Method for Reinforcing Percussion Instrument and Bottom Frame

Abstract

To provide a percussion instrument whose appearance can be improved while a radiation part of a bottom frame is reinforced and to provide a reinforcement method of the bottom frame.SOLUTION: Recesses 24a to 24c formed at a lower face of a radiation part 21 are formed into groove shapes extending in a radial direction from a center part 20 side of a bottom frame 2 toward an outer peripheral side. Thus, rigidity of the bottom frame 2 (radiation part 21) can be secured by the recesses 24a to 24c while formation of ribs is not required or the number of ribs to be formed can be reduced with respect to the radiation part 21 of the bottom frame 2. Since occurrence of shrinkage in the radiation part 21 can be suppressed even if the bottom frame 2 is formed by resin, appearance of a percussion instrument 100 can be improved while the bottom frame 2 is reinforced by the recesses 24a to 24c.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a percussion instrument and a method for reinforcing a bottom frame, and more particularly to a percussion instrument and a method for reinforcing a bottom frame that can improve the appearance while reinforcing the radiation part of the bottom frame.

Background Art

[0002] For example, Patent Document 1 describes a technique of forming a substantially triangular opening in a connecting portion 4c of a sensor frame 4 (bottom frame) that constitutes the bottom surface of a housing of a percussion instrument. Since a plurality of openings are arranged in the circumferential direction of the sensor frame 4, vibrations when the head 5 is struck are easily released to the outside through the openings. Thereby, it is possible to suppress the vibration when striking the head 5 from reverberating inside the housing, and thus the volume generated during such a strike can be reduced.

[0003] On the other hand, when a plurality of openings are formed in the sensor frame 4, the rigidity of the sensor frame 4 is likely to decrease. In order to ensure the rigidity of the sensor frame 4, it is conceivable to form reinforcing ribs in a portion (hereinafter referred to as the "radiation part") that extends radially between the openings arranged in the circumferential direction. As a reinforcing rib, for example, a rib 34 for reinforcing a frame 3 (bottom frame) of Patent Document 2 is exemplified.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, in a configuration where a plurality of ribs are provided on the upper surface of the radiation part, when the bottom frame is molded from resin, there is a problem that sink marks are likely to occur on the lower surface of the radiation part on the side opposite to the ribs, and the appearance is likely to deteriorate.

[0006] The present invention has been made to solve the above-described problems, and an object thereof is to provide a percussion instrument and a method for reinforcing a bottom frame that can improve the appearance while reinforcing the radiation part of the bottom frame.

Means for Solving the Problems

[0007] To achieve this object, a percussion instrument of the present invention includes a head that forms a striking surface, a housing having a cylindrical body portion whose upper end side opening is covered by the head, and a bottom frame that constitutes the bottom surface of the housing. The bottom frame includes the bottom frame a central portion that constitutes the central part, a plurality of radiation parts that radially extend from the central portion to the outer edge side of the housing, and an outer peripheral portion that circumferentially connects the outer edges of the plurality of radiation parts. A recess extending from the central portion side to the outer peripheral portion side is formed on the lower surface of the radiation part. and projections that project downward from both circumferential sides of the concave portion and extend from the central portion side to the outer peripheral portion side is formed.

[0008] A method for reinforcing a bottom frame of the present invention includes a head that forms a striking surface, a housing having a cylindrical body portion whose upper end side opening is covered by the head, and a bottom frame that constitutes the bottom surface of the housing. The bottom frame includes the bottom frame a central portion that constitutes the central part, a plurality of radiation parts that radially extend from the central portion to the outer edge side of the housing, and an outer peripheral portion that circumferentially connects the outer edges of the plurality of radiation parts. A method for reinforcing the bottom frame in a percussion instrument, wherein a recess extending from the central portion side to the outer peripheral portion side and projections that project downward from both circumferential sides of the concave portion and extend from the central portion side to the outer peripheral portion side is formed on the lower surface of the radiation part.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Mode for Carrying Out the Invention

[0010] Hereinafter, preferred embodiments will be described with reference to the accompanying drawings. First, referring to FIG. 1, the overall configuration of the percussion instrument 100 of the first embodiment will be described. FIG. 1 is an exploded perspective view of the percussion instrument 100 of the first embodiment. In FIG. 1, for the sake of simplicity of the drawing, only the protrusion 29 (the part that supports the head sensor 10), which is inside the bottom frame 2 hidden by the support portion 31 of the top frame 3, will be illustrated, which will be described later.

[0011] As shown in FIG. 1, the percussion instrument 100 is an electronic percussion instrument imitating an acoustic drum, and includes a housing 1 that constitutes its main body portion. The housing 1 includes a substantially disk-shaped bottom frame 2 that constitutes its bottom surface, and a top frame 3 that is stacked on the bottom frame 2. The bottom frame 2 and the top frame 3 are frames for supporting the head sensor 10 and the rim sensor 11, and the support structures of these sensors 10 and 11 will be described later with reference to FIGS. 5 and 6.

[0012] The top frame 3 includes a cylindrical body portion 30 and a support portion 31 that supports the rim sensor 11 on the inner peripheral side of the body portion 30, and these portions 30 and 31 are integrally formed using a resin material. In the following description, the direction orthogonal to the axis of the cylindrical body portion 30 is described as the radial direction, and the direction around the axis of the body portion 30 is described as the circumferential direction for explanation.

[0013] The opening portion on the upper surface side of the body portion 30 is covered by the membrane-like head 4, so that the upper surface of the head 4 becomes the striking surface of the percussion instrument 100. The head 4 is formed in a disc shape using a mesh knitted from synthetic fibers, and an annular head frame 40 is fixed to the outer edge of the head 4.

[0014] The head frame 40 is formed using a resin material, and the head 4 and the head frame 40 are integrally formed by die molding. Note that the head frame 40 may be formed using a material other than resin (for example, metal or wood), and the head frame 40 may be joined to the head 4 by adhesion or the like.

[0015] The head 4 is attached to the housing 1 by a hoop 6 together with the annular rim 5. In this attached state, the outer edge portion of the head 4 is surrounded by the rim 5 over the entire circumference. The rim 5 is a member for performing a rim shot in which the performer strikes the head 4 and the rim 5 simultaneously, or a rim-only shot in which only the rim 5 is struck. The rim 5 includes an annular struck portion 50 that receives a strike from the performer, and a substantially rectangular parallelepiped-shaped clamped portion 51 formed on the outer peripheral surface of the struck portion 50, and these portions 50 and 51 are integrally formed using a resin material (such as rubber or elastomer) that is softer than the hoop 6.

[0016] The clamped parts 51 are formed at equal intervals (or unequal intervals) in the circumferential direction of the struck part 50 (in this embodiment, at 16 positions). On the inner circumferential surface of the hoop 6, a plurality of accommodating parts 60 are formed at positions corresponding to the clamped parts 51. The accommodating part 60 is a recess having a shape corresponding to the clamped part 51. When the rim 5 is attached to the upper surface of the head 4, the clamped part 51 is accommodated in the accommodating part 60. Since a known configuration can be adopted for the attachment structure of this rim 5, a detailed description thereof is omitted. As a known configuration, the attachment structure of the rim 5 disclosed in Japanese Patent Application Laid-Open No. 2019-148623 is exemplified.

[0017] In the hoop 6, through holes 61 (see Fig. 4(a)) for inserting tension bolts B1 are formed at equal intervals in the circumferential direction. In the housing 1, a plurality of lugs 7 (in this embodiment, at 6 positions) for fastening (threading) the tension bolts B1 are provided at equal intervals in the circumferential direction.

[0018] The lug 7 includes a fastening part 70 disposed on the outer peripheral side of the body part 30 of the top frame 3. In the fastening part 70, a female screw hole 70a extending vertically is formed. While fitting the clamped part 51 of the rim 5 into the accommodating part 60 of the hoop 6 and hooking the head frame 40 of the head 4 on the hoop 6, tension is applied to the head 4 by fastening the tension bolt B1 to the female screw hole 70a of the lug 7. Next, the detailed configuration of the housing 1 will be described with reference to Figs. 2 and 3.

[0019] Fig. 2(a) is a perspective view of the bottom frame 2 viewed from the lower surface side, and Fig. 2(b) is a perspective view of the lug 7 and the anti-loosening member 8. Fig. 3 is an exploded perspective view of the housing 1 of the percussion instrument 100.

[0020] As shown in Figs. 2 and 3, the bottom frame 2 of the housing 1 includes a circular (substantially disk-shaped) central part 20 forming the central portion thereof, a plurality of radial parts 21 radially extending from the central part 20, and an annular outer peripheral part 22 connecting the outer edges of these plurality of radial parts 21. These parts 20 to 22 are integrally formed using a resin material.

[0021] The central part 20 is a part provided in a region including the axis of the body part 30. Note that a plurality of recesses (plate-like ribs partitioning the central part 20) and electronic components such as substrates are provided in the central part 20. However, in FIG. 2, illustration of these recesses and electronic components is omitted for simplicity of the drawing.

