Paper sheets punching apparatus

Abstract

A paper punch and binding apparatus has two punch mechanisms, one for punching round holes in a paper sheets stack and one for punching rectangular holes in another paper sheets stack. A single lever or crank simultaneously operates and drives a series of round end punches to shear the round holes and a punch plate with integral rectangular punch elements shear rectangular holes. A four-bar linkage connects the lever to the punch plate and the series of the punches in a manner that both the plate and punches are driven in a vertical straight line and with a greater mechanical advantage at the start and over the first increments of the punching operation. In a preferred embodiment, a binding station is provided in an apparatus base portion particularly for binding with a Douvry-type plastic resilient loops binding element. The binding station has an operating knob which operates a simple gear interconnect train for uncurling the resilient loops and allowing the punched hole stack to be inserted thereon. In an additional embodiment two rows of large and smaller diameter punches are provided in one round punch mechanism with an apertured translatable bar for rendering inoperative one or the other of these rows of punches.