JP4752481B2 - Sound source unit for keyboard-type sound board percussion instrument and method of manufacturing the same - Google Patents

Description

The present invention relates to a sound source unit for a keyboard-type sound board percussion instrument that emits a musical tone having a specific pitch by being struck and vibrated, and a method for manufacturing the same.

  Conventionally, a plurality of soundboards for keyboard-type soundboard percussion instruments are provided as shown in Patent Document 1 below, and each has a unique pitch. In general, the sound board is a flat plate. Further, in many keyboard-type soundboard percussion instruments, each soundboard can produce a unique pitch by mainly changing the overall length of the soundboard.

On the other hand, as shown in Patent Document 2 below, there is also known one in which the thickness of the sound board is changed in the longitudinal direction. In this sound board, the ratio of the frequency of the primary to tertiary modes is set to 1: 4: 8 by cutting the vicinity of the central portion in the longitudinal direction, etc., thereby improving the harmony of the chord, the sense of volume, and the sense of pitch. .
Japanese Utility Model Publication No. 05-081895 Japanese Patent Application Laid-Open No. 08-202351

  However, also in the above-mentioned Patent Document 2, the overall length of the sound board becomes longer as the pitch is lower, and in particular, in the low sound range, it is wider and the entire length becomes very long. Therefore, there is a problem that the degree of freedom in design is low because the size of each sound board is largely limited. Therefore, for example, in a keyboard-type soundboard percussion instrument in which a large number of soundboards covering a wide sound range are arranged, the instrument itself is increased in size.

The present invention has been made in order to solve the above-described problems of the prior art, and an object of the present invention is to provide a keyboard-type sound board that facilitates shortening and reducing the overall length of the sound board and increasing the degree of freedom in design. It is an object to provide a sound source unit for a percussion instrument and a manufacturing method thereof.

In order to achieve the above object, the sound source unit for a keyboard-type sound board percussion instrument according to claim 1 of the present invention becomes a node in vibration closer to the first and second end portions than the central portion (31) in the longitudinal direction. When the position is supported as the first and second supported parts (36, 37) and hit through the action mechanism, a plurality of sounds for at least the low range are generated that vibrate each tones with their own specific pitches by vibrating . A sound source unit for a keyboard-type sound board percussion instrument having a sound board , wherein each of the plurality of sound boards is integrally formed of a single material, and each of the plurality of sound boards includes the first and second sound boards . First and second mass concentrating portions (32, 33) provided at positions closer to the first and second end portions than the first and second supported portions at the end portions, and the central portion in the longitudinal direction And the first supported portion, and between the longitudinal center portion and the second supported portion. First provided each have a second thin portion (34, 35), said first, second mass concentrating portions, the longitudinal central portion and said first, relative to the second thin portion Thick in the plate thickness direction, and the first and second thin portions are thinner in the plate thickness direction than the central portion in the longitudinal direction, and the thicknesses of the first and second mass concentrating portions vary depending on the sound range. It is characterized by being thicker .

Preferably, the first and second mass concentrating portions and the central portion in the longitudinal direction protrude to one side in the plate thickness direction with respect to the first and second thin portions. 2 ).

Preferably, the first, second supported portion, characterized in that the width direction of the tone plate is engaging portion formed along substantially (claim 3).

In order to achieve the above object, a sound source unit manufacturing method for a keyboard-type sound board percussion instrument according to claim 4 of the present invention is a vibration node closer to the first and second end portions than the central portion in the longitudinal direction. A keyboard having at least a plurality of low-pitched soundboards that each vibrate a musical tone having a specific pitch when vibrated through an action mechanism while supporting the position as first and second supported parts. A method of manufacturing a sound source unit for a type sound board percussion instrument, wherein a long member (38) having a rectangular cross section made of a single material is used for the first and second supported members when the plurality of sound boards are manufactured. The first and second mass concentrating portions are formed at the first and second end portions by removing them by cutting and / or grinding to positions closer to the first and second end portions than the positions to be the portion. And between the longitudinal center portion and the first supported portion, and the front Between the longitudinal center portion and the second supported portion, the first respectively to form a second thin portion, in which, the elongate member, by removing from one direction, the first, The second mass concentrated portion is left thicker in the plate thickness direction than the longitudinal central portion and the first and second thin portions, and the first and second thin portions are compared to the longitudinal central portion. It is characterized in that it is formed thin in the plate thickness direction, and the thicknesses of the first and second mass concentrating portions are made different depending on the sound range so that the lower sound range is thicker .

  In addition, the code | symbol in the said parenthesis is an illustration.

  According to the first aspect of the present invention, it is possible to facilitate the shortening of the overall length and the narrowing of the sound plate, thereby increasing the degree of freedom in design.

According to the second aspect , the sound board can be formed by cutting or the like only on one side in the plate thickness direction, and the processing becomes easy.

According to the third aspect , for example, a plurality of sound plates can be collectively supported by the string-like member via the engaging portion.

According to the fourth aspect, it is possible to facilitate the shortening of the overall length and the narrowing of the sound board and to increase the degree of freedom in design. Further, the sound board can be easily manufactured.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(First embodiment)
FIG. 1 is a left side view of a keyboard instrument configured as a keyboard-type sound board percussion instrument to which a sound board according to a first embodiment of the present invention is applied. In brief, the keyboard instrument 10 looks like an upright piano in appearance, but does not have strings. Instead, a sound board similar to the Celesta sound board is provided in the upper half 10a of the keyboard instrument 10, and the sound board is struck and vibrated to generate sound. It also has a box. Moreover, as a mechanism for hitting the sound board, a mechanism similar to an action mechanism for a grand piano is provided instead of an upright piano.

