Patent ID: 11940353
Assignee: WUHAN UNIVERSITY OF TECHNOLOGY
Field: Measurement (Instruments)
Classification: CPC G | IPC G

Claim 5:
6. A test method based on the test device for an automatic pressure regulating valve of an EBS according to claim 5, comprising the following steps:
S1: assembly of the test device
arranging the frame under a bench panel;
laying an insulating pad on the bench panel to form an insulating operating desk;
fixing the on-off valve, the shut-off valves, the electro/pneumatic proportional valves, the brake chamber, the force sensor, and the automatic pressure regulating valve to be tested on the insulating operating desk through fasteners and the bracket;
sequentially connecting a pneumatic FRL unit, an air storage tank, the on-off valve, and a pressure reducing valve in series to form the pneumatic trunk;
connecting the air inlet of the pneumatic trunk to the air outlet of the air supply,
connecting the air inlet of the control air-in branch to the air outlet of the pneumatic trunk,
connecting the air outlet of the control air-in branch to the control air inlet of the automatic pressure regulating valve to be tested, and
connecting the first electro/pneumatic proportional valve in series in the control air-in branch;
connecting the air inlet of the first air-in branch to the air outlet of the pneumatic trunk,
connecting the air outlet of the first air-in branch to the first air inlet of the automatic pressure regulating valve to be tested, and
sequentially connecting the second electro/pneumatic proportional valve and the eighth shut-off valve in series in the first air-in branch;
connecting the air inlet of the first air exhaust branch to the first air exhaust port of the automatic pressure regulating valve to be tested,
connecting the air outlet of the first air exhaust branch to one side of the second shut-off valve, and
connecting the other side of the second shut-off valve to the silencer;
connecting the air inlet of the air-in branch to the air outlet of the pneumatic trunk,
connecting the air outlet of the air-in branch to the air inlet of the automatic pressure regulating valve to be tested, and
connecting the first shut-off valve in series in the air-in branch;
connecting the air inlet of the air-out branch to the air outlet of the automatic pressure regulating valve to be tested,
connecting the air outlet of the air-out branch to one side of the fifth shut-off valve, sequentially connecting the brake chamber and the third pressure sensor in series to the other side of the fifth shut-off valve, and
arranging the force sensor on the brake chamber;
arranging the first pressure sensor in the air-in chamber of the automatic pressure regulating valve to be tested;
arranging the second pressure sensor at the air outlet of the automatic pressure regulating valve to be tested;
sequentially connecting the sixth shut-off valve, the second flow sensor, and the seventh shut-off valve in series in the first air inlet flow test circuit, and connecting the first air inlet flow test circuit in parallel at two sides of the eighth shut-off valve;
sequentially connecting the third shut-off valve, the first flow sensor, and the fourth shut-off valve in series in the air inlet flow test circuit, and connecting the air inlet flow test circuit in parallel at two sides of the first shut-off valve;
connecting the signal input terminal of the filter circuit to the signal output terminal of each of the first pressure sensor, the second pressure sensor, the third pressure sensor, the first flow sensor, the second flow sensor, and the force sensor, and
connecting the signal output terminal of the filter circuit to the analog-to-digital conversion interface of the data acquisition circuit;
connecting the coil of the relay to the digital-to-analog conversion interface of the data acquisition circuit, and
connecting the contact of the relay to the controlled terminal of each of the first electro/pneumatic proportional valve, the second electro/pneumatic proportional valve, the first shut-off valve, the second shut-off valve, the third shut-off valve, the fourth shut-off valve, the fifth shut-off valve, the sixth shut-off valve, the seventh shut-off valve, the eighth shut-off valve, and the first air-in valve and the first air exhaust valve of the automatic pressure regulating valve to be tested;
connecting the signal transmit-receive terminal of the data acquisition circuit to the signal transmit-receive terminal of the control unit;
connecting the signal output terminal of the input unit to the signal input terminal of the control unit;
connecting the signal output terminal of the control unit to the signal input terminal of the output unit;
S2: draining condensated water everywhere, closing all shut-off valves to make an output pressure everywhere in the test device zero, and closing a throttle valve of the lubricator;
S3: starting the test device, and inputting control parameters into the control unit through the input unit, such that the control unit sends the control parameters to each component of the pneumatic circuit through the signal processing unit; and
S4: allowing each component of the pneumatic circuit to run according to the received control parameters, such that the automatic pressure regulating valve to be tested is subjected to a functional test, a static performance test, a dynamic performance test, an air tightness test, a leakage test, and a brake chamber braking force test sequentially;
