FORM-2
THE PATENTS ACT, 1970 The Patents Rules, 2003
COMPLETE SPECIFICATION
(SECTION 10 and RULE 13)
TITLE
MOUNTING STRUCTURE FOR FUEL TANK AND OIL TANK IN PASSENGER BODY OF AUTOMOTIVE VEHICLES OPERATING ON GASEOUS FUELS.
APPLICANT
We, Bajaj Auto Limited, an Indian Company, having its principal place of business at Akurdi, Pune - 411 035, State of Maharashtra, India, an Indian Company.
The following specification describes and ascertains the nature of this invention and the manner in which it is to be performed:-

This invention relates to mounting structure for fuel tank and oil tank on vehicles operating on gaseous fuels. This invention is particularly related to rear engine two-stroke three-wheeled passenger vehicles wherein the fuel tank is located within the passenger body behind passenger backrest.
Three wheeled vehicles are an important mode of transport in Indian scenario. Such vehicles are provided with either a two stroke or a four stroke engine working on Petrol or Diesel and the engine is located either at the rear within the passenger body or at the front below the drivers' seat. There are primarily two versions of such vehicles, which carry either 3 passengers or 6 passengers besides the driver. The passengers in these vehicles are accommodated on rear side of the driver, in one row for 3 passenger versions or two rows for 6 passenger versions. The seat for the driver is provided in a small cabin at the front of the vehicle, which may not have doors. The seats for the passengers are provided in a body manufactured primarily from sheet metal and seats are provided on the internally extended portion of the body. The engine mounted at the rear is covered by the same body portions from sides, which also has an externally openable lockable door at the rear to access the engine. These vehicles are well known.
In order to provide alternate to conventional fuels petrol or diesel, such vehicles have been converted to work on fuels like LPG or CNG. Use of these fuels provides a distinct economical advantage to the customer apart from being eco-friendly. The gaseous fuels are stored in gas cylinders mounted suitably on the vehicles and are refilled at the filling stations. In the event of non-availability of the filling stations at nearby location and when the gas is exhausted, the drivers face difficulty to run the vehicles. In order to avoid such difficulty, the engines provided on such vehicles can run alternatively on conventional fuels. Such operation, alternatively on conventional fuel, is widely known as 'limp home operation'. In order to facilitate such operation, the vehicle is provided with fuel tank. The fuel tank is mounted within the passenger body behind the passenger backrest and is accessible for filling from rear of the passenger body after opening the lockable rear door. The partition wall of body support the passenger backrest. Alternatively, the opening of the fuel tank for fuel filling is taken out from side of the passenger body. The engines operating on gaseous
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fuel on two-stroke principle also require separate lubricating oil to be fed for lubrication of parts like piston, cylinder etc. since the oil can not be mixed with gaseous fuel. This is achieved by providing separate oil pump and oil tank. The oil tank is located within the passenger body, behind passenger backrest, in which case, it is accessible after opening the lockable rear door. The mounting of the oil tank is away from the fuel tank and separate arrangement is provided for its attachment to vehicle part such as partition wall of the passenger body.
There are certain disadvantages associated with the known vehicles provided with fuel tank and oil tank mounted in the passenger body.
When the oil tank is mounted in the passenger body behind passenger backrest, away from the fuel tank, it needs additional brackets either welded to other vehicle part such as partition wall or corresponding mounting holes are required to be provided, which weakens such parts. The provision of the brackets, their assemblies also adds to cost.
When the oil tank is mounted on the part such as partition wall in the passenger body, its accessibility during re-filling is difficult.
Yet another disadvantage is that when the fuel tank filling is from the side wall opening and both fuel and oil are to be filled at the same station, the filling person has to access the openings from different places, which is time consuming.
OBJECTIVES OF THE PRESENT INVENTION
One of the objectives of the present invention is to provide a mounting structure for fuel tank and oil tank in passenger body, behind passenger backrest of automotive vehicles operating on gaseous fuels wherein both the tanks are located at proximity and are still accessible after opening only one door of passenger body.
Yet another objective of the present invention is to provide a mounting structure for fuel tank and oil tank in passenger body, behind passenger backrest of automotive
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vehicles operating on gaseous fuels wherein the proximity of the oil tank to fuel tank results in avoiding the use of separate brackets for oil tank mounting and possible weakening of the vehicle part such as partition wall is avoided.
