JP2010036841A - Rear suspension device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To secure the smooth action of an actuator for controlling a toe angle of a rear wheel without applying a large change to a constituent. <P>SOLUTION: The rear suspension device is provided with: an upper arm 6 arranged at a front side more than an axle 3 as a lateral arm; a front side lower arm 7 arranged at a front side more than the axle; and a rear side lower arm 8 arranged behind the axle and connected with a suspension spring S. In order to turn a hub carrier 4 to actively control a toe angle of the rear wheel, a toe control arm 9 which is expandable and contractible by the actuator 26 is connected to the hub carrier, and a connection link 21 is interposed between a rear side lower arm and the hub carrier so that the hub carrier can be turned in a required range of an angle making a virtual king pin shaft K for connecting respective connection parts of the upper arm and the lower side lower arm relative to the hub carrier as a center. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention provides a hub carrier that rotatably supports a rear wheel, a longitudinal arm that extends in the longitudinal direction of the vehicle body so as to mainly handle the longitudinal force, and a lateral direction of the vehicle body that mainly handles the lateral force. The present invention relates to a multi-link type rear suspension device connected to a vehicle body via a plurality of extending lateral arms.

  In recent years, a four-wheeled vehicle is provided with a mechanism for individually and actively controlling the toe angles (steering angles) of the left and right rear wheels for the purpose of improving the running stability of the vehicle. 1).

Various rear suspensions are used for four-wheeled vehicles, but a hub carrier that supports the rear wheel for rotation is provided with a trailing arm that mainly handles the longitudinal force and a mainly lateral force. A multi-link type connected to a vehicle body through a plurality of lateral arms is known (see Patent Document 2).
Japanese Patent Laid-Open No. 9-30438 JP 2005-225382 A

  However, in the multi-link type rear suspension apparatus as described above, when realizing a configuration in which the toe angle of the rear wheels is actively controlled, many components can be shared with a vehicle that does not perform toe angle control. This is convenient for reducing the manufacturing cost.

  FIG. 12 is a schematic diagram showing an example of a conventional multi-link type rear suspension device. The rear suspension device 101 includes a hub carrier 102, a trailing arm 103, and one upper arm 104 and two lower arms 105 and 106 as lateral arms. In such a configuration, an adjustment mechanism composed of an eccentric cam is provided at the joint 109 that connects the rear lower arm 106 and the vehicle body to finely adjust the toe angle at the time of shipment. However, it is conceivable to change the toe angle of the rear wheel W by using the same principle as described above, and the rear lower arm 106 can be expanded and contracted by an actuator. At this time, the hub carrier rotates with a line connecting the joints 107 and 108 connecting the upper arm 104 and the front lower arm 105 to the hub carrier 102 as virtual kingpin axes.

  However, the suspension spring S is normally connected to the rear lower arm 106, and the load of the vehicle body acts. For this reason, when an actuator is provided on the rear lower arm 106, an excessive bending stress is generated in the actuator, which causes a problem that smooth operation of the actuator becomes difficult.

  The present invention has been devised to solve such problems of the prior art, and its main purpose is to control the toe angle of the rear wheels without major changes to the components. An object of the present invention is to provide a rear suspension device configured to ensure a smooth operation of an actuator.

  In order to solve such a problem, in the present invention, as shown in claim 1, the hub carrier (4.62) for supporting the rear wheel (W) is extended in the longitudinal direction arm extending substantially in the longitudinal direction of the vehicle body. And a multi-link type rear suspension device connected to the vehicle body through a plurality of lateral arms extending in the lateral direction of the vehicle body, and an upper arm (6) disposed forward of the axle as the lateral arm. The front lower arm (7) disposed in front of the axle and the rear lower arm (8.63) disposed rearward of the axle and connected to the suspension spring (S) are configured to rotate the hub carrier. In order to actively control the toe angle of the rear wheel, a toe control arm (9, 65) that can be expanded and contracted by an actuator (26) is connected to the hub carrier. The rear lower arm and the rear lower arm so that the hub carrier can be rotated within a required angular range about a virtual kingpin axis (K) connecting the connecting portions of the upper arm and the front lower arm to the hub carrier. A link member (connect link 21 / steer crank 64) is interposed between the hub carrier and the hub carrier.