wherein step S4 specifically comprises:
S41: the functional test: supplying air by the air supply to the pneumatic circuit, filtering the air through the pneumatic FRL unit to obtain clean compressed air, regulating an air supply pressure by the pressure reducing valve, opening all shut-off valves, and conducting an electronic failed brake test, an electronic brake test, and a coupled brake test sequentially;
S42: the static performance test: setting a target pressure by the control unit, testing according to step S41, and acquiring a pressure value of the first pressure sensor;
S43: the dynamic performance test: continuously changing the target pressure by the control unit, testing according to step S41, and acquiring a pressure value of the first pressure sensor;
S44: the air tightness test: supplying air by the air supply to the pneumatic circuit, filtering the air through the pneumatic FRL unit to obtain clean compressed air, and regulating an air supply pressure by the pressure reducing valve; opening the first shut-off valve, and supplying air to the automatic pressure regulating valve to be tested; after a target pressure is reached, keeping the pressure constant for 1 min and closing the control air inlet, the first air inlet, the first air exhaust port, the air inlet, and the air outlet of the automatic pressure regulating valve to be tested; and recording a pressure drop between the air outlet of the automatic pressure regulating valve to be tested and the control chamber within 5 min;
S45: the leakage test: subjecting the control chamber and the air-in chamber of the automatic pressure regulating valve to be tested to the leakage test sequentially; and
S46: the brake chamber braking force test: testing according to step S41, acquiring a force signal of the force sensor, and calculating and analyzing braking force change data of the automatic pressure regulating valve to be tested during a pressure regulating process;
wherein step S41 specifically comprises:
S411: the electronic failed brake test: sending a control signal by the control unit only to the first electro/pneumatic proportional valve, such that the first electro/pneumatic proportional valve regulates an outlet pressure of the automatic pressure regulating valve to be tested; and ventilating the control air inlet of the automatic pressure regulating valve to be tested, and acquiring pressure values of the first pressure sensor, the second pressure sensor, and the third pressure sensor by the control unit;
S412: the electronic brake test: sending a control signal only to the second electro/pneumatic proportional valve by the control unit, and ventilating the first air inlet of the automatic pressure regulating valve to be tested; and regulating an outlet pressure of the automatic pressure regulating valve to be tested by the first air-in valve and the first air exhaust valve of the automatic pressure regulating valve to be tested according to the control signal sent by the control unit, and acquiring pressure values of the first pressure sensor, the second pressure sensor, and the third pressure sensor by the control unit; and
S413: the coupled brake test: sending a control signal to both the first electro/pneumatic proportional valve and the second electro/pneumatic proportional valve by the control unit, such that the first electro/pneumatic proportional valve to ventilate the control air inlet and the first air inlet of the automatic pressure regulating valve to be tested; and regulating an outlet pressure of the automatic pressure regulating valve to be tested by the first air-in valve and the first air exhaust valve of the automatic pressure regulating valve to be tested according to the control signal sent by the control unit, and acquiring pressure values of the first pressure sensor, the second pressure sensor, and the third pressure sensor by the control unit
wherein step S45 specifically comprises:
S451: the leakage test of the control chamber: supplying air by the air supply to the pneumatic circuit, filtering the air through the pneumatic FRL unit to obtain clean compressed air, regulating an air supply pressure by the pressure reducing valve, and opening all shut-off valves; supplying air to the automatic pressure regulating valve to be tested, and after a target pressure is reached and the pressure is constant, closing the second shut-off valve and the eighth shut-off valve, such that the control chamber of the automatic pressure regulating valve to be tested is in a closed state but can continue to supply air; and acquiring a flow signal of the second flow sensor, which is a leakage of the control chamber of the automatic pressure regulating valve to be tested; and
S452: the leakage test of the air-in chamber: supplying air by the air supply to the pneumatic circuit, filtering the air through the pneumatic FRL unit to obtain clean compressed air, regulating an air supply pressure by the pressure reducing valve, and opening all shut-off valves; supplying air to the automatic pressure regulating valve to be tested, and after a target pressure is reached and the pressure is constant, closing the first shut-off valve and the fifth shut-off valve, such that a lower chamber of the automatic pressure regulating valve to be tested is in a closed state but can continue to supply air; and acquiring a flow signal of the first flow sensor, which is a leakage of the air-in chamber of the automatic pressure regulating valve to be tested.