GB2344088A

GB2344088A - Endless-track conversion for a wheeled vehicle

Info

Publication number: GB2344088A
Application number: GB9927763A
Authority: GB
Inventors: Richard Larrington
Original assignee: Richard Larrington Ltd
Current assignee: Richard Larrington Ltd
Priority date: 1998-11-27
Filing date: 1999-11-25
Publication date: 2000-05-31
Also published as: GB9927763D0; GB9825977D0

Abstract

A wheeled vehicle, such as a trailer, is converted to a tracked vehicle by the replacement of one or more wheels on each side by a respective endless-track unit. As shown, an endless-track assembly has a main track-engaging wheel 9 mounted on the wheel hub of one of the original wheels, a main frame 7 which is supported by an attachment to the hub of another wheel and a further, smaller, main wheel 8 which may be adjustable to adjust the tension in the track 15. Further wheels/rollers 12, 14 guide the track 15.

Description

VEHICLE CONVERSION METHODS AND APPARATUS This invention is concerned with the conversion of the mode of operation of a vehicle from its originally manufactured form/state to a modifie fonny'state with the object of improving the utilisation of the vehicle as compared with its originally manufactured form/state.

Wheeled vehicles such as trailers towed by tractor etc, are commonly used in connection with the wide range of activities carried out in connection with farming and other spheres of usage.

In particular, with farming in all of its various aspects there is an extremely wide spread use of two and four wheeled trailers and two wheeled implements that are intended to be towed by a towing vehicle such as a tractor.

For example, in the case of many trailers it is a conventional practice for the trailers to have tired wheels that are relatively narrow in axial width and are thus more than satisfactory when the terrain over which the trailer is moved presents a firm surface. Such firm surfaces can take many forms such as a dry field, lanes having a relatively even surfaces and so forth.

However, in circumstances in which the terrain is wet, soft or is deeply pitted/rutted by reason of wheel tracks, animal tracks etc., the conventionally provided wheels tend to sink and become bogged down, become difficult to rotate thereby rendering further movement of the trailer very difficult It will be appreciated that the effects of adverse conditions can be greatly dependent upon the load required to be transported by the trailer. In other words the fact that the wheels can become bogged down can greatly restrict or otherwise influence the nature, weight and/or the size of a load a vehicle can carry before becoming unmanageable.

It is an object of the present invention to modify a wheeled vehicle such that its operational characteristics under adverse conditions are improved.

Broadly, according to a first aspect of the invention the wheels of a towed vehicle are replaced by an endless tracked assemblies/units.

Broadly, according to a further aspect of the invention there is provided a method of modifying the structure of a vehicle involving replacing non-steerable road/terrain running wheel assemblies thereof with an endless tracked assemblies/units.

A second aspect of the invention provides an endless tracked assembly/unit adapted for post manufacturing attachment to a vehicle in place of road/terrain running wheels of the vehicle.

Conveniently the assembly is adapted for mounting to a road/terrain running wheel an axle of the vehicle as a replacement for the removed wheel in such manner that the wheel and endless track assembly are operationally interchangeable.

Preferably, the endless track assembly is retainable upon the vehicle axle by a wheel hub assembly initially provided for retaining the replaced wheel on the axle.

In a preferred construction the endless track assembly includes a main body for mounting leading and trailing main drive wheels for an endless track, and wherein at a location intermediate the leading and trailing drive wheels there is provided a mounting for enabling the assembly to be connected to a selected wheel axle of a vehicle to which the endless track assembly is to be mounted.

Conveniently the main drive wheels are positionally adjustable so as to enable tensioning of the track to achieve an optimum performance.

In accordance with aparticular aspect of the invention the road/terrain running wheels of a wheeled vehicle are removed and the wheel hubs along each side thereof are utilised as the hubs for one of the main drive wheels of an endless track assembly.

