| 摘要 |
<p>A method and apparatus for controlling the discharge time of a fluid activated diaphragm pump (10). The control system (100) regulates the discharge time, by measuring the discharge time and comparing the measured time with a predetermined desired discharge time. The control system (100) includes, inter alia, a programmable logic controller (120), an upper and lower proximity switch (154, 156), a target (152), a rod (35) to hold the target (152), a pilot controlled pressure regulator (130), a set of digitally controlled solenoids (135) which control a pilot valve (140), a solenoid (115), and a pressure switch (145). The rod (35) is secured to the diaphragm (30) of the diaphragm pump (10), and the proximity switches (154, 156) respond to the movement of the rod (35) to detect the movement, or stroke, of the diaphragm (30). The pressure supplied to the diaphragm pump (10) is automatically, and continuously, adjusted to maintain a desired discharge time. <IMAGE></p> |
