JP2017173585A - Shell for membranophone - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a shell for a membranophone capable of reducing weight and improving hardness, and also suppressing deterioration of woody sound quality characteristics.SOLUTION: A cylindrical shell for a membranophone formed by laminating a plurality of veneers includes a carbon fiber-reinforced plastic (CFRP) layer laminated on the entire surface or a part of at least one veneer. A carbon fiber comprising the CFRP layer is preferably oriented in one direction. The CFRP layer is preferably laminated on the entire areas of opposing faces of a pair of veneers whose grains are orthogonal to each other. The shell for the membranophone includes a pair of ring-shaped CFRP layers, and the pair of CFRP layers are preferably laminated along both end edges of the opposing faces of the pair of veneers whose grains are orthogonal to each other. The shell for the membranophone includes a plurality of belt-like CFRP layers, and the plurality of CFRP layers are preferably laminated in parallel so that they are laid between both end edges of the opposing faces of the pair of veneers whose grains are orthogonal to each other.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a membrane musical instrument shell.

  Membrane musical instruments having a cylindrical shell and a head membrane that closes the opening of the shell are widely used. This membrane musical instrument has a head membrane stretched so as to close the opening of the shell, and is configured to generate sound by vibrating (heading) the head membrane from the outside.

  This shell for membrane instruments is formed using various materials such as wood, metal, and resin (see Japanese Patent Laid-Open No. 8-248950). These membrane sound instrument shells are required to have various sound quality characteristics and strengths depending on the application, and for membrane sound instrument shells made of wood, such sound quality characteristics and strengths depend on the type and thickness of the wood. It is adjusted by controlling.

  Specifically, the strength of a shell for membrane musical instruments using wood is increased by using wood with high specific gravity or increasing the thickness. However, if wood with a high specific gravity is used or the thickness is increased, the shell for the membrane instrument becomes heavy and the handleability is reduced. In addition, it is conceivable to increase the strength by using a backer made of metal or synthetic resin together with wood. However, according to such a method, the shell for the membranous instrument becomes heavy and the woody sound characteristic is deteriorated.

JP-A-8-248950

  The present invention has been made based on such circumstances, and an object of the present invention is to provide a shell for a membrane musical instrument that can reduce weight and improve strength and suppress deterioration in woody sound characteristics. There is to do.

  In order to solve the above-mentioned problems, the present invention is a cylindrical membrane sound instrument shell in which a plurality of single plates are laminated, and is reinforced with carbon fiber laminated on the whole surface or a part of at least one single plate. This is a shell for a membranous musical instrument comprising a plastic (CFRP) layer.

  Since the CFRP layer is laminated on the entire surface or a part of at least one veneer, the strength of the membrane musical instrument shell can be increased. Since the membrane musical instrument shell is increased in strength by the CFRP layer, it is possible to suppress an increase in thickness, thereby reducing the weight. Moreover, since the said shell for membrane musical instruments raises an intensity | strength by a CFRP layer, the fall of a woody sound characteristic can be suppressed compared with the case where the backer made from a metal or a synthetic resin is used.

  The carbon fibers constituting the CFRP layer may be oriented in one direction. As described above, since the carbon fibers constituting the CFRP layer are oriented in one direction, anisotropy can be controlled, the strength in a desired direction can be effectively increased, and the wood sound It is possible to easily and reliably suppress deterioration of characteristics.

  The CFRP layer may be laminated on the entire opposing surfaces of a pair of single plates in which the wood is orthogonal. As described above, since the CFRP layer is laminated on the entire opposing surfaces of the pair of single plates in which the wood is orthogonal, it is possible to enhance the strength of the whole while suppressing the deterioration of the woody sound characteristics.

  The membrane musical instrument shell may include a pair of ring-shaped CFRP layers, and the pair of CFRP layers may be laminated along both end edges of the opposing surfaces of a pair of single plates in which the wood is orthogonal. Thus, by laminating a pair of CFRP layers along opposite edges of the opposing surfaces of a pair of single plates in which the wood is orthogonal, the circumferential strength of the membrane sound instrument shell is effectively increased. Can be increased. As a result, the roundness of the membrane musical instrument shell can be increased, and the sound quality can be improved. Moreover, when the CFRP layer does not exist in the central portion in the central axis direction of the membrane sound instrument shell, it is possible to more reliably suppress the deterioration of the woody sound characteristics.

  The membrane musical instrument shell includes a plurality of strip-like CFRP layers, and the plurality of CFRP layers are laminated in parallel so as to be bridged between the opposite end edges of a pair of single plates in which the wood is orthogonal. It is good to be. In this way, a plurality of strip-like CFRP layers are laminated in parallel so as to be bridged between the opposite ends of the opposing surfaces of a pair of single plates in which the wood is orthogonal, so that the center of the membrane musical instrument shell is centered. The strength in the axial direction can be effectively increased. In addition, a plurality of strip-like CFRP layers are stacked in parallel so as to be bridged between the opposite edges of the opposing surfaces of a pair of single plates, thereby reducing the existing area of the CFRP layer and more reliably lowering the woody sound characteristics. Can be suppressed.

  As described above, the membrane musical instrument shell according to the present invention can reduce the weight and improve the strength and suppress the deterioration of the woody sound characteristics.

