Low supply voltage shutter driver
US5594520A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Feb 21, 1995 |
| Grant date | Jan 14, 1997 |
| Priority date | — |
| Expiry date | Feb 21, 2015 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N23/651
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A mechanical camera shutter requiring voltage in the range of 30 to 60 volts is made to operate from a power supply which provides voltage such lower than is necessary for shutter operation by the inclusion of a capacitor which is charged to 15 volts. The capacitor is operated to add to the insufficient voltage of a power source to provide the requisite high voltage during a critical part of a cycle of operation of the shutter. The shutter driver circuit follows results from the recognition that the shutter requires the high voltage only during the short opening phase of the shutter cycle and is not required during the later holding phase when only a low holding voltage is required. The capacitor is recharged during the holding phase and provides the necessary increased voltage for the next shutter operation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.