Compressed air quality detection unit and control method

Abstract

The invention discloses a compressed air quality detection unit and a control method, and belongs to the field of rail transit vehicle compressed air quality detection.The compressed air quality detection unit comprises an air path board, an overflow valve, a temperature and humidity sensor, a pressure reducing valve, an air inlet electromagnetic valve, a photoionization sensor and an exhaust electromagnetic valve, and the overflow valve, the temperature and humidity sensor, the pressure reducing valve, the air inlet electromagnetic valve, the photoionization sensor and the exhaust electromagnetic valve are installed on the air path board; wherein after entering a gas path in the gas path plate, gas of a gas source sequentially passes through the overflow valve, the temperature and humidity sensor, the pressure reducing valve, the gas inlet electromagnetic valve, the photoionization sensor and the gas exhaust electromagnetic valve and then is exhausted. The pressure reducing valve is arranged between the temperature and humidity sensor and the air inlet electromagnetic valve, the pressure of the main air source is effectively reduced, and therefore the beneficial effects that the service life of the photoionization sensor is prolonged, data detected by the detection device are more accurate, and the maintenance cost in the whole life cycle is reduced are achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of compressed air quality detection for rail transit vehicles, and in particular to a compressed air quality detection unit and a control method. Background Art

[0002] The traditional compressed air quality detection unit is a special device for detecting the temperature, humidity and oil and gas content of the compressed air in the vehicle's main air duct. Figure 1 As shown in the figure, it mainly consists of a sensor module, a main control module, a power module, a sealed housing, a hanging bracket, etc. It can monitor the temperature and humidity of the compressed air in the air source system in real time, and monitor the oil and gas content of the compressed air in the air source system in real time, ensuring that the air source system can provide clean, dry and stable compressed air for the power system, control system and braking system of subway vehicles;

[0003] The traditional installation method of the compressed air quality detection unit is to connect it to the main pipeline of the air source system through the G3 / 4 air line interface at both ends. The temperature, humidity, and oil and gas content of the compressed air passing through the detection unit are measured by two high-precision sensors (a humidity-sensitive capacitive temperature and humidity sensor and a photoionization sensor) on the sensor module within the detection unit. Airtightness is achieved by a sealing cover and a custom sealing ring. The sealing cover divides the detection unit into two upper and lower cavities. The lower cavity is connected to the vehicle's main air line, and the upper cavity is connected to the vehicle's DC110V power supply and communication port.

[0004] Since traditional compressed air quality detection units need to be installed in the main air pipe, they have to withstand relatively high air pressure (the air pressure in the normal main air pipe is 8bar-9.5bar) during the entire operation and parking of the vehicle. The photoionization sensor used to detect the oil and gas content in the detection unit is very sensitive to high-pressure air. Under its ideal working conditions, the pressure air should not be higher than 1bar. Its lifespan is 15 years when working in this suitable pressure environment. If the photoionization sensor works for a long time in an environment with a pressure higher than 1bar, its service life will be greatly shortened and it will need to be replaced after 3-4 years.

[0005] Therefore, in view of the above problems, it is necessary for the present invention to provide a compressed air quality detection unit with a long service life. Summary of the Invention

[0006] The purpose of the present invention is to overcome the defects of the prior art and provide a compressed air quality detection unit and a control method based on the compressed air quality detection unit, so as to increase the service life of the photoionization sensor and thereby reduce the maintenance cost of the compressed air quality detection unit throughout its life cycle.

[0007] In order to achieve the above object, the present invention provides the following technical solutions:

[0008] The present invention discloses a compressed air quality detection unit, comprising:

[0009] An air circuit board, an overflow valve installed on the air circuit board, a temperature and humidity sensor, a pressure reducing valve, an air intake solenoid valve, a photoionization sensor, and an exhaust solenoid valve;

[0010] Among them, the gas source gas enters the gas path in the gas path plate and then passes through the overflow valve, the temperature and humidity sensor, the pressure reducing valve, the air intake solenoid valve, the photoionization sensor, and the exhaust solenoid valve in sequence before being discharged.

[0011] Furthermore, a muffler is installed on the gas circuit board, and a muffler is installed on the gas circuit of the gas circuit board located at the exhaust end of the exhaust solenoid valve.

[0012] Furthermore, the minimum pressure valve setting value of the overflow valve is 500Kpa.

[0013] Furthermore, the pressure setting value of the pressure reducing valve is not greater than the working calibration pressure value that the photoionization sensor can withstand.

[0014] Furthermore, it also includes a box that can be installed on a branch of the vehicle's main air main line through a tee, the air circuit plate is integrated in the box, and a shut-off valve is provided at the air inlet of the branch located at the compressed air quality detection unit.

[0015] Invent a control method based on the above-mentioned compressed air quality detection unit:

[0016] When the main air source always supplies air to the air quality detection unit, during detection, the exhaust solenoid valve is energized and opened, and then the intake solenoid valve is energized and opened, and the gas is discharged through the air path in the air path plate. Then, the exhaust solenoid valve loses power and closes, and the photoionization sensor is energized and detects the oil content value of the gas. Then, the intake solenoid valve loses power and closes, and the photoionization sensor loses power, the sensor is closed, and the detection ends.

