CN110793785A - Test device for calibrating desorption control strategy of automobile activated carbon canister - Google Patents

Abstract

The invention provides a test device for calibrating the desorption control strategy of an automobile activated carbon canister, which includes a controller, a fuel tank, an activated carbon canister and a hydrocarbon concentration detector; The desorption port of the tank is connected to one end of the solenoid valve, the other end of the solenoid valve is connected to the inlet of the surge tank, and the outlet of the surge tank is connected to the suction port of the adjustable pressure vacuum pump; the air inlet of the hydrocarbon concentration detector is connected to the atmosphere port of the activated carbon tank or Air outlet of an adjustable pressure vacuum pump. The invention is a test device for desorption control strategy calibration of an automobile activated carbon canister, which is used in conjunction with a controller, a fuel tank, an activated carbon canister, a solenoid valve, a hydrocarbon concentration detector, a voltage stabilizer box and an adjustable pressure vacuum pump; it can realize rapid and independent completion. The calibration of the desorption control strategy of the activated carbon canister does not need to carry out the refueling pollutant emission test of the whole vehicle, and shortens the cycle of the design and development of the activated carbon canister and the desorption calibration.

Description

A test device for desorption control strategy calibration of automobile activated carbon canister

technical field

The invention belongs to the technical field of automobiles, and in particular relates to a test device for calibrating a desorption control strategy of an automobile activated carbon canister.

Background technique

During the refueling process of the car, a large amount of fuel vapor will be discharged from the fuel filler, resulting in the emission of hydrocarbon pollutants. The National VI emission standard has specially added the Type VII test (ie, the fueling pollutant emission test) to control the fueling pollutant emissions, and stipulates that the single-vehicle fueling emissions are lower than 0.05g/test, and the existing National V fuel system is difficult to meet the requirements. The control of refueling emissions currently tends to increase the oil and gas recovery device for on-board refueling. Its working principle is that during the refueling process of the car, the fuel continuously flows into the fuel tank, the liquid level rises and the gas in the fuel tank is continuously squeezed, and the gas pressure inside the fuel tank rises. At the same time, due to the volatility of gasoline itself and the flow of gasoline, a large amount of gasoline vapor will be generated inside the fuel tank. The gasoline vapor generated in the fuel tank enters the activated carbon tank through the gas outlet of the fuel tank, and is adsorbed by the activated carbon in the activated carbon tank to prevent gasoline vapor from leaking into the atmosphere. , reduce the emission of hydrocarbon pollutants. When the vehicle is running, the desorption solenoid valve on the desorption pipeline connecting the carbon canister and the engine will be opened according to the preset control strategy. Under the action of the vacuum pressure of the intake manifold, the air will be sucked in from the air port of the carbon canister. When the gas flows through the carbon canister, it takes away the oil and gas adsorbed by the activated carbon, flows out of the carbon canister through the desorption port, enters the engine intake manifold, and finally enters the engine cylinder to be burned. In this way, the activated carbon canister is desorbed and purged, and the adsorption is restored again. Ability to work.

Under the existing technical conditions, for the calibration of the carbon canister desorption control strategy, it is necessary to install the carbon canister and the solenoid valve on the vehicle, and let the engine actually run to complete the carbon canister desorption. Since there is no monitoring device, it is impossible to directly know whether and when the desorption of the carbon canister is completed. Only by testing the adsorption effect of the carbon canister through the refueling pollutant emission test to judge whether the desorption meets the requirements, there are cumbersome calibration steps and tests. The problem of long cycle time and high test cost.

SUMMARY OF THE INVENTION

In view of this, the present invention aims to propose a test device for the calibration of the desorption control strategy of the automobile activated carbon canister. Pressure vacuum pump; can quickly and independently complete the calibration of the activated carbon canister desorption control strategy, without the need to carry out the vehicle refueling pollutant emission test, and shorten the cycle of activated carbon canister design and development and desorption calibration.

In order to achieve the above object, the technical scheme of the present invention is achieved in this way:

A test device for desorption control strategy calibration of an automobile activated carbon canister, comprising a controller, a fuel tank, an activated carbon canister and a hydrocarbon concentration detector; an air outlet of the fuel tank is connected to an oil and gas air inlet of the activated carbon canister, and the desorption of the activated carbon canister is The port is connected to one end of the solenoid valve, the other end of the solenoid valve is connected to the inlet of the stabilizing box, and the outlet of the stabilizing box is connected to the suction port of the adjustable pressure vacuum pump; the air inlet of the hydrocarbon concentration detector is connected to the atmospheric port of the activated carbon tank or the adjustable pressure vacuum pump The air outlet of the pressure stabilizer box is provided with a pressure stabilizer box pressure sensor; the control end of the solenoid valve, the control end of the adjustable pressure vacuum pump, the signal end of the pressure stabilizer box pressure sensor and the signal end of the hydrocarbon concentration detector are all connected with the controller.

