CN113048401A - Multichannel gas flow automatic check out system - Google Patents
Multichannel gas flow automatic check out system Download PDFInfo
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- CN113048401A CN113048401A CN202110437371.6A CN202110437371A CN113048401A CN 113048401 A CN113048401 A CN 113048401A CN 202110437371 A CN202110437371 A CN 202110437371A CN 113048401 A CN113048401 A CN 113048401A
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F17—STORING OR DISTRIBUTING GASES OR LIQUIDS
- F17D—PIPE-LINE SYSTEMS; PIPE-LINES
- F17D3/00—Arrangements for supervising or controlling working operations
- F17D3/01—Arrangements for supervising or controlling working operations for controlling, signalling, or supervising the conveyance of a product
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B64—AIRCRAFT; AVIATION; COSMONAUTICS
- B64F—GROUND OR AIRCRAFT-CARRIER-DECK INSTALLATIONS SPECIALLY ADAPTED FOR USE IN CONNECTION WITH AIRCRAFT; DESIGNING, MANUFACTURING, ASSEMBLING, CLEANING, MAINTAINING OR REPAIRING AIRCRAFT, NOT OTHERWISE PROVIDED FOR; HANDLING, TRANSPORTING, TESTING OR INSPECTING AIRCRAFT COMPONENTS, NOT OTHERWISE PROVIDED FOR
- B64F5/00—Designing, manufacturing, assembling, cleaning, maintaining or repairing aircraft, not otherwise provided for; Handling, transporting, testing or inspecting aircraft components, not otherwise provided for
- B64F5/60—Testing or inspecting aircraft components or systems
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F17—STORING OR DISTRIBUTING GASES OR LIQUIDS
- F17D—PIPE-LINE SYSTEMS; PIPE-LINES
- F17D3/00—Arrangements for supervising or controlling working operations
- F17D3/18—Arrangements for supervising or controlling working operations for measuring the quantity of conveyed product
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F17—STORING OR DISTRIBUTING GASES OR LIQUIDS
- F17D—PIPE-LINE SYSTEMS; PIPE-LINES
- F17D5/00—Protection or supervision of installations
- F17D5/005—Protection or supervision of installations of gas pipelines, e.g. alarm
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01P—MEASURING LINEAR OR ANGULAR SPEED, ACCELERATION, DECELERATION, OR SHOCK; INDICATING PRESENCE, ABSENCE, OR DIRECTION, OF MOVEMENT
- G01P21/00—Testing or calibrating of apparatus or devices covered by the preceding groups
- G01P21/02—Testing or calibrating of apparatus or devices covered by the preceding groups of speedometers
- G01P21/025—Testing or calibrating of apparatus or devices covered by the preceding groups of speedometers for measuring speed of fluids; for measuring speed of bodies relative to fluids
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Manufacturing & Machinery (AREA)
- Transportation (AREA)
- Aviation & Aerospace Engineering (AREA)
- Control Of Fluid Pressure (AREA)
Abstract
The invention discloses a multichannel gas flow automatic detection system, which comprises a pneumatic device and an electric control device, wherein the pneumatic device comprises an electric control proportional valve connected with the electric control device, a pressure reducing valve is arranged at the gas inlet end of the electric control proportional valve, and the gas outlet end of the electric control proportional valve is connected with a multichannel electromagnetic valve through a flow measuring device; a pressure transmitter connected with the electric control device is arranged between the multi-channel electromagnetic valve and the flow measuring device; the invention can realize the function of stabilizing the output pressure airflow by a single channel or multiple channels, and can adjust the pressure of the output airflow in real time, thereby effectively avoiding the breakdown of the flow tester.
Description
Technical Field
The invention belongs to the technical field of flow testing devices, and particularly relates to a multi-channel gas flow automatic detection system.
Background
At the present stage, the state vigorously develops aviation industry, and the testing capability of the aircraft component is relatively improved. The airspeed tube is composed of two concentric circular tubes, the inner circular tube is a total pressure tube, and the outer sleeve is a static pressure tube. When the airplane flies forward, the airflow rushes into the airspeed head, and the sensor at the end of the head can sense the impact force of the airflow, namely the dynamic pressure. The faster the aircraft flies, the greater the dynamic pressure.
The airspeed head is mainly used for obtaining airspeed by measuring airflow dynamic pressure, the static pressure measured by the airspeed head can also be used as a calculation parameter of an altimeter, and a 'lifting speedometer' can be manufactured by using the static pressure measured by the airspeed head, namely the speed of the change of the altitude of the airplane is measured. If the airspeed head is blocked, the correct flight speed reading cannot be displayed, and the situation is serious, so that a serious accident of machine damage and human death can be caused.
