AU2006201652A1 - Wrapping device - Google Patents

Description

AUSTRALIA

Patents Act 1990 COMPLETE SPECIFICATION STANDARD PATENT Applicant: AMIATA HOLDINGS PTY LTD Invention Title: WRAPPING DEVICE The following statement is a full description of this invention, including the best method of performing it known to us: -2- WRAPPING APPARATUS This invention relates to a wrapping apparatus and, more particularly, to a device that combines a wrapping dispensing spool with an elevating load platform.

In our co-pending patent application 2005201658, we disclose an elevating load platform that is specifically designed to be used with palletised loads. The load platform incorporates a series of springs that ensure that the platform is maintained at an optimal height as it is either loaded or unloaded. This sort of equipment is particularly useful in preventing back injuries to those that have to lift loads from pallets.

In recent years there has been increased use of wrapping devices in which a load on a pallet is wrapped in plastics sheeting under tension that causes the plastics to shrink on the load and thus firmly locates and, at times, encapsulates the load on the pallet. Such devices usually include a mechanism that rotates the load as the plastics sheet is unwound from the spool under tension so that the plastics sheet wraps around the load.

It is these issues that have brought about the present invention.

In accordance with one aspect of the present invention there is provided a wrapping apparatus comprising a wrap dispensing spool adapted to be coupled to an elevating load platform, the spool including a substantially vertically extending shaft adapted to accommodate a roll of wrapping material whereby the roll can axially rotate relative to the spool to facilitate unwrapping of the material, the elevating load platform comprising a turntable supported by a scissor linkage above a base, drive means to rotate the turntable and H:\me1indaf\keep\Speci's\P60603 wrapping apparatus.doc 20/04/06 3 control means to control the rotation of the turntable.

Preferably, the rotation of the roll of material is controlled by an adjustable brake. Preferably a clutch controls rotation of the turntable. The wrap dispensing spool preferably includes a wheeled base adapted to be attached to the load platform.

An embodiment of the present 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 part of a wrapping apparatus; Figure 2 is a perspective view of the part of Figure 1 viewed from the other side; Figure 3 is a perspective view of the part of Figures 1 and 2 in a folding configuration; Figure 4 is an exploded perspective view of the wrapping apparatus constituted by the part of Figure 1 and 2 and a loading platform; Figure 5 is an enlarged perspective view illustrating the join between the two components of Figure 4; Figure 6 is a plan view of the assembled apparatus; Figure 7 is a sectional view of the top of a feeding spool of the apparatus; Figure 8 is a schematic side view showing the drive of a turntable disconnected from an electric motor; Figure 9 is a schematic side view with the motor connected; Figure 10 is a perspective view of part of the drive mechanism for the turntable; Figure 11 is a cross sectional view of part of a wrap spool sheet that forms part of the apparatus; and Figure 12 is a cross sectional view taken along the lines X-X of Figure 11.

H:\melindaf\keep\Speci's\P60603 wrapping apparatus.doc 20/04/06 4 The shrink wrap apparatus 10 illustrated in the accompanying drawings essentially comprises the combination of components shown in Figure 4, namely a shrink wrap dispenser 20 that can be attached to an elevating load platform 100 of the kind described in our co-pending patent application 2005201658, the description of which is incorporated herein by reference.

The wrap dispenser 20 comprises a triangular base platform 21 with a forward end 22 having wheels 23 at each corner and a rearward end 25 that supports a pair of spaced wheels 26. The rear end 25 of the triangular platform 21 supports a mast 30 which, in turn, supports a spool assembly 40 that is displaceable vertically relative to the mast 30 and includes a vertically extending spool 41 that can support a roll 42 of plastics film with the spool 41 having the capacity to be axially rotatable about an adjustable brake 45. The mast 30 is pivotally secured to the base platform 21 so that it can be folded down to a position in which it is parallel to the base platform 21 for storage as shown in Figure 3.

As shown in Figures 11 and 12, the mast 30 comprises a hollow square cross sectioned metal beam 31 that houses a circular PVC pipe 32 that extends down the length of the beam. The pipe 32 in turn accommodates a cylindrical weight 33 that is coupled via a pulley 34 through webbing to the outside of a sleeve 36 that is adapted to be a sliding fit on the exterior of the beam 31. The sleeve 36 comprises a square sectioned steel bracket that supports on its internal surfaces PVC or Teflon M 37 that is held to the interior of the bracket via screws 38. The Teflon M 38 is in sliding contact with the exterior of the beam 31 and allows the sleeve 36 to be a smooth sliding fit about the exterior of the beam. The sleeve 36 has a lug 39 welded to the exterior to which is attached the webbing 35 but also has welded thereto a laterally projecting flange 43 H:\melindaf\keep\Speci's\P60603 wrapping apparatus.doc 20/04/06 5 which in turn supports the spool 41. The underside of the flange has a downwardly projecting leg 44 that contacts the base platform 21 to determine the lowest position of the sleeve 36 and spool 41. As shown in Figures 1 and 2 a handle 46, 47 is secured to each side of the sleeve to extend upwardly parallel to the mast 30. The handle in combination with the weight 33 that is a sliding fit within the mast 30 enables the sleeve 36 and spool 41 to be easily slid up and down the mast 30 so that the roll of plastics film is at the appropriate height.