[0022] The radial part 21 extends along the radial direction from the central part 20 toward the outer peripheral side. Since a plurality (six in this embodiment) of the radial parts 21 are arranged at equal intervals in the circumferential direction, a plurality (six in this embodiment) of substantially triangular sound emission holes 23 penetrating the bottom frame 2 vertically are formed between the plurality of radial parts 21.

[0023] Although a configuration for forming such sound emission holes 23 is known (for example, Japanese Patent Application Laid-Open No. 2004-198657), when a plurality of sound emission holes 23 are formed in the bottom frame 2, while the vibration when the head 4 (see FIG. 1) is struck is easily emitted to the outside through the sound emission holes 23, the rigidity of the bottom frame 2 is likely to decrease. In contrast, in this embodiment, recesses 24a to 24c for reinforcing the bottom frame 2 are formed in the radial part 21 (see FIG. 2). These recesses 24a to 24c are parts for fixing the lug 7 (see FIG. 2(b)).

[0024] The recesses 24a to 24c formed on the lower surface of the radial part 21 are formed in a groove shape extending from the central part 20 side to the outer peripheral side (along the radial direction) of the bottom frame 2. Thereby, it is possible to eliminate the formation of ribs (for example, the rib 34 in Japanese Patent Application Laid-Open No. 2021-105702) like the prior art or reduce the number of ribs to be formed, while ensuring the rigidity of the bottom frame 2 (radial part 21) by the recesses 24a to 24c. Therefore, even when the bottom frame 2 is molded from resin, it is possible to suppress the occurrence of sink marks in the radial part 21, so that the appearance of the percussion instrument 100 can be improved while reinforcing the bottom frame 2 with the recesses 24a to 24c.

[0025] The recess 24a is a recess extending from the central portion 20 side toward the outer peripheral side, and the recess 24b is a recess formed so as to be continuous with the end portion on the outer peripheral side of the recess 24a. These recesses 24a and 24b are formed in a region including the center of the radial portion 21 in the circumferential direction. In the region where the recess 24a is formed, the width dimension of the radial portion 21 in the circumferential direction (the thickness of the radial portion 21 in the circumferential direction) is gradually formed smaller as it approaches the recess 24b. Further, in the region where the recess 24b (recess 24c) is formed, the width dimension of the radial portion 21 in the circumferential direction is gradually formed larger as it goes toward the outer peripheral side.

[0026] On the other hand, the width dimension of the recess 24a in the circumferential direction (the opening width of the recess 24a in the circumferential direction) is also formed gradually smaller as it approaches the recess 24b, and the width dimension of the recess 24b in the same direction is also formed gradually larger as it goes toward the outer peripheral side. Thereby, the rigidity of the radial portion 21 can be uniformly increased in its longitudinal direction (the region where each of the recesses 24a and 24b is formed). Further, by changing the width dimensions of the recesses 24a and 24b in the same manner according to the change in the width dimension of the radial portion 21, the appearance of the percussion instrument 100 can be improved.

[0027] The bottom surface (the surface facing downward) of the recess 24a is a flat surface that slopes downward toward the outer peripheral side (see Fig. 4(a)), and the bottom surface 21a of the radial portion 21 is a curved surface that gradually slopes upward toward the outer peripheral side (see Fig. 4(a)). Therefore, the depth of the recess 24a with respect to the bottom surface 21a of the radial portion 21 is gradually formed shallower from the central portion 20 side toward the outer peripheral side. Hereinafter, the depth of the recesses 24a to 24c with respect to the bottom surface 21a of the radial portion 21 will be simply described as "the depth of the recess 24a" and the like for explanation.

[0028] The depth of the inner edge portion (the end portion on the inner peripheral side) of the recess 24b is formed deeper than the depth of the outer edge portion (the end portion on the outer peripheral side) of the recess 24a, and a step is formed at the boundary portion (the connecting portion) between these recesses 24a and 24b. By forming such a step, the rigidity of the radial portion 21 can be effectively improved.

[0029] The bottom surface of the recess 24b is composed of a horizontal surface extending from its inner edge toward the outer edge side, and an inclined surface connected to the outer edge of the horizontal surface and rising and inclining toward the outer peripheral side. The depth of this recess 24b also gradually becomes shallower from the inner peripheral side to the outer peripheral side.

[0030] The inner edge of the recess 24c is located on the outer peripheral side of the inner edge of the recess 24b, and the recess 24c is formed in a region including the circumferential center of the bottom surface of the recess 24b. That is, since the recess 24c is a groove that is recessed deeper than the bottom surface of the recess 24b, the rigidity of the radial portion 21 can be more effectively improved by the step formed by these recesses 24b and 24c.

[0031] Both the recess 24b and the recess 24c extend to the outer edge of the bottom frame 2, and the lugs 7 are fixed using these respective recesses 24b and 24c.

[0032] The lug 7 includes a lower surface portion 71 that extends from the lower end of the fastening portion 70 toward the inner peripheral side and constitutes the lower surface of the lug 7, and a fixing portion 72 that rises from the lower surface portion 71 and is fixed to the bottom frame 2. These respective portions 70 to 72 are integrally formed using metal.

[0033] The fastening portion 70 is formed with a cavity 70c having an opening 70b on the inner peripheral side (inner peripheral surface) of the fastening portion 70, and the above-described tapping hole 70a communicates with this cavity 70c. The lower surface portion 71 of the lug 7 is formed in a plate shape that extends from the lower edge of the fastening portion 70 (cavity 70c) toward the inner peripheral side, and the fixing portion 72 protrudes upward from a region including the center of the lower surface portion 71 in the circumferential direction. In other words, the lower surface portion 71 projects in a flange shape from the side surface (surface facing the circumferential direction) and the lower end of the inner peripheral surface of the fixing portion 72.

[0034] A detent 8 for suppressing loosening of the tension bolt B1 (see FIG. 1) is inserted into the cavity 70c of the fastening portion 70. The detent 8 includes a main body portion 80 having a shape (substantially semi-cylindrical shape) corresponding to the internal space of the cavity 70c of the fastening portion 70, and a pair of leg portions 81 that project downward from the lower surface of the main body portion 80. These respective portions 80 and 81 are integrally formed using a resin material.

[0035] Since the main body portion 80 of the anti-loosening member 8 is formed with a female screw hole 82 extending vertically, with the anti-loosening member 8 inserted into the cavity 70c, the tension bolt B1 is fastened to the female screw hole 70a of the fastening portion 70, so that the tension bolt B1 is also fastened to the female screw hole 82 of the anti-loosening member 8 (for the state where the tension bolt B1 is fastened to the anti-loosening member 8, refer to FIG. 4(a)).

[0036] The fixing portion 72 is formed in a substantially rectangular parallelepiped shape in which the dimension in the radial direction is longer than the dimension in the circumferential direction, and the substantially rectangular parallelepiped-shaped fixing portion 72 extending in the radial direction extends into the cavity 70c of the fastening portion 70. In a state where the main body portion 80 of the anti-loosening member 8 is inserted into the cavity 70c, a pair of leg portions 81 spaced apart in the circumferential direction are arranged so as to sandwich the fixing portion 72. Therefore, even when the anti-loosening member 8 tries to rotate when the tension bolt B1 is fastened to the female screw hole 82, the rotation is restricted by the engagement between the pair of leg portions 81 and the fixing portion 72.

[0037] In this way, by hooking the pair of leg portions 81 on the fixing portion 72 extending to the inside of the cavity 70c, the rotation of the anti-loosening member 8 can be restricted using the fixing portion 72. Further, with the pair of leg portions 81 hooked on the fixing portion 72 (the main body portion 80 placed on the fixing portion 72), by sliding the anti-loosening member 8 toward the cavity 70c side, the insertion of the anti-loosening member 8 into the cavity 70c can be guided by the fixing portion 72. Therefore, the workability of the assembling operation of the lug 7 can be improved.

[0038] The outer shape (upper surface and side surface) of the lower surface portion 71 is formed in a shape that coincides with the bottom surface and side surface (the surface surrounding the bottom surface) of the above-described recess 24b, and similarly, the outer shape of the fixing portion 72 is formed in a shape that coincides with the recess 24c. A pair of female screw holes 73, 74 arranged in the radial direction (the longitudinal direction of the fixing portion 72) are formed in the fixing portion 72 of the lug 7. These pair of female screw holes 73, 74 are for fixing the lug 7 to the lower surface of the bottom frame 2. When fixing the lug 7 to the bottom frame 2, the fixing portion 72 and the lower surface portion 71 of the lug 7 are fitted into the recess 24b and the recess 24c.

[0039] In a state where the lugs 7 are fitted into the recesses 24b and 24c, the recesses 24b and 24c are covered by the lugs 7, while the recess 24a is exposed on the lower surface side of the bottom frame 2 without being covered by the lugs 7. In this case, for example, if a rib (a plate-like wall extending in the circumferential direction) that divides the recess 24a is formed, although the rigidity of the radiation part 21 is increased, the rib is exposed on the lower surface side of the percussion instrument 100 and the appearance deteriorates.

[0040] On the other hand, in the present embodiment, the recess 24a is formed in a single groove shape that is continuous in the radial direction. That is, the radiation part 21 is reinforced by the step formed by forming the respective recesses 24a to 24c without forming the rib as described above in the recess 24a. Thereby, while ensuring the rigidity of the bottom frame 2, the appearance of the percussion instrument 100 can be improved.

