Electronic percussion instrument

Abstract

The present invention provides an electronic percussion instrument which makes it possible to prevent a piezoelectric element from freely vibrating over a long period as a result of being excited by vibration caused by hitting a hitting surface, and to avoid false detection of hitting.　Provided is an electronic cymbal comprising a main body part 1 having hitting surfaces F that can be hit by a performer, and piezoelectric elements 4 that are mounted on mounting surfaces Sa formed on the main body part 1 and convert vibration generated by hitting the hitting surfaces F into electric signals. The electronic cymbal can output the electric signals generated by the piezoelectric elements 4. A plurality of piezoelectric elements 4 is mounted on the same circumference with respect to the central axis C of the main body 1, and a circular buffer member D is mounted to position the vibration node of respective piezoelectric element 4 within an opening area of an inner diameter. The surface Da of the buffer member D is in contact with the mounting surface Sa, and the area including the vibration node of the piezoelectric element faces the mounting surface with the opening area therebetween.

Description

Electronic Percussion Instruments

[0001] The present invention relates to an electronic percussion instrument capable of outputting an electrical signal generated by a piezoelectric element.

[0002]

[0003] As disclosed in Patent Document 1, for example, a conventional electronic cymbal as an electronic percussion instrument includes an electronic cymbal body having a pad with a striking surface that can be struck by the player and a frame supporting the back side of the pad, a vibration sensor capable of detecting strikes on the striking surface of the pad, and an output cable for outputting the detection signal detected by the vibration sensor to an external device. When a player strikes the striking surface of the electronic cymbal body with a stick, the vibration sensor detects the strike and outputs the signal to an external device, allowing the electronic cymbal to be played in the same way as an acoustic cymbal. Patent Document 2 discloses an electronic drum equipped with a similar vibration sensor.

[0003] JP 2005-331972 JP 10-198375

[0004] However, the above-mentioned prior art technology, which uses a piezoelectric element as a vibration sensor, has the following drawbacks: The piezoelectric element is an element that converts vibrations generated by striking the striking surface into an electrical signal, and is attached to a mounting surface formed on the main body or a support member connected to the main body. However, if the entire piezoelectric element is attached so that it can vibrate freely, the piezoelectric element itself may continue to vibrate for a long period of time even when the striking surface is not being struck, which could result in false detection and repeated sound generation. This problem is not limited to electronic cymbals, but occurs in general electronic musical instruments that use a piezoelectric element to detect and output strikes on the striking surface. The applicant has therefore conducted extensive research to find a solution to this drawback.

[0005] The present invention has been made in consideration of the above circumstances, and its purpose is to provide an electronic percussion instrument that can suppress free vibration over a long period of time due to excitation of the piezoelectric element by vibrations caused by striking the striking surface, thereby avoiding erroneous detection of strikes.

[0006] The invention described in claim 1 is an electronic percussion instrument comprising a main body having a striking surface that can be struck by a player, and a piezoelectric element attached to a mounting surface formed on the main body and converting vibrations generated by striking the striking surface into an electrical signal, and capable of outputting the electrical signal generated by the piezoelectric element, wherein the piezoelectric elements are attached in multiple numbers on the same circumference around the central axis of the main body, and each piezoelectric element is attached with an annular buffer member that positions the vibration node of the piezoelectric element within an opening area of ​​the inner diameter, and the surface of the buffer member is attached in contact with the mounting surface while the area containing the vibration node of the piezoelectric element faces the mounting surface via the opening area.

[0007] According to a second aspect of the present invention, in the electronic percussion instrument of the first aspect, the piezoelectric elements are attached at positions symmetrical with respect to the central axis of the main body.

[0008] According to a third aspect of the present invention, in the electronic percussion instrument of the first aspect, the buffer member has an outer diameter that is substantially equal to the outer diameter of the piezoelectric element.

[0009] The invention described in claim 4 is characterized in that, in the electronic percussion instrument described in claim 1, the piezoelectric elements are attached in a position where the electrical signals generated by vibrations caused by striking the striking surface are in opposite phases to each other.

[0010] The invention of claim 5 is characterized in that, in the electronic percussion instrument of claim 2, the main body comprises an electronic cymbal having a pad portion on which the striking surface is formed and a frame portion that supports the back side of the pad portion, and the piezoelectric elements are attached to the back side of the frame portion at positions symmetrical with respect to the central axis of the main body.

