JP3478766B2 - Anti-vibration support structure for soundproof wall - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an anti-vibration support structure for a soundproof wall, and more particularly, to a soundproof wall for preventing noise from being transmitted to the outside in a structure containing a noise and vibration source inside. It relates to an anti-vibration support structure.

[0002]

2. Description of the Related Art In the conventional vibration isolating support structure for a soundproof wall, as shown in FIG. 11, for example, a soundproof wall 1 has a mounting metal member 10 attached to the inner surface thereof on a projecting portion 8a of the building 8. The fastening member 11 was used to fasten it via a vibration-proof material 12 made of a vibration-proof rubber.

[0003]

The above-mentioned conventional antivibration support structure is mainly intended to shield noise from the inside or the outside of the building 8 such as a factory, and the soundproof wall 1 and the building 8. When a relative vibration occurs between the constructions, the support structure is mainly intended to protect the mounting member between the building 8 and the soundproof wall 1 from being damaged. That is, the main purpose is to block the transmission of sound waves from the sound source, and as shown in FIG.
The soundproof wall 1 is elastically supported by the structure 8 in the vertical direction along the direction. Inside the building 8 such as the factory,
Usually, a plurality of noise and vibration sources are accommodated, and the noise and vibration sources are, for example, a roots blower and an air compressor. The illustrated structure 8 is an existing factory, and the roots blower, the air compressor, etc., which are the sources of the noise and vibration, are installed on the floor surface, and the space between the base of these devices and the floor surface is protected. Only a vibration-proof material such as vibration rubber is interposed.

Therefore, it is not sufficient as a measure to prevent the vibration transmission between the noise and vibration source and the body of the structure 8, and the transmission of the vibration from the vibration source to the body is almost suppressed. First, the structure 8 and the soundproof wall 1
Even if the vibration transmitted from the skeleton to the soundproof wall 1 is somewhat attenuated by the elastic support between and, the vibration of the skeleton in the direction perpendicular to the surface of the soundproof wall 1 is transmitted to the soundproof wall 1. Even if the sound waves transmitted from the noise and vibration sources to the outside of the building 8 can be blocked, the soundproof wall 1 itself receives the vibrations from the vibration sources and vibrates. It is the next source of noise.

Therefore, in the structure 8 containing the noise and vibration sources inside as described above, the conventional vibration isolation support structure of the soundproof wall may not be sufficient noise prevention measures. Is the current situation. That is, the conventional anti-vibration support structure for the soundproof wall generally does not consider that the soundproof wall itself is a secondary source of noise.

Therefore, an object of the present invention is to simplify the mounting structure of the soundproof wall, to enable the retrofitting work, and to prevent the secondary noise radiation from the soundproof wall itself to prevent the noise from the outside. The point is to provide a vibration-proof support structure for a soundproof wall that can reliably suppress the noise.

[0007]

Means for Solving the Problems [Characteristic Configuration of the Present Invention] The first characteristic configuration of the vibration-damping support structure for a soundproof wall according to the present invention is as follows.
A structure for accommodating a source of noise and vibration inside, as claimed in claim 1, wherein the structure and the soundproof wall are vibration-proof support structures for preventing noise from the structure to the outside. An elastic support mechanism is provided between the sound insulation panel to be formed and a relative vibration of the sound insulation panel and a load of the sound insulation panel is received by a pair of elastic members so as to damp the relative vibration. The panel is supported on the construct through the elastic support mechanism, and the elastic support mechanism is configured by attaching the panel to the upward surface of the construct.
A base portion provided with a mounting surface to be attached, and the sound insulation panel
The support surface that supports the downward surface of the support member attached to
And a pair of elastic members integrally provided,
A pair of elastic material holding slopes are provided on the base body in opposite directions.
The support portion is provided symmetrically so as to be inclined.
The one parallel to for each of the pair of elastic material holding Slope
The pair of elastic support slopes are provided symmetrically, and the elastic members are
The elastic member holding slope and the elastic support that face each other in parallel.
The mounting surface is constructed by interposing on each of the sloped surfaces
It is attached to the upward surface of the object and is supported by the supporting surface.
An elastic support member provided so that each of the pair of elastic members is compression-deformed in an oblique direction symmetrical with respect to the vertical axis by the load of the sound insulation panel while supporting the downward surface of the member. /> There is a point.

