Storage and/or transit stacking of articles

Abstract: Thermo-formed trays (3) carrying rows of bottles (1) are stacked one upon the other with the tops of the bottles (1) on each tray engaged in channels (15) of the tray (3) above. Each channel (15) is closed at both ends so as to hold its row of bottles (1) tightly against one another in line. The upper-surface (6) of the tray (3) is enclosed on three sides (7 to 9), or all four (7 to 10), by a peripheral wall (5) and is divided into guideways for the rows by ridges (11) to restrict lateral movement of the bottoms of the bottles (1) out of row-alignment. Lateral restraint may be provided without ridges by abutment of the rows of bottles (35 Figures 6 to 8) with one another, and the wall (34) may be configured to the contour of the bottles (35) in their rows. The channels (40 Figure 8) nested on the tops of the rows of bottles (35) below, may run slantwise of the tray (33).

Description: This invention relates to storage and/or transit stacking of bottles or other articles, of the kind in which a plurality of arrays of rows of the articles are stacked one upon the other with each array above the lowermost standing on an upper-surface of an individual tray that itself stands on the tops of the articles of an array immediately beneath it in the stack, and in which the under-surface of the tray is configured for retaining engagement with the tops of the array of articles on which it stands. A method of the above-specified kind for stacking bottles, is known from DE-A-3 714 352. In this known method, the trays as loaded with arrays of bottles are stacked one upon the other with the bottom tray resting on a pallet and each of the others standing on the tops of the bottles of the array beneath. A specially adapted lid is placed on the tops of the bottles of the uppermost array to complete the stack in preparation for bonding the stack together, and to the pallet, using straps. With the method of DE-A-3 714 352, the bottoms of the bottles of each array are engaged in respective recesses or sockets configured in the upper-surface of their tray, and their tops are engaged similarly in respective recesses or sockets of the tray or lid immediately above in the stack. Although the bottles are in this way held firmly in their rows, they are necessarily spaced apart from one another, with consequent loss of achievable packing density, by the need to accommodate individual sockets for each bottle on the upper-surface of their tray. In addition, loading of each tray of the stack requires accurate location of the bottom of each bottle in its individual socket of the tray upper-surface, and then, when the tray is full, accurate handling of the next tray (or ultimately the lid) to align the sockets of its under-surface with the tops of the loaded bottles to ensure that positive engagement by each individually is achieved. Moreover, on unloading the stack, difficulty is likely to be experienced with achieving efficient and easy removal of first the lid, and then each successively-emptied tray, from the tops of the bottles, owing to the resistance met in breaking the engagement with their individual sockets; the resistance may readily vary from one bottle to another across the lid or tray causing it to bend or even be damaged as it is removed. Furthermore, the bottles have to be lifted from the sockets in which they stand, and so where the bottles of the stack are to be supplied for filling or other mechanised handling, advantage cannot be taken of conventional unloading mechanisms that sweep bottles in bulk sideways onto a moving conveyor. It is an object of the present invention to provide a method of stacking bottles or other articles, of the said above-specified kind, and a tray for use in such method, that are of advantage in one or more of the above aspects over the known method and tray. According to the present invention a method of stacking bottles or other articles, of the said above-specified kind is characterised in that the tops of the articles are engaged with the tray under-surface within elongate channels individual to the rows, and that the engagement of the tops within the channels tends to restrain movement of the articles laterally out of their respective rows. The use of elongate channels in the under-surface of the tray for engagement by the tops of the articles, has been found to offer significant advantages over what is known from DE-A-3 714 352. In particular, the channels provide a simple and economic way of establishing the articles in rows and providing at least partial restraint against lateral movement from those rows. The restraint obtainable in this regard has been found to be generally sufficient to avoid the need to establish individual engagement with each article, on the upper-surface of the tray. The upper-surface of the tray may in the latter respect be configured to divide that surface into parallel guideways for separating the rows of articles from one another; these guideways may be defined between ridges that are upstanding from the upper-surface of the tray. The articles may in these circumstances