Patent FR464374A successfully refreshed from Google Patents.
US4152967A
Expired / Lapsed
US
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Pneumatic piano action
Assignee: Individual
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Filing: 1977-08-25
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Granted: 1979-05-08
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Expires: 1997-08-25
Abstract
Abstract An action for a piano type musical instrument in which the hammer striking force is produced by the reaction of a pneumatic piston. For the grand piano embodiment, the hammer pivot is carried by the key-lever and the piston is connected to the hammer butt such that when the instrument is played the resistance of the piston raises the hammer into the musical string. A similar action is shown for the upright piano. In each case the hammer is propelled into the string with a velocity proportional to key-lever velocity and the escape, check and repetition parts of conventional actions are made unnecessary by the inherent properties of the pneumatic piston.
Inventors
- 👤 Ellis Barron
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 21:06
CPC Classifications
G; G10; G10C; G10C3/00; G10C3/16; G10C3/20; G10C3/18; G10C3/22
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
92 words
An action for a keyboard type musical instrument, comprising: (a) a hammer having a hammer butt and a hammer pivot; (b) a key-lever; (c) a piston; (d) a closed cylinder fixed in the instrument and slideably containing said piston, the combination providing a velocity dependent resistance force; and (e) means including flexible cord means interconnecting said piston, said hammer butt, and said key-lever such that key-lever motion causes movement of the hammer to strike a musical element in the instrument, said hammer movement acting in opposition to said velocity dependent resistance force.
Claim 2
Dependent Claim
92 words
An action for a keyboard type musical instrument, comprising: (a) a hammer having a hammer butt and a hammer pivot; (b) a key-lever; (c) a piston; (d) a closed cylinder fixed in the instrument and slideably containing said piston, the combination providing a velocity dependent resistance force; and (e) means including flexible cord means interconnecting said piston, said hammer butt, and said key-lever such that key-lever motion causes movement of the hammer to strike a musical element in the instrument, said hammer movement acting in opposition to said velocity dependent resistance force.
Claim 3
Dependent Claim
28 words
An action as in claim 1, wherein said piston is provided with a hole therein and a cover thereon, the combination acting as a gravity sensitive flap valve.
Claim 4
Dependent Claim
55 words
An action as in claim 1, wherein said hammer pivot is mounted on said key-lever, said hammer butt has a pulley mounted thereon, and said cord means includes a cord led over said pulley with one end of the cord fixed in said instrument and the other end of the cord connected to said piston.
Claim 5
Dependent Claim
60 words
An action as in claim 1, wherein said hammer pivot is mounted on a fixed portion of said instrument, said key-lever has a pulley mounted thereon, and said flexible cord means includes a cord led over said pulley with one end of the cord connected to said piston and the other end of said cord connected to said hammer butt.
Claim 6
Dependent Claim
14 words
A action as in claim 1, wherein said cylinder contains an incompressible bluid therein.
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) | 1982-05-07 | 1982-11-06 | 1983-05-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-05-07 | 1986-11-06 | 1987-05-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-05-07 | 1990-11-06 | 1991-05-08 | $7700.00 | Window Closed / Lapsed |