FIELD OF THE INVENTION

[001] The present invention relates to a fuel tank and, more particularly to, a fuel tank breathing system for a vehicle.
BACKGROUND

[002] Generally, a two-wheeled vehicle is provided with a fuel unit in the fuel tank which measures the fuel level in the fuel tank. A fuel float and electrical components indicate the amount of fuel in the fuel tank.
[003] Usually the fuel of the two-wheeled vehicle is either petrol or diesel, which is volatile in nature and tends to evaporate easily, resulting into generation of fuel fume inside the fuel tank. So a separate provision, for releasing the fuel fumes out of the fuel tank is provided in the form of an opening or a tube. Such a tube carries the fumes and supplies it to an evaporative system or a canister. The canister containing carbon is used for adsorbing the fuel fumes. In a conventional system, fuel tank breathes through the same canister and the tube.
[004] However, such systems incorporate additional components such as breathing tubes and hence are costly.
SUMMARY
[005] In an embodiment, a fuel tank breathing system in a two-wheeled vehicle is disclosed. The fuel tank breathing system includes a fuel float and an oscillating member. The fuel float is of a hollow configuration and positioned in a fuel tank of the two-wheeled vehicle for floating over the fuel present in the fuel tank. The fuel float includes a hole exposed to an inside space of the fuel tank. The oscillating member is coupled with the fuel float and is adapted to rotate based on a fuel level of the fuel present in the fuel tank. The oscillating member is a pipe configuration including a first end portion and a second end portion. The first end portion is supported within the fuel tank and the second end portion connected with the fuel float such that there is a fluidic communication between the hole and the oscillating member. The fuel fumes generated in the inside space of the fuel tank is passed through the hole to the oscillating member and is collected from the first end portion.
[006] In an embodiment, the fuel tank breathing system further includes a fuel stay and a mounting bracket. The fuel stay is pivotally mounted to the first end portion thereon. The mounting bracket is disposed on a lower portion of the fuel tank for supporting the fuel stay. In an embodiment, fuel tank breathing system further includes a canister and a tube. The canister includes an input tube. The tube connects the first end portion of the oscillating member to the input tube of the canister for passing fuel fumes to the canister.
[007] In an embodiment, the fuel tank breathing system further includes a roll-over valve. The roll-over valve is connected between the tube and the input tube. The fuel fumes pass through the roll-over valve to the input tube. In an embodiment the fuel float further includes a projection extending from one end of the fuel float includes the hole. In an embodiment, the second end portion of the oscillating member is coupled to the hole. In an embodiment, the hole is positioned at a point on the fuel float. The point is at a vertically highest point in the fuel float when the two-wheeled vehicle is in an upright position.
[008] In an embodiment, a two-wheeled vehicle is disclosed. The two-wheeled vehicle includes a fuel tank and a fuel tank breathing system. The fuel tank breathing system includes a fuel float and an oscillating member. The fuel float is of a hollow configuration and positioned in the fuel tank of the two-wheeled vehicle for floating over the fuel present in the fuel tank. The fuel float includes a hole exposed to an inside space of the fuel tank. The oscillating member is coupled with the fuel float and is adapted to rotate based on a fuel level of the fuel present in the fuel tank. The oscillating member is a pipe configuration including a first end portion and a second end portion. The first end portion is supported within the fuel tank and the second end portion connected with the fuel float such that there is a fluidic communication between the hole and the oscillating member. The fuel fumes generated in the inside space of the fuel tank is passed through the hole to the oscillating member and is collected from the first end portion.
[009] In an embodiment, the two-wheeled vehicle further includes a fuel stay, an electronic unit and a mounting bracket. The fuel stay is pivotally mounted to the first end portion thereon. The electronic unit is configured for sensing a relative rotary motion of the oscillating member to the fuel stay to indicate the fuel level in the fuel tank based on sensed information of the relative rotary motion. The mounting bracket is disposed on a lower portion of the fuel tank for supporting the fuel stay and the electronic unit.
[0010] In an embodiment, the two-wheeled vehicle further includes a canister, a tube and a roll-over valve. The canister includes an input tube. The tube connects the first end portion of the oscillating member to the input tube of the canister for passing fuel fumes to the canister. The roll-over valve is connected between the tube and the input tube. The fuel fumes pass through the roll-over valve to the input tube.
BRIEF DESCRIPTION OF THE DRAWINGS

[0011] The invention itself, together with further features and attended advantages, will become apparent from consideration of the following detailed description, taken in conjunction with the accompanying drawings. One or more embodiments of the present invention are now described, by way of example only wherein like reference numerals represent like elements and in which:
[0012] Figure 1 illustrates a view of a two-wheeled vehicle having a fuel tank breathing system, according to an embodiment of the present invention;
[0013] Figure 2 illustrates a view of a fuel tank, according to an embodiment of the present invention; and
[0014] Figure 3 illustrates exploded view depicting components of the fuel tank breathing system, according to an embodiment of the present invention.