  According to this, since the toe control arm that can be expanded and contracted by the actuator is provided separately from the rear lower arm to which the vehicle body load is input from the suspension spring, it is possible to avoid the vehicle body load from acting on the actuator. Smooth operation can be ensured.

  In addition, compared with the conventional configuration in which one upper arm and two lower arms are provided as lateral arms (lateral arms) in which the toe angle control is not performed, the upper arm and one lower arm (front lower arm) for the hub carrier When the line connecting each connecting portion is a virtual kingpin axis, the other lower arm (rear lower arm) that restrains the rotation of the hub carrier around the virtual kingpin axis is not directly connected to the hub carrier, The hub carrier can be smoothly rotated in the angle range required for active toe angle control.

  And the component parts, that is, the front and rear direction arm, the upper arm and the front lower arm are generally left as they are, and the hub carrier may be provided with a new toe control arm mounting portion, and it is not necessary to make a major change to the vehicle body side member. Many components can be shared with vehicles that do not perform toe angle control.

  In this case, the toe control arm may be provided in such a manner that the outer end is connected to the hub carrier and the inner end is connected to the rear lower arm or the vehicle body. Further, the toe control arm is preferably arranged behind the lower arm. In addition, the toe control arm has a structure in which a direct-acting actuator generates a resistance force that maintains a constant length against an external force, so that it is one of the lateral arms that handle lateral force. It is possible to ensure high support rigidity against lateral force.

  In the rear suspension device, as shown in claim 2, the link member (connect link 21) moves the connecting portion (joint 23) to the hub carrier and the connecting portion (joint 24) to the rear lower arm vertically. It can be set as the structure provided so that it might connect in a direction.

  In this case, the toe control arm may be directly connected to the hub carrier, and the hub carrier is allowed to rotate by swinging the link member in accordance with the expansion / contraction operation of the toe control arm.

  In the rear suspension device, as shown in claim 3, the link member (steer crank 64) includes a connecting portion (joint 72) for the hub carrier and a connecting portion (joint 73) for the rear lower arm. A connecting portion (joint 74) for the toe control arm arranged on the side opposite to the connecting portion of the hub carrier across the connecting portion of the rear lower arm is provided so as to be laterally connected. According to the expansion / contraction operation, the link member can be swung around the connecting portion of the rear lower arm as a fulcrum to rotate the hub carrier.

  The front-rear arm is mainly responsible for the front-rear force and the braking force, that is, the external force that acts in the rotational direction of the rear wheel when the brake is operated, etc. Radius rod.

  As described above, according to the present invention, since the toe control arm that can be extended and contracted by the actuator is provided separately from the lower arm to which the vehicle body load is input from the suspension spring, it is possible to avoid the vehicle body load from acting on the actuator. The smooth operation of the actuator can be ensured. And since many components can be shared with the vehicle which does not perform toe angle control, a big effect is acquired in reducing manufacturing cost.

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

<First Embodiment>
FIG. 1 is a perspective view showing a first example of a rear suspension device according to the present invention. FIG. 2 is a schematic diagram of the rear suspension apparatus shown in FIG. 3 is a bottom view of the rear suspension apparatus shown in FIG. FIG. 4 is a perspective view showing the rear lower arm and the toe control arm shown in FIG. FIG. 5 is a perspective view showing a toe angle adjusting mechanism of the inner end of the toe control arm shown in FIG. Here, the positional relationship will be described in the front-rear, left-right, and up-down directions with respect to the vehicle body.

