| 摘要 |
<p>A device for pumping liquids which are highly sensitive to mechanical strains may be conveniently used in hemodialysis, ultrafiltration, hemofiltration and plasma separation apparatuses in order to provide for blood circulation. The pumping device comprises a rigid casing (103; 203) which has a flexible wall part (102; 202) and a sealed cavity (101; 201) with variable volume. The sealed cavity (101; 201) contains a working medium and is connected by means of a conduit (104; 204) to a pressure generator. The rigid casing (103; 203) has also a liquid-tight circulation chamber for the liquid to be circulated, which chamber is provided with supply and discharge conduits (108, 109; 208, 209) and comprises at least a flexible wall part (106; 206). The flexible walls of the casing (102; 202) and of the circulation chamber (106; 206) are arranged facing each other and their surfaces are susceptible of being brought into contact.</p> |