Further, the controller is respectively connected to the ambient temperature sensor and the ambient pressure sensor.

In this embodiment, the controller may be a central computer or a PLC controller.

Further, a fueling pipe is provided on the fuel tank.

Compared with the prior art, a test device for desorption control strategy calibration of an automobile activated carbon canister of the present invention has the following advantages:

The present invention is a test device for desorption control strategy calibration of an automobile activated carbon canister, which can be used in conjunction with a controller, a fuel tank, an activated carbon canister, a solenoid valve, a hydrocarbon concentration detector, a voltage stabilizer box and an adjustable pressure vacuum pump to achieve rapid and independent control. To complete the calibration of the activated carbon canister desorption control strategy, there is no need to carry out the refueling pollutant emission test of the whole vehicle, and the cycle of activated carbon canister design and development and desorption calibration is shortened.

Description of drawings

The accompanying drawings constituting a part of the present invention are used to provide further understanding of the present invention, and the exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention.

In the attached image:

Fig. 1 is a kind of schematic diagram of carbon canister pretreatment state of a test device used for desorption control strategy calibration of automobile activated carbon canister according to an embodiment of the present invention;

2 is a schematic diagram of the desorption calibration state of a test device for the desorption control strategy calibration of an automobile activated carbon canister according to an embodiment of the present invention;

FIG. 3 is a schematic diagram of the use flow of a test device used for the calibration of the desorption control strategy of an automobile activated carbon canister according to an embodiment of the present invention.

Description of reference numbers:

1- Controller; 2- Ambient temperature sensor; 3- Ambient pressure sensor; 4- Air outlet; 5- Filling pipe; 6- Oil tank; 7- Oil and gas air inlet; 8- Activated carbon canister; Desorption port; 11-solenoid valve; 12-pressure-stabilizing box; 13-adjustable pressure vacuum pump; 14-hydrocarbon concentration detector; 15-pressure-stabilizing box pressure sensor.

Detailed ways

It should be noted that the embodiments of the present invention and the features of the embodiments may be combined with each other under the condition of no conflict.

In the description of the present invention, it should be understood that the terms "center", "portrait", "horizontal", "top", "bottom", "front", "rear", "left", "right", " The orientation or positional relationship indicated by vertical, horizontal, top, bottom, inner, outer, etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and The description is simplified rather than indicating or implying that the device or element referred to must have a particular orientation, be constructed and operate in a particular orientation, and therefore should not be construed as limiting the invention. In addition, the terms "first", "second", etc. are used for descriptive purposes only, and should not be construed as indicating or implying relative importance or implying the number of indicated technical features. Thus, a feature defined as "first", "second", etc., may expressly or implicitly include one or more of that feature. In the description of the present invention, unless otherwise specified, "plurality" means two or more.

In the description of the present invention, it should be noted that the terms "installed", "connected" and "connected" should be understood in a broad sense, unless otherwise expressly specified and limited, for example, it may be a fixed connection or a detachable connection Connection, or integral connection; can be mechanical connection, can also be electrical connection; can be directly connected, can also be indirectly connected through an intermediate medium, can be internal communication between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood through specific situations.

The present invention will be described in detail below with reference to the accompanying drawings and in conjunction with the embodiments.

As shown in Figure 1-2, a test device for desorption control strategy calibration of automobile activated carbon canister includes a controller 1, a fuel tank 6, an activated carbon canister 8 and a hydrocarbon concentration detector 14; the air outlet 4 of the fuel tank 6 is connected to the The oil and gas air inlet 7 of the activated carbon canister 8 is connected, the desorption port 10 of the activated carbon canister 8 is connected to one end of the solenoid valve 11, the other end of the solenoid valve 11 is connected to the inlet of the surge tank 12, and the outlet of the surge tank 12 is connected to the adjustable pressure vacuum pump 13 Air suction port; the air inlet of the hydrocarbon concentration detector 14 is connected to the atmospheric port 9 of the activated carbon canister 8 or the air outlet of the adjustable pressure vacuum pump 13; the surge tank 12 is provided with a surge tank pressure sensor 15; the control end of the solenoid valve 11 , The control end of the adjustable pressure vacuum pump 13 , the signal end of the pressure sensor 15 of the surge tank and the signal end of the hydrocarbon concentration detector 14 are all connected with the controller 1 .

