US3699269A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Double transfer tape copy system
Assignee: Individual
•
Filing: 1971-09-30
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Granted: 1972-10-17
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Expires: 1991-09-30
Abstract
Abstract The disclosure illustrates a method and apparatus for thermomagnetically and magnetically transferring short and long wavelength signals from a master magnetic tape to a pair of magnetizable layers of an intermediate carrier. The signal on the intermediate carrier subsequently is transferred to a copy tape either magnetically or thermomagnetically.
Inventors
- 👤 Philip Smaller
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 23:03
CPC Classifications
G; G03; G03G; G03G19/00; G11; G11B; G11B5/00; G11B5/86; G11B5/865; G11B2005/0002; G11B2005/0005; G11B2005/0021
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
176 words
Apparatus for the transfer of magnetic recordings on a master magnetic storage medium onto a copy magnetic storage medium, said apparatus comprising: an intermediate storage carrier comprising a first layer having a relatively low Curie point not higher than that of the master storage medium and having a coercivity above the coercivity of the copy storage medium and a second layer having a Curie point sufficiently high that it will remain in a ferromagnetic state while the first layer is in the paramagnetic state; means for positioning the intermediate carrier in contact with said master storage medium while the first layer is in a paramagnetic state and maintaining that contact while the first layer reverts to a ferromagnetic state; means for providing a magnetic bias for the second layer of said intermediate carrier while in contact with said master storage medium, the magnetizing force of said magnetic bias being insufficient to erase the magnetic recordings on said master storage medium; means for Copying the magnetic recordings on said intermediate storage carrier onto said copy storage medium.
Claim 2
Dependent Claim
176 words
Apparatus for the transfer of magnetic recordings on a master magnetic storage medium onto a copy magnetic storage medium, said apparatus comprising: an intermediate storage carrier comprising a first layer having a relatively low Curie point not higher than that of the master storage medium and having a coercivity above the coercivity of the copy storage medium and a second layer having a Curie point sufficiently high that it will remain in a ferromagnetic state while the first layer is in the paramagnetic state; means for positioning the intermediate carrier in contact with said master storage medium while the first layer is in a paramagnetic state and maintaining that contact while the first layer reverts to a ferromagnetic state; means for providing a magnetic bias for the second layer of said intermediate carrier while in contact with said master storage medium, the magnetizing force of said magnetic bias being insufficient to erase the magnetic recordings on said master storage medium; means for Copying the magnetic recordings on said intermediate storage carrier onto said copy storage medium.
Claim 3
Dependent Claim
47 words
Apparatus as in claim 1 wherein said copying means comprises: means for placing the intermediate carrier into contact with said copy storage medium subsequent to contact with said master storage medium; and means for magnetically biasing the copy storage medium while in contact with the intermediate carrier.
Claim 4
Dependent Claim
50 words
Apparatus as in cliam 1 wherein: said first layer contacts said master storage medium; said second layer is spaced from said first layer to attenuate the bias field acting on said master storage medium and decrease distortion components while said intermediate carrier is in contact with said master storage medium.
Claim 5
Dependent Claim
50 words
Apparatus as in cliam 1 wherein: said first layer contacts said master storage medium; said second layer is spaced from said first layer to attenuate the bias field acting on said master storage medium and decrease distortion components while said intermediate carrier is in contact with said master storage medium.
Claim 6
Dependent Claim
26 words
Apparatus as in claim 1 further comprising means for heating said first layer prior to contact of said intermediate storage carrier with said master storage medium.
Claim 7
Dependent Claim
32 words
Apparatus as in claim 4 wherein said first layer is relatively thin whereby it heats to the paramagnetic state and cools to the ferromagnetic state in a relatively short period of time.
Claim 8
Dependent Claim
23 words
Apparatus as in claim 1 wherein said first layer is comprised of chromium dioxide and said second layer is comprised of ferrite material.
Claim 9
Dependent Claim
64 words
Apparatus as in claim 2 wherein: said intermdiate storage carrier includes a drum of nonferrous material having said first layer on the outside and said second layer on the inside; means for providing the magnetic bias for the second layer of material; and said apparatus further comprises means for heating said first layer to a paramagnetic state positioned on the outside of said drum.
Claim 10
Dependent Claim
106 words
Apparatus as in claim 1 wherein said master storage medium has a higher coercivity than said copy medium and wherein said means for copying the recordings onto said copy storage medium comprises: means for placing the first layer of said intermediate carrier in contact with said copy storage medium while said copy storage medium is in a paramagnetic state and maintaining that contact while the copy storage medium reverts to a ferromagnetic state, said first layer and said copy storage medium having predetermined Curie points permitting said copy medium to be in a paramagnetic state while said first and second layers remain in a ferromagnetic state.
