JP2007156048A - Sound attenuating drumhead and sound attenuating drum - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a sound attenuating drum and a snare drum with which the same feeling of hitting with acoustic drums can be obtained. <P>SOLUTION: The sound attenuating drumhead is constituted by forming pores in a polymer film in 60° zigzag pattern and fitting a ring which has a larger diameter than the body of a drum to the holed polymer resin film having the pores formed. The sound attenuating drum is constituted by mounting the sound attenuating drumhead on one opening end surface of a body. A snappy sound attenuating drum is constituted by closely arranging a plurality of polymer resin films with bored strip holes formed of holed polymer resin films on the back of the drumhead of the sound attenuating drum. Further, an electric drum is constituted by arranging a resonance member constituted by mounting a vibration pickup on a metal plate containing copper in the body in contact with the holed polymer resin films constituting the drumhead. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention is configured using a sound reduction drum head and a sound reduction drum head that are suitable for application to a sound reduction drum used as a practice drum or a sound reduction drum that can be used as an electric drum in combination with a loudspeaker. Related to the sound reduction drum.

As disclosed in Patent Document 1, the present applicant has proposed an electric snare drum using a wire mesh as a drum head member and a loudspeaker for the electric snare drum.
Since the electric snare drum proposed previously uses a wire mesh as a drum head, no sound is produced even when the drum head is actually hit, so that it is suitable for practice. That is, instead of producing sound, a vibration pickup is provided, and the drum sound can be heard without disturbing the surroundings by listening to an electric signal picked up by the vibration pickup with headphones, which is suitable for practice. Moreover, if it emits as a sound with a loudspeaker, it can be used as a drum for a stage.

Two methods are currently considered for generating electrical drum sound signals. One of them is that when the hitting surface is hit with a stick, the vibration that is hit is detected with an electric pickup, and the drum sound signal is generated from a sound source device provided separately as a trigger of the detection signal,
There is a type in which a vibration pickup is attached to the drum itself, the vibration of the drum itself is converted into an electric signal, and this electric signal is output as a drum sound signal.
Regardless of the method used for the former method, the sound to be emitted is determined by the drum sound signal prepared in the sound source device.

On the other hand, since the latter uses the struck vibration itself as a drum sound signal, a natural drum sound signal can be obtained. That is, by changing the way of striking, the difference can be expressed as a change in sound. In this respect, the latter form is superior. The electric snare drum proposed in Patent Document 1 is an electric drum of the latter type.
Japanese Patent Laid-Open No. 11-237877

Since the electric drum proposed in Patent Document 1 uses a wire mesh for the drum head, there is a drawback that the wire mesh is deformed into a depressed state when the hitting surface is strongly hit. In addition, since the wire mesh is woven in the direction in which the wires are orthogonal, the wire mesh has a strong strength against the tension in the axial direction of the wire, but has a low tensile strength in the oblique direction. For this reason, there is a drawback that the strength or tone color of the generated drum sound signal changes due to the relationship between the hit point and the mounting position of the vibration pickup.
SUMMARY OF THE INVENTION An object of the present invention is to provide a sound-reducing drum head in which the drum head is not deformed even when strongly struck, and the drum sound signal does not change in strength or tone depending on the striking point position. Sound reduction drums using drum heads and snare drum sounds with a simple structure that generate sounds as close as possible to snappy sounds, and sounds that are as close as possible to the sounds of various drums such as bass drums, tom toms, and bass toms. It is an object of the present invention to provide a sound reduction drum capable of generating an electrical signal that can be generated.

In the present invention, a perforated polymer resin film having pores with a density of about 20 to 45% is used as a drum head member.
The present invention is further characterized in that the arrangement of the pores formed in the perforated polymer resin film is a 60 ° staggered pattern.
Furthermore, the present invention proposes a sound-reducing drum in which the drum head member is stretched on one opening end of the drum.
Further, according to the present invention, in the above-mentioned sound reduction drum, a plurality of strip heights supported in a posture parallel to each other by being given a predetermined tension in the vicinity of the back surface of the perforated polymer resin film stretched on the drum. We propose a sound reduction drum equipped with a molecular resin film.

