Patent ID: 8191340

Claim:
A web supply arrangement for use with packaging machine that uses web material, the arrangement comprising: a roll having web material wound around a hollow core; a mandrel adapted to be received within the hollow core of the roll and configured to support the web material; a variable speed advancement arrangement engaged with the web material, wherein the variable speed advancement arrangement includes a web engagement mechanism that advances the web material through the packaging machine in a cyclic intermittent motion indexing manner; an inflatable device associated with the mandrel, wherein the inflatable device is selectively inflatable to brake rotation of the roll and to thereby control the tension of the web material as the web material is unwound from the roll of web material during cyclic indexing advancement of the web material through the packaging machine; a pump for selectively inflating the inflatable device; and a controller interconnected with the pump and responsive to the variable speed advancement arrangement, wherein the controller is operable to control a pressure in the inflatable device in response to the variable speed advancement arrangement, wherein operation of the controller to control pressure in the inflatable device functions to cooperate with the variable speed advancement arrangement to control tension of the web material between the roll and the web engagement mechanism and to vary tension in the web material within each cycle of movement of the web material caused by the variable speed advancement arrangement.