Report and analysis of the 2006 post - election audit of Minnesotas voting systems

A punching apparatus comprising a C-shaped frame having a first movable punch disposed in one limb of the frame and a second fixed punch disposed in the other limb of the frame. The frame is pivotally mounted on a supporting base and is guided relative to the base through a cylindrical column connected to the base which is mounted in a bore of the frame, which bore extends parallel to the direction of the punches. A further support is provided for guiding the frame including a stud which is secured to the frame, which stud extends into a slot in the supporting base.