be at least partly restrained from individual movement longitudinally of the rows by abutment with one another in the rows. However, separation of the rows from one another using ridges or other means on the upper-surface of the trays, is not generally necessary, and the articles may in this case be restrained from individual movement laterally, and also longitudinally, of the rows by abutment with one another. Even where row-separation is utilised, the achievable packing density is significantly increased over what can be achieved with what is known from DE-A-3 714 352, and use of a sweeping mechanism for mechanised unloading is possible. Engagement of the tops of the articles with channels in the tray under-surface, in accordance with the present invention, facilitates both loading and unloading of the stack. As compared with use of individual sockets in the tray under-surface of the known method, the use of channels makes alignment with the tops of the articles simpler and more readily brought about for loading, and reduces the likelihood of resistance and other difficulties in removing the trays during unloading. The channels may have closed ends and this may assist during loading in that pushing down of the tray onto the tops of the articles beneath, can serve to urge them together in their respective rows. The present invention is also concerned in a further aspect with the provision of a form of tray for use in a method of the said above-specified kind, namely in retaining bottles or other articles in an array of rows of a plurality of such arrays stacked one upon the other for storage and/or transit of said articles, where such tray is of the specific form in which an upper-surface of the tray is adapted to receive the bottoms of the articles standing in their rows, and the under-surface is configured to be engaged by the tops of the articles of the array immediately below it in the stack. According to this further aspect of the present invention, a tray of the specific form referred to in the preceding paragraph is characterised in that the under-surface of the tray is configured to define a plurality of elongate channels for engagement by the tops of the articles of individual rows such as to tend to restrain movement of these articles laterally out of their rows. The upper-surface of the tray may be at least partly enclosed by a rim or wall upstanding from that surface, and may be configured to define (for example, by ridges upstanding from that surface) a plurality of spaced parallel guideways for receiving the bottoms of the articles of respective rows. The channels may be in register with the guideways respectively. The method and form of tray of the present invention is of especial advantage as compared with the method and tray of DE-A-3 714 352, in the stacking of glass bottles, and in particular glass bottle flasks, for secure transportation without damage. Using the method and form of tray of the invention it is possible to stack a large number of the bottles or flasks together tightly and achieve a high packing density. Methods of stacking bottles and forms of tray for use therein, both in accordance with the present invention, will now be described, by way of example, with reference to the accompanying drawings, in which: Figure 1 shows in front elevation, part of a stack of bottle flasks, the stack being constructed, and using identical trays of a form, according to the invention; Figure 2 is an enlarged side elevation of a portion of the stack of Figure 1, with one of the trays of the stack shown in cross-section; Figure 3 is a top plan view of one of the trays of the stack, showing it part loaded with flasks; Figure 4 is an underneath plan view of a portion of the tray of Figure 3; Figure 5 is a perspective view of a modified form of tray according to the present invention; Figure 6 is a top plan view of a second form of tray according to the present invention, for use in the stacking of bottles of circular cross-section and shown part loaded with such bottles; Figure 7 shows the tray of Figure 6 in side elevation and partly in section, the section being taken on the line VII-VII of Figure 6 and illustrating use of the tray in the stack; and Figure 8 is a top plan view corresponding to that of Figure 6, illustrating a modification of the tray of Figures 6 and 7. Referring to Figure 1, more than one thousand identical glass flasks 1 are loaded together on a wooden pallet 2 to stand upright with one another in five rectangular arrays of eleven rows each, that are stacked one upon the other. Six identical moulded-sheet trays 3 are included in the stack to locate and retain the flasks 1 together in the five arrays. A tray 3 of the first, bottom array of the stack stands directly on the pallet 2 with the flasks 1 of that array standing upright on the tray 3, and with a tray 3 of the second array standing on the tops of those flasks 1. The flasks 1 of the second array similarly stand upright in their tray 3, and a third tray 3 of the next, third array stands on them. This stacking arrangement in which each successive array of flasks 1 stands