[0017] Furthermore, the temperature and humidity sensor is installed before the pressure reducing valve, and is continuously powered when there is no need for pressure reduction, so as to continuously detect data.

[0018] In the above technical solution, the present invention provides a compressed air quality detection unit, which has the following beneficial effects compared with the prior art:

[0019] 1. This detection unit is equipped with a relief valve, also known as the minimum pressure valve, on the air inlet pipe of the temperature and humidity sensor. When a leak occurs in the detection unit, causing the pressure value of the main air line to fall below the set value of the relief valve, the air supply line of the detection unit will be automatically cut off, thereby ensuring the total air pressure in the main air line and avoiding affecting the normal operation of the brake system.

[0020] 2. This detection unit is equipped with an intake solenoid valve and an exhaust solenoid valve at the intake and exhaust ends of the photoionization sensor respectively. By adjusting the control logic, the intake solenoid valve and the exhaust solenoid valve can be controlled in combination, thereby adjusting the working rate of the air compressor and suppressing the occurrence of oil emulsification.

[0021] 3. This detection unit is equipped with a pressure reducing valve between the temperature and humidity sensor and the air intake solenoid valve, which effectively reduces the pressure of the main air source, thereby increasing the service life of the photoionization sensor, making the data detected by the detection device more accurate, and reducing maintenance costs throughout the entire life cycle;

[0022] 4. When assembling this detection unit, it is installed on the branch of the main air pipe through a three-way connection. This does not affect the normal operation of the main air pipe and can also detect the quality parameters of the compressed air. At the same time, a shut-off valve is provided at the air inlet of the detection unit, which can be used to open and close the air at any time. Even if the device fails or is disassembled for maintenance, as well as subsequent detection and calibration, it will not affect the operation of the vehicle, and can ensure the safe driving of the vehicle.

[0023] In the above technical solution, the present invention provides a control method based on the above-mentioned compressed air quality detection unit, which has the same beneficial effects as the above-mentioned compressed air quality detection unit and will not be described in detail here. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments described in the present invention. For ordinary technicians in this field, other drawings can also be obtained based on these drawings.

[0025] Figure 1 It is a cross-sectional view of a compressed air quality detection unit in the prior art;

[0026] Figure 2 This is a gas circuit principle diagram of a compressed air quality detection unit disclosed in the present invention;

[0027] Figure 3 This is an outline diagram of a compressed air quality detection unit disclosed in the present invention.

[0028] Description of reference numerals:

[0029] 100. Compressed air quality detection unit; 200. Main line;

[0030] 1. Overflow valve; 2. Temperature and humidity sensor; 3. Pressure reducing valve; 4. Intake solenoid valve; 5. Photoionization sensor; 6. Exhaust solenoid valve; 7. Muffler; 8. Box; 9. Shut-off valve.

[0031] Prior art reference numerals:

[0032] 1′, lifting bracket; 2′, lower cavity shell; 3′, sensor module; 4′, sealing cover; 5′, power module; 6′, main control module; 7′, upper cavity shell. DETAILED DESCRIPTION

[0033] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings.

[0034] Figure 2 The compressed air quality detection unit 100 disclosed in the present invention:

[0035] The compressed air quality detection unit 100 is used to detect the gas quality after the air is compressed by the air compressor on the vehicle. It is installed on the branch of the main air pipe 200 through a three-way connection. It does not affect the normal operation of the main air pipe 200 and can also detect the quality parameters of the compressed air. In addition, the branch is provided with a cut-off valve 9 at the air inlet of the compressed air quality detection unit 100, which can open and close the air at any time. Even if the compressed air quality detection unit 100 fails or is disassembled for maintenance, as well as subsequent detection and calibration, it will not affect the operation of the vehicle, and the safe driving of the vehicle can be guaranteed.

[0036] The compressed air quality detection unit 100 includes an air manifold, a relief valve 1 mounted on the air manifold, a temperature and humidity sensor 2, a pressure reducing valve 3, an air intake solenoid valve 4, a photoionization sensor 5, an exhaust solenoid valve 6, a muffler 7, and a box 8;

[0037] Among them, the gas source gas enters the gas path in the gas circuit board and passes through the overflow valve 1, temperature and humidity sensor 2, pressure reducing valve 3, intake solenoid valve 4, photoionization sensor 5, exhaust solenoid valve 6 in sequence before being discharged.

[0038] Specifically, the compressed air quality detection unit 100 adjusts the gas circuit principle and adopts an integrated structure. All valve bodies are installed on the gas circuit board and finally integrated into a control box.

