JPH0413210Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field The present invention relates to a front wheel suspension system for a vehicle such as an automobile.

2. Description of the Related Art In general, a front wheel suspension system for a vehicle has a structure in which one end of a lower arm is pivotally supported on the vehicle body, the other end of the lower arm indirectly supports the front wheel via a knuckle arm, etc., and the lower arm is supported by a strut bar. to accomplish. Conventionally, strut bars have been provided to function independently for each of the left and right front wheels, and the force applied to these front wheels in the longitudinal direction of the vehicle is received by each strut bar bushing (rubber bushing). In such a configuration, the phenomenon in which longitudinal vibration of the suspension due to unbalanced tires is transmitted to the steering wheel is called flutter. The level and speed range of this phenomenon change depending on the front and rear stiffness of the suspension. Therefore, the maximum speed according to domestic and American regulations is 80 to 100 km/h, so if the flutter is made to occur at vehicle speeds above this range, it is possible to prevent the flutter from being felt. However, if the generated vehicle speed is increased to a high speed side, the front and rear stiffness of the suspension will increase, which will worsen the stiffness phenomenon when driving over concrete joints, etc.

Problems to be Solved by the Invention The present invention attempts to reduce the flutter level without worsening the harshness.

Means for Solving the Problems That is, the configuration of the present invention is such that the outer ends of the left and right lower arms support the wheels via knuckle arms, etc., and the body-mounted inner ends of the left and right lower arms are connected in the longitudinal direction of the vehicle. It is characterized by extending in opposite directions and connecting these extension ends with a rigid member.

Function: Therefore, when the unbalanced positions of the left and right front wheels become in phase and a forcing force is applied in the longitudinal direction of the vehicle, no internal force is generated in the rigid member, and only the longitudinal rigidity of the strut bending is applied. Ride comfort is not affected. Furthermore, when the unbalanced positions of the left and right front wheels become opposite to each other, the movement of the lower arm in the front and back direction also becomes opposite and reaches its maximum, but the stiffness of the suspension system increases in the front and rear direction due to the rigid member, and the lower arm moves out of phase. It becomes difficult to move. Increasing the rigidity of the suspension system in the longitudinal direction means that the peak of the flutter level will be in a high vehicle speed range, making it possible to reduce the flutter level at normal vehicle speeds.

Embodiments Next, the present invention will be explained according to embodiments shown in the drawings.

Fig. 1 shows left and right front wheels 1, 1, spindle shafts 2, 2, knuckle arms 3, 3, tie rod 4,
4, lower arms 5, 5, strut bars 6, 6, and strut cushions 7, 7 are shown, and the lower arm 5 is provided with a rigid member 8, the details of which are shown in FIG.

That is, as shown in FIG. 3, an extended outer tube section 9 is formed at the inner end of the lower arm 5, a lower arm bushing 10 is inserted into the base of the extended outer tube section, and the inner end is inserted through the lower arm bushing 10. Place the tube 11 on the body side 1
It is fixed at 2. Further, the extended outer tube section 9 has a rigid member 8 rotatably attached to the distal end side opposite to its base, and the other end of the rigid member 8 is similarly attached to the distal end side of the extended outer tube of the other lower arm 5.

The rigid member 8 can be separated into a tubular part 13 and a rod-shaped part 14, and the rod-shaped part 14 is slidably inserted into the tubular part 13, and as shown in FIG. are connected.
This stopper 15 is actuated by an electromagnet 16 that is excited by a vehicle speed sensor (not shown), and when the electromagnet 16 is not excited, the stopper 15 is moved by a spring 17 in a direction away from the bar-shaped part 14, and the stopper 15 is moved away from the bar-shaped part 14. The tubular portion 13 is separated.

In this embodiment, as shown in Fig. 5, the vehicle speed is 80
Km/h, the electromagnet 16 is not excited and is in the OFF state, and between 80 Km/h and 120 Km/h, the electromagnet 16 is energized and is in the ON state, and the rigid member 8
The tubular part 13 and the rod part 14 are connected, and the peak vehicle speed of flutter is moved to a high place of 120 km/h or more, and flutter is no longer felt between 80 km/h and 120 km/h. At speeds above 120 km/h, the electromagnet 16 is turned off again, and the peak vehicle speed of flutter becomes low, so flutter is not felt. In this way, the electromagnet 16 is turned on depending on the vehicle speed.
By turning it off and moving the peak vehicle speed of flutter, it is possible to reduce the level of flutter across the entire vehicle speed range.

To explain in more detail the function of the rigid member 8 that reduces the level of flutter, when the unbalanced positions of the left and right front wheels are in the same phase and the suspension system moves in the longitudinal direction of the vehicle, the flutter will be minimized and will move in the direction of the arrow shown in Figure 1. , no internal force acts on the rigid member 8, and the rigidity in the longitudinal direction is determined by the strut bar bush 7.
Since it is determined only by the stiffness of the vehicle, ride comfort will not be affected. Further, even if the vehicle is running at the same speed, flutter becomes maximum when the unbalanced positions of the left and right front wheels are in opposite phases, that is, when the longitudinal movement of the lower arm 5 is also in opposite phases. If the flutter level at the time of reverse phase is lowered, the flutter phenomenon will be reduced. The rigid member 8 increases the rigidity of the suspension system in the longitudinal direction, making it difficult for the lower arm 5 to move in the opposite direction. Therefore, the peak vehicle speed can be maintained higher than the normal vehicle speed range, and the flutter level at the normal vehicle speed can be reduced. Note that in this embodiment, the rigid member 8 is separated into the tubular member 13 and the rod-shaped member 14, but the rigid member 8 does not need to be separated.

Effects of the Invention As described above, according to the configuration of the present invention, the peak of the flutter level can be suppressed by simply connecting a rigid member to the body-mounted inner ends of the left and right lower arms that extend in opposite directions in the longitudinal direction of the vehicle. Even if the unbalanced positions of the left and right front wheels are in the opposite phase, the stiffness in the longitudinal direction can be increased to make it difficult for the lower arm to move and move the peak vehicle speed to a higher point than the normal range. The flutter level can be reduced.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention; FIG. 1 is a plan view schematically showing a front wheel suspension system for a vehicle, FIG. 2 is a front view of the rigid member, and FIG. 3 is a portion of the lower arm and the rigid member. FIG. 4 is a detailed sectional view, FIG. 4 is a bead diagram of the flutter, and FIG. 5 is a graph showing the relationship between the flutter level and vehicle speed when the rigid members are connected and separated. 5...Lower arm, 8...Rigid member, 13...
Tubular part of the rigid member, 14... Rod-shaped part of the rigid member,
15...stopper.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) The outer ends of the left and right lower arms support the wheels via knuckle arms, etc., and the body-mounted inner ends of the left and right lower arms extend in opposite directions of the longitudinal direction of the vehicle. A front wheel suspension system for a vehicle, characterized in that the extended end portions are connected by a rigid member. (2) Utility model registration claim 1, characterized in that the rigid member is connected and disconnected depending on the vehicle speed.
Front wheel suspension system for vehicles. (3) the rigid member is composed of a tubular part and a rod-shaped part,
A utility model for a vehicle according to claim 2, characterized in that the rod-shaped part is slidably inserted into the tubular part and a stopper is provided to stop both parts from sliding, and the actuation device of the stopper is controlled by a vehicle speed sensor. Front wheel suspension.