WO1993000275A1

WO1993000275A1 - Load-carrying containers

Info

Publication number: WO1993000275A1
Application number: PCT/AU1992/000310
Authority: WO
Inventors: Warren Graham Fairweather
Original assignee: A.S.T. Pty. Ltd.; Clouch Engineering Ltd.
Priority date: 1991-06-25
Filing date: 1992-06-25
Publication date: 1993-01-07

Abstract

A container system for transporting sensitive equipment comprises a box-like container (4) mounted by air bags (10, 12) within a frame (2). The frame (2) supporting the container (4) is loaded onto a vehicle and the air bags form a suspension which isolates the container from shock loading and vibration. The inflation of the air bags can be controlled to set the height of the container within the frame. A set of detachable legs (20) can be coupled to the container and frame and controlled inflation and deflation of the air bags can generate vertical displacement between the container and frame which can be used to enable the container and frame to climb up and down the legs. This facility can be used to effect loading and unloading of the container and frame onto a vehicle.

Description

LOAD-CARRYING CONTAINERS

The present invention relates to load-carrying containers adapted for transportation on a truck or trailer and more particularly, but not exclusively, to a container designed for carrying sensitive equipment such as sensitive electronic or computer equipment.

For military applications, sensitive electronic and computer equipment may be incorporated into a container for transportation to a remote, off-road, location where the equipment is to be operated. In effect the container forms a portable building or shelter in which the equipment is operated at the remote location. Equipment of this type will sometimes need to be transported over rough terrain and extreme care must be exercised to prevent damage to the equipment during transportation. Even transportation along sealed roads requires care to ensure that damage does not take place through vibration. To avoid damage during transport, the equipment is sometimes specially adapted to withstand vibration . This is known as "ruggedising" the equipment and adds significantly to the cost of the equipment. Similar problems may arise in the transportation of certain general (non-military) telecommunications equipment, radio and television broadcasting equipment, and computer equipment.

Another problem which exists involves the unloading of containers from the vehicle at a remote location. The container including the equipment may weigh up to several tons. Loading and unloading can easily be effected by means of a crane or forklift but often this f acility will not be available at the remote location. There have been proposed jacking systems for use with the container at a remote location and which permit the container to be unloaded from, and reloaded onto, the vehicle, but previously proposed jacking systems have proved very cumbersome to operate. It will be appreciated that the problems which arise in unloading and loading containers from vehicles at remote locations are not confined to containers for sensitive electronic equipment.

According to one aspect of the present invention there is provided a container system for transportation of sensitive equipment comprising a container for carrying the equipment, support means for supporting the container from a surface of a vehicle, and a pneumatic suspension system interposed between the support means and the container such that the container is carried from the support means via the pneumatic suspension system whereby to isolate the container from shock loading and vibration, the container and support means being movable as a unit onto and from the vehicle.

Advantageously, the pneumatic suspension system comprises air bags, and control means to control the inflation of the air bags. The control means may be associated with height sensors to retain the container at a predetermined height relative to the support means.

Preferably, the support means comprises an open frame within which the container is supported.

Preferably, the air bags comprise groups of upper and lower air bags to support the container from above and from below.

According to another aspect of the invention there is provided a container system comprising a container, support means for supporting the container from a surface, fluid operated means interposed between the container and the support means for causing controlled vertical movement between the support means and the container, a guide structure adapted to extend upwardly from the ground, and means carried by the container and support means and engageable selectively with the guide structure to effect a climbing movement of the container system up and down the guide structure consequent on relative vertical movement between the container and support means.

Advantageously, the fluid operated support means comprises air bags which can be selectively inflated and deflated to effect relative vertical movement between the container and support means, and the guide structure comprises a series of legs detachably connectable to the container and support means.

Still further according to the invention there is provided a set of detachable legs for forming the guide structure for use in the above container system, each leg being of ladder-like form with rungs which cooperate with means carried by the support means and container to effect climbing movement up or down the leg, the styles of the ladder defining guide tracks to guide the support means and container during such movement.

An embodiment of the invention will now be described by way of example only with reference to the accompanying drawings in which:-

Figure 1 is a perspective view of a container system in accordance with the invention in conjunction with jacking legs therefor;

Figure 2 is a fragmentary end view of the container system and jacking legs; and

Figure 3 is a plan view of the container system.

The container system of the preferred embodiment is primarily designed for use in transporting sensitive equipment by providing a pneumatic suspension for the container itself. The pneumatic suspension is also combined with a jacking system which facilitates unloading and loading of the container system from and onto a truck or trailer at a remote location.

