JP2008201307A - Stabilizer device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a stabilizer device capable of providing proper roll rigidity corresponding to a traveling state of a vehicle with a simple constitution. <P>SOLUTION: This stabilizer device 100 has a pair of arm parts 112 respectively connected via a link 120 to a spring lower part 21 of a suspension device respectively arranged in right-left wheels, a stabilizer bar 110 connecting these arm parts, substantially extending in the car width direction and having an intermediate part 111 formed of an elastic material, and a stabilizer bush 130 supporting the intermediate part 111 via an elastic body by a car body and arranged in a plurality of places separated in the car width direction, and is constituted so that the elastic body of the stabilizer bush 130 is formed of a rubber-based material of a high loss material, and has a nonlinear characteristic of increasing a spring constant to a load inputted via the link 120 at a stroke of the suspension deice in response to an increase in the load. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a stabilizer device that controls the roll rigidity of a vehicle such as an automobile.

  A stabilizer device provided in a suspension device of a vehicle such as an automobile connects the unsprung portions of the left and right suspensions with a stabilizer bar that is a kind of torsion spring formed using a material having elasticity such as spring steel, The middle part is fixed to the vehicle body side. Such a stabilizer device can improve the roll rigidity without changing the spring constant of the suspension spring, and is useful for improving the steering stability of the vehicle.

The stabilizer bar is attached to the vehicle body via a stabilizer bush having an elastic body such as a rubber-based material for vibration isolation or the like.
Conventionally, in order to achieve both steering stability and riding comfort, it has been known to provide recesses extending in the axial direction on the top and bottom surfaces of a vibration-proof rubber body of a stabilizer bush (see, for example, Patent Document 1).
Similarly, to achieve both steering stability and ride comfort, a space is formed between the stabilizer bush and the vehicle body when the left and right suspensions are in the same phase, and a portion of the stabilizer bush is inserted into the inserted portion of the vehicle body or the like in the reverse phase state. There is known a structure in which a stabilizer bush is restrained to the vehicle body side (see, for example, Patent Document 2).

In addition, it is known that the roll characteristics required for the vehicle are not constant and differ depending on the traveling state. For example, in a state where the roll angle is large as in emergency avoidance, in order to improve the anti-overturning characteristic or prevent the vehicle from being understeered and preventing spin etc., the roll rigidity is increased, especially the front roll rigidity is set to the rear. On the other hand, it is required to raise relatively. On the other hand, when the roll rigidity is high at a small steering angle in normal travel, the ground load on the turning inner wheel side is reduced, and the cornering force of the left and right front wheels is reduced, resulting in low vehicle responsiveness.
On the other hand, an active stabilizer device that varies the roll rigidity of the vehicle using an actuator according to the traveling state of the vehicle is known (see, for example, Patent Document 3).
JP-A-2005-212780 JP 2006-144837 A Japanese Patent Laid-Open No. 2006-219048

However, the above-described active stabilizer device has a complicated structure and it is difficult to ensure reliability, and is accompanied by an increase in vehicle weight, power consumption, cost, and the like.
An object of the present invention is to provide a stabilizer device that can obtain an appropriate roll rigidity according to the traveling state of a vehicle with a simple configuration.

The present invention solves the above-described problems by the following means.
According to the first aspect of the present invention, a pair of arm portions respectively connected via a link to unsprung portions of suspension devices respectively provided on the left and right wheels, and the pair of arm portions are coupled to each other in the vehicle width direction. And a stabilizer bar having an intermediate portion formed of an elastic material, and supporting the intermediate portion of the stabilizer bar via the elastic body with respect to the vehicle body, and spaced apart in the vehicle width direction. In the stabilizer device provided with the stabilizer bushes provided at a plurality of locations, the elastic body of the stabilizer bush is formed of a rubber material of a high loss material, and when the suspension device is rebounded and bumped via the link The spring constant with respect to the input load has a nonlinear characteristic that increases as the load increases. It is a Biraiza apparatus.

The invention according to claim 2 is the stabilizer device according to claim 1, wherein the rubber-based material forming the elastic body of the stabilizer bush includes SBR-based rubber.
According to a third aspect of the present invention, in the stabilizer device according to the first or second aspect, the stabilizer bush is respectively provided in an upper region and a lower region along the input direction of the load as viewed from a central axis of the stabilizer bar. It is arrange | positioned, It is a stabilizer apparatus provided with the space part formed between the inside of the said elastic body, or the said elastic body and the supporting member which supports this elastic body.
According to a fourth aspect of the present invention, in the stabilizer device according to any one of the first to third aspects, the elastic body of the stabilizer bush is made of a material of the elastic body in a region compressed by the load. The stabilizer device is characterized in that a hard member made of a material having higher hardness is embedded.

