Automobile suspension system

Abstract

To provide a suspension device of an automobile capable of suppressing displacement of an imaginary king pin axis by bringing the imaginary king pin axis and connection portions with a wheel support of respective arms on the upper side of a vehicle close to each other.SOLUTION: A suspension device of an automobile includes an imaginary king pin axis IK which vertically connects an intersection point P1 on imaginary extension lines of an upper arm 4 and a leading arm 5 and an intersection point P2 on imaginary extension lines of a trailing arm 6 and a lower arm 7. The upper arm 4 and the leading arm 5 are connected to a wheel support 10 via pivot portions 46 and 54. Vertically above the intersection P2 on the respective imaginary extension lines of the trailing arm 6 and the lower arm 7 in a side view, the pivot portion 46 of the upper arm 4 and the pivot portion 54 of the leading arm 5 are arranged so as to overlap each other in a longitudinal direction of a vehicle in a plan view, as well as, overlap each other in a vehicle vertical direction and a vehicle width direction in a front view.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present invention relates to a suspension device for an automobile, and more particularly to a multi-link rear wheel suspension consisting of five I-links. [Background technology]

[0002] Conventionally, a multi-link suspension is known that has five I-links (hereinafter referred to as "arms"), with the vehicle body end of each arm connected to the vehicle body and the wheel end of each arm connected to a wheel support (hub carrier) that supports the wheel. This type of multi-link suspension with five arms has high performance potential because it is possible to arrange each arm so that it optimally constrains the five degrees of freedom of movement, excluding the up and down stroke of the rear wheels, according to the requirements for each. Each arm is basically connected to the vehicle body and wheel support via an elastic bush, and the rigidity of each elastic bush is set taking into consideration the driving stability and vibration isolation performance.

[0003] In such multi-link suspensions, there is a virtual kingpin axis that connects the intersection of the virtual extensions of the two upper arms with the intersection of the virtual extensions of the two lower arms in the vertical direction of the vehicle, and it is known that the positional relationship between the contact point of this virtual kingpin axis and the center of the wheel contact patch affects the wheel behavior (for example, Patent Documents 1 and 2). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] International Publication No. 2003 / 008212 [Patent Document 2] DE 102010030292 Summary of the Invention [Problem to be solved by the invention]

[0005] However, when each arm is displaced by an external force applied to the wheel (rear wheel), this imaginary kingpin axis is displaced from its ideal position, which may cause an unexpected change in the toe angle of the rear wheel, making it impossible to obtain stable rear wheel behavior. Also, the longer the imaginary extension distance from the connection position of each arm to the wheel support to the imaginary kingpin axis, the greater the displacement of the imaginary kingpin axis when each link is displaced.

[0006] Therefore, the present invention has been made to solve the above-mentioned problems, and has an object to provide an automobile suspension device that can suppress displacement of the imaginary kingpin axis by bringing the imaginary kingpin axis close to the connection portions of the arms on the upper side of the vehicle with the wheel supports. [Means for solving the problem]

[0007] In order to solve the above-mentioned problems, the present invention provides a wheel support having an opening formed in the center for passing an axle therethrough, an upper arm extending from a connecting portion on the vehicle body side toward the rear of the vehicle and connected to the wheel support above the axle, a leading arm extending from the connecting portion on the vehicle body side toward the front of the vehicle and connected to the wheel support above the axle, a trailing arm extending from the connecting portion on the vehicle body side toward the rear of the vehicle and connected to the wheel support below the axle, a lower arm extending from the connecting portion on the vehicle body side toward the front of the vehicle and connected to the wheel support below the axle, and a lower arm extending from the connecting portion on the vehicle body side in the vehicle width direction and connected to the wheel support below the axle. and a toe control arm connected to a wheel support, the toe control arm having a toe support and a toe control arm connected to the wheel support, the toe control arm having a toe support and a toe control arm connected to the wheel support, the toe control arm having a toe support and a toe control arm connected to the wheel support, the toe control arm having a toe support and a toe control arm connected to the wheel support, the toe control arm having a toe support and a toe control arm connected to the wheel support, the toe control arm having a toe support and a toe control arm connected to the wheel support, the toe control arm having a toe support and a toe control arm connected to the wheel support, A recess is formed in a lower edge portion of the leading arm near the pivot portion, and the pivot portion of the upper arm is disposed in the recess in the lower edge portion of the leading arm in a front view. , which is its characteristic.

