EP0958134A1

EP0958134A1 - A box erection device

Info

Publication number: EP0958134A1
Application number: EP96935731A
Authority: EP
Inventors: Bo Arne Nilsson; Sivertz Lundh
Original assignee: Munksjo Forpackningar AB
Current assignee: Munksjo Forpackningar AB
Priority date: 1995-10-19
Filing date: 1996-10-18
Publication date: 1999-11-24
Also published as: SE9503680L; SE505145C2; SE9503680D0; AU7354496A; WO1997014552A1

Abstract

The present invention concerns an apparatus for erecting boxes having folded corners. The apparatus comprises pivotable units for erection of the end and side walls of the box. The invention also concerns corner folding devices comprising erecting means, folding means and fold-over means. The erection means are operative to fold a corner panel of the box into an upright position. The folding means thereafter folds an upper part of said corner panel over the fold-over means. The apparatus likewise comprises means retaining the box corner panels in the inwards folded position while erecting the side and end walls of the box.

Description

A BOX ERECTION DEVICE

The present invention relates to an apparatus for erection of boxes having folded corners. More specifically, the invention relates to an apparatus for erection of boxes that are made from a one-piece box blank sheet. Preferably, the invention relates to an apparatus of erection of boxes made from one single material but also boxes madε from composite materials may be erected by means of an apparatus in accordance with the present invention. Boxes of various kinds are used in many fields in order to facilitate handling and packing of goods and articles. In addition, many various kinds of boxes are available that are adapted to suit various conditions and contents. For certain purposes it is of interest to have boxes that are not closed, i.e. boxes that are open upwards and have no top but yet are stable and strong enough to be stacked one on top of the other. This is the case for instance in boxes designed to contain fruit and vegetables. Boxes of this kind are formed with folded corners, which enhances the box stability generally and the corner stability specifically. Boxes of this type are known from e.g. SE93/00377.

The box described in SE93/00377 is manufactured from one single box blank sheet, which sheet is illustrated in Fig 1 herein. When this box is to be erected, the corner panels 4 projecting from the end walls 3 are initially folded inwards, towards the end walls along fold lines 20 so as to form an essentially right angle with the plane of the box blank sheet. The end walls are then folded along fold lines 23 into an upright position in which they extend essentially perpendicularly to the box bottom panel 1. Subsequently, also the side walls 2 erected along fold lines 22 and flaps 11 are inserted into slits or slots 12 formed in corner panel parts 4b that are contiguous with the end walls. The flaps 11 are then folded upwards, whereby the side walls become interlocked with the corner panels and thus with the end walls. The parts 4a of the corner panels 4 that are spaced from the end walls 3 are then folded towards the end walls along fold lines 21. These panel parts 4a are secured to the end walls by engagement of flaps 13 formed in said panels in slits or slots 14 formed in the end walls, whereby also the flaps 11 will be fixed in their erected, interlocking positions. Owing to the resulting folded, triangular corners a stable box having excellent stacking properties, thus is obtained.

However, the box described above has hitherto been folded and erected manually, which is time-consuming and in most cases an expensive method. In addition, the monotony of the work is hazardous inasmuch as it may cause wear-induced injuries in the personnel employed in erecting the boxes. Consequently, one object of the present invention is to provide an apparatus by means of which boxes having folded corners may be erected and formed from a box blank sheet generally and more specifically boxes of the type described in Patent Specification SE93/00377. The object of the invention is achieved by means of an apparatus defined in claim 1.

The present invention concerns an apparatus for erection of boxes having folded corners. The apparatus comprises pivotable units for erection of the end and side walls of the box. In addition, the inventive apparatus comprises corner folding devices comprising erecting means, folding means and fold-over means. The erecting means are operative to fold a corner panel of the box blank sheet into an upright position. The fold- over means then folds an upper part of said corner panel on top of the first folding means. In addition, the apparatus comprises retaining means for maintaining the box corner panels in the folded position during the erection of the end and side walls of the box. In addition, the apparatus may be provided with means for fastening the end and the side walls of the box to one another. This may be effected by inserting flaps into slits or slots formed for that purpose, or by stapling or gluing.

