High production folder construction

A folding apparatus comprising conveyor means for moving foldable articles along a path of movement;

• first and second air discharge means disposed adjacent the path of movement for discharging air in sequence over a portion of the moving conveyor means;
• said air discharge means defining a folding field over said conveyor means for folding opposed first and second portions of each of such foldable articles over an intermediate portion of each such foldable article on said conveyor means;
• such foldable articles having a length not greater than that of said folding field;
• means for measuring the size of each foldable article conveyed on said conveyor means and entering said folding field;
• means for controlling the folding of the opposed first and second portions of each such foldable article, said means for controlling being responsive to said measuring means for calculating the distance of travel of each such foldable article moving at the speed of said conveyor means;
• and means for stopping said conveyor means with the leading edge of such foldable article thereon at the end of said folding field when the combined length of such foldable article and its fold-completing distance of travel amounts to a length sum which exceeds the length of said folding field, said stopping means being responsive to said controlling means.

A method for forming French folds in foldable articles by means of opposed air discharge means which operate in sequence to fold opposed first and second panels of a foldable article over an intermediate panel portion and defining a folding field through which foldable articles are conveyed;

• portions of a first and second foldable article being simultaneously within such folding field;
• the steps comprising measuring the size of the first article entering the folding field;
• folding a first and second panel of the first article by first and second sequential air discharges of the opposed air discharge means;
• measuring the size of the second article entering the folding field and the distance the second article must travel in the field until the second air discharge occurs on said second article;
• calculating the distance the first article travels to exit the folding field when the second article is completely measured;
• and folding a first panel of the second article by the air discharge means which folded the second panel of the first foldable article.

In a method for forming folds in foldable articles by means of opposed air discharge means which operate in sequence to fold opposed first and second panel portions of a foldable article over an intermediate panel portion;

• said discharge means defining a folding field through which foldable articles are conveyed by a conveyor at a speed which prevents sequential folding of the opposed panels of a foldable article within the folding field without stopping of the conveyor;
• such articles having a length no greater than that of the folding field;
• the steps comprising measuring the size of a foldable article entering the folding field and the time for such article to enter the folding field on the conveyor;
• calculating the distance the article must travel in the folding field on the conveyor to complete the folding of the panel portions;
• and stopping the conveyor travel with the article in the folding field for the sum of the time of article travel in the folding field to complete the folding of the panel portions plus the time of article travel in entering the folding field, less the time of article travel on the conveyor to pass through the entire folding field.