Patent US3704841A successfully refreshed from Google Patents.
US3704841A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Magnetic tape cartridge
Assignee: Memorex Corp
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Filing: 1971-01-28
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Granted: 1972-12-05
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Expires: 1991-01-28
Abstract
Abstract An improved tape cartridge of moulded plastic having opposing tape reel viewing windows with internally projecting annular ridges fabricated around the periphery of spindle holes in the windows, the annular ridges being fabricated with relief slots for eliminating cracking of the windows during use.
Inventors
- 👤 Keith S Brown
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-10 02:00
CPC Classifications
G; G11; G11B; G11B23/00; G11B23/02; G11B23/04; G11B23/08; G11B23/087; G11B23/08707; G11B23/0875
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
45 words
An improved magnetic tape cartridge having at least one viewing window with internally projecting annular ridges fabricated around the periphery of tape-reel spindle holes in the window wherein the annular ridges are fabricated with at least one relief slot for eliminating cracking of the window.
Claim 2
Dependent Claim
45 words
An improved magnetic tape cartridge having at least one viewing window with internally projecting annular ridges fabricated around the periphery of tape-reel spindle holes in the window wherein the annular ridges are fabricated with at least one relief slot for eliminating cracking of the window.
Claim 3
Dependent Claim
46 words
An improved magnetic tape cartridge having opposed tape reel viewing windows with internally projecting annular ridges around the periphery of the two tape-reel spindle holes in each window, wherein the annular ridges are each fabricated with pairs of relief slots for eliminating cracking of the window.
Claim 4
Dependent Claim
46 words
An improved magnetic tape cartridge having opposed tape reel viewing windows with internally projecting annular ridges around the periphery of the two tape-reel spindle holes in each window, wherein the annular ridges are each fabricated with pairs of relief slots for eliminating cracking of the window.
Claim 5
Dependent Claim
26 words
The tape cartridge of claim 2 wherein the pairs of relief slots are aligned along the mutual centerline of the tape-reel spindle holes on each window.
Claim 6
Dependent Claim
21 words
The tape cartridge of claim 3 wherein the relief slots are cut to a depth two-thirds the height of the ridges.
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) | 1975-12-05 | 1976-06-05 | 1976-12-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-12-05 | 1980-06-05 | 1980-12-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-12-05 | 1984-06-05 | 1984-12-05 | $7700.00 | Window Closed / Lapsed |