FUEL TANK CONTROL UNIT FOR A VEHICLE

FIELD OF THE INVENTION

The present invention relates to the fuel tank unit of a vehicle and more particularly to an improved fuel tank control unit, used in two-wheelers and three- wheelers.

BACKGROUND OF THE INVENTION

Vehicles with an internal combustion engine have a fuel tank for storing fuels like petrol, diesel, LPG (Liquefied Petroleum Gas) and CNG (Compressed Natural Gas). Fuel tanks for liquid fuels like petrol and diesel commonly have a fuel cock unit for controlling the fuel flow between fuel tank and the engine. The fuel cock unit commonly has a manually controllable knob for changing the state of fuel cock. The knob can either set the fuel cock in ON position, OFF position or RESERVE position. With the knob in ON position, fuel is allowed to flow from tank to engine until the fuel level reaches a RESERVE condition. Once the fuel level reaches a RESERVE condition, fuel can no longer flow from tank to engine and the user recognizes that the fuel level has dropped to a low level. Thereafter, the rider can change the knob position to a RESERVE position and fuel flow between tank and engine continues until the fuel level reaches EMPTY condition. The rider can also choose to shut-off fuel flow between " " tank and engine by setting the fuel cock knob in OFF position. Further the fuel cock unit is also provided with a fuel strainer to filter the fuel supplied to the engine.

Fuel tanks unit for liquid fuels also commonly employ a fuel sensor unit for providing a signal that is indicative of fuel level to the rider. Typically, the fuel cock unit, a fuel sensor unit and a fuel strainer are mounted to the fuel tank unit separately and at different mounting locations. Such kind of arrangement of the fuel tank unit leads to increased part counts and manufacturing cost, as the fuel sensor, the fuel cock, and the fuel strainer are mounted as separate units on the fuel tank. Further, the manufacturing of fuel tank for such kind of mounting arrangement is also difficult, as the fuel tank is to be provided with plurality of openings and different mounting locations for mounting different parts. Therefore, it is an objective of the present invention to substantially eliminate defects encountered in the prior art as mentioned above and to provide a fuel tank assembly for a motorcycle, which permits the mounting of fuel sensor unit, the fuel cock unit and the fuel strainer through a single recess.

SUMMARY OF THE INVENTION

The present invention relates to a fuel tank assembly for two wheelers and three wheelers, wherein said fuel tank assembly receives the mounting of a fuel tank control unit including an integrated strainer unit and a fuel cock unit through a single recess. Pursuant to the present invention, the fuel tank control unit including an integrated strainer unit and a fuel cock unit is detachably mounted to a recess provided at a fuel tank bottom portion. Accordingly, a mounting plate integrally formed with the fuel cock unit is detachably mounted to the recess provided in the fuel tank bottom portion and thereafter, an integrated strainer unit containing at least one sensor element and at least one strainer element is inserted into a central aperture of said mounting plate. While the sensor elements are disposed between slots provided in the integrated strainer unit, the strainer elements are disposed in the plurality of openings provided in said integrated strainer unit. Furthermore, the integrated strainer unit is inserted into the central aperture of said mounting plate by coaxially locating a bottom portion of the integrated strainer unit around a pipe disposed in the same central aperture.

Thus, the fuel tank control unit as per the present invention performs the functions of a fuel sensor, a fuel strainer and a fuel cock unit as a single entity and thereby aids in eliminating the need for having different mounting locations for different parts of the fuel tank assembly, and thus aids in reducing manufacturing costs and time. The foregoing objective and summary provide only a brief introduction to the present invention. To fully appreciate these and other objects of the present invention as well as the invention itself, all of which will become apparent to those skilled in the art, the following detailed description of the invention and the claims should be read in conjunction with the accompanying drawings. Throughout the specification and drawings identical reference numerals refer to identical or similar parts.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 illustrates a typical motorcycle with a fuel tank assembly.

Figure 2 illustrates a cross sectional view of a fuel tank assembly in accordance to the present invention.

Figure 3 illustrates a detailed view of fuel tank bottom portion, to which fuel tank control unit is mounted, in accordance to the present invention.

Figure 4 illustrates an exploded view of the fuel tank control unit in accordance to the present invention.

Figure 5 illustrates an exploded view of the integrated strainer unit in accordance to the present invention.

Figure 6 illustrates a perspective view of a fuel cock unit in accordance to the present invention.

DETAILED DESCRIPTION OF THE INVENTION

Exemplary embodiments of a fuel tank assembly comprising a fuel tank control unit in accordance to the present invention will be described hereunder with reference to the accompanying drawings. Various features of the fuel tank control unit in accordance to the present invention will become discernible from the following description set out hereunder. Rather, the following description provides a convenient illustration for implementing exemplary embodiments of the invention. It is to be noted that terms "upper", "lower", "right", "left", "front", "rear", "downward", "upward", "top", "bottom" and like terms are used herein based on the illustrated state or in a standing state of the vehicle with a driver riding thereon. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. Further, it is to be noted that while the present invention has been exemplified for a two wheeled vehicle, the invention can also be applied to a three wheeled vehicle. It is also to be noted that only the essential features of the invention have been described and description of other non essential features have been left out.

