Abstract: A centrifuge with a rotor set-up having at least one magnetic bearing is invented to operate a novel centrifuge. The rotor arrangement is connected with at least one permanent magnet configuration which is radially separated by small gap from a passive superconducting magnet stator. The permanent magnets which are adjusted in such a way that the escaping magnetic flux penetrates the adjacent surface of the passive superconducting magnet stator at a substantially perpendicular orientation. A driving motor unit, preferably in the form of a contactless induction engine, ensures a free and frictionless rotation. The passive superconducting magnet stator is comprised a melt textured superconducting YBCO material of high critical current density which can be cooled below its critical temperature of T=92 K using an integrated cryogenic unit to obtain the superconducting state. The stator has a preferred shape of a cylinder or hollow cylinder.

Abstract: In order to determine an imbalance of a rotor caused to turn by means of a driving arrangement, imbalance-produced deflections or accelerations of the driving arrangement, spring-loaded with respect to a stationary housing, are determined and relayed as an electrical signal to an evaluation device. The sensor may be, for example, a piezoelectric crystal for detection of accelerations of the drive unit caused by imbalance or a path sensor for detection of deflections of the drive unit relative to the housing as a result of imbalance. The signal is evaluated as a function of the rotary speed of the rotor by means of an adaptive band filter. The method is especially suitable for determination of imbalance during operation of laboratory centrifuges, where an imbalance can occur, for example, from breakage of test tubes.

Abstract: Given is an operating light, with one or several spotlights, each with a light source, that is shielded by a counter reflector in the direction of radiation. The stream of light is focused by the counter reflector and a reflector onto an optical system closing off the housing in the direction of radiation. To guarantee a homogeneous illumination of deeper surgical wounds also, the optical system is structured as a Fresnel lens made up of annular prisms that contain a dioptric central region and a catadioptric edge (rim) region. The slope of the flanks and the height of the annular prisms are dimensioned such that the light beams emanating from the Fresnel lens cut the optical axis at a distance that is all the greater the shorter the distance with which the light beams emanate from the Fresnel lens is away from the optical axis.