Fuel evaporation control system applied to hybrid electric vehicle

Abstract

The fuel evaporation control system comprises a fuel tank isolation valve, a carbon canister assembly, an air filtering device and a leakage detection device, the fuel tank isolation valve is fixed to one side of the carbon canister assembly, and the interior of the fuel tank isolation valve communicates with the interior of the carbon canister assembly through a fuel tank connecting pipe; the leakage detection device is fixed at the end part of the carbon canister assembly, and the through hole leakage, communicated with the atmosphere, of the carbon canister assembly is connected with an air inlet joint of the leakage detection device through a rubber sleeve; the air filtering device is fixed to one side of the leakage detection device, and an inner inserting pipe of the air filtering device is connected with an air outlet connector of the leakage detection device. The fuel tank isolation valve, the leakage detection device and the air filtering device are directly integrated on the carbon tank assembly, so that the length of a pipeline is greatly shortened, the system layout is optimized, the overall size of the system is reduced, and the requirement of a narrow battery / electric control system coexistence space of the hybrid electric vehicle is met.

Description

Technical Field

[0001] The present invention belongs to the technical field of fuel evaporation control systems, and in particular relates to a fuel evaporation control system applied to a hybrid vehicle. Background Art

[0002] Hybrid vehicles not only have the fuel evaporation control system found in conventional fuel vehicles, but also require a battery pack and its electronic control system. This results in a smaller design space for the hybrid vehicle's fuel evaporation control module. Hybrid vehicles have more components than conventional fuel vehicles, making their layout difficult. To address this, designs typically place the fuel tank isolation valve on the fuel tank side. A vent line from the isolation valve is connected to the charcoal canister assembly, which is then connected to the leak detection device via a longer line. The leak detection device is then connected to the ash filter via a longer line. This results in a longer piping layout for the entire fuel evaporation control system, increasing the system's ventilation pressure drop and costs. Summary of the Invention

[0003] The purpose of the present invention is to address the deficiencies in the above-mentioned background technology and to provide a fuel evaporation control system for hybrid vehicles.

[0004] The technical solution adopted by the present invention is: a fuel evaporation control system applied to a hybrid vehicle, including a fuel tank isolation valve, a charcoal canister assembly, an air filter device and a leakage detection device, wherein the fuel tank isolation valve is fixed to one side of the charcoal canister assembly, and the interior of the fuel tank isolation valve is connected to the interior of the charcoal canister assembly through a fuel tank connecting pipe; the leakage detection device is fixed to the end of the charcoal canister assembly, and the leakage through the through hole of the charcoal canister assembly connecting to the atmosphere is connected to the air inlet joint of the leakage detection device through a rubber sleeve; the air filter device is fixed to one side of the leakage detection device, and the inner tube of the air filter device is connected to the air outlet joint of the leakage detection device.

[0005] Furthermore, a first mounting hole is provided on one side of the fuel tank isolation valve, and an inlay screw is provided on one side of the carbon canister shell of the carbon canister assembly. The fuel tank isolation valve is fixed to one side of the carbon canister assembly through the first mounting hole and the inlay screw.

[0006] Furthermore, the fuel tank connecting pipe includes a ventilation line, one end of the ventilation line is a female joint connected to the fuel tank isolation valve, and the other end is a flexible joint connected to the fuel vapor hole of the charcoal canister assembly, and both ends of the ventilation line are provided with clamps to prevent the line from detaching.

[0007] Furthermore, a clip is provided on the other side of the carbon canister assembly, and the clip is used to fix the wiring harness connecting the leakage detection device and the vehicle electronic control system.

[0008] Furthermore, the clamp includes a clamp and anti-collision plates arranged on both sides of the clamp, an Ω-shaped clamping groove is arranged in the middle of the clamp, the anti-collision plate is arranged perpendicular to the clamp, and the height of the anti-collision plate protruding from the surface of the carbon canister assembly is higher than the height of the clamp protruding from the surface of the carbon canister assembly.

[0009] Furthermore, the fuel tank isolation valve is provided with a first quick-insert male connector, a second quick-insert male connector and a first wiring harness plug interface, the first quick-insert male connector is used to connect the fuel tank, the second quick-insert male connector is connected to the female connector at one end of the fuel tank connecting pipe, and the first wiring harness plug interface is used to connect the vehicle's electronic control system.

