JPH1129999A - Sound absorbing wall - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sound-absorbing wall which is capable of effectively shutting off the noise in the low and medium sound range and simple in structure by transmitting the vibration of one oscillating plate out of two oscillating plates opposite to each other to the other oscillating plate through a vibration transmission mechanism to mechanically convert the vibration to that of the opposite phase. SOLUTION: Two oscillating plates 2 are mounted on a frame 1 in parallel to constitute a noise absorbing wall. An oscillation link 5 is turnably supported by a fixed point 4 at the center of a support shaft 3. A transmitter hinge-joins a bus link 6 to each end of an oscillation link 5, and joints its tip to a corresponding oscillating plate 2 by a pin 7. The transmitter constitutes a parallel link by two main links and two sub links, and the parallel link may be hinge- joined by pins or integrated with plastic so that a joined part between the links is thin. When the noise arrives at the noise absorbing wall, and the oscillating plate 2 on the sound source side is oscillated, the oscillating plate 2 on the opposite side is oscillated with the opposite phase by the effect of the oscillation link 5. The noise to be leaked on the opposite side of the wall is suppressed to a lower level, and high noise-absorbing effect is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a new type of sound-absorbing wall capable of attenuating low-mid frequency sounds, and more particularly, the present invention relates to low- and mid-frequency sounds. Has an effect of effectively blocking at a high level,
It relates to a sound-absorbing wall that is useful for walls and floors of buildings, sound-absorbing walls in halls, sound-insulating walls along railways and highways, sound-insulating walls in machinery and engine rooms, and mufflers for internal combustion engines. .

[0002]

2. Description of the Related Art Generally, a thick wall made of a material having a large mass is required to cut off a low-pitched sound or a medium-low pitched sound. Conventionally, a concrete wall and a metal such as iron and aluminum are required. Walls provided with a sound absorbing material inside a wall made of steel are often used. However, such a so-called heavy wall has a high manufacturing cost, and requires considerable labor and time for construction. Conventionally, attempts have been made to cut off sound by electrically generating opposite-phase sound.However, this method involves power consumption proportional to the sound volume, the structure of the facility is complicated, and the manufacturing cost is low. There are disadvantages such as high,
It has not been widely used.

[0003]

Under such circumstances, the inventor of the present invention has a simple structure, has no manufacturing cost, and has excellent noise reduction characteristics over a wide frequency band. In particular, as a result of intensive research with the aim of developing a new light-weighted sound-absorbing wall that can effectively cut off low- and mid-range sounds, a completely new sound-absorbing wall described below has been developed. And succeeded in completing the present invention. That is, the present invention is a new type of sound deadening wall having a light structure, having a high sound deadening characteristic in a relatively low frequency band, and in particular, having a function of effectively cutting off low and middle sound at a high level. The purpose is to provide. In addition, the present invention relates to the wall and floor of a building,
It aims to provide sound-absorbing walls in halls, noise barriers along railways and highways, noise barriers in machinery and engine rooms, and silencing walls (mufflers) for internal combustion engines that have a light structure. is there. A further object of the present invention is to provide a sound-absorbing wall having a light structure which has a simple structure, requires no manufacturing cost, and can be installed in a short period of time.

[0004]

The present invention for solving the above problems comprises the following technical means. (1) A light-weighted sound-absorbing wall having high sound-absorbing characteristics in a relatively low frequency band, at least the following members: (a) two opposing diaphragms, and (b) a frame for fixing the diaphragms And (c) a mechanical type anti-phase vibration transmitting mechanism for connecting these diaphragms, wherein the vibration transmitting mechanism mechanically reduces the vibration of one of the vibrating plates that receives a sound and vibrates. The vibration of the opposite phase is transmitted to the other diaphragm, and the other diaphragm is simultaneously displaced and vibrated inward or outward with the one diaphragm by the vibration energy of the original sound. The sound deadening wall according to the above. (2) The vibration transmission mechanism according to the above (1), wherein the vibration transmission mechanism has a transmitter rotatably supported at a fixed point between the two diaphragms at an intermediate portion thereof, and each end of which is joined to the corresponding diaphragm. Noise barrier. (3) the above-mentioned transducer comprises a swing link and a sub-link,
An oscillating link is rotatably supported at a fixed point between the two diaphragms at an intermediate portion thereof, and a sub-link is hinged to both ends of the oscillating link, and each end of the sub-link is joined to a corresponding diaphragm. The silencing wall according to (2) above. (4) The sub-link is formed of a linear body, and both ends of the swing link are connected to the corresponding diaphragms by the linear body, and the swing link is rotationally urged by a bias spring to urge the swing line. The sound-absorbing wall according to (3), wherein tension is applied to the body. (5) The frame body is composed of a grid having a plurality of sections, and the diaphragm is fixed to both sides of the grid to form two opposing diaphragms for each section, and the vibration transmitting mechanism is configured of one of the grids. The sound deadening wall according to (1) or (2), wherein one diaphragm in one section is connected to the other diaphragm in an adjacent section. (6) At least two sub-links, each end of which is hinged to each other, each end of which is joined to a corresponding diaphragm, and at least two main links, each end of which is hinge-joined to the corresponding sub-link. (2) The sound deadening wall according to (2) above, wherein the main link and the sub link cooperate to form a parallel link. (7) The sound deadening wall according to the above (1) or (2), wherein two diaphragms are formed in a trumpet shape, and the two diaphragms are attached to opening portions on both sides of a box whose center is partitioned by a partition plate. (8) The vibration transmission mechanism is composed of two sets of piston cylinders filled with fluid, and the pistons fitted in each cylinder are connected to the corresponding diaphragm, and when one piston moves, the other piston moves. The sound deadening wall according to (1), wherein the two cylinders communicate with each other so as to move in opposite directions. (9) A light-weight silencing wall having high silencing characteristics in a relatively low frequency band, which rotatably supports each side edge of two diaphragms on a support shaft, and further sandwiches the support shaft. The sound deadening wall according to claim 1, wherein a diaphragm moving integrally with these diaphragms is extended on the opposite side, and a partition plate is formed between said two diaphragms as necessary.

