JP3020812B2 - Sound and heat insulation structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a three-dimensional sound and heat insulating plate,
In particular, the present invention relates to a soundproof and heat insulating structure provided with a soundproof and heat insulating plate for an exhaust manifold of an automobile.

[0002]

2. Description of the Related Art In an engine room of an automobile, various electronic devices for performing engine control, running control and the like are arranged in addition to the engine. Since these electronic devices are exposed to high heat from a heat source engine, the heat sources are provided with a heat shield to protect these electronic devices. That is, the heat to the electronic device is shielded by disposing the heat shield plate at a predetermined distance around the exhaust manifold of the engine. Further, since the exhaust manifold is generally a noise generating source, it is required that the heat shield plate is a soundproof heat shield plate which also performs a soundproof function.

[0003] However, as a conventional soundproof heat insulating plate, a metal plate or a metal plate or a plurality of metal plates laminated and fixed or an asbestos sheet or the like sandwiched between them is known. In particular, it does not sufficiently fulfill the soundproofing function. That is, in such a conventional soundproof and heat insulating plate,
Noise may increase due to solid-borne noise from the exhaust manifold. In addition, the space between the exhaust manifold and the sound insulating and heat insulating plate serves as a resonance box, and the noise from the exhaust manifold repeatedly reflects in the space, thereby amplifying the noise and increasing the noise value of the sound insulating and heat insulating plate. Rises.
Furthermore, even when an asbestos sheet or the like is interposed between a plurality of metal plates as a sound absorbing material, a sufficient sound absorbing effect is not obtained because the metal plate on the outer surface reflects noise.

Further, an exhaust manifold cover for covering the exhaust manifold is disclosed in Japanese Utility Model Laid-Open No. 1-158513. The cover is composed of an inner plate on the exhaust manifold side, an outer plate outside the inner plate, and a sound absorbing material interposed between the inner plate and the outer plate, and a plurality of openings in the inner plate. Is formed. In the manifold cover having such a configuration, the radiation sound of the exhaust manifold is absorbed by the sound absorbing material through the opening of the inner plate. However, the reflection of the radiation sound is repeated at portions other than the opening of the inner plate, and the radiation sound is amplified. This is not considered at all. As a result, the noise prevention effect is low,
Particularly, the effect of preventing high-frequency noise is extremely low.

[0005]

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned problems of the prior art and to provide a soundproof heat insulating and heat insulating plate for a three-dimensional exhaust manifold which is excellent in soundproofing, heat shielding and durability. It is to provide a heat shielding structure.

[0006]

According to the present invention, there is provided an exhaust manifold and a soundproof heat insulating plate, wherein an air layer is provided between the soundproof heat insulating plate and the exhaust manifold.
In the sound-insulating and heat-insulating structure, the sound-insulating and heat-insulating plate is disposed on a surface of the metal substrate formed in a predetermined three-dimensional shape, a nonwoven fabric provided on the surface of the metal substrate on the exhaust manifold side, and And a woven wire mesh fixed to the metal substrate, wherein the woven wire mesh makes the nonwoven fabric adhere to the metal substrate, and the woven wire mesh is a metal wire having a wire diameter of 0.1 to 1 mm. Consisting of a mesh of 5 to 100 mesh.

As a metal substrate, a steel plate having a thickness of 0.5 to 2 mm,
A plated steel plate or a stainless steel plate can be used. If the thickness of the metal substrate is less than 0.5 mm, amplified noise or cracks are likely to occur due to engine vibration, while 2
If it exceeds mm, the overall weight becomes significantly heavy, and it is difficult to reduce the weight.

[0008] The nonwoven fabric is made of inorganic fibers. Ceramic fibers, glass wool, silica fibers or rock wool can be used as the inorganic fibers.

As the ceramic fiber, it is preferable to use an alumina ceramic fiber or a silica alumina ceramic fiber, which is the most common nonwoven fabric which can satisfy the conditions such as the density shown below.
The cost is low and the safety is high. When a ceramic fiber is used, it is preferable that the average fiber diameter is 1.5 to 20 μm and the average fiber length is 5 mm or more. Further, the ceramic fiber has excellent heat resistance and durability. When the requirement for heat resistance is not so important, glass wool is preferred in terms of cost.

