JP2010031964A - Vehicular dynamic damper - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vehicular dynamic damper with reduced outer dimension when two masses different in resonance frequency are radially superposed with each other. <P>SOLUTION: The vehicular dynamic damper includes: a damper body 3 installed to a vibration control object 2; a mass 4 for high frequency disposed to an outer peripheral part of the damper body 3; and a mass 5 for low frequency disposed to the outside of the mass 4 for high frequency to be superposed in the axially orthogonal direction. The damper body 3 further includes: a shearing elastic part 3a elastically supporting an axially both end parts 4a of the mass 4 for high frequency in a shearing direction; and a compression elastic part 3b elastically supporting the mass 5 for low frequency in a compression direction. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a vehicle dynamic damper attached to a vibration suppression target member such as a drive shaft.

As this type of dynamic damper, for example, in Patent Document 1, a high-frequency vibration system mass is elastically supported via a first elastic support body protruding in a direction perpendicular to the axis on the outer peripheral portion of the damper main body, and the high-frequency vibration of the damper main body is There has been proposed a structure in which a low-frequency vibration system mass is elastically supported through a second elastic support body protruding in a direction perpendicular to the axis on the outer side of the system mass. According to this dynamic damper, vibration suppression effects in both the low frequency range and the high frequency range can be obtained with a single component.
JP 2007-315522 A

  By the way, the conventional dynamic damper employs a structure in which each mass is elastically supported by the first and second elastic supports projecting outward in the direction perpendicular to the axis on the outer peripheral portion of the damper main body. The diameter is increased, which is disadvantageous for securing a vehicle mounting space.

  The present invention has been made in view of the above-described conventional situation, and an object of the present invention is to provide a vehicle dynamic damper that can reduce the outer diameter while securing a vibration damping function in a plurality of frequency ranges.

  The present invention is a vehicle dynamic damper attached to a vibration suppression target member, a damper main body mounted on the vibration suppression target member, a high-frequency mass disposed on the outer periphery of the damper main body, A low-frequency mass disposed so as to overlap the axis perpendicular to the outside of the frequency mass, and the damper body includes a shear elastic portion that elastically supports both axial ends of the high-frequency mass in the shear direction; A compression elastic portion that elastically supports the low-frequency mass in the compression direction.

  According to the dynamic damper of the present invention, the damper main body includes a shear elastic portion that elastically supports both axial ends of the high frequency mass in the shear direction, and a low frequency mass disposed outside the high frequency mass. Since it has a compression elastic part that elastically supports in the compression direction, the outer dimensions can be reduced while securing the vibration control function in both the low frequency range and the high frequency range, and the vehicle mounting space can be reduced. It becomes easy to secure. In other words, the shear elastic part that supports both ends of the high-frequency mass has a smaller thickness dimension in the direction perpendicular to the axis than the compression type elastic part. The outer diameter can be reduced as compared with the case where they are stacked.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

  1 to 3 are views for explaining a vehicle dynamic damper according to an embodiment of the present invention. FIG. 1 is a sectional view of the dynamic damper (a sectional view taken along the line II in FIG. 2), and FIG. 3 is a side view of the dynamic damper as seen from FIG. 3, and FIG. 3 is a sectional view of the dynamic damper (a sectional view taken along line III-III in FIG. 1).

  In the figure, reference numeral 1 denotes a dynamic damper, which is attached to a drive shaft 2 as a vibration control target member. Although not shown, the drive shaft 2 transmits the rotational driving force from the engine to the left and right wheels.

  The dynamic damper 1 has an axial dimension of 74 mm and an outer diameter of about 72 mm. The damper main body 3 mounted on the drive shaft 2 and a high-frequency damper disposed on the outer periphery of the damper main body 3. It has a two-stage stacked structure comprising a mass 4 and a low-frequency mass 5 arranged so as to overlap the outside of the high-frequency mass 4 in the direction perpendicular to the axis.

  The high frequency mass 4 is made of metal formed in an annular shape, and is set to a mass corresponding to a resonance frequency of 500 to 700 Hz. The high frequency mass 4 is embedded in the axially central portion of the damper main body 3.

  The low frequency mass 5 is made of metal formed in an annular shape, and is set to a mass corresponding to a resonance frequency of about 110 Hz. The low-frequency mass 5 is arranged so as to be substantially coaxial with the high-frequency mass 4 and is set to about ½ of the axial length of the mass 4.

  The damper main body 3 is made of a substantially cylindrical rubber member, and an insertion hole 3c into which the drive shaft 2 is inserted is formed in the shaft core portion thereof. The insertion hole 3 c is formed to be slightly smaller in diameter than the outer diameter of the drive shaft 2, whereby the damper main body 3 is press-fitted into the drive shaft 2. Further, an engagement groove 3d to which a band member (not shown) is fastened is formed at one end of the damper main body 3 in the axial direction.

