JP3399427B2 - Sound insulation cover - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sound insulation cover suitable as a cover for shielding noise and heat from an exhaust manifold.

[0002]

2. Description of the Related Art In recent automobiles, electronic control has been advanced and various harnesses have been arranged near the exhaust manifold. Therefore, in order to prevent thermal deterioration of these harnesses, along the exhaust manifold, It has been widely adopted that a heat shield cover is provided to block heat radiation from the exhaust manifold. As the heat shield cover, as shown in FIG.
A plate-shaped outer panel 101 and an inner panel 102 having a heat insulating material 103 sandwiched therebetween are widely put into practical use.

However, depending on the engine, there is a problem that noise from the exhaust manifold is a problem, and in the heat shield cover, the inner panel acts as a noise reflection plate, so that the noise from the exhaust manifold is sufficiently blocked. There was a problem that I could not. Therefore, there has been proposed a technique for blocking the noise by using the heat shield cover. For example, in Japanese Utility Model Laid-Open No. 1-158513, a plurality of through holes are formed in an inner panel of the heat shield cover, a sound absorbing material is sandwiched between the inner panel and the outer panel, and noise is attenuated by the sound absorbing material. The sound insulation cover is shown. Usually, the heat insulating cover and the sound insulating cover are arranged along the exhaust manifold, so that the outer panel and the inner panel are molded into a shell-shaped three-dimensional shape by press molding.

[0004]

Since a so-called punching metal having through holes formed at predetermined intervals has a poor drawability, a plurality of through holes are formed like the sound insulating cover described in the above publication. When arranging the inner panel along the entire inner surface of the outer panel, the inner edge of the inner panel is provided with a band-like portion that does not form a through hole so that the outer edge of the inner panel is prevented from being damaged. There is. However, with such a configuration, it is not possible to use a general-purpose punching metal having through holes formed on the entire surface, and there is a problem that the manufacturing cost of the inner panel is significantly increased. Moreover, since the portion where the through hole is not formed contributes little to the improvement of the sound insulation performance, it is preferable to omit it in consideration of weight reduction and material cost reduction. Also, as a sound absorbing material,
Generally, a sheet-shaped inorganic fiber material is used, but such a sound-absorbing material does not have better drawability than the inner panel. There is a problem in that the adhesion to the panel is reduced and the sound insulation performance is reduced. Furthermore,
The outer panel and the inner panel are fixed to the exhaust manifold by bolts and the like at their four corners. However, this structure has a problem that surface vibration easily occurs in the central portion of the inner panel. In order to solve this problem, it may be possible to fix the central portion of the inner panel to the outer panel by spot welding or the like, but if a through hole is formed near the spot location, the bonding strength of both panels will decrease. There is.

An object of the present invention is to provide a sound insulation cover which can be manufactured at a low cost while ensuring sufficient sound insulation performance.

[0006]

A sound insulation cover according to a first aspect of the present invention is arranged close to an engine component as a noise source,
A sound insulation cover for blocking the transmission of noise to the outside, comprising an outer panel made of a plate-shaped member formed in a three-dimensional shape along the noise source, and a flat plate portion having no through hole.
It consists punching metal formed in a strip shape at a constant intervals, along the noise source side of the outer panel is provided only in a region corresponding to the gentle slope portion of the outer panel, plane smell
Those having a Louis down <br/> Napaneru fixed to the outer panel at a plurality of positions of the flat plate portion, and a sound absorbing material provided in layers between the outer panel and the inner panel Te.

A sound insulation cover according to a second aspect is a sound insulation cover which is disposed close to an engine part as a noise source and blocks transmission of noise to the outside, and is molded into a three-dimensional shape along the noise source. The outer panel made of a plate-shaped member and the flat plate portion not having the through holes are formed at regular intervals.
It consists punching metal formed in a strip shape provided along the noise source side of the outer panel, so as to correspond to a large portion of the diaphragm at the time of press molding is formed notches or notch, a plurality of flat portions in the plane and Louis N'napaneru fixed to the outer panel at a location, in which a sound absorbing material provided in layers between the outer panel and the inner panel.

