Modular tray for separating yarn spools

Abstract: The invention concerns a tray (1) of a plastic material for separating yarn spools disposed in layers on a pallet. The tray (10) is formed by a plurality of modular members (10) connected to each other, each member comprising a base (11) from which protrudes a series of elements (12, 13, 14) for the engagement with at least one spool (20) of yarn, said members (10) being integrally formed with said base (11), and being laterally provided with means (6) for the coupling with adjacent modular members (10).

Description: The present invention is concerned with separating elements to be placed between adjacent tiers of yarn spools stacked onto a pallet, such elements being also known as trays or layer separators. For shipping and stocking yarn spools, the spools are disposed onto a pallet by automatic machines and then the assembly is wrapped with a film of heat-shrinkable plastic material or packaged in cardboard boxes. Other automatic machinery is later used to pick up the yarn spools from the pallets. In order to arrange the spools in stacked layers or tiers, separators in form of trays are inserted between the spools of two adjacent tiers, with such trays also performing a lateral restraining function and making easier the centering of the spools by the packaging machine and their subsequent picking up. To this aim there have been used separating trays made of cardboard sheets provided with holes in correspondence of which plastic truncated cones for centering the spools are inserted and secured. This solution has the drawback of requiring a manual positioning of the cones into the centering and blocking holes, and moreover such cardboard trays are not reusable since they are subjected to breaking and damages. Separating trays have also been manufactured of plastic materials and forming the spool centering cones integral with the tray body. Although these trays are stronger and longer lasting, as well as adapted to be reused, nevertheless they exhibit several drawbacks. The cost of the mold is high due to the large dimensions of the article to be molded. Moreover, when trays with different configurations are requested, e.g. because of different diameters of the spools to be stacked or different spacings provided between the cones, several molds are to be manufactured, each with a corresponding high cost. Moreover, any breakage of a tray portion causes a significant waste of material since the whole tray has to be discarded. To overcame these shortcomings there has been suggested to make stronger trays, that is with an increased thickness and a larger amount of plastic material for each tray, but this solution brings about a further increase of the costs and of the weight that renders the assembled spool packages as well as the packages of trays difficult to be moved. A further drawback of the known plastic material trays comes from the fact that the upstanding cones all protrude at the same locations on each tray, thus preventing an effective superimposing of the stacked trays, typically during the encasing step when a machine picks up single trays from a stack and place them between the tiers of the yarn spools. An unstable balance of the spools can be of prejudice for automated procedures, requiring manual interventions and as a general rule by increasing the cost for positioning and packaging the spools on the pallets. Examples of trays formed of cardboard are illustrated in US-A-4 141 447 (with cut-outs folded upright for supporting the spools), in EP-A-465 815, and in US-A-4482051 Plastic material trays are disclosed for example in EP-A-229 392, EP-A-194 405, US-A-4 142 634, US-A-4 042 108, EP-A-514 985. GB-A-1 544 983 discloses modular component parts for yarn spools packaging with an associated connecting system in the packaging of yarn spools. US-A-5 390 789 refers to a plastic material tray for separating stacked layers of yarn wound on spools disposed on a pallet, comprising a substantially flat base surface, provided on both faces with protruding portions for engaging said yarn spools of two adjacent layers. FR 1593225 refers to supports for yarn spools having a parallelepiped body made of synthetic material. The lateral walls of aid supports are provided with centering means of triangular section which avoid any clearance between the supports when in the package. A central cylindrical locator is also provided for the engagement of the yarn bobbins. EP 0 306 074 refers to an assembly made of a plurality of layers for storing, shipping and displaying polyethylene bottles. Each layer of said assembly is obtained by joining together a plurality of trays already filled either with empty or plenty bottles, depending on the step reached in the manufacturing process. The joining of the trays filled with the corresponding bottles is achieved by means of interlocking means and, additionally, by strips of releasable glue provided on the lateral surface of said trays, said glue being strong enough to resist the horizontal and vertical acceleration forces during transportation, and weak enough to allow separation of the trays without damage to the trays themselves. Each of the trays is further provided with sections and recesses for holding the bottom and the top of the bottles. It is an object of the present invention to overcome the above illustrated limitations and drawbacks of the prior art devices. This object of the present invention ia accomplished through a separating tray for yarn spools having the characteristics recited in claim 1. Additional objects of the present invention are obtained through the features recited in the dependent claims. The modular tray according to the invention has a low manufacturing