JP6074319B2 - Vehicle suspension system - Google Patents

Description

  The present invention relates to a vehicle suspension device applied to a rear wheel of a vehicle.

  Some vehicle suspension systems have a wheel alignment adjustment structure. For example, in the adjustment structure described in Patent Document 1 below, the first support portion of the lower arm is configured to be movable in the front-rear direction and the vehicle width direction, and the second support portion of the lower arm is configured to be movable in the front-rear direction. Has been. Thereby, it can assemble | attach to a vehicle body, adjusting the position of a lower arm.

JP 2004-203143 A

  However, in the vehicle suspension device, the first support portion and the second support portion of the lower arm are assembled to the vehicle body via a rubber bush (elastic body). For this reason, when the wheel moves up and down, a vertical force is input to the wheel, and the rubber bush is elastically deformed. Thereby, a camber angle and a toe angle may generate | occur | produce in a wheel by elastically deforming a rubber bush.

  In view of the above fact, an object of the present invention is to provide a vehicle suspension device that can suppress the influence of the elastic body on the rear wheel when the rear wheel moves up and down.

  The vehicle suspension device according to claim 1 is provided in a rear wheel support member that rotatably supports a rear wheel of the vehicle and the rear wheel support member, and is disposed on the vehicle front side of a wheel center of the rear wheel. The upper connection portion, and the rear wheel support member at a position on the vehicle lower side of the upper connection portion, arranged side by side with the upper connection portion in a side view and in the vehicle rear view. A lower connecting portion that is arranged offset to the tire ground contact center side with respect to the upper connecting portion, and provided on one side in the vehicle width direction with respect to the rear wheel, and the front end portion is rotatably connected to the vehicle body. The rear end portion is rotatably connected to the upper connection portion with an upper elastic body interposed therebetween, and the rotation axis at the front end portion and the rear end portion is set to an axis along the vehicle width direction in the vehicle rear view. The upper trailing link and the upper Provided on the vehicle lower side of the ring link, the front end portion is rotatably connected to the vehicle body, and the rear end portion is rotatably connected to the lower connection portion with the lower elastic body interposed therebetween. And a lower trailing link that is set to an axis that inclines toward the vehicle lower side as the rotation axis at the front end portion and the rear end portion moves toward one side in the vehicle width direction when viewed from the rear of the vehicle.

  In the vehicle suspension device according to the first aspect, the rear wheel is rotatably supported by the rear wheel support member. The rear wheel support member is provided with an upper connection portion and a lower connection portion, and the upper connection portion and the lower connection portion are disposed on the vehicle front side with respect to the wheel center of the rear wheel. The upper connecting portion and the lower connecting portion are arranged side by side in a side view, and the lower connecting portion is arranged offset to the tire ground contact center side with respect to the upper connecting portion in a vehicle rear view. Yes.

  An upper trailing link is provided on one side in the vehicle width direction with respect to the rear wheel. The front end portion of the upper trailing link is rotatably connected to the vehicle body, and the upper trailing link is rotatably connected to the upper connection portion with the upper elastic body interposed at the rear end portion. . And the rotational axis in the front-end part and rear-end part of an upper trailing link is set to the axis line along a vehicle width direction by vehicle rear surface view.

  Further, a lower trailing link is provided below the upper trailing link. That is, the lower trailing link is provided on one side in the vehicle width direction with respect to the rear wheel. The front end portion of the lower trailing link is rotatably connected to the vehicle body, and the lower trailing link is rotatable to the lower connection portion with the lower elastic body interposed at the rear end portion. It is connected to.

  Thereby, the virtual kingpin axis is set to be inclined to one side in the vehicle width direction toward the vehicle upper side in the vehicle rear view. When a vertical force is input to the rear wheel, the front ends of the upper and lower trailing links rotate with respect to the vehicle body, and the rear ends of the upper and lower trailing links It is rotated with respect to the rear wheel (rear wheel support member).

  Here, the rotational axis at the front end and the rear end of the lower trailing link is set to an axis that inclines toward the vehicle lower side toward the vehicle width direction one side as viewed from the rear of the vehicle. Thereby, it is possible to suppress the occurrence of a camber angle in the rear wheel when the vertical force is input to the rear wheel.

  In other words, if the rotation axes of the front and rear ends of the lower trailing link are set to axes along the vehicle width direction, the front ends of the upper and lower trailing links rotate relative to the vehicle body. Then, theoretically, the rear end portions of the upper trailing link and the lower trailing link move up and down with respect to the vehicle body. For this reason, the camber angle in the rear wheel does not occur.

  However, the rotational moment acts on the rear wheel support member by the vertical force input to the rear wheel. The moment force acts on the upper elastic body from the upper connecting portion of the rear wheel support member and also acts on the lower elastic body from the lower connection portion of the rear wheel support member. For this reason, the upper elastic body and the lower elastic body are elastically deformed, and the virtual kingpin shaft is inclined to one side in the vehicle width direction toward the vehicle upper side with respect to the set virtual kingpin shaft. As a result, a camber angle in the direction in which the upper part of the rear wheel falls to one side in the vehicle width direction (the upper trailing link and the lower trailing link side) is generated in the rear wheel.

