| 摘要 |
1. Process for metering small quantities of liquid without leaving a residue by means of a micro-piston pump having a capillary cylinder in which a piston, which fits in gastight manner therein, is mounted so as to be movable between a top dead centre and a bottom dead centre, the cylinder at its end located opposite the base of the piston opening into a twoway valve which connects the space in the cylinder alternately to an inlet and to an outlet (which connects the cylinder to the atmosphere during the first stage of the intake operation), characterised in that the piston and the valve are moved in such a way that, during the intake operation, first a defined quantity of air and then a defined quantity of liquid is transported into the cylinder, the quantity of air being such that, as the piston moves downwards to bottom dead centre, all the liquid is expelled through the outlet line. |
