INTERMITTENT DROP DETECTING METHOD AND APPARATUS

摘要

Improved fluid drop detection method and apparatus. The invention is contemplated specifically for use in the administration of parenteral solutions to patients in hospitals and the like, but it also can be utilized for detecting and controlling drop flow of any liquid in precise quantities over a desired period of time into chemical or biological reactors, industrial processes, and the like. In accordance with the present invention, a method and apparatus is provided to precisely monitor the drop flow rate from a fluid source. The invention allows for variations in the drop flow rate by accumulating a weighted rate error factor which can be adjusted by each drop period detected. Preferably each drop period or interval is compared against both a slow rate limit and a fast rate limit. The limits are set proportional to the previous drop period. The accumulated total is compared to an error threshold, which is set to ignore minor fluctuations in a number of consecutive drip periods. The accumulated total also can be averaged over a multiple number of drop periods by adding an error factor foreach drip period which is outside of the limit and subtracting an error factor for each drip period which is within the limit.