CN116839831A - Voltage-stabilizing type air leakage detection system - Google Patents
Voltage-stabilizing type air leakage detection system Download PDFInfo
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- CN116839831A CN116839831A CN202310878905.8A CN202310878905A CN116839831A CN 116839831 A CN116839831 A CN 116839831A CN 202310878905 A CN202310878905 A CN 202310878905A CN 116839831 A CN116839831 A CN 116839831A
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- 238000001514 detection method Methods 0.000 title claims abstract description 134
- 238000009423 ventilation Methods 0.000 claims abstract description 30
- 230000035699 permeability Effects 0.000 claims description 14
- 230000001105 regulatory effect Effects 0.000 claims description 10
- 230000006835 compression Effects 0.000 claims description 8
- 238000007906 compression Methods 0.000 claims description 8
- 238000003825 pressing Methods 0.000 claims description 8
- 230000001276 controlling effect Effects 0.000 claims description 3
- 235000019504 cigarettes Nutrition 0.000 abstract description 41
- 230000007547 defect Effects 0.000 abstract description 5
- 239000007789 gas Substances 0.000 description 20
- 238000005259 measurement Methods 0.000 description 6
- 239000000779 smoke Substances 0.000 description 6
- 238000010586 diagram Methods 0.000 description 5
- 238000000034 method Methods 0.000 description 5
- 230000008569 process Effects 0.000 description 5
- 241000208125 Nicotiana Species 0.000 description 4
- 235000002637 Nicotiana tabacum Nutrition 0.000 description 4
- 238000009434 installation Methods 0.000 description 4
- 238000012986 modification Methods 0.000 description 3
- 230000004048 modification Effects 0.000 description 3
- 238000012360 testing method Methods 0.000 description 3
- 230000007423 decrease Effects 0.000 description 2
- 230000003247 decreasing effect Effects 0.000 description 2
- 238000013461 design Methods 0.000 description 2
- 238000007789 sealing Methods 0.000 description 2
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000033228 biological regulation Effects 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 238000012937 correction Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000003546 flue gas Substances 0.000 description 1
- 239000003292 glue Substances 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 239000010979 ruby Substances 0.000 description 1
- 229910001750 ruby Inorganic materials 0.000 description 1
- 230000000391 smoking effect Effects 0.000 description 1
- 238000011895 specific detection Methods 0.000 description 1
- 230000000087 stabilizing effect Effects 0.000 description 1
- 230000009466 transformation Effects 0.000 description 1
- 238000011144 upstream manufacturing Methods 0.000 description 1
Classifications
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
- G01M3/00—Investigating fluid-tightness of structures
- G01M3/02—Investigating fluid-tightness of structures by using fluid or vacuum
- G01M3/26—Investigating fluid-tightness of structures by using fluid or vacuum by measuring rate of loss or gain of fluid, e.g. by pressure-responsive devices, by flow detectors
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- Manufacturing Of Cigar And Cigarette Tobacco (AREA)
Abstract
The application relates to a pressure-stabilizing type air leakage detection system, wherein a front detection small cap and a rear detection small cap are oppositely arranged on a detection wheel, an inlet of a pressure generating device is connected with an air source, an outlet of the pressure generating device is connected with an inlet of a capacity module, an outlet of the capacity module is connected with a gas inlet of a mixing nozzle through a pipeline, a gas outlet of the mixing nozzle is connected with the front detection small cap through a pipeline, and an inlet pressure/voltage converter is communicated with a pipeline between the gas outlet of the mixing nozzle and the front detection small cap; the rear detection small cap is connected with the Venturi nozzle outlet through a pipeline, an outlet pressure/voltage converter is arranged on the pipeline, and the Venturi nozzle inlet is connected with the precompaction device outlet through a pipeline. Through the technical scheme, the reliability of the air leakage detection system is improved, and meanwhile, the detection of the total ventilation and the suction resistance is integrated, so that the internal quality of cigarettes can be effectively controlled, cigarettes with quality defects are removed, and the suction resistance standard deviation is improved.
Description
Technical Field
The application belongs to the technical field of cigarette machine detection, and particularly relates to a pressure-stabilizing type air leakage detection system.
Background
The ZJ17 cigarette machine set used at present is from taking cigarette detecting system, is electronic circuit board card design, and the reliability is poor, and the commonality is not strong and maintain inconveniently, and the cigarette detecting system of this cigarette machine can not carry out ventilation degree and suction resistance function detection simultaneously.