[0010] Furthermore, a mounting plate is provided at the end of the carbon canister assembly, a second mounting hole is provided on the leakage detection device, and the leakage detection device is fixed to the end of the carbon canister assembly through the second mounting hole and the mounting plate.

[0011] Furthermore, the rubber sleeve includes a flange and a guide portion located on one side of the flange, the outer wall of the guide portion is provided with a sealing rib with a barb structure, the inner wall of the guide portion is provided with a groove step at one end away from the flange, and the inner wall at the junction of the flange and the guide portion is provided with a sealing strip.

[0012] Furthermore, an O-shaped sealing ring for sealing the inner hole of the air outlet connector and a buckle for clamping the air outlet connector are provided on the outer side of the inner tube.

[0013] Furthermore, a groove rib is provided on the edge of the contact surface between the air filter device and the leakage detection device, and the groove rib is clamped and connected to the flange boss of the leakage detection device.

[0014] The beneficial effects of the present invention are: By integrating the fuel tank isolation valve, leak detection device, and air filter device directly into the charcoal canister assembly instead of distributing them separately, the present invention significantly shortens the pipeline length, optimizes the system layout, reduces the overall system volume and cost, and adapts to the narrow battery / electronic control system coexistence space requirements of hybrid vehicles; and by reducing pipeline redundancy, the fuel vapor flow resistance is reduced, thereby improving the efficiency of the EVAP system.

[0015] The fuel tank isolation valve of the present invention is directly fixed to the carbon canister shell by embedded screws, which reduces the assembly process, reduces labor costs, and also reduces the lateral space occupied, avoiding interference with the battery pack / electronic control system; at the same time, the mechanical screw connection is more stable than the traditional clip, avoiding the loosening of components due to vehicle bumps or vibrations, thereby improving system reliability.

[0016] A standard female connector is provided at one end of the ventilation pipe of the present invention, which is convenient for connection with the fuel tank isolation valve; a soft connector is provided at the other end. The soft connector, such as a rubber material, can absorb pipe deformation and vibration, reduce stress concentration, and extend the life of the pipe; at the same time, the two ends of the ventilation pipe are fixed by clamps, which can prevent the ventilation pipe from loosening and detaching under high pressure or vibration, maintain airflow smoothness, and reduce the after-sales maintenance rate.

[0017] This invention employs a clip mounted on the canister assembly to directly secure the wiring harness. This prevents the harness from dangling and occupying additional space. It also prevents friction with sharp components, which could cause short circuits or disconnections, improving electrical safety. Centralized wiring harness positioning facilitates quick location during maintenance, reducing troubleshooting time. Furthermore, the Ω-shaped slot provides elastic clamping force, and the bumper plate, positioned higher than the clamping plate, forms a physical barrier to prevent damage to the wiring harness from external impact. The vertical placement of the bumper plate saves lateral space, accommodating the high-density layout requirements of hybrid vehicles.

[0018] The fuel tank isolation valve of the present invention is integrated with a quick-insert male connector, which is directly connected to the fuel tank and the carbon canister. The quick-insert male connector simplifies the pipe connection and can be installed without tools, thereby improving the efficiency of the production line.

[0019] The leakage detection device of the present invention is directly fixed to the end of the carbon canister through a mounting plate, shortening the gas path distance between the detection device and the carbon canister and reducing pressure drop loss; and the short gas path can reduce response delay, and the leakage detection device can sense the system sealing status more quickly.

[0020] The barbed sealing ribs of the rubber sleeve of the present invention form a double lock with the groove step, and the rubber sleeve automatically enhances the seal when it is under pressure to prevent the escape of fuel vapor. The guide part guides the installation direction to avoid sealing failure caused by assembly deviation.

