JP2007269139A - Strut type suspension system for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a strut type suspension system for a vehicle capable of improving the degree of freedom in setting a king pin shaft while avoiding increase of the number of parts and increase of cost. <P>SOLUTION: It is possible to reduce cost by eliminating division of a lower arm into two pieces and use of two pieces of expensive hinge joints while improving the setting freedom of the king pin shaft in comparison with a conventional general strut type suspension system as an upper part of a knuckle 12 and a first arm 19 of a damper 13 are pivotally supported by a piece of hinge joint 24 having an axis extending roughly in the vertical direction, a lower part of the knuckle 12 and a head end of an A type lower arm 11 are pivotally supported on a piece of ball joint 16 and both ends of a link 25 are respectively pivotally supported on an intermediate part of the lower arm 11 and a second arm 20 of the damper 13 by rubber bush joints 26, 27. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention includes a knuckle that rotatably supports a wheel, a single lower arm that connects the knuckle to a vehicle body, a damper that attenuates swinging of the lower arm, and a link that connects the damper to the lower arm. The present invention relates to a strut suspension device for a vehicle.

  As shown in FIG. 4, the kingpin shaft of the conventional general strut suspension device is determined by the connection point A of the damper 01 to the vehicle body and the connection point B of the lower arm 02 to the knuckle 03, so that the kingpin offset is If the driving force or braking force is applied to the wheel 04, the knuckle swings around the kingpin axis, and the driver may feel as if the steering wheel is removed. In order to suppress the kingpin offset to a small value, the kingpin tilt angle may be set large, but if this is done, a new problem that the force required for steering increases will occur.

Therefore, in the strut suspension device described in FIG. 1 of the following Patent Document 1, the lower arm is divided into first and second lower arms 24 and 26, and the respective lower arms 24 and 26 are knuckle 10 via ball joints 32 and 38, respectively. The upper part of the knuckle 10 is pivotally supported by a shock absorber (damper) 14 via a ball joint 16, and both ends of the link 42 are hinged joints 40 and 44 to the first lower arm 24 and the shock absorber 12, respectively. The kingpin offset is reduced without increasing the kingpin tilt angle.
Japanese Patent No. 3200854

  By the way, what is described in the above-mentioned patent document 1 is that the lower arm is used to absorb the deviation between the trajectory of the lower end of the shock absorber 12 and the trajectory where the tips of the first and second lower arms 24 and 26 swing up and down. Needs to be divided into first and second lower arms 24 and 26, and there is a problem that an integrated lower arm (A arm) cannot be employed.

  If a single A arm is adopted instead of the first and second lower arms 24 and 26 and the A arm and the knuckle 10 are pivotally supported by one ball joint, the hinge joints 40 and 44 at both ends of the link 42 are used. Since the suspension device cannot be stroked, it is necessary to replace the two hinge joints 40 and 44 with ball joints in order to allow the suspension device to stroke. However, if the joints at both ends of the link 42 are constituted by ball joints, the knuckle 10 cannot be supported in the caster angle direction, and the knuckle 10 falls in the caster angle direction when the vehicle is accelerated or braked.

  For this reason, the one described in Patent Document 1 requires that the lower arm be divided into first and second lower arms 24 and 26, and the joints at both ends of the link 42 are compared with ball joints or rubber bush joints. And expensive hinge joints 40 and 44, and there is a problem of increasing the number of parts and cost.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to increase the degree of freedom in setting a kingpin shaft while avoiding an increase in the number of parts and an increase in cost in a strut suspension device.

  In order to achieve the above object, according to the first aspect of the present invention, a knuckle that rotatably supports a wheel, a single lower arm that connects the knuckle to a vehicle body, and a swing of the lower arm are attenuated. In a vehicle strut suspension device comprising a damper and a link connecting the damper to the lower arm, the knuckle and the damper are pivotally supported by a single hinge joint having an axis extending in a generally vertical direction. A strut suspension device for a vehicle is proposed in which the lower arm is pivotally supported by a single ball joint, and both ends of the link are pivotally supported by the lower arm and the damper, respectively.

  According to the structure of claim 1, the knuckle and the damper are pivotally supported by a single hinge joint having an axis extending in the vertical direction, the knuckle and the lower arm are pivotally supported by a single ball joint, and both ends of the link are respectively connected. Since it is pivotally supported by the lower arm and damper, the lower arm can be divided into two parts or two expensive hinge joints can be used while making it possible to increase the degree of freedom of setting the kingpin shaft compared to conventional strut suspension devices. Cost can be reduced.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

  1 to 3 show an embodiment of the present invention, FIG. 1 is a perspective view of a strut type suspension device, FIG. 2 is an explanatory diagram showing an action at the time of bump, and FIG. 2 shows a state at the time of rebound. It is an operation explanatory view.

  As shown in FIG. 1, a strut suspension device S includes a single lower arm 11 formed of a so-called A-type arm, a knuckle 12 that rotatably supports a wheel W, and a damper 13 that buffers vertical movement of the knuckle 12. With. The base end portion of the lower arm 11 that is bifurcated is pivotally supported by the vehicle body via rubber bush joints 14 and 15, and the tip end portion that extends outward from the base end portion in the vehicle width direction is provided below the knuckle 12 via a ball joint 16. To be supported.

  The damper 13 extends from the middle of the cylinder 17, the piston rod 18 protruding and retracting from the upper end of the cylinder 17, the first arm 19 projecting outward in the vehicle width direction from the lower end of the cylinder 17, and obliquely rearward and downward. A second arm 20, a spring seat 21 fixed to the upper end of the cylinder 17, and a vehicle body fixing portion 22 provided at the upper end of the piston rod 18 are provided. The upper surface of the spring seat 21 and the lower surface of the vehicle body fixing portion 22 are provided. A coil spring 23 is disposed therebetween.

  The upper part of the knuckle 12 and the tip of the first arm 19 of the damper 13 are pivotally supported by a hinge joint 24 having a generally vertical axis. Further, the front end of the link 25 arranged in the longitudinal direction of the vehicle body is pivotally supported by a middle portion in the vehicle width direction on the upper surface of the lower arm 11 via a rubber bush joint 26, and the rear end of the link 25 is a damper via a rubber bush joint 27. It is pivotally supported by the lower ends of the 13 second arms 20.

  With this configuration, both ends of the link 25 are connected to the lower arm 11 and the second arm 20 of the damper 13 with respect to the axis of relative rotation without dividing the lower arm into two members as in the strut suspension device described in the above cited reference 1. Is not supported by a hinge joint but is supported by rubber bush joints 26 and 27 that can be rotated in any direction by deformation of the rubber bush. Therefore, as shown in FIGS. Even if the bump and rebound, the free vertical swing of the lower arm 11 is not hindered.

  Further, when a load in the longitudinal direction of the vehicle body is input from the wheel W to the knuckle 12 during acceleration or braking of the vehicle, the ball joint 16 and the rubber bush joints 26 and 27 that pivot the lower part of the knuckle 12 to the tip of the lower arm 11 are not used. Although the knuckle 12 is tilted in the longitudinal direction of the vehicle body and the caster rigidity cannot be secured, in this embodiment, the upper portion of the knuckle 12 is pivotally supported by the first arm 19 of the damper 13 by the hinge joint 24 having a generally vertical axis. As a result, the knuckle 12 can be prevented from collapsing in the longitudinal direction of the vehicle body and caster rigidity can be ensured.

  Thus, according to the present embodiment, the strut suspension device (described in the above cited reference 1) is reduced while increasing the degree of freedom of setting the kingpin shaft and reducing the kingpin offset as compared with a general strut suspension device. Hereinafter, the structure of the lower arm and the joint can be simplified as compared with the conventional example), and the cost can be reduced.

  That is, in the conventional example, since the lower arm is divided into the first and second lower arms 24 and 26, not only the number of parts of the lower arm itself is increased, but also two lower arms are pivotally supported on the knuckle 10. Ball joints 32 and 38 are required. On the other hand, in the present embodiment, the single lower arm 11 only needs to be pivotally supported by the knuckle 12 with the single ball joint 16, so the number of ball joints can be reduced.

  Further, since the hinge joint is more expensive than the ball joint or the rubber bush joint, it is desirable to reduce the number thereof as much as possible. In this regard, the conventional example includes two hinge joints 40 and 44 at both ends of the link 42, whereas in the present embodiment, only one hinge joint 24 is provided above the knuckle 12. The cost can be reduced by reducing the number of expensive hinge joints.

  In summary, the number of lower arms is two in the conventional example, but is reduced to one in the present embodiment, and the total number of joints is five in the conventional example. In the present embodiment, the number of hinge joints can be reduced to one, whereas the number of hinge joints is two in the conventional example.

  Therefore, in the conventional general strut suspension device shown in FIG. 4, the connection point A of the damper 01 to the vehicle body cannot be moved outward in the vehicle width direction because the damper 01 interferes with the wheel 04. Further, since the connecting point B of the lower arm 02 to the knuckle 03 interferes with the brake disc supported by the knuckle 03 and cannot be moved outward in the vehicle width direction, it is difficult to reduce the kingpin offset.

  On the other hand, in the present embodiment, the kingpin axis is determined by the position of the ball joint 16 (connection point B in FIG. 4) and the position of the hinge joint 24, and the position of the hinge joint 24 is the position of the vehicle body fixing portion 22 at the upper end of the damper 13. Since the degree of freedom is higher than the position (the connection point A in FIG. 4), the degree of freedom of setting the kingpin axis can be increased and the kingpin offset can be reduced.

  The embodiments of the present invention have been described above, but various design changes can be made without departing from the scope of the present invention.

  For example, in the embodiment, both ends of the link 25 are pivotally supported by the rubber bush joints 26 and 27, but it may be pivotally supported by a ball joint.

Perspective view of strut suspension device Action explanation diagram showing the state at the time of bump Action explanation diagram showing the state at the time of rebound A diagram showing a conventional strut suspension device

Explanation of symbols

11 Lower arm 12 Knuckle 13 Damper 16 Ball joint 24 Hinge joint 25 Link W Wheel

Claims (1)

A knuckle (12) for rotatably supporting the wheel (W);
A single lower arm (11) connecting the knuckle (12) to the vehicle body;
A damper (13) for damping the swing of the lower arm (11);
A link (25) connecting the damper (13) to the lower arm (11);
In a vehicle strut suspension device comprising:
Pivoting the knuckle (12) and the damper (13) with a single hinge joint (24) having an axis extending generally in the vertical direction;
The knuckle (12) and the lower arm (11) are pivotally supported by a single ball joint (16),
A strut suspension device for a vehicle, wherein both ends of the link (25) are pivotally supported by the lower arm (11) and the damper (13), respectively.

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