Method for wrapping plastic film on a load and wrapping machine

Abstract

A method and wrapping machine for wrapping a plastic film web from at least one roll on a load with a wrapping machine, wherein the location of the at least one roll of plastic film web in relation to at least the height of the load to be wrapped is detected and monitored during wrapping, one or a plurality of points or locations along the height of the load to be wrapped are preset before starting of the wrapping, at which preset points or locations and/or between said preset points or locations the wrapping characteristics are changed during wrapping.

1 - 12 . (canceled) 
     
     
         13 : A method for wrapping a load with a plastic film web from a roll using a wrapping machine, said method comprising:
 during wrapping of the plastic film web on the load, monitoring the plastic film web in relation to a height of the load being wrapped, wherein a location along the height of the load is preset before starting of the wrapping, said preset location being above a bottom of the load and below a top of the load; and   responsive to detecting that the plastic film web reaches the preset location along the height of the load, changing at least one wrapping characteristic of the wrapping of the plastic film web on the load.   
     
     
         14 : The method of  claim 13 , wherein said at least one wrapping characteristic includes at least one of: a wrapping height, a number of plastic film web layers wrapped, a tension of the plastic film web, a wrapping speed, an amount of overlap of subsequent wrapping rounds, and an overlap tension. 
     
     
         15 : The method of  claim 14 , which includes enabling an operator to set said preset location using a user interface prior to starting of the wrapping of the load. 
     
     
         16 : The method of  claim 14 , which includes enabling an operator to set said at least one wrapping characteristic prior to starting of the wrapping of the load. 
     
     
         17 : The method of  claim 13 , which includes enabling an operator to set said preset location using a user interface prior to starting of the wrapping of the load. 
     
     
         18 : The method of  claim 13 , which includes enabling an operator to set said at least one wrapping characteristic prior to starting of the wrapping of the load. 
     
     
         19 : The method of  claim 13 , wherein the wrapping includes rotating the plastic film around the load while the load is stationary. 
     
     
         20 : The method of  claim 13 , which includes pre-stretching the plastic film web before wrapping the plastic film web around the load. 
     
     
         21 : A wrapping machine for wrapping a plastic film web from a roll on a load, said wrapping machine comprising:
 a first device for detecting and monitoring the location of the roll of plastic film web in relation to a height of the load to be wrapped during wrapping;   a second device for defining at least one preset location along the height of the load above a bottom of the load and below a top of the load; and   a third device for changing at least one wrapping characteristic responsive to the plastic film web reaching the preset location along the height of the load.   
     
     
         22 : The wrapping machine of  claim 21 , wherein said devices comprise at least one processor and at least one memory including computer program code, wherein the program code is configured to, when executed by the at least one processor, cause the at least one processor to control the motors of the wrapping machine moving the roll of plastic film web in relation to the load to be wrapped and a motor for feeding the plastic film web. 
     
     
         23 : The wrapping machine of  claim 22 , wherein the computer program code is configured, when executed by the at least one processor, to cause the at least one processor to control the at least one wrapping characteristic during the wrapping so that at least one of a wrapping height changes, a number of wrapped plastic film web layers changes, a tension of the plastic film web changes wrapping speed changes, an amount of overlap of subsequent wrapping rounds changes, and an overlap changes. 
     
     
         24 : The wrapping machine of  claim 21 , wherein the first device for detecting and monitoring the location of the roll of plastic film web in relation to the height of the load to be wrapped during wrapping comprises an encoder arranged in connection of a motor moving the roll of plastic film in a vertical direction and a photocell. 
     
     
         25 : The wrapping machine of  claim 21 , which includes an automatic control system for controlling the wrapping machine and said devices with a user interface for setting the preset location. 
     
     
         26 : The wrapping machine of  claim 21 , which includes an automatic control system for controlling the wrapping machine and said devices with a user interface for setting the wrapping characteristic. 
     
     
         27 : The wrapping machine of  claim 21 , which includes a device for rotating the one roll of plastic film web around a stationary load. 
     
     
         28 : The wrapping machine of  claim 21 , which includes a device for pre-stretching the plastic film.