Device and method for testing oil gas emission in gasoline car refueling process

Abstract

The invention relates to the technical field of testing devices, in particular to a device and method for testing the oil gas emission amount in the gasoline car refueling process. According to the technical scheme, the device comprises a vacuum pump and further comprises a pair of activated carbon adsorption pipes, a first connector is fixedly installed at one end of each activated carbon adsorption pipe, one end of each first connector is connected with the vacuum pump, and a second connector is fixedly installed at the other end of each activated carbon adsorption pipe; one end of the second connector is fixedly provided with a flow control valve, one end of the flow control valve is communicated with a gas flow meter, and one end of the gas flow meter is communicated with a special oil gas collecting cover. Accurate capture and quantitative calculation of oil gas emission in the whole refueling process are achieved, the accuracy and reliability of detection data are improved, maintenance is convenient, operation is convenient, and assembling is convenient.

Description

Technical Field

[0001] This invention relates to the field of testing equipment technology, and in particular to a device and method for testing the amount of fuel gas emitted during the refueling process of a gasoline vehicle. Background Technology

[0002] With the continuous growth of car ownership, emissions from gasoline vehicle refueling have become a significant source of air pollution. Volatile organic compounds (VOCs) such as benzene, toluene, and xylene contained in these gases not only harm human health but also participate in photochemical reactions, exacerbating environmental problems such as smog and ozone pollution. Therefore, effective control of gasoline emissions during refueling has become a critical requirement in the field of ecological and environmental protection.

[0003] Currently, to reduce oil and gas leakage during refueling, Beijing and other cities have begun to promote ORVR (On-Board Vapor Recovery) compatible fuel nozzles. The emission reduction effect of these nozzles urgently needs to be evaluated through accurate testing data to support the implementation and optimization of relevant environmental protection policies. However, existing gasoline vehicle refueling emission testing technologies still have many shortcomings and cannot meet practical application needs. Existing testing equipment is generally bulky and cumbersome, lacking mobility and flexibility, and cannot quickly adapt to diverse testing scenarios at different gas stations and pump locations. This limits the coverage of testing work and makes it difficult to achieve large-scale, multi-point emission reduction effect verification. Traditional testing devices have complex operating procedures, requiring high levels of professional skills from operators, which not only prolongs on-site testing time but also easily leads to data distortion due to improper operation, hindering efficient on-site testing. Existing testing technologies are mostly instantaneous detection modes, lacking cumulative measurement functions for oil and gas emissions throughout the entire refueling process, and are difficult to eliminate ambient air background interference, resulting in insufficient detection accuracy and an inability to accurately reflect the oil and gas emission patterns throughout the refueling cycle, making it difficult to support ORVR. The evaluation of the emission reduction effect of compatible fuel nozzles provides reliable data support. In existing testing devices, the adsorbents (such as activated carbon) used to adsorb oil and gas usually need to be replaced as a whole after adsorption saturation, which not only increases the cost of consumables for testing but may also cause resource waste. At the same time, the adsorbent is prone to agglomeration during long-term use, resulting in a reduction in adsorption area, which in turn reduces the oil and gas adsorption efficiency and the accuracy of detection data. Existing devices lack effective solutions for adsorbent regeneration and reuse and anti-agglomeration, which further limits the practicality and economy of the testing device. Therefore, this application proposes a testing device and method for oil and gas emissions during the refueling process of gasoline vehicles. Summary of the Invention

[0004] The purpose of this invention is to address the problems of cumbersome operation and inaccurate detection results in the prior art by proposing a device and method for testing the amount of gasoline emissions during the refueling process of a gasoline vehicle.

[0005] In a first aspect, the present invention provides a device for testing the amount of oil and gas emissions during the refueling process of a gasoline vehicle, including a vacuum pump and a pair of activated carbon adsorption tubes. A first connector is fixedly installed at one end of each activated carbon adsorption tube, and one end of the first connector is connected to the vacuum pump. A second connector is fixedly installed at the other end of each activated carbon adsorption tube, and a flow control valve is fixedly installed at one end of the second connector. One end of the flow control valve is connected to a gas flow meter, and one end of the gas flow meter is connected to a dedicated oil and gas collection hood. An auxiliary mechanism for regenerating and reusing saturated adsorbent is provided inside each activated carbon adsorption tube, and a dispersing mechanism is provided inside each activated carbon adsorption tube to prevent adsorbent from clumping.