BRIEF DESCRIPTION OF THE PRESENT INVENTION
In order to achieve above objectives, the applicants have provided a mounting structure for fuel tank and oil tank on automotive vehicles operating on gaseous fuels wherein the said fuel tank is fixed inside the passenger body behind passenger backrest and the oil tank is mounted above the fuel tank. The oil tank is clamped to fuel tank by fastening means. The openings for filling both the tanks are accessible after opening of rear door of the passenger body. Further, in order to avoid erroneous filling i.e. fuel in oil tank and oil in fuel tank means recognizable to filling persons such as different size of opening, different colors of opening or colours of tank etc. are provided.
The present invention will now be explained in detail with reference to the following figures enclosed with this provisional specification: -
Figure l - Illustrates the mounting of fuel tank and oil tank in passenger body of a three wheeler according to the prior art.
Figure 2 - Illustrates the mounting structures of fuel tank and oil tank in passenger body of a three wheeler according to the present invention.
Figure 3 - Illustrates detailed view of fuel tank and oil tank according to the present invention.
Figure 4 - Illustrates another detailed view of fuel tank and oil tank according to the present invention.
A mounting structure for fuel tank and oil tank in passenger body, behind passenger backrest of automotive vehicles operating on gaseous fuels according to the present
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invention essentially comprises of a passenger body (21), front and rear brackets (21a, 21b, 21c), a fuel tank (22) with integrally formed filling opening (23) and mounting lugs (28a, 28b, 28c) and oil tank clamping lugs (27a, 27b) and filling opening (25) and outlet (30), an oil tank (23) with integrally formed lugs (26a, 26b) and outlet (31), fuel tank fastening means (33) and oil tank clamping means (29).
The detailed description of mounting structure for fuel tank and oil tank in passenger body, behind passenger backrest of automotive vehicles operating on gaseous fuels according to the present invention has been made with reference to a typical rear engine three wheeled passenger vehicle.
Figure 1 illustrates a typical rear engine three-wheeled passenger vehicle operating on gaseous fuels. In this vehicle the fuel tank (11) is located in side the passenger body (12) behind passenger backrest (10a). The side wall (9) of the passenger body (12) is provided with opening (17) through which the fuel filling is done. There is provided a rear door (13), which is lockable and opens outwards. The figure also illustrates an oil tank (14) fixed on partition wall (10) of the passenger body (12), which is not at proximity of the fuel tank (11). The oil tank is fixed with the help of bracket (15) and fastening means (16). The mounting location of the oil tank is inconvenient for filling of the oil. Also since it is accessed after opening the rear door (13). Since it is well inside the body and cumbersome to reach. It can be observed that the fuel tank and oil tank needs to be accessed from different openings. Even in case the fuel tank is designed to have opening accessible through rear door (13), the access to oil tank is cumbersome.
With reference to the figures 2 to 4, in a mounting structure for fuel tank and oil tank behind passenger backrest in passenger body of rear engine three wheeled passenger vehicle, according to the invention, a fuel tank (22) with integrally formed filling opening (23) and mounting lugs (28a, 28b, 28c) and oil tank clamping lugs (27a, 27b) and outlet (30), is mounted inside the passenger body (21). The mounting lugs (28a, 28b, 28c) of fuel tank are clamped to brackets (21a, 21b, 21c) of suitable strength to carry load of both tanks and are fixed on walls of the passenger body (21) with the help of fuel tank fastening means (33). The filling opening (23) is directed
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towards rear door (34). The outlet (30) of fuel tank is connected to relevant part of the engine. An oil tank (24) with integrally formed lugs (26a, 26b) and outlet (31) is provided above the said fuel tank. Lugs (26a, 26b) of the oil tank and corresponding lugs (27a, 27b) provided on the fuel tank are clamped by oil tank clamping means (29). The filling opening (25) is directed towards the rear door (34). The outlet (31) of oil tank is connected to the oil pump of the engine. Both the filling openings (23) and (25) are closed by suitable caps (not shown). The oil level indicator sensor arrangement (32) is optionally fitted to the upper side of the oil tank. Both the fuel tank and oil tank are provided with closing caps (not shown).
It can be observed from the above description and the illustrations that the mounting structure for fuel tank and oil tank in passenger body of automotive vehicles operating on gaseous fuels provides that both the tanks are located at proximity, are still accessible easily and by opening of only rear door. Also the said mounting structure results in avoiding the use of separate brackets for oil tank mounting and avoids weakening of the vehicle parts such as partition wall of the passenger body.
Further, the tanks are manufactured either from non-metallic materials such as HDPE of suitable grade or from sheet metal.
While inventing the mounting structure for fuel tank and oil tank in passenger body of automotive vehicles operating on gaseous fuels according to the invention, care has been taken that it will satisfy all statutory requirements of vehicle fuel tank.
