JP4351371B2 - Dynamic damper - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a dynamic damper that is attached to a vibration body such as a vehicle body and reduces vibrations in the vibration body.
[0002]
[Prior art]
For example, a dynamic damper having a natural frequency corresponding to a resonance frequency of the members is disposed on members constituting a vehicle body of a vehicle such as an automobile, and vibration generated by the engine of the vehicle is transmitted to the dynamic damper. Absorbed, reducing the vibration of the members, and reducing the vehicle noise. As this type of dynamic damper, for example, a connecting fitting formed in a pipe shape, a mass member as a mass body arranged on the outer peripheral side of the connecting fitting, and an outer peripheral surface and a mass member of the connecting fitting are respectively vulcanized. Some have a rubber elastic body that is fixed by bonding or the like and elastically connects the mass member to the connection fitting.
[0003]
When attaching the dynamic damper as described above to the members of the vehicle body, for example, the bolt shaft erected on the members is inserted through the hollow portion of the connecting bracket, and the protruding portion of the bolt shaft from the connecting bracket is inserted. The dynamic damper is fixed to the members by screwing the nut.
[0004]
[Problems to be solved by the invention]
However, the above-described operation of attaching the dynamic damper to the members has to be performed using a relatively large tool such as an electric wrench in an engine room that has almost no extra space. There is a problem that is not good. In addition, in the dynamic damper as described above, water accumulates in the hollow portion of the connection fitting when it is attached to the members, and rust is generated on the metal parts such as the connection fitting in the dynamic damper due to the influence of this water in the long term. It becomes easy to do. For this reason, in a vehicle, in order to prevent the rust generation | occurrence | production by the water in a dynamic damper, the rust prevention coating and the rust prevention process are needed for the metal component of a dynamic damper.
[0005]
In addition, the dynamic damper as described above deteriorates with time due to the influence of ozone or the like, and the rubber elastic body is repeatedly subjected to a load when vibration is input. There is a possibility that the connecting portion is broken. For this reason, in the conventional dynamic damper, for example, a measure such as connecting the mass member and the connection fitting with a wire is taken, and even if the connection portion between the connection fitting and the mass member in the rubber elastic body breaks, It was prevented from falling off the connecting bracket. However, if such a measure is taken, the number of parts of the dynamic damper increases.
[0006]
In consideration of the above facts, the present invention makes it possible to attach water to the vibrating body without increasing the number of parts of the dynamic damper, and to accumulate water even when used in an environment where water is easily applied. The purpose of the present invention is to provide a dynamic damper that can be prevented, and without dropping the number of parts of the dynamic damper, even if the connecting portion between the mass body and the connecting bracket in the elastic member is broken, the mass body is removed from the connecting bracket. An object of the present invention is to provide a dynamic damper that can prevent the above-described problem.
[0007]
[Means for Solving the Problems]
The dynamic damper according to the present invention is provided with a rod-shaped protrusion, and is formed into a base fitting fixed to the vibrating body and a substantially pipe shape, and the protrusion is press-fitted into the hollow portion to be connected and fixed to the base fitting. And the mass body disposed on the outer peripheral side of the coupling metal, the outer circumferential surface of the coupling metal and the mass body, and the mass body is elastically coupled to the outer circumferential surface of the coupling metal An elastic member made of rubber, and a rubber closing member that is formed integrally with the elastic member and that seals the tip opening opposite to the insertion side of the protrusion in the coupling fitting. .
[0008]
According to the dynamic damper having the above-described configuration, if the base metal fitting is fixed in advance at a predetermined position of the vibrating body, the connecting metal fitting can be connected via the base metal fitting by simply press-fitting the protruding portion of the base metal fitting into the hollow portion of the connecting metal fitting. Can be connected and fixed to the vibrating body, so that the mounting operation of the dynamic damper to the vibrating body is simplified as compared with a dynamic damper that is attached to the vibrating body by screwing work such as bolts or nuts.
[0009]
In addition, the dynamic damper having the above structure is attached to the vibrating body, and the opening (insertion opening) on the insertion side of the protrusion in the coupling metal is sealed by the protrusion, and the tip opening opposite to the insertion opening is a closing member. Therefore, even when used in an environment where water is easily applied, such as in an automobile engine room, water can be prevented from entering the hollow portion of the coupling fitting. As a result, rust does not occur in the periphery of the dynamic damper in the coupling metal, the base metal, and the vibrating body due to the influence of water accumulated in the coupling metal. Further, since the closing member is formed integrally with the elastic member, it is not necessary to provide the closing member as an independent component, and an increase in the number of parts due to the provision of the closing member can be prevented.
