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US3683776A Expired / Lapsed US ⏱️ 0.0 years remaining

Electronic shutter switch means responsive to the movement of a mirror driving member in a single lens reflex camera

Assignee: Nikon Corp
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Filing: 1968-10-28
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Granted: 1972-08-15
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Expires: 1988-10-28
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Abstract

Abstract A timing circuit is employed for the shutter in a reflex camera having a retractable mirror. A switch for energizing the timing circuit is disposed in the path of movement of a driving member which actuates the shutter and is engageable with a driving mechanism for raising the mirror to photo-taking position and retracting the mirror into viewing position. When the driving member is positioned to place the mirror in the viewing position, the switch is open. When the driving member begins movement to place the mirror in the photo-taking position, the driving member acts to close the switch. The timing circuit, including an electromagnet, is energized when the switch is closed in response to the release of the shutter to the open position. The timing circuit maintains the electromagnet in energized condition for a predetermined time, after which the shutter is released.

Inventors

  • 👤 Shigeo Ono

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-31 09:51
CPC Classifications
G; G03; G03B; G03B19/00; G03B19/02; G03B19/12; G03B17/00; G03B17/42; G03B9/00; G03B9/58

Claims Analysis

Total Claims: 6
Claim 1
Independent Claim 267 words
A shutter actuating device for a single lens reflex camera having a shutter successively movable to open and closed positions defining an exposure sequence, a timing circuit including an electromagnet for releasably holding the shutter to control the exposure sequence, the device comprising a reflecting mirror normally biased tOward a viewing position and movable between a viewing position and a photo-taking position, a driving mechanism for raising the mirror to photo-taking position and retracting the mirror to viewing position, the driving mechanism including a driving member engageable with the mirror and movable between a first position in which the driving member disengages from the mirror which is in the viewing position and a second position in which the driving member raises the mirror to the photo-taking position against the biasing force, a switch adapted to actuate the timing circuit disposed in the path of movement of said driving member, said switch being opened by the driving member in the first position and closed when the driving member starts movement toward the second position, means for releasably holding the shutter in closed position including a shutter release member in the path of movement of said driving member, whereby the shutter is opened after the mirror has been raised to photo-taking position, the timing circuit maintaining the electromagnet in an energized condition for a predetermined time, means responsive to the de-energization of the electromagnet for releasing the shutter to end the exposure sequence, and manually operable means for releasably holding said driving mechanism to allow placement of the mirror in a raised position prior to actuation of the shutter.
Claim 2
Dependent Claim 267 words
A shutter actuating device for a single lens reflex camera having a shutter successively movable to open and closed positions defining an exposure sequence, a timing circuit including an electromagnet for releasably holding the shutter to control the exposure sequence, the device comprising a reflecting mirror normally biased tOward a viewing position and movable between a viewing position and a photo-taking position, a driving mechanism for raising the mirror to photo-taking position and retracting the mirror to viewing position, the driving mechanism including a driving member engageable with the mirror and movable between a first position in which the driving member disengages from the mirror which is in the viewing position and a second position in which the driving member raises the mirror to the photo-taking position against the biasing force, a switch adapted to actuate the timing circuit disposed in the path of movement of said driving member, said switch being opened by the driving member in the first position and closed when the driving member starts movement toward the second position, means for releasably holding the shutter in closed position including a shutter release member in the path of movement of said driving member, whereby the shutter is opened after the mirror has been raised to photo-taking position, the timing circuit maintaining the electromagnet in an energized condition for a predetermined time, means responsive to the de-energization of the electromagnet for releasing the shutter to end the exposure sequence, and manually operable means for releasably holding said driving mechanism to allow placement of the mirror in a raised position prior to actuation of the shutter.
Claim 3
Dependent Claim 190 words