  The rear suspension device 1 is of a multi-link type with a trailing arm, and as shown in FIG. 2, a hub carrier 4 having an axle 3 that rotatably supports a rear wheel W, and a front of the hub carrier 4. A trailing arm (front / rear direction arm) 5 disposed on the front side, an upper arm (lateral direction arm) 6 disposed forward and above the axle 3, and a front lower arm (lateral arm disposed below and forward from the axle 3). ) 7, a rear lower arm (lateral arm) 8 disposed below and behind the axle 3, and a toe control arm 9 for actively controlling the toe angle of the rear wheel W by rotating the hub carrier 4. have.

  The trailing arm 5 extends substantially in the front-rear direction, and mainly handles the front-rear force and the braking force, that is, the external force acting in the rotation direction of the rear wheel W when the brake is operated. The upper arm 6, the front lower arm 7 and the rear lower arm 8 extend substantially in the left-right direction, and mainly handle lateral forces, that is, external forces acting in the left-right direction when the vehicle turns.

  In the rear suspension device 1, the joint 15 that connects the upper arm mounting portion 14 of the hub carrier 4 and the outer end of the upper arm 6, and the front lower arm mounting portion 17 of the hub carrier 4 and the outer end of the front lower arm 7 are connected. A line connecting the joint 18 becomes a virtual kingpin axis K, and the hub carrier 4 can rotate in a required angle range in the toe-in direction and the toe-out direction of the rear wheel W around the virtual kingpin axis K.

  The joint 15 at the outer end of the upper arm 6 is of a ball type, and the joint 18 at the outer end of the front lower arm 7 is of a rubber bush type having a central axis in the front-rear direction as shown in FIG. is there. In this rubber bush type joint 18, the ring rubber interposed between the inner cylinder part and the outer cylinder part of the rubber bush undergoes distorted deformation, that is, the centers of the inner cylinder part and the outer cylinder part arranged coaxially. The hub carrier 4 is allowed to rotate due to the deformation in the direction in which the line is inclined.

  As shown in FIG. 2, the trailing end of the trailing arm 5 is connected to the trailing arm mounting portion 12 of the hub carrier 4 via the joint 13, and the virtual kingpin axis is bent by the bending of the joint 13. The hub carrier 4 is allowed to rotate around the center.

  As shown in FIG. 1, the front end of the trailing arm 5 is connected to a vehicle-side member (not shown) via a rubber bush joint 11 having a substantially central axis in the left-right direction. As shown in FIG. 3, the inner ends of the front lower arm 7 and the rear lower arm 8 are connected to the subframe 35 via rubber bush type joints 16, 19, 25 having a central axis in the front-rear direction. Thus, the hub carrier 4 can move up and down within the range of the suspension stroke.

  In particular, here, a connection link (link member) 21 is provided between the rear lower arm 8 and the hub carrier 4 so that the rear lower arm 8 does not restrain the rotation of the hub carrier 4 about the virtual kingpin axis K. It is intervened.

  The connect link 21 is connected to the mounting portion 22 of the hub carrier 4 and the outer end of the rear lower arm 8 via joints 23 and 24 at both ends, and connects the two joints 23 and 24 in the vertical direction. It extends in the vertical direction.

  As shown in FIG. 4, the joint 23 that connects the hub carrier 4 and the connection link 21 is of a rubber bush type having a central axis in the front-rear direction. The joint 24 connecting the connect link 21 and the rear lower arm 8 is also of a rubber bush type having a central axis in the front-rear direction. In the rubber bush-type joints 23 and 24, the hub carrier 4 is allowed to rotate by causing deformation of the annular rubber interposed between the inner cylinder portion and the outer cylinder portion of the rubber bush.