in its individual tray 3 on the array beneath, is repeated for the third to fifth arrays. Five trays 3 are used for the five arrays, and the sixth tray 3 stands on the tops of the flasks 1 in the fifth, uppermost array, to top off the stack. The whole, including the pallet 2, is encased in shrink-film (not shown) to hold the stack tightly together as one for secure storage and/or transit. Referring now also to Figures 2 to 4, each tray 3 has a peripheral skirt 4 that is extended into an upstanding wall or rim 5 around the upper-surface 6 (Figure 3) of the tray 3 on three of its four sides. The upper-surface 6 is in this respect bounded by the rim 5 along one long side 7 and across the two shorter sides 8 and 9 of the tray 3, and is flat to the other long side 10 except for parallel ridges 11 and troughs 12. The ridges 11, which together with the troughs 12 run out across the tray-width towards the side 10, serve in conjunction with the rim 5 at the sides 8 and 9, to divide the upper-surface 6 into eleven parallel guideways 13 for receiving the rows of flasks 1. The flasks 1 of each row stand in their respective guideway 13 packed tightly and nesting together along the full row-length with the first flask 1 in the row abutting the rim 5 at the side 7 and the last standing adjacent the flat side 10. The bottom of each flask 1 stands firmly on the upper-surface 6 straddling the troughs 12 and being restrained from lateral movement out of row-alignment by the ridges 11 that separate the guideways 13 from one another. Each tray 3 is configured by the troughs 12 of its upper-surface 6, to present in its under-surface 14 (Figure 4) eleven channels 15 that extend in central register respectively with the eleven guideways 13 above. Each channel 15 is closed up at its two ends 16, and its sidewalls 17 flare down to a minimum width which is substantially the same as the diameter of the flask open-mouth top. The flaring of the side-walls 17 assists with the nesting of the tray 3 down on the tops of the flasks 1 below. More particularly, as the tray 3 is pushed down onto the array below, so the tops of the flasks 1 of each row of that array are each guided positively for firm and full reception into an individual one of the channels 15. Any tendency for the flasks 1 to move laterally out of row alignment is positively resisted by the firm hold on their tops within the relevant channel 15. Similar restraint against movement of the row of flasks 1 longitudinally of the row, is achieved by the relationship of the length of the channel 15 to the row length, and the rounding down of the channel ends 16. These are such that the tops of all the flasks 1 in the row are accommodated in the channel 15, only if those flasks 1 are closed up hard on one another throughout the row. Thus as the tray 3 above is pushed down onto the tops of each row of flasks 1, so the flasks 1 of that row are urged hard onto one another to be held in that condition. The flasks 1 of each individual array of rows in the stack are afforded lateral location and individual support by the tray 3 on which they stand. The fit of the flasks 1 is not in this case (illustrated in Figures 2 and 3) tight and so allows for a measure of variation in width of flask 1 loaded on the tray 3. Tighter restraint is provided by the engagement or nesting of the tops of the flasks 1 within the channels 15 of the tray 3 above. This engagement constrains the flasks 1 to tight row-alignment and abutment with one another onto the rim 5 at the side 7. Although the bottoms of the flasks 1 may not be a tight fit within the guideways 13, the fit is close enough to ensure that each flask 1 is prevented by the ridges 11 and rim 5 at the sides 8 and 9, from moving laterally to an extent that would be sufficient to bring about disengagement of the tops from the channels 15. The absence of the rim 5 along the side 10 of the tray 3 facilitates unloading of the flasks 1 onto a conveyor, using a sweeping mechanism which simply draws the whole array of flasks 1 from the tray 3 onto the conveyor across the side 10. Where, however, a lifting mechanism is to be used instead of a sweeping mechanism, for unloading the flasks 1, the tray 3 can be modified to continue the upstanding rim 5 along the side 10. With this modification, a greater degree of restraint against possible longitudinal movement of the rows of flasks 1 is afforded, but it has been found that the absence of the upstanding rim along the side 10 is in general acceptable. Any added restraint required can in any event be afforded by the encasing shrink-film alone, or by the addition of a sheet (for example, of card or other board, or plastics material) butted against the sides 10 of the stacked trays 3 and held in place by the shrink-film encasing. The tray 3 is thermo-formed from a sheet of high-impact polystyrene. The sheet, which for example, may have a thickness of 2 mm, is thermo-formed over a mould that conforms positively, with allowance for sheet thickness, to the configuration of the under-surface 14 required. A modified form of tray that is thermo-formed over a mould conforming