[0010] Next, the nonwoven fabric is 0.05 to 0.5 g / cm ³ at the time of assembly.
, An average thickness of 0.5 to 15 mm and an average compressibility of 1% or more. The average compression ratio is a ratio of the volume of the nonwoven fabric reduced by the compression.
If it is less than the average bulk density 0.05 g / cm ^3, present a problem in durability, greater than 0.5 g / cm ^3, which may cause a sound absorption failure problems. Further, if the average thickness is less than 0.5 mm, the sound absorption and heat insulation are insufficient, and if the average thickness is more than 15 mm, it may not be able to be mounted on the engine in a limited engine room. Furthermore, by assembling with an average compression ratio of 1% or more, the nonwoven fabric can be fixed effectively, and the position of the nonwoven fabric can be effectively prevented from being displaced or powdered due to engine vibration or the like. .

In the present invention, the non-woven fabric made of inorganic fibers absorbs noise as follows. That is, the energy of the sound that has entered the gap between the fibers of the inorganic fibers is converted into heat energy by viscous resistance of the capillary tube, or is converted into the heat energy by vibrating with the energy of the sound that the fiber itself has entered. In this way, the inorganic fibers serve as a sound absorbing material.

On the other hand, the nonwoven fabric also absorbs vibration as follows. That is, the vibration energy transmitted from the engine to the exhaust heat-insulating heat-insulating plate is converted into heat energy by internal friction of the inorganic fibers. In this way, the nonwoven fabric also plays the role of a damping material.

[0013] Since the woven metal mesh of the metal wire is located closest to the exhaust manifold side of the engine, it is necessary to have excellent heat resistance and flexibility. Flexibility is required not only to tightly fix the nonwoven fabric to the curved surface of the three-dimensional metal substrate, but also to effectively absorb the nonwoven fabric without reflecting the sound emitted from the exhaust manifold compared to a metal plate This is because the vibration transmitted to the metal substrate can be effectively attenuated. From the viewpoint of heat resistance and flexibility, the metal wire constituting the woven wire mesh is preferably made of stainless steel (SUS 304), brass or galvanized steel.

Further, the woven wire mesh has a wire diameter of 0.1 to 1.0 mm,
The mesh is 5 to 100 mesh. When the wire diameter is less than 0.1 mm, the flexibility is excellent, but the durability is insufficient.
If it exceeds 1.0 mm, the durability is excellent, but the flexibility is inferior and the workability deteriorates. In particular, a wire diameter of 0.2 to 0.3 mm is preferable. Also, if the mesh is coarser than 5 mesh, the nonwoven fabric will fall off the mesh due to the vibration of the automobile or traveling wind, etc., and if it is finer than 100 mesh, the sound radiated from the exhaust manifold will be reflected and the soundproofing effect will be reduced. I do. The mesh is preferably 40 to 50 mesh.

In the soundproof and heat insulating plate according to the present invention, the outermost peripheral edge of the metal substrate is subjected to clinching, whereby the edge is bent in the direction of the nonwoven fabric and the woven wire mesh, and the periphery of the nonwoven fabric and the woven wire mesh is formed. The coating can be fixed. By this clinch processing, the woven wire mesh and the nonwoven fabric do not protrude in the side direction, and the ends of the metal substrate and the woven wire mesh do not appear on the side surface. Therefore, even when the hand touches the end during the work of attaching the soundproof heat insulating plate, there is no risk of injury or the like, and the device is safe.

The fixing between the woven wire mesh and the metal substrate is performed by spot welding or stud welding, riveting or crimping. From the viewpoint of productivity, riveting or spot welding is preferable. In this case, the woven wire mesh can be completely fixed to the curved surface of the metal substrate. Also, from the viewpoint of durability, it is preferable to use a stopper.

When fixing the woven wire mesh to the metal substrate, 10 to 10
It is particularly preferable to fix at a pitch of 100 mm. If the pitch interval is less than 10 mm, the fixed portion becomes a sound bridge, and the soundproofing effect may be reduced. On the other hand, when the pitch interval is 100 mm or more, the state of close contact of the nonwoven fabric is incomplete, and the position of the nonwoven fabric tends to shift or become powdered due to engine vibration or the like.

