| 摘要 |
The pump apparatus (1) comprises a pump body (2) defining a pump chamber (6) and inlet and outlet ducts (15,20) communicating with the pump chamber, a piezoelectric membrane (10) operable to vary the volume of the pump chamber by movement of a flexible wall (9) of the pump chamber and first and second non return valves (13,18) located in the inlet and outlet ducts respectively. Each valve comprises a valve member (22,25) movable into and out of engagement with a cooperating valve seat (21,24) in response to pressure or suction generated in the pump chamber by movement of the wall. Magnets (30,36) are operable to bias the valve members into a seated position. The body including the valves is a disposable item. Priming means (33) acting on the magnets allows the valves to be unseated for flushing and priming the chamber. Sense electrodes (63,64) on the piezoelectric membrane sense occlusion or bubbles when pumping liquids such as drugs during intravenous delivery. |
