A double-wall high-performance refueling limit valve and its working method

Abstract

A double-wall high-performance refueling limit valve and its working method, including a shell, a float assembly, and a bottom cover, wherein the shell is sleeved on the outside of the float assembly, and the bottom cover is installed at the bottom of the shell and contacts the bottom of the float assembly through a spring; the float assembly includes a float shell, a sealing door, and a float, wherein the sealing door is assembled on the upper part of the float and is placed inside the float shell together with the float, and the spring is installed between the bottom of the float and the bottom cover, and the float can move up and down in the float shell; a secondary opening vent is provided at the center of the upper end surface of the float shell. The double-wall high-performance refueling limit valve and its working method of the present invention realize rapid opening and pressure reduction under high pressure conditions through a two-stage opening mode of the valve, thereby improving the safety of the fuel tank and vehicle system; a double-wall structure is adopted to realize zero dynamic leakage of liquid under dynamic conditions; modular design realizes different closing heights to meet diverse needs.

Description

Technical Field

[0001] The invention relates to the technical field of automobile fuel management systems, and in particular to a double-wall high-performance refueling limiting valve and a working method thereof. Background Art

[0002] The refueling limit valve is an important component of the automobile fuel management system. The refueling limit valve directly determines the total volume of refueling during refueling. At the same time, as the fuel consumption gradually decreases, the valve is required to be opened in time to increase exhaust. As we all know, the more liquid there is in a limited container, the less the liquid shakes during the movement of the container, and the less liquid, the greater the shake. For automobile fuel tanks, the greater the fuel shake, the more oil vapor is generated and needs to be discharged to avoid causing the tank to expand and deform, which will also bring great safety hazards.

[0003] As the use of fuel in the fuel tank gradually decreases, the more oil vapor is generated, the greater the pressure in the fuel tank, which inevitably requires the refueling limit valve to be opened in time to exhaust, eliminate the pressure in the fuel tank, and reduce safety hazards. The main factors that affect whether the refueling limit valve can be opened in time are: (1) the balance value of the gravity, buoyancy, and float spring force of the valve core float; (2) the internal pressure of the fuel tank; (3) the size of the vent hole.

[0004] The pressure calculation formula F (pressure) = P (pressure) * S (area) is used for analysis: (1) F (pressure): the balance value of the valve core float's gravity, buoyancy, and float spring force, which is usually set as a constant; (2) P (pressure): the fuel evaporates and produces steam, the tank volume is a constant, and the pressure rises; (3) S (area): the size of the vent hole. As can be seen from the above, when the pressure at which the valve opens is constant, the larger the vent hole S, the smaller the pressure P inside the tank; and the smaller the vent hole S, the greater the pressure P inside the tank.

[0005] However, the actual application situation is: in order to exhaust the gas in time during the refueling process, the vent hole S needs to be as large as possible; and for safety reasons, the valve needs to be able to open in time when the internal pressure P of the fuel tank is relatively large, that is, the larger P, the better. There is a situation where both P and S are required to be very large. How to achieve that when P is relatively large, the valve can be opened in time to exhaust the gas. At present, most of the designs of refueling limit valves on the market have only one-level opening capability. When the refueling limit valve is closed, the main exhaust of the system can only be through the rollover valve, and the refueling limit valve cannot be opened under high pressure. The pressure in the fuel tank system is always very high. If you want to refuel the vehicle again, you can only wait for the rollover valve to slowly reduce the pressure in the fuel tank. Therefore, in order to solve the above technical problems, the present invention provides a double-wall high-performance refueling limit valve. Summary of the invention

[0006] Purpose of the invention: In order to overcome the above shortcomings, the purpose of the present invention is to provide a double-wall high-performance refueling limit valve and its working method. The structural design is reasonable and the working method is simple. Through the two-stage opening mode of the valve, rapid opening and pressure reduction under high pressure conditions can be achieved, thereby improving the safety of the fuel tank and vehicle system. The double-wall structure is adopted to achieve zero dynamic leakage of liquid under dynamic conditions. The modular design achieves different closing heights to meet diverse needs and has broad application prospects.