The container system comprises an open rectangular frame 2 within which a box-like container 4 itself is mounted by a pneumatic suspension system. The frame 2 comprises rectangular end frames 6 at each end interconnected by longitudinal frame members 8. The suspension system comprises upper and lower sets of air bags 10, 12 adjacent the corner portions of the two end frames 6 and extending between the end frames and the upper and lower walls of the container 4 to support the container 4 from the frame 2 and to provide controlled movement of the container 4 upwardly and downwardly relative to the frame 12. The air bags 10, 12 are of flexible bellows-type construction. The lower air bags 12 have a greater cross-sectional area than the upper air bags 10 in order to provide a differential effect between the upper and lower sets of air bags for reasons to be described hereinafter.

Lateral and longitudinal stability of the container 4 within the frame 2 can be achieved by incorporating radius arms or stabilising means between the frame 2 and the container 4. However a lateral and longitudinal stabilising function can be achieved by means of the air bags themselves by mounting each air bag so that its longitudinal axis is directed inwardly towards the container both in a vertical plane (for example as viewed in Figure 2) and in a horizontal plane (for example as viewed in Figure 3). In this way the bags can absorb not only the vertical ride forces but also lateral and longitudinal forces arising from cornering, acceleration and braking. Although the inclined mounting of the air bags should provide adequate lateral and longitudinal stability for most applications, it is of course possible to increase the stabilising action by incorporating additional means such as radius arms. It is, of course, possible for the air bags to be mounted with their longitudinal axes directed vertically, in which case longitudinal and lateral stabilising means would normally be required for the container within the frame. The air bags 10, 12 are supplied with pressurised air from a suitable source via a control system. Normally the vehicle on which the container system is carried will have an air brake system and the pressurised air for the air bags can be taken from that. Alternatively, a separate air compressor can be incorporated in the container system. The air is supplied to the air bags through valves which regulate the pressure to ensure that the container 4 is supported at a predetermined height above the base of the frame 2. For this purpose, height control sensors can be interposed between the container 4 and the frame 2 to control the air supply to the air bags to maintain a prescribed height.

It will be appreciated that the load carried by the lower bags 12 will be significantly greater than that carried by the upper bags 10. The larger cross- sectional area of the lower bags 10 enables this differential loading to be achieved. However in an alternative configuration, the upper and lower bags can be of the same cross-sectional area, with differential pressures being applied between the upper and lower air bags using valves which control the pressure applied to the upper and lower sets of air bags.

In use, the supporting frame 2 will rest on the tray of a truck or trailer, and the pneumatic suspension system between the container 4 and the supporting frame 2 will carry substantially the entire weight of the container and contents and isolate the container 4 from potentially damaging vibrations and shock loading arising during transportation. This enables sensitive equipment to be transported at relatively high speed on the vehicle without the need to modify the basic suspension of the vehicle itself and without the need to "ruggedise" the equipment.

The frame 2 incorporates conventional lifting points or lifting eyes to permit the container system to be loaded onto and/or from the vehicle by a forklift truck or crane if these are available at the location. The pneumatic suspension system incorporated between the frame 2 and the container 4 can be used also to provide controlled upwards and downwards movement between the container 4 and the frame 2 and this effect can be utilised in conjunction with a jacking system to permit jacking of the container system onto and off the vehicle.

The jacking system comprises four legs 20 each of ladder-like form. The styles 22 of each ladder 20 are of channel form, with the channels being open outwardly to define guide tracks for guide rollers (not shown) associated with the frame 2 and container 4. Each ladder 20 has at its lower end an adjustable mounting 24 which enables the ladder 20 to be set at a desired height above the ground. In use, the ladders are located at the opposite sides of the frame 2 adjacent each of the four vertical corners of the frame 2. For each ladder 20, the frame 2 has upper and lower sets of laterally extending brackets 26, 28, and the container has a lower set of brackets 30, each set of brackets 26, 28, 30 having guide rollers which engage in the outwardly directed channels of the ladder styles to enable the rollers to be guided for vertical movement along the ladder. The brackets may also carry guide rollers 32 which span the outer edges of the two styles 22 of the ladder to run along the outer edges. Either the guide rollers 32 or the rollers within the open channel can be omitted. The brackets 26, 28, 30 may be removably attached to the frame and container, respectively. The lateral extension of the brackets is such that the ladders 20 at the opposite sides of the frame 2 will be spaced by a distance greater than the width of the bed of the truck or trailer so that the ladders 20 can contact the ground at each side of the truck or trailer.

Each of the lower brackets 28, 30 carries a spring pawl 34 in a position to cooperate with the individual rungs of the ladder. Each pawl 34 is retractable against the spring action by means of a separate pneumatic cylinder (not shown) associated with the respective pawls. By sequential extension and retraction of the respective pawls 34 and inflation and deflation of the air bags 10, 12, the frame 2 and container 4 can be made to climb up and down die ladders 20 as will now be described in greater detail.

