JP3080254B2 - Vehicle suspension system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle suspension system for optimally controlling a damping coefficient of a shock absorber.

[0002]

2. Description of the Related Art Conventionally, as a vehicle suspension device for controlling a damping coefficient of a shock absorber, for example, Japanese Unexamined Patent Publication No.
What is described in 163011 is known.

This conventional vehicle suspension detects a sprung vertical speed and a relative speed between sprung and unsprung, and sets the damping coefficient to hard when both have the same sign, and sets the damping coefficient when both have different signs. Was used as software, and damping coefficient control based on the Skyhook theory was performed independently for four wheels.

[0004]

According to the above-mentioned skyhook theory, the damping force F can be expressed by an equation of F = α · V. Here, α is a control gain, and V is a signal relating to the sprung vertical speed. According to this theory, when the sprung vertical speed is 0, the damping force F = 0, and when the sprung vertical speed is high, a shock absorber having a damping characteristic of the damping force F = large is required.

However, an actual shock absorber has a certain damping coefficient even in a soft characteristic state, but has an upper limit on the maximum damping coefficient that can be generated. When the damping coefficient is set between the minimum damping coefficient and the maximum damping coefficient when the sprung vertical speed is larger than 0, the sprung mass is set to On road surfaces that fluctuate with speed, the damping coefficient is controlled to a higher damping coefficient than the minimum damping coefficient.In particular, the control power becomes excessive for high-frequency input, and the ride comfort deteriorates and the vehicle behavior becomes uncomfortable. There was a problem.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional problems, and has as its object to improve the riding comfort when the sprung vertical speed is low and to prevent the occurrence of uncomfortable vehicle behavior.

[0007]

Therefore, according to the present invention, when a control signal based on a sprung vertical speed is within a predetermined minute range, a deadlock control for fixing the shock absorber to a predetermined low damping characteristic is performed. The above object is achieved by providing a control unit.

That is, the vehicle suspension system of the present invention is shown in FIG.
Of, as shown in the claim corresponding diagram is interposed between the vehicle body side and the wheel side, the attenuation characteristic by attenuation characteristic changing means a, the extension side
Is a high damping characteristic and the HS characteristic is low pressure side.
SH characteristics with low damping characteristics on the side and high damping characteristics on the compression side,
A shock absorber b that can be changed to an SS characteristic in which both the expansion side and the compression side have low damping characteristics, and a sprung vertical speed detecting unit c that detects at least the sprung vertical speed of the vehicle;
Vehicle behavior detecting means d for detecting vehicle behavior ;
The control signal rises according to the control signal formed based on the speed.
A positive value formed from the sprung speed in the direction
The HS characteristic is defined as the control characteristic, and the control signal is determined from the downward sprung speed.
If it is a negative value to be formed, an attenuation characteristic control means e for setting the attenuation characteristic to the SH characteristic, and an attenuation characteristic control means e are provided.
Is, the control signal when in a predetermined small range, and the insensitive controller f for performing insensitive control for fixing the shock absorber b on SS characteristics, a structure in which a.

The dead control section f sets the range of the magnitude of the control signal for performing dead control to a damping force ratio or a damping coefficient of the low damping characteristic with respect to a maximum damping characteristic based on a predetermined stroke speed. It may be determined by the product of the ratio and a control signal for controlling to the maximum attenuation characteristic.

In order to achieve the above-mentioned object, the present invention provides
The invention described in 3 is interposed between the vehicle body side and the wheel side to reduce
Shock whose damping characteristics can be changed by damping characteristics changing means a
Check the absorber b and at least the sprung vertical speed of the vehicle.
A sprung vertical speed detecting means c for detecting vehicle behavior.
Vehicle behavior detecting means d that emits
Damping characteristic control means for controlling the damping characteristic of the absorber b
e) wherein said damping characteristic control is performed.
A control signal based on the sprung vertical speed is given to the means e by a predetermined value.
When it is within the minute range, the shock absorber b
An insensitive control unit f for performing insensitive control for fixing to low attenuation characteristics is provided.
In this case, the insensitive control unit f outputs a large control signal for performing insensitive control.
The maximum range is based on the specified stroke speed.
Damping force ratio or damping of said low damping characteristic to damping characteristic
Between the coefficient ratio and the control signal when controlling to the maximum attenuation characteristic.
It was determined by the product. Further, the insensitive control unit f may change the range of the magnitude of the control signal for performing the insensitive control according to the vehicle speed.

