A MODULAR PLASTIC FUEL TANK
Field of Invention
The object of the present invention is to provide a fuel tank for the effective utilization of the space available in a vehicle and the entire amount of fuel in the tank.
Background of the invention
A conventional fuel tank is shown in fig. 1. This type of tank is normally made of metal sheet preferably in a rectangular shape. This tank is fixed to the chasis of the vehicle using mounting brackets. As the mounting brackets protrude fi-om the tank, the vehicle manufacturers are facing difficulty in meeting with the required belly angle for a vehicle. This becomes a major drawback particularly when the vehicle has long wheel base with small tyres. On the other hard, the fuel tank should not be placed above the frame or chasis in a short wheel base vehicle. In order to meet this regulation, the manufacturers were forced to reduce the size of the fuel tank which considered to be a major disadvantage on the customer point of view.
In an attempt to overcome the above drawback, one or more undercut along the entire surface of the tank is formed to hold or locate the mounting brackets as shown in fig. 2. This approach resulted in the increase of the volume of the fuel tank. However, the undercut provided in the bottom wall of the tank divided the tank into more than one compartment. The flow of fuel from one compartment to another compartment is blocked by the undercut This results in substantial amount of unused or dead fuel.

DE 2551073 discloses a process for manufacturing sheet metal canisters consisting primarily of two shells obtained by deep-drawing and welded with one another along a rurming around, counter-sunk seam flange and as well as a die or mould to implement this procedure.
JP 10-324164 discloses a metallic fuel tank with a flange which does not act as a obstructive element thereby removing the dead space occupied by the flange.
However there is a need to develop a plastic fuel tank which can utilize the space available in a vehicle and allow usage of entire amount of fuel in the tank.
Object of the invention
The object of the present invention is to provide a fuel tank which utilizes the space available in the vehicle effectively as well as the entire amount of fuel in the tank, i.e. zero unused or dead fiiel.
Accordingly, the present invention provides a modular plastic fuel tank comprising a closed body formed by a top wall, a bottom wall, a front wall, a rear wall and two side walls; an inlet for filling the fuel; and outlet for supplying the fuel to an engine; at least one open ended hollow pillar extending from the top wall to the bottom wall and located closer to one of the side walls; a mounting strip guide extending from one end of the hollow pillar to the other end of the hollow pillar along the top wall, the side wall which is away from the hollow pillar and the bottom wall thereby creating a passage for the entire amount of fuel to move freely inside the tank; and at least one baffle extending from the bottom wall for controlling the impact of the fuel during movement of the vehicle, the length of the baffle being smaller than the width of the tank and the height of the baffle being smaller than the height of the tank.

Brief description of the drawings :
Fig. 1 shows a conventional fuel tank which is mounted using brackets.
Fig. 2 shows another conventional fuel tank formed with undercut for the
mounting brackets.
Fig. 3 shows a perspective view of the fuel tank according to the present
invention.
Fig. 4 shows a cross sectional view of the tank of the present invention taken along
the horizontal axis.
Fig. 5 shows a cross sectional view of the present invention taken along the
vertical axis.
Fig. 6 shows a preferred embodiment of the fuel tank of the present invention.
Fig. 7 shows a bottom view of the fuel tank of the present invention.
Detailed description of the drawings.
The fuel tank of the present invention is preferably in rectangle shape as shown in fig. 3.The tank has one inlet (10) for filling the fuel and one outlet (15) through which the fuel is supplied to the engine. The fuel level sensor can be integrated with the outlet (15), The tank comprises a closed body formed by a top wall (20), a bottom wall (30), two side walls (40a, 40b), a front wall (50) and a rear wall (60). The tank further comprises two hollow pillars (25) connecting the top wall (20) to the bottom wall (30) and located closer to one of the side wall (40b) which is away from the chassis when the tank is fixed to the vehicle. The ends of the hollow pillars (25) are open. The ends of the hollow pillar are connected by a mounting strip guide (35) which extends along part of the top wall (20), the side wall (40a), which is away from the pillar and part of the bottom wall (30). The hollow pillar (25) and the mounting strip guide (35) arrangement creates a passage (70) as shown in figure 5 for the fuel to move freely from one end of the tank to the other end of the tank. This enables utilization of the entire amount of fuel in

