JPS62184909A - Suspension device for vehicle - Google Patents

Abstract

PURPOSE:To freely adjust damping force in a simple formation by arranging an elastic member between a damper and a body or an axle, and regulating an elastic deformation quantity of an elastic member in a regulating means adjustable of a regulating position. CONSTITUTION:Rubber 4 is attached to the end of a piston rod 3 of a damper 1 demonstrating damping force through a disk 6, and a extending side spring 10A and a pressing side spring 10B are arranged. A stopper 13 is fixed at the end of the piston rod 3, a cam 14A for extending side position regulation and another cam 14B for pressing side position regulation are arranged at both surfaces of a stopper 13, and respective regulating positions are adjusted with motors 17A and 17B. According to the formation, the rubber 4 is deformed together with springs 10A and 10B after receiving reaction force of the piston rod 3, but the displacement of the rubber 4 and the springs 10A and 10B is regulated according to relative positions of the cams 14A and 14B and the stopper 13. The formation can freely regulate damping force.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an improvement in a suspension system for a vehicle that can reduce damping force to 1ull.

(Prior Art) The damping force characteristics required for a vehicle vary depending on the driving conditions. Therefore, for example, by configuring the damper's damping valve with a solenoid valve and driving the solenoid valve with an external electric signal, Many applications have already been filed for devices in which the damping force can be adjusted to different characteristics as required.

However, this device requires a solenoid valve for adjusting the damping force to be interposed in the hydraulic oil passage inside the damper, which poses a problem in that the structure is complicated and expensive.

On the other hand, although the damping force itself does not change, an air spring is arranged in series with the suspension spring as described in Japanese Patent Application Laid-open No. 58-85704, and the air spring absorbs high-frequency vibrations that cannot be absorbed by the suspension spring. There are also devices designed to absorb it.

(Problem to be solved by the invention) However, although this device can absorb high frequency vibrations,
The damping force cannot be variably adjusted, and the damping force characteristics cannot be changed depending on the operating conditions.

By the way, Fig. 10 (A) is a schematic diagram showing the operating principle of a general damper, whereas Fig. 1]2d (B) shows an elastic member such as an air spring between the damper and the vehicle body. (Spring constant K) is a schematic diagram when interposed, and the operating principle will be analyzed based on these.

In addition, in the general damper shown in Figure 10 (A), a rubber insulator is inserted into the damper mounting part between the damper and the vehicle body, but the spring constant of this rubber is usually much higher than that of a suspension spring. Therefore, it can be considered a rigid body.

Therefore, in the case of FIG. 10 (A>), when vibration of displacement xl is input from the lower side of the spring, only the damping force corresponding to the damping coefficient C of the damper is generated.

However, in the case of FIG. 10(B), when a vibration of displacement X is input, a vibration of a different displacement x2 is generated on the piston rod side by the elastic member.

In this case, the change in the ratio of the displacements x1 and X2 due to the vibration frequency ω is as shown in FIG. 11. The relative displacement between the piston rod and the cylinder (Xl-X2) gradually changes as ω increases, and becomes
+ = X 2, that is, (X, -X2) - 〇. (However, the mass (m) represents the total equivalent mass of the elastic member, piston rod, and piston.) If we look at this as a comparison of the damping force with and without the elastic member, the result is as shown in Figure 12. .

In other words, if there is no elastic member, the damping force does not change with respect to the vibration frequency, but if there is an elastic member, the damping force changes with the frequency, and if there is an elastic member, its natural frequency ( In other words, when the spring constant) changes, the damping force reduction rate also changes. In the figure, the spring constant Kn (n=
1.2.3.4...ω) is shown, and by changing the spring constant of the elastic member, the reduction rate of the damping force can be changed.

The present invention focuses on this point and provides a device in which a damping force adjusting means is attached to the outside of the damper, and the damping force can be adjusted freely with a relatively simple structure.

