JP4534153B2 - Rear suspension device for automobile - Google Patents

Description

  The present invention relates to a rear suspension device for an automobile, and more particularly to a rear suspension device for a multi-link automobile.

  The multi-link suspension is known as a suspension type that can obtain high movement performance because each link can be optimally arranged for five degrees of freedom of movement excluding the vertical stroke of the wheel. Yes. It is also known that each link is attached to a suspension cross member so that the mutual positional relationship between the links and the positional relationship with respect to the road surface does not change.

  As a suspension device having such a form, the present applicant has proposed a multi-link type rear wheel suspension device capable of obtaining sufficient vibration isolation performance while ensuring high steering stability (Patent Document 1). ). This suspension has five links with elastic bushes at the end on the vehicle body side, and applies an urging force (preload) to the elastic bushes of each link using the vertical reaction force of the shock absorber. It is. Therefore, this suspension has excellent characteristics such as high rigidity and responsiveness, and further, the vibration blocking effect by the elastic bushing can be obtained. This suspension device includes a pair of side cross members extending in the front-rear direction on both the left and right sides of the vehicle body as suspension cross members, and a front cross member and a rear cross member extending in the vehicle width direction so as to connect them together. Each link is connected to these cross members.

JP 2003-335117 A

In automobiles equipped with such a highly maneuverable suspension device, there is a strong demand to further improve the exercise performance because it originally has high exercise performance. The present inventors have found the following problems in the process of advancing research and development to meet such demands.
First, in an automobile (mainly a front engine rear drive type automobile) in which a propeller shaft, a rear differential, and the like are arranged below the suspension cross member of the rear suspension, the arrangement of the suspension cross member is the same as the arrangement of the rear differential and the like. Because of this, it will be restricted. When the propeller shaft or the like passes below the front cross member extending in the vehicle width direction, the front cross member is formed in a shape curved toward the vehicle body upper side. On the other hand, since the toe control link of the multi-link suspension is disposed on the front side of the wheel, the toe control link is connected to the front cross member or another cross member in the vicinity thereof.

  During braking, a load (tensile force) is applied to the toe control link from the wheel toward the outside in the vehicle width direction. During turning, a load (compression force) is applied from the outer wheel to the inside in the vehicle width direction. Is mainly received by the front cross member. The front cross member does not extend straight in the direction of receiving such a load, and is easily deformed as it is curved upward. The present inventors have found that such a deformation of the front cross member has a considerable influence on the suspension performance. That is, a toe change occurs as the length of the front cross member in the vehicle width direction is changed by the above-described tensile force or compressive force. For example, during braking, the braking stability is lowered by changing in the toe-out direction. On the other hand, when the turning outer wheel side turns to the toe-in direction during turning, the stability of the vehicle tends to increase unless the amount is excessive.

  In particular, in the suspension device disclosed in Patent Document 1 described above, the vertical reaction force of the shock absorber is also applied to each link, and thus such problems can occur remarkably. In the suspension device of Patent Document 1 described above, the toe control link is connected to the front cross member, and the front cross member is disposed below the rear differential and the power plant frame (the rear differential and the front portion of the vehicle). In order to pass the power unit (the engine and the transmission) integrally connected) or the like, it is greatly curved upward.

  On the other hand, in order to increase the rigidity of the front cross member in the vehicle width direction, it is effective to provide a member that extends straight in the vehicle width direction below the portion curved upward, but as described above, A rear differential or the like passes below. Therefore, if a reinforcing member that extends straight in the vehicle width direction is provided, the minimum ground clearance is lowered, which is not practical.

  Therefore, the present invention has been made to solve the above-described problems of the prior art, and is capable of suppressing toe changes during braking and turning without sacrificing the minimum ground clearance. An object of the present invention is to provide a rear suspension device for an automobile of the type. It is another object of the present invention to provide a multi-link type automobile rear suspension device capable of obtaining an appropriate toe-in characteristic of a turning outer wheel during turning.

In order to achieve the above object, the present invention is a rear suspension device for a multi-link type automobile, comprising a pair of side cross members extending in the longitudinal direction of the vehicle body on the left and right sides in the vehicle width direction, and the pair of side crosses. A front cross member having an upper curved portion extending in the vehicle width direction so as to connect the members to each other and curving upward so that the propeller shaft or the rear differential is passed therethrough, and a pair of sides behind the front cross member The suspension cross member includes a suspension cross member formed by a rear cross member extending in the vehicle width direction so as to connect the side cross members to each other, and a toe control link that is swingably connected to both ends of the front cross member in the vehicle width direction. Suspension link supported by member and front cross member A pair of left and right first reinforcing members that connect the rear cross member and a pair of left and right second reinforcing members that connect the front cross member and the vehicle body, and the first reinforcing member has a front cross section in plan view. From the connecting portion with the member toward the connecting portion with the rear cross member, it extends obliquely rearward and inward in the vehicle width direction, and its axis is inclined at a first angle with respect to the direction in which the front cross member extends. The second reinforcing member extends obliquely forward of the vehicle body and outward in the vehicle width direction from the connecting portion with the front cross member toward the connecting portion with the vehicle body in a plan view, and the axis thereof is forward. are arranged so as to be inclined at a second angle with respect to the extending direction of the cross member, the first angle and the second angle varies from each other, the first angle is characterized by greater than the second angle.
In the present invention configured as described above, since the two reinforcing members, the first reinforcing member and the second reinforcing member extending obliquely, are connected to the front cross member, the load applied to the front cross member from the toe control link is reduced. It can be dispersed effectively. Here, the load component distributed to the second reinforcing member is received by the vehicle body, and the load component distributed to the first reinforcing member is also received by the side cross member via the rear cross member and the rear cross member. In the rear suspension device of the present invention having different load distribution paths as described above, there are two reinforcing members, and the first angle of the first reinforcing member with respect to the front cross member and the second reinforcing member Since the second angle with respect to the front cross member is different from each other, the load component received by the first reinforcing member and the second reinforcing member can be appropriately distributed. Therefore, deformation of the front cross member can be effectively suppressed. As a result, toe changes during braking and turning can be suppressed. Further, since both the first reinforcing member and the second reinforcing member are provided so as to connect the front cross member and the vehicle body or the rear cross member, the first reinforcing member and the second reinforcing member do not interfere with the rear differential below the upper curved portion. I can do it. Therefore, the minimum ground clearance is not sacrificed.

