a strip , such as paper in a printing mechanism , is transported over a friction roll either along a first path , in which the paper is driven by rotation of the friction roll by a drive motor through an overrunning clutch ; or along a second path in which the paper passes over the friction roll and is taken up on a take - up roll , the pull of the strip onto the take - up roll causing the friction roll to rotate faster and disengaging the clutch . two strips may be passed through a nip between the friction roll and a pressure roll . the pressure roll is driven by coupling to the friction roll so as to have a slightly higher circumferential velocity .