US4564850A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Radiation-sensitive record disc with improved internal structure
Assignee: Toshiba Corp
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Filing: 1983-11-08
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Granted: 1986-01-14
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Expires: 2003-11-08
Abstract
Abstract A radiation-sensitive record disc is disclosed having a first disc and a second disc coaxially positioned adjacent the first disc to reinforce the first disc. A first spacer is positioned between the first and second discs for fixedly connecting the discs together and to form an air space between the discs. A recording layer is formed on one surface of the first or second discs within the air space. A second spacer is radially displaced from the first spacer, and positioned between the first and second discs. This second spacer enables the discs to move relative to each other in a radial direction in response to expansion or contraction of at least one of the discs due to changes in temperature, humidity, atmospheric pressure, etc.
Inventors
- 👤 Odawara Kazuharu
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 13:32
CPC Classifications
G; G11; G11B; G11B7/00; G11B7/24; G11B7/24015
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
143 words
A radiation-sensitive record disc comprising: a first disc member; a second disc member coaxially positioned adjacent said first disc member to reinforce said first disc member; first spacing means between said first and second disc members for fixedly connecting said disc members together to form an air space between said disc members; a recording layer formed on one surface of said first or second disc members in the air space between said disc members; and second spacing means radially displaced from said first spacing means and between said first and second disc members to form said air space, said second spacing means slidably contacting at least one of said first and second disc members for enabling said disc members to move relative to each other in a radial direction in response to expansion or contraction of at least one of said disc members.
Claim 2
Dependent Claim
143 words
A radiation-sensitive record disc comprising: a first disc member; a second disc member coaxially positioned adjacent said first disc member to reinforce said first disc member; first spacing means between said first and second disc members for fixedly connecting said disc members together to form an air space between said disc members; a recording layer formed on one surface of said first or second disc members in the air space between said disc members; and second spacing means radially displaced from said first spacing means and between said first and second disc members to form said air space, said second spacing means slidably contacting at least one of said first and second disc members for enabling said disc members to move relative to each other in a radial direction in response to expansion or contraction of at least one of said disc members.
Claim 3
Dependent Claim
135 words
The radiation-sensitive record disc of claim 1 further comprising a third disc member coaxially positioned adjacent said second disc member on a side opposite said first disc member, third spacing means radially displaced from said second spacing means and between said second and third disc members for fixedly connecting said second and third disc members together to form a second air space and a recording layer formed on one surface of said second or third disc members in the second air space, said second spacing means further extending between said second and third disc members to form said second air space, said second spacing means slidably contacting at least one of said second or third disc members for enabling said second and third disc members to move relative to each other in a radial direction.
Claim 4
Dependent Claim
21 words
The radiation-sensitive record disc of claim 2 wherein said second disc member has a thickness greater than said first disc member.
Claim 5
Dependent Claim
38 words
The radiation-sensitive record disc of claim 2 wherein said first and third spacing means comprise a pair of concentric inner annular spacers bonded between said second disc member and each of said first and third disc members, respectively.
Claim 6
Dependent Claim
43 words
The radiation-sensitive record disc of claim 2 wherein said second spacing means comprises an outer annular spacer bonded between said first and third disc members, said annular spacer having a groove facing said second disc member to slidably receive said second disc member.
Claim 7
Dependent Claim
38 words
The radiation-sensitive record disc of claim 1 wherein said second spacing means forms an annular gap outside the outer peripheral surface of said second disc member to permit movement of said second disc member in the radial direction.
Claim 8
Dependent Claim
40 words
The radiation-sensitive record disc of claim 1 wherein said second spacing means comprises an outer annular spacer bonded to said first disc member and having a first groove facing said second disc member to slidably receive said second disc member.
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) | 1989-01-13 | 1989-07-15 | 1990-01-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-01-13 | 1993-07-15 | 1994-01-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-01-13 | 1997-07-15 | 1998-01-14 | $7700.00 | Window Closed / Lapsed |