Design structure for controlling carbon canister to escape and discharge

Abstract

The invention discloses a design structure for controlling escape emission of a carbon canister, and relates to the technical field of carbon canisters. Comprising a carbon canister body and a hydrocarbon buffer cavity arranged at an atmosphere opening of the carbon canister body, the hydrocarbon buffer cavity is communicated with the atmosphere opening of the carbon canister body and used for delaying escape of hydrocarbon from the carbon canister to the atmosphere, the total inner volume of the hydrocarbon buffer cavity is larger than 40 ml, the length of the center line of a core path is larger than 200 mm, and the sectional area of the path is not smaller than 150 mm. And the hydrocarbon buffer cavity at least comprises a corner or a variable-diameter section which is greater than or equal to 90 degrees. By means of the special structural design of the hydrocarbon buffer cavity, the higher hydrocarbon emission reduction rate is achieved within the day and night temperature change range, the emission reduction effect exceeds that of a traditional carbon rod design, the higher emission reduction effect is achieved in cooperation with the traditional carbon rod design, and the strict requirements of environmental protection laws and regulations are met.

Description

Technical Field

[0001] This invention relates to the field of charcoal canister technology, specifically a design structure for controlling the emission of charcoal from the canister. Background Technology

[0002] During use, the fuel tanks of light-duty fuel vehicles generate a large amount of gasoline vapor due to factors such as temperature changes and vehicle vibration. If the hydrocarbons contained in the vapor are directly emitted into the atmosphere, they will cause serious environmental problems such as photochemical smog and ozone pollution. Therefore, existing vehicles are equipped with charcoal canisters as a gasoline vapor emission control system. The carbon powder in the charcoal canister is used to adsorb hydrocarbons and reduce pollutant emissions.

[0003] Trace amounts of hydrocarbons escaping from the charcoal canister during vehicle idling are subject to strict control. Currently, existing methods for controlling hydrocarbon escape from the charcoal canister mainly focus on adding carbon rods for recapture. However, this design has significant drawbacks: first, adding carbon rods increases the production cost of the charcoal canister; second, the carbon rods occupy extra space, increasing the size of the charcoal canister and making it difficult to adapt to the compact chassis layout of hybrid and range-extended electric vehicles; and third, the carbon rods need to be replaced periodically after adsorption saturation, increasing user costs and maintenance frequency. Therefore, there is an urgent need for a lower-cost, more compact, and more effective charcoal canister emission control structure. Summary of the Invention

[0004] The purpose of this invention is to provide a design structure for controlling the emission of charcoal from the canister, so as to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a design structure for controlling the emission of charcoal from a canister, comprising:

[0006] The charcoal canister body and the hydrocarbon buffer chamber located at the vent to the atmosphere of the charcoal canister body;

[0007] The hydrocarbon buffer chamber is connected to the vent of the carbon canister body to slow down the escape of hydrocarbons from the carbon canister into the atmosphere.

[0008] The total internal volume of the hydrocarbon buffer chamber is greater than 40 ml, the centerline length of the core path is greater than 200 mm, the cross-sectional area of ​​the passage is not less than 150 mm², and the hydrocarbon buffer chamber contains at least one bend or diameter change section of greater than or equal to 90°.

[0009] Furthermore, the carbon canister body includes a carbon canister shell, carbon powder disposed inside the carbon canister shell, and non-woven fabric for dust prevention. The carbon canister shell is provided with a single cavity, a double cavity, or multiple chambers, with adsorption ports and desorption ports on the chambers. An air vent is provided at the end of the carbon canister shell, and the non-woven fabric is located between the air vent and the chamber.

[0010] Furthermore, the hydrocarbon buffer chamber is adapted to the structure of the carbon canister body without increasing the overall space occupied by the carbon canister, and the hydrocarbon buffer chamber and the carbon canister body are integrally formed or detachably sealed through sealing connectors.

[0011] Furthermore, the design structure is suitable for hydrocarbon escape control under diurnal temperature variations of 10-45℃ and is applicable to hybrid vehicles, range-extended vehicles, and gasoline-powered vehicles.

