Soundboard for musical instruments

• US 5,469,769 A
• Filed: 06/26/1989
• Issued: 11/28/1995
• Est. Priority Date: 09/09/1983
• Status: Expired due to Fees

• Current Assignee: Yamaha Corporation
• Original Assignee: Yamaha Corporation
• Inventors: Sawada, Shuichi, Murase, Yoshihiko, Imagawa, Katsuhiko
• Primary Examiner(s): Franklin, Lawrence R.
• Application Number:
  US07/371,601
• Time in Patent Office: 2,346 Days
• Field of Search: 84/192-193
• US Class Current: 84/193
• CPC Class Codes: B32B 15/04 comprising metal as the main or only constituent of a layer, which is next to another layer of the same or of a different material next to a bituminous or tarry layer B32B11/08; next to a water-setting substance layer B32B13/06; next to a glass layer B32B17/061; next to a cellulosic plastic layer B32B23/042
• CPC Class Codes: B32B 15/20 comprising aluminium or copper B32B15/016 and B32B15/017 take precedence
• CPC Class Codes: B32B 21/04 comprising wood as the main or only constituent of a layer, which is next to another layer of the same or of a different material next to a layer of a particular substance B32B9/042; next to a bituminous or tarry layer B32B11/042; next to a water setting substance layer B32B13/10; next to a metal layer B32B15/10; next to a glass layer B32B17/062; next to a layer formed of natural mineral fibres or particles B32B19/042; next to a cellulosic plastic layer B32B23/044
• CPC Class Codes: B32B 2307/10 having particular acoustical properties
• CPC Class Codes: B32B 2311/18 Titanium
• CPC Class Codes: B32B 2311/24 Aluminium
• CPC Class Codes: B32B 2313/04 Carbon
• CPC Class Codes: B32B 2315/02 Ceramics
• CPC Class Codes: B32B 2315/085 Glass fiber cloth or fabric
• CPC Class Codes: B32B 2317/16 Wood, e.g. woodboard, fibreboard, woodchips
• CPC Class Codes: B32B 7/022 Mechanical properties
• CPC Class Codes: B32B 9/007 comprising carbon, e.g. graphite, composite carbon
• CPC Class Codes: G10C 3/06 Resonating means, e.g. soundboards or resonant strings; Fastenings thereof

Abstract

In a laminated construction of a soundboard for use in musical instruments such as the piano, the use of a core having larger shearing elastic modulus and/or smaller shearing loss tangent than that of the fore and rear plates assures small shearing loss in the treble range, and greatly improves the total tonal balance over the entire tonal range.

Claims

1. An improved soundboard for musical instruments comprising fore and rear plates, and

a core interposed between and bonded to said fore and rear plates and made of a material with a shearing elastic modulus greater than that of said fore and rear plates and with a shearing loss tangent that is less than that of said fore and rear plates, said shearing elastic modulus of said material for said core being less than 3.0×

10 dyne/cm.

3. An improved soundboard as claimed in claim 1 or 2 wherein said core is made of a material which is chosen from the group consisting of western red cedar, onoore kamba, aluminum, magnesium, titanium, graphite fiber-resin composites, glass fiber-resin composites and ceramics.

4. An improved soundboard as claimed in claim 1 or 2 in which

said shearing elastic modulus of said material for said core is 20% or more greater than that of said material for said fore and rear plates.

5. An improved soundboard as claimed in claim 4 in which said core is accompanied by at least one lamina made of a material chosen from a group consisting of woods, metals, ceramics, graphite fiber-resin composites and glass fiber-resin composites.

6. An improved soundboard as claimed in claim 4 in which said core is made of a material which is chosen from the group consisting of western red cedar, onoore kamba, aluminum, magnesium, titanium, graphite fiber-resin composites, glass fiber-resin composites and ceramics.

7. An improved soundboard as claimed in claim 6 in which said shearing loss tangent of said material for said core is 20% or more less than that of said material for said fore and rear plates.

8. An improved soundboard as claimed in claim 1, or 2 in which

said core is accompanied by at least one lamina made of a material chosen from a group consisting of woods, metals, ceramics, graphite fiber-resin composites and glass fiber-resin composites.

9. An improved soundboard as claimed in claim 8 in which

a pair of laminae are attached to different surfaces of said core.

10. An improved soundboard as claimed in claim 8 in which

said lamina is attached to said core as an intermediate layer.

11. An improved soundboard as claimed in claim 1 or 2 in which

said materials for said core is chosen from the group consisting of spruce, pine and cedar, graphite fiber-resin composites and glass fiber-resin composites.

2. An improved soundboard for musical instrurnents comprising fore and rear plates, and

a core interposed between and bonded to said fore and rear plates and made of a material with a shearing elastic modulus greater than that of said fore and rear plates and with a shearing loss tangent that is less than that of said fore and rear plates.

12. An improved soundboard as claimed in claim 2, in which

said shearing loss tangent of said material for said core is 20% or more less than that of said material for said fore and rear plates.