A multi-channel gas flow automatic detection system

Abstract

The present invention discloses a multi-channel gas flow automatic detection system, comprising a pneumatic device and an electric control device, wherein the pneumatic device comprises an electric control proportional valve connected to the electric control device, the air inlet end of the electric control proportional valve is provided with a pressure reducing valve, and the air outlet end of the electric control proportional valve is connected to a multi-channel electromagnetic valve through a flow measuring device; a pressure transmitter connected to the electric control device is provided between the multi-channel electromagnetic valve and the flow measuring device; the present invention can realize the function of outputting stable pressure airflow of a single channel or multiple channels, and can adjust the pressure of the output airflow in real time, effectively avoiding the downtime of the flow tester.

Description

Technical Field

[0001] The invention belongs to the technical field of flow testing devices, and in particular relates to a multi-channel gas flow automatic detection system. Background Art

[0002] At this stage, the country is vigorously developing the aviation industry, and the testing capabilities of aircraft components have also been relatively improved. In particular, as one of the important components of an aircraft, the pitot tube is composed of two concentric tubes, the inner tube is the total pressure tube, and the outer tube is the static pressure tube. When the aircraft flies forward, the airflow rushes into the pitot tube, and the sensor at the end of the tube will feel the impact of the airflow, that is, the dynamic pressure. The faster the aircraft flies, the greater the dynamic pressure.

[0003] The pitot tube is mainly used to measure the airflow pressure to get the airspeed. The static pressure measured by the pitot tube can also be used as a calculation parameter for the altimeter. The static pressure measured by the pitot tube can also be used to make a "vertical speed meter", that is, to measure the speed of the aircraft's altitude change. If the pitot tube is blocked, it will not be able to display the correct flight speed reading, which can cause a serious accident with the destruction of the aircraft and the loss of life.

[0004] In order to avoid the failure of the model pitot tube, the pitot tube needs to be tested for flow. At present, the method of measuring the pitot tube flow is generally through technicians with rich professional work experience. According to the working principle and characteristics of a single pitot tube, the atmospheric data tester is used to give a pressure value, which is output to the product through the flow meter, and the operator reads the flow meter pointer reading with the naked eye. This manual pitot tube testing method has poor reliability, low efficiency, long time, high skill requirements, and is not suitable for general staff. In addition, the traditional pitot tube measurement device does not have the function of multi-channel flow output, resulting in very low pitot tube detection efficiency. Summary of the invention

[0005] The purpose of the present invention is to provide a multi-channel gas flow automatic detection system, which can realize the function of single-channel or multi-channel stable output pressure airflow to test the flow of pitot tube, and can adjust the pressure of the output airflow in real time.

[0006] The present invention is achieved through the following technical solutions:

[0007] A multi-channel gas flow automatic detection system includes a pneumatic device and an electronic control device, wherein the pneumatic device includes an electronically controlled proportional valve connected to the electronic control device, a pressure reducing valve is provided at the air inlet end of the electronically controlled proportional valve, and an air outlet end of the electronically controlled proportional valve is connected to a multi-channel solenoid valve via a flow measuring device; a pressure transmitter connected to the electronic control device is provided between the multi-channel solenoid valve and the flow measuring device.

[0008] The pneumatic system is used to provide a certain pressure of airflow to the test product, and the electronic control device is used to adjust 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 to the air source, and the gas generated by the air source is reduced by the pressure reducing valve to the maximum pressure value that the electronic proportional valve can withstand. The electronic proportional valve outputs the gas to the multi-channel solenoid valve according to the set output ratio, and the multi-channel solenoid valve is used for single-channel or multi-channel airflow output. At the same time, the pressure transmitter detects the airflow pressure value output by the multi-channel solenoid valve to the product in real time, and converts the detected pressure value into an electrical signal and transmits it to the electronic control device. The electronic control device compares the actual output pressure of the multi-channel solenoid valve with the product demand pressure according to the received pressure electrical signal, and controls the output ratio of the electronic proportional valve based on the comparison result.