[0011] The invention described in claim 6 is characterized in that, in the electronic percussion instrument described in claim 5, the frame portion has a cover member attached to the bottom surface that covers the piezoelectric element, and the edge of the cover member and the frame portion around its periphery are formed smoothly and continuously.

[0012] According to the invention of claim 1, a plurality of piezoelectric elements are mounted on the same circumference relative to the central axis of the main body, and an annular buffer member is attached so that the vibration nodes of each piezoelectric element are located within an opening in the inner diameter, and the surface of the buffer member is in contact with the mounting surface while the area including the vibration node of the piezoelectric element faces the mounting surface via the opening. This allows the plurality of piezoelectric elements mounted on the same circumference to smoothly follow the deflection of the main body while suppressing free vibration of the entire piezoelectric element due to tapping, thereby ensuring the voltage of the output electrical signal while accelerating attenuation and preventing false sounds. Furthermore, by having the buffer member be annular so that the vibration nodes of the piezoelectric elements are located within the opening in the inner diameter and the area including the vibration node of the piezoelectric element faces the mounting surface via the opening, free vibration of the piezoelectric element can be limited to high frequencies within the opening in the inner diameter of the buffer member, preventing a decrease in sensitivity when the striking surface is softly struck.

[0013] According to the invention of claim 2, the piezoelectric elements are attached at positions symmetrical with respect to the central axis of the main body, so that the waveforms with shifted periods cancel each other out, allowing the output waveform to attenuate quickly. In other words, when the striking surface is struck and the main body vibrates, the vibrations propagate with shifted waveform periods at positions symmetrical with respect to the central axis of the main body, gradually attenuating and stabilizing. On the other hand, the piezoelectric elements according to the present invention suppress free vibration of the entire piezoelectric element due to excitation when struck, and vibrate in accordance with the deflection of the main body. Furthermore, because the piezoelectric elements are attached at positions symmetrical with respect to the central axis of the main body, the output waveforms have shifted periods and cancel each other out, allowing the output waveform to attenuate quickly and suppress erroneous detection.

[0014] According to the invention of claim 3, the outer diameter of the buffer member is approximately equal to the outer diameter of the piezoelectric element, so that the free vibration of the entire piezoelectric element can be more reliably suppressed and the buffer member can more reliably follow the deflection of the main body due to tapping, thereby obtaining a sufficient electrical signal output.

[0015] According to the invention of claim 4, the piezoelectric element is mounted in a position where the electrical signals generated by the vibrations caused by striking the striking surface are in opposite phase to each other, so that the output waveforms can be efficiently canceled out, and the output waveforms can be attenuated early, thereby more reliably suppressing false detection.

[0016] According to the fifth aspect of the invention, the piezoelectric elements are attached to the rear side of the frame in symmetrical positions relative to the central axis of the main body, so that when applied to an electronic cymbal having a pad and a frame, the output waveforms are out of phase with each other and cancel each other out, allowing the output waveform to be attenuated early and preventing false detection even in large-diameter electronic cymbals.Furthermore, by using an annular cushioning member in the electronic cymbal, the free vibration of the piezoelectric element can be limited to high frequencies in the opening area of ​​the cushioning member's inner diameter, preventing a decrease in sensitivity when the striking surface is softly struck.

[0017] According to the invention of claim 6, the frame portion has a cover member attached to the bottom surface that covers the piezoelectric element, and the edge of the cover member and the frame portion around its periphery are formed smoothly and continuously, thereby improving the design of the bottom surface of the electronic cymbal.

[0018] 6 is a schematic diagram showing a piezoelectric element attached to the electronic cymbal; and FIG. 8 is a schematic diagram showing a pad portion of the electronic cymbal; a perspective view of the pad portion as seen from below; a perspective view of the frame portion of the electronic cymbal; a perspective view of the frame portion as seen from below; a perspective view of the cover member of the electronic cymbal; a three-sided view of a cushioning member attached to a piezoelectric element applied to the electronic cymbal; a graph showing output waveforms of two piezoelectric elements in the electronic cymbal of the present invention; a graph showing a state in which the output waveforms of two piezoelectric elements in the electronic cymbal of the present invention are combined; and a schematic diagram showing the shape of a piezoelectric element according to another embodiment of the present invention.

