US4737806A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus for flash photographing
Assignee: Ricoh Co Ltd
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Filing: 1987-04-08
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Granted: 1988-04-12
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Expires: 2007-04-08
Abstract
Abstract An apparatus for conducting flash photographing by a camera capable of incorporating or setting therein a flashlight device and generating a trigger signal at full opening of a shutter, and a capacitor adapted to release electric charge stored therein in response to said trigger signal for a flash discharge tube to emit flash.
Inventors
- 👤 Toru Sakaguchi
- 👤 Akira Takahashi
- 👤 Akira Ueno
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 09:30
CPC Classifications
H; H05; H05B; H05B41/00; H05B41/14; H05B41/30; H05B41/32
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
227 words
An apparatus for conducting flash photographing by a camera capable of incorporating or setting therein a flashlight device and generating a trigger signal at full opening of a shutter, and a capacitor adapted to release electric charge stored therein in response to said trigger signal for a flash discharge tube to emit, said apparatus comprising; a DC.DC converter for charging said capacitor by increasing voltage of a power source battery, a first timer adapted to be actuated when charging of said capacitor is started or when charging voltage reaches a predetermined level and set for a time at which charging voltage reaches upper limit voltage below withstand voltage of the flash discharge tube for initial charge, a second timer adapted to be actuated when charging voltage reaches said upper limit voltage and set for a time at which charging voltage reaches lower limit voltage for proper emission according to spontaneous discharge, a third timer adapted to be actuated when charging voltage is below the lower limit voltage and set for a time at which charging voltage reaches a level between the lower limit voltage and withstand voltage, and oscillation regulating means for turning said DC.DC converter off with output of said first timer, turning said DC.DC converter on with output of said second timer, and turning said DC DC converter off with output of said third timer.
Claim 2
Independent Claim
227 words
An apparatus for conducting flash photographing by a camera capable of incorporating or setting therein a flashlight device and generating a trigger signal at full opening of a shutter, and a capacitor adapted to release electric charge stored therein in response to said trigger signal for a flash discharge tube to emit, said apparatus comprising; a DC.DC converter for charging said capacitor by increasing voltage of a power source battery, a first timer adapted to be actuated when charging of said capacitor is started or when charging voltage reaches a predetermined level and set for a time at which charging voltage reaches upper limit voltage below withstand voltage of the flash discharge tube for initial charge, a second timer adapted to be actuated when charging voltage reaches said upper limit voltage and set for a time at which charging voltage reaches lower limit voltage for proper emission according to spontaneous discharge, a third timer adapted to be actuated when charging voltage is below the lower limit voltage and set for a time at which charging voltage reaches a level between the lower limit voltage and withstand voltage, and oscillation regulating means for turning said DC.DC converter off with output of said first timer, turning said DC.DC converter on with output of said second timer, and turning said DC DC converter off with output of said third timer.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-04-12 | 1991-10-12 | 1992-04-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-04-12 | 1995-10-12 | 1996-04-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-04-12 | 1999-10-12 | 2000-04-12 | $7700.00 | Window Closed / Lapsed |