[0015] The drawings referred to in this description are not to be understood as being drawn to scale except if specifically noted, and such drawings are only exemplary in nature.

DETAILED DESCRIPTION

[0016] While the invention is susceptible to various modifications and alternative forms, an embodiment thereof has been shown by way of example in the drawings and will be described here below. It should be understood, however that it is not intended to limit the invention to the particular forms disclosed, but on the contrary, the invention is to cover all modifications, equivalents, and alternative falling within the spirit and the scope of the invention.
[0017] The terms “comprises”, “comprising”, or any other variations thereof, are intended to cover a non-exclusive inclusion, such that a setup, structure or method that comprises a list of components or steps does not include only those components or steps but may include other components or steps not expressly listed or inherent to such setup or structure or method. In other words, one or more elements in a system or apparatus proceeded by “comprises… a” does not, without more constraints, preclude the existence of other elements or additional elements in the system or apparatus.
[0018] For the better understanding of this invention, reference would now be made to the embodiment illustrated in the accompanying figures and description here below, further, in the following figures, the same reference numerals are used to identify the same components in various views.
[0019] While the present invention is illustrated in the context of a saddle riding type vehicle, however, breathing system and aspects and features thereof can be used with other type of vehicles as well. The terms “vehicle”, “two wheeled vehicle”, “two-wheeled vehicle” and “motorcycle” may have been interchangeably used throughout the description. The term “two wheeled vehicle” includes vehicles such as motorcycles, scooters, bicycles, mopeds, scooter type vehicle, all-terrain vehicles (ATV) and the like.
[0020] The terms “front / forward”, “rear / rearward / back / backward”, “up / upper / upward”, “down / downward / lower / lower ward” that may be used therein represent the directions as seen from a vehicle driver sitting astride and these directions are referred by arrows Fr, Rr, U, Lr in the drawing. Further, “left / leftward”, “right / rightward” that may be used herein represent the directions as seen from a vehicle driver sitting astride.
[0021] Figure 1 illustrates a side view of a two-wheeled vehicle (100) according to an embodiment of the present invention. The two-wheeled vehicle (100) comprises, inter-alia, a front fork (121), a main frame (102), a head pipe (122), a front fender (133), a front wheel (123), a headlight (132), a steering handle bar (124), a fuel tank (125) an engine (126), a swing arm (173), a rear wheel (127), a rear fender (116), a tail light (117) and a seat (130). The frame (102) is intended to support the seat (130) (rider and / or pillion) disposed above the rear wheel (127). The rear wheel (127) is covered from above by the rear fender (116). The tail light (117) is mounted on the rear fender (116). It may be noted that the two-wheeled vehicle (100) is shown to have include above stated parts, however, those skilled in the art would appreciate that the two-wheeled vehicle (100) includes other parts which may not be relevant for explaining the present invention and hence are not shown and described.
[0022] With reference to Figure 1, the engine (126) is provided with a crankcase that houses a crankshaft (not shown). A cylinder block is provided to the front of the crankcase, and a cylinder head is provided to the cylinder block. The engine (126) is located under the main frame (102). The engine (126) is placed below the main frame (102) and is oriented towards steering the handle bar (124). An exhaust pipe extends from the engine (126), and a muffler is connected to the rear end of the exhaust pipe. Air to the engine (126) is supplied by an air cleaner (168). The air cleaner (168) is arranged in a space surrounded by the main frame (102) of the two-wheeled vehicle (100). The air cleaner (168) is connected to a carburettor (not visible in Figure). The fuel tank (125) is connected to the engine (126) through the carburettor. In an embodiment, the carburettor may be a throttle body in case of a fuel injection system.
[0023] Figure 2 illustrates a view of the fuel tank (125). The fuel tank (125) of the two wheeled vehicle (100) includes a fuel lid (152). The fuel lid (152) covers the fuel filling opening provided on an upper part of the fuel tank (125). The fuel from the fuel tank (125) flows to the carburettor. The carburettor gets intake air from the air cleaner (168) and the fuel from the fuel tank (125). The air and fuel are mixed in the carburettor, according to the engine (126) requirements and then are fed to the engine (126).
[0024] The present invention provides a fuel tank breathing system (155) at least partially placed inside the fuel tank (125) which is described below with reference to Figures 2 and 3.