  The rear lower arm 8 is provided with a spring receiving portion 41 to which the lower end of the suspension spring S is attached, and a damper attachment portion 42 to which the lower end of the damper D is connected, and the vehicle body from the suspension spring S to the rear lower arm 8 is provided. The load is input. The load of the vehicle body input to the rear lower arm 8 acts on the hub carrier 4 via the connect link 21, and tensile stress is generated in the longitudinal direction of the connect link 21 extending in the vertical direction.

  The toe control arm 9 includes a direct-acting actuator 26 that can extend and contract in the axial direction, and the hub carrier 4 rotates about the virtual kingpin axis K by extending and retracting the toe control arm 9 by the actuator 26. Thus, the toe angle of the rear wheel W can be changed.

  The toe control arm 9 is disposed behind the rear lower arm 8 so as to be substantially parallel to the rear lower arm 8. The outer end of the toe control arm 9 is connected to a steering arm 28 provided on the hub carrier 4 via a rubber bush type joint 29 having a central axis in the front-rear direction. As shown in FIG. 3, the inner end of the toe control arm 9 is extended from a position in the vicinity of the inner end of the rear lower arm 8 via a rubber bush type joint 31 having a central axis in the front-rear direction. It is connected to the mounting arm 30.

  The actuator 26 is a direct acting type in which the output rod 26a advances and retreats in the axial direction, and an electric motor (for example, a DC motor with a brush) that is a driving source and a planet that decelerates the rotation of the electric motor are provided inside the housing. A gear reducer and a feed screw mechanism that converts rotational motion into linear motion are housed. The output rod 26a is moved forward and backward by reversing the polarity by rotating the electric motor forward and backward using an H-bridge circuit or the like. Can be made.

  In this actuator 26, a resistance force that keeps the length constant against an external force is generated by an internal feed screw mechanism or the like, and the toe control arm 9 extends in the left-right direction and handles a lateral force. Function as.

  A joint 31 at the inner end of the toe control arm 9 is provided with a toe angle adjusting mechanism 51 for finely adjusting the toe angle at the time of shipment from the factory, as shown in FIG. In the toe angle adjusting mechanism 51, an eccentric cam 53 is provided on the head of the bolt 52 that is the central axis of the joint 31, and the eccentric cam 53 is regulated by a stopper 55 provided on the bracket 54 of the mounting arm 30. By rotating the eccentric cam 53, the center position of the joint 31, that is, the mounting position of the inner end of the toe control arm 9 is moved, whereby the hub carrier 4 is rotated and the toe angle of the rear wheel W is adjusted. be able to.

  In this rear suspension device 1, the trailing arm 103, the upper arm 104, and the front lower arm 105 are generally left as they are, and the rear lower arm 106 is connected via a connection link as compared with the configuration in which the toe angle control shown in FIG. The hub carrier 102 only needs to be provided with a toe control arm mounting portion, and there is no need to make major changes to the vehicle body side member such as the subframe. It can be shared with vehicles that do not perform toe angle control.

<Modification of the first embodiment>
FIG. 6 is a schematic diagram showing a modification of the rear suspension device shown in FIG. In the example of FIG. 2, the inner end of the toe control arm 9 is connected to the mounting arm 30 extending from the rear lower arm 8 via the joint 31. The end is directly connected to the vehicle body via a joint 57. Even with such a configuration, the same operation as in the above example is possible, but since it is necessary to provide the mounting portion of the toe control arm 9 on the vehicle body, from the viewpoint of sharing with a vehicle having a configuration that does not perform toe angle control The above example is excellent.

<Second Embodiment>
FIG. 7 is a perspective view showing a second example of the rear suspension device according to the present invention. FIG. 8 is a schematic diagram of the rear suspension apparatus shown in FIG. FIG. 9 is a perspective view of the rear suspension device shown in FIG. 7 as viewed obliquely from below. FIG. 10 is a bottom view of the rear suspension apparatus shown in FIG. 11 is a cross-sectional view showing an intermediate joint of the steer crank shown in FIG.

  As shown in FIG. 8, the rear suspension device 61 includes a hub carrier 62 including an axle 3 that rotatably supports a rear wheel W, a trailing arm 5 disposed in front of the hub carrier 62, and an axle 3 The upper arm 6 disposed further forward and above, the front lower arm 7 disposed below and forward from the axle 3, the rear lower arm 63 disposed below and rearward from the axle 3, and the hub carrier 62 are rotated. And a toe control arm 65 that actively controls the toe angle of the rear wheel W.

  The trailing arm 5, the upper arm 6, and the front lower arm 7 are the same as those in the example of FIG. 2 and are denoted by the same reference numerals, and detailed description thereof is omitted. However, as in the example of FIG. A line connecting the ball joint 15 connecting the carrier 62 and the upper arm 6 and the rubber bush joint 18 connecting the hub carrier 62 and the front lower arm 7 becomes a virtual kingpin axis K. The hub carrier 62 rotates around the center.

  In particular, here, unlike the example of FIG. 2, the rear lower arm 63 is not between the rear lower arm 63 and the hub carrier 62 so as not to restrain the rotation of the hub carrier 62 about the virtual kingpin axis K. Further, a steering crank (link member) 64 is interposed.

  The steer crank 64 is connected via a joint 74 disposed on the side opposite to the joint 72 for connecting to the mounting portion 71 of the hub carrier 62 with the intermediate joint 73 to which the outer end of the rear lower arm 63 is connected interposed therebetween. The outer ends of the toe control arms 65 arranged behind the rear lower arm 63 are connected to each other, and extend in a substantially horizontal direction so as to connect the joints 72 to 74 in the horizontal direction.

  The steer crank 64 swings around the rotation axis M of the intermediate joint 73 according to the expansion / contraction operation of the toe control arm 65 by the actuator 26, and the joint 72 connected to the hub carrier 62 is displaced accordingly. As a result, the hub carrier 62 rotates about the virtual kingpin axis K and the toe angle of the rear wheel W changes.

  As shown in FIG. 9, the intermediate joint 73 that connects the steer crank 64 and the rear lower arm 63 is of a ball bearing type having a substantially vertical central axis. The joint 74 that connects the steering crank 64 and the toe control arm 65 is of a rubber bush type having a central axis in the vertical direction. These joints 73 and 74 rotate around the central axis when the steering crank swings.

  On the other hand, the joint 72 connecting the steer crank 64 and the hub carrier 62 is of a rubber bush type having a central axis in the front-rear direction. In the rubber bush type joint 72, the hub carrier 4 is allowed to rotate by causing a distorted deformation in the annular rubber interposed between the inner cylinder portion and the outer cylinder portion of the rubber bush.

  The rear lower arm 63 is provided with a spring receiving portion 81 to which the lower end of the suspension spring S is attached and a damper attachment portion 82 to which the lower end of the damper D is connected, as in the above example. The vehicle body load is input to the rear lower arm 63. The vehicle body load input to the rear lower arm 63 acts on the hub carrier 62 via the steering crank 64, and bending stress is generated in the steering crank 64 extending in the lateral direction.

  The inner end of the rear lower arm 63 is connected to the subframe 35 via a rubber bush type joint 75 having a central axis in the front-rear direction. As shown in FIG. The line connecting the end joint 75 and the joint 72 connecting the front end of the steer crank 64 to the hub carrier 62 becomes the center line C of the rear lower arm 63. The central axis of the intermediate joint 73 serving as the center of swinging 64 is offset. For this reason, when a lateral force is input from the hub carrier 62 to the joint 72 of the steering crank 64, a rotational moment is generated in the steering crank 64. This rotational moment force is received by the actuator 26 of the toe control arm 65.

