Patent US4038693A successfully refreshed from Google Patents.
US4038693A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Anti-static magnetic record disk assembly
Assignee: International Business Machines Corp
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Filing: 1975-09-23
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Granted: 1977-07-26
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Expires: 1995-09-23
Abstract
Abstract A rotary magnetic record disk assembly comprising a magnetic disk which is rotatably disposed within a containing jacket of material of high electrically insulating characteristics. An electrically conductive layer is disposed on the inside surface of the jacket for draining away electrostatic charge on the jacket.
Inventors
- 👤 Coy Lee Huffine
- 👤 Larry Frederick Mattson
- 👤 Karl Allen Shidler
- 👤 Norman Edward Slindee
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 23:54
CPC Classifications
G; G11; G11B; G11B23/00; G11B23/50; G11B23/505; B; B29; B29B; B29B9/00; B30; B30B; B30B11/00; B30B11/20; B30B11/201
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
149 words
A magnetic record assembly including: a magnetic disk of highly electrically insulating, flat, uniform thickness sheet material, a jacket of highly electrically insulating material enclosing said disk and having a central opening through it by means of which the disk may be rotatably driven within the jacket and having a slot therein for receiving a magnetic transducer to have a data transferring relationship with the disk and having flat internal faces adjacent to and extending along the faces of said disk, a layer of a porous low friction dusting fabric within said jacket and in wiping contact with the faces of said disk as the disk rotates within the jacket, and a uniform thickness flat thin layer of electrically conducting non-porous material within said jacket and in contact with and between said flat internal jacket faces and said layer of dusting fabric for draining static electricity from the jacket.
Claim 2
Dependent Claim
149 words
A magnetic record assembly including: a magnetic disk of highly electrically insulating, flat, uniform thickness sheet material, a jacket of highly electrically insulating material enclosing said disk and having a central opening through it by means of which the disk may be rotatably driven within the jacket and having a slot therein for receiving a magnetic transducer to have a data transferring relationship with the disk and having flat internal faces adjacent to and extending along the faces of said disk, a layer of a porous low friction dusting fabric within said jacket and in wiping contact with the faces of said disk as the disk rotates within the jacket, and a uniform thickness flat thin layer of electrically conducting non-porous material within said jacket and in contact with and between said flat internal jacket faces and said layer of dusting fabric for draining static electricity from the jacket.
Claim 3
Dependent Claim
31 words
A magnetic record assembly as set forth in claim 1, said layer of electrically conducting non-porous material completely surrounding said central opening of said jacket and also completely surrounding said slot.
Claim 4
Dependent Claim
43 words
A magnetic record assembly as set forth in claim 1, said layer of electrically conducting non-porous material constituting an ink on said inner surfaces of said jacket which in dry conditions has a resistivity less than 1 × 10 8 ohms per square.
Claim 5
Dependent Claim
162 words
In a magnetic record assembly which includes a magnetic disk of highly electrically insulating, flat, uniform thickness sheet material, a jacket of highly electrically insulating material enclosing said disk and having a central opening through it by means of which the disk may be rotatably driven within the jacket and having a slot therein for receiving a magnetic transducer to have a data transferring relationship with the disk and having flat internal faces adjacent to and extending along the faces of said disk, and a layer of a porous, low friction dusting fabric within said jacket and in wiping contact with the faces of said disk as the disk rotates within the jacket, the improvement which comprises: the provision of a uniform thickness thin layer of electrically conducting non-porous material positioned within said jacket and in contact with and between said flat internal jacket faces and said layer of dusting fabric for the purpose of draining off static electricity from the jacket.
Claim 6
Dependent Claim
162 words
In a magnetic record assembly which includes a magnetic disk of highly electrically insulating, flat, uniform thickness sheet material, a jacket of highly electrically insulating material enclosing said disk and having a central opening through it by means of which the disk may be rotatably driven within the jacket and having a slot therein for receiving a magnetic transducer to have a data transferring relationship with the disk and having flat internal faces adjacent to and extending along the faces of said disk, and a layer of a porous, low friction dusting fabric within said jacket and in wiping contact with the faces of said disk as the disk rotates within the jacket, the improvement which comprises: the provision of a uniform thickness thin layer of electrically conducting non-porous material positioned within said jacket and in contact with and between said flat internal jacket faces and said layer of dusting fabric for the purpose of draining off static electricity from the jacket.
References Cited (Backward Citations)
US3440091A
Cited
US3532932A
Cited
US3958066A
Cited
US3932710A
Cited
US3864755A
Cited
US3931644A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-07-25 | 1981-01-24 | 1981-07-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-07-25 | 1985-01-24 | 1985-07-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-07-25 | 1989-01-24 | 1989-07-26 | $7700.00 | Window Closed / Lapsed |