EP0099827B1 - Separator trays for stacked loads - Google Patents

Description

Even called flat, the bottom of glass containers has a certain concavity, so as to create a heel which gives them a regular peripheral reach capable of giving them good stability, sufficient even for it to be possible to stack these containers, jars for example, in several beds separated from each other by relatively flexible spacers, usually made of corrugated cardboard sheets. Such a method makes it possible to store them when they are full and closed but already, before use, while they are still empty and open.

To constitute the load, it is enough, after having deposited a first bed on a pallet, to cover it with a cardboard interlayer to be able to put a new one and so on, in order to create a lot which, finally protected and belted by a retractable plastic cover, can then be transported from one stage to another of the manufacturing, but also during the sale and with a view to delivery, therefore over fairly large distances.

We thus manage to form large batches and, for example, to send bottles of 20 to 150 ci by pallets of 6 to 10 beds of 100 to 400 bottles approximately, which can also be stored at three heights. that is to say in piles of more than 6 meters. If the cardboard interlayer is of low cost, it should be noted that it tends to take moisture which makes it also tearable and that, soiled and marked by its use, it cannot be reused but only sold to papermakers who recover the material.

The solution which has just been described rests on the fact that the containers, arranged side by side in. staggered according to a generally triangular network are tightened barrel against barrel by the retraction of the cover, which gives the package sufficient cohesion; but it follows that during transport and under the effect of shaking, these containers rub against each other, which at least locally deteriorates their surface. This drawback is acceptable on products of average quality if the transport distances are not excessive but any other case requires additional precautions which lead to spacing the containers of each bed, this in practice according to a square mesh, even slightly rectangular: it is clear that the stability of the load then becomes all the less easy to obtain as these containers are narrower, which leads in particular, if they are bottles, to separate them by cardboard braces which hold them in place with a certain lateral tightening before the installation of the cover as after its removal.

This method is satisfactory in terms of quality but it is costly on the one hand because of the additional consumption of cardboard it causes, on the other hand because of the labor it requires, in particularly in the case of decorated or satin-finished bottles which frequently have to undergo several stages of transport between their successive finishing operations.

This is why many attempts have been made to provide a simpler solution by the use of an intermediate plate capable of keeping the articles apart, according to a well known principle for the packaging of fragile objects, to the using a combination of housings intended to receive on the one hand the lower part, on the other hand the upper part of these objects, in this case the base and the neck of the bottles. Attempts have therefore been made to use reusable trays of molded or thermoformed plastic, or even trays of composite structure associating, for example, sheets of plastic and corrugated cardboard.

However, these attempts ended in failure: the simplest trays proved to be incapable of giving sufficient stability to the stacking of bottles, which tends to collapse as soon as the cover is removed, and also fail more to prevent mutual erosion of the tray and bottle necks during transport. The most elaborate, without making it possible to overcome all of this difficulty, add to this the disadvantage of too high a cost because they quickly deteriorate with use.

The object of the invention is therefore to provide spacers capable of allowing the handling of fragile articles and in particular glass articles or containers such as high quality bottles, by heavy loads such as pallets containing up to 4000 bottles in bunk beds in which these articles are spaced from each other, loads capable of undergoing storage in piles and transport over long distances without risk of deterioration or collapse when the cover is opened. Its use will make it possible to operate with great simplicity, both to constitute the charges and during the recovery of the articles, therefore to work quickly, and if necessary in a fully automatic manner, that is to say with a great economy of workforce. Such a plate will simply consist of a sheet of material of substantially constant thickness, of the order of a millimeter, formed so as to bring reliefs to the desired spacing; to make it reusable, it will advantageously be a thermoformed thermoplastic material, polyethylene for example.

A similar plate, described by patent FR-A-2 450 753, consists of a flat support sheet with a regular pitch of imprints each comprising two concentric circular ribs but of opposite directions, which form in its center and on a first face a cell capable of receiving the neck of the neck of the containers of a lower bed, at its periphery and on the second face a seat capable of receiving the base of the containers of an upper bed. The free space remaining between the plate and the base in the center of each footprint gives the assembly the desired elasticity to provide each of the successive beds with horizontal support despite the manufacturing tolerances of the bottles.