[0010]
Here, when press-fitting the protrusion of the base metal fitting into the hollow part of the connecting metal fitting, when the protrusion is press-fitted into the connecting metal fitting by shrinkage fitting using thermal shrinkage such as shrink fitting or cold fitting. It is also possible to reduce the pressure input (pressing force) required for the press and to increase the connection strength between the base fitting and the fitting after press fitting. Moreover, if the outer surface exposed to the exterior of a connection metal fitting and a mass body is coat | covered with a part of elastic member, rust generation | occurrence | production on the outer surface of a connection metal fitting and a mass body can be suppressed effectively.
[0011]
Further, in the dynamic damper having the above-described configuration, the covering portion that covers the outer surface of the mass body on the elastic member and the first harness portion that is joined to the closing member and the covering portion, respectively, are integrally provided. In this case, even when the connecting portion between the connecting bracket and the mass body in the elastic member that repeatedly receives a load during vibration input is broken, the mass body is connected to the connecting bracket by the first harness portion. Can be prevented from falling off the connecting bracket.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a dynamic damper according to an embodiment of the present invention will be described with reference to the drawings.
[0013]
(Configuration of the embodiment)
1 and 2 show a dynamic damper according to an embodiment of the present invention and an engine mount to which the dynamic damper is attached.
[0014]
First, the engine mount 11 will be described. The engine mount 11 is of a so-called bush type, and includes a bracket metal member 12 that is fixed onto a vehicle body of an automobile by welding, bolts, and the like, and a mount body 14 that is assembled to the bracket metal member 12.
[0015]
The mount body 14 includes a cylindrical outer cylinder 16, a small-diameter cylindrical inner cylinder 18 that is arranged in parallel in the hollow portion of the outer cylinder 16, an outer peripheral surface of the outer cylinder 16, and an inner cylinder 18. A rubber elastic body 20 arranged between the peripheral surface and the peripheral surface is provided. The elastic body 20 is vulcanized and bonded to the outer peripheral surface of the inner cylinder 18 and is press-fitted into the hollow portion of the outer cylinder 16 together with the inner cylinder 18. Elastic body 20 is formed in a substantially X-shape around the axial center S _M of the mount main body 14, a pair of pressure contact portions 22 extending toward the outer periphery along the radial direction about the axis S _M and A pair of stopper portions 24 are respectively formed. Here, the front end surfaces of the pair of pressure contact portions 22 are in pressure contact with the inner peripheral surface of the outer cylinder 16, respectively, and the front end surfaces of the pair of stopper portions 24 are opposed to the inner peripheral surface of the outer cylinder 16 with a predetermined clearance. ing.
[0016]
The bracket metal fitting 12 fixed on the vehicle body is formed by bending a metal plate such as a stainless steel plate into a U-shape. The bracket metal fitting 12 has a bottom plate portion 26 and both end portions in the axial direction of the bottom plate portion 26. Side plate portions 28 bent at right angles toward the upper side are formed. The pair of side plate portions 28 are substantially the same shape as each other, the opening 30 is formed in the central portion centered on the axis S _M. The opening 30 has a substantially U shape opened toward the upper end side of the side plate portion 28 when viewed from the axial direction, and a recess 32 is formed in the vicinity of the lower end portion thereof. On the other hand, on the end surface along the axial direction of the outer cylinder 16, a pair of positioning portions 34 respectively corresponding to the concave portions 32 in the side plate portion 28 are formed so as to protrude in the axial direction.
[0017]
When the mount body 14 is assembled to the bracket fitting 12, the mount body 14 is fitted between the pair of side plate portions 28 of the bracket fitting 12, and any one of the pair of positioning portions 34 on the end surface of the outer cylinder 16 is attached to the side plate portion. 28 is inserted into the recess 32. Thus, the mount main body 14 is positioned to a predetermined position in the rotational direction around the axial direction and the axis S _M. In addition, the outer cylinder 16 of the mount body 14 is fixed to the bracket fitting 12 by welding or the like as necessary.
