Abstract:
A deck ( 10 ) for mounting a load which may be thin and disposable or returnable. The edge ( 11 ) of the deck is adapted (by means of a concave section, for example) so as to engage with shrink or stretch or heat wrap plastic film whereby no plastic film need be wound around the underside of the deck. In this way the plastic film is kept out of contact with, for example, the roller of a roller conveyor.

Description:
BACKGROUND TO THE INVENTION 
       [0001]    The present invention relates to a means for mounting a load. 
         [0002]    Conventionally pallets are used to mount a load and enable a forklift truck to engage under the load to lift the load. The forklift truck may be motorised or may be a hand operated forklift truck ie a so called pallet truck. The pallets which are often of wood comprise a top deck and a lower deck spaced from and connected to one another by blocks of wood, the top and lower decks being spaced so as to allow the forks of a forklift truck to enter between the top and lower decks so as to lift the top deck and hence a load mounted on the top deck. Pallets are sometimes made of other materials such as steel. 
         [0003]    Pallets when loaded at a factory are then transported bearing the load in trucks to the customer. Once they have been unloaded and the goods removed from the load, the empty pallets have to be returned to the factory. In view of the weight of the pallets, this can be a considerable environmental cost 
         [0004]    Substantial number of pallets are required and although they are intended to be returnable, in practice a manufacturer of goods has to provide many pallets and the customer tends to be left with large numbers of pallets which have to be returned to the manufacturer if they can be identified. In practice, retail outlets often collect large numbers of pallets which take up a considerable amount of room and are generally inconvenient. 
         [0005]    Another problem is that the loads are commonly held down to the pallets by means of plastic sheeting in the form of shrink wrap sheeting, or stretch wrap sheeting. In the case of shrink wrap sheeting, the sheeting is wound around the pallet and the load and heat is applied to the sheet which shrinks to firmly hold the load down to the pallet. In the case of stretch wrap sheeting, once again, a film of the plastic is passed around the pallet and the load under tension and this holds the load to the pallet. 
         [0006]    A problem with the use of plastic sheeting in this way is that if the pallet passes over a roller conveyor system, then the plastic can get caught up in the rollers and this is highly detrimental in that it may require the roller conveyor to be stopped and repaired or cleaned. 
         [0007]    The present invention reduces or removes these problems. 
       SUMMARY OF THE INVENTION 
       [0008]    The present invention provides, according to a first aspect, a deck for mounting the load which may be thin and disposable or returnable. In place of the pallet with two spaced decks, a single deck is used and this requires that when the deck and load is to be stored at the factory before dispatch, or is stacked in a truck for transportation, or is stored at its destination (e.g. customer), then suitable racking means must be provided which enables the forks of a forklift truck or other similar means to be able to engage the under surface of the deck to lift it. 
         [0009]    In addition, the edge of the deck is adapted so as to engage with shrink or stretch or heat wrap plastic film whereby no plastic film is wound around the underside of the deck. In this way the plastic sheeting is kept out of contact with, for example, the roller of a roller conveyor. 
         [0010]    Thus the invention comprises a deck for mounting a load comprising a single layer having edges, each edge of the deck being adapted so as to engage with an edge of shrink or stretch or heat wrap plastic film whereby no plastic film is wound around the underside of the deck. 
         [0011]    Preferably each edge of the deck may be provided in the form of a groove which may be in the form of a concave channel or V shaped channel, and in a preferred arrangement the channel may include teeth means to engage with the plastic sheet. The channels may include means to prevent channels of adjacent decks from engaging with one another which would otherwise cause problems in lifting one deck at a time. 
         [0012]    It will also be understood that by replacing the pallet with a single deck, the weight and indeed volume of the decks to be returned from the retailer to the manufacturer is considerably reduced. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0013]    Preferred embodiments of the invention will now be described by way of example and with reference to the accompanying drawings in which:— 
           [0014]      FIG. 1  is a perspective view of a deck according to the invention, 
           [0015]      FIG. 2  is a perspective side view of part of the deck of  FIG. 1 , 
           [0016]      FIG. 3  is a part cross section of the edge of the deck of  FIG. 1 , 
           [0017]      FIG. 4  is a view of racking on which decks of the type shown in  FIGS. 1 to 3  may be stacked with loads stacked thereon, 
           [0018]      FIG. 5  shows the racking of  FIG. 4  with a deck and load mounted thereon, 
           [0019]      FIG. 6  shows a side view of a truck for transportation of the load to its destination adapted to mount decks of the type shown in  FIG. 1 , with loads thereon, 
           [0020]      FIG. 7  shows a perspective detail of a second, alternative deck with a deeper concave section without teeth, 
           [0021]      FIG. 8  is a perspective view of a third, alternative, deck according to the invention, 
           [0022]      FIG. 9  is a perspective side view of part of the deck of  FIG. 8 , and 
           [0023]      FIG. 10  is a part cross section of the edge of the deck of  FIG. 8 . 
