Precision Fluid Dispensing Using Peristaltic Roller Control

摘要

A precision fluid dispensing system that can be effectively used for accurate fluid dispensing in peristaltic pumps if roller control is used. Peristaltic pumps can be combined with pinch valves allowing a dispense tube to be open while a source tube is blocked. Controlled roller movement is used to move the next roller to the same starting position as the previous roller was on the previous dispense, the dispense pinch valve is closed and the source valve is opened. The system uses roller positioning where the each roller is properly positioned so that each dispense cycle starts in the same position. The precision and accuracy is better than 0.3% total.

主权项

1. A precision fluid dispensing system comprising:
a peristaltic pump with a plurality of rollers on at least one rotor configured to execute a sequence of single dispenses; a motor driving the rotor; an encoder or external sensor cooperating with said rotor, the encoder or external sensor adapted to determine an absolute rotational position of the rotor; wherein, after each single dispense in said sequence of single dispenses, the motor positions the rotor so a next roller is in an identical angular position as a previous roller before the dispense.