Further, the insensitive control section f may change a range of a control signal for performing insensitive control in accordance with a signal from the vehicle behavior detecting means d.

In addition, the insensitive control section f may control the range of the control signal for performing the insensitive control independently of the extension side characteristic and the compression side characteristic of the shock absorber b.

In addition, the dead zone control unit f may independently control the range of the control signal for performing dead zone control for the front wheel side and the rear wheel side of the shock absorber b.

[0014]

When the control signal based on the sprung vertical speed is larger than a predetermined value, the damping characteristic is controlled based on the vehicle behavior to obtain an appropriate control force.

When the control signal based on the sprung vertical speed is within a predetermined minute range, the insensitive control unit fixes the shock absorber to a predetermined low damping characteristic such as a minimum damping characteristic.

Therefore, it is difficult for the high-frequency input to be transmitted to the sprung portion, so that a good riding comfort can be obtained, and the behavior of the vehicle body is unlikely to be uncomfortable. In addition, the opportunity for driving the damping characteristic changing means is reduced, and the durability is improved.

[0017]

An embodiment of the present invention will be described with reference to the drawings. (First Embodiment) First, the configuration will be described.

FIG. 2 is a structural explanatory view showing a vehicle suspension system according to a first embodiment which is an embodiment of the invention according to claims 1, 4 to 7 , and is interposed between a vehicle body and four wheels. hand,
Four shock absorbers SA1, SA2, SA3, S
A4 (In explaining the shock absorber,
When these four are collectively referred to, and when explaining their common configuration, they are simply indicated as SA. ) Is provided. A vertical acceleration sensor (hereinafter, referred to as a vertical G sensor) 1 for detecting a vertical acceleration is provided on the vehicle body near each shock absorber SA. A load sensor 6 for detecting an upper-unsprung relative speed is attached, and a vehicle speed sensor 5 is provided on a power train (not shown). At a position near the driver's seat, there is provided a control unit 4 which receives signals from the sensors 1, 5, 6 and outputs a drive control signal to the pulse motor 3 of each shock absorber SA.

FIG. 3 is a system block diagram showing the above configuration. The control unit 4 includes an interface circuit 4a, a CPU 4b, and a drive circuit 4c. 6
Is input. In the interface circuit 4a, a set of five filter circuits shown in FIG. That is, L
The PF1 is a low-pass filter circuit for removing noise in a high frequency range (30 Hz or more) from signals sent from the upper and lower G sensors 1. LPF2 is a low-pass filter circuit for integrating a signal indicating acceleration that has passed through low-pass filter circuit LPF1 and converting the signal into a sprung vertical velocity. The BPF ₁ passes a bounce component signal v (v ₁ , v ₂ , v ₃ , v ₄
The numbers ₁ , ₂ , ₃ , and ₄ correspond to the positions of the respective shock absorbers SA. The same applies to the following. ) Is a band-pass filter circuit. The BPF ₂ is a bandpass filter circuit that forms a pitch component signal v ′ (v ₁ ′, v ₂ ′, v ₃ ′, v ₄ ′) by passing a frequency range including a pitch resonance frequency. The BPF 3 allows the roll component signal v ″ to pass through a frequency range including the roll resonance frequency.
(V ₁ ″, v ₂ ″, v ₃ ″, v ₄ ″). In this embodiment, the case where the sprung resonance, the pitch resonance, and the roll resonance have different frequencies is taken as an example. However, when these resonance frequencies are close to each other, only the BPF1 may be used as the bandpass filter.