[0021] The air filter and leak detection device of this invention utilize an O-ring and buckle combination to achieve a dual dynamic and static seal, adapting to material deformation caused by temperature changes and preventing air leakage. The buckle structure allows for manual disassembly, facilitating replacement or maintenance of the detection device. Furthermore, the slotted ribs on the air filter engage with the flange boss of the leak detection device, preventing displacement of the air filter due to vehicle vibration and ensuring air path stability. The rib structure maintains strength while reducing material usage, meeting the weight reduction requirements of hybrid vehicles. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a schematic diagram of the overall connection of the structure of the present invention.

[0023] Figure 2 It is a schematic diagram of the structural explosion of the present invention.

[0024] Figure 3 Schematic diagram of the fuel tank isolation valve of the present invention.

[0025] Figure 4This is a schematic diagram of the carbon canister assembly from a first perspective of the present invention.

[0026] Figure 5 This is a schematic diagram of the carbon canister assembly from a second perspective of the present invention.

[0027] Figure 6 This is a schematic diagram of the carbon canister assembly from a third perspective of the present invention.

[0028] Figure 7 This is a schematic diagram of the carbon canister assembly from a fourth perspective of the present invention.

[0029] Figure 8 This is a schematic diagram of the carbon canister assembly from a fifth perspective of the present invention.

[0030] Figure 9 This is a partial schematic diagram of the carbon canister assembly of the present invention from a sixth perspective.

[0031] Figure 10 for Figure 9 Middle AA cross-section.

[0032] Figure 11 It is a cross-sectional view of the rubber sleeve of the present invention.

[0033] Figure 12 Schematic diagram of an air filter device of the present invention.

[0034] Figure 13 for Figure 12 A partial enlarged schematic diagram of point B in the middle.

[0035] Figure 14 Schematic diagram of the leakage detection device of the present invention.

[0036] Figure 15 Schematic diagram of the fuel tank connecting pipe of the present invention.

[0037] In the figure, 10-flange nut; 20-fuel tank isolation valve; 21-first mounting hole; 22-first quick-insert male connector; 23-first wiring harness plug interface; 24-second quick-insert male connector; 30-carbon canister assembly; 31-inlaid screw; 31a-stud; 31b-boss; 32-mounting bracket; 32a-pre-hanging hole; 32b-upper bracket; 32c-lower bracket; 33-clip; 33a-clamping plate; 33b-anti-collision plate; 33c-clip groove; 34-leakage through hole; 35-mounting plate; 35a-step hole; 35b-rubber shock absorber pad; 35c-metal bushing; 3 6-Fuel vapor hole; 40-Rubber sleeve; 41-Sealing rib; 42-Flange; 43-Sealing strip; 44-Groove step; 45-Guide; 50-Air filter; 51-Inner tube; 52-Sealing ring; 53-Snap buckle; 54-Groove rib plate; 55-Atmosphere connecting pipe; 60-Leak detection device; 61-Inlet connector; 62-Outlet connector; 63-Flange boss; 64-Second wiring harness plug interface; 65-Second mounting hole; 70-Self-tapping screw; 80-Fuel tank connecting pipe; 81-Female connector; 82-Clamp; 83-Ventilation pipe; 84-Flexible connector. DETAILED DESCRIPTION

[0038] The following is a further description of specific embodiments of the present invention in conjunction with the accompanying drawings. It should be noted that the description of these embodiments is intended to facilitate understanding of the present invention and does not constitute a limitation of the present invention. In addition, the technical features involved in the various embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.

[0039] like Figure 1-2 As shown, the present invention provides a fuel evaporation control system for a hybrid vehicle, comprising a fuel tank isolation valve 20, a charcoal canister assembly 30, an air filter device 50, and a leakage detection device 60. The fuel tank isolation valve 20 is fixed to one side of the charcoal canister assembly 30, and the interior of the fuel tank isolation valve 20 is connected to the interior of the charcoal canister assembly 30 via a fuel tank connecting pipe 80. The leakage detection device 60 is fixed to the end of the charcoal canister assembly 30, and the leakage through the through hole of the charcoal canister assembly 30 connecting to the atmosphere is connected to the air inlet connector of the leakage detection device 60 via a rubber sleeve 40. The air filter device 50 is fixed to one side of the leakage detection device 60, and the inner tube of the air filter device 50 is connected to the air outlet connector of the leakage detection device 60.

[0040] By integrating the fuel tank isolation valve 20, the leakage detection device 60, and the air filter device 50 directly into the charcoal canister assembly 30 rather than distributing them separately, the present invention shortens the piping layout of the entire fuel evaporation control system, optimizes the system layout, reduces the overall system volume and cost, and adapts to the narrow battery / electronic control system coexistence space requirements of hybrid vehicles; and by reducing piping redundancy, it can avoid an increase in the system ventilation pressure drop.

[0041] In some embodiments, as Figure 3 As shown, the fuel tank isolation valve 20 is provided with two first mounting holes 21 that cooperate with the embedded screws 31 of the carbon canister assembly, a first quick-insert male connector 22 and a second quick-insert male connector 24 that are connected to the fuel tank 22 and the carbon canister assembly 24 respectively, and a first wiring harness plug interface 23 that is connected to the vehicle electronic control system.

[0042] In some embodiments, as Figure 4-10 As shown, the carbon canister assembly is provided with two embedded screws 31 for fixing the fuel tank isolation valve 20, a mounting plate 35 for fixing the leakage detection device 60, a leakage through-hole 34 that is interference-fitted with the rubber sleeve 40 and communicates with the leakage detection device 60, a clamp 33 for fixing the wiring harness connecting the leakage detection device to the vehicle electronic control system, a mounting bracket 32 ​​for connecting to the vehicle, and a fuel vapor hole 36 for communicating with the fuel tank connecting pipe. The specific structures of each connecting component are as follows: The embedded screw 31 is pre-buried in the carbon canister housing and is integrally injection molded therewith. The protruding height of the threaded stud 31a on the embedded screw 31 is greater than the height of the mounting bracket of the fuel tank isolation valve (20). A boss 31b supporting the mounting bracket of the fuel tank isolation valve (20) is provided at the pre-buried position of the stud, and the heights of the two bosses 31b are located on the same plane.

[0043] The mounting bracket 32 ​​is provided with at least three mounting points, namely a pre-hanging hole 32a for pre-hanging to the hook plate of the whole vehicle, an upper bracket 32b and a lower bracket 32c for fixing to the whole vehicle. The upper bracket 32b and the lower bracket 32c can determine whether to add a metal bushing according to the weight of the carbon canister assembly. It is recommended to install a metal bushing at the mounting hole to ensure its installation reliability.

[0044] The clamp 33 includes a clamping plate 33a and anti-collision plates 33b arranged on both sides of the clamping plate. An Ω-shaped slot 33c is set in the middle of the clamping plate 33a, and the diameter of the slot is smaller than the diameter of the wiring harness it clamps; the anti-collision plate 33b is arranged perpendicular to the clamping plate, and the height of the anti-collision plate 33b protruding from the surface of the carbon canister assembly is higher than the height of the clamping plate 33a protruding from the surface of the carbon canister assembly, and the width between the two anti-collision plates 33b is greater than the width of the clamping plate 33a, which can avoid damage to the clamping plate 33a due to external force.

[0045] If the center line of the pre-hanging hole 32a on the mounting bracket 32 ​​and the mounting bracket are both parallel to the ground, the leakage through hole 34 is inclined at a certain angle such as 10° toward the ground, which can facilitate the discharge of water droplets in the leakage detection device and prevent moisture from affecting the detection accuracy.

[0046] The mounting plate 35 includes three stepped holes 35a, three rubber shock-absorbing pads 35b and three metal bushings 35c. The large hole diameter of the stepped hole 35a is larger than the outer edge diameter of the nut of the self-tapping screw 70. The small hole diameter of the stepped hole 35a is interference fit or clearance fit with the rubber shock-absorbing pad 35b. The outer ring diameter of the metal bushing 35c is interference fit with the inner ring of the rubber shock-absorbing pad 35b. The inner ring diameter of the metal bushing 35c is larger than the outer diameter of the thread of the self-tapping screw 70.

