Paper Stack Quality Improvement

How do you make paper stack neatly in a printer output bin without a paper bail? I thought this question sounded simple and almost negligible when I first heard it. I was wrong on both accounts.

Let me address the negligible theory first. After further pondering, I recalled my days in grad school as a teacher. It was extremely annoying to print off a large stack of papers only to have to knock the stack against a table to try and straighten it out so it could fit in my backpack. And most of the time I was in a hurry and ended up with either a paper cut or some raggedy handouts. I have the feeling I am not the first person to be in this situation.

Now let me discuss the simple theory. Nothing about paper is simple because it is a composite material and highly reactive to moisture. Paper coming out of a laser printer, therefore, can end up quite curled and the curl can vary from sheet to sheet and especially between types of paper. All this is complicated in its own right, but throw in a relatively high velocity and you have yourself a whole new set of issues.

The first step for me was research. What has been done before, and not just by this company, but by our competitors as well? It quickly became apparent that no measurement system existed and without one experimentation was meaningless. After a measurement system was created and validated, and key features in the various designs were determined, several experiments ensued. Several prototypes, statistical analysis, iOptimal designs, and an FMEA (failure modes and effects analysis) later, the final solution improved stack quality by 90%.