Fuel tank isolation valve with upgraded housing

Abstract

The present invention provides a fuel tank isolation valve (100) with an upgraded housing (8) to ensure effective and appropriate sealing of the valve, prevent leakage of hydrocarbons / fuel from housing connectors and enhance performance, improve pressure drop within the valve, prevent loss due to continuous impact motion, and thus improve the overall efficiency of the fuel tank isolation valve (100). The upgraded housing (8) is provided with a uniform top surface which prevents collision of the upgraded housing (8) on the upper portion of the fuel tank isolation valve. The upgraded housing (8) comprises a connector having at least two terminals, and the at least two terminals are covered with a heat shrinkable sleeve that prevents leakage of hydrocarbons.

Description

TECHNICAL FIELD

[0001] The present invention relates to the field of fuel tank isolation valves. More particularly, the present invention relates to fuel tank isolation valves having an upgraded housing that prevents hydrocarbon leakage, ensures stable placement of the valve and enhances the performance of the valve. BACKGROUND

[0002] Fuel tank isolation valves are critical components in vehicle fuel systems that play a vital role in managing fuel vapors and maintaining pressure within the fuel tank within safe and controlled limits, contributing to emission control and vehicle safety. In vehicles, the fuel tank is a closed and pressurized system that regulates fuel vapors to the canister until the engine is started. As fuel vaporizes, it creates pressure within the tank. Maintaining this pressure is important to minimize emissions and prevent fuel leakage.

[0003] Fuel tank isolation valves are installed between the fuel tank and the canister as part of the evaporative emission control system. When the pressure within the tank exceeds certain limits, it opens automatically, in turn allowing excess vapors to flow to the canister for containment until it can be handled by the engine. If negative pressure or vacuum is created within the tank, such as during overnight cooling, the fuel tank isolation valve opens automatically to maintain pressure within the protective range. This prevents the tank from collapsing and allows fresh air to flow from the canister into the tank. During refueling, the fuel tank isolation valve is electrically actuated to allow fuel vapors to flow from the fuel tank to the canister, preventing fuel vapors from escaping into the atmosphere. Fuel tank isolation valves help control pressure within the fuel tank by managing tank ventilation.

[0004] Further, the installation of the valve is done on the nozzle area and due to the metal components, the major weight of the valve is in the housing area, which causes the hanging weight situation and stress on the shock mounts and due to this, the valve is subjected to constant jolting motion. When the vehicle is in motion, the valve is subjected to constant jolting motion, due to which the valve is subjected to stress on the mounting flange.

[0005] WO2004 / 087452 discloses a system for controlling evaporative emissions of volatile fuel, the system comprising a fuel tank with a refueling pipe, a fuel tank isolation valve. The fuel tank isolation valve comprises a housing, a diaphragm and an actuator. The housing comprises a first port and a second port in communication with fuel vapors of the fuel tank. The diaphragm is movable relative to the housing between a first configuration and a second configuration. The first configuration prevents fuel vapors from flowing between the first port and the second port, and the second configuration allows fuel vapors to flow between the first port and the second port. Further, the actuator in fluid communication with the refueling pipe acts on the diaphragm. However, the system cannot provide a solution to prevent leakage of hydrocarbons from the housing connector and the system also cannot prevent the hanging weight situation and stress on the mounting flange.

[0006] Therefore, there is a need for a fuel tank isolation valve with an upgraded housing. SUMMARY

[0007] It is a primary object of the present invention to provide a fuel tank isolation valve with an upgraded housing that includes improved connectors that prevent hydrocarbon leakage.

[0008] It is another object of the present invention to provide a fuel tank isolation valve with an upgraded housing wherein the improved connectors have improved heat shrink terminal sleeves that provide better snugness and adhesion to the terminals.

[0009] It is yet another object of the present invention to provide a fuel tank isolation valve without any stopper that eliminates the top portion collision on the upper portion of the fuel tank isolation valve.

[0010] It is yet another object of the present invention to provide a fuel tank isolation valve wherein the absence of stopper reduces the obstruction of flow path and thus improves the flow resistance or pressure drop within the valve.

[0011] It is yet another object of the present invention to provide a fuel tank isolation valve with an upgraded housing that includes a retainer fitted in the housing that eliminates the problem of hanging weight condition and stress on the mounting flange.