[0012] Furthermore, the hydrocarbon buffer chamber has 1-3 turns, and the path length between adjacent turns is not less than 50mm.

[0013] Furthermore, the variable diameter section of the hydrocarbon buffer chamber is designed as a gradually expanding variable diameter, a gradually contracting variable diameter, or an alternating variable diameter, and the length of the variable diameter section is 1 / 5 to 1 / 3 of the total length of the core path.

[0014] Furthermore, a dust filter is provided at the outlet of the hydrocarbon buffer chamber. The dust filter has a pore size of 5-20μm and is detachably connected to the outlet of the hydrocarbon buffer chamber by a snap-fit ​​mechanism.

[0015] Compared with the prior art, the beneficial effects of the present invention are:

[0016] The design structure for controlling the emission of carbon canisters achieves a higher hydrocarbon emission reduction rate within a day-night temperature range through the special structural design of the hydrocarbon buffer chamber. The emission reduction effect exceeds that of traditional carbon rod designs. When combined with traditional carbon rod designs, it achieves even higher emission reduction effects and meets stringent environmental regulations.

[0017] At the same time, without adding extra carbon rods, production costs can still be reduced and the same or even better emission reduction effect can be achieved as with the use of carbon rods. Furthermore, there is no need to replace carbon rods later, reducing user maintenance costs.

[0018] Without increasing the volume of the charcoal canister itself, it is suitable for scenarios with high space requirements, such as hybrid and range-extended electric vehicles, while also being compatible with traditional fuel vehicles, making it widely applicable. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the overall structure of the present invention;

[0020] Figure 2 This is a schematic diagram of the structure of Embodiment 2 of the present invention;

[0021] Figure 3 This is a schematic diagram of the structure of Embodiment 3 of the present invention;

[0022] Figure 4 This is a schematic diagram of the structure of Embodiment 4 of the present invention;

[0023] Figure 5 This is a schematic diagram of the structure of Embodiment 5 of the present invention.

[0024] In the diagram: 1. Carbon canister shell; 2. Carbon powder; 3. Adsorption port; 4. Desorption port; 5. Vent to the atmosphere; 6. Non-woven fabric; 7. Hydrocarbon buffer chamber; 8. Corner; 9. Variable diameter section; 10. Anti-adsorption coating; 11. Dust filter. Detailed Implementation

[0025] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0026] like Figure 1 As shown, the present invention provides a technical solution: a design structure for controlling the emission of charcoal from a charcoal canister, comprising a charcoal canister body and a hydrocarbon buffer chamber 7;

[0027] The charcoal canister body includes a charcoal canister shell 1, carbon powder 2, non-woven fabric 6, adsorption port 3, desorption port 4, and vent 5. The charcoal canister shell 1 has a single cavity, double cavity, or multiple cavities. The carbon powder 2 is filled in the cavities to adsorb hydrocarbons in gasoline vapor. The non-woven fabric 6 is placed between the vent 5 and the cavities to prevent dust from entering the cavities and affecting the adsorption effect of the carbon powder 2. The adsorption port 3 is used to connect to the fuel tank to receive gasoline vapor. The desorption port 4 is used to connect to the engine intake system to desorb and reuse the hydrocarbons adsorbed by the carbon powder 2.

[0028] The hydrocarbon buffer chamber 7 is located at the vent 5 of the carbon canister body and is sealed and connected to the vent 5. Its design is based on the characteristic that hydrocarbons are heavier than air and the laws of air flow, and it delays the escape of hydrocarbons through specific structural parameters:

[0029] The total volume of the hydrocarbon buffer chamber 7 is greater than 40ml to ensure sufficient buffer space to accommodate any hydrocarbons that may escape, preventing rapid overflow of hydrocarbons due to insufficient space. The centerline length of its path is greater than 200mm to extend the escape path of hydrocarbons and increase their residence time in the hydrocarbon buffer chamber 7. Gravity is used to cause some hydrocarbons to settle. The cross-sectional area of ​​the passage is not less than 150mm² to ensure normal pressure balance inside and outside the carbon canister and to prevent the adsorption and desorption functions of the carbon canister from being affected by the passage being too narrow.

