1. Field of the Invention
The present invention relates to a board for a stringed instrument, a method of manufacturing a board for a stringed instrument, and a stringed instrument.
Priority is claimed on Japanese Patent Application No. 2013-219355, filed on Oct. 22, 2013, the content of which is incorporated herein by reference.
2. Description of Related Art
Front and back plates of a violin have partially different thicknesses so as to obtain satisfactory acoustic characteristics and have a unique camber shape of being gently curved to be convex toward a front or back surface side thereof. Front and back plates used in a viola, a cello, and a double bass belonging to the violin family also have a camber shape having partially different thicknesses as in the case of a violin.
In the related art, during the manufacture of front and back plates of the violin family, a solid wooden block is cut or carved to be formed in a camber shape having partially different thicknesses. However, when a solid wooden block is cut to manufacture front and back plates, there are problems in that time and labor are required due to a significantly large number of cutting processes, and the material yield is extremely low at about 10%.
Recently, as front and back plates of the violin family, plates in which a camber shape having partially different thicknesses is formed by press-bending a board having a smaller thickness than a wooden block to partially compress and curve the board have been manufactured (refer to p. 203, “VIOLIN, Instrument Encyclopedia”, published by Tokyo Ongaku-sha).
In addition, front and back plates of the violin family can also be manufactured by laminating a plurality of veneers adhered to each other by an adhesive to obtain laminated wood and bending the laminated wood to be gently curved.
In the front and back plates, since a camber shape is formed by bending, the number of cutting processes for forming the camber shape can be reduced. Accordingly, these front and back plates can be more efficiently manufactured as compared to the plates manufactured by cutting a wooden block, and the material yield is also improved.
However, in the front and back plates formed by press-bending a board, the thicknesses thereof are made to be partially different and a predetermined thickness distribution is formed by partially compressing the board. Therefore, the wood density in the compressed portion increases, and a variation in density is significantly large in the front and back plates. Even if front and back plates of the violin family have a unique camber shape, when a variation in density is large, a vibration during playing is different from the unique vibration of the violin family. Therefore, in a stringed instrument including a front plate and/or a back plate formed by press-bending, satisfactory acoustic characteristics may not be obtained.
In addition, in the front and back plates formed by press-bending, after the manufacture, a thickness distribution and a camber shape thereof are likely to be changed by a restoring force of compressed wood. Therefore, when a stringed instrument including the front and back plates formed by press-bending is used for a long period of time, acoustic characteristics may deteriorate, or there may be a damage caused by deformation of the front plate and/or the back plate.
On the other hand, in the front and back plates in which a camber shape is formed by bending laminated wood, the laminated wood is not partially compressed during the manufacture, and thus a variation in density is small. Accordingly, the above-described problems caused by the density in the front and back plates do not occur.
However, these front and back plates are uniform in thickness. Therefore, in a stringed instrument including these front and back plates, a vibration of the front and back plates during playing is different from the unique vibration of the violin family, and satisfactory acoustic characteristics may not be obtained.
In addition, there may be a case where a camber shape having partially different thicknesses is formed by press-bending laminated wood. However, in this case, since the laminated wood is partially compressed by press-bending, a variation in density is large in the front and back plates.
In addition, there may be a case where a camber shape having partially different thicknesses is formed by cutting laminated wood before or after bending the laminated wood. However, when the laminated wood is cut, a laminated cross-section is exposed to the surface, and a good appearance cannot be obtained.
The present invention has been made in consideration of the above-described circumstances, and an object thereof is to provide a board for a stringed instrument which can be efficiently manufactured, has high material yield, has a small variation in density, has partially different thicknesses, has a shape of being curved to be convex toward one surface side thereof, and forms a front plate or a back plate having superior shape stability and acoustic characteristics.
In addition, another object of the present invention is to provide a stringed instrument which is not likely to be damaged by deformation of a front plate and/or a back plate and is superior in acoustic quality, the stringed instrument including a front plate and/or a back plate made of a board for a stringed instrument which can be efficiently manufactured and has high material yield.
According to an aspect of the present invention, there is provided a board for a stringed instrument which forms a front plate or a back plate of a stringed instrument, the board including: a veneer that includes a concave portion for partially reducing the thickness of the veneer, in which the veneer is curved to be convex toward one surface side.