[0012] It is yet another object of the present invention to provide a fuel tank isolation valve wherein the vibration impact is cushioned with the retainer which avoids the hanging weight condition.

[0013] The present invention relates to a fuel tank isolation valve with an upgraded housing that eliminates the leakage of hydrocarbons and eliminates the problem of hanging weight condition and stress on a pair of shock mounts of the valve.

[0014] In an embodiment, the present application provides a fuel tank isolation valve with upgraded housing. The upgraded housing is manufactured without stopper in the top portion and the removal of the stopper eliminates the collision of the top portion on the upper portion of the fuel tank isolation valve. Also, the removal of the stopper reduces the obstruction from the flow path and hence improves the flow resistance or pressure drop within the valve. Further, the upgraded housing includes heat shrink sleeve for at least two terminals of the fuel tank isolation valve. Further, the heat shrink sleeve provides better snugness and adhesion with the two terminals. Also, the heat shrink sleeve is preferably end seal lug type which prevents the leakage of hydrocarbons from the housing connector and enhances the performance of the valve. Further, the fuel tank isolation valve also includes retainer fitted in the upgraded housing which eliminates the problem of hanging weight condition and stress on the shock mounts and holds / secure the fuel tank isolation valve in stable position thereby improving the operational reliability of the fuel tank isolation valve.

[0015] The above objects and advantages of the present application will become clear from the following detailed description, taken in conjunction with the accompanying drawings, which illustrate, by way of example, the principles of the application. BRIEF DESCRIPTION OF DRAWINGS

[0016] An understanding of the fuel tank isolation valve with upgraded housing of the present application can be obtained in light of the following detailed description in connection with the accompanying drawings, in which:

[0017] Figure 1 is an exploded view of the fuel tank isolation valve with upgraded housing according to an embodiment of the present application;

[0018] Figure 2 shows a perspective view of the upgraded housing according to an embodiment of the present application;

[0019] Figure 3 shows a perspective view of the retainer according to an embodiment of the present application;

[0020] Figure 4 shows a perspective view of the heat shrink sleeve of the upgraded housing according to an embodiment of the present application; and

[0021] Figure 5 shows a perspective view of the fuel tank isolation valve with upgraded housing according to an embodiment of the present application. DETAILED DESCRIPTION

[0022] The present application will now be described hereinafter with reference to the accompanying drawings, in which the preferred embodiments of the application are shown. The application may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the application to those skilled in the art.

[0023] Many aspects of the application can be better understood with reference to the following drawings. The components in the drawings are not necessarily to scale. Instead, emphasis is placed on clearly illustrating the components of the present application. Furthermore, like reference numerals designate corresponding parts throughout the several views of the drawings. Before at least one embodiment of the application is explained in detail, it is to be understood that embodiments of the application are not limited in their application to the details of construction and the arrangement of the components set forth in the following description or illustrated in the drawings. Embodiments of the application are capable of being practiced or carried out in various ways. Also, the phraseology and terminology employed herein are for the purpose of description and should not be regarded as limiting.

[0024] The present application provides a fuel tank isolation valve having an upgraded housing comprising an improved heat shrink sleeve which has better snugness and adhesion with the terminals and prevents leakage of hydrocarbons from the housing connectors which enhances the performance of the valve.

[0025] In a preferred embodiment, the present application provides a fuel tank isolation valve having an upgraded housing. The upgraded housing is manufactured without a stopper at the top portion and the removal of the stopper eliminates the collision of the top portion on the upper section of the fuel tank isolation valve. Also, the removal of the stopper reduces the obstruction from the flow path and thus improves the flow resistance or pressure drop inside the valve. Further, the upgraded housing comprises a heat shrink sleeve for at least two terminals of the fuel tank isolation valve. Further, the heat shrink sleeve provides better snugness and adhesion with the two terminals. Also, the heat shrink sleeve is preferably of end seal lug type which prevents leakage of hydrocarbons from the housing connectors and enhances the performance of the valve. Further, the fuel tank isolation valve also comprises a retainer fitted in the upgraded housing which eliminates the problem of hanging weight condition and stress on the shock mounts and holds / secure the fuel tank isolation valve in a stable position thereby improving the operational reliability of the fuel tank isolation valve.