Second aspect of the vibration-proof support structure for a soundproof wall according to the present invention
According to a second aspect of the present invention, there is provided a characteristic configuration according to the first characteristic configuration, in which the pair of elastic members are arranged side by side in a vertical direction in a direction orthogonal to the sound insulation panel.

The third structure of the vibration-damping support structure for the soundproof wall according to the present invention.
A characteristic configuration is that, in the first characteristic configuration or the second characteristic configuration, the pair of elastic members are arranged symmetrically with respect to a vertical axis.

The fourth structure of the vibration-damping support structure for the soundproof wall according to the present invention.
The characteristic configuration is as described in claim 4,
In the characteristic configuration, the sound insulation panel is supported on the elastic support mechanism.

A fifth aspect of the vibration-isolating support structure for a soundproof wall according to the present invention.
According to a fifth aspect of the present invention, the characteristic construction is that, in the fourth characteristic construction, the sound insulation panel is supported by the elastic support mechanism at the lower end side thereof.

[Operation and Effect of Characteristic Configuration] According to the first characteristic configuration of the vibration-damping support structure for a soundproof wall according to the present invention, the soundproof wall can be easily attached to a structure while Cuts off the noise from
It is possible to reliably prevent the vibration of the structure from being emitted to the outside as noise.

That is, in the above-mentioned first characteristic structure, the sound insulation panel can shield noise from the inside of the structure, and the elastic support mechanism is attached to the upward surface of the structure.
A base portion provided with a mounting surface to be attached, and the sound insulation panel
The support surface that supports the downward surface of the support member attached to
And a pair of elastic members integrally provided,
A pair of elastic material holding slopes are provided on the base body in opposite directions.
The support portion is provided symmetrically so as to be inclined.
And parallel to each of the elastic material holding slopes.
A pair of elastic support slopes facing each other are provided symmetrically
The elastic material holding slopes and the front
The mounting surface is interposed between each of the elastic support slopes.
Attached to the upward surface of the construct and at the support surface
While supporting the downward surface of the support member, the pair of
Each of the elastic members is placed on the vertical axis under the load of the sound insulation panel.
Elastic support provided so as to be compressed and deformed in a symmetrical and diagonal direction.
Since it is composed of a holding tool and the load of the sound insulation panel is received by the pair of elastic members , the mounting structure is simple and the retrofitting work of the sound insulation panel is easy. Moreover, the elastic support mechanism provided so that each of the pair of elastic members compressively deforms in the diagonal direction symmetrical with respect to the vertical axis under the load of the sound insulation panel has small anisotropy and large vibration damping. It is possible to prevent the vibration of the structure from being transmitted to the sound insulation panel.

Therefore, it is possible to suppress the noise emission from the sound insulation panel itself by vibrating the sound insulation panel. Particularly, according to the elastic support mechanism provided so that each of the pair of elastic members is compressed and deformed by the load of the sound insulation panel in an oblique direction symmetrical with respect to the vertical axis, at least the pair of elastic members are arranged in parallel. With respect to the displacement of, since the restoration characteristic of the support state is large and the holding mechanism for preventing the lateral displacement that was conventionally required is not required, the node of the vibration transmission between the structure and the soundproof wall is Since the vibration can be limited to this elastic support mechanism and the vibration transmitted by this elastic support mechanism is damped, the soundproof wall can be made to function extremely effectively.

According to the second characteristic structure of the vibration-damping support structure for the soundproof wall according to the present invention, the function and effect of the first characteristic structure can be further enhanced. That is, although the elastic support mechanism has a small anisotropy of vibration damping, the elastic support mechanism has a particularly high vibration absorbing ability with respect to the vibration of the pair of elastic materials in the juxtaposed direction, and the pair of elastic materials are arranged in the vertical direction in the sound insulation panel. Since the sound insulation panels are arranged side by side in the direction orthogonal to, it is possible to reliably suppress the vibration of the sound insulation panel in the normal direction of the outer surface thereof, and it is possible to reliably prevent the noise emission from the sound insulation panel. is there.