[0006] Optionally, the auxiliary mechanism includes a third connector fixedly installed at one end of the activated carbon adsorption tube, a first connecting pipe fixedly installed on the third connector, a heating block fixedly installed on the first connecting pipe, an air pump fixedly installed at one end of the heating block, an air storage tank fixedly installed at one end of the air pump, a fourth connector fixedly installed at the other end of the activated carbon adsorption tube, a second connecting pipe fixedly installed at one end of the fourth connector, a cooling pipe fixedly installed at one end of the second connecting pipe, a spiral tube fixedly installed at one end of the cooling pipe, a collection trough fixedly installed at one end of the spiral tube, and an air outlet opened on the collection trough.

[0007] Optionally, the dispersing mechanism includes a toothed disc fixedly installed inside the activated carbon adsorption tube. A base is rotatably installed on the bottom of the toothed disc, and multiple first gears are rotatably installed on the base. The first gears mesh with the toothed disc. A second gear is rotatably installed on the bottom of the base and is fixedly connected to the first gear. A third gear is rotatably installed on the bottom of the base and meshes with the second gear. A connecting plate is fixedly installed on the bottom of the third gear, and a stirring rod is fixedly installed at one end of the connecting plate. Multiple stirring blocks are fixedly installed on the stirring rod.

[0008] Optionally, a connecting shaft is rotatably installed inside the activated carbon adsorption tube, and one end of the connecting shaft is fixedly connected to the base.

[0009] Optionally, a motor is fixedly installed on the activated carbon adsorption tube, and the output shaft of the motor is fixedly connected to the connecting shaft.

[0010] Optionally, the gear plate has a mounting hole, and the connecting shaft is located inside the mounting hole.

[0011] Optionally, a fixing rod is fixedly installed on the toothed disc, and one end of the fixing rod is fixedly connected to the inner wall of the activated carbon adsorption tube.

[0012] Optionally, a first electronic valve is fixedly installed on the first connector, and a second electronic valve is fixedly installed on the second connector.

[0013] Optionally, a third electronic valve is fixedly installed on the third connector, and a fourth electronic valve is fixedly installed on the fourth connector.

[0014] Secondly, this invention provides a method for testing the amount of gasoline vapor emissions during the refueling process of a gasoline vehicle, including a gasoline vapor emission testing device as described in the first aspect. Two dedicated vapor collection hoods are respectively placed over the outer side of the test fuel nozzle's vapor collection hood, ensuring a tight fit. The mass of the activated carbon adsorption tube in the vapor collection branch is weighed and recorded as m1, and the mass of the activated carbon adsorption tube in the air comparison branch is recorded as mg1. The vacuum pump is started to introduce nitrogen, generating a stable vacuum negative pressure. Two gas flow meters are turned on, and the corresponding flow control valves are adjusted to ensure that the gas flow rates in the vapor collection branch and the air comparison branch are consistent and precisely matched with the preset refueling flow rate of the fuel nozzle under test. The refueling operation is then initiated. During the refueling process, oil and gas enter the oil and gas collection branch through the dedicated oil and gas collection hood and are adsorbed by the activated carbon adsorption tube in the branch. At the same time, the air comparison branch collects ambient air. After refueling is completed, the device is turned off, and the mass of the activated carbon adsorption tube in the oil and gas collection branch is weighed using an electronic balance and recorded as m2, and the mass of the activated carbon adsorption tube in the air comparison branch is recorded as mk2. The mass change of the activated carbon adsorption tube in the oil and gas collection branch is calculated according to the formula Δm=m2-m1, and the mass change of the activated carbon adsorption tube in the air comparison branch is calculated according to the formula Δmk=mk2-mk1. Then, the actual oil and gas emission amount is calculated by subtracting the background interference of ambient air using the formula Δm-Δmk, and the accurate oil and gas emission value is obtained.