In the present invention, the first angle is larger than the second angle.
In the present invention configured as described above, at the time of braking, the second reinforcing member extending at a second angle smaller than the first angle supports the front cross member so as to stretch, and the braking force is applied to the toe control link. Receive the applied tensile force. Furthermore, since a part of such tensile force is disperse | distributed to a back cross member by the 1st reinforcement member, a deformation | transformation of a front cross member is suppressed more reliably. As a result, toe-out due to deformation of the front cross member when a braking force is applied can be reliably suppressed. On the other hand, during turning, a relatively large compressive force is applied to the toe control link from the turning outer wheel side, but a part of such compressive force is received by the vehicle body via the second reinforcing member, and the remaining force is The front cross member and the rear cross member are distributed via the first reinforcing member. Here, when the input load from the turning outer wheel is very large, for example, when the turning speed is high, it is often desired to improve the vehicle stability by directing the turning outer wheel in the toe-in direction. In addition, each member in which the force is dispersed deforms not a little depending on the dispersed force. On the other hand, in the present invention, since the first reinforcing member extends at a first angle larger than the second angle, the first reinforcing member is closer to the front cross member in a direction perpendicular to the second reinforcing member. It can be extended with. Therefore, it is possible to reliably distribute the remaining force excluding the amount distributed to the second reinforcing member out of the large compressive force applied from the turning outer ring side during turning to the front cross member as well as the first reinforcing member. I can do it. When a large compressive force is applied, the front cross member is easily deformed by the force dispersed in the front cross member, and the toe-in of the turning outer ring can be obtained by such deformation. In this case, since the first reinforcing member extends in an oblique direction, a part of the compressive force is reliably transmitted to the first reinforcing member, and as a result, the toe-in amount can be prevented from becoming excessively large.
As a result, when a large input load is applied during turning, an appropriate toe-in characteristic of the turning outer wheel can be obtained by utilizing the deformation of the front cross member.
In the present invention, preferably, the connecting portion between the first reinforcing member and the front cross member and the connecting portion between the second reinforcing member and the front cross member are provided so as to overlap each other.
In order to achieve the above object, the present invention is a rear suspension device for a multi-link type automobile, comprising a pair of side cross members extending in the longitudinal direction of the vehicle body on the left and right sides in the vehicle width direction, and the pair of side crosses. A front cross member having an upper curved portion extending in the vehicle width direction so as to connect the members to each other and curving upward so that the propeller shaft or the rear differential is passed therethrough, and a pair of sides behind the front cross member The suspension cross member includes a suspension cross member formed by a rear cross member extending in the vehicle width direction so as to connect the side cross members to each other, and a toe control link that is swingably connected to both ends of the front cross member in the vehicle width direction. Suspension link supported by member and front cross member A pair of left and right first reinforcing members that connect the rear cross member and a pair of left and right second reinforcing members that connect the front cross member and the vehicle body, and the first reinforcing member has a front cross section in plan view. From the connecting portion with the member toward the connecting portion with the rear cross member, it extends obliquely rearward and inward in the vehicle width direction, and its axis is inclined at a first angle with respect to the direction in which the front cross member extends. The second reinforcing member extends obliquely forward of the vehicle body and outward in the vehicle width direction from the connecting portion with the front cross member toward the connecting portion with the vehicle body in a plan view, and the axis thereof is forward. The first reinforcing member is disposed so as to be inclined at a second angle with respect to the extending direction of the cross member, the first angle and the second angle are different from each other, and the connecting portion of the first reinforcing member with the front cross member and the second reinforcing member With a front cross member Connecting portion is provided one above, are fastened together by bolts is characterized by being configured by connected to the front cross member.
In the present invention configured as described above, since the two reinforcing members, the first reinforcing member and the second reinforcing member extending obliquely, are connected to the front cross member, the load applied to the front cross member from the toe control link is reduced. It can be dispersed effectively. Here, the load component distributed to the second reinforcing member is received by the vehicle body, and the load component distributed to the first reinforcing member is also received by the side cross member via the rear cross member and the rear cross member. In the rear suspension device of the present invention having different load distribution paths as described above, there are two reinforcing members, and the first angle of the first reinforcing member with respect to the front cross member and the second reinforcing member Since the second angle with respect to the front cross member is different from each other, the load component received by the first reinforcing member and the second reinforcing member can be appropriately distributed. Therefore, deformation of the front cross member can be effectively suppressed. As a result, toe changes during braking and turning can be suppressed. Further, since both the first reinforcing member and the second reinforcing member are provided so as to connect the front cross member and the vehicle body or the rear cross member, the first reinforcing member and the second reinforcing member do not interfere with the rear differential below the upper curved portion. I can do it. Therefore, the minimum ground clearance is not sacrificed.
The connecting portion of the first reinforcing member with the front cross member and the connecting portion of the second reinforcing member with the front cross member are provided so as to overlap each other and are fastened together with bolts and connected to the front cross member. Therefore, the first auxiliary member and the second auxiliary member are arranged on two sides of a virtual triangle having the connecting portion fastened together by the bolt as a vertex. Thus, by arranging the first auxiliary member and the second auxiliary member so as to form two sides of a virtual triangle, the load can be supported more reliably.

In the present invention, preferably, the connecting portion of the first reinforcing member with the front cross member and / or the connecting portion of the second reinforcing member with the front cross member is provided on the axis of the toe control link.
In this invention comprised in this way, the load added to a front cross member from a toe control link can be received more reliably. In addition, the toe control link and the first auxiliary member or the second reinforcing member are arranged on two sides of a virtual triangle whose apex is a connecting portion with the front cross member. Thus, by arranging the toe control link and the first auxiliary member or the second auxiliary member so as to constitute two sides of a virtual triangle, the load can be supported more reliably.

In the present invention, preferably, the connecting portion of the first reinforcing member with the front cross member and the connecting portion of the second reinforcing member with the front cross member are both provided at the same location.
In the present invention configured as described above, the first auxiliary member and the second auxiliary member are arranged on two sides of a virtual triangle having the connecting portion provided at the same place as the apex. Thus, by arranging the first auxiliary member and the second auxiliary member so as to form two sides of a virtual triangle, the load can be supported more reliably.

  In the present invention, preferably, the connecting portion of the first reinforcing member with the front cross member and the connecting portion of the second reinforcing member with the front cross member are configured to be fastened together by bolts and connected to the front cross member. Yes.

In the present invention, preferably, a power plant frame extends alongside the propeller shaft or the rear differential below the upper curved portion of the front cross member.
In the automobile having such a configuration, it is necessary to largely curve the upper curved portion of the front cross member by extending the power plant frame to the side of the propeller shaft or the rear differential. However, even with such a large curve, the toe change during braking and turning can be reliably suppressed by the action of the first reinforcing member and the second reinforcing member according to the present invention described above. Further, even when the power plant frame is provided and there is no excess in the space below the front cross member, the minimum ground clearance is not sacrificed.

In the present invention, preferably, the suspension link is provided with an elastic bushing at least at an end portion on the vehicle body side, and a support member for a rear wheel of the automobile is connected to the vehicle body. The lower end of a shock absorber provided with a coil spring and a damper is pivotally attached, and a preload is applied to the elastic bush using the vertical reaction force of the shock absorber.
In the present invention, the suspension having such a configuration, that is, the elastic bush at the end of the vehicle body is bent in advance, and the load applied to each suspension link during turning or braking is not delayed by the bending of the elastic bush. Even if the suspension is configured to be transmitted directly to the suspension cross member or the load of the shock absorber is further applied to the suspension cross member, the operation of the first and second reinforcing members according to the present invention described above Thus, toe change during braking and turning can be reliably suppressed.

  According to the present invention, it is possible to suppress a toe change during braking and turning without sacrificing the minimum ground clearance. Furthermore, it is possible to obtain an appropriate toe-in characteristic of the turning outer wheel during turning.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
First, the overall configuration of the rear suspension apparatus according to the first embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a perspective view of the rear suspension device according to the present embodiment as viewed from an oblique right side in front of the vehicle body, and FIG. 2 is a plan view of the rear suspension device according to the present embodiment as viewed from above the vehicle body. The rear suspension device for an automobile according to the present embodiment is mainly composed of a rear suspension A and a suspension cross member (subframe) B, and the suspension cross member B is attached to a vehicle body C (only part of which is shown in FIG. 4). Yes.

