Film-thrusting cassette
US5040739A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 12, 1990 |
| Grant date | Aug 20, 1991 |
| Priority date | — |
| Expiry date | Jan 12, 2010 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03B2217/266
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A film cassette comprises a spool rotatable in an unwinding direction to thrust a leader section of a film roll coiled about the spool out of the cassette and in a winding direction to rewind the leader into the cassette; a pair of flanges coaxially arranged along the spool to normally permit each of the flanges to be independently rotated relative to the spool in the unwinding and winding directions and to radially confine the film roll within skirted peripheries of the flanges; and a film stripper received between the leader and the next-inward convolution of the film roll to free the leader from the flanges by inducing the leader to flex the flanges slightly away from one another at their skirted peripheries responsive to rotation of the spool in the unwinding direction. According to the invention, at least one of the flanges can be fixed to the spool to make the fixed flange rotate in unity with the spool when the spool is rotated in the unwinding direction, to improve the ability of the spool to thrust the leader from the cassette. Conversely, the fixed flange can be released from the spool to permit it to be independently rotated relative to the spool when the spool is rotate…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.