Eddy current proximity sensing means and method useful for determining throttle position
US5247253A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Nov 9, 1990 |
| Grant date | Sep 21, 1993 |
| Priority date | — |
| Expiry date | Nov 9, 2010 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03K17/9525
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
In a preferred embodiment, an inductor excited by a square-wave alternating current to produce a magnetic field in the inductor. A member movable in proximity to the inductor causes losses in the magnetic energy, which losses are directly related to the position of the member with respect to the coil. In another aspect of the invention, there is provided an inductor excited by an alternating current and a moving member which includes a ferromagnetic core having disposed thereon a thin sleeve of high resistivity material. In a further aspect of the invention, there is provided an inductor excited by an alternating current and a moving member, the excitation circuit including an oscillator having a positive temperature coefficient of frequency.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.