First, a schematic configuration of an automobile to which the present embodiment is applied will be described.
Although the vehicle of the present embodiment is not shown, the engine is mounted in the engine room at the front of the vehicle body, while the rear differential 1 (shown only in FIG. 2) is disposed at the rear of the vehicle body and the rear wheel 2 (vehicle body in FIG. 1). This is a rear-wheel drive vehicle in which only the right one is shown. A transmission (not shown) is assembled on the rear side of the engine body, and the rotational output from the transmission is transmitted to the rear differential 1 via a propeller shaft 4 (shown only in FIG. 2). . The rotational output from the rear differential 1 is transmitted to the rear wheel 2 via the drive shaft 5.
In this automobile, a power unit composed of an engine and a transmission and the rear differential 1 are integrally connected by a power plant frame 3 (shown only in FIG. 2). This power plant frame is for configuring the power train including the power unit and the rear differential 1 as a rigid structure as a whole. The power plant frame 3 suppresses windup vibration of the rear differential 1. Thus, the response of the driving force of the rear wheel 2 to the accelerator operation can be improved. The power plant frame 3 has a U-shaped cross-sectional shape, and is disposed in a floor tunnel (not shown) so that the propeller shaft passes through the inner side of the U-shape, and the rear differential 1 In addition, it passes below a front cross member 17 described later.

Next, a schematic configuration of the rear suspension A will be described.
In the rear suspension A, the wheel support (support member) 11 of the rear wheel 2 is connected to the vehicle body by five independent I links 6 to 10 so as to be able to stroke, and each link is made use of the vertical reaction force of the shock absorber 14. This is a preload type multi-link suspension in which an urging force (preload) is applied to 6 to 10 elastic bushes 26. Each I link includes two upper links 6 and 7 on the front and rear sides of the vehicle that virtually constitute the upper arm, two lower links 8 and 9 on the front and rear sides of the vehicle that virtually constitute the lower arm, and The toe control link 10 regulates the rotational displacement of the rear wheel 2 around the virtual kingpin axis K determined by the placement of the virtual upper arm and the lower arm. Then, the upper links 6 and 7 and the lower links 8 and 9 swing up and down around the end on the vehicle body side so that the wheel support 11 and the rear wheel 2 stroke up and down along a predetermined locus. It has become.
Further, a shock absorber 14 including a coil spring 12 and a damper 13 is disposed so as to allow an appropriate biasing force and damping force at the same time while allowing such a stroke of the rear wheel 2. In this shock absorber 14, the coil spring 12 and the damper 13 are arranged substantially coaxially and generally have a cylindrical shape that is long in the vertical direction, and a cylindrical bracket 15 disposed on the upper end side thereof is attached to a vehicle body (not shown). The lower end portion of the damper 13 (the lower end portion of the shock absorber 14) is pivotally attached to the vehicle body inner side of the wheel support 11. Accordingly, the reaction force of the coil spring 12 and the damper 13 (upper and lower reaction force of the shock absorber) corresponding to the shared load at the rear of the vehicle body and the stroke of the rear wheel 2 directly acts on the wheel support 11.

Next, a schematic configuration of the suspension cross member B will be described.
The suspension cross member B is roughly composed of four steel plate members combined in a generally rectangular frame shape in plan view, and each includes a front cross member 17 and a rear cross member 18 extending in the vehicle width direction, and left and right sides thereof. A pair of side cross members 19 and 20 extending in the front-rear direction are provided on both the left and right sides of the vehicle body so as to connect the end portions.
As shown in FIG. 2, the front cross member 17 extends substantially straight in the vehicle width direction when viewed from above the vehicle body, and both end portions in the vehicle width direction are respectively on the front end sides of the left and right side cross members 19 and 20. It is joined. Further, as shown in FIG. 1, the front cross member 17 is formed with an upper curved portion 17c that is largely curved so that the center portion in the longitudinal direction is located above the left and right ends when viewed in the longitudinal direction of the vehicle body. Has been. In the present embodiment, the upward curved portion 17 c is formed over almost the entire area inside the side cross members 19 and 20. With such an upward curved portion, the rear differential 1 and the power plant frame 3 can be disposed below the front cross member 17.

On the other hand, as shown in FIG. 2, the rear cross member 18 extends substantially straight in the vehicle width direction when viewed from above the vehicle body, and both ends in the vehicle width direction are rearward of the left and right side cross members 19, 20, respectively. It is joined to the end side. Further, when viewed in the longitudinal direction of the vehicle body, it is formed in an inverted trapezoidal shape in which the length of the upper edge is larger than that of the lower edge (see FIG. 5).
As shown in FIG. 2, mounting portions 18b are disposed on the upper edge of the rear cross member 18 at positions corresponding to mounting portions 18a (see FIG. 3) of the rear lower link 9 described later (see FIG. 3). As shown in FIG. 5, the rear differential 1 is suspended by brackets 22 attached to these attachment portions 18b via elastic mounts 21.
Further, as shown in FIG. 2, the left and right side cross members 19 and 20 are gently curved so that the center portions in the longitudinal direction are located inward of the vehicle body as compared with the both end sides. Further, as can be seen from the perspective view shown in FIG. 1, the left and right side cross members 19 and 20 extend substantially horizontally from the rear end portion to the substantially central portion when viewed from the side of the vehicle body, while the front side portions thereof. Extends obliquely downward toward the front of the vehicle body, and is disposed such that the front part of the center is lower than the rear part.

Further, the side cross members 19, 20 have mounts 40, 42, 44 for rigidly connecting the entire suspension cross member B to the vehicle body, and each of the side cross members 19, 20 has a front end portion, a substantially central portion, and a rear portion. Arranged at three points at the end. The substantially central mount 42 is disposed on the upper surface of the mount mounting portion extending inward of the vehicle body from the substantially central portion of the side cross members 19 and 20, and is mounted on the central mount 42 as viewed from above the vehicle body. A straight line connecting the rear end mount 23 is positioned so as to be substantially parallel to a longitudinal center line L (shown only in FIG. 2) of the vehicle body. On the other hand, the mount 40 at the front end is located outside the vehicle body as compared with the mounts 42 and 44 at the center and rear ends. In the present embodiment, the suspension cross member B is rigidly connected to the vehicle body in this way, so that the support rigidity of the suspension A with respect to the vehicle body is increased and the vehicle body rigidity is also increased.
The suspension cross member B is provided with a first reinforcing member 50 and a second reinforcing member 52 described later.

Next, referring to FIGS. 3 to 7, the mounting structure and arrangement of the suspension links 6 to 10 to the suspension cross member B will be described. FIG. 3 is a top view of the right side portion of the rear suspension device according to the present embodiment as viewed from the upper side of the vehicle body, and FIG. 4 is a right side portion of the rear suspension device according to the present embodiment as viewed from the inner side of the vehicle body. FIG. 5 is a partially broken side view, FIG. 5 is a rear view of the right side portion of the vehicle body of the rear suspension device according to the present embodiment as viewed from the rear side of the vehicle body, and FIG. 6 is the right side portion of the vehicle body of the rear suspension device of the present embodiment. FIG. 7 is a bottom view of the suspension cross member, the toe control link, and the reinforcing member of FIG. 7 viewed from the lower side of the vehicle body. FIG. 7 shows the suspension cross member and the reinforcing member of the right side portion of the rear suspension device of the present embodiment from the front side of the vehicle body. FIG.
Since the rear suspension device of this embodiment is configured symmetrically in the vehicle width direction, only the right side portion of the vehicle body will be mainly described below, and the description of the left side portion of the vehicle body will be omitted.

