FIELD OF THE INVENTION

This invention relates to machinery and, in particular, to track driven equipment. The invention extends to a method for facilitating movement of such equipment and to an accessory for facilitating movement of track driven equipment.

BACKGROUND TO THE INVENTION

Drilling rigs, bulldozers, military vehicles, tractors, and the like, are all examples of well known track driven equipment. They normally include at least one endless tread-type track which is a continuous loop of rubber or metal plates, arranged around driving wheels. Such a track provides improved traction over soft or rough ground, compared to vehicles having wheels only.

Besides having the above mentioned maneuverability advantage, track driven equipment are normally bulky and slow moving, thereby hindering easy transportation. They are therefore usually transported on public roads by means of trucks equipped with a low bed; or on railways by loading them on railway carriages.

When a truck with a low bed facility is not available onto which the track driven equipment can be loaded for transport from point A to point B, work operations are unnecessarily halted until such truck arrives. In many of these cases, one finds, for example, a track driven drilling rig crawling along, either on a gravel public road or alongside a surfaced public road, all by itself and slowly on its way to a desired destination.

This is not ideal and not only wastes valuable operational time, but also presents dangerous conditions for other road users. Therefore, track driven equipment adapted to address the above problems is believed to hold great benefit.

SUMMARY OF THE INVENTION

In accordance with the invention there is provided an accessory for facilitating movement of track driven equipment having a track forming a continuous loop around wheels mounted to a chassis of said equipment, the accessory comprising a rolling assembly operatively mounted to the track driven equipment and being displaceable between a movable position in which the rolling assembly is in rolling contact with the ground, and a stationary position in which the track is in contact with the ground and the rolling assembly raised relative to the ground.

There is also provided for the rolling assembly to comprise displacement means operable to move said rolling assembly between the stationary position and the movable position. Preferably, the displacement means comprises hydraulic cylinders or mechanical jacks.

There is further provided for the rolling assembly to comprise a frame and axle arrangement with at least one wheel operatively mounted to the frame and axle arrangement. Typically, the frame and axle arrangement comprises double wheels mounted on a single axle. Alternatively, the frame and axle arrangement comprises single or double wheels mounted on a double axle.

Additionally, there is provided for the frame and axle arrangement to comprise a suspension that utilizes a solid axle, blade spring packs, air bags or a walking beam. ln accordance with a further aspect of the invention there is provided for track driven equipment comprising: a chassis; an engine; a transmission; a track forming a continuous loop around wheels mounted to the chassis, the track being adapted to be driven by the wheels; and an accessory for facilitating movement of the track driven equipment, the accessory including a rolling assembly operatively mounted to the chassis and being displaceable between a movable position in which the assembly is in rolling contact with the ground, and a stationary position in which the track is in contact with the ground with the rolling assembly raised relative to the ground.

The track driven equipment is adapted to take the form of a drilling rig, bulldozer, armoured vehicle, military vehicle, tractor or the like.

There is also provided for the track driven equipment to further include attachment means operable to permit attachment of said track driven equipment to a towing vehicle.

There is further provided for the rolling assembly of the track driven equipment to comprise a frame and axle arrangement with at least one wheel operatively mounted to the frame and axle arrangement. Typically, the frame and axle arrangement comprises double wheels mounted on a single axle. Alternatively, the frame and axle arrangement comprises single or double wheels mounted on a double axle.

Additionally, there is provided for the frame and axle arrangement of the track driven equipment to comprise a suspension that utilizes a solid axle, blade spring packs, air bags or a walking beam.

The track driven equipment is also adapted so that the rolling assembly can be moved between the stationary position and the movable position by means of displacement means. Preferably, the displacement means comprises hydraulic cylinders or mechanical jacks.

Further, there is provided for the track driven equipment to include repositioning means mounted to the chassis for selectively changing the position of the track relative to the ground from an operative position, in which the track is in contact with the ground; and an inoperative position, in which the track is raised relative to the ground. Preferably, the repositioning means comprises hydraulic cylinders or mechanical jacks.

In accordance with yet a further aspect of the invention there is provided a method for facilitating movement of track driven equipment as described hereinbefore, the method including: changing the position of the track to an inoperative position by way of the repositioning means; moving the rolling assembly by way of the displacement means from the stationary position to the movable position; attaching the attachment means to a towing vehicle; and towing the track driven equipment to a desired location.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the invention are now described, by way of example, with reference to the accompanying non-limiting diagrammatic drawings. In the drawings: shows a side elevation of a track driven drilling rig having an accessory, for facilitating movement of the drilling rig, in a stationary position according to a first embodiment of the invention; shows a side elevation of the drilling rig of Figure 1 , with an endless track in an inoperative position; shows a side elevation of the drilling rig of Figure 1 , with a rolling assembly of the accessory being moved to a movable position; shows a side elevation of the drilling rig of Figure 1 , attached to a tow- truck and with a rolling assembly of the accesory being in a movable position; shows a side elevation of the accessory for facilitating movement of the drilling rig of Figure 1 ; shows a side elevation of an accessory for facilitating movement of track driven equipment according to an alternative embodiment of the invention; shows a side elevation of an accessory for facilitating movement of track driven equipment according to a further alternative embodiment of the invention; and

Figure 8 shows a side elevation of the accessory of Figure 7 in a stationary position.

DETAILED DESCRIPTION OF THE DRAWINGS

In the drawings, like numerals generally indicate like components, unless otherwise indicated. Referring to Figures 1 to 5, reference numeral 10 generally refers to an accessory for facilitating movement of track driven equipment in accordance with a first embodiment of the invention. In particular, reference numerals 10.1 and 10.2, as depicted in Figure 6 and Figures 7 to 8 respectively, refer to further accessories in accordance with the invention. Accessories, 10.1 and 10.2 provide alternative means for facilitating movement of track driven equipment.

