CN215866269U - Standard particle generating device - Google Patents
Standard particle generating device Download PDFInfo
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- CN215866269U CN215866269U CN202121900276.7U CN202121900276U CN215866269U CN 215866269 U CN215866269 U CN 215866269U CN 202121900276 U CN202121900276 U CN 202121900276U CN 215866269 U CN215866269 U CN 215866269U
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Abstract
The utility model discloses a standard particle generating device, which comprises at least two particle output systems, wherein any one particle output system comprises: the one end of hybrid tube is equipped with at least one first import and second import, the other end of hybrid tube is equipped with two at least exports. At least one atomizing unit, arbitrary one atomizing unit with its correspond first inlet intercommunication. The fan, the fan with the second import intercommunication of hybrid tube to input gas in the hybrid tube, make gas with fog granule mixing becomes aerosol in the hybrid tube, and then follow the export output of hybrid tube. The standard particle generating device greatly improves the testing efficiency and has higher use value.
Description
Technical Field
The utility model relates to a standard particle generating device.
Background
A dust particle counter is an instrument used to measure the number and particle size distribution of dust particles in a single volume in a clean environment. The accuracy of the dust particle counter needs to be tested before the dust particle counter leaves a factory, and mainly the accuracy of the dust particle counter in a dust particle number test and a particle size distribution test is tested.
The standard particle generating device is a detecting device for a dust particle counter. The standard particle generating device can output dust particles with preset sizes. During testing, the standard product of the dust particle counter and the product to be tested of the dust particle counter are connected with the standard particle generating device, and whether the product to be tested can reach the standard or not is judged according to the difference (namely, indicating value error) of the testing result between the standard product of the dust particle counter and the product to be tested of the dust particle counter. And the measurement of the indication error of the dust particle counter comprises the measurement of the particle size distribution of the dust particles and the measurement of the number of the dust particles.
For the particle size distribution measurement, when the standard particle generating device outputs particles with specific particle sizes, the standard product of the dust particle counter and the to-be-tested product of the dust particle counter respectively display the distribution conditions of the tested dust particles, and the method specifically comprises the following steps: the particle distribution quantity with the particle diameter of more than or equal to 0.3 mu m, the particle distribution quantity with the particle diameter of more than or equal to 0.5 mu m, the particle distribution quantity with the particle diameter of more than or equal to 1.0 mu m, the particle distribution quantity with the particle diameter of more than or equal to 3.0 mu m, the particle distribution quantity with the particle diameter of more than or equal to 5.0 mu m and the particle distribution quantity with the particle diameter of more than or equal to 10.0 mu m. The particles output by the standard particle generating device at each time need to be excluded from the point values (0.3 μm, 0.5 μm, 1.0 μm, 3.0 μm and 5.0 μm) to achieve the testing effect.
However, in the process of testing the number of dust particles, the particles output each time by the standard particle generating device are related to the point value. For example, the standard particle generator outputs 0.5 μm dust particles, and the standard dust particle counter and the DUT dust particle counter respectively display the number of 0.5 μm dust particles tested.
Traditional standard particle generating device, it only has single particle output system, can only export the particle of a kind of particle diameter at every turn, consequently, the particle size distribution of dust particle measures and the test of dust particle number can not use same standard particle generating device, causes the efficiency of software testing from this to be lower, influences the production progress.
In view of the above, there is a need for an improvement of the existing standard particle generating apparatus.
SUMMERY OF THE UTILITY MODEL
In order to overcome the defects in the prior art, the utility model provides a standard particle generating device, which greatly improves the testing efficiency and has higher use value.
The utility model discloses a standard particle generating device, which comprises at least two particle output systems, wherein any one particle output system comprises:
the mixing device comprises a mixing pipe, a first inlet, a second inlet, a first outlet and a second outlet, wherein one end of the mixing pipe is provided with at least one first inlet and one second inlet, and the other end of the mixing pipe is provided with at least two outlets;
at least one atomizing unit, wherein any one atomizing unit is communicated with the corresponding first inlet so as to input atomized particles into the mixing pipe, and the atomized particles contain dust particles with preset sizes; and
the fan, the fan with the second import intercommunication of hybrid tube to input gas in the hybrid tube, make gas with fog granule mixing becomes aerosol in the hybrid tube, and then follow the export output of hybrid tube.
