Precision optoelectronic rotational position sensor
US4703309A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jul 21, 1986 |
| Grant date | Oct 27, 1987 |
| Priority date | — |
| Expiry date | Jul 21, 2006 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01D5/3473
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An apparatus for determining the rotational position of a shaft comprises opposed first and second disks mounted for relative rotation about a predefined axis, with one of the disks being mounted to the shaft for rotation therewith and the other of the disks being maintained in a reference position. First and second rows of spaced apertures are provided on each disk, which lie in concentric paths of different radial distance from the predefined axis, the first rows being at the same radial distance from the axis and second rows being at the same radial distance from the axis. These apertures are positioned so that apertures of the first rows move into alignment while apertures of the second rows move out of alignment as the disks are rotated relative to each other. A first beam of light of predetermined intensity is oriented so as to intersect the paths of the first rows of apertures, and a second beam of light of predetermined intensity is oriented so as to intersect the paths of the second rows of apertures. First and second photosensors are aligned respectively with the first and second beams of light, and the photosensors are positioned so that the disks are in front of the res…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.