[0041] Next, with reference to FIGS. 3 and 4, the detailed configuration of the housing 1 including the attachment structure of the lugs 7 will be described. FIG. 4(a) is a partially enlarged cross-sectional view of the percussion instrument 100 taken along line IVa-IVa of FIG. 3, and FIG. 4(b) is a cross-sectional view of the radiation part 21 taken along line IVb-IVb of FIG. 4(a). In FIG. 4(a), the end face of the cut part cut in a plane including the axis of the body part 30 and the tension bolt B1 is shown, and in FIG. 4(b), the end face of the cut part of the radiation part 21 is shown. In FIG. 4(a), the bottom surface 21a of the radiation part 21 located behind (the back side in the direction perpendicular to the paper surface) the cut surface is shown by a solid line.

[0042] As shown in FIGS. 3 and 4, a pair of through holes 25 and 26 arranged in the radial direction are formed at positions corresponding to the screw holes 73 and 74 of the lugs 7 in the radiation part 21 and the outer peripheral part 22 of the bottom frame 2. This pair of through holes 25 and 26 penetrate the radiation part 21 and the outer peripheral part 22 vertically and are connected to the bottom surface of the recess 24c. The pair of through holes 25 and 26 are holes for screwing the lugs 7 with the fixing bolts B2, and the reinforcing frame 9 is also clamped together with the fixing bolts B2. The reinforcing frame 9 is a frame that forms the skeleton of the housing 1 together with the bottom frame 2 and the top frame 3.

[0043] The reinforcing frame 9 includes an annular portion 90 (see FIG. 3) that is overlapped with the outer peripheral portion 22 of the bottom frame 2, and a protruding portion 91 that protrudes from the annular portion 90 toward the inner peripheral side. Each of these portions 90 and 91 is integrally formed using a metal plate.

[0044] A pair of through holes 92 and 93 (see FIG. 4(a)) are formed in the annular portion 90 and the protruding portion 91 of the reinforcing frame 9 at positions corresponding to the through holes 25 and 26 of the bottom frame 2. By fastening the fixing bolts B2 inserted into the through holes 25, 26, 92, and 93 of the bottom frame 2 and the reinforcing frame 9 to the tapped holes 73 and 74 of the lug 7, the bottom frame 2 and the reinforcing frame 9 are fastened together to the lug 7.

[0045] Thus, in this embodiment, the reinforcing frame 9 (annular portion 90) formed of a material (metal plate) harder than the bottom frame 2 is fixed to the outer peripheral portion 22 of the bottom frame 2. Since the reinforcing frame 9 includes a protruding portion 91 that protrudes toward the inner peripheral side and is fixed (screwed) to the radial portion 21, the rigidity of the radial portion 21 can be effectively increased by the protruding portion 91.

[0046] Also, the fixing portion 72 of the lug 7 extends to the inner peripheral side from the outer peripheral surface of the body portion 30 (housing 1) and is fixed to the lower surface of the bottom frame 2 (housing 1) by the fixing bolt B2. Therefore, the tension bolt B1 (see FIG. 4(a)) for applying tension to the head 4 and the fixing bolt B2 for fixing the lug 7 to the bottom frame 2 can be arranged with a radial shift. As a result, compared with the structure in the prior art (for example, Japanese Patent Application Laid-Open No. 2014-130373) in which a bolt for fixing a lug to a housing is fastened from below the lug, the dimension of the lug 7 in the vertical direction can be reduced. Therefore, the bottom frame 2 (housing 1) can be made thinner.

[0047] Also, since the fixing bolt B2 inserted into the bottom frame 2 (reinforcing frame 9) from the upper side is fastened to the fixing portion 72, it is possible to suppress the head of the fixing bolt B2 from being exposed on the lower surface side of the lug 7. Therefore, the appearance of the percussion instrument 100 can be improved.

[0048] Here, since the lug 7 (fixing portion 72) is screwed to the lower surface of the bottom frame 2 by the fixing bolt B2, the load when fastening the tension bolt B1 to the fastening portion 70 acts on the lower surface of the bottom frame 2 (housing 1) via the fixing bolt B2.

[0049] More specifically, assuming that the contact portion between the outer edge of the bottom frame 2 (the bottom surface of the recess 24c) and the fixing portion 72 of the lug 7 is the contact point P (see Fig. 4(a)), when the tension bolt B1 is fastened to the fastening portion 70, a moment is generated that pulls the fastening portion 70 upward around the contact point P (fulcrum), while pulling the fixing portion 72 and the fixing bolt B2 downward. As a result, a load via the fixing bolt B2 acts on the lower surface of the bottom frame 2 (housing 1).

[0050] In contrast, in this embodiment, since the lug 7 (fixing portion 72) is screwed to the lower surface of the bottom frame 2 by two fixing bolts B2 arranged in the radial direction, the load acting on the bottom frame 2 when fastening the tension bolt B1 can be dispersed to two locations in the radial direction. Thereby, while thinning the bottom frame 2, the durability of the bottom frame 2 (housing 1) against the load when fastening the tension bolt B can be ensured.

[0051] Also, as described above, the annular reinforcing frame 9 made of a material harder than the bottom frame 2 is overlaid on the bottom frame 2, and the respective frames 2, 9 and the fixing portion 72 are fastened together by the fixing bolt B2. Thereby, the vicinity of the fixing bolt B2 where the load when fastening the tension bolt B1 acts most can be effectively reinforced by the reinforcing frame 9. Also by this, while thinning the bottom frame 2, the durability of the bottom frame 2 (housing 1) against the load when fastening the tension bolt B can be ensured.

[0052] In addition, since the fastening part 70 is provided on the outer peripheral side (positions arranged in the radial direction) of the radiation part 21 in which the concave parts 24a to 24c are formed, it is possible to receive the load at the time of fastening the tension bolt B1 in a region where the rigidity of the bottom frame 2 is relatively high. Therefore, while thinning the bottom frame 2, it is possible to ensure the durability of the bottom frame 2 (housing 1) against the load at the time of fastening the tension bolt B.

[0053] Further, since the lugs 7 (bottom surface part 71 and fixing part 72) are fitted into the concave parts 24b and 24c formed on the lower surface of the bottom frame 2 (housing 1), the rigidity of the bottom frame 2 (housing 1) around the fixing part 72 can be effectively improved by the concave parts 24b and 24c. Furthermore, by fitting the lugs 7 into the concave parts 24b and 24c, the step formed on the lower surface side of the bottom frame 2 can be filled with the lugs 7, so that the appearance of the percussion instrument 100 can be improved.

[0054] As described above, the bottom frame 2 and the reinforcing frame 9 are jointly fastened to the lug 7 by the fixing bolt B2, and the bottom frame 2 and the top frame 3 are screwed to the reinforcing frame 9 by the fixing bolts B3 and B4.

[0055] Specifically, a pair of female screw holes 94 and 95 arranged in the radial direction are formed between the through holes 92 and 93 of the reinforcing frame 9. Further, a through hole 27 is formed at a position corresponding to the female screw hole 94 in the radiation part 21 of the bottom frame 2, and a through hole 32 (see Fig. 4(a)) is formed at a position corresponding to the female screw hole 95 in the support part 31 (annular part 31c described later) of the top frame 3.

[0056] In the female screw hole 94 of the reinforcing frame 9, a fixing bolt B3 inserted into the through hole 27 from the lower side of the bottom frame 2 (radiating portion 21) is fastened, and in the female screw hole 95, a fixing bolt B4 inserted into the through hole 32 from the upper side of the top frame 3 (support portion 31) is fastened. These fixing bolts B3 and B4 are arranged side by side in the radial direction together with the pair of fixing bolts B2. Thereby, in the vicinity of the fixing bolt B2 where the load at the time of fastening the tension bolt B1 acts most, the housing 1 composed of the bottom frame 2, the top frame 3, and the reinforcing frame 9 can be effectively reinforced. Therefore, while thinning the housing 1, the durability of the housing 1 against the load at the time of fastening the tension bolt B1 can be ensured.

[0057] As described above, in this embodiment, since the bottom frame 2 and the top frame 3 are screwed to the reinforcing frame 9 formed using a metal plate, the function of ensuring the rigidity of the housing 1 can be mainly borne by the reinforcing frame 9, and accordingly, the thicknesses of the bottom frame 2 and the top frame 3 can be reduced. Therefore, while ensuring the rigidity of the housing 1, the housing 1 can be thinned.

[0058] Next, with reference to FIGS. 3 to 5, a configuration for detecting vibrations at the time of striking the head 4 and the rim 5 by the head sensor 10 and the rim sensor 11 will be described. FIG. 5 is a partially enlarged cross-sectional view of the percussion instrument 100 taken along line V-V of FIG. 3. In FIG. 5, the end face of the cut portion of the percussion instrument 100 cut along a plane including the axis of the body portion 30 and the protrusion portion 29 is shown, but one first connection portion 31b (see FIG. 3) located behind the cut surface (the back side in the direction perpendicular to the paper surface) is schematically shown.

