Method of packaging products

Abstract: A packaging method using a packaging tray that is assembled from a rectangular blank (P) of paper material, which is provided with a first fold line (5) parallel to its longitudinal edges at a distance corresponding to twice the desired height of the tray, a second fold line (6) being provided between said first line and the adjacent longitudinal edge, said fold lines extending substantially along the entire length of the blank, a third fold line (8) being provided parallel to each of the transverse edges at a distance corresponding to the height of the tray, said third fold lines being cut through from the longitudinal edge(s) inwardly up to the adjacent first fold line so as to form transverse cuts (9), in such a way, that the longitudinal side walls may be formed by upward folding about said first fold line and outward and downward folding about said second fold line, whereas the end walls are formed by folding about the third fold lines and flanges of said end walls - which are obtained by said cuts - will be caught between the inner longitudinal side wall seetions and the outerwardly and downwardly folded section of the respective longitudinal side wall. Upon filling the packaging tray is wrapped with and kept in shape by a tubular foil.

Description: The invention relates to a method of packing articles, such as various types of bakery and chocolate products in a substantially rectangular tray-shaped container, wherein the tray is supplied, via a filling station, to a station where the filled tray is wrapped by a tube-shaped, the tray tightly surrounding wrapper of a transparant foil. Such a method is known. Up to now in general use has been made of trays, formed of plastics material. The manufacture of the trays is taking place according to a process, that is performed independent of the packing process. In general the trays are supplied in a continuous flow through a filling station, where the trays are filled with the articles to be packed, upon which the filled trays are passed through a so-called "flowpacker" (vide e.g. EP-A-0142904 and US-A-4203270) that wrappes the filled trays by a tubular foil, with sealed ends. Such trays which are commonly designed as disposable packages result in waste material of a non-decomposable or hardly decomposable type. The invention aims at meeting the increasing objections against such packaging material by providing an alternative packaging tray of decomposable material, the manufacture of which is simple and may be simply integrated in the proper packaging process. In accordance with the invention this aim is achieved by the method defined in claim 1 The envelope of the filled tray is utilized to hold the walls of the tray in the assembled position, avoiding the use of additional fastening means, such as an adhesive or stables. Moreover this allows the tray - after it has been emptied and after the envelope has been completely removed - to be simply flattened into space saving, easily decomposable waste material. Furthermore the blanks for the above described packaging trays may be manufactured in a simple manner and without wastage. In accordance with a practical embodiment the packaging trays are cut from a supply roll in the supply path towards the filling station. It is to be remarked, that it is well-known per se from DE-A-22012641 to fold boxes from blanks and have flanges of the end walls captured between inner and outer longitudinal side wall sections. In this case, however, boxes are involved, whereby the outer longitudinal side wall sections are folded - about the second fold lines - inwardly and locked in this inwardly folded position by means of lips extending from the longitudinal side wall edges, which engage into corresponding slots of the bottom section. Furthermore US-A-3627116 disclosed a packaging container folded from a substantially rectangular blank, which is kept in shape by a tubular envelope without using an adhesive, staples or the like. In this case, however, a quite different type of package is involved , viz. a container having open ends, whereas the blank is provided with fold lines extending in one direction only. Moreover there is no mention of a method, whereby the assembling of the successive packages has been integrated in a continuous packaging process. The invention will hereinafter further described by way of example with reference to the accompanying drawings in which: Fig. 1 is a perspective view of a packing tray according to the invention; fig. 2 is a diagrammatic and perspective view illustrating the process of cutting blanks from a supply roll and folding the latter in successive steps to a flow of packing trays according to the invention; fig. 3 is a plan view of a blank for a packing tray according to the invention; fig. 4 is a perspective view of a detail of a partially folded packing tray. In fig. 1 a packing tray is shown tightly wrapped by an envelope of film material 2 such as cellophane. The packing tray 1 is folded from a substantially rectangular blank of paper material, such as the blanks P shown in fig. 2, which are cut in succession from a supply roll 3. As shown in fig. 3, the blanks P comprise a rectangular piece of paper material, which may have a corrugated structure, with the crests and valleys directed transversely to the longitudinal direction of the blank. A first folding line 5 is provided parallel to each of the longitudinal edges 4 of the blank P, at a distance corresponding to twice the tray height h. A second folding line 6 is impressed mid-way between each of the folding lines 5 and the respective longitudinal edges 4 of the blank. A third folding line 8 is provided parallel to each of the short sides 7 of the blank, at a distance corresponding to the tray height h. These third folding lines 8 have been cut through from the two longitudinal edges 4 inwardly up to the first folding lines 5, so that cuts 9 are formed. The said folding lines and cuts may be provided in the web unrolled from the supply roll by using well-known techniques. For reasons of simplicity the folding lines and cuts are shown provided in the web material while it is still on the roll. Thus blanks P are successively severed from the supply roll 3 by means of a cutting device 10. The folding lines 5, 6 and 8 and the cuts 9 divide the blank P into a tray bottom panel 11, two outer and inner longitudinal side wall panels 12 and 13 respectively, two end wall panels 14 and four end wall flange panels 15. In the diagrammatic view of Fig. 2 the starting material supplied from the supply roll 3 and to be cut into individual blanks is put onto a conveyor line between two lateral guides 16. In the example shown the conveyor line is formed by a central conveyor belt 17, with an additional belt 18 provided on either side of the latter. In a first station indicated at I the blank is still in a completely flat state. In a second station II the folding of the longitudinal side wall panels 12, 13 is effected by folding about the first or inner fold lines 5 (vide the arrow direction). From station II the partly folded tray is transferred - with the (still flat lying) end wall panels 15 supported on the two pusher belts 8, to a third station III. There is an interruption of the central conveyor belt 17 in the third station, which allows the folding of the end wall panels by folding about the third fold lines 8 (vide the arrows in the third station III). From the station III the tray is - now with the end wall flanges 15 supporting in a vertical position on the lateral conveyor belts 18 - transferred onto the continuing central conveyor belt 17 in a fourth station IV. Within the station IV the end wall flanges 15 are folded inwardly (vide the arrow direction) against the outer side of the vertically extending inner longitudinal side wall panels 13, after which the tray is displaced into a fifth station V. In the station V the tray 1 is completed by folding the outer longitudinal side wall panels 12 downwardly. The tray is then - in its completed state-passed on and caught between lateral guide means 19 which keep the outer longitudinal side wall panels 12 in the outwardly and downwardly folded positions. In this state the tray is passed through a filling station (not further shown), where the tray may be filled. In continuation thereof the tray - while still being kept in shape between the continuing guide means 19 - is passed through the so-called "flow-packer" (neither shown), which provides the filled tray with a tight wrapper of cellophane. The laterial guide means 19 are discontinued at a location where the leading end of the tray is engaged by the wrapping tube being formed. In the diagrammatic view of fig. 2 the height of the packaging tray has been, for clarity's sake, shown out of proportion. The blank P shown in fig. 3 is also provided with two pair of additional cuts 21, which extend from the second fold lines 6 inwardly to an extent corresponding with twice the tray height. When folding the longitudinal side wall panels 12, 13 upwardly, these additional cuts allow the forming of portions 22 (vide fig. 4) which extend inwardly from the inner longitudinal side wall panels and may function as a partition to divide the tray into compartments.

