| 摘要 |
<p>There is provided a positive displacement pump utilizing at least three driven displacer valves and a plurality of driving membranes and at least one pumping membrane to withdraw minute quantities of corrosive fluid from a drum and discharge same from a spray nozzle. The pump is submerged within the fluid to be pumped and is driven by a remotely positioned pneumatic pulse generator comprising pneumatic logic circuitry. The driven displacer valves operate in a particular sequence to draw fluid into the pump body, advance same from pumping chamber to pumping chamber within the pump body, and then discharge same at a constant rate of discrete pulses through an outlet port. The pulse generator and logic circuitry provide the control pulses for operating the displacer valves at the proper times in the operational cycle. The delivery characteristics of the instant pump far exceed the performance capabilities of conventional pumps utilized for similar purposes.</p> |