[0018]
Next, the dynamic damper 10 according to this embodiment attached to the engine mount 11 described above will be described. As shown in FIG. 1, the dynamic damper 10 is provided with a base fitting 36 that is fixed on the outer peripheral surface of the outer cylinder 16 of the engine mount 11. The base metal fitting 36 is integrally provided with an elongated round bar-like projection 38 and a base 39 having a large-diameter disk shape with respect to the projection 38 at one end of the projection 38. Base unit 39, its lower surface is fixed by welding or the like to the outer peripheral surface top of the outer cylinder 16, is projected upward along the projection 38 in the radial direction around the axis S _M of the engine mount 11.
[0019]
As shown in FIG. 1, the dynamic damper 10 includes a pipe-shaped connecting metal 40 that is connected to the mount body 14 via a base metal 36. A cylindrical hollow portion 42 passes through the connecting fitting 40 along the axis _SD . As a result, the base end opening 44 and the front end opening 45 are opened at both ends in the axial direction of the connection fitting 40. Further, the hollow portion 42 of the connection fitting 40 has an inner diameter of an interference fit with respect to the outer diameter of the base fitting 36.
[0020]
In the dynamic damper 10, as shown in FIG. 1, a metal mass member 48, which is a mass body, is disposed on the outer peripheral side of the connection fitting 40. The mass member 48 is formed in an elongated rectangular parallelepiped shape along the axial center _SD of the connection fitting 40, and as shown in FIG. 2, a U-shape is formed from one side surface on the outer peripheral side to the other side surface on the opposite side. A slot portion 50 is formed. The slot portion 50 penetrates from the lower end surface to the upper end surface of the mass member 48, and the projection portion 38 of the connecting metal fitting 40 is inserted into the slot portion 50 from the lower end surface side of the mass member 48. The bottom portion of the slot portion 50 is a curved surface having a substantially constant radius of curvature centered on the axis _SD , and the thickness along the radial direction is between the bottom portion of the slot portion 50 and the outer peripheral surface of the projection portion 38. A substantially U-shaped gap is formed.
[0021]
A rubber elastic member 52 is disposed between the mass member 48 and the protrusion 38 of the connecting metal fitting 40 as shown in FIG. 1, and the elastic member 52 elastically connects the mass member 48 to the protrusion 38. is doing. The elastic member 52 is filled in a U-shaped gap between the slot portion 50 of the mass member 48 and the outer peripheral surface of the projection 38, and is vulcanized and bonded to the connection fitting 40 and the mass member 48, respectively. A thin-walled covering portion 56, 58 that covers the outer peripheral surface of the connection fitting 40 and the outer surface of the mass member 48 is integrally formed. For example, the elastic member 52 is molded by using the coupling metal 40 and the mass member 48 as a mold core, and at the same time as the molding, the coupling part 54 and the covering parts 56 and 58 of the elastic member 52 are connected to the coupling metal 40 and the mass member 48. Each is vulcanized and bonded.
[0022]
The connection fitting 40 to which the mass member 48 is connected by the elastic member 52 is connected and fixed to the base fitting 36 after the mount body 14 of the engine mount 11 is assembled to the bracket fitting 12. When the connection fitting 40 is connected and fixed to the base fitting 36, the protrusion 38 of the connection fitting 40 is press-fitted into the connection fitting 40 hollow portion 42 as shown in FIG. Thereby, the connecting metal fitting 40 is connected and fixed to the base metal fitting 36 so as to be displaced integrally (vibrated). Accordingly, the mass member 48 is elastically connected to the base metal fitting 36 by the elastic member 52.
[0023]
Here, when the protrusion 38 of the base metal fitting 36 is press-fitted into the hollow part 42 of the connection metal fitting 40, shrink fitting or the like that press-fitting the protrusion 38 into the hollow part 42 while the connection metal fitting 40 is heated and expanded, You may use the cold fitting which press-fits the projection part 38 in the hollow part 42, making the base metal fitting 36 cool and shrink. When a shrinkage fit using such heat shrinkage is used, compared with a press-fitting method that does not use a shrinkage fit, the pressure input required when press-fitting the protrusion 38 into the hollow portion 42 of the connecting fitting 40 ( Pressure) can be reduced, and the connection strength between the base metal fitting 36 and the connection metal fitting 40 after press-fitting can be increased.
