JPS6012322A - Four link suspension - Google Patents

Abstract

PURPOSE:To eliminate low speed stuffy noise by arranging a shock absorber between the end section of upper or lower control link of four-link suspension and chassis. CONSTITUTION:An axle housing 12 can roll up and down while being supported by a pair of upper control links 14 and lower control links 16. Since they 14, 16 are inclined against the center line of chassis, lateral motion of said housing 12 can be suppressed. Since a pair of shock absorbers 18 are arranged between the rear end of lower control link 16 and chassis, the shock absorber is never pushed up through wind-up vibration to eliminate the stuffy noise.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a four-link suspension for an automobile, and more particularly to a four-link rear suspension.

The four-sunk type Suspensegon is equipped with a pair of upper control links and a pair of lower control links, and the axle housing arranged in the width direction of the vehicle body is connected to the upper control link in each of the two parts spaced apart in the width direction. Supported by the link and lower control link, a pair of coil springs are installed between the axle housing or lower control link and the vehicle body, and a pair of shock absorbers are installed between the axle housing and the vehicle body to reduce vibrations from the road surface. This prevents shock from being transmitted to the vehicle body.

Incidentally, the pair of shock absorbers are usually connected to both ends of the axle housing, respectively, in order to quickly damp vibrations of the unsprung portion and the vehicle body, and improve riding comfort, ground contact, and steering stability. As a result, when a four-link suspension is used as a rear suspension, when wind-up vibration occurs in which the axle housing is rocked about its axis, the shock absorber receives an upward force, and this force is applied to the vehicle body. A low-speed muffled sound is generated when inputting data.

In order to deal with the low-speed muffled noise, countermeasures have been taken, such as reducing the spring constant of the bushing placed at the connection of the shock absorber to the vehicle body, and making the damping characteristics of the shock absorber different at low speeds and at high speeds. It is being

However, the above-mentioned measures are at odds with each other in terms of ride comfort, maneuverability, stability, durability, quality, etc., so their effectiveness is limited.
Low-speed muffled noise continues to cause discomfort to vehicle occupants.

Therefore, an object of the present invention is to provide a four-link suspension that can reduce low-speed muffled noise without impairing ride comfort, maneuverability, stability, durability, quality, or other functions.

The four-link type suspension according to the present invention includes: an axle housing disposed in the width direction of a vehicle body; a pair of upper control links pivotally connected to two portions of the axle housing spaced apart in the width direction; a pair of lower control links that are respectively pivotally connected to two parts spaced one interval apart in the width direction of the axle housing, and a lower end of each of the lower control links or each of the upper links; and a shock absorber connected to the vehicle body at an upper end.

When a wind-up vibration occurs in which the axle housing swings about its axis while the automobile is running, the lower control link (or up control link) swings along with the swing of the axle housing. However, even when the lower control link swings, the movement of the lower control link in the axial direction is large, while the movement of the lower control link in the vertical direction is small, so the vertical movement applied to the shock absorber is The vibration input becomes smaller.

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

As shown in FIGS. 1 and 2, the four-sunk type Svenge 10 includes an axle housing 12, a pair of upper control links 14, a pair of lower control links 16, and a pair of shock absorbers 18. include.

The axle housing 12 is arranged in the width direction of the vehicle body 20, and supports a rear wheel in the illustrated example. A drive shaft (not shown) is rotatably supported inside this axle housing 12. The drive shaft transmits the rotational force transmitted from the propeller shaft 22 via the differential gear device 24 to the wheels 26 attached to both ends thereof, thereby rotating the wheels 26.

The pair of upper control links 14 are arranged at intervals in the width direction of the vehicle body. Each seven-horn five control link 14 has an eye 28 at its front end and an eye 29 at its rear end. The front eye 28 of each upper control link 14 is connected to the bracket 30 of the vehicle body 20.
The upper control links 14ji are pivotally connected to each other by bolts and nuts 32, and each upper control link 14ji extends in the longitudinal direction of the vehicle body. In the example shown in FIGS. 1 and 2, each upper control link 14 is inclined with respect to the center line in the longitudinal direction of the vehicle (parallel to the axis of the propeller shaft 22), and the rear eye 29 is The eye 29 at the rear of each of the seven control links 14 projects upwardly from two parts of the axle housing 12 spaced apart in the width direction of the vehicle body. It is pivotally connected to a bracket 34 with bolts and nuts 36.A rubber bush (
(not shown) and a bolt is passed through this bushing to prevent vibrations from being transmitted through the upper control link 14.

