Background
A large amount of fuel vapor is discharged from a fuel filling port in the automobile refueling process, and the emission of hydrocarbon pollutants is formed. A VII type test (namely an oiling pollutant emission test) is specially and newly added in the national VI emission standard to control oiling pollutant emission, and the oiling emission of a single vehicle is regulated to be lower than 0.05g/test, so that the existing national V fuel system is difficult to meet the requirements. The control to refuel the emission is at present tending to increase on-vehicle refuel vapor recovery unit, its theory of operation is in, the car refuels the in-process, the fuel constantly flows into the fuel tank, the liquid level risees the gas in the continuous extrusion fuel tank, the inside gas pressure of fuel tank risees, simultaneously because the volatility of petrol self and the flow of petrol, the inside a large amount of petrol vapour that can produce of fuel tank, the petrol vapour that produces in the fuel tank passes through the fuel tank gas outlet and gets into the activated carbon jar, by the activated carbon adsorption in the activated carbon jar, prevent that petrol vapour from leaking in the middle of the atmosphere, reduce hydrocarbon pollutant's emission. When the vehicle runs, the desorption electromagnetic valve on the desorption pipeline connecting the carbon canister and the engine is opened according to a preset control strategy, air is sucked from the atmosphere port of the carbon canister under the action of the vacuum pressure of the air inlet manifold, gas flows through the carbon canister and takes away oil gas adsorbed by activated carbon, flows out of the carbon canister through the desorption port, enters the air inlet manifold of the engine and finally enters the engine cylinder to be burnt, so that the activated carbon canister is desorbed and blown, and the adsorption working capacity is recovered again.
Under the prior art, for calibrating the carbon canister desorption control strategy, the carbon canister and the electromagnetic valve need to be installed on the whole vehicle, and the engine is allowed to run really to complete carbon canister desorption. Because it can't directly learn whether the canister desorption is accomplished to and when to accomplish not have monitoring device, can only judge whether the desorption satisfies the requirement through the adsorption effect of refueling pollutant emission test inspection canister, there are calibration steps loaded down with trivial details, experimental cycle length and the high problem of test cost.
Disclosure of Invention
In view of this, the utility model aims at providing a test device for the desorption control strategy calibration of an automobile activated carbon canister, which is matched with a controller, an oil tank, the activated carbon canister, an electromagnetic valve, a hydrocarbon concentration detector, a pressure stabilizing box and an adjustable pressure vacuum pump; the method can realize rapid and independent completion of the calibration of the desorption control strategy of the activated carbon tank, does not need to carry out an oiling pollutant emission test of the whole vehicle, and shortens the design development and desorption calibration periods of the activated carbon tank.
In order to achieve the above purpose, the technical scheme of the utility model is realized like this:
a test device for calibrating a desorption control strategy of an automobile activated carbon canister comprises a controller, an oil tank, the activated carbon canister and a hydrocarbon concentration detector; the air outlet of the oil tank is connected with the oil-gas inlet of the activated carbon tank, the desorption port of the activated carbon tank is connected with one end of the electromagnetic valve, the other end of the electromagnetic valve is connected with the inlet of the pressure stabilizing box, and the outlet of the pressure stabilizing box is connected with the extraction opening of the pressure-adjustable vacuum pump; the air inlet of the carbon-hydrogen concentration detector is connected with an atmospheric port of the activated carbon canister or an air outlet of the pressure-adjustable vacuum pump; a pressure stabilizing box pressure sensor is arranged in the pressure stabilizing box; the control end of the electromagnetic valve, the control end of the pressure-adjustable vacuum pump, the signal end of the pressure stabilizing box pressure sensor and the signal end of the hydrocarbon concentration detector are all connected with the controller.
Further, the controller is respectively connected with an ambient temperature sensor and an ambient pressure sensor.
In this embodiment, the controller may be a central controller or a PLC controller.
Furthermore, an oil filling pipe is arranged on the oil tank.
Compared with the prior art, the utility model relates to a test device that is used for car active carbon jar desorption control strategy to mark has following advantage:
the utility model relates to a test device that is used for car active carbon jar desorption control strategy to mark uses controller, oil tank, active carbon jar, solenoid valve, hydrocarbon concentration detector, surge tank and adjustable pressure vacuum pump in the cooperation, can realize independently accomplishing the demarcation of active carbon jar desorption control strategy fast, need not to carry out the refuel pollutant emission test of whole car, shortens the cycle that active carbon jar design development and desorption were markd.
Detailed Description
It should be noted that, in the present invention, the embodiments and features of the embodiments may be combined with each other without conflict.
In the description of the present invention, it is to be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like, indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are used merely for convenience of description and for simplicity of description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore, should not be construed as limiting the present invention. Furthermore, the terms "first", "second", etc. are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first," "second," etc. may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless otherwise specified.