According to another aspect of the present invention, there is provided a method of manufacturing a board for a stringed instrument which forms a front plate or a back plate of a stringed instrument, the method including: a process of forming a concave portion on a veneer so as to partially reduce the thickness of the veneer; and a process of curving the veneer to be convex toward one surface side.
According to still another aspect of the present invention, there is provided a stringed instrument including the board for a stringed instrument according to the aspect of the present invention.
In the board for a stringed instrument according to the aspect of the present invention which forms a front plate and a back plate of a stringed instrument, the veneer that includes a concave portion for partially reducing the thickness of the veneer is curved to be convex toward one surface side. Accordingly, in the board for a stringed instrument according to the aspect of the present invention, it is not necessary to partially compress the board in order for the board to have partially different thickness. Therefore, variation in the density of the board for a stringed instrument is small. Accordingly, when the board for a stringed instrument according to the aspect of the present invention is used as a front plate or a back plate, the unique vibration of the violin family is obtained during play, and the acoustic characteristics thereof are superior.
In addition, in the board for a stringed instrument according to the aspect of the present invention, partial compression of the board is not necessary, and thus a thickness distribution and a curved shape are not changed by a restoring force of compressed wood. Accordingly, the board for a stringed instrument according to the aspect of the present invention has superior shape stability as compared to front and back plates of the related art formed by press-bending.
In the board for a stringed instrument according to the aspect of the present invention, the veneer includes a concave portion for partially reducing the thickness of the veneer. In addition, the veneer is curved to be convex toward one surface side. Accordingly, the board for a stringed instrument according to the aspect of the present invention can be manufactured with a small number of cutting or carving processes as compared to the conventional case where the camber shape is formed by cutting or carving. As a result, the board for a stringed instrument according to the aspect of the present invention can be more efficiently manufactured as compared to the plates manufactured by cutting a wooden block, and the material yield is also improved.
The method of manufacturing a board for a stringed instrument according to the aspect of the present invention includes the process of curving the veneer, which includes the concave portion for partially reducing the thickness of the veneer, to be convex toward one surface side. Accordingly, a board for a stringed instrument having partially different thicknesses and a small variation in density can be obtained without partially compressing wood. In addition, in the method of manufacturing a board for a stringed instrument according to the aspect of the present invention, a board for a stringed instrument can be efficiently manufactured with a small number of cutting processes as compared to a case where deformation formed by the veneer being curved is formed by cutting.
In addition, the stringed instrument according to the aspect of the present invention includes the board for a stringed instrument according to the aspect of the present invention. As a result, the acoustic qualities are superior. In addition, the stringed instrument according to the aspect of the present invention is not likely to be damaged by deformation of a front plate and a back plate and thus can be used for a long period of time.
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
In this embodiment, a front plate of a violin will be described as an example of a board for a stringed instrument according to the present invention.
As shown in
The laminated plate 11 includes a veneer 3 including a concave portion 34. A front surface plate 1 is laminated on a front surface 3a of the veneer 3 by an adhesive 4. In addition, a back surface plate 2 is laminated on a back surface 3b of the veneer 3 by the adhesive 4. The front surface plate 1 and the back surface plate 2 are made of a veneer having a uniform thickness and function as a decorative sheet which covers the front surface 3a or the back surface 3b of the veneer 3. In addition, the front surface plate 1 and the back surface plate 2 also have a function of reinforcing the veneer 3 along with the adhesive 4 to prevent deformation of the veneer 3.
In the front plate 10 shown in
On the back surface 3b (bottom surface of the veneer 3 in
Regarding the thickness of the veneer 3, as shown in
The thickness distribution of the veneer is determined according to performance required for a front plate or a back plate of a violin and is not limited to the thickness distribution of the veneer 3 shown in
Examples of the materials of the veneer 3, the front surface plate 1, and the back surface plate 2 include spruce, maple, pine, Japanese cedar, birch, beech, or lauan. Among these, spruce is preferably used because a high function of the front plate 10 as a vibrating plate can be obtained.