[0009] When the actual output pressure of the multi-channel solenoid valve is higher than the product demand pressure, the electronic control device feedback controls the electronically controlled proportional valve to reduce the output ratio, thereby reducing the output pressure of the multi-channel solenoid valve; when the actual output pressure of the multi-channel solenoid valve is lower than the product demand pressure, the electronic control device feedback controls the electronically controlled proportional valve to increase the output ratio, thereby increasing the output pressure of the multi-channel solenoid valve, until the output pressure of the multi-channel solenoid valve is equal to the product demand pressure. At this time, the electronic control device feedback controls the output ratio of the electronically controlled proportional valve to remain constant, thereby keeping the output pressure of the multi-channel solenoid valve constant.

[0010] In order to better realize the present invention, further, the electronic control device includes a PLC controller, a proportional valve controller connected to the electronically controlled proportional valve, a feedback control module and a switch output control module connected to the PLC controller, and the feedback control module is respectively connected to the pressure transmitter, the proportional valve controller, and an output channel of the multi-channel solenoid valve; the switch output control module is connected to the remaining output channels of the multi-channel solenoid valve.

[0011] In order to better realize the present invention, further, the multi-channel solenoid valve includes eight output channels, the switch output control module includes seven control interfaces, the seven control interfaces of the switch output control module are respectively connected to seven output channels of the multi-channel solenoid valve, and the feedback control module is connected to one of the output channels of the multi-channel solenoid valve.

[0012] In order to better realize the present invention, further, the feedback control module includes an AD feedback control module and a DA output control module, the transmission port of the AD feedback control module is connected to the pressure transmitter, and the feedback port of the AD feedback control module is connected to the proportional valve controller; the output control port of the DA output control module is connected to the proportional valve controller, and the switch quantity control port of the DA output control module is connected to an output channel of the multi-channel solenoid valve.

[0013] In order to better implement the present invention, further, a DC power supply connected to the pressure transmitter is included.

[0014] In order to better implement the present invention, further, the air inlet end of the pressure reducing valve is provided with a gas cylinder, and the air outlet end of the pressure reducing valve is provided with a pressure gauge.

[0015] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0016] (1) The present invention detects the output air flow pressure of the multi-channel solenoid valve in real time through a pressure transmitter, and at the same time, by presetting the product demand pressure in the PLC controller, the PLC controller can feedback control the output ratio of the electronically controlled proportional valve according to the difference between the pre-set product demand pressure and the output air flow pressure of the multi-channel solenoid valve, thereby adjusting the output air flow pressure of the multi-channel solenoid valve to match the product demand pressure, so that the entire air flow output pressure regulation is more efficient and accurate, and the air flow pressure regulation is more convenient and quick;

[0017] (2) The present invention sets a switch output control module, connects the corresponding output channels in the multi-channel solenoid valve through several switch output interfaces in the switch output control module, and directly connects the remaining output channel in the multi-channel solenoid valve through the switch output interface in the feedback control module; controls the on-off of several output channels in the multi-channel solenoid valve through several switch output interfaces in the switch output control module to achieve single-channel or multi-channel airflow output, and controls the on-off of one output channel in the multi-channel solenoid valve through the switch output interface in the feedback control module. Even if the switch output control module fails, it can still ensure that at least one output channel of the multi-channel solenoid valve maintains normal operation, effectively avoiding the entire flow tester from shutting down. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0019] Figure 2 It is a schematic diagram of the circuit structure of the electronic control device.

[0020] Among them: 1-electrically controlled proportional valve; 2-pressure reducing valve; 3-flow measuring device; 4-multi-channel solenoid valve; 5-pressure transmitter; 6-electrically controlled device; 7-gas cylinder; 61-PLC controller; 62-proportional valve controller; 63-feedback control module; 64-switch output control module; 65-DC power supply; 631-AD feedback control module; 632-DA output control module. DETAILED DESCRIPTION

[0021] Embodiment 1:

[0022] A multi-channel gas flow automatic detection system of this embodiment, such as Figure 1 As shown, it includes a pneumatic device and an electronic control device 6, the pneumatic device includes an electronically controlled proportional valve 1 connected to the electronic control device 6, the air inlet end of the electronically controlled proportional valve 1 is provided with a pressure reducing valve 2, the air outlet end of the electronically controlled proportional valve 1 is connected to a multi-channel solenoid valve 4 through a flow measuring device 3; a pressure transmitter 5 connected to the electronic control device 6 is provided between the multi-channel solenoid valve 4 and the flow measuring device 3.

