US4781340A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Magnetic tape cassette
Assignee: TDK Corp
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Filing: 1984-03-14
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Granted: 1988-11-01
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Expires: 2004-03-14
Abstract
Abstract A magnetic tape cassette has a pair of tape reels contained in a lower casing in a rotatable manner and a leaf spring fixed to an upper casing to press down at the free end portions central projections of the tape reels, wherein the leaf spring is formed to have a substantially arcuate central portion and linear free end portions under non-loading condition, the free end portions being respectively in contact with the top of the central projection.
Inventors
- 👤 Haruo Shiba
- 👤 Masatoshi Okamura
- 👤 Makoto Saito
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 18:09
CPC Classifications
G; G11; G11B; G11B23/00; G11B23/02; G11B23/04; G11B23/08; G11B23/087
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
126 words
A magnetic tape cassette comprising an upper casing, a lower casing, a pair of tape reels contained in said lower casing in a rotatable manner and a leaf spring having two free ends, said leaf spring being fixed to said upper casing in a manner to press down central projections of said tape reels, wherein said leaf spring has a central portion, curved portions at both sides of said central portion, and linear free end portions at each of said free ends thereof under a nonloading condition, said free end portions being respectively in contact with the tops of said central projections, wherein the ratio of the total length of said leaf spring to the length of each said linear free end portions is about 1:0.08-0.25.
Claim 2
Dependent Claim
126 words
A magnetic tape cassette comprising an upper casing, a lower casing, a pair of tape reels contained in said lower casing in a rotatable manner and a leaf spring having two free ends, said leaf spring being fixed to said upper casing in a manner to press down central projections of said tape reels, wherein said leaf spring has a central portion, curved portions at both sides of said central portion, and linear free end portions at each of said free ends thereof under a nonloading condition, said free end portions being respectively in contact with the tops of said central projections, wherein the ratio of the total length of said leaf spring to the length of each said linear free end portions is about 1:0.08-0.25.
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) | 1991-11-01 | 1992-05-02 | 1992-11-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-11-01 | 1996-05-02 | 1996-11-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-11-01 | 2000-05-02 | 2000-11-01 | $7700.00 | Window Closed / Lapsed |