The invention will be described more thoroughly in the following for exemplifying purposes by means of one embodiment and modifications thereof. The description will be made with reference to the accompanying drawings, wherein:

Fig 1. illustrates a box blank sheet from which a box may be formed by means of an apparatus in accordance with the present invention; and

Fig 2. is a schematic view showing the apparatus in accordance with the invention in a view from above.

A box erection apparatus in accordance with the invention designed to fold box blank sheets configured as illustrated in Fig 1, is shown in Fig 2. The apparatus comprises a centrally disposed plunger device 101 which preferably is equipped with suction cups 102. In operation of the apparatus the plunger device 101 is extended against a supply of box blank sheets, the suction cups 102 adhering to the part 1 of the box blank sheet that corresponds to the box bottom panel. In accordance with one embodiment, the extendible plunger device 101 is equipped with four suction cups 102 positioned in a rectangular pattern and preferably made from some rubber material in the interior of which vacuum pressure may build up with the aid of a pump connected to the cups, causing the cups to adhere to the sheet by suction. However, it is likewise possible to use a different number of suction cups and to position them in another pattern. It is likewise possible to use other types of retaining means, for instance some type of clamps, securement by means of electric fields or the like.

Four pivotable units 103, 104, 105 and 106 are located in a rectangular pattern about said plunger device 101. The pivotable units are pivotable about the one of their edges that faces the plunger device and the units are positioned in such a manner that two opposite members, 103 and 104, when pivoting, move into engagement with those panels 2 of the box blank sheet retained by the plunger device that correspond to the side walls of the box. The other pivotable units 105 and 106, which likewise are disposed opposite one anotner, are arranged to pivot in a similar manner into engagement with the panels 3 of the box blank sheet corresponding to the end walls of the box.

Intermediate the plunger device 101 and the pivotable units 103, 104, 105 and 106 projecting elements preferably are provided, onto which the box blank sheet may be fitted by means of recesses 10 formed in said blank sheet and having a configuration corresponding to that of the projecting elements for the purpose of ensuring safe application in the correct manner of the blank sheet in the apparatus and preventing displacement thereof during the operation of the apparatus. In accordance with tne embodiment illustrated the projecting elements consist of raised edges 107.

In order to further retain the box blank sheet and also to ensure that the panels 2,3 of the box blank sheet corresponding to the end walls and the side walls, respectively, of the box will bulge slightly in preparatory to the erection, the pivotable units 103, 104, 105 and 106 are provided with locking means 110 and 111. The locking means ensure safe abutment of the box blank sheet against the pivotable units 103, 104, 105 and 106 during the erection of the box. In accordance with the embodiment shown, these locking means consist of clamping means 110 and 111 which are positioned on the pivotable units. The clamping means 110 and 111 are pivotally mounted on the pivotable units spaced from the axis of rotation of the corresponding unit, thus allowing the clamping means to be lowered to clampingly engage the box blank sheet. Because the clamping means are positioned comparatively centrally lengthwise on the pivotable units, said units will cause the blank sheet to bulge if the pivotable units are at the same time formed with cavities or at least with impressions in the areas where the clamping means exert their clamping action. The magnitude of the bulge will depend, however, on the one hand on the type of material of the box blank sheet and on the thickness thereof and on the other, on the difference in levels between the impression or cavity and the surrounding surfaces. The pivotable units could for instance be formed with two ribs, one on either side of the clamping means and directed away from the bottom panel of the box blank sheet. Obviously, other embodiment modifications are possible to produce the level differences in the pivotable units.

