Patent ID: 7648627

Claim:
An apparatus for the treatment of a medical liquid, the apparatus comprising: a liquid treatment machine having a compartment configured to contain either one of first and second cassettes, the first cassette having a rigid base body with a first chamber and passages, and a foil that covers the first chamber and passages, the second cassette having a rigid base body with first and second chambers and passages, and a foil that covers the first and second chambers and passages, the first chamber of the first cassette positioned to correspond to the first chamber of the second cassette, and the second chamber of the second cassette positioned to correspond to a region of the first cassette that does not include a chamber, the liquid treatment machine having a machine block and including first and second actuators, the first actuator being aligned with the first chamber of the first cassette when the first cassette is disposed in the compartment of the liquid treatment machine, the first actuator being aligned with the first chamber of the second cassette when the second cassette is disposed in the compartment of the liquid treatment machine, the second actuator being aligned with the region of the first cassette that does not include a chamber when the first cassette is disposed in the compartment of the liquid treatment machine, and the second actuator being aligned with the second chamber of the second cassette when the second cassette is disposed in the compartment of the liquid treatment machine, wherein the liquid treatment machine is adapted so that the first actuator and not the second actuator is operated when the first cassette is disposed in the compartment of the liquid treatment machine and both the first and second actuators are operated when the second cassette is disposed in the compartment of the liquid treatment machine.