Next, FIG. 4 is a sectional view showing the structure of the shock absorber SA.
A is a cylinder 30, a piston 31 that defines the cylinder 30 in an upper chamber A and a lower chamber B, an outer cylinder 33 in which a reservoir chamber 32 is formed on the outer periphery of the cylinder 30, a lower chamber B and a reservoir chamber 32. And a piston 32
A guide member 35 for guiding the sliding of the piston rod 7 connected to the outer cylinder 33, a suspension spring 36 interposed between the outer cylinder 33 and the vehicle body, and a bump rubber 37.

FIG. 5 is an enlarged sectional view showing a portion of the piston 31. As shown in FIG. 5, the piston 31 has through holes 31a and 31b formed therein, and An extension damping valve 12 and a compression damping valve 20 for opening and closing 31a and 31b, respectively, are provided. A communication hole 39 that connects the upper chamber A and the lower chamber B is formed at the tip of the piston rod 7 that penetrates the piston 31, and further changes the cross-sectional area of the communication hole 39. , And an expansion-side check valve 17 and a pressure-side check valve 22 that allow and shut off the flow of the fluid communication hole 39 in accordance with the flow direction of the fluid. The adjuster 40 is rotated by the pulse motor 3 (see FIG. 4).
Also, the first end of the piston rod 7 is
A port 21, a second port 13, a third port 18, a fourth port 14, and a fifth port 16 are formed. Reference numeral 38 in the figure denotes a retainer on which the pressure side check valve 22 is seated.

On the other hand, the adjuster 40 has a hollow portion 19, a first horizontal hole 24 and a second horizontal hole 25 communicating between the inside and the outside, and a vertical groove 23 formed in the outer peripheral portion. I have.

Therefore, between the upper chamber A and the lower chamber B, as a flow path through which fluid can flow during the extension stroke, the inside of the extension-side damping valve 12 is opened through the through hole 31b to open the lower chamber. B, the first port D on the extension side, the second port 13 and the flute 2
(3) a second expansion passage (E) that opens the outer peripheral side of the expansion damping valve (12) through the fourth port (14) to reach the lower chamber (B);
The extension side check valve 17 is opened via the port 13, the vertical groove 23, and the fifth port 16, and the extension side third valve reaching the lower chamber B is opened.
The flow path F, the third port 18, the second lateral hole 25, and the hollow portion 19
There are four flow paths of a bypass flow path G which leads to the lower chamber B via. Also, as a flow path through which fluid can flow in the pressure stroke,
The upper side chamber A is opened by opening the pressure side first flow path H passing through the through hole 31a and opening the pressure side damping valve 20, and opening the pressure side check valve 22 via the hollow portion 19, the first horizontal hole 24, and the first port 21. Pressure side second flow path J leading to the hollow portion 19, the second lateral hole 2
5, there are three flow paths: a bypass flow path G which reaches the upper chamber A via the third port 18.

That is, the shock absorber SA is configured such that the damping coefficient can be changed in multiple stages with characteristics as shown in FIG. 6 on both the extension side and the compression side by rotating the adjuster 40. That is, as shown in FIG. 7, a state where both the extension side and the compression side are soft (hereinafter, the soft area S
When the adjuster 40 is rotated counterclockwise from S), the damping coefficient can be changed in multiple stages only on the extension side, and the compression side becomes an area fixed to a low attenuation coefficient (hereinafter referred to as an extension side hard area HS). Conversely, when the adjuster 40 is rotated clockwise, the damping coefficient can be changed in multiple stages only on the compression side, and the expansion side becomes a region fixed to a low attenuation coefficient (hereinafter referred to as a compression side hard region SH). I have.

7, the KK section, the MM section, and the NN section in FIG. 5 when the adjuster 40 is disposed at the position of, are respectively shown in FIGS. FIG. 10 shows the damping force characteristics of each position in FIGS.

Next, the operation of the control unit 4 for controlling the driving of the pulse motor 3 will be described with reference to the flowchart of FIG. This control is performed separately for each shock absorber SA.

Step 101 is a step of reading the vertical acceleration gg obtained from the vertical G sensor 1 and the vehicle speed VV obtained from the vehicle speed sensor 5.

