JP2004217069A - Supporting structure of suspension unit and steering unit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide the supporting structure of a suspension unit and a steering unit, which offers a linear compliance steer without being restricted by layout or the like. <P>SOLUTION: The rigidity of a bush 6, via which a transverse link 2 is supported on a vehicle body, and of an insulator 7, via which a steering gear box 5 is supported on the vehicle body, is made to have a non-linear characteristic composed of a low rigidity area (measure against sound vibration) for a small lateral force and a high rigidity area for a large lateral force (steering stability). Respective compliance steering angles corresponding to respective rigidity areas are calculated using the elastic modulus of each elastic material, i.e, the bush 6 and the insulator 7, and the elastic modulus of each elastic material is determined so as to make the compliance steering angles continuous with each other. When calculating the compliance steering angles, the quantity of a direct deformation due to the lateral force F and the quantity of a deformation due to a moment generated around a king pin shaft by the lateral force F, are considered. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

【００１４】
従って、横力Ｆにより直接変形されるブッシュの変形量ｘ_Ｂ１は下記３式、インシュレータの変形量ｘ_Ｉ１は下記４式で表れる。
【００１５】
【数２】

【００１６】
次に、キングピン軸ｋの傾き、所謂キャスタ角をθとしたとき、横力Ｆによってキングピン軸ｋ周りに発生するモーメントＭは下記５式で表れる。
【００１７】
【数３】

【００１８】
このモーメントＭのうち、コンプライアンスステアに関与するモーメント成分、即ち車輪中心を通る鉛直軸周りのモーメント成分Ｍ_Ｚ を取り出すと、下記６式で表れる。
【００１９】
【数４】

【００２０】
従って、このモーメント成分Ｍ_Ｚ によるブッシュの変形量ｘ_Ｂ２は下記７式、インシュレータの変形量ｘ_Ｉ２は下記８式で表れる。
【００２１】
【数５】

【００２２】
このキングピン軸ｋ周りのモーメントＭ（モーメント成分Ｍ_Ｚ ）によるブッシュの変形量ｘ_Ｂ２及びインシュレータの変形量ｘ_Ｉ２と、前記横力Ｆにより直接変形されるブッシュの変形量ｘ_Ｂ１及びインシュレータの変形量ｘ_Ｉ１とを考慮して、車輪のステア角δを算出すると、下記９式が得られる。
【００２３】
【数６】

【００２４】
所望するコンプライアンスステアの特性は、前記図３に示すように、横力Ｆに対してリニアなものであるから、前記低剛性域と高剛性域との境界点で車輪のステア角が同じになる必要がある。従って、前記９式に、前記ブッシュの低剛性域の弾性係数Ｋ_ＢＬ、高剛性域の弾性係数Ｋ_ＢＨ、インシュレータの低剛性域の弾性係数Ｋ_ＩＬ、高剛性域の弾性係数Ｋ_ＩＨを代入し、下記１０式を満足するように、各弾性体の弾性係数を求めればよい。
【００２５】
【数７】

