JPS6010162Y2 - parallel link suspension system - Google Patents

Description

[Detailed description of the invention] The invention includes a pair of links that are swingably connected to the vehicle body at one end and to the wheel support at the other end, and arranged in parallel in the width direction of the vehicle body across the front and rear of the vehicle body. Relating to a parallel link suspension system.

A full trailing arm type in which a swinging arm to which a wheel is mounted via a wheel support is supported in a parallelogram by two links parallel to the longitudinal direction of the vehicle body; Both semi-trailing arm and swing axle suspension systems, which are triangularly supported by two links that are diagonal to the longitudinal direction of the vehicle, are designed to handle the effects of longitudinal and lateral forces acting on the wheels, for example. If the brakes are applied during a turn, an aperture may occur and the steering stability may be impaired.Also, when driving on uneven ground, the vehicle may be in a toe-out state, which may cause problems with driving stability. be.

In view of the above, a parallel link type suspension comprising a pair of links that are swingably connected to the vehicle body at one end and to the wheel support at the other end and arranged in parallel in the width direction of the vehicle body across the front and rear of the vehicle body. A device has been developed and is in use.

In this parallel link suspension system, two generally parallel links form a parallelogram link together with the vehicle body and wheel supports, and when a longitudinal force is applied to the wheels, the wheel supports move almost in parallel. It is expected that there will be no toe change.

However, in reality, due to the influence of the compliance of the bushings provided at the connection points between each link and the vehicle body and the wheel support, it is difficult to completely eliminate toe change, and there is usually a slight toe-out condition. The aperture tendency is exhibited during the above-mentioned turning.

Furthermore, even if the vehicle were to ideally move in parallel, it would not actively create toe-in, so it would not be possible to increase steering stability by imparting a tendency to understeer, especially when turning.

Therefore, an object of the present invention is to positively apply toe-in by utilizing an external force exerted on the wheels, thereby solving the above-mentioned disadvantages of the parallel link type suspension system.

According to the present invention, the parallel link type includes a pair of links that are swingably connected to the vehicle body at one end and to the wheel support at the other end and are arranged in parallel in the width direction of the vehicle body across the front and rear of the vehicle body. A suspension system is provided.

In this suspension system, one link is formed of a highly flexible member and is curved so as to be convex in either the longitudinal direction of the vehicle body when no force is applied, and the other link is formed of a rigid body. and a rigid restraint link with one end swingably connected to the middle of the highly flexible link, and the other end of the restraint link is connected to the It is characterized in that it is swingably connected to the rigid link, the wheel support, or a rigid part of the vehicle body at a position such that the highly flexible link straightens when subjected to a force.

As mentioned above, what is required in a normal vehicle is, for example, to provide toe-in and weak understeer when turning.

Therefore, in this case, the link located on the rear side of the vehicle body is made of a highly flexible member and is formed to be convex toward the front or rear direction of the vehicle body, and the link located on the front side of the vehicle body is Make it a rigid body.

However, for special vehicles where it is desired to create an aperture when turning, the links located on the front side of the vehicle body should be made of a highly flexible material and be convex toward the front or rear of the vehicle body. The link located on the rear side of the vehicle body is a rigid body.

In the suspension system configured according to the present invention, when a force is applied to the wheel, the linear distance between the connection points between the highly flexible link and the vehicle body and the wheel support is reduced by the action of the restraining link. The toe-in is always longer than the straight-line distance when no force is applied, while the straight-line distance between the connection points of the rigid link with the vehicle body and with the wheel support remains unchanged, so that the toe-in is generally Toe-out will be given in special cases.

The highly flexible link is made of a member that can easily bend back and forth, such as a steel plate with a rectangular cross section or a leaf spring, while the rigid link has a sufficient degree of bending compared to the above-mentioned link. Formed as a member and/or form that is small enough to be treated as a substantially rigid body.

In this way, highly flexible members and rigid bodies are
For example, even if the rigid body itself undergoes elastic deformation during use, the present invention can be implemented as long as the degree of deformation is sufficiently small compared to the degree of deformation of the flexible link. be done.

Also, the restraint link provided according to the invention may be one or more.

Embodiments of the present invention will be described in detail below with reference to the drawings.

Note that in all of the following examples, the rear link is made of a highly flexible member as described above, and the front link is made of a rigid body, but the opposite example is obvious from the following examples. .

As shown in FIG. 1, a pair of parallel links 10 and 12 are swingably connected at one end to the vehicle body 14 at points A and C, and at the other end to the wheel support 16 at points B and D, respectively. A wheel 20 is mounted on the spindle 18 of the wheel support 16 .

