The invention has commercial application in covering goods stacks at any location which require protection in the form of sheeting. Where goods are manufactured, transported or stored in bulk, they may require protection from atmospheric and other conditions. In particular, such protection is advisable for goods stacked outside prior to shipping, for example to the customer. The invention has particular application in sheeting stacks of bagged goods such as bagged fertiliser in conjunction with use of a fork lift truck.

In the past, sheeting of large goods stacks has been a manual operation. The worker was thus required to climb onto the stack to position the sheets in each case and also to rope down the sheets and attach them together where more than one sheet was required to cover the stack.

Such manual sheeting and unsheeting carries inherent safety risks for the worker and is also time consuming.

Sheet weight for such applications may be of the order of 0.5 kg per metre2 and the sheets are thus difficult to handle, especially in windy or rainy conditions. There is an added difficulty in sheet handling in cold conditions, where patches of ice may form.

Manual sheet handling may also lead to sheet damage or damage to the goods in the stacks. For example, if the worker climbs onto the top of a goods stack and also uses his weight to manoeuvre the sheet, this may damage the goods packaging at the top layer.

Forklift trucks have been used as an alternative to purely manual handling to unsheet stacks by threading the fork attachment through sheet portions or between ropes holding the sheets together. However, this uncontrolled use of forklift trucks increases the risk of damaging the sheets.

Sheeting mechanisms are known from several documents such as JO 7125542, which describes a device for sheeting good on a truck. However such devices are generally only suitable to cover the contents of a vehicle. A sheeting mechanism for luggage on a forklift truck is further known, for example from JO 8143291. Such mechanisms are not suitable for sheeting goods stacks.

It is therefore an object of the present invention to overcome or mitigate some or all of the disadvantages of the prior art.

It is a further object of the present invention to provide a mobile sheeting and/or unsheeting device which is cost effective and safe.

It is a further object of the present invention to provide a mobile sheeting and/or unsheeting device that can be mounted to a vehicle for transport between goods stacks.

According to a first aspect of the present invention there is provided a mobile sheeting and/or unsheeting device for an object or goods, comprising a boom having means for attachment to a sheet, a boom support and boom displacement means to translate the boom between first and second positions relative to the object or goods, whereby the object or goods are at least partially covered or uncovered.

The present invention allows improved sheeting and/or unsheeting of an object or goods such as a stack of goods in terms of work safety, time taken and goods and sheet handling.

Reference herein to a boom is to an elongate member, which is adapted for translation.

Reference herein to a sheet is to a thin covering member, such as a tarpaulin, a mesh, net or the like, which may be used to protect or contain an object or goods. Preferably the sheet is flexible.

Reference herein to an object is to any large, inaccessible or otherwise unmanageable goods which it is impractical, unsafe or undesirable to cover manually.

Reference herein to goods is to any form of goods, which may be finished or semi-finished products or raw materials. The goods may be packaged or unpackaged.

Goods may be in the form of a goods stack, i. e., a pile of goods in one or more layers provided on a surface, which may be a mobile or a fixed surface or even be formed from a plurality of sub-surfaces, such as pallets. The stack may

further comprise additional members such as support or packaging members apart from the goods.

The boom displacement means may provide any suitable displacement for covering and uncovering a stack of goods. For example the boom displacement means may provide any combination of one or more rotations about any axis or axes, and/or one or more translations in a substantially horizontal or vertical or any other direction in use.

Preferably the boom displacement means provides at least a rotation of the boom. Such a rotation is about any suitable axis. Preferably, the rotation is about an axis substantially parallel to the longitudinal axis of the boom. More preferably the axis is spaced from the longitudinal axis of the boom.

The resultant arc movement may have any suitable angular extent between 1 and 360 ° and is preferably of up to 180°. The arc may be in any preferred plane and is preferably in a vertical or substantially vertical plane to allow the sheet to be deployed over the goods stack.

In one preferred embodiment the boom support comprises a radius arm that rotates to provide rotation of the boom as hereinbefore defined.

The radius arm may extend at any angle to the boom. Preferably, it extends substantially at right angles thereto. More preferably, the boom is connected to the distal end of the radius arm and the length of the radius arm from its rotational axis to the boom determines the basic arc radius. The radius arm rotational axis is preferably substantially horizontal in use to provide a substantially vertical arc as hereinbefore defined.

