Dynamic damper

Abstract

To provide a dynamic damper that can improve assemblability and prevent a mass from coming off at low cost.SOLUTION: A dynamic damper 1 includes a fitting member 2, a mass 3, a rubber elastic body 4, and an anti-slip-off member 5. The fitting member 2 is fitted to a vibration-controlled member 10. The mass 3 has a rectangular parallelepiped shape. The rubber elastic body 4 is bonded to both end surfaces of the mass 3 and an inner surface 220 of the fitting member 2 that is opposite to the end surfaces. The anti-slip-off member 5 is installed to the mass 3 so as to project from the mass and is locked to the fitting member 2.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a dynamic damper to be attached to the vibration system of an automobile. [Background technology]

[0002] Examples of dynamic dampers that are attached to the vibration system (objective component of vibration damping) of an automobile include the dynamic dampers disclosed in Patent Documents 1 to 3. The mass of the dynamic damper is vulcanization bonded to a bracket attached to the object component of vibration damping via a rubber elastic body. The dynamic damper has the following structure that prevents the mass from falling off from its attachment location on the object component of vibration damping even if the rubber elastic body peels off from the bracket due to deterioration over time.

[0003] The dynamic damper in Patent Document 1 comprises a support plate with a convex cross section that is attached to a target component to be damped and supports a mass via a rubber elastic body. The mass is a casting, and comprises a main body block with a tapered surface with a convex portion formed on the side, and a protruding block that protrudes from the top surface of the main body block and is inserted into an opening in the top plate of the support plate. The rubber elastic body covers the entire main body block and the inner surface of the support plate, elastically connecting the main body block and the support plate.

[0004] The dynamic damper in Patent Document 2 includes a mounting member welded to the target component and a gate-shaped member with a convex cross section that is attached to the upper wall of the mounting member and supports a mass member via a supporting rubber elastic body. The mass member is also a casting, and includes a mass body and a protrusion that protrudes from the underside of the mass body and is inserted into an opening in the upper wall of the counter member. As with the dynamic damper in Patent Document 1, the supporting rubber elastic body covers the entire mass body and the inner surface of the gate-shaped member, elastically connecting the mass body and the gate-shaped member.

[0005] The dynamic damper in Patent Document 3 has a rectangular mass member supported by a rubber elastic body with a bracket having a U-shaped cross section that is attached to the component to be damped, and a flat T-shaped plate-like pin welded to the underside of the mass member and inserted into an insertion hole at the bottom of the bracket. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Patent No. 6615020 (paragraph 0030-0037,0052) [Patent Document 2] Patent No. 6823560 (paragraph 0032,0040,0042) [Patent Document 3] JP 2008-51217 A (paragraphs 0002-0005) Summary of the Invention [Problem to be solved by the invention]

[0007] The dynamic damper of Patent Document 1 requires the design of a mold for the mass fitting that takes into consideration the tapered surface with the convex portion of the main body block of the mass fitting and the undercut caused by the protruding block, resulting in high manufacturing costs for the mold. Also, a complex molding cavity is required for the rubber elastic body that covers the entire main body block as well as the inner surface of the support plate fitting, which increases the costs of the material and molding of the rubber elastic body.

[0008] In the dynamic damper of Patent Document 2, the gate-shaped member that supports the mass member via the supporting rubber elastic body is attached to a mounting member, and the mounting member is then welded and fixed to the target vibration-damping member, resulting in a large number of parts and assembly steps. Also, as with the dynamic damper of Patent Document 1, a complex molding cavity is required for the supporting rubber elastic body, which increases the costs of the material and molding of the supporting rubber elastic body.

[0009] The dynamic damper of Patent Document 3 requires that the pin be inserted into the insertion hole of the bracket and welded to the mass from between the bracket and the mass after the rubber elastic body has been vulcanized and bonded to the bracket and the mass, making assembly work complicated. Also, as described above, because the pin is welded to the mass after the rubber elastic body has been vulcanized and bonded to the bracket and the mass, the heat of the welding may burn the rubber elastic body, causing it to peel off from the bracket and the mass.