Preferably, any one be equipped with shunt tubes and at least one speed reduction disc in the hybrid tube, any one the speed reduction disc perpendicular to the axis direction setting of hybrid tube, any one speed reduction disc with the inner wall of hybrid tube is connected, and any one a plurality of perforating holes have been seted up on the speed reduction disc, the air inlet of shunt tubes with the first import and the second import of hybrid tube all communicate in order to receive gas and vaporific granule, one of them is located to the gas outlet of shunt tubes the speed reduction disc is dorsad the one end of hybrid tube export.
Preferably, any one of the atomizing units includes a nozzle, a container, and a connection pipe, the connection pipe communicates with the first opening of the nozzle to input compressed air into the nozzle, the container communicates with the second opening of the nozzle to input a liquid containing dust particles of a predetermined size into the nozzle, so that the liquid is dispersed into mist-like particles by the compressed air and is output from the third opening of the nozzle, and the third opening of the nozzle communicates with the first inlet of the mixing pipe corresponding thereto.
Further preferably, the standard particle generating device comprises an air compressor, and one end of any one of the connecting pipes, which is far away from the nozzle, is communicated with the air compressor.
Still further preferably, a first regulating valve is provided between any one of the connecting pipes and the air compressor to control the flow rate of the compressed air.
Further preferably, at least one first filter is provided between any one of the connection pipes and the corresponding nozzle.
Preferably, a second regulating valve and a second filter are sequentially arranged between any one of the fans and the corresponding mixing pipe.
The utility model has the following beneficial effects:
the standard particle generating device is provided with at least two outlets through the mixing pipe, so that the two outlets of the mixing pipe can be respectively connected with the standard product of the dust particle counter and the product to be tested of the dust particle counter, the standard product and the product to be tested can obtain the aerosol output from the mixing pipe under the same test condition, and the test can be further carried out, so that the test accuracy of the product to be tested can be improved.
The standard particle generating device comprises at least two particle output systems, wherein any one particle output system can output dust particles meeting the requirement of a particle size distribution test and can output dust particles meeting the requirement of a dust particle number test, so that the two particle output systems can simultaneously perform the particle size distribution test items or the dust particle number test items, and the two particle output systems can also simultaneously perform different test items, namely one particle output system performs the particle size distribution test and the other particle output system performs the dust particle number test, therefore, the test efficiency is greatly improved, and the use value of the standard particle generating device is higher. And when one particle output system fails, the other particle output system can still be normally used, so that the production progress can be ensured to a certain extent.
In order to make the aforementioned and other objects, features and advantages of the utility model comprehensible, preferred embodiments accompanied with figures are described in detail below.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.
FIG. 1 is a schematic diagram of a standard particle generating apparatus according to an embodiment of the present invention;
FIG. 2 is a schematic diagram of a standard particle generating device in an embodiment of the utility model;
FIG. 3 is a cross-sectional view of a mixing tube having a first inlet in an embodiment of the present invention;
FIG. 4 is a partial cross-sectional view of a mixing tube having a first inlet in an embodiment of the present invention, primarily to show the configuration of the shunt tube and the speed reduction disk;
reference numerals of the above figures: 1-a mixing tube; 2-a fan; 3-a nozzle; 4-a container; 5-connecting pipe; 6-first regulating valve; 7-a first filter; 8-an air compressor; 9-total filter; 10-a second regulating valve; 11-a second filter; 12-a third filter; 101-a first inlet; 102-a second inlet; 103-an outlet; 104-a shunt tube; 105-a reduction disc; 106-adjusting disk; 1041-outlet.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
The utility model relates to a standard particle generating device, which is a indicating error detecting device for a dust particle counter, wherein the testing of the indicating error of the dust particle counter comprises the following steps: particle size distribution test and number of dust particles test.
The standard particle generating device comprises at least two particle output systems, wherein any one particle output system comprises:
the mixing device comprises a mixing pipe 1, wherein one end of the mixing pipe 1 is provided with at least one first inlet 101 and one second inlet 102, and the other end of the mixing pipe 1 is provided with at least two outlets 103;
at least one atomizing unit, wherein any one atomizing unit is communicated with the corresponding first inlet 101 so as to input atomized particles into the mixing pipe 1, and the atomized particles contain dust particles with preset sizes; and
and the fan 2 is communicated with the second inlet 102 of the mixing pipe 1 so as to input gas into the mixing pipe 1, so that the gas and the mist-shaped particles in the mixing pipe 1 are mixed into aerosol, and the aerosol is output from the outlet 103 of the mixing pipe 1.