Further, according to the present invention, in the above-mentioned sound reduction drum, the strip polymer resin film is characterized in that pores are formed at a density of about 20 to 45% as in the case of the perforated polymer resin film. To do.
Further, according to the present invention, in the above-described sound-reducing drum, a resonance member that is mounted on the inner side of the drum and is disposed in contact with a part of the perforated polymer resin film, and a vibration that converts the vibration of the resonance member into an electric signal. A sound reduction drum is proposed as a structure with a pickup.
According to the present invention, in the sound reduction drum, the resonance member is constituted by a substantially rectangular metal plate and a weight attached to one end of the metal plate, and the metal plate is on an end side where the weight is not attached. And a free end of the bent portion is attached to the drum body, the bent portion is brought into contact with the back surface of the perforated polymer resin film, and the perforated polymer resin film is We propose a sound-reducing drum with a structure that extends from the contact point to the weight mounting position in a direction that gradually moves away from the back surface of the perforated polymer resin film.

According to the present invention, in the above-described sound reduction drum, the metal plate constituting the resonance member has a cut in the longitudinal direction and the short side direction, and a plurality of resonance portions having different resonance frequencies are provided by the cut, and each resonance We propose a sound-reducing drum with a structure that converts the resonance of the part into an electrical signal using a vibration pickup.
According to the present invention, in the above-described sound reduction drum, the resonance member is constituted by a substantially rectangular metal plate, and one short side of the metal plate is press-contacted to a joint portion between the perforated polymer resin film and the drum. A first bent portion that is a contact portion with the perforated polymer resin film, is formed at a predetermined distance from the contact portion, and is configured to bring the other end of the metal plate closer to the inner wall of the body; A second bent portion that is formed at a predetermined distance from the bent portion and that has the other end of the metal plate as a mounting surface parallel to the inner wall surface of the body, and the contact portion and the first bent portion A structure in which a vibration pickup is mounted between the two is used.
According to the present invention, in the above-described sound reduction drum, the metal plate constituting the resonance member is made of copper or a metal plate containing copper.

According to the sound-reducing drum head of the present invention, since the polymer resin film is used as the drum head member, deformation such as a dent is not caused even if it is strongly hit. However, the hit feeling is close to that of an acoustic drum, so it is suitable for practice. Furthermore, since the pores were formed in the polymer resin film with a density of about 20 to 45%, even if it was struck while being stretched on the opening end of the trunk, the sound generation was slight and the surrounding area was affected. There is nothing.
However, since the pores are arranged in a 60 ° staggered structure, a uniform tensile strength can be given in any direction of 360 °. As a result, there is no difference in the detection sensitivity of the drum sound signal due to the relationship between the hit point and the mounting position of the vibration pickup, and there is no phenomenon that the timbre changes.

By the way, in order to give a uniform tensile strength in any direction of 360 ° in the perforated drum head, a structure in which pores are formed concentrically from the center of the drum head is conceivable in addition to the 60 ° staggered structure. However, with this structure, there is a drawback in that the process of forming concentric pores in the drum head member is costly. That is, since a jig in which the blades for punching out the pores are arranged concentrically must be prepared, the cost required for this jig is expensive.
In contrast, in the case of a 60 ° staggered structure, pores are formed with a jig in which blades are arranged to form pores in a direction perpendicular to the moving direction while feeding out a resin sheet wound around a winding shaft. In addition, since the formation position of the pores only needs to be punched while being alternately shifted at intervals of 1/2 of the arrangement pitch of the blades in a direction orthogonal to the feeding direction of the resin sheet at every predetermined feeding interval, the manufacturing cost is Inexpensive.