【００２６】
このように本実施形態の懸架装置及び操舵装置の支持構造によれば、懸架装置のうち、車両幅方向又は略幅方向に配設されたリンク部材、即ちトランスバースリンク２を弾性体であるブッシュ６で車体に支持し、操舵装置のうち、ステアリングギヤボックス５を弾性体であるインシュレータ７で車体に支持すると共に、この懸架装置で懸架され且つ前記操舵装置に連結された車輪１のコンプライアンスステア（ステア角δ）が横力Ｆに対して線形特性を維持するように、ブッシュ６の剛性（弾性係数Ｋ_Ｂ ）及びインシュレータ７の剛性（弾性係数Ｋ_Ｉ ）設定するようにしたため、レイアウトなどの規制を受けることなく、車輪のコンプライアンスステアをリニアに設定することができる。
【００２７】
また、前記ブッシュ６及びインシュレータ７が、夫々、横力が小さなときに横力に対する剛性が小さい低剛性域と、横力が大きなときに横力に対する剛性が大きい高剛性域とを有する非線形な特性としたため、直進状態又は略直進状態におけるロードノイズやシミー等の音振減少を低減すると共に、横力の大きな旋回状態でキャンバ剛性を高めて応答性を良好にし、操縦安定性を向上させることができる。
【００２８】
また、前記低剛性域のコンプライアンスステア（ステア角δ）と前記高剛性域のコンプライアンスステア（ステア角δ）とが同じになるようにブッシュ６及びインシュレータ７の車両幅方向への剛性（弾性係数Ｋ_ＢＬ、Ｋ_ＢＨ、Ｋ_ＩＬ、Ｋ_ＩＨ）を設定するようにしたため、横力に対するコンプライアンスステア特性をブッシュ６及びインシュレータ７の低剛性域から高剛性域まで、つまり横力の小さな状態から大きな状態まで連続してリニアなものとすることができる。
【００２９】
また、横力Ｆにより直接変形するブッシュ６及びインシュレータ７の変形量ｘ_Ｂ１、ｘ_Ｉ１と、横力Ｆによって発生するキングピン軸回りのモーメントＭにより変形するブッシュ６及びインシュレータ７の変形量ｘ_Ｂ２、ｘ_Ｉ２とに基づいて、当該ブッシュ６及びインシュレータ７の剛性（弾性係数Ｋ_ＢＬ、Ｋ_ＢＨ、Ｋ_ＩＬ、Ｋ_ＩＨ）を設定するようにしたため、所望するブッシュ６及びインシュレータ７の剛性を正確に設定することができる。
【図面の簡単な説明】
【図１】本発明の懸架装置及び操舵装置の支持構造の一実施形態を示すものであり、（ａ）は平面図、（ｂ）は正面図である。
【図２】図１のブッシュ及びインシュレータに求められる横力に対する剛性の特性説明図である。
【図３】図１の車輪に求められる横力に対するコンプライアンスステアの特性説明図である。
【符号の説明】
１は車輪
２はトランスバースリンク
３はテンションロッド
４はタイロッド
５はステアリングギヤボックス
６はブッシュ
７はインシュレータ[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a support structure for a suspension device and a steering device of a vehicle, and is particularly suitable for supporting a link member of the suspension device and a steering gear box of the steering device via an elastic body.
[0002]
[Prior art]
In order to obtain linear steering characteristics from the straight running state to the turning state, the compliance steer of the suspension must be linear between lateral force and between the outer cylinder and the inner cylinder of the elastic support device of the steering gear box. It has been proposed to form a cavity (for example, Patent Document 1).
[0003]
[Patent Document 1]
JP-A-11-208487 [0004]
[Problems to be solved by the invention]
However, in order to form a cavity between the outer cylinder and the inner cylinder of the elastic support device of the steering gear box, the elastic support device needs to have a certain size. The size may not be obtained, and as a result, the compliance steer of the suspension may not have a linear characteristic with respect to the lateral force.
[0005]
The present invention has been developed to solve these problems, and does not require the size of the elastic support device, and makes the compliance steer of the suspension as linear as possible to the lateral force. It is an object of the present invention to provide a suspension device and a support structure of a steering device that are capable of performing the following.
[0006]
[Means for Solving the Problems]
In order to solve the above-described problems, the support structure of the suspension device and the steering device according to the present invention includes a link support elastic body that supports a link member disposed in a vehicle width direction or a substantially width direction to a vehicle body in the suspension device. A steering support elastic body for supporting a steering gear box on a vehicle body of the steering device, and a compliance steer of a wheel suspended by the suspension device and connected to the steering device maintains a linear characteristic with respect to a lateral force. The rigidity of the link support elastic body and the steering support elastic body in the vehicle width direction is set in such a manner as to achieve the above.
[0007]
【The invention's effect】
Thus, according to the support structure of the suspension device and the steering device of the present invention, the link support elastic member that supports the link member disposed in the vehicle width direction or approximately the width direction to the vehicle body, A steering support elastic body for supporting a steering gear box on a vehicle body, wherein a compliance steer of a wheel suspended by the suspension device and connected to the steering device maintains a linear characteristic with respect to a lateral force. Since the rigidity of the link support elastic body and the steering support elastic body in the vehicle width direction is set, it is possible to make the compliance steer of the wheels linear only by setting the rigidity of the two elastic bodies. Not regulated.
[0008]
BEST MODE FOR CARRYING OUT THE INVENTION
Next, an embodiment of a support structure of a suspension device and a steering device according to the present invention will be described in detail with reference to the drawings.