[0008] According to the present invention configured as described above, there is a virtual kingpin axis vertically connecting an intersection of the virtual extension lines of the upper arm and the leading arm and an intersection of the virtual extension lines of the trailing arm and the lower arm, the upper arm and the leading arm are connected to the wheel support via a pivot portion, and the pivot portion of the upper arm and the pivot portion of the leading arm are arranged to overlap in the vehicle fore-and-aft direction in plan view and to overlap in the vehicle up-and-down direction and the vehicle width direction in front view vertically above the intersection of the virtual extension lines of the trailing arm and the lower arm in side view, so that the virtual kingpin axis can be made to extend in the vertical direction in side view and can be brought close to the connection portion of the upper arm and the leading arm with the wheel support, thereby suppressing displacement of the virtual kingpin axis. Furthermore, according to the present invention configured in this manner, a concave portion is formed in the lower edge portion near the pivot portion of the leading arm, and in front view, the pivot portion of the upper arm is positioned in the concave portion of the lower edge portion of the leading arm, so that the connection portion of the upper arm with the wheel support and the connection portion of the leading arm with the wheel support can be positioned close to each other in both the up, down, left and right directions when viewed from the front.

[0009] Also in the present invention, the pivot portion of the upper arm is preferably disposed at an angle of approximately 45 degrees downward in the vehicle vertical direction and inward in the vehicle width direction with respect to the pivot portion of the leading arm when viewed from the front. According to the present invention configured in this manner, the connection portions of the upper arm and the leading arm with the wheel support can be brought close to each other in both the up, down, left and right directions when viewed from the front, which makes it possible to effectively bring the imaginary kingpin axis close to those connection portions.

[0010] In addition, in the present invention, preferably, a vertical wall portion protruding inward in the vehicle width direction is formed on the portion of the wheel support forward of the axle, and the pivot portion of the upper arm and the pivot portion of the leading arm are both provided on the vertical wall portion of the wheel support. According to the present invention configured in this manner, the pivot portions of the upper arm and the trailing arm are integrally provided on the vertical wall portion of the wheel support, thereby ensuring the supporting rigidity of the upper arm and the trailing arm.

[0012] In addition, in the present invention, preferably, the pivot portion of the upper arm and the pivot portion of the leading arm each include a bush provided at the wheel support side end of each arm and a bush housing formed in the wheel support, and the bush and bush housing at the pivot portion of the upper arm and the bush and bush housing at the pivot portion of the leading arm are arranged so as to overlap in the vertical direction and width direction of the vehicle when viewed from the front, or the bush housings at those pivot portions are arranged so as to overlap in the vertical direction and width direction of the vehicle when viewed from the front. According to the present invention configured in this manner, the connection portion of the upper arm with the wheel support and the connection portion of the leading arm with the wheel support can be more reliably positioned close to each other in both the up, down, left and right directions when viewed from the front. Effect of the Invention

[0013] According to the automobile suspension device of the present invention, the imaginary kingpin axis can be brought into close proximity with the connection portions between the wheel supports of each arm on the upper side of the vehicle, thereby suppressing displacement of the imaginary kingpin axis. [Brief description of the drawings]

[0014] [Figure 1] 1 is a perspective view of a rear suspension assembly of an automobile to which an automobile suspension device according to an embodiment of the present invention is applied; [Diagram 2] FIG. 2 is a top view of the rear suspension assembly shown in FIG. [Diagram 3] FIG. 2 is a rear view of the rear suspension assembly shown in FIG. [Figure 4] FIG. 2 is a top view of the rear suspension on the left side of the vehicle according to the present embodiment. [Diagram 5] FIG. 5 is a left side view of the rear suspension of FIG. 4. [Figure 6] FIG. 5 is a front view of the rear suspension of FIG. [Figure 7]5 is a view of the rear suspension of FIG. 4 as seen from the inside in the vehicle width direction. [Figure 8] FIG. 5 is a front view showing the peripheral structure of a wheel support of the rear suspension of FIG. 4. [Figure 9] FIG. 5 is a rear view showing the wheel support peripheral structure of the rear suspension of FIG. 4. [Figure 10] 5 is a top view for explaining the positional relationship of pivot portions in the wheel support of the upper arm and the trailing arm of the rear suspension in FIG. 4. [Figure 11] FIG. 5 is a side view for explaining the positional relationship of pivot portions in wheel supports of an upper arm and a trailing arm of the rear suspension in FIG. 4, with the wheel supports not shown. [Figure 12] FIG. 5 is a front view for explaining the positional relationship of pivot portions in wheel supports of an upper arm and a trailing arm of the rear suspension in FIG. 4, with the wheel supports not shown. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an automobile suspension device according to an embodiment of the present invention will be described with reference to the accompanying drawings.

