US3738240A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Lens attachment for flash-light photographing
Assignee: Canon Inc
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Filing: 1971-09-28
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Granted: 1973-06-12
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Expires: 1991-09-28
Abstract
Abstract In an automatic flash camera having a lens with a rotatable focusing ring, a lens attachment coacts with the focusing ring to control the camera. In the attachment, a mounting arrangement detachably mounts the attachment to the end of the lens. An interconnecting arrangement, rotatably mounted on the mounting arrangement, engages the focusing ring to move therewith. A variable resistance system is mounted on the two arrangements and is varied by movement of the interconnecting arrangement relative to the mounting arrangement. The variable resistance system includes an adjustable member which is movable between a number of positions. In one position the variable resistance system exhibits one range of resistances corresponding to one type of lens when the interconnecting arrangement is moved. In other positions the variable resistance system exhibits other ranges of resistances each corresponding to lenses of other aperture ratios and focal lengths. An electrical system connected to the variable resistance system responds to the value of the resistance exhibited and controls the diaphragm of the camera for automatic flashlight photography.
Inventors
- 👤 T Mitani
- 👤 T Shirashaki
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 05:12
CPC Classifications
G; G03; G03B; G03B9/00; G03B9/70; G03B7/00; G03B7/16
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
232 words
For an automatic flash camera having an automatic diaphragm control and a photographic lens with a rotatable focusing ring, a lens attachment, comprising mounting means for detachably mounting the attachment at the end of the lens, interconnecting means rotatably mounted on said mounting means and engageable with the focusing ring, variable resistance means mounted on said mounting means and said interconnecting means, said resistance means being variable by movement of said interconnecting means with the focusing ring and having an adjustable member which is movable between a plurality of positions, said variable resistance means exhibiting one range of resistances corresponding to one type of lens when the member is in one position and the interconnecting means is moved relative to the mounting means through a given path, said variable resistance means exhiBiting another range of resistances corresponding to another type of lens when the member is in another position and the interconnecting means is moved relative to the mounting means through a path corresponding to the one path, electrical means connected with said variable resistance means and coupled to said diaphragm control means for adjusting the diaphragm on the basis of an electrical resistance value based upon the rotation of the focusing ring and the position of said member, said member being adjustable to a position causing said resistance means to exhibit a range of values corresponding to the type of lens.
Claim 2
Dependent Claim
232 words
For an automatic flash camera having an automatic diaphragm control and a photographic lens with a rotatable focusing ring, a lens attachment, comprising mounting means for detachably mounting the attachment at the end of the lens, interconnecting means rotatably mounted on said mounting means and engageable with the focusing ring, variable resistance means mounted on said mounting means and said interconnecting means, said resistance means being variable by movement of said interconnecting means with the focusing ring and having an adjustable member which is movable between a plurality of positions, said variable resistance means exhibiting one range of resistances corresponding to one type of lens when the member is in one position and the interconnecting means is moved relative to the mounting means through a given path, said variable resistance means exhiBiting another range of resistances corresponding to another type of lens when the member is in another position and the interconnecting means is moved relative to the mounting means through a path corresponding to the one path, electrical means connected with said variable resistance means and coupled to said diaphragm control means for adjusting the diaphragm on the basis of an electrical resistance value based upon the rotation of the focusing ring and the position of said member, said member being adjustable to a position causing said resistance means to exhibit a range of values corresponding to the type of lens.
Claim 3
Dependent Claim
116 words
An attachment as in claim 1, wherein said variable resistance means includes a plurality of conductive contact means extending along a plurality of separate paths and mounted on one of said interconnecting means and said mounting means, said resistance means further including a slider mounted on the other of said mounting means and said interconnecting means and contacting one of said contact means on the basis of the position of said member and movable along one of the paths when said interconnecting means moves with respect to said mounting means and varying the resistance exhibited by said resistance means on the basis of the type of lens being used and the position of the focusing ring.
