GB2177340A

GB2177340A - Cutting in a packaging operation

Info

Publication number: GB2177340A
Application number: GB08614391A
Authority: GB
Inventors: Armin Hofmann
Original assignee: Sapal SA
Current assignee: Sapal SA
Priority date: 1985-06-20
Filing date: 1986-06-13
Publication date: 1987-01-21
Also published as: IT8620192A1; DE3614917A1; IT8620192A0; JPS624013A; CH664742A5; IT1191737B; GB8614391D0

Abstract

The apparatus comprises a table (10) for transporting a strip (11) of packaging material, means (12, 13) for continuously driving this strip and a cutting member (15) for cutting sheets of given length from this strip. The cutting member (15) is designed so that by the act of cutting, the rear end of a cut off sheet is deflected downwards to clear a free space sufficient to allow the new leading end of the strip to continue to advance while the cut off sheet is halted by stops 26 and while the leading end is partly superposed on the latter. While the sheet is halted glue nozzles 25 act on it against anvil 27. <IMAGE>

Description

SPECIFICATION Process for packaging products and apparatus for carrying out the process BACKGROUND OF THE INVENTION The present invention relates to a process for packaging products and more particularly food products such as chocolate bars for example, wherein a band of packaging material is continuously unreeled and this band is cut to form sheets of said material which are each then glued and folded around the product.

It also relates to an apparatus for carrying out this process, comprising a mechanism for continuously feeding a band of packaging material, a cutting member for successively cutting off sheets of this material, halting stops for halting each sheet during a glueing phase and means for taking up said previously glued sheet and bringing it forward over a folding box.

One of the problems encountered in packaging machines is that of feeding a packaging material in the form of a continuous band taken off a roll. On the machines provided for box-folding, feeding of the packaging material comprising at least one sheet of packaging material coming from the roll and possibly a precut label, is usually effected discontinuously. The packaging material coming from a large roll is variably unreeled, while this involves very abrupt acceleration and braking due to the high operating rates of these machines. The rolls of packaging material are of great weight, especially when they start being used, and they thereby present a non-negligible inertia. The traction exerted on the packaging material, whoch is selected to be relatively thin for evident reasons of economy of material, may cause rupture of the band, especially during acceleration.

The difficulty in this problem is substantially due to the packaging operation comprising working phases which are effected discontinuously, whereas it would be advantageous for the above-mentioned reasons to unreel the paper continuously.

SUMMARY OF THE INVENTION An object of the present invention is to meet the problems of known machines by eliminating variable unreeling and the drawbacks associated therewith.

To this end, the packaging process accord- ing to the invention is characterized in that at the moment when the band is cut and the cut off sheet is halted for glueing, the rear end tab of this sheet is simultaneously folded down to clear a sufficient space to allow the front end of the band of packaging material to continue advancing while the cut off sheet is halted, while it is partly superposed on the latter.

Likewise to this end, the apparatus according to the invention is characterized in that it has a cutting member arranged so as to downwardly repel the rear end tab of a sheet cut off the band, in such a manner as to clear a sufficient space to allow the front end of the band to continue advancing while the cut off sheet is halted, while it is partly superposed on the latter.

DESCRIPTION OF BEST MODE The present invention may be better understood with reference to a preferred embodiment given by way of example and to the accompanying drawings wherein: Figure 1 shows a sectional elevation of the apparatus according to the invention, Figure 2 shows a top view of this apparatus and Figure 3 shows an enlarged schematic view illustrating the trajectory of the cutting member and the movement of the rear end tab of the cut off sheet.

With reference to the figures, the apparatus comprises a table 10 for transporting a band 11 of packaging material taken from a roll (not shown) and pulled in the direction of the arrow A by two rolls 12 and 13 bearing against each other and rotating in opposite directions indicated by the arrows B and C. One of these rolls is a driving roll and the other is a pressing roll which cooperates with the driving roll to grip the band 11 of packaging material.

A drum 14, rotatingly driven continuously in the direction of arrow D, carries a cutting member having a cutting edge 16 which is laterally offset with respect to the opposite edge 1 7 that is disposed on a diameter of the drum 14. The cutting edge 16 cooperates with a counter-cutting edge 18 of a part 19 of hard metal fixed by screws 20 on a block 21, disposed under the transporting table 10.

The part 19 of tempered metal may be adjusted in height by a screw 22.