       
    
    
     DESCRIPTION OF PREFERRED EMBODIMENTS 
       [0024]    Referring to  FIG. 1  there will be seen a deck  10  comprising a rectangular sheet. The deck  10  may preferably be of a plastic material and is preferably of injection moulded plastic. The plastic material is selected for the use envisaged and may be high density polyethylene or polypropylene. It may however be of other material such as wood or plywood. 
         [0025]    The deck may have dimensions appropriate to its use which is typically 1200 mm×1000 mm and of a thickness of 45 mm in the UK, typically 1200 mm×800 mm and of a thickness of 45 mm in Europe, typically 1220 mm×1016 mm and of a thickness of 45 mm in the US and typically 1100 mm×1100 mm and of a thickness of 45 mm in Japan. The thickness may vary depending on the load to be mounted on the deck. 
         [0026]      FIG. 2  shows a perspective side view of part of the deck  10  and as can be seen each edge  11  of deck  10  has a channel in the form of a concave section  12 . However other cross section channels are envisaged including V section channels. The concave section  12  may extend from adjacent an upper surface  13  to adjacent a lower surface  14  of the deck  10 . In the illustrated arrangement the concave section  12  does not extend completely to the upper and lower surfaces  13  and  14  but is spaced therefrom to retain an upper and lower lip  16 ,  17  respectively between the concave section  12  and the upper and lower surfaces. The depth and the cross section of the lips  16 ,  17  may be chosen for the particular circumstance. The cross section of the lips may be convexly curved. 
         [0027]    The arrangement shown in  FIG. 2  is a preferred arrangement since it is symmetrical about its middle plane and thus can be used either way up. If however there is to be a preselected upper and lower surface of the deck then the deck may be able to be non symmetrical about its middle plane and only an upper lip may be provided, the concave section  12  running into the lower surface, so that the external dimensions of the lower surface  14  may be less than those of the upper surface  13 . 
         [0028]    In a preferred arrangement, the surface of the concave section  12  includes studs or teeth  18 , the studs or teeth  18  being provided in two rows running parallel to and adjacent the upper surface  13  and lower surface  14 . 
         [0029]      FIG. 3  shows a cross section through the edge  11  of the deck  10 , shows the shape and formation of the concave section  12 , and of the studs or teeth  18  in more detail. It will be noted that the studs or teeth have a generally smooth but sharp shape. 
         [0030]      FIG. 6  shows an alternative section of concave section  12  which is much deeper than that of  FIGS. 2 and 3  and without teeth  18 . 
         [0031]    The deck  10  shown in  FIGS. 1 to 3  may be used with the staging  19  as illustrated in  FIG. 4 . The staging comprises two upright frames  21 ,  22  spaced apart from one another and joined by a lower frame  23 . The lower frame  23  is horizontal and comprises two frame members  26 ,  27  which extend between the upright frames  21 ,  22 . Extended between the frame members  26 ,  27  are horizontal bars  28  which are spaced from one another. As shown in  FIG. 5 , the deck  10  may be mounted on the bars  28 , the bars  28  spacing the deck  10  from the lower frame members  26 ,  27 . 
         [0032]      FIG. 5  shows a load  29  mounted on the deck  10  and as is clear, the load is generally of overall width and length similar to that of the deck  10 . As is well known, loads are commonly connected to pallets, or in this case the deck  10 , by means of shrink wrap plastic sheeting or stretch wrap plastic sheeting  30 . 
         [0033]    Shrink wrap plastic film is a material usually of polymer plastic film. When heat is applied to the shrink wrap plastic film material, it shrinks tightly over what ever it is covering. Shrink wrap plastic film is commonly used to over wrap many types of packaging. The most commonly used shrink wrap is polyolefin. Other shrink films include PVC. 
