Variable external capacitor for NMR probe
US5768089A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jan 10, 1997 |
| Grant date | Jun 16, 1998 |
| Priority date | — |
| Expiry date | Jan 10, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R33/3628
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A variable external capacitor produces greater functionality for NMR probes by reducing the size of components and efficiently arranging the components. The variable external capacity has a cavity that allows adjustment tools to be extended through the variable external capacitor to adjust additional components that may be stacked above the variable external capacitor. The cavity may be used to house reactance such as a fixed capacitor or inductor connected in parallel with the variable external capacitor. The variable external capacitor includes a polytetrafluoroethylene housing configured to minimize its size and reduce lead lengths of the NMR circuit. A silver deposit plate on the polytetrafluoroethylene housing constitutes a stationary capacitor plate. A drum disposed inside the cavity and movably spaced from the stationary capacitor plate functions as a movable capacitor plate. An anti-rotation rail supports the drum to prevent rotation. The drum includes internal threads that cooperates with threads provided in a plunger for adjustment of the drum in a translational direction. The plunger is supported by the rail and extends outside the cavity of the polytetrafluoroethylene h…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.