[0019] 1 to 6, the electronic cymbal according to this embodiment is configured with a main body 1 having a striking surface F that is composed of a pad 2 and a frame 3 and that can be struck by a player, a piezoelectric element 4 (vibration sensor) attached to the inner peripheral surface S of the frame 3 of the main body 1, and a cover member 8.

[0020] As shown in Fig. 1, the main body 1 is supported at a predetermined height by a support stand T that is extended vertically by stand legs Ta. The main body 1 is composed of a pad 2 having a striking surface F that can be struck by a player, and a frame 3 that supports the back side of the pad 2. The pad 2 has a plurality of openings Ha, and the frame 3 has a plurality of openings Hb, which communicate with each other to form openings H of the main body 1. Note that the reference symbol L in the figure denotes a tightening member that tightens and secures the main body 1 to the support stand T.

[0021] The pad 2 is made of a rubber material or soft resin (silicon rubber in this embodiment) that can be struck with a stick, and as shown in Figures 10 and 11, is a disk-shaped member with a through-hole 2a formed in the center through which a support stand T can be inserted. The striking surface F formed on the top surface of the pad 2 is composed of a cup portion Fb that bulges out from the center of the pad 2, an edge portion Fc that is formed on the periphery of the pad 2, and a bow portion Fa that is the area between the cup portion Fb and the edge portion Fc.

[0022] The frame 3 is made of hard resin or metal (ABS resin in this embodiment) and is a disk-shaped member having a through-hole 3a formed in the center, through which the support stand T can be inserted, as shown in Figures 12 and 13. The pad 2 is attached to the surface of the frame 3 to form the main body 1, and a bulge 3b is formed in the center of the main body 1, which bulges out to correspond to the cup Fb of the pad 2.

[0023] Furthermore, mounting surfaces Sa for mounting the piezoelectric element 4 are formed on the inner peripheral surface S of the bulging portion 3b of the frame portion 3. As shown in Figures 12 and 13, a plurality of such mounting surfaces Sa (four in this embodiment) are formed along the circumferential direction (circumferential direction) on the inner peripheral surface S of the frame portion 3 of the main body 1, and a piezoelectric element 4 is mounted on each mounting surface Sa.

[0024] As shown in Figures 14 and 15, the cover member 8 is made of an annular member with an opening 8a formed in the center through which a support stand T or the like can be inserted, and as shown in Figures 2 and 3, it is attached to the back side of the frame portion 3 so as to cover the inner surface S of the bulge portion 3b and to cover the substrate 5 (see Figures 3 to 6) on which a predetermined electric circuit is formed. This substrate 5 is electrically connected to each piezoelectric element 4, so that a detection signal from each piezoelectric element 4 is transmitted to the substrate 5. In the main body portion 1 according to this embodiment, the edge of the cover member 8 and the frame portion 3 around its periphery are smoothly connected.

[0025] The piezoelectric element 4 as a vibration sensor is attached to a mounting surface Sa formed on the main body 1 (frame 3) via a buffer member D, and is a sensor that can convert vibrations generated by striking the striking surface F into an electrical signal. As shown in Figures 8 and 9, it is configured with an upper electrode 4a made of, for example, a silver conductor, a lower electrode 4b made of, for example, a brass plate, and a piezoelectric ceramic 4c interposed between the upper electrode 4a and the lower electrode 4b.

[0026] Furthermore, the upper electrode 4a is connected to a wire h1, and the lower electrode 4b is connected to a wire h2, so that when a player strikes the striking surface F and vibrations are transmitted to the piezoelectric element 4, the entire element bends due to the vibration, and a voltage is generated according to the amount of bending. When a voltage is generated in this way, the upper electrode 4a acts as a positive electrode and the lower electrode 4b acts as a negative electrode, and a current flows through the wires h1 and h2, which is output as an electrical signal via the substrate 5 and the output cable 6.

[0027] However, although the piezoelectric element 4 generates a voltage and outputs an electrical signal when it bends in a direction b perpendicular to the mounting surface Sa, it is structured so that it is difficult to bend in a direction a parallel to the mounting surface Sa, and therefore vibrations in the direction b perpendicular to the mounting surface Sa have higher output characteristics (output characteristics resulting in a higher voltage or current) than vibrations in the direction a parallel to the mounting surface Sa.