According to a third aspect of the present invention, a noise-reducing convex portion is formed in a portion of the inner panel between adjacent through holes, and the through hole of the inner panel is formed. Forming an engaging portion by raising the opening edge of the sound absorbing material to the sound absorbing material side, and using, as the sound absorbing material, one formed by laminating at least two sound absorbing materials having different characteristics, As described in claim 6, the sound absorbing material on the inner panel side is made of a material harder than the sound absorbing material on the outer panel side, and the sound absorbing material on the inner panel side is formed on the outer panel side as described in claim 7. A material having higher heat resistance than the sound absorbing material, as described in claim 8,
Bending the outer edge of the inner panel to the outer panel side, and holding the outer edge of the sound absorbing material by this bent portion,
As described in claim 9, the outer panel, the sound absorbing material and the inner
Fix these three in the state of overlapping with the panel.
A punching hole is formed in the part and a pigeon is put in this hole.
Rukoto to combine these three wearing the main or rivets,
A preferred embodiment is that the noise source is the exhaust manifold of the engine as described in claim 10.

[0009]

In the sound insulation cover according to the first aspect, the noise from the engine part as the noise source is efficiently transmitted to the sound absorbing material side through the through hole of the inner panel, and the vibration energy in the sound absorbing material is thermal energy. Will be converted to and attenuated. Also, since the inner panel is provided in correspondence with the gentle slope of the outer panel,
A large drawing load does not act on the inner panel during press molding. Therefore, it is possible to use general-purpose punching metal as the inner panel,
It is possible to significantly reduce the manufacturing cost of the inner panel. Furthermore, the flat plate portion where the through hole is not formed is
Since the inner panel can be fixed to the outer panel by spot welding, rivets, eyelets, or the like, variations in the bonding strength between the fixing positions of the inner panel and the outer panel are reduced . Furthermore, the flat plate portion
-The surface rigidity of the panel is increased and the surface vibration of the inner panel is increased.
Since it is prevented, it is possible to further improve the sound insulation performance.
Become.

In the sound insulation cover according to the second aspect, the noise from the engine part as the noise source is efficiently transmitted to the sound absorbing material side through the through hole of the inner panel, and the vibration energy in the sound absorbing material is thermal energy. Will be converted to and attenuated. In addition, since the notch or notch is formed to correspond to the large drawing area of the inner panel during press forming, the inner panel is basically formed by bending, which results in a large drawing load. Does not work. Therefore, it is possible to use general-purpose punching metal as the inner panel,
It is possible to significantly reduce the manufacturing cost of the inner panel. Moreover, it is possible to increase the area of the inner panel and the sound absorbing material as much as possible to enhance the sound insulation effect. Furthermore, in the flat plate part where the through hole is not formed,
Since the panel can be fixed to the outer panel by spot welding, rivets, eyelets, or the like, there is less variation in the bonding strength between the fixing positions of the inner panel and the outer panel . Furthermore, the flat plate portion allows the surface of the inner panel to be
The rigidity is increased and the surface vibration of the inner panel is prevented.
Therefore, the sound insulation performance can be further enhanced.

