Method and apparatus for producing corrugated cardboard

Abstract

A method and apparatus for applying adhesive to the flutes of corrugated board to bond a face thereto. An applicator roll is provided with a uniform thin coating of adhesive by a flexible bar urged toward the surface of the applicator roll. A rider roll is provided adjacent the applicator roll and at the same height to form a vertical space for passage of the board therebetween so that the amount of glue applied to the tip of the flutes is directly proportional to the speed of the applicator roll. The space between the applicator roll and the rider roll is precisely controlled to minimize the amount of crush or deformation of the flutes during the application of the adhesive thereto. The dwell time in which the flutes are in contact with the adhesive layer on the applicator roll is reduced by minimizing the size of the rider roll and wrapping the face substantially around the rider roll. The applicator roll is driven at a speed substantially less than the speed of the rider roll to reduce the amount of adhesive applied to the tip of the flutes. Therefore, the speed of the applicator roll can be automatically adjusted to control the amount of adhesive applied to the tip of the flutes.