It is a typical perspective view which shows the membrane musical instrument provided with the shell for membrane musical instruments which concerns on one Embodiment of this invention. FIG. 2 is a schematic plan view showing a membrane musical instrument shell of the membrane musical instrument of FIG. 1. It is a typical partial expanded sectional view which shows the shell for membrane sound musical instruments of FIG. It is a typical partial exploded perspective view which shows the unit plywood of the shell for membrane sound musical instruments of FIG. FIG. 5 is a schematic partial exploded perspective view showing a unit plywood different from the unit plywood of FIG. 4 of the membrane musical instrument shell of FIG. 2. It is a schematic diagram explaining the unit plywood formation process of the manufacturing method of the shell for membrane musical instruments of FIG. 2, Comprising: (a) is sectional drawing, (b) is a plane for demonstrating the grain direction of a 1st single board. FIG. It is a typical perspective view explaining the superimposition process of the manufacturing method of the shell for membrane musical instruments of FIG. It is a typical perspective view explaining the bonding process of the manufacturing method of the shell for membrane sound musical instruments of FIG. FIG. 6 is a schematic partial exploded perspective view showing a unit plywood according to a different form from the unit plywood of FIGS. 4 and 5. FIG. 10 is a schematic partial exploded perspective view showing a unit plywood according to a different form from the unit plywood of FIGS. 4, 5, and 9. It is a typical partial exploded perspective view which shows the unit plywood which concerns on a different form from the unit plywood of FIG.4, FIG.5, FIG.9 and FIG. It is a typical partial exploded perspective view which shows the unit plywood which concerns on the form different from the unit plywood of FIG.4, FIG.5, FIG.9-11. It is a typical partial exploded perspective view which shows the unit plywood which concerns on a different form from the unit plywood of FIG.4, FIG.5, FIG.9-12. It is a typical partial exploded perspective view which shows the unit plywood which concerns on a different form from the unit plywood of FIG.4, FIG.5, FIG.9-13. It is a typical partial exploded perspective view which shows the shell for membrane sound musical instruments which concerns on other embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings as appropriate.

[Membrane instrument]
FIG. 1 shows a membrane musical instrument including a membrane musical instrument shell 1 according to an embodiment of the present invention. The membrane musical instrument of FIG. 1 includes the membrane musical instrument shell 1 according to the present invention and a pair of head membranes 2 that block a pair of openings of the membrane musical instrument shell 1. The pair of head membranes 2 are stretched so as to close the pair of openings of the membrane sound instrument shell 1. The material of the pair of head films 2 is not particularly limited, and examples thereof include synthetic resin and leather.

<Shell for membrane instrument>
The membrane musical instrument shell 1 is formed in a cylindrical shape as shown in FIGS. 1 and 2. As shown in FIG. 3, the membrane musical instrument shell 1 is a laminated body in which a plurality of first single plates 11a and a plurality of second single plates 11b are stacked. Further, as shown in FIG. 3, the membrane sound instrument shell 1 includes a plurality of carbon fiber reinforced plastic (CFRP) layers 12 a laminated on the first veneer 11 a and the second veneer 11 b.

  The first single plate 11a and the second single plate 11b are orthogonal to each other. Specifically, the grain of the first veneer 11a is oriented in the circumferential direction, and the grain of the second veneer 11b is oriented in the central axis direction. The carbon fibers constituting the CFRP layer 12a are oriented in the circumferential direction.

  As shown in FIGS. 2 and 3, the membrane sound instrument shell 1 is formed by laminating a plurality of unit plywoods (first unit plywood 13 and second unit plywood 14). Moreover, the 1st unit plywood 13 and the 2nd unit plywood 14 are the 1st veneer 11a and the 2nd veneer 11b to which a wood grain orthogonally crosses respectively, and the whole surface of the opposing surface of the 1st veneer 11a and the 2nd veneer 11b. The CFRP layer 12a is laminated. Specifically, in the first unit plywood 13, a first single plate 11a, a CFRP layer 12a, and a second single plate 11b are laminated in this order from the outside in the radial direction. The plate 11b, the CFRP layer 12a, and the first single plate 11a are laminated in this order from the outside in the radial direction. The membrane musical instrument shell 1 is a laminate of three unit plywoods, and a first unit plywood 13, a first unit plywood 13 and a second unit plywood 14 are arranged in this order from the outside in the radial direction. The membrane musical instrument shell 1 has a plurality of layers other than a plurality of first single plates 11a, a plurality of second single plates 11b, a plurality of CFRP layers 12a, and an adhesive layer (not shown) for bonding these layers. do not do.

  The material of the plurality of first single plates 11a and the plurality of second single plates 11b is not particularly limited. And wood such as beech. The plurality of first single plates 11a and the plurality of second single plates 11b may be made of the same material or different materials.

  The plurality of CFRP layers 12a are formed by impregnating a carbon fiber in a thermosetting resin such as an epoxy resin and curing a sheet-like prepreg obtained by semi-curing the thermosetting resin. ing. Each CFRP layer 12a may be formed from one prepreg, or may be formed from a laminate of a plurality of prepregs. In the present embodiment, the carbon fibers constituting each CFRP layer 12a are oriented in one direction. Therefore, when each CFRP layer 12a is formed from a plurality of prepregs, the carbon fibers of the plurality of prepregs forming each CFRP layer 12a are oriented in the same direction. The membrane musical instrument shell 1 can control anisotropy for each CFRP layer 12a because the carbon fibers constituting each CFRP layer 12a are oriented in one direction. It is possible to effectively increase the strength in the desired direction along the line, and to easily and reliably suppress the deterioration of the woody sound characteristics.

  The membrane musical instrument shell 1 has a substantially uniform thickness. The lower limit of the average thickness of the membrane sound instrument shell 1 is preferably 3 mm, and more preferably 5 mm. On the other hand, the upper limit of the average thickness of the membrane sound instrument shell 1 is preferably 15 mm, and more preferably 12 mm. If the average thickness of the membrane sound instrument shell 1 is less than the lower limit, the strength may be insufficient. Conversely, if the average thickness of the membrane musical instrument shell 1 exceeds the upper limit, the weight increases and the handling of the membrane musical instrument shell 1 may be reduced.

  As a minimum of average thickness of the 1st single plate 11a and the 2nd single plate 11b, 0.3 mm is preferred, 0.5 mm is more preferred, and 0.7 mm is still more preferred. On the other hand, the upper limit of the average thickness of the first single plate 11a and the second single plate 11b is preferably 2.5 mm, more preferably 2.0 mm, and even more preferably 1.5 mm. If the average thickness of the first veneer 11a and the second veneer 11b is less than the lower limit, the number of the first veneer 11a and the second veneer 11b in the membrane musical instrument shell 1 is increased. As the process becomes complicated, the amount of the adhesive that bonds the first veneer 11a and the second veneer 11b may increase and become unnecessarily heavy. Conversely, if the average thickness of the first veneer 11a and the second veneer 11b exceeds the upper limit, the first veneer 11a and the second veneer 11b are difficult to round into a cylindrical shape. There is a possibility that the manufacture of the shell 1 may be difficult. Moreover, when the average thickness of the 1st single board 11a and the 2nd single board 11b exceeds the said upper limit, when manufacturing the said shell 1 for membrane sound instruments, a special apparatus may be needed and manufacturing cost may increase. .

