US3742824A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Automatic exposure device for camera
Assignee: Minolta Co Ltd
•
Filing: 1972-03-10
•
Granted: 1973-07-03
•
Expires: 1992-03-10
Abstract
Abstract An automatic exposure device comprising a striplike electric resistor and a brush in sliding contact therewith which are rotatable by film speed setting operation and diaphragm aperture adjusting operation to be shifted relative to each other so that the electric resistance determined by the change in the relative position of the resistor and brush serves as an element for determining automatic exposure. The device further includes a film speed dial, a positioning disc for setting the dial in a position corresponding to a film speed and an exposure adjusting member which rotates one of the brush or the electric resistor. By disengaging the film speed dial from the positioning disc, the exposure adjusting member is permitted to move the film speed dial in operative relation thereto, while when the positioning disc is in engagement with the film speed dial, the exposure adjusting member can be rotated intentionally.
Inventors
- 👤 H Ueda
- 👤 T Egawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 16:11
CPC Classifications
G; G03; G03B; G03B9/00; G03B9/08; G03B19/00; G03B19/18; G03B7/00; G03B7/003
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
133 words
In an automatic exposure camera, a device for selectively effecting over- and under-exposure comprising: a rotatable means for setting the film speed; a rotatable adjusting member for rotating said rotatable means for setting the film speed; a rotatable film speed dial for indicating the film speed setting; a locking means engageable with said film speed dial for releasably locking said film speed dial in preselected position; and a resilient member mechanically coupling said adjusting member with said film speed dial, said film speed dial being rotatable with said adjusting member through said resilient member when said film speed dial is released from said locking means; and said adjusting member being rotatable in opposition to the resilience of said resilient member when said film speed dial is in lockeD engagement with said locking means.
Claim 2
Dependent Claim
133 words
In an automatic exposure camera, a device for selectively effecting over- and under-exposure comprising: a rotatable means for setting the film speed; a rotatable adjusting member for rotating said rotatable means for setting the film speed; a rotatable film speed dial for indicating the film speed setting; a locking means engageable with said film speed dial for releasably locking said film speed dial in preselected position; and a resilient member mechanically coupling said adjusting member with said film speed dial, said film speed dial being rotatable with said adjusting member through said resilient member when said film speed dial is released from said locking means; and said adjusting member being rotatable in opposition to the resilience of said resilient member when said film speed dial is in lockeD engagement with said locking means.
Claim 3
Dependent Claim
45 words
The automatic exposure device as set forth in claim 1, wherein said rotatable means for setting film speed comprises a variable resistor including a strip resistance element and a rotatable brush in sliding contact therewith, the resistance of said variable resistor electrically setting film speed.
Claim 4
Dependent Claim
73 words
The automatic exposure device as set forth in claim 1, wherein said adjusting member and said film speed dial are concentrically arranged, each having an eccentric post member; and said resilient member includes a spring having opposing legs which sandwich both said post members permitting said adjusting member to rotate in opposite directions against the resilient force of said spring when said film speed dial is in locked engagement with said locking means.
Claim 5
Dependent Claim
76 words
The automatic exposure device as set forth in claim 1, wherein said adjusting member is spatially interposed between said film speed dial and said positioning means, and has formed therein an arcuate window, and including through a pin projecting from said film speed dial through said window into releasable engagement with said locking means, whereby the range of rotation of said adjusting member relative to said dial is limited to the longitudinal dimension of said window.
Claim 6
Dependent Claim
26 words
The automatic exposure device as set forth in claim 1, wherein said resilient member normally urges said film speed dial into engagement with said positioning means.
Claim 7
Dependent Claim
31 words
The automatic exposure device as set forth in claim 1, wherein said film speed dial and said adjusting member are concentrically mounted on the film rewinding knob shaft of the camera.
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) | 1976-07-02 | 1977-01-01 | 1977-07-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-07-02 | 1981-01-01 | 1981-07-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-07-02 | 1985-01-01 | 1985-07-03 | $7700.00 | Window Closed / Lapsed |