According to a fifth aspect of the present invention, there is provided a stabilizer device including a front wheel stabilizer device provided in the front wheel suspension and a rear wheel stabilizer device provided in the rear wheel suspension, wherein the front wheel stabilizer device comprises: A stabilizer device according to any one of claims 1 to 4, wherein the rear wheel stabilizer device is connected to a pair of unsprung portions of a suspension device provided on each of the left and right wheels via a link. And a stabilizer bar that connects the pair of arm portions and extends substantially along the vehicle width direction and has an intermediate portion formed of an elastic material, and the intermediate portion of the stabilizer bar The stabilizer bushes are provided at a plurality of locations separated from each other in the vehicle width direction. The stabilizer bush of the front wheel stabilizer device has a rate of increase of the spring constant in the input direction of the load accompanying an increase in the roll angle of the vehicle as the roll angle of the stabilizer bush of the rear wheel stabilizer device increases. It is a stabilizer device characterized by being larger than the rate of increase of the spring constant.
According to a sixth aspect of the present invention, in the stabilizer device according to the fifth aspect, the stabilizer bush of the front wheel stabilizer device has the rear constant in the initial roll state in which the spring constant in the load input direction is small and the roll angle of the vehicle is small. It is substantially the same as or smaller than the stabilizer bush of the wheel stabilizer device, and is larger than the stabilizer bush of the rear wheel stabilizer device in the transient and steady roll state in which the roll angle is larger than the initial roll state. It is a stabilizer device.

According to the present invention, the following effects can be obtained.
(1) When the vehicle is turning, the left and right arm portions of the stabilizer bar receive an input downward via a link on the inner ring side (rebound side) and upward on the outer ring side (bump side). At this time, if the intermediate portion of the stabilizer bar is restrained in the vertical direction by the stabilizer bush, the intermediate portion is twisted to function as a torsion bar spring, and the roll rigidity of the vehicle is improved.
However, in the case of the present invention, since the spring constant of the elastic body of the stabilizer bush has a non-linear characteristic that increases with an increase in load, the spring of the stabilizer bush in the initial roll region where the roll angle of the vehicle is small. By reducing the constant and inclining the intermediate portion of the stabilizer bar with respect to the vehicle body, the twist can be reduced, the effect of improving the roll rigidity can be suppressed, and the effectiveness of the stabilizer device can be weakened. As a result, the roll rigidity of the vehicle at the initial stage of the roll is lowered, so that the ground contact load of the inner ring can be increased at the beginning of turning or at a minute steering angle, and the cornering force in the inner ring and the outer ring can be improved. Further, it is possible to improve the yaw response of the vehicle and the turning ability at the beginning of turning.
In this specification, claims, etc., the spring constant of the bush (elastic body) is the load along the longitudinal direction (axial direction) of the stabilizer link from the stabilizer bar in a state where the bush is restrained with respect to the vehicle body. The value obtained by dividing this load by the displacement in the load direction of the stabilizer bar when is input. Further, the spring constant here refers to a dynamic spring constant obtained by adding the influence of damping of the elastic body to the static spring constant unless otherwise specified.
In addition, even when running straight ahead, the ride comfort during minute inputs in which the left and right suspensions are displaced in opposite phases, such as when one wheel gets over a minute protrusion or descends into a minute recess on the road surface. Can be improved.

  In addition, since the elastic body of the stabilizer bush has a non-linear characteristic in which the spring constant with respect to the load increases as the load increases, the vertical displacement of the stabilizer bar is restricted when the roll angle of the vehicle increases and the load increases. As a result, twisting of the intermediate portion occurs, the roll rigidity of the vehicle is improved, and the anti-roll effect is generated. For this reason, the roll rigidity can be effectively improved in a state where the vehicle roll angle is large, such as in a steady turning state or sudden turning for avoiding danger, and the vehicle stability, rollover resistance, etc. can be ensured. Can do.

  Furthermore, since the elastic body of the stabilizer bush is formed of a high-loss material containing, for example, SBR rubber, the elastic body has a large damping force (loss) generated during deformation, and the frequency dependence of this damping force is also strong. As the roll frequency increases, the dynamic spring constant increases. As a result, for example, when the roll frequency is high, such as at a small steering angle or sudden turning during high-speed driving, the stabilizer bar is firmly restrained by the elastic body even at the same roll angle, so the earlier The torsional reaction force of the stabilizer bar can be generated to improve the roll rigidity of the vehicle and improve the stability of the vehicle.

(2) The stabilizer bush is disposed in each of the upper and lower regions along the load input direction when viewed from the central axis of the stabilizer bar, and is provided between the elastic body or the elastic body and a support member that supports the elastic body. By providing the space portion formed therebetween, the spring constant of the elastic body can be reduced by deforming the elastic body so as to crush the space portion during the initial stroke. When the load further increases, the space portion is crushed to generate a so-called stopper contact, and the spring constant of the elastic body with respect to the load can be increased nonlinearly.

