US4685371A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Grand piano action
Assignee: Individual
•
Filing: 1985-06-12
•
Granted: 1987-08-11
•
Expires: 2005-06-12
Abstract
Abstract Within each action of a grand piano there are certain wood surfaces which rub against other surfaces. These interfaces create friction, which adversely affects the playability of the piano. In order to reduce and overcome this friction, strips of fluorocarbon resin, having an extremely low coefficient of friction, are adhered to those wooden surfaces within the action which come into contact with other surfaces.
Inventors
- 👤 Gary M. Levinson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 06:32
CPC Classifications
G; G10; G10C; G10C3/00; G10C3/16; G10C3/22; G10C3/24; G10C9/00
Claims Analysis
Total Claims: 28
Claim 1
Independent Claim
99 words
A method of making a reduced friction action for a grand piano of the type which includes a repetition lever, key means for actuating said repetition lever and a knuckle, said method comprising the step of adhering a strip of film of a low friction polymeric material to that surface of said repetition lever which comes into contact with a surface at the knuckle when a key of said grand piano is struck to lower the friction between said surface and said repetition lever, to increase the responsiveness of the action, and to improve the longevity of the action.
Claim 2
Independent Claim
99 words
A method of making a reduced friction action for a grand piano of the type which includes a repetition lever, key means for actuating said repetition lever and a knuckle, said method comprising the step of adhering a strip of film of a low friction polymeric material to that surface of said repetition lever which comes into contact with a surface at the knuckle when a key of said grand piano is struck to lower the friction between said surface and said repetition lever, to increase the responsiveness of the action, and to improve the longevity of the action.
Claim 3
Dependent Claim
17 words
The method of claim 1 wherein said strip of low friction material is composed of fluorocarbon resins.
Claim 4
Dependent Claim
17 words
The method of claim 1 wherein said strip of low friction material is made from Teflon TFE.
Claim 5
Dependent Claim
17 words
The method of claim 1 wherein said strip of low friction material is made from Teflon FEP.
Claim 6
Independent Claim
92 words
A method of making a reduced friction action for a grand piano of the type which includes a jack, key means for actuating said jack and a knuckle, said method comprising adhering a strip of film of a low friction polymeric material to those surfaces of said jack which come into contact with the surface of the knuckle when a key of said grand piano is struck to lower the friction between said knuckle and said jack, to increase the responsiveness of said action and to improve the longevity of said action.
Claim 7
Independent Claim
92 words
A method of making a reduced friction action for a grand piano of the type which includes a jack, key means for actuating said jack and a knuckle, said method comprising adhering a strip of film of a low friction polymeric material to those surfaces of said jack which come into contact with the surface of the knuckle when a key of said grand piano is struck to lower the friction between said knuckle and said jack, to increase the responsiveness of said action and to improve the longevity of said action.
Claim 8
Dependent Claim
17 words
The method of claim 5 wherein said strip of low friction material is composed of fluorocarbon resin.
Claim 9
Dependent Claim
18 words
The method of claim 5 wherein said strip of low friction material is made from the Teflon TFE.
Claim 10
Dependent Claim
17 words
The method of claim 5 wherein said strip of low friction material is made from Teflon FEP.
Claim 11
Dependent Claim
64 words
A method as in claim 5 wherein said adhering of said strip is done by adhering said low friction material to the uppermost surface of said jack and extending said material downwardly on two surfaces of said jack a distance slightly in excess of the interface between said jack and the knuckle within said action when the key of said grand piano is struck.
Claim 12
Dependent Claim
17 words
The method of claim 9 wherein said strip of low friction material is composed of fluorocarbon resin.
Claim 13
Dependent Claim
17 words
The method of claim 9 wherein said strip of low friction material is made from Teflon TFE.
Claim 14
Dependent Claim
17 words
The method of claim 9 wherein said strip off low friction material is made from Teflon FEP.