[0059] First, the striking of the rim 5 will be described. As shown in FIG. 4(a), since the rim 5 is supported via the head 4 on the upper side of the body portion 30 of the top frame 3, the vibration when the rim 5 is struck is mainly transmitted to the support portion 31 via the body portion 30.

[0060] In the following description, among the plate-shaped support portion 31, the portion that supports the rim sensor 11 in the region including the axis of the body portion 30 is the central portion 31a, the portion that extends radially from the central portion 31a is the first connection portion 31b, and the portion that annularly connects the outer edges of a plurality (six in this embodiment) of the first connection portions 31b arranged in the circumferential direction is described as the annular portion 31c (see FIG. 3).

[0061] The first connection portion 31b connects the central portion 31a and the annular portion 31c of the top frame 3 along the radial direction (linearly). When the rim 5 is struck, the vibration is transmitted to the rim sensor 11 through the body portion 30, the annular portion 31c, the first connection portion 31b, and the central portion 31a. The rim sensor 11 is a disc-shaped piezoelectric element and is adhered to the central portion 31a via a cushioning double-sided tape (see FIG. 5).

[0062] When vibration is detected by the rim sensor 11, a musical sound signal based on the detection result is generated by a sound source (not shown), and the musical sound signal is output to an amplifier and a speaker (both not shown), whereby electronic music is emitted from the speaker (the same applies to the head sensor 10 described later).

[0063] The support portion 31 (the frame composed of the central portion 31a, the first connection portion 31b, and the annular portion 31c) that supports the rim sensor 11 is connected to the body portion 30 over the entire circumference in the circumferential direction (via the annular portion 31c). Thereby, no matter which position of the rim 5 in the circumferential direction is struck, the vibration caused by the strike is easily transmitted to the rim sensor 11 of the central portion 31a via the first connection portion 31b.

[0064] Also, although the details of the support structure of the head sensor 10 by the bottom frame 2 (see FIG. 5) will be described later, the bottom frame 2 that supports the head sensor 10 and the top frame 3 that supports the rim sensor 11 are separate parts. Therefore, it is possible to suppress the vibration when the rim 5 is struck from being erroneously detected by the head sensor 10 and the vibration when the head 4 is struck from being erroneously detected by the rim sensor 11, so that the detection accuracy of the strike on the rim 5 can be improved.

[0065] Further, since a plurality of the first connection portions 31b that connect the body portion 30 (the annular portion 31c) and the central portion 31a are arranged in the circumferential direction, through holes are formed between the first connection portions 31b. By forming such through holes, it is possible to suppress the vibration at the time of hitting the head 4 from resonating in the support portion 31. Further, while forming through holes between the first connection portions 31b of the support portion 31, by also forming sound release holes 23 in the bottom frame 2, the vibration at the time of hitting the head 4 is easily released to the outside through the through holes of the support portion 31 and the sound release holes 23 of the bottom frame 2. Therefore, the volume generated at the time of hitting the head 4 can be reduced.

[0066] Also, since the body portion 30 is integrally formed with the support portion 31 including the first connection portion 31b, the vibration at the time of hitting the rim 5 is easily transmitted from the body portion 30 to the first connection portion 31b. Thereby, since the vibration at the time of hitting the rim 5 is easily detected by the rim sensor 11 of the central portion 31a, the detection accuracy of the hit on the rim 5 can be improved.

[0067] Here, as described above, the bottom frame 2 is screwed to the lower surface of the top frame 3 via the reinforcing frame 9 (by the fixing bolts B2 to B4). However, for example, it is also possible to screw the bottom frame 2 and the reinforcing frame 9 to the first connection portion 31b. However, if the bottom frame 2 and the reinforcing frame 9 are screwed to the first connection portion 31b, the vibration (flexure) of the first connection portion 31b is inhibited by the screwed portion.

[0068] On the other hand, in the present embodiment, the bottom frame 2 and the reinforcing frame 9 are screwed to the lower surface of the top frame 3 on the outer peripheral side of the first connection portion 31b (by the fixing bolt B4), so that it is possible to suppress the screwed portion from inhibiting the vibration of the first connection portion 31b. Therefore, the first connection portion 31b easily vibrates at the time of hitting the rim 5, and thus the vibration at the time of hitting the rim 5 is easily detected by the rim sensor 11.

[0069] Also, as in the percussion instrument 200 (see FIG. 6) of the second embodiment described later, it is possible to directly screw the top frame 3 to the bottom frame 202 by omitting the reinforcing frame 9. However, in the structure in which the resin frames 202 and 3 are screwed together, the rigidity of the screwed portion becomes low. When the rigidity of the screwed portion is low, the bottom frame 2 is likely to vibrate due to the impact of hitting the rim 5, or the vibration is attenuated at the screwed portion with low rigidity. Therefore, the vibration when hitting the rim 5 cannot be efficiently transmitted to the rim sensor 11 via the first connecting portion 31b.

[0070] On the other hand, in the present embodiment, since the reinforcing frame 9 harder than the bottom frame 2 and the top frame 3 is screwed between the bottom frame 2 and the top frame 3, the rigidity of the connecting portions of the frames 2, 3, and 9 can be increased. As a result, it is possible to suppress the bottom frame 2 from vibrating due to the impact of hitting the rim 5 and the vibration from being attenuated at the connecting portions of the frames 2, 3, and 9. Therefore, the vibration when hitting the rim 5 can be efficiently transmitted to the rim sensor 11 via the first connecting portion 31b.

[0071] Also, a second connecting portion 31d (see FIG. 3) branching from the first connecting portion 31b is formed in the support portion 31. The second connecting portion 31d extends linearly at an angle inclined with respect to the radial direction, and the substantially central portion of the first connecting portion 31b (the portion closer to the center than both ends of the first connecting portion 31b in the radial direction) and the annular portion 31c are connected by the second connecting portion 31d.

[0072] In this way, by connecting the second connecting portion 31d branching from the first connecting portion 31b to the body portion 30 (annular portion 31c) on the outer peripheral side of the central portion 31a, the transmission path of vibration connecting from the body portion 30 to the first connecting portion 31b can be increased by the second connecting portion 31d. Therefore, the vibration when hitting the rim 5 is likely to be transmitted to the rim sensor 11, so the detection accuracy of hitting the rim 5 can be improved.

[0073] In addition, in the present embodiment, for each of the first connection portions 31b arranged in the circumferential direction, two second connection portions 31d are symmetrically shaped with the first connection portion 31b interposed therebetween. That is, in a top view, the two second connection portions 31d are line-symmetric with respect to a straight line along the radial direction (first connection portion 31b) as the target axis, but the two second connection portions 31d may be formed asymmetrically.

[0074] Since the second connection portions 31d are formed on both circumferential sides of each first connection portion 31b (two second connection portions 31d branch from each first connection portion 31b), in the circumferential direction of the top frame 3, there are a region where the first connection portion 31b and the second connection portion 31d are adjacent to each other and a region where the second connection portions 31d are adjacent to each other.

[0075] The second connection portions 31d adjacent to each other in the circumferential direction are connected in the circumferential direction by a third connection portion 31e. The third connection portion 31e extends in an arc shape along the circumferential direction and connects the substantially central portions of the second connection portions 31d (portions closer to the center than both ends of the second connection portion 31d in the radial direction).

[0076] By connecting the second connection portions 31d adjacent to each other in the circumferential direction with the third connection portion 31e, the transmission path of vibration leading from the body portion 30 to the first connection portion 31b can be further increased by the third connection portion 31e. Therefore, the vibration at the time of hitting the rim 5 is easily transmitted to the rim sensor 11, so that the detection accuracy of hitting the rim 5 can be improved.

[0077] Each of the first connection portions 31b arranged in the circumferential direction is formed at a position overlapping with the sound emission hole 23 (see FIG. 3) of the bottom frame 2 in the vertical direction. That is, although not shown, when the bottom frame 2 is viewed from below, the first connection portion 31b is arranged in a region including the circumferential center of the sound emission hole 23. On the other hand, the two second connection portions 31d branching from the first connection portion 31b are arranged along the edge of the sound emission hole 23 (radiating portion 21) extending in the radial direction. By forming the connection portions 31b and 31d in a shape corresponding to the sound emission hole 23 (radiating portion 21) in this way, the appearance of the percussion instrument 100 when viewed from below can be improved.

[0078] Here, when aiming to increase the vibration transmission path from the body part 30 (annular part 31c) toward the central part 31a, for example, a configuration where one end of the second connection part 31d is connected to the central part 31a instead of the first connection part 31b, or a configuration where a connection part connecting the third connection part 31e and the central part 31a is further provided can be adopted. However, in such a configuration, although the vibration transmission path can be increased, the points that restrain the vibration of the central part 31a itself (the vertical displacement of the central part 31a accompanying the deflection of the first connection part 31b) increase. Therefore, as a result, the sensitivity of the rim sensor 11 to impacts on the rim 5 tends to decrease.

[0079] In contrast, in the present embodiment, only the first connection part 31b extending in the radial direction is connected to the central part 31a. Thereby, while the points that restrain the vibration of the central part 31a itself can be reduced, a large number of vibration transmission paths can be formed in the vicinity of the body part 30 (annular part 31c). Therefore, the sensitivity of the rim sensor 11 to impacts on the rim 5 can be improved.

