Abstract

The invention is concerned with controlling fluid delivery by a fluid dispensing system in which fluid is dispensed from a container, through a delivery tube, under the control of a flow controller or peristaltic pump and, particularly, with the control of the rate of fluid delivery to a patient by an intravenous infusion system utilizing a standard administration set. The control apparatus continually monitors the weight loss of the fluid container, as fluid is dispensed, and produced data identifying the actual fluid delivery rate. It compares this data with a signal identifying the selected delivery rate and provides for adjustment of the flow controller or pump so as to conform the actual delivery rate to the selected rate. Because weight signals for computing the actual delivery rate are not immediately available upon initiation of a dispensing operation, the selected rate signal is initially processed by the apparatus to produce data for setting the flow controller or pump speed to a value nominally corresponding to the selected delivery rate so that the the actual delivery rate is controlled as accurately as possible from the start of the dispensing operation.