| 摘要 |
<p>The invention relates to a pump system for providing and maintaining a controlled outflow, comprising a couple of piston pump units (1a, 1b), having at least two cylinders (2a, 2b, 2c, 2d) each with a piston (3a, 3b, 3c, 3d) slidably arranged in each cylinder. It further comprises means for controllably moving the piston in each cylinder, namely by an eccentric wheel (15a, 15b, 15c, 15d) for each of said pistons, acting on one end thereof. There is also provided a control unit for dynamically changing the speed of movement of said means for moving the piston, in response to pressure changes in the system on the pressure side, for maintaining a desired flow out of the pump. The pump system further comprises a valve means (10a, 10b) for proportioning solutions to be mixed according to a predetermined ratio, said valve means being switchable between each source of solutions (A, B, A', B'). Said valve means is controlled by a control unit having integrating means for integrating the flow during suction from a first source of solution to be mixed, and means for switching to another source of solution when the integration corresponds to the predetermined proportion of the solution being sucked.</p> |