First, as shown in FIGS. 3 and 5 to 7, the left and right ends of the front cross member 17 are each provided with a mounting portion 17 a that protrudes downward in the vicinity of the joint with the side cross members 19 and 20. An end of the toe control link 10 on the vehicle body side is connected to each mounting portion 17a via a rubber bush 26. As shown in FIG. 3, the toe control link 10 extends from the mounting portion 17a toward the outside of the vehicle body substantially laterally (in the vehicle width direction) when viewed from above the vehicle body. 27 is connected to the wheel support 11.
Next, as shown in FIGS. 3 to 7, the rear cross member 18 is formed with mounting portions 18a extending downward from the left and right ends of the lower edge portion thereof. A vehicle body side end of the rear lower link 9 is attached via a rubber bush 26. As shown in FIG. 3, the rear lower link 9 extends from the mounting portion 18 a toward the outside of the vehicle body while being inclined slightly forward as seen from above the vehicle body, and the wheel-side end is supported by the ball joint 27. 11. The rear lower link 9 is longer than the front lower link 8.

Next, as shown in FIGS. 3, 4, and 6, the front side portions of the side cross members 19, 20 are protruded downward in the vicinity of the front side of the joint portion with the front cross member 17. 1 mounting portions 19a and 20a (see FIGS. 1 and 2) are arranged, and the first lower mounting portions 19a and 20a are respectively provided with a front lower link (lower trailing link) 8 via a rubber bush 26. The end of the car body is attached. As shown in FIG. 3, the front lower link 8 is tilted to a greater extent than the front upper link 6 from the first mounting portion 19 a (20 a (see FIGS. 1 and 2)) when viewed from above the vehicle body. The end of the wheel side is connected to the wheel support 11 by a ball joint 27. The front lower link 8 is longer than the upper links 6 and 7.
Further, as shown in FIGS. 3, 6 and 7, the front portions of the side cross members 19 and 20 are protruded upward in the vicinity of the rear side of the joint portion with the front cross member 17. 2 mounting portions 19b and 20b (see FIG. 1 and FIG. 2) are disposed, and these second mounting portions 19b and 20b are respectively end portions of the front upper link (upper trailing link) 6 on the vehicle body side. Is attached. As shown in FIG. 3, the front upper link 6 extends rearwardly so as to be gradually located rearward from the second mounting portions 19 b and 20 b toward the outer side of the vehicle body as viewed from above the vehicle body. The wheel side end is connected to the wheel support 11 by a ball joint 27.

Next, as shown in FIGS. 3, 5, and 6, third attachment portions 19 c and 20 c are disposed on the rear portions of the side cross members 19 and 20. End portions of the rear upper link 7 on the vehicle body side are attached to 19c and 20c via a rubber bush 26. As shown in FIG. 3, the rear upper link 7 extends from the third mounting portion 19c, 20c so as to be located forward as it moves from the third mounting portion 19c, 20c toward the outside of the vehicle body. The end on the side is connected to the wheel support 11 by a ball joint 27. The rear upper link 7 has substantially the same length as the front upper link 6.
Next, as shown in FIG. 5, when viewed from the rear of the vehicle body, the upper links 6 and 7 are slightly upwardly inclined from the side cross member 19 toward the wheel support 11 outside the vehicle body. On the contrary, the front lower link 8 is inclined slightly downward toward the outside of the vehicle body, and the rear lower link 9 and the toe control link 10 both extend substantially horizontally.

Next, the action of the suspension A by the arrangement of the links 6 to 10 will be described with reference to FIGS.
First, as shown in FIG. 3, the two lower links 8 and 9 are arranged so as to approach each other toward the outer side of the vehicle body as viewed from above the vehicle body. A toe-in is applied geometrically as the vehicle is displaced rearward (front-rear force compliance steer). That is, for example, when the braking force from the road surface acts on the rear wheel 2 toward the rear of the vehicle body during braking of the automobile, the two lower links 8 and 9 are slightly moved around the end portion on the vehicle body side due to the bending of the rubber bush 26, respectively. Thus, the wheel side end is displaced rearward of the vehicle body. At this time, if the front lower link 8 tilts backward toward the outside of the vehicle body and the rear lower link 9 tilts forward toward the vehicle body outward, the front lower link 8 is moved along with the rotational displacement of each of the links. The wheel side end of the rear wheel 2 is displaced inward of the vehicle body, and the wheel side end of the rear lower link 9 is displaced outward of the vehicle body, so that the alignment of the rear wheel 2 changes in the toe-in direction.

Next, the virtual kingpin axis K is the instantaneous center of rotation of the rear wheel 2 in the steering direction (toe direction). When viewed from above the vehicle body as shown in FIG. In addition, it becomes a virtual axis passing through the intersection of the axis centers of the two upper links 6 and 7 and the intersection of the axis centers of the two lower links 8 and 9. In this embodiment, the virtual kingpin axis K of the rear wheel 2 is slightly rearwardly inclined so as to be positioned rearward of the vehicle body as viewed from the side of the vehicle body as seen from the side of the vehicle body and viewed in the longitudinal direction of the vehicle body. The upper end is slightly inclined so as to be located outward of the vehicle body (see FIG. 5).
Further, the intersection k1 (see FIG. 4) with the road surface of the virtual kingpin axis K as viewed from the side of the vehicle body is further away from the ground contact point G of the rear wheel 2, and the caster trail of the rear wheel 2 has a negative value. It has become. As a result, the lateral force acting on the ground contact point G with the road surface of the rear wheel 2 when the vehicle is turning crosses the front of the vehicle body of the virtual kingpin axis K, and this lateral force directly causes the toe-in to the rear wheel 2. Directional moment force acts.
Thereby, the rubber bushes 26 of the two lower links 6 and 7 are mainly bent, and the toe-in amount of the wheel 2 is increased (lateral force compliance steer).
That is, in the case of the rear suspension A of this embodiment, the toe-in amount of the left and right rear wheels 2 is increased by the longitudinal force compliance steer when braking the vehicle, and the toe-in amount of the rear wheel 2 outside the turn is increased when the vehicle is turning. Increased by lateral force compliance steer. Although a detailed description is omitted, in the rear suspension A, the toe-in amount of the rear wheel 2 is increased by the roll steer at the time of bumping due to the arrangement configuration of the links 6 to 10.

Next, the configuration and arrangement of the shock absorber 14 will be described with reference to FIGS.
As shown in FIG. 3, the shock absorber 14 is disposed so as to vertically pass through the middle between the front links 6, 8 and the rear links 7, 9 when viewed from above the vehicle body, When viewed from the side of the vehicle body, it extends substantially vertically (see FIG. 4), and when viewed from the rear of the vehicle body, the upper end side is inclined so as to be located inside the vehicle body (see FIG. 5). In the upper end portion of the shock absorber 14, as shown by a broken line only in FIG. 4, the upper end portion of the rod 13a of the damper 13 is fixed to the upper end portion of the cylindrical bracket 15 via a rubber bush or the like. A cylindrical resin bump stopper 28 is disposed concentrically with the rod 13a so as to extend downward therefrom. The bump stopper 28 abuts against the upper end portion of the outer cylinder of the damper 13 when the coil spring 12 contracts by a predetermined amount or more when the suspension A is bumped. Since it becomes higher by one step, the proximity displacement of the rear wheel 2 toward the vehicle body is restricted.
Further, an odd-shaped flange portion 29 that is particularly long in the longitudinal direction of the vehicle body is provided at the lower end portion of the bracket 15 of the shock absorber 14, and its upper surface is joined and fastened to the lower frame of the vehicle body. On the other hand, an upper sheet for holding the upper end portion of the coil spring 12 is formed on the lower surface of the flange portion 29, and the lower end portion of the coil spring 12 disposed so as to surround the outer cylinder of the damper 13 is the lower end of the outer cylinder of the damper 13. It is held by a lower sheet portion 13b provided on the side. Further, an annular mounting portion 13 c is projected from the lower end portion of the damper 13, and is pivotally attached to the end portion of the connecting portion 30 that extends inward from the wheel support 11 of the rear wheel 2.

