Numbering throw-off for collator

Abstract

A low-cost, completely self-contained numbering unit for in-line web collators is provided which includes fully mechanical throw-off apparatus for selectively activating and deactivating the unit in a manner ensuring proper sequential numbering of forms or the like, notwithstanding intermittent temporary interruptions of web flow through the unit. The numbering unit hereof preferably includes a plurality of rotatable numbering machines each having an indexing arm, a pivotal cam engageable with the respective arms and shiftable between indexing and non-indexing positions, and control means for allowing such cam shifting only under circumstances ensuring maintenance of proper numbered sequence between forms or the like as they are produced. The control means preferably includes a rotatable, recessed control cam coupled to the numbering machine mounting shaft, along with a cooperating projection extending from a shiftable plate coupled to the indexing cam shaft; movement of the plate in a manner to pivot the indexing cam between the indexing and non-indexing positions thereof is thus precluded unless the control cam is rotated to a position permitting clearance of the plate projection therepast. The indexing cam is thus movable only when the numbering machines of the unit are in respective preset rotational position so that misnumbering of the forms is prevented. The plate is operated by means of a manual control knob, and is provided with biasing springs and limit means for facilitating smooth, measured movement thereof so that the indexing cam can be quickly and accurately shifted.