JP2004263765A - Dynamic damper - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a dynamic damper capable of reducing the cost without the need for rust prevention of a mass metal fitting. <P>SOLUTION: There are comprised of a pair of annular rubber elastic supports 1 and 1 which are axially attached to the outer perimeter of a rotating shaft at a distance, a cylindrical mass metal fitting 2 coaxially arranged outside the rotating shaft by supporting both shaft ends at a pair of the rubber elastic supports 1 and 1 at a distance, and a rubber coated layer 3 to coat the surface of the mass metal fitting 2 integrally formed with the rubber elastic supports 1 and 1 by vulcanizing with the mass metal fitting 2. The rubber coated layer 3 is vulcanized in the state that the mass metal fitting 2 is positioned at a positioning part where it is brought in contact with the inner perimeter of the mass metal fitting 2, so that the outer perimeter side of the mass metal fitting 2 is completely coated. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a dynamic damper that is attached to the outer periphery of a rotating shaft such as a drive shaft or a propeller shaft of an automobile, and suppresses harmful vibration generated on the rotating shaft.
[0002]
[Prior art]
Conventionally, dynamic dampers have been provided on rotating shafts such as drive shafts and propeller shafts of automobiles to reduce harmful vibrations that should not normally occur, such as bending vibrations and torsional vibrations caused by rotational imbalance during rotation. And various types are known, for example, as disclosed in Patent Documents 1 to 3. As such a dynamic damper, as disclosed in Patent Document 1 and the like, a pair of ring-shaped rubber elastic supports attached to an outer peripheral surface of a rotating shaft at a distance in an axial direction, and a pair of rubber elastic supports are provided. A cylindrical mass fitting which is coaxially arranged at a distance outside the rotary shaft with both shaft ends elastically supported by a support, and a rubber coating layer covering the surface of the mass fitting It has been known.
[0003]
The rubber covering layer and the rubber elastic support of the dynamic damper are integrally formed by vulcanization molding. That is, by inserting a mass metal fitting into a mold for vulcanizing and molding the rubber coating layer and the rubber elastic support, the rubber coating layer covering the surface of the mass metal fitting and the rubber elastic support are formed by vulcanization molding together with the mass metal fitting. The body is integrally formed of the same rubber material. At this time, the mass metal fitting arranged in the molding die is positioned so that the positioning portion protruding from the mold surface of the molding metal abuts on the outer peripheral portion of the mass metal fitting, and in that state, the rubber coating layer and the rubber elasticity are provided. The vulcanization molding of the support is performed.
[0004]
The dynamic damper manufactured in this manner is fitted to a predetermined portion of the outer peripheral surface of the rotary shaft such as a drive shaft, and is mounted by fixing the mounting portions of the pair of rubber elastic supports with a fixing band or the like. Can be When the harmful vibration is generated with the rotation of the rotating shaft, the harmful vibration is attenuated by the resonance of the mass metal fitting through the elastic deformation (mainly shearing deformation) of the rubber elastic support.
[0005]
[Patent Document 1]
JP 2001-280420A [Patent Document 2]
Japanese Patent Publication No. 7-47979 [Patent Document 3]
Japanese Utility Model Application Laid-open No. Hei 6-10642
[Problems to be solved by the invention]
By the way, in the above-mentioned conventional dynamic damper, when the rubber elastic support and the rubber coating layer are vulcanized and molded, the mass metal fitting is positioned by the positioning portion. No rubber coating layer is formed, and an exposed portion of the mass metal fitting is formed corresponding to the shape of the contact portion. If the exposed part of the mass fitting thus formed is exposed to the outside air, moisture adheres to the exposed part and rust is generated. As a result, the mass of the mass fitting is reduced and the dynamic damper is reduced. Causes a change in the characteristics. In particular, when a dynamic damper is used for a rotating shaft disposed near a road surface, such as a drive shaft of an automobile, rust is likely to be generated from the exposed portion because it is likely to receive rainwater or the like.
[0007]
Therefore, conventionally, when performing vulcanization molding of the rubber coating layer, an adhesive for bonding the formed rubber coating layer to the mass metal fitting is applied to the entire surface of the mass metal fitting, or the rubber coating layer is formed. After the formation, the rust prevention treatment such as applying a paint or the like to the exposed portion of the mass metal fitting has been dealt with. However, when such a rust preventive treatment is performed, productivity is reduced due to an increase in the number of manufacturing steps, and special equipment for the reduction is required. Therefore, a significant increase in cost cannot be avoided.