[0007] Technical solution: A double-wall high-performance refueling limit valve, including a shell, a float assembly, and a bottom cover, wherein the shell is sleeved on the outside of the float assembly, the bottom cover is installed at the bottom of the shell and contacts the bottom of the float assembly through a spring; the float assembly includes a float shell, a sealing door, and a float, wherein the sealing door is assembled on the upper part of the float and is placed inside the float shell together with the float, the spring is installed between the bottom of the float and the bottom cover, and the float can move up and down in the float shell; a secondary opening vent hole is provided at the center of the upper end surface of the float shell, a primary opening vent hole is provided at the center of the sealing door, the aperture of the primary opening vent hole is smaller than the aperture of the secondary opening vent hole, a primary opening sealing plunger cooperating with the primary opening vent hole is provided at the center of the upper part of the float, the diameter of the primary opening sealing plunger is larger than the aperture of the primary opening vent hole and smaller than the aperture of the secondary opening vent hole; an oil hole is provided on the upper part of the shell, and a fine hole is provided at the bottom of the bottom cover.

[0008] The double-wall high-performance refueling limit valve described in the present invention has a reasonable structural design and adopts a two-stage opening mode in which a first-stage opening vent hole is coordinated with a second-stage opening vent hole, thereby realizing the ability of the refueling limit valve to quickly open and reduce pressure under high pressure conditions, and can exhaust air in time to eliminate the pressure in the fuel tank, reduce hidden dangers, improve the safety of the fuel tank and the vehicle system, and provide a re-refueling function.

[0009] In addition, an oil hole is provided on the upper part of the shell. During the refueling process, as the oil gradually rises, when the oil reaches the oil hole, that is, the closing window, the oil quickly flows into the shell through the oil hole of the shell. After the oil enters, the float quickly rises under the action of buoyancy, and the sealing door closes the vent. Therefore, the present invention can achieve different closing heights and different liquid level closing heights by simply replacing the shell with different oil hole heights. The other components do not need to be adjusted, and the modular design meets the diverse needs of customers. As the oil is used, the oil level drops, and the oil entering the shell flows out from the pores of the bottom cover.

[0010] Furthermore, in the above-mentioned double-wall high-performance refueling limiting valve, a double-wall structure is formed between the shell and the float shell, the top of the shell is welded to the upper end surface of the float shell, and the bottom of the shell is clamped to the bottom cover.

[0011] A double-wall structure is formed between the outer shell and the float outer shell of the present invention, thereby achieving zero dynamic leakage of liquid under dynamic conditions.

[0012] Furthermore, in the above-mentioned double-wall high-performance refueling limiting valve, an O-ring is provided on the outer side of the top of the upper end surface of the float housing.

[0013] By providing an O-ring, the sealing performance of the refueling limit valve installed on the fuel tank is improved.

[0014] Furthermore, in the above-mentioned double-wall high-performance refueling limiting valve, the aperture of the first-stage opening vent hole is 3-4mm, the aperture of the second-stage opening vent hole is 11-12mm, and the diameter of the first-stage opening sealing plunger is 7-8mm.

[0015] Furthermore, in the above-mentioned double-wall high-performance refueling limiting valve, the aperture of the first-stage opening vent hole is 3.5 mm, the aperture of the second-stage opening vent hole is 11.2 mm, and the diameter of the first-stage opening sealing plunger is 7.5 mm.

[0016] Furthermore, in the above-mentioned double-wall high-performance refueling limiting valve, the upper end surface of the sealing door is provided with a sealing gasket that cooperates with the first-level opening vent hole, and the diameter of the sealing gasket is 11-12 mm.

[0017] Furthermore, in the above-mentioned double-wall high-performance refueling limiting valve, the diameter of the sealing gasket is 11.8 mm.

[0018] Furthermore, in the above-mentioned double-wall high-performance refueling limiting valve, the float includes an upper float and a lower float, the upper float and the lower float are arranged from top to bottom and welded together, and the spring is installed between the bottom of the lower float and the bottom cover.