  Specifically, the connecting portion 30 of the wheel support 11 is integrally formed inside the main body of the wheel support 11 through which the axle of the rear wheel 2 passes, and as shown in FIG. The upper arm 31 and the lower arm 32 extending from the upper and lower ends of the support 11 body toward the inside of the vehicle body and integrated at the front end, and the upper arm 31 and the lower arm 32 are connected to the intermediate portions in the vehicle width direction. And an intermediate arm portion 33 extending in the up-down direction so as to be connected to each other. Then, from the intermediate arm portion 33 that is the A-shaped horizontal bar to the tip portions of the upper arm portion 31 and the lower arm portion 32 that are the upper ends of the A shape (tip portions inside the vehicle body of the connecting portion 30). The support shaft 34 is disposed, and the end of the support shaft 34 protrudes inward of the vehicle body from the end of the connecting portion 30, and is inserted into the lower end mounting portion 13 c of the damper 13. It is fixed through. Thus, by making the connecting part 30 substantially A-shaped, the weight of the connecting part 30 and thus the wheel support 11 as a whole can be reduced while securing sufficient rigidity against the load in the vertical direction. The increase in unsprung weight due to the provision of the can be suppressed, and deterioration of the exercise performance can be prevented.

With the above-described configuration, the shared load at the rear of the vehicle body and the vertical reaction force of the shock absorber 14 directly act on the rear wheel 2 via the connecting portion 30 of the wheel support 11. In this way, by actively utilizing the reaction force acting from the shock absorber 14 and biasing the wheel support 11 in a predetermined direction in advance, the alignment of the rear wheel 2 is optimized and the rubber of each link 6-10. An urging force in an optimal direction is applied to each bush 26. That is, each rubber bush 26 is pre-compressed in an optimum direction by the vertical reaction force of the shock absorber 14 so that a sharp driving feeling applicable to a sports car can be obtained even in a multi-link suspension.
Specifically, due to the vertical reaction force of the shock absorber 14, (1) a moment force in the direction of the negative camber is applied to the rear wheel 2 so as to overcome the lateral force during turning, and (2) during turning A moment force in the direction of toe-in is applied before the lateral force of the vehicle acts, and (3) an urging force to the front of the vehicle body is applied to the rubber bushes 26 of the lower links 8 and 9 that have a particularly large influence on the ride comfort. Like to do.

Next, these three functions and effects will be described with reference to FIGS.
FIG. 8 is an explanatory diagram of the moment force in the negative camber direction due to the vertical reaction force of the shock absorber, FIG. 9 is an explanatory diagram of the moment force in the toe-in direction due to the vertical reaction force of the shock absorber, and FIG. It is explanatory drawing of the moment force around the axle shaft by the vertical reaction force of a shock absorber.
First, as schematically shown in FIG. 8, when the rear suspension A on the right side of the vehicle body is viewed from the rear, the shock absorber 14 has a reaction force Fc in the axial center X direction via the wheel support 11. 2 so as to generate a moment force Mn in the direction of the negative camber sufficiently large, in other words, in the vehicle body inward so that the arm length of the moment force Mn due to the vertical reaction force of the shock absorber 14 is sufficiently large. They are relatively spaced apart. Specifically, for example, the length d (the length of the arm of the negative camber moment force Mn due to the reaction force of the shock absorber 14) of the perpendicular line dropped from the center C of the rear wheel 2 to the axis X of the shock absorber 14. It is preferable that the ratio be equal to or greater than a predetermined ratio set in advance with respect to the radius D of the rear wheel 2 (the arm length of the moment force Mp of the positive camber due to the lateral force).

Here, the setting of the predetermined ratio will be described. First, the magnitude of the moment force Mn in the direction of the negative camber acting on the rear wheel 2 by the vertical reaction force Fc of the shock absorber 14 is determined by the axis X of the shock absorber 14. To the rear wheel center C (the length of the arm of the moment) and the shock absorber reaction force Fc. However, in general, in the rear suspension A of an automobile, a shared load and a buffer on the rear wheel 2 outside the turn are obtained so as to obtain a target turning performance of the automobile, for example, a maximum lateral acceleration targeted during turning. The hardness of the coil spring 12 of the device 14, the maximum grip force of the rear wheel 2, and the like are set, so that the shock absorber reaction force Fc itself is generally determined.
Therefore, in order to increase the moment force Mn in the direction of the negative camber sufficiently, it is necessary to substantially increase the length of the arm of the moment. For example, assuming a limit region where the maximum lateral acceleration is generated in the rear wheel when the vehicle is turning, the shock absorber reaction is greater than the moment force Mp of the positive camber acting on the rear wheel 2 by the limit lateral force Fs at that time. The length of the moment arm described above may be set so that the moment force Mn of the negative camber due to the force Fc increases. In other words, the arm length d and moment Mp of the moment force Mn are set so that the moment force Mn of the negative camber acting on the rear wheel 2 in the limit region of the lateral force Fs is larger than the moment force Mp of the positive camber. The ratio with the arm length D may be set by experiment or the like.

More specifically, generally, a moment force Mp in the direction of the positive camber acts directly on the rear wheel 2 outside the turn by the lateral force Fs when the vehicle is turning, and the moment force Mp increases with the lateral force Fs. On the other hand, when the moment force Mn in the negative camber direction is applied to the rear wheel 2 by the vertical reaction force Fc of the shock absorber 14 as described above, the lateral acceleration increases when the vehicle turns, and the roll of the vehicle body increases. The reaction force Fc increases as the coil spring 12 of the shock absorber 14 is compressed, and the moment force Mn of the negative camber due to the reaction force Fc also increases.
Accordingly, the shock absorber 14 is disposed as in this embodiment, and the initial value of the moment force Mn of the negative camber due to the vertical reaction force Fc of the shock absorber 14 (when the vehicle is stopped or traveling straight at a constant speed). If the positive camber moment force Mp due to the lateral force Fs increases during turning, the negative camber moment force Mn that overcomes this will be reduced to the lateral force limit region of the rear wheel 2. It can be generated. Thus, the rear wheel 2 is urged toward the negative camber in the direction of camber change in the rear wheel 2 outside the turn, that is, in the lateral direction of the vehicle body in the rubber bush 26 of each link 6-10. Such a biasing force in a certain direction is applied (pre-compression), whereby a microscopic wobbling of the rear wheel 2 can be eliminated and a sharp driving feeling can be obtained.