  On the other hand, in the first aspect of the invention, the rotation axis at the front end portion and the rear end portion of the lower trailing link is set to an axis that inclines toward the vehicle lower side toward the one side in the vehicle width direction when viewed from the rear of the vehicle. Has been. For this reason, the rear end portion of the upper trailing link moves from the initial position to the vehicle upper side when viewed from the rear of the vehicle, but the rear end portion of the lower trailing link is obliquely tilted on one side in the vehicle width direction from the initial position when viewed from the rear of the vehicle. Move upward. Thus, when the rear wheel moves up and down with respect to the vehicle body, the virtual kingpin shaft moves toward the vehicle upper side with respect to the set virtual kingpin shaft, and the other side in the vehicle width direction (the upper trailing link and the lower side). Tilt to the opposite side of the trailing link. As a result, the rear wheel is inclined in a direction to cancel the camber angle generated by the elastic deformation of the upper elastic body and the lower elastic body as described above, so that the occurrence of the camber angle in the rear wheel can be suppressed. As described above, the influence on the rear wheel of the elastic body when the rear wheel moves up and down can be suppressed.

  A vehicle suspension device according to a second aspect is the vehicle suspension device according to the first aspect, wherein the vehicle suspension device is spanned between the vehicle body and the rear wheel support member, and a front end portion is rotatably connected to the vehicle body. And a control link that is rotatably connected to the rear wheel support member on the rear side of the wheel center with respect to the wheel center, and the control link is one side in the vehicle width direction toward the front side of the vehicle in plan view. In addition to being inclined toward the vehicle side, the vehicle is inclined toward the vehicle upper side toward the vehicle rear side in a side view with respect to the upper trailing link.

  In the vehicle suspension device according to the second aspect, the control link is bridged between the vehicle body and the rear wheel support member. The front end portion of the control link is rotatably connected to the vehicle body, and the rear end portion of the control link is rotatably connected to the rear wheel support member at a position on the vehicle rear side of the wheel center. Further, the control link is inclined to one side in the vehicle width direction as it goes to the vehicle front side in plan view.

  By the way, as described above, since the rotation axes of the front end portion and the rear end portion of the lower trailing link are inclined toward the vehicle lower side toward the one side in the vehicle width direction, the rear wheels move up and down with respect to the vehicle body. In doing so, the virtual kingpin axis tilts toward the other side in the vehicle width direction toward the vehicle upper side with respect to the set virtual kingpin axis. For this reason, the front end (the end on the virtual kingpin axis side) of the reference line that determines the toe angle of the rear wheel (the line viewed from the rear end of the control link to the virtual kingpin axis in plan view) in plan view is Move to one side in the vehicle width direction with respect to the initial position. That is, the reference line inclines toward one side in the vehicle width direction as it goes to the vehicle front side with respect to the initial position in plan view. As a result, a toe angle in a direction in which the front portion of the rear wheel is inclined toward one side in the vehicle width direction is generated in the rear wheel.

  Here, the control link is inclined with respect to the upper trailing link toward the vehicle upper side as it goes to the vehicle rear side in a side view. For this reason, when the rear wheel moves up and down, the rear end portion of the control link moves obliquely upward on one side in the vehicle width direction with respect to the initial position in the vehicle rear view. That is, the rear end portion of the control link moves to one side in the vehicle width direction as compared with the case where the control link is arranged in parallel with the upper trailing link in a side view. As a result, the control link acts so as to pull the rear portion of the rear wheel toward one side in the vehicle width direction, so that the rear wheel is tilted in a direction to cancel the toe angle generated in the rear wheel. Therefore, the toe angle generated at the rear wheel can be suppressed.

  As described above, according to the present invention, it is possible to suppress the influence of the elastic body on the rear wheel when the rear wheel moves up and down.

It is the perspective view seen from the vehicle left diagonal rear which shows the three-wheeled electric vehicle to which the vehicle suspension apparatus which concerns on this embodiment was applied. It is the perspective view seen from the vehicle left diagonal back which shows the vehicle suspension apparatus shown by FIG. It is the perspective view seen from the vehicle right diagonal front which shows the vehicle suspension apparatus shown by FIG. It is the side view seen from the vehicle left side which shows the vehicle suspension apparatus shown by FIG. FIG. 3 is a partially broken rear view of the vehicle suspension shown in FIG. 2 as seen from the vehicle rear side. FIG. 3 is a partially cutaway front view showing the vehicle suspension shown in FIG. 2 as viewed from the front side of the vehicle. It is sectional drawing which shows the structure of the periphery of the upper side rubber bush used for the vehicle suspension apparatus shown by FIG. (A) is the side view seen from the vehicle left side which shows the rotary damper used for the vehicle suspension apparatus shown by FIG. 2, (B) is a top view which shows the rotary damper of (A). It is the model seen from the vehicle rear side for demonstrating the camber angle which generate | occur | produces in a rear wheel when a rear wheel moves up and down with respect to a vehicle body, (A) is a figure which shows an initial state, (B ) Is a view showing a state in which the rear wheel moves up and down with respect to the vehicle body. FIG. 6 is a schematic diagram viewed from the upper side of the vehicle for explaining a toe angle generated in the rear wheel when the rear wheel moves up and down with respect to the vehicle body. FIG. FIG. 4 is a view showing a state in which the rear wheel moves up and down with respect to the vehicle body. FIG. 10 is a schematic diagram corresponding to FIG. 9 for explaining the effect of the control link shown in FIG. 2, (A) is a diagram showing an initial state, and (B) is a rear wheel that moves up and down relative to the vehicle body. It is a figure which shows the state which carried out.

  Hereinafter, a three-wheel electric vehicle 12 as a vehicle to which a vehicle suspension device 10 according to an embodiment of the present invention is applied will be described with reference to the drawings, and then the vehicle suspension device 10 will be described. It should be noted that arrow FR, arrow UP, arrow LH, arrow RH, and arrow OUT, which are appropriately shown in each figure, respectively indicate the front of the vehicle (traveling direction), the upper side of the vehicle, the left side of the vehicle, the right side of the vehicle, and the outward side of the vehicle width. ing. Hereinafter, when simply using the front-rear, left-right, and up-down directions, the front-rear direction in the vehicle front-rear direction, the left-right direction in the vehicle left-right direction, and the up-down direction in the vehicle up-down direction, unless otherwise specified.