[0026] Referring to Figure 1 , depicts an exploded view of a fuel tank isolation valve having an upgraded housing according to an embodiment of the present application. The fuel tank isolation valve (100) comprises a cap (1), a pressure spring (2), a pair of torque limiters (3), an inlet and outlet nozzle (4), a seal (5), a seal retainer (6), a vacuum spring (7), an upgraded housing (8), a silencer (9), a moving core (10), a pair of shock mounts (11), a flow restrictor (12), and a travel limiter (13).

[0027] Referring to Figure 2, depicts a perspective view of the upgraded housing 8 of the fuel tank isolation valve. The upgraded housing (8) partially encases the valve such that the nozzle portion of the valve (100) is above the housing (8) for mounting the valve and the major weight of the valve is within the housing (8). The major weight of the fuel tank isolation valve (100), i.e. the metal components, includes the solenoid components. Therefore, approximately 60-70% of the weight of the solenoid components of the fuel tank isolation valve 100 is contained within the upgraded housing (8). Furthermore, the upgraded housing (8) is configured without any stopper at the top of the housing, thus eliminating its probability of deterioration during its lifetime due to repeated impact of the moving plunger (moving core) and thus increasing the shelf life of the valve. The installation of the fuel tank isolation valve (100) includes fastening the valve (100) assembly in a specific position of the upgraded housing (8) to ensure proper functioning, accessibility, and safety of the valve (100). This installation enables the valve (100) to be securely fixed in the required area and in the required position for the desired performance.

[0028] Referring to Figure 3 , depicts a perspective view of the retainer (14) according to an embodiment of the present application. The retainer (14) herein fits over the housing (8) to cushion the impact of vibrations and to avoid the hanging weight situation when it rests on the mating surface of the vehicle. The retainer (14) is preferably made of rubber, which acts as a shock absorber, thereby reducing the transmission of vibrations and mechanical impacts to the valve (100). This cushioning action helps to protect the fuel tank isolation valve (100) components from damage caused by mechanical stresses, vibrations during operation or transportation.

[0029] Referring to Figure 4 , depicts a perspective view of the heat shrink sleeve (16) of the upgraded housing connector of the fuel tank isolation valve. The heat shrink sleeve (16) includes two terminals (17), each of which is sealed by a rubber component that is a compressed material, thereby sealing the terminals of the connector of the housing (8) by the barrel (15). This sealing presents an improved adhesion to the terminals and improved snugness, thus preventing the leakage of hydrocarbons from the valve (100). The rubber component used herein is inserted over the terminals. The rubber component is essentially compressed with a heat gun. When the heat gun is applied over the rubber component, the rubber component is squeezed and adhered to the terminals and prevents more fuel discharge. This arrangement of the rubber component with the terminals (17) of the housing connector provides a robust solution for preventing the discharge of hydrocarbons from the valve (100).

[0030] Referring to Figure 5depicts a perspective view of a fuel tank isolation valve having an upgraded housing (8) mounted on the surface of the vehicle. The fuel tank isolation valve (100) is divided into multiple parts, the upper part of the fuel tank isolation valve (100) which mates with the nozzle is made of plastic component, the lower part of the fuel tank isolation valve (100) which is the lower part of the fuel tank isolation valve (100) contains the solenoid component. The upgraded housing (8) encases the lower part of the valve (100), rests on the mating surface of the vehicle to avoid the hanging weight condition, and the upper part of the valve (100) includes the nozzle for effective transfer of fuel to the filter canister of the vehicle engine.

[0031] Example 1

[0032] Implementation of fuel tank isolation valve with upgraded housing

[0033] The present invention provides a fuel tank isolation valve (100) with an upgraded housing, wherein the upgraded housing (8) is provided with a uniform top surface which eliminates the impact of the upgraded housing (8) on the upper part of the fuel tank isolation valve (100). This eliminates the probability of rubber degradation due to repeated impact of the stopper during the life time. This also reduces the obstruction from the flow path and hence improves the flow resistance or pressure drop inside the fuel tank isolation valve (100).

[0034] Further, the heat shrink sleeves on both terminals eliminate the leakage of hydrocarbons and have good grip and adhesion with both terminals. Also, the heat shrink sleeves have an elongated tubular rigid structure. These heat shrink sleeves reduce the leakage of hydrocarbons.