Be equipped with two at least exports 103 through setting up hybrid tube 1 to two exports 103 of hybrid tube 1 can be connected with dust particle counter standard substance and dust particle counter determinand respectively, thereby make the aerosol of standard substance and determinand output in acquireing hybrid tube 1 under same test condition, and then test, with the accuracy nature that improves the test.
In some embodiments, the mixing tube 1 is provided with three outlets 103, wherein one outlet 103 is connected to the standard dust particle counter and the other two outlets 103 are connected to two DUTs, respectively, such that one particle output system is capable of measuring two DUTs at a time.
Any particle output system comprises at least one atomization unit, and any atomization unit can output fog-like particles containing dust particles with preset sizes, so that any particle output system can input the dust particles with the sizes required by the current test into a standard product of the dust particle counter and a product to be tested of the dust particle counter.
In some embodiments, any one particle output system comprises two atomizing units, and one end of any one mixing tube 1 is provided with two first inlets 101 for communicating the two atomizing units, so that the amount of dust particles output by the particle output system can be adjusted according to the test requirements. Two atomizing units enable the particle output system to output a larger number of dust particles. One of the atomizer units may also be turned off to reduce the amount of dust particles.
Through setting up standard particle generating device and including two at least particle output systems, arbitrary particle output system all can output the dust particle that accords with particle size distribution test requirement, and can output the dust particle that accords with dust particle number test requirement, thereby two particle output systems can carry out particle size distribution's test simultaneously, or carry out dust particle number's test simultaneously, two particle output systems also can carry out different test items simultaneously, one of them particle output system carries out particle size distribution's test promptly, another particle output system carries out dust particle number's test, therefore, make test efficiency obtain improving by a wide margin, make standard particle generating device's use value higher.
Referring to fig. 1-4, the present embodiment provides a standard particle generating apparatus comprising two particle output systems, wherein one particle output system comprises a mixing tube 1, an atomizing unit and a fan 2. Another particle output system comprises a mixing tube 1, two atomizing units and a fan 2.
One of the mixing tubes 1 is provided with a first inlet 101 and a second inlet 102 at one end and two outlets 103 at the other end, one first inlet 101 for mounting an atomizing unit.
The other mixing tube 1 is provided with two first inlets 101 and one second inlet 102 at one end and two outlets 103 at the other end, the two first inlets 101 being used for mounting two atomizing units.
Any one of the atomizing units communicates with the first inlet 101 of the mixing pipe 1 corresponding thereto to input into the mixing pipe 1 mist particles containing dust particles of a predetermined size.
Any one of the fans 2 is communicated with the second inlet 102 of the mixing pipe 1 corresponding to the fan, so as to input gas into the mixing pipe 1, so that the gas and the atomized particles in the mixing pipe 1 are mixed into aerosol, and then the aerosol is output from the outlet 103 of the mixing pipe 1. The two outlets 103 of the mixing tube 1 are respectively used for communicating a standard product of the dust particle counter and a product to be measured of the dust particle counter.
In this embodiment, it is set that any one of the particle output systems includes the atomizing unit, the atomizing unit can output the fog-like particles containing dust particles of the preset size, so that any one of the particle output systems can input the dust particles of the size required by the current test into the standard product of the dust particle counter and the product to be tested of the dust particle counter, that is, any one of the particle output systems can output the dust particles meeting the requirement of the particle size distribution measurement, and can output the dust particles meeting the requirement of the dust particle number test, according to the current test item, the size value of the dust particles output by the atomizing unit is adjusted, and thus the test requirement can be met.
This embodiment includes two at least particle output systems through setting up standard particle generating device, and arbitrary particle output system all can output the dust particle that accords with the particle size distribution measurement requirement to can output the dust particle that accords with dust particle number test requirement, thereby make this embodiment standard particle generating device can carry out the same test item simultaneously, also can carry out different test items simultaneously, thereby improved efficiency of software testing.
Specifically, the test is performed in groups, each test group comprises a standard dust particle counter and a to-be-tested dust particle counter, and the standard dust particle counter and the to-be-tested dust particle counter in each test group are connected with the same mixing pipe 1. In the test using the standard particle generating apparatus of the present embodiment, the dust particle counter test piece and the dust particle counter standard piece in the first test set are connected to the first mixing tube 1, and the dust particle counter test piece and the dust particle counter standard piece in the second test set are connected to the second mixing tube 1. The first mixing duct 1 outputs an aerosol containing airborne particles of a first size and the second mixing duct 1 outputs an aerosol containing airborne particles of a second size, and the first size and the second size may be the same or different, so that the test items in the first test set and the test items in the second test set may be the same or different. Compared with the conventional standard particle generating device which can only perform one project test at a time, the standard particle generating device in the embodiment has higher efficiency, and when one particle output system fails, the other particle output system can still be normally used, so that the production progress can be ensured to a certain extent.
