Rotation speed detection device having a rotation angle detector of inductive type
US4612503A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 14, 1981 |
| Grant date | Sep 16, 1986 |
| Priority date | — |
| Expiry date | Oct 14, 2001 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01D2205/776
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A detection head unit comprises a stator and a rotor. The stator has four poles disposed circumferentially at an interval of 90.degree.. The poles have primary coils and secondary coils wound thereon. Two radially opposing poles constitute a pole pair. The primary coils wound on the poles constituting the pole pair are connected in series and in opposite phase with each other and one pole pair is excited by a sine wave signal and the other pole pair by a cosine wave signal. The rotor is of such a configuration, e.g. an eccentric rotor, as to change reluctance of the respective stator poles in accordance with a rotation angle and change reluctance in a differential manner between the two poles constituting the pole pair. An output signal resulting by phase shifting the sine wave signal applied to the primary coil in accordance with a rotation angle of the rotor is provided by a secondary coil. The rotation angle is detected by measuring phase difference between the reference signal and the output signal of the secondary coil. The rotation speed can be detected by detecting difference in frequency or period between the reference signal and the output signal. Further, acceleration in …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.