In Figures 1 to 5, the accessory 10 is shown in a stationary position, but mounted to an endless track driven drilling rig 50. Although a drilling rig is shown, it will be appreciated that the accessory 10 could also be used with alternative track driven equipment such as bulldozers, armoured vehicles, military vehicles, tractors and the like.

As shown in Figures 1 to 5, the accessory 10 includes a rolling assembly 12 which is mounted to the drilling rig 50. The rolling assembly 12 can be displaced from a movable position in which same is in rolling contact with the ground to a stationary position in which an endless track 13 of drilling rig 50 is in contact with the ground while the rolling assembly 12 is raised relative to the ground. Displacement from the stationary position, as indicated in Figure 1 , to the movable position, as indicated in Figures 3 and 4, occurs via displacement means 14.

The track driven drilling rig 50.2 of Figures 7 and 8 illustrate the operation of displacement means 14.2 in the form of a hydraulic cylinder 16.2 while the drilling rig 50 shown in Figures 1 to 5 and the drilling rig 50.1 shown in Figure 6 all employ a typical telescopic mechanical jack 16 to selectively lower or raise the respective rolling assemblies 12 and 12.1 through an angle of about 85 ^° . The hydraulic cylinder 16.2 typically, but not necessarily, consists of a cylinder barrel, in which a piston connected to a piston rod moves back and forth. Hydraulic pressure acts on the piston to do linear work and effect motion. The respective rolling assemblies 12 and 12.1 , typically includes a frame-and-axle 18, and at least one wheel 20 operatively mounted to the frame-and-axle 18. As shown in Figure 6, the rolling assembly 12.1 has only a single wheel 20.1 mounted on a frame- and-axle 18.1 as opposed to the double axle bogie shown in Figures 1 to 5. Although further alternatives are not shown, it will be appreciated that any alternatively combination of a wheel and frame-and-axle arrangement also falls within the spirit and scope of the invention. Moreover, the rolling assembly 12,12.1 may also have a suspension that utilizes a solid axle, blade spring packs, air bags or a walking beam. According to a further aspect of the invention a track driven drilling rig 50 is provided as shown in Figures 1 to 5. The rig 50 has a chassis 52, a transmission connected to an engine (not shown), a track 13, and a series of track mounted shoes 54 arranged in a continuous loop around wheels (not shown) mounted to the chassis 52. The series of shoes 54 is typically driven by the wheels (not shown). The rig 50 also includes an accessory 20 for facilitating movement of the rig 50, the accessory 20 including a rolling assembly 12 operatively mounted to the chassis 52 and being displaceable between a movable position in which the assembly 12 is in rolling contact with the ground, and a stationary position in which the series of shoes 54 is in contact with the ground while the rolling assembly 20 is raised relative to the ground.

Although a drilling rig 50 is shown, it is envisaged that in accordance with this aspect of the invention other track driven equipment such as, for example, drilling rigs, bulldozers, armoured vehicles, and the like may also utilize this accessory 10. The rig 50, or any of the vehicles mentioned hereinbefore, also has attachment means 56 in the form of a tow bar or hitch for attachment to a towing vehicle such as a horse of a truck or a tractor.

The drilling rig 50 of Figures 1 to 5 and the rig 50.1 of Figure 6 as well as the rig 50.2 of Figures 7 and 8 are all respectively equipped with accessory 10, 10.1 , and 10.2 for facilitating movement of the rigs in accordance with the invention.

Additionally, there is provided for the drilling rig 50, 50.1 , 50.2 or any other track driven equipment equipped with the accessory 10, 10.1 , or 10.2 to have repositioning means 80 for selectively changing the position of the track 13 and the series of track mounted shoes 54, relative to the ground. Preferably, the position is changed between an operative position in which the series of shoes 54 is in contact with the ground (as shown in Figure 1 ), and an inoperative position (as shown in Figure 4) in which the series of shoes is raised relative to the ground.

It will also be appreciated that the repositioning means 80 may also be either hydraulic cylinders or mechanical jacks or any other means capable of raising and lowering the track 13 relative to the ground. In fact, both the displacement means 14 and the repositioning means 80 may utilize the same hydraulic cylinders or mechanical jack. In use an operator (not shown) of the rig 50, 50.1 , 50.2 or the operator of any other track driven equipment equipped with the accessory 10, 10.1 , 10.2 may halt normal operations with the rig 50, 50.1 , 50.2 or with said other equipment to prepare for a long haul. The operator then changes the position of the track 13 to an inoperative position by way of the repositioning means 80 which lifts the track 13 and the series of shoes 54 from the ground. The operator then moves the rolling assembly 12 of the accessory 10 by way of the displacement means 14 from the stationary position to the movable position through the 85 ^° angle. Thereafter, the operator attaches the attachment means 56 on the frame-and-axle arrangement 18 to a towing vehicle 82 as shown in Figure 4. The towing vehicle 82 is then ready to relocate the rig 50, 50.1 , 50.2 or said other track driven equipment equipped with the accessory 10, 10.1 , 10.2 to a desired location in quick time.

The applicant believes that the accessory 10, 10.1 , 10.2 or rig 50, 50.1 , 50.2 of the present invention, at least in part, addresses shortcomings in conventional track driven equipment in that expensive track undercarriage wear is eliminated and uncomplicated relocation is made possible.

While preferred embodiments of the invention are shown and described, it will be understood that it is not intended to limit the extent of the invention, but rather it is intended to cover all modifications and alternate methods, including: methods, for manufacturing the accessory 10, 10.1 , 10.2 or rig 50, 50.1 , 50.2 and components thereof, falling within the spirit and the scope of the invention.