Patent US3695159A successfully refreshed from Google Patents.
US3695159A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Reflex camera with automatic exposure control
Assignee: Pentax Corp
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Filing: 1969-06-09
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Granted: 1972-10-03
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Expires: 1989-06-09
Abstract
Abstract An automatic exposure timing system in a single lens reflex camera with a through the lens light measuring system includes a memory device and a shutter timing network. A first switch alternatively connects the memory device to the light measuring or timing network and a second switch connects a battery to the light measuring system and timing network. A mirror return release member sequentially closes the second switch, actuates the first switch to connect the memory device to the timing network, and releases the mirror. The mirror return sequentially releases the automatic diaphragm and the shutter, and blocks the light measuring photocell. Closing of the shutter returns the switches to their initial condition.
Inventors
- 👤 Kunio Mita
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 08:19
CPC Classifications
G; G03; G03B; G03B7/00; G03B7/08; G03B7/081; G03B7/083
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
152 words
In a camera comprising an objective, a light measuring network including a photocell exposed to light transversing said objective, a computer network for producing an electrical parameter which is a function of the light incident on said photocell, a shutter operating mechanism, a memory device for storing said electrical parameter, shutter timing means responsive to said electrical parameter, switch means for alternatively coupling said memory device to the output of said computing means or to said shutter timing means, means including a retaining member for releasably holding a movable element of said shutter operating mechanism in a shutter cocked position, means driven by said retaining member attendent to the release of said movable element for actuating said switch means to an advanced position coupling said memory device to said shutter timing means, a lagging shutter closing screen and means driven by the closing movement of said screen for retracting said switch means.
Claim 2
Dependent Claim
152 words
In a camera comprising an objective, a light measuring network including a photocell exposed to light transversing said objective, a computer network for producing an electrical parameter which is a function of the light incident on said photocell, a shutter operating mechanism, a memory device for storing said electrical parameter, shutter timing means responsive to said electrical parameter, switch means for alternatively coupling said memory device to the output of said computing means or to said shutter timing means, means including a retaining member for releasably holding a movable element of said shutter operating mechanism in a shutter cocked position, means driven by said retaining member attendent to the release of said movable element for actuating said switch means to an advanced position coupling said memory device to said shutter timing means, a lagging shutter closing screen and means driven by the closing movement of said screen for retracting said switch means.
Claim 3
Dependent Claim
30 words
The camera of claim 1 including a mirror swingable between an advanced viewing position and a retracted photographing position, said retaining member releasably holding said mirror in said advance position.
Claim 4
Dependent Claim
31 words
The camera of claim 1 including an automatic diaphragm movable between an advanced viewing position and a retracted photographing position, said retaining member releasably holding said diaphragm in said advanced position.
Claim 5
Dependent Claim
32 words
The camera of claim 1 wherein said photocell is movable between an advance exposed position and a retracted unexposed position and said retaining member releasably holds said photocell in said advanced position.
Claim 6
Dependent Claim
24 words
The camera of claim 1, including means driven by said shutter driving mechanism for retracting said switch means with the cocking of said shutter.
Claim 7
Dependent Claim
69 words
The camera in accordance with claim 1 comprising means for energizing said network and shutter timing means including a voltage source and a second switch movable between an opened and closed condition and connected in series with said voltage source to said network and shutter timing means and means actuated by said switch means actuating means for closing said second switch prior to said actuation of said switch means.
Claim 8
Dependent Claim
30 words
The camera in accordance with claim 6 wherein said second switch is closed by said actuating means while said switch means couples said light measuring network to said memory device.
Claim 9
Dependent Claim
29 words
The camera of claim 6 including means responsive to the termination of the camera exposure sequence for returning said switch actuating means to a condition opening said second switch.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-10-03 | 1976-04-03 | 1976-10-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-10-03 | 1980-04-03 | 1980-10-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-10-03 | 1984-04-03 | 1984-10-03 | $7700.00 | Window Closed / Lapsed |