System to align and square boxes

Abstract

A system for aligning and squaring folded and glued boxes being conveyed serially in line or in a shingle utilizes a fixed set of alignment wheels positioned parallel to and on one side of the shingle and a set of adjustable alignment wheels positioned on the opposite lateral edge of the shingle. The adjustable alignment wheels can be adjusted as a unit to pivot on a vertical axis and to move laterally slightly into the path of the shingle. The pivot arm on which the adjustable wheels are mounted accommodates major misalignment of the initially incoming shingle, but is pivoted to an aligned position in the direction of shingle movement by the force of the moving shingle. Return of the pivot arm to the aligned position activates an air cylinder to move the alignment wheels laterally into the edge of the shingle with a force sufficient to move the boxes into engagement with the fixed alignment wheels on the opposite side, thereby providing complete edge registration of the boxes in the shingle and simultaneously squaring any boxes which may have become out of square before the glue has dried. The registration system is positioned immediately upstream of a rotary slitting blade into which the shingle is conveyed. A secondary alignment mechanism of substantially shorter length, but operating similarly to the primary upstream mechanism, helps retain accurate alignment during slitting. Spring biased holddown strips are positioned above the shingle to provide a vertical holddown force, which force progressively increases in a downstream direction to allow easy lateral movement of the boxes in the main registration mechanism, but a greater holddown force at the slitting blade.