Apparatus for wrapping products with film

Abstract

A wrapping apparatus for wrapping groups of products with a film includes conveyor elements for supporting and moving groups of products, a feeding unit for dispensing film portions of defined length through a transverse opening of the conveyor elements, a wrapping unit including a plurality of crossbars supported by respective rods and arranged for picking the film portions and wrapping the film portions around the groups of products and a hub arrangement, rotatable about a rotation axis and slidably supporting the rods to be mobile linearly and transversely to the rotation axis and rotatably about the rotation axis, the crossbars being moved along a wrapping trajectory, and a guiding assembly engaged by the rods and/or the crossbars for guiding the crossbars along the wrapping trajectory changing a distance of the crossbars from the rotation axis during a rotation of the respective rods.

1 - 14 . (canceled) 
     
     
         15 . A wrapping apparatus associable with a packaging machine for wrapping with a film made of plastic material groups of products, including:
 conveyor elements for supporting and moving said groups of products along a longitudinal advancing direction and forming a supporting plane of said products;   a film feeding unit positioned under said supporting plane for dispensing film portions of defined length through a transverse opening of said conveyor elements so as to engage said groups of products;   a wrapping unit that includes a plurality of crossbars, each of which supported by at least a respective rod, wherein said crossbars are arranged for picking said film portions that come out from said transverse opening and wrapping said film portions around said groups of products, an hub arrangement that is rotatable about a rotation axis and slidably supports said rods of said crossbars so that said rods are mobile linearly and transversally to said rotation axis and rotatably about said rotation axis and said crossbars are consequently moved along a defined closed loop wrapping trajectory; and   a guiding assembly engaged by said rods and/or by said crossbars for guiding the latter ones along said wrapping trajectory changing a distance of said crossbars from said rotation axis during a rotation of said respective rods;   wherein said apparatus can be coupled in a removable manner to said hub arrangement so as to change a number of said rods and of said respective crossbars and an angular distance between said rods around said rotation axis according to dimensions of products and/or a pitch between successive groups of products on said supporting plane.   
     
     
         16 . The wrapping apparatus according to  claim 15 , wherein said crossbars are transverse to said advancing direction and parallel to said supporting plane. 
     
     
         17 . The wrapping apparatus according to  claim 15 , wherein each crossbar is fixed to an end portion of a respective rod that is removably connected to said hub arrangement by means of a respective supporting arm that is suitable to slidably support said rod transversely to said rotation axis. 
     
     
         18 . The wrapping apparatus according to  claim 17 , wherein the hub arrangement includes a central body that is rotatably connected to a frame of said wrapping unit about said rotation axis and includes a fastening assembly for removably fastening a desired number of supporting arms for respective rods. 
     
     
         19 . The wrapping apparatus according to  claim 17 , wherein said hub arrangement includes at least a central body that is rotatably connected to a frame of said wrapping unit about said rotation axis and is provided with a definite number of supporting arms for respective rods, and said central body is removably fixed to said frame and interchangeable with one of a plurality of central bodies which have a different number of supporting arms. 
     
     
         20 . The wrapping apparatus according to  claim 15 , wherein each crossbar is fixed to end portions of a respective couple of rods that are removably connected to said hub arrangement through respective supporting arms at opposite sides of said conveyor elements. 
     
     
         21 . The wrapping apparatus according to  claim 20 , wherein said hub arrangement includes two central bodies rotatably connected to a frame about said rotation axis at opposite sides of said conveyor elements, wherein each central body includes a fastening assembly for reversibly fastening a desired number of supporting arms and rods or wherein each central body is removably fastened to said frame and is interchangeable with one of a plurality of central bodies which have a different number of supporting arms. 
     
     
         22 . The wrapping apparatus according to  claim 18 , wherein said fastening assembly includes a plurality of fastening elements, which are mutually angularly spaced around said rotation axis, and a supporting arm is reversibly fixed to the respective fastening element. 
     
     
         23 . The wrapping apparatus according to  claim 21 , wherein said fastening assembly includes a plurality of fastening elements, which are mutually angularly spaced around said rotation axis, and a supporting arm is reversibly fixed to the respective fastening element. 
     
     
         24 . The wrapping apparatus according to  claim 15 , wherein said guiding assembly includes a guiding element that is arranged on a side of said conveyor elements and provided with a seat that extends along said wrapping trajectory and is arranged to slidably receive a coupling element of said rod and/or of said crossbar. 
     
     
         25 . The wrapping apparatus according to  claim 15 , wherein said guiding assembly includes a couple of guiding elements arranged on opposite sides of said conveyor elements and provided with respective seats that extends along said wrapping trajectory and is arranged for slidably receiving a coupling elements of said rod and/or of said crossbar. 
     
     
         26 . The wrapping apparatus according to  claim 24 , wherein said guiding element includes a first upper portion suitable for supporting and guiding said crossbar along a first operating stretch of said wrapping trajectory that extends above said supporting plane, and a second lower portion for supporting and guiding said crossbar along a second return stretch of said wrapping trajectory that extends under said supporting plane. 
     
     
         27 . The wrapping apparatus according to  claim 24 , wherein said guiding element is removably fixed to a frame of said wrapping unit and is interchangeable with one of a plurality of guiding elements provided with respective seats in order to modify said wrapping trajectory. 
     
     
         28 . The wrapping apparatus according to  claim 27 , wherein said first upper portion of said guiding element is removably connected to said second lower portion and interchangeable with one of a plurality of first upper portions in order to modify said first stretch of said wrapping trajectory. 
     
     
         29 . Bundling packaging machine for wrapping a plurality of products with a film made of plastic material, that includes a wrapping apparatus according to  claim 15 .