Hand-held micropipettor with fluid transfer volume adjustment mechanism

摘要

A micropipettor having an adjustable stop threadedly engaged with an internal reciprocal plunger assembly for defining the stroke length of the plunger and thus of a fluid displacing piston that is attached to the plunger assembly. The adjustable stop is manipulated by operable connection with a volume adjustment knob provided on the outside of the micropipettor body. The plunger carries a coarse volume indicating scale and the volume adjustment knob is provided with a fine volume setting scale. Accidental changes in volume adjustments are avoided by two types of automatic locks: a frictional engagement of the internal volume adjustment mechanism unless the plunger is deliberately placed in a certain position by the operator, and a detent lock of the volume adjustment knob unless the operator deliberately depresses it.