  Hereinafter, the player side of the keyboard instrument 10 is referred to as the front, and the left and right direction is referred to the player. A pedal box 11 is provided below the keyboard instrument 10, and a damper pedal 12 extends from the pedal box 11 forward.

  By the way, the keyboard instrument 10 is similar to the Celesta, but in the Celesta, a flat sound board is generally used as a sound generator. The sound board 30 (described later in FIG. 5) used as the sound generator used in the present embodiment has a thickness and is more like a rod than a flat plate, so the expression “sound board” may not be appropriate. However, since the word “sound board” is commonly used in Celesta, the sounding body used in the keyboard instrument 10 is referred to as “sound board 30”. Although details will be described later, in the present embodiment, the shape of the resonance chamber is devised, and the width of each resonance chamber is appropriately secured, while the one-stage configuration of the sound plate group and the resonance box is realized. is there.

  2 is a right sectional view showing the internal configuration of the upper half 10a of the keyboard instrument 10, FIG. 3 is a front view showing the internal configuration of the upper half 10a, and FIG. 4 shows the internal configuration of the upper half 10a. It is a top view.

  As shown in FIG. 2, a gutter 15 is arranged on the shelf plate 14 at the lower part of the upper half 10 a, and a front gutter 16 is provided in the front part of the gutter 15. A support member 19 is provided on the heel 15, and a plurality of white keys 27 and black keys 28 of the keyboard KB swing in the vertical direction with the balance pins 62 and 63 provided on the support member 19 as fulcrums (seesaw motion). It is supported freely. A mouth bar portion 17 covers the front portion of the heel 16 over the entire key width (see also FIG. 4). In FIG. 3, the illustration of the mouth bar portion 17 is omitted.

  In addition, an action mechanism 20 is disposed in the upper part of the rear half of the basket 15 via an action bracket 22. The action bracket 22 and the action mechanism 20 are arranged corresponding to the keys 27 and 28, and the action mechanism 20 has the same configuration as the action mechanism of the grand piano. Further, above these action mechanisms 20, a sound source unit UNT including a wooden resonance box 50 and a plurality of sound plates 30 (sound plate group 30G) is disposed. The sound board 30 is provided corresponding to the keys 27 and 28. By pressing the corresponding keys 27 and 28, the hammer body 23 rotates upward, and the hammer felt 24 strikes the corresponding sound plate 30, so that the sound plate 30 vibrates and generates sound, and the sound is generated. Resonate in the resonance box 50. Below the action mechanism 20, the shelf plate 14 is provided with a sound emission hole 14 a.

  A rotating member 64 is provided above the rear end of each key 27, 28 corresponding to each key 27, 28, and each rotating member 64 is provided with a damper via a damper wire 25 (see also FIG. 3). A felt 26 is provided. When the damper pedal 12 is not depressed, the damper felt 26 is in contact with the upper surface of the rear end portion of the corresponding sound plate 30. When the key is depressed, the damper felt 26 is separated from the sound plate 30 via the corresponding damper wire 25. On the other hand, a pedal connecting rod 13 is connected to the damper pedal 12. When the damper pedal 12 is stepped on, the entire damper felt 26 is lifted through the pedal connecting rod 13 and the entire damper wire 25.

  As shown in FIGS. 3 and 4, support portions 29 </ b> L and 29 </ b> R are fixed inside the side plates 18 </ b> L and 18 </ b> R constituting the left and right side portions of the keyboard instrument 10. As will be described later, the sound source unit UNT is configured integrally with a resonance box 50 in which a sound plate group 30G is mounted so as to be able to vibrate, and can be handled as a unit when attached and removed. The left and right ends of the resonance box 50 are screwed and fixed onto the support portions 29L and 29R with screws (not shown), so that the sound source unit UNT is accommodated in the upper half portion 10a.

  Next, the configuration of the sound source unit UNT will be described. FIG. 5A is a plan view of one sound plate 30, and FIG. 5B is a right side view of the sound plate 30. 6 is a front view of the sound source unit UNT, FIG. 7 is a cross-sectional view taken along line AA of FIG. 6, and FIG. 8 is a bottom view of the sound source unit UNT.

  First, the sound board group 30G will be described. The sound board group 30G includes sound boards 30 corresponding to the number of keys, and each sound board 30 is struck by the hammer felt 24 and vibrates to generate a sound with a unique pitch. Each of the sound boards 30 has a shape such as its entire length that is individually different (see FIGS. 7, 8, and 9 (c) to 9 (e)), thereby generating a specific pitch. . The sound board group 30G is arranged in a pitch order in the key arrangement direction so that adjacent ones having specific pitches are adjacent to each other, and is configured in one stage (FIGS. 3, 6 to 6). 8). By the way, the action mechanism 20 is also arranged in the key arrangement direction corresponding to the arrangement of the corresponding sound boards 30, and is configured in one stage. 5 (a) and 5 (b) show a sound plate 30 that belongs to the low sound region 50A (described later).

  As shown in FIGS. 5 (a) and 5 (b), the sound board 30 has support holes 36 and 37 at positions that become nodes in vibration near the front end and the rear end rather than the central portion in the longitudinal direction. Is formed. The support holes 36 and 37 are through holes through which the connecting string 44 (see FIGS. 3, 6, and 8) is passed. The sound plate 30 having a lower specific pitch is arranged on the left side, and since the overall length is long, the distance between the support holes 36 and 37 is correspondingly long. Accordingly, the support hole 36 / support hole 37 of each sound board 30 is substantially along the width direction, but strictly speaking, on the left side so as to be substantially coaxial with the support holes 36, 37 of the adjacent sound board 30. As it goes, it is inclined to the front side / rear side (see FIG. 5A).