[0008]
The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a dynamic damper that does not require rust prevention treatment of a mass metal fitting and that can reduce the cost. .
[0009]
Means for Solving the Problems, Functions and Effects of the Invention
The invention according to claim 1, which solves the above-mentioned problem, comprises a pair of ring-shaped rubber elastic supports attached to the outer peripheral surface of the rotating shaft at an axial distance, and a pair of rubber elastic supports attached to the pair of rubber elastic supports. A cylindrical mass metal fitting that is elastically supported on the portion and is disposed coaxially at a distance outside the rotation shaft, and is formed integrally with the rubber elastic support body by being vulcanized together with the mass metal fitting. And a rubber coating layer covering the surface of the mass metal fitting, wherein the rubber coating layer is vulcanized in a state where the mass metal fitting is positioned by a positioning portion abutting on an inner peripheral portion of the mass metal fitting. Means is employed in which the molding is formed so as to completely cover the outer peripheral side of the mass metal fitting.
[0010]
In the dynamic damper of the present invention, when the rubber coating layer and the rubber elastic support are vulcanized and molded, the mass metal fitting inserted into the molding die is positioned by the positioning portion abutting on the inner peripheral portion of the mass metal fitting. It is vulcanized and molded in the state. At this time, since the positioning portion does not contact the outer peripheral portion of the mass metal fitting, the rubber coating layer formed so as to cover the surface of the mass metal fitting completely covers the outer peripheral side of the mass metal fitting. Formed. Therefore, the exposed portion of the mass metal fitting is not formed on the outer peripheral side of the mass metal fitting. In addition, an exposed portion of the mass metal fitting is formed at a portion where the positioning portion abuts on the inner peripheral portion of the mass metal fitting, but since this exposed portion is not exposed to the outside when the dynamic damper is attached to the rotating shaft. There is no danger of water or the like directly adhering, and it is not particularly necessary to perform rustproofing. Further, when the rubber coating layer is provided as in the present invention, the mass metal fitting itself does not rust, so that the mass metal fitting is exposed to the outside or the case where the rustproofing treatment is performed. The reliability against rust of metal fittings is improved.
[0011]
Therefore, according to the dynamic damper of the present invention, the cost reduction can be achieved without the need for the rust prevention treatment of the mass metal fitting.
[0012]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0013]
[Embodiment 1]
FIG. 1 is a cross-sectional view of the dynamic damper according to the present embodiment along the axial direction, and is a cross-sectional view of a portion corresponding to line II in FIG. 2, and FIG. 2 is a front view of the dynamic damper viewed from the axial direction. FIG.
[0014]
As shown in FIGS. 1 and 2, the dynamic damper of the present embodiment has a pair of rubber elastic supports 1, 1 formed in a ring shape, and a pair of rubber elastic supports 1, 1 with both shaft ends. An elastically supported cylindrical mass 2 and vulcanization molding together with the mass 2 are integrally formed with the rubber elastic supports 1 and 1 so as to completely cover the outer peripheral side of the mass 2. Rubber coating layer 3.
[0015]
The rubber elastic supports 1 and 1 are formed in a ring shape by vulcanizing and molding a rubber material such as natural rubber, and are constituted by a pair of members arranged symmetrically at a distance in the axial direction. . The rubber elastic supports 1, 1 are formed in a short cylindrical shape, and have mounting portions 11, 11 fitted on the outer peripheral surface of the rotating shaft, and have a diameter inward in the axial direction from one end of the mounting portions 11, 11. The support portions 12 and 12 extend obliquely outward in the direction.
[0016]
The mounting portions 11, 11 have an inner diameter slightly smaller than the outer diameter of the rotary shaft to which the dynamic damper is mounted, and are configured to press against the outer peripheral surface of the rotary shaft when mounted on the rotary shaft. Ring-shaped concave grooves 11a, 11a on which fixing bands (not shown) are mounted are provided on the outer peripheral surfaces of the mounting portions 11, 11, respectively. Further, the support portions 12, 12 are formed so as to become gradually thicker as they become distant from the attachment portions 11, 11, and are formed in a substantially hollow truncated cone shape.
