Patent ID: 6168305
Filing Date: 2001-01-02
Classification: G01G

Abstract:
A system for controlling the amount of material discharged from a feeder comprising: a weight scale for measuring the weight of a supply of material being discharged from a feeder; a digital processor for periodically sampling a signal from said weight scale, and digitizing said signal; digital filter means for filtering said digitized signal, and providing an array of continuously updated average weight values, including an oldest and newest average weight values which are a moving average of said digitized signal; means for providing a desired digital weight loss signal over the time interval represented by average weight values of said array obtained only when the weight loss is constant and stable; means for providing a loss in weight signal based upon said array of average weight loss values; means for deriving an error signal based upon said loss in weight signal and said desired weight loss signal; second digital filter means for providing an average of a plurality of said error signals; and, means for providing a proportional integral control signal in response to said error signal for controlling the discharge rate from said feeder.