In the case of spot welding, the nugget diameter is 2 to 5
It is preferably mm. If the nugget diameter is less than 2 mm, the strength of the weld bond between the woven wire mesh and the metal substrate will be weak, resulting in poor durability. If it is larger than 5 mm, a problem of a sound bridge occurs. In this case, it is preferable to provide a welding hole in advance in a portion of the nonwoven fabric corresponding to a position to be spot-welded. This hole preferably has a diameter of 7 to 15 mm. When the diameter is smaller than 7 mm, it becomes difficult to insert an electrode for spot welding, and when the diameter is larger than 15 mm, the sound absorbing effect is reduced.

When the stopper is used, it is preferable that the stopper has a hole diameter of 10 mm or less. If the diameter of the hole of the eyelet is larger than 10 mm, the sound will pass through that part and the soundproofing effect will be reduced.

In the case of stud welding, an ordinary stud pin such as L, T or U-shape can be used. Also,
The diameter of the stud pin is preferably 0.5 to 3.0 mm. Diameter
If it is less than 0.5 mm, the strength of the stud pin itself becomes insufficient, while if it exceeds 3.0 mm, a sound bridge may be generated.

The nonwoven fabric is usually produced in the form of a sheet of short fiber nonwoven fabric, and is punched into a predetermined shape.
On the other hand, the woven wire mesh is used for adhering the nonwoven fabric to the metal substrate to absorb the vibration of the metal substrate. Therefore, if there is a gap between the woven wire mesh and the nonwoven fabric, the state of adhesion between the metal substrate and the nonwoven fabric becomes incomplete, and the nonwoven fabric vibrates due to vibration during the engine or running, causing displacement, powdering and scattering. As a result, the durability is significantly deteriorated. For this reason, it is preferable that the nonwoven fabric is formed integrally with the woven wire mesh, and this is fixed to the metal substrate with an adhesive. As the adhesive, an inorganic binder is suitable from the viewpoint of heat resistance.

The nonwoven fabric and the woven wire mesh can be integrally formed by disposing the woven wire mesh in a papermaking mold used for the wet papermaking method of the nonwoven fabric so as to be detachable and wet papermaking.

Further, when securing the woven wire mesh to the metal substrate by spot welding or the like, in order to secure the space occupied by the nonwoven fabric, when viewed from the side facing the exhaust manifold,
The fixed part of the metal substrate can be machined convexly, or the fixed part of the woven wire mesh can be machined concavely, or both. In addition, a commercially available nonwoven fabric of inorganic fibers generally has low extensibility, and when it is forcibly stretched, cracks and breakage are likely to occur. For this reason, when using a commercially available nonwoven fabric, it is advantageous to form it in a wet state. That is, since the nonwoven fabric is in a wet state,
The extensibility is improved, so that cracks, breakage, and the like do not occur even when the metal substrate and the woven wire mesh follow irregularities or curved surfaces.

Short fiber non-woven fabrics such as glass wool, rock wool, and silica-alumina ceramic fibers used as non-woven fabrics may be used under the conditions such as running wind and muddy water in addition to vibrations during engine or running of an automobile. Its edges scatter or flow out gradually. That is,
A part of the outer peripheral portion, the opening portion, or the curved surface portion of the nonwoven fabric sandwiched between the metal substrate and the woven metal mesh has a structure not fixed to the metal substrate or the woven metal mesh, and the nonwoven fabric is easily scattered or flows out. For this reason, 3 to 15 from the outer edge of the nonwoven fabric
Curing treatment can be performed on the width part of mm using an inorganic binder. Examples of the inorganic binder include an aqueous solution of a clay mineral such as colloidal silica, colloidal alumina, or montmorillonite, for example, silica sol “Snowtex (trade name, manufactured by Nissan Chemical Industries, Ltd.)”. When the width of the curing treatment is smaller than 3 mm, the curing treatment part is easily peeled off from the interface between the cured treatment part and the uncured treatment part. On the other hand, when the curing treatment is performed, the sound absorption of the nonwoven fabric itself deteriorates. Therefore, the width of the curing treatment is preferably as narrow as possible, that is, 15 mm or less, and more preferably about 8 to 10 mm.

