JPS6129522Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a spring support structure for a vehicle.

As a conventional spring support structure for a vehicle, there is one shown in FIG. 1, for example. This is an example of a strut type front suspension in which a coil spring 1 and a shock absorber are installed on the same axis, and a cylinder tube (not shown in the figure), which forms a twin inch tube type shock absorber, is removably attached to the strut tube 3. Built-in. A piston (not shown) that divides the inside of the cylinder tube into an upper chamber and a lower chamber is loosely fitted into the cylinder tube, and the lower end of a piston rod 4 whose upper end projects outside the cylinder tube is fixed to this piston. There is. The lower end of the strut tube 3 is fixed to a steering knuckle 5 or the like.

Further, in the figure, 6 is a lower spring seat, and this lower spring seat 6 is fitted onto the outside of the strut tube 3 and fixed by welding. The coil spring 1 is compressed directly or via a rubber sheet or the like between an upper spring seat (not shown) externally fitted and fixed to the upper part of the piston rod 4. Furthermore, an inner cylinder (not shown) is fixed to the upper part of the atspa spring seat of the piston rod 4, and a mounting in is installed between the inner cylinder and the outer cylinder (not shown) fixed to the vehicle body with bolts and nuts. A simulator (not shown) is used. Thus, the upper end of the shock absorber to which the coil spring 1 is mounted is connected to the vehicle body side, which is the supported body, and the lower end of the shock absorber is connected to the road wheel side, which is the support body.

However, in such conventional vehicle spring support structures, the lower spring seat 6 on the supporting body side or the upper spring seat on the supported body side and the coil spring 1 are in direct contact with each other, or the coil spring 1 is in direct contact with the lower spring seat 6 on the supporting body side, or The structure was such that contact was made through the Therefore, not only when the lower spring seat 6 or the upper spring seat and the coil spring 1 are in direct contact with each other, but also when the two are brought into contact via a rubber sheet or the like, the rubber sheet or the like does not interfere with the coil spring 1. The two are in rigid contact through a rubber sheet, etc., which is compressed by the spring force and becomes hard, and which is actually extremely hard. Therefore, when the frequency of vibration input from the supporting body side or the supported body side matches the natural frequency of the coil spring 1, the coil spring 1 resonates, and this causes a rough vibration in the direction of expansion and contraction of the coil spring 1. A dense portion and a dense portion are formed and move in the same direction, causing a so-called surging phenomenon. As a result, an unreasonable force is applied locally to the coil spring 1, which not only impairs ride comfort, but also causes vibrations caused by the surging phenomenon to be transmitted to the passenger compartment, impairing the quietness of the passenger compartment. It was hot.

This invention was made by focusing on such conventional problems, and includes a disc spring interposed between at least one of the supporting body or the supported body and the coil spring, and this disc spring The purpose of this invention is to elastically connect the supporting body or the supported body and the coil spring by setting the amount of deflection when the vehicle is stationary to be approximately equal to the free height of the vehicle, thereby solving the above problem. .

This invention will be explained below based on the drawings.

2 and 3 show an embodiment of this invention, and are views of a strut type front suspension in which a coil spring 1 and a shock absorber are provided on the same axis.

First, to explain the structure, 3 in FIG. 2 is a strut tube.
Inside, a cylinder tube (not shown) forming a twin inch tube type shock absorber is removably housed. The cylinder tube is filled with hydraulic fluid, and a piston (not shown) that partitions the inside of the cylinder tube into an upper chamber and a lower chamber is loosely fitted therein. The piston is provided with an orifice (not shown) that communicates between the upper and lower chambers, and when the piston moves up and down within the cylinder tube, a damping force is obtained by the flow resistance of the hydraulic fluid that passes through the orifice. The lower end of a piston rod 4 whose upper end projects outside the cylinder tube is fixed to this piston. and,
A steering knuckle 5 is fixed to the lower end of the strut tube 3, and a load wheel (not shown) serving as a support is fixed to a spindle 5a of the steering knuckle 5.

