JP4053014B2 - Suspension device - Google Patents

Description

  The present invention includes a knuckle formed by fastening front and rear portions of a lower arm support bracket with front and rear bolts to a front fastening portion and a rear fastening portion provided at a lower portion of a knuckle body, and an inner end in a vehicle width direction is connected to a vehicle body. The present invention also relates to a suspension device including a lower arm whose outer end in the vehicle width direction is connected to a lower arm support bracket.

  6 and 7 show a conventional suspension device. The knuckle 01 has a lower arm support bracket 03 connected to the lower end of the knuckle main body 02 by two bolts 04 and 05, and an upper end of the knuckle main body 01. The outer end in the vehicle width direction of the arm 06 is connected via a ball joint 08, and the outer end in the vehicle width direction of the lower arm 07 is connected to the lower arm support bracket 03 via a ball joint 09. A pair of fastening portions 02a and 02b projecting downward is integrally formed at the front and rear ends of the lower portion of the knuckle body 02, and the front and rear ends of the lower arm support bracket 03 are bolts 04 on the fastening surfaces of these fastening portions 02a and 02b. , 05.

  By the way, in the conventional suspension device, when the load F directed toward the rear of the vehicle body is not acting on the wheel W, the straight line L connecting the two bolts 04 and 05 that fasten the lower arm support bracket 03 to the lower end of the knuckle body 02 is the vehicle body. Since they are aligned in the front-rear direction, when the wheel W gets over the unevenness of the road surface or the wheel W is braked and a load F is applied toward the rear of the vehicle body, the straight line L is moved to the position L ′ together with the wheel W. There was a tendency to toe out.

  As a result, the front-side bolt 04 is displaced outward in the vehicle width direction from the straight line L along the longitudinal direction of the vehicle body, and the rear-side bolt 05 is displaced inward in the vehicle width direction from the straight line L along the longitudinal direction of the vehicle body. A large moment with the displacement as a moment arm acts on the fastening portions 02a and 02b of the main body 02, and measures such as thickening the front and rear bolts 04 and 05 are necessary, which causes a weight increase. It was.

  The present invention has been made in view of the above circumstances, and an object thereof is to reduce a load applied to bolts before and after fastening a lower arm support bracket to a lower portion of a knuckle body.

In order to achieve the above object, according to the first aspect of the present invention, the front and rear portions of the lower arm support bracket are fastened with the front and rear bolts to the front fastening portion and the rear fastening portion provided at the lower portion of the knuckle body. The lower arm includes a knuckle configured as described above and a single lower arm whose inner end in the vehicle width direction is connected to the vehicle body and whose outer end in the vehicle width direction is pivotally connected to the lower arm support bracket at one location. And the lower arm support bracket are located on a straight line connecting the front bolt and the rear bolt in a plan view, and the straight line is toe-in in a normal state, and the knuckle moves to the rear of the vehicle body. A suspension device is proposed in which the toe-in angle is reduced when a load is applied.

  According to the configuration of claim 1, the straight line connecting the bolts before and after fastening the lower arm support bracket to the lower part of the knuckle body is toe-in at the normal time when the load to the rear of the vehicle body is not applied to the knuckle. When a load on the rear of the vehicle body acts on the knuckle due to overcoming road surface irregularities or braking of the wheel, the toe-in angle of the straight line decreases due to the wheel toe-out with the load. As a result, the front and rear bolts are aligned in the longitudinal direction of the vehicle body, and the displacement in the vehicle width direction is reduced, and the load applied to the rear of the vehicle body is reduced and the moment to try to twist the knuckle is reduced, thereby reducing the load applied to the bolts. Durability can be increased.

  DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below based on examples of the present invention shown in the accompanying drawings.

  1 to 4 show a first embodiment of the present invention. FIG. 1 is a perspective view of a double wishbone suspension of a left rear wheel, FIG. 2 is a view in the direction of the arrow 2 in FIG. FIG. 4 is an enlarged cross-sectional view of the main part of FIG. 3.

As shown in FIGS. 1 to 3, the double wishbone type suspension device S includes a knuckle 13 supported by a vehicle body by an upper arm 11 and a single lower arm 12. The knuckle 13 includes a knuckle body 14 made of light alloy forging, and a lower arm support bracket 15 made of an iron-based material fastened to the lower part thereof. The knuckle body 14 includes an axle support portion 14a that rotatably supports the axle of the wheel W, and an upper arm support portion 14b that extends upward from the axle support portion 14a, and a ball joint at the upper end of the upper arm support portion 14b. 16, the outer end of the upper arm 11 in the vehicle width direction is pivotally supported.

  As is apparent from FIG. 4, a pair of front and rear fastening portions 14c and 14d protrude downward from the lower front and rear ends of the axle support portion 14a of the knuckle body 14, and a recess recessed upwardly between the two fastening portions 14c and 14d. 14e is formed. The lower arm support bracket 15 includes front and rear end mounting portions 15a and 15b, a central lower arm support portion 15c, and a pair of inclined connection portions 15d and 15e that connect the mounting portions 15a and 15b and the lower arm support portion 15c. The front mounting portion 15a is fixed to the fastening surface of the front fastening portion 14c with the bolt 17 and the nut 18, and the rear mounting portion 15b is fixed to the fastening surface of the rear fastening portion 14d with the bolt 19. The lower arm support portion 15c of the lower arm support bracket 15 is positioned lower than the mounting portions 15a and 15b, and the lower arm 12 is formed in a space 20 formed between the recess 14e of the knuckle body 14 and the lower arm support portion 15c of the lower arm support bracket 15. The vehicle width direction outer end of is arranged.