[0015] Compared with the prior art, the present invention has the following beneficial technical effects: This invention involves placing two dedicated oil and gas collection hoods over the outside of the test oil gun's gas collection hood, ensuring a tight fit. The mass of the activated carbon adsorption tube in the oil and gas collection branch is weighed and recorded as m1, and the mass of the activated carbon adsorption tube in the air comparison branch is recorded as mg1. The vacuum pump is started to introduce nitrogen, generating a stable negative vacuum pressure. Two gas flow meters are turned on, and the corresponding flow control valves are adjusted to ensure that the gas flow rates in the oil and gas collection branch and the air comparison branch are consistent and precisely matched with the preset refueling flow rate of the test oil gun. The refueling operation is then initiated. Throughout the refueling process, oil and gas enter the oil and gas collection hood through the dedicated oil and gas collection hoods. The activated carbon adsorption tube in the oil and gas collection branch is adsorbed by the activated carbon adsorption tube in that branch. At the same time, the ambient air is collected in the air comparison branch. After refueling is completed, the device is turned off. The mass of the activated carbon adsorption tube in the oil and gas collection branch is weighed using an electronic balance and recorded as m2, and the mass of the activated carbon adsorption tube in the air comparison branch is recorded as mk2. The mass change of the activated carbon adsorption tube in the oil and gas collection branch is calculated according to the formula Δm=m2-m1. The mass change of the activated carbon adsorption tube in the air comparison branch is calculated according to the formula Δmk=mk2-mk1. Then, the actual oil and gas emission is calculated using the formula Δm-Δmk. After deducting the background interference of ambient air, the accurate oil and gas emission value is obtained.

[0016] Furthermore, by closing the first and second electronic valves and opening the third and fourth electronic valves, the air pump and heating block are activated. The air pump delivers heated nitrogen gas to the activated carbon adsorption tube to heat the activated carbon inside. Heating causes the oil and gas molecules adsorbed on the surface of the activated carbon to gain energy and detach from the adsorption sites. Nitrogen gas is continuously purged, and the desorbed oil and gas are discharged from the fourth connector and then transported to the cooling pipe through the second connector. As the temperature decreases, the oil and gas are converted into liquid gasoline and flow into the collection tank for collection, thus realizing the regeneration and reuse of activated carbon.

[0017] Furthermore, by rotating the base, the base drives the first gear to rotate, the first gear drives the second gear to rotate, the second gear drives the third gear to rotate, and the third gear drives the connecting plate to rotate, which in turn drives the stirring rod to rotate. The stirring rod can both rotate on its own axis and revolve around the first gear, so that the stirring block can fully disperse the activated carbon inside, preventing the activated carbon from clumping and reducing the adsorption effect. At the same time, in the regeneration and reuse stage of activated carbon, dispersing helps hot gas to contact the activated carbon better, improves the oil and gas discharge efficiency, and improves the desorption effect.

[0018] This invention enables precise capture and quantitative calculation of oil and gas emissions throughout the refueling process, improving the accuracy and reliability of detection data, and is easy to maintain, operate, and assemble. Attached Figure Description

[0019] Figure 1 A schematic diagram of a device for testing the amount of fuel gas emissions during the refueling process of a gasoline vehicle. Figure 2 Schematic diagram of activated carbon adsorption tube structure Figure 1 ; Figure 3 Schematic diagram of activated carbon adsorption tube structure Figure 2 ; Figure 4 Schematic diagram of activated carbon adsorption tube structure Figure 3 ; Figure 5 A schematic diagram of the gear disc, the first gear, and the connecting shaft; Figure 6 This is a schematic diagram of the second gear, the third gear, and the connecting plate.

[0020] Reference numerals: 1. Vacuum pump; 2. Gas flow meter; 3. Activated carbon adsorption tube; 4. Flow control valve; 5. Special oil and gas collection hood; 6. Second connector; 7. Third connector; 8. Fourth connector; 9. First electronic valve; 10. Second electronic valve; 11. Third electronic valve; 12. Fourth electronic valve; 13. Gas storage tank; 14. Gas pump; 15. Heating block; 16. First connecting pipe; 17. Second connecting pipe; 18. Cooling pipe; 19. Spiral tube; 20. Gas outlet; 21. Collection tank; 22. Fixing rod; 23. Stirring rod; 24. Stirring block; 25. Gear disc; 26. Connecting shaft; 27. Base; 28. First gear; 29. ​​Second gear; 30. Connecting plate; 31. Third gear; 32. Mounting hole; 33. First connector; 34. Motor. Detailed Implementation

[0021] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0022] The components of the embodiments of the invention described and shown in the accompanying drawings can typically be arranged and designed in a variety of different configurations. Therefore, the following detailed description of the embodiments of the invention provided in the drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention.

