The present invention refers to a device for introducing a winding core into a re-reeling machine.
As is known, in the paper industry the production process envisages a stage in which the paper, at the end of the production process and prior to the stage of packaging in a commercial format, is wound in rolls of large dimensions. From these rolls the paper is unwound and treated to be converted into a format suitable for marketing.
In what follows, reference will be made to paper products prepared for sending to the market in the form of rolls, such as toilet paper, paper towels, and the like.
In these cases, the paper must be unwound from the original roll and, after undergoing the treatments required, must be re-wound on a secondary roll. Finally, the secondary roll is cut according to planes orthogonal to its own axis into rolls of smaller size.
Usually these treatments involve making lines of preferential tearing that are transverse to the ribbon of paper. The tearing lines are made using machines, which are in themselves known, provided with rotary blades over which passes the ribbon of paper being processed.
The machines that perform this operation on the one side support the primary roll, from which the ribbon of paper is unwound in continuous manner, and on the other have a winding assembly for winding the ribbon of paper, on which the preferential tearing lines are made, into secondary rolls.
Since from a primary roll a number of secondary rolls of pre-determined dimensions are usually obtained, the assembly for winding into rolls is integrated with a device for introduction of the winding cores, on which the ribbon of paper that is to form the secondary rolls is wound.
The said introduction device introduces a tubular cardboard core only after a given amount of ribbon of paper has been wound on a previous core and at the same time causes tearing of the ribbon in such a way that from the re-reeling machine it is possible to take out a roll that is already of commercial thickness. This roll may subsequently be packaged and marketed.
The stage of introduction of the cardboard cores into the winding assembly must be performed with extreme precision. Consequently, an important technical problem is obtaining an optimal precision in the introduction of the cores into the winding assembly, with a level of performance superior to what has been achievable up to now.
A purpose of the present invention is therefore to solve the above technical problem by providing a device for introducing a winding core into a re-reeling machine that may enable introduction of the cores into the winding assemblies in a very precise way so as to guarantee the production of high-quality articles.
Another purpose of the present invention it to provide a device that will enable production of rolls with a very precise number of sheets or lengths of paper.
A further purpose of the invention is to provide a device that is substantially inexpensive and at the same time extremely versatile.
Up to the present day, in fact, the devices used have been of the mechanical cam type or linkage type. In these devices, movement of the winding core depends on the profile of the cam or the geometry of the linkage, whereas in the device according to the present invention the movement of the winding core may be varied electronically.
Not the least important purpose of the invention is to provide a device for introducing a winding core into a re-reeling machine that is basically simple, safe and reliable.
These and other purposes according to the present invention are achieved by providing a device for introducing a winding core into a re-reeling machine, as specified in the Claims.
Further characteristics of the present invention are moreover defined in the subsequent claims.
Advantageously, the device according to the invention enables the formation of rolls of paper with a very regular start of winding.