  The support holes 36 and 37 are provided at positions that become nodes in vibration, and the sound board 30 generates sound efficiently when the support holes 36 and 37 are vibrated. Further, the central portion in the longitudinal direction becomes a portion corresponding to the antinode in vibration (hereinafter, simply referred to as “abdominal portion 31”), and the center of the abdominal portion 31 is in a position corresponding to the center of the antinode during vibration (hereinafter, “abdominal center 31P”). "). The lower surface of the sound plate 30 is flat. The front end portion and the rear end portion of the sound plate 30 are formed to be thick by protruding upward, and are a first mass concentration portion 32 and a second mass concentration portion 33 in which mass is concentrated. By providing the first and second mass concentrating parts 32 and 33, it is possible to shorten the overall length, particularly in the sound board 30 on the bass side.

  In the vertical direction (plate thickness direction), the abdomen 31 of the sound board 30 is convex upward, but is thinner than the first and second mass concentrating parts 32 and 33. Moreover, between the abdominal part 31 and the 1st mass concentration part 32, and between the abdominal part 31 and the 2nd mass concentration part 33, it is the 1st thin part 34 and the 2nd thin part 35 thinner than the abdominal part 31. .

  The resonance box 50 of the sound source unit UNT is composed of a low-frequency region portion 50A, a mid-frequency region portion 50B, and a high-frequency region portion 50C in order from the low sound side (see FIG. 6). The width of the sound plate 30 in the left-right direction is uniform over the entire length, but those corresponding to the same sound range portion have the same width. That is, the sound plate 30 corresponding to the low sound region portion 50A is the widest, and the sound plate 30 corresponding to the high sound region portion 50C is the narrowest.

  The sound plate 30 is integrally formed of a single material such as aluminum, aluminum alloy, or steel. As a manufacturing method, for example, a long member having a rectangular cross section made of a single material (pre-processing member 38 shown in FIG. 5B) is processed from one direction (upper side in FIG. 5B). Can be formed. That is, the above-described abdomen 31, first, and second are removed by cutting and / or grinding from one direction from a position closer to the front end than the support hole 36 to a position closer to the rear end than the support hole 37. Processing is performed so that the two mass concentration portions 32 and 33 and the first and second thin portions 34 and 35 are formed.

  Fig.9 (a) is a side view of the one fastener 40 for hold | maintaining the sound board group 30G collectively. FIG. 4B is a partially enlarged view of the fastener 40, FIG. 4C is a side view of the sound plate 30 and the fastener 40 corresponding to the high-frequency region 50C, and FIG. The side view of the sound board 30 and the fastener 40 corresponding to the part 50B, FIG. 9E is a side view of the sound board 30 and the fastener 40 corresponding to the low sound region part 50A.

  In general, in the Celesta, the length of the sound board is originally shorter on the higher sound side. Therefore, the sound board 30 belonging to the middle sound region portion 50B and the high sound region portion 50C is thinner than the sound plate 30 belonging to the low sound region portion 50A in the thickness corresponding to the first and second mass concentration portions 32 and 33. (See FIGS. 9C and 9D). In addition, the sound board 30 belonging to the high sound region portion 50C is not provided with one corresponding to the first and second thin portions 34 and 35 (see FIG. 9C).

  As shown in FIG. 9A, the fastener 40 is made of metal or the like, and has a locking groove 42 to be locked to the connecting string 44 and a pin portion 41 driven into the resonance box 50. . The width of the locking groove 42 is slightly smaller than the connecting string 44, and the string receiving portion 43 on the back side of the locking groove 42 has a cross-sectional shape that is a missing circle having an inner diameter substantially the same as the diameter of the connecting string 44. (See FIG. 9B). As a result, the connecting cord 44 can be passed through the engaging groove 42 from the opening side of the engaging groove 42 and easily engaged with the receiving portion 43, while the connecting string 44 can be easily removed from the receiving portion 43 during performance. There is no way to leave. Here, all the fasteners 40 have the same configuration with no distinction between left and right, etc., so that the number of types of parts does not increase.

  When assembling the sound board group 30G with respect to the resonance box 50, first, the sound board group 30G is gathered together with one connecting string 44. For example, the sound board group 30G is placed side by side in the order of pitches, and the connecting cords 44 are passed through the support holes 36 and 37 so that both ends of the connecting strap 44 are located on the left side of the lowest sound plate 30. (In FIG. 8, the connecting string 44 is rotated counterclockwise from the lower left of the figure).

  That is, the connecting cords 44 are sequentially passed through the support holes 36 on the front side in order of pitches from the lowest sound plate 30. When the connecting string 44 passes through the support hole 36 on the front side of the sound plate 30 on the highest pitch side, the connection string 44 is next connected to the support hole 37 on the rear side in order of the pitch from the sound plate 30 on the highest pitch side. Are sequentially penetrated. Finally, both ends of the connecting cord 44 are connected at the left end position of the sound plate 30 on the lowest side. The connecting position may be anywhere, and the connecting string 44 may be composed of two or more, and may be connected by connecting it halfway.

  As shown in FIGS. 7 and 8, the resonance box 50 includes a wooden front common wall 51 and a rear common wall 52 that extend over substantially the entire length in the key arrangement direction. The distance between the front common wall 51 and the rear common wall 52 increases toward the low frequency range, and has a “C” shape when viewed from the left. On the lower surfaces of the front common wall 51 and the rear common wall 52 of the resonance box 50, positioning holes (not shown) are provided in advance so that the pin portions 41 of the fasteners 40 can be easily fitted. This positioning hole is set so that each sound board 30 is arranged at an appropriate position.

