JP3147611B2 - Exhaust pipe heat shield structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat shield structure for an exhaust pipe, and more particularly to a heat shield structure for an exhaust pipe which reduces radiation noise caused by the heat shield structure.

[0002]

2. Description of the Related Art Conventionally, as a heat shielding structure for an exhaust pipe connected to an engine of an automobile or the like, for example, as shown in FIG.
A heat shield plate 13 is provided on the exhaust pipe 11 via a bracket 12 on the side where heat shielding is required, and an air layer 14 is provided between the heat shield plate 13 and the exhaust pipe 11. The heat transmitted from the exhaust pipe 11 is blocked by the heat shield plate 13 via the air layer 14 so as not to spread outside the heat shield plate 13. However, since the heat shield plate 13 is generally formed of a thin steel plate, noise radiated from the heat shield plate itself due to vibration propagation from the exhaust pipe 11 has been a problem.

Therefore, as a solution to the above radiated sound, there is a proposal of a double structure in which two heat shield plates 13 are stacked. With respect to vibration (resonance) accompanying a cross-sectional change occurring in the heat shield plate 13, the vibration is attenuated by friction between the heat shield plates to reduce radiated sound. However, even if the heat shield plate 13 has a double structure, the radiation noise has not yet been effectively reduced, and there is also a problem of radiation noise generated from the exhaust pipe itself.

[0004]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a heat shield for an exhaust pipe in which the heat shield of the exhaust pipe is satisfactorily performed and radiation noise caused by the heat shield structure of the exhaust pipe is reduced. It is to provide a structure.

[0005]

In order to achieve the above object, a heat shielding structure for an exhaust pipe according to the present invention is provided with a metal covering member provided on a bracket through a bracket, and the heat shielding side of the covering member is provided with the exhaust. An air layer is interposed between the exhaust pipe and the air layer, and the non-heat-shielding side is disposed so as to be in close contact with the exhaust pipe. It is characterized in that the body is formed from a braided cloth-like material.

[0006]

The present invention is constructed as described above, and the covering member in contact with the exhaust pipe and the bracket is formed from a braided thin metallic linear body. The linear body is displaced following the movement of the vibration transmitted from the exhaust pipe and the bracket, and a large internal damping effect occurs on the covering member due to friction generated at a contact portion where the metallic linear bodies come into contact with each other, and the covering member itself No radiated sound is generated. Also, a covering member formed of a cloth-like material obtained by braiding a thin metal linear body through a bracket on the exhaust pipe is provided,
Since an air layer is interposed between the cover member and the exhaust pipe on the heat shield side, heat released from the exhaust pipe can be effectively blocked by the cover member via the air layer.

Further, since the covering member on the non-heat shield side is held in close contact with the exhaust pipe, even if the exhaust pipe resonates at a predetermined frequency, a thin metal wire of a braided cloth-like material forming the covering member is formed. The body is displaced following the movement of the exhaust pipe, and the vibration of the exhaust pipe can be attenuated by the friction generated at the contact portion between the metal linear bodies.

[0008]

Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is an explanatory sectional view of a heat shielding structure of an exhaust pipe according to the present invention. Reference numeral 1 denotes an exhaust pipe connected to an engine or the like (not shown), reference numeral 2 denotes a bracket provided on the heat shield side A of the outer surface of the exhaust pipe 1, and reference numeral 3 denotes a metal cover member for heat shield. The thermal structure is such that the exhaust pipe 1 is covered by the covering member 3 via the bracket 2, and the heat shielding side A of the covering member 3 is connected to the exhaust pipe 1.
An air layer 4 is interposed between the exhaust pipe 1 and the non-heat-shielding side B so as to be in close contact with the surface of the exhaust pipe 1 so as to apply tension to the covering member 3 and hold it.

As shown in FIG. 2, the covering member 3 is formed of a cloth-like material obtained by tightly braiding a thin metal linear body 5 such as a metal wire or a thin band without any gap. As the metal linear body 5, any conventionally known metal that can block heat radiated from the exhaust pipe can be used. For example, a steel wire or a thin steel band can be preferably used. The braided structure of the metal linear members 5 may be, for example, a structure in which a plurality of metal linear members 5 arranged in parallel can be braided so as to be orthogonal to each other, but is not limited thereto. In addition, the covering member 3
There is no particular limitation on the arrangement direction of the metal linear bodies 5 when the exhaust pipe 1 is covered with, for example, the metal linear bodies 5 cross the vibration transmission direction of the exhaust pipe 1 in the opposite direction at an equal angle. Can be mounted as follows.