The sound-insulating and heat-insulating plate manufactured in this manner has the surface of the woven wire mesh arranged on the exhaust manifold side, and is provided with an interval of 5 to 50 mm between the woven wire mesh and the exhaust manifold. If the interval is less than 5 mm, the heat shielding and soundproofing effects are insufficient, and if the interval is more than 50 mm, it may not be possible to mount it in a limited space of an engine room, for example.
Further, it is preferable that the soundproof heat insulating plate and the exhaust manifold are not in contact with each other.

[0026]

According to the present invention, a sound insulating and heat insulating plate according to the present invention comprises a metal substrate formed into a predetermined shape, a nonwoven fabric provided on the surface of the metal substrate, and a nonwoven fabric disposed on the surface of the nonwoven fabric and fixed to the metal substrate. Woven metal mesh of metal wire having a wire diameter of 0.1 to 1 mm and a mesh of 5 to 100 mesh. In particular, the non-woven fabric is integrated with the woven wire mesh, or the non-woven fabric is attached to the surface of the metal substrate in a wet state, and the woven wire mesh is disposed on the surface of the non-woven fabric to form the soundproof heat insulating plate. Since the non-woven fabric and the woven metal mesh are arranged so as to face the exhaust manifold of the engine, noise from the engine and the like is absorbed by the non-woven fabric and does not propagate to the metal substrate. Therefore, noise is not transmitted outside through the metal substrate.

Since the woven wire mesh is arranged on the sound source side for holding the nonwoven fabric, the sound of the sound source side is passed through the nonwoven fabric through the mesh of the woven wire mesh, so that the sound absorbing effect of the nonwoven fabric is extremely effectively exhibited. In addition, the woven wire mesh has an excellent vibration damping effect.
Further, the nonwoven fabric has an excellent heat shielding effect, and can easily block heat generated from an engine or the like, particularly high heat from an exhaust manifold. Further, in the soundproof and heat insulating plate according to the present invention, as described above, the nonwoven fabric is supported by the woven wire mesh, so that the nonwoven fabric is prevented from being displaced, powdered, scattered, or spilled out, thereby increasing the durability. Since the woven wire mesh closely supports the nonwoven fabric together with the metal substrate, wear of the nonwoven fabric is also prevented. Further, since the woven wire mesh is fixed to the metal substrate by spot welding or the like, the attachment of the woven wire mesh and the nonwoven fabric to the metal substrate is ensured, and a complicated three-dimensional soundproof and heat insulating plate can be easily manufactured. Advantageous Effects of Invention According to the present invention, even when continuously used at high temperatures, there is no reduction in vibration damping properties, and a soundproof heat shield provided with a soundproof heat shield plate for an exhaust manifold having a three-dimensional shape excellent in soundproof, heat shield and durability. Structure can be provided.

The sound insulating and heat insulating plate for an exhaust manifold according to the present invention can be applied to high heat and noise generating devices such as an engine cover, a muffler, a turbocharger cover and a catalytic converter, and exhibits excellent effects as a sound insulating and heat insulating material. can do.

[0029]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. Embodiment 1 The soundproof and heat insulating plate of this example is used as a soundproof and heat insulating plate in an exhaust manifold of an automobile, and has a three-dimensional shape corresponding to the manifold. As shown in FIGS. 1 to 3, the soundproof and heat insulating plate 1 includes a three-dimensionally shaped metal substrate 2, a nonwoven fabric 3 provided on a surface of the metal substrate 2 on the side of an exhaust manifold (not shown), A woven metal mesh 4 of a metal wire arranged on the surface of the nonwoven fabric 3 and fixed to the metal substrate 2 by spot welding, the outermost portion of which is subjected to clinching (2a) as shown in FIG. I have.

As shown in Table 1, as the metal substrate 2,
Using a 1mm thick aluminum-plated steel plate (SACD80), the non-woven fabric 3 and the woven wire mesh 4 have a mesh of 50 mesh and a wire diameter of 0.
Average fiber diameter on 18mm stainless steel (SUS304) plain woven wire mesh
A silica-alumina ceramic fiber with an average fiber length of 2.2 μm and an average fiber length of 30 mm is integrally formed by wet papermaking. The average thickness of the nonwoven fabric formed by wet papermaking when attached to the metal substrate 2 is 4 mm, and the average bulk density is 0.25 g /
cm ³ , the average compression ratio is about 5%.

