US3882520A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Focusing device for camera having selectable focal lengths
Assignee: Eastman Kodak Co
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Filing: 1974-06-10
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Granted: 1975-05-06
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Expires: 1994-06-10
Abstract
Abstract A camera includes a focusable primary lens, a selectively usable converter lens for changing the camera''s effective focal length, and a movable focus member for adjusting the axial position of the primary lens. A cam member with two cam surfaces is movable with the focus member, and a pair of cam followers on the primary lens are arranged so that one of the followers abuts one of the cam surfaces when the converter lens is used and so that the other follower abuts the other cam surface with the converter lens is not used. The cam surfaces have different slopes so that the mechanical gain between the focus member and the primary lens changes when the converter lens is moved into and out of the camera''s optical axis.
Inventors
- 👤 Leonard F Kamp
- 👤 Edward J Koval
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 18:18
CPC Classifications
G; G03; G03B; G03B13/00; G03B13/18; G02; G02B; G02B7/00; G02B7/02; G02B7/04; G03B17/00; G03B17/02; G03B17/12
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
164 words
In a camera having an axially movable primary lens, a converter lens movable into and out of axial alignment with said primary lens, and a movable focus member; the improvement comprising: a cam member operatively connected to said focus member for movement therewith, said cam member having first and second cam surfaces of different slopes; first and second cam followers integral with said primary lens; and spring means for (1) urging said first cam follower into abutment with said first cam surface when said converter lens is out of axial alignment with said primary lens and (2) urging said second cam follower into abutment with said second cam surface when said converter lens is in axial alignment with said primary lens, whereby, when said focus member is moved a given distance, said primary lens will move one distance if the converter lens is axially aligned with the primary lens and different distance if the converter lens is not so aligned with the primary lens.
Claim 2
Dependent Claim
164 words
In a camera having an axially movable primary lens, a converter lens movable into and out of axial alignment with said primary lens, and a movable focus member; the improvement comprising: a cam member operatively connected to said focus member for movement therewith, said cam member having first and second cam surfaces of different slopes; first and second cam followers integral with said primary lens; and spring means for (1) urging said first cam follower into abutment with said first cam surface when said converter lens is out of axial alignment with said primary lens and (2) urging said second cam follower into abutment with said second cam surface when said converter lens is in axial alignment with said primary lens, whereby, when said focus member is moved a given distance, said primary lens will move one distance if the converter lens is axially aligned with the primary lens and different distance if the converter lens is not so aligned with the primary lens.
Claim 3
Dependent Claim
27 words
The improvement as defined in claim 1 wherein said cam member comprises a wedge-shaped projection, said first and second cam surfaces being opposed sides of said projection.
Claim 4
Dependent Claim
54 words
The improvement as defined in claim 2 wherein: said first and second cam followers are spaced apart by a predetermined distance; and said wedge-shaped projection fills said predetermined distance when the camera is focused to infinity, whereupon said first and second cam surfaces are in contact with said first and second cam followers, respectively.
Claim 5
Dependent Claim
23 words
The improvement as defined in claim 1 wherein said spring means includes a single spring interconnecting said converter lens and said primary lens.
Claim 6
Dependent Claim
57 words
The improvement as defined in claim 1 further comprising first and second stops, said fIrst stop defining the limit of travel of said converter lens when moved out of axial alignment with said primary lens and said second stop defining the limit of travel of said converter lens when moved into axial alignment with said primary lens.
Claim 7
Dependent Claim
59 words
The improvement as defined in claim 5 wherein said spring means is arranged to (1) urge said converter lens against said first stop when urging said first cam follower into abutment with said first cam surface and (2) urge said converter lens against said second stop when urging said second cam follower into abutment with said second cam surface.
References Cited (Backward Citations)
US3185061A
Cited
US3588228A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-05-05 | 1978-11-04 | 1979-05-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-05-05 | 1982-11-04 | 1983-05-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-05-05 | 1986-11-04 | 1987-05-06 | $7700.00 | Window Closed / Lapsed |