Referring to Figure 1, the layout of a typical motorcycle 1 with a fuel tank assembly 30 is elaborated. The motorcycle 1 includes a body frame 10 supporting an engine unit 20, a seat 24, a front wheel 25, a rear wheel 27. A head pipe 14 is provided at a front end of the body frame 10. The head pipe 14 supports a steering shaft (not shown) rotatably in a certain range and a front fork 16 pivotally. In an upper portion of the head pipe 14, a handlebar 15 is rotatably integrally connected to the steering shaft (not shown). A front wheel 25 is journaled to a lower end of the front fork 16 and the front wheel 25 is rotated in a certain range by steering the handlebar 15. A front lower portion of the body frame 10 supports the engine unit 20. The engine unit 20 is equipped with an exhaust system and includes an exhaust pipe (not shown) connected to the engine unit 20 and a muffler (not shown) connected to the exhaust pipe. The muffler extends rearwards along the right side of the rear wheel 27.

Power from the engine unit 20 suspended in a front lower portion of the body frame 10 is transmitted to the rear wheel 27 through a power drive mechanism, such as a drive chain, so as to drive and rotate the rear wheel 27. A rear fender 32 for covering the upper side of the rear wheel 27 is mounted to the rear portion of body frame 10 and a front fender 35 for covering the upper side of the front wheel 25 is mounted to the front fork 16. In a front portion of the body frame 10, the fuel tank assembly 30 is arranged immediately behind the handle bar 15 and is disposed over the engine unit 20. The fuel tank assembly 30 includes a fuel tank control unit (not shown) at its bottom portion. Further, a fuel cock unit 50 is disposed below the fuel tank assembly 30 for controlling the amount of fuel supplied to the engine unit 20 through a carburettor (not shown), wherein the fuel cock unit 50 forms a part of the fuel tank control unit (not shown). . ...

A cross sectional view of the fuel tank assembly 30 in accordance to the present invention is illustrated by Figure 2. As may be seen in the Figure, the fuel tank assembly 30 comprises a fuel tank top portion 30a and a fuel tank bottom portion 30b. An external fuel filler opening 42 is formed on the fuel tank top portion 30a and a fuel tank cap 45 is provided to enclose the same. Further, a fuel tank control unit 60 is mounted at the fuel tank bottom portion 30b. Figure 3 is a detailed view of the fuel tank bottom portion 30b, showing the mounting of the fuel tank control unit 60 to the fuel tank bottom portion 30b. The fuel tank control unit 60 is detachably mounted to a recess (not shown) provided in the fuel tank bottom portion 30b through a mounting plate 50a and by means of fasteners 51. Further, the fuel tank control unit 60 is mounted to the fuel tank bottom portion 30b in such a way that, a portion of the fuel tank control unit, which is disposed above the mounting plate 50a, is located inside the fuel tank assembly 30 and a second portion of the fuel tank control unit, which is disposed below the mounting plate 50a, is located outside the fuel tank assembly 30.

Thus, while one portion of the fuel tank control unit 60 remains inside the fuel tank assembly 30, the second portion of the fuel tank control unit 60 remains outside the fuel tank assembly 30. In the present embodiment, an integrated strainer unit of said fuel tank control unit remains inside the fuel tank assembly, while a fuel cock unit of said fuel tank control unit remains outside the fuel tank assembly. Figure 4 illustrates an exploded view of the fuel tank control unit 60 according to the present invention. As per the present invention, the fuel tank control unit 60 is formed by coupling an integrated strainer unit 140 with a fuel cock unit 50, such that the fuel cock unit 50 lies gravitationally downward of a bottom portion 140a of the integrated strainer unit 140. In the present embodiment the integrated strainer unit 140 integrally includes a fuel sensor 43 and a fuel strainer 39, wherein the fuel sensor 43 includes sensor elements such as a reed switch module 43a and a magnetic float 43b and the fuel strainer 39 includes strainer elements such as a filter gauze or filter net. Further, the integrated strainer unit 140 is mounted to the mounting plate 50a by coaxially locating a bottom portion 140a around a pipe 100, disposed in a central aperture provided in the mounting plate 50a.