As described in claim 3, by forming the sound-absorbing convex portion in the portion between the adjacent through holes of the inner panel, the sound insulation performance can be further enhanced. When the opening edge of the through hole of the inner panel is raised to the sound absorbing material side to form the locking portion, the sound absorbing material is laminated between the inner panel and the outer panel. The locking portion bites into the sound absorbing material, and the relative movement of the inner panel and the sound absorbing material is restricted, and the surface vibration of the inner panel is effectively prevented. As described in claim 5, when at least two sound absorbing materials having different characteristics are laminated as the sound absorbing material, for example, as in claim 6,
By constructing the sound absorbing material on the inner panel side with a material that is harder than the sound absorbing material on the outer panel side, the sound insulation frequency band is expanded, and as the sound absorbing material, ceramic fiber, glass wool, silica fiber, rock wool, etc. When the sheet-shaped inorganic fiber material is used, the problem that the sound absorbing material scatters and scatters can be suppressed. Further, when the sound absorbing material on the inner panel side is made of a material having higher heat resistance than the sound absorbing material on the outer panel side as described in claim 7, the heat absorbing material has sufficient heat resistance and its manufacturing cost is reduced. It can be reduced. In other words, as the sound absorbing material on the inner panel side, a sound absorbing material that emphasizes heat resistance rather than material cost is adopted, and as the sound absorbing material on the outer panel side, a material that is slightly inferior in heat resistance but cheap is used The manufacturing cost can be reduced while sufficiently ensuring the heat resistance of the material.

When the outer edge portion of the inner panel is bent toward the outer panel side and the outer edge portion of the sound absorbing material is held by this bent portion, the inorganic fiber material as described above is used as a sound absorbing sheet. It is possible to prevent the problem that the sound absorbing material is scattered from the side edge and falls off when the shaped material is used. As described in claim 9, an outer panel and
With the sound absorbing material and the inner panel overlaid,
The punching holes are formed in the fixed parts of the three
Attach eyelets or rivets to the insertion holes to connect these three
When combined, the bonding strength of both panels can be further improved. When the sound insulation cover is provided on the exhaust manifold of the engine as described in claim 10, the noise from the exhaust manifold can be effectively attenuated by the sound absorbing material, and the heat radiation from the exhaust manifold can be effectively blocked by the sound absorbing material.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. The present embodiment is a case where the present invention is applied to a sound insulating cover that covers an exhaust manifold of an engine. As shown in FIG. 1, on the outside of the exhaust manifold EM of the engine E, a sound insulating cover 1 for blocking noise and heat from the exhaust manifold EM is attached via a plurality of bolts B so as to cover the exhaust manifold EM. Has been. However, the shape and size of the sound insulation cover 1 are set according to the shape and size of the exhaust manifold EM. As shown in FIGS. 1 to 4, the sound insulation cover 1 includes an outer panel 2 that is three-dimensionally formed so as to cover the exhaust manifold EM, and an inner panel provided along the surface of the outer panel 2 on the exhaust manifold EM side. The panel 3 and the sound absorbing material 4 mounted in a laminated shape between the outer panel 2 and the inner panel 3 are provided.

The outer panel 2 is manufactured by press forming a steel plate plated with aluminum, and basically,
Front wall portion 10 arranged on the front side of the exhaust manifold EM
And a side wall portion 11 arranged on both left and right sides of the exhaust manifold EM and an upper wall portion 12 arranged on the upper side of the exhaust manifold EM, and an upper portion thereof is leftward depending on the shape of the exhaust manifold EM. A protruding bulge portion 13 is formed. However, the outer panel 2 may be made of a stainless steel plate or other material depending on the usage conditions and the like.

The front wall portion 10 and the upper wall portion 1 of the outer panel 2
The outer panel 2 is formed with a gentle sloping portion 14 including both wall portions 10 and 12 while being gently inclined and smoothly connected to each other. Also, the outer panel 2 has
Elastic support members 30 for elastically supporting the sound insulation cover 1 on the exhaust manifold EM are provided at three locations on the front wall portion 10 and the upper wall portion 1.
It is installed in 5 places, 2 places in 2 places. However, the number and arrangement of the elastic support members 30 are appropriately set according to the shape and size of the exhaust manifold EM.

