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Wide gap, permanent magnet biased magnetic bearing systemThe unique features and applications of the presented electrical permanent magnetic bearing system essentially result from three facts: (1) the only bearing rotor components are nonlaminated ferromagnetic steel collars or cylinders; (2) all radial and axial forces are transmitted via radial gaps; and (3) large radial bearing gaps can be provided with minimum electric power consumption. The large gaps allow for effective encapsulation and shielding of the rotors at elevated or low temperatures, corrosive or ultra clean atmosphere or vacuum or high pressure environment. Two significant applications are described: (1) a magnetically suspended x ray rotary anode was operated under high vacuum conditions at 100 KV anode potential, 600 C temperature at the rotor collars and speed 18000 rpm with 13 mm radial bearing gap; and (2) an improved Czochralski type crystal growth apparatus using the hot wall method for pulling GaAs single crystals of low dislocation density. Both crystal and crucible are carried and transported by magnetically suspended shafts inside a hermetically sealed housing at 800 C shaft and wall temperature. The radial magnetic bearing gap measures 24 mm.
Document ID
Document Type
Conference Paper
Boden, Karl
(Forschungszentrum Juelich G.m.b.H. Juelich, Germany)
Date Acquired
September 6, 2013
Publication Date
May 1, 1992
Publication Information
Publication: NASA. Langley Research Center, International Symposium on Magnetic Suspension Technology, Part 2
Subject Category
Mechanical Engineering
Distribution Limits
Work of the US Gov. Public Use Permitted.
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