Referring to fig. 2-3, in this embodiment, a shunt tube 104 and two speed reduction discs 105 are provided in any one of the mixing tubes 1. The two reduction disks 105 are spaced apart in the axial direction of the mixing tube 1. Any one of the reduction disks 105 is disposed perpendicular to the axial direction of the mixing pipe 1, and any one of the reduction disks 105 is connected to the inner wall of the mixing pipe 1. A plurality of through holes are formed in any one of the reduction gears 105. The inlet of the shunt tube 104 communicates with both the first inlet 101 and the second inlet 102 of the mixing tube 1 to receive the gas and the atomized particles.
In order to more clearly illustrate the embodiment of the present invention, the two speed-reducing discs 105 in any one mixing pipe 1 are respectively referred to as an upstream speed-reducing disc 105 and a downstream speed-reducing disc 105, and the downstream speed-reducing disc 105 is closer to the outlet 103 of the mixing pipe 1. The shunt tube 104 has a plurality of gas outlets 1041, any one gas outlet 1041 of shunt tube 104 is located the one end that the export 103 of mixing tube 1 was dorsad to upstream speed reduction disc 105, thereby gas, vaporific granule and aerosol are discharged from any one gas outlet 1041 of shunt tube 104, pass through two speed reduction discs 105 in proper order after, export 103 of rethread mixing tube 1 discharges, therefore, make the dwell time of gas and vaporific granule in mixing tube 1 longer, make gas and vaporific granule can the intensive mixing form aerosol, improve the accuracy and the efficiency of detection from this.
One end of the mixing pipe 1, which is far away from the first inlet 101 and the second inlet 102, is provided with an adjusting disc 106, the adjusting disc 106 is arranged perpendicular to the axial direction of the mixing pipe 1, the adjusting disc 106 is connected with the inner wall of the mixing pipe 1, and the adjusting disc 106 is provided with a plurality of holes penetrating through the thickness direction of the adjusting disc 106. The two outlets 103 of the mixing tube 1 penetrate the regulating disc 106, so that the aerosol in the mixing tube 1 can be output through the two outlets 103 of the mixing tube 1 and also can be output through the regulating disc 106 connected with the outlets 103, thereby preventing the dust particle counter from being damaged when the air pressure in the mixing tube 1 is too high.
Any one of the atomizing units in this embodiment includes a nozzle 3, a container 4, and a connecting tube 5. Compressed air flows through the connection pipe 5. The connection pipe 5 communicates with the first opening of the nozzle 3 to input compressed air into the nozzle 3. The container 4 communicates with the second opening of the nozzle 3 to feed the liquid containing dust particles of a predetermined size into the nozzle 3. Thus, the liquid is dispersed into atomized particles by the compressed air and is then output from the third opening of the nozzle 3, and the third opening of the nozzle 3 communicates with the first inlet 101 of the mixing pipe 1 corresponding thereto. Thus, the atomizing means can be caused to input the atomized particles containing dust particles of a predetermined size into the mixing pipe 1 by only injecting the liquid containing dust particles of a predetermined size into the container 4.
The standard particle generating device in this embodiment includes an air compressor 8, one end of any connecting pipe 5 far away from the nozzle 3 is communicated with the air compressor 8, and the air compressor 8 can input compressed air into the connecting pipe 5.
In an alternative embodiment, any one of the connection pipes 5 communicates with a compressed air storage device in which a large amount of compressed air is stored, so that the connection pipe 5 can take in the compressed air.
In this embodiment, a first regulating valve 6 is provided between any one of the connection pipes 5 and the air compressor 8 to control the flow rate of the compressed air. A first filter 7 is provided between any one of the connection pipes 5 and its corresponding nozzle 3.
In the present embodiment, three connection pipes 5 are collectively included, and the air compressor 8 is communicated with each of the three connection pipes 5, so that compressed air can be simultaneously input into the three connection pipes 5. The output end of the air compressor 8 is provided with a main filter 9, the compressed air output by the air compressor 8 passes through the main filter 9 and then is input into the three connecting pipes 5, and then any one connecting pipe 5 inputs the compressed air into the corresponding nozzle 3 through the corresponding first filter 7.