[0024]
In the dynamic damper 10, as shown in FIG. 1, a rubber closing member 60 that seals the distal end opening 45 of the coupling fitting 40 is integrally formed with the elastic member 52. The closing member 60 is formed in a cylindrical shape having a diameter larger than the inner diameter of the hollow portion 42, and the closing member 60 extends from the upper end portion of the outer peripheral surface to the outer peripheral side, and the tip portion thereof is the covering portion 56 of the elastic member 52. A band-shaped harness portion 62 joined to the outer periphery is provided. The harness portion 62 is a portion corresponding to the runway of the mold cavity when the closing member 60 is integrally formed with the elastic member 52, and connects the closing member 60 to the connecting metal fitting 40.
[0025]
The closing member 60 is press-fitted into the hollow portion 42 from the base end opening 45 after the protruding portion 38 of the base metal fitting 36 is press-fitted into the hollow portion 42 of the connecting metal fitting 40, and the outer peripheral surface thereof is inserted into the hollow portion 42. Press contact is made to the peripheral surface over the entire circumference. As a result, an air chamber 43 is formed in the hollow portion 42 of the connection fitting 40 between the distal end surface of the protrusion 38 and the closing member 60. The air chamber 43 is hermetically sealed by the closing member 60 and the projecting portion 38. Even if the dynamic damper 10 is used in the engine room, the air chamber 43 has rust such as water and corrosive gas. Substances that generate water do not enter.
[0026]
Next, the operation of the dynamic damper 10 according to this embodiment will be described.
[0027]
When an automobile engine (not shown) is operated, vibration is generated from this engine and transmitted to the engine mount 11. Thereby, the vibration energy is absorbed by the internal friction of the elastic body 20, and the vibration transmitted to the vehicle body side via the mount body 14 and the bracket fitting 12 is attenuated. However, the vibrations that can be effectively damped by the engine mount 11 are limited to those in a specific frequency range, and the damping effect on the input vibrations decreases as the frequency of the input vibrations deviates from that frequency range.
[0028]
On the other hand, the dynamic damper 10 is configured with a vibration system in which the mass member 48 is a mass body, and this vibration system is configured so that a higher frequency than the natural frequency of the engine mount 11 is a resonance frequency. Therefore, when the frequency of the vibration transmitted from the engine to the engine mount 11 becomes high and the outer cylinder 16 vibrates, this vibration (high frequency vibration) is transmitted to the dynamic damper 10 while elastically deforming the elastic member 52 to the mass member 48. Resonates. At this time, when the outer cylinder 16 of the engine mount 11 vibrates along the vertical direction, the elastic member 52 of the dynamic damper 10 mainly undergoes shear deformation, and when the outer cylinder 16 vibrates along the horizontal direction, the elastic member of the dynamic damper 10 52 undergoes compression / tensile deformation. Therefore, in the dynamic damper 10, the resonance frequency with respect to the vibration along the vertical direction and the horizontal direction is adjusted by changing the thickness and cross-sectional area of the elastic member 52 and adjusting the rigidity along the shearing direction and the compression / tension direction. Each can be tuned.
[0029]
In the dynamic damper 10, when the mass member 48 resonates, the inertia force of the mass member 48 is transmitted as a reaction force to the outer cylinder 16 of the engine mount 11, and this inertial force is applied to the engine mount 11 as a control force that cancels the vibration of the outer cylinder 16. Works. As a result, high-frequency vibrations that cannot be effectively damped by the engine mount 11 can be effectively damped by the control force from the dynamic damper 10, so that vibrations in a wider frequency range than when the input vibration is damped by the engine mount 11 alone. Can be effectively attenuated.
[0030]
Further, according to the dynamic damper 10 according to the present embodiment, if the base metal fitting 36 is fixed in advance to the outer cylinder 16 of the engine mount 11 that is a vibrating body, the protruding portion 38 of the base metal fitting 36 is hollowed in the connecting metal fitting 40. Since the connecting fitting 40 can be connected and fixed to the outer cylinder 16 via the base fitting 36 simply by press-fitting into the portion 42, the dynamic damper is attached to the outer cylinder 16 by screwing work such as bolts or nuts. The operation of attaching the damper 10 to the outer cylinder 16 is simplified.
[0031]
Further, in the dynamic damper 10 of the present embodiment, the base end opening 44 of the coupling fitting 40 is sealed by the protrusion 38 and the tip opening 45 of the hollow portion 42 is closed while being attached to the outer cylinder 16 of the engine mount 11. Since it is sealed by the member 60, it is possible to prevent water from entering the hollow portion 42 of the connecting fitting 40 even when used in an automobile engine room where water or oil is easily applied. As a result, it is possible to prevent rust from being generated in the periphery of the dynamic damper 10, the engine mount 11, and the dynamic damper 10 in the vehicle body due to the influence of water accumulated in the connection fitting 40. Further, since the closing member 60 is integrally formed with the elastic member 52, it is not necessary to provide the closing member 60 as an independent component, and the number of parts of the dynamic damper 10 due to the provision of the closing member 60 is increased. Can be prevented.