A ball joint 21 that pivotally supports the lower end of the lower arm 12 in the vehicle width direction at one position on the lower arm support bracket 15 is connected to a spherical head portion 22a, a conical shaft portion 22b connected to the head portion 22a, and a shaft portion 22b. A ball stud 22 composed of a male screw portion 22c is provided. The shaft portion 22b of the ball stud 22 passes through the attachment hole 15f provided in the lower arm support portion 15c of the lower arm support bracket 15 from the top to the bottom, and the nut 23 is screwed into the male screw portion 22c protruding downward from the lower arm support portion 15c. It is fixed by that. The ball joint 21 includes a cup-shaped housing 12 a provided at the end of the lower arm 12. A synthetic resin bearing 25 slidably contacting the head 22a of the ball stud 22 is housed on the inner peripheral surface of the housing 12a, and is held by a retainer 26 fixed so as to cover the opening of the housing 12a. A boot 27 is mounted between the opening of the housing 12a and the lower arm support portion 15c of the lower arm support bracket 15 so that dust and the like do not enter the head 22a of the ball stud 22 and the sliding surface of the bearing 25.

As is clear from FIG. 2, the straight line L connecting the bolts 17 and 19 before and after the lower arm support bracket 15 is fastened to the knuckle body 14 is toe-in when the wheel W is not subjected to the load F to the rear of the vehicle body. ing. That is, the straight line L is inclined toward the inner side in the vehicle width direction on the vehicle body front side. Therefore, when the wheel W gets over the unevenness of the road surface or the wheel W is braked and a load F directed toward the rear of the vehicle body is applied , the pivot connection portion between the lower arm 12 and the lower arm support bracket 15 is seen in plan view. Since the king focus rail of the suspension device S is located on the straight line L and is on the inner side in the vehicle width direction from the ground contact point of the wheel W, the wheel W and the knuckle 13 are swung in the toe-out direction by the load, and the front and rear bolts The toe-in angle of the straight line L connecting 17 and 19 decreases toward zero (see the straight line L ′).

Thus, you can get over the wheel W is of the road surface irregularities, even if the wheels W is or is braked acts backward load F to the knuckle 13, the straight line L connecting the front and rear of the bolt 17 and 19 back and forth in the toe-out Since the bolts 17 and 19 are aligned substantially in the front-rear direction of the vehicle body, the torsional moment applied to the front and rear fastening portions 14c and 14d by the load F is suppressed, and the load acting on the bolts 17 and 19 is reduced, resulting in durability. In addition, the use of small-diameter bolts 17 and 19 is enabled, which contributes to weight reduction.

  Next, a second embodiment of the present invention will be described with reference to FIG.

  In the first embodiment, the ball stud 22 of the ball joint 21 is fixed to the lower arm support bracket 15, but in the second embodiment, the housing 24 of the ball joint 21 is fixed to the lower arm support bracket 15. That is, the housing 24 of the ball joint 21 is press-fitted from the top to the bottom into the mounting hole 15 f formed in the lower arm support portion 15 c of the lower arm support bracket 15. The outer end in the vehicle width direction of the lower arm 12 is fitted to a ball stud 22 protruding downward from the housing 24 and fastened by a nut 28.

  Also in this second embodiment, the straight line L connecting the bolts 17 and 19 before and after the lower arm support bracket 15 is fastened to the knuckle body 14 is toe-in at the normal time when the load F is not applied to the wheel W. When the load F directed toward the rear of the vehicle body acts on the wheel W, the toe-in angle of the straight line L connecting the front and rear bolts 17 and 19 decreases toward zero.

  Therefore, the second embodiment can achieve the same operation and effect as the first embodiment described above.

  Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various design changes can be made without departing from the present invention described in the claims. It is.

  For example, in the embodiment, the double wishbone type suspension apparatus S is illustrated, but the present invention can be applied to any other type of suspension apparatus.

  In the embodiment, the front bolt 17 is a stud bolt and the rear bolt 19 is a normal bolt, but the type of the bolt can be arbitrarily selected.

  In the embodiment, the front and rear bolts 17 and 19 have the same thickness, but it is not always necessary.

Perspective view of the left wish wheel double wishbone suspension 2 direction view of FIG. 3 direction enlarged arrow view of FIG. 3 is an enlarged cross-sectional view of the main part of FIG. The figure corresponding to the said FIG. 4 based on 2nd Example. FIG. 2 is a diagram corresponding to FIG. 7 direction arrow view of FIG.

Explanation of symbols

12 Lower arm 13 Knuckle 14 Knuckle body 14c Fastening portion 14d Fastening portion 15 Lower arm support bracket 17 Bolt 19 Bolt F Load L to the rear of the vehicle body Straight line connecting the front fastening portion and the rear fastening portion

Claims (1)

The front and rear portions of the lower arm support bracket (15) are fastened with the front and rear bolts (17, 19) to the front fastening portion (14c) and the rear fastening portion (14d) provided at the lower part of the knuckle body (14). And a single lower arm (12) whose inner end in the vehicle width direction is connected to the vehicle body and whose outer end in the vehicle width direction is pivotally connected to the lower arm support bracket (15) at one place . In the suspension device,
The pivot connection portion between the lower arm (12) and the lower arm support bracket (15) is located on a straight line (L) connecting the front bolt (17) and the rear bolt (19) in plan view . The suspension device is characterized in that the straight line (L) is toe-in at a normal time, and a toe-in angle is reduced when a load (F) to the rear of the vehicle body acts on the knuckle (13).

Images