Description:

FORM 2
THE PATENTS ACT, 1970
(39 of 1970)
&
THE PATENTS RULES, 2003
COMPLETE SPECIFICATION
[See section 10, Rule 13]

FUEL TANK SYSTEM OF VEHICLE

HERO MOTOCORP LIMITED, an Indian Company at: The Grand Plaza, Plot No.2, Nelson Mandela Road, Vasant Kunj- Phase -II, New Delhi, India, 110 070

THE FOLLOWING SPECIFICATION PARTICULARLY DESCRIBES THE INVENTION AND THE MANNER IN WHICH IT IS TO BE PERFORMED.

FIELD OF THE INVENTION:
[001] The present invention relates to a fuel tank system of a vehicle, and more particularly to a fuel retaining structure of the fuel tank system.

BACKGROUND OF THE INVENTION:
[002] With the augmentation of technology in the automotive industry, there has been an enormous development of technology in multiple verticals of the product line-ups and technology front for any vehicle. The vehicle, particularly vehicle configured to be ridden such as motorized scooter, motorcycle, three-wheeled vehicle, and four-wheeled vehicle such as all-terrain vehicle (ATV), comprise a fuel tank system to store and provide necessary fuel required by an engine to power the vehicle. The fuel tank system comprises a fuel tank and a fuel pump module. The fuel tank is used to store the fuel required to power the vehicle. The fuel pump module pumps necessary fuel from the fuel tank to the engine to generate required power to operate the vehicle, through fuel lines or hoses.

[003] More specifically, the fuel tank system of a vehicle is one of most the vital components of the vehicle. Numerous developments have happened over the years to make the fuel tank system more reliable, efficient and economic. However, the fuel tank systems were not adapted for various real life situation where performance was observed to be under par the demands and requirements.

[004] Conventionally, the fuel pump module is mounted on the bottom wall of the fuel tank. In one example, the fuel pump module is mounted on one side of the top surface of the bottom wall. However, in the side mounting condition of the fuel pump module, during braking or downhill conditions, the fuel stored within the fuel tank moves towards front portion of the fuel tank, during this condition the fuel pump module may not have enough fuel available to pump towards the engine of the vehicle, this causes dry run of the fuel pump module, which may damage the fuel pump module, the engine etc., which is undesirable.

[005] Likewise, during accelerating or uphill conditions, the fuel stored within the fuel tank moves towards the rear portion of the fuel tank, during this condition the fuel pump module may not have enough fuel available to pump towards the engine of the vehicle, this causes dry run of the fuel pump module, which may damage the fuel pump module, the engine etc., which is undesirable.

SUMMARY OF THE INVENTION:
[006] This Summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key or essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter.

[007] Accordingly, the present invention provides a fuel tank system of a vehicle, comprising a fuel tank comprising a bottom wall for storing the fuel; a fuel pump module accommodated in the fuel tank, the fuel pump module comprising a fuel entry inlet; and a partition wall extending a width direction of the vehicle from the bottom wall of the fuel tank.

[008] In an embodiment of the invention, the partition wall is positioned behind the fuel entry port of the fuel pump module in a vehicle length direction and a distance between the partition wall and the fuel entry port as measured along the vehicle length direction is in the range of 0.1 mm to 10 mm.

[009] In another embodiment of the invention, the partition wall is positioned ahead of the fuel entry port of the fuel pump module in a vehicle length direction and a distance between the partition wall and the fuel entry port as measured along the vehicle length direction is in the range of 0.1 mm to 5 mm.

[0010] In yet another embodiment of the invention, the fuel tank comprises a bulging portion protruding from the bottom wall and dividing the fuel tank into a first portion and a second portion, the first portion comprising a first path allowing flow of fuel in a length direction of the vehicle, the second portion comprising a second path allowing flow of fuel in a length direction of the vehicle; the fuel pump module and the partition wall are co-located in any one of the first path and the second path.

[0011] In still another embodiment of the invention, the partition wall upon being located in the first path or the second path increases resistance of the fuel to flow in the length direction relative to the first path or the second path not having the partition wall located therein.

[0012] In a further embodiment of the invention, the fuel tank comprises a first side wall protruding from the bottom wall; a second side wall protruding from the bottom wall; a fuel filling unit; and a cap.

[0013] In a furthermore embodiment of the invention, the partition wall comprises a bottom edge, a first vertical edge extending in an upward direction from the bottom edge, a second vertical edge extending in an upward direction from the bottom edge and being spaced apart from the first vertical edge; and a top edge joining the first vertical edge and the second vertical edge.

[0014] In another embodiment of the invention, the first vertical edge being spaced apart from the first side wall such that a distance between the first vertical edge and the first side wall is in the range of 0.01 to 5mm.

[0015] In yet another embodiment of the invention, the partition wall comprises an aperture between the first vertical edge and the second vertical edge, such that the aperture is proximate to the top edge or terminates at the top edge and wherein a dimension of the aperture is less than a distance between the first vertical edge and the second vertical edge.

[0016] In a further embodiment of the invention, the aperture is substantially aligned with the fuel entry inlet in a vehicle length direction.

[0017] In a furthermore embodiment of the invention, the fuel pump module comprises a horizontal fuel pump module comprising a fuel pump and a fuel filter.

[0018] An advantage of the invention is that fuel is continuously supplied to the fuel pump module during braking or downhill conditions i.e. when the fuel stored within the fuel tank moves towards front portion of the fuel tank. Another advantage of the invention is that fuel is continuously supplied to the fuel pump module during accelerating or uphill conditions i.e. when the fuel stored within the fuel tank moves towards rear portion of the fuel tank. Thus, the probability of dry run of the fuel pump module, damage to the fuel pump module, and damage to the engine is substantially reduced. The fuel is retained at the inlet of the pump and continuously supplied to the fuel pump module even under a variety of conditions including braking condition, downhill condition, vehicle inclined condition, and vehicle accelerating condition.

[0019] Another advantage of the invention is that the partition wall can be located easily within the fuel tank. Yet another advantage of the invention is that the partition wall can be erected within the fuel tank in a cost effective manner. Yet another advantage of the invention is that aspects such as shape of the partition wall, size of the partition wall, location of the partition wall within the fuel tank can be modified depending upon a variation in shape of the fuel tank, size of the fuel tank, etc.

[0020] To further clarify the advantages and features of the invention, a more particular description of the invention will be rendered by reference to specific embodiments thereof, which is illustrated in the appended drawings. It is appreciated that these drawings depict only typical embodiments of the invention and are therefore not to be considered limiting of its scope. The invention will be described and explained with additional specificity and detail with the accompanying drawings.

BRIEF DESCRIPTION OF THE FIGURES:
[0021] In order that the invention may be readily understood and put into practical effect, reference will now be made to exemplary embodiments as illustrated with reference to the accompanying drawings, where like reference numerals refer to identical or functionally similar elements throughout the separate views. The figures together with a detailed description below, are incorporated in and form part of the specification, and serve to further illustrate the embodiments and explain various principles and advantages, in accordance with the present invention where:

[0022] Figure 1 illustrates a side view of the vehicle in accordance with an embodiment of the invention;

[0023] Figure 2 illustrates a partial cross sectional view of fuel tank system in accordance with an embodiment of the invention;

[0024] Figure 3 illustrates a bulging portion of the fuel tank of the vehicle in accordance with an embodiment of the invention;

[0025] Figure 4 illustrates location of the partition wall (120) within the fuel tank in accordance with an embodiment of the invention;

[0026] Figure 5 illustrates location of the partition wall (120) within the fuel tank in accordance with an alternative embodiment of the invention;

[0027] Figure 6 illustrates construction of the partition wall located within the fuel tank in accordance with an embodiment of the invention;

[0028] Figure 7 illustrates a side cross sectional view of fuel tank showing movement of the fuel during braking or downhill conditions i.e. showing movement of the fuel tank towards front portion of the fuel tank; and

[0029] Figure 8 illustrates a side cross sectional view of fuel tank showing movement of the fuel during accelerating or uphill conditions i.e. showing movement of the fuel tank towards rear portion of the fuel tank.

[0030] It may be noted that to the extent possible, like reference numerals have been used to represent like elements in the drawings. Further, skilled artisans will appreciate that elements in the drawings are illustrated for simplicity and may not have been necessarily been drawn to scale. For example, the dimensions of some of the elements in the drawings may be exaggerated relative to other elements to help to improve understanding of aspects of the present invention. Furthermore, one or more elements may have been represented in the drawings by conventional symbols, and the drawings may show only those specific details that are pertinent to understanding the embodiments of the present invention so as not to obscure the drawings with details that will be readily apparent to those of ordinary skill in the art having the benefit of the description herein.

Detailed Description of the Invention:
[0031] For the purpose of promoting an understanding of the principles of the invention, reference will now be made to the embodiment illustrated in the drawings and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended, such alterations and further modifications in the illustrated device, and such further applications of the principles of the invention as illustrated therein being contemplated as would normally occur to one skilled in the art to which the invention relates.

[0032] It will be understood by those skilled in the art that the foregoing general description and the following detailed description are explanatory of the invention and are not intended to be restrictive thereof.

[0033] As used in the description herein and throughout the claims that follow, the meaning of “a,” “an,” and “the” includes plural reference unless the context clearly dictates otherwise. Also, as used in the description herein, the meaning of “in” includes “in” and “on” unless the context clearly dictates otherwise.

[0034] Reference throughout this specification to “an aspect”, “another aspect” or similar language means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, appearances of the phrase “in an embodiment”, “in another embodiment”, and similar language throughout this specification may, but do not necessarily, all refer to the same embodiment.

[0035] The terms "comprises", "comprising", or any other variations thereof, are intended to cover a non-exclusive inclusion, such that one or more devices or sub-systems or elements or structures or components proceeded by "comprises... a" does not, without more constraints, preclude the existence of other devices or other sub-systems or other elements or other structures or other components or additional devices or additional sub-systems or additional elements or additional structures or additional components.

[0036] As used herein, and unless the context dictates otherwise, the terms "coupled to", “connected to”, “operably connected to”, and “operatively connected to” are intended to include both direct connection / coupling (in which two elements that are coupled / connected to each other contact each other) and indirect coupling / connection (in which at least one additional element is located between the two elements). Therefore, the terms "coupled to" and "coupled with" are used synonymously. Similarly, the terms “connected to” and “connected with” are used synonymously.

[0037] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one ordinary skilled in the art to which this invention belongs. The device, methods, and examples provided herein are illustrative only and not intended to be limiting.

[0038] The use of any and all examples, or exemplary language (e.g. “such as”) provided with respect to certain embodiments herein is intended merely to better illuminate the invention and does not pose a limitation on the scope of the invention otherwise claimed. No language in the specification should be construed as indicating any non-claimed element as being essential to the practice of the invention.

[0039] Groupings of alternative elements or embodiments of the invention disclosed herein are not to be construed as limitations. Each group member can be referred to and claimed individually or in any combination with other members of the group or other elements found herein. One or more members of a group can be included in, or deleted from, a group for reasons of convenience and/or patentability. When any such inclusion or deletion occurs, the specification is herein deemed to contain the group as modified thus fulfilling the written description of all Markush groups used in the appended claims.

[0040] Embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

[0041] The terms “front / forward”, “rear / rearward / back / backward”, “up / upper / top”, “down / lower / lower ward / downward, bottom”, “left / leftward”, “right / rightward” used therein represents the directions as seen from a vehicle driver sitting astride.

[0042] While the present invention is illustrated in the context of a vehicle, however, cover and aspects and features thereof can be used with other types of vehicles as well. The terms “vehicle”, “two wheeled vehicle” and “motorcycle” have been interchangeably used throughout the description. The term “vehicle” comprises vehicles such as motorcycles, scooters, bicycles, mopeds, scooter type vehicles, All-Terrain Vehicles (ATV) and the like.

[0043] Referring to Figure 1 there is illustrated a vehicle (10). The vehicle (10) comprises, inter-alia, a front fork (12), a head pipe (14), a front fender (16), a front ground engaging member (18), a rear ground engaging member (20), a headlight (22), a steering handle bar (24), a power unit (28), a rear fender (30), a tail light (32), a seat (34), an exhaust pipe (36), a rear cushion (38), a body frame (40), and a fuel tank system (100) having a fuel tank (102). The head pipe rotatably supports the steering handle bar (24) and the steering handle bar (24) is configured to be rotated by the rider to steer the vehicle (10). The front ground engaging member (18) is operatively connected to the steering handle bar (24) via the front fork (12). The front ground engaging member (18) is in front portion of the vehicle (10) and is at least partially covered by the front fender (16) while the rear ground engaging member (20) is in rear portion of the vehicle (10) and is at least partly covered by the rear fender (30). The headlight (22) is disposed above the front ground engaging member (18) while the tail light (32) is disposed above the rear ground engaging member (20). In an embodiment of the invention, the fuel tank system (100) is disposed between the steering handle bar (24) and the seat (34). The seat (34) provides seating for a rider and a passenger of the vehicle (10). In an embodiment of the invention, the power unit (28) is disposed below the fuel tank system (100) and the exhaust pipe (36) is connected to the power unit (28). The exhaust pipe (36) processes the exhaust air as produced by the power unit (28) before dispensing it to the environment. The rear ground engaging member (20) is rotatably supported by the body frame (40) and is coupled to the body frame (40) via the rear cushion (38). The body frame (40) also supports the power unit (28), the seat (34) and the fuel tank system (100). It may be noted that the vehicle (10) may include other parts which may not be relevant for explaining the present invention and hence not shown and described.

[0044] Now referring to Figure 2, there is illustrated a cross sectional view of fuel tank system (100) in accordance with an embodiment of the invention. The fuel tank system (100) comprises a fuel tank (102) adapted to store the fuel. The fuel tank (102) comprises a bottom wall (104); a first side wall (106), a second side wall (108) and a top wall (110). The first side wall (106) and the second side wall (108) protrude from the bottom wall (104) and the top wall (110) interconnects the first side wall (106) and the second side wall (108).

[0045] In an embodiment of the invention, the fuel tank (102) further comprises a fuel filling unit (112) that is disposed on the top wall (110) and a cap (not shown) for selectively closing the fuel filling unit (112). The fuel tank (102) further comprises a fuel pump module (116). The fuel pump module (116) further comprises a fuel entry inlet (118). The fuel filling unit (112) is configured to receive a spout (not shown) of a fuel supply system (not shown), during fuel filling condition. The fuel to be stored within the fuel tank (102) enters through the fuel filling unit (112). The cap (148) covers the fuel filling unit (112). In an embodiment of the invention, the fuel tank (102) stores and supplies necessary fuel to a fuel pump module (112). The fuel pump module (112) supplies the fuel to the power unit (28) to generate power within the vehicle (10). In an embodiment of the invention, the fuel tank (102) comprises a partition wall (120) that is extended in a width direction of the vehicle (10) from the bottom wall (104) of the fuel tank (102).

[0046] Figure 3 illustrates a bulging portion of the fuel tank of the vehicle in accordance with an embodiment of the invention. The bulging portion (122) protrudes from the bottom wall (104) and divides the fuel tank (102) into two portions i.e. a first portion (124) and a second portion (126). The first portion (124) comprises a first path (128) and the second portion (126) comprising a second path (130). In an embodiment of the invention, the fuel pump module (116) and the partition wall (120) are located in the first path (128). The partition wall (120) upon being located in the first path (128) increases resistance of the fuel to flow in the length direction relative to the first path (128) not having the partition wall (120) located therein.

[0047] In an alternative embodiment of the invention (not shown), the fuel pump module (116) and the partition wall (120) are located in the second path (130). The partition wall (120) upon being located in the second path (130) increases resistance of the fuel to flow in the length direction relative to the second path (130) not having the partition wall (120) located therein.

[0048] Figure 4 illustrates location of the partition wall (120) within the fuel tank in accordance with an embodiment of the invention. In particular, the partition wall (120) is positioned behind the fuel entry inlet (118) of the fuel pump module (116) in a vehicle length direction. In a embodiment of the invention, a distance between the partition wall (120) and the fuel entry inlet (118) as measured along the vehicle length direction (L1) is in the range of 0.1 mm to 10 mm.

[0049] Figure 5 illustrates location of the partition wall (120) within the fuel tank in accordance with an alternative embodiment of the invention. In particular, the partition wall (120) is positioned ahead of the fuel entry inlet (118) of the fuel pump module (116) in a vehicle length direction. In an embodiment of the invention a distance between the partition wall (120) and the fuel entry inlet (118) as measured along the vehicle length direction (L2) is in the range of 0.1 mm to 5 mm.

[0050] Figure 6 illustrates a close-up view of the partition wall which is positioned within the fuel tank in accordance with an embodiment of the invention. The partition wall (120) comprises a bottom edge (132), a first vertical edge (134), a second vertical edge (136) and a top edge (138). The first vertical edge (134) extending in an upward direction from the bottom edge (132). The first vertical edge (134) being spaced apart from the first side wall (106) such that a distance between the first vertical edge (134) and the first side wall (106) is in the range of 0.01 to 5mm.

[0051] In an embodiment of the invention, the second vertical edge (136) extending in an upward direction from the bottom edge (132). The second vertical edge (136) is being spaced apart from the first vertical edge (134). The second vertical edge (136) is being spaced apart from the first vertical edge (134). The top edge (138) joining the second vertical edge (134) and the first vertical edge (136).

[0052] In an embodiment of the invention, the partition wall (120) comprises an aperture (140) between the first vertical edge (134) and the second vertical edge (136), such that the aperture (140) is proximate to the top edge (138) or terminates at the top edge (138). A dimension of the aperture (140) is less than a distance between the first vertical edge (134) and the second vertical edge (136). Taking into consideration Figure 6 and Figure 2 together, the aperture (140) is substantially aligned with the fuel entry inlet (118) in a vehicle length direction.

[0053] Figure 7 illustrates a side cross sectional view of fuel tank in a brake is applied condition of the vehicle or in a down-hill condition of the vehicle in accordance with an embodiment of the invention. In an embodiment of the invention, when the brakes are applied on a vehicle or when the vehicle is on a down-hill condition, the fuel flows from rear end to front end direction of the vehicle. However, during this flow of the fuel from rear end to front end direction of the vehicle, a part of the fuel comes in contact with the partition wall (120), due to which a first wave pattern (146) is formed within the fuel tank (102). Due to formation of the first wave pattern (146), a part of the fuel enters into the fuel pump module (116) through aperture formed in the partition wall (120). Thus, the partition wall (120) prevents excessive movement of the fuel towards the front part of the fuel tank, during braking or cornering maneuvers or in a down-hill condition. The first wave pattern (146) comprises a first intermediate peak fuel portion (148) in close proximity of the fuel entry inlet (118). The first intermediate peak fuel portion (148) helps in maintaining a steady supply of fuel to the fuel pump module (116), regardless of the braking force applied or the down-hill condition. Thus, the partition wall (120) helps prevent fuel starvation, particularly during hard braking maneuvers or down-hill vehicle movement condition.

[0054] Figure 8 illustrates a side cross sectional view of fuel tank in an accelerator applied condition of the vehicle or in an up-hill condition of the vehicle in accordance with an embodiment of the invention. In an embodiment of the invention, in an accelerator applied condition of the vehicle or when the vehicle is an up-hill condition, the fuel flows from front end to rear end direction of the vehicle. However, during this flow of the fuel from front end to rear end direction of the vehicle, a part of the fuel comes in contact with the partition wall (120), due to which a second wave pattern (150) is formed within the fuel tank (102). Due to formation of the second wave pattern (150), a part of the fuel enters into the fuel pump module (116) through aperture formed in the partition wall (120). Thus, the partition wall (120) prevents excessive movement of the fuel towards the rear part of the fuel tank, during accelerator applied condition of the vehicle or when the vehicle is an up-hill condition. The first wave pattern (150) comprises a second intermediate peak fuel portion (152) in close proximity of the fuel entry inlet (118). The second intermediate peak fuel portion (152) helps in maintaining a steady supply of fuel to the fuel pump module (116), regardless of the accelerator applied condition of the vehicle or the up-hill condition. Thus, the partition wall (120) helps prevent fuel starvation, particularly during accelerator applied condition of the vehicle or when the vehicle is an up-hill condition.

[0055] Thus, an advantage of the invention is that the partition wall ensures steady supply of fuel to the fuel pump module (116) regardless of (a) brake applied condition; (b) the vehicle being on a down-hill condition; (c) accelerator applied condition; (d) the vehicle being on a down-hill condition; and (e) any other side maneuvering condition of the vehicle. Thus, the fuel pump module (116) does not face fuel starvation or dry run. By avoiding “dry run”, a life span of the fuel pump module (116) is increased. Additionally, by avoiding “dry run”, continued supply of fuel to the power unit (28) is ensured.

[0056] In an embodiment of the invention, the partition wall (120) can be located easily within the fuel tank (102). For example, partition wall (120) may be formed as a separate entity and can be attached to the bottom wall (104) of the fuel tank (102). The partition wall (120) can be attached to the bottom wall (104) of the fuel tank (102) by any of the conventional techniques. Alternatively, the partition wall (120) may be formed as an integral part of the bottom wall (104), for example in the same manner in which the bulging portion (122) is formed on the bottom wall (104). Thus, another advantage of the invention is that the partition wall (120) can be provided within the fuel tank (102) in a cost effective manner.

[0057] Yet another advantage of the invention is that of the invention is that aspects such as shape of the partition wall (120), size of the partition wall (120), location of the partition wall (120) within the fuel tank (102) can be modified depending upon a variation in shape of the fuel tank (102), size of the fuel tank (102), etc.

[0058] While specific language has been used to describe the disclosure, any limitations arising on account of the same are not intended. As would be apparent to a person in the art, various working modifications may be made to the method in order to implement the inventive concept as taught herein.

[0059] The figures and the forgoing description give examples of embodiments. Those skilled in the art will appreciate that one or more of the described elements may well be combined into a single functional element. Alternatively, certain elements may be split into multiple functional elements. Elements from one embodiment may be added to another embodiment. For example, orders of processes described herein may be changed and are not limited to the manner described herein. Moreover, the actions of any flow diagram need not be implemented in the order shown; nor do all of the acts necessarily need to be performed. Also, those acts that are not dependent on other acts may be performed in parallel with the other acts. The scope of embodiments is by no means limited by these specific examples.
, Claims:WE CLAIM:

1. A fuel tank system (100) of a vehicle (10), comprising:
a fuel tank (102) for storing the fuel, the fuel tank comprising a bottom wall (104); a first side wall (106) protruding from the bottom wall (104); a second side wall (108) protruding from the bottom wall (104); a top wall (110) interconnecting the first side wall (106) and the second side wall (108); a fuel filling unit (112) disposed on the top wall (110); and a cap selectively closing the fuel filling unit (112);
a fuel pump module (116) accommodated in the fuel tank (102), the fuel pump module (116) comprising a fuel entry inlet (118); and
a partition wall (120) extending in a width direction of the vehicle (10) from the bottom wall (104) of the fuel tank (102).

2. The fuel tank system (100) as claimed in claim 1, wherein the partition wall (120) is positioned behind the fuel entry inlet (118) of the fuel pump module (116) in a vehicle length direction.

3. The fuel tank system (100) as claimed in claim 2, wherein a distance between the partition wall (120) and the fuel entry inlet (118) as measured along the vehicle length direction is in the range of 0.1 mm to 10 mm.

4. The fuel tank system (100) as claimed in claim 1, wherein the partition wall (120) is positioned ahead of the fuel entry inlet (118) of the fuel pump module (116) in a vehicle length direction and a distance between the partition wall (120) and the fuel entry inlet (118) as measured along the vehicle length direction is in the range of 0.1 mm to 5 mm.

5. The fuel tank system (100) as claimed in claim 1, wherein the fuel tank (102) comprises a bulging portion (122) protruding from the bottom wall (104) and dividing the fuel tank (102) into a first portion (124) and a second portion (126), the first portion (124) comprising a first path (128), the second portion (126) comprising a second path (130); the fuel pump module (116) and the partition wall (120) are co-located in any one of the first path (128) and the second path (130).

6. The fuel tank system (100) as claimed in claim 5, wherein the partition wall (120) upon being located in the first path (128) or the second path (130) increases resistance of the fuel to flow in the length direction relative to the first path (128) or the second path (130) not having the partition wall (120) located therein.

7. The fuel tank system (100) as claimed in claim 6, wherein partition wall (120) creates a first wave pattern during forward flow of fuel in the length direction of the vehicle and a second wave pattern during a backward flow of fuel in the length direction of the vehicle.

8. The fuel tank system (100) as claimed in claim 1, wherein:
the partition wall (120) comprises a bottom edge (132), a first vertical edge (134) extending in an upward direction from the bottom edge (132), a second vertical edge (136) extending in an upward direction from the bottom edge (132) and being spaced apart from the first vertical edge (134); and a top edge (138) joining the first vertical edge (134) and the second vertical edge (136); and
the first vertical edge (134) being spaced apart from the first side wall (106) such that a distance between the first vertical edge (134) and the first side wall (106) is in the range of 0.01 to 5mm.

9. The fuel tank system (100) as claimed in claim 8, wherein the partition wall (120) comprises an aperture (140) between the first vertical edge (134) and the second vertical edge (136), such that the aperture (140) is proximate to the top edge (138) or terminates at the top edge (138) and wherein a dimension of the aperture (140) is less than a distance between the first vertical edge (134) and the second vertical edge (136).

10. The fuel tank system (100) as claimed in claim 9, wherein the aperture (140) is substantially aligned with the fuel entry inlet (118) in a vehicle length direction.

11. The fuel tank system (100) as claimed in claim 1, wherein fuel pump module (116) comprises a horizontal fuel pump module (116) comprising a fuel pump (142) and a fuel filter (144).