In the prior art, the empty head, the air leakage, the ventilation degree, the suction resistance, the mouth shortage and the like of the cigarette are detected directly, but the detection of the ventilation degree and the suction resistance needs special equipment, and conflicts with the detection set of the ventilation degree, so that the air leakage detection, the ventilation degree detection and the suction resistance detection are not completely integrated into an integrated system in the existing cigarette machine set.
On the other hand, in the air leakage detection air pressure supply of the ZJ17 cigarette machine set, the air pressure of 4bar supplied by the machine set is directly sent to a detection wheel through a precise pressure regulating valve to serve as an air source for air leakage detection, the air pressure for measuring cigarettes is not fixed, and the air inlet pressure is regulated according to a detection result. The defects are that: fluctuation of air pressure of the unit and smoke removal in MAX in the running process of the unit can be positively brought to detection of the fluctuation of the air pressure, so that detection accuracy is affected.
Disclosure of Invention
The application aims to provide a pressure-stabilizing type air leakage detection system, which aims to solve the problems that in the prior art, the fluctuation of air pressure of a unit and smoke in MAX in the running process of the unit are detected, so that the detection accuracy is affected.
In order to achieve the above purpose, the application is realized by the following technical scheme:
a pressure-stabilizing type air leakage detection system comprises a pressure generating device, a capacity module, a mixing nozzle, an inlet pressure/voltage converter, a front detection small cap, a rear detection small cap, an outlet pressure/voltage converter, a venturi nozzle and a pre-pressing device;
the front detection small cap and the rear detection small cap are oppositely arranged on the detection wheel, an inlet of the pressure generating device is connected with an air source, an outlet of the pressure generating device is connected with an inlet of the capacity module, an outlet of the capacity module is connected with a gas inlet of the mixing nozzle through a pipeline, a natural air inlet is arranged on the mixing nozzle, a gas outlet of the mixing nozzle is connected with the front detection small cap through a pipeline, and an inlet pressure/voltage converter is communicated with the pipeline between the gas outlet of the mixing nozzle and the front detection small cap;
the rear detection small cap is connected with the Venturi nozzle outlet through a pipeline, an outlet pressure/voltage converter is arranged on the pipeline, and the Venturi nozzle inlet is connected with the precompaction device outlet through a pipeline.
Further, the detection system comprises an air permeability detection system, a total ventilation detection system and a suction resistance detection system;
the air permeability detection system consists of a pressure generating device, a capacity module, a mixing nozzle, a front detection small cap, a rear detection small cap and an outlet/voltage converter;
the total ventilation degree detection system consists of a pressure generating device, a capacity module, an inlet pressure/voltage converter, a front detection small cap, a rear detection small cap and an outlet pressure/voltage converter;
the suction resistance detection system consists of a pre-pressing device, a Venturi nozzle, an outlet pressure/voltage converter, a front detection small cap and a rear detection small cap.
Further, the pressure generating device controls the air source provided by the machine platform to generate a stabilized pressure air source 1700+/-20 pa by controlling a stepping motor valve and an air pressure feedback signal.
Further, the capacity module is a gas volume, and the volume is >0.2L.
Further, the venturi nozzle produced a steady flow of 17.5ml/s with a nozzle diameter of 0.2mm.
Further, the pre-compression device provides a stable pre-compression with a strength of 210 kPa.
Further, the inlet pressure/voltage converter and the outlet pressure/voltage converter are electrically connected with a controller.
Compared with the prior art, the application has the beneficial effects that:
through the technical scheme, the reliability of the air leakage detection system is improved, and meanwhile, the detection of the total ventilation and the suction resistance is integrated, so that the internal quality of cigarettes can be effectively controlled, cigarettes with quality defects are removed, and the suction resistance standard deviation is improved.
Drawings
FIG. 1 is a schematic diagram illustrating an installation of a pressure-stabilized air leakage detection system according to the present application.
Fig. 2 is a schematic view of a pressure generating apparatus.
Fig. 3 is a schematic diagram of a capacity module structure.
FIG. 4 is a schematic diagram of an air permeability detection system according to the present application.
Fig. 5 is a schematic diagram of the principle of total ventilation detection.
Fig. 6 is a schematic diagram of the principle of detection of the resistance to suction.
Reference numerals illustrate:
1. a detection wheel; 2. a front arcuate detection plate; 3. a rear arcuate detection plate; 4. a capacity module; 5. a pressure generating device; 6. an inlet of the pressure generating device; 7. a stepper motor valve; 8. a mixing nozzle; 9. front detection cap; 10. a cigarette; 11. detecting the cap afterwards; 12. an outlet pressure/voltage converter; 13. an inlet pressure/voltage converter; 14. a venturi nozzle; 15. a ZW pre-pressing unit; 81. a nozzle hole; 82. and a side air hole.