  As a minimum of average thickness of CFRP layer 12a, 0.02 mm is preferred and 0.05 mm is more preferred. On the other hand, the upper limit of the average thickness of the CFRP layer 12a is preferably 0.6 mm, and more preferably 0.2 mm. If the average thickness of the CFRP layer 12a is less than the lower limit, the strength improvement effect by the CFRP layer 12a may not be sufficiently obtained. If the average thickness of the CFRP layer 12a is less than the lower limit, it may be difficult to form the CFRP layer 12a. On the contrary, if the average thickness of the CFRP layer 12a exceeds the upper limit, the weight and thickness of the membrane sound instrument shell 1 may become unnecessarily large and the woody sound characteristics may be deteriorated.

  The first unit plywood 13 and the second unit plywood 14 are excellent in shape stability because the CFRP 12a layer is laminated between the first single plate 11a and the second single plate 11b in which the wood is orthogonal. That is, a force that tends to shrink in the circumferential direction is likely to act on the second single plate 11b in which the grain is oriented in the central axis direction, but the first single plate 11a and the CFRP layer 12a are hardly deformed in the circumferential direction. Therefore, by laminating the first single plate 11a and the CFRP layer 12a on the second single plate 11b, it becomes difficult for the second unit plywood 14 to shrink in the circumferential direction, and the shape stability is improved.

  The membrane musical instrument shell 1 has the CFRP layer 12a laminated on the entire opposing surfaces of the first veneer 11a and the second veneer 11b where the woods are orthogonal to each other. However, it is possible to increase the overall strength. In particular, the membrane sound instrument shell 1 can easily maintain the woody sound characteristic because the carbon fibers constituting the CFRP layer 12a are oriented in one direction. Furthermore, since the CFRP layer 12a is disposed between the first single plate 11a and the second single plate 11b, the CFRP layer 12a is not visually recognized from the outside. Therefore, the membrane sound instrument shell 1 can prevent the deterioration of the appearance due to the CFRP layer 12a.

  As shown in FIG. 4, in the first unit plywood 13, the first single plate 11a constitutes the radially outer surface, the second single plate 11b constitutes the radially inner surface, and the first single plate 11a and the first single plate 13a. A CFRP layer 12a is disposed between the two single plates 11b (note that the arrows in FIG. 4 indicate the orientation of the wood and the carbon fibers (the same applies to the arrows in the other figures)). The first unit plywood 13 does not have any layers other than the first veneer 11a, the second veneer 11b, the CFRP layer 12a, and an adhesive layer (not shown) that bonds these layers. In the first unit plywood 13, the grain of the first veneer 11a constituting the radially outer surface and the carbon fibers constituting the CFRP layer 12a laminated on the inner peripheral surface of the first veneer 11a are oriented in the circumferential direction. Therefore, the strength against the force applied from the outside in the radial direction is high. Therefore, the membrane sound instrument shell 1 is arranged so that the first unit plywood 13 constitutes the radially outer side surface, thereby suppressing deformation due to the force applied from the radially outer side and improving the roundness. The sound quality characteristics can be further improved.

  As shown in FIG. 5, in the second unit plywood 14, the second single plate 11 b constitutes the radially outer side surface, the first single plate 11 a constitutes the radially inner side surface, and the first single plate 11 a and the first unit plate 14. A CFRP layer 12a is disposed between the two single plates 11b. The second unit plywood 14 has no layers other than the first veneer 11a, the second veneer 11b, the CFRP layer 12a, and an adhesive layer (not shown) that bonds these layers. In the second unit plywood 14, the grain of the first single plate 11a constituting the radially inner side and the carbon fibers constituting the CFRP layer 12a laminated on the outer peripheral surface of the first single plate 11a are oriented in the circumferential direction. Therefore, the strength against the force applied from the radially inner side is high. For this reason, the membrane musical instrument shell 1 is arranged so that the second unit plywood 14 constitutes the radially inner side surface, thereby suppressing deformation due to the force applied from the radially inner side and further improving the roundness. Sound quality characteristics can be improved.

<Manufacturing method>
Next, with reference to FIGS. 6-8, the manufacturing method of the said shell 1 for membrane sound musical instruments is demonstrated. The manufacturing method of the membrane musical instrument shell includes a step of forming unit plywood (unit plywood forming step), a step of superimposing a plurality of unit plywood (superimposing step), and a plurality of unit plywood stacked. A process (bonding process).

(Unit plywood forming process)
In the unit plywood forming step, the flat plate-like first unit plywood 13 and second unit plywood 14 in which the CFRP layer 12a is laminated between the first veneer 11a and the second veneer 11b where the wood is orthogonal are formed. The formation procedure of the first unit plywood 13 and the second unit plywood 14 is the same except that the wood direction of each single plate is different. Therefore, only the formation procedure of the first unit plywood 13 will be described below with reference to FIG.

  In the unit plywood forming step, first, an adhesive is applied to the first veneer 11a, and a prepreg for forming the CFRP layer 12a is laminated on the adhesive application surface. Subsequently, in the unit plywood forming step, an adhesive is applied to the outer surface of the prepreg (the surface opposite to the laminated surface with the first single plate 11a), and the second single plate 11b is applied to the application surface of the adhesive. Laminate (see FIG. 6A). In the unit plywood forming step, the wood direction of the first veneer 11a and the orientation direction of the carbon fibers of the prepreg are parallel, and the wood direction of the first veneer 11a and the wood direction of the second veneer 11b The first veneer 11a, the prepreg, and the second veneer 11b are bonded together so as to be orthogonal to each other. As shown in FIG. 6B, the first unit plywood 13 formed in this unit plywood forming step may have a parallelogram shape in plan view in which the grain of the first single plate 11a is parallel to the longitudinal direction. preferable. The adhesive used in the unit plywood forming step is preferably the same resin adhesive as the resin used for the CFRP layer 12a. For example, an epoxy adhesive can be used.