According to the third characteristic constitution of the vibration-damping support structure for the soundproof wall according to the present invention, the operational effect of the first characteristic constitution or the second characteristic constitution is further ensured. That is, since the pair of elastic members are arranged symmetrically with respect to the vertical axis, the anisotropy of the vibration characteristics can be made particularly small, and the vibration absorbing ability can be further increased. Further, since the supporting load for supporting the soundproof wall acts uniformly on the elastic member of the elastic supporting mechanism, it is possible to enhance the vibration damping performance of the elastic supporting member,
It is also possible to reduce the size of the elastic support mechanism.

According to the fourth characteristic constitution of the vibration-proof support structure for a soundproof wall according to the present invention, the support structure for the soundproof wall can be simplified while achieving the operational effects of the first to third characteristic structures.
In other words, since the elastic support mechanism can be used as the lower support mechanism and the soundproof wall is supported by the elastic material itself in the elastic support mechanism, the vibration system formed by the elastic support mechanism can be simplified as a simple series damping vibration system. Therefore, it is structurally stable and can be easily retrofitted with a soundproof wall.

According to the fifth characteristic constitution of the vibration-damping support structure for the soundproof wall according to the present invention, the noise radiation caused by the vibration of the sound insulation panel itself can be achieved, among the effects of the fourth characteristic constitution. The effect of preventing can be enhanced. That is, since the sound insulation panel can be supported only by holding it on the upper end side, it is possible to reduce the number of vibration transmission nodes from the structure. Moreover, since the sound insulation panel arranged on the lower side can be held by the sound insulation panel arranged adjacently on the upper side, it becomes easy to arrange the sound insulation panels in the vertical direction, and the sound insulation wall can be easily formed. Become.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION An example of an embodiment of a vibration-proof support structure for a soundproof wall according to the present invention will be described below with reference to the drawings. FIG. 1 is a side sectional view of a factory outer wall portion showing an example of a structure in which a soundproof wall is attached by a vibration isolation support structure according to the present invention, and FIG. 2 is a side sectional view of a main part of a building showing an example of an elastic support mechanism thereof. FIG. 3 is a front view of a main part of the building in the mounting part of the soundproof wall, FIG. 4 is a side view showing an example of the elastic support mechanism, and FIG. 5 is a side view of the main part showing the elastic support structure of the soundproof wall. 6 is an exploded perspective view showing the elastic support structure, and FIG. 7 is an operation explanatory view showing an operation model of the elastic support mechanism. It should be noted that the same elements as those in FIG. 11 used in the above-mentioned conventional technique or elements having the same function are designated by the same or related numerals as those in FIG. Omitted part of.

A vibration-proof support structure for a soundproof wall according to the present invention will be described below with reference to FIG. 1 by using an example in which a soundproof wall is attached to the outside of an existing outer wall of an existing factory building. The structure 8 contains a source of noise and vibration inside. Construct 8 used as the factory shown
Is an existing steel frame structure, and the outer wall portion is formed by a slate wall 28. Equipment such as a roots blower and an air compressor, which are sources of the noise and vibration, are installed on the floor by interposing vibration damping rubber as a vibration damping material 12 on the third floor of the building 8. Therefore, the vibration of the device is transmitted to the floor of the third floor, and the body of the structure 8 itself vibrates. Therefore, the soundproof wall 1 is newly installed outside the slate wall 28.

The soundproof wall 1 is provided with an elastic support mechanism 3 according to the present invention on a bracket 9 fixed to the structure 8.
The sound insulation panels 2 supported by the elastic support mechanism 3 are formed in series. As the elastic support mechanism 3, for example, FIG.
As shown in FIG. 2, a pair of elastic members 4 made of rubber is interposed between the lower base portion 6 and the upper support portion 5 arranged above. In the illustrated example, a pair of the elastic support mechanisms 3 are arranged side by side in the width direction of the sound insulation panel 2, and fixed on the bracket 9 with a mounting bolt 7, so that the sound insulation panel 2 is attached to each elastic support mechanism 3. It is fixed to the mounting bolt 7 with.

