Patent ID: 8205353

Claim:
Vacuum concentrator comprising a vacuum chamber ( 2 ) with a closure ( 7 ) which may be sealed in an airtight manner, a centrifuge rotor ( 3 ) arranged in the vacuum chamber ( 2 ) with at least one receiver ( 4 ) for at least one vessel ( 5 ) for samples to be dried, a drive motor ( 6 ) arranged outside the vacuum chamber ( 2 ) for driving the centrifuge rotor ( 3 ), a vacuum pump ( 15 ) connected to the vacuum chamber ( 2 ), a tempering device ( 8 ) associated with the vacuum chamber ( 2 ) for tempering the at least one sample in the vacuum chamber ( 2 ), a pressure sensor ( 17 ) associated with the vacuum chamber ( 2 ) for detecting the pressure inside the vacuum chamber ( 2 ) and an electrical control and evaluating device ( 18 ) which is connected to the drive motor ( 6 ), the vacuum pump ( 15 ), the tempering device ( 8 ) and the pressure sensor ( 17 ), for detecting the end point of the vacuum concentration by means of the pressures detected by the pressure sensor ( 17 ) in the vacuum chamber ( 2 ) and terminating the vacuum concentration when the end point is determined, wherein the vacuum pump ( 15 ) has a low delivery rate, which only gradually lowers the pressure in the vacuum chamber until the end point is reached, so that when the end point is reached, as a result of the absence of the release of vaporized sample components, the pressure in the vacuum chamber drops rapidly, and wherein the electrical control and evaluation device detects the reaching of the end point using the rapid pressure drop.