All the materials of the veneer 3, the front surface plate 1, and the back surface plate 2 may be the same, or all or a part of the materials may be different. In the embodiment, all of the veneer 3, the front surface plate 1, and the back surface plate 2 are made of spruce. As a result, a higher function as the front plate 10 can be obtained, and the acoustic quality of a violin using this front plate 10 can be further improved.
In the front plate 10 according to the embodiment, the front surface plate 1 is made of straight-grained spruce, and a fiber direction thereof is aligned to a length direction of the front plate 10 in plan view. As a result, a better appearance can be obtained. In addition, the front surface plate 1 of the front plate 10 has a continuous plane which is integrated by aligning end surfaces of two veneers to face each other at a center portion in a length direction of the front plate 10 and joining the end surfaces to each other. As a result, a good appearance having a joint at the center portion in the length direction of the front plate 10 is obtained.
In the front plate 10 shown in
The thickness of the front surface plate 1 is more preferably 0.3 mm or more. In this case, a cutting stock of the front surface of the laminated plate 11 can be sufficiently secured. Accordingly, even if the thickness distribution of the front plate 10 is finely adjusted or convex and concave portions present on the front surface of the front plate 10 are removed by cutting the front surface of the laminated plate 11 using, for example, a scraper, the front surface of the veneer 3 can be prevented from being exposed. In addition, the thickness of the front surface plate 1 is preferably 0.3 mm or more because a step which is formed by the concave portion 34 formed on the veneer 3 can be prevented from being taken over to front surface of the front plate 10 to form a convex portion.
As the adhesive 4, one not containing a solvent such as water or an organic solvent is preferably used. Specifically, examples of the adhesive 4 not containing a solvent include a urethane-based adhesive, an epoxy-based adhesive, and a phenol-based adhesive. By using the adhesive not containing a solvent as the adhesive 4, deformation of the front surface plate 1 and/or the back surface plate 2 caused by infiltration of an adhesive 4 into the front surface plate 1 and/or the back surface plate 2 can be prevented during the manufacture of the laminated plate 11. Accordingly, the thickness distribution of the laminated plate 11 can be controlled with higher accuracy.
In this embodiment, a method of manufacturing the front plate of the violin shown in
In order to manufacture the front plate 10 shown in
The veneer 3 shown in
On the bottom surface of the concave portion 34, as shown in
When the front surface plate 1, the veneer 3, and the back surface plate 2 are laminated to form the laminate 10a shown
In addition, a part of the fiber directions of the front surface plate 1, the veneer 3, and the back surface plate 2, for example, a fiber direction of the back surface plate 2 may be aligned to the width direction of the front plate 10 in consideration of the strength and shape stability of the front plate 10.
As the adhesive 4, as described above, an adhesive not containing a solvent such as a urethane-based adhesive, an epoxy-based adhesive, or a phenol-based adhesive is preferably used. As the adhesive 4, a thermal adhesive sheet may also be used.
Next, the laminate 10a shown in
It is preferable that the bending process be performed under a condition where a compressive stress is not applied to the front surface plate 1, the veneer 3, and the back surface plate 2. Accordingly, the laminated plate 11 has a uniform density similar to the intrinsic density of wood which forms the front surface plate 1, the veneer 3, and the back surface plate 2. As a result, deformation of the manufactured front plate 10 can be further suppressed, and the front plate 10 can obtain superior acoustic characteristics intrinsic to wood.
In addition, a temperature condition of the bending process is not particularly limited and can be appropriately determined according to the kind of the adhesive 4 to be used. For example, when a thermoset adhesive is used as the adhesive 4, it is preferable that the adhesive 4 be cured during the bending process by performing the bending process while performing a heat treatment to a predetermined temperature.
Next, the curved laminated plate 11 is cut using, for example, a saw along a visible outline (not shown) of the front plate 10 which is positioned outside the contour of the concave portion 34 of the veneer 3 in a plan view, thereby obtaining the front plate 10 having a predetermined external shape shown in
Next, optionally, a finishing process may be performed in which the thickness distribution of the front plate 10 is finely adjusted or convex and concave portions present on the front surface of the front plate 10 are removed by cutting the front surface of the laminated plate 11 using, for example, a scraper.
Through the above-described processes, the front plate 10 shown in
In addition, in the front plate 10 shown in
In the front plate 10 shown in
Further, in the front plate 10 shown in
In addition, in the front plate 10 shown in
In the front plate 10 shown in
The method of manufacturing the front plate 10 shown in
In this embodiment, a back plate of a violin will be described as an example of a board for a stringed instrument according to the present invention.
