JP3127681B2 - How to install the exhaust pipe damper - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of mounting a damper for an exhaust pipe for reducing radiation noise caused by vibration of an exhaust pipe connected to an internal combustion engine.

[0002]

2. Description of the Related Art Conventionally, in a vehicle equipped with an internal combustion engine, such as an automobile or a motorcycle, when the vibration of the internal combustion engine is transmitted to an exhaust pipe, a radiation noise is generated from the exhaust pipe, causing noise. The present inventors, as shown in FIG. 2, the surface of the exhaust pipe 1 having an outer diameter d _1, so that the inner diameter substantially equal d ₂ to the outer diameter d _1, knitting or weaving a metal wire such as steel wire Through the damper 2 formed as shown by the arrow A,
By welding in a state where they are in contact with each other, the exhaust pipe 1
We found a way to reduce the sound radiated from

[0003] This is because the vibration transmitted from the internal combustion engine to the exhaust pipe 1 is transmitted to a damper 2 in contact with the exhaust pipe 1, and the metal wires forming the damper 2 are vibrated so that the woven metal wires are connected to each other. The vibration is attenuated by generating friction between the metal wire and the surface of the exhaust pipe 1 and converting vibration energy into heat energy.

[0004]

However, merely bringing the damper into contact with the surface of the exhaust pipe as described above cannot sufficiently exert the vibration damping effect of the damper, and in particular receives heat and vibration energy. As a result, it has been found that when the metal wire forming the damper is elongated, the adhesion between the exhaust pipe and the damper is deteriorated, and a problem of losing the vibration damping effect occurs.

[0005] In view of the above problems, the present invention makes it possible to sufficiently exhibit the vibration damping effect of a damper by strongly adhering a damper formed by weaving a metal wire to an exhaust pipe. It is an object of the present invention to provide a method of mounting a damper for an exhaust pipe without losing a vibration damping effect even when a constituent metal wire is elongated.

[0006]

According to the present invention, there is provided a method for mounting a damper for an exhaust pipe according to the present invention. Preparing the damper, elastically expanding the inner diameter of the damper, fitting the damper so as to cover the surface of the exhaust pipe, and fixing the damper in a state of being pressed against the surface of the exhaust pipe. Is the way.

As the damper, a wire blade or the like in which a metal wire such as a steel wire is woven in a mesh shape in a direction intersecting the longitudinal direction of the exhaust pipe is suitable. Let each other rub each other. When this damper is elastically expanded, the inner diameter may be expanded by compressing the damper in the axial direction and the reaction force thereof, or at first, only one end of the damper may be expanded to exhaust pipe. And the damper may be pushed in the longitudinal direction of the exhaust pipe to gradually increase the expanded portion.

[0008] As a means for fixing the damper, welding is most suitable. In addition, brazing may be employed, or a bracket may be attached to the damper and the exhaust pipe, and these may be riveted. May be fixed.

[0009]

According to the exhaust pipe damper mounting method of the present invention, the damper is temporarily elastically deformed to expand its inner diameter, and when the damper is fitted to the exhaust pipe, its elastic restoring force is reduced. Since it can be used as a pressing force to the exhaust pipe, the vibration energy of the exhaust pipe can be easily transmitted to the damper, and the vibration damping action can be enhanced.

Further, even if the metal wire forming the damper is stretched by receiving heat or vibration energy, only a slight reduction in the pressing force acting on the surface of the exhaust pipe causes the damper to be in close contact with the surface of the exhaust pipe. Therefore, loss of the vibration damping effect can be prevented.

[0011]

[Embodiment] Next, an embodiment of a method of mounting an exhaust pipe damper according to the present invention will be described with reference to the drawings. First, as shown in FIG. 1, in the present embodiment, a plurality of metal wires (steel wires) bundled in a belt shape are used as warp yarns and weft yarns, respectively, and these are woven into a tubular shape by weaving them at right angles to each other. Was formed as a damper 2. The direction of the composition of the metal wire forming the damper 2 is arranged so as to obliquely intersect the longitudinal direction of the exhaust pipe, and the inner diameter of the damper 2 is free from stress. Is set to d ₂ in this state, and is set to be smaller than the outer diameter of an exhaust pipe (not shown).