(3) The elastic body of the stabilizer bush may have a nonlinear characteristic appropriately in the spring constant by embedding a hard member made of a material having a hardness higher than that of the elastic body in a region compressed by a load. And the above-described effects can be surely exhibited.

(4) In the stabilizer bush of the front wheel stabilizer device, the rate of increase of the spring constant in the input direction of the load accompanying the increase in the roll angle of the vehicle is the rate of increase of the spring constant accompanying the increase in the roll angle of the stabilizer bush of the rear wheel stabilizer device. Therefore, at the time of danger avoidance with a large roll angle or steady cornering, the anti-roll effect by the stabilizer device can be increased by strengthening the restraint of the stabilizer bar on the front wheel side with respect to the rear wheel side. Thus, by raising the roll rigidity on the front wheel side relative to the roll rigidity on the rear wheel side, so-called roll understeer can be generated and the steering stability of the vehicle can be shaken to the stable side, oversteer, spin, Dangerous behavior such as rollover can be suppressed.

(5) The stabilizer bush of the front wheel stabilizer device has a spring constant in the load input direction that is substantially the same as or smaller than the stabilizer bush of the rear wheel stabilizer device in the initial roll state, and is increased in the steady roll state. The transient roll stiffness at the initial stage of roll (small roll angle) can be relatively increased from the front wheel side to the rear wheel side, and the vehicle stability factor can be reduced to improve the turning performance and the micro rudder response. . On the other hand, in the later stage of the roll (roll angle is large), the roll rigidity on the front wheel side is higher than that on the rear wheel side, and the stability of the vehicle can be ensured.

  The object of the present invention is to provide a stabilizer device capable of obtaining an appropriate roll rigidity in accordance with the running state of a vehicle with a simple configuration. The stabilizer bush for supporting the intermediate portion of the stabilizer bar is made of a high-loss rubber such as an SBR system. The problem was solved by providing a straight portion that hits the stopper with a load greater than or equal to a predetermined value at the top and bottom of the base material.

Hereinafter, a first embodiment of a stabilizer device to which the present invention is applied will be described.
FIG. 1 is an exploded perspective view of a front suspension device including the stabilizer device according to the first embodiment.
In the first embodiment, the vehicle provided with the stabilizer device is an automobile such as a passenger car, for example, and the front suspension device is of the McPherson strut type.

The front suspension device includes a housing 10, a strut assembly 20, and a lower arm 30, and the lower arm 30 is attached to a vehicle body (not shown) via a cross member 40.
Further, the front suspension device includes a stabilizer device 100.

  The housing 10 accommodates a hub bearing that rotatably supports a front wheel (not shown), and is formed, for example, by performing predetermined machining on a steel casting.

The strut assembly 20 is an assembly of a strut 21, a spring 22, and an upper mount 23.
The strut 21 includes a shock absorber (damper) that is a hydraulic shock absorber, and is disposed in a state where a piston rod protrudes above the shell case. A housing bracket 21a to which the upper end of the housing 10 is fixed is provided at the lower end of the shell case. In addition, a spring seat 21 b is formed on the upper portion of the shell case so as to project from the outer peripheral surface of the shell case in a brim shape and hold the lower end portion of the spring 22.
Further, a stabilizer bracket 21c is provided below the spring seat 21b of the strut 21. The stabilizer bracket 21c is formed so as to protrude from the outer peripheral surface to the vehicle body rear side and to which a stabilizer link 120 described later is attached.

The spring 22 is a coil spring made of spring steel, for example, and the upper portion of the strut 21 is inserted into the inner diameter side of the spring 22. The spring 22 has a lower end held by the spring seat 21 b of the strut 21 and an upper end held by the spring seat of the upper mount 23.
The upper mount 23 is fixed to the vehicle body and holds the upper end portion of the piston rod of the strut 21 and the upper end portion of the spring 22, and the strut 21 and the spring 22 can be rotated around the kingpin axis together with the housing 10 when steering the front wheel. Rolling bearings are provided.

  The lower arm 30 is an L-shaped lower arm formed by, for example, a steel press, and is connected to the lower end of the housing 10 via a ball joint 31. On the vehicle body side, a cross member 40, a front bush 32, a rear bush 33 is connected. The lower arm 30 is supported so as to be swingable with respect to the cross member 40 about a central axis substantially coincident with a straight line connecting the center portions of the front bush 32 and the rear bush 33.

  The cross member 40 is a structural member serving as a base portion to which the lower arm 30 and the stabilizer device 100 are attached. For example, the cross member 40 is provided below the main frame (not shown) extending in the front-rear direction of the vehicle along both sides of the engine room (not shown). Fixed.

The stabilizer device 100 is an anti-roll device that improves the roll rigidity of the vehicle by using the spring reaction force of the stabilizer bar that connects the left and right suspensions.
The stabilizer device 100 includes a stabilizer bar 110, a stabilizer link 120, a stabilizer bush 130, and a clamp 140.