[0005]

Next, the present invention will be described in more detail. The sound deadening wall of the present invention basically has two opposing
A vibration plate, a frame body for fixing the vibration plate, and a mechanical anti-phase vibration transmission mechanism (sometimes referred to as a vibration transmission mechanism in this specification) for connecting the vibration plates. It becomes. The vibration transmission mechanism mechanically converts the vibration of one of the vibration plates that receives the sound into vibration of the opposite phase and transmits the vibration to the other vibration plate, and transmits the other vibration energy to the vibration energy of the original sound. The greatest feature is that it is configured to be displaced and vibrated inward or outward simultaneously with one of the diaphragms. This vibration transmission mechanism has a function of, when one of the diaphragms facing the sound source receives a sound and vibrates, to mechanically change the vibration to an opposite phase and transmit the vibration to the other diaphragm. By using the above-mentioned vibration transmission mechanism, the sound that has passed through the diaphragm on the sound source side and the sound that is generated by the vibration of the diaphragm on the opposite side of the sound source can be made in opposite phases, so that their mutual canceling action is achieved. As a result, a remarkable silencing effect can be obtained.

[0006] The sound deadening wall of the present invention has high sound deadening characteristics in a relatively low frequency band, and exhibits a remarkable sound deadening effect particularly on low and middle sounds in which large vibrations occur. As the sound becomes higher, the amplitude of the diaphragm becomes smaller even with sound of the same intensity, so that the noise reduction performance is reduced accordingly. Further, as the sound becomes higher, that is, as the wavelength becomes smaller, the interval between the two diaphragms cannot be ignored. That is, even if the vibrations of the two diaphragms have a phase shift of 180 degrees, the sound that has passed through one of the diaphragms is out of phase by that amount while reaching the other diaphragm. The noise reduction performance is reduced. Therefore, in the present invention, the interval between the two diaphragms needs to be sufficiently smaller than the wavelength of the sound to be silenced, whereby the silencing effect can be obtained even in a high frequency band. . Further, in order to improve the sound deadening characteristics for higher frequency sounds, it is necessary to reduce the weight of the diaphragm so that even higher sounds can be vibrated. It is necessary to reduce the weight so that it can cope with the vibration frequency.

[0007] The two diaphragms used for the sound deadening wall of the present invention do not need to be made of a heavy material such as concrete or iron plate. For example, plywood, plastic plate, paper, plastic film, thin aluminum plate Light materials such as a lightweight metal plate or a composite material made of these materials can be used as appropriate. The two diaphragms may not be the same material, and the above materials may be used in combination as appropriate. Further, one of the two diaphragms may be the heavy material,
It is also possible to use the other light material as appropriate.

The vibration transmission mechanism used for the sound deadening wall of the present invention has a structure in which two opposing diaphragms are mechanically connected, and one of the diaphragms receives sound. In the process of displacing and vibrating in and out, when one diaphragm moves inward, the other diaphragm moves inward, and in the process of moving outward, the other diaphragm moves outward. Features.

