FR2545061A2 - Method for forming loads of objects surrounded by a cover made from heat-shrinkable material, device for implementing it and load obtained by means of this method - Google Patents

Abstract

This method relates to the formation of loads of articles 1, placed on a pallet 2 and surrounded by a cover 3 made from heat-shrinkable plastic. According to the main patent, the objects 1 are loaded in the cover 3 while the latter is held by a perforated but rigid belt placed around the pallet 2, then the cover is folded over the objects and heated through the belt which is finally withdrawn. According to the present addition, the lower part of the cover 3 is joined to the pallet 2 before positioning of the belt and introduction of the objects 1. Application to the formation of loads of objects which cannot be stacked and which tend to disperse.

Description

"Method for forming burdens of surrounded objects
a cover in heat-shrinkable material, device
for its implementation, and burden obtained by this process "
The present invention relates to a process for the formation of bundles of objects surrounded by a cover of heat-shrinkable material, and it allows, more particularly, the production of bundles of non-stackable objects, placed on a pallet and covered with a heat shrinkable plastic cover.

 To this end, the main patent already provides a process which essentially consists in putting in place an openwork, rigid and heat-resistant belt, around the pallet to be loaded, placing the cover inside the belt, in contact with the pallet and against the interior walls of said belt, while the upper part of the cover is folded down outside the belt, to fill with objects the container thus formed by the cover, to be folded over the objects piled the upper part of the cover previously folded outside, to heat the cover, causing it to shrink, through the perforated belt, and finally remove this belt.

This process, using a belt, for example metallic, which laterally delimits a volume corresponding to the burden to be formed, makes it possible to shape this burden by placing the objects directly in the cover, while maintaining them, then retracting the cover on these objects without ceasing to maintain them, until the cover has regained the necessary resistance it loses while being heated.After removing the belt which surrounds the burden during its entire formation, we obtain on the pallet a Perfectly made burden, whatever the shape of the objects, which gives the possibility of forming burdens with objects having a natural tendency to roll on each other or to disperse
In the mode of implementation of this process described by the main patent, the cover of heat-shrinkable plastic, intended to surround the objects, is placed above the pallet and inside the rigid belt, but this cover is not linked to the palette. I1 results in particular that the burden of objects, even if it is properly tightened in the cover, risks slipping or tipping over the pallet during handling and transport operations.

 The present addition avoids this drawback by providing an improved mode of implementation of the same method which allows the load to be secured on the pallet, and which moreover provides other advantages set out below.

 To this end, in the method according to the present addition for the formation of bundles of objects, the lower part of the cover of heat-shrinkable plastic is secured to the pallet, before the rigid belt is placed around the pallet and the introduction of objects inside the cover.

 This improvement therefore leads to the implementation of a kind of special packaging, consisting of a pallet and a cover made of heat-shrinkable plastic material, surmounting the pallet and linked to it.

 The pallet, made of molded plastic material which is sufficiently rigid and resistant, advantageously has over its entire periphery a groove in which is adapted the lower part of the cover made of heat-shrinkable plastic material, initially having the shape of a sheath. The connection between this sheath and the periphery of the pallet can be made as desired by simple embedding, by local retraction, by gluing or by welding. To facilitate mounting of the sheath on the pallet, the perimeter of said sheath in its lower part will preferably be chosen slightly smaller than that of the peripheral groove of the pallet. In addition, a bead can be formed at this lower end of the sheath, either by simply folding the sheath on itself over a width of a few centimeters, or by bringing a strip of material. This gives the base of the sheath , a reinforced part which can be either simply introduced and maintained, thanks to its elasticity, in the groove of the pallet, or introduced then heated for retraction, or welded or glued in said groove.

 The design of this packaging allows, either, the combination of the sheath and the pallet in the factory, so that the user has a ready-to-use packaging, or the junction of the sheath and the pallet by the user himself with relative ease, at the time of employment, that is to say just before the making of the burden.

 When the burden of objects has been removed, the pallet can be reused by receiving a new sheath.

 The initial connection between the cover and the pallet involves securing the burden of objects with the pallet, once the burden is formed and tightened in the cover. This burden therefore no longer risks slipping or capsizing during handling or transport. In addition, the cover does not need to be closed at its lower part since the pallet provides a bottom, which allows a saving of material.