[0016] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. First, the overall configuration of an automobile suspension device according to an embodiment of the present invention will be described with reference to Figures 1 to 3. Figures 1 to 3 show an embodiment in which an automobile rear wheel suspension device 1 (hereinafter simply referred to as a rear suspension) according to an embodiment of the present invention is applied to the rear wheels on both the left and right sides of an automobile, Figure 1 is a perspective view of an automobile rear suspension assembly to which the automobile suspension device according to the embodiment of the present invention is applied, Figure 2 is a top view of the rear suspension assembly shown in Figure 1, and Figure 3 is a rear view of the rear suspension assembly shown in Figure 1. The automobile (vehicle) of this embodiment is a rear-wheel drive vehicle having an engine mounted in an engine room at the front of the vehicle body (not shown), a differential disposed at the rear of the vehicle body, and rear wheels 2 driven by an axle (not shown). As shown in FIGS. 1 to 3, a rear suspension assembly of a rear wheel suspension device 1 includes a pair of left and right rear suspensions 1 and a subframe 3.

[0017] First, the general configuration of the rear suspension 1 will be described. The rear suspension 1 of this embodiment is of a multi-link type in which a wheel support (support member, hub carrier) 10 of the rear wheel 2 is connected to the vehicle body in a strokeable manner by five independent I-links 4 to 8. The suspension device 1 includes a front upper link (hereinafter referred to as "upper arm") 4 and a rear leading link (hereinafter referred to as "leading arm") 5 that virtually constitute an upper arm, a front trailing link (hereinafter referred to as "trailing arm") 6 and a rear lower link (hereinafter referred to as "lower arm") 7 that virtually constitute a lower arm, and a toe control link (hereinafter referred to as "toe control arm") 8 that regulates the rotational displacement of the rear wheel 2 around a virtual kingpin axis IK (see FIG. 5) described later. The upper arm 4, the leading arm 5, the trailing arm 6, and the lower arm 7 each swing up and down around a connecting portion (44, 52, 60, 68) on the vehicle body side, so that the wheel support 10 and the rear wheel 2 stroke up and down along a predetermined trajectory.

[0018] A shock absorber 16 is provided that includes a coil spring 12 and a damper 14 to allow such a stroke of the rear wheel 2 while at the same time applying a predetermined biasing force and damping force. The shock absorber 16 has a vertically long cylindrical shape in which the coil spring 12 and the damper 14 are arranged approximately coaxially, and its upper end is attached to the vehicle body. The lower end of the shock absorber 16 (the lower end of the damper 14) is pivotally attached to the lower arm 7. Further, a stabilizer bar 18 is rotatably attached to the suspension device 1 so as to extend so as to connect the left and right lower arms 7 together.

[0019] Next, a schematic configuration of the subframe 3 will be described. The subframe 3 is formed mainly by combining four steel plate components into a rectangular frame shape when viewed in a plane, and includes a front cross member 20 and a rear cross member 22 that extend in the vehicle width direction, and a pair of side cross members 24, 26 that extend in the fore-and-aft direction on both the left and right sides of the vehicle body so as to connect the left and right ends of the front and rear cross members together.

[0020] The front cross member 20 extends linearly in the vehicle width direction when viewed from above the vehicle, and both ends 20a in the vehicle width direction are joined to the front ends of the left and right side cross members 24, 26, respectively. When viewed in the vehicle longitudinal direction, the front cross member 20 is formed in an arch shape that is curved overall so that its longitudinal center portion is located higher than both the left and right ends. Furthermore, at both left and right ends of the front cross member 20, mounting seats 28 for the upper arm 4 and mounting seats 30 for the trailing arm 6 are provided, respectively, in positions close to the joints 20a with the side cross members 24, 26 and above and below the side cross members 24, 26 (see Figures 4 to 6). The vehicle body side end of the upper arm 4 is connected to the mounting seats 28 on both the left and right sides, and the vehicle body side end of the trailing arm 6 is connected to the mounting seats 30 on both the left and right sides.With this configuration, the front cross member 20 is able to withstand the lateral force transmitted from the wheels 2 via the arms 4, 6.

[0021] The rear cross member 22 extends linearly in the vehicle width direction when viewed from above the vehicle, and both ends 22a in the vehicle width direction are joined to the rear ends of the left and right side cross members 24, 26, respectively. As shown in Fig. 3, the rear cross member 22 is formed in an arch shape that is curved overall so that its longitudinal center portion is located lower than both the left and right ends when viewed in the vehicle front-rear direction. At both left and right ends of the rear cross member 22, a mounting seat 32 for the leading arm 5 and a mounting seat 34 for the lower arm 7 are provided, respectively, in positions close to the joints 22a with the side cross members 24, 26 and above and below the side cross members 24, 26 (see Figs. 4 and 5). The vehicle body side end of the leading arm 5 is connected to each of the mounting seats 32 on the left and right sides, and the vehicle body side end of the lower arm 7 is connected to each of the mounting seats 34 on the left and right sides.With this configuration, the rear cross member 22 receives the lateral force transmitted from the wheels 2 via each arm 5, 7.