The above-mentioned vibration transmitting mechanism (hereinafter sometimes referred to as a silencing mechanism) may have a function of mechanically changing the vibration of one diaphragm to an opposite phase and transmitting it to the other diaphragm. Any structure may be used, and the structure is not particularly limited. As a typical example of the vibration transmission mechanism, for example, a device (hereinafter referred to as a “transducer”) that is rotatably supported in the middle at a fixed point between two vibration plates and each end is joined to the corresponding vibration plate. ) Is a preferred example. In this case, in addition to the above components, it is possible to use appropriate members as accessory devices. This transmitter has a function of, when one of the diaphragms vibrates in response to a sound, swinging in response to the vibration and transmitting the vibration to the other diaphragm. Since this transducer is rotatably supported at a fixed point in the middle, the movement of each end is reversed in phase. Therefore, the diaphragm on the side opposite to the sound source is shaken by the above-described transducer in a phase opposite to that of the diaphragm on the sound source side, and a high noise reduction effect is achieved by a canceling action between a sound generated from the diaphragm and a sound passing through the wall. can get.

The above-mentioned transmission element may be directly joined to the diaphragm, or a sub-link may be provided between the transmission element and the transmission element may be constituted by a swing link and a sub-link.
That is, the sub link is hinged to both ends of the swing link with pins or the like, and each end of the sub link is connected to the corresponding diaphragm. By providing the sub-links in this way, it is possible to position the joint between the transmitter and the two diaphragms on the same straight line perpendicular to the diaphragm. In this case, since the vibration modes of the two diaphragms are just reversed, a remarkable noise reduction effect can be obtained.

In place of such a sub-link, both ends of the swing link and the diaphragm are connected by a striated body, and the swing link is urged to rotate by a bias spring to apply tension to the striated body. You can do so. This means is useful especially when the diaphragm is thin and tends to sag, because the slack of the diaphragm can be removed by the bias spring.

Further, the transmitting element may be constituted by a parallel link. That is, as the parallel link, for example, at least two main links hinged to each other with a pin or the like, each end of which is joined to a corresponding diaphragm, and rotatably supported at a fixed point between the two diaphragms Preferred examples include at least two sub-links, each of which is hinged at the end of the corresponding main link, and these main and sub-links cooperate to form a parallel link. . By employing such a parallel link structure, the position of the junction between the transducer and the two diaphragms can be located on the same straight line perpendicular to the diaphragm. In this case, since the vibration modes of the two diaphragms are just reversed, a remarkable noise reduction effect can be obtained.

Further, a vibration transmission mechanism is provided with a fluid (liquid,
It is also possible to combine two sets of piston cylinders filled with gas. The two cylinders are connected such that when one piston moves, the other piston moves in the opposite direction. Thereby, the same silencing effect can be obtained.

Next, the shape and structure of the diaphragm can be appropriately changed according to the purpose of use and the like, and are not particularly limited. For example, the diaphragm may be formed like a cone paper of a speaker. It is also possible to suitably form a trumpet shape and attach it to the opening on both sides of a box whose center is partitioned by a partition plate. By adopting such a configuration,
Since the box stabilizes the vibration of the trumpet-shaped diaphragm, and in particular, can effectively reproduce low-pitched bass,
A high silencing effect can be obtained for sounds in the low range.

Next, the combination of the diaphragm, the frame, and the vibration transmitting mechanism can be appropriately changed according to the purpose of use. Also, the shape and structure of the frame are not particularly limited, for example, by stretching a diaphragm made of a film on both sides of a lattice or lattice having a plurality of sections,
It is also possible to appropriately form two opposing diaphragms for each section. In this case, the vibration transmission mechanism may have a structure in which one diaphragm of one section of the lattice and the other diaphragm of the next section are connected through a hole formed in a partition of the lattice. According to this method, a large number of vibration transmission mechanisms can be incorporated in one noise reduction wall, so that a high level of noise reduction effect can be obtained. Further, since each vibration transmission mechanism can be directly supported by the lattice, the structure can be simplified, and the silencing mechanism can be easily standardized and unitized, and the manufacturing cost can be reduced.

Next, other than the above, for example, a light-weighted sound-absorbing wall having a high sound-absorbing characteristic in a relatively low frequency band, and each side edge of the two diaphragms is rotatably mounted on a support shaft. Further, a diaphragm that moves integrally with these diaphragms is extended on the opposite side of the support shaft, and a partition plate is formed between the two diaphragms as necessary. Sound-absorbing wall. This is because, when the diaphragm on the sound source side vibrates, the diaphragms on the opposite side vibrate in opposite phases and exert mutual noise-reduction effects, and a high noise-reduction effect is expected despite the simple structure. be able to.

