Apparatus and method for manufacturing a wrapped endless rod of substantially flat continuous material

Abstract

The method for manufacturing a wrapped endless rod of substantially flat continuous material comprises the steps of providing a substantially flat continuous material, treating the substantially flat continuous material with corona discharge and forming the corona treated substantially flat continuous material into an endless rod. Further steps comprise providing a wrapper, applying adhesive to the wrapper and wrapping the endless rod with the wrapper. Therein the step of applying adhesive to the wrapper comprises applying adhesive over a width of the wrapper and in a central portion of the wrapper.

1 . Method for manufacturing a wrapped endless rod of substantially flat continuous material, the method comprising the steps of:
 providing a substantially flat continuous material;   treating the substantially flat continuous material with corona discharge;   forming the corona treated substantially flat continuous material into an endless rod;   providing a wrapper;   applying adhesive to the wrapper, and   wrapping the endless rod with the wrapper, wherein the step of applying adhesive to the wrapper comprises applying adhesive over a width of the wrapper and in a central longitudinal portion of the wrapper, and comprises applying the adhesive in several strips over a length of the wrapper.   
     
     
         2 . Method according to  claim 1 , comprising the step of guiding the substantially flat continuous material between electrode and counter electrode of a corona module. 
     
     
         3 . Method according to  claim 1 , corona treating the substantially flat continuous material during a treatment time in a range between 0.001 seconds and 2 seconds. 
     
     
         4 . Method according to  claim 1 , comprising the step of corona treating one side of the substantially flat continuous material and subsequently corona treating the other side of the substantially flat continuous material. 
     
     
         5 . Method according to  claim 1 , wherein a strip of adhesive is applied along the longitudinal central axis of the wrapper. 
     
     
         6 . Method according to  claim 1 , wherein several strips are arranged in parallel. 
     
     
         7 . (canceled) 
     
     
         8 . (canceled) 
     
     
         9 . Method according to  claim 1 , wherein the substantially flat continuous material is a plastics material, for example polylactic acid. 
     
     
         10 . Method according to  claim 1 , applying one type of adhesive to the central longitudinal portion of the wrapper and another type of adhesive to a seam portion of the wrapper. 
     
     
         11 . Consumable comprising a segment of a wrapped endless rod manufactured according to the method according to  claim 1 . 
     
     
         12 . (canceled) 
     
     
         13 . Apparatus for manufacturing a wrapped endless rod of substantially flat continuous material, wherein the apparatus is programmed to perform the method according to  claim 1 , the apparatus comprising:
 a rod-forming unit for shaping a substantially flat continuous material into an endless rod;   a wrapping device for providing a wrapper and for wrapping the endless rod with the wrapper;   an adhesive applicator for applying an adhesive to the wrapper, wherein the adhesive applicator is arranged for applying adhesive to a central portion of the wrapper;   a corona module arranged upstream of the rod-forming unit for corona treating the substantially flat continuous material.   
     
     
         14 . Apparatus according to  claim 13 , wherein an electrode of the corona module has a lateral size corresponding to a width of the substantially flat continuous material to be corona treated. 
     
     
         15 . Apparatus according to  claim 13 , wherein a distance between electrode and counter electrode is in a range between 0.1 millimeter and about 25 millimeter. 
     
     
         16 . Apparatus according to  claim 13 , wherein the corona module comprises a first module portion and a second module portion, the first module portion and the second module portion each comprising an electrode-counter electrode pair, wherein the electrode-counter electrode pair of the first module portion is arranged and powered to enable corona treatment of one side of the substantially flat continuous material and the electrode-counter electrode pair of the second module portion is arranged and powered to enable corona treatment of the other side of the substantially flat continuous material. 
     
     
         17 . Apparatus according to  claim 16 , wherein at least one module portion comprises two electrodes arranged next to each other in a transport direction of the substantially flat continuous material. 
     
     
         18 . Apparatus according to  claim 13 , wherein the corona module comprises a high frequency generator for providing frequencies in a range between 10 kHz and 60 kHz and an alternating voltage between 15 kV and 40 kV.