[0022] Further, in top view, the rear cross member 22 is provided with mounting seats 36 for the toe control arms 8 on the inside in the vehicle width direction of each of the side cross members 24, 26 and on the rear side of the rear cross member 22. The vehicle body side ends of the toe control arms 8 are connected to the mounting seats 36 on both the left and right sides, respectively.

[0023] The left and right side cross members 24, 26 are each curved so that their longitudinal center portions are located inward in the vehicle width direction compared to both ends when viewed from above the vehicle, and extend obliquely downward toward the front of the vehicle from their rear ends to their front ends when viewed from the side (see FIG. 5). The above-mentioned mounting seats 28, 30 are provided in the front portions of these side cross members 24, 26, and the above-mentioned mounting seats 32, 34 are provided in the rear portions thereof.

[0024] Additionally, the side cross members 24, 26 are provided with elastic mounts 38, 40 for elastically supporting the entire subframe 3 on the vehicle body, and these elastic mounts 38, 40 are provided at a total of four locations, at the front and rear ends of each side cross member 24, 26. Each elastic mount 38, 40 has a cylindrical shape with an axis in the up-down direction, and is attached to a recess formed in each side cross member 24, 26. In each side cross member 24, 26, each elastic mount 38, 40 is disposed so that, when viewed from above the vehicle, a straight line connecting the elastic mount 38 at the front end and the elastic mount 40 at the rear end is substantially parallel to the center line CL (shown only in FIG. 2) in the fore-and-aft direction of the vehicle body.

[0025] Each elastic mount 38, 40 is formed with a predetermined gap called a "sugiri," and each elastic mount 38, 40 is formed so that its hardness (a characteristic indicated by the magnitude of the load (N) that produces a predetermined amount of deflection (mm)) differs in the front-to-back direction and the left-to-right direction relative to its axis. In this embodiment, each of the elastic mounts 38, 40 is attached to the side cross members 24, 26 so as to be oriented such that its stiffness in the vehicle width direction is greater than its stiffness in the vehicle front-rear direction. In addition, in this embodiment, the elastic mounts 38, 40 have different hardnesses, and the hardness of the elastic mount 38 at the front end in the fore-and-aft direction of the vehicle is set to be smaller (softer) than the hardness of the elastic mount 40 at the rear end in the fore-and-aft direction of the vehicle.

[0026] Next, the arrangement of the arms 4-8 of the rear suspension device 1 on the left side of the vehicle will be described with reference to Fig. 4 to Fig. 7. Fig. 4 is a top view of the rear suspension on the left side of the vehicle according to this embodiment, Fig. 5 is a left side view of the rear suspension in Fig. 4, Fig. 6 is a front view of the rear suspension in Fig. 4, and Fig. 7 is a view of the rear suspension in Fig. 4 as seen from the inside in the vehicle width direction. The rear suspension device 1 on the right side of the vehicle has the same configuration as the rear suspension 1 on the left side of the vehicle, so its description will be omitted below.

[0027] 4 to 6, the upper arm 4 has an end portion on the vehicle body side connected to the above-mentioned mounting seat 28 via an elastic bush (a rubber bush, hereinafter referred to as "bush") 42. The upper arm 4 extends with a rearward inclination so as to be gradually positioned rearward from a connecting portion 44 on the vehicle body side toward the outside in the vehicle width direction when viewed from above the vehicle. At a connecting portion 46 on the wheel 2 side, the end portion of the upper arm 4 on the wheel 2 side is connected to the wheel support 10 via a bush 48.

[0028] Next, the leading arm 5 has its end on the vehicle body side connected to the above-mentioned mounting seat 32 via a bush 50. When viewed from above the vehicle, the leading arm 5 extends with a forward inclination so as to be gradually positioned forward from the connecting part 52 on the vehicle body side toward the outside in the vehicle width direction. At the connecting part 54 on the wheel 2 side, the end of the leading arm 5 on the wheel 2 side is connected to the wheel support 10 via a bush 56.

[0029] In this manner, the two upper arms 4, 5 are disposed so as to approach each other toward the outside of the vehicle body when viewed from above the vehicle. In this embodiment, pillow ball joints are used for the bushes 42, 50 on the vehicle body side and the bushes 48, 56 on the wheel 2 side.

