JPH0245463Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a vibration damping device for an engine exhaust pipe.

[Prior Art] Conventionally, as shown in FIG. 7, an engine E mounted on a vehicle has an exhaust pipe 1 with a main muffler 2.
is connected to the vehicle body B through the stay 3A and hanger rubber 3B at appropriate locations.
It is suspended and supported.

By the way, the exhaust pipe 1 arranged in this way
may resonate vertically or horizontally (vehicle width) while the engine is operating.

Therefore, as shown by the chain line in Fig. 7, the exhaust pipe 1
It has been proposed to attach to the exhaust pipe 1 a vibration damping dynamic damper 4 consisting of a weight 4C connected via a stay 4A and a rubber member 4B as a bending elastic member.

[Problems that the invention aims to solve] However, with conventional engine exhaust pipe vibration damping devices like this, it is only possible to suppress lateral vibration and vertical vibration. If so, there is a problem that a plurality of dynamic dampers 4 must be attached to the exhaust pipe 1.

The present invention aims to solve these problems by making it possible to simultaneously suppress vertical and horizontal vibrations with a single dynamic damper.
The purpose of the present invention is to provide a vibration damping device for an engine exhaust pipe.

[Means for solving the problem] Therefore, the engine exhaust pipe vibration damping device of the present invention is elastically suspended from the vehicle body, and one end of the exhaust pipe is connected to the engine. A vibration damping device includes a dynamic damper comprising an elastic member disposed near the exhaust pipe and a weight attached to the exhaust pipe via the elastic member, the elastic member being disposed near the exhaust pipe. It is characterized by being arranged at an angle with respect to the center line along the longitudinal direction of the exhaust pipe.

[Function] In the engine exhaust pipe vibration damping device of the present invention described above, the elastic member constituting the dynamic damper is
Since it is arranged to be inclined with respect to the center line along the longitudinal direction of the exhaust pipe, it is possible to simultaneously suppress vertical vibration and horizontal vibration of the exhaust pipe.

[Embodiment] A vibration damping device for an engine exhaust pipe as an embodiment of the present invention will be explained below with reference to the drawings. Fig. 1 is a schematic diagram showing its general configuration, and Fig. 2 is a perspective view of its dynamic damper. , Figure 3 is a graph to explain the work, Figure 4 is the IV- of Figure 2.
5 and 6 are sectional views showing other examples of the bending elastic member corresponding to FIG. 4, and in FIGS. 1 to 6, the same reference numerals as in FIG. Similar parts are shown.

As shown in Figure 1, an engine E installed in an automobile (vehicle) has an exhaust pipe 1 with a main muffler 2.
is connected to the vehicle body B through the stay 3A and hanger rubber 3B at appropriate locations.
It is suspended and supported.

By the way, as shown in FIGS. 1 and 2, the stay 3A near the rear end of the tail pipe of the exhaust pipe 1 has a weight 4 connected to the stay 3A via a stay 40A and a rubber member 40B as a bending elastic member.
A vibration damping dynamic damper 40 made of 0C is attached.
0 is arranged in an oblique direction so that the central axis C of the rubber member 40B intersects both the up-down direction a and the left-right (vehicle width) direction b (direction perpendicular to the plane of the paper in FIG. 1). .

With the above configuration, vertical vibration (resonance) and horizontal vibration (resonance) are generated in the exhaust pipe 1 while the engine E is operating.
Even if this occurs, the dynamic damper 40
Since the rubber member 40B vibrates vertically and horizontally, the vertical and horizontal vibrations of the exhaust pipe 1 are suppressed at the same time.

In this way, by damping the vibration of the front pipe section (dangerous section) D of the exhaust pipe 1 by using the dynamic damper 40 with the rear end of the tail pipe,
The overall vibration of the exhaust pipe 1 can be sufficiently suppressed.

Note that, as shown by symbols A and B in FIG. 3, the vertical and horizontal vibrations usually have different resonant frequencies, so the rubber member 40B has different vertical and horizontal lengths as shown in FIG. It is set to . This allows the elastic coefficients (spring coefficients) in the vertical and horizontal directions to be changed.

Furthermore, for the same purpose, the cross-sectional shape of the rubber member 40B may be made into an elliptical shape as shown in FIG. 5, or the rubber member 40B may be made up of two parts as shown in FIG. It is also possible to change the elastic modulus in the direction.

Note that in front-engine rear-wheel drive vehicles (FR vehicles), the exhaust pipe 1 does not generate longitudinal vibrations, but in front-engine front-wheel drive vehicles (FF vehicles), the exhaust pipe 1 generates longitudinal vibrations. In this case, the dynamic damper 40 should be arranged diagonally so that the center line C of the rubber member 40B of the dynamic damper 40 intersects not only the vertical and horizontal directions but also the front-rear direction. will be carried out.

[Effects of the Invention] As detailed above, the engine exhaust pipe vibration damping device of the present invention provides the following effects and advantages.

(1) Since the elastic member is arranged at an angle with respect to the center line along the longitudinal direction of the exhaust pipe, the vibration in the direction along the center line of the exhaust pipe and the vibration in the direction crossing the same center line are absorbed by the elastic member. It can be effectively reduced with only a single vibration damping device consisting of a weight and a weight.

(2) Since the vibration damping device is installed near the end of the exhaust pipe on the side opposite to the engine, that is, in the area where vibration amplitude tends to be the largest, it is possible to reduce the vibration extremely effectively. .

[Brief explanation of the drawing]

1 to 6 show a vibration damping device for an engine exhaust pipe as an embodiment of the present invention, FIG. 1 is a schematic diagram showing its general structure, FIG. Figure 3 is a graph for explaining its action, Figure 4 is a sectional view taken along the line IV-IV in Figure 2, and Figures 5 and 6 show other examples of each bending elastic member, corresponding to Figure 4. FIG. 7 is a schematic diagram showing a schematic configuration of a conventional engine exhaust system. 1...Exhaust pipe, 2...Main muffler, 3A...
Stay, 3B... Hanger rubber, 40... Dynamic damper, 40A... Stay, 40B... Rubber member as bending elastic member, 40C... Weight, B
...Car body, E...Engine.

Claims (1)

[Scope of utility model registration request] an elastic member disposed near the other end of an exhaust pipe that is elastically suspended from the vehicle body and whose one end is connected to the engine; and an elastic member that is attached to the exhaust pipe via the elastic member. An engine exhaust vibration damping device equipped with a dynamic damper comprising a weight, the elastic member being arranged at an angle with respect to a center line along the longitudinal direction of the exhaust pipe. Pipe vibration damping device.