Load measurement device
US7493827B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 30, 2005 |
| Grant date | Feb 24, 2009 |
| Priority date | — |
| Expiry date | Nov 6, 2026 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01L5/101
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A variable reluctance load cell for measuring the static or slowly fluctuating load, or tension, on devices is contained in a support tube. A sensor in the tube utilizes opposing C and I shaped magnetic cores attached to opposing ends of the support tube. A magnetic circuit is formed having an inductance defined by the size of the gap between the magnetic cores with the reluctance dominated by the gap. The sensor inductance is coupled with a fixed, predetermined capacitance in a resonant LC circuit, and the resonant frequency is a function of the gap. The sensor is in a cavity within the tube, and the cavity is sealed in a manner that prevents water or other damaging agents from entering the sensor. In this manner, mounting the sensor and tube to a static device and measuring the AC voltage at the sensor, the amount of load, or stress can be determined.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.