[0017]
The mass metal fitting 2 is formed of a ferrous metal in a cylindrical shape having a predetermined mass. The two ends of the mass metal fitting 2 are elastically supported by a pair of rubber elastic supports 1 and 1 by fixing both ends of the shafts to the large-diameter end surfaces of the support portions 12 and 12. The mass metal fitting 2 has an inner diameter that is larger than the outer diameter of the rotating shaft by a predetermined dimension, and is coaxially arranged at a distance outside the rotating shaft when the dynamic damper is attached to the rotating shaft. Thereby, the mass metal fitting 2 can be displaced relative to the rotation axis in the radial direction through the elastic deformation of the support portions 12 and 12.
[0018]
The rubber coating layer 3 is integrally formed with the rubber elastic supports 1 and 1 by vulcanizing and molding a rubber material such as natural rubber together with the mass metal fitting 2 so as to cover the surface of the mass metal fitting 2. Is formed. That is, when the rubber coating layer 3 is vulcanized, as shown in FIG. 3, the mass metal fitting 2 is inserted into a mold for vulcanizing the rubber coating layer 3 and the rubber elastic supports 1 and 1. Then, the rubber coating layer 3 covering the surface of the mass metal fitting 2 and the rubber elastic supports 1 are integrally formed by vulcanization molding together with the mass metal fitting 2.
[0019]
The molding die 4 used here is composed of an upper die 41 and a lower die 42 that are divided into two in the vertical direction, and an upper core 43 and a lower die 42 that are formed in a substantially cylindrical shape and divided into two in the vertical direction (axial direction). And a core 44. A predetermined portion of the outer peripheral surface of the upper core 43 and the lower core 44 abuts on a corner where the inner peripheral surface of the mass metal fitting 2 inserted into the molding die 4 and the shaft end face intersect, thereby positioning the mass metal fitting 2. Positioning portions 43a and 44a are provided, respectively. The positioning portions 43a and 44a are provided at four locations at substantially equal intervals in the circumferential direction so as to position the mass metal fitting 2 in three axial directions, but are provided at three or more locations at substantially equal intervals. Position can be reliably determined.
[0020]
The mass metal fitting 2 inserted into the molding die 4 is arranged so that the axial direction thereof is the vertical direction, and vulcanization molding is performed in this state. Since the positioning portions 43a and 44a do not contact the outer peripheral portion of the mass metal fitting 2, the rubber coating layer 3 is formed to completely cover the outer peripheral side of the mass metal fitting 2. The rubber coating layer 3 is not formed on the inner peripheral portion of the mass metal fitting 2 where the positioning portions 43a and 44a abut, and the exposed portion 2a is formed corresponding to the shape of the abutting portion. 1 and FIG. 2).
[0021]
The dynamic damper of the present embodiment configured as described above is fitted to a predetermined portion of the outer peripheral surface of the rotation shaft such as a drive shaft, and the mounting portions 11 of the pair of rubber elastic supports 1 are recessed. It is attached by being fixed with a fixing band or the like wound around the grooves 11a. When the dynamic damper is attached in this manner, the exposed portion 2a formed on the inner peripheral side of the mass metal fitting 2 is not exposed to the outside, so that water or the like does not directly adhere. When the harmful vibration occurs with the rotation of the rotating shaft, the dynamic metal damper causes the mass metal fitting 2 to resonate through elastic deformation (mainly, shear deformation) of the rubber elastic supports 11, 11. By doing so, the harmful vibration is effectively attenuated.
[0022]
As described above, according to the dynamic damper of the present embodiment, the rubber coating layer 3 is vulcanized and formed in a state where the mass metal fitting 2 is positioned by the positioning portions 43a and 44a abutting on the inner peripheral portion of the mass metal fitting 2. Accordingly, since the outer peripheral side of the mass metal fitting 2 is completely covered, rust prevention treatment of the mass metal fitting 2 is not required, and the cost can be reduced.
[0023]
Further, since the mass metal fitting 2 itself is not rusted because it is covered with the rubber coating layer 3, the mass metal fitting 2 is not exposed when the mass metal fitting 2 is exposed to the outside or when a rustproofing process is performed. Can be improved with respect to rust.
[0024]
[Embodiment 2]
4 is a cross-sectional view of the dynamic damper according to the present embodiment along the axial direction, and is a cross-sectional view of a portion corresponding to the line IV-IV in FIG. 5, and FIG. 5 is a front view of the dynamic damper viewed from the axial direction. FIG.
