JPH0415531Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a shock absorber that dampens vibrations generated from a vibration source such as an engine, and in particular is provided in a vehicle body frame to damp vibrations generated from an engine or the like. The present invention relates to a damping device for a vehicle.

[Technical background of the invention and its problems] In general, when a vehicle is running or the engine is idling, relatively low frequency (30 to 200
Hz) muffled sound occurs. This muffled noise is caused by the vibrations of the engine proportional to the engine speed and the vibrations of the power transmission system and intake/exhaust system connected to it, which propagate to the frame made up of the side members and cross members, or to the body. This causes this to resonate, and further propagates into the passenger compartment as a muffled sound. Conventionally, such muffled noise generated in the vehicle interior has been pointed out as a problem, and methods of improving the rigidity of the vehicle body frame have been proposed as a countermeasure for the noise. However, this method requires more components than the existing vehicle body frame, which is uneconomical. In order to solve this problem, a mass body is provided at an appropriate position on the existing frame, and the mass body is used to suppress vibrations generated in the vehicle body frame.

However, the above mass body is provided as a rigid body on the cross member that constitutes the vehicle body frame, and vibration of the mass body alone is not allowed, so depending on the direction of vibration occurring in the vehicle body frame, the vibration damping effect may not be sufficient. It was not possible to perform properly and was causing problems.

[Purpose of the invention] The present invention was devised in view of the various problems mentioned above, and its purpose is to suppress the vibrations transmitted from the engine to the frame, and thereby reduce the muffled vibrations transmitted to the passenger compartment. An object of the present invention is to provide a damping device for a vehicle that suppresses sound as much as possible.

[Summary of the invention] In a vehicle in which a drain hole is provided in a pipe cross member for supporting the engine, a clamp fitting is attached to the cross member so as to surround it, and a clamp fitting is integrally attached to the inner surface of the clamp fitting. a protrusion that is formed and removably fits into the drain hole; an elastic body that extends radially outward from the outer surface of the clamp fitting; and an elastic body that is integrally attached to the tip of the elastic body. and a mass body provided therein.

By engaging the protrusion in the drain hole of the pipe cross member in this way, the clamp fitting can be easily installed and the clamp fitting can be prevented from rotating after installation. Therefore, the elastic body vibrates in all directions and consumes vibration energy, suppresses vibrations propagated to the vehicle frame and body, and reduces muffled noise in the vehicle interior.

[Embodiment of the invention] A preferred embodiment of the invention will be described in detail with reference to the accompanying drawings.

1 and 2 are schematic diagrams showing the position of the damping device of the vehicle according to the present invention.

As shown in FIG. 1, the vehicle body frame 1 is
Side members 2, 2 each having a U-shaped cross section and arranged in parallel with a predetermined interval are connected to each other by cross members 3, 4.
and an appropriate number of connecting members 6, 7 are strung together.

An engine 5 is arranged on the front side of this body frame 1, and the rear part of this engine 5 is located on the frame 1.
It is suspended on a rear cross member 4 spanning between the side members 2, 2, and its front part is
Similarly, it is suspended from a front cross member 3 that extends between the side members 2, 2. These front and rear cross members 3, 4 are
The engine 5 is supported on the frame 1 via the engine 4, and is configured to attenuate its vibrations.

In addition, in FIGS. 1 to 3, the front cross member 3 is composed of a cylindrical tube portion 3a having a cylindrical cross section, and a base portion 3b provided at both ends of the tube portion 3a and attached to the side members 2, 2. Pipe part 3a
A drainage hole 21 is provided.

Next, the configuration of the damping device 11 will be described.

As shown in FIGS. 3 and 4, the damping device 11 includes a clamp fitting 12 attached to the cross member 3 so as to surround it, and a clamp fitting 12 that is integrally formed on the inner surface of the clamp fitting 12. A protrusion 22 that removably fits into the drain hole 21
, an elastic body 13 extending radially outward from the outer surface of the clamp fitting 12 , and a mass body 14 integrally provided at the tip of the elastic body 13 .