As a minimum of the application amount of the adhesive, 50 g / m ² is preferable, and 60 g / m ² is more preferable. On the other hand, as an upper limit of the application amount of the adhesive, 270 g / m ² is preferable, and 200 g / m ² is more preferable. If the application amount of the adhesive is less than the lower limit, the adhesive strength of each layer may be insufficient. On the contrary, when the application amount of the adhesive exceeds the upper limit, the carbon fibers contained in the CFRP layer 12a may flow out. Moreover, when the application amount of the adhesive exceeds the upper limit, the weight of the membrane sound instrument shell 1 becomes unnecessarily large, and the sound quality may be deteriorated.

(Overlay process)
The superposition process is performed using the outer mold 21 shown in FIG. The outer mold | type 21 is formed in the cylindrical shape which has the hollow part 21a inside, and the internal peripheral surface which demarcates the hollow part 21a comprises the molding surface. In the superimposing step, first, the first unit plywood 13 disposed on the outermost radial direction in the membrane sound instrument shell 1 is rolled into a cylindrical shape so that the grain of the first single plate 11a is oriented in the circumferential direction. In addition, it is inserted into the hollow portion 21 a of the outer mold 21.

Next, in the superposition process, an adhesive is applied to the inner peripheral surface of the inserted first unit plywood 13. Examples of the adhesive include urea-based adhesives, vinyl acetate-based adhesives, vinyl urethane-based adhesives, and melamine-based adhesives. As a minimum of the application amount of this adhesive, 80 g / m ² is preferable, and 100 g / m ² is more preferable. In contrast, the upper limit of the coating weight of the adhesive, preferably ^{400g / m 2, 350g / m} 2 is more preferable. If the application amount of the adhesive is less than the lower limit, the adhesive force between the first unit plywood 13 and the other unit plywood stacked on the first unit plywood 13 may be insufficient. On the contrary, when the application amount of the adhesive exceeds the upper limit, the weight of the membrane sound instrument shell 1 becomes unnecessarily large and the sound quality may be deteriorated. In the superposition step, it is preferable to apply an adhesive to the inner peripheral surface of the first unit plywood 13 after the first unit plywood 13 is inserted into the hollow portion 21a of the outer mold 21. An adhesive may be applied before 13 is inserted into the hollow portion 21 a of the outer mold 21.

  Subsequently, in the superimposing step, another unit plywood is prepared, and an adhesive is applied to the laminated surface of the unit plywood with the first unit plywood 13 inserted into the hollow portion 21a of the outer mold 21. As this adhesive, an adhesive similar to the adhesive applied to the first unit plywood 13 inserted into the hollow portion 21 of the outer mold 21 can be used. Further, the application amount of the adhesive may be the same as the application amount of the adhesive applied to the inner peripheral surface of the first unit plywood 13 described above.

  Further, in the superimposing step, the other unit plywood is rounded into a cylindrical shape so that the adhesive application surface is on the outside, and then superimposed on the inner peripheral surface of the first unit plywood 13 inserted into the hollow portion 21a. Match.

  In the superimposing step, the unit plywood thus rounded into a cylindrical shape is sequentially superimposed on the inner peripheral surface side of the outer mold 21. However, in this superposition process, no adhesive is applied to the inner peripheral surface of the unit plywood constituting the innermost surface. In the method for manufacturing the membrane musical instrument shell, the overall thickness of the membrane musical instrument shell 1 is adjusted to a desired thickness by this superposition process. In the method for manufacturing the membrane sound instrument shell, each unit plywood can be easily and surely overlapped on the inner peripheral surface side of the outer mold 21 by adjusting each unit plywood to a thickness that can be relatively easily rounded. .

(Lamination process)
The bonding step is performed using an inner mold 22 shown in FIG. The inner mold 22 includes a columnar or cylindrical core portion 23, a pair of disk-shaped flange portions 24 connected radially outward from both axial ends of the core portion 23, and the pair of flange portions 24. And a cylindrical coating 25 formed continuously from an outer peripheral edge and formed of an elastic material such as rubber. The inner mold 22 has an air chamber 26 defined by a core portion 23, a pair of flange portions 24 and a coating 25. The air chamber 26 is connected to an air supply source by a pipe (not shown). The inner mold 22 is configured such that the coating film 25 expands radially outward by supplying compressed air from an air supply source to the air chamber 26.

  In the bonding step, first, the inner die 22 is inserted into the inner peripheral surface side of the plurality of unit plywood (first unit plywood 13 and second unit plywood 14) overlapped in the overlapping step, and the outer die 21 and the inner die are inserted. A plurality of unit plywoods are sandwiched between the molds 22. Next, in the bonding step, a heater (not shown) is attached to the outer periphery of the outer mold 21, and a plurality of unit plywoods are heated together with the outer mold 21 while supplying compressed air to the air chamber 26 of the inner mold 22. 25 is inflated. By the expansion of the coating 25, the plurality of unit plywoods are evenly pressed against the inner peripheral surface of the outer mold 21, and the plurality of unit plywoods are processed into shapes corresponding to the inner peripheral surface of the outer mold 21 and the outer peripheral surface of the inner mold 22. Is done. At the same time, the adhesive applied to the overlapping surfaces of the plurality of unit plywoods is cured by the heat from the heater. Thus, the membrane sound instrument shell 1 is formed in a desired shape. The pressing pressure in the bonding step can be, for example, 0.1 MPa or more and 1 MPa or less. Moreover, as said heating temperature, it can be set as 70 to 120 degreeC, for example. Furthermore, the heating time can be, for example, 10 minutes or more and 100 minutes or less.

