Supersonic sample spinner
US5508615A · kind A · utility
Inventors
Key dates
| Filing date | Feb 25, 1991 |
| Grant date | Apr 16, 1996 |
| Priority date | — |
| Expiry date | Feb 25, 2011 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R33/307
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Whirl forces in a high-speed hydrostatic air bearing are reduced by orienting the gas supply nozzles so that the pressurized gas enters the bearing opposite to the direction of rotation of the shaft. Stiffness also is thereby increased. Stable operation at supersonic surface speeds may thus be achieved. Diffuser chamfers may be added to the bearing surface to enhance performance at very high pressure ratios. This anti-whirl air bearing is effectively used to support a nuclear magnetic resonance cylindrical sample container capable of high-speed spinning for line-narrowing of solid samples. Motive power required to spin the container at supersonic surface speeds is provided by radial-inflow microturbines with tip diameter less than the bearing diameter and supersonic inlet gas velocities. An axial thrust bearing is included between the microturbine and the sample container. A five-part stator housing construction allows the radio frequency magnetization coil to be supported at minimal spacing from the sample container. The enhanced gas bearings are also beneficial in double rotation NMR experiments.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.