Further, the controller 1 is respectively connected to the ambient temperature sensor 2 and the ambient pressure sensor 3 .

In this embodiment, the controller 1 may be a central computer or a PLC controller.

As shown in Fig. 1-2, the fuel tank 6 is provided with a fueling pipe 5.

In the present embodiment, the process of calibrating the desorption control strategy of the automobile activated carbon canister is as follows:

As shown in Figure 3, if the activated carbon canister 8 has not been used, the canister pretreatment should be performed first, including complete adsorption of the canister and complete desorption of the canister:

The carbon canister is completely adsorbed: the test device is connected as shown in Figure 1. At this time, the adjustable pressure vacuum pump 13 does not work, the solenoid valve 11 is closed, and the atmospheric port 9 of the activated carbon canister 8 is connected to the hydrocarbon concentration detector 14; Adsorption operation: continue to refuel the fuel tank 6 according to the refueling temperature of 20°C±1°C and the refueling rate of 37L/min±1L/min until the hydrocarbon concentration detector 14 detects that the hydrocarbon gas is discharged from the atmosphere port 9 of the activated carbon canister 8, which is regarded as The activated carbon canister 8 is completely adsorbed, and then the fuel tank 6 is emptied.

Continue to complete the desorption of the carbon canister: the test device is connected as shown in Figure 2, the hydrocarbon concentration detector 14 is connected to the air outlet of the adjustable pressure vacuum pump 13, the controller 1 is used to control the vacuum pressure of the adjustable pressure vacuum pump 13 at 5kPa, the solenoid valve 11 is normally open, and the desorption operation is performed until the hydrocarbon concentration detector 14 does not detect hydrocarbon gas.

After the carbon canister pretreatment is completed, start the desorption control strategy calibration of the activated carbon canister. If the carbon canister has been used, no pretreatment is required, and the calibration can be started directly:

The first step, refueling the fuel tank 6: using the connection state of the test device as shown in Figure 2, according to the "light-duty vehicle pollutant emission limit and measurement method (China's sixth stage)" in the refueling pollutant emission test (Type VII test) When refueling is required, perform refueling operation of fuel tank 6. The refueling temperature is 20°C±1°C, the refueling rate is 37L/min±1L/min, and the refueling volume is 85%±0.5L of the nominal fuel tank volume. During the refueling operation, the adjustable pressure vacuum pump 13 does not work, and the solenoid valve 11 is closed.

The second step, input the calibration control parameters: the common knowledge in the prior art: during the test driving process of the vehicle according to the refueling pollutant emission test (Type VII test), the engine intake manifold vacuum pressure change curve data is input to the controller. In 1, the adjustable pressure vacuum pump 13 is controlled to open according to this standard, and cooperates with the surge tank pressure sensor 15 to realize that the vacuum pressure in the surge tank 12 conforms to the input engine intake manifold vacuum pressure change curve.

Input the control strategy of the activated carbon canister 8 into the controller 1, use this as the standard to control the opening and closing of the solenoid valve 11, carry out the calibration of the activated carbon canister 8, and use the hydrocarbon concentration detector 14 to detect the adjustable pressure vacuum pump 13 to discharge carbon in the gas. The hydrogen concentration is used to judge whether the desorption of the activated carbon canister 8 is completed. If the desorption of the activated carbon canister 8 is not completed, modify the control strategy of the activated carbon canister 8 in the controller 1, return to the first step to refuel the fuel tank 6 and start the cycle again until the desorbed gas detected by the hydrocarbon concentration detector 14 does not contain Hydrocarbon gas, and finally complete the desorption control strategy calibration of the activated carbon canister.

In the above technical solution, the engine intake manifold vacuum pressure change curve data belongs to common knowledge in the art, and storing the pressure change curve and the canister desorption control strategy in the controller 1 is also a common technical means in the art.

The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention. within.

Claims (3)

1. The utility model provides a test device that is used for car active carbon jar desorption control strategy to markd which characterized in that: 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 the 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); the air inlet of the hydrocarbon concentration detector (14) is connected with the atmospheric port (9) of the activated carbon canister (8) or the air outlet of the adjustable pressure 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).

2. The test device for calibrating the desorption control strategy of the activated carbon canister of the automobile as claimed in claim 1, wherein: the controller (1) is respectively connected with the ambient temperature sensor (2) and the ambient pressure sensor (3).

3. The test device for calibrating the desorption control strategy of the activated carbon canister of the automobile as claimed in claim 1, wherein: an oil filling pipe (5) is arranged on the oil tank (6).

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