[0030] The hydrocarbon buffer chamber 7 includes at least one turning angle 8 of 90° or greater, or a variable diameter section 9 is added to the chamber of the hydrocarbon buffer chamber 7 to change the flow direction and speed of hydrocarbons using fluid dynamics principles, thereby creating a turbulent effect and further hindering their escape.

[0031] The fluid shape, size, and volume of the hydrocarbon buffer chamber 7 have been optimized to fit the existing structure of the carbon canister body without increasing the overall volume of the carbon canister. The hydrocarbon buffer chamber 7 can be integrally molded with the carbon canister body, or connected to the carbon canister shell 1 by means of detachable sealing such as threaded connection or snap-fit ​​connection, which facilitates later maintenance and replacement. A dust filter 11 is added at the outlet of the hydrocarbon buffer chamber 7 to further improve the dust prevention effect and prevent dust from entering the hydrocarbon buffer chamber 7 and affecting the smoothness of the passage.

[0032] The technical solution of the present invention will be described below with reference to specific embodiments:

[0033] Example 1:

[0034] like Figure 1 As shown, the total internal volume of the hydrocarbon buffer chamber 7 is 45ml, the path centerline length is 210mm, and it has a 90° turn 8. The hydrocarbon buffer chamber 7 is integrally injection molded or threadedly connected to the carbon canister body. The dust filter 11 is made of polyester fiber with a pore size of 10μm.

[0035] Example 2:

[0036] like Figure 2 As shown, the hydrocarbon buffer chamber 7 has a total internal volume of 50ml, a core path centerline length of 250mm, and two 90° corners 8 with an 80mm spacing between adjacent corners 8. The hydrocarbon buffer chamber 7 is integrally injection molded or threadedly connected to the carbon canister body. The dust filter 11 has a pore size of 10μm and is made of polyester fiber.

[0037] Example 3:

[0038] like Figure 3 As shown, the total internal volume of the hydrocarbon buffer chamber 7 is 42ml, the length of the core path centerline is 210mm, and it is equipped with a gradually expanding variable diameter section 9 with a length of 50mm. The hydrocarbon buffer chamber 7 is integrally injection molded or threadedly connected to the carbon canister body. The dust filter 11 has a pore size of 10μm and is made of polyester fiber.

[0039] Example 4:

[0040] like Figure 4 As shown, the total internal volume of the hydrocarbon buffer chamber 7 is 42ml, the length of the core path centerline is 210mm, and it is equipped with a gradually expanding variable diameter section 9 with a length of 50mm. The hydrocarbon buffer chamber 7 is integrally injection molded or threadedly connected to the carbon canister body. The dust filter 11 has a pore size of 10μm and is made of polyester fiber.

[0041] Example 5:

[0042] like Figure 5 As shown, the hydrocarbon buffer chamber 7 has a total internal volume of 55ml, a core path centerline length of 210mm, and is equipped with a 90° turn 8 and an alternating variable diameter section 9 with a length of 60mm. The hydrocarbon buffer chamber 7 is integrally injection molded or threadedly connected to the carbon canister body. The dust filter 11 has a pore size of 10μm and is made of polyester fiber.

[0043] Experimental data and effect verification

[0044] To verify the hydrocarbon escape control effect of the structure designed in this invention, samples from the above four embodiments were selected for comparative experiments with traditional carbon canisters and traditional carbon-adding rod carbon canisters. The experimental conditions and results are as follows:

[0045] Experimental conditions:

[0046] Ambient temperature: 20-35℃ day and night cycle, 35℃ during the day and 20℃ at night, with heating and cooling rates meeting the requirements of the regulatory test curve;

[0047] Experimental subject: Carbon canister of the same model of hybrid vehicle, with a carbon canister shell volume of 1.2L and carbon powder filling amount of 800g;

[0048] Test method: Refer to the static emission test method in GB18352.6-2016 "Limits and Measurement Methods for Pollutant Emissions from Light-Duty Vehicles (China VI)";

[0049] Detection instrument: Gas chromatograph (detection accuracy 0.01 mg / m³)