[0025] Figure 3 illustrates an exploded view of the fuel tank breathing system (155). The fuel tank breathing system (155) comprises a fuel float (153), an oscillating member (154) including a first end portion (154a) and a second end portion (154b), a tube (157) and a tank mounting bracket (160). In an embodiment, the fuel tank breathing system (155) also comprises a roll over valve (158), a fuel stay (164), an electronic unit (156), etc.
[0026] As can be seen in the Figure 3, the first end portion (154a) of the oscillating member (154) is pivotally mounted to the fuel stay (164). The oscillating member (154) is a hollow pipe. The oscillating member (154) rotates depending upon the fuel level inside the fuel tank (125). The relative rotary motion of the oscillating member (154) to the fuel stay (164) is sensed by the electronic unit (156); and the electronic unit (156) indicates the fuel level in the fuel tank (125) based on the sensed information of the relative rotary motion.
[0027] The fuel float (153) is attached to the second end portion (154b) i.e. the free end portion of the oscillating member (154). The fuel float (153) facilitates in maintaining the position of the oscillating member (154) above the fuel level. The fuel float (153) is a plastic body which floats on the fuel surface inside the fuel tank (125).
[0028] In an embodiment (e.g., as shown in Figure 2), the fuel float (153) may be a hollow body including a hole (161) at at least one end of the fuel float (153). The hole (161) acts as an opening of the fuel float (153). In an embodiment, the hole (161) is configured at the highest possible point on the fuel float (153), above the fuel surface inside the fuel tank (125). The hole (161) fluidically connects the inside space of the fuel tank (125) and the fuel float (153). The other end of the fuel float (153) opposite to the hole (161) is connected to the second end portion (154b) of the oscillating member (154) so that there is a fluidic communication between the inside space of the fuel tank (125), the fuel float (153) that is hollow and the oscillating member (154) that is a hollow pipe.
[0029] In another embodiment, the hole (161) may be configured in a projection (163) extending from the fuel float (153). For example, the projection (163) extends from one end of the fuel float (153) and include the hole (161) configured such that the hole (161) fluidically connects the inside space of the fuel tank (125) and fuel float (153). Also, the other end of the fuel float (153) opposite to the projection (163) is connected to the second end portion (154b) of the oscillating member (154) for maintaining a fluidic communication between the inside space of the fuel tank (125), the fuel float (153) and the oscillating member (154).
[0030] In another embodiment, the oscillating member (154) passes through the fuel float (153), and the second end portion (154b) of the oscillating member (154) includes the hole (161) such that the hole (161) fluidically connects the inside space of the fuel tank (125) and the oscillating member (154).
[0031] The fuel tank breathing system (155) includes the tube (157) for example a rubber tube. One end of the tube (157) is connected to the first end portion (154a) of the oscillating member (154) and the other end is connected to a canister (159). In an embodiment, the tube (157) is connected to the canister (159) through the roll over valve (158). The assembly of the fuel float (153), the oscillating member (154), the rubber tube (157), the roll over valve (158), the fuel stay (164) and the electronic unit (156) is mounted on the tank mounting bracket (160). The tank mounting bracket (160) is provided at the lower portion of the fuel tank (125).
[0032] In an embodiment, the roll over valve (158) is mounted on the tank mounting bracket (160) from the outside of the fuel tank (125). The roll over valve (158) is connected to the canister (159) through an input tube (162). The function of the roll over valve (158) is to stop the flow of the fuel out from the fuel tank (125) in case the two-wheeled vehicle (100) topples.
[0033] In operation, the fuel fumes generated in the fuel tank (125) enter through the hole (161) into the oscillating member (154), and from the oscillating member (154) the fuel fumes reach to the roll over valve (158) through the rubber tube (157).
[0034] In the exemplary embodiment, the canister (159) is having three connections as the input tube (162), an output tube (not shown) and a drain tube (not shown). The canister (159) communicates with the fuel tank (125) to adsorb the evaporated fuel conducted from the fuel tank (125) through the input tube (162). The adsorbed fuel is supplied to the carburettor through the output tube. In an embodiment, the fuel discharged from the canister (159) enters the engine (126). The drain tube is a discharge point. While breathing, the atmospheric air enters the canister (159) through the drain tube and travels to the fuel tank through the input tube (162), the roll over valve (158), the rubber tube (157) and the oscillating member (154).
[0035] Various embodiments of the present invention advantageously provide fuel breathing systems that are a cost effective technique for breathing evaporated fuel generated within the fuel tank. Since, such embodiments make use of the existing fuel unit to act as a breather unit, the requirement for a separate breathing system and a separate fuel unit is eliminated, thereby saving cost. It should also be appreciated that the embodiments of the present invention can be applied to the existing fuel tank in two-wheeled vehicles.