[0030] Next, the end of the trailing arm 6 on the vehicle body side is connected to the above-mentioned mounting seat 30 via a bush 58. When viewed from above the vehicle, the trailing arm 6 extends at a rearward inclination so that it is gradually positioned further rearward from a connecting part 60 on the vehicle body side toward the outside in the vehicle width direction. At a connecting part 62 on the wheel 2 side, the end of the trailing arm 6 on the wheel 2 side is connected to the wheel support 10 via a bush 64.

[0031] Next, the lower arm 7 has an end portion on the vehicle body side connected to the above-mentioned mounting seat 34 via a bush 66. The lower arm 7 extends with a forward inclination so as to be gradually positioned forward from a connecting portion 68 on the vehicle body side toward the outside in the vehicle width direction when viewed from above the vehicle. At a connecting portion 70 on the wheel 2 side, the end portion of the trailing arm 6 on the wheel 2 side is connected to the wheel support 10 via a bush 72.

[0032] In this way, the two lower arms 6, 7 are arranged so as to approach each other outward in the vehicle width direction when viewed from above the vehicle, and mainly due to this arrangement, a geometric toe-in is imparted to the rear wheels 2 as they are displaced toward the rear of the vehicle (longitudinal force compliance steer). That is, for example, when a braking force from the road surface acts on the rear wheels 2 during braking (when a force acting toward the rear of the vehicle is applied), the two lower arms 6, 7 are slightly pivotally displaced about the ends on the vehicle body side due to the bending of the bushes 56, 64, respectively, and as a result, the alignment of the rear wheels 2 changes to the toe-in direction. Furthermore, when a lateral force is applied to the wheel 2 during turning, the bushes 56, 64 of the lower arms 6, 7 are primarily deflected, causing the wheel 2 to change to a toe-in direction (lateral force compliance steer). In this embodiment, pillow ball joints are used for the bushes 58, 66 on the vehicle body side and the bushes 64, 72 on the wheel 2 side.

[0033] Next, the toe control arm 8 has its end on the vehicle body side connected to the above-mentioned mounting seat 36 via a bush 74. When viewed from above the vehicle, the toe control arm 8 extends with a forward inclination so as to be gradually positioned forward from a connecting portion 76 on the vehicle body side toward the outside in the vehicle width direction. At a connecting portion 78 on the wheel 2 side, the end of the trailing arm 6 on the wheel 2 side is connected to the wheel support 10 via a bush 80. In this embodiment, a pillow ball joint is used for the bush 74 on the vehicle body side and the bush 80 on the wheel 2 side.

[0034] 4 to 6, a virtual kingpin axis IK is formed in the rear suspension 1, vertically connecting an intersection P1 between an imaginary extension line of the upper arm 4 and an imaginary extension line of the leading arm 5, and an intersection P2 between an imaginary extension line of the trailing arm 6 and an imaginary extension line of the lower arm 7. This imaginary kingpin axis is the instantaneous rotation center of the rear wheel 2 in the steering direction (toe direction).

[0035] Next, the configuration of the wheel support 10 and the mounting configuration of each arm will be described with reference to Figs. First, as shown in FIGS. 4 to 7, the wheel support 10 has a hub 82 attached to its center, and is formed with an opening 84 through which an axle (not shown) passes. Further, the wheel support 10 is formed with a front vertical wall portion (arm mounting reinforcement portion) 86 that protrudes inward in the vehicle width direction at a portion forward of the opening 84 (portion forward of the axle), and the upper arm 4, leading arm 5 and trailing arm 6 are connected to this front vertical wall portion 86. That is, the respective connecting portions 44, 54, 62 and bushes 48, 56, 64 on the wheel 2 side of the upper arm 4, leading arm 5 and trailing arm 6 described above are provided on this front vertical wall portion 86. As shown in FIG. 6, a reinforcing rib 86a is formed on the outer edge of this front vertical wall portion 86.

[0036] Further, the wheel support 10 is formed with a lower vertical wall portion (arm mounting reinforcement portion) 88 that protrudes inward in the vehicle width direction at a lower portion of the opening 84, and the lower arm 7 is connected to this lower vertical wall portion 88. That is, the above-mentioned connecting portion 70 and bush 72 on the wheel 2 side of the lower arm 7 are provided on this lower vertical wall portion 88.

[0037] Further, the wheel support 10 has a rear vertical wall portion (arm mounting reinforcement portion) 90 that protrudes inward in the vehicle width direction in a portion rearward of the opening 84 (portion rearward of the axle), and the toe control arm 8 is connected to this rear vertical wall portion 90. That is, the above-mentioned connecting portion 78 and bush 80 on the wheel 2 side of the toe control arm 8 are provided on this rear vertical wall portion 90.