The stabilizer bar 110 is integrally formed, for example, by bending a spring steel wire, and includes an intermediate portion 111 and an arm portion 112.
The intermediate part 111 is a part extending substantially along the vehicle width direction.
The arm portion 112 is a portion formed to project obliquely forward from both end portions of the intermediate portion 111, and is curved to prevent interference with each member of the suspension device.

  The stabilizer link 120 is a rod-shaped member that connects the distal end portion of the arm portion 112 of the stabilizer bar 110 and the stabilizer bracket 21c of the strut 21 and is disposed so as to extend substantially in the vertical direction. The stabilizer link 120 is provided with a pair of ball joints at both ends, and can swing with respect to the stabilizer bar 110 and the strut 21. When the stabilizer device 100 is in operation, a direction connecting the swing center points of the pair of ball joints is an input direction D from the suspension to the stabilizer bar 110 (see FIG. 3).

The stabilizer bush 130 supports the intermediate portion 111 of the stabilizer bar 110 and is fixed to the upper surface portion of the cross member 40 by a clamp 140. The stabilizer bush 130 is made of, for example, a high-loss rubber material such as an SBR type in which the attenuation (loss) characteristic has a strong frequency dependency.
FIG. 2 is a side view of the stabilizer bush 130 viewed from the vehicle width direction.
The stabilizer bush 130 has a flat mounting surface portion 131 at the bottom, and is formed in an arch shape from the front surface portion 132 to the upper surface portion 133 and the rear surface portion 134 in a shape viewed from the vehicle width direction. When the stabilizer bush 130 is used, the attachment surface portion 131 contacts the upper surface portion of the cross member 40, and the front surface portion 132, the upper surface portion 133, and the rear surface portion 134 contact the inner surface of the clamp 140. Further, the front surface portion 132, the upper surface portion 133, and the rear surface portion 134 are formed at both end portions in the vehicle width direction so as to protrude from these surface portions in a stepped manner, and the rib portions 135 that prevent the stabilizer bush 130 from coming off from the clamp 140 are formed. Is formed.

The stabilizer bush 130 includes an opening 136 and straight portions 137 and 138.
The opening 136 is a circular through hole into which the intermediate portion 111 of the stabilizer bar 110 is inserted.
The straight portion 137 is formed by recessing the central portion of the upper surface portion 133 in the vehicle width direction and the front-rear direction in a tray shape. Thus, a space is formed between the inner surface of the clamp 140 in a no-load state (a state where the vehicle is not rolled).
The straight portion 138 is formed by recessing the central portion of the attachment surface portion 131 in the vehicle width direction and the front-rear direction in a tray shape. As a result, a space is formed between the upper surface of the cross member 40 in a no-load state when attached to the vehicle body.
The straight portions 137 and 138 are arranged so that the central portions thereof substantially coincide with the direction along the input direction D when viewed from the central axis of the intermediate portion 111 of the stabilizer bar 110.

  Further, the rubber thickness L1 between the straight portion 137 and the opening 136 in the input direction D and the rubber thickness L2 between the opening 136 and the straight portion 138 are the support points that are input from the stabilizer bar 110 to the stabilizer bush 130. It is set appropriately according to the load. If these rubber thicknesses L1 and L2 are reduced, the spring constant at the initial stroke is lowered, so that the difference in spring constant after the straight portions 137 and 138 are crushed and the stopper hits increases, and the non-linear characteristics are obtained. It can be strengthened.

FIG. 3 is a graph showing the correlation between the load along the input direction D of the stabilizer bush described above and the displacement of the stabilizer bar with respect to this load.
In FIG. 3, the horizontal axis indicates the displacement amount of the stabilizer bar 110, the right side indicates the bump side (suspension side of the suspension), and the left side indicates the rebound side (suspension side of the suspension). The vertical axis shows the load, the upper side shows the bump side load, and the lower side shows the rebound side load.
In addition, for example, the characteristics in a region where the roll frequency is relatively low and the maximum load is large as in steady cornering in normal running are indicated by solid lines, and the roll frequency is relatively high and the maximum load is high as in emergency avoidance. The characteristics in a large area are indicated by broken lines. In addition, the characteristics in the region where the roll frequency is low and the maximum load is small as in the case of a small rudder angle during low-speed driving are indicated by a one-dot chain line. The characteristics in a region where is small are indicated by a two-dot chain line.