[0028] Furthermore, the piezoelectric element 4 according to this embodiment has a cushioning buffer member D made of polyurethane foam or the like attached to its bottom surface, and as shown in Fig. 9, the surface Da of the buffer member D is in close contact with the mounting surface Sa and is attached with an adhesive or the like. In this way, the piezoelectric element 4 according to this embodiment has the buffer member D attached and is attached to the mounting surface Sa with the buffer member D in contact therewith, so that damage to the piezoelectric element 4 due to vibrations caused by tapping can be avoided. The material and shape of the buffer member D are not limited as long as it has cushioning properties and can be attached to the bottom surface of the piezoelectric element 4.

[0029] Incidentally, typical thin-plate piezoelectric elements have vibration nodes that do not displace when freely excited in the air. In a circular piezoelectric element like the piezoelectric element 4, a circular node occurs at a diameter that is 60% to 70% of the outer diameter, and the diameter of this nodal circle is called the node diameter. Since the state in which the piezoelectric element 4 vibrates with the node at the node diameter is the lowest-order fundamental vibration, it is known that the piezoelectric element 4 generates a large electrical signal most efficiently when vibrating with the node at the node diameter. For this reason, as described in paragraphs 0036 and 0038 of Patent Document 2, a technique has been known in the past in which a piezoelectric element is fixed by adhering it to a buffer member with an outer diameter equal to the node diameter of the piezoelectric element 4.

[0030] On the other hand, the buffer member D according to this embodiment is made of a member formed in a circular ring shape as shown in Fig. 16, and as shown in Figs. 9 and 10, the back surface Db is attached to the bottom surface (lower electrode 4b) of the piezoelectric element 4 with an adhesive or the like, and the front surface Da is attached to the mounting surface Sa with an adhesive or the like. Furthermore, the buffer member D has a ring shape that positions the vibration node of the piezoelectric element 4 within the opening area of ​​the inner diameter, and is configured so that the piezoelectric element 4 can vibrate freely in the opening area. Note that instead of being attached with an adhesive, other methods such as thermal welding may be used for attachment.

[0031] The buffer member D is attached with its surface Da in contact with the mounting surface Sa, and with the region including the vibration node of the piezoelectric element 4 facing the mounting surface Sa via the opening region of the buffer member D. This ensures free vibration of the piezoelectric element 4 within the opening region, and the buffer member D can narrow the region in which the piezoelectric element 4 can freely vibrate within the opening region, thereby shortening the wavelength of vibration of the piezoelectric element 4 compared to conventional technology in which the entire piezoelectric element 4 was allowed to vibrate freely. As a result, the frequency of the free vibration of the piezoelectric element 4 can be increased, and damping can be accelerated.

[0032] However, when the striking surface F is struck lightly, the vibration of the main body 1 is weak, and if the area allowing free vibration is small, the piezoelectric element 4 will not be excited and the strike will not be detected. Here, the buffer member D according to this embodiment is formed so that the inner diameter t2 of its opening area is larger than the diameter of the vibration node (node ​​diameter) of the piezoelectric element 4, thereby ensuring free vibration of the area including the vibration node of the piezoelectric element 4. In other words, by ensuring an opening area larger than the node diameter, sensitivity to light strikes is not impaired even when the outer end of the piezoelectric element 4 is attached with the buffer member D.

[0033] On the other hand, when the striking surface F is struck hard, the piezoelectric element 4 is excited violently, but in the prior art, the entire piezoelectric element 4 is allowed to vibrate freely, and the output waveform does not attenuate for a long period of time. Here, the buffer member D according to this embodiment is formed in an annular shape (circular in this embodiment), so the area in which the piezoelectric element 4 can freely vibrate can be narrowed to within the opening area, thereby shortening the wavelength of the vibration of the piezoelectric element compared to the prior art. As a result, the frequency of the free vibration can be increased, and attenuation can be accelerated. In other words, the buffer member D according to this embodiment is configured to "position the vibration node of the piezoelectric element within the opening area of ​​the inner diameter" in order to obtain sufficient sensitivity when struck softly, and is also "annular" in shape in order to accelerate attenuation when struck hard.

[0034] In this case, the inner diameter t2 of the hollow portion of the buffer member D is preferably 60 to 80% of the outer diameter t1, and most preferably 70% of the outer diameter t1. In the buffer member D according to this embodiment, the surface Da that comes into close contact with the mounting surface Sa is a flat surface, but the surface Da may have a slit formed in part or all around it, or the ratio between the inner diameter t2 and the outer diameter t1 may be another ratio, etc.