On the pivotable units 103 and 104 that engage the side walls of the box, flap folding means 115 are provided which in accordance with the embodiment illustrated project from the edge of the pivotable units that is spaced from the rotational axis of said units, and the projecting parts of said flap folding means are bent in such a manner that they extend above the pivotable units towards the box blank sheet. These flap folding means force the flaps 11 projecting from the side wall panels 2 of the box blank sheet to be folded upwards upon actuation of the clamping means 111, whereby said flaps will assume a position essentially at right angles to the plane of the box blank sheet. When the pivotable units 103 and 104 are set in motion the distance by which said flap folding means project past the plane of the pivotable units is reduced at the same time, said distance, when the pivotable units have reached their fully upwards pivoted position, becoming zero or negative. In other words, in this position the flap folding means do not project past the pivoting units. In this upwards-pivoted position the flaps 11, having already been folded outwards, thus may be inserted in the slits or slots 12 intended therefor without the flap folding means 115 exerting a pressing action on the corner panels 4. Obviously, other types of flap folding means are conceivable, such as pressure-exerting plunger means or pivotable plates.

To fold the corner panels 4 of the box blank sheets cam faces 120 are used in accordance with the present embodiment. These cam faces 120 force the corner panels 4 to be erected into a position essentially at right angles to the rest of the box blank sheet when the sheet is applied in position in the apparatus by means of the plunger device 101 and the suction cups 102. Other ways of effecting erection of the corner panels can also be used, such as by means of plunger devices that may be extended against the corner panels, upwards pivotable plates, or the like.

Folding downwards of the upper parts of the corner panels is effected in accordance with the shown embodiment with aid of two separate means. Initially, a first folding means 122 is activated. This means is displaced in a direction in parallel with fold line 22 intended for the side walls 2 of the box blank sheet into a position closely adjacent one of the erected corner panels and interiorly thereof, i.e. on the side facing away from the cam surface 120. Preferably, this folding means is formed with a comparatively even upper edge which following the displacement will be positioned at a level corresponding to the intended corner panel folding line 21. In accordance with this embodiment the folding means are fixed to the pivotable units 104 and 105 for erection of the end walls and consequently this folding means accompany said units as the latter are pivoted upwards. The folding means also comprise curved hook-like end portions which, upon retraction of the folding means, ensure that the flaps 11 formed on the side wall panels and inserted into the corner panel slots 12 take part in the movement. This causes the flaps to be folded upwards into a position in which they extend approximately in parallel with the plane of the parts of the corner panels 4b into which they are inserted. In order to fold the upper part 4a of the corner panel over the folding means 122 a fold-over means 123 is used which in accordance with the embodiment shown comprises a plunge extendible from a stationary cylinder. The fold-over means serves to ensure that the upper part 4a of the corner panel is folded so as to extend essentially at right angles to the lower part 4b of the corner panel. Obviously, the fold- over means 123 may be configured differently.

In order to retain the inwards folded upper parts 4a of the corner panels in position during the erection of the end walls 3 the apparatus is equipped with retaining means 125. In accordance with the shown embodiment these means are positioned in the areas of the pivotable members 104 and 105 designed to erect the end walls that are spaced from the respective pivot shaft of said units. Said means comprise at least one pivot shaft, allowing the means to be folded down across the panels 3 of the box blank sheet intended to form the box end walls and to exert a pressing action on the downwards folded parts 4a of the corner panels. In accordance with the embodiment shown these retaining means further comprise piston-and- cylinder units 126 forming those parts of the retaining means that are arranged to abut against the downwards folded upper parts 4a of the corner panels. The piston- and-cylinder units 126 are used for additional folding of the downwards-folded parts 4a of the corner panels after insertion of the side wall flaps 11 into the slots 12 of the corner panels and after folding upwards of said flaps into their position in which they are essentially parallel with the plane of the portions of the corner parts 4b into which they are inserted. This is effected by extending the pistons of the piston-and-cylinder units 126 outwards so as to press against said parts 4a. The result of this additional folding downwards is on the one hand that the upward-folded flaps 11 are immobilised in their upwards-folded retaining position and on the other, that the flaps 13 of the downwards-folded parts 4a of the corner panels are made to engage in slits 14 formed in the end walls 3 and thus to be fixed m this inwards- folded position.

Although from the above description of one embodiment of the apparatus the procedure of erecting a box and its inter-connection in the apparatus is essentially already known, such erection and inter¬ connection will nonetheless, for the sake of clarity, be described step by step and in chronological order.