As shown in FIG. 3, in the region A where the displacement at the initial stage of the roll or the like is relatively small, the relationship between the displacement and the load is almost linear, and the spring constant in the load direction of the stabilizer bush 130 is almost constant. ing. In the regions B and C where the load and displacement are large with respect to this region, the spring constant of the stabilizer bush 130 increases nonlinearly. Such a tendency is common regardless of the roll frequency.
On the other hand, focusing on the change in characteristics due to the roll frequency, when the roll frequency is high, the amount of displacement for the same load is reduced due to the loss caused by the deformation of the rubber, compared to when the roll frequency is low, and the apparent spring constant (static spring constant) It can be seen that the dynamic spring constant (which takes into account the effects of loss) is increasing.
Here, the area of the portion surrounded by the curves indicating the respective characteristics in FIG. 3 represents the magnitude of the loss generated in the rubber, and it can be seen that the loss increases as the roll frequency increases.

  The clamp 140 fixes the stabilizer bush 130 to the upper surface portion of the cross member 40. The clamp 140 is formed of, for example, a sheet metal, and has a U-shape with a lower side opened when viewed from the vehicle width direction. Etc. are adapted to the shape of the front, upper and rear surfaces of the stabilizer bush 130. Further, a flange portion is formed having a bolt hole protruding from the opening end portion (lower end portion) in the front-rear direction of the vehicle and into which a bolt for fastening the clamp 140 to the cross member 40 is inserted.

According to the first embodiment described above, the following effects can be obtained.
Since the spring constant of the stabilizer bush 130 with respect to the load input along the input direction D from the stabilizer bar 110 has a non-linear characteristic that increases as the load increases, the initial roll region where the roll angle of the vehicle is small. (Area A in FIG. 3), the spring constant of the stabilizer bush 130 is reduced to incline the intermediate portion 111 of the stabilizer bar 110 with respect to the vehicle body, thereby reducing the twist of the intermediate portion 111 and improving the roll rigidity. It can suppress and the effect of the stabilizer apparatus 100 can be weakened. As a result, the roll rigidity of the vehicle at the initial stage of the roll is lowered, so that the ground contact load of the inner ring can be increased at the beginning of turning or at a minute steering angle, and the cornering force in the inner ring and the outer ring can be improved. Further, it is possible to improve the yaw response of the vehicle and the turning ability at the beginning of turning.
In addition, even when running straight ahead, the ride comfort during minute inputs in which the left and right suspensions are displaced in opposite phases, such as when one wheel gets over a minute protrusion or descends into a minute recess on the road surface. Can be improved.

  Further, the stabilizer bush 130 has a non-linear characteristic in which the spring constant with respect to the load from the stabilizer bar 110 increases as the load increases, so that the steady roll region (FIG. 3) in which the roll angle of the vehicle increases and the load increases. In the regions B and C), the vertical displacement of the stabilizer bar 110 is restrained, the twist of the intermediate portion 111 is generated, the roll rigidity of the vehicle is improved, and the anti-roll effect is generated. For this reason, roll rigidity can be effectively improved in a state where the roll angle of the vehicle is large, such as in a steady turning state or sudden turning for avoiding danger, and vehicle stability, rollover resistance, and the like can be ensured.

  Furthermore, since the stabilizer bush 130 is made of a high-loss material including SBR rubber, the damping force (loss) generated at the time of deformation is large, and the frequency dependence of this damping force is strong, so the roll frequency is fast. Then, the dynamic spring constant increases. As a result, for example, when the roll frequency is high, such as at a minute steering angle or sudden turning during high-speed driving, the stabilizer bar 110 is more restrained by the stabilizer bush 130 even at the same roll angle, so that the speed is faster. It is possible to improve the roll rigidity of the vehicle by generating a torsional reaction force at the intermediate portion 111 of the stabilizer bar 110 from the time, and to improve the stability of the vehicle.

  Further, the stabilizer bush 130 is provided with the straight portions 137 and 138, and in a region where the load and displacement are small, the space portion of the straight portions 137 and 138 is deformed so as to be crushed, whereby the spring of the stabilizer bush 130 is obtained. The constant can be lowered, the load and displacement are increased, the space is completely crushed, and when the so-called stopper hits, the spring constant increases rapidly, so the above-mentioned nonlinear characteristics can be obtained reliably. .

Next, a second embodiment of the stabilizer device to which the present invention is applied will be described.
Note that, in each embodiment described below, portions that are substantially the same as those of the previous embodiments are denoted by the same reference numerals, description thereof is omitted, and differences are mainly described.
The stabilizer device according to the second embodiment includes a stabilizer bush 230 described below instead of the stabilizer bush 130 according to the first embodiment.

FIG. 4 is a side view of the stabilizer bush 230 as seen from the vehicle width direction.
The stabilizer bush 230 is attached to a mounting target surface portion facing the front side of the vehicle on the vehicle body side, and has a planar mounting surface portion 231 that extends substantially in the vertical direction and is opposed to the mounting target surface portion. Have.
Further, the upper surface portion 232, the front surface portion 233, and the lower surface portion 234 are arched in a continuous shape as viewed from the vehicle width direction, like the front surface portion 132, the upper surface portion 133, and the rear surface portion 134 of the stabilizer bush 130 of the first embodiment. It is formed to become.
At both ends of the upper surface portion 232, the front surface portion 233, and the lower surface portion 234 in the vehicle width direction, rib portions 235 are formed so as to protrude from these surface portions in a stepped manner.