Step 102 is a step for setting a bounce coefficient α, a pitch coefficient β, and a roll coefficient γ based on a map corresponding to a vehicle speed not shown. In addition,
The signs of _f and _r attached to the lower right of each coefficient α, β, γ are
One for the front wheel and one for the rear wheel are shown.

In step 103, the vertical acceleration gg is filtered by filter circuits LPF1, LPF2, BPF1, BPF.
2, a process for obtaining a bounce component signal v, a pitch component signal v ′, and a roll component signal v ″ by processing with the BPF 3.

Step 104 uses the following equation (1).
This is a step of calculating control signals V (V ₁ , V ₂ , V ₃ , V ₄ ) for the position of each wheel based on the component signals v, v ′, v ″.

[0031]

(Equation 1) Note that α _f , β _f , and γ _f are front wheel coefficients α _r , β _r , and γ _r are rear wheel coefficients v ₁ , v ₁ ′, and v ₁ ″: front-wheel right sprung vertical velocity. Signals v ₂ , v ₂ ′, v ₂ ″: front wheel left sprung vertical speed signal v ₃ , v ₃ ′, v ₃ ″: rear wheel right sprung vertical speed signal v ₄ , v ₄ ′, v ₄ ": A sprung vertical speed signal on the left rear wheel. In each of the equations, the part bounded by the first α _f and α _r is the bounce rate, the part bounded by β _f and β _r is the pitch rate, and the part bounded by γ _f and γ _r Is the roll rate. As described above, the bounce rate (spring vertical speed), the pitch rate, and the roll rate are obtained from the signals from the upper and lower G sensors 1, and the portion for obtaining these in the upper and lower G sensors 1 and the control unit 4 is a request. , A sprung vertical speed detecting means, a pitch rate detecting means, and a roll rate detecting means.

Step 105 is a step for setting the proportional range θT, θC on the extension side / pressure side and the dead zone range θNT, θNC on the extension side / pressure side. That is, as shown in FIG. 16, the proportional ranges θT and θC are the shock absorbers SA.
Is determined in proportion to the control signal V within the range from the maximum damping coefficient CMAX to the minimum damping coefficient Cmin. The dead zone ranges θNT and θNC are the damping coefficients (step numbers) of the shock absorber SA. ) Is fixed to the number of steps at which the minimum attenuation coefficient is obtained. And
Each range θT, θC, θNT, θNC is variable,
This is set in step 105 . Next, each range θT, θC, θNT, θNC in this step 105
The following describes how to determine. That is, the control signal value VT of the upper limit of the extension side proportional range θT and the control signal value VC of the lower limit of the pressure side proportional range θC are variable according to the vehicle speed VV, and are determined by the map shown in FIG. I do. The characteristics of this map are different between those for the front wheels and those for the rear wheels, and can have characteristics such as understeer characteristics.

The control signal values V _TM and V _CM for determining the upper and lower limits of the respective dead zone ranges θ _NT and θ _NC are obtained by the following equations. V _TM = (C _Tmin / C _TMAX ) × V _T ... V _CM = (C _Cmin / C _CMAX ) × V _{C. In} addition, C _Tmin / C _TMAX and C _Cmin / C _CMAX are based on a predetermined piston speed. This is the ratio between the maximum damping coefficient and the minimum damping coefficient, which are variable according to the vehicle speed VV, and are set based on the map shown in FIG.

Step 106 is a step of controlling the damping coefficient (actually, the number of driving steps of the pulse motor 3) based on the control signal V and the respective ranges θ _T , θ _C , θ _NT , and θ _NC . In this case, the attenuation coefficient (the number of steps) is set by the following equation (2).

[0035]

(Equation 2) MaxSTEP is the number of steps at which the attenuation coefficient becomes maximum.

