JP2003314271A - Supporting device for exhaust gas pipe - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a supporting device for an exhaust gas pipe which is miniaturized while securing a mass at a central vibration damper, and a clearance for a vertical displacement of a mass part. <P>SOLUTION: The supporting device is comprised of a first supporting part 2 at a vehicle side, a second supporting part 3 at an exhaust pipe side, a pair of side walls 4, 4 for connecting both the sides spacing therein, and a pair of connecting parts 62, 62 for connecting the mass 61 to the side wall 4 at both sides. Where the mass 61 is formed in mass larger than that of the connecting part 62, a width (W1) of the mass 61 is set two times or more the height (H1) of the mass 61. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a muffler hanger for an automobile, that is, an exhaust pipe support device for supporting an exhaust pipe on a vehicle body in a vibration-proof manner.

[0002]

2. Description of the Related Art Conventionally, as a supporting device for supporting an exhaust pipe on a vehicle body in a vibration-proof manner, it is integrally formed of an elastic material such as rubber and has a through hole into which a supporting material on the vehicle body side is inserted. The first holding portion and the second holding portion having the through hole into which the exhaust pipe side support member is inserted are mainly arranged so that the through holes of the two are parallel to each other and the left and right arches are opposed to each other with a vertical gap therebetween. It is known that they are connected to each other by both side wall portions and have a substantially annular shape as a whole.

This support device absorbs vibrations by an elastic material, but the side walls on the left and right are apt to swing due to vibrations on the vehicle body side or the exhaust pipe side, and in a high frequency region (for example, a region of 500 Hz or more). Since the dynamic absolute spring constant increases and it is not possible to expect a sufficient effect of suppressing vibration transmission, a central connecting part is arranged at an intermediate position between the first and second holding parts to connect the left and right side wall parts. It has been proposed (Japanese Patent Laid-Open No. 3-66953).

However, in the case where both side wall portions are simply connected by the central connecting portion as in this proposal, the rigidity in the left-right direction is increased and the lateral vibration is less likely to occur, so that the frequency range where the vibration transmission force is low is expanded. , For example 300-400H
In some cases, a sufficient effect of suppressing vibration transmission may not be obtained in z and the bands before and after z. Therefore, for the purpose of improving this, the applicant of the present invention has replaced the central connecting portion with a central portion having a mass portion having a larger mass than both side portions, and bilaterally branching the both side portions to form left and right side portions. A supporting device provided with a central damping portion connected to a wall is proposed (Japanese Patent Laid-Open No. 9-26438).
No. 1).

FIG. 8 shows a supporting device proposed by the applicant, in which (101) is a first holding part and (102) is a second holding part.
Retaining part, through holes (111) for inserting support materials
It has (112). Reference numerals (103) and (103) denote both side wall portions connecting the first and second holding portions (101) and (102),
Reference numeral (105) denotes a central damping section having the center as a mass section (105a). As shown in the figure, in the conventional central damping section (105), the width (w) of the mass section (105a) is set to be relatively narrow with respect to the height (h), which is effective in suppressing vibration transmission. Has a specific mass.

[0006]

By the way, in recent years, there has been a strong demand for weight reduction and compactness of vehicle parts, and there is also a demand for downsizing of this type of exhaust pipe supporting device. For example, the conventional vertical length is 65m
It is required to reduce the value of about m to about 50 mm.

However, if an attempt is made to reduce the size of the supporting device having the above-described central damping section,
It becomes difficult to secure a gap between the central mass part and the first and second holding parts above and below the mass part. That is, even if it is intended to make it compact, it does not necessarily mean that the conventional shape is directly reduced. While the distance between the first holding part and the second holding part becomes narrower, the central damping part operates in the same manner as in the conventional case, so that the mass of the mass part is secured at a certain level or more, and the upper and lower parts of the mass part are kept. It is also necessary to secure a clearance for directional displacement.

The present invention has been made in view of the above circumstances, and is compact while ensuring the mass of the mass part in the central damping part and ensuring the clearance for the vertical displacement of the mass part. It is an object of the present invention to provide an exhaust pipe support device that can be realized.

