US4562764A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electronic musical performance
Assignee: HDC Young Chang Co Ltd
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Filing: 1984-06-08
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Granted: 1986-01-07
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Expires: 2004-06-08
Abstract
Abstract A keyboard for an electronic music instrument is made to have a "piano key feel" by bracketing an end of each key with the legs of a weighted A-shaped action arm which pivots about a single point and actuates a leaf spring switch.
Inventors
- 👤 Neal Marshall
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 22:12
CPC Classifications
G; G10; G10H; G10H1/00; G10H1/32; G10H1/34; G10H1/344; G10H1/346; Y; Y10; Y10S; Y10S84/00; Y10S84/07
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
117 words
In combination with a keyboard having an array of pivoted keys, an action arm assembly for interacting with each keyboard key and comprising: (a) means defining a pivotal action arm and pivot defining means therefor associated with each key, (b) means defining a weighting of each action arm, (c) means defining spring extensions of the action arm bracketing the associated key with one such spring constructed to yield initially on key depression and restore so that the action arm pivots, (d) means for converting action arm movement into a key-movement-related signal and wherein the action arm has an A-yoke form with a weighted A-bar and legs defining said springs as leaf-form springs for bracketing a key end.
Claim 2
Dependent Claim
117 words
In combination with a keyboard having an array of pivoted keys, an action arm assembly for interacting with each keyboard key and comprising: (a) means defining a pivotal action arm and pivot defining means therefor associated with each key, (b) means defining a weighting of each action arm, (c) means defining spring extensions of the action arm bracketing the associated key with one such spring constructed to yield initially on key depression and restore so that the action arm pivots, (d) means for converting action arm movement into a key-movement-related signal and wherein the action arm has an A-yoke form with a weighted A-bar and legs defining said springs as leaf-form springs for bracketing a key end.
Claim 3
Dependent Claim
22 words
Apparatus in accordance with claim 1 wherein the spring leg for encountering initial key movememt is shorter than the other spring leg.
References Cited (Backward Citations)
US3927594A
Cited
US4111091A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-01-06 | 1989-07-08 | 1990-01-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-01-06 | 1993-07-08 | 1994-01-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-01-06 | 1997-07-08 | 1998-01-07 | $7700.00 | Window Closed / Lapsed |