[0080] Next, the impact on the head 4 will be described. First, the support structure of the head sensor 10 will be described. As described above, recesses 24a to 24c are formed in the bottom surface 21a of the radial part 21 of the bottom frame 2. As these recesses 24a to 24c are formed, convex parts are formed on the upper surface side of the radial part 21. In the following description, the configuration of the convex part 28 corresponding to the recess 24a will be described.

[0081] As shown in FIGS. 4 and 5, in the region where the recess 24a is formed, since the radial part 21 is formed in a plate shape with a substantially constant thickness, a convex part 28 corresponding to the recess 24a is formed on the upper surface side of the radial part 21. More specifically, the radial part 21 includes a first plate 21b whose lower surface is the bottom surface of the recess 24a (the upper surface is the upper surface of the convex part 28), and a pair of second plates 21c extend downward from both ends in the circumferential direction (the left - right direction in FIG. 4(b)) of the first plate 21b. The inner edge (the right - hand end in FIG. 4(a)) of the space surrounded by the first plate 21b and the second plates 21c is closed by a third plate 21d, and the recess 24a is formed by these first to third plates 21b to 21d.

[0082] Further, a pair of fourth plates 21e (see FIG. 4(b)) extend radially outward (in a direction away from each other) from the lower ends of the pair of second plates 21c, and a fifth plate 21f extends upward from the radially outer ends (the side opposite to the second plates 21c) of the pair of fourth plates 21e. The fourth plates 21e are the parts that constitute the bottom surface 21a of the radiation part 21, and the fifth plate 21f is the part that constitutes the side surface of the radiation part 21 facing the circumferential direction.

[0083] Thus, as the concave portion 24a is formed by the first to third plates 21b to 21d of the radiation part 21, a convex portion 28 is formed on the upper surface side of the radiation part 21, and a pair of protruding portions 29 rising in a columnar shape are integrally formed on the upper surface of this convex portion 28 (see FIGS. 3 and 5).

[0084] As shown in FIG. 5, the protruding portion 29 protrudes upward from the first connection portion 31b through between each first connection portion 31b (the part on the inner circumferential side than the second connection portion 31d), and the head sensor 10 is attached to the upper surface of this protruding portion 29 via the plate 12.

[0085] Thus, in this embodiment, the head sensor 10 is attached to the protruding portion 29 extending above the top frame 3 through between each first connection portion 31b. Thereby, while enabling the top frame 3 to be stacked on the bottom frame 2 that supports the head sensor 10 (connecting the support portion 31 that supports the rim sensor 11 to the body portion 30 above the bottom frame 2), the head sensor 10 can be brought into contact with the head 4.

[0086] By stacking the top frame 3 that supports the rim sensor 11 on the bottom frame 2 that supports the head sensor 10, the vibration transmission path from the rim 5 to the rim sensor 11 can be shortened, while the vibration transmission path from the rim 5 to the head sensor 10 can be lengthened. Therefore, the vibration at the time of impact on the rim 5 is likely to be detected by the rim sensor 11, and the vibration at the time of impact on the rim 5 can be suppressed from being erroneously detected by the head sensor 10. Therefore, the impact on the rim 5 can be detected accurately.

[0087] The pair of protrusions 29 are arranged along the radial direction. Taking a pair of protrusions 29 as a set, a total of 4 sets of protrusions 29 are provided at equal intervals in the circumferential direction (see Fig. 3). That is, in the present embodiment, the vibration during the impact on the head 4 is detected by the four head sensors 10.

[0088] Threaded holes 29a are formed in each of the pair of protrusions 29, and through holes 12a are formed in the plate 12 at positions corresponding to the threaded holes 29a. By fastening the fixing bolts B5 inserted into the through holes 12a to the threaded holes 29a of the protrusions 29, the plate 12 is fixed (supported) on the upper surface of the protrusions 29.

[0089] A disc-shaped sensor 10b (piezoelectric element) is adhered to the upper surface of the plate 12 by a cushioning double-sided tape 10a, and a cushion 10c is adhered to the upper surface of this sensor 10b. The head sensor 10 is constituted by these double-sided tape 10a, sensor 10b, and cushion 10c.

[0090] The cushion 10c is a frustum-shaped cushioning material formed using a flexible material such as sponge, rubber, or thermoplastic elastomer, and the upper end of the cushion 10c contacts the lower surface of the head 4.

[0091] The plate 12 is a substantially rectangular (substantially elliptical) plate whose dimension in the radial direction (its longitudinal direction) is larger than its dimension in the circumferential direction (width direction), and one end side in its longitudinal direction (hereinafter referred to as the "base end side") is supported by the protrusion 29. On the other hand, the other end side in the longitudinal direction of the plate 12 (hereinafter referred to as the "tip end side") is not supported by the bottom frame 2.

[0092] That is, since the head sensor 10 is supported in a cantilevered state on the plate 12, when the head 4 is struck in the vicinity directly above the cushion 10c, the plate 12 deforms by bending. Since the bending of this plate 12 can absorb the impact at the time of striking the head 4, when the vicinity directly above the head sensor 10 (cushion 10c) is struck, it is possible to suppress the output value of the sensor 10b from becoming extremely large (a so-called hot spot occurs). Thereby, it is possible to suppress variations in the sensitivity of the sensor 10b between the hitting area close to directly above the head sensor 10 and the hitting area far from the head sensor 10. Therefore, the sensitivity distribution of the head sensor 10 with respect to the impact on the head 4 can be made uniform.

[0093] Here, for example, if the plate 12 (head sensor 10) is supported in a cantilevered manner in a region of relatively low rigidity in the bottom frame 2, the impact due to a strike in the vicinity directly above the head sensor 10 is more likely to be absorbed by the bending of the bottom frame 2. In the case of such a configuration, due to errors in the thickness (rigidity) during the molding of the bottom frame 2, etc., the bottom frame 2 may bend more than necessary and the impact force may be absorbed excessively, and an error is likely to occur in the sensitivity of the head sensor 10 (it becomes difficult to obtain the target output value).

[0094] In contrast, in the present embodiment, by forming the concave portion 24a on the lower surface of the bottom frame 2 (radiating portion 21), the rigidity of the portion supporting the head sensor 10 is increased. That is, on the upper surface side of the bottom frame 2 (radiating portion 21), a convex portion 28 having a shape corresponding to the concave portion 24a is formed, and the plate 12 is attached to the protruding portion 29 provided on this convex portion 28. Therefore, the head sensor 10 is supported in a region of relatively high rigidity of the bottom frame 2. Thereby, it is possible to suppress the bottom frame 2 (convex portion 28) from bending due to the impact of a strike in the vicinity directly above the head sensor 10.

[0095] In addition, since the plate 12 is fixed to a pair of protrusions 29 arranged along the longitudinal direction of the plate 12, the rigidity of the bottom frame 2 (convex portion 28) can also be improved by this pair of protrusions 29. Therefore, it is possible to suppress the bottom frame 2 (convex portion 28) from being deflected by an impact due to a strike in the vicinity directly above the head sensor 10.

[0096] Further, among the pair of protrusions 29 arranged in the radial direction, the protrusion 29 located on the central side of the bottom frame 2 is formed at a position overlapping with the third plate 21d constituting the inner peripheral surface of the convex portion 28 in the vertical direction. Although not shown, the pair of protrusions 29 are formed at positions overlapping with the second plate 21c (see FIG. 4(b)) constituting the side surface of the convex portion 28 facing the circumferential direction in the vertical direction. By forming the protrusion 29 directly above the second plate 21c and the third plate 21d, it is possible to effectively suppress the bottom frame 2 (convex portion 28) from being deflected by an impact due to a strike in the vicinity directly above the head sensor 10.

[0097] In this way, by suppressing the deflection of the bottom frame 2 (convex portion 28) when the vicinity directly above the head sensor 10 is struck, the impact due to such a strike is more likely to be absorbed only by the deflection of the plate 12. Therefore, it is difficult for an error to occur in the sensitivity of the head sensor 10 (it is difficult to obtain the target output value), and thus the strike on the head 4 can be accurately detected.

[0098] In addition, since the plate 12 is fixed to a pair of protrusions 29 arranged along the longitudinal direction of the plate 12, the plate 12 can be firmly fixed to the bottom frame 2. Thereby, the strike on the head 4 can be accurately detected.

[0099] Here, in the present embodiment, a plurality (four in the present embodiment) of head sensors 10 are provided on the percussion instrument 100. For example, it is also possible to support these four head sensors 10 with a single plate 12. As an example of such a configuration, while fixing the center of the cross-shaped plate 12 to the protrusion 29, a configuration in which the head sensors 10 are attached to the four tip portions of the cross-shaped plate 12 is exemplified. Also in this configuration, since the head sensors 10 are supported at the tip portions of the plate 12 in a cantilever state, the impact near directly above each head sensor 10 can be absorbed by the deflection of the plate 12.