[0035] Further, the retainer (14) fitted in the upgraded housing (8) eliminates the problem of stress on the hanging weight condition and a pair of shock mounts (11) and holds the fuel tank isolation valve (100) in a stable position, thereby improving the operational reliability of the fuel tank isolation valve (100). The retainer (14) comprises a pair of triangular bracket shaped segments having a circular opening in the middle region and has a reinforced segment which facilitates holding the fuel tank isolation valve in a stable position.

[0036] The retainer (14) reduces the transmission of vibrations and mechanical shocks on the pair of shock mounts (11).

[0037] Thus, the present invention provides a fuel tank isolation valve with an upgraded housing, thereby ensuring effective and proper sealing of the valve, preventing leakage of hydrocarbons / fuel from the housing connector and enhancing the performance, improving the pressure drop inside the valve, preventing loss due to continuous impact motion and hence improving the overall efficiency of the fuel tank isolation valve.

[0038] Many modifications and other embodiments of the inventions set forth herein will come to mind to one skilled in the art to which these inventions pertain having the benefit of the teachings presented in the foregoing descriptions and the associated drawings. Therefore, it is to be understood that the inventions are not to be limited to the specific embodiments disclosed and that modifications and other embodiments are intended to be included within the scope of the appended claims. Although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation.

[0039] The foregoing description of embodiments of the invention has been presented for the purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form disclosed, and modifications and variations are possible in light of the above teachings or can be acquired from practice of the invention. The embodiments were chosen and described in order to explain the principles of the invention and its practical application and to enable others skilled in the art to utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated.

Claims

1. A fuel tank isolation valve with an upgraded housing, the fuel tank isolation valve comprising: a cap (1); a pressure spring (2); a pair of torque limiters (3); inlet and outlet nozzles (4); a seal (5); a seal retainer (6); a vacuum spring (7); an upgraded housing (8); a silencer (9); a moving core (10); a pair of shock absorbing mounts (11); a flow restrictor (12); and a travel limiter (13); wherein: the upgraded housing (8) is provided with a uniform top surface that prevents the upgraded housing (8) from colliding on the upper portion of the fuel tank isolation valve; the upgraded housing (8) comprises a connector having at least two terminals (17), and each of the at least two terminals (17) is covered with a hydrocarbon leakage eliminating heat shrink sleeve (16); and the fuel tank isolation valve is provided with a retainer (14) that is fitted in the upgraded housing (8), the retainer (14) eliminates the problem of the suspended weight situation and stress on the pair of shock absorbing mounts (11), and holds the fuel tank isolation valve in a stable position, thereby increasing the operational reliability of the fuel tank isolation valve.

2. The fuel tank isolation valve with upgraded housing of claim 1, wherein, the upgraded housing (2) comprises the pressure spring (2) that is fixed above the flow restrictor (12).

3. The fuel tank isolation valve with upgraded housing of claim 1, wherein, the flow restrictor (12) is placed below the travel limiter (13).

4. The fuel tank isolation valve with upgraded housing of claim 1, wherein, the cap (1) is fastened above the upgraded housing (2).

5. The fuel tank isolation valve with upgraded housing of claim 1, wherein, the retainer (14) cushions the vibrational impact on the mating surface of the vehicle, the retainer (14) eliminates the problem of the suspended weight situation and stress on the pair of shock absorbing mounts (11).

6. The fuel tank isolation valve with upgraded housing of claim 1, wherein, the retainer (14) is made of rubber, the retainer (14) acts as a shock absorber for reducing the transmission of vibrations and mechanical impacts to the fuel tank isolation valve.

7. The fuel tank isolation valve with upgraded housing of claim 1, wherein, the retainer (14) reduces the transmission of vibrations and mechanical impacts on the pair of shock absorbing mounts (11).

8. The fuel tank isolation valve with upgraded housing of claim 1, wherein, the heat shrink sleeve (16) is made of a material including rubber, plastic.

9. The fuel tank isolation valve with upgraded housing of claim 1, wherein, the heat shrink sleeve (16) reduces the leakage of hydrocarbons.

10. The fuel tank isolation valve with upgraded housing of claim 1, wherein, the retainer (14) comprises a pair of triangular bracket-shaped sections having a circular opening in the middle region, and the retainer has a reinforced section that facilitates holding the fuel tank isolation valve in a stable position.

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