NMR MAS inflow bernoulli bearing
US7170292B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 14, 2005 |
| Grant date | Jan 30, 2007 |
| Priority date | — |
| Expiry date | Oct 14, 2025 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R33/307
- WIPO fieldMeasurement
- WIPO sectorInstruments
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 for…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.