In order to avoid the mode airspeed tube from breaking down, the airspeed tube needs to be subjected to flow test, the current mode of measuring the airspeed tube flow is generally that the operating principle and the characteristic of single airspeed tube are aimed at through the technical staff who has abundant professional work experience, the atmospheric data tester is operated to give the pressure value, through flowmeter output to product, operating personnel reads flowmeter pointer reading through naked eyes. The mode of this kind of artifical test airspeed tube, the reliability is poor, and is inefficient, and the time is long, and the skill requires highly, and non-ordinary staff is competent, and traditional airspeed tube measuring device does not possess multichannel flow output's function, leads to airspeed tube detection efficiency very low.
Disclosure of Invention
The invention aims to provide a multichannel gas flow automatic detection system, which realizes the function of stably outputting pressure gas flow to carry out flow test on an airspeed tube by a single channel or multiple channels, and can adjust the pressure of the output gas flow in real time.
The invention is realized by the following technical scheme:
a multi-channel gas flow automatic detection system comprises a pneumatic device and an electric control device, wherein the pneumatic device comprises an electric control proportional valve connected with the electric control device, a pressure reducing valve is arranged at the gas inlet end of the electric control proportional valve, and the gas outlet end of the electric control proportional valve is connected with a multi-channel electromagnetic valve through a flow measuring device; and a pressure transmitter connected with the electric control device is arranged between the multi-channel electromagnetic valve and the flow measuring device.
The pneumatic system is used for providing air flow with certain pressure for the tested product, and the electric control device is used for adjusting the output pressure of the pneumatic system in real time according to the output pressure value of the pneumatic system. The air inlet end of the pressure reducing valve is connected with an air source, air generated by the air source is reduced to the maximum pressure value which can be borne by the electric control proportional valve through the pressure reducing valve, the electric control proportional valve outputs the air to the multi-channel electromagnetic valve according to the set output proportion, and single-channel or multi-channel airflow output is carried out through the multi-channel electromagnetic valve. Meanwhile, the pressure transmitter detects the value of the airflow pressure output by the multi-channel electromagnetic valve to the product in real time, converts the detected pressure value into an electric signal and transmits the electric signal to the electric control device, and the electric control device compares the actual output pressure of the multi-channel electromagnetic valve with the product demand pressure according to the received pressure electric signal and controls the output proportion of the electric control proportional valve in a feedback mode according to the comparison result.
When the actual output pressure of the multi-channel electromagnetic valve is higher than the product demand pressure, the electric control device controls the electric control proportional valve in a feedback mode to reduce the output proportion, and therefore the output pressure of the multi-channel electromagnetic valve is reduced; when the actual output pressure of the multi-channel electromagnetic valve is lower than the product demand pressure, the electric control device controls the electric control proportional valve in a feedback mode to increase the output proportion, and then the output pressure of the multi-channel electromagnetic valve is increased until the output pressure of the multi-channel electromagnetic valve is equal to the product demand pressure, and the output proportion of the electric control proportional valve is controlled in a feedback mode by the electric control device to be kept constant at the moment, so that the output pressure of the multi-channel electromagnetic valve is kept constant.
In order to better realize the invention, the electric control device further comprises a PLC controller, a proportional valve controller connected with the electric control proportional valve, a feedback control module connected with the PLC controller and a switching value output control module, wherein the feedback control module is respectively connected with the pressure transmitter, the proportional valve controller and one output channel of the multi-channel electromagnetic valve; and the switching value output control module is connected with the rest output channels of the multi-channel electromagnetic valve.
In order to better implement the present invention, further, the multi-channel solenoid valve includes eight output channels, the switching value output control module includes seven control interfaces, the seven control interfaces of the switching value output control module are respectively connected with seven output channels of the multi-channel solenoid valve, and the feedback control module is connected with one output channel of the multi-channel solenoid valve.
In order to better realize the invention, further, the feedback control module comprises an AD feedback control module and a DA output control module, a transmitting port of the AD feedback control module is connected with the pressure transmitter, and a feedback port of the AD feedback control module is connected with the proportional valve controller; an output control port of the DA output control module is connected with the proportional valve controller, and a switching value control port of the DA output control module is connected with one output channel of the multi-channel electromagnetic valve.
In order to better implement the invention, the pressure transmitter further comprises a direct current power supply connected with the pressure transmitter.
