| 摘要 |
<p>A compliant chamber is formed in a fluid line which connects a fluid supply (12) to a fluid receiver (14). The compliant chamber is alternately in fluid communication with the upstream (16) and downstream segments (18) of the fluid line. When the chamber communicates with the upstream segment (16) it receives and stores fluid at the head pressure. When the segment communicates with the downstream segment (18), a pressure equalization pulse occurs. A pressure sensor (22) in the downstream segment measures the pressure equalization pulse which is proportional to the head pressure. Processing the equalization pulse with the downstream fluid system resistance, the compliance of the compliant chamber and the equilibrium pressure results in a determination of the head pressure. Comparing the head pressure to thresholds permits determination of an occlusion or empty fluid supply. Where a peristaltic pump is used, the chamber is formed between the end fingers of the pump.</p> |