positively to its upper-surface, is illustrated in Figure 5, and will now be described. Referring to Figure 5, the upper-surface 20 of the modified form of tray, like the upper-surface 6 of the tray 3 described above, is divided into parallel guideways 21 for receiving the rows of flasks. However, in this case the ridges 22 (only one shown) which separate the guideways 21 from one another, are lower than the ridges 11, and the wall or rim 23 of the tray where it bounds the shorter sides 24 (only one shown) is sloping. In the latter respect, the rim 23 at its full height along one long side 25 of the rectangular tray, is higher than the rim 5 of the tray 3, but slopes down progressively along the shorter sides 24 to run out to the other long side 26. The channels in the under-surface 27 of the tray, required to receive and constrain the tops of the flasks, are configured by troughs 28 in the upper-surface 20. The troughs 28 are steeper-sided than the corresponding troughs 12 of the tray 3 in order that the channels provide tighter constraint on the engaged flask-tops. The walls of these channels are in this respect also strengthened by the provision of ribs 29 on the under-surface 27. The ribs 29 are configured by grooves 30 in the upper-surface 20, which run transversely of the ridges 22 from each wall-defining trough 28 to the next. The tray of Figure 5, like the tray 3 described above with reference to Figures 1 to 4, is for use where flasks are to be unloaded using a sweeping mechanism, such mechanism being used to discharge the flasks from the guideways 21 across the side 26. If a lifting mechanism is to be used instead, then the upstanding wall or rim 23 of the tray may be extended from the side 25 along the other three sides 24 and 26 at the full height, to afford greater restraint on the flasks. The trays described above are used in the stacked storage and/or transit of bottles in the form of flasks, however, the principles embodied in the trays and their use are equally applicable to the provision of trays adapted to the stacked storage and/or transit of other forms of bottle. A form of tray for use in the stacking of bottles of circular cross-section, is illustrated in Figures 6 and 7, and will now be described. The bottles are loaded on this tray in staggered rows with each bottle within the array abutting not only the adjacent bottles of its row, but also the adjacent bottles of the two adjoining rows. Referring to Figures 6 and 7, the upper-surface 32 of the rectangular tray 33 in this case has an upstanding peripheral wall 34 that is configured to the bounding contour of the array of bottles 35 in their staggered rows. The peripheral wall 34 confines the bottoms of the bottles 35 to remain in their respective rows on the surface 32. The location of the bottles 35 in the staggered rows during loading on the surface 32, and their retention in that array, is in this respect defined and enhanced by the wall-contouring. The upper-surface 32 is flat apart from troughs 36 that run lengthwise of the rows and configure the under-surface 37 to present channels 38 in central register respectively, with the rows above. Each channel 38 is closed at both, rounded ends and receives the tops of the bottles of a respective row of bottles 35 of the tray beneath in the stack; the walls of the channels 38 are flared slightly to ease bottle-top entry. The channel-length and -width are just sufficient to accommodate the tops of the bottles 35 of the respective row. Thus, not only are the bottoms of the bottles 35 in each row of the stack held firmly against movement in any direction by the confinement of the array exercised by the surrounding wall 34 of the tray on which those bottles 35 stand, but the tops are also held against movement laterally and longitudinally of the row by their nesting engagement in the channel 38 of the tray above in the stack. The abutting and closely-staggered formation of the bottles 35 provided by the rectangular tray 33, allows diagonal- or slanting-row patterns to be identified in the array, as well as rows running lengthwise or widthwise. The channels 38 in the under-surface 37 may run parallel to any such pattern of rows, and the tray 33 may be modified in this respect as illustrated in Figure 8, where a diagonal or slanting disposition of troughs 39 in the upper-surface 32 presents slanting channels, indicated by broken lines 40, in the under-surface. The wall 34 need not be configured to conform to the outer contour of the array of bottles 35, but may be straight. Furthermore, the wall 34, rather than completely enclosing the upper-surface 32 of the tray 33, may be modified to extend along just three sides so as to allow for the bottles 35 to be swept from the tray 33 during unloading; clearly, the wall 34 is in this case desirably straight along at least the two sides parallel to the direction of sweeping. Although the flasks and other bottles referred to above, are all empty and without closure caps, the described trays are readily adaptable also to the stacked storage and/or transit of the flasks and other bottles when filled and capped.