[0009]

An exhaust pipe support device according to the present invention is an exhaust pipe support device integrally formed of an elastic material such as rubber, and has a through hole into which a support member on the vehicle body side is inserted. A first holding part, a second holding part having a through hole into which a support material on the exhaust pipe side is inserted, and a pair of side wall parts that connect the first holding part and the second holding part on both sides thereof with a space therebetween. And a central damping portion arranged at an intermediate position between the first and second holding portions and connected to the both side wall portions, the central damping portion being formed as a mass portion. The center part and a pair of connecting parts that connect the mass part to the side wall part on both sides thereof have a mass larger than that of the connecting part, and the width (W1) of the mass part is the mass part. Part height (H1)
It is set to more than twice.

By making the mass part relatively flat in this way, the mass of the mass part is ensured even when the distance between the first holding part and the second holding part is narrowed due to the downsizing of the supporting device. However, the clearance above and below can be secured.

In the exhaust pipe supporting apparatus of the present invention, the dimension (T1) of the mass portion in the thickness direction of the supporting apparatus.
However, it may be set larger than the dimension (T0) of the side wall portion in the same thickness direction.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Exhaust pipe support devices according to embodiments of the present invention will be described below with reference to the drawings.

1 and 2 show an exhaust pipe support device (1) according to a first embodiment. This support device (1)
As shown in the figure, the overall shape of the main body is a substantially elliptical thick plate with the long axis in the vertical direction (z-axis direction) and the short axis in the width direction (x-axis direction). The elastic material, that is, the rubber material, is integrally formed in an annular shape when viewed from the front by vulcanization molding. The basic structure of this main body is as follows.

A first holding portion (2) having a through hole (21) in the thickness direction, into which a support member on the vehicle body side is inserted, is provided above the support device (1), and the first holding portion (2) is also provided. ) Has a second holding portion (3) having a through hole (31) in the thickness direction, into which the exhaust pipe side support member is inserted, at a lower portion facing each other at a required distance. Both the first and second holding parts (2)
(3) is connected by a pair of left and right arch-shaped side wall portions (4) and (4), both ends of which are connected to the left and right sides, respectively. Is formed in.

The side wall portions (4) and (4) are located between the two holding portions (2) and (3) at an intermediate position between the first and second holding portions (2) and (3). Some voids (5)
It is arranged so as to hold (5), and both ends are connected by the central damping section (6) connected to the inner surfaces of both side wall sections (4) and (4).

The central vibration control part (6) has a central part formed as a mass part (61) and left and right parts which support the mass part (61) on both sides thereof and are connected to both side wall parts (4) and (4). It consists of a pair of connecting parts (62) and (62), and the mass part (61) is the connecting part (62).
It has a larger mass than (62). Connection part (6
2) (62) is formed by bifurcating from the mass part (61) in the case of the figure, and the branch leg parts (63) (63), (6)
3) and (63) are respectively connected to the corresponding side wall portions (4) and (4).

The mass portion (61) is formed in a columnar shape which is flatter than in the conventional case, and the upper and lower first and second holding portions (2) are formed.
The width is set to be substantially the same as that of the inwardly extending portions (22) and (32) of (3). Specifically, the width (W1) of the mass part (61)
The ratio (W1 / H1) between the height and the height (H1) is set to be twice or more, whereby the distance (H2) between the first holding portion (2) and the second holding portion (3) is compared. Despite being narrow, the upper and lower clearances ((H2-H1) / 2) are secured while securing the mass of the mass part (61). The above ratio (W1 / H1) is more preferably 2 to 3 times, and in the case of the figure, W1 / H1 = 2.6 is set.

The height (H1) of the mass part (61) is 2 (thickness) of the connection part (62) in order to secure a large mass with respect to the connection parts (62) (62) on both sides thereof. It is preferable to set it to twice or more, and it is more preferable to set it to about 2.5 to 4 times. In addition, the width of the mass part (61) (W
1) is in the range of about 45 to 65% of the maximum gap (W2) between the left and right side wall parts (4) and (4) in order to secure a large mass for the connecting parts (62) (62) on both sides thereof. It is preferable that it is set within. Furthermore, the height of the mass part (61) (H
1) is within a range of about 45 to 65% of the gap (H2) between the first holding portion (2) and the second holding portion (3) in order to secure the above-mentioned mass and a clearance above and below it. It is preferable that it is set by.

