Orthogonal film drive
US4331275A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 14, 1980 |
| Grant date | May 25, 1982 |
| Priority date | — |
| Expiry date | Oct 14, 2000 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03B27/47
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A high precision strip film drive, typically for microfiche film, that includes two spaced-apart drive rollers, separately driven by two servo electric motors. The motors are biased against each other and so maintain a constant tension on the film, while it is stationary or moving. The motors are logic controlled through a pair of rotary encoders. Each encoder is driven by one roller. The outputs of the encoders are combined to give a single servo control signal, devoid of film squew, for accurately spacing the frames upon the microfiche. The encoder electrical outputs are differently handled to provide film velocity information, and still further differently handled to provide direction of motion of the film information. Transverse orthogonal motion of the film is provided by a carriage that supports the rollers, a linear encoder, and a cable system actuated by a third servo motor. The encoder electrical outputs are even further differently handled to accurately finally position the film, as preselected.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.