[0100] However, in a configuration where a plurality of head sensors 10 are attached to a single plate 12, when the vicinity directly above any one of the head sensors 10 is struck, the vibration caused by the strike is transmitted to the other head sensors 10 (sensor 10b) via the plate 12. When such vibration interference occurs, it becomes impossible to accurately detect the strike on the head 4.

[0101] In contrast, in the present embodiment, one head sensor 10 is attached to the tip side of a single plate 12. Thereby, when the vicinity directly above any one of the plurality of head sensors 10 is struck, it is possible to suppress the transmission of the vibration caused by the strike to the other head sensors 10 (sensor 10b). Therefore, the strike on the head 4 can be accurately detected.

[0102] Also, while the base end side in the longitudinal direction of the plate 12 is fixed to the bottom frame 2, the head sensor 10 is supported on the upper surface of the tip side of the plate 12. Therefore, when the head 4 is struck near directly above the cushion 10c, the plate 12 is likely to deflect. As a result, the impact at the time of striking the head 4 is easily absorbed, so that the transmission of the vibration caused by the strike to the other head sensors 10 via the plate 12 and the bottom frame 2 can be effectively suppressed.

[0103] In this way, vibrations during an impact on the head 4 are detected by the head sensors 10, but the intensity (velocity) and position of the impact are calculated based on the value obtained by summing the output values of the respective head sensors 10. As a method for calculating this sum value, for example, a configuration in which the peak values of the output waveforms of the respective head sensors 10 are added together (or the average value obtained by dividing that value by the number of sensors) is used as the sum value, or a configuration in which the output waveforms of the respective head sensors 10 are synthesized and the peak value of the synthesized waveform is used as the sum value is exemplified.

[0104] When calculating the intensity and impact value of the impact on the head 4 based on the magnitude of the sum value of the output values of the respective head sensors 10, it is preferable to arrange the respective head sensors 10 as close to each other as possible. This is because the closer the distance between the head sensors 10, the less likely a difference will occur in the output values (phase and peak value of the output waveform) of the respective head sensors 10 when the head 4 is impacted.

[0105] Therefore, in the present embodiment, the four head sensors 10 are arranged as close to each other as possible while being cantilever-supported by butting the tips of the four plates 12 against each other and facing them toward the center side of the bottom frame 2. And each head sensor 10 is connected in series on a substrate (not shown), the output waveforms of the respective head sensors 10 are synthesized, and the intensity and impact position of the impact on the head 4 are calculated based on the magnitude of the peak value of the synthesized waveform (the sum value of the output values of the respective head sensors 10).

[0106] By using the sum value of the output values of the respective head sensors 10, even if the output value of any one of the head sensors 10 becomes extremely large, the large output value is leveled by the output values of the other head sensors 10, so that the intensity and impact position of the impact on the head 4 can be calculated accurately.

[0107] Next, referring to FIG. 6, the percussion instrument 200 of the second embodiment will be described. The same parts as those of the first embodiment described above are denoted by the same reference numerals, and the description thereof will be omitted. FIG. 6 is a partially enlarged cross-sectional view of the percussion instrument 200 of the second embodiment. In FIG. 6, the end face of the cut portion of the percussion instrument 200 is shown, and one first connecting portion 31b located behind (the back side in the direction perpendicular to the paper surface) the cut surface is schematically shown.

[0108] As shown in FIG. 6, the housing 201 of the percussion instrument 200 of the second embodiment omits the reinforcing frame 9 of the first embodiment, and the top frame 3 is directly stacked on the bottom frame 202.

[0109] On the bottom frame 202, a female screw hole 220 is formed at a position corresponding to the through hole 32 of the top frame 3, and the top frame 3 is fixed to the bottom frame 202 by fastening the fixing bolt B4 inserted into the through hole 32 to the female screw hole 220.

[0110] On the lower surface of the bottom frame 202, a fastening portion 221 corresponding to the lug 7 (see FIG. 2) including the fastening portion 70, the lower surface portion 71, and the fixing portion 72, etc. of the first embodiment is integrally formed. Among the recesses 24a to 24c (see FIG. 2) described in the first embodiment, the recesses 24b and 24c are filled by the fastening portion 221, while a recess 24a is formed on the inner peripheral side (the right side in FIG. 6) of the fastening portion 221.

[0111] Although illustration is omitted, in the percussion instrument 200 of the present embodiment as well, a plurality of radially extending portions 21 (see FIG. 2) arranged in the circumferential direction are formed in the same manner as in the first embodiment, and a concave portion 24a is formed on the lower surface of the radially extending portion 21. As a result, it is possible to eliminate the need to form ribs on the radially extending portion 21 or reduce the number of ribs to be formed, while ensuring the rigidity of the bottom frame 202 (radially extending portion 21) by the concave portion 24a. Therefore, even when the bottom frame 202 is molded from resin, it is possible to suppress the occurrence of sink marks in the radially extending portion 21, so that the appearance of the percussion instrument 200 can be improved while reinforcing the bottom frame 202 with the concave portion 24a. Further, since the concave portion 24a is formed in a single groove shape continuous in the radial direction, it is possible to improve the appearance of the percussion instrument 100 while ensuring the rigidity of the bottom frame 202.

[0112] A female screw hole 222 for fastening the tension bolt B1 is formed in the fastening portion 221, and this female screw hole 222 is formed on the outer peripheral side of the concave portion 24a (a position aligned with the concave portion 24a in the radial direction). By providing the fastening portion 221 (female screw hole 222) to which the tension bolt B1 is fastened on the outer peripheral side of the radially extending portion 21 in which the concave portion 24a is formed, the load at the time of fastening the tension bolt B1 can be received in a region with high rigidity. Therefore, while ensuring the durability of the bottom frame 202 against the load at the time of fastening the tension bolt B1, the bottom frame 202 (housing 201) can be thinned.

[0113] Further, in FIG. 6, although one first connecting portion 31b is schematically illustrated, a plurality of the first connecting portions 31b are arranged in the circumferential direction in the same manner as in the first embodiment. As a result, no matter which position of the rim 5 is struck in the circumferential direction, the vibration caused by the strike is easily transmitted to the rim sensor 11 at the central portion 31a via the first connecting portion 31b. Further, the bottom frame 202 that supports the head sensor 10 and the top frame 3 that supports the rim sensor 11 are separate components. Therefore, it is possible to suppress the head sensor 10 from erroneously detecting a strike on the rim 5 and the rim sensor 11 from erroneously detecting a strike on the head 4, so that the detection accuracy of a strike on the rim 5 can be improved.

[0114] Also, in this embodiment as well, since the head sensor 10 (sensor 10b and cushion 10c) is attached to the tip side of the plate 12 supported in a cantilever state on the bottom frame 202, the impact at the time of hitting the head 4 can be absorbed by the bending of the plate 12. Thereby, it is possible to suppress the output value of the sensor 10b from becoming extremely large when the vicinity directly above the head sensor 10 (cushion 10c) is hit. Therefore, the sensitivity distribution of the head sensor 10 with respect to the impact on the head 4 can be made uniform.

[0115] Also, as described above, since the concave portion 24a is provided on the lower surface of the bottom frame 202 (radiating portion 21), a convex portion 28 corresponding to the concave portion 24a is formed on the upper surface side of the bottom frame 202 (radiating portion 21). Since the plate 12 is attached to the convex portion 28 with increased rigidity via the protruding portion 29, it is possible to suppress the bottom frame 202 (convex portion 28) from bending due to the impact by hitting in the vicinity directly above the head sensor 10. By suppressing the bending of the bottom frame 202 (convex portion 28), the impact by hitting in the vicinity directly above the head sensor 10 is easily absorbed only by the bending of the plate 12, so that the impact on the head 4 can be detected accurately.

[0116] Next, with reference to FIGS. 7 and 8, the percussion instrument 300 of the third embodiment will be described, and the same parts as those in the above-described embodiments are denoted by the same reference numerals and the description thereof is omitted. FIG. 7 is a perspective view of the percussion instrument 300 of the third embodiment, and FIG. 8 is a partially enlarged cross-sectional view of the percussion instrument 300 taken along line VIII-VIII in FIG. 7. In FIG. 7, the state where the head 4 (see FIG. 8) is removed is shown.

[0117] As shown in FIGS. 7 and 8, the percussion instrument 300 of the third embodiment includes a cylindrical shell 301 (body portion) that constitutes the housing portion, and the opening portion at the axial end of the shell 301 is covered by the head 4 (see FIG. 8).

[0118] The head 4 is attached to the shell 301 by an annular hoop 306. The hoop 306 has through holes 360 (see FIG. 8) formed at a plurality of locations in the circumferential direction thereof, and tension bolts B1 are inserted into the through holes 360. A plurality of lugs 307 are fixed to the outer peripheral surface of the shell 301 by fixing bolts B6. With the head frame 40 hooked on the hoop 306, tension is applied to the head 4 by fastening the tension bolts B1 to the tapped holes 370 of the lugs 307.

[0119] On the inner peripheral side of the shell 301, a first frame 302 that supports the head sensor 10 and a second frame 303 that supports the rim sensor 11 are fixed. The first frame 302 is composed of a mounting frame 320 to which the head sensor 10 is attached and a fixing fitting 321 for fixing the mounting frame 320 to the inner peripheral surface of the shell 301.