As shown in FIG. 3, the elastic support mechanism 3 is formed symmetrically, and the elastic member 4 is mounted on a pair of elastic member holding slopes 6a formed on the base member 6. The base portion 6, the elastic member 4, and the support portion 5 are integrally formed by being sandwiched between a pair of elastic support slopes 5a formed on the support portion 5 (FIG. Four
reference). The elastic material holding slope 6a is formed as a slope inclined toward the axis of symmetry of the elastic support mechanism 3, and the elastic support slope 5a is formed as a slope inclined away from the axis of symmetry. The elastic material holding slope 6a and the elastic support slope 5a are formed parallel to each other in a state where the elastic material 4 is sandwiched and fixed between the elastic material holding slope 6a and the elastic support slope 5a. (See Figure 3).

The elastic member holding slope 6a of the base portion 6
Is formed on a flat mounting surface 6b whose normal line is the axis of symmetry.
Similarly, the opposite side is also formed with a flat support surface 5b whose normal line is the axis of symmetry. In the illustrated example, the elastic member holding slope 6a has an inter-face angle of 100 °, and the elastic support slope 5a has an inter-face angle of 260 °.
With this configuration, in the elastic support mechanism 3, when the support surface 5b receives the load in the symmetrical axis direction, the elastic support mechanism 3 is most stable in the symmetrical state and is displaced laterally. In this case, it has a restoring characteristic of returning to the symmetrical state. Therefore, if the base portion 6 is attached to a bracket and the sound insulating panel 2 is supported by the support portion 5, the sound insulating panel 2 can be supported very stably.

As shown in FIG. 7 (a), the mechanical model of the elastic support mechanism 3 exemplified above is different from the load acting axis Z, which is in the same direction as the axis of symmetry, in different directions. It can be expressed by a pair of damping vibration systems X, X having the elastic support axis Ze inclined with respect to the axis Z as the axis of action Z1 of the biaxial force. Although detailed description is omitted, the pair of damping vibration systems X, X can be expressed by being replaced by an equivalent model as shown in FIG. That is, the pair of damping vibration systems X, X
Instead of, the vertical damping vibration system Y1 having the load acting axis Z as the vertical force acting axis Z2 and the horizontal force acting axis Z3 orthogonal to the load acting axis Z in the horizontal direction It can be expressed as a synthetic vibration system with the damping vibration system Y2.

Here, the pair of elastic support shafts Ze, Ze
Depending on the setting condition of the angle between (see (a) in the figure), the spring constant of the vertical damping vibration system Y1 is relatively large, and the viscous resistance to its displacement is relatively low.
The spring constant of the horizontal damping vibration system Y2 is relatively small, and the viscous resistance to its displacement can be relatively high. Therefore, the soundproof wall 1 can effectively damp the vibration transmitted in the normal direction of the surface without elastically supporting it from the side while supporting it with a sufficient supporting force. This vibration damping capability is obtained by the pair of elastic support shafts Ze, Z.
If the surface including both e is orthogonal to the surface of the soundproof wall 1, the height can be increased most effectively.

In the example of the factory shown in FIG. 1, as shown in FIG. 4, the bracket 9 is planted on the upper surface of the bracket 9 on the mounting surface 6b of the base portion 6 which is a constituent member of the elastic support mechanism 3. The support member 13 attached to the body flange 15 for attaching the sound insulation panel 2 is attached to the support surface 5b of the support portion 5 which is also a component of the elastic support mechanism 3 It is fixed to the supporting portion 5 by using a mounting bolt 7 which is provided. In order to ensure safety, as shown in FIG. 5, the fastening member 11 is used as the fall prevention member 17 made of C-shaped steel standing upright on the upper surface of the bracket 9 inside the elastic support mechanism 3. The support member 13 is elastically supported by interposing a cushioning plate member 18 made of vibration-proof rubber. On the support member 13 side of the fastening member 11, between the support member 13 and a buffer spacer 19 made of a vibration-proof rubber having a bush portion that can be internally fitted in a bolt insertion hole of the buffer plate member 18. Interposed with washers.

The support member 13 is, as shown in FIG.
Steel plates are welded to both ends of the H-shaped steel, and the other end is attached to the fall prevention member 17 (the drawing is a perspective view as seen from the side of the trunk 15). The support member 13 is attached to the frame 14 made of H-shaped steel by welding,
A body collar 15 for attaching the sound insulation panel 2 is attached to the position 4. A square steel tube is used for the body edge 15. The sound insulation panel 2 is fixed by driving a pin 16 into the body edge 15. Then, the adjacent ends of the sound insulation panel 2 are connected to each other by engaging with each other (FIG. 2).
reference).