  In order to mount the sound board group 30G grouped together with the connecting string 44 to the resonance box 50, first, the resonance box 50 is placed upside down, for example, the front common wall 51 of the resonance box 50, the rear The pin portion 41 of the fastener 40 is temporarily inserted into each of the positioning holes of the side common wall 52 and then driven with a tool such as a hammer. This operation is performed for all the fasteners 40. Then, a group of sound board groups 30G are placed on each lower surface of the front common wall 51 and the rear common wall 52 of the resonance box 50, and a string connected to the receiving portion 43 of the fastener 40 between the sound boards 30 is placed. 44 is engaged. Thereafter, if the top and bottom of the resonance box 50 are corrected, the sound board group 30G is held in a state suspended from the resonance box 50 by the connecting string 44 via the fastener 40 as shown in FIGS. Become. Thereby, the sound source unit UNT in which the resonance box 50 and the whole sound board 30 are unitized is configured.

  In the sound source unit UNT, the abdomen 31 of each sound plate 30 is close to the opening side (lower side) of the resonance chamber RM (described later) of the resonance box 50 and can be independently vibrated. The interval at the time of attachment between the adjacent sound boards 30 is provisionally determined by the thickness of the fastener 40. Therefore, the position of the pin portion 41 of the fastener 40 can be easily aligned with the positioning hole, and the operation is simple. It is. As shown in FIG. 8, since the sound board group 30G is divided into two groups in the middle of the key arrangement direction, the fastener 40 is provided by providing at least a pair of front and rear positioning holes in each of the left and right groups. The interval at the time of attaching each sound board 30 may be automatically defined by the thickness of the sound board. It is not essential to provide the positioning holes in advance.

  As shown in FIG. 6, the resonance box 50 has different types among the low sound region portion 50A, the middle sound region portion 50B, and the high sound region portion 50C. The low frequency range portion 50 </ b> A of the resonance box 50 is a Helmholtz type and has the same number of resonance chambers RM <b> 1 as the sound plates 30 corresponding to the sound plates 30. The middle sound range portion 50 </ b> B is a closed tube type and has the same number of resonance chambers RM <b> 2 as the sound plates 30 corresponding to the sound plates 30. Further, the high sound region portion 50 </ b> C is a collective resonance box, and has one resonance chamber RM <b> 3 common to the plurality of sound plates 30.

  As shown in FIG. 7, in the resonance box 50, the front common wall 51 and the rear common wall 52 are connected by a plurality of partition plates 53 having different lengths. The partition plate 53 is a flat plate parallel to each other along the front-rear direction and the vertical direction, and is provided from the lower opening to the upper end as shown in FIG. The front and rear portions of the partition plate 53 are fixed to the front common wall 51 and the rear common wall 52 by adhesion or the like, respectively.

  As shown in FIG. 7, in any sound range portion, two sound plates 30 correspond to each other between adjacent partition plates 53 in the key arrangement direction. Further, the interval between adjacent partition plates 53 is slightly larger than the width of two corresponding sound plates 30. Furthermore, in the low sound region portion 50 </ b> A and the middle sound region portion 50 </ b> B, the adjacent partition plates 53 are connected by diagonal plates 54 and 55. Between the adjacent partition plates 53, the two resonance chambers RM1 are formed by the oblique plate 54, and the two resonance chambers RM2 are formed by the oblique plate 55, respectively.

  As shown in FIG. 6, one lid member 56 common to the low frequency range portion 50A is fixed to the upper end of the partition plate 53 of the low frequency range portion 50A, and the upper portions of all the resonance chambers RM1 are collectively closed. ing. Further, in the middle sound range portion 50B, one lid member 57 is fixed to each of the two resonance chambers RM2 at the upper end of the partition plate 53, and the upper portion of each resonance chamber RM2 is closed. Further, one lid member 58 common to the high sound region portion 50C is fixed to the upper end of the partition plate 53 of the high sound region portion 50C, and the upper portion of the resonance chamber RM3 is closed.

  The oblique plates 54 and 55 are both flat plates along the vertical direction, and the oblique plates 54 are parallel to each other, and the oblique plates 55 are also parallel to each other. Since the structures and functions of the oblique plates 54 and 55 are basically the same, the structures of the oblique plate 55 and the resonance chamber RM2 of the mid-range part 50B will be mainly described.

  FIG. 10 is a partially enlarged view of the mid-range part 50B of the sound source unit UNT shown in FIG. Here, since the two resonance chambers RM2 will be described as a representative, the resonance chamber RM2 and the partition plate 53 and the sound plate 30 corresponding to the resonance chambers RM2 are given parentheses “(1), (2)”, respectively. To distinguish. The diagonal plate 55 that connects the two partition plates 53 (1) and 53 (2) has a rear portion from the center in the front-rear direction of the partition plate 53 (1), and a front portion from the center in the front-rear direction of the partition plate 53 (2). It is fixed with adhesive etc.

  On the other hand, in the sound source unit UNT, the center positions of the hammer felt 24 (see FIG. 2) in the front-rear direction and the left-right direction coincide with the belly center 31P of the corresponding sound board 30 (see FIGS. 5A and 5B). Yes. Further, the antinode centers 31P of all the sound boards 30 have the same position in the front-rear direction, and the virtual straight line L1 shown in FIG. The straight line L1 also passes through all the resonance chambers RM1 to RM3 in plan view.