In order to better realize the invention, further, an air cylinder is arranged at the air inlet end of the pressure reducing valve, and a pressure gauge is arranged at the air outlet end of the pressure reducing valve.
Compared with the prior art, the invention has the following advantages and beneficial effects:
(1) according to the invention, the output airflow pressure of the multi-channel electromagnetic valve is detected in real time through the pressure transmitter, meanwhile, the product demand pressure is preset and configured in the PLC, the PLC can feedback control the output proportion of the electric control proportional valve according to the difference value between the preset and configured product demand pressure and the output airflow pressure of the multi-channel electromagnetic valve, and then the output airflow pressure of the multi-channel electromagnetic valve is adjusted to be matched with the product demand pressure, so that the whole airflow output pressure is adjusted more efficiently and accurately, and the adjustment of the airflow pressure is more convenient and rapid;
(2) the invention sets a switching value output control module, connects with the corresponding output channel in the multi-channel electromagnetic valve through a plurality of switching value output interfaces in the switching value output control module, and directly connects with the remaining output channel in the multi-channel electromagnetic valve through the switching value output interface in the feedback control module; the on-off of a plurality of output channels in the multi-channel electromagnetic valve is controlled through a plurality of switching value output interfaces in the switching value output control module, single-channel or multi-channel airflow output is achieved, meanwhile, the on-off of one output channel in the multi-channel electromagnetic valve is controlled through the switching value output interface in the feedback control module, even if the switching value output control module fails, at least one output channel of the multi-channel electromagnetic valve can be guaranteed to keep normal work, and the breakdown of the whole flow tester is effectively avoided.
Drawings
FIG. 1 is a schematic view of the overall structure of the present invention;
fig. 2 is a schematic circuit structure diagram of the electric control device.
Wherein: 1-an electrically controlled proportional valve; 2-a pressure reducing valve; 3-a flow measuring device; 4-a multi-channel electromagnetic valve; 5-a pressure transmitter; 6-an electric control device; 7-a gas cylinder; 61-a PLC controller; 62-proportional valve controller; 63-a feedback control module; 64-switching value output control module; 65-a direct current power supply; 631-AD feedback control module; 632-DA output control module.
Detailed Description
Example 1:
the multichannel gas flow automatic detection system of the embodiment, as shown in fig. 1, includes a pneumatic device and an electric control device 6, the pneumatic device includes an electric control proportional valve 1 connected with the electric control device 6, an air inlet end of the electric control proportional valve 1 is provided with a pressure reducing valve 2, and an air outlet end of the electric control proportional valve 1 is connected with a multichannel electromagnetic valve 4 through a flow measuring device 3; and a pressure transmitter 5 connected with an electric control device 6 is arranged between the multi-channel electromagnetic valve 4 and the flow measuring device 3.
The inlet end and the air supply of relief pressure valve 2 are connected, and the gas of air supply carries out the maximum pressure value that relief pressure valve 2 decompression can bear to automatically controlled proportional valve 1, then automatically controlled proportional valve 1 exports the air current of specific pressure to multichannel solenoid valve 4 according to the output proportion that sets for, and multichannel solenoid valve 4 includes a plurality of output channel, through the switching of controlling a plurality of output channel, can realize single channel or multichannel to the product air feed. Meanwhile, the flow rate of gas entering the multi-channel electromagnetic valve 4 is detected in real time through the flow measuring device 3, the input pressure of the multi-channel electromagnetic valve 4 is converted into an electric signal through the pressure transmitter 5 and is transmitted to the electric control device 6, the electric control device 6 and the electric control proportional valve 1, the electric control device 6 feeds back and adjusts the output pressure value of the electric control proportional valve 1 according to the received pressure value in real time, until the pressure value fed back by the pressure transmitter 5 reaches the product gas supply pressure value, the electric control device 6 controls the output proportion of the electric control proportional valve 1 to be kept constant at the moment, and further the output pressure of the multi.
Example 2:
the embodiment is further optimized on the basis of embodiment 1, as shown in fig. 2, the electric control device 6 includes a PLC controller 61, a proportional valve controller 62 connected to the electric control proportional valve 1, a feedback control module 63 connected to the PLC controller 61, and a switching value output control module 64, where the feedback control module 63 is respectively connected to the pressure transmitter 5, the proportional valve controller 62, and one output channel of the multi-channel electromagnetic valve 4; the switching value output control module 64 is connected with the rest output channels of the multi-channel solenoid valve 4.
