Perforating device

Claim 1

A DEVICE FOR PERFORATING SHEET MATERIAL AND FOR INSERTION IN A RING BINDER, INCLUDING IN COMBINATION, A METAL PUNCH HAVING UPPER AND LOWER PLATES, SAID LOWER PLATE HAVING A SINGLE PROJECTION THEREON AND SAID UPPER PLATE HAVING A CORRESPONDING PUNCH OPENING THEREIN FOR PERFORATING SHEETS INSERTED THEREBETWEEN, A HINGE MEANS JOINING SAID UPPER AND LOWER PLATES, A SUBSTANTIALLY FLAT PLASTIC CARRYING MEMBER HAVING A MOUNTING SURFACE FOR SAID PUNCH, MEANS FOR STAKING SAID LOWER PLATE TO SAID MOUNTING SURFACE, SAID CARRYING MEMBER HAVING HINGE HOUSING MEANS INCLUDING A RECESS THEREIN FOR ACCOMMODATING SAID HINGE MEANS, SAID MEMBER HAVING A MOUNTING EAR WITH AN OPENING THEREIN FOR MOUNTING THE DEVICE IN A RING BINDER AND A RAISED SHOULDER HAVING A CHANNEL THEREIN AND SURROUNDING SAID MOUNTING SURFACE THEREBY PROHIBITING CONTACT OF SAID UPPER AND LOWER PLATES, AND SPRING MEANS BEING POSITIONED BETWEEN SAID LOWER PLATE AND SAID MOUNTING SURFACE AND EXTENDING THROUGH SAID CHANNEL OF SAID SHOULDER, MEANS INCLUDING SAID LOWER PLATE FOR SECURING SAID SPRING MEANS TO SAID CARRYING MEMBER, SAID SPRING MEANS BEING COMPRESSED WHEN SAID PLATES ARE MOVED IN PERFORATING POSITION, SO THAT UPON RELEASE OF SAID PLATES SAID SPRING MEANS ACTS TO RETURN SAID UPPER PLATE TO A NON-PERFORATING POSITION RELATIVE TO SAID LOWER PLATE AND CLEARS THE SHEET MATERIAL FROM SAID PUNCH PROJECTION.