The working table 10 is extended by a plate 23 generally called a joining table when the package is composed of several papers to be joined on this table which presents at its upper surface and along its leading edge disposed in the vicinity of the rear end of the transporting table 10 a clearance 24 whose role will be further described below. A mobile support which is displaceable in the direction of the double arrow E, carries both glueing nozzles 25 and mobile stops 25 capable of traversing openings 26' of appropriate form and dimensions provided in the joining table 23. An anvil 27 is disposed above the glueing nozzles to permit holding the packaging material when the nozzles 25 are brought into a high position for depositing glue spots on the bottom surface of this material.The halting stops 26 ensure momentary halting and centering of the sheets of packaging material in the glueing phase. A clamp 28 is designed to grasp the extremity of a sheet of packaging material and to bring it forward to its operative position more particularly under the folding boxes. A recess 29 is provided at the extremity of the plate 23 to allow access of the clamp to the sheet of packaging material.

The band of packaging material is continuously unreeled and its extremity is displaced along the table 10 and the plate 23 until it touches the stops 26 which are at this instant in the raised position. The speed of rotation of the drum 14 is adjusted in such a manner that the cutting member 15 at the same instant cuts the band to realize a sheet of packaging material whose length corresponds to the distance between the stops and the counter-cutting edge 18 of the hard metal part 19.

The drum 14 continues to turn and the cutting member 15, due to its form and its position on its trajectory immediately after cutting, folds down the end tab of the sheet which has just been cut off. This folding down is made possible by the existence of the clearance 24 of the plate 23. Thanks to this folding down, the extremity of the band can advance while the cut off sheet is halted. This allows the glueing nozzles to be brought to their high position (shown in the drawing) and glue spots to be thereby deposited at the desired points on the bottom surface of the cut off sheet of packing material. When this operation has been effected, the stops 26 and the glueing nozzles 25 are returned to their low position, which thereby allows free passage of the extremity of the band on the plate 23.

When this extremity arrives in the vicinity of the halting position defined by the stops 26, the latter are returned upwards and a new sheet is cut off by the cutting member 15.

Fig. 3 illustrates more explicitly the movement of the sheet of packaging material cut off the band 11. As previously mentioned, the trajectory followed by the cutting member 15 is such that the rear end 31 of the sheet 30 is folded down, as is shown in the figure, while this allows the front end 32 of the band 11 to be superposed on the end section 31.

In this way unreeling the roll and advancing the band 11 may be effected continuously, in spite of momentary halting of the cut off sheet 30.

As previously mentioned, this procedure allows continuous unreeling of the band of packaging material to be made compatible with the utilization of the sheets cut off this band in accordance with alternative operating modes.

Claims

1. Process for packaging products and more particularly food products such as chocolate bars and the like, wherein a band (11) of packaging material is continuously unreeled, this band is cut to form sheets of said material, each of said sheets is then glued and folded around a product, and wherein at the instant when the band is cut and the cut off sheet is halted for glueing, the rear end tab of this sheet is simultaneously folded down to clear a space which is sufficient to allow the front end of said band to continue to advance while the cut off sheet is halted and while it is partly superposed on the latter.

2. Process according to claim 1, wherein the rear tab of a cut off sheet is folded down by means of a cutting member (15).

3. Apparatus for carrying out the process of claim 1, comprising a mechanism (12, 13) for continuously feeding a band (11) of pack aging material, cutting member (15) for suc- cessively cutting off sheets of this material, halting stops (26) for halting and centering each sheet during its glueing phase, and a clamp (28) for taking up this previously glued sheet before bringing it under a folding box, wherein said cutting member (15) is arranged to fold down the rear end tab of a sheet cut from this band, so as to clear a space which is sufficient to allow the front end of the band to continue to advance while the cut off sheet is halted and while it is partly superposed on the latter.

4. Apparatus according to claim 3, wherein said cutting member (15) is mounted off-center on a rotating drum (14), and wherein a plate (23) serving as a support for the previously cut sheets comprises at its upper surface and at its leading end a clearance (24) aliowing passage of the cutting member at each revolution of the rotating drum and folding down the rear end tab of the cut off sheet.

5. Apparatus according to claim 4, wherein said cutting member has a cutting edge (16) which is laterally offset with respect to an opposite edge (17) of said cutting member (15), said opposite edge (17) being disposed on a diameter of said drum (14).

6. Process and/or apparatus for packaging products substantially as hereinbefore described with reference to the accompanying drawings.