Claim 11
Dependent Claim
121 words
Apparatus as in claim 1 wherein said master storage medium has a higher coercivity than said second layer medium and wherein: said second layer of said intermediate carrier is placed in contact with said master storage medium and magnetically biased; said means for copying the recordings onto said copy storage medium comprises: means for placing the second layer of said intermediate carrier in contact with said copy storage medium while said copy storage medium is in a paramagnetic state and maintaining that contact while the copy storage medium reverts to a ferromagnetic state, said copy storage medium having a predetermined Curie point permitting said copy to be in a paramagnetic state while first and second layers remain in a ferromagnetic state.
Claim 12
Dependent Claim
31 words
Apparatus as in claim 9 further comprising means for heating the first layer of said intermediate carrier to a temperature level during which the first layer is in its paramagnetic state.
Claim 13
Dependent Claim
38 words
Apparatus as in claim 1 wherein said intermediate carrier comprises an endless flexible belt of nonmagnetic material, said first layer being on the inside of said belt and the second layer being on the outside of said belt.
Claim 14
Independent Claim
164 words
A method for transferring magnetic recordings from a master magnetic storage medium to a copy magnetic storage medium, said method comprising the steps of: placing an intermediate storage carrier having first and second magnetizable layers into slippage-free contact with the master storage medium while the first layer of said intermediate storage carrier is in a paramagnetic state and the second layer remains in a ferromagnetic state and maintaining that contact while the first layer reverts to a ferromagnetic state; magnetically biasing the second of said layers while said intermediate storage carrier is in contact with said master magnetic storage medium, the magnetizing force of said magnetic bias being insufficient to erase the magnetic recordings on said master storage medium; separating the intermediate storage carrier from the master magnetic storage medium after the first layer of the intermediate storage carrier has reverted from the paramagnetic to the ferromagnetic state; and subsequently copying the magnetic recordings on said intermediate storage carrier onto said copy storage medium.
Claim 15
Independent Claim
164 words
A method for transferring magnetic recordings from a master magnetic storage medium to a copy magnetic storage medium, said method comprising the steps of: placing an intermediate storage carrier having first and second magnetizable layers into slippage-free contact with the master storage medium while the first layer of said intermediate storage carrier is in a paramagnetic state and the second layer remains in a ferromagnetic state and maintaining that contact while the first layer reverts to a ferromagnetic state; magnetically biasing the second of said layers while said intermediate storage carrier is in contact with said master magnetic storage medium, the magnetizing force of said magnetic bias being insufficient to erase the magnetic recordings on said master storage medium; separating the intermediate storage carrier from the master magnetic storage medium after the first layer of the intermediate storage carrier has reverted from the paramagnetic to the ferromagnetic state; and subsequently copying the magnetic recordings on said intermediate storage carrier onto said copy storage medium.
Claim 16
Dependent Claim
67 words
A method as in claim 12 wherein said copying of the magnetic recordings on said intermediate storage carrier onto said copy storage medium comprises the steps of: placing the intermediate carrier in contact with the copy magnetic storage medium and magnetically biasing the copy storage medium when in contact with the intermediate storage carrier; and subsequently separating the intermediate storage carrier from the copy magnetic storage medium.
Claim 17
Dependent Claim
96 words
A method as in claim 12 wherein the copying of the magnetic recordings on the intermediate storage carrier onto said copy storage medium comprises the steps of: placing the second layer of said intermediate carrier in contact with said copy storage medium while said copy storage medium is in a paramagnetic state and maintaining that contact while the copy storage medium reverts to a ferromagnetic state, said copy storage medium having a predetermined Curie point permitting said copy medium to be in a paramagnetic state while said first and second layers remain in a ferromagnetic state.
Claim 18
Dependent Claim
99 words
A method as in claim 12 wherein the copying of the magnetic recording on the intermediate storage carrier onto said copy storage medium comprises the steps of: placing the first layer of said intermediate carrier in contact with said copy storage medium while said copy storage medium is in a paramagnetic state and maintaining that contact while the copy storage medium reverts to a ferromagnetic state, said first layer and said copy storage medium having predetermined Curie points permitting said copy medium to be in a paramagnetic state while said first and second layers remain in a ferromagnetic state.
References Cited (Backward Citations)
US3496304A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-10-17 | 1976-04-17 | 1976-10-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-10-17 | 1980-04-17 | 1980-10-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-10-17 | 1984-04-17 | 1984-10-17 | $7700.00 | Window Closed / Lapsed |