Rider roll relieving system

In a rider roll relieving system including

• a pair of winding drums,
• a core on which a web is wound with the aid of the winding drums,
• a rider roll for applying pressure to the core, and the web as it is wound on the core, to control the internal tension of the web, and
• means for controlling the pressure applied by the rider roll to the web,
• the improvement comprising,
• means for sensing the diameter of the web as it is wound onto the core,
• means for selecting a first diameter where rider roll relieving action is to be commenced,
• means for selecting a maximum rider roll pressure,
• means for setting a second, larger diameter where rider roll relieving action is to be terminated,
• means for setting a minimum rider roll pressure to be maintained after the relieving action is terminated,
• means for providing control signals to said rider roll pressure controlling means for providing a pressure relieving action by controlling the rider roll pressure as a function of the diameter of the web to provide continuous rider roll pressure reduction as the web is wound between said first diameter and said second diameter while maintaining said maximum rider roll pressure until said first diameter is reached and maintaining said minimum rider roll pressure after said second diameter is reached.