US3820145A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Shutter for photographic camera
Assignee: US Philips Corp
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Filing: 1973-05-17
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Granted: 1974-06-25
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Expires: 1993-05-17
Abstract
Abstract This shutter consists of two closely spaced discs, each provided with an aperture and arranged so that the apertures, when they coincide, are located on the optical axis of the objective. These discs are driven by a shaft which is integral with a crank, whose crank pin is attached to a spring. The apertures coincide when during an exposure the discs have their maximum speed of rotation.
Inventors
- 👤 P Gaullier
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 12:12
CPC Classifications
G; G03; G03B; G03B9/00; G03B9/08
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
132 words
A shutter mechanism arranged between two lenses of a photographic camera comprising first and second discs rotatably mounted and closely spaced between said lenses, an aperture in each of said discs arranged so that upon coincidence said apertures are located on the optical axis of the camera objective, means connected to each of said discs for rotating said discs in opposite directions, a shaft connected to said rotating means for driving same, a crank connected to said shaft, a return spring connected to said crank, means for turning said crank so as to tension said return spring when tensioning said shutter, said return spring being in the fully relaxed position when said apertures coincide, and an anti-return device connected to said crank so that said shaft can rotate in only one direction.
Claim 2
Dependent Claim
132 words
A shutter mechanism arranged between two lenses of a photographic camera comprising first and second discs rotatably mounted and closely spaced between said lenses, an aperture in each of said discs arranged so that upon coincidence said apertures are located on the optical axis of the camera objective, means connected to each of said discs for rotating said discs in opposite directions, a shaft connected to said rotating means for driving same, a crank connected to said shaft, a return spring connected to said crank, means for turning said crank so as to tension said return spring when tensioning said shutter, said return spring being in the fully relaxed position when said apertures coincide, and an anti-return device connected to said crank so that said shaft can rotate in only one direction.
Claim 3
Dependent Claim
27 words
The shutter mechanism according to claim 1 wherein one of said discs is cut-away as much as possible to lower the moment of inertia of said shutter.
Claim 4
Dependent Claim
144 words
The shutter mechanism according to claim 1 further including means for varying exposure time comprising a first rod one end of which is attached to said crank, a movable pin attached to the other end of said first rod, one end of said return spring attached to said movable pin the other end thereof attached to a connection point, a second rod being fixed at one end thereof and attached at the other end thereof to said movable pin so as to cause said movable pin to describe a given path, means for adjusting the position of said connection point so as to vary the tensioning force of said return spring comprising a third rod connected at one end thereof to said connection point and at the other end thereof to a pivot point defining an axis about which said connection point is adjustable.
Claim 5
Dependent Claim
97 words
The shutter mechanism according to claim 3 further comprising means for rotating said third rod about said pivot point so that when said first rod is arranged substantially in line with said return spring said spring will exert the largest force on said crank when tensioned so as to cause the shortest exposure time, and so that when said third rod is rotated so that said return spring is arranged substantially perpendicular to said first rod said return spring will exert the smallest force on said crank when tensioned so as to cause the longest exposure time.
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) | 1977-06-24 | 1977-12-24 | 1978-06-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-06-24 | 1981-12-24 | 1982-06-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-06-24 | 1985-12-24 | 1986-06-25 | $7700.00 | Window Closed / Lapsed |