Method and apparatus for machine absolute positioning measurement
US4580209A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 6, 1984 |
| Grant date | Apr 1, 1986 |
| Priority date | — |
| Expiry date | Feb 6, 2004 |
Classification
- Technology area (CPC —)General
Abstract
A method and apparatus for absolute position measurement for numerically controlled machines is provided. The invention produces a unique measurement signal for all locations within the range of a movable machine member using two measuring devices. Each measuring device produces a unique measurement signal within a portion of the range of motion that cyclically repeats over the entire range of motion. The measuring devices are so arranged that the measurement signal of one completes no more than one more cycle over the range of motion than the measurement signal of the other. The difference between the two measurement signals is unique for all locations and is used to produce an absolute position signal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.