Claims: A method of stacking bottles or other articles, in which a plurality of arrays of rows of the articles (1; 35) are stacked one upon the other with each array above the lowermost standing on an upper-surface of an individual tray (3; 33) that itself stands on the tops of the articles (1; 35) of an array immediately beneath it in the stack, and in which the under-surface (14; 27; 37) of the tray (3; 33) is configured for retaining engagement with the tops of the array of articles (1; 35) on which it stands, characterised in that the tops of the articles (1; 35) are engaged with the tray under-surface (14; 27) within elongate channels (15; 38) individual to the rows, and that the engagement of the tops within the channels (15; 38) tends to restrain movement of the articles (1; 35) laterally out of their respective rows. A method according to Claim 1 wherein the channels (15; 38) have closed ends such that pushing down of the tray (3; 33) upon the rows of articles (1; 35) beneath, urges those articles (1; 35) to close up together in their respective rows. A method according to Claim 1 or Claim 2 wherein the upper-surface (6; 20) of the tray (3) is configured to divide that surface (6; 20) into parallel guideways (13; 21) for separating the rows of the respective array from one another. A method according to Claim 3 wherein the guideways (13; 21) are defined between ridges (11; 22) that are upstanding from the upper-surface (6; 20) of the tray (3). A method according to any one of Claims 1 to 4 wherein the articles (1; 35) are at least partly restrained from individual movement longitudinally of the rows by abutment with one another within the rows. A method according to Claim 1 or Claim 2 wherein the articles (35) are at least partly restrained from individual movement both laterally and longitudinally of the rows by abutment with one another. A tray for use in retaining bottles or other articles in an array of rows of a plurality of such arrays stacked one upon the other for storage and/or transit of said articles, in which an upper-surface (6; 20; 32) of the tray (3; 33) is adapted to receive the bottoms of the articles (1; 35) standing in their rows, and the under-surface (14; 27; 37) is configured to be engaged by the tops of the articles (1; 35) of the array immediately below it in the stack, characterised in that the under-surface (14; 27; 37) of the tray (3; 33) is configured to define a plurality of elongate channels (15; 38) for engagement by the tops of the articles (1; 35) of individual rows such as to tend to restrain movement of these articles (1; 35) laterally out of their rows. A tray according to Claim 7 wherein each channel (15; 38) has closed ends such that engagement of the tops of the articles (1; 35) of the respective row with that channel (15; 38) restrains them from movement together longitudinally of that row. A tray according to Claim 7 or Claim 8 wherein the upper-surface (6; 20) of the tray (3) is configured to define a plurality of spaced parallel guideways (13; 21) each of which is for receiving the bottoms of the articles (1) of a respective one of the rows, and the guideways (13; 21) are respectively in register with the channels (15) defined in the under-surface (14; 27) of the tray (3). A tray according to Claim 9 wherein the guideways (13; 21) are defined between ridges (11; 22) that are upstanding from the upper-surface (6; 20) of the tray (3). A tray according to any one of Claims 7 to 10 wherein the upper-surface (6; 20; 32) of the tray (3; 20; 33) has an upstanding wall (5; 23; 34) that extends around all or a substantial part of the periphery of that surface (6; 20; 32) for restraining the articles (1; 35) from movement from the upper-surface (6; 20; 32) laterally of the rows. A tray according to Claim 11 wherein the wall (34) is at least partly configured to conform to the contour of the articles (35) in their rows. A tray according to any one of Claims 7 to 12 wherein ribs (29) extend between the channels to strengthen the channel walls. A tray according to Claim 13 wherein the channels are configured by troughs (28) in the upper-surface (20), and the ribs (29) are configured as grooves (30) running between the troughs (28) in that surface (20) A tray according to any one of Claims 7 to 14 of thermo-formed plastics construction.

Inventors: EMBLETON MICHAEL CHRISTOPHER, PITT JEFFREY GRAHAM, EMBLETON, MICHAEL CHRISTOPHER, PITT, JEFFREY GRAHAM
Applicants: FORMOLD LTD, FORMOLD LIMITED
Application year: 1992
Main classification: B65G57
IPC codes: B65D71