[0023] Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0024] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0025] It should be noted that the terms "comprising," "including," or any other variations thereof are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiments or examples. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0026] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0027] Example 1 like Figure 1-2As shown, the present invention proposes a gasoline vehicle refueling process fuel vapor emission testing device, which includes a vacuum pump 1. By introducing nitrogen gas to generate a vacuum negative pressure, it drives the gas flow in the pipeline, providing continuous power for fuel vapor collection. No external power supply is required, ensuring safety and explosion prevention. It also includes a pair of activated carbon adsorption tubes 3. Utilizing the high adsorption performance of activated carbon, it captures and stores the fuel vapor emitted during refueling. The amount of fuel vapor adsorbed is calculated by the change in mass before and after refueling. A first connector 33 is fixedly installed at one end of the activated carbon adsorption tube 3, and one end of the first connector 33 is connected to the vacuum pump 1. A second connector 6 is fixedly installed at the other end of the activated carbon adsorption tube 3. A flow control valve 4 is fixedly installed at one end of the second connector 6 to control the fuel vapor collection pipeline relative to air. The gas flow rate in the pipeline ensures that the oil and gas collection flow rate is perfectly matched with the refueling flow rate, preventing oil and gas from escaping or excessive air intake. One end of the flow control valve 4 is connected to a gas flow meter 2, which has real-time monitoring and cumulative metering functions, accurately recording the instantaneous flow rate and total flow rate of the recovered gas, providing data support for flow regulation, and ensuring the effectiveness of collection. One end of the gas flow meter 2 is connected to a dedicated oil and gas collection hood 5, which adopts a close-fitting design and is installed on the outside of the gasoline refueling nozzle's gas collection hood to form a sealed collection space, comprehensively capturing any oil and gas that may escape during the refueling process and preventing leakage. The activated carbon adsorption tube 3 is equipped with an auxiliary mechanism for regenerating and reusing the saturated adsorbent, and a mechanism to prevent the adsorbent from clumping is also provided inside the activated carbon adsorption tube 3.

[0028] like Figure 2-3As shown, the auxiliary mechanism includes a third connector 7 fixedly installed at one end of the activated carbon adsorption tube 3, a first connecting pipe 16 fixedly installed on the third connector 7, a heating block 15 fixedly installed on the first connecting pipe 16, the heating block 15 having a built-in heating resistor, an air pump 14 fixedly installed at one end of the heating block 15, an air storage tank 13 fixedly installed at one end of the air pump 14, the air storage tank 13 storing nitrogen gas, a fourth connector 8 fixedly installed at the other end of the activated carbon adsorption tube 3, a second connecting pipe 17 fixedly installed at one end of the fourth connector 8, a cooling pipe 18 fixedly installed at one end of the second connecting pipe 17, a spiral tube 19 fixedly installed at one end of the cooling pipe 18, a collection tank 21 fixedly installed at one end of the spiral tube 19, an air outlet 20 opened on the collection tank 21, a first electronic valve 9 fixedly installed on the first connector 33, and a second... A second electronic valve 10 is fixedly installed on connector 6, a third electronic valve 11 is fixedly installed on connector 7, and a fourth electronic valve 12 is fixedly installed on connector 8. When the activated carbon in the activated carbon adsorption tube 3 is saturated, the first electronic valve 9 and the second electronic valve 10 are closed, and the third electronic valve 11 and the fourth electronic valve 12 are opened. The air pump 14 and the heating block 15 are started. The air pump 14 delivers heated nitrogen to the activated carbon adsorption tube 3 to heat the activated carbon inside. Heating causes the oil and gas molecules adsorbed on the surface of the activated carbon to gain energy and detach from the adsorption sites. The nitrogen continues to purge, and the desorbed oil and gas are discharged from connector 8 and then transported to cooling pipe 18 through second connector 17. As the temperature decreases, the oil and gas are converted into liquid gasoline and flow into collection tank 21 for collection. The nitrogen is discharged and will not pollute the air.

[0029] Example 2 like Figure 3 , Figure 4 , Figure 5 and Figure 6As shown, the dispersing mechanism includes a toothed disc 25 fixedly installed inside the activated carbon adsorption tube 3. A base 27 is rotatably mounted on the bottom of the toothed disc 25. Multiple first gears 28 are rotatably mounted on the base 27 and mesh with the toothed disc 25. A second gear 29 is rotatably mounted on the bottom of the base 27 and is fixedly connected to the first gear 28. A third gear 31 is rotatably mounted on the bottom of the base 27 and meshes with the second gear 29. A connecting plate 30 is fixedly mounted on the bottom of the third gear 31. A stirring rod 23 is fixedly mounted on one end of the connecting plate 30, and multiple stirring blocks 24 are fixedly mounted on the stirring rod 23. When it is necessary to disperse the activated carbon on the inner wall, the base 27 is rotated. The base 27 drives the first gear 28 to rotate, the first gear 28 drives the second gear 29 to rotate, the second gear 29 drives the third gear 31 to rotate, and the third gear 31 drives the connecting plate 30 to rotate, which in turn drives the stirring rod 23 to rotate. The stirring rod 23 can rotate on its own axis and revolve around the first gear 28, so that the stirring block 24 can fully disperse the activated carbon inside, avoid the activated carbon from clumping and reducing the adsorption effect. At the same time, in the regeneration and reuse stage of activated carbon, dispersion helps hot gas to contact the activated carbon better, improves the oil and gas discharge efficiency, and improves the desorption effect.