The arc movement may form the arc of a circle or, alternatively arc adjustment means may be provided to adjust the boom displacement by increasing and decreasing the arc amplitude. Arc adjustment means allow any necessary adjustment of the boom trajectory, for example, to avoid hazards above or to the sides of the goods stack, to lengthen the arc to fit over larger goods stacks or to keep the boom close to the top of the stack in windy conditions.

Arc adjustment means may be operable separately or together with the other movements of the boom: they may, for example, be automatically activated by the other movements. Preferably the arc adjustment means are operable and controllable separately from the other movements of the boom. This allows adaptation of the arc to specific circumstances.

The arc adjustment means may comprise any suitable physical arrangement. In one preferred embodiment the arc adjustment means as hereinbefore defined comprise at least length adjustment means for the radius arm. In this case, the direction of arc adjustment is dependent on the angular position of the arm.

Additionally or alternatively, arc adjustment means may comprise shift means which transport the entire device in a direction such as to lengthen or shorten the arc with respect to the goods stack. Such shift means act in a substantially horizontal direction.

Preferably, the boom displacement means comprises both boom translation means and boom rotation means. The boom translation means may allow translation in any direction of the boom. Preferably, boom translation means allow raising and/or lowering of the boom, for example between sheet attachment/detachment positions and arc start/finish positions and/or at the top

of the arc to counter wind effects. More preferably, boom translation means allow substantially vertical translation Boom translation means may translate the boom alone, the boom and radius arm or the entire device. For example, the radius arm may be mounted directly or via device mounting to any means which allows its vertical movement. It may be adjustably mounted to a mast or other substantially vertical shaft or vertically moving component in use. The mobile device as hereinbefore defined may comprise such a mast or component or a mast/component may be provided separately.

In a preferred embodiment, the boom displacement means comprises both boom translation means and boom rotation means. More preferably, the boom displacement means further comprises arc adjustment means. Any suitable alternative construction may be envisaged which provides these displacements for the boom. For example, a cam track, preferably with adjustable sections, a robot arm or any other accommodation of mechanical parts may be envisaged.

Boom displacement means as hereinbefore defined may be provided with control means to co-ordinate and actuate the individual movements which allow the boom to translate between first and second positions relative to the object or goods.

Preferably the boom displacement control means comprise hydraulic or pneumatic actuators and a control system therefore. The control system may further control other parts, such as further hydraulic or pneumatic actuators.

The boom may remain in the substantially same orientation with respect to the horizontal in use or may be provided with boom tilt means to alter this

orientation during use. Such boom tilt means are particularly useful for countering the effects of wind when manoeuvring sheets.

Preferably, the device as hereinbefore defined comprises boom tilt means such that the distal boom end may be translated up or down with respect to the proximal boom end. With this feature, the distal end may be moved downwards to prevent wind from travelling under the sheet at its far end and exerting possibly dangerous forces on the device.

Any suitable boom tilt means may be envisaged, in particular, the mast/component as hereinbefore defined may be rotatable about a horizontal axis such that the entire device tilts or, the mounting of the device, radius arm or boom itself may be adjustable.

The device as hereinbefore defined may be freestanding or may be mounted to a fixed or mobile structure or surface for support. Preferably, the device comprises device mounting means which allow it to be mounted to a support.

More preferably, the radius arm is rotatably mounted to the device mounting means.

In one preferred embodiment, the device mounting means allow attachment to a mobile support such as a vehicle in use. Any suitable vehicle such as a moveable frame, truck, van, wagon, forklift truck or train or modification thereof may be envisaged.

Preferably the device mounting means allows attachment directly to the body, or via a mast or other component, of a vehicle in use. More preferably, the device mounting means allow attachment directly to a modified fork lift truck,

hereinafter FLT, of which the lifting mechanism is useful, optionally of which the forks are removed to enable manoeuvring close to the object or goods.

The device mounting means may allow mounting to any part of the vehicle such as a front, back, side, or top thereof ; preferably the front of the vehicle for ease of viewing of the boom.