In the present invention, the above two diaphragms can be used as they are, but if necessary, in order to protect the surface of the diaphragm, the diaphragm is protected by a suitable means such as a protective plate or a protective wire net. A member can be attached. As the protective member, for example, a wooden or metal plate, a gypsum panel, a building outer wall material, or a composite material thereof is exemplified. Further, in the present invention, a partition plate of an appropriate form can be provided between the two diaphragms. As the partition plate,
Suitable examples include a plate made of resin such as wood, metal, rubber, and plastic, or a material obtained by attaching a sound absorbing material such as sponge to these, but not limited thereto, and an appropriate material may be used. Can be. By providing the partition plate, sound in a high frequency band can be muted. Next, a mode of using the sound deadening wall of the present invention will be described. The sound deadening wall of the present invention is suitably used, for example, as a partition wall of a building. In this case, the sound deadening wall is, for example, installed between the floor of the room on one floor and the ceiling of the room on the floor below, but is not limited to this, and the floor and the ceiling are connected to two diaphragms. It can be installed in any suitable form, such as in the form of a wall, or similarly in the form of a wall-to-wall connection. In this case, one and / or the other of the two diaphragms may be constituted by part or all of the wall material / floor material. This can prevent, for example, footsteps in a low frequency band on the floor from reverberating on the floor below. The sound deadening wall of the present invention is used, for example, as a partition / wall around a sound source. A conventional concrete wall completely surrounds a sound source or a space to be sound-proofed, and is characterized in that the sound is silenced by a method of stopping sound. Therefore, if there is a gap in the wall, the soundproofing effect is significantly reduced. The sound-absorbing wall of the present invention does not bind the sound but cancels the sound that is going to pass through the wall with the opposite-phase sound.Therefore, there is no need to surround the sound source, for example, around the noise source. By simply setting it up like a screen, a remarkable noise reduction effect can be obtained. In addition, the sound insulation walls of conventional heavy structures such as concrete suppress the vibration of sound by mass.However, if the area of the wall receiving the sound is large, the vibration of the sound is easy to be transmitted. A further increase in thickness is required.
The sound deadening wall of the present invention can be suitably used even for a large-area wall because the sound deadening effect does not decrease even if the wall area receiving the sound becomes large. As described above, the light-weight sound-absorbing wall of the present invention has a simple structure, requires no manufacturing cost, and can be installed in a short period of time. The sound-absorbing wall of the present invention includes, for example, partition walls and floors of buildings, sound-absorbing walls of halls, soundproof walls along roads and railways,
It is useful as a soundproofing wall in the engine room of machinery and vehicles, and as a soundproofing wall of a muffler (muffler) for internal combustion engines. The sound deadening wall of the present invention has the greatest feature in having the above sound deadening mechanism, and if the sound deadening mechanism is used,
Regardless of the type of the product, it is included in the scope of the present invention.

[0018]

EXAMPLES Next, the excellent noise reduction characteristics of the noise reduction wall of the present invention will be described with reference to test examples. Test Example (1) Method As a sound deadening wall, a sound deadening wall (with a unit) provided with a sound deadening mechanism shown in FIG. 6 described later was used. The frame was made of wood, and the diaphragm was a wood rack having a thickness of 2 mm (paper board with urethane interposed therebetween). A sound of 100 dB emitted from the oscillator was passed from a speaker located on one side of the sound deadening wall, and the transmitted sound (sound pressure level) was measured by a measuring instrument located 50 cm on the opposite side of the sound deadening wall, and its sound deadening characteristics were investigated. . As a control, a test was performed in the same manner as described above except that a frame and a diaphragm only (without a unit) which did not include the silencing mechanism of the present invention were used.

(2) Results The results are shown in FIG. 25 (sine wave), FIG. 26 (sawtooth wave) and FIG. 27 (pulse wave). In the drawing, A indicates that there is a unit, and B indicates that there is no unit. As shown in these figures, when the sound deadening wall of the present invention is used, the sound of 100 dB emitted from the oscillation device is 50 Hz to 2 Hz.
13dB to 25dB in the low frequency band of about 00Hz
Attenuation of the sound pressure level was observed. This means that the energy of the transmitted sound has been attenuated to 1/20 to 1/300 as the energy of the sound. On the other hand, when there is no unit, 100
The dB sound hardly attenuated and reached the measuring instrument. From the above results, it was confirmed that when the sound deadening wall of the present invention was used, a low tone of 50 Hz to 200 Hz of 100 dB could be attenuated to 1/20 to 1/300. In addition, when similar tests were performed on other examples described later, almost the same results were obtained.

Next, embodiments of the present invention will be specifically described with reference to the drawings. However, the present invention is not limited to the following embodiments. 1 to 4 show an embodiment in which a transmission element, which is a preferred example of a vibration transmission mechanism, is a constituent element, and an embodiment in which the transmission element includes a swing link and a sub-link. First, referring to FIGS. 1 and 2, two diaphragms (plywood panels) 2 are attached to the frame 1 in parallel to form a wall. A support shaft 3 is provided between these diaphragms.
And a swing link 5 is rotatably supported at a fixed point 4 at the center of the support shaft so that the swing link can rotate around the support shaft. The sub-links 6 are hinged to both ends of the swing link, respectively, and each end of the sub-link is joined to the corresponding diaphragm 2 with a pin 7.