[0030] A connecting shaft 26 is rotatably installed inside the activated carbon adsorption tube 3. One end of the connecting shaft 26 is fixedly connected to the base 27. A motor 34 is fixedly installed on the activated carbon adsorption tube 3. The output shaft of the motor 34 is fixedly connected to the connecting shaft 26. When the motor 34 is started, the output shaft of the motor 34 drives the connecting shaft 26 to rotate. A mounting hole 32 is opened on the gear plate 25. The connecting shaft 26 is located in the mounting hole 32. A fixing rod 22 is fixedly installed on the gear plate 25. One end of the fixing rod 22 is fixedly connected to the inner wall of the activated carbon adsorption tube 3.

[0031] Example 3 like Figure 1-2As shown, this invention provides a method for testing the amount of gasoline vapor emissions during the refueling process of a gasoline vehicle. It includes a gasoline vapor emission testing device as described in Examples 1 and 2. Two dedicated vapor collection hoods 5 are respectively placed over the outside of the test fuel nozzle's vapor collection hood, ensuring a tight fit. The mass of the activated carbon adsorption tube 3 in the vapor collection branch is weighed and recorded as m1, and the mass of the activated carbon adsorption tube 3 in the air comparison branch is recorded as mg1. A vacuum pump 1 is started to introduce nitrogen, generating a stable vacuum negative pressure. Two gas flow meters 2 are turned on, and the corresponding flow control valves 4 are adjusted to ensure that the gas flow rates in the vapor collection branch and the air comparison branch are consistent and precisely matched with the preset refueling flow rate of the fuel nozzle under test. The refueling operation is then initiated. During the entire refueling process, oil and gas enter the oil and gas collection branch through the dedicated oil and gas collection hood 5 and are adsorbed by the activated carbon adsorption tube 3 of the branch. At the same time, the air comparison branch collects ambient air. After refueling is completed, the device is turned off, and the mass of the activated carbon adsorption tube 3 in the oil and gas collection branch is weighed using an electronic balance and recorded as m2, and the mass of the activated carbon adsorption tube 3 in the air comparison branch is recorded as mk2. The mass change of the activated carbon adsorption tube 3 in the oil and gas collection branch is calculated according to the formula Δm=m2-m1, and the mass change of the activated carbon adsorption tube 3 in the air comparison branch is calculated according to the formula Δmk=mk2-mk1. Then, the actual oil and gas emission amount is calculated using the formula Δm-Δmk. After deducting the background interference of ambient air, the accurate oil and gas emission value is obtained.

[0032] The above specific embodiments are merely several optional embodiments of the present invention. Based on the technical solutions of the present invention and the relevant teachings of the above embodiments, those skilled in the art can make various alternative improvements and combinations to the above specific embodiments.

Claims

1. A device for testing the amount of gasoline vapor emitted during the refueling process of a gasoline vehicle, comprising a vacuum pump (1), characterized in that, It also includes a pair of activated carbon adsorption tubes (3), one end of which is fixedly installed with a first connector (33), one end of which is connected to a vacuum pump (1), and the other end of which is fixedly installed with a second connector (6), one end of which is fixedly installed with a flow control valve (4), one end of which is connected to a gas flow meter (2), one end of which is connected to a special oil and gas collection hood (5), and an auxiliary mechanism for regenerating and reusing the saturated adsorbent is provided inside the activated carbon adsorption tube (3), and a dispersing mechanism to prevent the adsorbent from clumping is provided inside the activated carbon adsorption tube (3).