As shown in FIG. 2, in this embodiment, the mass portion (6) in the thickness direction of the device (the front-back direction indicated by the y-axis direction, that is, the direction parallel to the axial direction of the through holes (21) (31)) is used.
1) and the size of the connection part (62) are set to the same value (T0) as the size of the side wall part (4) in the thickness direction,
Also, both the first and second holding portions (2) in the thickness direction.
The size of (3) is also set to the same value as the size of the side wall part (4). Therefore, in this supporting device (1), the dimension in the thickness direction is constant, and accordingly, the supporting device (1) is formed flat in the thickness direction.

3 and 4 show an exhaust pipe support device (11) according to a second embodiment of the present invention. In this embodiment, the mass portion (61) is provided with protrusions (64) (64) on both sides in the thickness direction. As a result, the mass portion (61) has a flat columnar shape extending in the thickness direction by the protrusion length of the protrusions (64) (64), and the dimension of the mass portion (61) in the thickness direction ( T1) is set larger than the dimension (T0) of the side wall portion (4) in the thickness direction. Further, as a result, the mass part (61) is
The mass is increased by the amount corresponding to the protrusions (64) (64). Since other configurations are similar to those of the first embodiment, the same reference numerals are given and description thereof is omitted.

In the supporting devices (1) and (11) of the respective embodiments configured as described above, the total length (H0) in the vertical direction and the maximum width (W0) in the width direction are not particularly limited, As an example, H0 is about 40-60 mm, W0 is 30-
It is preferably set to about 50 mm.

In the supporting devices (1) and (11), the supporting material on the vehicle body side is inserted and fixed in the through hole (21) of the upper first holding portion (2), and the lower second holding portion ( 3) Through hole (3
Support the exhaust pipe by inserting the support material on the exhaust pipe side into 1) and fixing it. In this usage state, the vibration transmitted from the exhaust pipe side and the vibration transmitted from the vehicle body side due to the operation of the engine are absorbed to prevent deterioration of noise vibration in the vehicle interior.

In the supporting devices (1) and (11) of this embodiment,
By making the mass part (61) of the central damping part (6) flatter than the conventional one, the space between the first holding part (2) and the second holding part (3) ( Even though H2) is narrower, the upper and lower clearances for the vertical displacement of the mass part (61) are secured while ensuring the mass of the mass part (61). The vibration transmission suppressing effect of the portion (6) is exerted.

A supporting device having such a central damping section is
Usually, it has three vibration modes, that is, the peak of the absolute spring constant. According to the analysis by the present inventors, these three vibration modes are caused by the following vibrations, respectively.

The first mode appearing at the lowest frequency side is, as shown in FIG. 5, the mass part (6) in the central damping part (6).
1) is a "mass", and the left and right connecting parts (62) (62) that support the mass part (61) on both sides are "springs", and the mass part (61) vibrates in the vertical direction. This is due to the resonance of the vibration having the vibration of the "mass-spring system" as the main element.

The second second mode appearing on the high frequency side of the first mode is bending vibration in which the mass portion (61) is regarded as a "beam" having both ends in the front-rear direction as free ends, as shown in FIG. This is due to the resonance of the vibration in which the vertical vibrations of the both side wall portions (4) (4) forming the ring are coupled.

The third mode on the highest frequency side is
This is due to resonance of vibration having bending vibrations of both side wall portions (4) and (4) forming an annular shape as a main element.

By the way, in the exhaust pipe support device,
Depending on the vehicle to be mounted, it may be required to reduce the absolute spring constant in a specific frequency range. In that case,
If the vibration mode exists in this specific frequency range and its vicinity, it is difficult to sufficiently satisfy this requirement by merely lowering the peak value of the absolute spring constant in the vibration mode. Therefore, it is desired to shift the resonance frequency of the vibration mode to separate it from the specific frequency range, thereby reducing the absolute spring constant in the specific frequency range.

With respect to this point, in the case of the supporting device (1) (11) having the central damping section (6) as described above, the resonance of the vibration mode is caused by adjusting the mass of the mass section (61) and the like. The frequency can be shifted in any direction on the low frequency side or the high frequency side, which can reduce the absolute spring constant in a specific frequency range.

For example, the vibration isolator (11) of the second embodiment.
Therefore, by providing the protrusions (64) (64) as masses on the front and back sides of the mass part (61), the resonance frequency of the first mode due to the vertical vibration of the mass part (61) can be reduced. It can be shifted to the frequency side. This is because, in the mass-spring system model such as the first mode, the resonance frequency decreases correspondingly as the mass increases. Further, since the length of the mass part (61) as a “beam” is increased by providing the protrusions (64) (64), the resonance frequency of the second mode caused by the bending vibration of the mass part (61). Can be shifted to the low frequency side. This is because, in bending vibration such as the second mode, the resonance frequency decreases correspondingly as the length of the “beam” increases.