Meanwhile, a switching value output control module 64 is arranged corresponding to N (N is more than or equal to 2) output channels of the multi-channel electromagnetic valve 4, the switching value output control module 64 comprises N-1 switching value output interfaces, the N-1 switching value output interfaces are connected with the N-1 output channels of the multi-channel electromagnetic valve 4 to control the on-off of the output channels, and meanwhile, a switching value output interface connected with the rest output channels of the multi-channel electromagnetic valve 4 is arranged in the feedback control module 63. The switching on and off of the N output channels of the multi-channel electromagnetic valve 4 are synchronously controlled by the switching value output control module 64 and the feedback control module 63, even if the switching value output control module 64 breaks down, one of the output channels of the multi-channel electromagnetic valve 4 can be controlled by the feedback control module 63, and the failure of the whole multi-channel flow tester is avoided.
Further, the multi-channel solenoid valve 4 includes eight output channels, the switching value output control module 64 includes seven control interfaces, the seven control interfaces of the switching value output control module 64 are respectively connected with seven output channels of the multi-channel solenoid valve 4, and the feedback control module 63 is connected with one of the output channels of the multi-channel solenoid valve.
Further, the PLC controller 61 is connected to the feedback control module 63 and the switching value output control module 64 through RS485 interfaces.
Further, the model of the switching value output control module 64 is I-7067D, the model of the multi-channel electromagnetic valve 4 is GAB412, the model of the pressure transmitter 5 is MPM489, and the model of the proportional valve controller 62 is GVR-2500.
Other parts of this embodiment are the same as embodiment 1, and thus are not described again.
Example 3:
this embodiment is further optimized based on the above embodiment 1 or 2, as shown in fig. 2, the feedback control module 63 includes an AD feedback control module 631 and a DA output control module 632, a transmitting port of the AD feedback control module 631 is connected to the pressure transmitter 5, and a feedback port of the AD feedback control module 631 is connected to the proportional valve controller 62; an output control port of the DA output control module 632 is connected to the proportional valve controller 62, and a switching value control port of the DA output control module 632 is connected to one output channel of the multi-channel solenoid valve 4.
The DA output control module 632 provides analog voltage to the electrically controlled proportional valve 1 through the proportional valve controller 62 according to the voltage characteristic of the electrically controlled proportional valve 1, so as to adjust the output proportion of the electrically controlled proportional valve 1, and further adjust the output pressure value of the multi-channel solenoid valve 4. Meanwhile, the switching value control port of the DA output control module 632 is connected to one of the output channels of the multi-channel solenoid valve 4 and controls the on/off of the corresponding output channel.
The pressure value output by the multi-channel solenoid valve 4 is converted into analog quantity by the pressure transmitter 5 and then is transmitted to the PLC controller 61 by the AD feedback control module 631, if the pressure value output by the multi-channel solenoid valve 4 is lower than the product demand pressure, the PLC controller 61 inputs a pressurization signal to the electric control proportional valve 1 by the AD feedback control module 631, at the moment, the output proportion of the electric control proportional valve 1 is increased, and the output pressure of the multi-channel solenoid valve 4 is further increased; if the pressure value output by the multi-channel solenoid valve 4 is higher than the product demand pressure, the PLC controller 61 inputs a pressure reduction signal to the electronic control proportional valve 1 through the AD feedback control module 631, and at this time, the output proportion of the electronic control proportional valve 1 is reduced, so that the output pressure of the multi-channel solenoid valve 4 is reduced.
When the output pressure of the multi-channel solenoid valve 4 is equal to the product demand pressure, the PLC controller 61 inputs a voltage stabilization signal to the electric control proportional valve 1 through the AD feedback control module 631, and the output proportion of the electric control proportional valve 1 is kept constant at this time, so that the output pressure of the multi-channel solenoid valve 4 is kept constant.
Furthermore, the model of the AD feedback control module 631 is I-7017, and the model of the DA output control module 632 is M-7024U.
The rest of this embodiment is the same as embodiment 1 or 2, and therefore, the description thereof is omitted.
Example 4:
the present embodiment is further optimized on the basis of any one of the above embodiments 1 to 3, and as shown in fig. 2, the present embodiment further includes a dc power supply 65 connected to the pressure transmitter 5, and supplies power to the pressure transmitter 5, the feedback control module 63, the switching value output control module 64, and the PLC controller 61 through the dc power supply 65.
Further, the dc power supply 65 is a 24V dc power supply 65.