As shown in FIGS. 2 to 5, the inner panel 3 is basically formed in a shape corresponding to the gently sloping portion 14 of the outer panel 2, but the front wall portion 10 of the outer panel 2 is formed. At the position corresponding to
The avoidance notch 20 for avoiding the above is formed, and the front wall portion 10 and the upper wall portion 1 in the bulging portion 13 of the outer panel 2 are formed.
At the position corresponding to the boundary with 2, the inner panel 3
A cutout 21 is formed to reduce the amount of drawing, and a bent portion 22 that is bent toward the outer panel 2 is formed at the outer edge portion. This inner panel 3 is not a general-purpose punching metal in which through holes 23 are formed at regular intervals on the entire surface, but such a punching metal is used.
In the flat plate portion where the through holes 23 are not formed,
Using punching metal formed into strips at intervals, the punching metal is plated with aluminum and punched into a shape as shown in FIG. 5, and then, along the outer panel 2 as shown in FIG. It is manufactured by press forming into a curved shape. However, the inner panel 3 may be made of a stainless steel plate or other material depending on the usage conditions and the like.

As shown in FIGS. 2 to 6, the sound absorbing member 4 is made of a sheet-shaped member having an outer shape substantially the same as that of the inner panel 3, and is made of ceramic fibers, glass fibers, silica fibers, mineral fibers (lock). Wool) and so on.
If the thickness of the sound absorbing material 4 is less than 0.5 mm, sound absorbing performance and heat shielding performance cannot be sufficiently obtained, and if it exceeds 15 mm, it is difficult to mount in a narrow restricted space in the engine E room. Therefore, it is set to 0.5 to 15 mm. The sound absorbing material 4 itself can be used without any problem as long as it has a heat resistance of 500 ° C. or higher. If heat resistance is not important, glass fiber (heat resistance of about 550 ° C.) is used from the viewpoint of cost and heat resistance is required. Heat resistance of 1000
Ceramic fibers above ℃ will be used. Also,
As the ceramic fiber, alumina ceramic, silica-alumina ceramic, or the like can be used.

The inner panel 3 and the sound absorbing material 4 are fixed to the outer panel 2 with a flat plate portion of the inner panel 3 with the sound absorbing material 4 being sandwiched between the inner panel 3 and the outer panel 2. It is fixed to the outer panel 2 by spot welding at 5. In this way, since the inner panel 3 and the sound absorbing material 4 are fixed by spot welding, as shown in FIGS. 6 and 7, the sound absorbing material 4 is provided with the opening 25 corresponding to the fixed portion 5 by spot welding. The inner panel 3 and the outer panel 2 are electrically connected to each other through the opening 25. Further, in order to prevent the strength of the inner panel 3 in the fixed portion 5 from decreasing and to reduce the variation in the bonding strength between the panels 2 and 3 due to spot welding, the inner panel 3 has a washer 26 on its exhaust manifold EM side surface. Is placed on the outer panel 2 together with the washer 26.

The elastic support 30 will be described with reference to FIG.
As shown in, the exhaust manifold E of the outer panel 2
A mounting hole 15 is formed at the fastening position of the bolt B with respect to M, and a sleeve 31 with a collar is mounted in the mounting hole 15 from the inner surface side of the outer panel 2, and the tubular portion of the sleeve 31 on the outer surface side of the outer panel 2. From the outer panel 2 side, an elastic body 33 formed by bundling fine metal wires into an annular shape and a washer 34 for retaining are externally fitted and attached to the outer panel 2, and the sleeve 31, the elastic body 33, and the washer form a tubular portion. It is fixed to the outer panel 2 by crimping the tip of 32. The outer panel 2 is elastically supported by the exhaust manifold EM via the elastic body 33 in a state where the bolt B is inserted through the sleeve 31 and the outer panel 2 is fixed to the exhaust manifold EM. The elastic body 33
As the material, a material made of synthetic rubber or a synthetic resin material may be used, or a disc spring, a coil spring, or the like may be used. Further, like the elastic support 30A shown in FIG. 9, the sleeve 35 is fitted onto the tubular portion 32 so that the distance between the washer 34 and the flange portion 36 of the sleeve 31 does not change when the tubular portion 32 is crimped. It may be configured as follows. Further, the avoidance notch 20 is omitted, and the portion of the inner panel 3 corresponding to the avoidance notch 20 is directly overlapped with the outer panel 2 without the sound absorbing material 4 interposed, and the elastic support tool is provided. It is also possible to provide 30. In this case,
Since the inner panel 3 and the outer panel 2 are joined by the elastic support tool 30, it is possible to minimize the number of joints between the panels 2 and 3 by spot welding or the like.