[0047] In some embodiments, as Figure 11 As shown, the rubber sleeve 40 includes a flange platform 42 and a guide portion 45 located on one side of the flange platform 42. The outer wall of the guide portion 45 is provided with a sealing rib 41 for sealing the leakage through hole 34 of the carbon canister assembly. The sealing rib 41 is designed as a barb structure, which can be easily inserted into the leakage through hole 34 of the carbon canister assembly and can make the sealing rib have a certain elasticity, so as to avoid the occurrence of poor sealing problems caused by external vibration; after the rubber sleeve is assembled, the flange platform 42 fits with the end face of the leakage through hole 34 of the carbon canister assembly; the inner wall of the flange platform 42 and the guide portion 45 is provided with a sealing strip 43, which can avoid airflow leakage from the inner wall side; the inner wall of the guide portion 45 is provided with a groove step 44 at the end away from the flange platform, and the groove step 44 can accommodate the pipe joint flange of the leakage detection device.

[0048] In some embodiments, as Figure 12 、 Figure 13 As shown, the air filter device 50 is provided with an inner tube 51 connected to the leakage detection device and an atmospheric connecting pipe 55 connected to the atmosphere. The outer side of the inner tube 51 is provided with an O-ring 52 for sealing the inner hole of the air outlet joint and a buckle 53 for clamping the air outlet joint. The edge of the contact surface where the air filter device 50 and the leakage detection device 60 are connected is provided with a groove rib plate 54. The groove rib plate 54 is clamped and connected to the flange boss 63 of the leakage detection device 60 to prevent the air filter device from rotating.

[0049] In some embodiments, as Figure 14 As shown, the leakage detection device 60 is provided with an air inlet connector 61 nested with the rubber sleeve 40, an air outlet connector 62 connected to the air filter device 50, a second wiring harness plug interface 64 connected to the vehicle electronic control system, and a second mounting hole 65 connected to the carbon canister assembly.

[0050] In some embodiments, as Figure 15As shown, the fuel tank connecting pipe 80 includes a ventilation line 83, one end of the ventilation line 83 is a female connector 81 that matches the second quick-insert male connector 24 of the fuel tank isolation valve 20, and the other end is a flexible connector 84 connected to the fuel vapor hole 36 of the charcoal canister assembly 30. The ventilation line 83 has clamps 82 at both ends at the positions of the female connector and the flexible connector to prevent the line from detaching. The shape of the ventilation line is determined by the assembly position.

[0051] After the fuel tank isolation valve 20 is assembled to the charcoal canister assembly 30, it is fixed by the flange nut 10. After the fuel tank connecting pipe 80 is assembled, the fuel tank isolation valve 20 and the charcoal canister assembly 30 can be connected to each other. After the leakage detection device 60 is assembled to the charcoal canister assembly 30, the leakage detection device 60 and the charcoal canister assembly 30 can be connected to each other and fixed by the self-tapping screw 70. After the air filter device 50 is assembled to the leakage detection device 60, the leakage detection device 60 and the air filter device 50 can be connected to each other. After the present invention is assembled into the fuel system, because the fuel tank isolation valve 20 is in a normally closed state, the fuel vapor in the high-pressure fuel tank can only enter the charcoal canister assembly 30 when the pressure in the high-pressure fuel tank exceeds a certain threshold, thereby reducing fuel evaporative emissions. When the system needs to perform a leak detection, the electronic control system supplies current to the leak detection device 60 to start it working. The ECU determines whether there is a leak in the entire fuel system based on the current change trend feedback from the leak detection device 60.

[0052] The present invention systematically solves the problems of space conflicts, pressure drop losses and excessive costs in the hybrid vehicle fuel evaporation control system through modular integrated design of the fuel tank isolation valve + carbon canister + detection device + filter, quick connection quick plug / snap, redundant sealing O-rings / barbed ribs and other technologies, significantly improving the sealing, reliability and maintenance convenience of the hybrid vehicle fuel evaporation control system, while meeting strict emission regulations and compact space requirements, and has significant technical advantages and high engineering practical value.

[0053] The above are only specific embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be covered by the scope of protection of the present invention. Matters not described in detail in this specification belong to the prior art known to those skilled in the art.

