| 摘要 |
<p>In an apparatus for the pulsewise dispensing of very small amounts of liquid controlled with a measuring instrument comprising an ejecting device for the pulsewise ejection of a desired amount of liquid, a pump is provided for supplying liquid to the vessel from a reservoir. The pump includes a neck portion having an inlet at the bottom thereof and a foot portion, with at least the foot portion immersed in a liquid contained in the reservoir. The foot portion has a volume at least as great as the refill volume of the measuring vessel and a feedline to the measuring vessel is disposed within the neck portion and terminates in proximity to the bottom of the foot portion. A check valve opens and closes the foot portion inlet by means of compressed gas which is controllable by sensing devices at the measuring vessel.</p> |