  In addition, the manufacturing method of the said shell for membrane instruments may further comprise the process (cutting process) which cut | disconnects the part which protruded the both sides of the center axis direction of several unit plywood after the said bonding process. Moreover, the manufacturing method of the shell for membrane sound musical instrument may further include a step of painting the outer peripheral surface and / or the inner peripheral surface (painting step) after the bonding step.

<Advantages>
Since the CFRP layer 12a is laminated on the entire surface of the plurality of first single plates 11a and the plurality of second single plates 11b, the strength of the membrane sound instrument shell 1 can be increased by the CFRP layer 12a. Since the membrane musical instrument shell 1 is increased in strength by the CFRP layer 12a, it is possible to suppress an increase in thickness, thereby reducing the weight. Moreover, since the said shell 1 for membrane sound instruments raises an intensity | strength by the CFRP layer 12a, the fall of a woody sound characteristic can be suppressed compared with the case where the backer made from a metal or a synthetic resin is used.

  Since the membrane sound instrument shell 1 is increased in strength by the CFRP layer 12a, the attenuation rate can be kept low, and a sound with good sound can be easily produced at a high volume. Further, in the shell for musical instrument 1, the first unit plywood 13 and the second unit plywood 14 each include a CFRP layer 12a, and the strength is obtained by using the first unit plywood 13 and the second unit plywood 14. Since it can improve, the special process for an intensity | strength improvement is not required. Therefore, the strength of the membrane musical instrument shell can be easily and reliably improved.

  The membrane sound instrument shell manufacturing method can easily and reliably manufacture the membrane sound instrument shell 1 capable of reducing the weight and improving the strength and suppressing the deterioration of the woody sound characteristics.

<Unit plywood>
Next, referring to FIGS. 9 to 14, unit plywood used for the membrane musical instrument shell, which is different from the first unit plywood 13 and the second unit plywood 14 described above, is used. explain.

(Third unit plywood)
The third unit plywood 31 of FIG. 9 is a CFRP layer that is laminated on the entire surface of the first veneer 11a and the second veneer 11b, and the opposing surfaces of the first veneer 11a and the second veneer 11b. 12b. The third unit plywood 31 has no layers other than the first veneer 11a, the second veneer 11b, the CFRP layer 12b, and an adhesive layer (not shown) that bonds these layers. The third unit plywood 31 is configured in the same manner as the first unit plywood 13 in FIG. 4 except that the carbon fibers constituting the CFRP layer 12b are oriented in the central axis direction. The third unit plywood 31 has high strength in the central axis direction because the carbon fibers constituting the CFRP layer 12b are oriented in the central axis direction. Moreover, since the grain direction of the 1st single board 11a which comprises the radial direction outer side surface is orientating the circumferential direction in the 3rd unit plywood 31, the intensity | strength with respect to the force applied from a radial direction outer side is high. Therefore, the third unit plywood 31 can suppress deformation caused by the force applied from the outside in the radial direction and can increase the strength with respect to the central axis direction. Suitable for being arranged to constitute.

(Fourth unit plywood)
The fourth unit plywood 32 of FIG. 10 is a CFRP layer that is laminated on the entire surface of the first veneer 11a and the second veneer 11b, and the first veneer 11a and the second veneer 11b that are orthogonal to each other. 12c. The fourth unit plywood 32 does not have any layers other than the first veneer 11a, the second veneer 11b, the CFRP layer 12c, and an adhesive layer (not shown) that bonds these layers. In the fourth unit plywood 32, the orientation direction of the carbon fibers constituting the CFRP layer 12c is inclined with respect to the central axis. Specifically, the orientation direction of the carbon fibers constituting the CFRP layer 12c is inclined 45 ° with respect to the central axis. The fourth unit plywood 32 is configured in the same manner as the first unit plywood 13 of FIG. 4 except that the orientation direction of the carbon fibers constituting the CFRP layer 12c is inclined by 45 ° with respect to the central axis. In the fourth unit plywood 32, since the orientation direction of the carbon fibers constituting the CFRP layer 12c is inclined by 45 ° with respect to the central axis, the strength in the central axis direction and the circumferential direction can be increased substantially uniformly. Further, the fourth unit plywood 32 has a high strength against a force applied from the outside in the radial direction because the grain direction of the first single plate 11a constituting the radially outer side surface is oriented in the circumferential direction. Therefore, the fourth unit plywood 32 can suppress deformation caused by the force applied from the outside in the radial direction and can increase the strength in the central axis direction and the circumferential direction substantially uniformly. Suitable to be arranged to constitute the outer surface.

(Fifth unit plywood)
The fifth unit plywood 33 in FIG. 11 is a pair of first and second single plates 11a and 11b, and the first single plate 11a and the second single plate 11b, which are orthogonal to each other. The ring-shaped CFRP layer 12d is provided. The fifth unit plywood 33 does not have any layers other than the first veneer 11a, the second veneer 11b, the pair of CFRP layers 12d, and an adhesive layer (not shown) that bonds these layers. The carbon fibers constituting the pair of CFRP layers 12d are oriented in the circumferential direction. The pair of CFRP layers 12d are laminated along both end edges of the opposing surfaces of the first single plate 11a and the second single plate 11b (ends on both sides in the central axis direction of the membrane musical instrument shell). That is, in the fifth unit plywood 33, only the both end edges of the first single plate 11a and the second single plate 11b are laminated via the pair of CFRP layers 12d, and the other portions than the both end edges are the first single plate 11a. And the 2nd single plate 11b is laminated | stacked directly.

  The average thickness of the pair of CFRP layers 12d can be the same as the average thickness of the CFRP layer 12a of the first unit plywood 13 described above. Since the fifth unit plywood 33 has a relatively small average thickness of the pair of CFRP layers 12d, even if the CFRP layers 12d are laminated only on the both ends of the first single plate 11a and the second single plate 11b, Can be prevented from becoming too thick compared to other portions. Therefore, even when the fifth unit plywood 33 is used, the appearance of the membrane musical instrument shell can be prevented from deteriorating in appearance. Further, since the fifth unit plywood 33 has a relatively small average thickness of the pair of CFRP layers 12d, the first unit plate 11a and the second unit plate 11b are directly stacked without the pair of CFRP layers 12d. Adhesive strength can be maintained sufficiently.