Further, the stabilizer bush 230 includes an opening 236 into which the intermediate portion 111 of the stabilizer bar 110 is inserted, and straight portions 237 and 238 described below.
The straight portion 237 and the straight portion 238 are formed by denting the central portions of the upper surface portion 232 and the lower surface portion 234 in the vehicle width direction and the front-rear direction, respectively, in a tray shape. Thereby, in a no-load state, a space portion is formed between the opposing surface portions of the clamp 140.
The rubber thickness L1 between the straight portion 237 and the opening 236 along the input direction D and the rubber thickness L2 between the opening 236 and the straight portion 238 are set in the same manner as L1 and L2 in the first embodiment. Is done.
Also in the second embodiment described above, the same effects as those of the first embodiment described above can be obtained.

Next, a third embodiment of the stabilizer device to which the present invention is applied will be described.
The stabilizer device according to the third embodiment includes a stabilizer bush 330 described below instead of the stabilizer bush 130 according to the first embodiment.
FIG. 5 is a side view of the stabilizer bush 330 viewed from the vehicle width direction.
Stabilizer bush 330 is provided with straight portions 337 and 338 described below in place of straight portions 137 and 138 in stabilizer bush 130 of the first embodiment.

  The straight portions 337 and 338 are respectively disposed above and below the opening 136 and formed as openings that penetrate the stabilizer bush 330 in the vehicle width direction. The straight portions 337 and 338 are formed in an arc shape that is substantially concentric with the opening 136 when viewed from the vehicle width direction, and the central portion in the circumferential direction is substantially along the input direction D when viewed from the center of the opening 136. Arranged above and below the direction, respectively.

Here, the rubber thicknesses L1 and L2 including the upper and lower straight portions 337 and 338 of the opening 136 along the input direction D are set according to the support point load input from the stabilizer bar 110 to the stabilizer bush 330. However, it is normally set so that L1 <L2. Further, the widths L3 and L4 of the straight portions 337 and 338 along the input direction D and the width L5 of the straight portions 337 and 338 in the direction perpendicular to the input direction D and the longitudinal direction of the intermediate portion 111 of the stabilizer bar 110 are respectively The stabilizer bush 330 is appropriately set so as to obtain the characteristics described in FIG.
Also in the third embodiment described above, the same effect as in the first embodiment described above can be obtained.

Next, a fourth embodiment of the stabilizer device to which the present invention is applied will be described.
The stabilizer device of the fourth embodiment includes a front (front wheel) suspension similar to that of the first embodiment, a front (front wheel) stabilizer device provided on a rear (rear wheel) suspension (not shown), and a rear (rear wheel). ) It consists of a stabilizer device. The rear stabilizer device is configured in substantially the same manner as the front stabilizer device, and includes a stabilizer bar connected to the unsprung portion of the rear suspension via a stabilizer link, and a stabilizer bush that supports the stabilizer bar with respect to the vehicle body. ing.

The front stabilizer device includes a stabilizer bush 430 described below instead of the stabilizer bush 130 of the first embodiment.
FIG. 6 is a side view of the stabilizer bush 430 as seen from the vehicle width direction.
The stabilizer bush 430 is provided with intermediate plates (interleaf) 439 and 440 described below on the stabilizer bush 130 of the first embodiment.

The intermediate plates 439 and 440 are formed of a material having a higher hardness than the rubber material constituting the stabilizer bush 730 main body, such as a metal plate, and are vulcanized and bonded to the rubber material by in-mold molding when the stabilizer bush 730 is vulcanized. Has been.
The intermediate plates 439 and 440 are formed in a circular arc shape that is substantially concentric with the opening 136 when viewed from the vehicle width direction, and the central portion in the circumferential direction is a direction substantially along the input direction D when viewed from the center of the opening 136. It is arrange | positioned at the upper side and lower side, respectively.
On the other hand, the same thing as the stabilizer bush 130 of Example 1 is used for the stabilizer bush of a rear stabilizer apparatus.
The load that the stabilizer bush 130 for the rear wheels receives from the stabilizer bar along the input direction D is substantially the same as the load that the stabilizer bush 430 for the front wheels receives from the stabilizer bar 110 when the roll angle of the vehicle is the same. Is set to

FIG. 7 is a graph showing the correlation between the load along the input direction D of the front and rear stabilizer bushes and the displacement of the stabilizer bar with respect to this load.
In FIG. 7, the horizontal axis indicates the amount of displacement of the stabilizer bar, the right side indicates the bump side (suspension side of the suspension), and the left side indicates the rebound side (suspension side of the suspension). The vertical axis shows the load, the upper side shows the bump side load, and the lower side shows the rebound side load.
Moreover, the characteristic in the state where the roll frequency of the stabilizer bush 430 for front wheels is low is shown by the solid line, and the characteristic in the state where the roll frequency is high is shown by the broken line. Further, the characteristic of the rear wheel stabilizer bush 130 in a state where the roll frequency is low is indicated by a one-dot chain line, and the characteristic in a state where the roll frequency is high is indicated by a two-dot chain line.