Among the links, the link 12 located on the rear side of the vehicle body is made of a highly flexible member and is curved so as to be convex toward the front side of the vehicle body, and the other link 10 is made of a rigid body. There is.

A rigid restraint link 22 is arranged between the intermediate point E of the link 12 and the point B, which is the connection point between the link 10 and the wheel support 16, and is connected to each point so as to be swingable. has been done.

In addition to the above configuration, members such as strut bars and stabilizers are provided in the parallel link suspension system, but these members are omitted for convenience of explanation.

The same applies to the following examples. In short, the rear link 1
2 is made of a highly flexible member and is convex in the front direction, and a restraining link is provided between this link and a rigid portion, in this example, point B, and the other configurations are substantially the same as the conventional one. It can be the same as the parallel link suspension system.

In Fig. 1, it is assumed that a backward force F is applied to the grounding point O of the wheel 20 (an example of such a force is a sudden deceleration caused by an uneven road or when the accelerator pedal is suddenly released). (assuming a power-off condition), the parallel links 10.12 tend to deform to form a parallelogram AB1DIC.

At this time, B1. D□ will rotate around points A and C, respectively.

In this case, B1 rotates using the arm length t of CE as a radius, whereas the point E of the rear link 12 tries to rotate around the point C using the arm length S of CE as a radius. The amount of movement to point B is smaller than that at point B.

Therefore, the movement of point E (B
2) and the movement (El) of point E restricted by the link 12 interfere, and the movement restricted by the constraint link 22 becomes larger.

However, as mentioned above, the link 12 is a highly flexible member and is curved so as to be convex toward the front.
Due to the movement of the restraint link 22, point E moves to point B2,
The link 12 becomes straight so that the degree of curvature is reduced, and Dl actually moves to point D2.

In this case, the link 12 is not completely straight, but in the present invention, "straightening" means reducing the degree of curvature given in advance to the highly flexible link, and making it more straight. It means to get close to a straight line.

Since the above-mentioned point D2 has a relationship of B=6EQ, the point D2 comes out to the outside of the vehicle body.

As a result, the wheel supports supported by the links 102 and 122 formed by deforming the parallel links 10.12 are located closer to the center of the vehicle body toward the front, as indicated by 162, so that the tires 202 mounted on the spindle 182 are It is placed in a toe-in state.

When a forward force F is applied to the wheel 20 (for example, assuming a power-on state), the link 12 is deformed as shown in FIG.

That is, the force F tends to deform the parallel links 10.12 so as to form a parallelogram AB3D3C.

At this time, B3? D3 will rotate around points A and C, respectively, but in the same way as above, point B3
Since the amount of movement of point E on link 12 toward B3 is small compared to the amount of movement of , this point E is interfered with by restraint link 22, moves to connection RC4, and link 12 is deformed so as to be straightened. D4 is actually the point D4 where oil=AD4
It moves to the outside of the car body.

As a result, the wheel support 164 is supported by the links 104, 124 formed by deforming the links 10.12.
As in the previous example, since the front side is closer to the center of the vehicle body, the tire 204 mounted on the spindle 184 is in a toe-in state.

When a force F in a lateral direction (from the outside of the vehicle body toward the center) is applied to the wheel 20 (for example, when turning), the link 12 is deformed as shown in FIG. 3.

That is, due to the force F, the parallel link 10.12 tends to move in parallel in the direction of its axis and deform so as to form a quadrilateral A3B5D5C5.

However, the component of the force applied to point B is the constraint link 22.
As a result, point E is pushed out by this force, and the point that should normally move to B5 is moved to B6, and the link 12 is deformed so as to be straightened.
B5 draws an arc centered on the point and moves to B6, and D5 is actually the point D where CD=C5D5=C5D6
Move to step 6 and exit outside the car body.

As a result, the wheel support 166 is supported by the links 106, 126 formed by deforming the links 10.12.
As with each side above, the front side is closer to the center of the vehicle body, so
The tire 206 mounted on the spindle 186 is brought into a toe-in state.

In the above example, the spindle 18 is located in front of the wheel support 16, that is, the front rigid link 10 is located approximately on an extension of the spindle 18.

This is preferable because the following effects can be expected.

For example, use straight links of equal length as links 10 and 12, use a highly flexible link as link 10 located on the front side of the vehicle body, and place a restraining link between the middle of the front links and, for example, point D. If positioned, it is possible to obtain a toe-in condition when turning, etc., similarly to the suspension system of the present invention.

