JPS5810026Y2 - Center bolt mounting structure for stacked leaf springs - Google Patents

Description

[Detailed explanation of the idea] The present invention relates to a center bolt mounting structure for stacked leaf springs.

In stacked leaf springs used in vehicle suspension systems,
Each spring plate has a through hole formed in the center in the longitudinal direction, and is tightened in the thickness direction via a center bolt inserted through the through hole.

In addition, a pad arranged on the negative side in the thickness direction and a seat arranged on the other side and connected to the axle are provided in the longitudinal center of the stacked leaf spring, and these pads and seats are connected via U bolts. By being connected, the stacked leaf springs are supported.

In this type of conventional device, the head of the center bolt is fitted into a recess formed in the seat for positioning when assembling the leaf spring into the vehicle. If the bolts are loosely tightened, or if they loosen while the vehicle is running, the seat and spring plate are likely to become misaligned relative to each other, for example when the vehicle is started or stopped, or when driving on rough roads. A large shearing stress is generated between the head and the shaft of the bolt, which may lead to an accident in which the center bolt breaks.

Conventionally, a so-called cup center is known in which each spring plate is provided with a recess and a protrusion that are located at the center in the longitudinal direction and fit into each other, but this method cannot prevent the spring plates from being misaligned with each other. However, it is not possible to prevent misalignment between the spring plate and the seat, and it is not possible to prevent the neck of the center bolt from breaking.

The present invention was developed under the above circumstances, and its purpose is to provide a center bolt mounting structure for stacked leaf springs that can prevent breakage of the center bolt and improve its durability. .

Hereinafter, the present invention will be explained with reference to the illustrated embodiments.

In FIG. 1, a plurality of spring plates 1, 2.3 (in the case of three in the figure) superimposed in the thickness direction are provided with through holes 4 formed in the central part in the longitudinal direction, and A concave portion 5 formed on one side and a convex portion 6 formed on the other side.
The recesses 5 and the convexes 6 that face each other are fitted into each other.

A washer 7 is disposed on one side of the spring plate 3 disposed at the bottom, and this washer 7 is formed with a convex portion 7a that fits into the concave portion 5 of the spring plate 1.・・・
A through hole 8 is formed concentrically and with the same diameter.

A center bolt 9 is inserted through these through holes 4 . . . , 8 .

The head 9a of the center bolt 9 is disposed on the washer 7 side, and a nut 10 is screwed into the threaded end portion 9b.

The head 9a is provided with an appropriate detent formed by width on two sides or other means.

Further, a seat 12 connected to the axle 11 is provided on one side of the spring plate 3 disposed at the bottom, that is, the washer 7 side, and a pad 13 is provided on the other side of the spring plate 1 disposed at the top. It is being

The seat 12 is formed with a recess 14 into which the washer 7 fits and a recess 15 into which the head 9a of the center bolt 9 fits.

The pad 13 is formed with a recess 16 in which the threaded portion 9b of the center bolt 9 and the nut 10 are accommodated.

Upol N7,1 passed over pad 13? (7) Each leg is suspended along both sides of the spring plate 1, 2.3 in the width direction,
A nut 18 is screwed onto the lower end portion which protrudes through a through hole (not shown) formed in the sheet 12.

In the device configured as described above, the seat 12 is connected to the axle 11 of the vehicle as in the conventional device, and the end of the spring plate 1 is connected to the vehicle body.

If the tightening force between the U-bolts 17, 17 and the nuts 18 is relaxed, the spring plate 3 and the seat 12
When an impact force in the longitudinal direction or the width direction acts on the spring plate 3 and the convex part 7a of the washer 7, the impact force mainly acts on the peripheral walls of the concave part 5 of the spring plate 3 and the convex part 7a of the washer 7, as well as , the outer peripheral wall of the washer 7 and the sheet 12
The impact force acting on the head 9aK of the center bolt 9 through the inner peripheral wall of the recess 15 is greatly reduced.

Therefore, if the center bolt 9 has the same dimensions as the conventional one, its life will be significantly extended, and if the same life is acceptable, it can be made smaller in diameter than the conventional one, which can contribute to cost reduction6ζ.

In addition, 1. By providing each of the recesses 5 and the projections 6, it is possible to alleviate stress concentration in the periphery of the hole 4, and these recesses 5 and the projections 6
By forming the spring plates 1 to 3 into an oval or oval shape, relative rotation of the spring plates 1 to 3 around the center bolt 9 can be prevented, making it possible to omit conventional clips and the like. .

It should be noted that the present invention is not limited to the above-mentioned embodiments. For example, as shown in FIG. 2, the recesses 5 and the projections 6 may be formed in the opposite direction to that in FIG.
In this case, the convex portion 6 may be formed only on one spring plate facing the washer 7, as shown in FIG.

Furthermore, it is also possible to leave the spring plates 1 to 3 and washers 7 shown in FIGS. 1 to 3 as they are, and to attach the center bolt and nut upside down.

In any of these cases, it is desirable that the recesses 5 formed in the spring plates 1 to 3 be formed on the tension side, and the protrusions 6 formed on the compression side.

Further, by integrally forming the center bolt 9 and the washer 77 as illustrated in FIGS. 4 and 5, durability can be further improved.

In such a case, the bolt 9 and washer 7 may be bonded to each other with an adhesive, or may be fixed by caulking or welding, or may be made of the same material. Good too.

When the nut 10 is used as a reference instead of the head 9a of the center bolt, the washer and the nut 10 may be integrally formed as illustrated in FIGS. 6 and 7.

As described above, the present invention interposes a washer between the head of the center bolt and the spring plate, or between the nut and the spring plate, and forms a convex portion on either the spring plate or the washer. At the same time, a recessed part is formed on the other side to fit into this convex part, and the washer is fitted into the recessed part provided in the sheet, so that the external force acting in the longitudinal direction or width direction of the spring plate is reduced. It is mainly caught by a washer.

Therefore, the radial load applied to the center bolt is significantly reduced, which can greatly contribute to improving the durability and downsizing of the center bolt.

Furthermore, if the center bolt or nut and washer are integrally formed, the above-mentioned young fruit production can be further improved.

[Brief explanation of drawings]

Fig. 1 is a cutaway side view showing one embodiment of the present invention, Figs. 2 and 3 are cutaway side views showing modifications of the main parts, and Figs. 4 and 5 are bolts formed integrally. 6 and 7 are side views illustrating an integrally formed nut and washer. 1.2.3...Spring plate, 4...Through hole,
5... Concave portion, 6... Convex portion, 7...
...Washer, 8...Through hole, 9...Center bolt, 9a...Head, 10...
Natsuto.

Claims (2)

[Scope of utility model registration request] (1) A plurality of spring plates having a through hole formed in the center in the longitudinal direction are tightened in the thickness direction by a center bolt and nut inserted into the through hole,
A washer is interposed between the head or nut of the center bolt and the spring plate, and a convex portion is formed on one of the spring plate and the washer, and a concave portion that fits into the convex portion is formed on the other. A structure for attaching a center bolt to a stacked leaf spring, characterized in that the sheet superimposed on the washer side is provided with a recess that fits into the washer, and the recess and the washer are fitted into each other. (2) Scope of Utility Model Registration Claim No. (1) in which the above-mentioned center bolt or nut and washer are integrally connected.
Center bolt mounting structure for stacked leaf springs as described in section.