In order to fix the woven wire net 4 to the metal substrate 2 by spot welding, a spot welding hole 5 having a diameter of about 10 mm is provided in the nonwoven fabric 3 at a position corresponding to a fixed pitch interval of 30 to 80 mm spot welding. ing. The nugget diameter at the spot welded portion 6 between the woven wire mesh 4 and the metal substrate 2 is 3 mm.

The thus prepared soundproof and heat insulating plate 1 is
Attached around the exhaust manifold of a liter, four-cylinder diesel engine at intervals of 5 to 30 mm, the engine was operated at 4,000 revolutions per minute, and the noise of the engine was measured during the operation. The results are shown in Table 2. The values shown in Table 2 are the average values of the noise values measured at positions 1 m away from the engine on the right, left, front, and above, respectively.

Next, a length of 220 mm from the sound and heat insulating plate 1 was set.
A strip-shaped test piece having a width of 10 mm was prepared, and the loss coefficient at each frequency was measured using the test piece in accordance with the vibration damping characteristic test method of the damping steel sheet specified in JIS-G-0602. Table 3 shows the results. In addition, a disk-shaped test piece was prepared from the sound-insulating and heat-insulating plate 1, and the sound absorption coefficient at each frequency was measured using the test piece according to the normal incidence sound absorption rate measurement method by the in-pipe method specified in JIS-A-1405. Table 4 shows the results.

Example 2-9 As shown in Table 1, the thickness of the metal substrate 2, the average bulk density and average thickness of the nonwoven fabric 3, It was prepared by changing the type, mesh and wire diameter, and the loss coefficient and sound absorption at each frequency were measured by the method described in Example 1. The results are shown in Tables 3 and 4.

Example 10 As shown in FIGS. 4 and 5, a non-woven fabric 7 having a mean thickness of 5 mm and a silica-alumina ceramic fiber having a mean fiber diameter of 2.2 μm and a mean fiber length of 30 mm, which was formed into a sheet, was meshed in advance. Is fixed to the metal substrate 2 described in Example 1 by stud welding together with a plain woven wire mesh 8 made of stainless steel (SUS304) having a mesh size of 10 mm and a wire diameter of 0.8 mm to produce a soundproof and heat insulating plate. In this case, a stud pin having a diameter of 2 mm is vertically welded to the metal substrate 2 at a fixed pitch of 50 mm, a nonwoven fabric 7 and a woven wire mesh 8 are inserted into the stud pin, and then the stud is adjusted so that the average compressibility of the nonwoven fabric is about 5%. Bend the tip of the pin. The noise- and heat-insulating plate thus manufactured was attached around the exhaust manifold of a 2-liter, 4-cylinder diesel engine, and the noise of the engine was measured in the same manner as in Example 1. The results are shown in Table 2. Further, the loss coefficient and the sound absorption coefficient at each frequency were measured by the method described in Example 1, and the results are shown in Tables 3 and 4.

Example 11 The same method as that described in Example 10 except that a stainless steel plate (SUS304) was used as the metal substrate and a glass wool mat obtained by needle-punching glass fibers manufactured by Nakagawa Sangyo was used as the nonwoven fabric. To produce a sound and heat insulating plate. The thus prepared soundproof and heat insulating plate was attached around the exhaust manifold of a 2-liter, 4-cylinder diesel engine, and the engine noise was measured in the same manner as in Example 1.
Table 2 shows the results. Further, the loss coefficient and the sound absorption coefficient at each frequency were measured by the method described in Example 1, and the results are shown in Tables 3 and 4. The average thickness when the nonwoven fabric is attached is 12 mm, the average bulk density is 0.08 g / cm ³ , and the average compressibility is about 5%.

Example 12 A woven wire mesh was formed on a metal substrate using a stainless steel (SUS304)
A sound-insulating heat-insulating plate is produced in the same manner as described in Example 1, except that it is fixed using a hole diameter of 5 mm). The noise- and heat-insulating plate thus manufactured was attached around the exhaust manifold of a 2-liter, 4-cylinder diesel engine, and the noise of the engine was measured in the same manner as in Example 1. The results are shown in Table 2. Further, the loss coefficient and the sound absorption coefficient at each frequency were measured by the method described in Example 1, and the results are shown in Tables 3 and 4. In addition, 10 mm from the outer edge of the nonwoven fabric
Is hardened with colloidal silica having a solid content of 10%.