However, in order to realize such a suspension system, it is better to receive lateral force with a rigid link than with a flexible link, so the rear rigid link must be positioned on the extension line of the spindle. Each member will be placed in .

Therefore, the flexible links are located on the front side of the vehicle body, but this front link may interfere with other parts, or the positional relationship with the strut bar, which receives the longitudinal force acting on the suspension system, may be difficult. There are major restrictions.

Such inconveniences can be solved according to the above example.

However, the spindle 18 may be located at the center of the length of the wheel support 16 in the longitudinal direction, or may be provided at a point distributed in an arbitrary proportion of the length in the longitudinal direction.

The above is an example in which one end of the restraint link 22 is swingably connected to the link 12 at point E, and the other end is swingably connected to the connecting portion between link 10 and wheel support 16 at point B. The invention is not limited to such connections.

The point is that when a force is applied to a wheel, the straight-line distance between the highly flexible link and the connection point with the vehicle body and the wheel support becomes shorter than the straight-line distance when no force is applied, due to the action of the restraining link. The constraint links may be arranged so that they are always made long.

For example, as shown in FIG.
It may be swingably connected to the link 10 at a point (in this case, the link 10 itself does not swing at the point G); in this case, the lengths of S (Paulownia) and U (λG) may be adjusted as appropriate. By setting, the amount of change in toe-in can be changed.

On each side, the link 12 is convex toward the front side of the vehicle body, but it may be convex toward the rear side of the vehicle body.

Furthermore, the constraint link can be connected outside each side, between AC, between BD, etc., as long as that part is a rigid body.

However, the other end of the restraining link is chosen in a position that allows the highly flexible link to straighten when the wheel, and therefore the wheel support, is subjected to longitudinal or lateral forces.

On each side above, the connection point of link 10.12 is AB=
CD and AC=BD, but for example, the distance between the vehicle body side connection points A and C of each link 10.12 is set to be smaller than the distance between the wheel support side connection points B and D of each link. Alternatively, each link 10.12 may have a different length.

Furthermore, it can serve as both, that is, AC) BD and A
The present invention can also be implemented in an arrangement where B=#CD.

In the present invention, "parallel" has the above meaning.

According to the present invention, by adopting one flexible link on the rear side, curving this link in a convex shape toward the front or rear of the vehicle body, and arranging a link to restrain this link, it is possible to It becomes possible to suppress toe changes or force toe-in, and it becomes possible to significantly improve driving stability on uneven roads and when turning.

Furthermore, by arranging the bendable link at the front in a curved state, it is also possible to create a toe-out state, which is the opposite of the above, and can be applied to cases where such a vehicle is required.

Further, if the amount of deflection given in advance to a link that is easily deflected is suppressed to a small value, the amount of extension of this link is limited, so the amount of change in toe-in can be regulated so as not to exceed a certain value.

Furthermore, by appropriately selecting the characteristics of the bushing provided at the attachment part of the restraint link, the bending characteristics of the link, the attachment position of the restraint link, etc., it is possible to add an appropriate toe-in change, and the geometry of the suspension system can be adjusted. It has excellent effects such as being able to change the feeling characteristics depending on the type of vehicle, such as a sporty car or a general car, without changing the vehicle layout.

[Brief explanation of drawings]

Figures 1 to 3 are explanatory diagrams showing the planar state of the suspension system of the present invention. Figure 1 shows the case when a backward force is applied to the wheel, and Figure 2 shows the case when a forward force is applied to the wheel. , the third
The figures each show the case when a lateral force is applied to the wheel, and in each figure, the thin solid line shows the state before the change, the imaginary line shows the state in the process of change, and Figure 4 shows another example. It is an explanatory view showing a planar state before change. 10.12...Link, 14...Car body, 16...Wheel support, 18...Spindle, 20...Wheel, 22 ...Restricted link.

Claims (1)

[Scope of utility model registration request] A pair of links that are swingably connected to the vehicle body at one end and to the wheel support at the other end and are arranged in parallel in the width direction of the vehicle body across the front and rear of the vehicle body, one link being a highly flexible member. A pair of links formed by and curved so as to be convex in either of the longitudinal directions of the vehicle body when no force is applied, the other link being formed of a rigid body, and an intermediate link between the highly flexible link. a rigid restraining link whose one end is swingably connected to the rigid restraining link, and the other end of the restraining link straightens the highly flexible link when the wheel support receives a longitudinal force or a lateral force. a parallel link suspension which is swingably connected to said rigid link or wheel support or to a rigid part of a vehicle body in such a position;