A photographic camera comprising a housing having a lens in the front, a focal plane shutter and an intermediate reflecting mirror pivotally mounted within the housing, means for positioning the reflecting mirror in the path of light coming through the lens for viewing an object and for raising the mirror out of the path of light, means for winding the shutter, a timing circuit including an electromagnet, an electric current source for energizing the timing circuit, a switch interposed between the timing circuit and the electric current source, means for retaining the shutter in wound condition and the switch in open state, means for releasing the shutter to the open position, means for releasing the shutter to the closed position, means for closing the switch in response to the release of the shutter independently of the upward movement of the mirror, whereby electric current is applied to the timing circuit and the electromagnet is energized, the timing circuit maintaining the electromagnet in an energized condition for a predetermined time, and means responsive to the de-energization of the electromagnet for actuating the means for releasing the shutter to the closed position.
Claim 4
Dependent Claim 190 words
A photographic camera comprising a housing having a lens in the front, a focal plane shutter and an intermediate reflecting mirror pivotally mounted within the housing, means for positioning the reflecting mirror in the path of light coming through the lens for viewing an object and for raising the mirror out of the path of light, means for winding the shutter, a timing circuit including an electromagnet, an electric current source for energizing the timing circuit, a switch interposed between the timing circuit and the electric current source, means for retaining the shutter in wound condition and the switch in open state, means for releasing the shutter to the open position, means for releasing the shutter to the closed position, means for closing the switch in response to the release of the shutter independently of the upward movement of the mirror, whereby electric current is applied to the timing circuit and the electromagnet is energized, the timing circuit maintaining the electromagnet in an energized condition for a predetermined time, and means responsive to the de-energization of the electromagnet for actuating the means for releasing the shutter to the closed position.
Claim 5
Dependent Claim 273 words
A shutter actuating device for a single lens reflex camera having a shutter successively movable to open and closed positions defining an exposure sequence, a timing circuit including an electromagnet for releasably holding the shutter to control the exposure sequence, the device comprising a reflecting mirror normally biased toward a viewing position and movable between a viewing position and a photo-taking position, a driving mechanism for raising the mirror to photo-taking position and retracting the mirror to viewing position, the driving mechanism including a driving member engageable with the mirror and movable between a first position in which the driving member disengages from the mirror which is in the viewing position and a second position in which the driving member raises the mirror to the photo-taking position against the biasing force, a switch adapted to actuate the timing circuit disposed in the path of movement of said driving member, said switch being opened by the driving member in the first position and closed when the driving member starts movement toward the second position, means for releasably holding the shutter in the closed position including a shutter release member in the path of movement of said driving member, whereby the shutter is opened after the mirror has been raised to photo-taking position, the driving member having three arms, the first arm being related to the mirror for raising and rEtracting the mirror, and the second and third arms being engageable with said switch and shutter release member, respectively, and manually operable means for releasably holding said driving mechanism to allow placement of the mirror in a raised position prior to actuation of the shutter.
Claim 6
Dependent Claim 273 words
A shutter actuating device for a single lens reflex camera having a shutter successively movable to open and closed positions defining an exposure sequence, a timing circuit including an electromagnet for releasably holding the shutter to control the exposure sequence, the device comprising a reflecting mirror normally biased toward a viewing position and movable between a viewing position and a photo-taking position, a driving mechanism for raising the mirror to photo-taking position and retracting the mirror to viewing position, the driving mechanism including a driving member engageable with the mirror and movable between a first position in which the driving member disengages from the mirror which is in the viewing position and a second position in which the driving member raises the mirror to the photo-taking position against the biasing force, a switch adapted to actuate the timing circuit disposed in the path of movement of said driving member, said switch being opened by the driving member in the first position and closed when the driving member starts movement toward the second position, means for releasably holding the shutter in the closed position including a shutter release member in the path of movement of said driving member, whereby the shutter is opened after the mirror has been raised to photo-taking position, the driving member having three arms, the first arm being related to the mirror for raising and rEtracting the mirror, and the second and third arms being engageable with said switch and shutter release member, respectively, and manually operable means for releasably holding said driving mechanism to allow placement of the mirror in a raised position prior to actuation of the shutter.

References Cited (Backward Citations)

US3349678A Cited
US3303766A Cited
US3487759A Cited

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

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