the tank resulting in zero unused / dead fuel. This pillar arrangement which is clearly shown in figures 4 and 5 provides additional rigidity to the tank.
The tank of the present invention also comprises a baffle (65) as shown in fig. 5 to take care of the impact load due to splashing of fuel during the vehicle movement particularly during braking. The baffle extends from the bottom wall and placed between the hollow pillars (25) and the side wall (40a) which is away from the hollow pillar (25) so that the passage (70) is not blocked. The height of the baffle (65) is nearly half the height of the tank. It is also possible to have baffles(85) extending from the side walls (40a, 40b) as shown in fig, 6 without blocking the passage (70).
In a preferred embodiment, stiffeners (80) are formed on the side walls (40a, 40b), front wall (50) and rear wall (60) for strengthening the tank as shown is figure 3. In another preferred embodiment, stiffeners (65a) may be provided to support the baffle (65) as shown in figure 5. At least one drain hole (90) is provided in the bottom wall (30) adjacent to the side wall (40a) as shown in figure 7. It is preferable to have two drain holes (90), one being located near to the comer of the bottom wall (30), front wall (50) and the side wall (40a) and the other being located near to the comer of the bottom wall (30), rear wall (60) and the side wall (40a). This drain hole can be used to inter connect the adjacent tanks when more than one tank is mounted in a vehicle. The drain hole is constmcted in such a way that the interconnection of two tanks does not protmde below the bottom wall (30),
The fuel tank of the present invention is fixed to the chasis of the vehicle using mounting bracket and mounting strip which mns along the mounting strip guide (35) and pass through the hollow pillar (25). This results in reduction in the amount of material needed for mounting the tank thereby reduction in the cost as well as in the weight of the vehicle.

The fuel tank designed according to the present invention can hold more volume of fuel compared to the conventional fuel tank designed for the given dimension. The fuel tank of the present invention can be mounted anywhere between the wheel bases without violating any regulations for almost all range of medium and heavy vehicles.
Further, plurality of fuel tanks of the present invention, which are interconnected with each other, can be mounted in the vehicle to increase the fuel capacity of the vehicle. The fuel tank of the present invention can be made in different sizes depending upon the requirement.

WE CLAIM :
1. A modular plastic fuel tank comprising a closed body formed by a top wall (20), a bottom wall (30), a front wall (50), a rear wall (60) and two side walls (40a 40b); an inlet (10) for filling the fuel; and outlet (15) for supplying the fuel to an engine; said fuel tank characterized by at least one open ended hollow pillar (25) extending from the top wall to the bottom wall and located closer to one of the side walls (40b); a mounting strip guide (35) extending from one end of the hollow pillar to the other end of the hollow pillar along the top wall (20), the side wall (40a) which is away from the hollow pillar and the bottom wall (30) thereby creating a passage (70) for the entire amount of fuel to move fi-eely inside the tank; and at least one baffle (65) extending from the bottom wall for controlling the impact of the fuel during movement of the vehicle, the baffle being located between the hollow pillar and the side wall (40a) and the height of the baffle being smaller than the height of the tank.
2. The tank as claimed in claim 1, wherein at least one drain hole (90) is provided in the bottom wall.
3. The tank as claimed in claim 1, wherein two drain holes are provided in the bottom wall.
4. The tank as claimed in claims 1 to 3, wherein the drain hole in the bottom wall in adjacent to the side wall (40a).
5. The tank as claimed in claim 1, comprising one or more baffle (85) extending from the side walls.

6. The tank as claimed in claim 1, comprising two hollow pillars the ends of
each of the hollow pillars are connected by separate mounting strip guide.
7. The tank as claimed in claim 1, wherein a fuel level sensor is integrated with
the outlet.
8. The fuel tank as claimed in claim 1, wherein stiffeners (80) are provided on
the walls of the tank for strengthening the tank.
9. The fiiel tank as claimed in claim 1, wherein stiffeners (65a) are provided to
support the baffle (65).