A method of sealing and retaining boxes stacked upon each other in a predetermined position

Abstract

 Method of handling parallelepipedic objects such as boxes and the like.
To avoid sliding of the boxes (1) relatively to each other when stacked, the boxes are provided with a tape (14) made of a plastic foil with a friction increasing surface.

Description

[0001] This invention relates to a method at the storage, transport and other handling of parallelepipedic objects, particularly boxes, cartons and the like. The invention more definitely relates to a handling method, at which objects are stacked, for example, in the form of load units or on pallets, and at storage.

[0002] It is a problem well-known that objects, particularly boxes of corrugated board or cartons with smooth surfaces when being stacked have a tendency of sliding relatively to each other. As a result thereof, the stack gets disarranged and, in the worst case, collapses.

[0003] In view of the high requirements of today on rational handling of goods, which when being in the form of boxes substantially are handled as pallet loads by means of trucks, such instable stacks constitute a serious problem, because re-stacking can take place only by tedious manual work.

[0004] As regards boxes of corrugated board, several proposals have been made in recent years for solving the problem.

[0005] According to one proposal, the corrugated board is treated in the corrugated board machine by coating with a colloidal solution of silicon or aluminium oxide, which increases the stiffness of the fibres in the surface of the paper sheet and thereby produces an irregular fibre networli, which provides a certain friction effect.

[0006] The method, however, gives rise to difficult problems and breakdowns in corrugated board mills, particularly as a result of the silicon dioxide, because the material solidifies and builds up incrustrations in the application equipment. It was found, moreover, that the material has a corroding effect on the remaining machine equipment. Modified silicon oxides, it is true, which facilitate cleaning have been tested, but the high costs of such modifications so far have limited their use. As regards the aluminium oxide, it gives rise to troublesome dusting problems.

[0007] According to another proposal, the corrugated board is coated with organic solvents increasing the friction. Hereby, however, the printability of the corrugated board is deteriorated substantially, and it becomes for most of the materials smeary and troublesome to handle.

[0008] It also had been suggested to bring about ruggedness of the corrugated board surface by mechanical treatment. The ruggedness is obtained by puncturing the outer liner layer prior to its application, whereby on the resulting corrugated board sheet projections are formed. Such projections, however, are effective only upon contact with a rough or uneven surface. At greater loads, for example at the stacking of heavy boxes, the projections are depressed, and the friction effect does not come off.

[0009] Another method of preventing stacked boxes from sliding relatively to each other is to treat the top of boxes after their completed packaging with a non-drying adhesive agent. When sufficient amounts of the agent are applied, certainly the boxes are retained very effectively against each other, but quite naturally both the application of the agent and the handling of the bpxes after the breaking of the stack involve considerable inconveniencies.

[0010] Finally, a method can be mentioned at which stacked boxes are retained to each other by applying adhesive spots in the form of so-called hot-melt. This method has the disadvantage that it is very difficult later on to separate the boxes from each other without destroying them.

[0011] At present, boxes most often are transported on pallets. In such cases the problem is solved by fixing the load by means of a shrinking or stretching film. This, certainly, holds the load together in an effective manner, but is very expensive and does not solve the problem when the plastic film is broken, for example at the handling of the pallet-loads and their storage with the receiver.

[0012] According to the present invention the problem is solved thereby, that the surfaces of the objects to be handled and be brought into contact with other objects in a stack or with a support are provided with a strip of a tape made of a plastic foil with rough surface.

[0013] When the objects are cartons, boxes or the like with sealable cover, for example so-called slot boxes, the sealing can be effected by means of the friction increasing tape.

[0014] It is per se previously known to make plastic foils with rough surfaces, so-called non-skid plastic foils, which have been used for wrapping wood packages carried by sea. The foil is manufactured by co-extruding two plastic films, to one of which an expanding agent is added which forms cells in the film. The foil is subjected to stretching, whereby the cells break and on the final film an irregular pattern with retiform elevations is formed, rendering the foil as rugged a; desired.

[0015] The invention is described in greater detail in the following by way of an embodiment and with reference to the accompanying drawing.

[0016] The drawing shows in a schematic manner the closing of a slot-box 1 along a plurality of stations 2,3,4,5, at which the cover tips 6,7, 8,9 in turn are folded inward so that at the last station 5 the closed box is obtained. The box is moved from here to a station 10 for sealing the cover, which is carried out by means of a fr:ction tape 11 according to the invention. The tape is taken from a supply reel 12 and passed over suitable means for sealing the cover tips 7 and 9. The sealing finally is ensured by applying with rollers 13 or other suitable means pressure to the applied tape strip 14. If desired, also the lower side of the box can be provided with a tape stip from a reel 15.

[0017] The invention is not restricted to the embodiment shown, but can be varied within the scope of the invention idea.

Claims

1. A method of retaining objects stacked upon each other in a predetermined position relative to each other during the storage, transport or other handling of the objects, mainly in order to prevent the objects from sliding relatively to each other or to a support,
characterized in that the objects are provided with a tape made of a plastic foil with a friction increasing surface.

2. A method according to claim 1,
characterized in that the foil is provided with rough retiform elevations.

3. A method according to claim 1,
characterized in
that the objects are cartons, boxes or the like with sealable cover, for example so-called slot-boxes, and that the sealing is carried out with the friction increasing tape.

Drawing