In mounting the damper 2, first, both ends of the damper 2 in the axial direction are compressed and shrunk as shown by an arrow B, and deformed as shown by a chain line C in the figure to reduce the axial length. Instead, it expands to an inner diameter d ₂ ′ that is larger than the outer diameter of the exhaust pipe. Next, while maintaining this state, an exhaust pipe (not shown) is inserted into the damper 2 to a predetermined position to remove the force pressing the damper 2 in the axial direction.

Then, an elastic restoring force acts on the damper 2 and attempts to return to the original shape, so that the damper 2 is pressed against the surface of the exhaust pipe. The damper 2 in this state
Has the same inner diameter as the outer diameter of the exhaust pipe, and cannot return to d _2, so that the elastic restoring force corresponding to that becomes the pressure bonding force to the exhaust pipe. Next, in this embodiment, both ends in the axial direction of the damper 2 are welded to the exhaust pipe and integrally fixed while the elastic restoring force of the damper 2 itself acts on the exhaust pipe as described above.

During operation of the internal combustion engine, vibration is transmitted to the exhaust pipe, and this vibration is transmitted to the damper 2 which is in close contact with the surface of the exhaust pipe. And since this damper 2 is constituted by weaving a steel wire,
The woven steel wires rub against each other where they overlap, causing friction. Similar friction will also occur between the steel wire and the surface of the exhaust pipe. Due to this friction, vibration energy is converted to heat energy, and vibration of the exhaust pipe is suppressed, and radiation noise is also reduced.

[0015] Even if the steel wire forming the damper 2 is stretched due to the influence of heat or vibration, the above-described crimping force acts, so that the damper 2 comes into contact with the surface of the exhaust pipe. And the vibration damping action is maintained. In the present embodiment, both ends of the damper 2 are directly welded to the exhaust pipe, but brackets formed in an annular shape are welded to both ends of the damper 2 in advance.
The damper 2 may be fixed to the exhaust pipe via this bracket. Further, in this embodiment, the damper 2 is fixed to the exhaust pipe by welding. However, in the case where brazing is used or a bracket is used, a bracket is attached not only to the damper but also to the exhaust pipe. You may rivet.

[0016]

According to the method for mounting the exhaust pipe damper of the present invention, a tubular damper formed by weaving a metal wire and having an inner diameter smaller than the outer diameter of the exhaust pipe is prepared. Since the steps of elastically expanding and fitting the exhaust pipe so as to cover the surface of the exhaust pipe and fixing the damper in a state where the damper is pressed against the surface of the exhaust pipe, the following effects can be obtained.

When the damper is temporarily elastically deformed to expand its inner diameter and this damper is fitted to the exhaust pipe, its elastic restoring force can be used as a pressing force against the exhaust pipe. Vibration energy is easily transmitted to the damper, and the vibration damping action can be enhanced. Also, even if the metal wire that composes the damper expands due to heat or vibration energy, the pressure applied to the surface of the exhaust pipe only slightly decreases, and the damper remains in close contact with the surface of the exhaust pipe. Therefore, loss of the vibration damping effect can be prevented, and radiation noise generated from the exhaust pipe can be reduced over a long period of time.

[Brief description of the drawings]

FIG. 1 is a front view showing a method of mounting an exhaust pipe damper according to an embodiment of the present invention.

FIG. 2 is a partially sectional front view showing a conventional method of mounting an exhaust pipe damper.

[Explanation of symbols]

2 damper d ₂ inside diameter

Claims (1)

(57) [Claims] 1. A damper formed by weaving a metal wire into a cylindrical shape having an inner diameter smaller than an outer diameter of an exhaust pipe,
A method for mounting an exhaust pipe damper, comprising: a step of elastically expanding the inner diameter of the damper to fit the exhaust pipe so as to cover the surface of the exhaust pipe; and a step of fixing the damper in a state of being pressed against the surface of the exhaust pipe. .