Transportable units

The present invention relates generally to lifting of transportable units such as metal shipping containers, accommodation units, trailers and the like (hereafter referred to as 'transportable units').

Due to their purpose, transportable units often need to be moved from one location to another. For example, they need to be loaded onto ships, lorries or other means of transportation, or placed in situ on sites for the purpose of loading/unloading contents. It is common, therefore, to need to lift such transportable units in order to place them elsewhere.

Traditionally, transportable units are lifted by connecting the unit to a hoisting device such as a crane, winch or other hoisting means. This is typically achieved by hooking, or otherwise securing, chains or lines to the unit. Lifting eyes are typically provided, welded or otherwise secured to the unit, usually at the uppermost corners of such transportable units for this purpose. Once the lines are attached to the lifting eyes at the uppermost corners of the unit, the hoist is able to lift the unit.

However, the arrangement described requires personnel to scale the unit or position a ladder and manually secure the lines via the apertures at the top corners. This poses a safety risk as there is a danger of the personnel falling from the container or ladder.

Thus, it is an object of the invention to provide a means of lifting a transportable unit, such as a shipping container, accommodation unit, trailer or the like, without the need for personnel to scale the unit, thus eliminating the risk of injury posed by falling. A further object of the invention is to provide a lifting arrangement which can be fitted retrospectively to a pre-existing unit with minimal expense and effort.

Thus in accordance with the present invention, there is provided a transportable unit having a lifting aid arrangement comprising a plurality of substantially upwardly extending guide elements conjoined to the unit; a moveable lifter element being configured to travel along

respective guide elements, and stop means positioned towards the elevated end of respective guide elements such that respective lifter elements are inhibited by the stop means from further upwards travel.

In a preferred embodiment, guide elements are located at two or more positions on a transportable unit. Preferably, a guide element is located near each corner of the transportable unit, the number and position of the guide elements used being calculated so as to facilitate lifting and provide maximum stability of the transportable unit during the lifting process. It is also preferred that each guide element is an elongate element which is configured to accommodate a lifter element. The lifter element is beneficially held captive with respect to the guide element but still able to move along the guide element. The profile of the guide element for example can be shaped to ensure that this effect is realised.

In a preferred embodiment, the guide element may take the form of a channel, conduit or shaft. The profile of the channel may be of a substantially rectangular form, one side of the channel being provided with inwardly projecting limbs. However, a person skilled in the art will appreciate that guide elements of different profiles may be used. For example, the guide element may comprise a track or rail. Alternatively a hydraulic ram or chain drive may comprise the guide element. The guide element may therefore be provided with drive means to drive the lifter upwardly.

Each guide element is configured to accommodate a lifter element. The lifter element is able to travel along the guide element. The movement of the lifter element may be a rolling, sliding or gliding motion. In an arrangement wherein the lifter element rolls along the guide element, one or more wheels may be attached to the body of the lifter element. In such an embodiment, the wheels may be connected to the body of the moveable member and may be arranged and configured to interact with grooved or recessed portions provided on, within or by the guide element.

In a preferred embodiment, each lifter element provides a means for connecting the lifter element to a hoist, crane or other lifting device. In such an embodiment, the connection means may be provided by a lifting eye aperture of the lifter element such that a hook or

other device may be inserted to conjoin the lifter element to the hoisting device. In one embodiment of the invention, the lifting eye is provided within a raised portion of the lifter element such that the raised portion projects away from (i.e. perpendicular to) the body of the lifter element, and extends beyond one end of the body of the lifter element. Thus, when the lifter element is in an upright orientation the aperture is positioned such that the hook and chain (or other hoist connecting means) stand proud of the guide element and do not rub or grate upon the guide element or the transportable unit.

Prior to lifting the transportable unit, each lifter element rests within its respective guide element. As each guide element is positioned in a substantially vertical orientation, gravity causes the lifter element to rest at or towards the bottom of the guide.

In a preferred embodiment, the resting position of the lifter element within the guide is at or close to ground level. It is desired that the hook and chain (or other lifting gear/ hoist connecting means) is connected to each lifter element while in this position, thus avoiding the need for personnel to scale the unit in order to connect the unit to the hoisting device, and thus reducing the risk of injury.

