Film cassette having friction pad pull strip stress reliever
US4244640A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 10, 1979 |
| Grant date | Jan 13, 1981 |
| Priority date | — |
| Expiry date | Dec 10, 1999 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03B17/265
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An arrangement is provided for reducing the force imparted at the junction between the pull strip and the film strip in a multipurpose film cassette wherein the pull strip is employed to remove a tear tab closure initially sealing a supply of processing fluid. The pull strip is formed with a free end portion adapted to engage a tactile discontinuity in the film strip upon winding of the film strip upon a film spool. The pull strip is provided with a strip of high friction material which, upon continued advancement of the film strip, engages the surface of the outermost convolution of film strip advancing to the reel and which, upon such engagement with the film strip, cooperates with it to resist at least a portion of the force imparted through the pull strip during removal of the tear tab closure, thereby reducing the force imparted to the junction between the pull strip and the film strip.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.