[Other Embodiments] Some examples of embodiments different from the embodiments described above will be described below.

<1> In the above embodiment, an example was described in which a soundproof wall was attached to the outside of the existing outer wall of the factory building, but the present invention is not applied only to the factory building, but to the inside of the factory building. Any structure can be effectively used as long as it has a source of noise and vibration, and the type of the structure is not limited. In addition, the sources of noise and vibration contained inside are not limited to fixed sources, but include those that are movable, those that move, those that are carried into the structure within a short period of time, or those that travel into the structure. . Therefore, the structure and the source of noise and vibration include, for example, a structure such as a multi-storey parking lot or a warehouse where a vehicle enters and the vehicle becomes a source of noise and vibration. Is included in the sources of noise and vibration. That is, the vehicle causes vibration on the floor surface when traveling in the field, and the vehicle itself generates noise. In the case of a warehouse, a lifting machine or the like generates noise and vibration when the storage material is lifted, and the lifted storage material causes vibration on the floor of the warehouse.

<2> In the above-described embodiment, the structure 8 is an existing steel structure, and the outer wall portion is formed of the slate wall 28. However, for example, a soundproof wall is used. Even if you have already installed
In the case of the multi-storey parking lot illustrated in the above <1>, even if the engine noise of the vehicle is blocked by the soundproof wall, vibration occurs in the skeleton as the vehicle travels in the hall, and the vibration causes the vibration to occur. The existing soundproof wall may vibrate, and the soundproof wall itself may be a secondary noise source, and the present invention is also effective for such a structure. For example, the secondary noise generation can be sufficiently prevented by replacing only the existing soundproof wall support structure with the elastic support structure according to the present invention.

<3> In the above embodiment, an example in which the elastic support shaft Ze of the elastic support mechanism 3 is composed of only two shafts has been described, but another elastic support shaft may be added. For example, the elastic support slopes 5a may be formed of pyramidal surfaces, and the elastic material holding slopes 6a corresponding to the respective surfaces may be provided. The pyramid can be arbitrarily selected such as a triangular pyramid (the elastic supporting shaft has three axes), a quadrangular pyramid (the elastic supporting shaft has four axes), and the like.

<4> In the above embodiment, as an example of the elastic support mechanism 3, the elastic member 4 is interposed between the elastic member holding slope 6a of the base 6 and the elastic support slope 5a of the support 5. However, the elastic support mechanism 3 does not necessarily have to be integrally formed, and the elastic member 4 is a coil spring, a leaf spring, or the like. May be .

<5> When the spring or the like exemplified in the above <4> is used, the base portion 6 is arranged in the elastic supporting direction.
It is further preferable that a cushioning member 20 that provides viscous resistance to relative displacement between the above and the supporting portion 5 is interposed. As the cushioning member 20, for example, a cushioning mechanism 21 utilizing a fluid resistance containing an orifice 24 as shown in FIG. 8 may be provided. The one shown is
An outer tubular portion 22 attached to the base portion 6 and an inner tubular portion 2 attached to the support portion 5 and airtightly fitted to the outer tubular portion 22 slidably in the elastic support axis Ze direction.
3, the inner cylinder portion 23 is provided with a small opening at the tip portion inserted into the outer cylinder portion 22 to form an orifice 24, and the outer cylinder portion 22 is buffered to a depth at which the tip portion is immersed. A fluid resistance type buffer mechanism 21 filled with a fluid 25.

<6> In the above-described embodiment, the elastic support mechanism 3 is constituted by arranging the support portion 5 above the base portion 6 so that the elastic support shaft Ze is spaced apart downward. Although the example in which the elastic member 4 is sandwiched between the base portion 6 and the support portion 5 has been described, the support portion 5 is positioned below the base portion 6 to elastically support the support portion 5. The elastic support mechanism 3 so as to be suspended from the base portion 6
May be configured. For example, as shown in FIG.
The elastic material holding slope 6a is formed on the upper surface of the base portion 6, the elastic material 4 is attached to the elastic material holding slope 6a, and the through hole 26 substantially orthogonal to the elastic material holding slope 6a is formed on the elastic material 4 and the elastic material 4 described above. The base portion 6 and the base portion 6 are formed.
It is also possible to form a through hole 26 into which the hanging support rod 27 inserted through the through hole 26 penetrating to the inside can be fitted in the supporting portion 5 and elastically support the supporting portion 5 on the base portion 6. .