  As shown in FIG. 10, the sound plates 30 (1) and 30 (2) are arranged between the partition plates 53 (1) and 53 (2). Of the space between the partition plates 53 (1) and 53 (2), the front portion of the oblique plate 55 is the resonance chamber RM 2 (1), and the rear portion is the resonance chamber RM 2 (2). In plan view, the antinode 31P of the sound plate 30 (1) is included in the resonance chamber RM2 (1), and the antinode 31P of the sound plate 30 (2) is included in the resonance chamber RM2 (2). Therefore, the sounds of the sound plates 30 (1) and 30 (2) resonate in the resonance chambers RM2 (1) and RM2 (2) that correspond one-on-one. Thus, the abdominal centers 31P of all the sound plates 30 are located in the corresponding resonance chambers RM in plan view.

  In general, if the resonance chamber of the resonance box is too narrow, it cannot perform a good resonance function. However, in the present embodiment, the resonance chambers RM2 (1) and RM2 (2) have a sufficient width in the key arrangement direction, and a good resonance is realized. Moreover, the same number of sound plates 30 as the keys 27 and 28 are arranged in the same width in the key arrangement direction, and only two widths of the sound plate 30 are required to secure two resonance chambers RM2. . Thereby, it is not necessary to divide the action mechanism 20 and the sound board 30 into two stages as in the prior art with respect to the keyboard KB having a general structure, and a one-stage structure is realized.

  In the low sound region portion 50A, the angle and length of the slant plate 54 are different from those of the slant plate 55 due to the difference in the width of the sound plate 30 compared to the mid sound region portion 50B (see FIG. 7). The basic configuration is the same. As shown in FIGS. 6 and 7, in the bass region 50A, a port forming member 60 is provided below each resonance chamber RM1. A port is formed by the two partition plates 53, the oblique plate 54, and the port forming member 60 in the opening of each resonance chamber RM 1 (except for the left end portion). In general, in a Helmholtz type resonance box, not only the capacity of the box but also the length and cross-sectional area of the port affect the pitch of resonance. For example, even if the boxes have the same capacity, if the length of the port is increased or the cross-sectional area is reduced, the resonant pitch is lowered. Also in the present embodiment, by appropriately setting the shape of the port forming member 60, the length and cross-sectional area of the port of each resonance chamber RM1 is adjusted, and the sound of the corresponding tone plate 30 is good. It is configured to resonate with.

  According to the present embodiment, the sound board 30 belonging to the low frequency range portion 50A is provided with the first and second mass concentration portions 32 and 33 closer to both end portions than the support holes 36 and 37, and the abdomen 31 and the first portion. First and second thin portions 34 and 35 are provided between the mass concentrating portion 32 and between the abdominal portion 31 and the second mass concentrating portion 33, and are integrally formed of a single material (FIG. 5). (Refer to (a) and (b)). This facilitates shortening the overall length and narrowing of the sound plate 30 and increases the degree of design freedom. Therefore, while covering a wide sound range, it contributes to the miniaturization of the musical instrument itself. In particular, since the sound board for bass generally tends to be long, the sound board 30 shown in FIGS. 5A and 5B is suitable for bass.

  Further, the sound board 30 can be easily manufactured by removing the pre-processing member 38, which is a long member having a rectangular cross section made of a single material, from one direction by cutting or the like only on one side in the plate thickness direction. . Therefore, it is easy to manufacture, and it is easy to make the width common among the plurality of sound plates 30 having different pitches. In the sound source unit UNT, three types can be used.

  Further, according to the present embodiment, the plurality of sound plates 30 are attached to the resonance box 50 so as to vibrate in the vicinity of the opening side of the corresponding resonance chamber of the resonance box 50 so that the resonance box 50 and the plurality of sounds can be obtained. Since the plate 30 is unitized, the sound source unit UNT can be easily replaced while maintaining the positional relationship between the resonance box 50 and the sound plate 30 appropriately. Thereby, for example, by changing to a sound source unit having a different configuration of the sound board or the resonance box, it is possible to easily change the timbre while being an acoustic sound board percussion instrument. Further, since the sound source unit UNT can be easily replaced, maintenance work of the sound plate group 30G or the resonance box 50 is also easy.

Further, the plurality of sound plates 30 are held in common so as to be able to vibrate by the connection string 44, and the connection string 44 is attached to the resonance box 50 by the plurality of fasteners 40. In particular, the position of the node in the vibration of the sound board 30 is increased in the plate thickness direction, so that the support holes 36 and 37 can be provided in a direction substantially along the key arrangement direction instead of the vertical direction. It is a thing. Support holes 36, 3
7 is along the key arrangement direction, and as described above, the sound board group 30G can be collectively supported in a state suspended from the resonance box 50 by the connecting string 44. As a result, the sound board group 30G can be handled collectively, and can be attached to and detached from the resonance box 50 as a whole, thereby facilitating the work of attaching and replacing the sound board 30. In addition, since the support holes 36 and 37 are opened at the node positions of the sound plate 30, good sound generation is not hindered.

  Moreover, since the interval at the time of the attachment between the adjacent sound boards 30 is provisionally determined by the fastener 40, the work of attaching and replacing the sound board 30 can be further facilitated.

  Note that the support holes 36 and 37 do not necessarily have to be through holes, and it is sufficient that the plurality of sound plates can be collectively supported by a string-like member such as the connection string 44. Therefore, for example, a groove having a partially-circled cross section in which the lower surface side of the sound board 30 is open may be used. Further, from the viewpoint of grouping the plurality of sound plates 30 together, it is not limited to the string such as the connecting string 44. Further, it is not essential to group all the sound boards 30 together, and the sound board group 30G may be divided into two or more groups.

  Also according to the present embodiment, in the low sound region portion 50A and the middle sound region portion 50B, the width in the key arrangement direction of the resonance chambers RM1 and RM2 is ensured to be equal to or larger than the width of the two corresponding sound plates 30. Therefore, good resonance can be realized. Moreover, the resonance chambers RM1 and RM2 are defined so as to overlap in the front view, so that the length of the resonance box 50 in the key arrangement direction can be shortened while maintaining an appropriate width. It becomes easy. As a result, the one-stage configuration of the sound plate group G and the resonance box 50 can be realized for one musical instrument.

