AU637311B1

AU637311B1 -

Info

Publication number: AU637311B1
Application number: AU3401893A
Authority: AU
Priority date: 1993-03-04
Filing date: 1993-03-04
Publication date: 1993-05-20
Anticipated expiration: 1999-03-04

Description

42835PP PJW:PFB 6J31 1 P/00/012 Regulation 3.2

AUSTRALIA

Patents Act 1990 COMPLETE SPECIFICATION FOR A PETTY PATENT

ORIGINAL

Name of Applicants: NEIL STANLEY BOWLEY AND MICHAEL ALLAN PAGE Actual Inventors: NEIL STANLEY BOWLEY AND MICHAEL ALLAN PAGE Address for Service: COLLISON CO. 117 King William Street, Adelaide, S.A. 5000 Invention Title: A FUEL STORAGE ARRANGEMENT The following statement is a full description of this invention, including the best method of performing it known to us: This invention relates to a fuel tank arrangement and method of fixing a fuel tank to a vehicle.

It has become popular to run vehicles on a configuration of gas known as Liquid Petroleum Gas (LPG), because of the lower cost of LPG. In order to do so it is necessary to convert vehicles which are designed for petrol to run on LPG. The conversion process does not convert vehicles to run solely on LPG and it is desired to give the vehicle dual fuel capacity, in part because it is 1 0 desired to at least start the vehicle with petrol, and in some circumstances such as where it is desired to provide for more power, the engine is best driven under petrol.

One of the major steps in the conversion process is fitting a specifically 1 5 designed LPG fuel tank. The LPG fuel tank is one that can withstand high pressures and industry standards provide for a cylindrical tank with hemispherical ends, to maximise strength. In many vehicles the LPG fuel tank is fitted in addition to the existing fuel tank with a consequent loss of space.

Generally with the configuration of vehicle known as a sedan, such a fuel tank is fitted into the boot or trunk of the vehicle, with less space being available therein. In the configuration of vehicle known as a station wagon, or estate wagon, the fuel tank is often fitted behind the rear seat in the rear of the 2 vehicle.

That position is not especially desirable because, firstly, the fuel tank is visible and unsightly. Secondly station wagons are generally purchased because of the greater room available, which room is substantially reduced by the provision of the minimum desirable LPG fuel tank size of 60 to 65 litre 3 0 capacity. Thirdly the rear seat in many such vehicles folds forwards so that the tank is then most inconveniently placed being relatively in the middle of the available room.

The tank instead of being transversely positioned could be longitudinaly 3 5 positioned, however that does not alleviate the difficulty satisfactorily, because it still does extend some way transversely into the available space, especially because the wheel arches extend some way into the rear space of the vehicle.

It has therefore been recognised that it is desirable to fasten the LPG fuel tank 3 beneath the floor space of the vehicle, and that practice is beginning to emerge in the conversion industry. The difficulty with such a practice is that there is limited room beneath the floor space and the ground supporting surface of the vehicle. The existing petrol tank is placed in the that space, and generally in vehicles the configuration is such that a cylindrical fuel container of the size required for Liquid Petroleum Gas cannot easily be fitted in that space, and certainly not together with the existing fuel tank. In some such arrangements the existing fuel tank is reduced in size and modified to allow for the LPG container to be fitted. The fuel tank is in rear wheel drive vehicles positioned directly behind the rear axle, so the LPG tank is fitted behind the petrol tank.

A further problem is that LPG fuel tanks when mounted so as to be exposed to the ground supporting surface is exposed to stresses imparted by reason of debris such as rocks being thrown up and striking the outside surface of he tank. This has far more relevance to LPG tanks because LPG is stored at quite high pressures, and an impact can have dire consequences. It has become a safety requirement to enclose LPG fuel tanks mounted below the vehicle in a housing. This further limits the space available for mounting a petrol tank beneath a vehicle, because the extra housing generally increases the room required for such fitting.

It is an object of the present invention to provide a means of conversion of a vehicle from a petrol driven to an LPG and Petrol driven vehicle or providing a fuel storage arrangement for making a vehicle a petrol and LPG driven which will obviate or minimize any one of the foregoing disadvantages in a simple yet effective manner or at least provide the public with a useful choice.