In a preferred arrangement the endless tracks are formed by endless tracks which were initially designed and intended for use as traction producing tracks for prime mover vehicles but which are no longer capable of producing a requisite degree of traction for such vehicles but which remain suitable for load carrying trailed vehicles. In practice, it has been found that by utilising on a second user basis such endless track constructions the overall cost of a track assembly 6 can be significantly reduced by reason of the economic costs of a first use track and a second use track.

For a better understanding of the invention and to show how to carry the same into effect reference will now be made to the accompanying drawings in which: Figure 1 illustrates a trailer which was originally a two wheeled trailer fitted with endless track assemblies or units according to the invention; Figure 2, is a schematic side view to an enlarged scale of an endless track assembly or unit adapted for post trailer manufacture attachment to the trailer ; and Figure 3 is an axially cross section of the lower part of an endless tracked assembly/unit of Figure 2 Referring now to the Figure 1 a four wheeled trailer 1 shown therein includes a chassis 2 upon which is mounted a trailer body 3. In the Figure the body 3 is shown as an open framework. The trailer shown is of the tiltable type (this being indicated by the incline representation of the trailer body 3A) for the purposes of discharging a load.

The normally provided road/terrain running wheels (not shown) are carried upon a wheel's axle assembly 4 which latter is securely mounted to the underside of the of the chassis 2 in such manner that the ends 5 of the axle project outwardly to provide the actual hubs of xvheel mounting lengths of the axle assembly. As will appreciated the interconnection between the axle assembly and the chassis may be effected by means of a direct attachment or by using springing arrangements (not shown) After removal of the originally provided four wheels an endless track assembly/unit 6 is mounted to each side of the trailer.

Briefly the track assembly 6 incorporates a main body construction'frame 7 that mounts two main drive wheels 8,9 for the endless tracks 10 that for a first arrangement can comprise a series of relatively pivotable tread elements (the latter can be separate tread providing elements pivoted to each other or tread providing elements carried upon a continuous flexible belt arrangement preferably having a textile weave) for engaging with the terrain over which the vehicle is required to move.

In a specific preferred arrangement the endless tracks 10 are formed by endless tracks that were initially designed and intended for use as traction producing tracks for prime mover vehicles but which are no longer capah) e of producing a requisite degree of traction for such vehicles but which remain suitable for load carrying trailed vehicles. In practice, it has been found that by utilising on a second user basis such endless track constructions the overall cost ouf a track assembly 6 can be significantly reduced by reason of the economic costs of a first use track and a second use track.

The main drive wheels 8 and 9 are of different diameters.

The smaller drive wheel 8 is so mounted to the main body 7 as to be relatively displaceable relative to the larger drive wheel 9 to enable the tensioning of the track to attain an optimum performance. In practice, the smaller diameter main wheel 8 is in advance of the larger diameter wheel 9 when the assembly is mounted to the vehicle. This arrangement effectively raises the leading part I 1 of the track above ground level thereby facilitating movement of the track over bumpy ground or the like.

At the upper part of the assembly intermediate of the two main drive wheels there is provided a pair of track support rollers/wheels 12 that are so positioned as to prevent the upper run 13 of the track from sagging between the two main drive wheels.

At the lower part of the body structure there is provided a series of further rollers/wheels 14 that so co-operate with the track as to define the actual path of the lower run 15 of the track. These rollers/wheels 14 can be positionally settable in the vertical sense and can be capable of a predetermined amount of vertical resiliently loaded movement to accommodate running stresses and forces.

These upper and lower rollers can be made of a suitably hard rubber At the central position along the length of the main body frame/structure there is provided means 16 for enabling the assembly to be mounted to the leading axle of the trailer.

For example, this mounting means can include a mounting plate 17 that is securable to the fixed part of the associated trailer axlc structurc.

The main drive wheel 9 is rotatably mounted to the rear axle 18 of the trailer and is mounted thereto by way of a bearing assembly 19 It will be appreciated that the dimensions of the assembly body will be chosen so as to enable the mounting of the assembly to the front and rear axles of the trailer.