<7> In the example shown in FIG. 9, a pair of elastic support shafts Ze, Ze formed of two axes are arranged so as to be gradually separated from the base portion 6 side to the support portion 5 side. However, in the case of such suspension support, as shown in, for example, FIG. 10, the pair of elastic support shafts Ze, Ze.
In the case of the above, it is more excellent in restoring property if they are arranged so as to be separated on the side of the base portion 6 and close to each other on the side of the supporting portion 5.

[0036]

[Brief description of drawings]

FIG. 1 is a side sectional view showing an example of a factory to which a vibration-proof support structure for a soundproof wall according to the present invention is applied.

FIG. 2 is a side sectional view of a main part of a building showing an example of the vibration-proof support structure according to the present invention.

FIG. 3 is a cross-sectional front view of the main part of the vibration-proof support structure shown in FIG.

FIG. 4 is a partial cross-sectional view of the elastic support structure shown in FIG.

5 is an enlarged view of a main part of FIG.

FIG. 6 is an exploded perspective view of a main part of FIG.

FIG. 7 is an operation explanatory view relating to an example of an elastic support structure according to the present invention.

FIG. 8 is a side view of a main part showing another example of the vibration-proof support structure according to the present invention.

FIG. 9 is a conceptual diagram of another example of the vibration-proof support structure according to the present invention.

FIG. 10 is a conceptual diagram of another example of the anti-vibration support structure according to the present invention.

FIG. 11 is a vertical cross-sectional view of a main part of a structure showing a conventional vibration isolation support structure for a soundproof wall.

[Explanation of symbols]

2 sound insulation panel 3 elastic support mechanism 4 elastic material 5 support portion 5a elastic support slope 5b support surface 6 base portion 6a elastic material holding slope 6b mounting surface 8 structure 13 support member

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Akio Miyakawa               770-5 Yodabashi, Fuji City, Shizuoka Prefecture Limited Company               Yukiakinai                (56) References JP-A-9-96124 (JP, A)                 52-169908 (JP, U)                 Actual Kaihei 1-98801 (JP, U)                 Actual Kaihei 1-98936 (JP, U)

Claims (5)

(57) [Claims] 1. A structure for accommodating a noise and vibration source inside, wherein the structure is a vibration-proof support structure for a soundproof wall for preventing noise from the structure to the outside, the soundproof wall forming the structure and the soundproof wall. An elastic support mechanism is provided between the panel and the panel to allow relative vibration of the sound insulation panel and to receive the load of the sound insulation panel with a pair of elastic materials so as to damp the relative vibration. The structure is supported by an elastic support mechanism, and the elastic support mechanism is provided with a mounting surface to be attached to the upward surface of the structure.
Base member and supporting member attached to the sound insulation panel
A supporting portion provided with a supporting surface for supporting the downward surface of the
The pair of elastic members are integrally provided, and the pair of elastic members are
Left and right pair so that the elastic material holding slopes are inclined in opposite directions.
And a pair of elastic members on the supporting portion.
Left pair of elastic support slopes parallel to each of the retention slopes
Provided symmetrically to the right, the elastic members were made to face each other in parallel.
In each of the elastic material holding slope and the elastic support slope
Attach the mounting surface to the upward surface of the building
And support the downward surface of the support member on the support surface.
In this state, each of the pair of elastic members is formed of an elastic support member that is compressed and deformed by a load of the sound insulation panel in a diagonal direction symmetrical with respect to the vertical axis. Support structure. 2. The vibration isolation support structure for a soundproof wall according to claim 1, wherein the pair of elastic members are arranged side by side in the vertical direction in a direction orthogonal to the sound insulation panel. 3. The vibration isolation support structure for a soundproof wall according to claim 1, wherein the pair of elastic members are arranged symmetrically with respect to a vertical axis. 4. The vibration isolation support structure for a sound insulation wall according to claim 1, wherein the sound insulation panel is supported on the elastic support mechanism. 5. The vibration isolation support structure for a sound insulation wall according to claim 4, wherein the sound insulation panel is supported by the elastic support mechanism at a lower end side thereof.