  The lower limit of the average width (average length in the central axis direction) of the pair of CFRP layers 12d is preferably 5 mm, and more preferably 10 mm. On the other hand, the upper limit of the average width of the pair of CFRP layers 12d is preferably 50 mm, and more preferably 30 mm. If the average width of the pair of CFRP layers 12d is less than the lower limit, the strength improvement effect may not be sufficiently obtained. On the other hand, if the average width of the pair of CFRP layers 12d exceeds the upper limit, the existing area of the CFRP layer 12d becomes too large, and it may be difficult to easily and reliably suppress the deterioration of the woody sound characteristics.

  When the fifth unit plywood 33 is used, the membrane sound instrument shell is used together with another unit plywood in which a CFRP layer is laminated on the entire surface of the first veneer 11a and the second veneer 11b. The fifth unit plywood 33 can increase the partial strength while increasing the overall strength by the unit plywood. On the other hand, the shell for a membranous instrument is configured by using, for example, only a plurality of fifth unit plywoods 33 or using only one or a plurality of fifth unit plywoods 33 and only one or a plurality of single plates. It is easy to prevent the deterioration of the woody sound characteristics easily and surely.

  The membrane musical instrument shell using the fifth unit plywood 33 is formed by laminating a pair of CFRP layers 12d along both end edges of the opposing surfaces of the first single plate 11a and the second single plate 11b. The strength in the circumferential direction can be effectively increased. Particularly, in the membrane musical instrument shell using the fifth unit plywood 33, since the carbon fibers constituting the pair of CFRP layers 12d are oriented in the circumferential direction, it is easy to sufficiently increase the strength in the circumferential direction. Thereby, the said shell for membrane sound musical instruments using this 5th unit plywood 33 can raise roundness, and can improve a sound quality characteristic. Further, since the carbon fibers constituting the pair of CFRP layers 12d are oriented in the circumferential direction, the pair of CFRP layers 12d have anisotropy and can suppress a decrease in woody sound characteristics. Further, in the membrane musical instrument shell using the fifth unit plywood 33, a pair of ring-shaped CFRP layers 12d are laminated along both end edges of the opposing surfaces of the first single plate 11a and the second single plate 11b. In addition, since the CFRP layer 12d does not exist in the central portion of the membrane sound instrument shell in the central axis direction, it is possible to more reliably suppress the deterioration of the woody sound characteristics.

(6th unit plywood)
The sixth unit plywood 34 in FIG. 12 is a plurality of layers laminated on a part of the opposing surfaces of the first single plate 11a and the second single plate 11b, and the first single plate 11a and the second single plate 11b in which the wood is orthogonal. The strip-shaped CFRP layer 12e is provided. The sixth unit plywood 34 has no layers other than the first veneer 11a, the second veneer 11b, the plurality of CFRP layers 12e, and an adhesive layer (not shown) that bonds these layers. The carbon fibers constituting the plurality of CFRP layers 12e are oriented in the central axis direction. The plurality of CFRP layers 12e are arranged in parallel so as to be bridged between both end edges of the opposing surfaces of the first single plate 11a and the second single plate 11b (between both end edges in the central axis direction of the membrane musical instrument shell). Are stacked. The plurality of CFRP layers 12e have a longitudinal direction extending in parallel with the central axis direction. In the sixth unit plywood 34, only a plurality of portions parallel to the central axis direction of the first single plate 11a and the second single plate 11b are stacked via the CFRP layer 12e, and other than the stacked portions of the plurality of CFRP layers 12e. In this area, the first single plate 11a and the second single plate 11b are directly laminated.

  The average thickness of the plurality of CFRP layers 12e can be the same as the average thickness of the CFRP layers 12a of the first unit plywood 13 described above. Since the sixth unit plywood 34 has a relatively small average thickness of the plurality of CFRP layers 12e, even if the CFRP layer 12e is laminated only on a part of the first single plate 11a and the second single plate 11b, this CFRP layer It is possible to prevent the laminated portion 12e from becoming too thick compared to other portions. Therefore, even when the sixth unit plywood 34 is used, the appearance of the membrane musical instrument shell can be prevented from being deteriorated in appearance. In addition, since the average thickness of the plurality of CFRP layers 12e is relatively small in the sixth unit plywood 34, the first single plate 11a and the second single plate 11b are directly stacked without the plurality of CFRP layers 12e. Adhesive strength can be maintained sufficiently. The average width (average length in the circumferential direction) of the plurality of CFRP layers 12e can be the same as the average width of the ring-shaped CFRP layer 12d described above.

  When this sixth unit plywood 34 is used, the shell for membrane instrument is used together with another unit plywood having a CFRP layer laminated on the entire surface of the first veneer 11a and the second veneer 11b. The fifth unit plywood 34 can increase the partial strength while increasing the overall strength by the unit plywood. On the other hand, the shell for a membranous instrument is configured by using, for example, only a plurality of sixth unit plywoods 34 or using only one or more sixth unit plywoods 34 and only one or more single plates. It is easy to prevent the deterioration of the woody sound characteristics easily and surely.

  The membrane musical instrument shell using the sixth unit plywood 34 is arranged in parallel so that a plurality of strip-like CFRP layers 12e are bridged between both end edges of the opposing surfaces of the first veneer 11a and the second veneer 11b. The strength in the central axis direction can be effectively increased. In particular, in the membrane sound instrument shell using the sixth unit plywood 34, since the carbon fibers constituting the plurality of CFRP layers 12e are oriented in the central axis direction, it is easy to sufficiently increase the strength in the central axis direction. . Further, in the membrane sound instrument shell using the sixth unit plywood 34, since the carbon fibers constituting the plurality of CFRP layers 12e are oriented in the central axis direction, the plurality of CFRP layers 12e have anisotropy. Thus, the deterioration of the woody sound characteristic can be suppressed. Furthermore, in the membrane sound instrument shell using the sixth unit plywood 34, a plurality of strip-like CFRP layers 12e are bridged between both end edges of the opposing surfaces of the first single plate 11a and the second single plate 11b. By laminating in parallel, it is possible to reduce the existing area of the plurality of CFRP layers 12e and to easily and reliably suppress the deterioration of the woody sound characteristics.