  (About the configuration of the three-wheeled electric vehicle 12)

  FIG. 1 is a perspective view of a three-wheeled electric vehicle 12 to which a vehicle suspension device 10 according to this embodiment is applied. The three-wheeled electric vehicle 12 is a three-wheeled electric vehicle having two front wheels and one rear wheel, and is configured to drive the left and right front wheels 16 steered by the steering 14 by a driving force of a motor (not shown). A main frame 18 is provided on the vehicle rear side of the left and right front wheels 16. The main frame 18 is formed in a flat frame box shape from a material such as metal, and constitutes the skeleton of the vehicle body 20 of the three-wheeled electric vehicle 12. A rear frame 22 constituting a skeleton of the vehicle body 20 together with the main frame 18 is integrally fixed to the rear end portion of the main frame 18. The rear frame 22 includes a pair of upper and lower horizontal frame portions 24 and 26, and vertical frame portions 28, 30, and 32 that connect the upper and lower horizontal frame portions 24 and 26 in the vertical direction.

  As shown in FIGS. 2 to 6, the upper and lower horizontal frame portions 24 and 26 are formed by square pipes and extend along the vehicle width direction. Further, the vertical frame portion 28 disposed on the left end side of the vehicle is constituted by a pair of left and right connecting plates 34 and 36 arranged in the vehicle width direction. The left and right connecting plates 34 and 36 are formed in a U-shape (substantially U-shaped) with the opposite sides opened when viewed from the front-rear direction of the vehicle, and the left end sides of the upper and lower horizontal frame portions 24 and 26 are formed. It is connected vertically. Further, the vertical frame portion 30 disposed on the right end side of the vehicle is formed in a substantially U-shape (substantially U-shape) with the outer side in the vehicle width direction opened, and the upper and lower horizontal frame portions 24, 26 are arranged. The right end is connected vertically. Further, the vertical frame portion 32 disposed on the center side in the vehicle width direction is formed in a Japanese character shape (substantially B shape) when viewed from the front-rear direction of the vehicle, and the vehicle width of the upper and lower horizontal frame portions 24, 26. A portion on the left side of the central portion in the direction is connected in the vertical direction.

  (Configuration of vehicle suspension device 10)

  The vehicle suspension device 10 is provided between the rear frame 22 and the rear wheel 38 described above. The vehicle suspension device 10 includes a rear axle bracket 40 as a rear wheel support member that rotatably supports a rear wheel 38, an upper trailing link 50, an upper rubber bush 64 as an upper elastic body, and a lower trailing link. 70, a lower rubber bush 82 as a lower elastic body, a pair of left and right front rubber bushes 76, 86 as a front elastic body, a control link 100, a torsion bar (torsion shaft) 110, and a rotary damper 120 It is constituted by. Hereinafter, each component will be described.

  The rear axle bracket 40 includes a bracket body 42. The bracket body 42 is formed in a plate shape with a material such as metal, and is disposed with the plate thickness direction set in the vehicle width direction. A rear wheel 38A of the rear wheel 38 is rotatably attached to the bracket body 42 via an axle shaft (not shown), a hub 49 shown in FIG. Further, the bracket main body 42 is integrally provided with an upper connecting portion 44 and a lower connecting portion 46 for connecting an upper trailing link 50 and a lower trailing link 70, which will be described later, at a position opposite to the hub 49, respectively. Or it is provided integrally.

  The upper connecting portion 44 is located above the wheel center S (see FIG. 4) of the rear wheel 38 and on the vehicle front side. The upper connecting portion 44 extends from the upper end portion of the bracket body 42 to one side in the vehicle width direction (the side opposite to the hub 49) and is bent toward the vehicle front side at the intermediate portion. That is, the front end portion of the upper connecting portion 44 is disposed with the plate thickness direction as the vehicle width direction.

  As shown in FIG. 4, the lower connecting portion 46 is located on the lower side and the vehicle front side with respect to the wheel center S of the rear wheel 38. Further, the lower connecting portion 46 integrally extends downward from the lower end portion of the bracket main body 42 and is slightly inclined toward the other side in the vehicle width direction (hub 49 side) as it goes downward as viewed from the rear of the vehicle. And the upper side connection part 44 and the lower side connection part 46 are located in a line with the up-down direction by the vehicle side view shown by FIG. 4, and the lower side connection part 46 is higher than the upper connection part 44 by the vehicle rear view shown by FIG. Also, the rear wheel 38 is offset to the tire ground contact center C side.

  A rear extension 48 extends integrally from the rear end of the bracket body 42 toward the vehicle rear side. A connecting piece 48A is provided at the rear end of the rearward extending portion 48 so as to protrude toward one side in the vehicle width direction (the side opposite to the hub 49). The connecting piece 48A is disposed away from the wheel center S of the rear wheel 38 on the vehicle rear side, and corresponds to a control link 100 described later.

  The upper trailing link 50 is composed of an A arm made of a metal pipe or the like, and has a pair of left and right arm portions 52 and 54 branched toward the vehicle front side. One arm portion 52 extends in the vehicle front-rear direction, and a front end portion of the arm portion 52 is inserted between the lateral frame portions 24 and 26 of the rear frame 22. A cylindrical tubular portion 52A (see FIG. 6) whose axial direction is the vehicle width direction is integrally provided at the front end portion of the arm portion 52, and a bearing 56 is provided inside the tubular portion 52A. Is inserted. A connecting shaft 58 is fitted inside the inner ring of the bearing 56, and the connecting shaft 58 is fixed so as not to rotate relative to the vertical frame portion 32. The axis of the connecting shaft 58 is the first axis CL1 (corresponding to the rotational axis of the front end portion of the upper trailing link 50 in the present invention) (see FIG. 6), and the first axis CL1 is along the vehicle width direction. Are arranged. Further, a flange portion (large diameter portion) is provided at an intermediate portion in the axial direction of the connecting shaft 58, and the inner ring of the bearing 56 is supported by the flange portion. Further, a connecting member 60 is attached to one end of the cylindrical portion 52A in the axial direction (the end opposite to the vertical frame portion 32). The connecting member 60 is formed in a truncated cone shape whose diameter decreases toward the side opposite to the cylindrical portion 52A (here, the right side of the vehicle body), and is coaxially and integrally fixed to the cylindrical portion 52A. ing. A part of the connecting member 60 is inserted inside the cylindrical portion 52A, and the outer ring of the bearing 56 is supported by the part. Accordingly, the front end portion of the arm portion 52 is connected to the vehicle body 20 via the bearing 56 and is configured to be rotatable around the first axis CL <b> 1 of the connecting shaft 58.

  Further, as shown in FIG. 2, a damper mounting portion 62 is provided at the front end portion of the arm portion 52 on the vehicle rear side slightly from the cylindrical portion 52 </ b> A, and the damper mounting portion 62 extends from the arm portion 52. It protrudes to one side in the vehicle width direction (here, the vehicle left side). The damper mounting portion 62 corresponds to a rotary damper 120 described later.

  A bearing portion 52 </ b> B is integrally provided at the rear end portion of the arm portion 52. The bearing portion 52B is formed in a cylindrical shape whose axial direction is the vehicle width direction, and is located on the side of the upper coupling portion 44 of the rear axle bracket 40 (one side in the vehicle width direction).

  An upper rubber bush 64 is attached to the bearing portion 52B. The upper rubber bush 64 is formed of a rubber material, and includes a cylindrical main body portion 64A fitted inside the bearing portion 52B as shown in FIG. The main body 64A is divided into left and right at the axial center, and is configured to be fitted to the bearing 52B from both sides in the vehicle width direction. Flange portions 64B having substantially the same diameter as the bearing portions 52B are respectively provided at both axial ends of the main body portion 64A, and the bearing portions 52B are sandwiched from both sides in the vehicle width direction by these flange portions 64B.

  A connecting shaft 66 is inserted inside the upper rubber bush 64. The axis of the connecting shaft 66 is the second axis CL2 (corresponding to the rotational axis of the rear end portion of the upper trailing link 50 in the present invention), and the second axis CL2 is set parallel to the first axis CL1. ing. That is, the second axis CL2 is arranged along the vehicle width direction. Further, one end side in the axial direction of the connecting shaft 66 passes through the tip end portion of the upper connecting portion 44, and nuts are screwed into male screw portions formed at both ends in the axial direction of the connecting shaft 66. Accordingly, the rear end portion of the arm portion 42 is connected to the upper connection portion 44 via the upper rubber bush 64 and the connection shaft 66, and the arm portion 52 is connected to the rear axle bracket 40 with respect to the second axis CL2 of the connection shaft 66. It is configured to be rotatable around.

  The upper rubber bush 64 described above has a rigidity with respect to a lateral force (load in the vehicle width direction) acting on the rear wheel 38, and a longitudinal force (load in the vehicle longitudinal direction) acting on the rear wheel 38 or a vertical force (vehicle vertical). It is set lower than the rigidity with respect to the load in the direction, is easily deformed with respect to the lateral force, and is not easily deformed with respect to the longitudinal force and vertical force. This rigidity characteristic is set by, for example, the relationship between the thickness dimension (thickness) T1 of the main body 64A and the thickness dimension (thickness) T2 of the flange 46B.

  As shown in FIG. 2, the other arm portion 54 of the upper trailing link 50 is integrally joined to the rear end portion of the one arm portion 52 at the rear end portion. And the arm part 54 is inclined with respect to the vehicle front-rear direction so as to move away from the arm part 52 toward the front end side. Further, the front end portion of the arm portion 54 is bent toward the vehicle front side, and a ball joint 68 is attached to the front end portion of the arm portion 54. The ball joint 68 is inserted between the pair of connecting plates 34 and 36 of the vertical frame portion 28 and is connected to the vertical frame portion 28 by a connecting pin 69 (see FIG. 6) along the vehicle width direction. Thereby, the front end part of the arm part 54 is connected to the vehicle body 20 so as to be rotatable (rotatable up and down, left and right).

  On the other hand, the lower trailing link 70 is disposed below the upper trailing link 50. Similar to the upper trailing link 50, the lower trailing link 70 is configured by an A arm made of a metal pipe or the like, and has a pair of left and right arm portions 72 and 74 branched toward the vehicle front side. ing.