Next, the operation and effect of the sound insulation cover 1 will be described. The noise from the exhaust manifold EM is efficiently transmitted to the sound absorbing material 4 side through the through hole 23 of the inner panel 3, and the vibration energy is converted into heat energy in the sound absorbing material 4 and attenuated. Also,
The heat radiation from the exhaust manifold EM is effectively blocked by the sound absorbing material 4. Since the inner panel 3 is provided so as to correspond to the gently sloped portion 14 of the outer panel 2, a large drawing load does not act on the inner panel 3 during press molding. Therefore, a general-purpose punching metal can be used as the inner panel 3, and the manufacturing cost of the inner panel 3 can be significantly reduced.

Since the sound absorbing material 4 is sandwiched between the inner panel 3 and the outer panel 2 which are made of punched metal, the inner panel 3 is compared with the case where the sound absorbing material 4 is fixed to the outer panel 2 by a metal net or the like. It becomes possible to strongly adhere to the sound absorbing material 4, and it is possible to effectively prevent surface vibration of the inner panel 3. Although an inorganic fiber material is used as the sound absorbing material 4, the sound absorbing outer portion 4 is planarly supported by the inner panel 3, and the outer edge portion is held by the bent portion 22 of the outer edge portion of the inner panel 3. Therefore, there is almost no problem that the sound absorbing material 4 is scattered and drops off due to vibration from the engine E or the like. Through holes 23 are formed as the inner panel 3.
Breads that are formed into strips at regular intervals
Since it is made of chinging metal,
And fix the inner panel 3 to the outer panel 2
Therefore, the inner panel 3 and the outer panel 2 are joined together.
It is possible to stabilize the strength, and the flat plate part
The surface rigidity of the inner panel 3 is increased, and the inner panel is
Since the surface vibration of 3 is prevented, it is possible to further improve the sound insulation performance.
And are possible.

Next, another embodiment in which the structure of the sound insulation cover 1 is partially changed will be described. (1) The inner panel 3 and the sound absorbing material 4 are independently provided at the positions corresponding to the left and right side wall portions 11 of the outer panel 2.
An inner panel made of punch metal and a sound absorbing material made of the same material as described above may be provided to increase the area of the sound absorbing material occupying the inner surface of the outer panel 2 as much as possible to enhance the sound insulation performance and the heat insulation performance.

(2) Like the sound insulation covers 1A and 1B shown in FIGS. 10 and 11, the inner panel 3 is provided with the avoidance notch 20 and the avoidance notch 40 corresponding to the elastic support 30.
And a plurality of cutouts 21 for reducing the drawing amount of the inner panel 3 are formed.
0 and 21 are formed from the outer end portion of the inner panel to the position corresponding to the gentle slope portion 14, and the sound absorbing material 4 is formed in substantially the same outer shape as that of the inner panel 3, so that substantially the entire inner surface of the outer panel 2 is formed. The inner panel 3 and the sound absorbing material 4 may be arranged respectively, and the area of the sound absorbing material 4 occupying the inner surface of the outer panel 2 may be increased as much as possible to enhance the sound insulation performance and the heat insulation performance. In addition, in this case, FIG.
As shown in FIG. 2, the outer edge portion of the outer panel 2 is bent inward to hold the outer edge portion of the inner panel 3, and the inner panel 3 and the sound absorbing material 4 are fixed to the outer panel 2, respectively. However, the inner panel 3 may be fixed to the outer panel 2 by using spot welding together. Further, in the state where the notch 21 is formed in the inner panel 3 and the notch is formed, and the inner panel 3 is press-molded into a shape along the inner surface of the outer panel 2, the inner panel 3 is provided on both sides of the notch. May be configured to overlap.

