Stress detector
US4716773A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 31, 1985 |
| Grant date | Jan 5, 1988 |
| Priority date | — |
| Expiry date | Dec 31, 2005 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01L3/105
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A stress detector including an AC power source for generating an AC symmetrical wave form voltage, an exciting coil driven by the AC power source for alternatingly magnetizing at least a portion of a ferromagnetic material to be measured in a predetermined direction, a detecting coil for detecting a magnetic flux generated due to the alternating magnetization, and an adder circuit for taking out a part of a voltage applied to the exciting coil, setting an amplitude and a phase of a wave form of the taken-out part of the voltage to preset values, adding the voltage thus obtained to a voltage induced in the detecting coil. The detector gives an output signal representative of a value of stress applied to the material to be measured as a variation either in amplitude or phase depending on the preset phase.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.