Document shredding machines

Claim 1

A document shredding machine of the kind comprising a machine frame, two cutter assemblies each comprising a shaft mounted on the frame and cutter discs mounted on the shaft at spaced intervals, the shafts being substantially parallel and spaced apart a distance such that the discs on one shaft extend into the spaces between the discs on the other shaft into overlapping relationship and form a nip, the machine comprising drive means mounted on the frame which is operative to rotate the shafts in opposite directions so that documentary material fed into the nip of the machine is cut into strips by the action of the overlapping discs, the improvement wherein one of the cutter assemblies is mounted so as to be capable of separative movement relative to the other cutter assembly against the action of resilient means, the machine including stop means on the machine frame which may be moved between a stop position in which it maintains the two cutter assemblies in prefixed overlapping relationship and prevents such relative separative movement and a release position in which such relative separate movement against the action of the resilient means is permitted, said stop means when in its release position limiting the separative movement to an extent so as to maintain the cutter discs of the two assemblies in said overlapping relationship.