Patent US3747080A successfully refreshed from Google Patents.
US3747080A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Internal surface drum memory
Assignee: Individual
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Filing: 1970-10-27
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Granted: 1973-07-17
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Expires: 1990-10-27
Abstract
Abstract A magnetic drum recording system using the inner surface of a revolving drum to bear the recording medium. Forms shown include a removable tape strip held in place by centrifugal force, a demountable drum rim, and a bonded-on, discontinuous recording surface using the discontinuity for indexing. Two-surface forms are shown, with one surface demountable and the other normally not, with the second surface co-cylindrical with the first, or on a smaller coaxial drum, or on a flange on the first drum. In one embodiment the tape-receiving surface is grooved to protect against distortion of the tape by foreign matter or air trapped between the tapeand the tape and A conical web connects the hub to the drum in one form so as to move the center of mass inward toward the drive, and an air-cushioned ''''flying'''' record/playback head is shown.
Inventors
- 👤 N Taylor
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 13:33
CPC Classifications
G; G11; G11B; G11B15/00; G11B15/60; G11B15/61; G11B27/00; G11B27/10; G11B5/00; G11B5/48; G11B5/54; G11B5/55; G11B5/5591; G11B5/58; G11B5/60; G11B5/74; G11B5/76
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
102 words
A rotatable drum recording system, comprising a supporting chassis, a cylindrical drum mounted on said chassis for rotation about the longitudinal axis of the drum and having an inner cylindrical surface, a magnetic recording medium disposed in a discontinuous nearfull-circle path along said inner cylindrical surface of said drum in intimate contact therewith during rotation of said drum, and a record/playback head disposed adjacent said medium for recording on and playing back from said medium, said record/playback head being responsive to the passage of the discontinuity in said medium thereby to produce a signal for indexing the rotational position of said medium.
Claim 2
Dependent Claim
102 words
A rotatable drum recording system, comprising a supporting chassis, a cylindrical drum mounted on said chassis for rotation about the longitudinal axis of the drum and having an inner cylindrical surface, a magnetic recording medium disposed in a discontinuous nearfull-circle path along said inner cylindrical surface of said drum in intimate contact therewith during rotation of said drum, and a record/playback head disposed adjacent said medium for recording on and playing back from said medium, said record/playback head being responsive to the passage of the discontinuity in said medium thereby to produce a signal for indexing the rotational position of said medium.
Claim 3
Dependent Claim
19 words
A recording system as described in claim 1, and wherein said medium is bonded to said inner cylindrical surface.
Claim 4
Dependent Claim
28 words
A recording system as described in claim 1 and wherein said medium is formed as a strip of magnetic recording material adapted for selective removal from said drum.
Claim 5
Dependent Claim
29 words
A recording system as described in claim 3 and wherein said strip of magnetic recording material is flexible and formed for longitudinally extending to lie substantially in one plane.
Claim 6
Dependent Claim
70 words
A recording system comprising a supporting chassis, a cylindrical drum mounted on said chassis for rotation about the longitudinal axis of the drum and having an inner cylindrical surface, and a strip of magnetic recording tape disposable along said inner cylindrical surface and held in intimate contact therewith by centrifugal force provided by spinning said drum about said axis, said strip being selectively removable from said drum and replaceable therein.
Claim 7
Dependent Claim
70 words
A recording system comprising a supporting chassis, a cylindrical drum mounted on said chassis for rotation about the longitudinal axis of the drum and having an inner cylindrical surface, and a strip of magnetic recording tape disposable along said inner cylindrical surface and held in intimate contact therewith by centrifugal force provided by spinning said drum about said axis, said strip being selectively removable from said drum and replaceable therein.
Claim 8
Dependent Claim
24 words
A recording system as described in claim 5 further comprising a motive means connected to said drum to spin said drum about said axis.
Claim 9
Dependent Claim
37 words
A recording system as described in claim 5, further comprising a second cylindrical magnetic recording surface for less transient data, said second surface being coaxial with and rotating with said strip, said second surface being normally non-removable.
Claim 10
Dependent Claim
29 words
A recording system as described in claim 7 further comprising a second cylindrical drum disposed within said first cylindrical drum and bearing said second cylindrical magnetic recording surface thereon.
Claim 11
Dependent Claim
27 words
A recording system as described in claim 7 and wherein said second magnetic recording surface is carried on a longitudinally extending flange member borne by said drum.
Claim 12
Dependent Claim
34 words
A recording system as described in claim 7 and wherein said second magnetic recording surface is carried on said inner cylindrical surface of said drum at a different longitudinal position therealong than said strip.
Claim 13
Dependent Claim
26 words
A recording system as described in claim 5 further comprising a record/playback head disposed adjacent said medium for recording on and playing back from said medium.
Claim 14
Dependent Claim
37 words
A recording system as described in claim 5 and wherein said inner cylindrical surface is minutely grooved, whereby foreign matter may be caught in said grooves without interfering with the contact of said strip with said drum.
Claim 15
Dependent Claim
61 words
A recording system as described in claim 12 and wherein said inner cylindrical surface is formed with a plurality of grooves, spaced apart by flat land areas of said inner cylindrical surface which serve to support said strip, at least a portion of said grooves communicating with the atmosphere to release air trapped between said strip and said inner cylindrical surface.
References Cited (Backward Citations)
US3213461A
Cited
US3312963A
Cited
US3174152A
Cited
US3180943A
Cited
US3193811A
Cited
US3172114A
Cited
US3245063A
Cited
US3145386A
Cited
US3177495A
Cited
US3465320A
Cited
US3315861A
Cited
US3480934A
Cited
US3609724A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-07-16 | 1977-01-15 | 1977-07-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-07-16 | 1981-01-15 | 1981-07-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-07-16 | 1985-01-15 | 1985-07-17 | $7700.00 | Window Closed / Lapsed |