Film transportation device for camera
US4734732A · kind A · utility
10Cited by
2References
11Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Apr 21, 1987 |
| Grant date | Mar 29, 1988 |
| Priority date | — |
| Expiry date | Apr 21, 2007 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03B17/425
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A film transportation apparatus having an electric motor as the drive source for transporting the film in which for each frame of the film to be advanced, there are provided a speed control period of, while giving a driving power to the motor, controlling its speed, and a braking period that follows. The factor of causing the speed of movement of the film by the motor to vary is examined in respect to the voltage of the electrical power source, the number of exposed frames of the film and others for the purpose of controlling the effective voltage given to the motor in the speed control period.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.