FIG. 1 shows a first embodiment of a support structure of a suspension device and a steering device of the present invention. Reference numeral 1 in the figure is a wheel suspended by the suspension device of the present embodiment and steered by the steering device. This wheel 1 is suspended by a transverse link 2 which is a kind of lateral link. The lateral link is a link member that is disposed in the vehicle width direction or substantially in the width direction and supports the lateral force of the wheel. Incidentally, reference numeral 3 in the figure is a tension rod. The wheel 1 is connected to a steering gear box 5 via a tie rod 4.
[0009]
The transverse link 2 is connected to a vehicle body via a bush 6 that is an elastic body. The steering gear box 5 is connected to a vehicle body via an insulator 7 which is an elastic body. The rigidity of the bush 6 and the insulator 7, specifically, the elastic coefficient is set as follows.
In general, the bush 6 connecting the transverse link 2 to the vehicle body is required to have a reduced road noise and camber rigidity. Therefore, in order to reduce road noise, it is desirable that rigidity be small when lateral force is small, and that rigidity be large when lateral force is large due to camber rigidity. When the displacement x is plotted on the horizontal axis and the lateral force F is plotted on the vertical axis, the lateral force-displacement characteristic of the bush 6 becomes a non-linear characteristic as shown in FIG. 3A. Here, when the lateral force is small, the region with low rigidity is defined as the low rigidity region, when the lateral force is large, the region with high rigidity is defined as the high rigidity region, the elastic coefficient of the low rigidity region is K _BL , and the elasticity of the high rigidity region is KBL. _{Let the} coefficient be _KBH .
[0010]
On the other hand, the insulator 7 that connects the steering gear box 5 to the vehicle body is required to reduce shimmy and provide steering stability. Therefore, in order to reduce shimmy, it is desirable that the rigidity be small when the lateral force is small, and it is desirable that the rigidity be large when the lateral force is large for steering stability. Similarly, when the displacement x is plotted on the horizontal axis and the lateral force F is plotted on the vertical axis, the lateral force-displacement characteristic of the insulator 7 also becomes a non-linear characteristic as shown in FIG. 3B. Again, when the lateral force is small, the region with small rigidity is defined as the low rigidity region, when the lateral force is large, the region with large rigidity is defined as the high rigidity region, the elastic coefficient of the low rigidity region is _KIL , and the elasticity of the high rigidity region is KIL. _{Let the} coefficient be _KIH .
[0011]
On the other hand, it is desired that the compliance steer δ with respect to the lateral force F is linear as shown in FIG. This is because, for example, at the time of transition from the straight traveling state to the turning state, the steering characteristic changes linearly.
By the way, when examining the compliance steer against the lateral force, first, the deformation amount of the bush and the insulator directly deformed by the lateral force and the deformation amount of the bush and the insulator deformed by the moment around the kingpin axis generated by the lateral force are considered. It needs to be considered. Now, o is the center of the wheel 1, n is the point of application to the wheel, m is the contact point of the kingpin axis k, and the vehicle plane view distance from the wheel center o to the application point n, the so-called pneumatic trail, is L ₃ , plan view of the vehicle distance from the center o to the kingpin axis ground point m, the so-called caster trail and L _4. Further, the distance in plan view of the vehicle from the wheel contact point n to the bush 6 is L ₁ , and the distance in plan view of the vehicle from the wheel contact point n to the steering gear box 5 (equivalent to the distance to the insulator 7) is L _2. And
[0012]
K _B on behalf of the modulus of elasticity of the _bush, when the K _I on behalf of the modulus of elasticity of the insulator, the force F _B is the following one set of the bush of the lateral force F, the force F _I according to the insulator below 2 It is expressed by an equation.
[0013]
(Equation 1)

[0014]
Accordingly, deformation amount of the bushing to be deformed directly by the lateral force F x _B1 is below three expressions, the deformation amount x _I1 of insulators appears below Equation 4.
[0015]
(Equation 2)

[0016]
Next, assuming that the inclination of the kingpin axis k, that is, the so-called caster angle, is θ, the moment M generated around the kingpin axis k by the lateral force F is expressed by the following equation (5).
[0017]
[Equation 3]

[0018]
Of this moment M, moment components involved in compliance steer, that is, taken out moment component M _Z around the vertical axis passing through the wheel center, appear in equation (6) below.
[0019]
(Equation 4)

[0020]
Therefore, the deformation amount _{x B2} is below 7 Expression of the bush by the moment component _{M Z,} deformation amount _{x I2} of insulators appear in Formula 8 below.
[0021]
(Equation 5)

[0022]
Moment M (moment component M _Z) deformation amount x _B2 and the insulator of the deformation amount x _I2 of the bush due around the kingpin axis k, the amount of deformation of the deformation amount x _B1 and the insulator of the bushing to be deformed directly by the lateral force F taking into account the x _I1, calculating the steering angle δ of the wheels, 9 formulas below are obtained.
[0023]
(Equation 6)

[0024]
Since the desired compliance steer characteristic is linear with respect to the lateral force F, as shown in FIG. 3, the steer angle of the wheel becomes the same at the boundary point between the low rigidity region and the high rigidity region. There is a need. Therefore, the elastic coefficient K _BL of the low rigidity area of the bush, the elastic coefficient K _BH of the high rigidity area, the elastic coefficient K _IL of the low rigidity area of the insulator, and the elastic coefficient K _IH of the high rigidity area of the bush are substituted into the above equation (9). The elastic coefficient of each elastic body may be determined so as to satisfy the following equation (10).
[0025]
(Equation 7)

[0026]
As described above, according to the support structure of the suspension device and the steering device of the present embodiment, of the suspension device, the link member disposed in the vehicle width direction or the substantially width direction, that is, the transverse link 2 is an elastic bush. 6, the steering gear box 5 of the steering device is supported on the vehicle body by an insulator 7 which is an elastic body, and the compliance steer of the wheels 1 suspended by the suspension device and connected to the steering device ( since the steering angle [delta]) is to maintain the linear characteristic with respect to lateral force F, the stiffness (modulus of elasticity K _I rigidity of the bush 6 (elastic coefficient K _B) and the insulator ₇₎ so as to set, regulations such as layout Thus, the compliance steer of the wheels can be set linearly without receiving the noise.
[0027]
The bush 6 and the insulator 7 each have a non-linear characteristic having a low rigidity region where rigidity against lateral force is small when lateral force is small, and a high rigidity region where rigidity against lateral force is large when lateral force is large. As a result, it is possible to reduce the reduction of noise and vibration such as road noise and shimmy in a straight traveling state or a substantially straight traveling state, improve camber rigidity in a turning state with a large lateral force, improve responsiveness, and improve steering stability. it can.
[0028]
The rigidity (elasticity coefficient K) of the bush 6 and the insulator 7 in the vehicle width direction is set such that the compliance steer (steer angle δ) in the low rigidity region becomes the same as the compliance steer (steer angle δ) in the high rigidity region. _{BL, K} BH, K _IL, because you to set the _K the _IH), compliance steering characteristics with respect to the lateral force from a low stiffness region of the bushing 6 and the insulator 7 to a high rigidity region, to a large state from a small state of words lateral force It can be linear continuously.
[0029]
Further, a deformation amount x _B1, x _I1 of the bush 6 and the insulator 7 is deformed directly by the lateral force F, the deformation amount x _B2 of the bush 6 and the insulator 7 to be deformed by the kingpin axis of the moment M generated by the lateral force F, based on the x _I2, the rigidity of the bushing 6 and the insulator 7 (modulus _{K BL, K BH, K IL} , K IH) for made to be set accurately set the rigidity of a desired bushing 6 and the insulator 7 can do.
[Brief description of the drawings]
1A and 1B show one embodiment of a support structure of a suspension device and a steering device of the present invention, wherein FIG. 1A is a plan view and FIG. 1B is a front view.
FIG. 2 is an explanatory diagram of a rigidity characteristic with respect to a lateral force required for a bush and an insulator of FIG. 1;
FIG. 3 is an explanatory diagram of a characteristic of a compliance steer with respect to a lateral force required for the wheel of FIG. 1;
[Explanation of symbols]
1 is a wheel 2 is a transverse link 3 is a tension rod 4 is a tie rod 5 is a steering gear box 6 is a bush 7 is an insulator

Claims (4)

The suspension device includes a link support elastic body that supports a link member disposed in a vehicle width direction or a substantially width direction to a vehicle body, and a steering support elastic body that supports a steering gear box to the vehicle body in a steering device. The rigidity of the link support elastic body and the steering support elastic body in the vehicle width direction is adjusted so that the compliance steer of the wheel suspended by the suspension system and connected to the steering system maintains a linear characteristic with respect to a lateral force. A support structure for a suspension device and a steering device, which is set. The link support elastic body and the steering support elastic body each have a non-linear rigidity characteristic in the vehicle width direction, and the rigidity characteristic includes a low rigidity region where rigidity against lateral force is small when lateral force is small. The supporting structure for a suspension device and a steering device according to claim 1, further comprising a high rigidity region in which rigidity with respect to the lateral force is large when the lateral force is large. Setting the rigidity of the link support elastic body and the steering support elastic body in the vehicle width direction such that the compliance steer of the wheel in the low rigidity area is the same as the compliance steer of the wheel in the high rigidity area. The support structure for a suspension device and a steering device according to claim 2. Based on the deformation amount of the link support elastic body and the steering support elastic body that is directly deformed by the lateral force, and the deformation amount of the link support elastic body and the steering support elastic body that is deformed by a moment about the kingpin axis generated by the lateral force. 4. The support structure for a suspension device and a steering device according to claim 1, wherein rigidities of the link support elastic member and the steering support elastic member are set.

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