(7th unit plywood)
The seventh unit plywood 35 in FIG. 13 is a pair of first and second single plates 11a and 11b, and the first single plate 11a and the second single plate 11b, which are orthogonal to each other. The ring-shaped CFRP layer 12f is provided. The seventh unit plywood 35 has no layers other than the first veneer 11a, the second veneer 11b, the pair of CFRP layers 12f, and an adhesive layer (not shown) that bonds these layers. The carbon fibers constituting the pair of CFRP layers 12f are not oriented in a specific direction. The seventh unit plywood 35 is configured similarly to the fifth unit plywood 33 described above except that the carbon fibers constituting the pair of CFRP layers 12f are not oriented in a specific direction.

  When the seventh unit plywood 35 is used, the membrane sound instrument shell is used together with another unit plywood in which a CFRP layer is laminated on the entire surface of the first veneer 11a and the second veneer 11b. The seventh unit plywood 35 can increase the partial strength while increasing the overall strength by the unit plywood. On the other hand, the shell for a membranous instrument is constituted by using only a plurality of seventh unit plywoods 35 or using only one or more seventh unit plywoods 35 and only one or more single plates. It is easy to prevent deterioration of woody sound characteristics.

  As a manufacturing method of the seventh unit plywood 35, for example, a sheet body including a binder mainly composed of a thermosetting resin such as an epoxy resin and a carbon fiber contained in the binder is formed in advance, and the carbon fiber Is bonded to the surface of the first single plate 11a so that the first single plate 11a is along the both ends of the first single plate 11a, and the second single plate 11b is bonded to the surface of the first single plate 11a and the sheet body. Is mentioned.

(Eighth unit plywood)
The eighth unit plywood 36 shown in FIG. 14 is laminated on the first veneer 11a and the second veneer 11b that are directly laminated, and on the opposite surface of the second veneer 11b to the first veneer 11a. A layer 12a is provided. The eighth unit plywood 36 does not have any layers other than the first veneer 11a, the second veneer 11b, the CFRP layer 12a, and an adhesive layer (not shown) that bonds these layers. In the eighth unit plywood 36, the CFRP layer 12a is not laminated between the first single plate 11a and the second single plate 11b, and constitutes an inner peripheral surface. The eighth unit plywood 36 has high strength in the circumferential direction because the carbon fibers constituting the CFRP layer 12a are oriented in the circumferential direction. Moreover, since the wood unit direction of the 1st single board 11a which comprises the radial direction outer surface is orientating the circumferential direction in the 8th unit plywood 36, the intensity | strength with respect to the force applied from a radial direction outer side is high. For this reason, the eighth unit plywood 36 can suppress deformation caused by the force applied from the outside in the radial direction and can increase the strength in the circumferential direction. Suitable for being installed.

[Other Embodiments]
In addition, the shell for membrane sound musical instruments which concerns on this invention can be implemented in the aspect which gave various changes and modifications other than the said aspect. For example, the membrane musical instrument shell only needs to have a CFRP layer laminated on the entire surface or a part of at least one single plate. For example, it may be composed of only one CFRP layer and a plurality of single plates. You may be comprised by one unit plywood which has a layer, and the other unit plywood or single plate which does not have a CFRP layer.

  In the shell for membrane instrument, it is preferable that the CFRP layer is laminated on the opposing surfaces of the pair of single plates in order to provide a woody appearance, but the CFRP layer is not necessarily laminated on the opposing surfaces of the pair of single plates. It is not necessary and may be exposed on the outer peripheral surface side or the inner peripheral surface side.

  Even if the shell for membrane instrument is formed using a unit plywood having a CFRP layer, the configuration of the unit plywood is not limited to the configuration of the above-described embodiment. For example, as shown in FIG. 15, the membrane musical instrument shell may be formed by using a unit plywood 41 formed of a laminate of one single plate 42 and a CFRP layer 43 stacked on the single plate 42. Good. Further, the grain direction of the single plate in the unit plywood used in the shell for the membrane sound instrument and the orientation direction of the carbon fiber of the CFRP layer are not limited to the configuration of the above-described embodiment, and required characteristics. It can be appropriately changed depending on the situation. For example, when one unit plywood has a pair of single plates and a CFRP layer, the grain direction of the pair of single plates and the orientation direction of the carbon fibers constituting the CFRP layer may all be parallel. Moreover, the grain of the single plate may be oriented in a direction other than the circumferential direction or the central axis direction.

  When the membrane musical instrument shell includes a ring-shaped CFRP layer, the CFRP layer does not necessarily have to be laminated along both end edges of the opposing surfaces of the pair of single plates. For example, this CFRP layer may be laminated only along one edge of the opposing surfaces of the pair of single plates, or may be laminated on portions other than both end edges of the opposing surfaces of the pair of single plates.

  When the membrane musical instrument shell includes a strip-shaped CFRP layer, the CFRP layer does not necessarily have to be laminated so as to be bridged between both end edges of the opposing surfaces of the pair of single plates. Moreover, even when it spans between the both edges of the opposing surface of a pair of single plate, the longitudinal direction does not necessarily need to be arranged in parallel with the central axis direction.

  In the membrane sound instrument shell, the ring-shaped CFRP layer and the band-shaped CFRP layer may be laminated on one unit plywood.

  The membrane musical instrument shell can be used for various membrane musical instruments such as various drums, tambourines, congas, bongos, and Japanese drums.

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to the following examples.

[Example 1]
A 1 mm thick single plate (also referred to as “first single plate”) composed of maple, in which wood grain is oriented in the circumferential direction, a 0.1 mm thick CFRP layer in which carbon fiber is oriented in the circumferential direction, and maple A unit plywood made of a laminated body of 1 mm thick single plates (also referred to as “second single plate”) having a wood grain oriented in the central axis direction was manufactured. In this unit plywood, an epoxy adhesive is applied at a coating amount of 70 g / m ² on the laminated surface of the first single plate and the CFRP layer and the laminated surface of the CFRP layer and the second single plate, and each layer is attached. Manufactured by combining. Next, this unit plywood was inserted into the hollow portion 21a of the outer mold 21 in FIG.