Claims: Method of packing articles, such as various types of bakery and chocolate products in a rectangular tray-shaped container, wherein the tray is supplied, via a filling station, to a station where the filled tray is wrapped by a tube-shaped, the tray tightly surrounding wrapper of a transparant foil, characterized in that the packaging tray is assembled - in the supply path towards the filling station - from a rectangular blank of paper material, having a first fold line provided parallel to each of its longitudinal edges at a distance corresponding to twice the desired height of the tray, a second fold line being provided in the middle between each said first line and the adjacent longitudinal edge, said fold lines extending along the entire length of the blank, a third fold line being provided parallel to each of the transverse edges at a distance corresponding to the height of the tray, said third fold lines being cut through from the longitudinal edges inwardly up to the adjacent first fold line so as to form transverse cuts, in such a way, that the longitudinal side walls are formed by upward folding about said first fold lines and outward and downward folding about said second fold lines, whereas the end walls are formed by folding about the third fold lines and flanges of said end walls - which are obtained by said cuts - will be caught between the inner longitudinal side wall sections and the outerwardly and downwardly folded section of the respective longitudinal side wall, the completely folded tray thereafter being moved between lateral guide means towards and through the filling station and further to the wrapping station, said lateral guide means being interrupted at the location where the leading end of the tray is engaged by the wrapper developping in the wrapping station. A method according to claim 1, characterized in that the packaging trays are cut from a supply roll in the supply path towards the filling station.

Inventors: STAATS ANTONIUS PETRUS, STAATS, ANTONIUS PETRUS
Applicants: STAATS ANTONIUS PETRUS, STAATS, ANTONIUS PETRUS
Application year: 1992
Main classification: B65B11
IPC codes: B65B11, B65D77