[0050] Test sample hydrocarbon emissions (mg / 24h) Emission reduction rate compared to traditional charcoal canisters Production cost (RMB / unit) Relative cost percentage of carbon enrichment rod design Changes in the volume of the charcoal canister body Traditional charcoal canisters (control group 1) 102.8 185 Reference volume V Traditional carbon-raising rod charcoal canister (control group 2) 14.2 86.19% 85 100% 1.22V Example 1 14.5 85.89% 5 6% V Example 2 12.3 88.04% 10 12% V Example 3 14.0 86.38% 8 9% V Example 4 12.3 88.04% 10 12% V Example 5 12.5 87.84% 12 14% V

[0051] The hydrocarbon emissions of the samples in each embodiment of the present invention are significantly lower than those of traditional carbon canisters, with emission reduction rates reaching 85.89%-88.04%. Among them, the emission reduction effects of Embodiments 2 and 5 are significantly better than those of traditional carbon-enhancing rod carbon canisters. The production cost of each embodiment of the present invention is only 6%-14% of that of traditional carbon-enhancing rod designs, showing a significant cost advantage. Furthermore, none of the embodiments increase the carbon canister volume, making them more adaptable. After 1000 hours of continuous cycle testing, the hydrocarbon emissions of the samples in each embodiment did not increase significantly, the dust filter 11 did not become clogged, and the structure exhibited good stability and reliability.

[0052] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended embodiments and their equivalents.

Claims

1. A design structure for controlling the emission of charcoal from a charcoal canister, characterized in that, include: The carbon canister body and the hydrocarbon buffer chamber (7) located at the vent (5) of the carbon canister body; The hydrocarbon buffer chamber (7) is connected to the vent (5) of the carbon canister body to delay the escape of hydrocarbons from the carbon canister into the atmosphere. The total internal volume of the hydrocarbon buffer chamber (7) is greater than 40 ml, the centerline length of the core path is greater than 200 mm, and the hydrocarbon buffer chamber (7) contains at least one turning angle (8) or variable diameter section (9) greater than or equal to 90°.

2. The design structure for controlling the emission of charcoal from the canister according to claim 1, characterized in that, The carbon canister body includes a carbon canister shell (1), carbon powder (2) disposed inside the carbon canister shell (1), and a non-woven fabric (6) for dust prevention. The carbon canister shell (1) is provided with a single cavity, a double cavity, or multiple chambers. The chambers are provided with an adsorption port (3) and a desorption port (4). The end of the carbon canister shell (1) is provided with a vent (5), and the non-woven fabric (6) is located between the vent (5) and the chamber.

3. The design structure for controlling the emission of charcoal from the canister according to claim 1, characterized in that, The hydrocarbon buffer chamber (7) is adapted to the structure of the carbon canister body and does not increase the overall space occupied by the carbon canister.

4. The design structure for controlling the emission of charcoal from the canister according to claim 1, characterized in that, The design structure is suitable for hydrocarbon escape control under diurnal temperature variations of 10-45℃ and is applicable to hybrid vehicles, range-extended vehicles, and gasoline-powered vehicles.

5. The design structure for controlling the emission of charcoal from the canister according to claim 1, characterized in that, The hydrocarbon buffer chamber (7) has 1-3 turns (8), and the path length between adjacent turns (8) is not less than 50mm.

6. The design structure for controlling the emission of charcoal from the canister according to claim 1, characterized in that, The variable diameter section (9) of the hydrocarbon buffer chamber (7) is designed as a gradually expanding variable diameter, a gradually shrinking variable diameter, or an alternating variable diameter, and the length of the variable diameter section (9) is 1 / 5 to 1 / 3 of the total length of the core path.

7. The design structure for controlling the emission of charcoal from the canister according to claim 1, characterized in that, The outlet of the hydrocarbon buffer chamber (7) is provided with a dust filter (11), the pore size of the dust filter (11) is 5-20μm, and the dust filter (11) and the outlet of the hydrocarbon buffer chamber (7) are connected by a snap-fit ​​detachable connection.

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