GB2290759A

GB2290759A - Coal carrying vehicle

Info

Publication number: GB2290759A
Application number: GB9413037A
Authority: GB
Inventors: Alan Henry Bilton
Original assignee: HAY ROYDS MINING Ltd
Current assignee: HAY ROYDS MINING Ltd
Priority date: 1994-06-29
Filing date: 1994-06-29
Publication date: 1996-01-10
Also published as: GB9413037D0

Abstract

The vehicle 10 has a front end 10a on which is a load container 11 typically containing coal. At the rear end 10b is a cab 12 in which sits an operative. The cab 12 and an engine (not shown) act as a counter balance to the load 11. The vehicle is provided with three axles 13, 14 and 15, each axle having a ground contacting wheel 16 at each end thereof. Axles 13 and 15 are in a common plane below which is located axle 14. The load 11 tips the vehicle forwards so that the wheels 16 of the first and second axles 13 and 14 are in contact with the ground, represented by 17, and these wheels drive and steer the vehicle in a conventional skid steer technique. When empty the wheels 16 of the second and third axles 14 and 15 are in contact with the ground. <IMAGE>

Description

LOAD CARRYING VEHICLE The present invention relates to a load carrying vehicle and is concerned particularly, although not exclusively with a load carrying vehicle which is steerable using a skid-steer technique.

Skid-steer vehicles are commonly used to transport heavy loads such as earth and are typically used in mines for transporting coal from a coal face. A known skidsteer vehicle has two axles, each with two ground wheels, a load container at the front of the vehicle and a rear mounted engine which acts a counter balance to the load.

Typically, neither pair of wheels is steerable. Drive is supplied to both axles and to steer the vehicle the wheels on one side of the vehicle are locked while the wheels on the other side of the vehicle are driven. For example to turn right, the right side wheels are locked and the left side wheels are driven.

A counter balance which may typically be the engine itself and/or the driver's cab is place rearward of the rear axle whilst the load is placed forward of the front axle. The counter balance is needed to prevent the vehicle from tipping forwards, i.e. pivoting about the front axle, when the vehicle is loaded. However, the counter balance if too large may cause tipping backwards, i.e. pivoting about the rear axle, when the vehicle is not loaded. This problem is particularly serious if the two axles are relatively close together, which is desirable in a skid steer vehicle if the power required to turn the vehicle is not to be too great, i.e. the further apart the axles are, the more power is required to steer the vehicle.

In an effort to reduce the problem of tipping which is particularly likely when bumps or inclines are encountered by the vehicle, it has been suggested to place extra weight over the centre of the vehicle to act as a counter balance to the load when loaded, and to act as a counter balance to the engine when the vehicle is unloaded. However, this has the disadvantage that it adds to the overall weight of the vehicle and thus more power is needed to turn the vehicle. Also there is a greater wear on the tyres of the vehicle and a greater wear on the ground surface when turning due to the extra friction caused by the greater weight of the vehicle.

Accordingly, it is an object of the present invention to provide a vehicle for carrying a load in which at least some of the above problems are at least partly lessened.

According to a first aspect of the present invention there is provided a vehicle for carrying a load, the vehicle comprising first, second and third axles, each axle having at least one ground wheel, characterised in that the vehicle is moveable between a first position in which, in use, the wheels of the first and second axles are in contact with the ground and the or each wheel of the third axle is above ground, and a second position in which, in use, the wheels of the second and third axles are in contact with the ground and the or each wheel of the first axle is above ground.

The first, second and third axles may be arranged in use such that they do not lie in a common plane.

The wheels may be of substantially the same diameter or, alternatively, at least one of the wheels may be of a different diameter.

Preferably, the vehicle comprises first, second and third axles in substantially parallel configuration, the first and third axles being the outer axles with respect to the vehicle and may be in a common plane, the second axle being located between the first and third axles and may be arranged in use to be below the common plane of the first and third axles.

Preferably, the vehicle is arranged in use to be steered by inhibiting the turning of at least some of the ground wheels on a first side of the vehicle whilst driving at least some of the ground wheels on a second, opposed side of the vehicle.

The vehicle may be of the type known as a skid steer vehicle.

Preferably, the vehicle is arranged in use to receive a load at a first end thereof.

The vehicle may be arranged in use to carry a counter balance weight at a second, opposed end thereof.

The vehicle may be provided with a load container at the first end thereof. The vehicle may be provided with an engine located at the second end thereof. Preferably, the first end of the vehicle comprises a front end.

Preferably, the second end of the vehicle comprises a rear end.

Preferably, the vehicle is provided with means to support an operative at the rear end of the vehicle; the means to support the operative may comprise a cab or seat.

The vehicle may be provided with two ground wheels on each of the three axles. Each of the wheels of the vehicle may be arranged to be driven by the engine.

Preferably, the first axle is located in use towards the front of the vehicle, the third axle being located towards the rear of the vehicle and the second axle being located substantially midway along the vehicle, between the first and third axles.

Preferably, the vehicle is arranged in use to transport a load in a mine.

According to a second aspect of the present invention there is provided a method of constructing a vehicle for carrying a load, the method comprising mounting three axles on the vehicle, each axle being arranged in use to have at least one ground wheel, wherein the three axles are not in a common plane.

The method may comprise a method of constructing a vehicle according to any statement herein.

The method may include any combination of the features or limitations referred to herein.

The invention may be carried into practice in various ways but an embodiment will now be described by way of example only with reference to the accompanying diagrammatic drawings in which: Figure 1 shows schematically a vehicle according to an embodiment of the present invention in a loaded configuration, and Figure 2 shows schematically the vehicle of Figure 1 in an unloaded configuration.

