Patent ID: 9631618
Date: 2017-04-25
CPC Classifications: F04B,G01N

Claim:
1. An arrangement, comprising a piston pump for delivering fluid, the piston pump comprising a piston chamber and a piston arranged such that it can reciprocate in the piston chamber; an additional piston pump in fluid connection with the piston pump, the additional piston pump comprising an additional piston chamber and an additional piston arranged such that it can reciprocate in the additional piston chamber; and a device for determining a leakage of fluid in the piston pump, the device comprising: a control unit for controlling the piston in such a manner that the piston executes two piston chamber evacuation processes with differing evacuation times, in each case for at least partial evacuating of fluid being located in the piston chamber; and a determination unit for determining a leakage of fluid based on a comparison of fluid quantities evacuated from the piston chamber in the two piston chamber evacuation processes, wherein: the additional piston pump is arranged so as to accommodate at least temporarily a proportion of the fluid evacuated during the piston chamber evacuation processes; and the determination unit is set up so as to determine the leakage based on a difference of a volume of fluid lost within different measurement intervals corresponding to the two piston chamber evacuation processes, wherein a residence time of the piston pump in two different pump states is of different length, and wherein the two different pump states comprise a first pump state in which the piston chamber is decoupled from the additional piston chamber and a second pump state in which the piston chamber is coupled to the additional piston chamber.