The pair of lower control links 16 are arranged at intervals in the width direction of the vehicle body. Each lower control link 16
has an eye 38 at its front end and an eye 39 at its rear end, and further has a threaded connection 41 projecting axially from the rear eye 39. The eye 38 in front of each lower control link 16 is connected to the vehicle body 2.
The lower control link 16 is pivotally connected to the bracket 42 of the lower control unit 44 by a bracket 44, and each lower control link 16 extends in the longitudinal direction of the vehicle body. In the example shown in FIGS. 1 and 2, each lower control link 16 is inclined with respect to the longitudinal center line of the vehicle body, and the rear eye 39 is aligned with the front eye 38.
It is located further outward in the width direction of the vehicle body. The rear eye 39 of each lower control link 16 is pivotally connected by a port nut 48 to brackets 46 that respectively project downward from two parts of the axle housing 12 spaced apart in the width direction of the vehicle body. Each eye ratio is equipped with a rubber bushing like the eye of the upper control link. As will be described later, the connecting portion 41 connects the shock absorber 18, and the load acting here is transferred to the lower control link 16 sandwiched between the eyes 38 and 39.
Since the diameter of the connecting portion 41 is smaller than that of the portion shown in FIG.

The axle housing 12 is supported by a pair of seven-way control links 14 and a pair of lower control links 16, and can swing in the vertical direction. Since the pair of upper control links 14 and the pair of lower control links 16 are inclined with respect to the center line of the vehicle body, movement of the axle housing 12 in the width direction of the vehicle body is suppressed.

The pair of shock absorbers 18 have a piston slidably disposed inside a cylinder, and both a so-called twin tube type and a monotube type can be used. In the pair of shock absorbers 18, one shock absorber 18 corresponds to one lower control link 16.
It is installed so that it extends upward from the top. Each shock absorber 18 has an eye 50 at its lower end that passes through the connecting portion 41 of each lower control link 16, a pair of washers 52 are placed on both sides of the eye 50, and a nut 54 is inserted into the screw 40 of the connecting portion 41. The lower control link 16 is connected to the lower control link 16 by being screwed into the lower control link 16. A rubber bushing is attached to the eye 50. Eye 5 on shock absorber 18
0, and on the other hand, an eye whose axis is perpendicular to the lower control link 16 is provided, and the screw of the shock absorber 18 is connected to the lower control link 1.
It is also possible to connect the shock absorber 18 and the lower control link 16 by penetrating the eye of No. 6 and screwing a nut thereon.

The upper end of each shock absorber 18 is passed through a pair of bushings 56 disposed above and below the vehicle body 20, and further through a retainer 58 disposed above and below each bushing 56, and is connected to a screw provided at the end. It is connected to the vehicle body 20 by screwing together a nut 60.

The pair of coil springs 62 are installed between the axle housing 12 and the vehicle body 20 so that one coil spring 62 is near each shock absorber 18 , and works together with the pair of shock absorbers 18 to Attenuates vibrations applied to

The four-link type suspension 70 shown in FIG. 3 includes a pair of upper control links 72 supporting the axle housing 12, a pair of lower control links 74, and a pair of shock absorbers 18. is the same as However, in the four-link suspension 70 of this example, the pair of upper control links 72 and the pair of lower control links 74 are arranged substantially parallel to the center line of the vehicle body, and the axle housing 12 is disposed in the width direction of the vehicle body. The difference is that a lateral rod 76 is provided, one end of which is pivotally connected to the axle housing 12, and the other end of which extends in the width direction of the vehicle body and is pivotally connected to the vehicle body, in order to prevent the vehicle from moving. The other configuration of this example is the same as the four-link suspension IO.