[0035] Furthermore, when a striking surface F located away from the piezoelectric element 4 is struck, the impact of the strike is attenuated by the deflection of the main body 1 before reaching the piezoelectric element 4, but this deflection becomes the main source of vibration and propagates to the piezoelectric element 4. Here, the buffer member D has a circular ring shape with an outer diameter t1 that is approximately equal to the outer diameter of the piezoelectric element 4. This allows the buffer member D to smoothly follow the vibration (deflection) of the main body 1 caused by the strike, and allows accurate detection of performance even when a striking surface F located away from the piezoelectric element 4 is struck. In other words, this embodiment is configured to detect not only the vibration of a portion of the main body 1 caused by the strike, but also the deflection of the entire main body 1.

[0036] Furthermore, an edge sensor E is attached to the periphery on the front surface side of the frame portion 3, and is capable of detecting a tap on the edge portion Fc of the pad portion 2. Like the piezoelectric element 4, the edge sensor E is electrically connected to the substrate 5 via wiring, and a detection signal is transmitted to the substrate 5. An output cable 6 is connected to the piezoelectric element 4 (vibration sensor) and the edge sensor E via the substrate 5, and is capable of outputting detection signals detected by the piezoelectric element 4 and the edge sensor E to the outside. An output jack J is formed at the tip of the output cable 6, and is capable of connection to an external signal processing device (not shown).

[0037] When the performer strikes the striking surface F of the pad section 2 with a stick to vibrate the main body section 1, the strength of the strike is detected by the piezoelectric element 4, and an electrical signal corresponding to that strength is output to an external signal processing device (not shown) via the output cable 6. A strike on the edge section Fc is identified according to the on / off state of the edge sensor E, and if a strike is detected when the edge sensor E is off, it is determined that the bow section Fa or the cup section Fb has been struck, and a predetermined musical tone is output.

[0038] 3 and 4, the shaft sleeve 7 is made of a cylindrical elastic member (rubber in this embodiment) with a through hole formed in the center. The shaft sleeve 7 is attached between the support stand T and the through hole 3a of the frame 3, and is designed to suppress transmission of vibrations generated by striking the main body 1 to the support stand T.

[0039] Here, the piezoelectric elements 4 according to this embodiment are mounted on the rear surface of the frame 3 in a number of equal intervals on the same circumference centered on the central axis C of the main body 1 (see FIGS. 3 to 5), and are mounted at symmetrical positions with respect to the central axis C of the main body 1, as shown in Fig. 5. That is, the piezoelectric elements 4 (two pairs of symmetrically arranged piezoelectric elements 4 in this embodiment) are mounted at symmetrical positions with respect to the central axis C of the main body 1, and when the striking surface F is struck, one pair of symmetrically arranged piezoelectric elements 4 and the other pair of symmetrically arranged piezoelectric elements 4 can convert the vibrations generated by the strike into electrical signals.

[0040] Incidentally, when the striking surface F of the pad section 2 of the main body 1 is struck during performance, the vibrations propagate with shifted waveform periods at positions symmetrical with respect to the central axis C of the main body 1, and gradually attenuate and stabilize. On the other hand, since a plurality of piezoelectric elements 4 according to this embodiment are attached on the same circumference with respect to the central axis C of the main body 1, and each has a buffer member D attached thereto, the free vibration of the entire piezoelectric element 4 is suppressed by striking, and the piezoelectric element 4 vibrates in accordance with the main body 1, and since the piezoelectric elements 4 are attached at positions symmetrical with respect to the central axis C of the main body 1, waveforms n1 and n2 with shifted periods are output as electrical signals, as shown in Fig. 17.

