| 摘要 |
<p>Hydraulic-exchange pumping device comprising two containers or tanks (1, 2), inside each of which there are defined: a chamber (5, 7) for the product to be pumped, which is respectively connected, through a delivery valve (26, 26') and a suction valve (25, 25'), to the lines of delivery (24) and of intake (23) of the product to be pumped, as well as a chamber (6, 8) for the hydraulic drive fluid, which is connected to a pump (18) through a four-way, three-position distribution box (4). This partitioning is accomplished by means of an internal elastic membrane (27) having a decreasing thickness from the its peripheral edge towards its central zone, which can be also equipped with a strengthening cloth embedded inside it, as well as with a set of metal rings (29-33...) having a cross-section surface area decreasing towards the centre of the same membrane.</p> |