  Further, the sound reduction drum according to the present invention has a plurality of strips formed of a polymer resin film disposed close to the back surface of the perforated polymer resin film stretched on the trunk, so that the drum head is hit. In this case, this strip contacts the surface of the perforated polymer resin film constituting the drum head, and a snappy sound can be obtained by this contact. That is, a snare drum can be obtained. The strip is formed by cutting a polymer resin film into strips, or by forming a rectangular strip having a predetermined width, and forming a cut in the longitudinal direction of the strip. Even if manufactured by any method, the structure is simple, so that it can be manufactured at low cost. In addition, the polymer resin film constituting the strip is infinitely acoustic when the finely perforated polymer resin film in which pores are formed with an aperture ratio of about 20 to 45% as in the drum head member is used. A raw sound close to the snare drum sound and a sound close to the snare drum sound can be reproduced from the loudspeaker.

Further, the sound reduction drum according to the present invention has a structure in which a resonance member partially in contact with the drum head member inside the drum and a vibration pickup that converts vibration of the resonance member into an electric signal are provided on the resonance member. Thus, a signal obtained by faithfully converting the vibration of the drum head member into an electric signal can be obtained from the vibration pickup. That is, it is possible to obtain a drum sound signal that can reproduce a sound as close as possible to the drum sound.
Further, according to the present invention, since the resonance member is made of a metal plate and a weight is attached to the free end of the metal plate, the resonance frequency of the metal plate can be freely selected according to the weight of the weight. As a result, even if the shape of the metal plate constituting the resonance member is constant, the resonance sound of the trunk can be generated according to the weight of the weight. In other words, in the acoustic drum, the resonance frequency of the drumming is changed due to the deepness and shallowness of the drum. Electric drums that generate the frequency of Therefore, it is possible to obtain an excellent effect that can make various drums at low cost.

Further, according to the present invention, a notch is formed in the metal plate constituting the resonance member, and a plurality of resonance parts having different resonance frequencies are provided by the notch, and the resonance of the plurality of resonance parts is separately provided by the vibration pickup. Since each of them is structured to take out as an electric signal, it is possible to obtain a drum sound signal having a wide frequency band of contained frequency components. That is, a drum sound signal having a thick tone, for example, various drum sounds such as bass drum, tom tom, or bass tom tom can be obtained.
Further, according to the present invention, since the resonance member is made of copper or a metal plate containing copper, a resonance waveform peculiar to copper can be obtained, and a drum sound signal having a good tone can be obtained.

Pores are formed in a polymer resin film such as polyethylene terephthalate in a 60 ° zigzag pattern with a density of about 20 to 45% of the aperture ratio to obtain a perforated polymer resin film. At the same time, this perforated polymer resin film is cut into a circle having a diameter larger than the diameter of the drum body, and a ring is attached to the periphery thereof to constitute a sound-reducing drum head.
A sound-reducing drum head is constructed by stretching a sound-reducing drum head supported by a ring on one open end face of a cylindrical body.
A plurality of strip polymer resin films formed into strips as necessary on the back surface of the sound reduction drum head constituting the sound reduction drum are arranged in parallel with each other and given a predetermined tension. As the plurality of strip polymer resin films, it is desirable to use a perforated polymer resin film in which pores are formed in a 60 ° staggered pattern as in the sound-reducing drum head proposed in the present invention. The plurality of strip polymer resin films arranged on the back surface of the sound reduction drum head can act as so-called snappy, generate a snappy sound, and make the sound reduction drum act as a snare drum.

A resonance member that is at least partially perforated and is in contact with the polymer resin film is provided inside the drum of the sound reduction drum. The resonance member is made of copper or a metal plate containing copper, and a vibration pickup is attached to the resonance member, and the resonance vibration of the resonance member is converted into an electric signal and output as a drum sound signal.
Therefore, according to the sound reduction drum provided with the vibration pickup, in addition to being able to listen to the sound through the headphones, if the drum sound signal output from the vibration pickup is input to the loudspeaker, the drum sound is emitted from the loudspeaker. Can do. The drum sound can be freely changed in timbre, decay time, etc. by changing the position where the drum head is struck, the strength of the struck, and the like, and a performance expression equivalent to that of an acoustic drum can be realized.