A four-link suspension 80 shown in FIG. 4 includes a pair of upper control links 72 and a pair of lower control links 82 that support the axle housing 12 and are substantially parallel to the centerline of the vehicle body, and further includes a pair of shock absorbers. 18 and a lateral rod 76, it is the same as the four-link type suspension 70 described above. However, the four-link type suspension 80 of this example is different in that the lower control link 82 is formed wider and a coil spring 62 is installed between the lower control link 82 and the vehicle body. The other configurations of this example are the same as the four-link suspension 10.

When a car on which the four-link suspension lO is installed travels and wind-up vibration occurs, the axle housing 12 swings about its axis. Along with this swing, the lower control link 16 also swings. However, since the pivoting end of the lower control link 16 to the vehicle body, which is the swinging fulcrum, is separated forward by a relatively large distance from the axis of the axle housing 12, the pivot point between the lower control link 16 and the axle housing 12 is Although the landing end moves largely in the axial direction of the lower control link 16, the amount of movement in the vertical direction is small.As a result, the amount of vertical movement of the shock absorber 18 is also small. The force that raises the vertical thrust hardly acts on the shock absorber 18, and the muffled noise inside the vehicle caused by this force remains low over a wide range of engine speeds, as shown in A in Figure 5. It is maintained. In contrast, with conventional four-link suspensions, the shock absorber was connected to the axle housing, so the amount of vibration of the axle housing was directly input to the shock absorber, creating a large force that raised the shock absorber. As shown in Fig. 5B, especially when the engine speed was low, a loud muffled sound was being generated. As is clear from this figure, the present invention is particularly effective at low speeds.

If the axle housing 12 bounces while the car is running,
During rebound, the shock absorber 18 cooperates with the coil spring 62 to damp the vibrations of the axle housing 12, much like a conventional shock absorber. That is, in this case, the axle housing 12
The vertical vibration applied to the shock absorber 18
, so damping is achieved by the action of the valve mechanism provided in the shock absorber 18.

In the above example, the lower end of the shock absorber is connected to the lower control link behind the rear eye of the lower control link. Alternatively, the lower end of the shock absorber may be connected to the lower control link forward of the rear eye. It is also possible to connect the lower end of the shock absorber to the upper control link. In this case, if the space between the upper control link and the vehicle body is narrow compared to the length of the shock absorber, a crank-shaped connection part is provided on the upper control link at a position where the lower end of the shock absorber is connected. All you have to do is move it downwards.

According to the present invention, since the lower end of the shock absorber is connected to the lower control link or the upper control link, even if wind-up vibration occurs, such as when the axle housing is rocked around its axis, , the force that pushes the shock absorber up and down has almost no effect on the shock absorber. As a result, it is possible to reduce the occurrence of low-speed muffled noise in particular, and to reduce the discomfort caused to the occupants of the vehicle. Moreover, when the axle housing bounces or rebounds, it acts exactly the same as before, damping vibrations.

According to the present invention, in order to deal with low-speed muffled noise, the spring constant of the bushing arranged at the connection part of the shock absorber to the vehicle body is made small, and the damping characteristics of the shock absorber are made different between low speed and high speed. It is not necessary to take measures such as lowering the shock absorber, and durability and quality can be improved while maintaining the original functions of the shock absorber, such as ride comfort, maneuverability, and stability.

[Brief explanation of the drawing]

Fig. 1 is a side view of a four-sunk type suspension according to the present invention, Fig. 2 is a perspective view, Fig. 3 is a perspective view showing another example of a four-link type suspension, and Fig. 4 is a four-link type suspension. FIG. 5 is a perspective view showing still another example, and FIG. 5 is a characteristic diagram showing the relationship between engine speed and sound pressure level. 10.70. ao; four-link suspension 12, axle housing; 14; upper control link; l6; lower control link; 18; shock absorber; 41; connection portion; 62; coil spring. Agent Patent Attorney Nobuyuki Matsunaga Figure 1

Claims (1)

[Claims] an axle housing disposed in the width direction of the vehicle body; a pair of upper control links pivotally connected to two portions of the axle housing spaced apart in the width direction; a pair of lower control links that are respectively pivotally connected to the two parts that are placed, and connected at one end of each of the lower control links or each of the seven control links;
``A four-sunk type Suvenge M, including a shock absorber connected to the vehicle body at one end.