JPH0680043U - Dynamic damper - Google Patents

Abstract

(57) [Summary] [Purpose] To provide a dynamic damper capable of suppressing unintended vibration. A dynamic damper 1 of the present invention includes a mass body 2 having a plurality of through holes 21 whose axes are parallel to each other, and one end of which is fixed to a vibrating body (not shown) and which are located at the centers of the through holes 21 and are parallel to each other. A plurality of core members 3 and a plurality of rubber elastic bodies 4 integrally connecting the inner peripheral surface of each through hole 21 and the outer peripheral surface of the core member 3 located at the center of the through hole 21. There is. The dynamic damper 1 includes a plurality of core members 3
Therefore, the unintentional free vibration of the mass body such as the vibration around the core member 3 as the center of rotation is largely restricted, and the intended vibration can be efficiently damped.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a dynamic damper. This dynamic damper can be used as a damper for attenuating harmful vibrations in, for example, exhaust pipes and frames of automobiles.

[0002]

[Prior art]

 Conventionally, as a dynamic damper, as shown in FIG. 4, a cylindrical mass body 101 and a shaft hole 102 of the mass body 101 are coaxially disposed on the shaft center and fixed to a vibrating body such as an exhaust pipe. It is known that the shaft member 103 and the rubber elastic body 104 integrally connecting the outer peripheral surface of the shaft member 103 and the inner peripheral surface of the mass body member 101 are connected. The rubber elastic bodies 104 are arranged on both sides of the shaft member 103, and stopper rubbers 105 are provided above and below the shaft hole 102 with a space therebetween.

[0003]

[Problems to be solved by the device]

 Since the conventional dynamic damper has a high degree of freedom in the vibration direction of the mass body, it may resonate in a vibration direction other than the intended vibration direction and adversely affect vibration damping in the intended vibration direction. For example, the conventional dynamic damper shown in FIG. 4 aims to damp vibration in the axial direction and vibration in the direction perpendicular to the axis connecting both stoppers 105. However, in addition to the axial direction and the axis-perpendicular direction, vibrations in the rotation direction of the mass body 101, vibrations in the twisting direction, and the like may occur, and the original characteristics may not be sufficiently exhibited.

The present invention solves such a problem, and an object of the present invention is to provide a dynamic damper in which vibration other than vibration in an intended direction is unlikely to occur.

[0005]

[Means for Solving the Problems]

 The dynamic damper of the present invention comprises a mass body having a plurality of through holes whose axes are parallel to each other, a plurality of core members which are fixed at one end to the vibrating body, and which are located at the centers of the through holes and are parallel to each other, and the through holes. It comprises a plurality of rubber elastic bodies integrally connecting the inner peripheral surface of the hole and the outer peripheral surface of the core member located at the center of the through hole.

[0006]

[Action]

 The dynamic damper of the present invention has a plurality of core members and a plurality of rubber elastic bodies that are parallel to each other with respect to one mass body. With these multiple core members and multiple rubber elastic bodies, the degree of freedom of vibration of the mass body is greatly regulated, and the vibration is concentrated in the vibration in the intended direction and resonates with the vibration in the intended direction and attenuates the vibration. .

[0007]

【Example】

 Hereinafter, the dynamic damper of the present invention will be described together with an embodiment shown in FIGS. 1, 2 and 3. The dynamic damper 1 of the present embodiment includes a mass body 2, two core members 3, two rubber elastic bodies 4, four stopper rubbers 5, an intermediate cylinder 6 and a fall prevention plate 7. .

The mass body 2 is made of metal in the shape of a rectangular parallelepiped having a concave portion on the lower surface side. The mass body 2 has two through holes 21 penetrating from the upper surface side to the lower surface side. These through holes 21 are in plane symmetry with respect to the center plane passing through the center of the mass body 2 in the longitudinal direction. The core member 3 is composed of a metal pipe having a shaft hole 31. The intermediate cylinder 6 is formed of a thin metal pipe, and the lower end thereof extends in the centrifugal direction to form a flange 61.

