Pipette

Abstract

A pipette includes a cylinder having a distal end portion to which a pipette tip is removably fitted; and a piston fitted to be freely advanced and retreated in a cylinder chamber. The piston is retreated to suck liquid and advanced to eject the liquid thus sucked. The piston includes, on an outer periphery thereof, a communication groove for allowing an inside of the cylinder chamber to communicate with an outside of the cylinder chamber when the piston is advanced by an amount corresponding to a dimension larger than a predetermined dimension. The communication groove is located on the outside of the cylinder chamber when the piston is located at a retreated position. When the piston is advanced by the amount corresponding to the dimension larger than the predetermined dimension, a seal between the cylinder chamber and the piston is released so that pressure in the cylinder chamber becomes equal to the atmospheric pressure, and a suction/ejection effect is eliminated.

Dependencies are inferred from the claim text.