[0041] In this way, when multiple piezoelectric elements 4 are mounted on the same circumference with respect to the central axis C of the main body 1, and the waveforms n1 and n2 generated by symmetrically arranged piezoelectric elements 4 due to tapping are electrically or electronically combined, attenuation occurs relatively quickly, as shown in Figure 18. That is, immediately after a tap, the entire main body 1 is displaced integrally in the direction of the strike, causing the output waveforms of the piezoelectric elements 4 to overlap in period. Combining these overlapping waveforms ensures a sufficient output of the electrical signal required for tap detection. After a certain time has passed, vibration due to the flexure of the main body 1 becomes dominant, and the output waveforms of the symmetrically arranged piezoelectric elements 4 are offset in period. When combined, they cancel each other out, accelerating attenuation. Thus, by mounting the piezoelectric elements 4 on the same circumference and in symmetrical positions with respect to the central axis C of the main body 1, it is possible to prevent the waveforms from not attenuating for a long period of time after the strike, which could result in erroneous detection, and it is possible to accurately detect only the timing of the strike.

[0042] Furthermore, although the piezoelectric elements 4 according to this embodiment are mounted at symmetrical positions relative to the central axis C of the main body 1, it is preferable to mount them at positions where the electrical signals generated by vibrations caused by striking the striking surface F are in opposite phases. In other words, if the output waveforms of the piezoelectric elements 4 are in opposite phases, they will cancel each other out when combined, hastening the decay. This effectively prevents erroneous detection due to waveforms not decaying for a long period of time after striking, allowing for more accurate musical tone output.

[0043] However, since the electronic cymbal used in this embodiment is played by striking the entire surface over 360°, not just the area in front of the player, symmetry in sensitivity is required in the front, back, left and right directions. Therefore, it is more preferable to place the piezoelectric elements 4 not simply in positions where they are in opposite phase, but in positions symmetrical with respect to the central axis C.

[0044] 6 and 7, the mounting surface Sa in this embodiment is formed of a surface that is inclined in the vertical direction β from a horizontal plane (a plane including the horizontal direction α) toward the center of the main body 1, and the piezoelectric elements 4 are attached at equal intervals on the same circumference centered on the central axis C (see FIGS. 3 and 7) of the main body 1. That is, the inner peripheral surface S formed on the frame 3 of the main body 1 is formed in a truncated cone shape, and therefore a plurality of mounting surfaces Sa (four in this embodiment) are formed on the inner peripheral surface S at equal intervals along the circumferential direction (on the same circumference) centered on the central axis C, and the piezoelectric elements 4 are attached on each mounting surface Sa at the same circumference.

[0045] Furthermore, if the shape of the main body 1, including a predetermined region (a predetermined region on the inner or outer circumferential surface) and centered on the central axis C, is considered to be an imaginary cone shape, multiple mounting surfaces Sa (four in this embodiment) are formed on the same circumference around the central axis C on the side surface (a fan-shaped surface in the unfolded view, the same applies below) of the imaginary cone shape, and each mounting surface Sa is formed of a surface inclined at a predetermined angle from the horizontal plane to the vertical direction β toward the center of the frame 3 of the main body 1. This allows the piezoelectric element 4 to be arranged three-dimensionally (three-dimensionally formed by the horizontal direction α and the vertical direction β), and the piezoelectric element 4 can be sufficiently deflected by vibrations in either the horizontal direction α or the vertical direction β. This allows for good and uniform electrical signal output in response to vibrations in both the horizontal direction α and the vertical direction β associated with striking the striking surface F.

[0046] Furthermore, when the shape of the main body 1, which is centered on the central axis C and includes a predetermined region, is considered to be an imaginary cone shape, a plurality of mounting surfaces Sa (four in this embodiment) are formed on the side surface of the imaginary cone shape on the same circumference centered on the central axis C, and the mounting surfaces Sa in this embodiment are formed along the circumferential direction on the inner peripheral surface S of the frame 3 of the main body 1, and are made of flat surfaces (planar surfaces) corresponding to the mounting portion of the piezoelectric element 4 (the buffer member D in this embodiment) as shown in Figures 6 and 7, and have substantially the same shape (circular shape) and dimensions (diameter dimensions) as the outer shape of the piezoelectric element 4 as shown in Figures 5 and 6. Note that the outer shape of the piezoelectric element 4 is not limited to being circular, and may be elliptical or rectangular, and even in this case, the mounting surfaces Sa have substantially the same shape as the outer shape of the piezoelectric element 4.