In the present embodiment the mounting plate 50a is integrally formed with the fuel cock unit 50. Thus, the integrated strainer unit 140 integrally containing the fuel sensor 43 and the fuel strainer 39 is connected with the fuel cock unit 50, thereby integrating the fuel sensor 43, fuel strainer 39 and the fuel cock unit 50 as a single unit. The detailed construction of the integrated strainer unit 140 is elaborated with reference to Figure 5. As may be seen in the figure, the integrated strainer unit 140 is an elongated member with an intermediate body 140b and a bottom portion 140a integrally formed at a lower portion therein. The intermediate body 140b is disposed above and along the longitudinal axis of the bottom portion 140a. Further, a plurality of openings 150 is provided peripherally and along the length of the intermediate body 140b to receive the fuel strainer 39, which aids in filtering impurities from the fuel flowing from the fuel tank assembly 30 into the fuel cock unit 50. Further, slots 140c and 140d are disposed peripherally on the intermediate body 140b to receive the sensor elements such as reed switch module 43a and magnetic float 43b of the fuel sensor 43. Furthermore, said sensor elements are disposed in such a way that the magnetic float 43b is capable of moving along the slot 140c and adjacent to the reed switch module 43a disposed there between.

A cap 200 is provided at a top side of the intermediate body 140b to prevent the magnetic float 43b from sliding out. Thus, the construction of the integrated strainer unit 140 aids in holding the fuel sensor 43 and the fuel strainer 39 together as an integrated unit. In the present embodiment the integrated strainer unit 140 and the cap 200 and are preferably made of a polymer such as Nylon-66. The fuel sensor 43 integrally contained in the integrated strainer unit 140 aids in sensing the fuel level inside the fuel tank assembly 30. The magnetic float 43b comprising a permanent magnet within, is made of a material less dense than the fuel, so that the magnetic float 43b is always capable of floating above the fuel level. As the magnetic float 43b moves along the slot 140c corresponding to the fuel level inside the fuel tank assembly 30, a magnetic field is created around the float 43b. When the reed switch module 43a comes within the magnetic field created by the magnetic float 43b, it changes state depending upon the intensity of magnetic field generated by the magnetic float 43b. The change in state of the reed switch module 43a acts as an indication of the changing fuel level inside the fuel tank assembly 30. In the present embodiment, a single reed switch module 43a is positioned between the slots 140c and 140d. However, since the resolution of fuel level indication is dependent on the number of reed switch modules disposed in a sensor unit, in another embodiment, the number of reed switch modules disposed maybe increased by increasing the length of the intermediate body 140b of the integrated strainer unit 140, in order to obtain a higher resolution of fuel level indication.

Wiring harness 210 (shown in Fig 4) connects said reed switch module 43b to an external fuel indication circuit for indicating the fuel level either by analog or by digital means. In the present embodiment, the permanent magnet contained within the magnetic float 43b is preferably made of ferrite or NdFeB (Neodymium Iron Boron) material. Further, a detailed construction of the fuel cock unit 50 is elaborated with reference to Figure 6. As may be seen in the figure, the fuel cock unit 50 comprises an integrally formed mounting plate 50a with three apertures, one central aperture and two side apertures. While the two side apertures receive fasteners 51 (shown in Fig 3), the central aperture having an outer diameter 130a and an inner diameter 130b smaller than the outer diameter, such that the inner diameter 130b receives the pipe 100 having a thickness approximately equivalent to the inner diameter. Further, the inner diameter 130b is disposed in such a way that a cavity 130c is formed adjacent to the inner diameter 130b. Furthermore, the pipe 100 is disposed in such a way that an opening 100a of the pipe opens into the integrated strainer unit 140, and another opening (not shown), opens into a main inlet 110 of the fuel cock unit 50.

A manually controllable knob 90 for changing the state of the fuel cock unit 50 is also provided, which enables to set the fuel cock unit 50 either in ON position, OFF position or RESERVE position. In an assembled condition of the fuel tank control unit 60 in the fuel tank bottom portion 30b, that is when the integrated strainer unit 140 is coupled • to the fuel cock unit 50, the fuel from the fuel tank assembly 30 flows through the integrated strainer unit 140, and then through the pipe 100 located between the integrated strainer unit 140 and the fuel cock unit 50 and finally into the main inlet 110 of the fuel cock unit 50. This is the flow path of the fuel when the fuel level is above the opening 100a of the pipe 100 and when the knob 90 of the fuel cock unit 50 is in ON position. In this condition the flow of fuel to an outlet 120 of the fuel cock unit 50 is unrestricted. However, when the level of fuel falls below the opening 100a of the pipe 100, the fuel does not flow through the path described above. Rather, the fuel flows through the cavity 130c formed within the central aperture of the mounting plate 50a, wherein the cavity 130c acts as the reserve inlet of the fuel cock unit 50.