As described above, according to the present invention, since the entire covering member 3 is formed of a cloth-like material obtained by braiding the thin metal linear member 5, the contact holding portion 8 of the covering member 3 and the bracket which are in close contact with the exhaust pipe 1 are provided. The metal linear body 5 is displaced following the movement of the vibration transmitted from the abutting portion 9 abutting on the metal member 2, and a large internal space is formed in the covering member 3 by the friction generated at the contact portion where the metal linear bodies 5 come into contact with each other. The damping effect occurs, and the vibration of the covering member 3 itself is suppressed, so that no radiated sound is generated from the covering member 3.

Further, a covering member 3 formed of a cloth-like material obtained by braiding a thin metal linear body 5 via a bracket 2 is provided on the exhaust pipe 1, and the heat shielding side of the covering member 3 is connected to the exhaust pipe 1. Since the air layer 4 is interposed in the air, heat released from the exhaust pipe 1 can be reliably blocked by the covering member 3 via the air layer 4. Further, since the non-heat shielding side covering member 3 is held in close contact with the exhaust pipe 1, even if the exhaust pipe 1 resonates at a predetermined frequency, the metal linear body follows the movement of the exhaust pipe 1. The vibration of the exhaust pipe 1 can be attenuated by friction between the metal linear bodies 5 caused by the displacement of the exhaust pipe 5, and the radiation noise caused by the vibration of the exhaust pipe 1 can also be reduced.

FIG. 3 shows another embodiment of the present invention. In the embodiment described above, the portion on the heat shield side A of the covering member 3 via the air layer 4 is formed of metal plates 6a and 6b made of steel or the like, and the metal plates 6a and 6b are fixed by fixing members 7 such as bolts. The cover member 3 is fixed and the non-heat-shielding side B of the covering member 3 is held in close contact with the surface of the exhaust pipe 1. Exhaust pipe 1 transmitting vibration and covering member 3 not in contact with bracket 2
Is composed of metal plates 6a and 6b having a lower internal damping effect than a cloth-like material obtained by braiding a thin metal linear body 5, that is, at least a close contact holding portion 8 and a bracket 2 that hold the exhaust member 1 in close contact with the exhaust pipe 1. Also, the vibration transmitted from the exhaust pipe 1 and the bracket 2 can reduce the vibration of the thin metal linear body 5 of the covering member 3 by forming the contact portion 9 with the cloth material formed by braiding the thin metal linear body 5. It can be attenuated by the braided cloth-like material, and the same effects as above can be obtained.

[0013]

As described above, according to the present invention, the metal covering member provided on the exhaust pipe via the bracket is provided with a thin metal linear member for the contact holding portion with the exhaust pipe and the contact portion with the bracket. Is formed from a braided cloth-like material, whereby the thin metal linear body of the cloth-like substance is displaced following the movement of the vibration transmitted from the exhaust pipe and the bracket, and an internal part generated by friction between the metal linear bodies is formed. Due to the damping effect, radiated sound generated from the covering member can be prevented. In addition, since an air layer is interposed on the heat shield side of the covering member formed of a cloth material formed by braiding a thin metal linear body, heat released from the exhaust pipe is effectively blocked by the covering member via the air layer. be able to. Furthermore, since the non-heat shielding side covering member is held in close contact with the exhaust pipe, even if the exhaust pipe resonates at a predetermined frequency,
The thin metal linear body of the covering member is displaced to follow the movement of the exhaust pipe, and the radiation noise generated from the exhaust pipe can be reduced.

[Brief description of the drawings]

FIG. 1 is an explanatory sectional view showing a heat shielding structure of an exhaust pipe according to the present invention.

FIG. 2 is a plan view of a main part of the covering member of FIG. 1;

FIG. 3 is an explanatory cross-sectional view showing another example of the heat shielding structure of the exhaust pipe according to the present invention.

FIG. 4 is an explanatory view showing a conventional heat shielding structure of an exhaust pipe.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Exhaust pipe 2 Bracket 3 Covering member 4 Air layer 5 Metal linear body 8 Close contact holding part 9 Contact part

Claims (1)

(57) [Claims] An exhaust pipe is provided with a metallic covering member via a bracket, a heat shield side of the covering member is interposed between the exhaust pipe and an air layer, and a non-heat shield side is provided on the exhaust pipe. A heat-shielding structure for an exhaust pipe, which is disposed so as to be in close contact with each other, and in which at least a contact holding portion of the covering member and a contact portion with the bracket are formed of a cloth formed by braiding a thin metal linear body.