Film cassette with notched film leader
US5257750A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 22, 1992 |
| Grant date | Nov 2, 1993 |
| Priority date | — |
| Expiry date | May 22, 2012 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03B2217/266
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
In a film cassette, a spool is supported for rotation in an unwinding direction inside a cassette shell, a filmstrip is coiled about the spool to form a film roll with an outermost convolution having a leading end, a pair of flanges are coaxially arranged along the spool with respective peripheral annular lips overlapping the outermost convolution adjacent opposite longitudinal edges of the outermost convolution to radially confine the film roll, respective notches are cut in the longitudinal edges at individual locations nearby the leading end which receive sections of the annular lips to allow sections of the longitudinal edges between the notches and the leading end to overlap the annular lips to hold the leading end spaced from a next-inward convolution of the film roll, and a stripper is positioned closer to one of the longitudinal edges than to the other for receipt between the leading end and the next-inward convolution to divert the leading end into a passageway out of the shell when the spool is rotated in the unwinding direction. According to the invention, the notch in the longitudinal edge that is farther from the stripper is sufficiently shallow to cause the section of…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.