JP2001180316A - Center bearing support - Google Patents

Abstract

PROBLEM TO BE SOLVED: To effectively prevent a deterioration in characteristics resulting from resonance of a system having, as a spring, a bracket arm portion of a bracket. SOLUTION: An outer sleeve 11 secured to a vehicle body by way of a bracket 2 and an inner sleeve 12 disposed inside the outer sleeve 11 and fitted about a center bearing 3 are elastically coupled together via an elastic body 13. The outer sleeve 11 has a damper portion 14. The damper portion 14 consists of a mass member 141 and a spring portion 142 coupling the mass member 14 elastically to the outer sleeve 11. The spring portion 142 is part of the elastic body 13.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a center bearing support for elastically supporting a center bearing for rotatably supporting a propeller shaft of an automobile on a vehicle body side.

[0002]

2. Description of the Related Art A center bearing support is provided, for example, on a vehicle body side by elastically supporting a center bearing (ball bearing) mounted on the outer periphery of an axially intermediate portion of a propeller shaft of an automobile, so that a propeller shaft during traveling is provided. This reduces vibration transmission between the vehicle body side and the vehicle body side.

FIGS. 6 and 7 show a center bearing support 100 having a conventional structure. That is, in this type of center bearing support 100, the outer sleeve 101 and the inner sleeve 102 disposed on the inner periphery thereof are elastically connected via the elastic body 103 made of an elastomer having a cross-sectional shape bent in the axial direction. The outer sleeve 101 is fitted to a bracket ring portion 202a of a bracket 202 which is attached to the vehicle body 200 via a bolt 201, and the inner sleeve 102 is attached to an outer periphery of an axially intermediate portion of a propeller shaft 203. It is designed to be fitted to the outer race 204a of the center bearing 204 mounted on the surface.

[0004]

The center bearing support 100 having the above-mentioned conventional structure has a spring constant derived from the rigidity of the bracket arm portion 202b of the bracket 202 and the outer shape of the bracket ring portion 202a and the center bearing support 100 of the bracket 202. It has a natural frequency determined by the weight of the sleeve 101 and the elastic body 103. Therefore, when the vibration accompanying the rotation of the propeller shaft 203 reaches a predetermined frequency,
It is pointed out that resonance occurs in the direction indicated by the arrow V in FIG. 7 and the noise and vibration reduction characteristics deteriorate.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and a main technical problem thereof is to effectively prevent deterioration of characteristics due to resonance of a system having a bracket arm as a spring. It is in.

[0006]

The above technical problems can be effectively solved by the present invention. That is, the center bearing support according to the present invention includes an outer sleeve fixed to the vehicle body via a bracket, an inner sleeve disposed on the inner peripheral side of the outer sleeve and fitted on the outer periphery of the bearing, and the outer sleeve. An elastic body that elastically connects the inner sleeve,
A mass member and a damper portion including a spring portion for elastically connecting the mass member to the outer sleeve side.
The damper portion is set so that its natural frequency is substantially the same as the natural frequency of a system including the bracket, the outer sleeve and the elastic body, for example.

Further, in the present invention, it is more preferable that the spring portion of the damper portion is made of a part of an elastic body, or the damper portion is attached to the outer sleeve side by fitting.

[0008]

1 and 2 show a first embodiment of a center bearing support 1 according to the present invention. That is, the center bearing support 1 includes an outer sleeve 11, an inner sleeve 12 arranged on the inner periphery of the outer sleeve 11, and an elastic body 13 elastically connecting the outer sleeve 11 and the inner sleeve 12. , The outer sleeve 1
1 comprises a damper section 14 arranged on the inner periphery. The outer sleeve 11 is fixed to the vehicle body via the bracket 2, and the inner sleeve 12 is fitted to a center bearing 3 that rotatably supports a propeller shaft.

More specifically, the outer sleeve 11 and the inner sleeve 12 are made of metal, and both ends of the outer sleeve 11 are a vehicle body (not shown).
The inner sleeve 12 is fitted on the inner circumference of the bracket ring 22 of the bracket 2 composed of a bracket arm 21 fixed to the bracket 2 and a bracket ring 22 provided integrally at a longitudinally intermediate portion thereof. The bearing 3 is fitted to the outer race 31.

The elastic body 13 is formed of an elastomer material such as rubber, and its outer peripheral end 13a is
The inner peripheral end 13b is integrally vulcanized and bonded to the outer peripheral surface of the inner sleeve 12, and the both ends 13a and 13b are integrally vulcanized and bonded to the inner peripheral surface of the outer sleeve 11.
It has a cross-sectional shape bent in a substantially U-shape so as to be folded back in the axial direction between b.

The damper portion 14 includes a metal annular mass member 141 disposed on the inner peripheral side of the outer sleeve 11,
The mass member 141 includes a spring portion 142 that elastically connects to the inner peripheral surface of the outer sleeve 11. The spring portion 142 is formed by a part of the outer peripheral end 13 a of the elastic body 13 being interposed between the opposing peripheral surfaces of the outer sleeve 11 mass member 141 and vulcanized and bonded. .

