US3710700A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electronically controlled shutter
Assignee: Nidec Precision Corp
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Filing: 1971-08-24
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Granted: 1973-01-16
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Expires: 1991-08-24
Abstract
Abstract An electronic shutter for photographic camera comprising a shutter blade opening lever coupled directly to shutter blades which serve concurrently as the diaphragm blades, a shutter blade closing lever arranged to directly hit against one of the shutter blades and concurrently for determining the size of opening of the diaphragm aperture, a contact member for a flash luminescing means provided on the shutter blade opening lever, and diaphragm blades for a light-receiving element and arranged to be controlled of their positions starting always from the fully opened positions toward the minimum diaphragm aperture positions whenever the shutter is released. The aforesaid arrangement of the shutter enables the shutter blades to accomplish quick and precise opening and closing movement in accordance with the proper size of opening of the diaphragm aperture and with the proper exposure time which are both determined, in combination, by an automatic exposure control circuit and also enables that perfect synchronism is established always between the luminescing of the flash bulb and the full opening of the shutter blades.
Inventors
- 👤 C Nakano
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 10:54
CPC Classifications
G; G03; G03B; G03B9/00; G03B9/08; G03B9/10; G03B9/18; G03B7/00; G03B7/08; G03B7/081; G03B7/083; G03B9/22; G03B9/58
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
207 words
A shutter for a photographic camera comprising an automatic exposure control circuit including a bridge circuit having a photoconductive cell in one branch of said bridge, and a delay circuit consisting of said photoconductive cell and a capacitor connected in series with said photoconductive cell; an electromagnet with its time of energization controlled by said automatic exposure control circuit; shutter blades serving and functioning concurrently as diaphragm blades; a shutter blade opening member coupled to said shutter blades and biased in the direction oF opening said shutter blades; a shutter blade closing member movably positioned into the path of movement of said shutter blades and biased in the direction of closing said shutter blades, said shutter blade closing member serving and functioning concurrently as a diaphragm aperture determining member; diaphragm means mounted in the immediate foreground of said photoconductive cell and connected to said shutter blade closing member for altering the light-receiving area of said photoconductive cell; and retard means detechably coupled to said shutter blade closing member for stopping the movement of said shutter blade closing member whenever said electromagnet is energized following the release of the shutter and also for detaching itself from said shutter closing member whenever said electromagnet is de-energized after said energization.
Claim 2
Dependent Claim
207 words
A shutter for a photographic camera comprising an automatic exposure control circuit including a bridge circuit having a photoconductive cell in one branch of said bridge, and a delay circuit consisting of said photoconductive cell and a capacitor connected in series with said photoconductive cell; an electromagnet with its time of energization controlled by said automatic exposure control circuit; shutter blades serving and functioning concurrently as diaphragm blades; a shutter blade opening member coupled to said shutter blades and biased in the direction oF opening said shutter blades; a shutter blade closing member movably positioned into the path of movement of said shutter blades and biased in the direction of closing said shutter blades, said shutter blade closing member serving and functioning concurrently as a diaphragm aperture determining member; diaphragm means mounted in the immediate foreground of said photoconductive cell and connected to said shutter blade closing member for altering the light-receiving area of said photoconductive cell; and retard means detechably coupled to said shutter blade closing member for stopping the movement of said shutter blade closing member whenever said electromagnet is energized following the release of the shutter and also for detaching itself from said shutter closing member whenever said electromagnet is de-energized after said energization.
Claim 3
Dependent Claim
43 words
A shutter for a photographic camera according to claim 1, in which said shutter blades are comprised of two thin plates and said shutter blade closing member is caused to hit against one of said shutter blades whenever said shutter blades are opened.
Claim 4
Dependent Claim
46 words
A shutter for a photographic camera according to claim 1, in which said shutter blade closing member comprises a fixed contact member and a movable contact member which are caused to contact each other by said shutter blade opening member whenever said shutter blades are opened.
Claim 5
Dependent Claim
41 words
A shutter for a photographic camera according to claim 1, in which said diaphragm means is comprised of two thin plates, one of which is caused to move by virtue of the movement of the other whenever the latter is moved.
Claim 6
Dependent Claim
52 words
A shutter for a photographic camera according to claim 1, in which said shutter comprises an interlocking lever engaging both said shutter closing member and said diaphragm means and is operative so that, whenever said shutter is cocked, said diaphragm means is held in the fully opened position by said interlocking lever.
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) | 1976-01-16 | 1976-07-17 | 1977-01-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-01-16 | 1980-07-17 | 1981-01-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-01-16 | 1984-07-17 | 1985-01-16 | $7700.00 | Window Closed / Lapsed |