 The use of a specific pallet, in particular of molded plastic, also makes it possible to improve the process of forming the burden of objects. In particular, anchoring holes can be provided in the feet of the pallet, in order to allow rapid adaptation of the rigid belt used for the formation of the burden of objects according to the general principle of the invention. The resistance of the belt to the thrust of the load is thus reinforced, in particular by reducing its range on the long sides of the pallet thanks to intermediate anchoring points. In addition, the connection obtained between the pallet and the wrapping belt allows the possible displacement of the assembly, during loading, without disadvantage.

 Obtaining loads of stable and well-secured objects on the pallets also makes it possible to envisage stacking several similar loads, thanks to relatively simple and economical additional arrangements. It is indeed sufficient to provide, at the four angles of the pallet, holes suitable for receiving the feet of corner pillars intended to be joined, at their peaks, by a rectangular frame or tray. During the formation of the package, the corner pillars already placed in the corresponding holes of the pallet can be maintained by means of clips provided at the four upper corners of the wrapping belt. After loading the objects, the cover is retracted either below or preferably above the frame or the tray.

 The configuration of the frame or tray and the feet of the pallet is provided to facilitate the positioning of one load on the other. The corner pillars, of standardized length, can receive extensions to adapt to the actual height of the load contained in the cover.

In any case, the object of the present addition will be clearly understood with the aid of the description which follows, with reference to the appended schematic drawing illustrating, by way of nonlimiting example, an embodiment of this method for the formation of burdens of objects surrounded by a heat-shrinkable cover
Figure 1 is an overall perspective view of a burden of objects formed by implementing the method according to this addition;
Figure 2 is an exploded perspective view of a set "palet te + sheath", with complementary elements for stacking the burdens
Figure 3 is a perspective view of a bundling belt, specially adapted for the implementation of the method according to the present addition
Figure 4 shows, on a larger scale, a detail of the upper part of one of the corner pillars and of the tray provided for stacking
Figure 5 shows details of the pallet, the lower end of a corner pillar, and the connection between the sheath and the pallet.

 As already described in the main patent, the method relates to the formation of bundles of objects (1) placed on a pallet (2) and surrounded by a cover (3) made of heat-shrinkable plastic material - see FIG. 1. This formation is carried out at using an openwork but rigid metal belt (4), shown in Figure 3, which is initially placed around the pallet (2), and removed at the end of the formation of the burden.

 According to the present addition, the cover (3) is constituted by a sheath, in heat-shrinkable polyethylene or other material having the same property, the open lower end of which is secured to the perimeter of the pallet (2). For this purpose the pallet (2) has a peripheral groove (25) - see also Figure 5- which receives the lower part of the sheath (3). This lower part is reinforced by a lining (26) achievable by folding the sheath on itself. The bead thus formed is tightened elastically, retracted by thermal effect, glued or welded in the groove (25). The pallet (2) can be made of any material, but it is preferably made by molding plastic material, making it possible to easily obtain the groove (25) and the other features described below.

 The formation of the burden is thus carried out starting from a "pallet + sheath" assembly, visible in FIG. 2, appearing as a package closed in its bottom but remaining initially open at its upper part. It goes without saying that before use, the assembly can be delivered and stored in a reduced volume, the sheath (3) being folded flat on the pallet (2).

 At the time of use, the belt (4) is placed around the pallet (2). As described in the main patent, and as shown in FIG. 3, this belt (4) has four faces so as to completely surround the pallet (2). Each longitudinal face, intended to be placed along a long side of the pallet (2), is constituted by a rectangular frame (5) with two uprights (6) and two crosspieces (7), which support a trellis (8 ). Similarly, each transverse face, intended to be placed along a small side of the pallet (2), is constituted by a rectangular frame (9) with two uprights (10) and two crosspieces (11) which support a trellis (12).

 The lower crosspieces (7 and 12) have hooks (27) which are introduced into anchoring holes (28) made in the different feet (29) of the pallet (2). The belt (4) is thus positioned precisely and quickly on the pallet (2). The sheath (3) can then be applied against the inside of the belt (4), while its upper part is folded out of said belt. The objects (1) to be bundled are placed inside the sheath (3). Then the upper part of the sheath (3) is folded over the piled objects, and one proceeds to the heating of this sheath (3) through the lattices (8,12) of the belt (4). The sheath (3) thus retracts around the package of objects (1), while its upper part closes by welding at the top of this package of objects. Finally, the belt (4) is removed and we obtain a burden as shown in Figure 1, wherein the objects (1), retaining the shape given by the belt (4), are clamped in the retracted sheath (3) and are further secured to the pallet (2).