  Secondly, in the rear suspension A of this embodiment, as shown in FIG. 4, the axis X of the shock absorber 14 is set with respect to the virtual kingpin axis K of the rear wheel 2 slightly tilted rearward when viewed from the side of the vehicle body. The shock absorber axis X is positioned so as to extend substantially in the vertical direction, and is positioned so as to be non-parallel to the virtual kingpin axis K and not to intersect with the virtual kingpin axis K (see FIG. 5) inward of the virtual kingpin axis K. . Thus, when the rear wheel 2 on the right side of the vehicle body is viewed from above the vehicle body as schematically shown in FIG. 9, the vertical reaction force Fc of the shock absorber 14 is counterclockwise moment force around the virtual kingpin axis K, that is, A moment force Mt in the toe-in direction is generated. In other words, the vertical reaction force of the shock absorber 14 is used to urge the rear wheel 2 in the toe-in direction before the lateral acceleration or posture change occurs in the vehicle (initial state). When the toe-in is applied due to the lateral force acting on the rear wheel 2, the delay due to the bending of the rubber bushing 26 of each link 6 to 10 does not occur, and this also increases the rigidity and responsiveness. A high and sharp driving feeling can be obtained.

Third, in the rear suspension A of this embodiment, as schematically shown in FIG. 10, the shock absorber 14 has a shaft center X at the rear side of the rear wheel 2 relative to the center C of the rear wheel 2 at the inner side of the rear wheel 2. And is arranged so as to extend in a substantially vertical direction. Thus, as shown in the drawing, the vertical reaction force Fc of the shock absorber 14 acts on the wheel support 11 from the substantially vertical upper side behind the center C of the rear wheel 2 (right side in the figure) as seen from the left side of the vehicle body. A clockwise moment force Mw is generated. As a result, the upper links 6 and 7 are urged toward the rear of the vehicle body, and the urging force toward the rear of the vehicle body acts on the rubber bushing 26 of the links 6 and 7, and the lower links 8 and 9 are respectively applied to the front of the vehicle body. As a result, an urging force toward the front of the vehicle body acts on the rubber bush 26 of each of the links 8 and 9.
Thus, the rubber bushes 26 of the upper links 6 and 7 are all made extremely hard, while the rubber bushes 26 of the lower links 8 and 9 are made relatively soft. That is, the rubber bush 26 is made relatively soft for each of the lower links 8 and 9 that have a relatively great influence on the ride comfort, and the rubber bush 26 is pre-compressed ahead of the vehicle body by the vertical reaction force of the shock absorber 14. It is doing. In this state, the rubber bush 26 has almost no allowance for the forward bending of the vehicle body, so that when the force (for example, driving force) forward of the vehicle body acts on the rear wheel 2, the rubber bush 26 hardly bends. The transmission of force to the vehicle body is performed.
On the other hand, when a force (for example, a shock from an irregular road surface) is input to the rear wheel 2 with the rubber bush 26 pre-compressed in front of the vehicle body as described above, the input acts on the rubber bush 26 by this input. When the force to be applied becomes larger than the above-described urging force and the direction of the resultant force is reversed, the rubber bush 26 bends backward as opposed to the initial state, and the rear wheel 2 is displaced rearward of the vehicle body. That is, the backward input is delayed or absorbed from the rear wheel 2 to the vehicle body.

Next, the first reinforcing member 50 and the second reinforcing member 52 of the suspension cross member B will be described with reference to FIGS.
First, the arrangement of the reinforcing members 50 and 52 will be described.
As shown in FIG. 2, the first reinforcing member 50 is provided on each of the left and right sides in the vehicle width direction, one end 50 a is connected to the front cross member 17, and the other end 50 b is connected to the rear cross member 18. ing. The second reinforcing member 52 is provided on each of the left and right sides in the vehicle width direction, one end 52a is connected to the front cross member 17, and the other end 52b is connected to the vehicle body C (see FIG. 7).
Each of the pair of left and right first reinforcing members 50 is obliquely toward the rear side of the vehicle body and the inner side in the vehicle width direction from one end 50a connected to the front cross member 17 toward the other end 50b in plan view. It extends. Further, the pair of left and right second reinforcing members 52 are both in front of the vehicle body and outward in the vehicle width direction from one end 52a connected to the front cross member 17 toward the other end 52b in plan view. It extends diagonally.

Here, as described above, the toe control link 10 extends in the vehicle width direction in plan view, and coincides with the direction in which the front cross member 17 extends. In FIG. 3, both the direction of extension of the axis and the front cross member 17 of the toe control link 10 is shown by a chain line L _A.
As shown in FIG. 3, the first reinforcing member 50 extends at an angle α (narrow angle between the axis lines L ₅₀ and L _A ) with respect to the direction in which the front cross member 17 extends (vehicle width direction). The reinforcing member 52 is disposed so as to extend at an angle β (narrow angle between the axes L ₅₂ and L _A ) different from the angle α with respect to the direction in which the front cross member 17 extends. In the present embodiment, the angle α is larger than the angle β. The second reinforcing member 52 is formed shorter than the first reinforcing member 50.

With these configurations, the first reinforcing member 50 extends rearward in the vehicle body and inward in the vehicle width direction, and the other end 50b is disposed at a position close to the side cross member 19 (20). The second reinforcing member 52 extends forward of the vehicle body and outward in the vehicle width direction at a small angle with respect to the direction L _A in which the front cross member 17 extends, and the other end 52b is rigid on the side cross member 19 (20). The tie mount 40 is disposed at a position substantially in the vehicle longitudinal direction.
Further, with the arrangement as described above, the first reinforcing member 50 and the second reinforcing member 52 do not interfere with the rear differential 1, the power plant frame 3, and the like arranged below the upper curved portion 17 c of the front cross member 17. I am doing so.

Next, the attachment structure of the 1st reinforcement member 50 and the 2nd reinforcement member 52 is demonstrated.
As shown in FIGS. 3, 6, and 7, a bracket 17 b is fixed to the lower surface of the front cross member 17 at a position near the joint between the front cross member 17 and the side cross member 19 (20). The one end portions 50a and 52a of the first reinforcing member 50 and the second reinforcing member 52 are connected to the lower end portion of the bracket 17b. The mounting portion 17a of the toe control link 10 described above is provided on the lower surface portion of the front cross member 17 adjacent to the outer edge in the vehicle width direction of the bracket 17b.
As shown in FIGS. 6 and 7, one end 50a of the first reinforcing member 50 and one end 52a of the second reinforcing member 52 are connected to one end 50a by bolts (and nuts) 54 extending in the vehicle body vertical direction. It is being fixed to the lower end part of the bracket 17b in order of the one end part 52a. That is, the reinforcing members 50 and 52 are coupled to the front cross member 17 by being fastened together by bolts (and nuts) 54 at the same location. Here, as shown in FIG. 3, the connecting portions (54, 50 a, 52 a) are provided on the axis L _A of the toe control link 10.

  As shown in FIGS. 6 and 7, the other end portion 50 b of the first reinforcing member 50 is a lower end portion of a bracket 18 c provided on the rear cross member 18 by a bolt (and nut) 56 extending in the vehicle body vertical direction. It is fixed to. The other end portion 52b of the second reinforcing member 52 is fixed to the lower surface portion of the vehicle body C by bolts (and nuts) 58 extending in the vehicle body vertical direction. In the present embodiment, the other end 52b is fixed to a rear side frame (not shown) extending in the longitudinal direction of the vehicle body C.