[0010] The present invention has been made in view of the above circumstances, and has as its object to provide a dynamic damper that can prevent the mass from falling off while improving assembly efficiency and at low cost. [Means for solving the problem]

[0011] Therefore, one aspect of the present invention comprises a mounting member that is attached to the vibration-damping target component, a rectangular mass, a rubber elastic body that is adhered to both end faces of the mass and the inner surface of the mounting member that faces these end faces, and a retaining member that protrudes from the mass and engages with the mounting member. [Effects of the Invention]

[0012] According to the present invention, a dynamic damper can be provided that can prevent the mass from falling off while improving assembly efficiency and at low cost. [Brief explanation of the drawings]

[0013] [Figure 1] FIG. 1A is a top view of a dynamic damper according to one embodiment of the present invention; FIG. 1B is a side view of the dynamic damper; and FIG. 1C is a bottom view of the dynamic damper. [Figure 2] (a) is a perspective view of the mass of the dynamic damper, (b) is a perspective view of the mounting member of the dynamic damper, and (c) is a perspective view of the retaining member of the dynamic damper. [Figure 3] FIG. 4 is a perspective view of a mass to which the retaining member is fixed. DETAILED DESCRIPTION OF THE INVENTION

[0014] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0015] A dynamic damper 1 according to one embodiment of the present invention shown in FIG. 1 is attached to a target component 10 to be damped, such as a suspension member of an automobile, and damps vibrations of the target component 10 .

[0016] As shown in Figures 1 and 2, the dynamic damper 1 has a mounting member 2 that is attached to a mounting surface 11 of the vibration-damping target component 10, a mass 3 that is elastically supported by a rubber elastic body 4 on the mounting member 2, and a retaining member 5 that protrudes from the mass 3 and engages with the mounting member 2.

[0017] The mounting member 2 is made of a metal plate bent into a convex cross-section and has a flat plate portion 21 and a pair of mounting portions 22 facing each other at both ends of the flat plate portion 21. The flat plate portion 21 is generally rectangular, with a rectangular opening 210 formed in its center, through which the retaining member 5 is inserted. The diameter of the opening 210 is set so as to ensure a gap between the opening 210 and the main body 52 of the retaining member 5, thereby appropriately restricting the movement of the retaining member 5 on the mass 3. The mounting portion 22 has an L-shaped cross-section and includes a bottom plate portion 221 fixed to the mounting surface 11 and a support portion 222 bent vertically from one end of the bottom plate portion 221 to horizontally support the flat plate portion 21. The bottom plate portion 221 has a fixing hole 223 formed therein, through which the male thread of a fixing bolt 23 threaded into the mounting surface 11 is inserted.

[0018] The mass 3 is a rectangular parallelepiped metal member formed by extrusion molding or casting. As shown in Figure 1(b), spaces S are secured between the mounting surface 11 of the mounting member 2 and the mass 3, and between the flat plate portion 21 and the mass 3, and the mass 3 is supported horizontally by the rubber elastic body 4 between the inner surface 220 of the mounting portion 22 that faces the flat plate portion 21.

[0019] The rubber elastic body 4 is vulcanization bonded to the center of both end faces 31 of the mass 3 and also to the center of the inner surface 220 of the mounting member 2 facing both end faces 31, thereby elastically connecting both end faces 31 of the mass 3 and the inner surface 220 of the mounting member 2.

[0020] The retaining member 5 is made of a metal plate bent into an L-shaped cross section and has a fixing portion 51 and a main body portion 52. The fixing portion 51 is fixed by welding to a portion of the surface 32 of the mass 3 facing the flat plate portion 21 of the mounting member 2, which corresponds to the opening 210 of the mounting member 2. The main body portion 52 is bent vertically from one end of the fixing portion 51 and inserted into the opening 210 of the mounting member 2. The protruding height H of the main body portion 52 is set to be greater than the difference between the inner surface height H1 of the mounting member 2 and the height H2 of the mass 3. Note that the retaining member 5 may be fixed to the mass 3 using a fastener such as a set screw instead of welding.

[0021] The assembly process of the dynamic damper 1 will be described with reference to FIGS.

[0022] First, the retaining member 5 is welded to the surface 32 of the mass 3 at a location corresponding to the opening 210 of the mounting member 2. Next, the main body 52 of the retaining member 5 is inserted into the opening 210 of the mounting member 2. Next, the rubber elastic body 4 is molded into a rectangular cross section and vulcanized and bonded to the center of both end surfaces 31 of the mass 3, as well as to the center of the inner surface 220 of the mounting member 2 that faces both end surfaces 31. The male thread portion of the fixing bolt 23 is then inserted into the fixing hole 223 of the mounting member 2 and screwed into the mounting surface 11 of the target component 10 to be vibration-damped. In this manner, the dynamic damper 1 is attached to the target component 10 to be vibration-damped.