According to the invention, and in order to eliminate the problems observed, the profile of each imprint of a tray of the same type will on the contrary, towards the center, be close enough to that of the base to bring the imprint in contact with this by stacking. last, with tightening of the plate between the neck of the neck of the receptacles of the lower bed and the base of those of the upper bed, this only opposite the outer rim of the upper lip of the ring of the neck of the former, the heel of the base of the latter always resting on the periphery of the imprint but imposing only a minimal elastic deformation on it.

Preferably, each imprint, while being as close as possible to the profile of the base of the upper container, will provide the ring of the lower container with a housing provided with an enlarged inlet, forming on the upper face of the tray a nipple connected to a annular seat and the top of which will carry a circular step of internal diameter adapted to that of said ring, with a central clearance which will leave only a peripheral crown of width less than that of the rim and a rounded nose of radius of curvature at least equal to that of the outer rim of this drink; the crown will be located, relative to the seat above which, centered on the nipple, is then placed the lower reach of the heel, at a height in principle just lower, taking into account the tolerances, than that of the corresponding return part of the base. The imprint thus draws down a bowl with a central alveolus which offers scope to the bank only on its external rim, in front of which the base will come to rest, the heel of which will however find secondary contact on the annular seat .

To allow the necks of the containers of a first bed to center themselves on the cavities when they are covered with a tray, the inclined portion of the nipple or the conical part of the cavity will have a slope greater than the coefficient of friction of the glass on the material of this intermediate plate, that is to say in practice at least equal to 20%, and a sufficient diameter; the base of the nipple is connected to the bottom either directly or at least via a slight cylindrical trimming, or on the contrary by an asymmetrical groove compensating for any excess height of the nipple.

The imprints will advantageously be separated by a quincunx of moles forming on the upper face of the housings able to immobilize the caps of the containers.

• Figure 1 en vue de dessus, l'angle d'un plateau à maille carrée ;
• Figure 2 une coupe d'un plateau semblable, selon la ligne II-II de la figure 1, avec une partie arrachée ;
• Figure 3 une coupe du plateau selon la ligne III-III de la figure 1 ;
• Figure 4 un détail de la couronne de serrage selon IV de la figure 3 ;
• Figure 5 la constitution d'une charge ;
• Figure 6 en vue de dessus, l'angle d'un plateau à maille triangulaire ;
• Figure 7 une coupe de ce plateau selon la ligne VII-VII de la figure 6.

Two implementations of the invention will be described below with reference to the figures which show:

• Figure 1 in top view, the angle of a square mesh tray;
• Figure 2 a section of a similar tray, according to line II-II of Figure 1, with a portion cut away;
• Figure 3 a section of the plate along line III-III of Figure 1;
• Figure 4 a detail of the clamping ring according to IV of Figure 3;
• Figure 5 the constitution of a charge;
• Figure 6 in top view, the angle of a triangular mesh tray;
• Figure 7 a section of this tray along line VII-VII of Figure 6.

FIG. 1 shows a plate 1, made of polypropylene, with a thickness of 0.8 to 1.6 mm approximately depending on the case, the bottom 2 of which bears circular imprints 3, in relief according to a square mesh which can range from 80 at around 120 mm for 75 cl bottles, at the rate of 9 to 11 rows of 11 to 14 cavities for example. These are further separated from each other by moles 4 of quadrangular shape arranged in staggered rows. A rim 5 connecting projecting elements 4 ′ whose shape partially reproduces that of the moles 4 stiffens the whole of the plate.

As can be seen in the section of Figure 2, each tray, intended here to serve as an interlayer between two beds of 75 cl bottles with pricked bottom, will rest on the necks 6 of the bottles of the lower bed and will in turn receive the lower peripheral surface or heel 7a of the caps 7 of the bottles of the upper bed, the imprints 3 coming to be housed in the space left free by the stitching 8. These imprints are formed of nipples of generally frustoconical shape whose axes X are spaced d '' a distance slightly greater than the maximum diameter of the bottles, thus preventing them from touching each other.

The top of the conical wall 9 of the nipples carries in step a crown 10 which has a rounded nose 11, their upper face forming a button 12 protruding slightly thanks to a narrow conical wall 13, while at their base is a clipping cylindrical 14 of low height around which the bottom 2 constitutes a horizontal annular seat 2a.

As best shown in the detail in FIG. 4, the rounding of the nose 11 is preferably connected to a rounded edge 15, to form a narrow vertical belt whose internal diameter adjusts without friction to that of the ring and it has internally a radius of curvature r, greater than that of the outer rim of the rim by an amount at least equal to the tolerance of the diametral play and preferably of the order of twice; in practice, this radius may reach 1.5 mm. The imprint thus forms downwards a cell capable of being housed on the ring by enclosing it in the corner to secure the various bottles of the lower bed.

The button 12 has a diameter greater than that of the internal edge of the rim and thus leaves only a narrow portion 16 located from the bottom, placed, above the seat 2a, at a height h lower by a few tenths of a millimeter to the height p that the bite has at the level of the nose 11, and of a width which is quite clearly less than the thickness of the lip.

The base radius of the nipple exceeds at least about 1 cm that of the bottle ring while the slope of its wall 9, in any case greater than 20%, preferably corresponds to an angle of 30 to 45 °, its total height therefore reaching about 0.5 to 1 cm.

The main purpose of the clipping 14 is to · facilitate the manufacture of the mold but also increases the flat surface belonging to the bottom 2, therefore its flexibility.

In its simplest form, a tray in accordance with the invention could exclusively comprise the imprints 3, projecting from a flat bottom or bearing, if necessary, a rib avoiding the seats 2a: the imprints can, by example, forming light basins on the bottom, which increases rigidity; if these basins are close enough to join, there remains between them only moles 4 mentioned above.

As shown in Figures 2 and 3, they have a significant height, greater than that of the nipple. They have four sidewalls 17, vertical (apart from the manufacturing spindles, which also allow them to be stacked empty under a small volume, possible stops, not shown here, avoiding jamming) or of a profile corresponding substantially to that of the caps. bottles ; these sides preferably follow the circular form of the base in this case and are therefore of revolution, four to four, around the axes X. They advantageously connect to the bottom 2 by rounded portions 17a and can have rounded inlets 17b. At the four angles of each mole, they are limited by cut sides 18 which, to avoid brutal shapes, also have connections 18a and if necessary 18b, which, in this case, creates on the bottom, a mole to another, a rib 19.

Without being strictly essential, the moles 4, with the ribs 19 which connect them two by two, increase the overall rigidity of the plates by preventing the surface of the latter from presenting any straight portion; they also help to center the bottles during their installation and then to keep them in place.

This is why it may be advantageous to provide along their flanks 17 a series of clearances 17c sufficient to leave only partial spans 17d having at their upper part a pointed end. Indeed, various models of bottles have, projecting from the lower part of the barrel, fingers or locating pins used mainly for labeling. When forming a bed, and unless complicated precautions are taken, these fingers are placed randomly so that they will often appear in front of one or the other of the moles 4. Conducted by the side walls 17th of the ranges 17d, they will then be placed in the clearances 17c as shown in 7b, FIG. 3. This indentation makes it possible to laterally guide the caps 7 relatively narrowly along the ranges 17d to improve the rigidity of the stacking.

It should be noted that the mesh of the trays could just as well be rectangular, or the shape of the nipples deviate from the circular shape, for loading ovalized, square or flat bottles etc., with a more complex nesting if necessary.

To constitute the load, a first tray is placed on a pallet, then a first series of bottles is deposited, at the appropriate spacing, which are housed between the moles 4, centering, even approximately, on the imprints 3 and the bed thus formed is covered with a second plate identical to the first: thanks to the conical inlets formed by the walls 9 of the nipples, the necks of the bottles come from themselves fitting onto the cells defined by their crowns 10 , which secures these bottles. The outer rim 6a of the rim comes to bear at 3a in the rounding of the nose 11, the seam of the ring mold, which is usually located on its internal edge 6b, on the contrary not coming into contact with the plate but being placed at the inside the free space created by the button 12, as shown in FIG. 4.

The bottles of the second bed are in turn deposited, the heel of which then comes into contact with the seat 2a along a line 2b: the weight of each of them is enough to cause the support zone to bend, due of its planar shape, and this until the puncture, catching up with the small difference in height which existed initially in this area, comes in turn to bear obliquely in 3b on the nose 11, without, on the other hand, its top presses the button 12. This completes the centering of the bottle on the circular imprint 3, the effort being exerted on the angle, along the double contact line 3a-3b, while any possibility of deformation additional of the plate whose subsequent loosening could cause the load to collapse is prohibited in the vertical direction. If, however, the height h was greater than the corresponding height p, there would cease to be a frank bearing of the heels along the secondary contact line 2b and the stability of the bottles on the plate would quickly become insufficient.

The phenomenon is repeated for the laying of the third bed and so on, so that the bottles are stacked in rigid columns inside which they are separated by the thicknesses of the trays alone. We see that the weight is transmitted directly at the level of the crown 10 while the seat 2a only serves to maintain the verticality.

Finally, a cover is placed, then a cover, the retraction of which then creates sufficient tightening, vertically to immobilize the bottles of each column, horizontally to hold the successive trays together, the system leaving in this latter direction a cer elasticity. The load can thus withstand without disadvantage the acceleration or side impact caused by transport.

It is preferable not to constitute the cover of a simple cardboard or other plate, but to still employ a tray capable of joining the bottles of the upper bed by their necks.

For this purpose, a plate identical to the previous ones is capable of supporting the bending that the retraction of the cover imposes on its edges but, if one wants to be able to stack a second load on the first, it is necessary that the flat bottom of the pallet corresponds essentially to the top of the imprints 3: it would indeed punch or, at the very least, deform the plate if the force were to be exerted on the upper face of the moles 4, that is to say in false while, suitably drawn, the buttons 12 on the contrary are capable of supporting their successive loads and the efforts due to transport.

If the height of the moles is greater than that of the nipples, it is therefore necessary, to allow the vertical stacking of several pallets, to use for the cover a tray of a different model, provided only with alveoli or imprints similar to the imprints 3, or more simply a network of corrugations not only capable of stiffening it but constituting on its lower face rectilinear grooves capable of coming to fit on the necks of the bottles of the various rows of the upper bed, to maintain them at least in one direction.

Such a tray is shown diagrammatically under the reference 21, FIG. 5, before it is placed on the last bed of bottles of a charge being built up. The dimensions of the plate 21 are slightly smaller than those of the intermediate plate 1 because it is advantageous for it to only cover the necks of the bottles. Given that the beds shown in the figure consist of rows of only four bottles, the tray 21 only has two grooves 22, of rectangular layout, concentric and whose profile, not detailed, of course corresponds to that of the rings of these bottles: once the tray is placed on the upper bed, the latter are housed there, which is enough to immobilize the entire upper bed.

Whether naked, coated or even decorated, no lateral abrasion of the barrels occurs since there is no contact between the bottles of the same bed. There is also no abrasion on the drink since the internal seam of the ring mold remains free and the oblique tightening along the same line 3a, 3b, eliminates any possibility of vibrations and slippage at the points. of contact. A similar result would be obtained with bottles of which the ring mold would be in two parts, the transverse seam which they have then coming very locally to lodge in the material at the level of the contact line 3a without the possibility of subsequent sliding.

We also see that the constitution of the load as the recovery of the successive beds of bottles is carried out practically as on conventional pallets where cardboard trays are used, except that, bed after bed, the bottles are kept spaced by the platforms at each stage of the operation; handling is therefore at least as easy to automate as in conventional solutions according to which stability is obtained by direct contact with the bottles of each bed, and much more than in those which use indirect contact with the interposition of lateral separators such as braces.

FIG. 6 shows, as a variant, bottles 30 placed on a plate 31, the bottom 32 of which carries circular imprints 33 and holding moles 34, 34 ′ arranged in a triangular mesh, which, as we know, has for the disadvantage of somewhat complicating the handling of the bottles, but in return makes it possible to obtain more compact charges.

The general structure of this tray will not be described again in all its details because it is similar to the previous one. But, intended to receive bottles with a "flat bottom (in fact and of course this bottom is very slightly tucked in and has a concavity of the order of a few millimeters), its imprints 33, which are separated from the moles 34, cannot be identical to those of a tray intended to receive bottles with a "pique" bottom. As shown in FIG. 7, they nevertheless retain a very similar shape: each essentially comprises a nipple 35 crowned with a step 36, in the top of which a cutout 37 simply opens; here again the imprint thus forms downwards a cell whose wall comes to bear along a line 33a on the only outer rim of the rim of the bottles of the lower bed, while connecting to a conical wall 38, inclined at 30 °, which is used to guide the necks when installing the intermediate plate. However, the total height H of the nipple is necessarily greater than the depth p of the retracted part 39 of the base of the bottles of the upper bed: for this reason, the annular seats 32a formed by the bottom 32 are connected to the conical wall 38 not directly or by the sole intermediary of a cylindrical wall trimming like the previous case but on the contrary by a groove 40, so that the total height h of the imprint above the bottom is reduced to a value very slightly lower at the depth p of the concavity of the base. To make it more rigid in compression but more flexible in bending relative to the support line 33a, the groove 40 is advantageously provided with a relatively vertical wall 41 and a flat bottom 42 giving it a substantially trapezoidal profile.

When the load is constituted, first placing a first plate on a transport pallet 43, the latter rests there by means of the groove bottoms 42; the bottles of the first bed then come to bear on the seats 32a of the bottom 32: the walls 41 will therefore distribute the entire weight of the stack but their rigidity is sufficient to prevent them from being crushed, which would compromise balance. In the extreme, the pallets could moreover be fitted with appropriate housings.

On the other hand be noted that, in their poses, the pellets of lit'supérieur the bottles are guided not by the 33 footprints, but only by moles separation 34. These are the ^* number three around each bottle but one could if necessary provide six, by doubling the rows 34a by rows 34b.

Of course, during the continuation of the loading, the behavior of the upper plates is identical to that of those described above, their bending bringing the necks of the bottles of the other beds carried on the line 33a, and the bottles again form rigid columns secured horizontally by the intermediate plates, all of the load held in place on the handling pallet by a retractable cover which immobilizes everything during transport.

Claims (12)

1. A plate for forming successive layers of a stack of palettised receptacles having necks, comprising a sheet having indents, each indent forming at its centre on a first surface of the sheet a socket capable of receiving the rim of the neck of receptacles of a lower layer, and at its periphery on the second surface of the sheet a seating capable of receiving the bottom of receptacles of an upper layer, characterised in that towards the centre the cross-section of the indents is close to that of said bottom to bring the plate in contact with the bottom on stacking, the plate being engaged between the rim and the bottom only at the exterior edge (6a) of the lip of said rim, the flange (7a) of the bottom resting on the periphery of the indent but imposing only a minimum elastic deformation thereon.

2. A plate according to claim 1, characterised in that the socket which each indent defines downwardly has an enlarged entry (9, 38) having a slope of at least 20 %.

3. A plate according to claim 2, characterised in that the indent forms on its upper surface a protrusion surrounded by an annular seating (2a, 32a) of which the top comprises an upstanding circular crown (10, 30) of internal diameter corresponding to that of the rim of the lower receptacles, with a central relief which limits this peripheral circular crown to a width less than that of the upper lip of the rim.

4. A plate according to claim 3, characterised in that the central relief is formed by a knob (12) extending slightly at the upper surface.

5. A plate according to claim 3, characterised in that the upstanding crown comprises a rounded nose (11) having a radius of curvature (r) which is at least that of the exterior edge (6a) of the lip.

6. A plate according to claim 5, characterised in that the difference between said radius of curvature and that of the external edge of the lip is about twice the tolerance between the internal diameter of the socket and the exterior diameter of the rim.

7. A plate according to claim 3, characterised in that the annular seating is planar and connected to the protrusion by a low step (14).

8. A plate according to claim 3, characterised in that the protrusion is connected to the annular seating by a groove (40) of substantially trapezoidal cross-section.

9. A plate according to one of claims 3 to 8, characterised in that the circular crown (10, 36) is positioned, relative to the annular seating (2a, 32a) at a height (h) slightly less than that (p) of the corresponding part of the bottom.

10. A plate according to one of the preceding claims, characterised in that the indents are separated by prismatic upstanding members (4, 34).

11. A plate according to claim 10, characterised in that the sides of the upstanding members are indented to form a series of reliefs (17c) separated by partial bearing surfaces (17d) having a pointed end at their upper part.

12. Receptacles, stacked in superposed layers separated from each other by intermediate plates according to one of the preceding claims to be held together by a retractable housing.

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