Next, the operation of the sound deadening wall will be described. FIG.
Shows a case where a relatively low sound having a wavelength approximately equal to the length of the diaphragm 2 arrives at the sound deadening wall. When the sound hits the left diaphragm 2a, the diaphragm 2a resonates. This vibration is transmitted to the swing link 5, and the swing link vibrates back and forth around the fulcrum 8 to vibrate the right diaphragm 2b.

That is, first, as shown in FIG. 3 (a), when the left diaphragm 2a meets the air-dense part, the left diaphragm 2a bends outward. As a result, the lower end of the oscillating link 5 is pulled, so that the oscillating link 5 rotates clockwise about the fulcrum 8, and is pushed by the upper end of the oscillating link, whereby the right diaphragm 2b bends outward. .

Next, as shown in FIG. 3 (b), when the left diaphragm 2a meets a dense portion of air, the left diaphragm 2a bends inward. As a result, the lower end of the swing link 5 is pushed, so that the swing link 5 rotates counterclockwise about the fulcrum 8. As a result, the upper end of the swing link is retracted,
The right diaphragm 2b also bends inward.

As described above, when the vibration plate 2a on the sound source side vibrates, the vibration plate 2b on the opposite side vibrates due to the function of the swing link, and furthermore, it is understood that the vibration plate 2b vibrates in the opposite phase. When the left diaphragm 2b vibrates, a sound is generated. This left diaphragm 2
The sound emitted by b has a phase opposite to that of the sound passing through the right diaphragm 2a, and the sound leaking to the opposite side of the wall is suppressed to a sufficiently small level by the mutual canceling action of the two, and the sound is high. A silencing effect is obtained.

FIG. 4 shows another embodiment of the transmitter. The sub-link 62 is hinged to both ends of the linear swing link 60 using pins 61. The center of the swing link 60 is rotatably supported on a support (not shown) by a pin 63. The tip of the sub-link 62 is joined to the inner surfaces of the corresponding diaphragms 2a, 2b with pins 65. The three pins 63, 65, 65 are located on the same straight line perpendicular to the diaphragm 2.

With this structure, when a sound is received and, for example, the right diaphragm 2a bends inward, the upper end is pushed via the right sub-link and the swing link 60 rotates counterclockwise. Move. As a result, the left sub-link is pulled, and the left diaphragm 2b also bends inward. On the other hand, when the right diaphragm 2a is displaced outward, the upper end of the swing link is pulled through the right sub-link, and the swing link rotates clockwise, via the left sub-link. The left diaphragm 2b is also displaced outward. Thus, when the diaphragm on the sound source side vibrates, the diaphragm on the opposite side vibrates in the opposite phase. In this example, the action points (pins 65, 65) of the transmitter are located on the same straight line. Therefore, the left and right diaphragms are in the same mode (the phases are different)
, And the noise reduction effect is improved.

FIG. 5 shows another embodiment of the transducer. FIG.
As in the case of (1), the swing link 70 is rotatably supported on a support column (not shown) by a pin 71. Both ends of the swing link 70 are connected to the corresponding diaphragm by a striated body 72. As the striatum, a material having a small elongation, for example, a metal wire is exemplified as a preferable material. A bias spring (tension coil spring) 73 is attached between the swing link 70 and one diaphragm. The force of this spring tensions both filaments 72 and deflects the two diaphragms slightly inward within the limits of elasticity.

With such a configuration, when the right diaphragm 2a is bent inward by receiving a sound, for example, the swing link 70
Rotates counterclockwise, the left striated body is pulled, and the left diaphragm 2b is also displaced inward. Conversely, when the right diaphragm 2a moves outward, the swing link 70 rotates clockwise, the left striatum loosens, and the left diaphragm 2b moves outward with its own elastic force. Is displaced. In this manner, when one of the two vibration plates vibrates, the other vibrates in the opposite phase, and the same silencing effect as described above can be obtained.

FIGS. 6 to 11 show an embodiment of a sound-absorbing wall having a lattice structure having a plurality of sections. A plastic film film is stretched on both sides of the lattice 101 to form two opposing diaphragms 102 in each section, and the transducer is constituted by a swing link 105 and a sub-link 106, and one side of one section This diaphragm 102a is connected to the diaphragm 102b on the opposite side of another section adjacent to the other diaphragm 102a. The swing link has an S-shape, passes through a hole 109 formed in the lattice, and is rotatably supported at its center on a support shaft 103. Each end of the sub-link 106 is joined to the corresponding diaphragm with a pin 107. Preferred examples of the sound deadening wall include one in which one transmission element is supported on a support shaft (FIGS. 6 to 8) and one in which two transmission elements are supported on a support shaft (FIGS. 9 to 11). In these sound deadening walls, the vibrations of the diaphragms in each section are transmitted to the diaphragm on the opposite side of the adjacent section in opposite phases (FIGS. 8 and 1).
1) There is an advantage that a high silencing effect can be obtained and that the silencing mechanism used in the present invention can be easily unitized.
The operation of these sound deadening walls (FIGS. 8 and 11) is the same as in the case of FIG. 3 described above, and a description thereof will be omitted.