In the description of the present invention, it is to be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present invention can be understood by those of ordinary skill in the art through specific situations.
The present invention will be described in detail below with reference to the accompanying drawings in conjunction with embodiments.
As shown in fig. 1-2, a test device for calibrating a desorption control strategy of an automobile activated carbon canister comprises a controller 1, an oil tank 6, an activated carbon canister 8 and a hydrocarbon concentration detector 14; an air outlet 4 of the oil tank 6 is connected with an oil gas inlet 7 of an activated carbon tank 8, a desorption port 10 of the activated carbon tank 8 is connected with one end of an electromagnetic valve 11, the other end of the electromagnetic valve 11 is connected with an inlet of a pressure stabilizing box 12, and an outlet of the pressure stabilizing box 12 is connected with an air suction port of an adjustable pressure vacuum pump 13; an air inlet of the hydrocarbon concentration detector 14 is connected with an atmosphere port 9 of the activated carbon canister 8 or an air outlet of the pressure-adjustable vacuum pump 13; a pressure stabilizing box pressure sensor 15 is arranged in the pressure stabilizing box 12; the control end of the electromagnetic valve 11, the control end of the adjustable pressure vacuum pump 13, the signal end of the pressure stabilizing box pressure sensor 15 and the signal end of the hydrocarbon concentration detector 14 are all connected with the controller 1.
Further, the controller 1 is connected to an ambient temperature sensor 2 and an ambient pressure sensor 3, respectively.
In this embodiment, the controller 1 may be a central controller or a PLC controller.
As shown in fig. 1-2, a filler pipe 5 is provided on the oil tank 6.
In this embodiment, the process for calibrating the desorption control strategy of the activated carbon canister of the vehicle is as follows:
if the activated carbon canister 8 is not used, the pretreatment of the canister is firstly carried out, and the pretreatment comprises complete adsorption and complete desorption of the canister:
and (3) complete adsorption of the carbon canister: the test device is connected as shown in fig. 1, at this time, the adjustable pressure vacuum pump 13 does not work, the electromagnetic valve 11 is closed, and the atmosphere port 9 of the activated carbon canister 8 is connected with the hydrocarbon concentration detector 14; firstly, carrying out the complete adsorption operation of the carbon canister: and continuously filling oil into the oil tank 6 at the oil filling temperature of 20 +/-1 ℃ and the oil filling speed of 37 +/-1L/min until the hydrocarbon concentration detector 14 detects that the hydrocarbon gas is discharged from the atmosphere port 9 of the activated carbon tank 8, and emptying the oil tank 6 after the activated carbon tank 8 is considered to be completely adsorbed.
And then continuing to perform complete desorption of the carbon canister: the test device is connected as shown in fig. 2, the hydrocarbon concentration detector 14 is connected with the air outlet of the adjustable pressure vacuum pump 13, the controller 1 is used for controlling the vacuum pressure of the adjustable pressure vacuum pump 13 to be 5kPa, the electromagnetic valve 11 is normally opened, and desorption operation is carried out until the hydrocarbon concentration detector 14 does not detect hydrocarbon gas.
After completing the charcoal jar preliminary treatment, begin activated carbon jar desorption control strategy and mark, if the charcoal jar used, then need not the preliminary treatment, can directly begin to mark:
step one, the oil tank 6 is filled with oil: the connection state of the test apparatus shown in fig. 2 is adopted to perform refueling operation of the fuel tank 6 according to the refueling requirements of the refueling pollutant emission test (VII test) in the limit of light automobile pollutant emission and the measurement method (sixth stage of china). Wherein the oiling temperature is 20 ℃ plus or minus 1 ℃, the oiling speed is 37L/min plus or minus 1L/min, the oiling amount is 85 percent plus or minus 0.5L, the volume of the oil tank is nominal, the adjustable pressure vacuum pump 13 does not work in the oiling operation, and the electromagnetic valve 11 is closed.
And secondly, the controller 1 controls the adjustable pressure vacuum pump 13 to be opened, the controller 1 controls the electromagnetic valve 11 to be opened and closed by taking the control strategy of the activated carbon canister 8 as a standard, the activated carbon canister 8 is calibrated, the hydrocarbon concentration in the gas discharged by the adjustable pressure vacuum pump 13 is detected by the hydrocarbon concentration detector 14, and whether the desorption of the activated carbon canister 8 is completed or not is judged. And if the desorption of the activated carbon canister 8 is not finished, modifying the control strategy of the activated carbon canister 8 in the controller 1, returning to the first step of oil tank 6 for refueling, and starting the circulation again until the desorbed gas detected by the hydrocarbon concentration detector 14 does not contain hydrocarbon gas, and finally finishing the calibration of the desorption control strategy of the activated carbon canister.
The above description is only a preferred embodiment of the present invention, and should not be taken as limiting the invention, and any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.