Therefore, in the vehicle suspension system of the embodiment, as shown in the time chart of FIG. 16, when the control signal V changes, the control signal V is changed to the dead zone ranges θ _NT and θ _NC.
During this period, the shock absorber SA is fixedly controlled in the soft region SS, and when the control signal V falls within the proportional ranges θ _T , θ _C , the expansion side hard region HS and the compression side hard region SH become the vertical acceleration gg. Is controlled so as to have a high attenuation coefficient proportional to the control signal V.

In the first embodiment described above, the following effects can be obtained.

Since a sufficient control force can be generated not only for the bounce but also for the roll and the pitch, it is possible to provide a vehicle suspension system having excellent ride comfort and steering stability.

In obtaining the bounce rate, pitch rate, and roll rate, different coefficients α,
Since β and γ are used, in the vehicle, even if the sprung resonance frequency, the pitch resonance frequency, and the roll resonance frequency are different from each other, each rate can be accurately detected based on the sprung vertical speed.

When traveling on a good road with a small amount of sprung movement, even if there is a high frequency input, the control is fixed to the soft characteristic SS, so that the control force does not become excessive and a good ride comfort is obtained. At the same time, the vehicle does not behave unnaturally. In addition, the frequency of switching the pulse motor 3 is reduced, and the durability of the pulse motor 3 is improved.

The dead zone ranges θ _NT , θ _NC and the proportional ranges θ _T , θ _C can be appropriately set in accordance with the damping coefficient ratio and the vehicle speed VV which are set in advance in an optimal manner. The damping coefficient or damping force can be set to an optimal state.

Since the ranges θ _T , θ _C , θ _NT , and θ _NC are independently controlled on the extension side and the compression side, and are independent on the front and rear sides, the degree of freedom in tuning is high.

Next, other embodiments will be described. In describing these embodiments, only differences from the first embodiment will be described. In addition, the first reference
The same reference numerals as those in the embodiments indicate the same objects.

(Second Embodiment) In the second embodiment, a part of the control unit 4 is different from that of the first embodiment. That is, in the second embodiment, the following equation is used for obtaining the control signal V. 2 is used.

[0045]

(Equation 3) In the second embodiment, the part for obtaining the bounce component v is different, and the bounce component v is different from each shock absorber S.
Only the component at the position A is input. Therefore, this second
In the embodiment, compared to the first embodiment, the control is such that the bounce component of each wheel is emphasized, and the characteristics of suppressing the roll and the pitch are suppressed.

(Third Embodiment) In a third embodiment, when the pulse motor 3 is driven as a shock absorber SA of a variable damping coefficient type, as shown in FIG. Have a well-known structure that changes from high attenuation to low attenuation (for example, Japanese Utility Model Application Laid-Open No. 63-112914).
No. public relations).

Although the embodiment has been described above, the specific configuration is not limited to this embodiment, and any change in design or the like without departing from the gist of the present invention is included in the present invention.

For example, in the embodiment, the pitch rate is determined from the difference between the front and rear sprung vertical speeds, and the roll rate is determined from the difference between the left and right sprung vertical speeds. A sensor that detects a change in pitch angle or a sensor that detects a change in roll angle may be used.

In the embodiment, the dead zone ranges θ _NT , θ _NC
To set the damping coefficient ratio C _Tmin / C _TMAX , C _Cmin / C
_{Although the CMAX} is used, a damping force ratio may be used instead of the damping coefficient, and the damping coefficient ratio is made variable according to the vehicle speed VV. May be set based on the sprung vertical acceleration gg, which is a signal that can determine the condition of the road surface, the relative speed obtained from the load sensor 6, or the unsprung vertical acceleration obtained by a non-sprung acceleration sensor (not shown).

In the embodiment, the dead zone ranges θ _NT , θ _NC
In the above, the minimum damping coefficient is fixed, but a predetermined low damping coefficient or a low damping characteristic with a low damping force larger than the lowest damping coefficient may be used.

