JPH07756Y2 - Mounting structure for dynamic damper - Google Patents

Description

TECHNICAL FIELD OF THE INVENTION The present invention relates to a structure for attaching a dynamic damper to a leaf spring used in a vehicle suspension system.

(Prior Art) While the vehicle is running, when the leaf spring supporting the axle housing resonates with the wind-up vibration transmitted from the axle housing, a so-called low-speed muffled noise is generated in the passenger compartment, which gives an occupant an uncomfortable feeling. A dynamic damper is attached to the leaf spring to prevent resonance.

As a structure for attaching the dynamic damper to the leaf spring, as shown in FIG. 5, the dynamic damper is formed by the weight 10 and the rubber 12, while the stay 14 adhered to the inside of the rubber 12 is attached by the rivet 16 to the second spring plate 18. There is something stuck to.

Another mounting structure is described in Japanese Utility Model Publication No. 56-149141. In this mounting structure, as shown in FIG. 6, a bolt hole 23b is provided in a pair of projecting pieces 23a (only one of which is shown in the drawing) of the interleaf 22 arranged between the spring plates.
Bolt holes 24b are provided in the connecting portion 24a of the additional mass attachment. Then, the connecting portion 24a is brought into close contact with the projecting piece 23a, the bolt is passed through both bolt holes, and the nut is tightened to attach the additional mass attaching tool to the interleaf.

(Problems to be solved by the invention) In the mounting structure shown in FIG. 5, since the second spring plate 18 has a hole, the rivet 16 is driven in, and the stay 14 is fixed,
The position of the rivet hole is unavoidable because of the strength of the second spring plate. However, the second spring plate 18 has an original function of forming a leaf spring in combination with the first spring plate 20 which is longer than the second spring plate 18. Due to this functional restriction, the length of the second spring plate 18 is reduced. Limited As a result, the end of the second spring plate 18 is formed by the eye connected to the vehicle body provided at one end of the first spring plate 20 and the central portion of the first spring plate 20 to which the axle housing is connected. It will be located closer to one eye than the middle of the distance.

When the wind-up vibration is applied to the leaf spring from the axle housing, the vibration of the mode having the nodes at the ends of the first spring plate 20 and the center thereof as the node appears most strongly. Therefore, the antinode of the vibration is in the middle of the distance from the eye of the first spring plate 20 to the central portion, but as described above, the end of the second spring plate 18, that is, the mounting position of the dynamic damper, is the antinode of the vibration. The effect of the dynamic damper will not be fully exerted because it will be displaced from the position of.

In the case of providing the interleaf 22 shown in FIG. 6, the interleaf 22 can be positioned so that the dynamic damper is located at the antinode of vibration and can be attached to the leaf spring, so that the above-mentioned problem is solved. . However, each protruding piece
23a is constrained by the connecting portion 24a of the additional mass attachment, and the deflection when the leaf spring moves in the B direction is limited, so that stress concentration occurs especially at the root C of the overhanging portion A,
This causes the strength of the interleaf to drop.

An object of the present invention is to provide a dynamic damper mounting structure which has a high degree of freedom in selecting a mounting location of the dynamic damper and can secure the strength of the interleaf.

(Means for Solving the Problems) The present invention has a structure in which a dynamic damper is attached to a laminated leaf spring composed of a plurality of spring plates, and a held part disposed between the spring plates and the held A pair of mounting portions projecting laterally beyond both side surfaces of the spring plate from a portion, and an interleaf having a plate thickness smaller than the spring plate, and a connecting portion between each mounting portion and the dynamic damper. A spacer disposed between the spacer and the spacer, the projection of the spacer being included in the projection of the mounting portion when the spacer and the mounting portion are projected on an imaginary plane parallel to the surface of the mounting portion. It is the size.

(Operation and effect) When the leaf spring moves to achieve the original function of the suspension, the extent to which the deflection of the interleaf is limited is substantially the same as the size of the projection of the spacer. Since it is smaller than the size of the spacer, the projection of the mounting portion can be bent at a portion protruding from the projection of the spacer. As a result, stress concentration on the mounting portion protruding from the holding portion of the interleaf, particularly the root thereof, can be relaxed, and the durability of the interleaf can be improved.

The dynamic damper is easily attached to the interleaf by connecting means such as bolts and nuts, and the interleaf is fixed by sandwiching the sandwiched portion between the spring plates, thus maximizing the effect of the dynamic damper. It is possible to place it in a position where it can be demonstrated,
Greatly prevents low-speed muffled noise.

(Embodiment) As shown in FIGS. 1 and 4, the mounting structure 30 mounts the dynamic damper 36 on the leaf spring 34 composed of a plurality of spring plates 32a, 32b. It includes a leaf 38 and a spacer 40.

In the embodiment shown in FIGS. 1 and 2, the dynamic damper 36 comprises a rubber 37a and an annular weight 37b.
A rubber 37a is bonded to the inner peripheral surface of b. A pair of brackets 42 are spaced apart, bolts 44 are threaded through the sleeve and bracket 42 located in the center of the rubber 37a, nuts 46 are screwed onto the bolts 44, and the dynamic damper 36 is supported by the brackets 42. There is.

The interleaf 38, as shown in FIGS. 1 and 3,
Formed by a plate material having a plate thickness smaller than the plate thickness of the spring plates 32a and 32b of the leaf spring 34, that is, a plate material such as spring steel that is thin enough not to substantially affect the spring constant of the leaf spring 34. To be done. The interleaf 38 includes a held portion 39a arranged between the spring plates 32a and 32b and the held portion 39a, and
A pair of mounting parts that project laterally beyond both sides of a and 32b
With 39b. Bolt holes 48 are opened in the mounting portion 39b.

The connecting portion 43 of the bracket 42 supporting the dynamic damper 36 is attached to the attaching portion 39b. Therefore, the mounting part
39b is formed in a size corresponding to the size of the connecting portion 43 of the bracket 42.

The spacer 40 is arranged between the mounting portion 39b of the interleaf 38 and the connecting portion 43 of the bracket 42. The spacer 40 is formed in such a size that the projection of the spacer 40 is included in the projection of the mounting portion 39b when the spacer 40 and the mounting portion 39b are projected on a virtual plane parallel to the surface of the mounting portion 39b. In other words, the spacer
When the spacer 40 contacts the mounting portion 39b, the spacer 40
It fits in 9b. In the embodiment shown in FIG. 3, the spacer 40 is a washer formed in an annular shape, and its diameter D
Is smaller than the width A of the connecting portion 43 and enters the mounting portion 39b.

A bolt that is welded or press-fitted into the connecting portion 43 of the bracket 42.
Pass 50 through the spacer 40 and the hole 48 of the mounting portion 39b, and
Place the washer 52 on the underside and screw the nut 54 onto the bolt 50 to attach the bracket 42 and thus the dynamic damper 36 to the interleaf 38.

The range in which the bending of the mounting portion 39b of the interleaf 38 is restricted in the mounting state without the spacer is determined by the size A of the connecting portion 43. On the other hand, in the present invention, the spacer 40 is interposed between the mounting portion 39b and the connecting portion 43,
Since the spacer 40 has a size that fits in the mounting portion 39b, the range in which the deflection of the interleaf 38 is limited is determined by the size of the projection of the spacer 40. As a result, the interleaf
It is possible to prevent the occurrence of stress concentration particularly at the root of the mounting portion of 38.

The interleaf 38 is positioned so that the dynamic damper 36 serves as an antinode of vibration. That is, as shown in FIG. 4, an eye 35a provided at one end of the leaf spring 34a.
The gripped portion 39a is positioned so that the dynamic damper 36 comes to a position equidistant from the central portion of the leaf spring 34 to which the axle housing 56 and the axle housing 56 are connected.
9a is sandwiched between spring plates 32a and 32b.

The leaf spring 34 is used by connecting one eye 35a to the vehicle body 60 via the shackle 58 and the other eye 35b to the vehicle body 60 via the bracket 62. When wind-up vibration is applied from the axle housing 56, the dynamic damper 36
Is located on the antinode of vibration, it effectively acts on vibration and prevents low-speed muffled noise.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of the mounting structure, FIG. 2 is a lateral sectional view, and FIG.
The figure is an exploded perspective view, FIG. 4 is a side view of a suspension device, FIGS. 5 and 6 show a conventional mounting structure, FIG. 5 is a sectional view, and FIG. 6 is a perspective view. 30: Mounting structure, 32a, 32b, 32c: Spring plate, 34: Stacked leaf spring,
36: Dynamic damper, 38: Interleaf, 39a: Held part, 39b: Mounting part, 40: Spacer, 42: Bracket.

Continuation of the front page (72) Ken Matsuda 1 Toyota-cho, Toyota city, Aichi prefecture Toyota Motor Co., Ltd. (72) Inventor Tetsuro Hayashi 1-cho, Toyota city, Aichi prefecture Toyota car company (72) devised Satoshi Chikada 21-1 Kawabata, Yatsuda-cho, Chiryu-shi, Aichi (72) Inventor Kenji Murase 5-1-1 Homigaoka, Toyota-shi, Aichi (56) References JP 59-9333 (JP, A) Actual development Sho 56-149141 (JP, U)

Claims (1)

[Scope of utility model registration request] 1. A structure in which a dynamic damper is attached to a laminated leaf spring composed of a plurality of spring plates, and a sandwiched portion disposed between the spring plates and both side surfaces of the spring plate from the sandwiched portion. An interleaf having a plate thickness smaller than the spring plate, and a pair of mounting portions projecting laterally beyond
A spacer disposed between each of the mounting parts and the connecting part of the dynamic damper, wherein the spacer projects the spacer and the mounting part onto an imaginary plane parallel to the surface of the mounting part; The mounting structure of the dynamic damper, wherein the projection of the spacer is included in the projection of the mounting portion.