[0023] The air inlet of the pressure reducing valve 2 is connected to the gas source. The gas of the gas source is reduced by the pressure reducing valve 2 to the maximum pressure value that the electric control proportional valve 1 can withstand. Then the electric control proportional valve 1 outputs a specific pressure of the gas flow to the multi-channel solenoid valve 4 according to the set output ratio. The multi-channel solenoid valve 4 includes several output channels. By controlling the opening and closing of several output channels, single-channel or multi-channel gas supply to the product can be achieved. At the same time, the gas flow entering the multi-channel solenoid valve 4 is detected in real time by the flow measuring device 3, and the input pressure of the multi-channel solenoid valve 4 is converted into an electrical signal by the pressure transmitter 5 and transmitted to the electronic control device 6. The electronic control device 6 and the electric control proportional valve 1, the electronic control device 6 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 supply pressure value. At this time, the electronic control device 6 controls the output ratio of the electric control proportional valve 1 to remain constant, thereby making the output pressure of the multi-channel solenoid valve 4 stable.

[0024] Embodiment 2:

[0025] This embodiment is further optimized on the basis of embodiment 1. Figure 2 As shown, the electronic control device 6 includes a PLC controller 61, a proportional valve controller 62 connected to the electronically controlled proportional valve 1, a feedback control module 63 connected to the PLC controller 61, and a switch output control module 64. The feedback control module 63 is respectively connected to the pressure transmitter 5, the proportional valve controller 62, and an output channel of the multi-channel solenoid valve 4; the switch output control module 64 is connected to the remaining output channels of the multi-channel solenoid valve 4.

[0026] The pressure transmitter 5 converts the input pressure of the multi-channel solenoid valve 4 into an electrical signal and transmits it to the feedback control module 63. The feedback control module 63 sends the pressure electrical signal to the PLC controller 61. The PLC controller 61 sends a control signal to the proportional valve controller 62 through the feedback control module 63 according to the output pressure value. The proportional valve controller 62 controls the output ratio of the electronically controlled proportional valve 1 in real time, thereby adjusting the output pressure of the multi-channel solenoid valve 4.

[0027] At the same time, a switch output control module 64 is provided corresponding to the N (N≥2) output channels of the multi-channel solenoid valve 4. The switch output control module 64 includes N-1 switch output interfaces, which are connected to the N-1 output channels of the multi-channel solenoid valve 4 to control the on-off of the output channels. At the same time, a switch output interface connected to the remaining output channels of the multi-channel solenoid valve 4 is provided in the feedback control module 63. The on-off of the N output channels of the multi-channel solenoid valve 4 is synchronously controlled by the switch output control module 64 and the feedback control module 63. Even if the switch output control module 64 fails, one of the output channels of the multi-channel solenoid valve 4 can be controlled by the feedback control module 63, thereby avoiding failure of the entire multi-channel flow tester.

[0028] Furthermore, the multi-channel solenoid valve 4 includes eight output channels, the switch output control module 64 includes seven control interfaces, the seven control interfaces of the switch output control module 64 are respectively connected to seven output channels of the multi-channel solenoid valve 4, and the feedback control module 63 is connected to one of the output channels of the multi-channel solenoid valve.

[0029] Furthermore, the PLC controller 61 is connected to the feedback control module 63 and the switch output control module 64 respectively through the RS485 interface.

[0030] Furthermore, the model of the switch output control module 64 is I-7067D, the model of the multi-channel solenoid 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.

[0031] The other parts of this embodiment are the same as those of Embodiment 1, and thus will not be described in detail.

[0032] Embodiment 3:

[0033] This embodiment is further optimized on the basis of the above embodiment 1 or 2. Figure 2 As shown, the feedback control module 63 includes an AD feedback control module 631 and a DA output control module 632. The transmission port of the AD feedback control module 631 is connected to the pressure transmitter 5, and the feedback port of the AD feedback control module 631 is connected to the proportional valve controller 62; the output control port of the DA output control module 632 is connected to the proportional valve controller 62, and the switch quantity control port of the DA output control module 632 is connected to an output channel of the multi-channel solenoid valve 4.

[0034] The DA output control module 632 provides an analog voltage to the electronically controlled proportional valve 1 through the proportional valve controller 62 according to the voltage characteristics of the electronically controlled proportional valve 1, thereby adjusting the output ratio of the electronically controlled proportional valve 1, and further adjusting the output pressure value of the multi-channel solenoid valve 4. At the same time, the switch 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.