Whilst the above description has been concerned with the mounting of the track assemblies/units to towed or trailed four wheeled vehicles, suitably dimensioned assemblies/units could be mounted to two wheeled vehicles.

In this latter case the mounting would convenienlly be centrally of the assembly/unit main body and could be able relatively to float with respect to the trailer chassis or be prevented from such floating.

Claims

CLAIMS 1. A method of modifying the road/terrain capability of as vehicle as initially constructed including the operation of replacing road/terrain running wheel assemblies thereof with endless tracked assemblies ! units.
2. A method as claimed in claim 1, and including the steps of removing the wheel hubs from an axle for mounting selected non steerable road/terrain running wheels, removing and replacing the initially provided road running/terrain running wheels from the axle with an endless tracked road/terrain running assembly and the previously removed hubs are replaced to retain the assembly in operational place on the vehicle.
3. An endless tracked assembly/unit adapted for post manufacturing attachment to a vehicle in place of road/terrain running wheels of the vehicle..
4. An endless track assembly as claimed in claim 3, wherein the assembly is adapted for mounting to a road/terrain running wheel an axle of the vehicle as a replacement for the removed wheel in such manner that the wheel and endless track assembly are operationally interchangeable.
5. An endless track assembly, as claimed in claim 3 or 4 wherein the endless track assembly is retainable upon the vehicle axle hy a wheel hub assembly initially provided for retaining the replaced wheel on the axle.
6. An endless track assembly including a main body for mounting leading and trailing main drive wheels for an endless track, and wherein at a location intermediate the leading and trailing drive wheels there is provided a mounting for enabling the assembly to be connected to a selected wheel axle of a vehicle to which the endless track assembly is to be mounted.
7. An endless track assembly, as claimed in claim 6, and wherein the main drive wheels are positionally ajustable so as to enable tensioning of the track to achieve optimum performance.
8. An endless track assembly as claimed in claim 6 or 7, and wherein the main drive wheels are of different diameters, and wherein the smaller diameter wheel when the assembly is mounted to a vehicle is positioned in advance of the larger diameter wheel when the assembly is mounted to a vehicle axle, the arrangement being such as effectively to raise the leading part of the track above ground level thereby facilitating movement of the tack over uneven ground, terrain.
9. An endless tack assembly as claimed in claim 4,5,6,7 or 8, and wherein upper track support rollslrollers are provided intermediate the main wheels for supporting the upper track part of the endless track, the upper track support rolls/rollers being positioned in such position as to prevent sagging of the upper run of the track between the main drive wheels.
10. An endless track assembly as claimed in claim 9, and wherein a further track positioning rolls/rollers are provided on the assembly frame, in such positions as to define the lower run of the track, and wherein these further rolls/rollers are positionally adjustable in the direction transverse to the direction of the lower run to set the actual path of the lower run of the endless track.
I 1. An endless track assembly as claimed in claim 10, and wherein the second rolls/rollers are capable of a predetermined amount of resilient displacement in said transverse direction to accommodate running stresses and forces.
12. An endless track assembly as claimed in any one of claims 4 to 11, and in which the endless tracks are formed by endless tracks initially intended for traction of à vehicle but which are no longer capable of producing a requisite degree of traction but which remain suitable for load carrying trailed vehicles.
13. An endless track assembly as claimed in any one of claims 4 to 12, and wherein when the vehicle to which it is to be fitted has twin axles trailer the dimensions of the assembly are selected such that the larger diameter main drive wheel is mounted to rear axle of the vehicle and the smaller diameter wheel is mounted to the leading axle of the vehicle.
14. An endless track assembly, constructed and arranged to operate substantially as hereinbefore described with reference to the accompanying drawings.
15. A vehicle when fitted with endless track assemblies as claimed in any one of claims 3 to 14.