JPH01240717A - Vibration damping device for automobile - Google Patents

Abstract

PURPOSE:To prevent transmission of vibration to a vehicle body by connecting a hanger rubber between the vehicle body and an exhaust pipe, and by attaching a weight to an expandable part of the hanger rubber. CONSTITUTION:A hanger rubber 14 is connected between a vehicle body 13 and an exhaust pipe 11. The hanger rubber 14 and a weight 15 attached to an expandable part of the hanger rubber 14 constitutes a dynamic damper D. Vibration transmitted to the exhaust pipe 11 to the vehicle body 13 is effectively damped by the dynamic damper D. Thereby it is possible to transmit the vibration to the vehicle.

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to improvements in vibration damping devices for motor vehicles.

(Prior Art) Conventionally, as shown in FIGS. 6 and 7, the vehicle body 1 and the exhaust pipe 3 of the engine 2 are connected by a hanger rubber 4, and a dynamic damper, that is, a weight 5 is attached to the exhaust pipe 3. A vibration damping device for an automobile has been proposed in which a plate spring 6 (elastic body) is fixed and the resonant vibration of the exhaust pipe 3 is suppressed and damped by the dynamic damper (see Japanese Utility Model Publication No. 47-33060). .

(Problem to be Solved by the Invention) However, with the above-mentioned conventional technology, it is necessary to fix a separate dynamic damper to the exhaust pipe itself, and the hardness of the hanger rubber cannot be set high, resulting in a large vibration amplitude of the exhaust pipe. However, there was a problem in that the reliability of the exhaust pipe's zicointo part decreased.

The present invention was made to solve the above-mentioned conventional problems, and aims to simplify the dynamic damper and improve the reliability of the exhaust pipe joint by using hanger rubber as the elastic body of the dynamic damper. That is.

(Means for Solving the Problems) Therefore, in the present invention, a vehicle body and an exhaust pipe are connected by a hanger rubber, a weight is attached to an extendable portion of the hanger rubber, and a dynamic damper is constituted by the hanger rubber and the weight. It is characterized by the presence of

(Operations and Effects of the Invention) Since the present invention configures a dynamic damper by attaching weights to the extendable portion of the hanger rubber that connects the vehicle body and the exhaust pipe, the hanger rubber is used as the elastic body of the dynamic damper. This eliminates the need for a separate dynamic damper.

In addition, the hanger rubber suppresses the vibration amplitude of the exhaust pipe, improving the reliability of the exhaust pipe joint, while the resonance vibration transmitted from the exhaust pipe to the vehicle body via the hanger rubber is composed of the hanger rubber and the weight. Since the vibration is effectively damped by the dynamic damper, transmission of vibration to the vehicle body is effectively prevented.

Furthermore, since the deflection of the exhaust pipe is suppressed, the exhaust pipe can be placed closer to the vehicle body, which is advantageous in terms of vehicle body layout.

(Embodiments) Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

As shown in FIG. 5, the exhaust pipe 11 of the engine 10 is connected in series by joint parts 11a, . . . , 12 are interposed, and the exhaust pipe 11 is connected to the vehicle body 13 via hanger rubbers (dynamic dampers 4) at appropriate locations A, .

As shown in detail in Figure 3, the above hanger rubber! 4 is formed of a flat thick rubber plate, and has a large circular part 14a in the center, and small semicircular parts 1 at the upper and lower positions of the large circular part 14a.
4b and I4c, and a lateral protrusion (extensible portion) +4d is provided at one side of the large circular portion 14a.

A weight (mass) 15 is attached by baking to the side protrusion +4d of the hanger rubber I4.

The small semicircular portions 14b and 14c of the hanger rubber 14 are provided with hook insertion holes 14e and 14f.

The hanger rubber 14 is connected to the exhaust pipe l! The hardness is set higher than conventional hanger rubber so as to suppress the swing width.

As shown in FIGS. 1 and 2, the hanger rubber 14
When viewed from the side of the vehicle body (see FIG. 1), the flat portion faces in the left-right direction of the vehicle body, and is a small semicircular portion 14b.

