Relative-position measuring system of recording-medium library apparatus
US5946160A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 21, 1997 |
| Grant date | Aug 31, 1999 |
| Priority date | — |
| Expiry date | Mar 21, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG05B2219/37487
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A relative-position measuring system of a recording-medium library apparatus including first to third reference flags installed for measuring the magnitude of the gradient of an accessor and a plurality of relative-position flags provided at a cell drum. A flag sensor for detecting the first to third reference flags is installed on a hand mechanism of the accessor for finding the gradients of the accessor with respect to Y and Z axes. The gradients of the accessor with respect to Y and Z axes are used for correcting design tachometer count values of the relative-position flags to give theoretical tachometer count values which are stored in a memory unit. When the accessor is moved, the relative-position flags are sensed by the flag sensor. Actual tachometer count values which are actually obtained when the relative-position flags are detected by the flag sensor are also stored in the memory unit. Then, difference data between the theoretical tachometer count values and the actual tachometer count values is calculated and stored in the memory unit as well.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.