<Means for Solving the Problems> The present invention provides a vehicle suspension system in which a damper and a suspension spring are interposed in parallel between the vehicle body and the axle, and in which an elastic member is interposed between the damper and the vehicle body or the axle. At the same time, a means for regulating the elastic deformation lid of the elastic member is provided, and a means for adjusting the regulating position by the regulating means is provided.

(Function) For this reason, when the damper operates on the expansion side or the compression side, the elastic member deforms depending on the magnitude of the expansion load, but the damping force characteristics until the amount of deformation is regulated and the damping force characteristics after the restriction is The damping force characteristics will be different. Therefore, by adjusting the regulation position to Nil, the generated damping force characteristics change, and by adjusting this according to the operating conditions, it is possible to provide the required damping force.

(Example) Embodiments of the present invention will be described below based on the drawings.

In FIG. 1, a damper 1 is interposed between an axle and a vehicle body, and a suspension spring 2 that receives a load is also interposed in parallel with the damper 1.

Although not shown, a piston is housed inside the damper 1, and a damping valve is also provided to exert a predetermined damping force. They are connected via rubber 4 as shown in FIG.

The rubber 4 is formed into a donut shape, and a disk 6 fixed to the piston rod 3 via a nut 5 is embedded in the inner periphery of the rubber 4, and a rubber case 7 is formed so as to completely enclose the outer periphery of the rubber 4. It is fixed to a part of the vehicle body with bolts 11.

Note that one end of the suspension spring 2 is supported by the lower surface of the rubber case 7.

The rubber case 7 is formed into a cylindrical shape and is divided into two from the center, and adjusters 8A and 8B are screwed into flanges 7A and 7B that are concentric with the piston rod 3, respectively.

And each adjuster 8A, 8B has a retainer 9A, 9B.
are locked, adjusters 8A, 8B and retainers 9A, 9
A compression side spring 10A and a compression side spring LOB are interposed between the springs B and B, respectively. These springs 10A and IOB are connected to the rubber 4
When the elastic member is compressed toward the extension side or the compression side, it is compressed together with the elastic member, and constitutes a part of the elastic member.

However, these extension side and compression side springs IOA and 10B can be adjusted by changing the screwing positions of adjusters 8A and 8B.
The initial deflection can be adjusted independently.

Next, the rubber 4 as the elastic member, the spring IOA, 10B
As a means for regulating the amount of elastic deformation of the piston rod, a stopper 13 is fixed to the tip of the piston rod 3 by a nut 12, and cams located on both sides of the stopper 13 regulate the extension side position. 14A, and a cam 14B for regulating the pressure side position. These cams 14A and 14B are respectively cylindrical members concentric with the piston rod 3, and have a step-like shape A on the end surface of the cylinder, as shown unfolded in FIG.

Cam surface 1 changing to B, C, D and a, b, c, d
5 is formed.

Ring gears 16A and 16B are fixed to the flange portions as a means for adjusting the regulating position of the elastic member by changing the position of each cam 14A and 14B with respect to the stopper 13, and one ring gear 16A has an extension side motor 17.
A's pinion gear 118A is also the other ring gear 1
The pinion gears 18B of the pressure side motor 17B are engaged with the pinion gears 6B, respectively. Therefore, when the motors 17A, 17B are rotated, the cams 14A, 14B rotate, and the position of the cam surface 15 that engages with the stopper 13 changes.

These expansion side and compression side motors 17A, 17B are connected to the cam 14A.
, 14B, stopper 13, etc., and is attached to a cylindrical housing 19, which is fixed to the rubber case 7 with a tightening bolt 20. In addition, 21
are springs that hold each cam 14A, 14B.

The system is constructed as described above, and its operation will be explained next.