  Further, since the virtual straight line L1 passes through all the resonance chambers RM1 to RM3 and the positions of the antinodes 31P (see FIGS. 5A and 5B) of all the sound boards 30 are the same, It is possible to unify the operational feeling among the sound plates 30. Furthermore, the sound board group G can be made compact in the longitudinal direction of the sound board 30.

  The resonance chambers RM1 and RM2 are defined by a plurality of parallel partition plates 53 that connect the front common wall 51 and the rear common wall 52, and diagonal plates 54 and 55 that connect between the adjacent partition plates 53. Therefore, the resonance chamber can be defined with a simple configuration. In particular, since the plurality of partition plates 53 are parallel to each other, manufacturing is easy.

  Also according to the present embodiment, as described above, the one-stage configuration of the sound board group G and the resonance box 50 can be realized for one musical instrument, compared with the conventional upper and lower two-stage configuration, A long connecting rod for transmitting the key pressing operation to the lower striking portion group is not necessary, and the configuration is simple and the weight can be easily reduced. Further, since the position of the sound board 30 is the same in the vertical direction for the one corresponding to the white key 27 and the one corresponding to the black key 28, it is easy to achieve an acoustic balance between the two. Moreover, unlike the case of the two-stage configuration, the sound emission from the sound plate 30 is not blocked by the lower sound plate group, the striking portion group, and the resonance box. Therefore, it is possible to simplify the configuration as a musical instrument to reduce the weight, to easily unify the key operation feeling, and to achieve efficient sound emission with balanced sound. Moreover, since the sound emitting holes 14a are provided in the shelf board 14 below the action mechanism 20, sound can be emitted directly from the sound board 30 to the outside, and the sound emission efficiency can be improved.

(Second Embodiment)
In the second embodiment of the present invention, the configuration of the resonance box 50 of the sound source unit UNT is different from that of the first embodiment, and the others are the same. FIG. 11 is a partial enlarged view of the mid-range part of the resonance box in the keyboard-type sound board percussion instrument to which the sound board of the present embodiment is applied, and corresponds to FIG.

  In the first embodiment, both ends of the plurality of partition plates 53 are connected to the front common wall 51 and the rear common wall 52 in the low sound region portion 50A and the middle sound region portion 50B. In the embodiment, as shown in FIG. 11, one end of a plurality of partition plates 65 having a length about half of the partition plate 53 is connected to one of the front common wall 51 or the rear common wall 52. The configuration of the partition plate 65 other than the length is the same as that of the partition plate 53.

  Further, in the first embodiment, the adjacent partition plates 53 are connected by the diagonal plates 54 and 55. However, in the second embodiment, as shown in FIG. In the sound range portion 50 </ b> B, the other ends of the adjacent partition plates 65 (the end portions on the side not connected to the front common wall 51 or the rear common wall 52) are connected by an oblique plate 66. Therefore, one resonance chamber RM4 is formed by the two adjacent partition plates 65 and the two diagonal plates 66 connected to the other ends of the two partition plates 65.

  Also in the resonance box 50 shown in FIG. 11, the antinode centers 31P (see FIGS. 5 (a) and 5 (b)) of all the sound boards 30 have the same position in the front-rear direction. A virtual straight line L1 passing through 31P also passes through all the resonance chambers RM4. Further, in the low sound region portion 50A and the middle sound region portion 50B, the resonance chamber RM4 overlaps with the adjacent resonance chamber RM4 in a front view, and the width in the key arrangement direction of each resonance chamber RM4 is equal to that of the corresponding sound plate 30. More than two widths are secured.

  According to the present embodiment, the same effects as those of the first embodiment can be obtained. Further, since the antinode center 31P of the corresponding sound plate 30 is located in the center of the resonance chambers RM4 in the key arrangement direction, it is more advantageous than the first embodiment in realizing good resonance.

  It should be noted that, in the low sound region portion 50A and the middle sound region portion 50B, an appropriate width of the resonance chamber is ensured to realize good resonance, and a single-stage structure of the resonance box is realized together with the sound plate group for one musical instrument. In particular, the following conditions should be satisfied. That is, each of the plurality of resonance chambers overlaps with another resonance chamber in a front view, and the maximum width of each resonance chamber in the arrangement direction of the sound plates is equal to or larger than the width of two corresponding sound plates. I just need it. The material of any part of the resonance box 50 is not limited to wood. For that purpose, the partition plate and the diagonal plate disposed between the front common wall 51 and the rear common wall 52 may be integrally formed with a resin or the like so that a plurality of resonance chambers are formed. The front common wall 51 and the rear common wall 52 together with the partition plate and the diagonal plate may be integrally formed in a mesh shape so that one mesh becomes one resonance chamber.

  Moreover, although it is inferior in the effect compared with 1st, 2nd embodiment, the modification shown next can be employ | adopted about a resonance box. 12A to 12D are partial cross-sectional views showing modifications of the resonance box.

  For example, as shown in FIG. 12 (a), diagonal partition plates 71 are arranged between the front common wall 51 and the rear common wall 52 so that the angles thereof are staggered, and between adjacent partition plates 71. Alternatively, one resonance chamber may be formed.

  Further, as shown in FIGS. 2B and 2C, a plate member 73 is disposed between the front common wall 51 and the rear common wall 52 along the key arrangement direction, and the plate member 73 and the front common wall are arranged. By connecting a plurality of partition plates 72 between the plate member 73 and the rear common wall 52, the resonance chambers may be formed in two stages in the front-rear direction.

