Patent US4130221A successfully refreshed from Google Patents.
US4130221A
Expired / Lapsed
US
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Torsion spring door for a videocassette
Assignee: 3M Co
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Filing: 1978-02-06
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Granted: 1978-12-19
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Expires: 1998-02-06
Abstract
Abstract A torsion spring for biasing closed the door of a videocassette. A central portion of the spring provides the hinge pin for pivotably mounting the door, while its two ends are fixed respectively to the door and housing.
Inventors
- 👤 Clyde V. Peterson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 06:40
CPC Classifications
G; G11; G11B; G11B23/00; G11B23/02; G11B23/04; G11B23/041; G11B23/045
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
206 words
In a videocassette comprising a length of magnetizable recording tape; two reels each supporting a different helically wound end portion of said tape; a generally rectangular housing enclosing and supporting said reels for rotation to transfer tape between said reels, said housing including an outer front wall having generally planar end portions, a recessed portion between said end portions and means for guiding tape between said reels through said outer wall and across said recessed portion to provide a tape access area; a door; a hinge assembly for pivotably mounting said door on said housing for movement between a closed position over said tape access area and an open position spaced from said tape access area comprising a hinge plate fixed to said housing, arcuate generally hollow cylindrical axially aligned side portions of said door and said hinge plate, and a hinge pin extending through said side portions; and a spring for biasing said door to its closed position, the improvement wherein: said spring is a torsion spring including a straight central portion extending through the side portions of said door and hinge plate to provide said hinge pin, a first end portion fixed to said door, and a second end portion fixed to said housing.
Claim 2
Dependent Claim
206 words
In a videocassette comprising a length of magnetizable recording tape; two reels each supporting a different helically wound end portion of said tape; a generally rectangular housing enclosing and supporting said reels for rotation to transfer tape between said reels, said housing including an outer front wall having generally planar end portions, a recessed portion between said end portions and means for guiding tape between said reels through said outer wall and across said recessed portion to provide a tape access area; a door; a hinge assembly for pivotably mounting said door on said housing for movement between a closed position over said tape access area and an open position spaced from said tape access area comprising a hinge plate fixed to said housing, arcuate generally hollow cylindrical axially aligned side portions of said door and said hinge plate, and a hinge pin extending through said side portions; and a spring for biasing said door to its closed position, the improvement wherein: said spring is a torsion spring including a straight central portion extending through the side portions of said door and hinge plate to provide said hinge pin, a first end portion fixed to said door, and a second end portion fixed to said housing.
Claim 3
Dependent Claim
61 words
A videocassette according to claim 1, wherein the end portions of said torsion spring extend at generally right angles to its central portion, said second end portion is fixed to said housing by being retained between said hinge plate and said housing and said first end portion is fixed to said door at a position spaced from its arcuate side portion.
References Cited (Backward Citations)
US3187925A
Cited
US3809219A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-12-18 | 1982-06-19 | 1982-12-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-12-18 | 1986-06-19 | 1986-12-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-12-18 | 1990-06-19 | 1990-12-19 | $7700.00 | Window Closed / Lapsed |