In order to confirm this, the supporting device (1) of the first embodiment and the supporting device (11) of the second embodiment.
For and, the relationship between the frequency and the dynamic absolute spring constant was measured. In both supporting devices (1) and (11), the vertical total length (H0) is 50 mm and the width total length (W0) is 4 mm.
2 mm, the dimension (T0) in the thickness direction is 25 mm,
Rubber hardness of material (Japanese Industrial Standard Rubber Hardness Test Method (JI
The measurement method specified in S A) was A53. Further, in the supporting device (11) of the second embodiment, the dimension (T1) in the thickness direction of the mass part (61) is 30 mm.

The dynamic absolute spring constant was measured using a dynamic characteristic measuring and testing machine (KC-V type) manufactured by Sagimiya Seisakusho Co., Ltd. by means of rod-shaped metal fittings inserted into the first holding portion and the second holding portion of the supporting device. It is fixed to a jig of a dynamic characteristic tester, a predetermined load (50 N) is statically applied, and a predetermined vibration (0.03
mm constant), and the dynamic load / dynamic displacement (deflection) when swept from 100 Hz to 800 Hz and its phase angle were measured, and the absolute spring constant was calculated by a predetermined calculation method.

As is apparent from FIG. 7, in the supporting device (1) of the first embodiment, the frequency is around 400 Hz and 780H.
There was a peak of the absolute spring constant near z, but this was the second
In the supporting device (11) of the above embodiment, they were deviated to the low frequency side up to around 370 Hz and around 690 Hz, respectively. Therefore, for example, when the mounting vehicle is required to reduce the absolute spring constant near 500 Hz, the provision of the protrusion (64) can meet this requirement.

[0034]

According to the exhaust pipe supporting apparatus of the present invention, the mass portion of the central vibration damping section has a relatively flat shape, so that the supporting apparatus can be made compact and the first holding section and the second holding section are formed. Even when the interval is narrow, the upper and lower clearances can be secured while securing the mass of the mass portion, and the vibration transmission suppressing effect of the central vibration damping portion can be effectively exhibited.

[Brief description of drawings]

FIG. 1 is a front view of an exhaust pipe support device according to a first embodiment of the present invention.

FIG. 2 is a vertical sectional view of the support device.

FIG. 3 is a front view of an exhaust pipe support device according to a second embodiment.

FIG. 4 is a vertical sectional view of the support device.

FIG. 5 is a schematic diagram of a mass-spring system model.

FIG. 6 is a schematic diagram of a bending vibration model of a beam.

FIG. 7 is a graph showing the relationship between frequency and dynamic absolute spring constant.

FIG. 8 is a front view of a conventional exhaust pipe support device.

[Explanation of symbols]

(1) (11) Exhaust pipe support device (2) First holding unit (21) Through hole (3) Second holding unit (31) Through hole (4) Side wall (6) Central damping unit (61) Mass part (62) Connection part (64) Protrusion

   ─────────────────────────────────────────────────── ─── Continued front page    F-term (reference) 3D038 BA01 BA02 BA13 BC23                 3G004 AA01 BA02 BA04 BA09 DA13                       DA21 EA03 FA08                 3J048 AA01 BA21 DA07 EA30

Claims (2)

[Claims] 1. An exhaust pipe support device integrally formed of an elastic material such as rubber, wherein a first holding portion having a through hole into which a vehicle body side support member is inserted and an exhaust pipe side support member are inserted. Second holding part having a through hole formed therein, the first holding part and the second holding part
A pair of side wall portions that connect the holding portion to both sides of the holding portion at a distance, and a central damping portion that is arranged at an intermediate position between the first and second holding portions and that is connected to the both side wall portions are provided. The central vibration damping portion includes a central portion formed as a mass portion and a pair of connecting portions that connect the mass portion to the side wall portion on both sides thereof, and the mass portion is more than the connecting portion. An exhaust pipe support device having a large mass and a width (W1) of the mass part set to be twice or more the height (H1) of the mass part. 2. The dimension (T1) of the mass portion in the thickness direction of the supporting device is set to be larger than the dimension (T0) of the side wall portion in the thickness direction of the supporting device. Exhaust pipe support device.