FIG. 12 shows another embodiment of a sound-absorbing wall having a lattice structure. This is one in which the vibration transmission mechanism is constituted only by the transmission element. The grid 90 is composed of vertical and horizontal members, and a plastic film is stretched on the grid 90 to form the diaphragm 22. The transmission element 91 has an S-shape, passes through a hole 92 formed in the lattice 90, and has a central portion rotatably supported by the lattice 90. Each end of the transmission element 91 corresponds to the corresponding diaphragm 2
2 are directly joined. Also in this noise reduction wall, the vibration of the diaphragm in each section is transmitted to the diaphragm on the opposite side of the adjacent section in the opposite phase, and a high noise reduction effect is obtained.

FIGS. 13 to 16 show still another embodiment of the transducer. In FIG. 14A, the transducer is a main link 8
0 and a sub-link 81, each of which constitutes a parallel link. The two main links 80 are hinged to each other by a pin 82, and their ends are connected to the corresponding diaphragm 2 by a pin 83. Reference numeral 84 denotes a support shaft provided between the two vibration plates, and the two support shafts 81 rotatably support the two auxiliary links 81, respectively. The tip of the sub link 81 is hinged to the center of the corresponding main link 80 with a pin 85.

Next, the operation of the transmitter will be described. In this embodiment, when a sound is received and, for example, the right diaphragm 2a moves inward, the angle of the two main links 80 becomes narrower as shown by a chain line in the figure, and the left diaphragm 2b also moves inward. Move. On the contrary, when the right diaphragm 2a moves outward,
The angle of the two main links increases, and the left diaphragm 2b is also displaced outward. In this way, both diaphragms vibrate in opposite phases and exhibit a sound-muffling effect.

FIG. 14B shows an example in which the same thing as described above is integrally formed of plastic. In this embodiment, the link portion between the links is formed with a small thickness, and is easily bent at this portion, so that it functions in the same manner as when it is joined with a pin. In addition, as shown by a chain line in the figure,
By combining two of the same shape, the whole can be formed into four parallel links. 13, 15 and 16 show the embodiment. The configuration and operation of these sound deadening walls are the same as in the above-described case, and will not be described.

FIGS. 17 to 19 show another embodiment of a sound-absorbing wall having a lattice structure. As shown in FIG. 17 and FIG.
Reference numeral 1 denotes a combination of a large number of cylindrical bodies. A plastic film is provided on both sides of the lattice 21 to form two opposing diaphragms 22 for each section. Each cylinder 21 is provided with a small hole 23 for venting air.

Two cylindrical sections are formed as one set, and a hole 24 is formed in a partition between them, and two swing links 25 are formed in the hole.
Through this, each swing link is rotatably supported by the partition. Each end of the oscillating link 25 has two diaphragms 2
2 are connected by a striated body 26 (FIGS. 18 and 19). Then, each swing link is rotationally urged by a bias spring 27 so that the filament 26 becomes taut.

Next, the operation of the sound deadening wall will be described. In this embodiment, when sound is received and the vibration plates 22aa and 22ab on the sound source side (the side indicated by the arrow in FIG. 18) vibrate, the vibration is transmitted to the swing link 25 via the linear body 26.
a, 25b. The vibration of the oscillating link is transmitted to the diaphragm 22b on the opposite side of the sound source through the striated body 26 on the opposite side.
a, 22bb.

In this example, the swing link 25 and the striated body 26
Cooperate with each other to perform the same operation as the swing link 6 in FIG. 1, and the vibration of the diaphragm 22aa is transmitted to the diaphragm 22bb.
The vibrations of the vibration plate 22ab are transmitted to the vibration plate 22ba with their phases reversed. Therefore, the sound transmitted through the diaphragm 22a on the sound source side cancels each other out of phase with the sound generated by the diaphragm 22b on the opposite side, and a noise reduction effect is obtained.

FIG. 20 shows an embodiment configured as a speaker box type. A trumpet-shaped diaphragm (cone paper) 12 supported by a dome-shaped frame 14 is attached to each side of the box 11. A partition plate 13 is provided in the center of the box, and two swing links 16 and two sub-links, which are the same transmitters as in FIG. Both ends of the swing link are fixed to the diaphragm 12 with pins.