[0038] Next, the connection structure of the upper arm 4, the leading arm 5, and the trailing arm 6 to the wheel support 19 will be described in more detail with reference to Figures 7 to 12. Figure 8 is a front view showing the peripheral structure of the wheel support of the rear suspension of Figure 4, Figure 9 is a rear view showing the peripheral structure of the wheel support of the rear suspension of Figure 4, Figure 10 is a top view for explaining the positional relationship of pivot parts in the wheel support of the upper arm and trailing arm of the rear suspension of Figure 4, Figure 11 is a side view for explaining the positional relationship of pivot parts in the wheel support of the upper arm and trailing arm of the rear suspension of Figure 4, Figure 12 is a front view for explaining the positional relationship of pivot parts in the wheel support of the upper arm and trailing arm of the rear suspension of Figure 4, and the wheel support is omitted in Figures 11 and 12.

[0039] 7 to 10, a bush housing 92 for holding the bush 48 of the upper arm 4 and a bush housing 94 for holding the bush 56 of the leading arm 5 are formed in an upper portion of the front vertical wall portion 86 of the wheel support 10. The bush housings 92, 94 are portions having a circular (annular) cross section and a predetermined thickness (15 mm in this embodiment) that surround the bushes 48, 56 (see FIG. 8), and are formed integrally with the front vertical wall portion 86 of the wheel support 10.

[0040] The bushes 48, 56 each have an axis extending in the front-rear direction of the vehicle, and these axis are journaled in bush housings 92, 94 so as to allow the wheel support 10 and the rear wheel 2 to move up and down along a predetermined trajectory. Here, the bush housings 92, 94 are formed so as to open on the rear side of the front vertical wall portion 86, and the bushes 48, 56 are fastened and journaled from the front sides of the bush housings 92, 94, respectively.

[0041] In this embodiment, each of the connecting portions 44, 54 of the upper arm 4 and the leading arm 5 is a pivot portion constituted by a bushing 48, 56 provided at each arm end and a bushing housing 92, 94 that holds the bushing 48.

[0042] Next, as shown in Figs. 10 and 11, each of the bushes 42, 56 is a pillow ball type bush having a predetermined length (indicated by symbols L1, L2) in the vehicle front-rear direction. In this embodiment, the bushes 42, 56 constituting the pivot portions (connecting portions) 46, 54 overlap in the vehicle fore-and-aft direction in top and side views, and this overlapping range is indicated by the reference symbol L3 in the drawings. In particular, as shown in Figures 4, 5 and 11, the bushes 42, 56 overlap in the vehicle fore-and-aft direction vertically above an intersection point P2 on imaginary extension lines of the trailing arm 6 and the lower arm 7 in side view.

[0043] 12, the area in which the bush 48 is formed at the pivot portion 46 of the upper arm 4 as viewed from the front of the vehicle is indicated by imaginary line A1, the area in which the bush 56 is formed at the pivot portion 54 of the leading arm 5 is indicated by imaginary line A2, the area in which the bush housing 92 is formed at the pivot portion 46 is indicated by imaginary line B1, and the area in which the bush housing 94 is formed at the pivot portion 54 is indicated by imaginary line B2. Note that the bush housings 92, 94 are not shown in FIG.

[0044] In this embodiment, as shown in Fig. 12, the pivot portion 46 of the upper arm 4 and the pivot portion 54 of the leading arm 5 are arranged to overlap in the vehicle up-down direction and the vehicle width direction in a front view. More specifically, as shown by reference character C in Fig. 12, the formation area A1 of the bush 42 and the formation area A2 of the bush 56 overlap in the vehicle up-down direction and the vehicle width direction. Also, as shown by reference character D in Fig. 12, the formation area B1 of the bush housing 92 and the formation area B2 of the bush housing 94 overlap in the vehicle up-down direction and the vehicle width direction.

[0045] In this embodiment, as shown in Figures 8 and 12, the pivot portion 46 of the upper arm 4 is disposed at an angle of approximately 45 degrees downward in the vertical direction of the vehicle and inward in the width direction of the vehicle with respect to the pivot portion 54 of the leading arm 5 when viewed from the front and rear.

[0046] Furthermore, in this embodiment, particularly as shown in Figures 9 and 12, a concave portion 5b is formed near the pivot portion 46 at the lower edge portion 5a of the leading arm 5, and when viewed from the front and rear, the pivot portion 46 of the upper arm 4 is positioned in the concave portion 5b of the lower edge portion 5a of the leading arm 5.