[0047] According to this embodiment, a plurality of piezoelectric elements 4 are mounted on the same circumference relative to the central axis C of the main body 1, and an annular buffer member D is attached to position the vibration nodes of each piezoelectric element 4 within an opening in the inner diameter of the buffer member D. The surface Da of the buffer member D is in contact with the mounting surface Sa, while the region including the vibration node of each piezoelectric element 4 faces the mounting surface Sa via the opening. This suppresses free vibration of the entire piezoelectric element 4 due to striking, allowing the multiple piezoelectric elements 4 mounted on the same circumference to effectively follow the deflection of the main body 1. This ensures a sufficient voltage for the output electrical signal, accelerates attenuation, and prevents false sounds. Furthermore, by having the buffer member D be annular so that the vibration nodes of the piezoelectric elements 4 are positioned within the opening in the inner diameter of the buffer member D, and by having the region including the vibration node of each piezoelectric element 4 face the mounting surface Sa via the opening, free vibration of the piezoelectric element 4 is limited to high frequencies within the opening in the inner diameter of the buffer member D, preventing a decrease in sensitivity when the striking surface F is softly struck.

[0048] Furthermore, since the piezoelectric elements 4 according to this embodiment are attached at symmetrical positions with respect to the central axis C of the main body 1, waveforms with shifted periods cancel each other out, allowing the output waveform to attenuate quickly. That is, when the striking surface F is struck and the main body 1 vibrates, the vibrations propagate with shifted waveform periods at symmetrical positions with respect to the central axis C of the main body 1, and gradually attenuate and stabilize. On the other hand, the piezoelectric elements 4 according to this embodiment suppress free vibration of the entire piezoelectric element 4 due to excitation during striking, and vibrate in response to the deflection of the main body 1. Furthermore, since the piezoelectric elements 4 are attached at symmetrical positions with respect to the central axis C of the main body 1, the output waveforms with shifted periods cancel each other out, as shown in FIGS. 17 and 18 , allowing the output waveform to attenuate quickly and suppress erroneous detection.

[0049] In particular, the piezoelectric element 4 in this embodiment is mounted in a position where the electrical signals generated by the vibrations caused by striking the striking surface F are in opposite phases to each other, so that the output waveforms can be efficiently canceled out, and the output waveforms can be attenuated early, more reliably suppressing false detection.

[0050] Furthermore, because the outer diameter t1 of the buffer member D according to this embodiment is approximately equal to the outer diameter of the piezoelectric element 4, it can more reliably suppress free vibrations of the piezoelectric element 4 and can more reliably follow the deflection of the main body 1 due to tapping, so a sufficient electrical signal can be output even when striking a striking surface F that is distant from the piezoelectric element 4. In particular, the inner diameter t2 of the hollow portion of the buffer member D according to this embodiment is 60 to 80% of the outer diameter t1, and preferably the inner diameter t2 of the hollow portion of the interior is 70% of the outer diameter t1, so that it is possible to appropriately ensure the attachment strength to follow the free vibrations of the inner diameter region and the deflection of the main body 1, and it is possible to combine the functions of suppressing long-term vibrations when the striking surface F is hit hard and preventing a decrease in sensitivity when the striking surface F is hit softly.

[0051] Furthermore, since the piezoelectric elements 4 according to this embodiment are attached to the rear side of the frame 3 at symmetrical positions with respect to the central axis C of the main body 1, when applied to an electronic cymbal having a pad 2 and a frame 3, the output waveforms, which are out of phase with each other, cancel each other out, and the output waveform can be attenuated early to prevent false detection, even in a large-diameter electronic cymbal. Furthermore, since the buffer member D applied to the electronic cymbal is annular, free vibration can be ensured only at high frequencies within the inner diameter region of the buffer member D, preventing a decrease in sensitivity when the striking surface F is struck lightly.

[0052] In addition, the frame part 3 according to this embodiment has a cover member 8 attached to its bottom surface that covers the piezoelectric element 4, and the edge of the cover member 8 is smoothly connected to the frame part 3 around its periphery, thereby improving the design of the bottom part of the electronic cymbal. Also, the mounting surface Sa is formed from a surface that slopes from a horizontal plane (a plane that includes the horizontal direction α) to a vertical direction β toward the center of the main body part 1, and the piezoelectric elements 4 are attached at equal intervals on the same circumference around the central axis C of the main body part 1, so that even if the striking surface F is struck from any of a variety of directions, the piezoelectric elements 4 can stably and reliably convert the strike into an electrical signal and output it.