A mounting structure for fuel tank and oil tank in passenger body of automotive vehicles operating on gaseous fuels according to the present invention, as described herein and as illustrated in the drawings accompanying herewith and having variations and modifications are within the scope of the present invention. Such modification and variations are well within the knowledge skilled in the art without deviating from the scope of the invention.
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WE CLAIM:
1. A method for mounting a space saving fuel tank and an oil tank in a typical rear
engine three wheeled passenger vehicle operating on alternative non-
conventional fuel comprising of LPG or CNG and capable of operating also on
conventional fuel, having non-conventional fuel cylinder mounted beneath the
driver seat or beneath passenger seat, the conventional fuel tank and oil tank in
the passenger body behind the passenger back rest in the passenger body of the
vehicle, both accessible from openable rear door, said tanks typically a hollow
tank having an interior, suitable for inletting, storing and outletting, said method
comprising of:
a. mounting the said fuel tank fixedly within the passenger body behind passenger
backrest;
b. mounting the said oil tank fixedly on the fuel tank;
c. orienting the inlet of said fuel tank towards the rear door;
d. orienting the inlet of said oil tank towards the rear door;
e. terminating the inlet opening of the fuel tank, proximate to the rear door; and
f. terminating the inlet opening of the oil tank proximate to the rear door and
adjacent to the fuel tank inlet opening.
2. A space saving assembly of fuel tank and oil tank in a typical rear engine three
wheeled passenger vehicle operating on alternative non-conventional fuel
comprising of LPG or CNG and capable of operating also on conventional fuel,
having non-conventional fuel cylinder mounted beneath the driver's seat or
beneath passengers' seat, the conventional fuel tank and oil tank in the passenger
body behind the passenger back rest in the passenger body of the vehicle, both
accessible from openable rear door, said tanks typically a hollow tank having an
interior, suitable for inletting, storing and outletting, said tank comprising of:
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a. a front bracket (21a) and rear brackets (21b and 21c) on the walls of the passenger
body;
b. a fuel tank (22) having a filler opening (23), mounting lugs (28 a, b, c) and
holding lugs (27 a, b), wherein the filler opening (23) is oriented towards the rear
side and wherein the mounting lugs (28 a, b, c) are clamped to brackets (21 a, b,
c) correspondingly with fastening means (33); and
c. an oil tank (23) having a filler opening (25) mounted on top of the fuel tank (22)
and holding lugs (26 a, b), wherein the filler opening (25) is oriented towards the
rear side and wherein the holding lugs (26 a, b) are clamped to holding lugs (27 a,
b) of fuel tank with a clamping means (29);
d. such that said oil tank supported on the fuel tank; and
e. such that said fuel tank supported by the bracket onto the passenger body walls.
3. A space saving assembly of fuel tank and oil tank in a typical rear engine three wheeled passenger vehicle operating on alternative non-conventional fuel comprising of LPG or CNG and capable of operating also on conventional fuel, having non-conventional fuel cylinder mounted beneath the driver's seat or beneath passengers' seat, the conventional fuel tank and oil tank in the passenger body behind the passenger back rest in the passenger body of the vehicle, both accessible from openable rear door, said tanks typically a hollow tank having an interior, suitable for inletting, storing and outletting, said tank comprising of:
a. said passenger body having support structure comprising of plurality of brackets
(21a, b, c);
b. said fuel tank having a front wall, rear wall, side walls, a bottom wall, top wall, an
inlet opening and an outlet opening together forming an enclosure;
c. said top wall of fuel tank including an indentation;
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peripheral set of mounting lugs (28 a, b, c) positioned in a spaced relationship between said side walls;
e. said side walls of fuel tank including hold structure of plurality of projected
peripheral set of hold lugs (27 a, b) positioned in a spaced relationship between
said side walls;
f. said oil tank having side walls, a bottom wall, top wall, an inlet and an outlet
forming an enclosure;
g. said oil tank oriented within the said indentation on top wall of fuel tank;
h. said side walls of oil tank including hold structure of plurality of projected peripheral set of hold lugs (26 a, b) positioned in a special relationship between side walls;
i. said mounting lugs (28 a, b, c) of the fuel tank correspondingly to the mounting brackets (21 a, b , c) onto passenger body (21) orienting the inlet towards rear of the vehicle; and
j. said holding lugs (26 a, b) of oil tank and holding lugs (27 a, b) of fuel tank secure the oil tank onto fuel tank orienting the inlets towards the rear of the vehicle.
