Patent US4101948A successfully refreshed from Google Patents.
US4101948A
Expired / Lapsed
US
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Method for cleaning flexible magnetic discs
Assignee: Fujifilm Holdings Corp
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Filing: 1976-12-21
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Granted: 1978-07-18
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Expires: 1996-12-21
Abstract
Abstract A soft, coarse, porous cleaning sheet 32 is adhered to the upper surface of a flat horizontal base plate 2, and has approximately the same configuration as the base plate. A floppy record disc 9 having a magnetic layer 10 is secured to the spindle 6 of a motor 5, and when the disc is rotated at a "below levitation" speed the layer 10 slidingly engages the cleaning sheet 32 and is scrape dusted clean thereby.
Inventors
- 👤 Eiichi Tadokoro
- 👤 Tatsuji Kitamoto
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 07:18
CPC Classifications
G; G11; G11B; G11B23/00; G11B23/50; G11B23/505
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
184 words
A cleaning method for a recording and reproducing apparatus of the type having a flat, horizontal base plate having a central aperture therein, a drive motor mounted beneath the base plate and having a rotary spindle extending up through the aperture, and a flexible record disc secured to the spindle for levitating rotation thereby parallel to and above the base plate, the record disc having a magnetic layer thereon on the side opposing the base plate, said method for cleaning the magnetic layer comprising: (a) disposing a soft, coarse, and porous sheet member on the base plate below the record disc, the sheet member having a central aperture therein corresponding to the base plate aperture (b) adhering the sheet member to the base plate, (c) rotating the record disc at a speed below its levitation speed, whereby the magnetic layer is slidingly contacted by the sheet member and cleaned thereby, dust particles adhering to the magnetic layer being scraped off by and transferred to the sheet member, and (d) removing the sheet member prior to recording or reproducing information on or from said disc.
Claim 2
Dependent Claim
184 words
A cleaning method for a recording and reproducing apparatus of the type having a flat, horizontal base plate having a central aperture therein, a drive motor mounted beneath the base plate and having a rotary spindle extending up through the aperture, and a flexible record disc secured to the spindle for levitating rotation thereby parallel to and above the base plate, the record disc having a magnetic layer thereon on the side opposing the base plate, said method for cleaning the magnetic layer comprising: (a) disposing a soft, coarse, and porous sheet member on the base plate below the record disc, the sheet member having a central aperture therein corresponding to the base plate aperture (b) adhering the sheet member to the base plate, (c) rotating the record disc at a speed below its levitation speed, whereby the magnetic layer is slidingly contacted by the sheet member and cleaned thereby, dust particles adhering to the magnetic layer being scraped off by and transferred to the sheet member, and (d) removing the sheet member prior to recording or reproducing information on or from said disc.
Claim 3
Dependent Claim
36 words
A cleaning method as recited in claim 1, wherein the thickness of the sheet member is approximately equal to the spacing between the record disc and the base plate when the record disc is rotationally levitated.
Claim 4
Dependent Claim
18 words
A cleaning method as recited in claim 2, wherein the sheet member is made of a non-woven fabric.
Claim 5
Dependent Claim
25 words
A cleaning method as recited in claim 2, wherein at least the upper surface of the sheet member is embossed in a concave-convex waffle pattern.
Claim 6
Dependent Claim
45 words
A cleaning method as recited in claim 2, wherein the outer configuration of the sheet member defines an area at least as large as that of the record disc, whereby the entire recording surface of the magnetic layer is slidingly contacted by the sheet member.
Claim 7
Dependent Claim
25 words
A cleaning method as recited in claim 1, wherein at least the upper surface of the sheet member is embossed in a concave-convex waffle pattern.
Claim 8
Dependent Claim
45 words
A cleaning method as recited in claim 1, wherein the outer configuration of the sheet member defines an area at least as large as that of the record disc, whereby the entire recording surface of the magnetic layer is slidingly contacted by the sheet member.
Claim 9
Dependent Claim
18 words
A cleaing method as recited in claim 1, wherein the sheet member is made of a non-woven fabric.
Claim 10
Dependent Claim
144 words
In a recording and reproducing apparatus of the type having a flat, horizontal base plate having a central aperture therein, a drive motor mounted beneath the base plate and having a rotary spindle extending up through the aperture, and a flexible record disc secured to the spindle for levitating rotation thereby parallel and above the base plate, said record disc having a magnetic layer thereon on the side opposing the base plate, a soft, coarse, porous sheet member disposed on the base plate below said record disc and having a central aperture therein corresponding to and aligned with the base plate aperture and means for releasably adhering the sheet member to said base plate whereby upon rotation of the record disc a speed below its levitation speed the magnetic layer will be disposed in sliding contact with the sheet member and be cleaned thereby.
Claim 11
Dependent Claim
144 words
In a recording and reproducing apparatus of the type having a flat, horizontal base plate having a central aperture therein, a drive motor mounted beneath the base plate and having a rotary spindle extending up through the aperture, and a flexible record disc secured to the spindle for levitating rotation thereby parallel and above the base plate, said record disc having a magnetic layer thereon on the side opposing the base plate, a soft, coarse, porous sheet member disposed on the base plate below said record disc and having a central aperture therein corresponding to and aligned with the base plate aperture and means for releasably adhering the sheet member to said base plate whereby upon rotation of the record disc a speed below its levitation speed the magnetic layer will be disposed in sliding contact with the sheet member and be cleaned thereby.
Claim 12
Dependent Claim
40 words
In a recording and reproducing apparatus as set forth in claim 9, wherein the thickness of the sheet member is approximately equal to the spacing between the record disc and the base plate when the record disc is rotatably levitated.
Claim 13
Dependent Claim
29 words
In a recording and reproducing apparatus as set forth in claim 10, wherein at least the upper surface of the sheet member is embossed in a concave-convex waffle pattern.
Claim 14
Dependent Claim
49 words
In a recording and reproducing apparatus as set forth in claim 10, wherein the outer configuration of the sheet member defines an area at least as large as that of the record disc, whereby the entire recording surface of the magnetic layer is slidingly contacted by the sheet member.
Claim 15
Dependent Claim
22 words
In a recording and reproducing apparatus as set forth in claim 10, wherein the sheet member is made of a non-woven fabric.
Claim 16
Dependent Claim
29 words
In a recording and reproducing apparatus as set forth in claim 9, wherein at least the upper surface of the sheet member is embossed in a concave-convex waffle pattern.
Claim 17
Dependent Claim
49 words
In a recording and reproducing apparatus as set forth in claim 9, wherein the outer configuration of the sheet member defines an area at least as large as that of the record disc, whereby the entire recording surface of the magnetic layer is slidingly contacted by the sheet member.
Claim 18
Dependent Claim
22 words
In a recording and reproducing apparatus as set forth in claim 9, wherein the sheet member is made of a non-woven fabric.
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) | 1981-07-17 | 1982-01-16 | 1982-07-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-07-17 | 1986-01-16 | 1986-07-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-07-17 | 1990-01-16 | 1990-07-18 | $7700.00 | Window Closed / Lapsed |