Pump
First Claim
1. A pump system for providing and maintaining a stable flow, comprising a first and a second pump unit, each pump unit comprisingi) two cylinders (2a, 2b) with a piston (3a, 3b) slidably arranged in each cylinder;
- ii) moving means (15a, 15b, 15c, 15d, 17, 19) for independently moving the pistons in said cylinders;
iii) stepper motor means (22a, 22b, 22c, 22d) for causing said independent movement of each of said moving means (15a, 15b, 15c, 15d, 17, 19) to cause said movement of the pistons;
iv) a control unit (21, 22) for dynamically changing the speed of movement of said pistons, in response to measurement data indicative of pressure changes in the system on the pressure side.
3 Assignments
0 Petitions
Accused Products
Abstract
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 devices for controllably moving the piston in each cylinder, namely by an eccentric wheel (15a, 15b, 15c, 15d) for each of the pistons, acting on one end thereof. There is also provided a control unit for dynamically changing the speed of movement of the devices 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 switching valves (10a, 10b) for proportioning solutions to be mixed according to a predetermined ratio, the valves being switchable between each source of solutions (A, B, A′, B′) and are controlled by a control unit having integrating method for integrating the flow during suction from a first source of solution to be mixed, and a method for switching to another source of solution when the integration corresponds to the predetermined proportion of the solution being sucked.
41 Citations
12 Claims
-
1. A pump system for providing and maintaining a stable flow, comprising a first and a second pump unit, each pump unit comprising
i) two cylinders (2a, 2b) with a piston (3a, 3b) slidably arranged in each cylinder; -
ii) moving means (15a, 15b, 15c, 15d, 17, 19) for independently moving the pistons in said cylinders;
iii) stepper motor means (22a, 22b, 22c, 22d) for causing said independent movement of each of said moving means (15a, 15b, 15c, 15d, 17, 19) to cause said movement of the pistons;
iv) a control unit (21, 22) for dynamically changing the speed of movement of said pistons, in response to measurement data indicative of pressure changes in the system on the pressure side. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10)
-
-
11. A method of ascertaining a controlled flow out from pump system comprising a piston pump having at least two cylinders each having one independently movable piston arranged therein, and a control unit for controlling the speed of movement of said pistons, comprising
i) running the pistons such that the delivery phases of each said cylinder overlap; -
ii) measuring the pressure on the delivery side of said pump;
iii) feeding a signal representative of said pressure to a control unit, said control unit increasing or decreasing the speed of movement of said pistons in response to said pressure, to compensate for fluctuations in pressure. - View Dependent Claims (12)
-
Specification