Comparative Example 1 The same procedure as described in Example 10 was used as the nonwoven fabric, except that punched metal (aperture diameter 6 mm, aperture ratio 30%) made of aluminized steel was used instead of the woven wire mesh. A soundproof and heat insulating plate is produced in the same manner as described above. The perforated metal is fixed to the metal substrate by spot welding at the outer periphery. The noise- and heat-insulating plate thus manufactured was attached around the exhaust manifold of a 2-liter, 4-cylinder diesel engine, and the noise of the engine was measured in the same manner as in Example 1. The results are shown in Table 2. Further, the loss coefficient and the sound absorption coefficient at each frequency were measured by the method described in Example 1, and the results are shown in Tables 3 and 4.

Comparative Example 2 Two aluminum-plated steel sheets (thickness:
0.6mm), and the outer periphery thereof is joined by spot welding to produce a soundproof and heat insulating plate. The noise- and heat-insulating plate thus manufactured was attached around the exhaust manifold of a 2-liter, 4-cylinder diesel engine, and the noise of the engine was measured in the same manner as in Example 1. The results are shown in Table 2.
Further, the loss coefficient and the sound absorption coefficient at each frequency were measured by the method described in Example 1, and the results are shown in Tables 3 and 4.

[0040]

[Table 1]

[0041]

[Table 2]

[0042]

[Table 3]

[0043]

[Table 4]

[Brief description of the drawings]

FIG. 1 is a partially cutaway plan view of an example of a soundproof and heat insulating plate according to the present invention.

FIG. 2 is a schematic partial cross-sectional view along the line II of FIG. 1;

FIG. 3 is a schematic partial sectional view taken along the line II-II of FIG.

FIG. 4 is a partially cutaway plan view of another example of the soundproof and heat insulating plate according to the present invention.

FIG. 5 is a schematic partial sectional view taken along the line VV in FIG. 4;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Sound insulation heat insulation board 2 Metal substrate 3 Nonwoven fabric 4 Metal wire woven wire mesh 5 Welding hole 6 Spot welded part 7 Nonwoven fabric 8 Metal wire woven wire mesh 9 Stud pin

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-4-308315 (JP, A) JP-A-53-98557 (JP, A) JP-A-62-38817 (JP, A) 92422 (JP, U) Shokai Sho 57-82466 (JP, U) Shokai Hei 1-158513 (JP, U) Shokai Hei 4-71733 (JP, U) (58) Fields surveyed (Int. Cl. ⁷ , DB name) F01N 7/14 F01N 7/10 F02B 77/11

Claims (4)

(57) [Claims] 1. A soundproof and heat insulating structure, comprising: an exhaust manifold and a soundproof and heat insulating plate, wherein an air layer is provided between the soundproof and heat insulating plate and the exhaust manifold. A metal substrate formed into a predetermined three-dimensional shape, a nonwoven fabric provided on the surface of the metal substrate on the exhaust manifold side, and disposed on the surface of the nonwoven fabric and fixed to the metal substrate. A woven wire mesh, wherein the woven wire mesh makes the nonwoven fabric adhere to the metal substrate, and the woven wire mesh is made of a metal wire having a wire diameter of 0.1 to 1 mm, and has a mesh of 5 to 100 mesh. A soundproof and heat-insulating structure characterized by: 2. The metal substrate comprises a steel plate, a plated steel plate or a stainless steel plate having a thickness of 0.5 to 2 mm, and the nonwoven fabric comprises at least one inorganic fiber selected from ceramic fibers, glass wool, silica fibers or rock wool. 2. The soundproof and heat insulating plate according to claim 1, wherein the wire mesh is made of stainless steel, brass or galvanized steel. 3. The sound insulating and heat insulating board according to claim 1, wherein the nonwoven fabric has an average bulk density of 0.05 to 0.5 g / cm ³ , an average thickness of 0.5 to 15 mm, and an average compression ratio of 1% or more when assembled. 4. The woven wire mesh according to claim 1, wherein the woven wire mesh is fixed to the metal substrate at a fixed pitch of 10 to 100 mm, and the distance between the surface on the woven wire mesh side and the exhaust manifold is 5 to 50 mm. Sound insulation and heat shield.