a mechanical means for unwinding paper sheet , plastic film or other thin films from heavy storage rolls . the device includes a normal unwind pair of squeeze rolls which grip the film on opposite surfaces and propel the film toward a use area . a friction roll is positioned on the periphery of the storage roll but normally runs free and is not coupled to a power means . when the mechanism is accelerating , as in a starting operation , power is applied to the friction roll to aid in its speed - up . when the mechanism is decelerating , as in a stopping operation , power is applied to the friction roll to aid as a brake . auxiliary pressure means may be provided to increase the contact pressure between the friction roll and the storage roll to prevent slipping .