The device may have any orientation with respect to the vehicle to which it is mounted. For example, the boom may be parallel, at right angles or at any other angle to the longitudinal axis of the vehicle in use. Preferably, the boom is substantially parallel to the longitudinal axis in use. This allows easier manoeuvrability of the vehicle between goods stacks. The boom is therefore preferably substantially horizontal in use. Preferably the radius arm axis is substantially parallel to the longitudinal axis of the vehicle In another preferred embodiment the boom is substantially perpendicular to the longitudinal axis of the vehicle in use. In this case or in general, the vehicle may be destabilised in particular when using a boom which projects to one side of the vehicle to a distance greater than at least half the vehicle width.

In a preferred embodiment the vehicle or an attachment provides one or more stabilising feet as known in the construction industry in general. These may be permanent or detachable.

The movement of the vehicle between stacks transports the device. Vehicle movement may also contribute to arc adjustment during sheeting and act as an additional or only shift means; alternatively the boom displacement means of the device may be sufficient for displacement of the sheet.

The boom may remain in substantially the same position or be (re) movable when in and out of use and during transport and storage. For example, the device may comprise boom retraction means such that the boom has an in use unretracted and deployed and an out of use retracted position. Such boom retraction means may include, for example, one or more telescopic sections, rotation means allowing boom rotation into a stored position, boom folding means, translation means or any other suitable retraction means. Alternatively the boom may be removable out of use such that the stored boom position is slightly above the horizontal low position used when the sheet is attached and therefore there are no retraction means. This is particularly useful if the boom is of excessive length for transport or storage.

In one preferred embodiment the boom retraction means comprise boom rotation means for rotation of the radius arm from its lowest to its highest angular position. This avoids any contact of the boom with uneven ground or low obstacles in travel.

Any suitable sheet attachment means may be provided on the boom or alternatively the attachment means may be provided on the sheet such as hooks, warps, lines, a track or recess to receive a profiled sheet end or the like.

Preferably, sheet attachment means in the form of at least two hooks are provided on the boom Attachment means may be directly mounted on the boom or indirectly via an adjustable mounting, for example via rams which are hydraulically operated.

Sheet winding means may also be provided on the boom such that it can rotate to wind up a sheet along its extent. Such winding means allow continuous rotation of the boom with respect to its axis on the radius arm.

Any cross section of boom may be envisaged which could be suitable for the process. Preferably a hollow cross-section boom is provided for its strength to weight ratio. In our preferred embodiments the boom is circular or square in cross section.

The device may be provided with further safety features to enhance its operability. For example, one or more cameras, lights and audible or other alarms may be provided to aid the driver of the vehicle and alert anyone in the area of the device.

Preferably an audible alarm is provided which is louder at the distal end of the boom and quieter in the vehicle cab.

Preferably at least one camera is provided to view the length of the boom.

More preferably the camera is mounted to the distal end of the radius arm.

Preferably, the device control system is connected to the vehicle control system to prevent movement of or limit the speed of the vehicle when the device is in use.

In a further aspect of the present invention there is provided the use of a device as hereinbefore defined for sheeting and/or unsheeting stacks of goods.

In a further aspect of the present invention there is provided a method for sheeting and/or unsheeting stacks of goods comprising the steps of attaching a sheet to a boom and displacing the boom such that the sheet travels between positions in which it covers more or less of the stack.

Preferably the boom displacement includes rotation. Such a rotation is about any suitable axis. Preferably, the rotation is about an axis substantially parallel

to the longitudinal axis of the boom. More preferably the axis is spaced from the longitudinal axis of the boom.

The resultant arc movement may have any suitable angular extent between 1 and 360 ° and is preferably of up to 180°. The arc may be in any preferred plane and is preferably in a vertical plane, to allow the sheet to be deployed over the goods stack.

The arc movement may form the arc of a circle or, alternatively arc adjustment means may be actuated to adjust the boom displacement by increasing and decreasing the arc amplitude.

Arc adjustment may be separate or together with the other movements of the boom: it may, for example, be automatically activated by the other movements. Preferably the arc adjustment is operable and controllable separately from the other movements of the boom. This allows adaptation of the arc to specific circumstances.

