Patent ID: 6922980

Claim:
An apparatus for making a tubular length of stretch film, the apparatus being applicable to machines or lines for making packages containing groups of products wrapped with stretch film, and comprising: a feed table, extending in a defined direction, on which the groups of products presenting a front face are formed; a station for making the packages, located on the feed table and being equipped with means for unwinding the stretch film and forming the length of the film around package preforming means, located on the feed table and being mobile between several working positions in order to stretch the length of film for obtaining a cross section of the length of film larger than the front face of the group of products, thus enabling the group of products to be fed into the station and, after the package has been formed, to be fed out onto the feed table again; wherein the means for unwinding and forming the film length comprise: a roll of stretch film located near the means for preforming the package; means for cutting a length of the film unwound from the roll and located upstream of the preforming means; a telescopic unit comprising: an actuating arm pivoted at its lower end to a fixed supporting structure for swinging about a vertical axis coinciding with a line passing through the center of the preforming means; a rod slidably housed inside the arm and equipped at its upper free end with a gripper that holds a leading end of the film; the rod being mobile between several working positions from a withdrawn position in which the rod is inside the actuating arm, keeping the gripper outside it, and an advanced position in which the rod forms an extension of the arm; synchronized drive means being provided to act on the arm and on the rod for pulling the film being held by the gripper along a ring shaped path around the preforming means; the means for unwinding and forming the film length further comprising a unit, located close to the preforming means, for stably joining leading ends of the film together to form the length of film into a tubular shape around the preforming means.