Further, as shown in fig. 1, an air cylinder 7 is arranged at an air inlet end of the pressure reducing valve 2, the air cylinder 7 is used as an air source to input air flow with pressure of 10Mpa to the pressure reducing valve 2, and a pressure gauge is arranged at an air outlet end of the pressure reducing valve 2 and used for detecting the air flow pressure in real time.
Other parts of this embodiment are the same as any of embodiments 1 to 3, and thus are not described again.
The above description is only a preferred embodiment of the present invention, and is not intended to limit the present invention in any way, and all simple modifications and equivalent variations of the above embodiments according to the technical spirit of the present invention are included in the scope of the present invention.
Claims (6)
1. A multi-channel gas flow automatic detection system comprises a pneumatic device and an electric control device (6), and is characterized in that the pneumatic device comprises an electric control proportional valve (1) connected with the electric control device (6), a pressure reducing valve (2) is arranged at the air inlet end of the electric control proportional valve (1), and the air outlet end of the electric control proportional valve (1) is connected with a multi-channel electromagnetic valve (4) through a flow measuring device (3); and a pressure transmitter (5) connected with an electric control device (6) is arranged between the multi-channel electromagnetic valve (4) and the flow measuring device (3).
2. The multi-channel gas flow automatic detection system according to claim 1, characterized in that the electric control device (6) comprises a PLC controller (61), a proportional valve controller (62) connected with the electric control proportional valve (1), a feedback control module (63) connected with the PLC controller (61) and a switching value output control module (64), wherein the feedback control module (63) is respectively connected with the pressure transmitter (5), the proportional valve controller (62) and one output channel of the multi-channel electromagnetic valve (4); and the switching value output control module (64) is connected with the rest output channels of the multi-channel electromagnetic valve (4).
3. A multi-channel gas flow automatic detection system according to claim 2, characterized in that the multi-channel solenoid valve (4) comprises eight output channels, the switching value output control module (64) comprises seven control interfaces, the seven control interfaces of the switching value output control module (64) are respectively connected with seven output channels of the multi-channel solenoid valve (4), and the feedback control module (63) is connected with one of the output channels of the multi-channel solenoid valve (4).
4. The multi-channel gas flow automatic detection system according to claim 3, characterized in that the feedback control module (63) comprises an AD feedback control module (631) and a DA output control module (632), the transmitting port of the AD feedback control module (631) is connected with the pressure transmitter (5), the feedback port of the AD feedback control module (631) is connected with the proportional valve controller (62); an output control port of the DA output control module (632) is connected with the proportional valve controller (62), and a switching value control port of the DA output control module (632) is connected with one output channel of the multi-channel electromagnetic valve (4).
5. A multi-channel automatic gas flow detection system according to any of claims 1-4, characterized by further comprising a DC power supply (65) connected to the pressure transmitter (5).
6. A multi-channel automatic gas flow detection system according to any one of claims 1-4, characterized in that a gas cylinder (7) is arranged at the gas inlet end of the pressure reducing valve (2), and a pressure gauge is arranged at the gas outlet end of the pressure reducing valve (2).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110437371.6A CN113048401A (en) | 2021-04-22 | 2021-04-22 | Multichannel gas flow automatic check out system |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110437371.6A CN113048401A (en) | 2021-04-22 | 2021-04-22 | Multichannel gas flow automatic check out system |
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| Publication Number | Publication Date |
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| CN113048401A true CN113048401A (en) | 2021-06-29 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN202110437371.6A Pending CN113048401A (en) | 2021-04-22 | 2021-04-22 | Multichannel gas flow automatic check out system |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116819951A (en) * | 2023-08-28 | 2023-09-29 | 新光维医疗科技(苏州)股份有限公司 | Flow control method, system, device and storage medium for gas delivery system |
| CN117073921A (en) * | 2023-10-16 | 2023-11-17 | 成都睿宝电子科技有限公司 | Automatic calibration testing device and method based on helium mass spectrometer leak detector |
-
2021
- 2021-04-22 CN CN202110437371.6A patent/CN113048401A/en active Pending
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116819951A (en) * | 2023-08-28 | 2023-09-29 | 新光维医疗科技(苏州)股份有限公司 | Flow control method, system, device and storage medium for gas delivery system |
| CN116819951B (en) * | 2023-08-28 | 2023-11-24 | 新光维医疗科技(苏州)股份有限公司 | Flow control method, system, device and storage medium for gas delivery system |
| CN117073921A (en) * | 2023-10-16 | 2023-11-17 | 成都睿宝电子科技有限公司 | Automatic calibration testing device and method based on helium mass spectrometer leak detector |
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