In a situation where the frame 2 with the container 4 is being supported on the bed of the truck or trailer and it is desired to unload the frame and container, the ladders 20 are positioned at each side of the truck or trailer and are engaged with the brackets 26, 28, 30 carrying the rollers. The container 4 is then raised within the frame 2 either by inflating the lower air bags 12 or by deflating the upper air bags 10 (if the lower bags are already inflated) through a distance such that the pawls 34 associated with the container 4 engage with the next upper rung of the ladders 20 under the spring action which causes the pawls 34 to extend. The lower air bags 12 are then deflated and the upper air bags 10 inflated to lift the frame 2 relative to the container 4 through a distance at which the pawls 34 associated with the frame 2 engage with the next upper rung under the spring action of the pawls 34. This process continues until the frame 2 and container 4 are at a sufficient height above the bed of the truck or trailer to enable the truck or trailer to be withdrawn from underneath the frame. The container 4 and frame 2 can then be lowered to the ground in sequential steps which cause the container 4 and frame 2 to climb down the rungs of the ladders 20. The lowering action is accomplished by activating the pneumatic cyhnders to withdraw the pawls 34 associated with the container 4 and then deflating the lower air bags 12 so that the container 4 moves downwardly relative to the frame 2 to a position at which the pawls 34 associated with the container 4 engage in the next lower rung under the spring action of the pawls. The pawls 34 associated with the frame 2 are then withdrawn and the lower air bags 12 inflated in order to push the frame 2 downwardly relative to the container 4 to a position at which the frame pawls 34 engage with their spring action with the next lower rung. These steps are repeated until the frame 2 is resting on the ground.

Loading of the frame 2 and container 4 onto the truck or trailer is accomplished by raising the frame 2 and container 4 from the ground by climbing up the rungs of the ladders 20 as described at the outset, to a height at which the bed of the truck or trailer can be manoeuvred beneath the raised frame 2 and then lowering the frame 2 and container 4 onto the bed by climbing down the rungs, again as described previously. The correct sequencing of the air supply to inflate and deflate the air bags 10, 12 and to retract the pawls 34 can be achieved by manually operated valves, with suitable safety valves including shuttle valves, to ensure that the pawls associated with the container 4 cannot be withdrawn at the same time as the pawls associated with the frame 2. Automatic control of the sequencing can be obtained by an automatic pneumatic valving system or an electronic control system for the valves.

The embodiments have been described byway of example only and modifications are possible within the scope of the invention.

Claims

CLAIMS:-

1. A container system for transportation of sensitive equipment comprising a container for carrying the equipment, support means for supporting the container from a surface of a vehicle, and a pneumatic suspension system interposed between the support means and the container such that the container is carried from the support means via the pneumatic suspension system whereby to isolate the container from shock loading and vibration, the container and support means being movable as a unit onto and from the vehicle.

2. A container system according to claim 1, wherein the pneumatic suspension system comprises air bags, and control means to control the inflation of the air bags.

3. A container system according to claim 2, wherein the support means comprises a frame within which the container is supported.

4. A container system according to claim 2 or claim 3, wherein the air bags comprise groups of upper and lower air bags to support the container from the support means from above and from below.

5. A container system according to claim 3 or claim 4, wherein the container is of box-like form and there is a group of upper air bags between upper corner portions of the container and the support means, and a group of lower air bags between lower comer portions of the container and the support means.

6. A container system according to claim 4 or claim 5, wherein the total cross-sectional area of the group of lower air bags is greater than that of the group of upper air bags.

7. A container system according to any one of claims 2 to 6, wherein at least some of the air bags have an axis of operation inclined to provide a lateral and longitudinal stabilising force for the container relative to the support means.

8. A container system according to any one of claims 2 to 7, wherein the control means comprises sensor means interposed between the container and support means such that the container is retained at a predetermined height relative to the support means.

9. A container system according to any one of claims 2 to 8, wherein the control means is operable to effect controlled vertical movement between the container and the support means, said container system further comprising a guide structure adapted to extend upwardly from the ground, and means carried by the container and support means and engageable selectively with the guide structure to effect a climbing movement of the container system up and down the guide structure consequent on relative vertical movement between the container and support means.

10. A container system according to claim 9, wherein the control means is operable to selectively inflate and deflate the air bags to effect relative vertical movement between the container and support means, and the guide structure comprises a series of legs detachably connectable to the container and support means.

11. A container system according to claim 10, wherein each leg is of ladder¬ like form with rungs which co-operate with means carried by the support means and container to effect climbing movement up or down the leg, the styles of the ladder defining guide tracks to guide the support means and container during such movement.