When the damper 1 causes a compression operation due to the action of a load on the sprung side or under the sprung side, the rubber 4 tends to be compressed together with the compression side spring IOB due to the reaction force of the piston rod 3. However, if the cam 14B is positioned as shown in FIG. 2, the stopper 13 cannot be displaced by the cam 14B, and the cam 14B is fixed to the rubber case 7 via the housing 19, so No compressive load is applied to the compression side spring IOB, but if the cam 14B is rotated by the compression side motor 17B and is, for example, at stage (C) of the cam surface 15, a gap is created between the stopper 13 and the piston rod. 3 can be relatively displaced by that gap.

In this way, the rubber 4 and the compression spring IOB are compressed by the amount of relative displacement regulated by the cam 14B and the stopper 13. After this, when the stopper 13 hits the cam 14B,
Further elastic deformation is prevented, and the piston rod 3 becomes integral with the vehicle body.

FIG. 3 is a characteristic diagram showing the relationship between the load and displacement of these elastic members, and when stroking toward the compression side, (
Up to point C), the load and elastic displacement correspond to each other in a proportional relationship, but once the load hits cam 14B at point (C), the amount of displacement does not change even if the load increases, and cam 14B
The position at which the stopper 13 hits can be changed by rotating the compression side motor 17B, and can be freely adjusted depending on the operating conditions.

When the damper 1 operates on the expansion side, the piston rod 3 is pulled, so a load acts on the rubber 4 in the opposite direction, and at the same time, the expansion side spring IOA is compressed. Compressive deformation in this case is also allowed until the stopper 13 is regulated by the extension side cam 14A, and beyond that, the piston rod 3 becomes integral with the vehicle body.

Next, the extension side deforms with these elastic deformations of the rubber 4,
The initial deflection of the compression side springs IOA and IOB can be changed by adjusting the positions of the adjusters 8A and 8B. As shown in Fig. 4, if the springs 10A and IOB are compressed in advance, the springs IOA and 10B can be Elastic deformation does not occur until the set initial load is exceeded, after which deformation begins.

For example, when operating on the extension side, if the initial 101#f load is changed like A', A'', the elastic members (rubber 4 and extension spring 10A) will not deform until a greater load is applied. First, during this period, the piston rod 3 becomes integral with the vehicle body, and then the piston rod 3 produces a relative displacement with respect to the vehicle body equal to the amount of deformation of the elastic member.Then, after that, the operation is regulated by the stopper 13. After that, the piston rod 3 becomes integral with the vehicle body again as described above.

Therefore, if this is shown as a damping force characteristic, it will be as shown in No. 51.

In other words, until the set initial load is exceeded, the spring constant of the elastic member is ω, and the damping force characteristics are the same as in Figure 10 (same as the general damper in A>), and the initial load When Kn is exceeded, the damping force characteristic becomes corresponding to the spring constant Kn of the elastic member, and when the elastic deformation is further restricted by the stopper 13, the damping force characteristic shifts again to the same damping force characteristic as when = (1).

These changes in damping force characteristics are based on the cam 14A.
, 14B, it is possible to provide the required damping force characteristics by controlling the drive of the motors 17A, 17B according to the operating conditions, for example.

Next, the embodiment shown in FIG. 6 will be described. In this embodiment, the rubber 4 is removed, and the extension spring IOA and the compression spring Lo are
The spring constant can be set only by B. At this time, as a stopper for regulating the position of the piston rod 3, a screw 25 is screwed into the case 7 coaxially with the piston rod 3, and is interlocked with a motor (not shown) via a worm 26 and a worm wheel 27.
By changing the position of the screw 25, the pressure wII11 of the compression side spring IOB is regulated.

The compression of the extension spring IOA is regulated by a stopper tube 28 screwed into the case 7 from the outer circumferential side of the piston rod 3. However, this stopper cylinder 28 may also be driven by a motor like the other screw 25, or conversely, the screw 25 may be adjusted manually.

In addition, although the initial loads of the extension side and compression side springs 10A and IOH cannot be adjusted in this embodiment,
It goes without saying that if the adjusters 8A and 8B are provided as in the embodiment shown in FIG.

In this case, by changing the spring constants of the springs IOA and IOH on the expansion and compression sides, the damping force characteristics on the expansion and compression sides can be made different.

