Abstract: An automatic machine for perforating and comb binding blocks of loose sheets. The control of the movements of the punching and binding mechanisms is centralized. The machine is capable of making perforations and thus bindings which are either continuous or in the form of portions separated in a manner which can be preset as desired. Feed of the sheets to be perforated and bound is effected by chains provided with fixed brackets with corresponding movable tabs which can withdraw into or project out of the conveying surface. The movement of the tabs is coordinated with that of the chains and of the punching mechanism. The feed of the comb binding to the coupling station is effected by two independent brake-friction units, controlled separately by presettable digital controls.