[0025]
As shown in FIGS. 4 and 5, the dynamic damper of the present embodiment has a pair of rubber elastic supports 5, 5 formed in a ring shape, and a pair of rubber elastic supports 5, The elastically supported cylindrical mass metal member 6 and the rubber elastic support members 5 are integrally formed with the rubber elastic supports 5 by being vulcanized together with the mass metal member 6 so as to completely cover the outer peripheral side of the mass metal member 6. Rubber coating layer 7.
[0026]
The dynamic damper according to the present embodiment has the same basic configuration as the dynamic damper according to the first embodiment. When the rubber coating layer 7 and the rubber elastic supports 5 are formed by vulcanization molding, the dynamic damper according to the first embodiment is used. The only difference is that a different mold is used. Therefore, detailed description of the rubber elastic supports 5, 5, the metal fitting 6, and the rubber coating layer 7 will be omitted, and different points will be mainly described.
[0027]
As shown in FIG. 6, the forming die 8 used in the present embodiment is formed in a substantially cylindrical shape with an upper die 81 and a lower die 82 divided in a vertical direction, and arranged inside the mass metal fitting 6. It consists of one core 83. A corner portion where the inner peripheral surface of the mass metal fitting 6 to be inserted into the molding die 8 and one of the axial end surfaces intersect at a predetermined position on one axial end (lower die 82 side) of the outer peripheral surface of the core 83. Positioning portions 83a for abutting the positioning of the mass metal fittings 6 are provided at four locations at substantially equal intervals in the circumferential direction. The positioning portion 83a is elongated in the axial direction so that a portion abutting on the inner peripheral surface of the mass metal fitting 6 extends from one shaft end surface to the vicinity of the other shaft end surface. Accordingly, the positioning portion 44a provided on the other end side in the axial direction (the upper die 81 side) in the first embodiment is omitted, and the die can be removed without dividing the core 83 into two parts. .
[0028]
When the molding die 8 is used, the rubber coating layer 7 is not formed on the inner peripheral portion of the mass metal fitting 6 where the positioning portion 83a contacts, and the exposed portion 6a corresponds to the shape of the contact portion. Is formed (see FIGS. 4 and 5).
[0029]
In the dynamic damper of the present embodiment manufactured as described above, the rubber coating layer 7 is formed so as to completely cover the outer peripheral side of the mass metal fitting 6 as in the case of the first embodiment. The cost can be reduced without the need for the rust preventive treatment of No. 6. Further, since the mass metal fitting 6 itself is not rusted because it is covered with the rubber coating layer 7, the reliability of the mass metal fitting 6 against rust can be improved.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view taken along an axial direction of a dynamic damper according to a first embodiment of the present invention, and is a cross-sectional view of a portion corresponding to line II in FIG.
FIG. 2 is a front view of the dynamic damper according to the first embodiment of the present invention as viewed from an axial direction.
FIG. 3 is a cross-sectional view showing a state during vulcanization molding of the dynamic damper according to the first embodiment of the present invention.
4 is a cross-sectional view of a dynamic damper according to a second embodiment of the present invention along an axial direction, and is a cross-sectional view of a portion corresponding to line IV-IV in FIG.
FIG. 5 is a front view of a dynamic damper according to a second embodiment of the present invention as viewed from an axial direction.
FIG. 6 is a cross-sectional view showing a state during vulcanization molding of a dynamic damper according to Embodiment 2 of the present invention.
[Explanation of symbols]
1, 5 ... rubber elastic support 2, 6 ... mass metal fittings 3, 7 ... rubber coating layer 4, 8 ... molding die 11 ... mounting part 11a ... concave groove 12 ... support part 41, 81 ... upper die 42, 82 ... lower Mold 43 Upper core 44 Lower core 43a, 44a, 83a Positioning part 83 Core

Claims (1)

A pair of ring-shaped rubber elastic supports attached to the outer peripheral surface of the rotating shaft at a distance in the axial direction, and a pair of rubber elastic supports elastically supported at both shaft ends by the pair of rubber elastic supports; A cylindrical mass fitting coaxially disposed with a rubber coating layer formed integrally with the rubber elastic support by being vulcanized together with the mass fitting and covering the surface of the mass fitting; , A dynamic damper consisting of
The rubber coating layer is formed so as to completely cover the outer peripheral side of the mass metal fitting by being vulcanized and molded in a state where the mass metal fitting is positioned at a positioning portion abutting on the inner peripheral portion of the mass metal fitting. A dynamic damper characterized by:

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