The damper section 14 uses its natural frequency, which is determined by the mass of the mass member 141 and the spring constant of the spring section 142, of the bracket arm section 2 of the bracket 2.
1 and a natural frequency determined by the weight of the bracket ring portion 22 of the bracket 2, the outer sleeve 11 and the elastic body 13 of the center bearing support 1.

The center bearing 3 is basically a known one comprising an outer race 31 and an inner race 32 which are arranged concentrically with each other, and a number of steel balls 33 which are rotatably held at equal intervals in a circumferential direction therebetween. It consists of a ball bearing having a structure, and the steel balls 33 are lubricated with grease. As described above, the outer race 31 of the center bearing 3 is press-fitted to the inner sleeve 12 with an appropriate interference, and a propeller shaft (not shown) is rotatably supported on the inner periphery of the inner race 32. Things.

The center bearing support 1 having the above-described structure is, for example, when vibration is generated in the propeller shaft during running of an automobile, the inner sleeve 12 on the propeller shaft side and the outer sleeve 11 on the vehicle body side.
The elastic body 13 repeatedly bends and stretches with the relative eccentric movement of the elastic member 13 to effectively insulate the transmission of vibration to the vehicle body.

As described above, the bracket arm portion 21 and the bracket ring portion 22 of the bracket 2, the outer sleeve 11 and the elastic body 13 of the center bearing support 1 are combined with the spring constant of the bracket arm portion 21 and the bracket ring portion. A system having the mass 22, the outer sleeve 11, and the elastic body 13 is configured. For this reason, when the vibration accompanying the rotation of the propeller shaft reaches a predetermined frequency in a relatively high frequency range, a vibration indicated by an arrow V in FIG. 1 is generated in the system by resonance. It is effectively reduced by the damper part 14 in the support 1.

That is, since the same natural frequency as that of the system including the bracket arm 21, the bracket ring 22, the outer sleeve 11, and the elastic body 13 is set in the damper portion 14, the vibration caused by the resonance in the system. Is generated, the damper part 14 resonates with this, and the mass member 1
The dynamic vibration absorbing effect by the vibration direction of 41 being opposite to the direction of the input vibration V and the vibration damping effect by the internal friction of the spring portion 142 made of the elastomer are exhibited. Therefore, it is possible to prevent damage to the bracket 2 due to resonance, generation of noise, and deterioration of the vibration reduction characteristics of the center bearing support 1.

In the above-described embodiment, the mass member 141 of the damper portion 14 has a continuous annular shape. However, since the vibration V to be reduced occurs in the direction indicated by the arrow in FIG. As shown in FIGS. 3 and 4 according to the second embodiment of the present invention, the damper portion 14 is partially formed on the upper semicircle of the inner circumference of the outer sleeve 11 depending on the frequency, magnitude of the amplitude, and the like. May be provided only for

That is, in the second embodiment shown in FIGS. 3 and 4, the mass member 141 is formed in an arc shape having a circumferential end, and the mass member 141 is formed in the upper inner periphery of the outer sleeve 11. And between its opposing peripheral surfaces,
The spring part 142 which is a part of the elastic body 13 is vulcanized and bonded. The configuration of other parts is the same as in the first embodiment.

In the first and second embodiments, the spring portion 142 of the damper portion 14 is
When the elastic body 13 is vulcanized and bonded between the outer sleeve 11 and the inner sleeve 12, the damper portion 14 partially forms the mass member 141.
The outer sleeve 11 is formed by vulcanization bonding. Therefore, it can be easily manufactured without increasing the vulcanization step and the like.

Next, FIG. 5 shows a third embodiment of the center bearing support 1 according to the present invention. That is, in this embodiment, the outer sleeve 11 fixed to the inner periphery of the bracket ring portion 22 of the bracket 2, basically similar to the conventional center bearing,
An inner sleeve 12, which is disposed on the inner peripheral side of the outer sleeve 11 and is fitted on the outer periphery of the outer race 31 of the bearing 3, both ends 13a, 13b are vulcanized and bonded to the outer sleeve 11 and the inner sleeve 12,
An elastic body 13 made of an elastomer having a cross-sectional shape bent in a substantially U-shape so as to be folded back in the axial direction. A damper portion 14 is attached to the outer sleeve 11.

The damper portion 14 has a metal sleeve 143.
And a metallic annular mass member 141 disposed axially close to and opposed to a flange 143a formed at one axial end of the sleeve 143, and vulcanization between the flange 143a and the mass member. Spring portion 142 made of bonded elastomer
It is composed of The damper section 14 uses the natural frequency determined by the mass of the mass member 141 and the spring constant of the spring section 142 as a spring for the bracket arm section 21 (see FIG. 2 or FIG. 4) of the bracket 2 and a bracket ring section 22. , Outer sleeve 11 and elastic body 1
It is set to be substantially the same as the natural frequency of a system having 3 as a cell.

The outer sleeve 11 is formed such that its outer diameter is smaller than the inner diameter of the bracket ring portion 22 of the bracket 2, and the damper portion 14 is used when the center bearing support 1 is attached to the bracket 2. 143 is mounted by fitting it between the bracket ring portion 22 and the outer sleeve 11.

