Patent US4855740A successfully refreshed from Google Patents.
US4855740A
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Keyboard
Assignee: Yamaha Corp
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Filing: 1987-09-25
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Granted: 1989-08-08
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Expires: 2007-09-25
Abstract
Abstract In construction of a keyboard for word processors and computer machines, character patterns of different key arrangement modes are stored in different memories for selective read-out so that any key arrangement mode chosen by an operator should be visually indicated on keys, thereby enabling use of a keyboard in various modes.
Inventors
- 👤 Toshihiro Muramatsu
- 👤 Kenzaburou Iijima
- 👤 Yoshinori Hayashi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 15:27
CPC Classifications
G; G06; G06F; G06F3/00; G06F3/01; G06F3/02; G06F3/023; G06F3/0238
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
171 words
An improved keyboard comprising a plurality of keys arranged in a matrix array for displaying selected character patterns, a character pattern indicator mounted atop each of said keys, each of said character pattern indicators including a plurality of dot indicators arranged in a matrix array for forming an image of a selected character pattern, a plurality of memories each storing a series of character patterns of a key arrangement mode, selecting means for selecting one of said memories in accordance with operator's instruction, and transmitting means for transmitting a series of character patterns from one of said memories to corresponding ones of said character pattern indicators for visual indication of said character patterns by selected ones of said dot indicators, said transmitting means including a single multiplexer for sequentially transmitting said character patterns from one of said memories to each of said character pattern indicators of said keyboard at a sufficient rate whereby a viewer has the visual impression that said character patterns are concurrently received by said character pattern indicators.
Claim 2
Dependent Claim
171 words
An improved keyboard comprising a plurality of keys arranged in a matrix array for displaying selected character patterns, a character pattern indicator mounted atop each of said keys, each of said character pattern indicators including a plurality of dot indicators arranged in a matrix array for forming an image of a selected character pattern, a plurality of memories each storing a series of character patterns of a key arrangement mode, selecting means for selecting one of said memories in accordance with operator's instruction, and transmitting means for transmitting a series of character patterns from one of said memories to corresponding ones of said character pattern indicators for visual indication of said character patterns by selected ones of said dot indicators, said transmitting means including a single multiplexer for sequentially transmitting said character patterns from one of said memories to each of said character pattern indicators of said keyboard at a sufficient rate whereby a viewer has the visual impression that said character patterns are concurrently received by said character pattern indicators.
Claim 3
Dependent Claim
44 words
An improved keyboard as claimed in claim 1 in which said transmitting means includes a luminescence drive circuit connected to said memories, a luminant array connected to said luminescence drive circuit and said single multiplexer interposed between said luminant array and said dot indicators.
Claim 4
Dependent Claim
47 words
An improved keyboard as claimed in claim 1 in which said transmitting means includes a luminescence drive circuit connected to said memories, a plurality of luminant arrays each connected to each said key and said single multiplexer interposed between said luminescence drive circuit and said luminant arrays.
References Cited (Backward Citations)
US4531119A
Cited
US4459581A
Cited
JPS5977539A
Cited
US4551717A
Cited
US4544276A
Cited
US4602878A
Cited
DE3338047A1
Cited
JPS60146316A
Cited
DE3409980A1
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-08-07 | 1993-02-06 | 1993-08-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-08-07 | 1997-02-06 | 1997-08-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-08-07 | 2001-02-06 | 2001-08-08 | $7700.00 | Window Closed / Lapsed |