[0053] The mounting surface Sa according to this embodiment is formed along the circumferential direction on the outer or inner peripheral surface of the main body 1 and is made of a flat surface (a planar surface) corresponding to the mounting portion (buffer member D) of the piezoelectric element 4, so the piezoelectric element 4 can be more stably fixed to the mounting surface Sa than when fixed to a curved surface. The mounting surface Sa is not limited to a flat surface, and may be a curved surface forming the inner peripheral surface S (or outer peripheral surface).

[0054] In addition, the mounting surface Sa according to this embodiment has substantially the same shape and dimensions as the outer shape of the piezoelectric element 4, so that when mounting the piezoelectric element 4, the mounting position of the piezoelectric element 4 relative to the inner peripheral surface S of the main body 1 can be accurately determined, improving the positioning accuracy of the piezoelectric element 4. In other words, by mounting the piezoelectric element 4 in correspondence with the mounting surface Sa, the positioning of the piezoelectric element 4 is naturally performed, improving the positioning accuracy.

[0055] While the present embodiment has been described above, the present invention is not limited to this. For example, as shown in FIG. 19 , a cushioning member D having a surface Da made of an elliptical annular member (see FIG. 19( a)), a cushioning member D having a surface Da made of an oval annular member (see FIG. 19( b)), and a cushioning member D having a surface Da made of a rectangular annular member are also possible. In this embodiment, the main body 1 is composed of the pad 2 and the frame 3, and the mounting surface Sa is formed on the inner circumferential surface S of the frame 3. However, the mounting surface may be formed on the inner circumferential surface of a single main body 1. Furthermore, although this embodiment is applied to an electronic cymbal, it may also be applied to other electronic percussion instruments, such as an electronic drum having a piezoelectric element 4.

[0056] As long as the piezoelectric elements are attached in multiple numbers on the same circumference around the central axis of the main body, and a ring-shaped buffer member is attached to position the vibration node of each piezoelectric element within the opening area of ​​the inner diameter, and the surface of the buffer member is in contact with the mounting surface while the area containing the vibration node of the piezoelectric element faces the mounting surface via the opening area, the electronic percussion instrument can also be applied to instruments with different external shapes or with additional functions added.

[0057] REFERENCE SIGNS LIST 1 Main body 2 Pad 2a Insertion hole 3 Frame 3a Insertion hole 3b Bulging portion 4 Piezoelectric element (vibration sensor) 5 Board 6 Output cable 7 Shaft sleeve 7a Insertion hole 8 Cover member 8a Opening S Inner surface Sa Mounting surface T Support stand Ta Stand leg J ​​Output jack F Striking surface Fa Bow Fb Cup Fc Edge L Tightening member H, Ha, Hb Opening D Cushioning member Da Front surface Db Back surface E Edge sensor

Claims

1. An electronic percussion instrument comprising: a main body having a striking surface that can be struck by a player; and a piezoelectric element that is attached to a mounting surface formed on the main body and converts vibrations generated by striking the striking surface into an electrical signal, the electronic percussion instrument being capable of outputting an electrical signal generated by the piezoelectric element, wherein the piezoelectric elements are attached in multiple numbers on the same circumference about the central axis of the main body, and annular buffer members are attached to position the vibration nodes of each of the piezoelectric elements within an opening area on the inner diameter, and the surface of the buffer member is in contact with the mounting surface, while the area including the vibration node of the piezoelectric element faces the mounting surface via the opening area.

2. The electronic percussion instrument according to claim 1, wherein said piezoelectric elements are attached at symmetrical positions with respect to the central axis of said main body.

3. The electronic percussion instrument according to claim 1, wherein the outer diameter of said buffer member is approximately equal to the outer diameter of said piezoelectric element.

4. The electronic percussion instrument according to claim 1, wherein said piezoelectric elements are attached in positions such that electrical signals generated by vibrations caused by striking said striking surface are in opposite phases to each other.

5. The electronic percussion instrument according to claim 2, characterized in that the main body comprises an electronic cymbal having a pad portion on which the striking surface is formed and a frame portion supporting the rear side of the pad portion, and the piezoelectric elements are attached to the rear side of the frame portion at symmetrical positions with respect to the central axis of the main body.

6. An electronic percussion instrument as described in claim 5, characterized in that a cover member that covers the piezoelectric element is attached to the bottom surface of the frame portion, and the edge of the cover member and the frame portion around its periphery are formed smoothly and continuously.

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