To smoothly take up a steel plate by surely fastening its front edge to a take-up roll when the steel plate is taken up.

When a sliding shaft 461 is moved forward/backward via a sliding cylinder, an engaging element 463X supported by a slanting face 462a of a wedge member 462 being installed to the sliding shaft 461 moves up/down along a guide hole 463b of an engaging member 463 for pressing or separating from a linear 464 being installed at a tip end part inner peripheral face of a movable side dram 44. As a result, the movable side dram 44 rotates against a fixed side dram for forming a clearance on the roll element, into which a steel plate can be inserted, or closing the clearance. In this case, since the weight of the steel plate being taken-up by the roll element 4 acts in a radial direction of the sliding axis 461, it does not curtail the sliding cylinder, and a clearance is not formed on the take-up roll element 4 when the steel plate is taken up.