[0032]
Further, in the dynamic damper 10 of the present embodiment, the outer peripheral surface of the coupling fitting 40 and the outer surface of the mass member 48 are respectively covered by the covering portions 56 and 58, so that even when used in the engine room of an automobile, Rust can be prevented from being generated on the outer peripheral surface of the connection fitting 40 and the outer surface of the mass member 48, and rust-proof coating and rust prevention processing on the connection fitting 40 and the mass member 48 can be omitted or simplified. Furthermore, in the dynamic damper 10, the connecting metal fitting 40 can be manufactured simply by cutting a metal pipe that is commercially available as a standard product so as to have a predetermined length, so that the manufacturing cost of the dynamic damper 10 can be reduced.
[0033]
(Modification of the embodiment)
3 and 4 show modifications of the dynamic damper according to the embodiment of the present invention.
[0034]
The dynamic damper 70 shown in FIG. 3 is different from the dynamic damper 10 shown in FIG. 1 in that the end of the belt-shaped harness portion 72 extending from the closing member 60 is joined to the covering portion 58 that covers the mass member 48. The reinforcing member 74 is inserted into the harness portion 72. The harness portion 72 is integrally formed with the elastic member 52 so as to extend from the upper end portion of the outer peripheral surface of the closing member 60 to the outer peripheral side and to join the tip end portion near the top portion of the covering portion 58. An elongated reinforcing member 74 is inserted in the harness portion 72 along the longitudinal direction. The reinforcing member 74 is made of, for example, a fiber having a high tensile strength, such as a metal fiber, a carbon fiber, a polyamide fiber, or the like, or a metal processed into a belt shape. One end portion of the reinforcing member 74 is fixed to the top surface of the mass member 48 by spot welding, screwing or the like, and the other end portion extends from the proximal end portion of the harness portion 72 and is embedded in the closing member 60. . Here, the harness portion 72 is insert-molded with the reinforcing member 74 as a mold core.
[0035]
According to the dynamic damper 70 shown in FIG. 3, the end of the belt-shaped harness portion 72 extending from the closing member 60 is joined to the covering portion 58 that covers the mass member 48, thereby connecting the elastic member 52. Even when the portion 54 receives a repeated load at the time of vibration input and breaks, the mass member 48 is connected to the connection fitting 40 by the harness portion 72, so that the mass member 48 can be prevented from falling off the connection fitting 40. . Further, since the reinforcing member 74 having an end portion fixed to the mass member 48 and the other end portion embedded in the closing member 60 is inserted into the harness portion 72, the tensile strength of the harness portion 72 can be sufficiently increased. Even when the connecting portion 54 is broken, the harness portion 72 can be prevented from being broken by the load from the mass member 48. In addition, since the harness portion 72 is integrally molded with the elastic member 52, it is not necessary to provide the harness portion 72 as an independent component in the same manner as the closing member 60, and the dynamic due to the provision of the harness portion 72 is eliminated. An increase in the number of parts of the damper 70 can also be prevented.
[0036]
On the other hand, the dynamic damper 80 shown in FIG. 4 is different from the dynamic damper 10 shown in FIG. 1 in that the tip of the belt-shaped harness portion 72 extending from the closing member 60 is covered with the covering portion 58 that covers the mass member 48. The harness part 82 extended from the lower end part vicinity of the coating | coated part 58 and the elastic member 52 is integrally provided, and the front-end | tip part of this harness part 82 is connected to the base metal fitting 36 at the point joined. is there. Here, the harness portion 72 extending from the closing member 60 has the same shape as that shown in FIG. 3, but the structure is different from that shown in FIG. 3 in that the reinforcing member 74 is not inserted. ing. An annular connecting ring 84 is formed on the distal end side of the harness portion 82 extending from the covering portion 58. The connecting ring 84 is put on the outer peripheral side of the protruding portion 38 so that the protruding portion 38 of the base metal fitting 36 is press-fitted into the hollow portion 42 of the connecting metal fitting 40 and at the same time the lower side of the connecting metal fitting 40 is positioned. Accordingly, the mass member 48 is elastically connected to the connection fitting 40 by the connection portion 54 of the elastic member 52, and is connected to the connection fitting 40 and the base fitting 36 by the two harness portions 72 and the harness portion 82, respectively. .
[0037]
Therefore, according to the dynamic damper 80 shown in FIG. 4, even when the connecting portion 54 of the elastic member 52 is broken by receiving a repeated load at the time of vibration input, the mass member 48 is connected to the connecting bracket 40 by the harness portion 72. And since it will be in the state connected with the base metal fitting 36 by the harness part 82, the drop-off | omission from the connection metal fitting 40 of the mass member 48 can be prevented. At this time, the load from the mass member 48 when the connecting portion 54 is broken as compared with the case where the mass member 48 is prevented from falling off by only one harness portion 72 as in the dynamic damper 70 shown in FIG. Is distributed to the two harness portions 72, 82, the breakage of the harness portions 72, 82 can be prevented even if the tensile strength per one of these harness portions 72, 82 is low. When the connecting portion 54 is broken, the upper end portion and the lower end portion of the mass member 48 are connected to the engine mount 11 side by the two harness portions 72 and 82, respectively. Therefore, the mass member 48 can be prevented from colliding with other parts such as the engine mount 11 and damaging the other parts.
[0038]
In the dynamic damper 80 shown in FIG. 4, a reinforcing member is not inserted in any of the harness portions 72 and 82. Of course, the reinforcing member 74 shown in FIG. You may make it insert the reinforcement member similar to. Further, the tip of the harness portion 82 is not necessarily connected to the base metal fitting 36, and may be connected to the vehicle body or a portion fixed to the vehicle body.
[0039]
【The invention's effect】
As described above, according to the dynamic damper of the present invention, water is accumulated inside even if it is used in an environment where the mounting work to the vibrating body is easy and water is easily applied without increasing the number of parts. Further, even when the connecting portion between the mass body and the connection fitting in the elastic member is broken, it is possible to prevent the mass body from falling off the connection fitting.
[Brief description of the drawings]
FIG. 1 is a side sectional view showing a configuration of a dynamic damper and an engine mount to which the dynamic damper is attached according to an embodiment of the present invention.
FIG. 2 is a plan view showing a configuration of a dynamic damper and an engine mount to which the dynamic damper is attached according to the embodiment of the present invention.
FIG. 3 is a side sectional view showing a first modification of the dynamic damper according to the embodiment of the present invention and the configuration of an engine mount to which the dynamic damper is attached.
FIG. 4 is a side sectional view showing a configuration of a second modification of the dynamic damper according to the embodiment of the present invention and an engine mount to which the dynamic damper is attached.
[Explanation of symbols]
10 Dynamic damper 11 Engine mount (vibrating body)
36 Base metal fitting 38 Protrusion part 40 Connecting metal fitting 42 Hollow part 44 Base end opening 45 Front end opening 48 Mass member (mass body)
52 elastic member 54 connecting portion (elastic member)
56 Covering part (elastic member)
58 Covering part (elastic member)
60 Dynamic damper 60 Closing member 70 Dynamic damper 72 Harness part (first harness part)
74 Reinforcing member 80 Dynamic damper 82 Harness part (second harness part)

Claims (4)

A base metal fitting provided with a rod-shaped protrusion and fixed to the vibrating body;
A connection fitting that is formed in a substantially pipe shape, and the protrusion is press-fitted into the hollow portion to be connected and fixed to the base fitting;
A mass body disposed on the outer peripheral side of the coupling metal;
An elastic member made of rubber fixed to the outer peripheral surface of the coupling metal and the mass body, and elastically coupling the mass body to the outer circumferential surface of the coupling metal;
A rubber closing member that is formed integrally with the elastic member, and that seals the tip opening opposite to the insertion side of the protrusion in the coupling fitting;
A dynamic damper characterized by comprising: The elastic member is integrally provided with a covering portion that covers the outer surface of the mass body and a first harness portion that is joined to the closing member and the covering portion, respectively. The dynamic damper according to claim 1. 3. The dynamic damper according to claim 2, wherein the first harness portion is formed by inserting reinforcing members having both ends along the longitudinal direction connected to the mass body and the closing member, respectively. 4. The dynamic according to claim 2, wherein the elastic member is integrally provided with a second harness portion extending from the covering portion and having a tip portion connected to the vibrating body. damper.

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