The back plate of the violin according to the embodiment is different from the front plate 10 according to the first embodiment shown in
In the back plate according to the embodiment, it is more preferable that all of the front surface plate, the back surface plate, and the veneer be made of maple. By allowing all the front surface plate, the back surface plate, and the veneer to be made of maple, a higher function as the back plate can be obtained, and the acoustic quality of a violin using this back plate can be further improved. In addition, in the back plate according to the embodiment, a better appearance can be obtained by using maple having grain as the materials of the veneers which form the front surface plate.
The back plate of the violin according to the embodiment can be manufactured with the same method as the front plate 10 according to the above-described first embodiment.
In addition, with the back plate according to the embodiment, the same effects as the front plate 10 according to the above-described first embodiment can be obtained. That is, the back plate according to the embodiment can be efficiently manufactured and has high material yield. Accordingly, the back plate according to the embodiment has a small variation in density, has partially different thicknesses, has a shape of being curved to be convex toward one surface side, superior shape stability, a good appearance, and superior acoustic characteristics.
In this embodiment, a violin will be described as an example of a stringed instrument according to the present invention.
In
In the violin 50 shown in
In the violin 50 shown in
The violin 50 can be manufactured with a well-known method of the related art by using the front plate according to the first embodiment as the front plate 10 and using the back plate according to the second embodiment as the back plate 20.
Specifically, for example, the back plate 20 and the side plate 30 are bonded to each other using an adhesive such as glue. Next, the side plate 30 and the front plate 10 are bonded to each other using an adhesive such as glue to form a body. Next, the neck 40 is attached to the body, and the front surface is coated with varnish. Next, a fingerboard is attached, and a sound post is installed. Next, a bridge is installed, and strings are tensed.
Through the above-described processes, the violin 50 shown in
The violin 50 can be manufactured by using the front plate according to the first embodiment as the front plate 10 and using the back plate according to the second embodiment as the back plate 20, and thus has a good appearance and is superior in acoustic qualities. In addition, the violin 50 is not likely to be damaged by deformation of the front plate 10 and the back plate 20 and thus can be used for a long period of time.
The stringed instrument and the board for a stringed instrument according to the present invention are not limited to the above-described embodiments.
For example, the stringed instrument according to the present invention is not limited to a violin and may be a viola, a cello, or a double base belonging to the violin family. In addition, the present invention can also be applied to a stringed instrument, such as a guitar or the like, including a front plate and/or a back plate having a camber shape which is curved to be convex toward one surface side.
In the above-described example of the embodiments, the bottom surfaces having different depths are formed in three steps as the bottom surface of the concave portion of the veneer. However, the bottom surface may be a continuous curved shape. In addition, the number of depth steps of bottom surfaces having different depths is not particularly limited may be two, three as in the case of the above-described embodiments, or four or more.
In addition, in the above-described embodiment, a step is formed at the boundary portion between the bottom surfaces having different depths. However, an inclined surface for alleviating the step may be formed at the boundary portion between the bottom surfaces.
In addition, in the front plate 10 shown in
In addition, in the above-described example, the front plate 10 shown in
When a board for a stringed instrument is a front plate not including a front surface plate, it is preferable that the veneer be made of straight-grained spruce in order to obtain a better appearance and high acoustic quality. When a board for a stringed instrument is a back plate not including a front surface plate, it is preferable that the veneer be made of maple having grain in order to obtain a better appearance and high acoustic quality.
In addition, when a front surface plate is not provided, the veneer may have a continuous plane which is integrated by aligning end surfaces of two veneers to face each other at a center portion in a length direction of a front plate or a back plate and joining the end surfaces to each other.
While preferred embodiments of the invention have been described and shown above, it should be understood that these are exemplary of the invention and are not to be considered as limiting. Additions, omissions, substitutions, and other modifications can be made without departing from the spirit or scope of the present invention. Accordingly, the invention is not to be considered as being limited by the foregoing description, and is only limited by the scope of the appended claims.
Number | Date | Country | Kind |
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2013-219355 | Oct 2013 | JP | national |