[0120] The fixing fitting 321 is an L-shaped fitting that is screwed to the inner peripheral surface of the shell 301, and the mounting frame 320 is a resin frame that extends in the radial direction of the shell 301. The mounting frame 320 is formed in a channel steel shape having a web and a flange, and both longitudinal ends of the mounting frame 320 are bent downward and fixed (screwed) to the fixing fitting 321.

[0121] A rib 320a is integrally formed at the center in the width direction of the mounting frame 320. Since the rib 320a is formed in a plate shape that extends in the longitudinal direction (radial direction) of the mounting frame 320, the rigidity of the mounting frame 320 can be improved by this rib 320a.

[0122] A pair of columnar protrusions 320b arranged in the longitudinal direction are integrally formed on the mounting frame 320, and a plate 312 is fixed to the pair of protrusions 320b. The plate 312 is formed in a substantially elliptical shape, and both longitudinal ends thereof are screwed to the pair of protrusions 320b. The head sensor 10 supported by this plate 312 includes a double-sided tape 10a, a sensor 10b, and a cushion 10c, similar to the first embodiment.

[0123] The second frame 303 includes a central portion 330 that supports the rim sensor 11, and a connecting portion 331 that extends radially from the central portion 330 and is connected to the inner peripheral surface of the shell 301. Each of these portions 330, 331 is integrally formed using a resin material. The outer edge portion of the connecting portion 331 is screwed to the inner peripheral surface of the shell 301 by a fixing bolt B6.

[0124] An annular rubber rim cover 305 is attached to the upper part of the hoop 306. The vibration generated when the rim cover 305 is struck is mainly transmitted to the connecting portion 331 of the second frame 303 via the head 4 (head frame 40) and the shell 301.

[0125] Since the second frame 303 that supports the rim sensor 11 is connected to the shell 301 at a plurality of locations in the circumferential direction (via a plurality of connecting portions 331), no matter which position of the rim cover 305 is struck in the circumferential direction, the vibration caused by the strike is easily transmitted to the rim sensor 11 of the central portion 330 via the connecting portion 331. Also, since the first frame 302 that supports the head sensor 10 and the second frame 303 that supports the rim sensor 11 are separate components, it is possible to prevent the vibration generated when the rim cover 305 (head 4) is struck from being erroneously detected by the head sensor 10 (rim sensor 11). Therefore, the detection accuracy of the strike on the rim cover 305 can be improved.

[0126] In addition, since a plurality (six in this embodiment) of connecting portions 331 that connect the central portion 330 of the second frame 303 and the shell 301 are arranged in the circumferential direction, through holes are formed between the connecting portions 331. By forming such through holes, the vibration generated when the head 4 is struck is easily released to the outside through the through holes. Therefore, the volume generated when the head 4 is struck can be reduced.

[0127] Here, in the present embodiment, the second frame 303 (connection portion 331) is connected to the shell 301 above the connection position between the shell 301 and the first frame 302 (the fixing position of the fixing bracket 321 with respect to the shell 301). Thereby, while shortening the vibration transmission path from the rim cover 305 to the rim sensor 11, the vibration transmission path from the rim cover 305 to the head sensor 10 can be lengthened.

[0128] And the first frame 302 extends from below the second frame 303 through between the connection portions 331 to above the second frame 303, and includes a mounting frame 320 to which the head sensor 10 is mounted. Thereby, while making it possible to position the connection position between the shell 301 and the second frame 303 above the connection position between the shell 301 and the first frame 302, the head sensor 10 can be brought into contact with the head 4.

[0129] Also, as described above, the vibration at the time of impact on the rim cover 305 is mainly transmitted to the second frame 303 via the head 4 (head frame 40) and the shell 301, but at the time of such impact, there is also vibration transmitted to the shell 301 via the tension bolt B1 and the lug 307. Therefore, in the present embodiment, the connection portion 331 of the second frame 303 and the shell 301 are clamped together with the lug 307 by the fixing bolt B6 (see FIG. 8). Thereby, at the time of impact on the rim cover 305, the vibration transmitted to the shell 301 via the tension bolt B1 and the lug 307 is easily transmitted to the rim sensor 11 via the connection portion 331, so that the detection accuracy of the impact on the rim cover 305 can be improved.

[0130] As described above, the description has been made based on the above embodiment, but it can be easily inferred that the present invention is not limited to the above embodiment at all, and various improvements and modifications are possible without departing from the spirit of the present invention.

[0131] In each of the above embodiments, the percussion instruments 100, 200, and 300 have been described as electronic percussion instruments, but this is not necessarily the case. For example, a configuration in which a fixing portion 72 extending to the inner peripheral side of the fastening portion 70 of the lug 7 is fixed to the lower surface of the bottom frame 2 (housing 1), or a configuration in which recesses 24a to 24c are formed on the lower surface of a radially extending portion 21 extending from the central portion 20 of the bottom frame 2 (bottom of the housing 1) is applicable to acoustic percussion instruments (drums) as well.

[0132] In each of the above embodiments, the case where the connection position between the body portion (body portion 30 or shell 301) and the frame (support portion 31 or first frame 302) that supports the rim sensor 11 is located above the connection position between the body portion and the frame (bottom frames 2, 202 or second frame 303) that supports the head sensor 10 has been described, but this is not necessarily the case. For example, a configuration in which the relationship of such connection positions is reversed may also be acceptable.

[0133] As an example of such a configuration, in the first and second embodiments, a configuration is exemplified in which the head sensor 10 attached to the support portion 31 (central portion 31a) is brought into contact with the head 4 while the rim sensor 11 is attached to the bottom frames 2 and 202. Further, as another example, in the third embodiment, a configuration is exemplified in which a fixing fitting 321 is fixed to the inner peripheral surface of the shell 301 above the connection position between the shell 301 and the connecting portion 331.

[0134] In the above first and second embodiments, the case where the recess 24a is formed in a groove shape that is continuous in the radial direction has been described, but this is not necessarily the case. For example, a configuration in which a rib (a plate-like wall extending in the circumferential direction) that divides the recess 24a is formed, that is, a configuration in which a plurality of intermittently arranged recesses in the radial direction are formed on the lower surface of the bottom frames 2 and 202 (radially extending portion 21) may also be acceptable.

[0135] In the above first and second embodiments, the case where the fastening portions 70 and 221 to which the tension bolt B1 is fastened are provided on the outer peripheral side of the recesses 24a to 24c (radially extending portion 21) has been described, but this is not necessarily the case. For example, the fastening portions 70 and 221 may be provided on the outer peripheral side of the sound emission hole 23 (a position aligned with the sound emission hole 23 in the radial direction).

[0136] In the above first and second embodiments, the case where the protrusion 29 is provided on the convex portion 28 formed on the upper surface side of the bottom frames 2 and 202, and the head sensor 10 is attached to the protrusion 29 has been described. However, it is not necessarily limited to this. For example, a protrusion 29 may be formed at a portion (e.g., the central portion 20) of the bottom frames 2 and 202 where the convex portion 28 is not formed.

[0137] In the above first and second embodiments, the case where a portion where the width dimension of the radial portion 21 gradually decreases or increases toward the outer peripheral side is formed, and the width dimensions of the recesses 24a and 24b are gradually formed to decrease or increase toward the outer peripheral side corresponding to the width dimension of the radial portion 21 has been described. However, it is not necessarily limited to this. For example, the width dimension of either one (or both) of the radial portion 21 and the recesses 24a and 24b may be constant from the inner peripheral side to the outer peripheral side. That is, the width dimensions (shapes) of the radial portion 21 and the recesses 24a and 24b can be set as appropriate.

[0138] In the above first and second embodiments, the case where the support portion 31 to which the rim sensor 11 is attached is connected to the body portion 30 over the entire circumference in the circumferential direction (via the annular portion 31c) has been described. However, it is not necessarily limited to this. For example, the annular portion 31c may be omitted, and the first connection portion 31b may be directly connected to the body portion 30. Even in such a configuration, no matter which position of the rim 5 is struck in the circumferential direction, the vibration caused by the strike is easily transmitted to the rim sensor 11 at the central portion 31a via the first connection portion 31b.

[0139] In the above-described first and second embodiments, the case where a plurality of through holes are formed between the connection portions 31b, 31d, and 31e has been described, but it is not necessarily limited to this. For example, the through holes between the connection portions 31b, 31d, and 31e may be omitted, and the support portion 31 may be a single plate-shaped frame. In this case, the head sensor 10 may be supported by the support portion 31 and brought into contact with the head 4, while the rim sensor 11 may be supported by the bottom frame 2. Also in this configuration, since the bottom frame 2 that supports the rim sensor 11 is connected to the body portion 30 (via the reinforcing frame 9) over the entire circumference in the circumferential direction, no matter which position of the rim 5 is struck in the circumferential direction, the vibration caused by the strike is easily transmitted to the rim sensor 11.

[0140] In the above-described first and second embodiments, the case where the support portion 31 that supports the rim sensor 11 is formed integrally with the body portion 30 has been described, but the body portion 30 and the support portion 31 may be separate components.