[0039] The principle of the gas circuit is to pass the gas source gas into the box body 8 of the control box, and the gas first enters the overflow valve 1 through the internal gas circuit of the gas circuit board. The minimum pressure valve setting value of the overflow valve 1 is 500Kpa. Before entering the cavity of the temperature and humidity sensor 2, the temperature and humidity of the gas are detected, and then the gas enters the pressure reducing valve 3. The pressure setting value of the pressure reducing valve 3 is not greater than the working calibration pressure value that the photoionization sensor 5 can withstand. Specifically, the setting value of the pressure reducing valve 3 is 0.1Mpa. After entering the air intake solenoid valve 4, the gas passes through the air intake solenoid valve 4 and enters the cavity of the photoionization sensor 5 to detect the oil content of the gas. Finally, the gas enters the exhaust solenoid valve 6 and is discharged through the muffler 7.

[0040] The main air flow line 200 of the vehicle air supply system is combined with the above-mentioned compressed air quality detection unit 100 to effectively extend the life of the photoionization sensor 5 and adjust the working rate of the air compressor. The control method of the compressed air quality detection unit 100 is as follows:

[0041] The vehicle air supply system is set to detect the gas once every 60 minutes (this time can be adjusted according to the oil emulsification state of the oil air compressor). The working logic is that when the main air source always supplies air to the air quality detection unit through the main line 200, during the detection, the exhaust solenoid valve 6 is energized and the solenoid valve is opened. Then the intake solenoid valve 4 is energized, the solenoid valve is opened, and the gas is discharged through the internal air path. The exhaust time is 30 seconds (this time can be adjusted according to the oil emulsification state of the oil air compressor). Then the exhaust solenoid valve 6 is de-energized and the solenoid valve is closed. After the photoionization sensor 5 is energized for 30 seconds, the sensor detects the oil content of the gas. Then the intake solenoid valve 4 is de-energized, the solenoid valve is closed, the photoionization sensor 5 is de-energized, the sensor is closed, and the detection ends. The cycle is repeated every 60 minutes. The temperature and humidity sensor 2 is installed before the pressure reducing valve 3. It is continuously energized and continuously detects data without pressure reduction.

[0042] In the above technical solution, the compressed air quality detection unit 100 provided by the present invention effectively improves the service life of the photoionization sensor, thereby reducing the maintenance cost of the compressed air quality detection unit 100 during the entire life cycle, and the compressed air quality detection unit 100 is also integrated with a working rate adjustment function, which can improve the working rate of the oil air compressor by regularly discharging compressed air from the main air duct and regularly starting the oil air compressor, thereby reducing the probability of oil emulsification in the oil air compressor.

[0043] The above description is merely illustrative of certain exemplary embodiments of the present invention. It goes without saying that those skilled in the art will be able to modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the above drawings and description are illustrative in nature and should not be construed as limiting the scope of protection of the claims.

Claims

1. A compressed air quality detection unit (100), characterized in that: include: An air circuit board, an overflow valve (1) mounted on the air circuit board, a temperature and humidity sensor (2), a pressure reducing valve (3), an air intake solenoid valve (4), a photoionization sensor (5), and an air exhaust solenoid valve (6); The gas source gas enters the gas path in the gas path plate and then passes through the overflow valve (1), the temperature and humidity sensor (2), the pressure reducing valve (3), the air intake solenoid valve (4), the photoionization sensor (5), and the exhaust solenoid valve (6) in sequence before being discharged.

2. The compressed air quality detection unit (100) according to claim 1, characterized in that; A muffler (7) is also installed on the gas circuit board, and the muffler (7) is installed on the gas circuit of the gas circuit board located at the exhaust end of the exhaust solenoid valve (6).

3. The compressed air quality detection unit (100) according to claim 1, characterized in that ； The minimum pressure valve setting value of the overflow valve (1) is 500Kpa.

4. The compressed air quality detection unit (100) according to claim 1, characterized in that: The pressure setting value of the pressure reducing valve (3) is no greater than the working calibrated pressure value that the photoionization sensor (5) can withstand.

5. The compressed air quality detection unit (100) according to claim 1, characterized in that ； It also includes a box (8) that can be installed on a branch of the vehicle's main air main line (200) through a tee, the air circuit board being integrated into the box (8), and a shutoff valve (9) being provided at the air inlet of the branch located at the compressed air quality detection unit (100).

6. A control method based on the compressed air quality detection unit (100) according to any one of claims 1 to 5: When the main gas source always supplies gas to the air quality detection unit, during detection, the exhaust solenoid valve (6) is energized and opened, and then the intake solenoid valve (4) is energized and opened, and the gas is discharged through the gas path in the gas path plate. Then, the exhaust solenoid valve (6) is de-energized and closed, and the photoionization sensor (5) is energized and detects the oil content value of the gas. Then, the intake solenoid valve (4) is de-energized and closed, and the photoionization sensor (5) is de-energized, the sensor is closed, and the detection ends.

7. The control method of the compressed air quality detection unit (100) according to claim 6, characterized in that ； The temperature and humidity sensor (2) is installed before the pressure reducing valve (3) and is continuously powered and continuously detects data when pressure reduction is not required.

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