[0051]

As described above, according to the vehicle suspension system of the present invention, when the control signal based on the sprung vertical speed is within a predetermined minute range, the shock absorber is controlled to a predetermined low level by the damping characteristic control means. A dead-end control unit that performs dead-end control that fixes the damping characteristic is provided. When traveling on a good road with a small amount of sprung motion, it is fixed at a low-damping characteristic even if there is a high-frequency input. Is not excessive, good ride comfort is obtained, and unnatural behavior does not occur in the vehicle. In addition, the operation frequency of the damping characteristic changing means is reduced, and the durability is improved. The effect is obtained. According to the first aspect of the present invention,
The damping characteristics of the shock absorber are set to HS according to the vertical speed.
Switching to the characteristics, SH characteristics and SS characteristics
The above effects can be obtained in a device that can suppress
Can be In the invention according to claim 2, the insensitive control unit
In, the range of the magnitude of the control signal for performing the insensitive control,
For maximum damping characteristics based on a predetermined stroke speed
Low damping force ratio or damping coefficient ratio and maximum damping
Determined by the product of the control signal and the characteristic
The optimal setting of the dead zone and the range of proportional control.
The effect that it can be set is obtained. Also, billing
In the invention described in Item 3, the damping characteristic control means includes
The control signal based on the vertical movement speed within the specified minute range
At some point, the shock absorber is fixed to the specified low damping characteristics.
A blind control unit is provided to perform blind control.
Range of the magnitude of the control signal that performs insensitive control in the unit
To the maximum damping characteristic based on the predetermined stroke speed.
Low damping force ratio or damping coefficient ratio
Determined by the product of the control signal when controlling to the damping characteristic
So that all damping force variable characteristics
The dead band and proportional control range
The effect of being able to set appropriately is obtained. Further
In addition, the dead zone control section sets the range in which
(Claim 4) or insensitive control
Change the range to perform according to road surface conditions and vehicle behavior
(Claim 5), and the range in which
Independent expansion and compression characteristics of the absorber
It is possible to change any damping force
Dead zone and proportional control for characteristic shock absorbers
Range can be set optimally.
It is.

[0052]

According to the seventh aspect of the present invention, the insensitive control unit controls the range of the control signal for performing the insensitive control independently for the front wheel side and the rear wheel side of the shock absorber. , Understeer characteristics, etc., and the degree of freedom in tuning is further improved.

[Brief description of the drawings]

FIG. 1 is a conceptual view of a claim showing a vehicle suspension system of the present invention.

FIG. 2 is a configuration explanatory view showing a vehicle suspension system according to a first embodiment of the present invention.

FIG. 3 is a system block diagram showing a vehicle suspension system according to a first embodiment.

FIG. 4 is a sectional view showing a shock absorber applied to the first embodiment device.

FIG. 5 is an enlarged sectional view showing a main part of the shock absorber.

FIG. 6 is a damping force characteristic diagram corresponding to a piston speed of the shock absorber.

FIG. 7 is a damping coefficient characteristic diagram corresponding to a step position of a pulse motor of the shock absorber.

FIG. 8 is a perspective view of the shock absorber shown in FIG.
It is -K sectional drawing.

FIG. 9 is a perspective view of the shock absorber shown in FIG.
It is a -M sectional view.

FIG. 10 is a sectional view taken along line NN of FIG. 5 showing a main part of the shock absorber.

FIG. 11 is a damping force characteristic diagram when the shock absorber is on the extension side hard.

FIG. 12 is a damping force characteristic diagram of the shock absorber in a soft state on an extension side and a compression side.

FIG. 13 is a damping force characteristic diagram of the shock absorber in a pressure-side hard state.

FIG. 14 is a block diagram showing a main part of the control unit of the first embodiment.

FIG. 15 is a flowchart showing a control operation of the control unit of the first embodiment.

FIG. 16 is a time chart showing the operation of the first embodiment.

17 is a map showing the lower limit of the upper control signal value V _T and the pressure side of the proportional range theta _C of the extension side of the proportional range theta _T of the first embodiment apparatus.

FIG. 18 is a damping coefficient characteristic diagram of the shock absorber of the device of the third embodiment.