Car body so that weight 14c faces in the vertical direction of the car body and weight 15 faces in the rear direction of the car body! 3 and the exhaust pipe If, and is fixed to the vehicle body 13, the vehicle body side hook 16 is inserted into the hook insertion hole 14e of the small semicircular portion 14b from inside the vehicle body toward the outside, and is inserted into the head 16a. The extraction is stopped and the exhaust pipe 1
Bracket on 1! The exhaust stand side hook 17 fixed through the hook 8 is inserted into the hook insertion hole 14f of the small semicircular portion 14c from the outside of the vehicle body toward the inside, and is prevented from being removed by the head +7a.

The vehicle body side hook 16 and the exhaust pipe side hook 17 are slightly offset relative to each other by a predetermined distance i1P in the longitudinal direction of the vehicle body.

As a result, the vehicle body 13 and the exhaust pipe 11 are connected to the hanger rubber 14.
while the hanger rubber (elastic body) 14
The dynamic damper D is composed of the weight 15 and the weight 15.

With the above configuration, the lateral protrusion (expandable portion) 1 of the hanger rubber 14 that connects the vehicle body 13 and the exhaust pipe 11
Since the dynamic damper D is configured by attaching the weight 15 to 4d, the hanger rubber 4 can be used as the elastic body of the dynamic damper D, and unlike the conventional technology, a separate dynamic damper is provided in the exhaust pipe. There will be no need for it.

In addition, by setting the hardness of the hanger rubber 14 higher than that of the hanger rubber of the conventional technology, the hanger rubber 14
Since the swing width of the exhaust pipe 11 is greatly suppressed by itself, there is no deterioration in the sealing performance of the joint part 1[a of the exhaust pipe 11, and the reliability of the joint part 11a is improved.

Then, the exhaust pipe 2 is passed through the hanger rubber 14 to the vehicle body 1.
The resonance vibration transmitted to the vehicle body 3 is effectively attenuated by the dynamic damper D composed of the hanger rubber 14 and the weight 15, so that vibration transmission to the vehicle body is effectively prevented.
This suppresses the occurrence of muffled noise inside the car.

Further, the hanger rubber 14 is supported in the vertical direction by the vehicle body side hook 16 and the exhaust pipe side hook 17, and each hook 16
．． 17 is offset in the longitudinal direction of the vehicle body, when a load is applied in the vertical or horizontal direction, the cross section of the side protrusion 14d of the hanger rubber 14 changes from the circular cross section shown in FIG. 4(a) to that shown in FIG. The cross section changes to an ellipse as shown in (b).

At this time, since the section modulus of the elliptical cross section is larger than that of the circular cross section a (a<b), the elliptical cross section is less likely to break, and the hanger rubber 14 can be prevented from breaking.

Furthermore, the exhaust pipe It is made of hanger rubber 14 with high hardness.
By suppressing the vibration of the exhaust pipe 11 to the vehicle body I3,
It can be placed close to the vehicle, which is advantageous in terms of vehicle layout.

[Brief explanation of the drawing]

FIG. 1 is a side view of the vibration damping device according to the present invention, FIG. 2 is a plan view of FIG. 1, FIG. 3 is a perspective view of the hanger rubber, and FIG.
Figures (a) and 4(b) are explanatory diagrams showing cross-sectional changes of the hanger rubber, Figure 5 is a schematic side view of the exhaust pipe system of an automobile according to the present invention, and Figure 6 is a conventional exhaust pipe of an automobile. A schematic side view of the tubing system, FIG. 7 is a cross-sectional view of a conventional vibration damping device. 10...Engine, 11...Exhaust pipe, 11a...
Jiji point part, 13... Vehicle body, 14... Hanger rubber, 14d... Lateral protrusion part, 15... Weight, 1
6...Hook on the vehicle body side, 17...Hook on the exhaust pipe side, D...Dynamic damper. Patent applicant Mazda Motor Corporation

Claims (1)

[Claims] (1) A vibration damping device for an automobile, characterized in that a vehicle body and an exhaust pipe are connected by a hanger rubber, a weight is attached to an extendable portion of the hanger rubber, and a dynamic damper is constituted by the hanger rubber and the weight.