  One arm portion 72 extends in the vehicle front-rear direction below the arm portion 52 of the upper trailing link 50, and the front end portion of the arm portion 72 is positioned below the lateral frame portion 26 of the rear frame 22. . A cylindrical bearing portion 72A (see FIG. 6) is integrally provided at the front end portion of the arm portion 72, and the axis of the bearing portion 72A is directed to one side in the vehicle width direction (the vehicle left side) in the vehicle rear view. It is inclined downward as it goes. A front rubber bush 76 is attached to the bearing portion 72A as shown in FIG. The front rubber bush 76 has the same configuration as the upper rubber bush 64 described above, and is attached to the bearing portion 72 </ b> A by the same mounting method as the upper rubber bush 64. A pair of left and right brackets 78 are provided on both sides of the front rubber bush 90A in the vehicle width direction. These brackets 78 are made of sheet metal or the like bent in a substantially L shape, and are fastened and fixed to the lower surface of the horizontal frame portion 26. Furthermore, the side wall of each bracket 78 is arranged along the direction orthogonal to the axis of the bearing portion 72A corresponding to the bearing portion 72A. The connecting shaft 80 passes through the side walls of these brackets 78 in the axial direction of the bearing portion 72 </ b> A and is inserted into the front rubber bush 76. The axis of the connecting shaft 80 is a third axis CL3 (corresponding to the rotational axis of the front end portion of the lower trailing link 70 in the present invention) (see FIG. 6), and the third axis CL3 is a plan view of the vehicle. It is arranged parallel to the first axis CL1 and is inclined downward toward the one side in the vehicle width direction with respect to the first axis CL1 in the vehicle front view (vehicle rear view). Furthermore, male screw portions are provided at both ends in the axial direction of the connecting shaft 80, and the male screw portions protrude to the outside of the left and right brackets 78 (the side opposite to the front rubber bush 76). The connecting shaft 80 is fastened and fixed to the left and right brackets 78 by screwing nuts into these male screw portions. Accordingly, the front end portion of the arm portion 72 is connected to the vehicle body 20 via the connecting shaft 80 and is configured to be rotatable around the third axis CL3 of the connecting shaft 80.

  Further, the rear end portion of the arm portion 72 is disposed on the side (one side in the vehicle width direction) of the lower connecting portion 46 of the rear axle bracket 40. A cylindrical bearing portion 72B is integrally provided at the rear end portion of the arm portion 72, and the bearing portion 72B is disposed with the axial direction parallel to the third axis CL3. The bearing portion 72B has the same configuration as the bearing portion 52B described above, and a lower rubber bush 82 is attached to the bearing portion 72B. The lower rubber bushing 82 has the same configuration as the upper rubber bushing 64 described above, and is fastened and fixed to the lower coupling portion 46 via a coupling shaft 84 inserted on the inner side in the same manner as the upper rubber bushing 64. ing. The axis of the connecting shaft 84 is the fourth axis CL4 (corresponding to the rotational axis of the rear end portion of the lower trailing link 70 in the present invention) (see FIG. 5), and the fourth axis CL4 is the third axis. It is set in parallel with CL3. As a result, the rear end portion of the arm portion 72 is coupled to the lower coupling portion 46 via the lower rubber bush 82 and the coupling shaft 84, and around the fourth axis CL4 of the coupling shaft 84 with respect to the rear axle bracket 40. It is configured to be rotatable.

  As shown in FIG. 2, the other arm portion 74 of the lower trailing link 70 is positioned below the arm portion 54 of the upper trailing link 50, and the rear end portion of the arm portion 74 is the arm portion 72. It is joined to the rear end side. The arm portion 74 is inclined with respect to the vehicle front-rear direction so as to move away from one arm portion 72 toward the front end side in a vehicle plan view, and the front end portion of the arm portion 74 is bent toward the vehicle front side. Yes. A cylindrical bearing portion 74A is integrally provided at the front end portion of the arm portion 74. The bearing portion 74A is located below the lateral frame portion 26 of the rear frame 22 and is connected to the third axis CL3. It is arranged on the same axis. A front rubber bush 86 is attached to the bearing portion 74A as shown in FIG. The front rubber bush 86 has the same configuration as the above-described front rubber bush 76, and the bearing portion 74A is connected to the horizontal frame portion 26 via the front rubber bush 86, the left and right brackets 88, and the connecting shaft 90. ing. The bracket 88 and the connecting shaft 90 have the same configuration as the bracket 78 and the connecting shaft 80 described above, and the axis of the connecting shaft 90 coincides with the third axis CL3. Thus, the front end portion of the arm portion 74 is connected to the vehicle body 20 so as to be rotatable around the connecting shaft 90 (around the third axis CL3).

  Thus, in the present embodiment, the rear axle bracket 40 that rotatably supports the rear wheel 38 is connected to the vehicle body 20 via the upper trailing link 50 and the lower trailing link 70, and the double trailing link is provided. A suspension is constructed.

  On the other hand, the control link 100 includes a link body 102 formed in a long cylindrical shape, and a pair of ball joints 104 and 106 attached to both ends of the link body 102 in the longitudinal direction. One ball joint 104 is attached to the connecting piece 48A of the rear axle bracket 40 described above. Accordingly, one end portion (rear end portion) in the longitudinal direction of the control link 100 is rotatably connected to the rear axle bracket 40. The other ball joint 106 is attached to a bracket 108 attached to the horizontal frame portion 26. Accordingly, the other end portion (front end portion) in the longitudinal direction of the control link 100 is rotatably connected to the vehicle body 20.

  The bracket 108 described above extends from the longitudinal end portion (here, the left end portion of the vehicle) of the lateral frame portion 26 to the vehicle rear side. The control link 100 spanned between the bracket 108 and the connecting piece 48A of the rear axle bracket 40 is inclined toward the vehicle upper side as it goes to the vehicle rear side with respect to the upper trailing link 50 in a side view of the vehicle. The vehicle is inclined to one side in the vehicle width direction (here, the left side of the vehicle) as it goes to the front side of the vehicle in a plan view of the vehicle. Furthermore, the control link 100 is inclined to the vehicle upper side as it goes to the other side in the vehicle width direction when viewed from the rear of the vehicle.

  Here, as shown in FIG. 9A, the end point H (intersection with the ground) of the virtual kingpin axis K is set so as to pass through the tire ground contact center in the vehicle longitudinal direction, and the scrub of the rear wheel 38 is performed. The radius is set to zero.

  On the other hand, the torsion bar 110 is formed in a long cylindrical shape by spring steel, and is disposed between the horizontal frame portion 24 and the horizontal frame portion 26 with the axial direction being the vehicle width direction. The torsion bar 110 is disposed between the vertical frame portion 30 and the vertical frame portion 32 in front of the rear wheel 38 and the rear axle bracket 40 in the vehicle. One end of the torsion bar 110 in the axial direction (one end in the longitudinal direction) is connected to one end of the connecting member 60 in the axial direction (end on the reduced diameter side) so as not to be relatively rotatable by serration coupling. . As a result, one end of the torsion bar 110 in the axial direction is connected to the cylindrical portion 52 </ b> A (the front end of the arm portion 52) of the upper trailing link 50 through the connecting member 60 so as to be integral and relatively non-rotatable.

  The other end portion in the axial direction (the other end portion in the longitudinal direction) of the torsion bar 110 is connected to the vertical frame portion 30 via the connecting member 112. The connecting member 112 is formed in a cylindrical shape whose axial direction is the vehicle width direction. Moreover, the axial direction one end side of the connection member 112 is rotatably fitted in the circular hole formed in the vertical frame part 30, as FIG. 6 shows. Thereby, the connecting member 112 is rotatably attached to the vertical frame portion 30. Further, one end of the connecting member 112 in the axial direction is integrally coupled with the other end in the axial direction of the torsion bar 110 fitted inside. As a result, the other axial end of the torsion bar 110 and the connecting member 112 are connected so as not to rotate relative to each other, and the other axial end of the torsion bar 110 is connected to the vehicle body 20 via the connecting member 112. .

  Further, as shown in FIG. 3, a claw portion 112 </ b> A that protrudes downward (radially outward) is provided on the outer peripheral portion of the connecting member 112 on the other axial end side. The front end portion of the adjusting bolt 114 attached to the lower end portion of the vertical frame portion 30 is in contact with the claw portion 112A from the vehicle rear side. The adjustment bolt 114 is disposed with the axial direction set in the vehicle front-rear direction, and is screwed into a female screw portion formed at the lower end portion of the vertical frame portion 30. Then, relative rotation of the connecting member 112, that is, the other end in the axial direction of the torsion bar 110 relative to the vertical frame portion 30 around the axis (in the direction of arrow A in FIG. 3) is restricted by the adjusting bolt 114.

  On the other hand, the rotary damper 120 has a vertical frame portion on the side opposite to the torsion bar 110 (one longitudinal end side of the torsion bar 110) via the front end portion (tubular portion 52A) of the arm portion 52 of the upper trailing link 50. 28 and the vertical frame portion 32. The rotary damper 120 has a movable portion 122 fixed to the upper trailing link 50 and a fixed portion 126 fixed to the vehicle body 20 (connected so as not to be displaced).

  As shown in FIGS. 8A and 8B, the movable portion 122 includes a movable side plate 124 formed in a long shape by a sheet metal. The movable side plate 124 is disposed so that the plate thickness direction is the vehicle width direction and the longitudinal direction is along the longitudinal direction of the upper trailing link 50 (substantially the vehicle longitudinal direction). The rear portion 124A of the movable plate 124 is fastened and fixed to the tip end portion of the above-described damper mounting portion 62 (see FIG. 2) by a pair of front and rear bolts.

  The fixed portion 126 includes four fixed-side plates 128, 130, 132, and 134 formed in a substantially disc shape (here, a teardrop shape) by sheet metal. These fixed side plates 128, 130, 132, 134 are arranged with the plate thickness direction in the vehicle width direction. Between the fixed side plate 128 and the fixed side plate 130, a pair of friction plates 136 and 138 formed between the front side of the movable side plate 124 and a disc shape are sandwiched, and the fixed side plate 132. A pair of friction plates 140 and 142 formed in a disc shape are sandwiched between the fixed plate 134 and the fixed side plate 134. These friction plates 136, 138, 140, 142 are fixed to the fixed side plates 128, 130, 132, 134.

  Bolts 144 pass through substantially the center portions of the fixed side plates 128, 130, 132, and 134, the front portion 124B of the movable plate 124, and the substantially center portions of the friction plates 136, 138, 140, and 142. The front end side of the bolt 144 is inserted into the washer 146 and is screwed into the pair of nuts 148 and 150. The bolt 144 is arranged with the axial direction as the vehicle width direction, and is located coaxially with the first axis CL1 of the connecting shaft 58 that is the rotation center of the upper trailing link 50 with respect to the vehicle body 20 and the torsion bar 110. ing.

  Also, between the head 144A of the bolt 144 and the fixed side plate 130, and between the washer 146 and the fixed side plate 132, disc spring-like springs 152, 154 formed in a substantially star shape by a spring material are provided. Intervene. As a result, the front portion 124B of the movable plate 124 and the friction plates 136 and 138 are elastically sandwiched between the fixed plates 128 and 130, and the friction plates 140 and 142 are elastic between the fixed plates 132 and 134. The movable side plate 124 is integrally connected to the friction plates 136, 138, 140, and 142 and is connected to the fixed side plates 128, 130, 132, and 134 so as to be relatively rotatable around the bolt 144.

  Further, the front end portions of the fixed side plates 130 and 128 are joined together, and the front end portions of the fixed side plates 132 and 134 are joined together. Each of these joint portions is formed with a circular through hole 156 (see FIG. 8A), and each through hole 156 has an axis of a support pin 158 (see FIG. 3) formed in a cylindrical shape. One end of the direction is inserted. The support pin 158 is arranged with the axial direction along the vehicle width direction, and the other axial end is fixed to a bracket 160 (see FIG. 3) attached to the vertical frame portion 32. Thereby, relative rotation around the bolt 144 with respect to the vehicle body 20 of the fixed side plates 128, 130, 132, 134 is restricted.