(3) As shown in FIGS. 13 and 14, both panels 2 and 3 may be fixed by eyelets 41 or rivets 42 instead of spot welding. With this configuration, it is possible to further increase the bonding strength at the fixing portion 5 of both panels 2 and 3. Further, in this case, as shown in FIG. 15, the opening 25 is not formed in the sound absorbing material 4, and the outer panel 2, the sound absorbing material 4, and the inner panel 3 are superposed on each other and punched in the fixing portion 5. To form the insertion hole 43, and the eyelet 41 and the rivet 4 are inserted into the insertion hole 43.
The sound absorbing member 4 and the inner panel 3 may be fixed to the outer panel 2 by mounting the sound absorbing member 4 on the outer panel 2. (4) As shown in FIG. 16, a fixing portion 44 that does not form the through hole 23 is formed in the fixing portion 5 of the inner panel 3 with respect to the outer panel 2, and at this fixing portion 44, spot welding, eyelets 41, rivets 42, etc. are used. Both panels 2 and 3 may be combined. In this case, although the manufacturing cost of the inner panel 3 increases, it is possible to prevent the inner panel 3 from being damaged at the fixing portion 5 and stabilize the bonding strength between the inner panel 3 and the outer panel 2. Become.

(5 ) As shown in FIG. 17, by forming the through hole 23 of the inner panel 3 by burring or the like, a cylindrical shape extending toward the sound absorbing material 4 is formed at the edge of the through hole 23 of the inner panel 3. The surface vibration of the inner panel 3 is regulated by engaging the sound absorbing member 4 with the sound absorbing member 4 formed between the panels 2 and 3 with the engaging member 45 formed. You may comprise. ( 6 ) As shown in FIG. 18, even if the sound absorbing performance is further enhanced by forming a sound absorbing and noise absorbing convex portion 46 projecting toward the exhaust manifold EM side between the through holes 23 of the inner panel 3. Good.

( 7 ) The sound absorbing material 4 may be composed of a sound absorbing material having a multilayer structure in which a plurality of sound absorbing materials having different characteristics are laminated.
For example, as shown in FIG. 19, instead of the sound absorbing material 4, a sound absorbing material 4A having a two-layer structure of a sound absorbing material 47 on the inner panel 3 side and a sound absorbing material 48 on the outer panel 2 side is provided, and the sound absorbing material on the inner panel 3 side is provided. The material 47 is made of a material harder than the sound absorbing material 48 of the outer panel 2 to more effectively prevent the inorganic fiber material constituting the sound absorbing material 4A from falling off from the through holes 23, and to reduce the frequency range capable of sound insulation. It may be enlarged. Further, the sound absorbing material 47 on the inner panel 3 side is made of a material having excellent heat resistance, and the sound absorbing material 48 on the outer panel 2 side is made of a material which is slightly inferior in heat resistance but is inexpensive. The manufacturing cost may be reduced while sufficiently ensuring the heat resistance of the. Further, as the sound absorbing material 47 on the inner panel 3 side, a ceramic fiber, a glass fiber, or a sheet material in which these fibers and metal thin wires are knitted or woven is used, and the inorganic fiber material forming the sound absorbing material 4A falls off from the through hole 23. This may be prevented.

In this embodiment, the exhaust manifold EM is used.
Although the present invention is applied to the sound insulation covers 1, 1A, and 1B, the present invention can be similarly applied as a sound insulation cover for engine parts other than the exhaust manifold EM.