[Explanation of symbols]

 a damping coefficient changing means b shock absorber c sprung vertical speed detecting means d vehicle behavior detecting means e damping characteristic control means f insensitive control section

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Tetsu Takahashi 1370 Onna, Atsugi-shi, Kanagawa Prefecture Inside Atsugi Unisia Corporation (72) Inventor Makoto Kimura 1370 Onna, Atsugi-shi, Kanagawa Prefecture Inside Atsugi Unisia Corporation (56) References JP-A-5-169949 (JP, A) JP-A-2-3512 (JP, A) JP-A-2-303913 (JP, A) JP-A-61-184113 (JP, A) JP-A-3 JP-A-208717 (JP, A) JP-A-3-217312 (JP, A) JP-A-4-321415 (JP, A) JP-A-4-163220 (JP, A) JP-A-62-10008 (JP, U) ) Hikaru 1-161102 (JP, U) (58) Field surveyed (Int. Cl. ⁷ , DB name) B60G 17/015

Claims (7)

(57) [Claims] 1. A damping characteristic changing means interposed between a vehicle body side and a wheel side, and a damping characteristic changing means is provided , and the extension side is a high damping characteristic and a compression side.
HS characteristics with low damping characteristics, and compression characteristics with low damping characteristics on the extension side.
SH characteristics with high attenuation characteristics on the compression side and low on both the extension side and compression side
A shock absorber that can be changed to an SS characteristic as a damping characteristic , a vehicle behavior detecting means that has at least a sprung vertical velocity detecting means for detecting a sprung vertical velocity of the vehicle, and detects a vehicle behavior, and a sprung vertical velocity Control according to the control signal formed based on the
The control signal is a positive value formed from the upward sprung speed.
If the damping characteristic is set to the HS characteristic, the control signal
If it is a negative value formed from the upper speed, the damping characteristic
A damping characteristic control means for the gender, provided in the damping characteristic control means, when said control signal is within a predetermined small range, the shock absorber SS JP
Vehicle suspension system, characterized by comprising a dead controller that performs insensitive control for fixing the gender, the. 2. A damping force ratio or a damping coefficient ratio of the low damping characteristic with respect to a maximum damping characteristic based on a predetermined stroke speed, wherein a range of a magnitude of a control signal for performing a deadlock control is set by the deadening control unit. 2. The vehicle suspension device according to claim 1, wherein the vehicle suspension device is determined by a product of the control signal and a control signal for controlling the maximum damping characteristic. (3)Interposed between the vehicle body and the wheel side,
Shock absorber whose damping characteristics can be changed by means of changing the characteristics
And At least the sprung vertical speed which detects the sprung vertical speed of the vehicle
Vehicle behavior detection that has speed detection means and detects vehicle behavior
Means ,Control damping characteristics of shock absorber based on vehicle behavior
Vehicle suspension equipped with a damping characteristic control means
hand, The damping characteristic control means includes a control based on a sprung vertical speed.
When the control signal is within the predetermined minute range,
Insensitive control for fixing the sensor to a predetermined low attenuation characteristic
Provide a control unit, The blind control unit controls the magnitude of a control signal for performing blind control.
The range is defined as the maximum damping characteristic based on the specified stroke speed.
Damping force ratio or reduction of the low damping characteristic to Decay coefficient ratio
And the product of the control signal when controlling to the maximum attenuation characteristic
It is characterized by being decided more Vehicle suspension
Place. 4. A control in which the insensitive control section performs insensitive control.
Signal range is changed according to vehicle speed
4. The vehicle suspension device according to claim 1, wherein: 5. A control in which the insensitive control section performs insensitive control.
The range of the signal is changed according to the signal from the vehicle behavior detection means.
4. The vehicle suspension according to claim 1 , wherein the vehicle suspension is further modified . 6. A control in which the dead control section performs dead control.
The range of the signal depends on the extension characteristics of the shock absorber and the compression characteristics.
2. The method according to claim 1, wherein
6. The vehicle suspension according to claim 5 . 7. A control in which the insensitive control section performs insensitive control.
Set the signal range between the one on the front wheel side of the shock absorber and the rear
It is characterized in that it is done independently with the wheel side
The vehicle suspension according to claim 1 .