Next, the effect of the 1st reinforcement member 50 and the 2nd reinforcement member 2 is demonstrated.
In the present embodiment, since the front cross member 17 is supported by the two reinforcing members 50 and 52, deformation of the front cross member 17 can be effectively suppressed. Further, since each of the reinforcing members 50 and 52 extends obliquely with respect to the front cross member 17, a load applied to the front cross member 17 that also extends in the vehicle width direction from the toe control link 10 that extends in the vehicle width direction is effective. As a result, deformation of the front cross member 17 can be suppressed.

  Here, the load component received by the second reinforcing member 52 is directly received by the vehicle body C. On the other hand, the load component received by the first reinforcing member 50 is received by the rear cross member 18 and is also received by the side cross members 19 and 20 via the rear cross member 18, and finally the rigid mounts 40, 42, 44. Is received by the vehicle body C. In such a case, in the present embodiment, the first reinforcing member 50 extends obliquely from the one end 50a toward the other end 50b toward the rear side of the vehicle body and the inner side in the vehicle width direction. The load received by 50 can be effectively distributed to the rear cross member 18, the side cross members 19, 20 and the like. In such a case, since the first reinforcing member 50 and the second reinforcing member 52 extend in different directions, that is, the angles α and β (see FIG. 3) with respect to the front cross member 17 are different from each other. The load component received by the member 50 and the second reinforcing member 52 can be appropriately distributed. Therefore, the deformation of the front cross member 17 can be more reliably suppressed. Further, by appropriately allocating the load component, it is possible to prevent the front cross member 17 from being bent and deformed in the longitudinal direction of the vehicle body due to the provision of the reinforcing members 50 and 52 on the front cross member 17. .

  Next, during braking, a load (tensile force) directed outward in the vehicle width direction is applied to the front cross member 17 from the toe control links 10 on both the left and right sides in the vehicle width direction. In the present embodiment, since the second reinforcing member 52 extends obliquely outward from the front cross member 17 in the vehicle width direction, the front cross member 17 is supported so as to stretch and receives such a tensile force. Further, since the second reinforcing member 52 is connected to the vehicle body C, the front cross member 17 can be supported more reliably. In particular, since the angle β at which the second reinforcing member 52 extends is smaller than the angle α, the tensile force applied from the toe control link 10 can be received more reliably. Furthermore, since part of the tensile force is distributed to the rear cross member 18 by the first reinforcing member 50, the deformation of the front cross member 17 is more reliably suppressed. As a result, toe-out due to deformation of the front cross member 17 when a braking force is applied can be reliably suppressed.

  On the other hand, during turning, a large force is applied to the front cross member 17 from the toe control link 10 on the turning outer wheel side inward in the vehicle width direction, and a force smaller than the turning outer wheel is applied from the turning inner ring. Due to these forces, a relatively large load (compression force) is applied to the front cross member 17 from the turning outer ring side. In such a case, as described above, such a compressive force is received by the vehicle body C via the second reinforcing member 52 and also distributed to the rear cross member 18 and the like via the first reinforcing member 50. As a result, the compressive force is received by the entire suspension cross member including the reinforcing members 50 and 52. Therefore, deformation of the front cross member is effectively suppressed. In particular, since the angle α at which the first reinforcing member 50 extends is different from the angle β, the direction of the force applied to the first reinforcing member 50 and the direction of the force applied to the second reinforcing member 52 are different from each other. The load applied from the toe control link 10 can be appropriately dispersed. As a result, a change in toe-in due to deformation of the front cross member 17 during turning can be suppressed.

  Here, when the input load from the turning outer wheel is very large, for example, when the turning speed is high, it is often desired to improve the vehicle stability by directing the turning outer wheel in the toe-in direction. As described above, the load applied to the front cross member 17 is distributed to the reinforcing members 50 and 52, the rear cross member 18, and the like, but these members are deformed to some extent according to the distributed force. The input load is very large, and depending on the arrangement of the reinforcing members 50 and 52, such a slight deformation affects the toe change. In the present embodiment, such a deformation is used, and when the input load from the turning outer wheel is large, the turning outer wheel is directed in the toe-in direction. This point will be described. First, in the present embodiment, the angle α at which the first reinforcing member 50 extends is made larger than the angle β at which the second reinforcing member 52 extends. 17 can extend at an angle closer to a direction orthogonal to the second reinforcing member 52 than the second reinforcing member 52. In this way, of the large compressive force applied from the turning outer wheel side during turning, the remaining force received by the second reinforcing member 52 is distributed not only to the first reinforcing member 50 but also to the front cross member 17. It can be made. Therefore, when the input load from the turning outer ring side is large, the front cross member 17 can be deformed by the force distributed to the front cross member 17, and the toe-in of the turning outer ring can be obtained. On the other hand, a part of the load is reliably transmitted to the first reinforcing member 50 extending in the oblique direction, so that the toe-in amount can be prevented from becoming excessively large. As a result, when a large input load is applied during turning, an appropriate toe-in characteristic of the turning outer wheel can be obtained by utilizing the deformation of the front cross member 17.

Next, the connecting portions (50a, 52a, 54) of the reinforcing members 50, 52 to the front cross member 17 are provided on the axis L _{A of} the toe control link 10, so The load applied to the member 17 can be received more reliably, and as a result, the deformation of the front cross member 17 is more reliably suppressed.
Further, since the reinforcing members 50 and 52 are fastened to the front cross member 17 at the same location (50a, 52a and 54), the load applied to the front cross member 17 from the toe control link 10 can be received more reliably. I can do it. In other words, as described above, the first reinforcing member 50 and the second reinforcing member 52 extend at different angles α and β with respect to the front cross member 17, thereby virtually linking the connecting portions (50 a, 52 a, 54). This constitutes two sides of the triangle. In the present embodiment, the toe control link 10 (axis line L _A ) extends so as to bisect the vertices of the virtual triangle, and the reinforcing members 50 and 52 are connected to the toe control link 10 (axis line L _A). ) Form two virtual triangles. By arranging each member (10, 50, 52) so as to constitute two sides of such a virtual triangle, the load can be reliably supported. Therefore, the load applied to the front cross member 17 can be reduced, and deformation of the front cross member 17 can be suppressed.

Next, the connecting portions (50a, 52a, 54) of the reinforcing members 50, 52 to the front cross member 17 are provided on the bracket 17b. The bracket 17b is provided adjacent to the mounting portion 17a of the toe control link 10. Therefore, the load applied from the toe control link 10 can be directly received, and the deformation of the front cross member 17 can be more reliably suppressed.
Next, since the first reinforcing member 50 connects the front cross member 17 and the rear cross member 18, the deformation of the front cross member 17 can be suppressed and the rigidity of the suspension cross member B as a whole can be increased. I can do it. Further, since the angle α at which the first reinforcing member 50 extends is larger than the angle β at which the first reinforcing member 52 extends, the first reinforcing member 52 interferes with the rear differential 1 inside the vehicle body and its bracket 22. You can avoid it. Furthermore, the other end 50b of the first reinforcing member 50 can be disposed at a position closer to the side cross members 19 and 20 and the rigid mounts 42 and 44. In this case, the first reinforcing member 50 is added to the first reinforcing member 50. The load component is effectively received by the side cross members 19 and 20 and the rigid mounts 42 and 44.
In the present embodiment, the first reinforcing member 50 and the second reinforcing member 52 are attached to the front cross member 17 together with one bolt 54, but as a modification, in two places, that is, The reinforcing members 50 and 52 may be fastened together with two bolts, or only one of the reinforcing members 50 and 52 may be attached with two bolts.

Next, as shown in FIG. 11, in the second embodiment of the present invention, one end 60 a of the first reinforcing member 60 is positioned adjacent to the connection portion of the front cross member 17 with the side cross member 19 (20). The attachment portion 17a of the toe control link 10 is attached to the lower surface portion of the one end portion 60a. The other end 60 b of the first reinforcing member 60 is attached to the rear cross member 18. On the other hand, the second reinforcing member 62 has one end 62a attached to the front cross member 17 at the inner side in the vehicle width direction and slightly forward from the position of the one end 60a of the first reinforcing member 60 described above. The part 62 is attached to the vehicle body. Other configurations are the same as those of the first embodiment described above.
In the second embodiment, the mounting position of the first reinforcing member 62 to the front cross member 17 and the position of the mounting portion 17a of the toe control link 10 coincide with each other. The load applied to the front cross member 17 from the link 10 can be received directly and reliably. In the second embodiment, the same configuration as that of the first embodiment described above has the same function and effect as those described in the first embodiment.

It is the perspective view which looked at the rear suspension apparatus by 1st Embodiment of this invention from the diagonal right side ahead of a vehicle body. It is the top view which looked at the rear suspension apparatus by 1st Embodiment from the vehicle body upper direction. It is the top view which looked at the vehicle body right side part of the rear suspension apparatus by 1st Embodiment from the vehicle body upper side. It is the partially broken side view which looked at the vehicle body right side part of the rear suspension apparatus by 1st Embodiment from the vehicle body inner side. It is the rear view which looked at the vehicle body right side part of the rear suspension apparatus by 1st Embodiment from the vehicle body rear side. It is the bottom view which looked at the suspension cross member, toe control link, and reinforcement member of the vehicle body right side part of the rear suspension device of a 1st embodiment from the vehicle body lower side. It is the front view which looked at the suspension cross member and the reinforcement member of the vehicle body right side part of the rear suspension apparatus of 1st Embodiment from the vehicle body front side. It is explanatory drawing of the moment force of the direction of a negative camber by the vertical reaction force of a buffering device. It is explanatory drawing of the moment force of the direction of toe-in by the vertical reaction force of a buffering device. It is explanatory drawing of the moment force around the axle shaft by the vertical reaction force of the shock absorber. FIG. 6 is a bottom view of a suspension cross member, a toe control link and a reinforcing member of a right side portion of a vehicle body of a rear suspension device according to a second embodiment of the present invention as viewed from the vehicle body lower side.

Explanation of symbols

A Rear suspension B Suspension cross member C Car body 2 Rear wheel 6 Front upper link 7 Rear upper link 8 Front lower link 9 Rear lower link 10 Toe control link 11 Wheel support (support member)
14 shock absorber 17 front cross member 17a toe control link mounting portion 18 rear cross member 19, 20 side cross member 30 wheel support connecting portion 40, 42, 44 mount 50, 60 first reinforcing member 52, 62 second reinforcing member 50a , 52a, 60a, 62a One end portions 50b, 52b, 60b, 62b of the first and second reinforcing members The other end portions 52, 54, 56 of the first and second reinforcing members Bolts (and nuts)
K virtual kingpin axis X axis L ₅₀ and L _{52 of} shock absorber axis L _A direction of extending front cross member 17 of reinforcing link member and axis α of toe control link angle β of first reinforcing member relative to front cross member β 2 Angle of the reinforcing member to the front cross member

Claims (6)

A multi-link automobile rear suspension device,
A pair of side cross members extending in the longitudinal direction of the vehicle body on the left and right sides in the vehicle width direction, extending in the vehicle width direction so as to connect the pair of side cross members to each other, and passing a propeller shaft or a rear differential below the pair. A suspension cross member comprising a front cross member having an upward curved portion curved upward, and a rear cross member extending in the vehicle width direction so as to connect the pair of side cross members to each other behind the front cross member. When,
A suspension link supported by the suspension cross member, including a toe control link swingably connected to both ends of the front cross member in the vehicle width direction;
A pair of left and right first reinforcing members that connect the front cross member and the rear cross member;
A pair of left and right second reinforcing members that connect the front cross member and the vehicle body,
The first reinforcing member extends obliquely rearward and inward in the vehicle width direction from the connecting portion with the front cross member toward the connecting portion with the rear cross member in a plan view, and the axis thereof Arranged to be inclined at a first angle with respect to the direction in which the front cross member extends,
The second reinforcing member extends obliquely forward of the vehicle body and outward in the vehicle width direction from the connecting portion with the front cross member toward the connecting portion with the vehicle body in a plan view, and the axis thereof is the front portion Arranged so as to be inclined at a second angle with respect to the extending direction of the cross member,
The first angle and the second angle varies from each other, said first angle rear suspension of a motor vehicle, characterized in that greater than said second angle. The connecting portion between the front cross member of the connecting portion and the second reinforcing member between the front cross member of the first reinforcing member, an automobile rear suspension apparatus according to claim 1, wherein it is provided one above. A multi-link automobile rear suspension device,
A pair of side cross members extending in the longitudinal direction of the vehicle body on the left and right sides in the vehicle width direction, extending in the vehicle width direction so as to connect the pair of side cross members to each other, and passing a propeller shaft or a rear differential below the pair. A suspension cross member comprising a front cross member having an upward curved portion curved upward, and a rear cross member extending in the vehicle width direction so as to connect the pair of side cross members to each other behind the front cross member. When,
A suspension link supported by the suspension cross member, including a toe control link swingably connected to both ends of the front cross member in the vehicle width direction;
A pair of left and right first reinforcing members that connect the front cross member and the rear cross member;
A pair of left and right second reinforcing members that connect the front cross member and the vehicle body,
The first reinforcing member extends obliquely rearward and inward in the vehicle width direction from the connecting portion with the front cross member toward the connecting portion with the rear cross member in a plan view, and the axis thereof Arranged to be inclined at a first angle with respect to the direction in which the front cross member extends,
The second reinforcing member extends obliquely forward of the vehicle body and outward in the vehicle width direction from the connecting portion with the front cross member toward the connecting portion with the vehicle body in a plan view, and the axis thereof is the front portion Arranged so as to be inclined at a second angle with respect to the extending direction of the cross member,
The first angle and the second angle varies from each other,
The connecting portion of the first reinforcing member to the front cross member and the connecting portion of the second reinforcing member to the front cross member are provided so as to overlap each other and are fastened together by bolts to be connected to the front cross member. rear suspension of a motor vehicle, characterized in that it is constituted by. Connecting portions between the front cross member of the connecting portion and / or the second reinforcing member between the front cross member of said first reinforcing member according to claim 1 to 3 is provided on the axis of the toe control links The rear suspension device for an automobile according to any one of the preceding claims. The rear suspension device for an automobile according to any one of claims 1 to 4 , wherein a power plant frame extends to the side of the propeller shaft or the rear differential below the upper curved portion of the front cross member. The suspension link is provided with an elastic bush at least at an end on the vehicle body side, and connects a support member for the rear wheel of the automobile to the vehicle body. A coil spring is provided on the vehicle inner side of the rear wheel support member. The automobile according to any one of claims 1 to 5 , wherein a lower end portion of a shock absorber including a damper is pivotally attached, and a preload is applied to the elastic bush using a vertical reaction force of the shock absorber. Rear suspension device.

Images