1 and 2 show an embodiment of a sound-reducing drum head proposed in the present invention. The sound reduction drum head 10 according to the present invention includes a perforated polymer resin film 11 and a ring 13 that supports the periphery of the perforated polymer resin film 11.
As the polymer resin film, for example, a polymer resin film such as PET (polyethylene terephthalate) or polypropylene having a thickness of about 200 μm to 500 μm can be used. The pores 12 formed in the polymer resin film have a diameter of about 0.5 to 2 mm, for example, and an aperture ratio of about 20 to 45%.
In the present invention, a 60 ° zigzag pattern is adopted as the arrangement pattern of the pores 12. The 60 ° staggered pattern means an arrangement pattern in which pores exist at intervals of 60 ° around each hole, as shown in FIG. 3, for example. As a method for forming the pores 12, for example, a blade for forming the pores 12 in an arrangement corresponding to two rows on the X1 line and the X2 line shown in FIG. 3 is prepared. The blades can be lowered while being sequentially shifted in the longitudinal direction to form the pores 12 or can be formed continuously by lowering the blade every time the belt-like polymer resin sheet is sequentially moved at a constant interval.

  According to this 60 ° staggered pattern, a uniform tensile strength can be obtained in any direction of 360 °. Therefore, in a state where the perforated polymer resin film 11 is stuck to one opening surface of the drum constituting the drum, it can be stretched with a uniform tension in any direction of 360 °. As a result, the tapping feeling is as close as possible to that of an acoustic drum. Furthermore, by setting the diameter of the pore 12 to about 0.5 to 2.0 mmφ, an accident in which the tip of the stick enters the pore 12 does not occur. Further, a sufficient sound reduction effect can be obtained by setting the aperture ratio of the pores 12 to about 20 to 45%.

FIG. 4 shows an example of a sound reduction drum in which a perforated polymer resin film 11 is attached to a drum as a drum head member. 4, 20 is a cylindrical barrel, 21 is a lug attached to the outer peripheral surface of the barrel 20, and 30 is press-contacted to one opening surface of the barrel 20 with tension applied to the perforated polymer resin film 11. A rim 31 and a tension bolt 31 for applying a pressure contact force to the rim 30 are shown.
By screwing the tension bolt 31 into the lug 21, the rim 30 is pressed downward, and the ring 13 moves downward as the rim 30 moves, so the perforated polymer resin film moves as the ring 13 moves. 11 is pressed against one opening end face of the barrel 20, and the perforated polymer resin film 11 is in a state where tension is applied in all directions of 360 ° inside the opening end face. The perforated polymer resin film 11 is uniformly tensioned toward the outer periphery. In this state, the perforated polymer resin film 11 is stretched with uniform tension in all directions by setting the arrangement pattern of the pores 12 to a 60 ° staggered pattern.

In addition to the 60 ° staggered pattern, the arrangement pattern of the pores 12 that can obtain a uniform tension in all directions, and a method of forming the pores 12 concentrically from the center position around the axial center position of the trunk 20 are also conceivable. . However, in order to form the concentric pores in a concentric manner, as described above, prepare a jig formed by arranging blades for forming the pores 12 on the end faces of the cylinders in different diameters, Since this jig must form the concentric pores 12, there is a drawback in that the manufacturing cost of the jig is high. For this reason, the present invention employs a 60 ° staggered pattern.
4, the other opening end face of the drum 20 is open, and hitting the striking surface of the sound reduction drum head 10 makes it as close as possible to the acoustic drum. Since the drum sound reduced by about 30 dB is generated, it is possible to practice the drum without disturbing the surroundings. However, the feel is almost as close as that of an acoustic drum, so it is ideal for practicing drums.

5 and 6 show a third embodiment of the present invention. In the third embodiment, a snappy is attached to the sound reduction drum shown in FIG. 4, and the sound reduction drum acts as a snare drum with a snappy. In FIG. 5, the structure of a portion such as a rim which is not necessary for the description of this embodiment and the structure for removing the snappy from the drum head and switching to a non-contact state are omitted.
Reference numeral 40 shown in FIGS. 5 and 6 denotes a snappy. As shown in FIG. 6A, the snappy 40 is a fine polymer film in which a perforated polymer resin film 11 having a structure equivalent to that of the perforated polymer resin film 11 constituting the sound reduction drum head 10 is cut into strips. The resin film 11 ′ and a support member 41 that supports the plurality of strip-perforated polymer resin films 11 ′ in parallel postures can be formed.

  The strip-shaped perforated polymer resin film 11 ′ is not necessarily separated into strips, and a support member 41 is attached to both ends of the strip-shaped perforated polymer film 11 as shown in FIG. In this case, the cuts S may be formed in parallel with each other, and the slit-perforated polymer resin film 11 ′ in a posture parallel to each other may be formed by the cuts S. The width W1 of the snappy 40 is determined in accordance with the diameter of the sound reduction drum to be mounted, but is approximately 50 to 100 mm. The width W2 of the fine-hole-perforated polymer resin film 11 'is about 2 to 4 mm.

The snappy 40 is attached to the tension adjusting means 50 via the support member 41. By this tension adjusting means 50, the striped perforated polymer resin film 11 ′ constituting the snappy 40 is disposed close to the back surface of the perforated polymer resin film 11 constituting the sound reduction drum head 10.
FIG. 7 shows an example of the tension adjusting means 50. The tension adjusting means 50 shown here includes a frame-shaped movable base 51, a support member 52 that supports the snappy mounting portion 51 </ b> A of the movable base 51 in a direction parallel to the back surface of the drum head 10, and a barrel 20. The case where it comprises with the tension | tensile_strength adjusting screw 53 which adjusts the amount of protrusion from the inner wall of the trunk | drum 20, and adjusts the rotation position of the movable stand 51 with this amount of protrusion is shown. If the tension adjusting screw 53 is rotated by this configuration, the tension applied to each of the fine-hole-perforated polymer resin resin film 11 ′ constituting the snappy 40 can be adjusted. By adjusting the tension applied to the fine-line-perforated polymer resin film 11 ′, the resonance frequency of the fine-line-perforated polymer resin film 11 ′ can be changed, and the sound quality of the snappy sound can be adjusted.

  According to the snappy 40 shown in FIG. 5 and FIG. 6, a striped perforated resin film 11 ′ in which a polymer resin film having the same structure as the perforated polymer resin film 11 constituting the sound reduction drum head 10 is formed into a strip. As a result, it was possible to obtain a sufficiently reduced snappy sound. Further, according to the snappy composed of the polymer resin film 11 ′ having a fine hole perforated sound, a snappy sound similar to the snappy sound in the acoustic drum could be obtained.

8 and 9 show a fourth embodiment of the present invention. In this embodiment, an embodiment of a sound reduction drum is provided in which vibration detecting means is provided inside the body 20 and a function of allowing the sound of the sound reduction drum to be heard as a sound by a headphone or a loudspeaker is added.
In the embodiment shown in FIGS. 8 and 9, the resonance member 60 is constituted by a metal plate bent at an acute angle, one bent piece is mounted on the inner wall of the barrel 20, and the other bent piece is placed in the inner space of the barrel 20. Support in a protruding position. In this case, the curved portion formed at the boundary of the bent piece is brought into contact with the back surface of the perforated polymer resin film 11 constituting the sound reduction drum head 10, and the vibration of the perforated polymer resin film 11 is applied to the resonance member 60. Communicate.

  The resonance member 60 is formed of a metal plate having a thickness of at least about 1.0 to 2.0 mm including copper, such as a copper plate or brass. A rectangular metal plate is bent at an acute angle in the middle of the longitudinal direction, one bent piece is used as an attachment member to the body 20, and the other bent piece is used as a resonance member 60. For example, as shown in FIG. 9, a longitudinal groove 61 and a lateral groove 62 formed in the short side direction are formed in a portion that acts as the resonance member 60, and the resonance member 60 is partitioned into a plurality of resonance portions 63A, 63B, 63C, and 63D. . Furthermore, a case is shown in which a weight 64 is attached to the ends of two resonance members divided by the longitudinal groove 61 and the resonance frequency of the two resonance members is adjusted by the weight of the weight 64.

A vibration pickup 66 is attached to each resonance portion 63A, 63B, 63C, 63D, and the resonance vibration of each resonance portion 63A to 63D is converted into an electric signal by these vibration pickups 66. As the vibration pickup 66, for example, a piezoelectric vibration pickup can be used. The detection signals of the plurality of vibration pickups are mixed by a mixing circuit (not shown), and the mixed sound signal is output to the outside of the barrel 20 as an electrical signal.
According to the embodiment shown in FIGS. 8 and 9, the resonance frequencies of the two resonance plates can be greatly different depending on the weight of the weight 64. Furthermore, the resonance frequency of each resonance part 63A-63D can be varied depending on the formation position of the lateral groove 62 for constituting each resonance part 63A, 63B, 63C, 63D. As a result, a drum sound signal in which frequency components are distributed over a wide band as a whole can be obtained, and a drum sound signal having a good timbre can be obtained. Further, by using copper or a metal plate containing copper as the resonance member 60, a tone similar to an acoustic drum could be obtained.

10 and 11 show examples of other vibration pickups. In this embodiment, one end of a rectangular resonance member 60 is abutted against the joint portion between the perforated polymer resin film 11 constituting the sound-reducing drum head 10 and the body 20, and the perforated polymer constituting the sound-reducing drum head 10. The case where the resonance member 60 is brought into contact with the portion closest to the vibration node of the resin film 11 and a high energy vibration is applied to the resonance member 60 from the portion closest to the vibration node is shown.
For this purpose, one end of a rectangular metal plate is tapered, and this tapered portion is inserted into a joint portion between the sound-reducing drum head 10 and the barrel 20, and a first bent portion 67A is formed, and this first bent portion is formed. The second bent portion 67B is formed at a position where the other end side of the metal plate is brought close to the inner wall surface of the barrel 20 by the portion 67A and joined to the inner wall surface of the barrel 20, and is bent at the second bent portion 67B. The part is set in a posture parallel to the inner wall surface of the barrel 20, and the parallel surface is caused to act as a mounting surface to the inner wall surface of the barrel 20.

As shown in FIG. 11, a plurality of vibration pickups 66 are mounted between the tapered tip and the first bent portion 67 </ b> A, and the vibrations of the respective parts are converted into electric signals by the plurality of vibration pickups 66.
According to the configuration of the fourth embodiment, a crisp drum sound including many high sound components was obtained.

  In FIG. 12, a folded portion 67 is formed in the resonance member 60 shown in FIG. 9, and the folded portion 67 is inserted into a groove formed on the upper edge of the drum 20, and the sound-reducing drum head 10, the drum 20, The case where it is set as the structure pinched | interposed between and supported is shown. The resonance member 60 may be fixed to the cylinder 20 with a main screw or the like in a groove formed on the upper edge of the cylinder 20. In any case, the resonance member 60 comes into contact with the perforated polymer resin film 11 constituting the sound reduction drum head 10, and the vibration of the perforated polymer resin film 11 is transmitted to the resonance member 60.

13 and 14 show a seventh embodiment of the present invention. In this embodiment, a case where the resonance member 60 is supported by a one-contact beam structure inside the trunk 20 is shown. That is, a notch is formed in the upper edge of the trunk 20, and the resonance member 60 is pressed against the upper edge of the trunk 20 by a wood screw or the like with the reinforcing member 68 provided with the screw hole 68A shown in FIG. The case where 60 is supported by the cantilever structure is shown. A weight 64 is attached to the tip of the resonance member 60 to adjust the resonance frequency of the resonance member 60.
As described above, the resonance member 60 is made of copper or a metal plate containing copper, and vibration pickups 66 are mounted at different positions in the longitudinal direction to pick up vibrations having different resonance frequencies, and these signals are received. Mix and output.

  It is suitable as a practice drum for those who intend to become drum players, and is used as an electric drum for drum players.