Detailed Description
The following detailed description of the present application is provided by way of example only, and is not to be construed as limiting the scope of the application.
The technical scheme is an improved design aiming at the problem that the detection and rejection of the air leakage detection on the ZJ17 unit are inaccurate. The ZJ17 unit was not improved in the device that originally provided a gas pressure of 4bar, and still provided a gas pressure of 4bar for the new improved device.
As shown in fig. 1, the present application provides a pressure-stabilizing air leakage detecting system, in which the installation of the front detecting small cap 9 and the rear detecting small cap 11 on the detecting wheel 1 is in the prior art, the installation structures are not improved, the installation modes of the front detecting small cap, the rear detecting small cap and the detecting wheel are all clear to those skilled in the art, and meanwhile, in the detecting process, the mode of providing the cigarettes 10 to the detecting wheel 1 and the operation mode of the detecting wheel 1 are both in the prior art, and the present application does not involve the improvement of the parts.
As shown in fig. 2, the present application is provided with a pressure generating device 5, the inlet 6 of which is connected to a gas source, and the outlet of which is connected to the inlet of the capacity module. The pressure generating device controls the machine to provide an air source and generates a stabilized pressure air source 1700+/-20 pa by controlling the stepping motor valve 7 and an air pressure feedback signal. The circuit principle that the air pressure of the air pressure feedback signal is converted into voltage is the prior art. The circuit provides +/-15 Vdc voltage from the outside and outputs 0-3V to a detection control system, and the detection control system controls the opening depth of the air tightness pressure regulating valve according to the fed back voltage value, so that the air pressure is controlled, and finally, a stable air pressure source is achieved.
As shown in fig. 3, the capacity module 4 of the present application is actually a gas volume, and provides a gas volume of the air tightness detection gas source (1700±20pa), and the volume size is >0.2L. And placing a sealing gasket at the air passage opening of the volume module, aligning to the hole site, installing a pressure generating device on the sealing gasket, fixing by using 2M 6 x 25 inner hexagon screws, connecting an phi 8 air pipe, and connecting an 8-core connecting wire on the volume module, a 2-core power wire of the stop valve, a 5-core connecting wire of the pressure regulating valve and a 4-core connecting wire on the air leakage detection air source pressure sensor to the terminal row.
As shown in fig. 4 and 5, the outlet of the capacity module 4 is connected with the gas inlet of the mixing nozzle 8 through a pipeline, a natural air inlet is arranged on the mixing nozzle 8, the gas outlet of the mixing nozzle 8 is connected with the front detection small cap through a pipeline, and an inlet pressure/voltage converter 13 is communicated with the pipeline between the gas outlet of the mixing nozzle and the front detection small cap; the rear detection cap 11 is connected with the outlet of the Venturi nozzle 14 through a pipeline, an outlet pressure/voltage converter 12 is arranged on the pipeline, and the inlet of the Venturi nozzle is connected with the outlet of the pre-pressing device through a pipeline.
The pressure-stabilizing type air leakage detection system comprises an air permeability detection system, a total ventilation detection system and a suction resistance detection system.
The air permeability detection system consists of a pressure generating device, a capacity module, a mixing nozzle, a front detection small cap, a rear detection small cap and an outlet/voltage converter.
The total ventilation detection system consists of a pressure generating device, a capacity module, an inlet pressure/voltage converter, a front detection small cap, a rear detection small cap and an outlet pressure/voltage converter.
The suction resistance detection system consists of a pre-pressing device, a Venturi nozzle, an outlet pressure/voltage converter, a front detection small cap and a rear detection small cap.
The general ventilation detection principle is for filter cigarettes with ventilation zones. The total ventilation is determined by the fresh air (mixed air) content in the flue gas; the smoke is the smoke inhaled by the smoker through the cigarette holder.
The total ventilation V consists of the ventilation of the tobacco portion VT and the ventilation of the filter portion VF.
V≈VT+VF；
The amount of air passing through the cigarettes at the time of measurement was 17.5ml/s. Three cavities are distributed around the cigarette. In this way, the following ventilation can be determined by air quantity measurement:
filter tip region→filter tip ventilation degree;
tobacco shred area- & gtventilation degree of tobacco rod sections;
whole cigarette → total ventilation.
The measurement of the total ventilation is in principle the same as the measurement of the ventilation. The only difference is that the total air permeability measurement must be performed without pre-resistance (mixing nozzle). Since the ventilation and the total ventilation are measured at the same measuring station, an additional inlet pressure/voltage converter must be inserted into the measuring circuit between the mixing nozzle and the ignition end. With this inlet pressure/voltage converter the actual inlet pressure can be measured.
