US5066842A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Key top
Assignee: Alps Alpine Co Ltd
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Filing: 1990-07-30
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Granted: 1991-11-19
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Expires: 2010-07-30
Abstract
Abstract A key top, of the type utilized in keyboards, is disclosed, which minimizes the lateral stress encountered by the central engaging protrusion with respect to the underlying switch. Two T-shaped reinforcing rib structures are provided on bottom surface of the top plate of the key top, with the rib structures spaced apart from the engaging protrusion, thereby providing a gap between the reinforcing ribs and the engaging protrusion, and thus dispersing lateral stress on the engaging protrusion through increased flexure of the engaging protrusion. In addition, the base of the engaging protrusion is thickened to structurally resist lateral stress.
Inventors
- 👤 Kazuyoshi Yamagata
- 👤 Masaaki Kageyama
- 👤 Kyoichi Kaneko
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 17:00
CPC Classifications
H; H01; H01H; H01H13/00; H01H13/02; H01H13/12; H01H13/14; H01H3/00; H01H3/02; H01H3/12; H01H2233/00; H01H2233/07
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
89 words
A key top comprising: a top plate having top and bottom surfaces; an engaging protrusion extending from said bottom surface of said top plate and disposed at the approximately central portion of said bottom surface of said top plate, said engaging protrusion terminating in a free end; and a plurality of reinforcing ribs extending from said bottom surface of said top plate and disposed adjacent to said engaging protrusion, characterized in that at least two gaps are disposed between said engaging protrusion and at least two of said ribs.
Claim 2
Dependent Claim
89 words
A key top comprising: a top plate having top and bottom surfaces; an engaging protrusion extending from said bottom surface of said top plate and disposed at the approximately central portion of said bottom surface of said top plate, said engaging protrusion terminating in a free end; and a plurality of reinforcing ribs extending from said bottom surface of said top plate and disposed adjacent to said engaging protrusion, characterized in that at least two gaps are disposed between said engaging protrusion and at least two of said ribs.
Claim 3
Dependent Claim
69 words
A key top according to claim 1, wherein said engaging protrusion includes walls and said walls have a first predetermined thickness at the free end of said engaging protrusion, and further wherein the thickness of said walls adjacent to said gaps becomes increasingly greater than said first predetermined thickness as the distance from said free end of said engaging protrusion to said bottom surface of said top plate decreases.
Claim 4
Dependent Claim
16 words
A key top according to claim 2, wherein said ribs adjacent to said gaps are T-shaped.
Claim 5
Dependent Claim
16 words
A key top according to claim 1, wherein said ribs adjacent to said gaps are T-shaped.
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) | 1994-11-18 | 1995-05-20 | 1995-11-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-11-18 | 1999-05-20 | 1999-11-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-11-18 | 2003-05-20 | 2003-11-19 | $7700.00 | Window Closed / Lapsed |