[0047] As a modified example, the bush housings 92, 94 of the pivot portions 46, 54 may be arranged to overlap in their forming areas, while the bushes 42, 56 of the pivot portions 46, 54 may not overlap in their forming areas.

[0048] The present invention is not limited to the configuration of the above-mentioned embodiment, but includes various other configurations. For example, in this embodiment, the left and right rear suspensions 1 are attached to the vehicle body by the subframe 3, but the present invention is not limited to this, and the rear suspensions 1 may be directly attached to the vehicle body. Furthermore, in order to improve the handling stability, for example, the leading arm 6 and the lower arm 7 may be connected to the wheel support 10 via a ball joint. Furthermore, the bushes are not limited to rubber bushes, and may be made of resin having the required elasticity.

[0049] Next, the effects of this embodiment will be described. The suspension device 1 for an automobile according to this embodiment includes a wheel support 10 that supports a wheel 2 and has an opening 84 formed in the center to allow an axle (not shown) to pass through, an upper arm 4 that extends from a connecting portion 44 on the vehicle body side toward the rear of the vehicle and is connected to the wheel support 10 above the axle, a leading arm 5 that extends from a connecting portion 52 on the vehicle body side toward the front of the vehicle and is connected to the wheel support above the axle, a trailing arm 6 that extends from a connecting portion 60 on the vehicle body side toward the rear of the vehicle and is connected to the wheel support 10 below the axle, a lower arm 7 that extends from a connecting portion 68 on the vehicle body side toward the front of the vehicle and is connected to the wheel support 10 below the axle, and a lower arm 8 that extends from a connecting portion 76 on the vehicle body side in the vehicle width direction and is connected to the wheel support 10 below the axle. The vehicle has a toe control arm 8 connected to a wheel support 10 on one side, and has a virtual kingpin axis IK vertically connecting an intersection P1 on each of the virtual extension lines of the upper arm 4 and the leading arm 5 and an intersection P2 on each of the virtual extension lines of the trailing arm 6 and the lower arm 7. The upper arm 4 and the leading arm 5 are connected to the wheel support 10 via pivot portions 46, 54, and are arranged so that the pivot portion 46 of the upper arm 4 and the pivot portion 54 of the leading arm 5 overlap in the fore-and-aft direction of the vehicle in a plan view and overlap in the vertical direction and the vehicle width direction of the vehicle in a front view, vertically above the intersection P2 on each of the virtual extension lines of the trailing arm 6 and the lower arm 7 in a side view. According to the present embodiment configured as described above, the imaginary kingpin axis IK can be made to extend in the vertical direction in a side view, and the imaginary kingpin axis IK can be brought close to the connection portions 46, 54 of the upper arm 4 and the leading arm 5 with the wheel support 10. As a result, the displacement of the imaginary kingpin axis IK can be suppressed.

[0050] Furthermore, according to this embodiment, the pivot portion 46 of the upper arm 4 is disposed at an angle of approximately 45 degrees downward in the vertical direction of the vehicle and inward in the width direction of the vehicle relative to the pivot portion 54 of the leading arm 5 in a front view. Therefore, the respective connection portions 46, 54 of the upper arm 4 and the leading arm 5 to the wheel support 10 can be brought close to each other in both the vertical and horizontal directions in a front view. This allows the imaginary kingpin axis IK to be effectively brought close to those connection portions 46, 54.

[0051] In addition, according to this embodiment, a front vertical wall portion 86 protruding inward in the vehicle width direction is formed in the portion of the wheel support 10 that is forward of the axle (opening 84 of the wheel support 10), and the pivot portion 46 of the upper arm 4 and the pivot portion 54 of the leading arm 5 are both provided on the front vertical wall portion 86 of the wheel support 10.Therefore, the pivot portions 46, 54 of the upper arm 4 and the trailing arm 5 can be integrally provided on the front vertical wall portion 86 of the wheel support 10, thereby ensuring the support rigidity of the upper arm 4 and the trailing arm 5.

[0052] In addition, according to this embodiment, a concave portion 5b is formed in the lower edge portion 5a near the pivot portion 54 of the leading arm 5, and in front and rear views, the pivot portion 46 of the upper arm 4 is positioned in the concave portion 5b of the lower edge portion 5a of the leading arm 5, so that the connection portion 46 with the wheel support 10 of the upper arm 4 and the connection portion 54 with the wheel support 10 of the leading arm 5 can be positioned in close proximity to each other.

