APPARATUS FOR COMPENSATING THERMAL EXPANSION IN A CUTTING MACHINE

摘要

A cutting apparatus for cutting a web or sheet material is arranged to compensate for the effects of thermal expansion of parts of the apparatus which occurs during use of the apparatus. The cutting apparatus comprises a rotary knife (14) which carries a plurality of knife elements (18) and a suction drum (10) which carries a plurality of counter-knives (19). The counter-knives cooperate with the knife elements to sever the material as it passes between them. The rotary knife and suction drum are mounted on a frame (22). The rotary knife is mounted to the frame via a plate (24). The frame and the plate are arranged to compensate for variations in a desired relationship between the knife elements and the counter-surfaces caused by thermal expansion occurring during use of the apparatus so that the desired relationship is maintainable.