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US4303328A Expired / Lapsed US ⏱️ 0.0 years remaining

Device for photographic cameras with focal plane shutter

Assignee: Victor Hasselblad AB
•
Filing: 1980-02-04
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Granted: 1981-12-01
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Expires: 2000-02-04
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Abstract

Abstract The invention relates to an automatic device for protecting the focal plane shutter of a camera when the camera is open. The film magazine of the camera, alternatively the camera back, is sensed by a member disposed in the camera body and directly or preferably indirectly controlling the shutter electronically. When the camera is opened, the sensing member emits a control pulse, which releases the opening part of the shutter. The opening and closing parts of the shutter then are located on both sides of the film gate of the camera where they are protected against damage. When the camera again is closed, the opening part of the shutter again must be cocked. Alternatively, also the closing part of the shutter can be released by a control pulse released when the camera is being closed. The protective device is lockable. (FIG. 2).

Inventors

  • 👤 Kjell-Anders Persson
  • 👤 Lennart Stalfors

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-03 13:40
CPC Classifications
G; G03; G03B; G03B17/00

Claims Analysis

Total Claims: 11
Claim 1
Independent Claim 73 words
A device for photographic cameras with focal plane shutter, characterized in that on the camera surface facing toward the film magazine, alternatively toward the camera back, a member for sensing the film magazine, alternatively the camera back, is provided which directly or indirectly is coupled to the focal plane shutter for releasing the opening part thereof when the film magazine is being removed, alternatively when the camera back is being opened or removed.
Claim 2
Independent Claim 73 words
A device for photographic cameras with focal plane shutter, characterized in that on the camera surface facing toward the film magazine, alternatively toward the camera back, a member for sensing the film magazine, alternatively the camera back, is provided which directly or indirectly is coupled to the focal plane shutter for releasing the opening part thereof when the film magazine is being removed, alternatively when the camera back is being opened or removed.
Claim 3
Dependent Claim 34 words
A device as defined in claim 1, characterized in that the sensing member in lockable in a position or state corresponded by the postion prevailing at attached film magazine, alternatively at closed camera back.
Claim 4
Dependent Claim 23 words
A device as defined in claim 1 or 2, characterized in that the sensing member is designed as an axially movable resilient pin.
Claim 5
Dependent Claim 68 words
A device as defined in claim 1 or 2, characterized in that the sensing member is designed as one fixed and one movable contact portion disposed in the camera body, which movable contact portion can be actuated by a permanent magnet located in the film magazine, alternatively in the camera back, for breaking the contact when the film magazine is attached, alternatively when the camera back is closed.
Claim 6
Dependent Claim 58 words
A device as defined in claim 1 or 2, characterized in that the sensing member is designed as a light source located in the camera body, a mirror disposed in the light path on the film magazine, alternatively on the camera back, and a photocell located in the camera body and reacting on light reflected from the mirror.
Claim 7
Independent Claim 49 words
A device as defined in any one of the claims 1, 2 or 3, characterized in that the pin is lockable in a position inserted and turned through 90° by means of a locking pin extending in a long and narrow groove in the inside of the camera body.
Claim 8
Independent Claim 39 words
A device as defined in any one of the claims 1, 2, or 4, characterized in that the movable contact portion is lockable in broken connection by means of a pin actuated from the outside of the camera body.
Claim 9
Independent Claim 38 words
A device as defined in any one of the claims 1, 2 or 5, characterized in that the sensing member is lockable electronically by means of a signal applied, which simulates the signal emitted by the lightened photocell.
Claim 10
Dependent Claim 40 words
A device as defined in claim 1 or 2, characterized in that it comprises an electric locking means consisting of a switch located on the outside of the camera box for breaking the control circuits of the focal plane shutter.
Claim 11
Dependent Claim 40 words
A device as defined in claim 1 or 2, characterized in that it comprises an electric locking means consisting of a switch located on the outside of the camera box for short-circuiting the releasing solenoids of the focal plane shutter.

References Cited (Backward Citations)

GB440081A Cited
CH255723A Cited
US3491671A Cited
US3724352A Cited
US4017877A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1984-11-30 1985-06-01 1985-12-01 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1988-11-30 1989-06-01 1989-12-01 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1992-11-30 1993-06-01 1993-12-01 $7700.00 Window Closed / Lapsed

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