Claims

1. A fuel evaporation control system for a hybrid vehicle, characterized by: It includes a fuel tank isolation valve (20), a carbon canister assembly (30), an air filter device (50) and a leakage detection device (60), The fuel tank isolation valve (20) is fixed to one side of the carbon canister assembly (30), and the interior of the fuel tank isolation valve (20) is connected to the interior of the carbon canister assembly (30) through the fuel tank connecting pipe (80); The leakage detection device (60) is fixed to the end of the carbon canister assembly (30), and the through hole of the carbon canister assembly (30) connected to the atmosphere is connected to the air inlet joint of the leakage detection device (60) through the rubber sleeve (40); The air filter device (50) is fixed to one side of the leakage detection device (60), and the inner tube of the air filter device (50) is connected to the air outlet connector of the leakage detection device (60).

2. The fuel evaporation control system for hybrid vehicles according to claim 1, characterized in that: A first mounting hole (21) is provided on one side of the fuel tank isolation valve (20), and an inlay screw (31) is provided on one side of the carbon canister housing of the carbon canister assembly (30). The fuel tank isolation valve (20) is fixed to one side of the carbon canister assembly (30) through the first mounting hole (21) and the inlay screw (31).

3. The fuel evaporation control system for hybrid vehicles according to claim 1, characterized in that: The fuel tank connecting pipe (80) includes a vent pipe (83), one end of the vent pipe (83) is a female connector (81) connected to the fuel tank isolation valve, and the other end is a flexible connector (84) connected to the fuel vapor hole of the carbon canister assembly. Both ends of the vent pipe are respectively provided with clamps (82) to prevent the pipe from being separated.

4. The fuel evaporation control system for hybrid vehicles according to claim 1, characterized in that: A clamp (33) is provided on the other side of the carbon canister assembly (30), and the clamp (33) is used to fix the wiring harness connecting the leakage detection device (60) and the entire vehicle electronic control system.

5. The fuel evaporation control system for hybrid vehicles according to claim 4, characterized in that: The clamp (33) includes a clamp (33a) and anti-collision plates (33b) arranged on both sides of the clamp, an Ω-shaped clamping groove (33c) is arranged in the middle of the clamp (33a), the anti-collision plate (33b) is arranged perpendicular to the clamp (33), and the height of the anti-collision plate (33b) protruding from the surface of the carbon canister assembly is higher than the height of the clamp (33a) protruding from the surface of the carbon canister assembly.

6. The fuel evaporation control system for hybrid vehicles according to claim 1, characterized in that: The fuel tank isolation valve (20) is provided with a first quick-insert male connector (22), a second quick-insert male connector (24), and a first wiring harness connector (23); the first quick-insert male connector (22) is used for connecting to the fuel tank; the second quick-insert male connector (24) is connected to the female connector at one end of the fuel tank connecting pipe (80); and the first wiring harness connector (23) is used for connecting to the vehicle's electronic control system.

7. The fuel evaporation control system for hybrid vehicles according to claim 1, characterized in that: The end of the carbon canister assembly (30) is provided with a mounting plate (35), the leakage detection device (60) is provided with a second mounting hole (65), and the leakage detection device (60) is fixed to the end of the carbon canister assembly (30) by cooperating with the mounting plate (35) through the second mounting hole (65).

8. The fuel evaporation control system for hybrid vehicles according to claim 1, characterized in that: The rubber sleeve (40) comprises a flange (42) and a guide portion (45) located on one side of the flange. The outer wall of the guide portion (45) is provided with a sealing rib (41) with a barb structure. The inner wall of the guide portion (45) is provided with a groove step (44) at one end away from the flange. The inner wall of the flange (42) and the guide portion (45) is provided with a sealing strip (43) at the junction of the flange (42) and the guide portion (45).

9. The fuel evaporation control system for hybrid vehicles according to claim 1, characterized in that: An O-shaped sealing ring (52) for sealing the inner hole of the air outlet connector and a buckle (53) for clamping the air outlet connector are provided on the outer side of the inner insert tube (51).

10. The fuel evaporation control system for hybrid vehicles according to claim 1, characterized in that: A clamping groove rib plate (54) is provided at the edge of the contact surface where the air filter device (50) and the leakage detection device (60) meet, and the clamping groove rib plate (54) is clamped and connected to the flange boss (63) of the leakage detection device (60).

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