| 摘要 |
<p>Automatic pump with liquid piston comprises a compression cylinder provided with a non-return clappet valve linked to a vacuum and a second similar valve linked to a higher pressure source. A cylinder provided with a tube at its lower end, which tube passes to the bottom of a vessel which is partly filled with mercury. A tubular side-arm if this cylinder passes to a three-way valve via a stopcock. The two way valve may open to a vacuum or to a pressure above atmos. This valve is operated automatically by an electronic circuit. according to the level of Hg in the container. The Hg level is monitored by two electrodes one in lower part and one in upper part of Hg.</p> |