2. The gasoline vehicle refueling process vapor emission testing device according to claim 1, characterized in that, The auxiliary mechanism includes a third connector (7) fixedly installed at one end of the activated carbon adsorption tube (3), a first connector (16) fixedly installed on the third connector (7), a heating block (15) fixedly installed on the first connector (16), an air pump (14) fixedly installed at one end of the heating block (15), an air storage tank (13) fixedly installed at one end of the air pump (14), a fourth connector (8) fixedly installed at the other end of the activated carbon adsorption tube (3), a second connector (17) fixedly installed at one end of the fourth connector (8), a cooling pipe (18) fixedly installed at one end of the second connector (17), a spiral tube (19) fixedly installed at one end of the cooling pipe (18), a collection trough (21) fixedly installed at one end of the spiral tube (19), and an air outlet (20) opened on the collection trough (21).

3. The gasoline vehicle refueling process vapor emission testing device according to claim 1, characterized in that, The dispersing mechanism includes a toothed disc (25) fixedly installed inside the activated carbon adsorption tube (3). A base (27) is rotatably installed on the bottom of the toothed disc (25). Multiple first gears (28) are rotatably installed on the base (27). The first gears (28) mesh with the toothed disc (25). A second gear (29) is rotatably installed on the bottom of the base (27). The second gear (29) is fixedly connected to the first gear (28). A third gear (31) is rotatably installed on the bottom of the base (27). The third gear (31) meshes with the second gear (29). A connecting plate (30) is fixedly installed on the bottom of the third gear (31). A stirring rod (23) is fixedly installed on one end of the connecting plate (30). Multiple stirring blocks (24) are fixedly installed on the stirring rod (23).

4. The gasoline vehicle refueling process vapor emission testing device according to claim 3, characterized in that, A connecting shaft (26) is rotatably installed inside the activated carbon adsorption tube (3), and one end of the connecting shaft (26) is fixedly connected to the base (27).

5. The gasoline vehicle refueling process vapor emission testing device according to claim 3, characterized in that, A motor (34) is fixedly installed on the activated carbon adsorption tube (3), and the output shaft of the motor (34) is fixedly connected to the connecting shaft (26).

6. The gasoline vehicle refueling process vapor emission testing device according to claim 4, characterized in that, The gear disc (25) has a mounting hole (32), and the connecting shaft (26) is located inside the mounting hole (32).

7. The gasoline vehicle refueling process vapor emission testing device according to claim 3, characterized in that, A fixing rod (22) is fixedly installed on the toothed disc (25), and one end of the fixing rod (22) is fixedly connected to the inner wall of the activated carbon adsorption tube (3).

8. The gasoline vehicle refueling process vapor emission testing device according to claim 2, characterized in that, A first electronic valve (9) is fixedly installed on the first connector (33), and a second electronic valve (10) is fixedly installed on the second connector (6).

9. A gasoline vehicle refueling process vapor emission testing device according to claim 2, characterized in that, A third electronic valve (11) is fixedly installed on the third connector (7), and a fourth electronic valve (12) is fixedly installed on the fourth connector (8).

10. A method for testing the amount of gasoline vapor emissions during the refueling process of a gasoline vehicle, characterized in that, A gasoline vehicle refueling process oil and gas emission testing device, including any one of claims 1-9, is used to cover the outside of the test fuel gun's gas collection cover with two dedicated oil and gas collection covers (5), ensuring that the covers fit tightly. The mass of the activated carbon adsorption tube (3) in the oil and gas collection branch is weighed and recorded as m1, and the mass of the activated carbon adsorption tube (3) in the air comparison branch is recorded as mg1. The vacuum pump (1) is started to introduce nitrogen to generate a stable vacuum negative pressure. The two gas flow meters (2) are turned on, and the gas flow rate in the oil and gas collection branch and the air comparison branch is kept consistent by adjusting the corresponding flow control valves (4), and is precisely matched with the preset refueling flow rate of the fuel gun to be tested. The refueling operation is started. During the entire refueling process, oil and gas are passed through the gas collection tube. The gas enters the oil and gas collection branch through the special oil and gas collection hood (5) and is adsorbed by the activated carbon adsorption tube (3) of the branch. At the same time, the air comparison branch collects ambient air synchronously. After the refueling is completed, the device is turned off. The mass of the activated carbon adsorption tube (3) in the oil and gas collection branch is weighed using an electronic balance and recorded as m2, and the mass of the activated carbon adsorption tube (3) in the air comparison branch is recorded as mk2. The mass change of the activated carbon adsorption tube (3) in the oil and gas collection branch is calculated according to the formula Δm=m2-m1. The mass change of the activated carbon adsorption tube (3) in the air comparison branch is calculated according to the formula Δmk=mk2-mk1. Then, the actual oil and gas emission amount = Δm-Δmk is obtained by deducting the background interference of ambient air.

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