  In the rotary damper 120 configured as described above, when the upper trailing link 50 rotates up and down (swings) with respect to the vehicle body 20 about the first axis CL1, the movable side of the movable portion 122 coupled to the upper trailing link 50 is movable. The plate 124 rotates relative to the fixed side plates 128, 130, 132, 134 and the friction plates 136, 138, 140, 142 around the bolt 144. As a result, the friction plates 136, 138, 140, 142 and the movable plate 124 come into sliding contact with each other, and a frictional force (damping force) is generated. As a result, the relative rotation of the movable portion 122 with respect to the fixed portion 126, that is, the swing of the upper trailing link 50 with respect to the vehicle body 20 is attenuated. In addition, the frictional force can be arbitrarily adjusted by changing the tightening torque (elastic deformation amount) of the springs 152 and 154 with the bolt 144 and the nuts 148 and 150.

  (Function and effect)

  Next, the operation and effect of this embodiment will be described.

  In the vehicle suspension device 10 configured as described above, the rear wheel 38 is rotatably supported by the rear axle bracket 40, and the rear axle bracket 40 is connected to the vehicle body via the upper trailing link 50 and the lower trailing link 70. 20 is connected. Thereby, the vehicle suspension apparatus 10 is configured as a double trailing link type suspension.

  When the rear wheel 38 moves up and down with respect to the vehicle body 20, the front end of the upper trailing link 50 rotates about the first axis CL1, and the front end of the lower trailing link 70 is third. It rotates around the axis CL3. At this time, the torsion bar 110 is torsionally deformed with the rotation of the upper trailing link 50 to absorb the impact, and the rotary damper 120 attenuates the relative rotation of the movable portion 122 with respect to the fixed portion 126 to thereby reduce the rear wheel. The vertical movement (vibration) of 38 is attenuated.

  Here, the third axis line CL3 and the fourth axis line CL4 are inclined toward the vehicle lower side toward the one side in the vehicle width direction when viewed from the rear of the vehicle. That is, the third axis CL3 and the fourth axis CL4 are inclined downward toward the one side in the vehicle width direction with respect to the first axis CL1 and the second axis CL2 in the vehicle rear view. Thereby, it is possible to suppress the occurrence of a camber angle in the rear wheel 38 when the rear wheel 38 moves up and down with respect to the vehicle body 20.

  This will be described in detail. That is, if the third axis CL3 is arranged in parallel with the first axis CL1, a parallel link is configured by the upper trailing link 50 and the lower trailing link 70. For this reason, when the front end portions of the upper trailing link 50 and the lower trailing link 70 rotate around the first axis CL1 and the third axis as the rear wheel 38 moves up and down with respect to the vehicle body 20, the upper trailing link is rotated. The rear end portions of the link 50 and the lower trailing link 70 are respectively rotated with respect to the rear wheel 38 and are moved up and down with respect to the vehicle body 20 in the rear view of the vehicle. Therefore, theoretically, no camber angle is generated in the rear wheel 38.

  However, a rotational moment is applied to the bracket body 42 by the vertical force input to the rear wheel 38 (see arrow M in FIG. 7). The moment force acts on the upper rubber bush 64 from the upper connecting portion 44 of the bracket body 42 via the connecting shaft 66, and from the lower connecting portion 46 of the bracket body 42 via the connecting shaft 84 to the lower rubber. It acts on the bush 82. For this reason, the upper rubber bush 64 and the lower rubber bush 82 are elastically deformed, and when the rear wheel 38 moves up and down, the virtual kingpin axis K moves toward the vehicle upper side with respect to the set virtual kingpin axis K. Tilt to one side in the width direction. As a result, a camber angle is generated in the rear wheel 38 in a direction in which the upper portion of the rear wheel 38 falls to one side in the vehicle width direction (the arrow B direction side in FIG. 9A).

  On the other hand, in the present embodiment, the third axis CL3 and the fourth axis CL4 are inclined downward toward the one side in the vehicle width direction when viewed from the rear of the vehicle. For this reason, the rear end portion of the upper trailing link 50 moves from the initial position to the vehicle upper side (arrow C direction side in FIG. 9A) in the rear view of the vehicle, but the rear end portion of the lower trailing link 70 Moves diagonally upward (in the direction of arrow D in FIG. 9A) from the initial position to one side in the vehicle width direction when viewed from the rear of the vehicle. As a result, when the rear wheel 38 moves up and down, the virtual kingpin axis K tilts to the other side in the vehicle width direction (the direction of arrow E in FIG. 9B) with respect to the set virtual kingpin axis K. As a result, the rear wheel 38 inclines in a direction to cancel the camber angle generated by the elastic deformation of the upper rubber bush 64 and the lower rubber bush 82 as described above (see FIG. 9B). The occurrence of the camber angle in can be suppressed. Therefore, the influence on the rear wheel 38 of the upper rubber bush 64 and the lower rubber bush 82 when the rear wheel 38 moves up and down can be suppressed.