         [0034]    Stretch wrap or stretch film is a highly stretchable plastic film that is wrapped around items under tension. The elastic recovery property inherent in the material keeps the items tightly bound. The most commonly used stretch wrap material are linear low density polyethylene or LLDPE. Many films have about 500% stretch at break but are usually only stretched to about 100-300% in use. Once stretched the elastic recovery is used to keep the load tight. 
         [0035]    In use, to hold the load to the deck, a roll of stretch wrap film is held with its axis vertical, and with the lower edge  31  of the film  30  adjacent the edge of the deck. The roll is then moved around the load under tension to stretch the film and in that way the lower edge of the stretch wrap film engages with the edge of the deck  10  and, in particular, engages in the concave section  12 . As shown in  FIG. 3 , the stretch wrap film  30  engages with the uppermost row of teeth  18 . 
         [0036]    In the case of using shrink wrap plastic film, the plastic film may be applied from a vertical roll with its lower edge  31  engaging in the concave section  12  of the deck and the shrink wrap film is then shrunk by the application of heat, either through a hand held blower or alternatively by passing the deck and load through a heated tunnel. 
         [0037]    In this way it is possible to securely attach the load to the deck  10  without any of the shrink or stretch wrap film extending below the deck  10  where it might engage with rollers on a conveyor roller if the deck  10  and load are moved along such a conveyor roller. The concave section  12  and the teeth securely engage the lower edge of the plastic film and keep the film away from the lower surface of the deck. 
         [0038]    The teeth  18  are arranged to be of a shape which engages the plastic film securely without tearing it. Thus the height of the teeth should be chosen to aid engagement with the film and the shape and smoothness of the tip of each tooth should be chosen so as not to tear the plastic film. 
         [0039]    The arrangement of  FIG. 6 , because of the greater depth of the concave section might not need teeth, and a further advantage is that the deep slot can store any torn edges of the plastic film without them hanging down below the lower surface of the deck. 
         [0040]    Returning to  FIG. 5 , it will be understood that the load attached to the deck  10  can be readily removed from the staging  19  by inserting the forks of a fork lift truck below the deck and parallel to the bars  28 . 
         [0041]      FIG. 6  shows a side view of a truck for use with this arrangement in which the truck includes bars  32  corresponding to the bars  28 . The fork lift truck can deposit the deck  10  and load  29  onto the bars  32  for transportation. When the load reaches its destination, the load may be removed along with the relevant deck  10  and then mounted on staging  19  similar to that shown in  FIG. 5 . In this way, the decks  10  can be returned when the load has been dismounted and the weight of the return decks is considerably less than that of standard pallets. 
         [0042]    Whilst the arrangements of deck  10  so far described are very efficient and useful, a problem can sometimes occur in that when the decks are arranged side-by-side, for example, when being stacked during transportation, the concave sections  12  of adjacent edges  11  of adjacent decks may engage with one another. When one of the decks is to be lifted, then this engagement of the two edges of adjacent decks will prevent one deck being lifted without the other. 
         [0043]    It is therefore desirable to provide an arrangement whereby to prevent the concave sections  12  of the edges of adjacent decks  10  from engaging with one another and such an arrangement is shown in  FIGS. 8-10 . 
         [0044]      FIG. 8  shows a perspective view of a deck  10  in which the concave sections  12  of each edge includes several (three in this embodiment but other numbers can be used) raised areas  50  to prevent engagement of adjacent concave sections of adjacent decks. 
         [0045]    The raised areas  50  are shown in  FIG. 8 , and  FIG. 9  shows a perspective view of part of the edge of one deck between the lines  9 A and  9 B of  FIG. 8 , which shows these raised sections.  FIG. 10  is a section on the line A-A of  FIG. 8  and shows the exact cross-section of the raised area  50 . 
         [0046]    As is clear from  FIG. 8 , there are 3 raised areas  50  on each side of the deck. 
         [0047]    In this way, it is not possible for the edges of adjacent decks to overlap and their concave sections inter-engage. 
         [0048]    Although not shown in  FIGS. 8-10 , the decks may include any of the other features shown in the earlier figures, for example, studs or teeth  18  or deeper concave sections  12  of the type shown in  FIG. 6 . 
         [0049]    The invention is not restricted to the details of the foregoing example.