[0019] The present invention also relates to a working method of a double-wall high-performance refueling limit valve, the working method comprising the following steps:

[0020] (1) Refueling: During the refueling process, as the oil in the tank rises, when the oil reaches the oil hole, the oil flows into the outer shell through the oil hole of the outer shell. After the oil enters, the float rises rapidly under the action of buoyancy, and drives the sealing door to rise together until the first-level open vent hole and the second-level open vent hole are in the closed state. At this time, refueling is completed;

[0021] (2) Exhaust: The oil in the oil tank gradually decreases with use. The more oil vapor is generated in the oil tank, the greater the pressure in the oil tank. When the internal pressure of the oil tank system is the same, the area corresponding to the first-level open vent is small, and the area corresponding to the second-level open vent is large. The pressure corresponding to the first-level open vent is greater than the pressure corresponding to the second-level open vent. At this time, the first-level open vent is opened, and the oil vapor in the oil tank begins to be exhausted through the first-level open vent. The pressure corresponding to the first-level open vent in the oil tank begins to decrease, and the pressure remains unchanged. When the pressure corresponding to the first-level open vent in the oil tank drops to the pressure corresponding to the second-level open vent, the second-level open vent is opened to achieve large-flow exhaust.

[0022] (3) Refueling: The second-stage vent is opened to achieve large-flow exhaust. The pressure balance of the refueling limit valve is destroyed, and the refueling limit valve returns to its original free state, thereby providing the function of refueling.

[0023] The beneficial effects of the present invention are:

[0024] (1) The double-wall high-performance refueling limit valve of the present invention adopts a two-stage opening mode in which the first-stage opening vent hole and the second-stage opening vent hole cooperate with each other, so that the refueling limit valve can quickly open and reduce pressure under high pressure and strong pressure, and can exhaust gas in time, eliminate the pressure in the fuel tank, reduce hidden dangers, improve the safety of the fuel tank and vehicle system, and provide a refueling function;

[0025] (2) The double-wall high-performance refueling limit valve of the present invention can achieve different closing heights by simply replacing the outer shell with different oil hole heights, that is, different liquid level closing heights. The remaining components do not need to be adjusted. The modular design meets the diverse needs of customers.

[0026] (3) The double-wall high-performance refueling limit valve of the present invention forms a double-wall structure between the housing and the float housing, achieving zero dynamic leakage of liquid under dynamic conditions;

[0027] (4) The working method of the double-wall high-performance refueling limit valve described in the present invention has a reasonable design, is easy to operate, and has broad application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 This is a schematic diagram of the structure of the double-wall high-performance refueling limit valve of the present invention;

[0029] Figure 2 It is a schematic diagram of the assembly of the double-wall high-performance refueling limit valve of the present invention;

[0030] Figure 3 This is a schematic diagram of the structure of the float housing of the double-wall high-performance refueling limit valve of the present invention;

[0031] Figure 4 This is a schematic diagram of the sealing door structure of the double-wall high-performance refueling limiting valve of the present invention;

[0032] Figure 5 This is a schematic diagram of the float structure of the double-wall high-performance refueling limit valve of the present invention;

[0033] Figure 6 It is a structural schematic diagram of the double-wall high-performance refueling limiting valve of the present invention in a closed state;

[0034] Figure 7 It is a structural schematic diagram of the double-wall high-performance refueling limit valve of the present invention in a first-stage opening state;

[0035] Figure 8 It is a structural schematic diagram of the double-wall high-performance refueling limit valve of the present invention in a secondary opening state;

[0036] Fig. 9 This is a specific dimension diagram corresponding to the first-stage opening vent hole of the double-wall high-performance refueling limit valve of the present invention;

[0037] Fig.10 This is a specific dimension diagram corresponding to the first-stage opening and sealing plunger of the double-wall high-performance refueling limiting valve of the present invention;

[0038] Fig.11 This is a specific dimension diagram corresponding to the secondary opening vent hole of the double-wall high-performance refueling limit valve of the present invention;

[0039] Fig.12 This is a specific dimension diagram corresponding to the sealing gasket of the double-wall high-performance refueling limit valve of the present invention;

[0040] Fig.13 This is a cross-sectional view of the sealing gasket structure of the double-wall high-performance refueling limit valve of the present invention;

[0041] Fig.14 It is a cross-sectional view of the local structure of the float of the double-wall high-performance refueling limit valve of the present invention;

[0042] Fig.15 This is a schematic diagram of the double-wall high-performance refueling limiting valve of the present invention;

[0043] In the figure: housing 1, oil hole 11, float assembly 2, float housing 21, upper end surface 211, secondary opening vent 212, O-ring 213, sealing door 22, primary opening vent 221, sealing gasket 222, float 23, primary opening sealing plunger 231, upper float 232, lower float 233, bottom cover 3, fine hole 31, spring 4. DETAILED DESCRIPTION

[0044] The following is combined with Figure 1-15 And specific examples further illustrate the present invention.

[0045] In the description of the present invention, it is necessary to understand that the terms "upper", "lower", "front", "back", "left", "right", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0046] like Figure 1-15 The double-wall high-performance refueling limit valve of the above structure shown in the figure comprises a housing 1, a float assembly 2, and a bottom cover 3. The housing 1 is sleeved on the outside of the float assembly 2. The bottom cover 3 is installed at the bottom of the housing 1 and contacts the bottom of the float assembly 2 through a spring 4. The float assembly 2 comprises a float housing 21, a sealing door 22, and a float 23. The sealing door 22 is assembled on the upper part of the float 23 and is placed inside the float housing 21 together with the float 23. The spring 4 is installed between the bottom of the float 23 and the bottom cover 3. The float 23 can move up and down in the float housing 21. The float housing A secondary opening vent 212 is provided at the center of the upper end surface 211 of the sealing door 21, a primary opening vent 221 is provided at the center of the sealing door 22, the aperture of the primary opening vent 221 is smaller than the aperture of the secondary opening vent 212, a primary opening sealing plunger 231 is provided at the center of the upper part of the float 23 to match the primary opening vent 221, the diameter of the primary opening sealing plunger is larger than the aperture of the primary opening vent 221 and smaller than the aperture of the secondary opening vent 212; an oil hole 11 is provided at the upper part of the shell 1, and a fine hole 31 is provided at the bottom of the bottom cover 3.

[0047] Furthermore, a double-wall structure is formed between the housing 1 and the float housing 21 , the top of the housing 1 is welded to the upper end surface 211 of the float housing 21 , and the bottom of the housing 1 is snap-connected to the bottom cover 3 .

[0048] Furthermore, an O-ring 213 is disposed on the outer side of the top of the upper end surface 211 of the float housing 21 .

[0049] Furthermore, the aperture of the primary opening vent hole 221 is 3-4 mm, the aperture of the secondary opening vent hole 212 is 11-12 mm, and the diameter of the primary opening sealing plunger 231 is 7-8 mm.

[0050] Furthermore, the aperture of the primary opening vent hole 221 is 3.5 mm, the aperture of the secondary opening vent hole 212 is 11.2 mm, and the diameter of the primary opening sealing plunger 231 is 7.5 mm.

[0051] Furthermore, a sealing gasket 222 is provided on the upper end surface of the sealing door 22 to cooperate with the first-level opening vent hole 221, and the diameter of the sealing gasket 222 is 11-12 mm.

[0052] Furthermore, the diameter of the sealing gasket 222 is 11.8 mm.