[0053] In addition, according to this embodiment, the pivot portion 46 of the upper arm 4 and the pivot portion 54 of the leading arm 5 each include a bush 48, 56 provided at the end of each arm 4, 5 facing the wheel support 10, and a bush housing 92, 94 formed in the wheel support 10, and the bush 48 and the bush housing 92 at the pivot portion 46 of the upper arm 4 and the bush 56 and the bush housing 94 at the pivot portion 54 of the leading arm 5 are arranged so as to overlap in the vertical direction and the vehicle width direction in a front view, or the bush housings 92, 94 at those pivot portions 46, 54 are arranged so as to overlap in the vertical direction and the vehicle width direction in a front view, so that the connection portion 46 of the upper arm 4 with the wheel support 10 and the connection portion 54 of the leading arm 5 with the wheel support 10 can be more reliably arranged in close proximity to each other. [Explanation of symbols]

[0054] 1. Automobile suspension system / rear suspension 2 Rear wheels 3 Subframe 4 Upper arm (front upper link) 5 Leading arm (rear upper link) 6 Trailing arm (front lower link) 7 Lower arm (rear lower link) 8 Toe control arm (toe control link) 10 Wheel support (support member, hub carrier) 16 Shock absorbers (coil springs and dampers) 20 Front cross member 22 Rear cross member 24, 26 Side cross member 46 Upper arm 4 wheel side connection part (pivot part) 48 Upper arm 4 wheel side bush (pivot part) 54 Wheel side connection part (pivot part) of leading arm 5 56 Leading arm 5 wheel side bush (pivot part) 84 Wheel support opening 86 Front vertical wall of wheel support (arm connecting member) 92 Upper arm 4 bush housing (pivot part) 94 Leading arm 5 bush housing (pivot part) IK Virtual Kingpin Axis P1, P2 Intersection of the virtual extension lines of each arm A1 Formation range of the bush 42 of the upper arm in front view A2 Formation range of bush 56 of leading arm in front view B1 Formation range of the bush housing 92 of the upper arm in front view B2 Formation range of bush housing 94 of leading arm in front view C Overlapping area of ​​bush forming range A1 and A2 D Overlapping area of ​​bush housing forming range B1 and B2 L1, L2 Length of the bush in the vehicle's front-rear direction L3 Overlap length of bush in the longitudinal direction of the vehicle

Claims

1. A wheel support that supports a wheel and has an opening formed in the center through which an axle passes; an upper arm extending from a connecting portion on a vehicle body side toward a rear side of the vehicle and connected to the wheel support above the axle; a leading arm extending from a connecting portion on a vehicle body side toward a front side of the vehicle and connected to the wheel support above the axle; a trailing arm extending from a connecting portion on the vehicle body side toward the rear of the vehicle and connected to the wheel support below the axle; a lower arm extending from a connecting portion on a vehicle body side toward a front side of the vehicle and connected to the wheel support below the axle; a toe control arm extending in a vehicle width direction from a connecting portion on a vehicle body side and connected to the wheel support on a vehicle rear side of the lower arm, a virtual kingpin axis vertically connecting an intersection point on virtual extension lines of the upper arm and the leading arm and an intersection point on virtual extension lines of the trailing arm and the lower arm, the upper arm and the leading arm are connected to the wheel support via a pivot portion, vertically above an intersection of imaginary extension lines of the trailing arm and the lower arm in a side view, the pivot portion of the upper arm and the pivot portion of the leading arm are arranged to overlap in the vehicle front-rear direction in a plan view and to overlap in the vehicle up-down direction and the vehicle width direction in a front view, a recessed portion is formed in a lower edge portion near the pivot portion of the leading arm, and when viewed from the front, the pivot portion of the upper arm is disposed in the recessed portion of the lower edge portion of the leading arm.

2. 2. The automobile suspension device according to claim 1, wherein the pivot portion of the upper arm is disposed at an angle of approximately 45 degrees downward in the vehicle vertical direction and inward in the vehicle width direction with respect to the pivot portion of the leading arm when viewed from the front.

3. A vertical wall portion protruding inward in a vehicle width direction is formed on a portion of the wheel support that is forward of the axle, 3. The automobile suspension device according to claim 1, wherein the pivot portion of said upper arm and the pivot portion of said leading arm are both provided on a vertical wall portion of said wheel support.

4. the pivot portion of the upper arm and the pivot portion of the leading arm each include a bush provided at an end of the arm on a wheel support side and a bush housing formed in the wheel support, 4. An automobile suspension device as claimed in any one of claims 1 to 3, wherein the bush and bush housing at the pivot portion of the upper arm and the bush and bush housing at the pivot portion of the leading arm are arranged so as to overlap in the vertical direction and the vehicle width direction of the vehicle when viewed from the front, or each bush housing at the pivot portion of each arm is arranged so as to overlap in the vertical direction and the vehicle width direction of the vehicle when viewed from the front.

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