US3683768A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Flash photography changeover device
Assignee: Hattori Tokeiten KK
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Filing: 1969-02-25
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Granted: 1972-08-15
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Expires: 1989-02-25
Abstract
Abstract Apparatus in a camera for sensing the brightness of a subject to be photographed and devices for giving a visual indication to the camera operator whether or not a flash unit utilized with the camera is in an operative condition. In addition, apparatus is provided for automatically taking a picture of the subject using the ambient light if there is sufficient ambient light and for energizing the flash unit if there is insufficient ambient light. The apparatus also automatically takes a picture of the subject using ambient light if the flash unit is deflective.
Inventors
- 👤 Kiyoshi Kitai
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 11:22
CPC Classifications
G; G03; G03B; G03B9/00; G03B9/70
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
223 words
A photographic shutter control system for controlling a camera shutter mechanism comprising: a shutter mechanism movable from a closed position to an open position and back to said closed position within a variable set time period defining an exposure time period; a movable trigger lever; actuating means operative in response to movement of said trigger lever in a given direction to effect opening movement of said shutter mechanism to said open position; electromagnetic means energized in response to movement of said trigger lever in said given direction and operative when deenergized to effect return movement of said shutter mechanism to said closed position; flash circuit means including a flash bulb operative in response to opening movement of said actuating means to fire said flash bulb and deenergize said electromagnetic means whereby said shutter mechanism is returned to said closed position; timing circuit means operable independently of said flash circuit means and in response to opening movement of said shutter mechanism for providing a timing signal representative of a predetermined exposure time period; and electric circuit means receptive of said timing signal whenever said flash circuit means is ineffective to fire said flash bulb to maintain said shutter mechanism in said open position for said predetermined exposure time period and deenergize said electromagnetic means whereby said shutter mechanism is returned to said closed position.
Claim 2
Dependent Claim
223 words
A photographic shutter control system for controlling a camera shutter mechanism comprising: a shutter mechanism movable from a closed position to an open position and back to said closed position within a variable set time period defining an exposure time period; a movable trigger lever; actuating means operative in response to movement of said trigger lever in a given direction to effect opening movement of said shutter mechanism to said open position; electromagnetic means energized in response to movement of said trigger lever in said given direction and operative when deenergized to effect return movement of said shutter mechanism to said closed position; flash circuit means including a flash bulb operative in response to opening movement of said actuating means to fire said flash bulb and deenergize said electromagnetic means whereby said shutter mechanism is returned to said closed position; timing circuit means operable independently of said flash circuit means and in response to opening movement of said shutter mechanism for providing a timing signal representative of a predetermined exposure time period; and electric circuit means receptive of said timing signal whenever said flash circuit means is ineffective to fire said flash bulb to maintain said shutter mechanism in said open position for said predetermined exposure time period and deenergize said electromagnetic means whereby said shutter mechanism is returned to said closed position.
Claim 3
Dependent Claim
36 words
A control system according to claim 1; wherein said timing circuit means includes a photosensitive element whose electrical resistance varies in accordance with the intensity of light incident thereon effective to provide a corresponding timing signal
Claim 4
Dependent Claim
26 words
A control system according to claim 1; including indicating means for providing an indication that said flashing circuit means is effective to fire said flash bulb.
Claim 5
Dependent Claim
31 words
A control system according to claim 1; wherein said electric circuit means includes a transistor receptive of and rendered conductive by said timing signal to effect deenergization of said electromagnetic means.
Claim 6
Dependent Claim
69 words
A control system according to claim 1; wherein said flash circuit means comprises means connectable during use of the control system to an electrical energy source having sufficient potential to fire said flash bulb, and conductor means electrically connecting said electromagnetic means to said flash bulb to apply the voltage drop occurring across said energy source when said flash bulb is fired to said electromagnetic means to deenergize same.
Claim 7
Dependent Claim
226 words
A photographic shutter control system for controlling a shutter comprising: trigger means movable in a given direction for releasing the shutter and initiating an exposure; exposure terminating means for effecting termination of the exposure and including a movable member mounted to follow the movement of said trigger means before the release of the shutter; and electric circuit means comprising an electromagnet operative when energized to terminate the following movement of said movable member, brightness delay means for controlling the exposure time in dependence upon the brightness of an object to be photographed during a daylight exposure mode of operation, a flash circuit connectable to a flash device for firing same and including means for connecting said electric circuit means to an electrical power source in response to movement of said trigger means in said given direction to effect energization of said electromagnet and stoppage of the following movement of said movable member in one position defining a flash exposure mode, and a by-pass circuit connected in parallel with said flash circuit and operative in response to movement of said trigger means in said given direction whenever said flash circuit is disabled to connect said electric circuit means to an electrical power source to effect energization of said electromagnet and stoppage of the following movement of said movable member in another position defining a daylight exposure mode.
Claim 8
Dependent Claim
226 words
A photographic shutter control system for controlling a shutter comprising: trigger means movable in a given direction for releasing the shutter and initiating an exposure; exposure terminating means for effecting termination of the exposure and including a movable member mounted to follow the movement of said trigger means before the release of the shutter; and electric circuit means comprising an electromagnet operative when energized to terminate the following movement of said movable member, brightness delay means for controlling the exposure time in dependence upon the brightness of an object to be photographed during a daylight exposure mode of operation, a flash circuit connectable to a flash device for firing same and including means for connecting said electric circuit means to an electrical power source in response to movement of said trigger means in said given direction to effect energization of said electromagnet and stoppage of the following movement of said movable member in one position defining a flash exposure mode, and a by-pass circuit connected in parallel with said flash circuit and operative in response to movement of said trigger means in said given direction whenever said flash circuit is disabled to connect said electric circuit means to an electrical power source to effect energization of said electromagnet and stoppage of the following movement of said movable member in another position defining a daylight exposure mode.
Claim 9
Dependent Claim
33 words
A system according to claim 6 wherein said movable member comprises a resiliently biased toothed cam cooperative with an abutment member, and means movably mounting said cam for movement controlled by said electromagnet.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-08-15 | 1976-02-14 | 1976-08-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-08-15 | 1980-02-14 | 1980-08-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-08-15 | 1984-02-14 | 1984-08-15 | $7700.00 | Window Closed / Lapsed |