METHODS AND APPARATUS FOR DETERMINING THE PRESENCE OR ABSENCE OF A FLUID LEAK

摘要

Method and apparatus for detecting leaks or defects, including component failure and adverse performance, in a fluid pumping system having a pumping chamber, piston (21), motor (35), inlet, outlet, inlet valve, switchable valve and detector (29). The inlet valve (37) is in fluid communication with the inlet (17) while the switchable valve (41) is in fluid communication with the outlet (19). A pressure measuring device (45) is in fluid communication with the pumping chamber (15) between the inlet valve and switchable valve so as to determine a minimal pressure together with first and second threshold pressures measured at first and second times that correspond to first and second threshold pressure signals. A control means (51) calculates the slope of a line representing the difference of such first and second threshold pressure signals over time so as to compare the slope to a threshold decay value, or to compare the minimal pressure to minimal acceptable values, thus defining pump defects.