Printing web system

Abstract

A web system, such as a printing web system, having reduced power consumption is disclosed. Power consumption is reduced by joining the unwind and rewind shafts of the web system together through a continuously variable transmission (CVT). The CVT allows the unwind and rewind rolls to provide torque to each other as well, allowing fewer drive motors and/or drive motors of smaller size to be used in the web system.

1 . A web system that provides tension with reduced power consumption, comprising:
 an unwind shaft, a rewind shaft, and a processing system;   a drive path running from the unwind shaft through the processing system to the rewind shaft;   a drive motor located along the drive path; and   a continuously variable transmission comprising a first shaft and a second shaft, the first shaft and second shaft being connected to each other through a power transfer linkage;   wherein the first shaft is connected to the unwind shaft and the second shaft is connected to the rewind shaft.   
   
   
       2 . The web system of  claim 1 , wherein the continuously variable transmission is a variable diameter pulley system. 
   
   
       3 . The web system of  claim 1 , wherein the continuously variable transmission is a toroidal transmission system. 
   
   
       4 . The web system of  claim 1 , wherein the continuously variable transmission is a hydrostatic transmission system. 
   
   
       5 . The web system of  claim 1 , wherein the drive motor is located at the unwind shaft. 
   
   
       6 . The web system of  claim 1 , wherein the drive motor is located at the rewind shaft. 
   
   
       7 . The web system of  claim 1 , wherein the drive motor is a drive nip. 
   
   
       8 . The web system of  claim 1 , further comprising a web differential velocity measurement system. 
   
   
       9 . The web system of  claim 8 , wherein the web differential velocity measurement system comprises a dancing roll and a position sensor. 
   
   
       10 . The web system of  claim 8 , wherein the web differential velocity measurement system comprises a stationary roll and a tension sensor. 
   
   
       11 . The web system of  claim 1 , wherein the processing system comprises a printing press. 
   
   
       12 . A web system that provides tension with reduced power consumption, comprising:
 an unwind shaft, a rewind shaft, and a processing system;   a drive path running from the unwind shaft through the processing system to the rewind shaft;   a drive motor located along the drive path;   a tension measurement system located along the drive path; and   a continuously variable transmission comprising a first shaft and a second shaft, the first shaft and second shaft being connected to each other through a power transfer linkage;   wherein the first shaft is connected to the unwind shaft and the second shaft is connected to the rewind shaft.   
   
   
       13 . The web system of  claim 12 , wherein the continuously variable transmission is a variable diameter pulley system. 
   
   
       14 . The web system of  claim 12 , wherein the continuously variable transmission is a toroidal transmission system. 
   
   
       15 . The web system of  claim 12 , wherein the continuously variable transmission is a hydrostatic transmission system. 
   
   
       16 . The web system of  claim 12 , wherein the drive motor is located at the unwind shaft. 
   
   
       17 . The web system of  claim 12 , wherein the drive motor is located at the rewind shaft. 
   
   
       18 . The web system of  claim 12 , wherein the drive motor is a drive nip. 
   
   
       19 . The web system of  claim 12 , further comprising a web differential velocity measurement system. 
   
   
       20 . A method of reducing the power consumption of a web system, comprising:
 providing a web system comprising an unwind shaft, a rewind shaft, and a processing system; and   connecting the unwind shaft and the rewind shaft to a first shaft and a second shaft of a continuously variable transmission.