The operation of the sound deadening wall is the same as that described above. When the diaphragm 12 on the sound source side vibrates, the swing link 6
Then, the diaphragm 12 on the opposite side vibrates in the opposite phase via the diaphragm, and the sound that has passed through the diaphragm on the sound source side and the sound generated by the diaphragm on the opposite side cancel each other, and a noise reduction effect is obtained.

In this embodiment, the box 11 and the partition 13
However, a dedicated box is formed for each diaphragm, and this stabilizes the vibration of the trumpet-shaped diaphragm 12,
In particular, there is an effect of effectively reproducing a low-pitched sound having an opposite phase.

FIG. 21 shows an embodiment of a vibration transmission mechanism using a piston cylinder. The two diaphragms 42 are attached to the frame 41 at intervals. A column 43 is erected in the center of the frame, and two cylinders 44 are attached to the column in a lateral direction. Both cylinders are connected by a pipe 46, and the inside is filled with a working liquid. Each cylinder is fitted with a piston 45, and each piston is connected to a corresponding diaphragm. The upper and lower cylinders are mounted in opposite directions. When the diaphragm on the sound source vibrates, the vibration is transmitted through the corresponding piston, working fluid, and the other piston,
It is transmitted to the other diaphragm. Since the directions of the upper and lower cylinders are reversed, the other diaphragm vibrates in a phase opposite to that of the diaphragm on the sound source side, and a silencing effect can be obtained as in the case of the above embodiment.

FIGS. 22 to 24 show a rotary panel type embodiment. As shown in FIGS. 22 and 23, a column 33 is erected at the center of the frame 31, and several cylinders 34 are rotatably supported on the column. As shown in FIG.
5 extend in the opposite direction, and a diaphragm (panel) 32 is attached using this arm. There are a total of four diaphragms, with the diaphragm 32bb on the opposite side of the diaphragm 32aa across the support 33, and the diaphragm 32ba on the opposite side of the diaphragm 32ab.
Are respectively extended. These diaphragms are supported
Attached so that it can rotate around. A partition plate 36 is provided between the diaphragms to prevent interference, and the periphery thereof is fixed to the frame 31.

Next, the operation of the sound deadening wall will be described. In FIG. 22, when a low sound arrives from the direction of the arrow, the sound hits the diaphragms 32aa and 32ab, and these diaphragms vibrate around the column 33 as shown by a chain line in the figure. When the diaphragm 33aa vibrates, the diaphragm 33bb connected thereto also vibrates. Similarly, when the diaphragm 33ab vibrates, the diaphragm 33ba also vibrates. The diaphragms 32ba and 32bb on the side opposite to the sound source vibrate in the opposite phase to the diaphragms 32aa and 32ab on the sound source side, and a silencing effect can be obtained as in the above embodiment.

[0044]

As described in detail above, according to the present invention,
The following effects can be obtained. (1) A sound deadening wall having high sound deadening characteristics in a relatively low frequency band can be obtained. (2) A new type of sound deadening wall having a light structure and having an effect of effectively blocking low and middle sounds at a high level can be obtained. (3) Sound-absorbing walls that are useful for walls and floors of buildings, sound-absorbing walls in halls, sound-insulating walls along railways and highways, machinery and engine rooms, and sound-insulating walls for silencers (mufflers) for internal combustion engines. Can be provided. (4) Simple structure, low manufacturing cost, and
It is possible to provide a light-weight sound-absorbing wall that can be installed in a short period of construction. (5) It is easy to unitize and standardize the noise reduction mechanism, and it is easy to mass produce a noise reduction wall incorporating the unit. (6) Due to the unitization, the unit can be easily incorporated into a building or other products.

[Brief description of the drawings]

FIG. 1 is a perspective view showing one embodiment (a swing link and a sub-link structure) of a sound deadening wall according to the present invention.

FIG. 2 is a sectional view of FIG.

FIG. 3 is an explanatory view showing the operation of the sound deadening wall in FIG. 1;

FIG. 4 is a sectional view showing another embodiment of the sound deadening wall of the present invention.

FIG. 5 is a cross-sectional view showing another embodiment (swing link and striated body structure) of the sound deadening wall of the present invention.

FIG. 6 is a perspective view showing another embodiment (lattice structure) of the sound deadening wall of the present invention.

FIG. 7 is a sectional view of FIG. 6;

FIG. 8 is an explanatory view showing the operation of the sound deadening wall in FIG. 6;

FIG. 9 is a sectional view showing another embodiment (lattice structure) of the sound deadening wall of the present invention.

FIG. 10 is a sectional view of FIG. 9;

FIG. 11 is an explanatory view showing the operation of the sound deadening wall of FIG. 9;

FIG. 12 is a perspective view showing another embodiment (lattice structure) of the sound deadening wall of the present invention.

FIG. 13 is a perspective view showing another embodiment (parallel link structure) of the sound deadening wall of the present invention.