[0028]

According to the sound insulating cover of the first aspect, it is possible to use a general-purpose punching metal as the inner panel, and it is possible to significantly reduce the manufacturing cost of the inner panel. Also, the inner panel is
For example, it is arranged in the center of the outer panel and is not provided in a portion corresponding to the outer peripheral portion of the outer panel, but even in the conventional case, a portion having no through hole of the inner panel is arranged in that portion. Therefore, the sound insulation performance is not significantly reduced as compared with the conventional sound insulation cover. Further, by forming the flat plate portion in which the through hole is not formed on the inner panel, it is possible to reduce the variation in the bonding strength at the fixing portion between the outer panel and the inner panel. Furthermore, the flat plate portion
-The surface rigidity of the panel is increased and the surface vibration of the inner panel is increased.
Since it is prevented, it is possible to further improve the sound insulation performance.
Become.

According to the sound-insulating cover of the second aspect, it is possible to use a general-purpose punching metal with a simple structure in which the notch or notch is formed in correspondence with the large aperture of the inner panel. It is possible to significantly reduce the manufacturing cost of the inner panel. Moreover,
It is possible to increase the sound insulation effect by increasing the areas of the inner panel and the sound absorbing material as much as possible. Further, by forming the flat plate portion in which the through hole is not formed in the inner panel, it is possible to reduce the variation in the bonding strength at the fixing portion between the outer panel and the inner panel. Furthermore,
The flatness enhances the surface rigidity of the inner panel,
Since the surface vibration of the gate panel is prevented, the sound insulation performance is further improved.
It is possible to raise it.

According to the third aspect of the invention, the sound insulation performance can be further enhanced by the convex portion formed on the inner panel. According to the fourth aspect of the invention, the locking portion formed at the opening edge of the through hole of the inner panel restricts the relative movement of the inner panel and the sound absorbing material,
The surface vibration of the inner panel can be effectively prevented.

According to the sixth aspect of the invention, it is possible to expand the frequency band capable of sound insulation and prevent the sound absorbing material from scattering and scattering. According to the seventh aspect of the invention, as the sound absorbing material on the inner panel side, a sound absorbing material that emphasizes heat resistance rather than material cost is adopted, and as the sound absorbing material on the outer panel side, heat resistance is slightly inferior, but from inexpensive material. By using such a material, the manufacturing cost can be reduced while sufficiently ensuring the heat resistance of the sound absorbing material.
According to the eighth aspect of the invention, when the sheet-shaped inorganic fiber material such as ceramic fiber, glass wool, silica fiber or rock wool is used as the sound absorbing material, the sound absorbing material is scattered from the side edge. The problem of falling off can be prevented. According to the ninth aspect of the present invention , the strength of the connection between the outer panel and the inner panel is improved.
The layers can be improved. According to the tenth aspect, the noise from the exhaust manifold can be effectively attenuated by the sound absorbing material, and the heat radiation from the exhaust manifold can be effectively blocked by the sound absorbing material.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view of a sound insulation cover assembled to an exhaust manifold.

FIG. 2 is an exploded perspective view of the sound insulation cover.

[Figure 3] Rear view of the sound insulation cover

FIG. 4 is a vertical sectional view of the sound insulation cover.

FIG. 5 is a front view of the inner panel in a deployed state.

FIG. 6 is a front view of the sound absorbing material in a developed state.

FIG. 7 is a vertical cross-sectional view of the sound insulation cover at the fixed portion.

FIG. 8 is a vertical cross-sectional view of a portion fixed to the exhaust manifold.

FIG. 9 is a vertical cross-sectional view of another embodiment of a fixing portion for an exhaust manifold.

FIG. 10 is an exploded perspective view of a sound insulation cover according to another embodiment.

FIG. 11 is an exploded perspective view of a sound insulation cover according to another embodiment.

FIG. 12 is a vertical cross-sectional view of the vicinity of the outer edge of the sound insulation cover.

FIG. 13 is a vertical cross-sectional view of a sound insulation cover at a fixing portion of another embodiment.

FIG. 14 is a vertical cross-sectional view of a sound insulation cover at a fixing portion of another embodiment.