Thus, when the level of fuel inside the fuel tank unit 30 falls below the opening 100a of the pipe 100 and when the knob 90 of the fuel cock unit is set at RESERVE position, the fuel directly begins to flow into the carburettor through the reserve inlet of the fuel cock unit 50. While the fuel flow to the carburettor is controlled through the above mentioned parts of the fuel tank control unit 60, at the same time fuel sensor 43 disposed in the integrated strainer unit 140, sends signals corresponding to the fuel level inside the fuel tank assembly 30 to the external fuel indication circuit. Thus, the fuel tank control unit 60 mounted to the fuel tank bottom portion 30b aids not only in indicating fuel level inside the tank but also aids in controlling the fuel flow to the carburettor. Moreover, the fuel tank control unit 60 also filters the impurities in the fuel through the fuel strainer 39 disposed therein. Thus, the fuel tank control unit 60 performs three different functions as a single unit, thereby eliminating the need for a separate fuel sensor, a separate fuel strainer and a separate fuel cock unit.

As a result, the need for providing separate mounting platforms for a fuel sensor, a fuel strainer and a fuel cock unit is eliminated, thereby aiding in reducing the complexity of fuel tank assembly. While the present invention has been shown and described with reference to the foregoing preferred embodiments, it will be apparent to those skilled in the art that changes in form, connection, and detail may be made therein without departing from the spirit and scope of the invention as defined in the appended claims.

NE CLAIM:

1. An integrated strainer unit (140) for a fuel tank assembly (30) of a vehicle, said integrated strainer unit (140) comprising: a bottom portion (140a); and an intermediate body (140b) disposed substantially above and along a longitudinal axis of said bottom portion (140a); said intermediate body (140b) comprising: a plurality of openings (150) disposed peripherally on said intermediate body (140b), said plurality of openings (150) capable of accommodating one or more strainer elements for filtering impurities from fuel entering a fuel cock unit (50) disposed gravitationally downward of said bottom portion (140a); and one or more slots (140c and 140d) disposed peripherally on said intermediate body (140b), said one or more slots (140c and 140d) capable of receiving at least one sensor element for determining fuel level inside said fuel tank assembly (30).

2. The integrated strainer unit (140)as claimed in ciaim 1, wherein the bottom portion (140a) is coupled to a mounting plate (50a) integrally formed with the fuel cock unit (50), by coaxially locating said bottom portion (140a) around a pipe (100) disposed in the mounting plate (50a).

3. The integrated strainer unit (140) as claimed in claim 1, wherein the intermediate body (140b) receives a cap (200) from a top side to prevent slipping of said sensor element from the top side.

4. The integrated strainer unit (140) as claimed in claim 1, wherein the integrated strainer unit (140) is disposed inside said fuel tank assembly (30).

5. A fuel tank control unit (60) for a fuel tank assembly (30) of a vehicle, said fuel tank control unit (60) comprising: an integrated strainer unit (140); and a fuel cock unit (50) for controlling flow of fuel between said fuel tank assembly (30) and an engine unit of said vehicle.

6. The fuel tank control unit (60) as claimed in claim 5, wherein the integrated strainer unit (140) comprises: a bottom portion (140a); and an intermediate body (140b) disposed substantially above and along a longitudinal axis of said bottom portion (140a); said intermediate body (140b) comprising: a plurality of openings (150) disposed peripherally on said intermediate body (140b), said plurality of openings (150) capable of accommodating one or more strainer elements for filtering impurities from fuel entering the fuel cock unit (50) disposed gravitationally downward of said bottom portion (140a); and one or more slots (140c and 140d) disposed peripherally on said intermediate body (140b), said one or more slots (140c and 140d) capable of receiving at least one sensor element for determining fuel level inside said fuel tank assembly (30).

7. The fuel tank control unit (50) as claimed in claim 5, wherein the fuel cock unit (50) comprises an integrated mounting plate (50a) to receive the mounting of said integrated strainer unit (140).

8. The fuel tank control unit (50) as claimed in claim 7, wherein the mounting plate (50a) including an aperture having an outer diameter (130a) and an inner diameter (130b) smaller than said outer diameter (130a) for allowing the passage of a pipe (100) having a thickness substantially equivalent to that of said inner diameter (130b), and wherein a cavity (130c) is formed adjoining said inner diameter (130b).

9. The fuef tank control unit (60) as claimed in claim 8, wherein the * pipe (100) comprising an opening (100a) located in the integrated strainer unit (140) for allowing the passage of fuel through said opening (100a) to the fuel cock unit (50) when the level of fuel inside said fuel tank assembly (30) is above said opening (100a), and wherein the passage of fuel from said fuel tank assembly (30) to the fuel cock unit (50) is through the cavity (130c) when the level of fuel inside said fuel tank assembly (30) is below said opening (100a). 10. A fuel tank assembly (30) for a vehicle, said fuel tank assembly (30) comprising an integrated strainer unit (140) as claimed in claim 1 and a fuel tank control unit (60) as claimed in claim 5.