Subsequently, a urea-based adhesive was applied at an application amount of 350 g / m ² on the inner peripheral surface of the unit plywood inserted into the hollow portion 21a. Further, a unit plywood having the same configuration as described above is manufactured, and the same adhesive is applied to the outer peripheral surface of the unit plywood in the same amount as described above, and then this unit plywood is inserted into the hollow portion 21a of the outer mold. did. By repeating this process, three unit plywoods are formed on the inner peripheral surface of the outer mold 21 as a first veneer, a CFRP layer, a second veneer, a first veneer, a CFRP layer, a second veneer, and a second veneer. The CFRP layer and the first single plate were stacked in this order. In addition, the adhesive agent is not apply | coated to the internal peripheral surface of the 1st single plate which comprises an innermost surface.

  Next, the inner mold 22 of FIG. 8 was inserted into the inner peripheral surface side of the three unit plywoods superimposed on the inner peripheral surface of the outer mold 21. Subsequently, a heater was attached to the outer periphery of the outer mold 21, and the coating 25 was expanded by supplying compressed air to the air chamber 26 of the inner mold 22 while heating the three unit plywood together with the outer mold 21. Further, after the adhesive was cured, the laminated body of the three unit plywood was taken out from the outer mold 21 and the inner mold 22 to obtain a shell for a musical instrument of Example 1.

[Example 2]
A membrane sound instrument shell of Example 2 was obtained in the same manner as in Example 1 except that the orientation direction of the carbon fibers constituting the CFRP layer was changed to the central axis direction.

[Comparative Example 1]
Using a unit plywood in which the first single plate and the second single plate were directly laminated, a membrane musical instrument shell of Comparative Example 1 was obtained in the same manner as Example 1. The first single plate and the second single plate were bonded together by applying a urea-based adhesive on the laminated surface of the first single plate and the second single plate at an application amount of 350 g / m ² .

<Frequency characteristics>
An acceleration pickup (“S04SG” manufactured by Fuji Ceramics Co., Ltd.) is pasted on the outer periphery of the shell for membrane sound musical instrument of Examples 1 and 2 and Comparative Example 1, and the inner peripheral surface is downward with a finger so that the central axis is in the horizontal direction. The outer peripheral surface was vibrated at an angle of 45 ° obliquely upward with respect to the horizontal direction with a bass drum beater. Table 1 shows the shell frequency by this excitation.

<Attenuation rate>
An acceleration pickup (“S04SG” manufactured by Fuji Ceramics Co., Ltd.) is pasted on the outer periphery of the shell for membrane sound musical instrument of Examples 1 and 2 and Comparative Example 1, and the inner peripheral surface is downward with a finger so that the central axis is in the horizontal direction. The outer peripheral surface was vibrated at an angle of 45 ° obliquely upward with respect to the horizontal direction with a bass drum beater. Table 1 shows the logarithmic decay rate in the primary vibration mode by this excitation.

[Evaluation results]
As shown in Table 1, it can be seen that the membrane musical instrument shell of Example 1 has a higher resonance frequency than the membrane musical instrument shell of Comparative Example 1, and thus can easily produce a bright and clear sound. . Further, it can be seen that the membrane musical instrument shell of Example 1 has a lower attenuation rate than the membrane musical instrument shell of Comparative Example 1, and it is easy to produce a sound with good sound at a high volume. The shell for the musical instrument of Example 1 is a film musical instrument of Comparative Example 1 as a result of the circumferential strength being increased and the roundness being improved by the carbon fibers constituting the CFRP layer being oriented in the circumferential direction. It is thought that the sound quality characteristics have been improved compared to the shell. Further, it can be seen that the membrane musical instrument shell of Example 2 has a lower attenuation rate than the membrane musical instrument shell of Comparative Example 1, and it is easy to produce a sound with good sound at a high volume. The shell for the musical instrument of Example 2 has a lower attenuation than the shell for the musical instrument of Comparative Example 1 because the attenuation of the epoxy adhesive that bonds the CFRP layer is lower than that of the urea adhesive. It is thought that it was kept low.

  As described above, the membrane musical instrument shell of the present invention is suitable as a high quality membrane musical instrument shell because it can reduce the weight and improve the strength and suppress the deterioration of the woody sound characteristics. .

1 Shell for musical instrument 2 Head membrane 11a First single plate 11b Second single plate 12a, 12b, 12c, 12d, 12e, 12f CFRP layer 13 First unit plywood 14 Second unit plywood 21 Outer die 21a Hollow part 22 Inside Mold 23 Core portion 24 Flange portion 25 Coating 26 Air chamber 31 Third unit plywood 32 Fourth unit plywood 33 Fifth unit plywood 34 Sixth unit plywood 35 Seventh unit plywood 36 Eighth unit plywood 41 Unit plywood 42 Single plate 43 CFRP layer

Claims (5)

A cylindrical membrane sound instrument shell in which a plurality of single plates are laminated,
A membrane musical instrument shell comprising a carbon fiber reinforced plastic (CFRP) layer laminated on the whole surface or a part of at least one veneer.   The membrane sound instrument shell according to claim 1, wherein the carbon fibers constituting the CFRP layer are oriented in one direction.   The membrane sound instrument shell according to claim 1 or 2, wherein the CFRP layer is laminated on the entire surface of a pair of veneers that are orthogonal to each other. A pair of ring-shaped CFRP layers;
The membrane sound instrument shell according to claim 1, 2 or 3, wherein the pair of CFRP layers are laminated along both end edges of opposing surfaces of a pair of single plates in which wood is orthogonal. Comprising a plurality of strip-like CFRP layers;
The membrane sound according to claim 1, 2 or 3, wherein the plurality of CFRP layers are laminated in parallel so as to be bridged between both end edges of the opposing surfaces of a pair of single plates in which the wood is orthogonal. Instrument shell.

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