A pipetting device for detachably mountable pipette tips, comprising a moving
device,
a piston movable by the moving device in a cylinder to displace a column of air,
an attachment stem for mounting a pipette tip, with an aperture having a connection
to the cylinder at the free end, two stops limiting the movement of the piston
during the displacement of the column of air, one of which is dislocatable, a precise
adjustment device for dislocating the dislocatable stop in parallel with the piston
for a precise adjustment of the piston stroke, a coupling device which puts the
precise adjustment device into function, when coupled, and puts it out of function,
when uncoupled, a rough adjustment device for dislocating the dislocatable stop
when the precise adjustment device is uncoupled, for a rough adjustment of the
piston stroke, and a measuring and indicating device coupled to the dislocatable
stop for measuring the position set for the dislocatable stop and indicating the
proportioning volume that matches the piston stroke set.
