HAND HELD PIPETTE WITH DISPOSABLE CAPILLARY

摘要

A hand-held manually operated pipette having an adjustable plunger stroke and calibrated electronic digital volumetric display draws-up and dispenses viscous, dense or high vapor pressure liquids by means of an easily replaced, disposable, integral, positive displacement type plunger tip and capillary assembly. The pipette in another form utilizes a disposable air displacement capillary. The plunger adjustably strokes to a first stop in a first mode for calibration or sample draw-up and dispensing with the volume of pipette liquid contents continuously displayed. In a second mode an over-travel arrangement enables the plunger shaft to stroke beyond the first stop to permit collet type attachment and ejection of the integral plunger tip and capillary for positive displacement service or to eject an air displacement capillary.