In this embodiment, the elastic body 1
A thick step 13c in the radial direction is formed at the bonding end of the inner sleeve 12 on the side of the inner sleeve 12, and the bonding end 13a with the inner peripheral surface of the outer sleeve 11 is also formed to be thick. Thus, when a large amplitude vibration is input between the vehicle body side and the propeller shaft, excessive relative displacement between the outer sleeve 11 and the inner sleeve 12 is restricted.

The center bearing support 1 having the above structure is also used for the inner sleeve 12 on the propeller shaft side and the outer sleeve 11 on the vehicle body side when the vehicle is running.
The elastic body 13 repeatedly bends and stretches in accordance with the relative eccentric movement of the elastic member 13 to effectively insulate the transmission of vibration to the vehicle body. Then, the vibration V due to resonance in a predetermined high frequency region of a system using the bracket arm portion 21 as a spring and the bracket ring portion 22, the outer sleeve 11, and the elastic body 13 as masses is transmitted to the first and second vibrations. Similarly to the embodiment, the dynamic damping effect and the damping effect due to the resonance of the damper portion 14 in the center bearing support 1 are effectively reduced.

The bracket arm 21, the bracket ring 22, the outer sleeve 11, and the elastic body 13
The frequency of the vibration V due to the resonance of the system composed of the above-described components differs depending on, for example, the shape, rigidity, and weight of the bracket 2. However, since the damper portion 14 is manufactured as a vulcanized molded product separate from the main body of the center pairing support 1 including the outer sleeve 11, the inner sleeve 12, and the elastic body 13, the specifications of the main body of the center bearing support 1, etc. By changing the mass of the mass member 141 in the damper section 14 and the spring constant and damping property of the spring section 142 without changing the frequency, the difference in the frequency of the vibration V can be easily handled. For this reason, it can be excellent in versatility.

As described above, when the center bearing support 1 is mounted, the damper portion 14
In the step of fixing the outer sleeve 11 to the bracket ring portion 22, the sleeve 143 may be fitted between the opposing peripheral surfaces of the outer sleeve 11 and the bracket ring portion 22 in a loosely fitted state, so that the outer sleeve 11 can be easily mounted. can do.

[0027]

As described above, according to the center bearing support of the present invention, since the outer sleeve is provided with the damper portion which exhibits a dynamic vibration absorbing effect by resonance at a predetermined frequency, the bracket arm is a spring. It is possible to disperse and reduce the peak of the system resonance, and effectively prevent the characteristic of the center bearing support from deteriorating due to the system resonance. Also, the spring portion of the damper portion can be easily manufactured by forming a part of the elastic body of the center bearing support body, and the damper portion can be manufactured as a separate body from the center bearing support body. This makes it possible to cope with a difference in the natural frequency (resonance frequency) of the system without impairing versatility.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a first embodiment of a center bearing support according to the present invention, cut along a plane passing through an axis O thereof.

FIG. 2 is a diagram viewed from a direction parallel to an axis in FIG. 1;

FIG. 3 is an explanatory view showing a second embodiment of the center bearing support according to the present invention by cutting along a plane passing through an axis O thereof.

FIG. 4 is a diagram viewed from a direction parallel to an axis in FIG. 3;

FIG. 5 is an explanatory view showing a third embodiment of a center bearing support according to the present invention by cutting along a plane passing through an axis O thereof.

FIG. 6 is a diagram showing a mounted state of a center bearing support according to the related art as viewed from a direction parallel to an axis thereof.

FIG. 7 is a side view showing a partial cross section of the mounted state of the center bearing support according to the related art, viewed from a direction perpendicular to the axis thereof.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Center bearing support 11 Outer sleeve 12 Inner sleeve 13 Elastic body 13a, 13b End part 14 Damper part 141 Mass member 142 Spring part 143 Sleeve 143a Collar part 2 Bracket 21 Bracket arm part 22 Bracket ring part 3 Center bearing 31 Outer race 32 Inner Race 33 steel ball

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Junichiro Yanagi 4-3-1 Tsujido Shinmachi, Fujisawa-shi, Kanagawa N.K.Megrastic Stock Company In-house F-term (reference) 3D042 AA06 AA08 AB01 DC02 DC04 DC05 DC08 3J012 AB07 BB03 DB08 DB13 FB10 GB01

Claims (3)

[Claims] An outer sleeve (11) fixed to a vehicle body via a bracket (2), and an inner sleeve disposed on the inner peripheral side of the outer sleeve (11) and fitted on the outer periphery of a bearing (3). Sleeve (1
2), the outer sleeve (11) and the inner sleeve (1).
And a spring member (142) for elastically connecting the mass member (141) and the mass member (141) to the outer sleeve (11) side. A center bearing support, comprising: 2. The center bearing support according to claim 1, wherein the spring part (142) of the damper part (14) comprises a part of the elastic body (13). 3. The center bearing support according to claim 1, wherein the damper part (14) is fitted to the outer sleeve (11) by fitting.