FIG. 15 is a vertical cross-sectional view of a sound insulation cover at a fixing portion of another embodiment.

FIG. 16 is a perspective view of a main part of an inner panel of another embodiment.

FIG. 17 is a vertical sectional view of an inner panel according to another embodiment.

FIG. 18 is a vertical sectional view of an inner panel of another embodiment.

FIG. 19 is a vertical sectional view of an inner panel of another embodiment.

FIG. 20 is a vertical sectional view of a conventional sound insulation cover.

[Explanation of symbols]

E Engine EM Exhaust Manifold B Bolt 1 Sound Insulation Cover 2 Outer Panel 3 Inner Panel 4 Sound Absorbing Material 5 Fixed Part 10 Front Wall Part 11 Side Wall Part 12 Upper Wall Part 13 Swelling Part 14 Sloping Part 15 Mounting Hole 20 Avoidance Notch 21 Notch 22 Bent 23 Through hole 25 Opening 26 Washer 30 Elastic support 31 Sleeve 32 Tube 33 Elastic 34 Washer 30A Elastic support 35 Sleeve 36 Collar 1A Sound insulation cover 1B Sound insulation cover 40 Avoidance cutout 41 Eyelet 42 rivet 43 insertion hole 44 fixing part 45 engaging part 46 convex part 4A sound absorbing material 47 sound absorbing material 48 sound absorbing material

─────────────────────────────────────────────────── ─── Continuation of front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) F02B 77/11 F02B 77/13

Claims (10)

(57) [Claims] 1. A sound insulation cover, which is disposed close to an engine component as a noise source and blocks transmission of noise to the outside, and is an outer panel made of a plate-shaped member formed in a three-dimensional shape along the noise source. And the flat plate part without through holes is striped at regular intervals
Consists formed was punched metal to, provided only in a region corresponding to the gentle slope portion of the outer panel along the noise source side of the outer panel, a plurality of locations of the flat portion in the plane
In sound insulation cover with a Louis N'napaneru fixed to the outer panel, and a sound absorbing material provided in layers between the outer panel and the inner panel. 2. A sound insulation cover, which is arranged close to an engine part as a noise source and blocks transmission of noise to the outside, and is an outer panel made of a plate-shaped member formed in a three-dimensional shape along the noise source. And the flat plate part without through holes is striped at regular intervals
Consists formed was punched metal to, provided along the noise source side of the outer panel, so as to correspond to a large portion of the diaphragm at the time of press molding is formed notches or notch, a plurality of locations of the flat portion in the plane in sound insulation cover with a Louis N'napaneru fixed to the outer panel, and a sound absorbing material provided in layers between the outer panel and the inner panel. 3. The sound insulation cover according to claim 1, wherein a sound absorbing convex portion is formed in a portion between the adjacent through holes of the inner panel. 4. The sound insulation cover according to claim 1, wherein an opening edge of the through hole of the inner panel is raised toward the sound absorbing material to form a locking portion. 5. At least two sound absorbing materials having different characteristics
The sound insulation cover according to any one of claims 1 to 4, wherein the sound insulation cover is formed by laminating a plurality of sound absorbing materials. 6. The sound insulation cover according to claim 5, wherein the sound absorbing material on the inner panel side is made of a material harder than the sound absorbing material on the outer panel side. 7. The sound insulation cover according to claim 5, wherein the sound absorbing material on the inner panel side is made of a material having higher heat resistance than the sound absorbing material on the outer panel side. 8. The sound insulation cover according to claim 1, wherein the outer edge portion of the inner panel is bent toward the outer panel side, and the outer edge portion of the sound absorbing material is held by the bent portion. 9. An outer panel, a sound absorbing material, and an inner panel
With the upper part of the
Hole to form an insertion hole, and then insert eyelets or
9. A bed is attached to combine these three parties.
The sound insulation cover according to any one of items. 10. The sound insulation cover according to claim 1, wherein the noise source is an exhaust manifold of the engine.