The spool comprises a fixed vertical shaft 41 with a threaded end 51 supporting a nut 52. A rubber or plastics frusto conical member 53 sits on the lower end of the shaft 41 and a similar frusto conical member 54 sits at the upper end engaged by a handle 55 that is screwed to the threaded end 51. When a roll 42 of plastics film is positioned on the shaft 41, the cylindrical tube 56 on which the film is wound has its opposite ends engaged by the frusto conical members 53, 54 and axial rotation of the roll 42 relative to these members is permissible with the freedom of this motion depending on how the handle has been adjusted to force the inclined surfaces 57, 58 of the cones 53, 54 into the cardboard tube 56 to act as a brake resisting axial rotation. Successful wrapping requires the plastics film to be stretched three fold and thus it is important that the axial rotation of the roll 42 is braked to cause the film to stretch. If the handle is rotated on the threaded end 51 of the shaft, it forces the cones 53, 54 into firmer contact with the roll thus acting as a brake, resisting axial rotation of the roll. If the handle is unscrewed, the reverse happens and the roll becomes free to rotate and to thus reduce the tension on the plastics film.

The mast 30 also supports a control box 60 on its front surface that includes an emergency cut out switch H:\melindaf\keep\Speci s\P60603 wrapping apparatusadoc 20/04/06 6 61. The control box 60 has a lead 62 that can be coupled to a source of mains electricity which in this case would be simple single phase mains electricity. The power from the power box 60 is fed down through the mast 30 and under the platform to terminate in a plug 64 at the front end 22 of the platform 21. When the platform 21 is assembled to an elevating load platform 100, the plug 64 meets with a corresponding socket 101 on the load platform 100 to provide power to the platform which, as will be described later in the specification, is used to cause rotation of a turntable 120.

The elevating platform 100 is substantially the same as the platform described in our co-pending patent application and is thus not described herein in detail.

In essence, the elevating platform 100 comprises a turntable 120 that is supported by a scissor linkage 105 above a base structure 106. A series of coil springs 110 are positioned within the scissor linkage 105 to control the vertical movement of the platform in dependence of the load that it carries. The platform is arranged to rotate about a circular frame 121 that supports rollers 122, 123 spaced around the periphery so the platform operates like a turntable. Figures 6 and 10 illustrate this arrangement. The difference between the elevating load platform 100 of this application and the platform described in our earlier specification concerns a mechanism to drive the turntable 120.

As shown in Figure 10, an electric motor 130 has its output shaft coupled through a gear box 132 to a sprocket 133 that drives a chain 134 that is connected to a sprocket 135 that is mounted on a sprag clutch 136 on an output shaft 137 that is, in turn, coupled to a wheel 140 with a hard rubber exterior 141. The hard rubber exterior 141 of the wheel sits directly underneath the turntable 120 so that rotation of the wheel 140 imparts rotational H:\me1indaf\keep\Speci'S\P60603 wrapping apparatus.doc 20/04/06 7 movement of the turntable on the rollers 122, 123 that are on the support frame 121 shown in Figure 10. The sprag clutch 136 enables connection or disconnection of the drive so that the turntable 120 can be freely rotated by hand if necessary.

This drive is schematically illustrated in Figures 8 and 9. In Figure 8, the turntable 120 is being loaded and is free to rotate because the sprag clutch 136 is shown in a disengaged position. In Figure 9, the sprag clutch 136 is in its engaged position which causes drive from the electric motor 130 to the output sprockets 133, 135 and chain 134 which, in turn, drives the rubber coated wheel 140 to rotate the turntable 120.

As shown with particular reference to Figures 4 and the wrap dispenser 20 is adapted to be coupled to the load platform 100 through the use of a pair of sockets 150, 151 positioned in the load platform 100 that accommodates tapered forks 70, 71 at the front end 22 of the base 21 of the dispenser 20. As the forks are positioned in the sockets, this causes the electrical plug 64 and socket 101 to come into mating contact and a spring loaded latch 75 shown in Figure 5 can be pulled into position thereby securing the two components together and ensuring the electrical connection.