[0023] The dynamic damper 1 described above attenuates vibrations of the target component 10. Even if the rubber elastic body 4 peels off from the end face of the mass 3 or the inner surface 220 of the mounting member 2 due to deterioration over time, the main body 52 of the retaining member 5 is inserted into and engaged with the opening 210 of the mounting member 2, preventing the mass 3 from falling off from the mounting member 2. In particular, by setting the protruding height H of the retaining member 5 to be greater than the difference between the inner surface height H1 of the mounting member 2 and the height H2 of the mass 3, the mass 3 can be prevented from falling off even more reliably.

[0024] Furthermore, since the mass 3 has a rectangular parallelepiped shape, the mass 3 can be easily formed without considering undercuts, and the manufacturing cost of the mass 3 is significantly reduced compared to conventional dynamic dampers (for example, Patent Document 1).

[0025] Furthermore, because the rubber elastic body 4 is bonded to both end faces 31 of the mass 3 and the inner surface 220 of the mounting member 2 facing these end faces 31, there is no need for a complex cavity to mold the rubber elastic body, as compared to conventional dynamic dampers (e.g., Patent Documents 1 and 2).This reduces the cost of the rubber elastic body material and molding costs.

[0026] The retaining member 5 is pre-welded to one surface 32 of the mass 3 and then inserted through the opening 210 of the mounting member 2, allowing the rubber elastic body 4 to be vulcanization-bonded to both end surfaces 31 of the mass 3 and the inner surface 220 of the mounting member 2. This eliminates the risk of the rubber elastic body 4 being damaged during the welding process in the assembly process of conventional dynamic dampers (e.g., Patent Document 3), improving the yield rate (productivity) of the dynamic damper and improving assembly ease compared to conventional dynamic dampers. Furthermore, by vulcanization-bonding the rubber elastic body 4 to the center of both end surfaces 31 of the mass 3 and the center of the inner surface 220 of the mounting member 2, the material cost of the rubber elastic body 4 is further significantly reduced. If the heat from welding the retaining member 5 does not cause deterioration of the rubber elastic body 4, the retaining member 5 may be welded to the mass 3 after the rubber elastic body 4 has been vulcanization-bonded to the mass 3 and the mounting member 2.

[0027] Furthermore, the structure of the dynamic damper 1 is simplified by the fact that the retaining member 5 is made of a plate material with an L-shaped cross section that is fixed to the mass 3, and the mounting member 2 is made of a plate material with a convex cross section that has an opening 210 through which the retaining member 5 is inserted. This further simplifies the manufacturing cost of the dynamic damper 1.

[0028] The dynamic damper according to the present invention is not limited to suspension members, but can also be applied to any member to be subjected to vibration damping, whether in an automobile or something other than an automobile. [Explanation of symbols]

[0029] 1. Dynamic Damper 2...Mounting member, 21...Flat plate portion, 210...Opening portion, 22...Mounting portion, 220...Inner surface, 221...Bottom plate portion, 222...Support portion, 223...Fixing hole, 23...Fixing bolt 3...mass, 31...both ends, 32...face 4...Rubber elastic body 5...prevention member, 51...fixing portion, 52...main body portion 10... vibration damping target member, 11... mounting surface

Claims

1. a mounting member to be attached to the vibration-damping target member; A rectangular parallelepiped grid, a rubber elastic body bonded to both end surfaces of the mass and to the inner surface of the mounting member opposite to the both end surfaces; a retaining member that protrudes from the mass and engages with the mounting member; A dynamic damper comprising:

2. 2. The dynamic damper according to claim 1, wherein the rubber elastic body is vulcanized and bonded to the both end surfaces and the central portion of the inner surface.

3. The retaining member is made of a plate material having an L-shaped cross section that is fixed to the mass, 2. The dynamic damper according to claim 1, wherein the mounting member is made of a plate material with a convex cross section and an opening formed therein through which the retaining member is inserted.

4. 2. The dynamic damper according to claim 1, wherein the protruding height of the retaining member is greater than the difference between the height of the inner surface of the mounting member and the height of the mass.

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