In a broad form this invention could be said to reside in a fuel storage arrangement for a vehicle of the type having a rear axle means, said arrangement comprising an external housing supported on a vehicle chassis, and depending from beneath a floor level thereof, a cylindrical Liquid Petroleum Gas storage container supported within the external housing adjacent to the rear axle of the vehicle, a petrol storage tank fitted within the external housing and positioned rearwards of the Liquid Petroleum Gas Storage container, a base of the external housing extending generally in line but spaced above a virtual plane, said virtual plane extending between the lower rear end of the vehicle, and the lowermost level of rear wheels of the vehicle, when in their highest position.

The recognition that LPG gas tank can be placed forwards, in place of it being positioned to rear, and that the tank arrangement can be extended towards the virtual plane between the lowermost rear end of the vehicle and a lowermost portion of the rear wheels when in their fully raised position, together with the use of a single housing to encase both the LPG and the Petrol tank enables a larger LPG tank to be used, and for a more space 1 0 effective petrol/LPG tank arrangement.

In an alternate broad form the invention might also be said to reside in a method of fitting a fuel storage arrangement to a vehicle comprising the steps of fastening an external housing to the vehicle chassis beneath the floor so 1 5 that external housing extending downwardly towards but not further than a virtual plane extending between the lower rear end of the vehicle, and the lowermost level of rear wheels of the vehicle when in a fully raised position, fitting a Liquid Petroleum Gas storage container so as to be supported within the external housing and adjacent to the rear axle of the vehicle, fitting a petrol storage tank within the external housing so as to be supported rearwards of the Liquid Petroleum Gas Storage container, For a better understanding of the invention will now be described with .reference to an embodiment which will be described with reference to 25 drawings in which:- FIG. 1 is a somewhat schematic view of part somewhat sectional view 0. through the longitudinal centre of a vehicle showing the layout of the LPG gas tank, the Petrol tank, the external housing in relation to the lowermost rear of the vehicle and the lowermost portion of the wheel when in the raised position, FIG. 2 is part cut-away perspective view from the rear of the inside of vehicle fitted with the arrangement.

Similar reference characters indicate corresponding parts throughout the several views of the drawings.

Dimensions of certain of the parts as shown in the drawings may have been modified and/or exaggerated for the purposes of clarity of illustration.

The illustrated embodiment is of a station wagon and the fuel storage arrangement is particularly shown. The Illustrated embodiment is of a vehicle that has been converted to house both a Liquid Petroleum Gas (LPG) tank 1 as well a petrol tank 2.

The floor 3 of the rear portion of the vehicle generally has a compartment, not shown, for housing a spare tyre together with tools and the like for 1 0 replacement of the tyre. A lid 4 is provided to close the compartment and when closed provides continuity of the floor. This compartment is removed, and in its place is welded an external housing The external housing is of sheet metal fabrication, and includes a sloping 1 5 base 6 and walls extending up from the base to so that when in place the housing defines an enclosed fuel compartment. The uppermost portion of the external housing is flanges such as at 7 and the flange is welded to the metal sheet forming the floor 3 of the rear of the vehicle. The longitudinal edges of the external housing are welded onto rails 8 that strengthen the chassis of the 2 0 vehicle, which enhances the strength of the external housing.

The base is sloped so that is generally follows inside of a virtual plane 9, and is generally in line bust spaced apart from the virtual plane. Virtual plane 9 extends between the lowermost rear portion of the vehicle, which generally S. 2 5 corresponds to the lowermost portion of the rear bumper bar, but might be another portion of the vehicle, however, does not include such additions such as the ball of a towbar, should that lie lower than the remainder of the vehicle.

The forward portion of the virtual plane 9 is defined by a line drawn between a lowermost portion of the wheels 10, when they are in their fully raised 3 0 positions as shown in FIG 1 in broken ;nes. In this embodiment the base of the housing is approximately 40mm spaced apart from the virtual plane.