 Before filling the sheath (3) with the objects (1), it is possible to place, in holes (30) provided at the four angles of the pallet (2), corner pillars (31) provided at their lower ends of heads (32) adapted to the holes (30) - see Figures 2 and 5. The four corner pillars (31) are held in a vertical position, when the burden of objects is formed, by means of clips ( 33) provided at the upper corners of the belt (4) - see figure 2. The tops of the four corner pillars (31) are arranged to receive a rectangular plate (34), the sheath (3) being able to be closed either at below, or preferably above the plate (34). This plate (34) has, on its perimeter, a profile (35) well indicated in Figure 4, complementary to a chamfer (36) produced on the feet (29) of the pallet (2). These arrangements allow stacking two or more identical loads, with precise positioning of the pallet (2) of the upper load on the plate (34) of the lower load.

 As shown in Figure 4, a riser (37) can be interposed between the top of each corner pillar (31) and the plate (34), to adapt the position of this plate (34) to the actual height of the load of objects. Optionally, two or more similar risers are fitted together as well as with the top of each pillar and the plate, according to the same assembly principle.

We would not depart from the scope of this addition
- by making the pallet (2) in any suitable material, such as wood
- by providing either complete sealing of the sheath (3) and its connection with the pallet (2), or on the contrary openings or perforations for ventilation, depending on the nature of the objects (1) to be bundled in the case of 'A sealed connection, vacuum packaging can also be considered;
- by providing various configurations, always complementary to the plate (34) and the feet (29) of the pallet (2), for stacking;
- by replacing the solid plate (34) with a rectangular frame or by any other equivalent perforated structure.

Claims (10)

 1. Process for the formation of bundles of objects placed on a pallet and surrounded by a shrinkable plastic cover, in which an openwork belt (4), - rigid and heat resistant, is placed around the pallet (2) to be loaded, the cover (3) being arranged inside the belt (4), in contact with the pallet (2) and against the interior walls of said belt (4), while the upper part of the cover is folded outside the belt (4), we fill with objects (1) the container thus formed by the cover (3), we fold over the piled up objects (1) the upper part of the cover, the cover (3) is heated, causing it to retract, through the perforated belt (4), and finally this belt (4) is removed, according to claim 1 of the main patent, characterized in that the lower part of the heat-shrinkable plastic cover (3) is secured to the pallet (2), before setting lace of the rigid belt (4) around the pallet (2) and the introduction of objects (1) inside the cover (3).  2. A method of forming bundles according to claim 1, characterized in that the pallet (2) has over its entire periphery a groove (25) in which is adapted the lower part of the cover made of heat-shrinkable plastic (3), having the shape of a sheath, the connection - between said sheath (3) and the periphery of the pallet (2) being achievable in particular by embedding, by local retraction, by gluing or by welding.  3. A method of forming bundles according to claim 1, characterized in that a bead (26) is formed at the lower end of the sheath (3) introduced into the peripheral groove (25) of the pallet (2), for example by folding the sheath on itself.  4. A method of forming bundles according to any one of claims 1 to 3, characterized in that from the anchoring holes (28) are provided in the feet (29) of the pallet (2), for the adaptation of the belt (4).  5. A method of forming bundles according to any one of claims 1 to 4, characterized in that there are further provided, at the four angles of the pallet (2), holes (30) suitable for receiving the feet  (32) of corner pillars (31) intended to be joined, at their vertices,  by a rectangular frame or tray (34), to allow stacking of several loads.  6. A method of forming burdens according to claim 5, characterized in that the cover (3) is retracted above the frame or upper plate (34).  7. A method of forming burdens according to claim 5 or 6, characterized in that risers (37) are interposed between the top of each corner pillar (31) and the frame or upper plate (34).  8. Device for implementing the method according to all of claims 4 and 5, characterized in that the belt (4) has, at its lower part, hooks (27) - able to be introduced into the holes anchor (28) of the pallet (2), and in that this belt (4) comprises, at its upper corners, clips (33) intended to hold the pillars (31).  9. Burden of objects (1) placed on a pallet (2) and surrounded by a shrinkable plastic cover (3) secured to the pallet (2), this burden being obtained by the method according to any one of claims 1 to 7.  10. Burden of objects according to claim 9, characterized in that it comprises a frame or upper plate (34) with a profile (35) complementary to that of the feet (29) of the pallet (2), for its stacking .