Initially, the plunger device 101 is extended and by means of the suction cups 102 it will grip a box blank sheet carrying it along in its retracting movement, so as to position said sheet in the apparatus. When the box blank sheet is thus applied in the correct position, on the one hand the cam faces 120 will force the box corner panels upwards into a position in which they extend essentially at right angles to the rest of the box blank sheet, and on the other, the box blank sheet will be fitted into the apparatus in such a manner that the edges 107 raised above the apparatus will project through the recesses 10 formed in the sheet, thus counteracting any tendencies in the box blank sheet to assume an incorrect position prior to the erection or to become displaced during said process. Thereafter, the locking means 110 and 111 are activated, being pivoted downwards and thus clamping in position respectively the end and the side walls of the box blank sheet. As the side walls of the box blank sheet are clamped in position the upright flap folding means 115 will also cause the flaps 11 of box blank side walls to be folded upright into a position into which they are essentially perpendicular to the rest of the box blank sheet. Then, the folding means 122 are extended, presenting the edge about which the upper parts 4a of the corner panels may be folded. This folding operation is effected by fold-over means 123 exerting a pressing action against the upper parts 4a of the corner panels on the faces thereof that are turned away from the folding means 122. During this operation the upper panel parts will be folded downwards so as to be positioned in a plane which is essentially perpendicular to the rest of the corner panels and thus essentially in parallel with the bottom panel 1 and side and end walls 2,3 of the box blank sheet. In order to retain the downwards-folded panels in this position retaining means 125 are folded outwards, said means exerting a pressing action against the downwards-folded parts, where upon the fold-over means 123 are retracted. The end walls of the box are then erected with the aid of the pivotable units 105 and 106. Also the side walls of the box are then erected and the flaps 11 of the side walls are fitted into the slots 12 formed in the corner panels for that purpose. During the erection of the side walls the upright flap folding means are retracted whereby, when the pivotable units 103 and 104 have reached their fully upwards-folded position and the flaps have already been inserted into the slots intended therefor, they no longer project further towards the box than do the upwards pivotable units. The folding means 122 are then retracted, the curved end parts thereof hooking into and pulling along the inserted flaps 11 into a position wherein the latter are essentially parallel with to the planes of the parts 4b of the corner panels into which they are inserted. In this position, with the flaps 11 being folded upwards, the side walls will be secured to the corner panels and because these corner panels are fastened to the end walls of the box, all walls of the box thus will be fixed to one another. In order to fix the flaps in their upwards-folded positions the already downwards-folded upper parts 4a of the corner panels will be folded downwards further against the other parts 4b of the corner panels, by the extension of the pistons of the piston-and-cylinder units 126 of the retaining means 125, whereby the flaps 11 thus will be trapped between said two panel parts and thus be prevented from being dislodged from the upwards folded position. The upper parts 4a of the corner panels are forced sufficiently far inwards towards the other parts 4b of the corner panels that the flaps 13 positioned on the outer edges of the inwards-folded parts 4a are caused to engage in the slits 14 formed in the end walls for that purpose, thus causing the inwards-folded parts 4a to be secured in position and the box is ready. Finally, the plunger device 101 lifts the box which is still gripped by the suction cups 102, whereupon the box is transported aside. The plunger device 101 is then again extended to fetch a fresh box blank sheet and the erection cycle is closed.

All moveable parts of the apparatus preferably are driven by pneumatical or hydraulic means.

However, it should be mentioned, finally, that several modifications of the above embodiment are possible within the scope of the present invention as defined in the claims. Various part operational steps may be solved by means designed differently than shown and described herein. Without in any way being exhaustive, a number of such modifications of the various part means also have already been mentioned in the description of the configuration of the means in accordance with the present embodiment. Instead of employing several means, as specified with respect to the present embodiment, which simultaneously carry out the erection and assembly steps related to several parts of the box it is likewise possible to use less numerous units of identical means and then, by turning the box blank sheet, carry out identical operative steps in sequence on the various parts of the box blank sheet. It should also be noted that although the embodiment above has been described in connection with folding of a particular box the apparatus may be adapted, without having to be modified in any extensive way, to erect and assemble boxes of other types. For instance, boxes having folded corners that are not triangular are possible, in which case the piston of the piston-and-cylinder unit may also be prolonged. It is likewise possible to assemble boxes having pre-glued strips or the like instead of flaps and slits as described in the foregoing. In addition, the box parts may be connected to one another by means of stapling, in which case the apparatus in accordance with the present invention may be supplemented with separate stapling means. Appararuses for assembly and erection of such boxes should be considered to be within the scope of the present invention, since only very small modifications, if any at all, with respect to the apparatus described in the embodiment above are required for this purpose.