As shown in fig. 6, the suction resistance was measured by stabilizing the pre-compression at an intensity of 210kPa and letting it be ejected through a very small venturi nozzle 14 (ruby nozzle diameter=0.2 mm). The pre-compression of this strength and the nozzle diameter of this size gives an air volume of exactly 17.5ml/s, which is the same as the air volume used in the laboratory, which is injected into the filter end of the cigarette 10. The resistance measured at the filter end by the outlet pressure/voltage converter 12 is the suction resistance and the pre-compression is smoothed by means of the ZW pre-compression unit 15.
The specific detection process comprises the following steps:
after the cigarettes are transferred to the detection wheel from the turning wheel, the cigarettes in the cigarette grooves of the detection wheel are clung to the front and rear detection caps, and when the detection wheel rotates, the cigarettes are pressed towards the detection caps to form airtight.
Compressed air is blown to the cigarettes when the cigarettes pass through the area between the two arched detection plates, and the detection system processor keeps the detection pressure (air inlet pressure) of the compressed air blown to the cigarettes to be a constant pressure by means of the signal transmitter and the correction element of the air inlet pressure regulating system. The intake pressure regulation system provides detection pressures for air leakage detection and ventilation detection (D/GV) and resistance to suction detection (ZW), respectively.
The measured pressure developed on the cigarette is converted via an outlet pressure/voltage converter (pressure value to voltage value) located at the arcuate sensing plate into a proportional voltage value that is read once per clock cycle by the sensing system processor. The shaft encoder mounted on the test wheel shaft generates signals from which clock pulses are generated that determine the (test) cycle time of the test system processor. The air pressure measured at the gap between two cigarettes (the outlet of the pressure sensor) is used as a reference value, and the final result is obtained by calculating the difference between the two pressures measured at the gap between the cigarettes (the cigarettes themselves).
And (3) construction of a suction resistance detection air source:
according to the measurement of the suction resistance in national standard, under the standard condition, when a stable air flow with the flow rate of 17.5ml/s flows through the pressure difference at two ends of the cigarette sample, the suction resistance of the sample is obtained. So a stable airflow of 17.5ml/s is required for measuring the resistance to smoking. A steady flow of 17.5ml/s was produced in this project using a sonic venturi nozzle.
The critical pressure ratio and its calculation formula the gas flow rate at the throat will increase as the throttling pressure ratio (i.e. the ratio of the outlet pressure P1 to the upstream stagnation pressure P0) decreases when the gas flow is at subsonic. When the throttle pressure ratio decreases to a certain value, the throat flow rate reaches a maximum flow rate, the sonic speed, i.e. a so-called critical flow is reached, at which point if P0 is unchanged, the flow rate will remain unchanged by further decreasing P1 (i.e. further decreasing the throttle pressure ratio), i.e. the flow rate is no longer affected by the downstream pressure. The venturi nozzle at this time is called a sonic venturi nozzle, also called a critical flow venturi nozzle, and the throttle pressure ratio at this time is called a critical pressure ratio.
Under practical conditions, the mass flow formula of the sonic venturi nozzle:
qmi the mass flow rate (kg/s) of the sonic venturi nozzle under ideal conditions, P0 the absolute pressure of the gas stagnation (Pa) before the sonic venturi nozzle, T0 the absolute temperature of the gas stagnation (K) RM- - -the gas constant (J/(kg X K)) before the sonic venturi nozzle, the mass flow rate under actual conditions, A the throat area (m 2) of the sonic venturi nozzle, C i- - -the critical flow function of the gas under ideal conditions:
it can be seen from the formula that, under the condition that the medium is certain (air and temperature is unchanged), the constant flow and the gas stagnation absolute pressure in front of the sonic venturi nozzle are proportional to the throat area of the sonic venturi nozzle. In this embodiment, a standard sonic venturi nozzle with a diameter of 0.2mm is selected, and a stable air flow with a flow rate of 17.5ml/s is required to be output through a look-up table, so that the air stagnation absolute pressure in front of the sonic venturi nozzle needs to be 311Kpa, namely, the difference between the air stagnation absolute pressure and the atmospheric pressure is 210Kpa, which is why the suction resistance detection air source needs to be controlled at 210 Kpa.
The air permeability is approximately equal to 100% -the total air permeability.
Adding a function detection junction presentation mode (software, period and program):
the air pressure is detected by hardware and converted into a voltage signal to be transmitted to software for calculation.
