Machine for the production of tubes by winding strips of weblike material

#This application is the U.S. national phase of PCT application PCT/IT2006/000857 filed on Dec. 19, 2006, with a claim to the priority of Italian application FI2005A000258 filed on Dec. 23, 2005.

#The present invention relates to a core-winder, i.e. a machine for the production of tubes by winding one or more strips of weblike material, e.g. set on top of one another and partially staggered in a helically shaped arrangement, or in a longitudinal arrangement.

#Machines of this type are commonly used for the production of tubes of cardboard or other sheet material on which to wind weblike material, such as paper, tissue paper, plastic film, aluminium sheets or the like. These tubes are usually circular in cross-section. Tubes thus produced can also have different shapes and cross sections, such as circular, square, rectangular, or other. Such tubes can be used not only as winding cores for the formation of rolls or logs of weblike material, but can also be designed for various different applications, as containers for foodstuff products, for soap powders, or for other applications. In sequel the present description reference will be made to the formation of circular tubes used as winding cores for weblike materials; however, the scope of protection of the present invention is not limited to this application, but it is understood as extending to all the sectors that regard formation of tubes from one or more wound strips of weblike material.

#The invention will be understood more clearly from the description and the attached drawings, which show a practical non-limiting embodiment of the invention. More in particular, in the drawings:

#FIG. 1 is a side view of a core-winder on which the invention can be implemented;

#FIG. 2 shows a longitudinal cross section in a plane containing the axis of the spindle, in a position corresponding to the area of cutting of the tube; and

#FIG. 1 shows as a whole a possible embodiment of a core-winder, to which the present invention is applied. It should, on the other hand, be appreciated that the invention can be applied also to machines of different structure, provided that they are equipped with a winding spindle for the formation of the tubes, which can be fixed or else rotary (advantageously supported idle) about its own axis, and that they call for a device for cutting, into lengths or tubular portions of given length, the tube that is formed continuously around the spindle.

#In brief, and limitedly to what concerns the present description, the machine of FIG. 1, designated as a whole by 1, comprises a load-bearing structure 3, by which a spindle 4 is supported in cantilever fashion, a first end of which is constrained to the load-bearing structure 3 via a sleeve 8. The opposite end of the spindle 4 terminates in the proximity of the area in which the tube is cut. A conveyor or equivalent means (not shown) then moves away the individual tubular products obtained by cutting a tube T, formed continuously as described herein around the spindle 4.

#To form the tube T, one or more strips made of cardboard or other continuous weblike material are fed to the core-winder 1. In the example shown, two strips designated by S1 and S2 are used. These are fed and wound helically around the spindle 4 with the aid of a feeding and winding device 5 comprising, in the example illustrated, a continuous belt 7, which has two branches 7A and 7B, entrained by two pulleys 9 and 17, the respective axes of rotation of which are designated by 9A and 17A. The branch 7A forms a helical turn around the spindle 4 and around the strips of weblike material S1 and S2 in the course of winding. Designated by 19 is the motor that carries the drive pulley 17, which causes movement of the belt 7, in rotation.