US4052750A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Flexible recording disk with improved spindle mounting means
Assignee: Xidex Corp
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Filing: 1975-12-05
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Granted: 1977-10-04
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Expires: 1995-12-05
Abstract
Abstract An improved flexible magnetic recording disc assembly comprising an envelope and a flexible recording disc rotatably received in the envelope, the disc having an annular reinforcement member concentrically arranged adjacent the central mounting aperture of the disc. Two embodiments are disclosed: a first having a single annular reinforcement member secured to the spindle side of the flexible disc; and a second having a pair of annular reinforcement members disposed on opposite surfaces of the disc. The reinforcement member has an axial thickness in the range from about 2 to about 7 mils to provide sufficient structural rigidity to resist crinkling and flaring during use; a static and dynamic coefficient of friction not less than about 0.3, and a total electrical resistance measured in the longitudinal axial direction in the range of about 1 ohm to about 50 megohms to facilitate dissipation of static electrical charges which may build up on the recording surfaces of the disc. The reinforcement member is adhered to the flexible disc by means of a cement which is preferably electrically conductive, also to promote static charge dissipation.
Inventors
- 👤 John A. Barber
- 👤 C. Norman Dion
- 👤 Richard N. James
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 11:38
CPC Classifications
G; G11; G11B; G11B17/00; G11B17/02; G11B17/022; G11B17/028; G11B17/03; G11B17/32; G11B23/00; G11B23/50; G11B23/505
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
109 words
In a flexible disc assembly comprising a flexible disc having a pliant substrate and at least one recording layer on said substrate, said disc having a central aperture adapted to receive a rotatable drive spindle, and a jacket substantially enclosing said flexible disc and permitting rotation of said flexible disc therewithin, the improvement comprising reinforcement means adhered to at least one surface of said disc adjacent said central aperture for preventing deformation of said disk in the region of said central aperture and for protecting said recording layer, said reinforcement means being fabricated from a material having sufficient electrical conductivity to prevent accumulation of electrical charges on said disc.
Claim 2
Dependent Claim
109 words
In a flexible disc assembly comprising a flexible disc having a pliant substrate and at least one recording layer on said substrate, said disc having a central aperture adapted to receive a rotatable drive spindle, and a jacket substantially enclosing said flexible disc and permitting rotation of said flexible disc therewithin, the improvement comprising reinforcement means adhered to at least one surface of said disc adjacent said central aperture for preventing deformation of said disk in the region of said central aperture and for protecting said recording layer, said reinforcement means being fabricated from a material having sufficient electrical conductivity to prevent accumulation of electrical charges on said disc.
Claim 3
Dependent Claim
25 words
The apparatus of claim 1 wherein said reinforcement means has a total electrical resistance in the range from about 1 ohm to about 50 megohms.
Claim 4
Dependent Claim
30 words
The apparatus of claim 1 wherein said reinforcement means is fabricated from a material having sufficient frictional resistance to enable said disk to be rotated by said rotatable drive spindle.
Claim 5
Dependent Claim
19 words
The apparatus of claim 3 wherein said material has a static coefficient of friction not less than about 0.3.
Claim 6
Dependent Claim
19 words
The apparatus of claim 3 wherein said material has a coefficient of sliding friction not less than about 0.3.
Claim 7
Dependent Claim
35 words
The apparatus of claim 1 wherein said reinforcement means comprises an annular member arranged substantially concentrically with said central aperture and an adhesive compound for adhering said annular member to said disc in said region.
Claim 8
Dependent Claim
12 words
The apparatus of claim 6 wherein said adhesive compound is electrically conductive.
Claim 9
Dependent Claim
29 words
The apparatus of claim 1 wherein said reinforcement means comprises a pair of annular members each arranged substantially concentrically with said central aperture on opposite surfaces of said disc.
Claim 10
Independent Claim
107 words
A method of fabricating an improved flexible recording disc assembly of the type comprising a flexible disc having a pliant substrate and at least one recording layer on said substrate, said disk having a central aperture adapted to receive a rotatable drive spindle and a jacket substantially enclosing said flexible disc and permitting rotation of said flexible disk therewith, said method comprising the steps of: a. providing a reinforcement member having sufficient electrical conductivity to prevent accumulation of electrical charges on said disc when adhered thereto and predetermined frictional resistance characteristics; and b. adhering said reinforcement member to a surface of said disc adjacent said central aperture.
Claim 11
Independent Claim
107 words
A method of fabricating an improved flexible recording disc assembly of the type comprising a flexible disc having a pliant substrate and at least one recording layer on said substrate, said disk having a central aperture adapted to receive a rotatable drive spindle and a jacket substantially enclosing said flexible disc and permitting rotation of said flexible disk therewith, said method comprising the steps of: a. providing a reinforcement member having sufficient electrical conductivity to prevent accumulation of electrical charges on said disc when adhered thereto and predetermined frictional resistance characteristics; and b. adhering said reinforcement member to a surface of said disc adjacent said central aperture.
Claim 12
Dependent Claim
34 words
The method of claim 9 wherein said reinforcement member has an annular configuration, and said step (b) of adhering includes the step of arranging said annular reinforcement member substantially concentrically of said central aperture.
Claim 13
Dependent Claim
33 words
The method of claim 9 wherein said step (b) of adhering includes the steps of providing an adhesive compound and pressing said reinforcement member and said disk together with said adhesive compound therebetween.
Claim 14
Dependent Claim
12 words
The method of claim 11 wherein said adhesive compound is electrically conductive.
Claim 15
Dependent Claim
48 words
The method of claim 9 wherein said step (a) of providing includes the step of providing a pair of said reinforcement members, and said step (b) of adhering includes the step of adhering said pair of reinforcement members to opposed surfaces of said disc adjacent said central aperture.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-10-03 | 1981-04-04 | 1981-10-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-10-03 | 1985-04-04 | 1985-10-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-10-03 | 1989-04-04 | 1989-10-04 | $7700.00 | Window Closed / Lapsed |