Preferably, the boom displacement comprises both boom translation and boom rotation. The boom translation may be in any direction. Preferably, boom translation allows raising and/or lowering of the boom, preferably between sheet attachment/detachment positions and arc start/finish positions. More preferably, boom translation is substantially vertical translation Boom translation may translate the boom alone, the boom and radius arm or the entire device

In a preferred embodiment, the boom displacement comprises boom translation, boom rotation and arc adjustment. Boom displacement as hereinbefore defined may be controlled to co-ordinate and actuate the individual movements which allow the boom to cover more or less of the stack in any given circumstances.

The boom may remain in the substantially same orientation with respect to the horizontal in use or may be tilted to alter this orientation during use. Such tilting is particularly useful for countering the effects of wind when manoeuvring sheets.

Further characteristics of the method correspond to details of the device as hereinbefore defined.

In a further aspect of the present invention there is provided a kit of parts forming the device as hereinbefore defined comprising a boom, radius arm and optionally comprising preferred characteristics of the device as hereinbefore defined.

In a further aspect of the present invention there is provided a control system for a device as hereinbefore defined. The control system may be linked to a vehicle control system.

In a further aspect of the present invention there is provided a device as hereinbefore defined in combination with a vehicle, preferably a forklift truck.

Further advantages of the invention will be apparent from the foregoing.

The invention is now illustrated in non-limiting manner with reference to the following figures and examples in which: Figure 1 shows a side view of a device according to the present invention mounted to a forklift truck.

Figure 2 is a vertical cross section of a radius arm according to the present invention in two different positions.

Figure 3 is a three dimensional sketch of one embodiment of a device according to the present invention.

Figure 4 is a side view of a goods stack and boom arc.

Figure 1 shows mobile device (1) at a low position on mast (6) of modified (forkless) fork lift truck (FLT) (5) and also shows the device at the highest position. The cab of the FLT can rise so that the driver can monitor the boom and sheet. The device comprises boom (2), which is aligned with the longitudinal axis of the FLT, radius arm (3) and mounting means (4).

The device can be raised up mast (6) or lifted up by a fork lift (not shown), from a low position into a high position.

The device is in a stored position during travel, with radius arm (3) in a vertical position to hold the boom safely above ground. On arrival at to the goods stack the FLT is driven into position facing the stack with the boom centrally over the stack. In general, the boom must be rotated and lowered into a narrow aisle, between adjacent stacks for this.

Once the FLT is in position, the radius arm (3) rotates a quarter turn to its lowest position for manual sheet attachment. The device is then raised.

Rotation of the radius arm 180 degrees carries the sheet across the stack.

Figure 2 shows the lift mechanism of the FLT of Figure 1 in detail, illustrating a section of the possible arc (8) of the boom carrying a sheet across a stack.

Radius arm (3) is shown in a horizontal (lowest) position H, in a non-extended vertical position V for comparison and in the actual extended positions HE & VE for the arc.

Figure 2 also illustrates shift, which is visible from the changed axis of the radius arm in its two positions. Shift may be achieved using the side shift feature of FLTs. Stabilising feet (one shown) (7) serve to stabilise, in this case for a sideways destabilising shift of 5.6 m (horizontal), thereby overcoming any overturning moment.

The radius arm completes its 180 degree rotation to cover the stack and the device is then lowered to detach the sheet. Naturally, the same movements are suitable for uncovering stacks.

Figure 3 illustrates a simple preferred embodiment of the device for mounting to the mast of an FLT. Device mounting means (4) are shown as a rotator on which the radius arm (3) is rotatably mounted. Length adjustment means (9) of radius arm (3) are shown as a hydraulic or pneumatic actuator. An attachment point (10) for a camera and/or light and/or siren is shown.

Figure 4 shows the arc (8) of a boom (2) covering a stack (11) of around 4 m in height. The sheet is attached to the boom at A. The device is raised to point B. The arc from B to E is caused by the combined effects of rotating

radius arm (3), adjusting its length and lowering the device. The flat arc top is useful to combat wind effects.

Further advantages of the invention will be apparent from the foregoing.

REFERENCE NUMERALS 1. Mobile Device 2. Boom 3. Radius arm 4. Device mounting means 5. Fork lift truck 6. Mast of fork lift truck 7. Stabilising foot 8. Arc 9. Adjustment means for radius arm 10. Camera attachment 11. Stack