Helmut Zangenfeind
19Patents
8h-index
21Co-inventors
72Inventor score
Filing activity: Jan 26, 1976 → Apr 10, 1998
Most-cited inventions
| Patent | Title | Area | Cited by | Status |
|---|---|---|---|---|
| US4073588A | Apparatus for applying indicia to films and envelopes in photographic processing laboratories | Physics | 17 | Expired |
| US5154410A | Apparatus for straightening and stacking envelopes for photosensitive materials | Performing Operations; Transporting | 15 | Expired |
| US4094726A | Apparatus for processing exposed photographic films and cassettes for such films | Physics | 14 | Expired |
| US5279696A | Apparatus for reading and processing encoded information of uniting bands for webs of photographic material | Emerging Cross-Sectional Technologies | 13 | Expired |
| US4888613A | Method of and apparatus for processing exposed photographic films | Physics | 12 | Expired |
| US4046614A | Splicing apparatus for photographic films or the like | Physics | 11 | Expired |
| US4732278A | Apparatus for transporting cartridge for exposed roll film | Physics | 10 | Expired |
| US4621970A | Apparatus for removing reels with exposed roll films from cartridges | Physics | 8 | Expired |
| US4643371A | Apparatus for unwinding exposed roll films from reels | Physics | 7 | Expired |
| US4894675A | Apparatus for splicing together undeveloped customer films in a darkroom | Physics | 5 | Expired |
| US4004724A | Apparatus for removing exposed films and backing strips from containers | Physics | 3 | Expired |
| US4799076A | Apparatus for affording access to exposed but undeveloped films in a dark chamber | Physics | 3 | Expired |
| US4087033A | Apparatus for opening film cassettes | Emerging Cross-Sectional Technologies | 2 | Expired |
| US5781819A | Device for feeding film cartridges | Physics | 1 | Expired |
| US5708905A | Device for automatic removal of a photographic film from a cartridge | Physics | 1 | Expired |
| US4282997A | Apparatus for removing exposed films and backing strips from cassettes | Physics | 1 | Expired |
| US5842077A | Device for the automatic removal of a photographic film from a cartridge | Physics | 1 | Expired |
| US4360138A | Apparatus for removing exposed films and backing strips from cassettes | Physics | 0 | Expired |
| US6000861A | Method of and device for testing a photographic film | Physics | 0 | Expired |
Source: USPTO / EPO open patent data. Inventor disambiguation is heuristic; counts are objective bibliographic measures.