Claim 15
Independent Claim
106 words
A method of making a reduced friction action for a grand piano of the type which includes a jack; a repetition lever, key means for actuating said jack and repetition lever, and a knuckle, said method comprising the steps of adhering strips of film of a low friction polymeric material to those surfaces of the jack and repetition lever which come into contact with the surface of the knuckle when a key of said grand piano is struck to lower the friction between the knuckle, and the jack and repetition lever, to increase the responsiveness of said action and to improve the longevity of said action.
Claim 16
Independent Claim
106 words
A method of making a reduced friction action for a grand piano of the type which includes a jack; a repetition lever, key means for actuating said jack and repetition lever, and a knuckle, said method comprising the steps of adhering strips of film of a low friction polymeric material to those surfaces of the jack and repetition lever which come into contact with the surface of the knuckle when a key of said grand piano is struck to lower the friction between the knuckle, and the jack and repetition lever, to increase the responsiveness of said action and to improve the longevity of said action.
Claim 17
Dependent Claim
17 words
The method of claim 13 wherein said strip of low friction material is composed of fluorocarbon resin.
Claim 18
Dependent Claim
17 words
The method of claim 13 wherein said strip of low friction material is made from Teflon TFE.
Claim 19
Dependent Claim
17 words
The method of claim 13 wherein said strip for low friction material is made from Teflon FEP.
Claim 20
Dependent Claim
113 words
In a reduced friction action for a grand piano of the type which includes a jack, a repetition lever, key means for actuating said jack and lever, a hammer, a tender, a let off regulating screw, and a knuckle, said key means comprising a plurality of keys, the improvement comprising a strip of film of a low friction polymeric material disposed on the surface of the jack which comes into contact with a surface on the knuckle when one of said keys of said grand piano is struck to lower the friction between said jack and said knuckle, to increase the responsiveness of said action and to improve the longevity of said action.
Claim 21
Dependent Claim
113 words
In a reduced friction action for a grand piano of the type which includes a jack, a repetition lever, key means for actuating said jack and lever, a hammer, a tender, a let off regulating screw, and a knuckle, said key means comprising a plurality of keys, the improvement comprising a strip of film of a low friction polymeric material disposed on the surface of the jack which comes into contact with a surface on the knuckle when one of said keys of said grand piano is struck to lower the friction between said jack and said knuckle, to increase the responsiveness of said action and to improve the longevity of said action.
Claim 22
Dependent Claim
45 words
Apparatus as in claim 17, wherein said low friction material is disposed on a top surface of said jack and is integral with extensions of said low friction material which are disposed on two adjacent sides of said jack and secured thereto by an adhesive.
Claim 23
Dependent Claim
15 words
Apparatus as in claim 17, wherein said strip of low friction material comprises fluorocarbon resin.
Claim 24
Dependent Claim
43 words
Apparatus as in claim 17, wherein the improvement further comprises a strip of low friction material disposed on a surface of said repetition lever which comes into contact with the surface of the knuckle when a key of said grand piano is struck.
Claim 25
Dependent Claim
67 words
Apparatus as in claim 20, wherein said strip of low friction material adhered to said repetition lever is a bifurcated strip having two branches, each of said branches being disposed on respective edge surfaces on the top of said repetition lever, said edge surfaces being disposed on opposite sides of said jack and said strip of low friction material being adhered to said surfaces by an adhesive.
Claim 26
Dependent Claim
48 words
Apparatus as in claim 20, wherein the improvement further comprises a strip of low friction material disposed on a surface of said tender which comes into contact with the lowermost surface of said let off regulating screw when one of said keys of said grand piano is struck.
Claim 27
Dependent Claim
17 words
Apparatus as in claim 22, wherein said strips of low friction material are composed of fluorocarbon resin.
Claim 28
Dependent Claim
11 words
Apparatus as in claim 23, wherein said fluorocarbon resin is Teflon.
References Cited (Backward Citations)
US2172253A
Cited
US2334444A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-08-10 | 1991-02-09 | 1991-08-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-08-10 | 1995-02-09 | 1995-08-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-08-10 | 1999-02-09 | 1999-08-11 | $7700.00 | Window Closed / Lapsed |