  The intermediate joint 73 of the steering crank 64 includes a ball bearing 91 as shown in FIG. An outer ring 91 a of the ball bearing 91 is fixed to an outer holder portion 92 formed on the steer crank 64. The inner ring 91 b of the ball bearing 91 is fixed to a distance collar 96 fixed to a U-shaped mounting portion 93 formed at the inner end of the rear lower arm 63 with a mounting bolt 94 and a mounting nut 95. The ball bearing 91 is of an angular type suitable when a moment load is applied. The preload nut 97 that is screwed into the distance collar 96 presses the inner ring 91b via the preload disc spring 98, so that the preload is applied. Has been granted.

  In addition to the ball bearing, a rubber bush can be used for the intermediate joint 73. In this case, it is preferable to use a rubber material that exhibits a high spring constant with respect to a load that causes galling deformation.

  In this example, the inner end of the toe control arm 65 is connected to the mounting arm 76 extended from the rear lower arm 63 via the joint 77, but, similarly to the example shown in FIG. You may make it connect with a vehicle body directly via a joint.

1 is a perspective view showing a first example of a rear suspension device according to the present invention. FIG. It is a schematic diagram of the rear suspension apparatus shown in FIG. FIG. 2 is a bottom view of the rear suspension device shown in FIG. 1. FIG. 2 is a perspective view showing a rear lower arm and a toe control arm shown in FIG. 1. It is a perspective view which shows the toe angle adjustment mechanism of the inner end of the toe control arm shown in FIG. It is a schematic diagram which shows the modification of the rear suspension apparatus shown in FIG. It is a perspective view which shows the 2nd example of the rear suspension apparatus by this invention. It is a schematic diagram of the rear suspension apparatus shown in FIG. It is the perspective view which looked at the rear suspension apparatus shown in FIG. 7 from diagonally downward. FIG. 8 is a bottom view of the rear suspension device shown in FIG. 7. It is sectional drawing which shows the intermediate joint of the steer crank shown in FIG. It is a perspective view which shows an example of the rear suspension apparatus which does not perform toe angle control.

Explanation of symbols

1 Rear Suspension Device 3 Axle 4 Hub Carrier 5 Trailing Arm 6 Upper Arm 7 Front Lower Arm 8 Rear Lower Arm 9 Toe Control Arm 21 Connect Link (Link Member)
26 Actuator 28 Steering arm 35 Subframe 51 Toe angle adjusting mechanism 61 Rear suspension device 62 Hub carrier 63 Rear lower arm 64 Steer crank (link member)
65 Toe control arm K Virtual kingpin shaft W Rear wheel S Suspension spring

Claims (3)

A multi-link type rear suspension device in which a hub carrier that supports a rear wheel is connected to a vehicle body via a longitudinal arm extending in the longitudinal direction of the vehicle body and a plurality of lateral arms extending in the lateral direction of the vehicle body. Because
The lateral arm includes an upper arm disposed in front of the axle, a front lower arm disposed in front of the axle, and a rear lower arm disposed rearward of the axle and connected to a suspension spring.
In order to rotate the hub carrier to actively control the toe angle of the rear wheel, a toe control arm that can be expanded and contracted by an actuator is connected to the hub carrier,
Between the rear lower arm and the hub carrier so that the hub carrier can be rotated within a required angular range around a virtual kingpin axis connecting the connecting portions of the upper arm and the front lower arm to the hub carrier. A rear suspension device characterized in that a link member is interposed in the rear suspension device.   2. The rear suspension device according to claim 1, wherein the link member is provided so as to vertically connect a connecting portion to the hub carrier and a connecting portion to the rear lower arm. The toe control arm is arranged such that the link member is connected to the hub carrier, the connection portion to the rear lower arm, and the side opposite to the connection portion of the hub carrier across the connection portion of the rear lower arm. Is provided so as to connect the connecting portion to the lateral direction,
The hub carrier is rotated according to claim 1, wherein the link member swings around the connecting portion of the rear lower arm as a fulcrum according to the expansion / contraction operation of the toe control arm. The rear suspension device described.

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