Referring to Figure 1 this shows a vehicle generally at 10, such as for transporting coal in an underground mine.

At the front end 10a of the vehicle is a load container 11 which typically in use contains coal. At the rear end 10b is a cab 12 in which an operative (not shown) sits in use. The cab 12 and an engine (not shown) act as a counter balance to the load 11.

The vehicle is provided with three axles 13, 14 and 15, each axle having a ground contacting wheel 16 at each end thereof. Axles 13 and 15 are in a common plane below which is located axle 14. In a configuration shown in Figure 1, the load 11 tips the vehicle forwards so that the wheels 16 of the first and second axles 13 and 14 are in contact with the ground, represented by 17, and these wheels drive and steer the vehicle in a conventional skid steer technique.

Figure 2 shows the configuration of the vehicle 10 when the load 11 has been removed. In this configuration the counter balance weight 12 tips the vehicle rearwardly and the wheels 16 of the second and third axles 14 and 15 are in contact with the ground. Since all six wheels are driven the vehicle may be controlled in the skid steer conventional technique.

Effectively the vehicle is able to pivot about the wheels 16 of axle 14. In the loaded configuration the vehicle is unlikely to tip further forwards about the wheels of axle 13 since the counter balance weight 12 is relatively far from axle 13 and therefore the moment about wheels 16 of axle 13 caused by the downward force of weight 12 is relatively large.

Conversely, in the unloaded configuration, the vehicle is unlikely to tip further backwards about the wheels 16 of axle 15 since the load container is relatively far from the axle 15 and therefore the moment about wheels 16 of axle 15 caused by the downward force of the container is relatively large.

This design allows the overall weight of the vehicle 10 to be kept to a minimum with the choice of counter balance weight being arranged according to the intended load. This reduces wear on the tyres and on the ground surface when turning and also reduces the amount of power required to turn the vehicle. Since whichever two pairs of wheels are in contact with the ground are relatively close together, the power required to turn the vehicle need be no greater than that of a conventional two axle machine.

The invention provides a stable machine for moving a load, the machine being of relatively low weight.

It will be understood by those skilled in the art that various modifications may be made to the invention without departing from its scope. For example, the embodiment shown is for use in a mine, but the invention could equally be employed in a surface vehicle with suitable modifications where necessary.

Claims

CLAIMS:

1. A vehicle for carrying a load, the vehicle comprising first, second and third axles, each axle having at least one ground wheel, characterised in that the vehicle is moveable between a first position in which, in use, the wheels of the first and second axles are in contact with the ground and the or each wheel of the third axle is above ground, and a second position in which, in use, the wheels of the second and third axles are in contact with the ground and the or each wheel of the first axle is above ground.

2. A vehicle according to claim 1, wherein the first, second and third axles are arranged, in use, such that they do not lie ion a common plane.

3. A vehicle according to claim 1 or claim 2, wherein the wheels are of substantially the same diameter.

4. A vehicle according to claim 1 or claim 2, wherein at least one of the wheels is of a different diameter to at least one other of the wheels.

5. A vehicle according to any of claims 1 to 4, wherein the vehicle comprises first, second and third axles in substantially parallel configuration, the first and third axles being the outer axles with respect to the vehicle and being in a common plane, the second axle being located between the first and third axles and being arranged, in use, to be below the common plane of the first and third axles.

6. A vehicle according to any of claims 1 to 5, wherein the vehicle is arranged, in use, to be steered by inhibiting the turning of at least some of the ground wheels on a first side of the vehicle whilst driving at least some of the ground wheels on a second, opposed side of the vehicle.

7. A vehicle according to any of claims 1 to 6, wherein the vehicle is of the type known as a skid steer vehicle.

8. A vehicle according to any of claims 1 to 7, wherein the vehicle is arranged, in use, to receive a load at a first end thereof.

9. A vehicle according to claim 8, wherein the vehicle is arranged, in use, to carry a counter balance weight at a second, opposed end thereof.

10. A vehicle according to claim 8, wherein the vehicle is provided with a load container at the first end thereof.

11. A vehicle according to claim 9, wherein the vehicle is provided with an engine located at the second end of thereof.

12. A vehicle according to claim 10, wherein the first end of the vehicle comprising a front end.

13. A vehicle according to claim 11, wherein the second end of the vehicle comprises a rear end.

14. A vehicle according to claim 13, wherein the vehicle is provided with means to support an operative at the rear end of the vehicle.

15. A vehicle according to claim 14, wherein the means to support the operative comprises a cab or seat.

16. A vehicle according to any of claims 1 to 15, wherein the vehicle is provided with two ground wheels on each of the three axles.

17. A vehicle according to claim 16, wherein each of the wheels of the vehicle are arranged to be driven by the engine.

18. A vehicle according to any of claims 1 to 17, wherein the first axle is located in use towards the front of the vehicle, the third axle being located towards the rear of the vehicle and the second axle being located substantially midway along the vehicle, between the first and third axles.

19. A vehicle according to any of claims 1 to 18, wherein the vehicle is arranged, in use, to transport a load in a mine.

20. A vehicle for carrying a load, the vehicle being substantially as herein described with reference to the accompanying drawings.

21. A method of constructing a vehicle for carrying a load, the method comprising mounting three axles on the vehicle, each axle being arranged, in use, to have at least one ground wheel, wherein the three axles are not in a common plane.

22. A method according to claim 21, comprising a method of constructing a vehicle according to any of claims 1 to 20.

23. A method of constructing a vehicle for carrying a load, the method being substantially as herein described with reference to the accompanying drawings.