Apparatus for aspirating precise volumes of fluid sample

Abstract

Abstract APPARATUS FOR ASPIRATING A PREDETERMINED VOLUME OF LIQUID SAMPLE FROM A CONTAINER INTO A INTAKE CONDUIT, TOGETHER WITH A QUANTITY OF DILUENT HAVING PREDETERMINED VOLUMETREIC RATIO TO THE SAMPLE VOLUME. A VERTICALLY RECIPROCABLE SAMPLING PROBE IS PROGRAMMED TO ASPIRATE SAMPLE UNTIL THE LEADING EDGE OF THE SAMPLE REACHES A SENSOR IN THE RECIPROCATE INTO A DILUENT CHAMBER AND ASPIRATES DILUENT FOR A PRESET TIME. THEREAFTER THE SAMPLER MOVES INTO AIR AND ASPIRATES AN AIR VOLUME EQUAL TO THE SAMPLE VOLUME. THE PROBE IS THEN REINSERTED IN THE DILUENT, AGAIN FOR THE PRESET TIME AND THEREAFTER AGAIN ASPIRATES THE PRECISE VOLUME OF AIR. IN THE FINAL STEP THE SAMPLER IS AGAIN INSERTED INTO THE DILUENT CHAMBER TO ASPIRATE UNTIL THE LEADING EDGE OF THE SAMPLE REACHES A SECOND SENOR POSITIONED TO DEFINE A VOLUME BETWEEN IT AND THE SAMPLER ORIFICE, SUCH THAT THE DILUENT ASPIRATED HAS A KNOWN RATIO TO THE PRECISE VOLUME OF SAMPLE. A DOWNSTREAM AIR INTAKE IS ACTUATED EACH TIME THE SAMPLER IS MOVED INTO AIR TO INSERT SUFFICIENT AIR AHEAD OF THE FLUID COLUMN TO PREVENT UNDUE ACCELERATION OF THE FLUIDS IN THE CONDUIT.

Inventors

• 👤 J Bannister
• 👤 F Coller
• 👤 Santis I De

Bibliographic Details