An upper spring seat 7 is fixed to the upper part of the piston rod 4, and the upper part of the upper spring seat 7 of the piston rod 4 is also engaged with the piston rod 4 via a mounting insulator 8 that engages with the mounting insulator 8. It is connected to the vehicle body side plate 9. And strut tube 3
A coil spring 1 is interposed between the lower spring receiving portion 10 and the lower spring receiving portion 10 fitted onto the outside.

The lower spring receiving portion 10 includes a spring receiving member 11, a disc spring 12, and a disc spring receiving member 1, as shown in exploded enlarged views in FIGS. 3A to 3D.
3, and these members 11, 12, 13 are all ring-shaped. The disc spring receiving member 13 is
Its inner diameter is formed so that it can be fitted onto the strut tube 3, and an inner spring seat 13a on which the inner edge 12b of the disc spring 12 is fitted is formed on the outer periphery of one end surface.
form. Then, the disc spring receiving member 13 is externally fitted onto the strut tube 3 with the inner spring seat 13a facing upward, and these are fixed by welding or the like.

The disc spring 12 is formed such that there is a dimensional difference in the axial direction between the outer edge 12a and the inner edge 12b of one end surface.
has a free height h. And this disc spring 12
is preferably set so that the ratio (h/t) of the plate thickness t to the free height h is within the range of approximately 1.2 to 1.5, and furthermore, the spring force of the disc spring 12 is The amount of deflection of the coil spring 12 is set to be equal to the free height h and elastically deformed into a flat disk shape due to the load received from the coil spring 1 when the vehicle is stationary. With the concave surface of the disc spring 12 facing upward, the inner edge 12b is attached to the inner spring seat 1 of the disc spring receiving member 13.
3a, and the outer edge 1 of the disc spring 12.
2a is the outer spring seat 11 of the spring receiving member 11.
Fit a.

The outer spring seat 11a into which the outer edge 12a of the disc spring 12 is fitted is formed on one end surface of the spring receiving member 11, and the outer spring seat 11a is formed on the other end surface side.
A spiral spring seat 11b is formed on which one end of the coil spring 1 is seated. As shown in FIG. 2, each end of the coil spring 1 is seated between the spring seat 11b of the spring receiving member 11 and the upper spring seat 7. Then, the Atsupa spring seat 7 is fitted onto the piston rod 4 to cover the upper end of the coil spring 1, and the mounting insulator 8 and the vehicle body side plate 9 are then fitted over the Atsupa spring seat 7. Fits onto the top of the piston rod 4. And piston rod 4
By tightening the nut 14 screwed into the upper male thread, the coil spring 1 is held in a predetermined compressed state, and the upper spring seat 7, mounting insulator 8, and vehicle body side plate 9 are tightened and fixed.

Thus, the upper end of the shock absorber to which the coil spring 1 is mounted is connected to the vehicle body side, which is the supported body, and the lower end of the shock absorber is connected to the road wheel side, which is the support body.

Next, the action will be explained.

The spring constant of the disc spring 12 is determined by appropriately selecting the ratio (h/t) between the plate thickness t and the free height h (in this embodiment, h/t is within the range of 1.2 to 1.5). ), the characteristics shown by the broken line in FIG. 4 are obtained. That is, by bending the disc spring 12 in advance by the dimension of the free height h and elastically deforming it into a flat plate shape, the spring constant m of the disc spring 12 in this area becomes extremely small, and the spring constant m in this area becomes very small. As a boundary, the spring constant m of the disc spring 12 changes non-linearly in either direction of the amount of deflection. On this occasion,
The load n applied to the disc spring 12 has a characteristic as shown by the solid line in the figure, and as the amount of deflection of the disc spring 12 increases, the rate of increase in the load decreases, and the amount of deflection increases as the free height h When it becomes equal to , the rate of increase in load becomes zero, and when the amount of deflection is further increased beyond this point p, the load increases nonlinearly.

