Phase shift type linear position detection device
US4556886A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 16, 1982 |
| Grant date | Dec 3, 1985 |
| Priority date | — |
| Expiry date | Feb 16, 2002 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01B7/02
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
About a bobbin, there are wound primary coils in axially displaced locations and wound also is a secondary coil. A core is linearly slidably provided in the bobbin. The primary coils are individually excited by AC signals which are out of phase with each other, e.g. a sine wave signal and a cosine wave signal. The secondary coil thereupon produces an output signal resulting from phase shifting the applied sine or cosine wave signal in accordance with a linear position of the core. Accordingly, the linear position can be detected by measuring phase difference between a reference AC signal and the output signal of the secondary coil. Likewise, velocity and acceleration change may be determined using the position change data.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.