Generally fuel arrangements have not followed such a virtual plane, but rather have had a lowermost portion following the floor of'the vehicle. By using the 3 5 virtual plane as a reference, greater volume can be provided for whilst maintaining the safety of the arrangement, the risk being that uneven ground impacts on the lowermost portion of the fuel arrangement. This is especially so where an LPG gas tank of substantial volume is desired, because of the rather inflexibility of the shape of such tanks. Such tanks are available only in cylindrical form having hemispherical end portions, and are shaped in that way because the LPG is stored under pressure.

The LPG tank is fitted through the existing opening to the compartment in the rear of the vehicle, and is clamped into place by metal straps 11 fastened to cross-member 12 which cross member is fastened to sides of the external housing, or alternatively to rails 8.

The petrol tank 2 is formed to fit in the remaining space is positioned within the 1 0 external housing, and held into place by straps 14, which straps are fastened between cross member 12 and the base of the external housing. The petrol tank is fabricated from sheet metal and welded together. However it may be preferred to have the petrol tank moulded from a suitable plastics, which advantage could only be obtained by reason of the provision of the external 5 housing, which would protect the plastics from damage caused by projectiles thrown up from the travelling surface.

One advantage of containing both fuel tanks within the housing is that whilst it is mandatory to have an external housing around the outside of the LPG gas 2 0 tank, the extra room needed to surround the LPG gas tank separately including the outlet and inlet control portion 15 is far greater than where the two tanks are housed together.

It is found that with a vehicle of the type sold under the name of Holden 2 5 Commodore and in the configuration of a station wagon, that an LPG gas tank of approximately 75 litre capacity can be fitted together with a Petrol tank of approximately 55 litres capacity, and that the floor of the rear portion of the station wagon need not be cut, other than to remove the existing petrol tank and the rear wheel compartment. It may be that by manufacture with tighter 3 0 tolerances that the volume of the petrol tank could be-further increased.

The remainder of the conversion process is not described in this specification, and can be completed in any number of alternative and approved methods.

3 5 It is to be understood that whilst a station wagon has been illustrated, the arrangement might be positioned on other configurations vehicle configurations.

This embodiment thus allows for a petrol tank of substantial capacity to be provided to give a useful petrol capacity as well as a LPG tank of substantial capacity to be provided, with the option of a substantially normal range of travel on either fuel.

*o e *o*°o oo

Claims

1. A fuel storage arrangement for a vehicle of the type having a rear axle means, said arrangement comprising an external housing supported on a vehicle chassis, and depending from beneath a floor level thereof, a cylindrical Liquid Petroleum Gas storage container supported within the external housing adjacent to the rear axle of the vehicle, a petrol storage tank fitted within the external housing and positioned rearwards of the Liquid Petroleum Gas Storage container, a base of the external housing extending generally in line but spaced above a virtual plane, said virtual plane extending between the lower rear end of the vehicle, and the lowermost level of rear wheels of the vehicle, when in their highest position.

2. A fuel storage arrangement as in claim 1 wherein the LPG tank has a capacity of greater than 60 litres, and the Petrol tank has a capacity of greater than 50 litres.

3. A fuel storage arrangement as in either claim 1 or 2 wherein the external housing fully encloses the LPG tank and the petrol tank and is fastened to rails of the chassis of the vehicle. o r Dated this 25th day of March 1992 NEIL STANLEY BOWLEY MICHAEL ALLAN PAGE By their Patent Attorneys, COLLISON CO. e o e• ooeee oo co 9 ABSTRACT A fuel storage arrangement for a vehicle of the type having a rear axle means, include an external housing depending from the vehicle chassis and a base of the external housing extends generally in line but spaced apart from a virtual plane, the virtual plane extending between the lower rear end of the vehicle, and the lowermost level of rear wheels of the vehicle, when in their highest position. A cylindrical Liquid Petroleum Gas storage container is supported within the external housing adjacent to the rear axle of the vehicle and a petrol 1 0 storage tank fitted within the external housing and positioned rearwards of the Liquid Petroleum Gas Storage container. C C C e ac** r *ee L *o