[0035] The pressure value output by the multi-channel solenoid valve 4 is converted into an analog quantity through the pressure transmitter 5 and then transmitted to the PLC controller 61 through 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 boost signal to the electronically controlled proportional valve 1 through the AD feedback control module 631. At this time, the output ratio of the electronically controlled proportional valve 1 increases, thereby increasing the output pressure of the multi-channel solenoid valve 4; 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 depressurization signal to the electronically controlled proportional valve 1 through the AD feedback control module 631. At this time, the output ratio of the electronically controlled proportional valve 1 decreases, thereby reducing the output pressure of the multi-channel solenoid valve 4.

[0036] 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 stabilizing signal to the electronically controlled proportional valve 1 through the AD feedback control module 631. At this time, the output ratio of the electronically controlled proportional valve 1 remains constant, thereby keeping the output pressure of the multi-channel solenoid valve 4 constant.

[0037] 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.

[0038] The other parts of this embodiment are the same as those of the above-mentioned embodiment 1 or 2, and thus will not be described in detail.

[0039] Embodiment 4:

[0040] This embodiment is further optimized based on any one of the above embodiments 1-3. Figure 2 As shown, it also includes a DC power supply 65 connected to the pressure transmitter 5, and the DC power supply 65 supplies power to the pressure transmitter 5, the feedback control module 63, the switch output control module 64, and the PLC controller 61.

[0041] Furthermore, the DC power supply 65 is a 24V DC power supply 65.

[0042] Further, such as Figure 1 As shown, the air inlet end of the pressure reducing valve 2 is provided with a gas cylinder 7, and the gas cylinder 7 serves as a gas source to input an airflow with a pressure of 10Mpa to the pressure reducing valve 2. The air outlet end of the pressure reducing valve 2 is provided with a pressure gauge for real-time detection of the airflow pressure.

[0043] The other parts of this embodiment are the same as any one of the above embodiments 1-3, so they are not repeated here.

[0044] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. Any simple modification or equivalent change made to the above embodiment based on the technical essence of the present invention shall fall within the protection scope of the present invention.

Claims

1. A multi-channel gas flow automatic detection system, comprising a pneumatic device and an electric control device (6), characterized in that: The pneumatic device comprises an electrically controlled proportional valve (1) connected to an electrically controlled device (6); a pressure reducing valve (2) is provided at an air inlet of the electrically controlled proportional valve (1); an air outlet of the electrically controlled proportional valve (1) is connected to a multi-channel solenoid valve (4) via a flow measuring device (3); a pressure transmitter (5) connected to the electrically controlled device (6) is provided between the multi-channel solenoid valve (4) and the flow measuring device (3); the electrically controlled device (6) comprises a PLC controller (61), a proportional valve controller (62) connected to the electrically controlled proportional valve (1), and a pressure transmitter (5) connected to the multi-channel solenoid valve (4). A feedback control module (63) and a switch output control module (64) connected to a PLC controller (61), the feedback control module (63) being respectively connected to a pressure transmitter (5), a proportional valve controller (62), and an output channel of a multi-channel solenoid valve (4), the feedback control module (63) being provided with a switch output interface connected to the remaining output channels of the multi-channel solenoid valve (4); the switch output control module (64) being connected to the remaining output channels of the multi-channel solenoid valve (4); the multi-channel solenoid valve (4) comprising eight output channels, the switch output control module (64) comprising seven control interfaces, the seven control interfaces of the switch output control module (64) being respectively connected to seven output channels of the multi-channel solenoid valve (4), and the feedback control module (63) being connected to one output channel of the multi-channel solenoid valve (4); the feedback control module (63) comprising an AD feedback control module (631) and a DA output control module (632), the transmission port of the AD feedback control module (631) being connected to the pressure transmitter (5), the feedback port of the AD feedback control module (631) is connected to the proportional valve controller (62); the output control port of the DA output control module (632) is connected to the proportional valve controller (62), and the switch quantity control port of the DA output control module (632) is connected to an output channel of the multi-channel solenoid valve (4); and also includes a DC power supply (65) connected to the pressure transmitter (5); the air inlet end of the pressure reducing valve (2) is provided with a gas cylinder (7), and the air outlet end of the pressure reducing valve (2) is provided with a pressure gauge.

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