Claim 4
Dependent Claim
16 words
An attachment as in claim 1, wherein said variable resistance means extends along a circular path.
Claim 5
Dependent Claim
14 words
A system as in claim 2, wherein said resistor means extend along circular paths.
Claim 6
Dependent Claim
84 words
An attachment as in claim 2, wherein each of said contact means comprises an insulating base plate, a plurality of contact strips extending along the path, said strips being separated from each other, a plurality of resistances connected between said contact strips, the location of said contact strips causing said slider to be connected to different ones of said resistances depending upon the position of said member and the focusing of said ring, and wiring means connecting said resistance means to said circuit means.
Claim 7
Dependent Claim
212 words
A camera, comprising a camera body, an interchangeable lens, an adjustable focusing ring on the lens, mounting means for detachably mounting the attachment at the end of the lens, interconnecting means rotatably mounted on said mounting means and engageable with the focusing ring, variable resistance means mounted on said mounting means and said interconnecting means, said resistance means being variable by movement of said interconnecting means with the focusing ring and having an adjustable member which is movable between a plurality of positions, said variable resistance means exhibiting one range of resistances corresponding to one type of lens with the members in one position and the interconnecting means is moved relative to the mounting means, said variable resistance means exhibiting another range of resistances corresponding to another type of lens when the member is in another position and the interconnecting means is moved relative to the mounting means, electrical means connected with said variable resistance means and coupled to said diaphragm control means for adjusting the diaphragm on the basis of an electrical resistance value based upon the rotation of the focusing ring and the position of said member, said member being adjustable to a position cause said resistance means to exhibit a range of values corresponding to the type of lens.
Claim 8
Dependent Claim
212 words
A camera, comprising a camera body, an interchangeable lens, an adjustable focusing ring on the lens, mounting means for detachably mounting the attachment at the end of the lens, interconnecting means rotatably mounted on said mounting means and engageable with the focusing ring, variable resistance means mounted on said mounting means and said interconnecting means, said resistance means being variable by movement of said interconnecting means with the focusing ring and having an adjustable member which is movable between a plurality of positions, said variable resistance means exhibiting one range of resistances corresponding to one type of lens with the members in one position and the interconnecting means is moved relative to the mounting means, said variable resistance means exhibiting another range of resistances corresponding to another type of lens when the member is in another position and the interconnecting means is moved relative to the mounting means, electrical means connected with said variable resistance means and coupled to said diaphragm control means for adjusting the diaphragm on the basis of an electrical resistance value based upon the rotation of the focusing ring and the position of said member, said member being adjustable to a position cause said resistance means to exhibit a range of values corresponding to the type of lens.
Claim 9
Dependent Claim
118 words
A camera as in claim 6, wherein said variable resistance means includes a plurality of conductive contact means extending along a plurality of separate paths and mounted on one of said interconnecting means and said mounting means, said resistance means further including a slider mounted on the other of said mounting means and said interconnecting means and contacting one of said contact means on the basis of the position of said member and movable along one of the paths when said interconnecting means moves with respect to said mounting means so as to vary the resistance exhibited by said resistance Means on the basis of the type of lens being used and the position of the focusing ring.
Claim 10
Dependent Claim
16 words
A camera as in claim 6 wherein said variable resistance means extends along a circular path.
Claim 11
Dependent Claim
14 words
A system as in claim 7, wherein said resistor means extend along circular paths.
Claim 12
Dependent Claim
84 words
A camera as in claim 7, wherein each of said resistor means comprises an insulating base plate, a plurality of contact strips extending along the path, said strips being separated from each other, a plurality of resistances connected between said contact strips, the location of said contact strips causing said slider to be connected to different ones of said resistances depending upon the position of said member and the focusing of said ring, and wiring means connecting said resistance means to said electrical means.
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) | 1976-06-11 | 1976-12-11 | 1977-06-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-06-11 | 1980-12-11 | 1981-06-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-06-11 | 1984-12-11 | 1985-06-12 | $7700.00 | Window Closed / Lapsed |