The rubber elastic body 4 extends in the longitudinal direction of the mass body 2 around the core member 3 and integrally connects the outer peripheral surface of the core member 3 and the inner peripheral surface of the intermediate cylinder 6. Stoppers 5 are formed on the inner peripheral surface of the facing intermediate cylinder 6 at a predetermined interval in the width direction of the core member 3. A thin contact portion 41 made of rubber is also formed on the lower end surface of the flange 61 of the intermediate cylinder 6. The rubber elastic body 4, the stopper 5, and the contact portion 41 are integrally vulcanized by insert molding in which the core member 3 and the intermediate cylinder 6 are inserted. Then, the portion including the rubber elastic body 4, the stopper 5, the contact portion 41, the core member 3 and the intermediate cylinder 6 was press-fitted into the through hole 21 from the lower surface side of the mass body 2 and fixedly held in the through hole 21. It is a thing. The flange 61 of the intermediate cylinder 6 is fixed in contact with the bottom surface of the recess of the mass body 2.

The fall-out prevention plate 7 is formed of a metal plate having the same hole as the shaft hole 31 in a portion of the core member 3 located in the shaft hole 31. The fall prevention plate 7 is integrally fixed to the lower end surfaces of both core members 3 after the core member 3 is attached to the mass body 2. The dynamic damper 1 of this embodiment has the above-mentioned configuration. As shown in FIG. 3, the dynamic damper 1 is fixed to a bracket 8 fixed to an exhaust pipe (not shown) with bolts 81 and nuts 82. As a result, the two core members 3 are integrated with the exhaust pipe via the bracket 8, and the vibration of the exhaust pipe is transmitted to the core member 3 as it is. This vibration is transmitted to the mass body 2 via the rubber elastic body 4, and the mass body 2 resonates to dampen the vibration of the exhaust pipe.

In the dynamic damper 1 of this embodiment, the vibration parallel to the axial direction of the core member 3 and the vibration in the direction perpendicular to the paper surface in FIG. 3 are aimed to be damped. The rubber elastic body 4 undergoes shear deformation due to the vibration generated between the mass body 2 and the core member 3. In the dynamic damper 1 according to the present embodiment, since the two core members 3 are used, the rotational vibration centered on the core member 3 is suppressed. Therefore, the unintended vibration has less adverse effect on the intended vibration damping effect, and the vibration of the exhaust pipe can be damped more stably.

The contact portion 41 fixed on the flange 61 of the intermediate cylinder 6 prevents the flange portion 61 and the captive plate 7 from coming into direct contact with each other due to vibration, and prevents the generation of noise due to the contact between the metal members. In addition, the flange 61 and the fall prevention plate 7 are prevented from being damaged. The fall-off prevention plate 7 prevents the mass body 2 from falling off the core member 3 when the rubber elastic body 4 is broken due to deterioration or the like.

Although two core members are used in this embodiment, the number of core members is not limited to two, and it is also possible to use three core members or three or more core members. In addition, in the present embodiment, the core members and the rubber elastic bodies are arranged symmetrically with respect to the mass body with respect to the central cross section of the mass body. The arrangement of the core members and the rubber elastic bodies is not limited to the plane symmetry, and it is preferable that the core members and the rubber elastic bodies are arranged symmetrically with respect to the center of the mass body, the center plane, or the like. Furthermore, the fall prevention plate may be provided individually for the core member.

[0014]

[Effect of device]

 As described in detail above, the dynamic damper of the present invention suppresses unintended vibrations, so that the desired vibration damping is achieved more reliably.

[Brief description of drawings]

FIG. 1 is a plan view of a dynamic damper of this embodiment.

FIG. 2 is a cross-sectional view of a dynamic damper of this embodiment.

FIG. 3 is a cross-sectional view showing a usage state of the dynamic damper of the present embodiment.

FIG. 4 is a plan view of a conventional dynamic damper.

[Explanation of symbols]

1 ... Dynamic damper 2 ... Mass body
3 ... Core member 4 ... Rubber elastic body 5 ... Stopper
6 ... Intermediate tube 7 ... Fall prevention plate

Claims (1)

[Scope of utility model registration request] 1. A mass body having a plurality of through-holes whose axes are parallel to each other, a plurality of core members each having one end fixed to a vibrating body and located at the center of each of the through-holes and parallel to each other, and a plurality of the through-holes. A dynamic damper comprising a plurality of rubber elastic bodies integrally connecting an inner peripheral surface and an outer peripheral surface of the core member located at the center of the through hole.