  As shown in FIG. 7, in the initial roll region A with a relatively small roll angle, the front wheel stabilizer bush 430 and the rear wheel stabilizer bush 130 have substantially the same spring constant. However, when the steady roll region B has a larger roll angle than the initial roll region A, the space formed in the straight portions of the stabilizer bushes 430 and 130 is crushed to generate a so-called stopper contact, and the spring constant becomes nonlinear. To increase. At this time, since the rate of increase of the spring constant of the stabilizer bush 430 for the front wheels is larger than the rate of increase of the spring constant of the stabilizer bush 130 for the rear wheels, in this steady roll region B, the stabilizer bush 430 for the front wheels. The spring constant is higher than that of the stabilizer bush 130 for the rear wheel. Such a tendency is common when the roll frequency is low and when the roll frequency is high. However, when the roll frequency is high, loss due to deformation of the rubber increases, so that the spring constants of the stabilizer bushes 430 and 130 are both It is larger than when the roll frequency is low.

According to the fourth embodiment described above, the front wheel stabilizer bush 430 has an increase rate of the spring constant in the load input direction D accompanying an increase in the roll angle of the vehicle, and the spring constant of the rear wheel stabilizer bush 130 increases. Since the ratio is larger than the ratio, the anti-roll effect by the stabilizer device 100 can be increased by strengthening the restraint of the stabilizer bar 110 on the front wheel side with respect to the rear wheel side at the time of danger avoidance with a large roll angle or steady cornering. Thus, by raising the roll rigidity on the front wheel side relative to the roll rigidity on the rear wheel side, it is possible to generate so-called roll understeer and swing the steering stability of the vehicle to the stable side, oversteer, spin, Dangerous behavior such as rollover can be suppressed.
Further, when the roll frequency is increased, the dynamic spring constant is increased due to the loss of rubber, and the above-described characteristics are further enhanced, so that the stability of the vehicle can be further improved.

  In addition, the spring constant of the stabilizer bush 430 for the front wheels is substantially the same as that of the stabilizer bush 130 for the rear wheels in the initial roll state, and is increased in the steady roll state, so that the transient roll stiffness at the initial stage of the roll is increased from the front wheel side. It can be relatively increased on the wheel side, and the stability factor of the vehicle can be reduced to improve the turning performance and the micro rudder response. On the other hand, in the latter stage of rolling, the roll rigidity on the front wheel side can be relatively increased as compared with that on the rear wheel side to ensure the stability of the vehicle.

(Modification)
The present invention is not limited to the embodiments described above, and various modifications and changes are possible, and these are also within the technical scope of the present invention.
(1) In each embodiment, the longitudinal direction (input direction) of the stabilizer link is substantially vertical, and the stabilizer bush has different spring constants in the initial stroke area on the upper side and lower side of the stabilizer bar. If the link is tilted and the input direction is also tilted accordingly, the shape of the stabilizer bush and the intermediate plate so that the spring constant in the direction along the tilt direction has the above-mentioned nonlinear characteristics, etc. It is good to set the arrangement of the above.
FIG. 8 is a schematic side view of the stabilizer device in which the stabilizer link is inclined and viewed from the vehicle width direction. In the stabilizer device 100 of FIG. 8, the stabilizer link 120 is arranged so as to be inclined so that the upper end portion is on the vehicle front side with respect to the lower end portion, the upper end portion is connected to the arm portion 112, and the lower end portion is connected to a lower arm (not shown). Since it is connected, the input direction D is also inclined similarly to the stabilizer link 120. In this case, it is preferable to provide a straight portion at a position along the input direction D inclined with respect to the stabilizer bar 100, or to dispose a hard member such as an intermediate plate.
(2) In each embodiment, the stabilizer link is connected to the strut. However, the present invention is not limited to this, and the stabilizer link may be connected to any of the unsprung portions of the suspension such as a suspension arm such as a lower arm and a housing.
(3) In Example 4, the spring constants of the front and rear wheel stabilizer bushes in the initial roll state were substantially the same. However, in the initial roll state, the rear wheel stabilizer bushes were the front wheel stabilizer bushes. The spring constant may be higher than that, and the front and rear spring constants may be reversed when the steady roll state is reached. According to this, the stability factor of the vehicle in the initial roll state can be further reduced, and the turning ability and responsiveness of the vehicle can be further improved.
Actually, the load that the stabilizer bush receives is a change in the lever ratio that accompanies the mounting position of the stabilizer link to the suspension device, the arm length and shape of the stabilizer bar, the placement of the stabilizer link, etc., even if the roll angle is constant. Therefore, the load input to the front and rear wheel stabilizer bushes may be different. Even in this case, if the rate of increase of the spring constant in the steady roll state relative to the spring constant in the initial roll state is made larger on the front wheel side than on the rear wheel side, the above-described effect of the present invention can be obtained. Can do.
(4) In Example 4, the difference in the characteristics of the front and rear stabilizer bushes is determined depending on the presence or absence of the intermediate plate. However, the present invention is not limited to this. You may make it give the difference of a characteristic.

