Patent US3589043A successfully refreshed from Google Patents.
US3589043A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Portable viewer for microfilm
Assignee: Individual
•
Filing: 1968-11-21
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Granted: 1971-06-29
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Expires: 1988-11-21
Abstract
Abstract A viewer for microfilm specifically adapted for hand operation, wherein a handwheel is rotated to control and actuate the film wind and unwind operations. A gear is fixed to the end of the handwheel axle for movement therewith and engagement with gears provided on the cassette such as to rotate the spools therein in the desired direction to selectively wind and unwind the microfilm on the spools.
Inventors
- 👤 Jeshavahu Klein
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 11:35
CPC Classifications
G; G03; G03B; G03B21/00; G03B21/10; G03B21/11; G03B21/111; G03B35/00; G03B35/18; G03B35/24
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
157 words
A portable film viewer comprising a casing, an optical eyepiece mounted through an exterior wall of said casing, a film cassette removably mounted in said casing contiguous to said optical eyepiece, two film spool supporting bushings mounted in said cassette, a spindle for each bushing journaled in the cassette, coaxial with the bushing, extending therein and protruding outwardly of the cassette, a gear secured to the protruding end of each spindle, a handwheel rotatively mounted on said casing exteriorly thereof, an axle secured to said handwheel and projecting inwardly of said casing, a single driving gear fixed to the free inner end of said axle and located within said casing and adapted to removably mesh with both spindle gears to simultaneously rotate the latter in the same direction, and a unidirectional clutching device between each spindle and associated bushing, whereby rotation of said handwheel will cause selective rotation of said spindles in either one of two directions.
Claim 2
Dependent Claim
157 words
A portable film viewer comprising a casing, an optical eyepiece mounted through an exterior wall of said casing, a film cassette removably mounted in said casing contiguous to said optical eyepiece, two film spool supporting bushings mounted in said cassette, a spindle for each bushing journaled in the cassette, coaxial with the bushing, extending therein and protruding outwardly of the cassette, a gear secured to the protruding end of each spindle, a handwheel rotatively mounted on said casing exteriorly thereof, an axle secured to said handwheel and projecting inwardly of said casing, a single driving gear fixed to the free inner end of said axle and located within said casing and adapted to removably mesh with both spindle gears to simultaneously rotate the latter in the same direction, and a unidirectional clutching device between each spindle and associated bushing, whereby rotation of said handwheel will cause selective rotation of said spindles in either one of two directions.
Claim 3
Dependent Claim
116 words
In a portable film viewer as claimed in claim 1, wherein said clutching device comprises a closely wound coil spring surrounding the associated spindle and located in the associated bushing, one end of the spring being free while the other end is hooked to the associated bushing, at least some of the circumvolutions of said spring being in sliding frictional contact with the associated spindle, whereby rotation of the spindle in one direction causes radially inward coiling of the spring and consequently gripping of the latter on the spindle and rotation of the spindle in the opposite direction tends to produce radIally outward opening of the spring circumvolutions and release of the latter from the spindle.
Claim 4
Dependent Claim
23 words
In a portable film viewer as claimed in claim 2, wherein the two springs are wound in opposite directions towards their free end.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-06-28 | 1974-12-28 | 1975-06-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-06-28 | 1978-12-28 | 1979-06-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-06-28 | 1982-12-28 | 1983-06-29 | $7700.00 | Window Closed / Lapsed |