[0053] Furthermore, the float 23 includes an upper float 232 and a lower float 233 , which are arranged from top to bottom and welded together, and the spring 4 is installed between the bottom of the lower float 233 and the bottom cover 3 . Example

[0054] Based on the above structural foundation, such as Figures 1 to 15 As shown, the working method of the double-wall high-performance refueling limit valve of the present invention comprises the following steps:

[0055] (1) Refueling: During the refueling process, as the oil in the fuel tank rises, when the oil reaches the oil hole 11, the oil flows into the housing 1 through the oil hole 11 of the housing 1. After the oil enters, the float 33 rises rapidly under the action of buoyancy, and drives the sealing door 22 to rise together, until the first-stage open vent 221 and the second-stage open vent 212 are in a closed state. At this time, refueling is completed;

[0056] (2) Exhaust: The oil in the oil tank gradually decreases with use. The more oil vapor is generated in the oil tank, the greater the pressure in the oil tank. When the internal pressure of the oil tank system is the same, since the area corresponding to the first-level open vent 221 is small and the area corresponding to the second-level open vent 212 is large, the pressure corresponding to the first-level open vent 221 is greater than the pressure corresponding to the second-level open vent 212. At this time, the first-level open vent 221 is opened, and the oil vapor in the oil tank begins to be exhausted through the first-level open vent 221. The pressure corresponding to the first-level open vent 221 in the oil tank begins to decrease, and the pressure remains unchanged. When the pressure corresponding to the first-level open vent 221 in the oil tank drops to the pressure corresponding to the second-level open vent 212, the second-level open vent 212 is opened to achieve large-flow exhaust.

[0057] (3) Refueling: The secondary opening vent hole 212 is opened to achieve large-flow exhaust, and the pressure balance of the refueling limit valve is destroyed. The refueling limit valve returns to its original free state, thereby providing a refueling function.

[0058] From the above, it can be seen that the double-wall high-performance refueling limit valve described in the present invention has a reasonable structural design, and adopts a two-stage opening mode in which the first-stage opening vent hole 221 is coordinated with the second-stage opening vent hole 212, thereby realizing the ability of the refueling limit valve to quickly open and reduce pressure under high pressure conditions, and can exhaust air in time to eliminate the pressure in the fuel tank, reduce hidden dangers, improve the safety of the fuel tank and the vehicle system, and provide a re-refueling function.

[0059] In addition, an oil hole 11 is provided on the upper part of the housing 1. During the refueling process, as the oil gradually rises, when the oil reaches the oil hole 11, that is, when the window is closed, the oil quickly flows into the housing 1 through the oil hole of the housing 1. After the oil enters, the float 23 quickly rises under the action of buoyancy, and the sealing door 22 closes the vent. Therefore, the present invention only needs to replace the housing 1 with different oil hole 11 heights to achieve different closing heights, that is, to achieve different liquid level closing heights. The remaining components do not need to be adjusted, and the modular design meets the diverse needs of customers. As the oil is used, the oil level drops, and the oil entering the interior of the housing 1 flows out from the pores 31 of the bottom cover 3.

[0060] Furthermore, the double wall structure is formed between the housing 1 and the float housing 21 of the present invention, so that the dynamic leakage of liquid is zero under dynamic conditions. By providing the O-ring 213, the sealing performance of the refueling limit valve installed on the oil tank is improved.

[0061] The preferred embodiments of the present invention are described in detail above in conjunction with the accompanying drawings. However, the present invention is not limited to the specific details in the above embodiments. Within the technical concept of the present invention, a variety of simple modifications can be made to the technical solution of the present invention, and these simple modifications all belong to the protection scope of the present invention.

[0062] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present invention will not further describe various possible combinations.

[0063] In addition, the embodiments of the present invention may be arbitrarily combined, and as long as they do not violate the concept of the present invention, they should also be regarded as the contents disclosed by the present invention.

