diameters | |
| EP3730924B1 (en) | Flow device and associated method and system | |
| CN204422376U (en) | A kind of novel low-concentration flue gas detection system of particles | |
| US20080278725A1 (en) | Compact, low cost particle sensor | |
| US8717550B2 (en) | Method and device for detecting biological material | |
| WO2020047457A1 (en) | Fluid refractive index optimizing particle counter | |
| US20110310386A1 (en) | Method and system for analysing solid particles in a medium | |
| CN205826470U (en) | A kind of PM2.5 sensor | |
| WO2019147590A1 (en) | Bioaerosol particle detector | |
| KR102073483B1 (en) | Apparatus and method for measuring fine particulate matter | |
| CN115389384A (en) | Particle concentration detection system and method based on forward particle counter coupled lateral photometer | |
| CN210665421U (en) | Laser scattering particulate matter concentration analyzer | |
| CN102323193A (en) | Measurement method for air particle distribution through laser light scattering method, and apparatus thereof | |
| CN201788149U (en) | Light scattering type particulate matter on-line monitor with humidity correcting function | |
| CN112378813B (en) | Device and method for measuring density of atmospheric particulate matter | |
| WO1994003792A1 (en) | Aerosol discriminator | |
| US11789166B2 (en) | Pulse counting coincidence correction based on count rate and measured live time | |
| JPH0365636A (en) | Air pollution level detecting apparatus | |
| CN217931281U (en) | Continuous detection device for concentration of individual respiratory dust | |
| Haldhani | Particle number density distribution and its time history for an automotive air filter | |
| Kuhn | An instrument for monitoring number and mass of ambient particles in coarse, fine and ultrafine size ranges |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |