TECHNICAL FIELD
[0001] The present subject matter relates to a saddle type two or
three-wheeled vehicle. More particularly, the present subject matter relates to a fuel pump module and method for installing the same inthe vehicle.
BACKGROUND
[0002] Saddle type two and three-wheeled vehicles are one of .the most
affordable forms of motorized transport and for most of the world's population ' they are the most common type of motor vehicle. The majority of these vehicles are powered by two-stroke and four stroke engines. For many years, a fuel supply system of the conventional spark-driven internal combustion engine has used a carburetor to deliver fuel into the engine. The primary function of carburetor is to provide the air-fuel mixture to the engine in the required proportion.
[0003] In recent years, there has been requirements for the two-wheeled
vehicle to discharge an exhaust gas containing low harmful component for environment and to be operated with improved fuel economy, and in accordance with such requirement, a fuel supply system utilizing a fuel injection unit has been developed. In such vehicle, it is necessary to feed, under pressure, the fuel in the fuel tank into the fuel injection unit disposed on the engine side, and therefore, a fuel pump module is mounted to the fuel tank.
[0004] In a known saddle type vehicle, a typical electronic fuel injection
system comprises a fuel tank, a high-pressure fuel pump that is operatively
coupled to the fuel tank that directs fuel into the engine. Further, as an
improvement over the carburetor, the electronic fuel injection system (EFT)
utilizes modern electronic techniques to adjust the air fuel mixture. Hence, as
engines moved away from carburetors and towards fuel injection, the conversion
of the carburetor to the electronic fuel injection system (EFT) involves many
electrical and mechanical modifications in the vehicle. For example, the fuel
supply system in the carburetor based vehicle includes the low pressure fuel pump __

whereas the electronic fuel injection system (EFI) operate more efficiently at higher fuel pressures and hence includes a high pressure electronic pump. Thus, in order to convert from a conventional carburetor system to the Electronic Fuel Injection (EFI) system, the low pressure pump in the carburetor system needs to be replaced by a high pressure pump.
[0005] In an existing vehicle, a fuel pump module is arranged inside of a fuel
tank which stores fuel therein. This type of fuel tank is an in-tank pump type. The vehicle includes a single main frame which extends rearwardly from a head pipe. The fuel tank is arranged on the main frame with a fuel pump being mounted on either one of a pair of left and right tank portions of the fuel tank. The arrangement includes a fuel pump for pumping fuel to the engine, and a filter for filtering fuel prior entering the fuel pump.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] - The detailed description-is described with reference'to the accompanying figures. The same numbers are used throughout the drawings to reference like features and components.
[0007] Fig.l is a side view of a two-wheeled vehicle as per one embodiment
of the present invention
[0008] Fig.2 is a perspective view of a fuel tank illustrating a fuel level
detection level unit and a fuel pump mounted on at least a portion of an inner member of the fuel tank, as per one embodiment of the present invention.
[0009] Fig.3 is a perspective view of said inner member of the fuel tank of
the two-wheeled vehicle of Fig. 1, as per one embodiment of the present invention.
[00010] Fig.4 is a longitudinal sectional view taken along line 1-1 in Fig. 2, as per one embodiment of the present invention.
[00011] Fig.5 is a perspective view of the inner member of the fuel tank of the Fig.l illustrating mounting of the fuel level detection unit and the fuel pump on.an inner bottom wall thereof, as per one embodiment of the present invention.

DETAILED DESCRIPTION
[0001] An existing saddle type vehicle which employs an electronically
controlled fuel injection system includes a fuel system with a fuel tank, a fuel pump that pumps fuel from the tank to a vehicle engine to support operation of the engine, and various other components, such as a fuel level detection unit, fuel pressure regulator, fuel injectors, fuel filter, canister and the like.
[0002] Conventionally, in a saddle type vehicle with an electronic fuel injection system, a fuel tank is mounted on a vehicle body frame in such a way that it sits astride a vehicle body frame in the direction of the width of a vehicle ' body. Thus, the position where a flange can be secured for mounting a fuel pump is limited to only the bottom surfaces along both sides of the vehicle body frame. Hence, a freedom of arranging the fuel pump within the fuel tank of the vehicle is . greatly obstructed, for the reason of being mounted to a frame of the vehicle.
[0003] In a known saddle type vehicle, the fuel pump module is mounted
within the vehicle fuel tank as part of an assembly that may include other components of the fuel system, such as the fuel level detection unit, one or more fuel filters and the canister. However, some fuel tanks may have a limited depth or other constructions and limitations that make it difficult to insert a fuel pump module that includes full size accessories or components into the fuel tank. In some applications, reducing the size of the components, for example a fuel reservoir in which the fuel pump module is received, or a fuel filter, is not desirable since the performance of the fuel pump module may be diminished.
[0004] In another known saddle type vehicle, a method for mounting the fuel
pump module is intended to be changed from the existing type using a carburetor to a fuel injection system, such that when there is little fuel left in the tank it is easily sucked into the pump, making it to effectively use the fuel and hence substantially reducing or eliminating dead volume remaining in the fuel tank. Often, manufacturers have a need for having flexibility of carburetor as well as fuel injection system variants to be made for the same vehicle depending on the market requirements within same country and across countries. Cost factors,

manufacturing variety reduction also pose challenge in achieving multi-model flexibility to be able to switch from carburetor type to injection type & vice versa. However, in such saddle type vehicle with an electronically controlled fuel injection engine, the U-shaped inner member of the fuel tank which typically is formed owing to the main frame member passing through does not provide for a sufficient plane for mounting a fuel pump. Further, the space provided in a bottom surface of the fuel tank is limited' and hence can accommodate one or more components which can function effectively only when positioned at a location in at least a portion of said bottom surface of the inner member of the fuel tank. For example, the fuel level detection unit has to be mounted at a predetermined height within the inner member of the fuel tank so as to ensure detecting the fuel level in a sufficiently wide range and minimize dead volume of fuel. Thus, due to space constraint in the fuel tank to mount a fuel pump therein, acceptable fuel pump module fitting locations is very limited
[0001] Thus, the conventional design for the fuel tank of the saddle type vehicle have numerous constraints that often lead to difficulty in designing, assembling, and servicing the fuel pump module when converting from a carburetor to an electronic fuel injection system. Further, due to numerous shaped features to tightly fit the fuel tank to the vehicle, acceptable fuel pump module fitting locations is very limited and may not be at or near the fuel tank opening for easy access / service.
[0005] Hence, it is desirable to improve the conventional structure of the fuel
tank for the saddle type vehicle in the manner so as to accommodate the electrical and mechanical changes involved in the effective conversion of the carburetor system to the Electronic Fuel Injection system (EFI) without compromising the capacity of the fuel tank and further to simplify the overall electronic fuel system design, provide a modified system that ensures that the fuel is-always delivered to the engine on demand, monitor or vary the air to fuel ratio to account for different operating or atmospheric conditions and in addition provides better performance with improved fuel economy. Accordingly, to configure the fuel pump in a rear

portion in the inside of the tank, it is necessary to change the design & shape of the fuel tank.
[0001] With the above objectives in view, the present invention provides an
improved structure for the vehicle fuel tank configured for mounting said fuel pump on at least a portion therein without compromising the capacity of the fuel tank and in addition, substantially reducing the dead volume of the fuel tank as • well as resolving all the above problems & other issues in the known art. Particularly, in one embodiment, an improved design for the vehicle fuel tank comprises a inner member including a flat plane on which said fuel pump is positioned along a center portion of said inner member of the fuel tank such that said fuel pump is disposed at a position lower than a fuel detection unit, thereby facilitating easy and compact configuration of said fuel pump module in the fuel tank and in addition ensuring at least a substantially reduced residual or dead volume remaining in the fuel tank.
[0002] According to one embodiment of the present invention, a saddle type
vehicle comprises a front wheel and a rear wheel generally positioned in line with the front wheel along a longitudinal plane of the vehicle, a frame supported by the front wheel and the rear wheel, an engine coupled to the frame and operably coupled to the rear wheel to power the rear wheel and a fuel tank mounted on the frame and operably coupled to the engine. In one embodiment, the fuel tank includes.an outer member.and an inner member. The outer.member and said inner member being inverted U-shaped and joined at their edges to form a closed U-shaped fuel space, a fuel pump module configured for supplying fuel from the fuel tank to an engine and a fuel level detection unit adapted for detecting the level of fuel in the fuel tank. Referring to one embodiment, a front portion of said inner member includes a contour profile terminating in a rearwardly downwardly inclined section along a width of the vehicle. In one embodiment, a rear portion of said inner member continued rearwardly from said front portion includes a flat plane extending along said vehicle front-rear direction. As per one embodiment, the fuel level detection unit mounted in at least a portion of said inclined section

and said fuel pump module disposed on at least a portion of said flat plane are aligned at a predetermined angle to one another. In one embodiment, the fuel level detection unit mounted on said at least a portion of the inclined section and the fuel pump module disposed on said at least a portion of said flat plane are aligned with one another at said predetermined angle 0 in a range of 90° to 120 ° with respect to vehicle longitudinal axis. Further, the fuel pump module disposed on said at least a portion of said flat plane along a center portion of the inner member with respect to the direction of the width thereof, is positioned opposed to the inclined section of said front portion of said inner member. Further, referring to one embodiment, said contour profile of said inner member includes a substantially upwardly extending curved portion, a rearwardly extending substantially horizontal portion continued from said curved portion and said rearwardly downwardly extending said inclined section continued from said horizontal portion. Further, as per one embodiment, at least one opening area formed on said at least a portion of said inclined section and said at least a portion of said flat plane is adapted to dispose said fuel detective unit and said fuel pump module therein, respectively. In one embodiment, said fuel pump module is disposed at a lower position than the fuel level detection unit.
[0003] Further, one embodiment of the present invention relates to a method of installing said fuel pump module and said fuel level detection unit in the vehicle fuel tank having said at least one opening. In one embodiment, said method comprising steps of providing said fuel pump module, providing said fuel level detection unit having an elongate sensor body, mounting the fuel level detection unit in said inclined section of the inner member of the fuel tank by inserting said fuel level detection unit in a first opening of said at least one opening and arranging the fuel pump module in the flat plane of said inner member of the fuel tank by inserting said fuel level detection unit in a second opening of said at least one opening at said predetermined angle (9) with said fuel level detection unit.
[0004] An object of the present invention is to provide an improved fuel tank structure for the saddle type vehicle. In one embodiment, said improved structure

for the inner member of said fuel tank is configured to include said flat plane such that, mounting the fuel pump module is easily ensured and additionally the fuel pump module is disposed on said at least a portion of said flat plane of the inner member without increasing a width of the fuel tank.
[0005] As per one embodiment of the present invention, the inner member of
the fuel tank is structurally configured to include said flat plane for mounting the fuel pump on said at least a portion therein. Particularly, as per one embodiment, said said second opening of said at least one opening is formed on said flat plane of said rear portion of the inner member of the vehicle fuel tank such that said fuel pump mounted to said second opening is positioned opposed to said inclined section of said front portion of said inner member of said vehicle fuel tank.
[0006] The present invention relates to an improved structure for the vehicle
fuel tank mounted on the vehicle in the front-to-rear direction of the vehicle. In one embodiment of the present invention, wwl inner member of the fuel tank comprises the flat plane elongated in the front-to-rear direction; and the fuel pump • module installed in the fuel tank by inserting the fuel pump module into the fuel tank through said inner bottom wall of the inner member of the fuel tank;
[0007] Various other features and advantages of the invention are described in detail below with reference to the accompanying drawings. In the drawings, like reference numbers generally indicate identical, functionally similar, and/or structurally similar elements. The drawing in which an element first appears is indicated by the leftmost digit(s) in the corresponding reference number. With reference to the accompanying drawings, wherein the same reference numerals will be used to identify the same or similar elements throughout the several views. It should be noted that the drawings should be viewed in the direction of orientation of the reference numerals.
[0008] It is to be noted that in the ensuing description, the present invention is
usable in a saddle type vehicle exemplified in the form of a. two wheeled scooter type motorcycle for illustration.

[0009] Further "front" and "rear", and "left" and "right" referred to in the ensuing description of the illustrated embodiment refer to front and rear, and left and right directions as seen in a state of being seated on a seat of the motorcycle type vehicle. Furthermore, a longitudinal axis refers to a front to rear axis relative to the vehicle, while a lateral axis refers to a side to side, or left to right axis relative to the vehicle. 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.
[00010] Fig.l is a side view of the two-wheeled vehicle (100) (hereinafter 'the vehicle'), as per one embodiment of the present invention. According to one embodiment of .the present invention, the vehicle (100) comprises a front body portion (F) and a rear body portion (R). In the front portion (F) of the vehicle (100), a steering shaft (not shown) is supported rotatably in a certain range. Further, a handlebar (105) is rotatably integrally connected to the steering shaft for steering the vehicle (100) and is connected to a front wheel (108) through the steering shaft. A steering handle (not shown) is rotatably supported, independently of a front fork assembly (106), on a steering stem. An upper portion of the front wheel (108) is covered by the front fender (107) which prevents mud and water from getting deflected towards the steering shaft. The front wheel (108) is rotatably mounted on the front portion (F) thereof and a rear wheel (116) is rotatably mounted on a rear portion (R) thereof. A rear fender (115) is located above the rear wheel (116) so as to cover a portion of the outer periphery of the rear wheel (116) with its associated tire. The portion covered is selected to prevent water, mud and other unwanted material from being delivered from the rear wheel (116). Further, the front fork assembly (106) is mounted over the front fender (107). In a portion lying ahead of the front fork assembly (106), a lighting device such as a headlamp (103), a. pair of signaling devices such as turn signal lamps (not shown), a display device such as a speedometer (not shown) are housed by a holding structure (not shown) mounted thereto. An adjustable windscreen (103) is mounted to the front of the vehicle (100). A pair of rear view mirror (104) comprises a casing, the casing having a front mirror fnr reflprtina HIP imam* ^f

traffic approaching from behind. A two-legged stand (112) is used to support and hold the vehicle (100). The stand (112) moves on a pivot (not shown) to take up two positions, one folded up and the other on the ground.
[00011] Further in Fig.l, said vehicle (100) comprises a frame (118) extending along a vehicle longitudinal axis (AA). In one embodiment, the fuel tank (109) is mounted on the frame (118) in a vehicle front-rear direction. Particularly, in the front portion (F) of the vehicle (100), the fuel tank (109) is disposed partially engulfing the frame and over an internal combustion engine (111). A seat assembly (110) is disposed immediately behind the fuel tank (109). A pillion (114) is disposed rearwardly of the seat assembly (110). Suspension systems are provided for comfortable steering of the vehicle (100) on the road. The front fork assembly (106) forms the front suspension system and serves as a rigidity component. Further, a rear suspension system, which is a hydraulic damped arrangement, includes a spring-shock absorber unit (113) at the rear body portion (R) of the vehicle (100). Further, the engine (111) is equipped with an exhaust system that includes an exhaust pipe (not shown) connected to the engine (111) and a muffler (not shown) connected to the exhaust pipe. The muffler (not shown) extends rearwards along the right side of the rear wheel (116).
[00012] Fig.2 is a perspective view of the fuel tank (109) including an outer member (109a) and an inner member (109b), said outer member (109a) and said inner member (109b) being substantially inverted U-shaped and joined at their edges to form said closed U-shaped fuel space and the shape partially engulfs the main tube of the frame .structure. In one embodiment, said fuel pump module (203) is configured for supplying fuel from the fuel tank (109) to said engine (111); . and the fuel level detection unit (204) adapted for detecting the level of fuel in the fuel tank (109) are disposed on at least a portion of said inner member (109b) of said fuel tank (109). In one embodiment, the fuel level detection unit (204) comprises an elongate sensor body (204a). As per one embodiment, said fuel pump module (203) is disposed at a lower position than the fuel level detection unit (204).

[00013] Fig-3 is a perspective view of said inner member (109b) of the fuel tank (109) of the vehicle (100) of Fig.l, as per one embodiment of the present invention. In one embodiment, the front portion (F') of said inner member (109b) includes said contour profile. The contour profile (200) of said inner member (109b) is a sequentially configured to have four stage sub-contoured profiles and includes said substantially upwardly extending curved portion (200a) also referred as first sub-contour, said rearwardly extending substantially horizontal portion (200b) also referred as second sub-contour continued from said curved portion (200a) and said rearwardly downwardly extending said inclined section (200c) also referred as third sub-contour continued from said horizontal portion (200b). Particularly, as per one embodiment, the contour profile (200) in said front portion (F') of said inner member (109b) terminates in the rearwardly downwardly inclined section (200c) along the length of the vehicle (100). In one embodiment, the rear portion (R') of said inner member (109b) continued rearwardly from said front p_ortion„(E') includes, the flat.plane (200d) also .referred as. fourth sub-contour extending along said vehicle front-rear direction. Further, in one embodiment, the fuel level detection unit (204) is mounted in said at least a portion of said inclined section (200c) and said fuel pump module (203) is disposed on said at least a portion of said inclined section (200c). Further, in one embodiment, said at least one opening area (201), (205) formed on said at least a portion of said inclined section (200c) and said at least a portion of said flat plane (200d) is adapted to dispose said fuel detection unit (204) and said fuel pump module (203) therein, respectively. As per as aspect of the present subject matter, the fuel pump module (203) opening (205) may be coupled with a carburetor module to enable supply of fuel to the engine. The flat plane (200d) serves meeting a dual purpose of configuring a fuel injection system when using an EFI (Electronic Fuel Injection) system for a' vehicle and can be easily re-configured to mount a carburetor system for a carburetor type vehicle. As per an aspect of the present subject matter each of the multi stage sub-contours of the sequentially contoured profile may be connected with suitable fillet or chamfer type sections (not shown) between each of the sub-contours as well as end portion of the first and the last sub-contour.

[00014] Fig.4 is a longitudinal sectional view taken along line 1-1 in Fig. 2, as per one embodiment of the present invention. In one embodiment of the present invention, said fuel tank (109) includes said outer member (109a) and said inner member (109b). In one embodiment, said outer member (109a) and said inner member (109b) being substantially inverted U-shaped are joined at their edges to form the closed U-shaped fuel space. As per one embodiment, said fuel level detection unit (204) mounted in said at least a portion of said inclined section (200c) of said inner member and said fuel pump module (203) disposed on said at least a portion of said inclined section (200c) of said inner member (109b) are aligned at a predetermined angle (G) to one another. Particularly, the fuel level detection unit (204) and the fuel pump module (203) positioned on at least apportion of said inner member (109b) of the vehicle fuel tank (109) are aligned with one another at said predetermined angle (0) in a range of 90 to 120 °. In one embodiment of the present invention, said fuel pump module (203) is disposed at said lower position than the fuel level detection unit (204).
[00012] Fig.5 is a perspective view of the inner member (109b) of the fuel tank (109) of the Fig.l illustrating mounting of the fuel level detection unit (204) and the fuel pump module (203) on an inner bottom surface (207) therein, as per one embodiment of the present invention. In one embodiment, the fuel pump module (203) is disposed on said at least a portion of said flat plane (200d) along said center portion of the inner member (109b) with respect to the front rear direction of the vehicle thereof. Particularly, as per one embodiment, said fuel pump module (204) is positioned opposed to the inclined section (200c) of said front portion (F') of said inner member (109b). In one embodiment, said fuel pump (203) is mounted to said inner member (109b) of said fuel tank (109) by a mounting flange (203a) received in a second opening of said at least one opening (201), (205) in said at least a portion of said inner member (109b) of the fuel tank (109) and secured to said inner bottom surface (200) thereof. As per another embodiment of the present subject matter, the first & second sub-contours (200a), (200b) may be combined to form a single continuous contour thereby resulting in

the inner member (109b) being configured to be made of sequentially configured 4 stage sub-contoured profile.
[00015] Advantageously, as per one embodiment, the present invention relates to the improved structure for the inner member of the fuel tank of the vehicle being configured for mounting one or more components including the fuel pump and the fuel level detection unit on said at least a portion therein. In one embodiment, said inner member includes the inclined section configured for arranging said fuel pump module on said at least a portion therein such that said fuel pump module'is inclined at the predetermined angle with said fuel level detection unit in order to direct an optimal amount of fuel to the engine to ensure efficient operation of the engine. Additionally, as per one embodiment, the arrangement of said fuel pump module on said flat plane of said inner member facilitates in substantial reduction or elimination of the dead volume which may exist in the fuel tank volume between the inner member and outer member of the ' fuel tank and further results in greater ease of assembling the fuel pump module in the limited space available in said inner member of the fuel tank of the vehicle. Thus, as per the present subject matter the improved design of the inner member of the fuel storage unit is so configured to have flexible fuel storage unit which is capable of being assembled with a carburetor type system or a fuel injection type system with least difficulty, ease of assemble, no major compromise in the fuel volume, low dead fuel volume as well as ease of service. Such a sequentially configured at least one stage sub-contour inner member design of a fuel storage unit enables overcoming cost challenges as well as achieve multi-model variety between carburetor and fuel injection type systems.
[00016] Improvements and modifications may be incorporated herein without deviating from the scope of the invention.

We claim:
1. A saddle type vehicle (100), said vehicle (100) comprising:
a frame (118) extending along a vehicle longitudinal axis (AA);
a fuel .tank (109) mounted on the frame (118) in a vehicle front-rear
direction, said fuel tank (109) including an outer member (109a) and an
inner member (109b), said outer member (109a) and said inner member
(109b) being substantially inverted U-shaped and joined at their edges to
form a closed U-shaped fuel space;
a fuel pump module (203) configured for supplying fuel from the fuel tank
(109) to an engine (111); and
a fuel level detection unit (204) adapted for detecting the level of fuel in
the fuel tank (109);
wherein a front portion (F') of said inner member (109b) includes a
sequentially configured at least one contour profile (200) having a
rearwardly downwardly inclined section (200c) along a length of the
vehicle' (100); and wherein a rear portion (R') of said inner member (109b)
continued rearwardly from said front portion (T') includes a flat plane
(200d) extending along said vehicle front-rear direction.
2. The saddle type vehicle (100) as claimed in claim 1, wherein said fuel level detection unit (204) is mounted in at least a portion of said inclined section (200c) and said fuel pump module (203) is disposed on at least a portion of said flat plane (200d).
3. The saddle type vehicle (100) as claimed in claim 1, wherein said fuel level detection unit (204) and said fuel pump module (203) are aligned with one another at a predetermined angle (0) in a range of 90 to 120 °.
4. The saddle type vehicle (100) as claimed in claim 1, wherein the fuel level detection unit (204) mounted on said at least a portion of the inclined section (200c) and the fuel pump module (203) disposed on said at least a portion of said flat plane (200d) are aligned with one another at said predetermined angle (9) in a range of 90 to 120 °.

5. The saddle type vehicle (100) as claimed in* claim 1, wherein the fuel pump module (203) disposed on said at least a portion of said flat plane (200d) along a substantially center portion of the inner member (109b) with respect to the width direction of the vehicle thereof & is positioned opposed to the inclined section (200c) of said front portion (F') of said inner member (109b).
6. The saddle type vehicle (100) as claimed in claim 1, wherein at least one opening area (201), (205) formed on said at least a portion of said inclined section (200c) and said at least a portion of said flat plane (200d) is adapted to dispose said fuel level detection unit (204) and said fuel pump module (203) therein, respectively.
7. The saddle type vehicle (100) as claimed in claiml, said fuel pump module (203) is disposed at a lower position than the fuel level detection unit (204).
8. A saddle type vehicle (100), said vehicle (100) comprising:
a frame (118) extending along a vehicle longitudinal axis (AA); a fuel tank (109) mounted on the frame (118) in a vehicle front-rear direction, said fuel tank (109) including an outer member (109a) and an inner member (109b), said outer member (109a) and said inner member (109b) being substantially inverted U-shaped and joined at their edges to form a closed U-shaped fuel space,
wherein said inner member (109b) includes a sequentially configured multi contoured profile (200); and wherein said sequentially configured multi contoured profile (200) includes a substantially upwardly extending curved portion (200a), a rearwardly extending substantially horizontal portion (200b) continued from said curved portion (200a) and said rearwardly downwardly extending said inclined section (200c) continued from said horizontal portion (200b).

9. A method of installing a fuel pump module (203) and a fuel level detection unit (204) in a vehicle fuel tank (109b) having at least one opening (201), (205), said method comprising steps of:
providing a fuel pump module (203);
providing a fuel level detection unit (204) having an elongate sensor body
(204a);
mounting the fuel level detection unit (204) in on inclined section (200c) of an inner member (109b) of the fuel tank (109) by inserting said fuel level detection unit (204) in a first opening (201) of said at least one opening (201), (205); and
arranging the fuel pump module (203) on a flat plane (200d) of said inner member (109b) of the fuel tank (109) by inserting said fuel level detection unit (204) in a second opening (205) of said at least one opening (201), (205) at a predetermined angle (9) with said fuel level detection unit (204).