[0036] While few embodiments of the present invention have been described above, it is to be understood that the invention is not limited to the above embodiments and modifications may be appropriately made thereto within the spirit and scope of the invention.
[0037] While considerable emphasis has been placed herein on the particular features of this invention, it will be appreciated that various modifications can be made, and that many changes can be made in the preferred embodiments without departing from the principles of the invention. These and other modifications in the nature of the invention or the preferred embodiments will be apparent to those skilled in the art from the disclosure herein, whereby it is to be distinctly understood that the foregoing descriptive matter is to be interpreted merely as illustrative of the invention and not as a limitation.

CLAIMS:
We claim:
1. A fuel tank breathing system (155) in a two-wheeled vehicle (100), the fuel tank breathing system (155) comprising:
a fuel float (153) of a hollow configuration positioned in a fuel tank (125) of the two-wheeled vehicle (100) for floating over fuel present in the fuel tank (125), the fuel float (153) comprising a hole (161) exposed to an inside space of fuel tank (125); and
an oscillating member (154) coupled with the fuel float (153) and adapted to rotate based on a fuel level of the fuel present in the fuel tank (125), the oscillating member (154) being a pipe configuration comprising a first end portion (154a) and a second end portion (154b), first end portion (154a) supported within the fuel tank (125) and the second end portion (154b) connected with the fuel float (153) such that there is a fluidic communication between the hole (161) and the oscillating member (154),
wherein fuel fumes generated in the inside space of the fuel tank (125) is passed through the hole (161) to the oscillating member (154) and is collected from the first end portion (154a).
2. The fuel tank breathing system (155) as claimed in claim 1, further comprising:
a fuel stay (164) for pivotally mounting the first end portion (154a) thereon; and
a mounting bracket (160) disposed on a lower portion of the fuel tank (125) for supporting the fuel stay (164).
3. The fuel tank breathing system (155) as claimed in claim 1, further comprising:
a canister (159) comprising an input tube (162); and
a tube (157) connecting the first end portion (154a) of the oscillating member (154) to the input tube (162) of the canister (159) for passing fuel fumes to the canister (159).
4. The fuel tank breathing system (155) as claimed in claim 3, further comprising:
a roll-over valve (158) connected between the tube (157) and the input tube (162), wherein fuel fumes pass through the roll-over valve (158) to the input tube (162).
5. The fuel tank breathing system (155) as claimed in any of claims 1 to 4, wherein the fuel float (153) further comprises a projection (163) extending from one end of the fuel float (153) comprising the hole (161).
6. The fuel tank breathing system (155) as claimed in any of claims 1 to 5, wherein the second end portion (154b) of the oscillating member (154) is coupled to the hole (161).
7. The fuel tank breathing system (155) as claimed in any of claims 1 to 6, wherein the hole (161) is positioned at a point on the fuel float (153), wherein the point is a vertically highest point in the fuel float (153) when the two-wheeled vehicle (100) is in an upright position.
8. A two-wheeled vehicle (100) comprising:
a fuel tank (125); and
a fuel tank breathing system (155) comprising:
a fuel float (153) of a hollow configuration positioned in the fuel tank (125) for floating over fuel present in the fuel tank (125), the fuel float (153) comprising a hole (161) exposed to an inside space of fuel tank (125); and
an oscillating member (154) coupled with the fuel float (153) and adapted to rotate based on a fuel level of the fuel present in the fuel tank (125), the oscillating member (154) being a pipe configuration comprising a first end portion (154a) and a second end portion (154b), first end portion (154a) supported within the fuel tank (125) and the second end portion (154b) connected with the fuel float (153) such that there is a fluidic communication between the hole (161) and the oscillating member (154),
wherein fuel fumes generated in the inside space of the fuel tank (125) is passed through the hole (161) to the oscillating member (154) and is collected from the first end portion (154a).
9. The two-wheeled vehicle (100) as claimed in claim 8, further comprising:
a fuel stay (164) for pivotally mounting the first end portion (154a) thereon;
an electronic unit (156) for sensing a relative rotary motion of the oscillating member (154) to the fuel stay (164) to indicate the fuel level in the fuel tank (125) based on sensed information of the relative rotary motion; and
a mounting bracket (160) disposed on a lower portion of the fuel tank (125) for supporting the fuel stay (164) and the electronic unit (156).
10. The two-wheeled vehicle (100) as claimed in claim 9, further comprising:
a canister (159) comprising an input tube (162);
a tube (157) connecting the first end portion (154a) of the oscillating member (154) to the input tube (162) of the canister (159) for passing fuel fumes to the canister (159); and
a roll-over valve (158) connected between the tube (157) and the input tube (162), wherein the fuel fumes pass through the roll-over valve (158) to the input tube (162).