4. An arrangement for a space saving assembly of fuel tank and oil tank in a typical rear engine three wheeled passenger vehicle operating on alternative non-conventional fuel comprising of LPG or CNG and capable of operating also on conventional fuel, having non-conventional fuel cylinder mounted beneath the driver's seat or beneath passengers' seat, the conventional fuel tank and oil tank in the passenger body behind the passenger back rest in the passenger body of the vehicle, both accessible from openable rear door, said tanks typically a hollow tank having an interior, suitable for inletting, storing and outletting, said arrangement comprising of:
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a. a pair of tanks, an upper oil tank and a lower fuel tank, both tanks
substantially having a flat surface, short and quadrangle shaped together with
a substantial rectangular cross-section;
b. the said fuel tank and the oil tank are supported on a common single set of
brackets;
c. the said inlet of fuel tank and said inlet of oil tank are oriented substantially in
the same direction and in angular relationship;
d. the said fuel tank and oil tank are vertically mating;
e. the said indentation is formed integrally with the top wall of the fuel tank;
f. the said oil tank held on the top wall of fuel tank within the boundaries of
indentations defined by said walls of fuel tank;
5. A space saving assembly of fuel tank and oil tank as claimed in claims 1 to 4 characterized in having the inlet opening colour of said fuel tank different from the inlet opening colour of the oil tank.
6. A space saving assembly of fuel tank and oil tank as claimed in claims 1 to 4 characterized in having the tank colour of the said fuel tank different from the tank colour of the said oil tank.
7. A space saving assembly of fuel tank and oil tank as claimed in claims 1 to 4, wherein the fuel tank supports the oil tank.
8. A space saving assembly of fuel tank and oil tank as claimed in claims 1 to 4 characterized in having the inlet opening size of the said fuel tank different from the inlet opening size of the said oil tank.
9. A space saving assembly of fuel tank and oil tank as claimed in claims 1 to 4, wherein the oil tank is supported entirely on and by the fuel tank thereby eliminating mounting brackets of oil tank.
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10. A space saving assembly of fuel tank and oil tank as claimed in claims 1 to 4, wherein the side walls joining with the bottom wall and top wall are along the rounded edges.
11. A space saving assembly of fuel tank and oil tank as claimed in claims 1 to 4, wherein the said lugs extending away from the side walls.
12. A space saving assembly of fuel tank and oil tank as claimed in claims 1 to 4, wherein the said side walls are normally upright.
13. A space saving, assembly of fuel tank and oil tank as claimed in claims 1 to 4, wherein the said top walls are normally flat.
14. A space saving assembly of fuel tank and oil tank as claimed in claims 1 to 4, wherein the said bottom walls are normally flat.
15. A space saving assembly of fuel tank and oil tank as claimed in claims 1 to 4, wherein the said top wall and the bottom wall are generally parallel.
16. A space saving assembly of fuel tank and oil tank as claimed in claims 1 to 4, wherein the said tanks with a neck opening to define the filler opening and further having end caps to secure the opening.
17. A space saving assembly of fuel tank and oil tank as claimed in claims 1 to 4, wherein the oil tank is detachably mounted on the fuel tank.
18. A space saving assembly of fuel tank and oil tank as claimed in claims 1 to 4, wherein the hold lugs are provided such that one is provided at one side wall and second of the pair is provided at the opposing side wall.
19. A space saving assembly of fuel tank and oil tank as claimed in claims 1 to 4, wherein the support lugs are provided such that two are provided on rear wall and one at the front wall.
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20.A space saving assembly of fuel tank and oil tank as claimed in claims 1 to 4, wherein the oil tank is smaller in size and volume than the fuel tank.
21. A space saving assembly of fuel tank and oil tank as claimed in claims 1 to 4, wherein the top wall of fuel tank is configured to hold substantially atop on its top wall the oil tank and is contoured for oil tank to nest within.
22. A space saving assembly of fuel tank and oil tank as claimed in claims 1 to 4, wherein the front wall and the rear wall are of different width and are spaced.
23. A space saving assembly of fuel tank and oil tank as claimed in claims 1 to 4,
wherein the connection between the tanks and the inlets incorporates a neck tube
integrally moulded into the tank which opens into the interior of the tank, further
comprising atleast one independently moulded recess into the exterior surface of the
said tank, and one neck tube having a first end received within said recess of the tank
and second free end open as outlet filler mouth towards the rear of the vehicle.
Dated this the 29th day of August, 2006.
For Bajaj Auto Limited, By its Attorney,

(ARUNACHALAM APPAJI MOHAN)
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