Device for detecting the presence of photographic film as the film travels along a predetermined path through a film processing apparatus
US3956764A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Nov 1, 1974 |
| Grant date | May 11, 1976 |
| Priority date | — |
| Expiry date | Nov 1, 1994 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03D3/132
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
In the apparatus photographic film is transported along a predetermined path of travel. A flap structure is mounted for pivoting movement about a pivot axis between a rest position in which the flap structure blocks the path of film travel and a work position in which the flap structure does not block the path of film travel. The flap structure is so disposed as to be displaced to and maintained in the work position by film being transported along the path of film travel. The pivot axis of the flap structure is oriented parallel to the surface of the portion of the film which engages the flap structure and transverse to the direction of travel of the portion of the film which engages the flap structure. A detecting arrangement indirectly detects the travel of film along the path of film travel by detecting the pivotal displacement of the flap structure.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.