It is a disassembled perspective view of the front suspension apparatus provided with Example 1 of the stabilizer apparatus to which the present invention is applied. It is the side view which looked at the stabilizer bush in the stabilizer apparatus of FIG. 1 from the vehicle width direction. It is a graph which shows the correlation characteristic of the load and displacement of the stabilizer bush of FIG. It is the side view which looked at the stabilizer bush in Example 2 of the stabilizer apparatus to which this invention was applied from the vehicle width direction. It is the side view which looked at the stabilizer bush in Example 3 of the stabilizer apparatus to which this invention was applied from the vehicle width direction. It is the side view which looked at the stabilizer bush of the front stabilizer apparatus in Example 4 of the stabilizer apparatus to which this invention is applied from the vehicle width direction. It is a graph which shows the correlation characteristic of the load and displacement of the stabilizer bush for the front wheel of Example 1, and a rear stabilizer apparatus. It is the typical side view which looked at the stabilizer apparatus with which the stabilizer link inclined and was seen from the vehicle width direction.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Housing 20 Strut assembly 21 Strut 22 Spring 23 Upper mount 30 Lower arm 31 Ball joint 32 Front bush 33 Rear bush 40 Cross member 100 Stabilizer device 110 Stabilizer bar 111 Intermediate part 112 Arm part 120 Stabilizer link 130 Stabilizer bush 131 Front part 132 133 Upper surface portion 134 Rear surface portion 135 Rib portion 136 Opening 137 Curled portion 138 Curled portion 140 Clamp

Claims (6)

A pair of arm portions respectively connected via a link to unsprung portions of the suspension devices provided on the left and right wheels respectively, and the pair of arm portions are connected to extend substantially along the vehicle width direction. A stabilizer bar having an intermediate portion formed of an elastic material;
A stabilizer device comprising: an intermediate portion of the stabilizer bar supported via an elastic body with respect to the vehicle body; and stabilizer bushes provided at a plurality of locations separated in a vehicle width direction.
The elastic body of the stabilizer bush is formed of a high-loss rubber-based material, and a spring constant with respect to a load input via the link at the time of rebounding and bumping of the suspension device increases as the load increases. A stabilizer device characterized by having a non-linear characteristic. The stabilizer device according to claim 1,
The stabilizer device, wherein the rubber material forming the elastic body of the stabilizer bush includes SBR rubber. In the stabilizer device according to claim 1 or 2,
The stabilizer bush is disposed in an upper region and a lower region along the load input direction as viewed from the central axis of the stabilizer bar, and supports the inside of the elastic body or the elastic body and the elastic body. A stabilizer device comprising a space formed between the two. In the stabilizer device according to any one of claims 1 to 3,
The stabilizer device, wherein the elastic body of the stabilizer bush is embedded with a hard member made of a material having a hardness higher than that of the elastic body in a region compressed by the load. In the stabilizer device comprising the front wheel stabilizer device provided in the front wheel suspension and the rear wheel stabilizer device provided in the rear wheel suspension,
The front wheel stabilizer device is the stabilizer device according to any one of claims 1 to 4,
The rear wheel stabilizer device includes a pair of arm portions respectively connected via a link to unsprung portions of suspension devices provided on left and right wheels, and the pair of arm portions coupled to each other. A stabilizer bar having an intermediate portion that extends substantially along the direction and is formed of an elastic material, and supports the intermediate portion of the stabilizer bar via the elastic body with respect to the vehicle body in the vehicle width direction. With stabilizer bushes provided at a plurality of spaced locations,
In the stabilizer bush of the front wheel stabilizer device, the rate of increase of the spring constant in the input direction of the load accompanying the increase in the roll angle of the vehicle is the same as that of the stabilizer bush of the rear wheel stabilizer device. A stabilizer device characterized by being larger than the rate of increase. The stabilizer device according to claim 5, wherein
The stabilizer bush of the front wheel stabilizer device has a spring constant in the input direction of the load that is substantially the same as or smaller than the stabilizer bush of the rear wheel stabilizer device in the initial roll state where the roll angle of the vehicle is small. A stabilizer device characterized in that in a transient and steady roll state where the roll angle is larger than the state, the stabilizer wheel is larger than the stabilizer bush of the rear wheel stabilizer device.

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