In use, a roll of plastics film 42 is positioned on the dispenser 20 and the load platform 100 is filled with product with the sprag clutch 136 disconnected. This allows the platform to be loaded from one side due to its ability to rotate freely. The sprag clutch 136 is then connected and a length of plastics film is manually wrapped around the product as shown in Figure 6. Before wrapping the plastics around the load the spool 40 is positioned at the correct height by gripping the handles 46, 47. By appropriate adjustment of the brake 45 on the H:\me1indaf\keep\Speci'a\P60G03 wrapping apparatus.doc 20/04/06 -8spool 41 and operation of the electric motor 130 through the control box 60, the turntable 120 is rotated, wrapping the plastics wrap around the product. The brake 45 is adjusted to provide a three fold extension which places the wrap under the required tension to wrap the product in film. As the plastics wrap up the product the height of the spool 40 is adjusted via the handles 46, 47 The combination has the advantage that the shrink wrap dispenser 20 can be removed from the load elevating platform 100 which can then be transported using a forklift so that it can carry out the other loading duties. It is a simple matter to attach the wrap dispenser 20 to the elevating platform 100 and it is designed in a manner that it is easy to operate from the control box.

Although the wrapping apparatus is described using plastics film it is understood that any type of wrap is envisages such as paper, metal foil or many plastics.

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Claims (15)

1. A wrapping apparatus comprising: a wrap dispensing spool adapted to be coupled to an elevating load platform; the spool including a substantially vertically extending shaft adapted to accommodate a roll of wrapping material, whereby the roll can axially rotate relative to the spool to facilitate unwrapping of the material; the elevating load platform comprising a turntable supported by a scissor linkage above a base; drive means to rotate the turntable; and control means to control the rotation of the turntable.

2. The wrapping apparatus according to claim i, wherein rotation of the roll of material is controlled by an adjustable brake.

3. The wrapping apparatus according to either claim 1 or 2, wherein the spool includes a mast that supports a sleeve that is axially slidable relative to the mast, the sleeve in turn supporting the shaft that accommodates the roll of wrapping material.

4. The wrapping apparatus according to claim 3, wherein the sliding movement of the sleeve relative to the mast is controlled by a counterweight.

5. The wrapping apparatus according to claim 4, wherein the shaft is secured to extend vertically from a bracket which is in turn secured to the sleeve.

6. The wrapping apparatus according to claim 2, wherein the brake comprises at least one tapered surface that is carried by the shaft to engage the roll of material, position of the tapered surface relative to the roll being H:\melindaf\keep\Speci's\P60603 wrapping apparatus.doc 20/04/06 10 adjustable to vary the force of the brake.

7. The wrapping apparatus according to claim 6, wherein two frusto-conical members are axially positioned at either end of the shaft to respectively engage opposite ends of the roll of wrapping material, the shaft having the threaded end on which a screw threaded nut is positioned so that rotation of the nut presses the inclined surfaces into increased engagement with the roll of wrapping material to increase the braking force on that roll.

8. The wrapping apparatus according to any one of the preceding claims, wherein a clutch is used to control rotation of the turntable.

9. The wrapping apparatus according to any one of the preceding claims, wherein an electric motor is positioned adjacent the turntable, the output shaft of the motor being adapted to cause rotation of the turntable.

The wrapping apparatus according to any one of the preceding claims, wherein the wrap dispensing spool includes a wheeled base that is adapted to be attached to the load platform.

11. The wrapping apparatus according to claim 10, wherein the wheeled base has a plug or socket that engages a socket or plug on the load platform when the base is attached to the load platform.

12. The wrapping apparatus according to claim 11, wherein latches hold the wheeled base in attachment to the load platform.

13. The wrapping apparatus according to any one of the preceding claims, wherein a control panel is mounted to H:\me1indaf\keep\Speci S\P60603 wrapping apparatus.doc 20/04/06 11 the spool, the control panel being adapted to be connected to a source of mains electricity, the control panel in turn being connected via the plug and socket to the platform assembly to, in turn, be connected to the electric motor to effect drive of the turntable.

14. The wrapping apparatus according to any one of the preceding claims, wherein the wrap dispensing spool comprises a mast pivotally secured to a base plate, the mast being pivotable from a folded position in which it extends parallel to the base plate to an erect operative position in which it extends mutually perpendicular to the plane of the base plate.

15. A wrapping apparatus substantially as herein described with reference to and as illustrated in the accompanying drawings. Dated this 20th day of April 2006 AMIATA HOLDINGS PTY LTD By their Patent Attorneys GRIFFITH HACK Fellows Institute of Patent and Trade Mark Attorneys of Australia H:\me1indaf\keep\Speci's\P60603 wrapping apparatus.doc 20/04/06