| 摘要 |
<p>A cylindrical container (1) has two annular walls (2, 3) one (2) forming the upper face, and the other (3) situated internally. Two circular, flexible valves (4, 5) aremounted on a central support (9) so that they close off the central holes in the annular walls, from beneath. An entry tube (8) connected to the storage vat at the desired liquid level, communicates with the chamber between the valves and a discharge pipe (7) with the chamber (6) below the valves. Any excess pressure in the vat opens the lower valve whereas any suction opens the upper valve. A U-tube (34) between the entry tube and vat will allow the maintenance of a vat pressure above atmospheric, by trapping a certain amount of the liquid.</p> |