  A concave portion 3e having a diameter larger than that of the drive shaft 2 is formed at the axially central portion of the insertion hole 3c of the damper main body 3. Thus, a gap t that allows the high-frequency mass 4 to be displaced in the radial direction is provided between the damper main body 3 and the drive shaft 2.

  The damper main body 3 includes shear elastic portions 3a and 3a that elastically support both axial end portions 4a and 4a of the high frequency mass 4 in the shear direction, and a compression elastic portion that elastically supports the low frequency mass 5 in the compression direction. 3b.

  The shear elastic portion 3a is formed thick so as to integrally connect both end portions 4a of the high frequency mass 4 and the damper main body 3 in the circumferential direction. As a result, the shear elastic portion 3 a is elastically denatured in the radial direction with respect to the axis of the drive shaft 2 and absorbs the twist in the rotational direction of the drive shaft 2.

  The compression elastic portion 3b is integrally formed so as to protrude radially outward from an outer peripheral film 3f covering the outer peripheral surface of the high-frequency mass 4 of the damper main body 3.

  An annular portion 3g extending in the axial direction is formed on the outer peripheral surface of the compression elastic portion 3b, and a metal ring 6 is attached to the annular portion 3g. The low frequency mass 5 is fixed to the ring 6. As a result, the compression elastic portion 3 b is elastically deformed in a direction perpendicular to the axis of the drive shaft 2. The annular portion 3g and the outer peripheral film 3f are reinforced by a plurality of ribs 3h formed in the circumferential direction.

  The dynamic damper 1 is formed by integrally forming the damper main body 3, the high frequency mass 4 and the ring 6 by vulcanization, and then drawing the outer peripheral surface of the ring 6 so that the low frequency mass 5 is applied to the ring 6. Is manufactured by press-fitting.

  According to the dynamic damper 1 of the present embodiment, the damper main body 3 includes the shear elastic portion 3a that elastically supports the axial both ends 4a of the high-frequency mass 4 disposed on the outer peripheral portion thereof in the shear direction, Since it has the compression elastic part 3b which elastically supports the low frequency mass 5 arranged so as to overlap the outside of the frequency mass 4 in the compression direction, both the low frequency region and the high frequency region are controlled. While securing the function, the outer dimensions can be reduced, and the vehicle mounting space can be easily secured. That is, the shear elastic portion 3a that supports both end portions 4a of the high-frequency mass 4 has a smaller thickness dimension in the direction perpendicular to the axis than the protruding amount of the compression elastic portion 3b. The outer diameter dimension can be reduced as compared with the case where the portions are arranged in the radial direction. Incidentally, in this embodiment, it is possible to make the outer diameter smaller by about 6 mm than the conventional dynamic damper.

  Here, in order to further reduce the outer diameter, it is conceivable that both the high-frequency mass and the low-frequency mass are elastically supported by the shear elastic portion. However, if it does in this way, it is necessary to ensure sufficient clearance between both masses, and there exists a possibility that an outside diameter size may become large conversely. Further, when both are elastically supported by the shear elastic portion, it is difficult to make a difference in the resonance frequency range due to the structure, and a problem that a necessary vibration damping effect cannot be obtained arises.

  In the above-described embodiment, the drive shaft has been described as an example of the vibration suppression target member. However, the present invention is not limited to this, and can be applied to, for example, a propeller shaft or a steering shaft of a four-wheel drive vehicle. is there.

It is sectional drawing (II sectional view taken on the line of FIG. 2) of the dynamic damper for vehicles by one Embodiment of this invention. It is a side view of the dynamic damper. FIG. 3 is a sectional view of the dynamic damper (a sectional view taken along line III-III in FIG. 1).

Explanation of symbols

1 Dynamic damper 2 Drive shaft (Vibration control target member)
3 Damper body 3a Shear elastic part 3b Compression elastic part 4 Mass for high frequency 4a Both ends 5 Mass for low frequency

Claims (1)

A dynamic damper for a vehicle attached to a vibration suppression target member,
A damper body mounted on the vibration suppression target member;
A high frequency mass disposed on the outer periphery of the damper body;
A low-frequency mass disposed so as to overlap the outside of the high-frequency mass in the direction perpendicular to the axis;
The damper main body includes a shear elastic portion that elastically supports both axial end portions of the high-frequency mass in the shear direction,
A vehicular dynamic damper comprising: a compression elastic portion that elastically supports the low-frequency mass in a compression direction.

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