Patent IT-1236202-B (IT)
Title: Manufacturing system for paper and cardboard both for a single layer as well as for multiple layers in the same formation-box
IPC: D21F/
Filed: 1989-11-02
Granted: 1993-01-19
Abstract: This industrial invention deals with a system with which one can produce paper or cardboard in one or more layers, and in one or more colours, with layers of different weight and quality, in a single formation-box, with an original procedural plan which is conceptually very different from the present day methods used in paper making both in rolls, as well as flat, or vertically.The said system also permits all the paper production possibilities for one or more layers, in one or more superimposed colours, and in one or more weights or qualities, with a final superior quality result, so as render the system universal, with considerable system savings and extreme ease and adjustment of use.The system dealt with in this industrial invention is essentially made up of two superimposed boxes, between which a cloth runs, which is intended to collect one or more layers of fibre that will form the paper at the end of the process.In the upper box one or more mixture distribution groups are inserted, which in the case where they are more than one, creates the creation section, where each one of them creates a layer of the final paper, with the said and desired characteristics.This fact thus guarantees creation on the part of the system, of a multi-layer paper, or cardboard, with specific layer characteristics, as requested by producers, who can here also create layers of very different quality.In the lower box with respect to the cloth, an opportunity for aspiration is created, which determines the deposition of the fibres on the cloth. This box can also be subdivided into several sections, as many as there are groups in the upper box, that is to say as many as there are layers to be created.Once the layers are created, the cloth is coupled to a felt, which runs parallel to, and is coupled to the cloth itself, with overlaying of the one or more paper layers formed in the boxes.Successively the cloth is separated from the felt, and from the paper, to re-start the creation cycle, while the felt itself with the paper laid upon it, continues its course up to the presses, where the water content is reduced, and where it is finally separated from the paper, which will be subjected to all the final operations of a normal working cycle for the paper itself.The fact that the paper is laid upon the felt, also constitutes an important innovation, in as much as present day machines in the creation phase have the paper layers hung under the felt itself, with the possibility for continuous separation.The present technique calls for a system of creation constituted in general, from a long felt, indicated as the "laying-upon-felt", which receives the mixture from one or more creator drums, which the drum(s) have withdrawn from the creation box.Said mixture, in practice goes to form a layer of very wet paper, which is deposited on the lower part of the felt, with the help of a suitable cylinder called "laying-cylinder" in current parlance.The presence of one or more creator cylinders, with the relative "laying-cylinder" is used exclusively on the final paper layer(s).As the quality of the mixture can vary, so too can the colour and quantity of these creation groups also vary.As has already been said, the subject of the present industrial invention is a system, which substitutes, in an integral way, and with great production simplicity, the present day sectors for paper formation, so as to create the formation of various component layers of a final paper (of one or more layers) on the "withdrawing felt", and in particular on its upwardly turned surface, so as to be able to form different weight, different coloured and different quality-mix layers. All of this is achieved with great system economy and ease of management.