Lens-fitted photo film unit
US5875356A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 19, 1997 |
| Grant date | Feb 23, 1999 |
| Priority date | — |
| Expiry date | Sep 19, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03B19/04
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A lens-fitted photo film unit is pre-loaded with a photo film of a predetermined length. The photo film is retained on a spool. A winder wheel is connected to the spool. After each frame is exposed on the photo film, the winder wheel is manually rotated to wind the photo film into a cassette shell about the spool. In the lens-fitted photo film unit, a combination of a detector cutout and a protruded portion detects that the winder wheel has made a predetermined number of rotations, which depends upon the predetermined length of the photo film. A combination of a recess and a protruded portion locks rotation of the winder wheel in response to rotation of the winder wheel to a predetermined rotational position after the predetermined number of the rotations of the winder wheel. The winder wheel is inhibited from being rotated after the photo film is entirely wound into the cassette shell.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.