  Alternatively, as shown in FIG. 4D, two plate members 73 are disposed between the front common wall 51 and the rear common wall 52, and between the two plate members 73, the front plate member 73 and the front side. By connecting a plurality of partition plates 72 between the common walls 51 and between the rear plate member 73 and the rear common wall 52, resonance chambers may be formed in three stages. The number of steps in the front-rear direction is not limited to two or three.

  Incidentally, in the modification shown in FIG. 12A, the plurality of partition plates 71 are not parallel to each other, which is disadvantageous in terms of manufacturability. In addition, the modified examples shown in FIGS. 12B to 12D are disadvantageous in that the front and rear positions of the antinode 31P of the sound plate 30 cannot be unified.

(Third embodiment)
In the third embodiment of the present invention, the positions of the keyboard KB and the action mechanism 20 in the key arrangement direction are variably configured with respect to the sound source unit. Therefore, the configuration of the tone generator unit UNT is the same as that of the first embodiment except for the keyboard KB and the movable mechanism of the action mechanism 20.

  FIG. 13 is a front view showing an internal configuration of a keyboard instrument configured as a keyboard-type sound board percussion instrument to which the sound plate according to the present embodiment is applied, and mainly shows a right half portion. In the keyboard instrument 100, a hook portion 115 is disposed on the shelf board 14, and a keyboard action unit KACT including a keyboard KB and an action mechanism 20 is disposed on the hook portion 115. And the collar part 115 is comprised so that it can move right and left with respect to the shelf board 14 similarly to moving left and right (key arrangement direction) by operation of a shift pedal in a grand piano. However, the movement amount is set to such an extent that transposition is possible (for example, 5 degrees).

  A transposing pedal 81 is provided below the keyboard instrument 100 in addition to the damper pedal 12, and a connecting rod 82 is connected to the transposing pedal 81. Further, an L-shaped link 84 is provided so as to be pivotable clockwise around a pivot shaft 85 provided in the keyboard instrument 100 main body. One end of an L-shaped link 84 is connected to the connecting rod 82 so as to be rotatable about a rotation shaft 83. Further, a pressing member 86 for driving the collar portion 115 in the left-right direction is provided in the vicinity of the right side portion of the collar portion 115. The flange 115 is always urged to the left by an urging member such as a spring (not shown) provided on the side plate 18 </ b> R, and the other end of the L-shaped link 84 is in contact with the pressing member 86.

  Although not shown, the number of the sound plates 30 in the sound source unit UNT is set to be larger than the total number of white keys 27 and black keys 28 in the keyboard action unit KACT corresponding to the sounding range corresponding to the transposition range. Yes.

  In such a configuration, when the transposing pedal 81 is stepped on, the connecting rod 82 rises and the L-shaped link 84 rotates in the clockwise direction in the drawing to urge the pressing member 86 to the right. Thereby, the pressing member 86 slides the collar part 115 to the right against the urging member (not shown). The keyboard action unit KACT also moves together with the buttock 115. Since the position of the sound source unit UNT is fixed to the side plates 18L and 18R via the support portions 29L and 29R, the correspondence between the sound plate 30 in the sound source unit UNT and the action mechanism 20 in the keyboard action unit KACT is shifted. The same effect as transposition can be obtained. When the transposing pedal 81 is released, the keyboard action unit KACT is returned to the original position together with the collar 115 by the biasing member (not shown), and the key is restored to the original key.

  According to the present embodiment, transposition can be performed in a percussion instrument that produces acoustic sound, and the performance form can be varied. Further, since the keyboard KB and the action mechanism 20 are configured to move together, for example, a shift change mechanism of a grand piano can be applied, and transposition can be enabled with a simple configuration. In addition, since the correspondence between each sound board 30 and the resonance chamber is fixed, good resonance of the sound of each sound board 30 is maintained.

  From the viewpoint of enabling transposition, the relative position between the keyboard action unit KACT and the sound source unit UNT may be configured to be variable. Therefore, the sound source unit UNT may be configured to be slidable instead of the keyboard action unit KACT.

  The operation element for driving the pressing member 86 is operated with a foot such as the transposing pedal 81, but is not limited thereto, and may be operated with a hand. In the present embodiment, the direction of transposition is a direction in which the key is raised, but may be a direction in which the key is lowered.

(Fourth embodiment)
In the third embodiment, the transposition state is configured only while the transposition pedal 81 is depressed. However, in the fourth embodiment of the present invention, the transposition state can be maintained. To do. Therefore, the transposition mechanism is different from that of the third embodiment, and the configuration of the sound source unit UNT, the keyboard action unit KACT, and the like is the same as that of the third embodiment.

  FIG. 14A is a front view of a transposition mechanism in a keyboard instrument configured as a keyboard-type sound board percussion instrument to which the sound board according to the fourth embodiment is applied. FIG. 2A shows the left side portion of the keyboard instrument. FIG. 14B is an inner side view of the left side plate of the keyboard instrument.

  In this transposition mechanism, the configuration of the connecting rod 82, the rotation shaft 83, the L-shaped link 84, the rotation shaft 85, the pressing member 86, and the flange 115 is the same as that of the third embodiment. This is the same except for the difference in length. As shown in FIGS. 14A and 14B, on the inner side surface (right side surface) of the side plate 18L, there is provided a lever 87 for operating with a hand that is rotatable about a rotation shaft 90. . A middle portion of the lever 87 is rotatably connected to the lower end portion of the connecting rod 82 by a rotation shaft 89.