[0141] In the above-described first and second embodiments, the case where the body portion 30 (the annular portion 31c) and the first connection portion 31b are connected by the second connection portion 31d and the second connection portions 31d adjacent to each other in the circumferential direction are connected by the third connection portion 31e has been described, but it is not necessarily limited to this. For example, some or all of the plurality of second connection portions 31d and the third connection portions 31e may be omitted, or the annular portion 31c may be omitted and the first connection portion 31b may be directly connected to the body portion 30.

[0142] Also, when the second connection portion 31d is omitted, a connection portion (fourth connection portion) for connecting the first connection portions 31b adjacent to each other in the circumferential direction may be provided. With such a configuration, the points for restraining the deflection of the first connection portion 31b are reduced, and each first connection portion 31b arranged in the circumferential direction is more likely to deflect integrally, so that the vibration at the time of striking the rim 5 is easily transmitted to the rim sensor 11.

[0143] In addition, a part connecting the first connecting part 31b and the second connecting part 31d, or a part connecting the central part 31a and the second connecting part 31d may be provided. Also, a part connecting the central part 31a and the third connecting part 31e, or a part connecting the third connecting part 31e and the annular part 31c may be provided.

[0144] In addition, in the above first and second embodiments, the case where each part 31a - 31e of the support part 31 is integrally formed has been described. However, a part or all of these parts 31a - 31e may be formed separately from other parts.

[0145] In addition, in the above first and second embodiments, the case where each first connecting part 31b is located above the sound emission hole 23 and the second connecting part 31d is arranged along the edge of the sound emission hole 23 (radiating part 21) has been described. However, for example, the first connecting part 31b or the second connecting part 31d may be arranged above the radiating part 21. That is, the configuration of the support part 31 that supports the rim sensor 11 is not limited to the above form and can be changed as appropriate.

[0146] In the above first and second embodiments, the case where the plate 12 is fixed to the pair of protrusions 29 has been described. However, it is not necessarily limited to this. For example, the plate may be fixed to one or three or more protrusions 29.

[0147] In the above first and second embodiments, the case where a plurality of head sensors 10 are provided and one head sensor 10 is attached to the tip side of one plate 12 has been described. However, it is not necessarily limited to this. For example, the number of head sensors 10 may be one or more. Also, the plate 12 may be formed in a circular or polygonal shape according to the number of head sensors 10, and a plurality of head sensors 10 may be supported on one such plate 12.

[0148] As an example of such a configuration, while fixing the central portion of the plate 12 formed in a circular or polygonal shape (for example, a cross shape) to the protrusion 29, a configuration is exemplified in which the head sensor 10 is attached to a portion on the outer edge side of the plate 12 rather than the fixed portion (the tip portion that protrudes from the fixed portion and is in a cantilever state). With such a configuration, while reducing the number of parts, a plurality of head sensors 10 can be supported by the plate 12 in a cantilever state.

[0149] In the above-described first and second embodiments, the case where the tip of each of the plurality of plates 12 is directed toward the center side of the bottom frame 2 has been described, but it is not necessarily limited to this. For example, the tip of each plate 12 may be directed toward the outer peripheral side of the bottom frame 2.

[0150] In the above-described first embodiment, the case where the fixing bolt B2 inserted from the upper side into the bottom frame 2 (reinforcing frame 9) is fastened to the fixing portion 72 has been described, but it is not necessarily limited to this. For example, the fixing bolt B2 inserted from the lower side of the lug 7 may be fastened to the bottom frame 2 (reinforcing frame 9).

[0151] In the above-described first embodiment, the case where the annular reinforcing frame 9 made of a material harder than the bottom frame 2 is overlaid on the bottom frame 2, and each of these frames 2, 9 and the lug 7 (fixing portion 72) is fastened together by the fixing bolt B2 has been described, but it is not necessarily limited to this. For example, it is of course possible to fix the reinforcing frame 9 and the lug 7 to the bottom frame 2 with separate bolts. Also, it is possible to fasten the top frame 3, the reinforcing frame 9, and the bottom frame 2 together to the lug 7 with the fixing bolt B4.

[0152] Also, in the first embodiment, the case where the fixing bolts B2 to B4 are arranged along the radial direction has been described, but the fixing positions by these fixing bolts B2 to B4 may be shifted in the circumferential direction. Also, it is possible to omit one of the two fixing bolts B2 arranged in the radial direction, or to omit the fixing bolt B3.

[0153] In addition, when omitting one of the two fixing bolts B2 arranged in the radial direction, it is preferable to leave the fixing bolt B2 located on the inner peripheral side (the right side in Fig. 4(a)) (omit the fixing bolt B2 on the outer peripheral side). This is because the load acting when tightening the above-described tension bolt B1 is relatively small on the fixing bolt B2 on the inner peripheral side, which is relatively far from the contact point P.

[0154] Also, in the first embodiment, the case where the bottom frame 2 and the reinforcing frame 9 are screwed to the lower surface of the top frame 3 (annular portion 31c) on the outer peripheral side of the first connection portion 31b has been described. However, for example, the bottom frame 2 and the reinforcing frame 9 may be screwed to the first connection portion 31b or the second connection portion 31d. That is, the fixing structure between the frames 2, 3, 9 and the lug 7 is not limited to the above form and can be changed as appropriate.

[0155] In the above first embodiment, the case where the protruding portion 91 protrudes inward from the annular portion 90 of the reinforcing frame 9 has been described, but it is not necessarily limited to this. For example, the protruding portion 91 may be omitted and only the annular portion 90 may be screwed to the outer peripheral portion 22 of the bottom frame 2.

[0156] In the above third embodiment, the case where the second frame 303 that supports the rim sensor 11 is connected to the shell 301 at a plurality of locations in the circumferential direction (via a plurality of connection portions 331) has been described, but it is not necessarily limited to this. For example, the through holes between the connection portions 331 may be omitted and the second frame 303 may be a single plate-shaped frame. In this case, a configuration may be adopted in which the shell 301 and the first frame 301 are connected above the connection position between the shell 301 and the second frame 303. With such a configuration, the second frame 303 can be connected to the shell 301 over the entire circumference in the circumferential direction. Therefore, no matter which position of the rim cover 305 is struck in the circumferential direction, the vibration caused by the strike is easily transmitted to the rim sensor 11 via the second frame 303.

Explanation of Reference Numerals

[0157] 100, 200 Percussion instrument 1,201 Housing 2,202 Bottom Frame (part of the housing) 20 Central part 21 Radial part 22 Outer peripheral part 24a~24c Recessed parts 28 Protruding part 30 Barrel part 4 Head 70,221 Fastening part 9 Reinforcing frame 91 Protruding part B1 Tension bolt

Claims

1. A percussion instrument comprising a head for forming a striking surface, a housing having a cylindrical body portion with an upper end opening covered by the head, and a bottom frame constituting the bottom surface of the housing, wherein the bottom frame includes a central portion constituting the central part of the bottom frame, a plurality of radial portions radially extending from the central portion to the outer edge side of the housing, and an outer peripheral portion connecting the outer edges of the plurality of radial portions in the circumferential direction, and a concave portion extending from the central portion side to the outer peripheral portion side and a protrusion protruding downward from both circumferential sides of the concave portion and extending from the central portion side to the outer peripheral portion side are formed on the lower surface of the radial portion.

2. The percussion instrument according to claim 1, wherein the concave portion is formed in a groove shape continuous in the radial direction of the body portion.

3. An annular reinforcing frame formed of a material harder than the bottom frame and fixed to the outer peripheral portion, the percussion instrument according to claim 1, wherein the reinforcing frame includes a protruding portion protruding toward the inner peripheral side of the reinforcing frame and fixed to the radial portion.

4. A fastening portion provided on the outer peripheral side of the body portion and a tension bolt for applying tension to the head by being fastened to the fastening portion, the percussion instrument according to claim 1, wherein the fastening portion is provided on the outer peripheral side of the concave portion.

5. A head sensor for detecting vibration when striking the head in contact with the head, a convex portion having a shape corresponding to the concave portion is formed on the upper surface side of the radial portion, the percussion instrument according to claim 1, wherein the head sensor is supported by the convex portion.

6. A portion where the dimension in the circumferential direction gradually decreases or increases toward the outer peripheral side is formed in the radial portion, the percussion instrument according to claim 1, wherein the dimension in the circumferential direction of the concave portion is gradually formed to decrease or increase toward the outer peripheral side corresponding to the dimension in the circumferential direction of the radial portion.

7. A percussion instrument comprising a head for forming a striking surface, a housing having a cylindrical body portion with an upper end opening covered by the head, and a bottom frame constituting the bottom surface of the housing, wherein the method for reinforcing the bottom frame in the percussion instrument, the bottom frame including a central portion constituting the central part of the bottom frame, a plurality of radial portions radially extending from the central portion to the outer edge side of the housing, and an outer peripheral portion connecting the outer edges of the plurality of radial portions in the circumferential direction, A method for reinforcing a bottom frame, characterized in that a concave portion extending from the central portion side to the outer peripheral portion side and a protruding portion protruding downward from both circumferential sides of the concave portion and extending from the central portion side to the outer peripheral portion side are formed on the lower surface of the radial portion.

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