As the lifting gear exerts an upwards force, the lifter elements (being connected to the lifting gear) are pulled upwards (i.e. towards the top of the transportable unit) along their respective guide elements.

In accordance with the present invention, the movement of each movable element is arrested by an obstructive stop means located at, or towards, the top of its respective guide element. The obstructive stop means prevents the lifter element from travelling further along, or beyond the end of, the guide element. In a preferred embodiment, the obstructive stop means may be an end plate or cap, although a person skilled in the art will understand that other types and arrangements of obstructive means may be provided to prevent further travel of the lifter element. Also, in one embodiment the obstructive stop means may be attached to the guide element while alternative embodiments may provide the obstructive means as an integral part of the guide element, or as attached to the transportable unit, or as an integral part of the transportable unit.

In a preferred embodiment, the obstructive stop means is configured to enable the lifting eye aperture of the raised portion of the lifter element to protrude above the top edge of the unit so that the lines connecting the moveable unit to the lifting gear do not come into contact with the lifting aid or the unit. This prevents damage which may otherwise be caused to the unit (for example damage to the paintwork). It also facilitates lifting of the unit.

As each lifter element is prevented from travelling further along the guiding element upon reaching the obstructive stop means an upward force is exerted upon the transportable unit which is then lifted.

When the transportable unit has been positioned over the desired destination, it is lowered by the hoisting device until the bottom of the unit makes contact with the ground or other surface. As the lifting gear continues to be lowered, the lifter elements return, under their own weight, to their respective resting positions at or towards the bottom of their respective guide elements. The hoist connecting means may then be disconnected from the lifter elements which are now at or close to ground level. Again, this is achieved without the need to climb upon the container thus eliminating or reducing the risk of injury.

In an embodiment of the invention, the guide elements (and thus the lifter elements which they accommodate) may be fitted retrospectively to an existing unit created to a traditional design. In such an embodiment, the guide elements may be bolted or welded or otherwise secured to the body of the transportable unit. The guide elements may be secured in a permanent or removable fashion. In an alternative embodiment, however, the guide elements may be formed as an integral feature during the manufacture of the unit itself.

In a further embodiment, adjustable legs may be fitted to the bottom end of one or more guide elements for the purpose of levelling the unit when it is placed upon an uneven surface. The leg is therefore beneficially adjustable between a ground engaging configuration and a stowed position. Preferably, in the stowed position the leg is secured

with respect to the guide, preferably the leg moves longitudinally with respect to the guide between the stowed and operational positions.

These and other aspects of the present invention will be apparent from and elucidated with reference to, the embodiment described herein.

According to a further aspect, the invention provides a method of lifting a transportable unit, wherein a lifting force is exerted upon a lifter element, causing said lifter element to travel along a substantially upwardly extending guide element, said guide element being conjoined to said transportable unit, until further upwards travel of the lifter element is prevented by the presence of a stop means for the respective guide element, thereafter the lifting force being applied via the stop means to lift the unit.

An embodiment of the present invention will now be described, by way of example only, and with reference to the accompany drawings, in which:

Figure 1 illustrates a transportable unit in accordance with the present invention.

Figure Ia also shows an alternative embodiment of transportable unit in accordance with the invention.

Figure Ib shows a detailed view of a part of the container of figure Ia.

Figure 2 is a perspective view of a lifter element configured for use in-accordance with the present invention.

Figure 3 shows an alternative perspective view of the lifter element of figure 2.

Figure 4 is a detailed view of the element of figure 3.

Figures 5 to 7 illustrates a side, rear and plan views respectively of the lifter element of figures 2 to 4.

Figure 8 illustrates an embodiment of a guide element configured for use with the present invention.

Figure 9 illustrates the profile of an embodiment of a guide element configured for use with the present invention.

Figure 10 illustrates a guide element configured for use with the present invention, having a lifter element positioned within the guide element and an obstructive stop element for preventing further travel of the lifter element.

Figure 11 shows a guide element configured for use with the present invention and having an adjustable leg for levelling of the unit.

With reference to the above listed Figures, Figure 1 shows a transportable unit (1), such as a shipping container, trailer, accommodation unit or the like, provided with a lifting aid according to the present invention. Guides (2) are conjoined to the unit (1), each guide being, in this embodiment, of channel form and accommodating a lifter element (3) which can be connected to (and disconnected from) a hoisting device such as a crane or winch (not illustrated), typically via a line such as a cable or chain (4). Prior to lifting, the bottom edge (10) of the unit (1) rests on the ground or other surface.