cost since the size of the mold is small and each of the modular members requires a small amount of plastic material. Namely, on one hand the damaging of a tray portion can be overcome by replacing only the corresponding modular tray member, and on the other hand breakages are less frequent due to the stiffening caused by the modular construction and since the trays can be carried or handled as components of reduced dimensions. Moreover the tray according to the invention is ecologically convenient since it reduces the amount of plastic wastes. Moreover, the trays formed by means of the modular members in accordance with the invention exactly fit over each other thus allowing for an optimum stacking thereof. The modest additional cost for assembling the trays according to the invention is largely compensated by the above illustrated economical and practical advantages, to which it is to be added the further consideration that such assembling is extremely simple and usually takes place in countries that are quite far away from the trays supply sources and where the labour cost is low. Further characteristics and advantages of the invention will become evident from the following description of preferred but not limiting embodiments thereof illustrated as non limiting examples in the attached drawings, in which: Fig. 1 is a plan view of a separating tray realized in accordance with the present invention; Fig. 2 is an enlarged view illustrating a preferred embodiment of a modular member forming the tray shown in Fig. 1; Fig. 3 is a perspective view of the modular member shown in Fig. 2; Fig. 4 is a partial cross-section view along line IV-IV of Fig. 2; Fig. 5 is a plan view of another tray according to the invention to be used at the bottom or at the top of a pallet. With reference to Fig. 1, a separating tray or separator 1 for tiers of yarn spools is formed of a plastic material and provides a substantially flat or planar base surface from which extend projections 2 for engaging the yarn spools. Preferably the base surface of the tray 1 is provided with lightening openings and more precisely, as shown in Fig. 2, with a plurality of openings 3 formed as sectors of a circle concentrically disposed about each engagement portion 2, so as to define spokes 4. Additional openings 5 are moreover provided in the surface of base near the corners thereof. According to the invention, the separating tray 1 is formed by a plurality of smaller tray members 10 assembled together, equal to each other in the illustrated embodiment, and laterally provided with means 6 adapted to allow a (non permanent) coupling or connection between adjacent tray members 10 as will be illustrated with more details in the following. Each of the tray members 10, illustrated with more details in Figs. 2, 3 and 4, comprises a substantially flat base 11 provided with an orthogonal rim or flange 18 extending along the entire periphery of the member 10, on both faces, and protruding means 2 for engaging the yarn spools. More precisely, on a face of the tray member 10 there are provided a standing or protruding cylindrical portion 12 adapted to fit the inner space of the core (see Fig. 4) of a yarn spool, and three portions 13, located inside the cylindrical portion and projecting therefrom, adapted to make easier the spool insertion. In the embodiment illustrated in the Figures, such elements are realized as projections with an angular extension smaller than 45° and offset by 120° in respect of each other. Of course it is possible to devise configurations that are different from those illustrated, e.g. with more than three projections, and with an offset of 90° from each other. As it is shown in the partial cross-section view of Fig. 4, on the other face of the tray member 10 there are formed three further portions 14 protruding therefrom (only two visible in Fig. 4), with a construction similar to that of the projections 13, and adapted to facilitate the insertion of a spool. Also the projections 14 are offset by 120° from each other and they are further offset with respect to the projections 13 so that when the members 10 are stacked one over the other, the projections 14 occupy the spaces between pairs of adjacent projections 13 of the underlying member, thus reducing the overall size of a stack of members 10. Advantageously the tray members 10 have a rectangural or square shape, however it falls within the scope of the invention to realize tray members having any desired polygonal shape, either regular or unregular, as well as to form the tray 1 by coupling together tray members 10 having shapes different from each other. Along the peripheral flanges 18 of each of said tray members 10 there are provided pairs of elements 6 formed as recesses for joining together two adjacent elements by means of elastic clips 19. In the embodiment illustrated in Fig. 4, such clips are formed as elastic components of a plastic material having a W shaped cross-sections, adapted to engage and fasten together two tray members located side by side. Of course other different configurations and arrangements of the engaging means can be used for accomplishing the function of the illustrated engaging means and clips. The corners of the base 11 are preferably beveled so as to form a 45° chamfer for facilitating the assembly. Near the chamfers there are formed openings 5 having a generally trapezoidal shape with an arcuated longer base. An annular groove 9 is formed around the cylinder 12, this groove being provided only on that face of the tray member on which the yarn spool 20 rests, and being useful to protect the end or "tail" of the yarn wound on the spool. The trays located at the top and the bottom of the pallet require