FIG. 14 is a sectional view showing a detailed structure of a parallel link.

FIG. 15 is a sectional view of FIG.

FIG. 16 is an explanatory diagram showing the operation of the sound deadening wall in FIG. 12;

FIG. 17 shows another embodiment of the sound deadening wall of the present invention (lattice structure).
FIG.

FIG. 18 is a sectional view of the sound deadening wall of FIG. 17;

FIG. 19 is a perspective view of the sound deadening wall of FIG. 17;

FIG. 20 is a cross-sectional view showing another embodiment (horn type structure) of the sound deadening wall of the present invention.

FIG. 21 is a sectional view showing another embodiment of the vibration transmission mechanism.

FIG. 22 is a horizontal sectional view of another sound deadening wall (rotating panel type) of the present invention.

FIG. 23 is a perspective view of the sound deadening wall of FIG. 22;

FIG. 24 is an enlarged view of a main part of FIG. 23;

FIG. 25 shows a measurement result of a sound pressure level (sine wave) in a test example.

FIG. 26 shows a measurement result of a sound pressure level (sawtooth wave) in a test example.

FIG. 27 shows a measurement result of a sound pressure level (pulse wave) in a test example.

[Explanation of symbols]

 2 Vibrating plate 3 Support shaft 5 Swing link 6 Secondary link 11 Box 12 Vibrating plate 13 Partition plate 16 Swing link 21 Lattice 22 Vibrating plate 24 Hole 25 Swing link 26 Linear body 27 Spring 32 Vibrating plate 33 Post 42 Vibration Plate 44 Cylinder 45 Piston 60 Swing link 62 Secondary link 70 Swing link 72 Striatal body 80 Main link 81 Secondary link 90 Lattice 91 Transmitter 92 Hole 101 Lattice 102 Vibrating plate 103 Support shaft 105 Swing link 106 Secondary link

Claims (9)

[Claims] 1. A light-weight silencing wall having high silencing characteristics in a relatively low frequency band, comprising at least the following members: (a) two opposing diaphragms, and (b) fixing the diaphragms And (c) a mechanical type anti-phase vibration transmission mechanism for connecting these diaphragms, wherein the vibration transmission mechanism mechanically converts the vibration of one of the diaphragms vibrating in response to a sound. The other diaphragm is transmitted to the other diaphragm by changing the vibration to the opposite phase, and the other diaphragm is simultaneously displaced or vibrated inward or outward with one diaphragm by the vibration energy of the original sound. The noise-absorbing wall described above. 2. A vibration transmission mechanism comprising a device (transmitter) rotatably supported at a fixed point between two diaphragms at an intermediate portion thereof and having each end joined to a corresponding diaphragm. The sound deadening wall according to claim 1. 3. The oscillating link includes a swing link and a sub-link, and the swing link is rotatably supported at a fixed point between the two diaphragms at an intermediate portion thereof. 3. The sound deadening wall according to claim 2, wherein each of the sub-links is hinged, and each end of the sub-link is joined to a corresponding diaphragm. 4. The sub-link comprises a striated body, and both ends of the oscillating link and corresponding diaphragms are connected by the striated body.
4. The sound deadening wall according to claim 3, wherein said swing link is rotationally biased by a bias spring to apply tension to said filament. 5. The frame body is composed of a grid having a plurality of sections, and a diaphragm is fixed to both sides of the grid to form two opposing diaphragms for each section, and the vibration transmitting mechanism comprises a grid. 3. The sound deadening wall according to claim 1, wherein one diaphragm in one section is connected to the other diaphragm in an adjacent section. 6. The at least two sub-links, each end of which is hinged to each other and joined to a corresponding diaphragm, and at least two sub-links each of which is hinged at one end of the corresponding sub-link. The noise reduction wall according to claim 2, wherein the main link and the sub link cooperate to form a parallel link. 7. The sound deadening wall according to claim 1, wherein the two diaphragms are formed in a trumpet shape, and the two diaphragms are attached to opening portions on both sides of a box whose center is partitioned by a partition plate. 8. A vibration transmitting mechanism includes two sets of piston cylinders, each of which is filled with a fluid, and a piston fitted to each cylinder is connected to a corresponding diaphragm, and when one piston moves, the other piston moves. The noise reduction wall according to claim 1, wherein the two cylinders communicate with each other so that the piston moves in the opposite direction. 9. A light-weight silencing wall having a high noise-damping characteristic in a relatively low frequency band, wherein each side edge of two diaphragms is rotatably supported on a support shaft, and the support shaft is further provided with the support shaft. The diaphragm that moves integrally with these diaphragms is extended on the opposite side with
The sound deadening wall according to claim 1, wherein a partition plate is formed between the two diaphragms as necessary.