A method and apparatus for stacking interleaved paper towels or tissues
The present invention relates to a method and apparatus for stacking interleaved paper towels or tissues which minimises paper waste and provides continuity of supply in conventional containers without the need for a user to intervene and manually extract a towel which has jammed because of a lack of continuity in the interleaving.
The problem which underlies the present invention is that, owing to the standard dimensions of the rolls of paper used to make the towels or tissues, and to the standard dimensions of these, the last tissue or towel cut from one roll may be shorter than normal, which will lead either to its being discarded or to one shorter towel being included in each stack.
Discarding these items of course increases costs, while including a shorter towel every x towels of normal length can inconvenience the user.
A further disadvantage is that the user may be obliged to introduce his fingers into the paper towel distributor in order to locate a shorter towel which has not been correctly interleaved.
The object of the present invention is to ensure physical continuity between two shorter tissues or towels, in order to eliminate the aforesaid problems simply and at low cost.
This object is achieved according to the present invention by providing a method and apparatus for carrying it out having the characteristics specifically claimed in the Claims which follow.
Additional characteristics and advantages of the present invention will become clear from the detailed description which follows, provided purely by way of non-limitative example, with reference to Figures 1 and 2, which illustrate an installation according to the invention.
With reference to the drawings, a plurality of rolls of paper is indicated 2. Each roll 2 is cut into strips 4 of the required width, by methods known in the art and not shown for the sake of simplicity.
Each strip 4 arrives at a respective folding assembly 6, with a continuous band 8 being created thereby which includes a predetermined number of sheets which are interleaved by methods known in the art and not shown for the sake of simplicity. The sheets may be interleaved as a V, a Z, a W configuration or to other folding methods .
The continuous band 8 arrives at a cutting station 10 where it is cut into portions of the required length by means of a cutting device T which is per se known. This creates packs P of interleaved sheets of a predetermined width.
As explained above, should the last towel or tissue of a pack P be shorter than the required length, the pack P is forwarded to
a gluing station 20 where a nozzle U spreads a thin layer of adhesive on the edge of the shorter towel and the pack P is deposited in a stacking container 30.
The same operation is repeated for the subsequent pack P, which is deposited in the stacking container 30 on top of the preceding pack P. The two shorter sheets are thus stuck together.
The operation continues until the container 30, the dimensions of which are chosen so as to hold a particular number of packs P, corresponding to the number of towels which are contained for use in a particular type of container, has been filled.
The advantages of the invention are clear from the aforesaid description: it prevents paper from being wasted and it provides physical continuity between the towels or tissues of different packs, thereby preventing interruptions in the interleaving which could cause problems for the user.
Naturally, the principle of the invention remaining unchanged, manufacturing details and embodiments may vary widely from those described and illustrated, without departing thereby from the scope of the invention.
In particular, for example, a pack counter could be provided in order to prevent adhesive from being deposited on the final pack to be stacked in a container, thereby saving on adhesive.
A presser device could also be provided to facilitate adherence between sheets of different packs stacked in the container.
The use of more than one roll of paper, each associated with a particular number of folders, would provide a continuous interleaved band containing a greater number of sheets . In this way, the number of packs to be stacked could be reduced, while at the same time reducing the speed of operations and thus damage to the paper or, alternatively, the productivity of the plant could be increased, without increasing the risk of damaging the paper compared to that when using a single roll of paper .
It is also clear that the gluing operation described above could also usefully be used in the event of the final tissue or towel not being of a different length to the preceding ones, in order to provide physical continuity between the various interleaved packs .