FLUID DISPENSE AND LIQUID SURFACE VERIFICATION SYSTEM AND METHOD

摘要

A sensor for detecting contact of a fluid delivery probe with a fluid surfac e and for detecting fluid flow through the probe includes a first electrode disposed along a fluid flow path of the probe upstream from a distal tip of the probe and a second electrode longitudinally spaced and electrically isolated from the first electrode and disposed at the distal tip of the prob e. An oscillating signal is transmitted through the first electrode, and at lea st a portion of the signal is received through the second electrode. Through changes in the received signal due to the distal tip of the probe coming int o contact with a fluid surface or due to fluid flow through the conduit betwee n the first and second electrodes, fluid surface contact and fluid flow can be detected. A pressure sensor can be employed to monitor internal fluid pressu re within the fluid conduit of the fluid delivery probe as a secondary, redunda nt means for detecting fluid flow through the conduit.