A system is provided for braking rotational movement comprising: a rotatable member; a friction surface disposed on the rotatable member; a friction plate opposed to the friction surface, such that when the rotatable member rotates the friction plate is in contact with the friction surface; a rod, having at least a threaded portion, and the at least a portion of the rod being received within the rotatable member such that the rotatable member rotates about the rod and moves along the threaded portion towards the friction plate; and a compressive member, whereby a force is applied to the friction plate which increases with rotation of the rotatable member.