Thus, if the disc spring 12 is elastically deformed by the free height h in advance, it will be set at the point p where the rate of increase in the load becomes zero, so the spring constant of the disc spring 12 in this state is , will be extremely small. Therefore, the coil spring 1 and the lower spring receiving portion 10 are elastically connected while ensuring a certain amount of load transmission force (enough to support the weight of the vehicle). Therefore, vibrations are input from the road wheel side or the vehicle body side and are transmitted to the coil spring 1 or the lower spring receiving part 10, but high-frequency vibrations with a relatively small amplitude that are not attenuated by the coil spring 1 are , Belleville spring 12 with a small spring constant when set
absorbed and attenuated by

Figure 5 compares the vibration characteristics q of a conventional support device consisting of a single coil spring 1 and the vibration characteristics r of a support device according to the present invention that uses a disc spring 12 in combination with the coil spring 1 in terms of vibration transmission force. It is something. As shown in the figure, according to the present invention, it is possible to suppress the vibration input due to the surging phenomenon from being transmitted to the vehicle body, thereby improving the quietness in the vehicle interior.

Note that the disc spring 12 may be provided on both sides of the coil spring 1, and the disc spring 12 may have a shape such as a diaphragm spring used in a clutch device, which has a radially extending slit on the inner edge side. It may have a shape like this. In this case, the amount of deflection of the disc spring can be set larger than in the case of the above embodiment.

As explained above, in this invention, a disc spring is interposed between at least one of the support body or the supported body and the coil spring, and this disc spring is
The structure is such that the amount of deflection when the vehicle is stationary is set approximately equal to its free height. In this way, since the disc spring is elastically deformed in advance by the dimension of its free height, it is set at a point where the rate of increase in the load becomes zero.
The spring constant of the disc spring in this state is extremely small. Therefore, the coil spring and the supporting body or the supported body are elastically coupled while ensuring a load transmission force sufficient to support, for example, the weight of the vehicle. For this reason, vibrations are input from the road wheel side or the vehicle body side and are transmitted to the coil springs. However, high-frequency vibrations with relatively small amplitudes that are not attenuated by the coil springs are caused by It is absorbed and damped by the spring. Therefore, it is possible to suppress vibration input due to the surging phenomenon that occurs in the coil spring when vibration is input from being transmitted to the vehicle body, reducing noise inside the vehicle interior and improving its quietness. This effect can be obtained.

[Brief explanation of drawings]

FIG. 1 is a front view showing a conventional spring support structure, FIG. 2 is a front view showing an embodiment of this invention,
Figure 3A is a front view of the spring receiving member, Figure 3B
is a vertical cross-sectional view of A, and C is a vertical cross-sectional view of the disc spring.
FIG. 4 is a spring characteristic diagram of the disc spring, and FIG. 5 is a diagram showing the relationship between vibration frequency and transmitted force. 1...Coil spring, 3...Strut tube, 7...Atsupa spring seat, 8...
Mounting insulator, 9...Vehicle side plate, 10...Lower spring receiving part, 1
1... Spring receiving member, 12... Belleville spring, 1
2a...outer edge, 12b...inner edge, 13...disc spring receiving member, 13a...spring seat, 14...nut,
h...free height, q, r...vibration characteristics, t...plate thickness.

Claims (1)

[Claims for Utility Model Registration] (1) In a spring support device in which a coil spring is interposed between a support body and a supported body, and the supported body is supported by the support body, the support body or the supported body A spring support for a vehicle, characterized in that a disc spring is interposed between at least one of the coil springs and the disc spring has a deflection amount set to be approximately equal to its free height when the vehicle is stationary. structure. (2) The spring support structure for a vehicle according to claim 1, wherein the disc spring has a ratio of plate pressure to free height set to 1.2 to 1.5.