FUEL FILLER APPARATUS
TITLE OF THE INVENTION
[001] Fuel filler apparatus
FIELD OF INVENTION
[002] The present invention relates to a fuel filler apparatus, more particularly, the
invention relates to a fuel filler apparatus for a two-wheeled vehicle.
BACKGROUND
[003] Generally, in two-wheeled vehicles, fuel is filled into the fuel tank through a fuel
filler apparatus which is generally fixed to the walls of the fuel tank. The fuel filler apparatus includes a fuel filler structure and a fuel tank cap. The fuel tank cap is removably mounted on the fuel filler structure to access the fuel tank. To access the fuel tank, the user needs to unlock the fuel tank cap and remove the fuel tank cap from the fuel filler structure.
[004] The US Patent 4312649 discloses a fuel tank cap which is hingedly attached to the
fuel filler structure and which has inbuilt gas-liquid separator for collecting the evaporated fuel vapour from the fuel stored in the fuel tank.
[005] In few other arrangements where the fuel tank cap is an independent assembly
separate from the fuel filler structure, the fuel tank cap needs to be completely removed from the fuel filler structure in order to access the fuel tank. Further, when the fuel tank cap is locked onto the fuel filler structure, it can have circumferential movement about the vertical axis of the fuel tank cap.
[006] Sometimes, a protrusion is provided on the fuel tank cap in radial direction, and a
substantially complementary provision is provided on the fuel filler structure to avoid circumferential movement of the fuel tank cap. At the time of closing the fuel tank opening through a fuel tank cap, the protrusion is aligned with the provision provided on the fuel filler structure and circumferential motion of the fuel tank cap is attempted to be avoided.
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[007] However, when the fuel tank cap is locked onto the fuel filler structure, due to
manufacturing constraint, circumferential movement of the fuel tank cap about the vertical axis of the fuel tank cap is unavoidable. Also, over a period of time and frequent use, the degree of circumferential movement of the fuel tank cap is likely to be increased.
[008] For better performance of a gas-liquid separator provide in the fuel tank cap, a
breather hole of the fuel filler structure and a discharge opening provided on the gas-liquid separator of the fuel tank cap should be aligned. Circumferential movement of the fuel tank cap increases the probability of misalignment of the discharge opening and the breather hole. Further, in such arrangement, there are chances of leakage of the vapour into the atmosphere, due to the misalignment.
OBJECT OF INVENTION
[009] The object of this invention is to provide for a two-wheeled vehicle for reducing down circumferential movement of the fuel tank cap with respect to fuel filler structure about the vertical axis of the fuel tank cap.
SUMMARY OF THE INVENTION
[0010] The present invention deals with a two-wheeled vehicle including a fuel tank comprising a fuel filler structure. The fuel filler structure further includes an annular flange structure and the annular flange structure in turn includes a breather hole connected to a breather pipe. A fuel tank cap which is removably connected to the fuel filler structure, includes an extension extending radially outward. This extension includes a discharge hole capable of fluidic communication to a gas-liquid separator, wherein the breather hole and the discharge hole are aligned to provide a fluid communication between the gas-liquid separator and the breather pipe. On locking the fuel tank cap onto the fuel filler structure, the dimension of the breather hole and the discharge hole is dissimilar to the extent that a central angle formed by extremities of any of the breather hole with axis of the annular body or the discharge hole with the fuel tank cap is equal or greater than to the permissible misalignment of the fuel tank cap over the fuel filler structure when the fuel tank cap is locked onto the fuel filler structure.
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[0011] In one embodiment of the two-wheeled vehicle, the dimension of the breather hole is more than the discharge hole, wherein dimension of the breather hole is such that the central angle formed by the extremities of the breather hole with axis of the annular body is greater than or equal to permissible misalignment of the fuel tank cap over the annular flange structure when the fuel tank cap is locked onto the fuel filler structure, so that the fluidic communication from the gas-liquid separator to the breather hole is always ensured.
[0012] In another embodiment of the two-wheeled vehicle, the size of the discharge hole is such that the central angle formed by extremities of the discharge hole with the axis of the fuel tank cap is greater than or equal to the permissible misalignment of the fuel tank cap over the annual flange structure when the fuel tank cap is locked onto the fuel filler structure, so that the fluidic communication from the gas-liquid separator to the breather hole is always ensured.
[0013] In yet another embodiment of the two-wheeled vehicle, the fuel tank cap includes a gas-liquid separator and the extension extends radially outward from the gas-liquid separator.
[0014] In another embodiment of the two-wheeled vehicle, the fuel tank cap includes a protrusion and the annular body comprises a slot on an inner wall, such that the protrusion and the slot are aligned while locking the fuel tank cap onto the fuel filler structure.
[0015] In yet another embodiment of the two-wheeled vehicle the annular flange structure includes a raised portion, the breather hole is placed onto the raised portion.
[0016] In another embodiment of the two-wheeled vehicle, the circumferential length of the raised portion is more than maximum permissible misalignment of the fuel tank cap over the fuel filler structure.
[0017] In yet another embodiment of the two-wheeled vehicle, the vehicle includes a seal member, wherein the seal member further includes a seal breather hole. The seal member is mounted onto the annular flange structure, such that the discharge hole and the breather hole are in fluidic communication with each other via the seal breather hole.
[0018] In another ■ embodiment of the two-wheeled vehicle, wherein dimension and profile of one end of seal breather hole is similar to dimension and profile of the breather
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hole, and dimension and profile of other end of the seal breather hole has same dimension
and profile as that of the discharge hole. [0019] In yet another embodiment of the two-wheeled vehicle, the seal member is
mounted onto a raised portion extending along a peripheral wall of the fuel filler structure
or mounted onto a bottom portion of the extension having the discharge hole. [0020] The invention includes all the embodiments of the two-wheeled vehicle
substantially described herein with reference to and is illustrated by the accompanying
drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] 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, with reference to the accompanied drawing wherein like reference numerals represent like elements and in which:
[0022] Figure 1 is a schematic view of fuel tank, according to an embodiment of the present invention;
[0023] Figure 2 is a schematic view of fuel tank cap having separator, according to an embodiment of the present invention;
[0024] Figure 3 is another schematic view of fuel tank cap having a separator, according to an embodiment of the present invention;
[0025] Figure 4 is a schematic view of fuel filler structure, according to an embodiment of the present invention;
[0026] Figure 5 is another schematic view of fuel filler structure, according to an embodiment of the present invention;
[0027] Figure 6 is a view of fuel filler apparatus illustrating the alignment of fuel tank cap and fuel filler structure, according to an embodiment of the present invention;
[0028] Figure 7 is a schematic view of fuel tank cap, according to an embodiment of the present invention;
[0029] Figure 8 is another schematic view of fuel tank cap, according to an embodiment of the present invention;
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[0030] Figure 9 is a schematic view of fuel filler structure, according to yet an
embodiment of the present invention; [0031] Figure 10 is another schematic view of fuel filler structure, according to an
embodiment of the present invention; [0032] Figure 11 is a view of fuel filler apparatus illustrating the alignment of fuel tank
cap and fuel filler structure, according to an embodiment of the present invention; [0033] Figure 12 is a schematic view of fuel tank cap and fuel filler structure having seal
member, according to an embodiment of the present invention; [0034] Figure 13a is a sectional view of the extension and the annular flange structure of
the fuel filler structure illustrating misalignment of discharge hole and breather hole,
according to an embodiment of the present invention; [0035] Figure 13b is a sectional view of the extension and the annular flange structure of
the fuel filler structure describing the misalignment of discharge hole and breather hole,
according to an embodiment of the present invention; [0036] Figure 14 is a sectional view of the extension of the fuel tank cap and the annular
flange structure of the fuel filler structure having a seal member, according to an
embodiment of the present invention; [0037] 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.
DESCRIPTION
[0038] While the invention is susceptible to various modifications and alternative forms, specific embodiment thereof has been shown by way of example in the drawing and will be described 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.
[0039] The terms "comprises", "comprising", or any other variations thereof, are intended to cover a non-exclusive inclusion, such that a setup, device or method that
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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 device 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.
[0040] The terms "front / forward", "rear / rearward", "up / upper / top", "down / lower", "left / leftward", "right / rightward" used therein represents the directions as seen from a vehicle driver sitting astride and these directions are referred by arrows Fr, Rr, U, Lr, L, R in the drawing Figures.
(0041] While the fuel filler apparatus has been described in the context of a saddle type riding vehicle having a fuel tank. However, this is not limited to the saddle type riding vehicle and the fuel filler apparatus and the features thereof may be used in any other vehicle or machine such as a mowing machine and the like having a fuel tank. Further, the misalignment of fuel tank cap is described with respect to the misalignment of the fuel tank cap over the annular flange structure of the fuel filler structure. Therefore, while describing the misalignment of fuel tank cap only, the terms "annular flange structure" and "fuel filler structure" are being used interchangeably. For example, "misalignment of fuel tank cap over the annular flange structure" is same as "misalignment of fuel tank cap over the fuel filler structure."
[0042] Figure 01 is a fuel tank system (200) having a fuel filler apparatus (201) mounted thereto. The fuel filler apparatus (201), generally, comprises a removable fuel tank cap (204) having a gas-liquid separator (211) [not visible in Figure 1], a fuel filler structure (202), a breather pipe (402, 902) connected to the fuel filler structure (202). Other end of the breather pipe (402, 902) is connected to evaporated fuel collecting device located outside or inside the fuel tank (210). The removable fuel tank cap (204) is adapted to be fitted and locked onto the fuel filler structure (202). Further, a drain pipe (208) is connected to the fuel filler structure (202) for draining out excess fuel which may flow into the fuel filler structure (202) during filling of fuel at fuel filling station. Fuel vapour generated inside the fuel tank (210) is collected in an inbuilt gas-liquid separator (216) of the fuel tank cap (204) (please refer to figure 02) and then it is discharged to the evaporated fuel collecting device through the breather pipe (402, 902). The gas-liquid
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separator (216) has one or more in-built galleries/passages for guiding the fuel vapour towards the breather pipe (402, 902). [0043] Figures 02 and 03 are views of the fuel tank cap (204) having a gas-liquid separator (216) integrally built therein. The fuel tank cap (204) comprises a disc shape roof plate (215), a gas-liquid separator (216), an extension (212), one or more latching members such as latching members (214a) and (214b) and a protrusion (218). The gas-liquid separator (216) attached to bottom surface of the roof plate (215); and one or more annular seal member (not shown in the figures) disposed between the roof plate (215) and the gas-liquid separator (216). Further, one or more latching members (214a, 214b) are provided at the bottom portion of the fuel tank cap (204) for locking the fuel tank cap (204) onto the fuel filler structure (202). Furthermore, as shown in Figure 03, the fuel tank cap (204) has a protrusion (218). In an embodiment, the protrusion (218) is formed on the circumferential wall of the gas-liquid separator (216). Fuel vapour generated inside the fuel tank (210) enters into the inbuilt gas-liquid separator (216) through a vent hole (217) provided on the bottom portion of the fuel tank cap (204). [0044] As shown in the Figure 03, the fuel tank cap (204) is provided with an extension (212) extending radially outward from the gas-liquid separator (216) along the circumferential wall of the gas-liquid separator (216). The extension (212) is provided 5 with a discharge hole (219). The discharge hole (219) is in fluidic communication with the gas-liquid separator (216). Fuel vapour comes out of the gas-liquid separator (216) through the discharge hole (219) of the extension (212) after passing through one or more galleries/passage (not visible in any of the figures) provided inside the gas-liquid separator (216). The extension (212) can have any suitable shape as per requirement. For example, shape of the extension (212) may be of a cuboidal shape, a cylindrical shape, cubical shape, spherical and the like shape. [0045] Figure 04 and Figure 05 are views of the fuel filler structure (400), according to an embodiment of the invention. As shown in the Figure 04 and Figure 05, the fuel filler structure (400) comprises an annular flange structure (409) and an annular body (408). The annular body (408) is extending downward from the annular flange structure (409). In an embodiment, the annular flange structure (409) has a substantially flat surface and spread substantially horizontal. Fuel is filled into the fuel tank (210) through the annular
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body (408). There is provided a peripheral wail (410) that surrounds the entire circumference of the annular flange structure (409). In an embodiment, the peripheral wall (410) extends from the annular flange structure (409) substantially in vertical direction. Further, a slot (406) is provided on the inner wall of the annular body (408) at top portion thereof A breather pipe (402) is connected to the breather hole (404) provided on the annular flange structure (409). The shape of the breather hole (404) may be an oval shape, circular shape, rectangular shape and the like shape. In an embodiment, the shape of the breather hole (404) is an oval shape. The breather pipe (402) is connected to the breather hole (404) from bottom of the annular flange structure (409).
[0046] Figure 6 is a view of the fuel filler apparatus (600) illustrating the alignment of the fuel tank cap (204) and the fuel filler structure (400) before the fuel tank cap (204) is locked onto the fuel filler structure (400), according to an embodiment of the invention. Referring now to Figures 03 and 06, fuel tank cap (204) is adapted to be locked onto the fuel filler structure (400) by aligning the protrusion (218) [please refer Figure 03] of the fuel tank cap (204) with the slot (406) provided on the annular body (408) of the fuel filler structure (400). Further, at the same time, the extension (212) having the discharge hole (219) [please refer Figure 3] gets aligned with and sits on the breather hole (404) provided on the annular flange structure (409). Such alignment establishes fluidic communication path between the discharge hole (219) and the breather hole (404). Since, the breather pipe (402) is connected to the breather hole (404) and the discharge hole (219) is in fluidic communication with the gas-liquid separator (216), the gas-liquid separator (216) comes in fluidic communication with the breather pipe (402).
[0047] When the fuel tank cap (204) is locked onto the fuel filler structure (400), the protrusion (218) fits into the slot (406) thereby prevents the circumferential movement of the fuel tank cap (204) over the fuel filler structure (400) beyond a permissible limit / permissible misalignment. In an embodiment, the dimension of the breather hole (404) is more than the discharge hole (219), the size of the breather hole (404) is such that the central angle formed by the extremities of the breather hole (404) with the axis of the annular body (408) is greater than, or equal to the maximum permissible misalignment of the fuel tank cap (204) over the fuel filler structure (400) whenlhe fuel tank cap (204) is locked onto the fuel filler structure (400). Thus when the fuel tank cap (204) is locked
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onto the fuel filler structure (400), the circumferential displacement of the discharge hole (219) is less or equal to the maximum permissible misalignment of the fuel tank cap (204) over the fuel filler structure (400). That is to say, when the fuel tank cap (204) is locked onto the fuel filler structure (400) and if the fuel tank cap (204) is misaligned then even at least a portion of the discharge hole (219) overlaps with at least a portion of the breather hole (404) thereby continuously establishing fluidic communication path between the discharge hole (219) and the breather pipe (402) connected to the breather hole (404).
[0048] Figure 13a is a sectional view of the extension (212) and the fuel filler structure (409) describing one example of misalignment of the discharge hole (219) and the breather hole (404), according to an embodiment of the present invention. The dimension of breather hole (404) is bigger than the discharge hole (219). Even if the fuel tank cap (204) gets misaligned with the fuel filler structure (400), the discharge hole (219) and the breather hole (404) remains in fluidic communication with each other. Thus, the vapour discharged from the gas-liquid separator (216) through the discharge hole (219) enters into the breather pipe (402) through the breather hole (404) without leaking into the fuel filler structure (409).
[0049] In ah embodiment, the dimension of the breather hole (404) is less than the discharge hole (219). The size of the discharge hole (219) is such that the central angle formed by the extremities of the discharge hole (219) with the axis of the fuel tank cap (204) is greater than, or equal to the permissible misalignment of the fuel tank cap (204) with the fuel filler structure (400) when the fuel tank cap (204) is locked onto the fuel filler structure (400). Thus, when the fuel tank cap (204) is locked onto the fuel filler structure (400), the circumferential displacement of the discharge hole (219) is less or equal to the maximum permissible misalignment of the fuel tank cap (204) over the fuel filler structure (400). Therefore, when the fuel tank cap (204) is locked onto the fuel filler structure (400) and if the fuel tank cap (204) is misaligned then even at least a portion of the discharge hole (219) overlaps with at least a portion of the breather ho|e (404) thereby continuously establishing fluidic communication path between the discharge hole (219) and the breather pipe (402).
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[0050] Figure 13b is a sectional view of the extension (212) and the annular flange structure (409) describing the misalignment of the discharge hole (219) and the breather hole (404), according to an embodiment of the present invention. The dimension of breather hole (404) is less than the discharge hole (219). Even if the fuel tank cap (204) gets misaligned with the annular flange structure (409), the discharge hole (219) and the breather hole (404) remains in fluidic communication with each other. Thus, the vapour discharged from the gas-liquid separator (216) through the discharge hole (219) enters into the breather pipe (402) through the breather hole (404) without leaking into the fuel filler structure (409).
[0051] In an embodiment, as shown in Figure 14, a seal member (913) having a seal breather hole (905) entirely therethrough is provided between the discharge hole (219) and breather hole (404) such that the discharge hole (219) and the breather hole (404) are in fluidic communication with each other. In an embodiment, the seal member (913) is mounted on the bottom surface of the extension (212) having the discharge hole (219). In an embodiment, the seal member (913) is mounted on the portion of the annular flange structure (409) having the breather hole (404). When the fuel tank cap (204) is locked onto the fuel filler structure (400), the protrusion (218) fits into the slot (406) thereby prevents the circumferential movement of the fuel tank cap (204) over the fuel filler structure (400) beyond a permissible limit. , [0052] Figures 07 and 08 are views of the fuel tank cap (700), according to an embodiment of the invention. As shown in Figures 07 and 08, the fuel tank cap (700) is same as the fuel tank cap (204) as described in the earlier embodiment, except that the extension (712) is not fully extended along the peripheral wall of the gas-liquid separator (716). In this embodiment, the fuel tank cap (700) is provided with an extension (712) extending radially outward. The passage / gallery of the gas-liquid separator (716) opens into the extension (712). The extension (712) is in the form of a hollow body in communication with the gallery/passage passage/gallery and the discharge hole (719) is formed at the bottom surface of this hollow body extension (712).
[0053] Figures 09 and 10 illustrate schematic views of the fuel filler structure (900), according to an embodiment of the invention. The fuel filler structure (900) comprises an annular flange structure (909). The annular body (908) extending downward from the
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annular flange structure (909). In an embodiment, the annular flange structure (909) spreads substantially horizontal. Fuel is filled into the fuel tank (210) through the annular body (908). There is provided a peripheral wall (910) that surrounds the entire circumference of the annular flange structure (909). In an embodiment, the peripheral wall (910) extends from the annular flange structure (909) substantially in vertical direction. Further, a slot (906) is provided on the inner wall of the annular body (908) at top portion thereof [0054] Further, annular flange structure (909) has a raised portion (912). The raised portion (912) extends along the peripheral wall (910) of the fuel filler structure (900). The height of the raised portion (912) is such that it touches the extension (712) of the fuel tank cap (700) when the fuel tank cap (700) is locked onto the fuel filler structure (900). A breather pipe (902) is connected to the breather hole (904) provided on the raised portion (912) of the annular flange structure (909). The breather pipe (902) is connected to the breather hole (904) from bottom of the portion (912) of annular flange structure (909).
:'>""*. . [0055] Figure 11 is a view of the fuel filler apparatus (901) illustrating the alignment of
the fuel tank cap (700) and the fuel filler structure (900) before the fuel tank cap (700) is
■■i' locked onto the fuel filler structure (900), according to yet another embodiment of the
'. invention. Referring now to Figures 08 and II, fuel tank cap (700) is adapted to be
> ; locked onto the fuel filler structure (900) by aligning the protrusion (718) of the fuel tank
cap (700) with the slot (906) provided on the annular body (908) of the fuel filler structure (900). Further, at the same time, the extension (712) having the discharge hole (719) gets aligned with and sits on the breather hole (904) provided on the raised portion (912) annular flange structure (909). Such alignment establishes fluidic communication between the discharge hole (719) and the breather hole (904). Since, the breather pipe (902) is connected to the breather hole (904) and the discharge hole (719) is in fluidic communication with the gas-liquid separator (716), the gas-liquid separator (716) comes in fluidic communication with the breather pipe (902). When the fuel tank cap (700) is locked onto the fuel filler structure (900), the protrusion (718) fits into the slot (906) thereby prevents the circumferential movement of the fuel tank cap (700) over the fuel filler structure (900) beyond a permissible limit/permissible misalignment. Further, the
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circumferential length of the raised portion (912) of the annular flange structure (909) is
more than the maximum permissible misalignment of the fuel tank cap (700) over the
fuel filler structure (900).
[0056] In an embodiment, the dimension of the breather hole (904) is more than the
discharge hole (719). The size of the breather hole (904) is such that the central angle
formed by the extremities of the breather hole (904) with the axis of the annular body
(908) is greater than, or equal to the permissible misalignment of the fuel tank cap (700)
over the fuel filler structure (900). Thus, when the fuel tank cap (700) is locked into the
fuel filler structure (900), the circumferential displacement of the discharge hole (719) is
less or equal to the maximum permissible misalignment of the fuel tank cap (700) over
the fuel filler structure (900). That is to say, when the fuel tank cap (700) is locked onto
the fuel filler structure (900) and if the fuel tank cap (700) is misaligned then even at least
a portion of the discharge hole (719) overlaps with at least a portion of the breather hole
= (904) thereby continuously establishing a fluidic communication between the discharge
" hole (719) and the breather pipe (902) connected to the breather hole (904).
■'^ [0057] In an embodiment, the dimension of the breather hole (904) is less than the
•^ discharge hole (719). The size of the discharge hole (719) is such that the central angle
^ formed by the extremities of the discharge hole (719) with the axis of the fuel tank cap
^ (700) is greater than, or equal to the permissible misalignment of the fuel tank cap (700)
'over the annular flange structure (909) when the fuel tank cap (204) is locked onto the
fuel filler structure (900). Thus, when the fuel tank cap (700) is locked onto the fuel filler
structure (900), the circumferential displacement of the discharge hole (719) is less or
equal to the maximum permissible misalignment of the fuel tank cap (700) over the
annular flange structure (909). Therefore, when the fuel tank cap (700) is locked onto the
fuel filler structure (900) and if the fuel tank cap (700) is misaligned then even at least a
portion of the discharge hole (719) overlaps with at least a portion of the breather hole
(904) thereby continuously establishing fluidic communication path between the
discharge hole (719) and the breather pipe (902).
[0058] In an embodiment, as shown in Figure 12, a seal member (913) having a seal
breather hole (905) is provided between the discharge hole (719) and breather hole (904)
such that the discharge hole (719) and the breather hole (904) are in fluidic
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communication with each other. In an embodiment, the seal member (913) is mounted on the raised portion (912) of the annular flange structure (909) of the fuel filler structure (900). In an embodiment, the seal member (913) is mounted to the bottom portion of the extension (712) having the discharge hole (719). As shown in Figure 14, the seal member (913) having seal breather hole (905) in one end having same dimension and profile as that of the breather hole (904). Further, the other end of the seal breather hole (905) has same dimension and profile as that of the discharge hole (719). In an embodiment, the seal member (913) is mounted on the portion (912) annular flange structure (909) such that it aligns with the breather hole (904) thereby fluidly connected to the breather hole (904). [0059] While considerable emphasis has been placed herein on the particular features of this invention, it will be, appreciated that various modificafions can be made, and that many changes can be made in the preferred embodiments without departing from the principles of the invention. For example, various types of flat seal member having different shapes and profiles may be used in the fuel filler structure. Further, the embodiments are disclosed with respect to the annular fuel filler structure. However, it should be noted that the present invention may be implemented in a rectangular fuef filler structure. 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.

We claim:
1. A two-wheeled vehicle comprising:
- a fuel tank comprising a fuel filler structure, the fuel filler structure further comprises an annular flange structure and the annular flange structure comprises a breather hole connected to a breather pipe;
- a fuel tank cap adapted to be removably connected to the fuel filler structure, the fuel tank cap comprising an extension extending radially outward, wherein the extension comprises a discharge hole fluidic communication to a gas-liquid separator;
wherein the breather hole and the discharge hole are aligned to provide a fluid communication between the gas-liquid separator and the breather pipe, on locking the fuel tank cap onto the fuel filler structure, and
wherein dimension of the breather hole and the discharge hole is dissimilar to the extent that a central angle formed by extremities of any of the breather hole with axis of the annular body or the discharge hole with the fuel tank cap is equal or greater than to the permissible misalignment of the fuel tank cap over the fuel filler structure when the fuel tank cap is locked onto the fuel filler structure.
2. The two-wheeled vehicle according to claim 1, wherein dimension of the breather hole is more than the discharge hole, wherein dimension of the breather hole is such that the central angle formed by the extremities of the breather hole with axis of the annular body is greater than or equal to permissible misalignment of the fuel tank cap over the annular flange structure when the fuel tank cap is locked onto the fuel filler structure, so that the fluidic communication from the gas-liquid separator to the breather hole is always ensured.
3. The two-wheeled vehicle according to claim 1, wherein dimension of the breather hole is less than the discharge hole, wherein size of the discharge hole is such that the central angle formed by extremities of the discharge hole with the axis of the fuel tank cap is greater than or equal to the permissible misalignment of the fuel tank cap over the annual flange structure when the fuel tank cap is locked onto the fuel filler structure, so that the fluidic communication from the gas-liquid separator to the breather hole is always ensured.
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4. The two-wheeled vehicle according to claim I, wherein the fuel tank cap comprises a gas-liquid separator and the extension extends radially outward from the gas-liquid separator.
5. The two-wheeled vehicle according to claim 1, wherein the fuel tank cap comprises a protrusion and the annular body comprises a slot on an inner wall, such that the protrusion and the slot are aligned while locking the fuel tank cap onto the fuel filler structure.
6. The two-wheeled vehicle according to the claim 1, wherein the annular flange structure comprises a raised portion, the breather hole is placed onto the raised portion.
7. The two-wheeled vehicle according to the claim 6, wherein circumferential length of the raised portion is more than maximum permissible misalignment of the fuel tank cap over the fuel filler structure.
8. The two-wheeled vehicle according to the claim 1 comprising:
- a seal member, wherein the seal member further comprising a seal breather hole, wherein the seal member is mounted onto the annular flange structure, such that the discharge hole and the breather hole are in fluidic communication with each other via the seal breather hole.
9. The two-wheeled vehicle according to the claim 8, wherein dimension and profile of one end
of seal breather hole is similar to dimension and profile of the breather hole, and dimension and
profile of other end of the seal breather hole has same dimension and profile as that of the
discharge hole.
10. The two-wheeled vehicle according to claims 8, wherein the seal member is mounted onto a
raised portion extending along a peripheral wall of the fuel filler structure or mounted onto a
bottom portion of the extension having the discharge hole.
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11. The two-wheeled vehicle as substantially described herein with reference to and as illustrated by the accompanying drawings.