A second regulating valve 10 and a second filter 11 are sequentially arranged between any one fan 2 and the mixing pipe 1. The air inlet of any one fan 2 is also provided with a third filter 12, so that impurities in the air are filtered, and the detection accuracy is improved. The second regulating valve 10 is arranged so that the gas flow rate fed into the mixing pipe 1 can be regulated to suit the detection requirements.
The nozzle 3 of the atomizing unit in this embodiment is a nozzle 3 commonly used in atomizers in the prior art. The principle is that compressed air forms high-speed airflow through a fine nozzle of the nozzle 3, the generated negative pressure drives the solution to be sprayed onto an obstacle in the nozzle 3, and the solution splashes around under high-speed impact to change liquid drops into mist-shaped particles to be sprayed out of the nozzle 3.
A indication error detection device for dust particle counter in this embodiment can prepare into less size as required to can be lighter, portable, and can arrange in the clean district in less space and use.
The principle and the implementation mode of the utility model are explained by applying specific embodiments in the utility model, and the description of the embodiments is only used for helping to understand the technical scheme and the core idea of the utility model; meanwhile, for a person skilled in the art, according to the idea of the present invention, there may be variations in the specific embodiments and the application scope, and in summary, the content of the present specification should not be construed as a limitation to the present invention.
Claims (7)
1. A standard particle generating apparatus comprising at least two particle output systems, any one of said particle output systems comprising:
the mixing device comprises a mixing pipe, a first inlet, a second inlet, a first outlet and a second outlet, wherein one end of the mixing pipe is provided with at least one first inlet and one second inlet, and the other end of the mixing pipe is provided with at least two outlets;
at least one atomizing unit, wherein any one atomizing unit is communicated with the corresponding first inlet so as to input atomized particles into the mixing pipe, and the atomized particles contain dust particles with preset sizes; and
the fan, the fan with the second import intercommunication of hybrid tube to input gas in the hybrid tube, make gas with fog granule mixing becomes aerosol in the hybrid tube, and then follow the export output of hybrid tube.
2. The standard particle generating apparatus of claim 1, wherein a flow dividing tube and at least one speed reducing disk are disposed in any one of the mixing tubes, any one of the speed reducing disks is disposed perpendicular to an axial direction of the mixing tube, any one of the speed reducing disks is connected to an inner wall of the mixing tube, a plurality of through holes are disposed on any one of the speed reducing disks, an air inlet of the flow dividing tube is communicated with both the first inlet and the second inlet of the mixing tube to receive the air and the atomized particles, and an air outlet of the flow dividing tube is disposed at an end of one of the speed reducing disks opposite to an outlet of the mixing tube.
3. The standard particle generating apparatus according to claim 1, wherein any one of the atomizing units includes a nozzle, a container, and a connecting pipe, the connecting pipe communicates with the first opening of the nozzle to supply compressed air into the nozzle, the container communicates with the second opening of the nozzle to supply a liquid containing dust particles of a predetermined size into the nozzle, so that the liquid is dispersed into atomized particles by the compressed air and is discharged from the third opening of the nozzle, and the third opening of the nozzle communicates with the first inlet of the mixing pipe corresponding thereto.
4. The standard particle generating apparatus of claim 3, wherein the standard particle generating apparatus comprises an air compressor, and an end of any one of the connection pipes remote from the nozzle is in communication with the air compressor.
5. The standard particle generating apparatus according to claim 4, wherein a first regulating valve is provided between any one of the connection pipes and the air compressor to control a flow rate of the compressed air.
6. The standard particle generating apparatus of claim 3, wherein at least one first filter is disposed between any one of said connecting pipes and said corresponding nozzle.
7. The standard particle generating apparatus of claim 1, wherein a second regulating valve and a second filter are sequentially disposed between any one of the fans and the corresponding mixing pipe.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202121900276.7U CN215866269U (en) | 2021-08-14 | 2021-08-14 | Standard particle generating device |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202121900276.7U CN215866269U (en) | 2021-08-14 | 2021-08-14 | Standard particle generating device |
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| CN215866269U true CN215866269U (en) | 2022-02-18 |
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| CN202121900276.7U Active CN215866269U (en) | 2021-08-14 | 2021-08-14 | Standard particle generating device |
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