The air permeability detection system using the technology can more accurately detect the air leakage smoke and improve the detection precision. The increased total ventilation detection can detect defects such as ventilation in the filter region (in the presence of a ventilation zone), defects in the filter region (e.g., air bubbles or tipping paper unwinding), porosity of the cigarette paper, location and size of holes in the cigarette paper, unsealed (slotted) glue seals, and poorly cut lit ends. The cigarette quality index of tobacco shred density, filter tip material difference, air permeability (under the condition of air permeability zone) and porosity of cigarette paper of the cigarette can be detected by increasing the suction resistance detection, so that the cigarette quality is improved.
The pressure-stabilizing type air leakage detection scheme is adopted in air leakage detection, and air leakage detection air pressure supply is that air pressure of a unit 4bar is regulated to be constant 1.7kpa through a pre-pressing generating device and is input into an air storage chamber (a capacity module) and then is conveyed to an ignition end of a cigarette for detecting air leakage of the cigarette. Compared with the prior art, the pressure-stabilizing type air leakage detection air pressure system has an automatic adjusting function, so that stable air pressure (1.7 kpa) can be obtained. The fluctuation of the air pressure of the unit and the smoke removing action of the MAX high-speed valve in the running process of the unit can not bring the fluctuation of the detected air pressure, so that the detection precision of the system is higher than that before transformation.
The present application is not limited to the above embodiments, but is not limited to the above embodiments, and any person skilled in the art will have obvious modifications and modifications equivalent to those of the equivalent embodiments, and can make various changes and modifications without departing from the scope of the present application.
Claims (7)
1. The pressure-stabilizing type air leakage detection system is characterized by comprising a pressure generating device, a capacity module, a mixing nozzle, an inlet pressure/voltage converter, a front detection small cap, a rear detection small cap, an outlet pressure/voltage converter, a venturi nozzle and a pre-pressing device;
the front detection small cap and the rear detection small cap are oppositely arranged on the detection wheel, an inlet of the pressure generating device is connected with an air source, an outlet of the pressure generating device is connected with an inlet of the capacity module, an outlet of the capacity module is connected with a gas inlet of the mixing nozzle through a pipeline, a natural air inlet is arranged on the mixing nozzle, a gas outlet of the mixing nozzle is connected with the front detection small cap through a pipeline, and an inlet pressure/voltage converter is communicated with the pipeline between the gas outlet of the mixing nozzle and the front detection small cap;
the rear detection small cap is connected with the Venturi nozzle outlet through a pipeline, an outlet pressure/voltage converter is arranged on the pipeline, and the Venturi nozzle inlet is connected with the precompaction device outlet through a pipeline.
2. The pressure-stabilized air leakage detection system according to claim 1, wherein the detection system comprises an air permeability detection system, a total air permeability detection system, and a suction resistance detection system;
the air permeability detection system consists of a pressure generating device, a capacity module, a mixing nozzle, a front detection small cap, a rear detection small cap and an outlet/voltage converter;
the total ventilation degree detection system consists of a pressure generating device, a capacity module, an inlet pressure/voltage converter, a front detection small cap, a rear detection small cap and an outlet pressure/voltage converter;
the suction resistance detection system consists of a pre-pressing device, a Venturi nozzle, an outlet pressure/voltage converter, a front detection small cap and a rear detection small cap.
3. The pressure-stabilized air leakage detection system according to claim 1, wherein the pressure generating device controls the air source provided by the machine to generate 1700+ -20 pa of pressure-stabilized air source by controlling the stepping motor valve and the air pressure feedback signal.
4. The pressure regulated leak detection system of claim 1, wherein the capacity module is a gas volume, the volume being >0.2L.
5. A pressure regulated air leakage detection system according to claim 1, wherein the venturi nozzle generates a stable air flow of 17.5ml/s, the nozzle diameter being 0.2mm.
6. The pressure regulated air leakage detection system according to claim 1, wherein said pre-compression means provides a stable pre-compression having a strength of 210 kPa.
7. The pressure regulated gas leakage detection system according to claim 1, wherein the inlet pressure/voltage converter and the outlet pressure/voltage converter are both in electrical signal connection with a controller.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310878905.8A CN116839831A (en) | 2023-07-18 | 2023-07-18 | Voltage-stabilizing type air leakage detection system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310878905.8A CN116839831A (en) | 2023-07-18 | 2023-07-18 | Voltage-stabilizing type air leakage detection system |
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| CN116839831A true CN116839831A (en) | 2023-10-03 |
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|---|---|---|---|
| CN202310878905.8A Pending CN116839831A (en) | 2023-07-18 | 2023-07-18 | Voltage-stabilizing type air leakage detection system |
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- 2023-07-18 CN CN202310878905.8A patent/CN116839831A/en active Pending
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