Method and apparatus for tier forming on a row by row basis

Abstract

In a palletizer, various load patterns are achieved through the arrangement of tiers or layers of rows of cartons, each constituent row therein having a given width. Conveying means are provided with a first side at which rows of cartons are received at spaced intervals and a second side. The conveying means, when actuated, is effective to transport the rows of cartons thereon towards the second side thereof. Means, responsive to the number of rows of cartons present on the conveying means, is effective, subsequent to the entry of each of the incoming rows of cartons at the first side of the conveying means, to actuate the conveying means to transport the rows presently thereon a distance substantially equal to the width of the incoming row, when less than R rows are present on the conveying means, and a selected distance sufficient to move the leading row of cartons on the conveying means to the second side thereof, when R rows are present thereon. This method of row formation prevents skewing of the cartons as is common with conventional tier forming methods and, in addition, gaps between cartons in adjacent rows can be preserved without the necessity for stop means. Actuatable stop means are provided at various positions along the conveying means. The rows of cartons can, where not being formed by the above method, be advanced to an actuated stop means or, alternatively, to an end stop at the second side of the conveyor means in order to provide additional versatility in tier formation.