The upper frame 15 of the clamp fitting 12 is made of a steel plate or the like, and has an anti-arc shape with both ends further bent, with a cutout hole 16 at one end and a locking hole at the other end. A hole 17 is provided. On the other hand, the lower frame 18 is formed in an anti-arc shape like the upper frame 15, and both ends thereof are bent, and one end is engaged with a notch hole 16 formed in the upper frame 15. A locking hole 20 that engages with a locking hole 17 formed in the upper frame 15 is provided at the other end. Further, the lower frame 18 is provided with a projection 22 having an outer diameter that projects radially inward and engages with the drain hole 21 at approximately the center of the inner surface thereof.

On the other hand, two elastic bodies 13, 13 formed in the same shape are provided at appropriate positions on the anti-arc-shaped outer circumferential surface of the upper frame 15 and spaced apart from each other by a predetermined distance. ing. A plate-shaped mass body 14 is spanned between the other ends 25 and 26 of these two elastic bodies 13 and 13, and is integrally formed.

The damping device 11 is configured as described above, and the upper frame 15 and the lower frame 18 are provided so as to surround the front cross member 3.
After engaging the protrusion 22 formed in the cross member 3 with the drain hole 21 of the cross member 3 and further engaging the locking part 19 formed in the upper frame 18, the upper frame 1
5. Locking holes 17 and 2 provided in the lower frame 18
0 is fixed to the front cross member 3 by bolts 27, flat washers 28, and nuts 29.

The effects of the present invention will be specifically described below.

In FIGS. 2 and 3, vibrations generated from the engine 5 are propagated to various parts of the body via the cross members 3, 4 and the vehicle body frame 1. When this vibration is propagated to the cross member 3, the damping device 11 attached thereto vibrates in a direction that suppresses this vibration. That is, the elastic body 13 and the mass body 14 formed on the upper frame 15 of the damping device 11
When receiving the engine vibration transmitted from the cross member 3, it vibrates in a phase opposite to this vibration. As a result, vibrations transmitted from the engine 5 to the cross member 3 are suppressed, and muffled noise transmitted to the vehicle interior via the frame 1 is reduced.

Moreover, since the elastic body 13 of this damping device 11 is a cantilever vibration system with one end fixed, it vibrates following changes in the vibration direction of the engine 5, and exerts its vibration damping function on the attached cross member 3. It turns out.

Figure 5 is a diagram showing a comparison between the present invention and a conventional example in which the mass body is a rigid body and is installed in a cross member, and the change in muffled sound (dB) is measured using the engine speed (rpm) as a parameter. In the figure, the scores a _r and a _L indicate the change in the muffled sound of the conventional example, and the solid lines b _r and b _L indicate the change in the muffled sound of the present invention. Additionally, a _r and b _r on the upper side of the diagram are measurements of the muffled sound on the right side of the driver's seat, and the muffled sound has been reduced by approximately 10 dB compared to the conventional example.

A _L and b _L on the lower side of the diagram are measurements of the muffled sound on the left side of the passenger seat, which has been improved by about 15 dB compared to the conventional example.

[Effects of the Invention] As described above, the present invention exhibits the following excellent effects.

The damping device can be easily installed on the pipe cross member, and the clamp fittings can be prevented from rotating after installation, reducing vibrations propagated to the vehicle frame and body, reducing muffled noise in the passenger compartment. can be reduced.

[Brief explanation of drawings]

Figure 1 is a schematic plan view of the vehicle body showing the mounting position of the damping device of the present invention, Figure 2 is a schematic side view of Figure 1, and Figure 3 is the damping device of the present invention attached to the cross member of the vehicle body frame. Fig. 4 is a diagram showing the attenuation device of the present invention, and Fig. 5 is a diagram showing the changes in the muffled sound propagated to the passenger compartment according to the engine rotation speed of the present invention and the conventional example. It is. In the figure, 1 is the frame, 2 is the side member, 3, 4
1 is a cross member, 11 is a damping device, 12 is a clamp fitting, 13 is an elastic body, and 14 is a mass body.

Claims (1)

[Scope of utility model registration request] In a vehicle in which a water drain hole is provided in a pipe cross member for supporting an engine, a clamp fitting is attached to the cross member so as to surround it, and the water drain hole is integrally formed on the inner surface of the clamp fitting. a protrusion that removably fits into the clamp; an elastic body extending radially outward from the outer surface of the clamp fitting; and a mass body integrally provided at the tip of the elastic body. A vehicle damping device characterized by comprising: