Electricity: measuring and testing – Particle precession resonance – Spectrometer components
Reexamination Certificate
2007-01-30
2007-01-30
Gutierrez, Diego (Department: 2859)
Electricity: measuring and testing
Particle precession resonance
Spectrometer components
Reexamination Certificate
active
11163344
ABSTRACT:
An improved axial gas bearing for a gas-driven NMR MAS sample rotor is disclosed that utilizes inward flow with a low rotational component over a rotor conical end. A conical flow region is formed between the rotor conical end and a conical stator bearing surface such that the included angle defining the stator surface is not less than the included angle defining the rotor conical end. Gas is injected radially inward with a significant axial rearward component from a number of small holes at high velocity from the periphery into the conical flow region. Compared to the radial velocity components, the tangential flow components of the injected gas are small and preferably opposed to the direction of the rotor rotation. The high and accelerating negative radial velocities may result in significant Bernoulli effect, such that the mean axial pressure over the conical rotor end may be less than atmospheric pressure for a given axial clearance, but as the clearance decreases, the hydrostatic effects exceed the Bernoulli effects and the mean axial pressure over the conical rotor end may then exceed atmospheric pressure by a substantial amount. Thus, a self-stabilizing axial bearing is formed with improved stability and stiffness for rotor surface speeds up to at least 80% of the speed of sound. Motive power required to spin the rotor may be provided by a radial-inflow microturbine at the opposite end of the rotor in a way that is readily compatible with automatic sample change.
REFERENCES:
patent: 4201941 (1980-05-01), Fyfe et al.
patent: 4254373 (1981-03-01), Lippmaa et al.
patent: 4275350 (1981-06-01), Hill et al.
patent: 4446430 (1984-05-01), Stejskal
patent: 4456882 (1984-06-01), Doty
patent: 4511841 (1985-04-01), Bartuska et al.
patent: 4739270 (1988-04-01), Daugaard et al.
patent: 4940942 (1990-07-01), Bartuska et al.
patent: 5202633 (1993-04-01), Doty et al.
patent: 5298864 (1994-03-01), Muller et al.
patent: 5508615 (1996-04-01), Doty et al.
patent: 6320384 (2001-11-01), Doty et al.
patent: 6803764 (2004-10-01), Hioka
Beams, J. W. High Rotational Speeds, Journal of Applied Physics, Dec. 1937, pp. 795-806, vol. 8.
Doty et al., Magnetism in High-Resolution NMR Probe Design. II: HR MAS, Concepts in Magnetic Resonance, Jan. 27, 1998, pp. 239-260, vol. 10 (4).
Doty et al., Recent Advances in Solids NMR Probe Technology, Oct. 1, 2005, Publisher: Doty Scientific, Inc.
Doty F. David
Shevgoor Siddarth
Doty Scientific Inc.
Gutierrez Diego
Oppedahl & Olson LLP
Vaughn Megann E
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