Claims

1. A double-wall high-performance refueling limit valve, characterized in that: The invention comprises a housing (1), a float assembly (2), and a bottom cover (3), wherein the housing (1) is sleeved on the outside of the float assembly (2), the bottom cover (3) is mounted on the bottom of the housing (1) and contacts the bottom of the float assembly (2) via a spring (4); the float assembly (2) comprises a float housing (21), a sealing door (22), and a float (23), the sealing door (22) is mounted on the upper part of the float (23) and is placed inside the float housing (21) together with the float (23), the spring (4) is mounted between the bottom of the float (23) and the bottom cover (3), and the float (23) can move up and down inside the float housing (21); a secondary opening vent hole (212) is provided at the center of the upper end surface (211) of the float housing (21), a primary opening vent hole (221) is provided at the center of the sealing door (22), and the primary opening vent hole (221) is provided at the center of the sealing door (22). The diameter of the secondary opening vent hole (21) is smaller than that of the secondary opening vent hole (212); a primary opening sealing plunger (231) is arranged at the center of the upper part of the float (23) to match the primary opening vent hole (221); the diameter of the primary opening sealing plunger is larger than the diameter of the primary opening vent hole (221) and smaller than the diameter of the secondary opening vent hole (212); an oil hole (11) is arranged at the upper part of the shell (1), and a fine hole (31) is arranged at the bottom of the bottom cover (3); a double wall structure is formed between the shell (1) and the float shell (21); an O-ring (213) is arranged on the outer side of the top of the upper end surface (211) of the float shell (21); the diameter of the primary opening vent hole (221) is 3-4 mm, the diameter of the secondary opening vent hole (212) is 11-12 mm, and the diameter of the primary opening sealing plunger (231) is 7-8 mm.

2. The double-wall high-performance refueling limit valve according to claim 1 is characterized in that: The top of the housing (1) is welded to the upper end surface (211) of the float housing (21), and the bottom of the housing (1) is snap-connected to the bottom cover (3).

3. The double-wall high-performance refueling limit valve according to claim 1 is characterized in that: The aperture of the primary opening vent hole (221) is 3.5 mm, the aperture of the secondary opening vent hole (212) is 11.2 mm, and the diameter of the primary opening sealing plunger (231) is 7.5 mm.

4. The double-wall high-performance refueling limit valve according to claim 3 is characterized in that: The upper end surface of the sealing door (22) is provided with a sealing gasket (222) that cooperates with the first-stage opening vent hole (221), and the diameter of the sealing gasket (222) is 11-12 mm.

5. The double-wall high-performance refueling limit valve according to claim 4 is characterized in that: The diameter of the sealing gasket (222) is 11.8 mm.

6. The double-wall high-performance refueling limit valve according to claim 1 is characterized in that: The float (23) comprises an upper float (232) and a lower float (233), the upper float (232) and the lower float (233) are arranged from top to bottom and welded together, and the spring (4) is installed between the bottom of the lower float (233) and the bottom cover (3).

7. The working method of the double-wall high-performance refueling limit valve according to any one of claims 1 to 6, characterized in that: The working method comprises the following steps: (1) Refueling: During the refueling process, as the oil in the oil tank rises, when the oil reaches the oil hole (11), the oil flows into the outer shell (1) through the oil hole (11) of the outer shell (1). After the oil enters, the float (23) rises rapidly under the action of buoyancy, and drives the sealing door (22) to rise together, until the first-stage open vent hole (221) and the second-stage open vent hole (212) are in a closed state. At this time, refueling is completed; (2) Exhaust: The oil in the oil tank gradually decreases with use. The more oil vapor is generated in the oil tank, the greater the pressure in the oil tank. When the internal pressure of the oil tank system is the same, since the area corresponding to the first-level open vent hole (221) is small and the area corresponding to the second-level open vent hole (212) is large, the pressure corresponding to the first-level open vent hole (221) is greater than the pressure corresponding to the second-level open vent hole (212). At this time, the first-level open vent hole (221) is opened, and the oil vapor in the oil tank begins to be exhausted through the first-level open vent hole (221). The pressure corresponding to the first-level open vent hole (221) in the oil tank begins to decrease, and the pressure remains unchanged. When the pressure corresponding to the first-level open vent hole (221) in the oil tank drops to the pressure corresponding to the second-level open vent hole (212), the second-level open vent hole (212) is opened to achieve large-flow exhaust. (3) Refueling: The second-stage opening vent hole (212) is opened to achieve large-flow exhaust, and the pressure balance of the refueling limit valve is destroyed. The refueling limit valve returns to its original free state, thereby providing a refueling function.

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