Claims

1. A box erection apparatus for erecting boxes having folded corners and being made from a one-piece box blank sheet, in which apparatus the sheet is applied so as to be held securely therein, and which apparatus is provided with pivotable units (103, 104, 105 and 106) which, when pivoting, raise the end walls and the side walls (2, 3) of the box into an upright erected position, c h a r a c t e r i z e d in that the apparatus comprises at least one corner folding device comprising an erecting means (120) folding a corner panel (4) into an upright position where in said panel extends essentially perpendicularly to the plane of a box blank sheet, a folding means (122) which is caused to abut against the corner panel face that is turned away from the erecting means, and a fold-over means (123) folding an upper part of the corner panel (4a) downwards into a position on top of the first folding means (122), and that the pivotable units (105, 106) for erection of the end walls are formed with retaining means (125) that are spaced a distance away from their respective pivot axis, which retaining means are folded down against the end walls panels while exerting pressure on the folded upper parts (4a) of the corner panels (4), whereby the latter will be retained in position during the erection of the end walls (3) of the box.

2. A box erection apparatus as claimed in claim 1, c h a r a c t e r i z e d in that the erecting means

(120) of the corner folding device comprises cam faces forcing the corner panels (4) to be folded inwards when the box blank sheet is placed in the apparatus.

3. A box erection apparatus as claimed in claim 1, c h a r a c t e r i z e d in that the box blank sheet is placed in position in the apparatus by means of an extendable plunger device (101) provided with at least one suction cup (102) .

4. A box erection apparatus as claimed in claim 3, c h a r a c t e r i z e d in that the extendable plunger device (101) is provided with four rectangularly disposed suction cups (102) .

5. A box erection apparatus as claimed in claim 1, c h a r a c t e r i z e d in that the pivotable units (103, 104) for erection of the side walls (2) of the box are provided with locking means (111) holding the sheet in position while at the same time imparting to said side wall a slightly bulging surface configuration.

6. A box erection apparatus as claimed in claim 1, c h a r a c t e r i z e d in that the pivotable units (104, 105) for erection of the end walls (3) of the box are provided with locking means (110) holding the sheet in position while at the same time imparting to said end walls a slightly bulging surface configuration.

7. A box erection apparatus as claimed in claim 5, c h a r a c t e r i z e d in that the pivotable units

(103, 104) for erecting the side walls (2) of the box are provided in the areas thereof corresponding to the upper edge of the side wall of the box with essentially perpendicularly upright flap folding means (115) which, upon securement of the side walls in the apparatus, force the flaps (11) formed on the side walls of the box blank sheet to be folded inwards relatively to the box blank sheet, and in that said flap folding means (115) , upon raising of the pivotable units (103, 104), are retracted in such a manner that when in their fully upright position they do not extend past the pivotable units (103, 104) towards the box.

8. A box erection apparatus as claimed in claim 7, c h a r a c t e r i z e d in that the folding means (122) has a bent end which, upon retraction of the folding means (122) engages the flap (11) inserted into a slot (12) formed in the corner panel (4), hereby said flap (11) is folded into an upright position to fasten the side wall (2) against the corner panel (4) .

9. A box erection apparatus as claimed in claim 1, c h a r a c t e r i z e d in that the retaining member (125) is provided with at least one piston-and-cylinder unit (126) which, upon actuation of the piston, exerts pressure on the inwards-folded part (4a) of the corner panel, causing the flaps (13) provided on the corner panel to engage the end wall of the box.