  Further, as described above, the virtual kingpin axis K is set when the rear wheel 38 moves up and down by the third axis CL3 and the fourth axis CL4 being inclined toward the vehicle lower side as it goes toward the vehicle width direction one side. The vehicle tilts toward the other side in the vehicle width direction toward the upper side of the vehicle with respect to the virtual kingpin axis K. For this reason, the front end (virtual kingpin axis K) of the reference line CV (the line viewed from the rear end of the control link 100 to the virtual kingpin axis K in the plan view) that determines the toe angle of the rear wheel 38 in plan view. Side end) moves to one side in the vehicle width direction with respect to the initial position (see FIGS. 10A and 10B). That is, the reference line CV is inclined to one side in the vehicle width direction as it goes to the vehicle front side with respect to the initial position in plan view. As a result, a toe angle is generated in the rear wheel 38 in such a direction that the front portion of the rear wheel 38 is tilted to one side in the vehicle width direction when the rear wheel 38 moves up and down (see FIG. 10B).

  Here, the control link 100 is inclined with respect to the upper trailing link 50 toward the vehicle upper side as it goes toward the vehicle rear side as viewed from the side of the vehicle. For this reason, when the rear wheel 38 moves up and down, the rear end portion of the control link 100 moves obliquely upward on one side in the vehicle width direction with respect to the initial position in the vehicle rear view (arrow F in FIG. 11B). Direction side). That is, the rear end portion of the control link 100 moves to one side in the vehicle width direction as compared with the case where the control link 100 is arranged in parallel with the upper trailing link 50 in a side view. As a result, the control link 100 acts to pull the rear portion of the rear wheel 38 toward one side in the vehicle width direction. As a result, the rear wheel 38 is tilted in a direction to cancel the toe angle generated at the rear wheel 38 described above (see FIG. 11B), so that the toe angle generated at the rear wheel 38 can be suppressed. As described above, the influence on the rear wheel 38 of the upper rubber bush 64 and the lower rubber bush 82 when the rear wheel 38 moves up and down can be suppressed.

  In the present embodiment, the configuration is such that the end point H (intersection with the ground) of the virtual kingpin axis K passes through the tire ground contact center in the vehicle longitudinal direction view (the scrub radius of the rear wheel 38 is set to zero). However, the present invention is not limited to this, and a configuration in which the end point H of the virtual kingpin axis K is disposed close to the tire ground contact center in the vehicle front-rear direction view (the scrub radius of the rear wheel 38 approaches zero). Configuration).

  In the present embodiment, the front end portions of the left and right arm portions 72 and 74 of the lower trailing link 70 are connected to the vehicle body 20 via the front rubber bushes 76 and 54 (both are front elastic bodies). However, the present invention is not limited to this, and the front end portion of the lower trailing link may be connected to the vehicle body without using the front elastic body.

  Further, in the present embodiment, the upper rubber bush 64 (upper elastic body) and the lower rubber bush 82 (lower elastic body) act on the rear wheel 38 rather than the rigidity with respect to the longitudinal force acting on the rear wheel 38. Although the configuration is such that the rigidity against the force is set low, the present invention is not limited to this, and the rigidity of the upper elastic body and the lower elastic body can be changed as appropriate.

  In the present embodiment, the upper trailing link 50 and the lower trailing link 70 are arranged on the left side of the vehicle with respect to the rear wheel 38. You may arrange | position on the vehicle right side with respect to the wheel 38. FIG. In this case, the right side of the vehicle is one side in the vehicle width direction of the present invention.

  Furthermore, in the present embodiment, the vehicle suspension device 10 is applied to the rear wheel 38 of the three-wheel electric vehicle 12, but the vehicle suspension device 10 may be applied to the rear wheel of a four-wheel vehicle.

  In addition, the present invention can be implemented with various modifications without departing from the scope of the invention. It goes without saying that the scope of rights of the present invention is not limited to the above embodiment.

10 Vehicle suspension system 12 Three-wheeled electric vehicle (vehicle)
20 Car body 38 Rear wheel 40 Rear axle bracket (rear wheel support member)
44 Upper connection part 46 Lower connection part 50 Upper trailing link 64 Upper rubber bush (upper elastic body)
70 Lower Trailing Link 82 Lower Rubber Bush (Lower Elastic Body)
100 Control link CL1 First axis (axis)
CL2 2nd axis (axis)
CL3 3rd axis (axis)
CL4 4th axis (axis)

Claims (2)

A rear wheel support member for rotatably supporting the rear wheel of the vehicle;
An upper connecting portion provided on the rear wheel support member and disposed on the vehicle front side of a wheel center of the rear wheel;
Provided on the rear wheel support member at a position on the vehicle lower side of the upper connecting portion, arranged side by side with the upper connecting portion in a vertical direction in a side view, and tires with respect to the upper connecting portion in a vehicle rear view A lower connecting portion arranged offset to the ground center side;
Provided on one side in the vehicle width direction with respect to the rear wheel, the front end is rotatably connected to the vehicle body, and is rotatably connected to the upper connecting portion with the upper elastic body interposed at the rear end. An upper trailing link in which the rotation axis at the front end and the rear end is set to an axis along the vehicle width direction in the vehicle rear view;
Provided on the vehicle lower side of the upper trailing link, the front end is rotatably connected to the vehicle body, and is rotatable to the lower connecting portion with a lower elastic body interposed at the rear end. A lower trailing link that is connected and set to an axis that inclines toward the vehicle lower side as the rotation axis at the front end and the rear end is directed to one side in the vehicle width direction when viewed from the rear of the vehicle;
A vehicle suspension system comprising: It spans between the vehicle body and the rear wheel support member, the front end portion is rotatably connected to the vehicle body, and the rear end portion rotates to the rear wheel support member on the vehicle rear side from the wheel center. It has a control link that is freely connected,
The control link is inclined to one side in the vehicle width direction as it goes to the vehicle front side in a plan view, and is inclined to the upper side of the vehicle toward the vehicle rear side in a side view with respect to the upper trailing link. Item 4. The vehicle suspension device according to Item 1.

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