  On the other hand, a stepped positioning stopper portion 88 is formed on the inner side surface (right side surface) of the side plate 18L. The stopper portion 88 has an arc shape along the rotation direction of the lever 87 in a side view (see FIG. 14B), and includes a plurality of steps 88a. The interval between the upper and lower adjacent steps 88a corresponds to the distance for transposition of semitones.

  In such a configuration, the lever 87 is gripped by hand, and the step 88a for locking the lever 87 is changed as desired. For example, when the lever 87 is locked to the upper step 88a, the pressing member 86 is urged to the right via the connecting rod 82 and the L-shaped link 84, and the collar portion 115 slides to the right by a semitone. Moving. When it is desired to lower the tone, the lever 87 may be locked to the lower step 88a.

  According to the present embodiment, not only the same effects as those of the third embodiment can be achieved, but also the transposition can be performed in either the upper or lower direction, and the transposition state can be maintained even if the hand is released.

  Note that the mechanism for transposition may be configured to include both a mechanism for transposing only when the pedal is turned on in the third embodiment and a mechanism for maintaining the transposition state in the fourth embodiment. Good.

  The present invention is also applicable to Glockenspiel.

It is a left view of the keyboard instrument comprised as a keyboard-type sound board percussion instrument to which the sound board which concerns on the 1st Embodiment of this invention is applied. It is a right sectional view showing the internal configuration of the upper half of the keyboard instrument. It is a front view which shows the internal structure of the upper half part of the keyboard instrument. It is a top view which shows the internal structure of the upper half part of the keyboard instrument. It is a top view (figure (a)) of one sound board, and a right view (figure (b)) of the same sound board. It is a front view of a sound source unit. It is sectional drawing which follows the AA line of FIG. It is a bottom view of a sound source unit. Side view (FIG. (A)) of one fastener for holding sound board group collectively, Partial enlarged view (FIG. (B)) of the fastener, and sound plate and fastener corresponding to the high sound region Side view (figure (c)), side view (figure (d)) of the sound plate and fastener corresponding to the midrange, and side view (figure (e) of the sound plate and fastener corresponding to the bass part )). It is the elements on larger scale of the mid range part of the sound source unit shown in FIG. It is the elements on larger scale of the mid range part of the resonance box in the keyboard-type sound board percussion instrument to which the sound board which concerns on the 2nd Embodiment of this invention is applied. It is a fragmentary sectional view showing a modification of a resonance box. It is a front view which shows the internal structure of the keyboard instrument comprised as a keyboard-type sound board percussion instrument to which the sound board which concerns on the 3rd Embodiment of this invention is applied. The front view (FIG. (A)) of the mechanism for the transposition in the keyboard musical instrument comprised as a keyboard-type sound board percussion instrument to which the sound board which concerns on the 4th Embodiment of this invention is applied, The left side of the keyboard musical instrument It is an inner side view (figure (b)) of this side plate.

Explanation of symbols

  30 sound board, 31 abdominal part (longitudinal central part), 32 first mass concentration part, 33 second mass concentration part, 34 first thin part, 35 second thin part, 36 support hole (first supported part) 37 support hole (second supported part), 38 member before processing (long member), KB keyboard, 10, 100 keyboard instrument (keyboard type percussion instrument)

Claims (4)

By virtue of vibration when striking via the action mechanism while supporting the positions serving as nodes in vibration closer to the first and second end portions than the central portion in the longitudinal direction as the first and second supported portions A sound source unit for a keyboard-type soundboard percussion instrument having a plurality of soundboards for at least the low range, each of which generates a musical tone having a unique pitch,
Each of the plurality of sound plates is integrally formed of a single material,
Each of the plurality of sound plates is provided at a position closer to the first and second end portions than the first and second supported portions at the first and second end portions. First and second thin walls provided between the mass concentrating portion, the central portion in the longitudinal direction and the first supported portion, and between the central portion in the longitudinal direction and the second supported portion, respectively. The first and second mass concentrating portions are thicker in the plate thickness direction than the longitudinal central portion and the first and second thin portions, and the first and second thin portions are , Thinner in the plate thickness direction than the central portion in the longitudinal direction,
A sound source unit for a keyboard-type sound board percussion instrument , wherein the thicknesses of the first and second mass concentrating portions vary depending on the sound range, and the lower sound range is thicker . In each of the plurality of sound plates, the first and second mass concentrating portions and the longitudinal center portion protrude to one side in the plate thickness direction with respect to the first and second thin portions. 2. A sound source unit for a keyboard-type sound board percussion instrument according to claim 1 . In each of the plurality of tone plates, said first, second supported portions, according to claim 1, wherein that the engagement portion formed substantially along the width direction of the tone plate Sound generator unit for keyboard-type soundboard percussion instruments. By virtue of vibration when striking via the action mechanism while supporting the positions serving as nodes in vibration closer to the first and second end portions than the central portion in the longitudinal direction as the first and second supported portions A method of manufacturing a sound source unit for a keyboard-type sound board percussion instrument having a plurality of sound boards for at least low frequencies that generate musical sounds of unique pitches,
When manufacturing each of the plurality of sound plates, a long member having a rectangular cross section made of a single material is moved closer to the first and second end portions than the first and second supported portions. By removing by cutting and / or grinding, the first and second mass concentrated portions are formed at the first and second end portions, and between the longitudinal center portion and the first supported portion. And forming the first and second thin portions between the longitudinal center portion and the second supported portion, respectively , in that case, by removing the long member from one direction, The first and second mass concentrating portions remain thicker in the plate thickness direction than the longitudinal central portion and the first and second thin portions, and the first and second thin portions are disposed in the longitudinal central portion. In contrast, the thickness of the first and second mass concentrating portions is made different depending on the sound range, Production method of the sound source unit for keyboard-type tone plate percussion instrument, which comprises forming the Kunar so.

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