Figure 1 a shows a more detailed view of a transportable unit having a lifting aid according to the present invention. Connection lines (4) to the hoisting device are not shown. The guide channels (2) are shown conjoined to the exterior of the unit (1). As shown most clearly in figure 8, a lifter element (3) is mounted to travel along each guide channel (2) such that the apertured eye (7) for connecting the lifter element (3) to the hoisting device stands proud of an end stop (9) provided at the upper end of the guide channel (2). The end stop (9) prevents the lifter element (3) from travelling further once it has reached the top, or is close to the top, of the guide element (2) and contacts with the end stop (9).

Figure Ib shows a detailed view of an embodiment wherein the guide element (2) is conjoined to the exterior of the unit (1), specifically by being bolted to the unit. The bolts pass through flanges of fixing brackets (17) provided at the upper and lower ends of the guide channels (2). The fixing brackets (17) are shaped and dimensioned to be received in the channels (18) commonly provided running along the top and bottom of containers and accommodation units.

Figure 3 shows an embodiment of a lifter element (3) having wheels (6) for providing a rolling motion along the guide channel (2). The wheels are attached to the body of the lifter element (3). A raised portion (8) projects perpendicularly from the body of the lifter element and extends beyond one end of the body of the lifter element. The apertured lifting eye (7) is positioned within the raised portion (8) beyond the body of the lifter element (3) such that the lifter element may be connected to the hoisting device, and that the hoisting device or connecting line is prevented from grating or rubbing against the unit.

Figures 5, 6 and 7 show side, rear and plan views of the same embodiment of the lifter element (3) respectively.

Figure 4 shows a detailed view of a wheel (6) secured to the body of a lifter element (3) in a preferred embodiment.

As shown most clearly in figures 8 and 9, the guide (2) is generally channel form and shaped and dimensioned such that a respective lifter element (3) may travel freely until it encounters an obstructive end stop (9) positioned at or towards the top of the guide (2). The obstructive end stop (9) features a notch (11) which permits the raised portion (8) of the lifter element (3) to protrude through the obstructive element (9) thus preventing contact between the hoisting device (or connecting lines) and the unit. The channel (2) is shaped to have opposed sidewalls (2a, 2b) spaced by a back wall (2c). An elongate slot (2d) is defined at the front portion of the guide channel by inwardly extending limbs (2e, 2f), leading to terminal portions (2g, 2h) extending toward the back wall (2c). This shape ensures that the lifter element is retained captive with respect to the guide (2) (the wheels 6

being constrained by the limbs (2e, 2d)), but permits the lifter element (3) to move longitudinally along the guide, the element 8 extending transversely through the slot (2d).

The arrangement features an adjustable leg (11) positioned within the guide element for the purpose of levelling the unit if placed upon an uneven surface. The leg is stowed within the channel and can be extended for use.

In use, with the unit resting on the ground surface, the lifter elements (3) are at rest at the bottom of the respective guides (2). When the unit is to be moved, the lifting hooks of the lifting gear are secured through the lifting eyes (7) and the lifting gear raises the lifter elements (3) to travel upwardly along the respective guides(2). Ultimately, the lifter elements engage with the respective end stops (9) and thereafter the lifting force is applied to the unit (1) which is lifted from the ground, the lifting gear taking the weight of the unit. . The procedure is reversed to lower the unit (1). The arrangement provides that the unit (1) can be lifted from a lifting point at the top of the unit (as is conventional) but that attachment to the lifting gear can be made at a point well below the top of the unit. The need to mount the unit or climb ladders is therefore avoided. The guides can be formed integrally with the unit or secured in a retro-fit operation. The connection can be permanent or removable.

It should be noted that the above-mentioned embodiments illustrate rather than limit the invention, and that those skilled in the art will be capable of designing many alternative embodiments without departing from the scope of the invention as defined by the appended claims. In the claims, any reference signs placed in parentheses shall not be construed as limiting the claims. The word "comprising" and "comprises", and the like, does not exclude the presence of elements or steps other than those listed in any claim or the specification as a whole. The singular reference of an element does not exclude the plural reference of such elements and vice-versa. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage.