US6009281A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Flash device
Assignee: Minolta Co Ltd
•
Filing: 1994-04-04
•
Granted: 1999-12-28
•
Expires: 2014-04-04
Abstract
Abstract A flash device comprising a power source; a main capacitor adapted to be charged by the power source; a flash firing unit operable to consume charge stored in the main capacitor to emit a flash light; a switching unit disposed in a discharge loop for the main capacitor through the flash firing unit; a trigger circuit for exciting the flash firing unit in response to a flash firing command; a pulse output unit, which is operable to output some kinds of pulses, the duty factors of the pulses being different from each other, for inputting a selecting command and For outputting one of the pulses in accordance with the selecting command; and a control unit for causing the switching unit to be switched on and off repeatedly in response to the pulse outputted from the pulse output unit.
Inventors
- 👤 Hiroshi Hosomizu
- 👤 Tsutomu Ichikawa
- 👤 Makoto Kamiya
- 👤 Masatoshi Yoneyama
- 👤 Kenzi Tuzi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 13:50
CPC Classifications
H; H05; H05B; H05B41/00; H05B41/14; H05B41/30; H05B41/32; H05B41/325; G; G03; G03B; G03B15/00; G03B15/02; G03B15/03; G03B15/05; G03B2215/00; G03B2215/05
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
164 words
A flash device comprising: a power source; a main capacitor adapted to be charged by the power source; a flash firing unit operable to consume charge stored in the main capacitor to emit flash light; a voltage doubler for applying to the flash firing unit a voltage of a value approximately twice the voltage of the main capacitor; an insulated gate bipolar transistor disposed in a discharge loop for the main capacitor through the flash firing unit; means for receiving a flash firing command signal; first circuit means for generating a flash exciting signal based on the flash firing command signal; a second circuit means for generating an enabling voltage for the insulated gate bipolar transistor; trigger means for exciting the flash firing unit in response to the flash exciting signal; and control means for applying the enabling voltage to a gate of the insulated gate bipolar transistor and for removing the enabling voltage at the gate in response to a flash terminating command.
Claim 2
Dependent Claim
164 words
A flash device comprising: a power source; a main capacitor adapted to be charged by the power source; a flash firing unit operable to consume charge stored in the main capacitor to emit flash light; a voltage doubler for applying to the flash firing unit a voltage of a value approximately twice the voltage of the main capacitor; an insulated gate bipolar transistor disposed in a discharge loop for the main capacitor through the flash firing unit; means for receiving a flash firing command signal; first circuit means for generating a flash exciting signal based on the flash firing command signal; a second circuit means for generating an enabling voltage for the insulated gate bipolar transistor; trigger means for exciting the flash firing unit in response to the flash exciting signal; and control means for applying the enabling voltage to a gate of the insulated gate bipolar transistor and for removing the enabling voltage at the gate in response to a flash terminating command.
Claim 3
Dependent Claim
35 words
The flash device of claim wherein: said control means applies said enabling voltage to said gate of the insulated gate bipolar transistor independently of the excitation of the flash firing unit by the trigger means.
Claim 4
Dependent Claim
21 words
The device as claimed in claim 1, wherein the flash terminating command disappears subsequent to disappearance of the flash firing command.
Claim 5
Dependent Claim
27 words
The device as claimed in claim 1, wherein said control means includes means for invalidating the flash firing command on the basis of the flash terminating command.
Claim 6
Dependent Claim
41 words
The device as claimed in claim 1, wherein said trigger means includes a semiconductor switching means that is switched on in response to the flash firing command, said flash firing unit being excited when said semiconductor switching means is switched on.
Claim 7
Dependent Claim
29 words
The device as claimed in claim 1, further comprising a constant voltage generating means for applying a predetermined constant voltage to the gate of the insulated gate bipolar transistor.
Claim 8
Dependent Claim
18 words
The device as claimed in claim 6, wherein said predetermined constant voltage is applied from the main capacitor.
References Cited (Backward Citations)
GB1053236A
Cited
US3438766A
Cited
US4006485A
Cited
US4174896A
Cited
US4199242A
Cited
US4275335A
Cited
US4310785A
Cited
US4351594A
Cited
US4422743A
Cited
US4309092A
Cited
JPS5738596A
Cited
JPS5842600A
Cited
US4460264A
Cited
US4427278A
Cited
US4717861A
Cited
US4594614A
Cited
US4592639A
Cited
US4847538A
Cited
JPS6198334A
Cited
GB2166917A
Cited
US4697906A
Cited
JPS62280828A
Cited
JPS6395723A
Cited
JPS6395724A
Cited
JPS6395725A
Cited
JPS6395729A
Cited
JPS6395722A
Cited
JPS6395727A
Cited
JPS6395726A
Cited
JPS6395730A
Cited
JPS6395728A
Cited
US4839686A
Cited
US4951081A
Cited
JPH06150126A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2002-12-27 | 2003-06-28 | 2003-12-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2006-12-27 | 2007-06-28 | 2007-12-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2010-12-27 | 2011-06-28 | 2011-12-28 | $7700.00 | Window Closed / Lapsed |