Torque sensor
US5146790A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 4, 1990 |
| Grant date | Sep 15, 1992 |
| Priority date | — |
| Expiry date | Jun 4, 2010 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01L3/105
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Torque in a shaft is measured by a torque sensor comprising at least one strain gage. The strain gage has a magnetic circuit comprising a magnetostrictive, soft ferromagnetic element. A drive mechanism applies a first and a second magnetomotive force to the magnetic circuit. The second magnetomotive force has a sense opposite that of the first magnetomotive force. A sensing mechanism senses the state of magnetization of the ferromagnetic element and a detecting mechanism determines the magnitude of that magnetic field applied to the ferromagnetic element by the second magnetomotive force which reduces the magnetization of the element to zero. Torque is derived from the strain indicated by a change in the coercive field of the ferromagnetic element.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.