In the embodiment shown in FIG. 7, the extension side spring IOA and the compression side spring 10B are replaced with a single common spring 30, and washer-like stoppers 31 and 32 fixed to the piston rod 3.
A spring 30 is interposed between them, these stoppers 31 and 32 are covered with a case 7 from the outside, and a cam 34 driven by a motor 33 is provided between the stoppers 31 and 32.

The cam 34 is formed like a seventh g (A), and its rotational position regulates the minimum distance between the stoppers 31 and 32.

Therefore, the state fi! of FIG. In this case, the spring 30 is not compressed, but due to the rotation of the force l\34, the stopper 31
．． 32, the piston rod 3 can compress the spring 30 by that amount.

In this embodiment, since the spring 30 is common, the damping force characteristics cannot be changed between the expansion side and the compression side, and the initial compression load is also the same.

In the embodiment shown in FIG. 8, only rubber 4 is used as the elastic member.

Eye bracket 40 attached to the tip of piston rod 3
A rubber 4 is placed inside the rubber 4, and a fixing bolt 41 to be attached to the vehicle body is passed through the center of the rubber 4.
A cam 43 that engages and disengages from the inner periphery of the eye bracket 40 is fitted into the collar 42 inserted into the collar 42, and the cam 43 restricts displacement of the eye bracket 40.

In the state shown in FIG. 9, the cam 43 is engaged with the inner circumference of the eye bracket 40, so the rubber 4 cannot be deformed.
In this case, the spring constant is = ■, but when the cam 43 is manually rotated 90 degrees as shown by the dashed line, the rubber 4 can be compressed in the axial direction of the piston rod 3, so i
l! The li damping force characteristics change.

It is obvious that the shape of the cam 43 may be such that the cam surface changes in multiple stages as shown in FIG. 7(A).

(Effects of the Invention) As described above, according to the present invention, when the damper operates on the extension side or the compression side, the elastic member deforms depending on the magnitude of the extension load, and the amount of deformation is regulated. The damping force characteristics and the damping force characteristics after regulation will be different. Therefore, by adjusting the regulation position, the generated damping force characteristics can be changed according to the request, and it can be adjusted to the operating conditions etc. by simple means. There is an effect that an optimum damping force can be applied correspondingly.

[Brief explanation of drawings]

Fig. 1 is a sectional view showing the first embodiment of the present invention, Fig. 2 is an exploded view of the cam, Figs. 3 and 4 are characteristic diagrams showing the load-stroke characteristics of the elastic member, and Fig. 5. 6 is a damping force characteristic diagram showing the relationship between stroke and damping force on the rebound side and compression side.
The figure is a sectional view of the main part of the second embodiment, Fig. 7 is a sectional view of the main part of the third embodiment, Fig. 7 (A) is a front view of the cam, and Fig. 8 is a sectional view of the main part of the fourth embodiment. The main part sectional view and FIG. 9 are also front views. Figure 10 (A>, [3) is a schematic diagram showing the operating principle of the damper, Figure 11 is a characteristic diagram showing the relationship between vibration frequency and relative displacement, and Figure 12 is the vibration when changing the spring constant. It is a characteristic diagram showing the relationship between frequency and damping force reduction rate. 1... Damper, 2... Suspension spring, 3... Piston rod, 4... Rubber, 7... Case, 10A,
10B... Spring, 13... Stopper, 14A, 14
B...Cam, 17A, 17B...Motor patent applicant Kayabae Gyo Co., Ltd. Figure 8 Figure 9 X 0-Next U.

Claims (1)

[Claims] In a vehicle suspension system in which a damper and a suspension spring are interposed in parallel between the vehicle body and the axle, an elastic member is interposed between the damper and the vehicle body or the axle, and the amount of elastic deformation of the elastic member is regulated. 1. A suspension system for a vehicle, comprising: a means for regulating the regulating means; and a means for adjusting the regulating position of the regulating means.