The top view for demonstrating the structure of the drum head by this invention. Sectional drawing on the AA line shown in FIG. The enlarged plan view for demonstrating the arrangement pattern of the pore formed in the perforated polymer resin film used by this invention. Sectional drawing for demonstrating the Example of the sound reduction drum using the drum head shown in FIG. Sectional drawing for demonstrating the structure which added the snappy to the sound reduction drum shown in FIG. The top view for demonstrating the Example of the snappy used for the Example shown in FIG. The perspective view for demonstrating the tension | tensile_strength adjustment means used for the Example shown in FIG. Sectional drawing for demonstrating the structure which added the vibration pick-up to the sound-reduction drum shown in FIG. The perspective view for demonstrating the structure of the resonance member used for the Example shown in FIG. Sectional drawing for demonstrating the other Example of the resonance member. The perspective view for demonstrating the structure of the resonance member using the Example shown in FIG. Sectional drawing for demonstrating the other Example of the resonance member. Sectional drawing for demonstrating the other Example of the resonance member. The perspective view for demonstrating the structure of the resonance member shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Sound reduction drum head 50 Tension adjustment means 11 Perforated polymer resin film 60 Resonant member 11 'Strip | perforated polymer resin film 61 Longitudinal groove 12 Fine hole 62 Lateral groove 13 Ring 63A-63D Resonance part 20 Trunk 64 Weight 30 Rim 66 Vibration pickup 40 Snappy 41 Support member

Claims (10)

  A sound-reducing drum head that is used while being stretched on one opening end face of a cylindrical body, and this sound-reducing drum head has a perforated height in which fine holes are formed with a density of about 20 to 45%. A sound-reducing drum head comprising a molecular resin film and a ring that supports the periphery of the perforated polymer resin film.   2. The sound-reducing drum head according to claim 1, wherein the pores are arranged in a 60 [deg.] Zigzag pattern.   A sound-reducing drum, wherein the sound-reducing drum head according to claim 1 is stretched around one opening end of a cylindrical body.   4. The sound-reducing drum according to claim 3, wherein the plurality of strip-like polymers are arranged in proximity to the sound-reducing drum head stretched on the drum and are supported in a posture parallel to each other under a predetermined tension. A sound-reducing drum characterized by having a structure provided with a resin film.   The strip polymer resin film according to claim 4 has pores formed at a density of about 20 to 45%, as in the sound-reducing drum head according to claim 1 or 2. Characteristic sound reduction drum.   6. The sound-reducing drum according to claim 3, wherein the sound-reducing drum is mounted on the inner side of the drum, and a part thereof is disposed in contact with a perforated polymer resin film constituting the sound-reducing drum head. And a vibration pickup that converts the vibration of the resonance member into an electric signal.   7. The sound reduction drum according to claim 6, wherein the resonance member includes a substantially rectangular metal plate and a weight attached to one end of the metal plate, and the metal plate has an end to which the weight is not attached. A bent portion on the part side, the free end of the bent portion is attached to the drum body, the bent portion is brought into contact with the back surface of the perforated polymer resin film, and the perforated polymer resin film and A sound-reducing drum characterized in that the structure extends from the contact point to the mounting position of the weight in a direction gradually separating from the back surface of the perforated polymer resin film.   The sound reduction drum according to claim 7, wherein the metal plate constituting the resonance member has a cut in the longitudinal direction and the short side direction, and constitutes a plurality of resonance portions having different resonance frequencies by the cut. A sound reduction drum having a structure in which resonance of each resonance portion is converted into an electric signal by a vibration pickup.   7. The sound reduction drum according to claim 6, wherein the resonance portion is constituted by a substantially rectangular metal plate, and one short side of the metal plate is press-contacted to a joint portion between the perforated polymer resin film and the drum. A first bent portion formed at a predetermined distance from the contact portion to bring the other end of the metal plate closer to the inner wall of the trunk, and a predetermined distance from the first bent portion. A second bent portion for forming the other end of the metal plate as a mounting surface parallel to the inner wall surface of the body, and a portion between the contact portion and the first bent portion. A sound-reducing drum characterized in that a vibration pickup is mounted.   10. The sound reduction drum according to claim 6, wherein the metal plate constituting the resonance member is made of copper or a metal plate containing copper.

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