projections on one face only, with the other face being preferably smooth for a good wrapping of the plastic material or of the packaging cardboard box. To obtain such end tray members, the projections 14 extending downwards are to be eliminated for the top tray member, and the projections 13 and the cylinder 12 are to be eliminated in the bottom tray member. This can be accomplished either by cutting the unnecessary parts, or by locating suitable inserts in the mold and molding dedicated top and bottom trays, respectively. In the illustrated embodiment, the members 10 forming a tray comprise engagement means for a single spool on each face, and the illustrated tray is for a tier of six spools. This is not to be understood as a limitation since according to the invention engagement elements for two or more spools can be formed on each face of a tray member. Further the tray members can have different sizes and typologies, for example incorporating means adapted to engage two spools on each face and means adapted to engage a single spool for each face such as those illustrated in the Figures. Moreover Fig. 5 illustrates two additional alternate embodiments of the invention indicated by 10' and 10''. In accordance with a first embodiment the tray member 10' is not provides with openings 3 and 5 and the four corners are at 90°, whereas according to another embodiment of the invention the tray member 10'' does not provide openings 3 and 5, and has three 90° corners and one 45° beveled corner. The above disclosed tray member 10' and 10'' not provided with openings 3 and 5 can advantageously be used in assembling separating trays to be positioned at the bottom and the top of the pallet, thus preventing the dust from entering the package. More particularly, as shown in Fig. 5, when assembling the tray members to be positioned at the top and the bottom of the pallet, four tray members 10'' - of the type having a single chamfer - will be disposed at the four external corners of the whole separating tray whereas two tray members 10' - of the type having four 90° corners - will be used for the remaining (inner) members. This way the four 45° beveled corners will be located at the outer corners of the package to make easier the wrapping by the heat-shrinkable plastic material or by a cardboard envelope without the risk that sharp corners damage the film or the cardboard box.

Claims: A plastic material tray (1) for separating stacked layers of yarn wound on spools (20) disposed on a pallet, comprising a flat base (11), provided on both faces with protruding portions (2) for engaging said yarn spools (20) of two adjacent layers, said protruding portions comprising a series of elements (12, 13, 14) adapted to engage at least one yarn spool (20) on both faces of said tray (1), said elements (12,13, 14) being integrally formed with said base (11) of the tray (1), characterized in that said tray (1) comprises a plurality of modular members (10) fastened together, each having said protruding portions (2) on each face, and in that each of said modular members (10) is laterally provided with recesses (6) whereby two adjacent modular members (10) are fastened by means of elastic clips (19) having a W shaped cross-section. A tray as claimed in claim 1, characterized in that each of said modular members (10) is provided with a flange (18) extending orthogonally to said base (11) and along the whole periphery of the member (10) on both faces thereof. A tray as claimed in claim 1 or 2, characterized in that all the modular members (10) forming said tray (1) are equal. A tray as claimed in claim 3, characterized in that each of said modular members (10) has a rectangular or square shape with at least three corners beveled at 45°. A tray as claimed in claim 1 or 2 having a square or rectangular shape, characterized in that it comprises a combination of a plurality of inner modular members (10) each having a square or rectangular shape with 90° corners and four modular members (10) positioned at the respective corners of said tray, each of said four modular members (10) having a square or rectangular shape with three 90° corners and one outer corner beveled at 45°, whereby said layer separator shows the four outer corners beveled at 45°. A tray as claimed in claim 1 or 2, characterized in that the base surface (11) of said modular members (10) is provided with lightening openings (3) formed as sectors of a circle concentrically disposed about each engagement portion (2), so as to define a series of spokes (4). A tray as claimed in claim 1 or 2, characterized in that said protruding portions comprise a cylindrical portion (12) and three projections (13) offset by 120° in respect of each other, located inside said cylindrical portion (12) and protruding therefrom, and adapted to facilitate the insertion of a spool. A tray as claimed in claim 1 or 2, characterized in that said protruding portions comprise three projections (14) protruding from the base of the tray offset by 120° in respect of each other. A tray as claimed in claims 7 and 8, characterized in that the projections (13) on a face are offset with respect of those on the opposed face of the modular member (10), so as to reduce the size of a stack of said modular members (10). A tray as claimed in claim 9, characterized in that for each of said modular members (10) an annular groove (9) is formed on a face of said base (11), around said projections (13) for protecting the end of the yarn wound on said spools.

Inventors: FACCIORUSSO CLAUDIO, LOVISOLO PIERO, SALMOIRAGHI SANDRO, FACCIORUSSO, CLAUDIO, LOVISOLO, PIERO, SALMOIRAGHI, SANDRO
Applicants: ALUMETAL AG
Application year: 1997
Main classification: B65D71
IPC codes: B65D67, B65D21, B65D71