JPH03231015A - Alignment control device for wheel - Google Patents

Abstract

PURPOSE:To improve running performance by correcting target alignment by an amount equivalent to a change in alignment determined from the stroke position of a wheel, in a device which automatically controls alignment of the camber angle of wheel according to a running state. CONSTITUTION:Actuators 2, 4, 6, and 8 to regulate the camber angle of each of front and rear wheels being alignment are provided. Electromagnetic type control valves 10, 12, 14, and 16 are located in a feed passage 18 connected to the delivery side of a pump 20, so that the actuators 2-8 are controlled, respectively. The control valves 10-16 are controlled by a controller 32 according to the running state of a vehicle. In control thereof, based on the detecting value of the stroke position of a wheel, a change in a chamber angle is determined from a relation between the stroke position of a vehicle and a change in a camber angle. Correction is made on the target camber angle of a wheel, set according to the running state detecting result of a vehicle, by an amount equivalent to the change in a camber angle, and the control valves 10-16 are controlled according to a target camber angle after correction.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a wheel alignment control device suitable for automatically controlling the alignment of wheels, such as camber angles, in accordance with driving conditions in automobiles. .

[Prior Art] Conventionally, devices have been proposed that automatically control the alignment of vehicles such as automobiles according to driving conditions, and for example, a device shown in Japanese Patent Application Laid-Open No. 193781/1983 is known. .

[Problems to be Solved by the Invention] However, the alignment of wheels of automobiles etc. changes depending on the stroke position of the wheel.

Even if alignment is controlled, desired alignment may not be obtained in some cases.

The present invention has been made in view of the above-mentioned problems.

It is an object of the present invention to provide a wheel alignment control device that can obtain desired alignment even if the stroke position of the wheel changes.

[Means for Solving the Problems] For this reason, the wheel alignment control device of the present invention is provided in one or both of the front wheels and the rear wheels to adjust the alignment of the vehicle. an actuator for detecting a vehicle, a driving state detecting means for detecting a traveling state of the vehicle, a stroke detecting means for detecting a stroke position of a wheel, a storage means for storing a relationship between a stroke position of a wheel and an alignment change; a target alignment setting section for setting a target alignment of the wheels according to the running state of the vehicle detected by the running state detecting means; an alignment change calculation section that calculates an alignment change from the stroke position of the wheel and the relationship between the stroke position of the wheel and the alignment change stored in the storage means; The present invention is characterized by comprising a target alignment correction section that performs correction by the alignment change determined by the change calculation section, and an actuator control section that controls the actuator so that each wheel takes the corrected target alignment. .

Note that, for example, a camber angle can be used as the above alignment.

[Function] According to the wheel alignment control device of the present invention described above,
The running state detection means detects the running state of the vehicle, and the stroke detection means detects the stroke position of the wheel. Then, the target alignment setting section of the control means sets the target alignment of the wheels according to the running state of the vehicle detected by the running state detection means, and the alignment change calculation section sets the wheel stroke detected by the stroke detection means. By referring to the relationship between the stroke position of the wheel and the alignment change stored in the storage means, the wheel alignment change is determined, and the target alignment correcting unit calculates the target alignment change by referring to the relationship between the wheel stroke position and the alignment change stored in the storage means. The alignment is corrected by the alignment change calculated by the alignment change calculation section, and the actuator is controlled by the actuator control section so that each wheel has the corrected target alignment.

[Embodiment] A wheel alignment control device will be described below as an embodiment of the present invention with reference to the drawings. Fig. 1 is a schematic diagram showing the overall configuration, and Fig. 2 shows an example of how the actuator is installed. 3 is a flowchart explaining the operation, FIG. 4 is a diagram showing a vehicle speed-camber angle map (map I) stored in the ROM of the controller, and FIG. 5 is a diagram showing the map I. A diagram showing the vehicle speed-camber angle map (map ■) stored in the ROM of the controller, Figure 6 is a diagram showing the relationship between changes in wheel stroke and camber angle, and Figure 7 is a diagram showing the relationship between vehicle body roll and camber angle. FIG. Note that this embodiment controls the camber angle, which is one of the alignments,
Hereinafter, in the description of the embodiments, the alignment control device will also be referred to as a camber angle control device.

In Fig. 1, reference numeral 2 is an actuator that adjusts the camber angle of the left front wheel, 4 is an actuator that adjusts the camber angle of the right @ wheel, 6 is an actuator that adjusts the camber angle of the left rear wheel, and 8 is an actuator that adjusts the camber angle of the right rear wheel. This is an actuator that adjusts the camber angle.

These actuators 2 to 8 are constituted by hydraulic cylinders, and specific pressures are provided to the suspension as shown in FIG. 2, for example. In other words, Figure 2
This is a front view of the 111J, and an actuator A is interposed between the upper end of the strut S of the strut type suspension and the vehicle body F, and by expanding or contracting the actuator A, the upper end position of the strut S is adjusted in the vehicle width direction. This makes it possible to adjust each camber of each vehicle @W.

Each actuator 2, 4, 6 and 8 is an electromagnetic control valve 10. ] 2, 14 and 16. Each control valve 10 , 12 , 14 and 16 is connected to a pump 20 via a supply line 18 and to an oil reservoir 24 via a discharge line 22 . The pump 2o is driven by an engine (not shown), etc., and pumps into an oil reservoir 24.
The oil inside is sucked and discharged to the supply path 18.

Further, an accumulator 26 is connected to the supply path 18, and a reservoir 24 is also connected via a relief valve 28, so that the supply path 18 is maintained at a set pressure.

Each of the control valves 10, 12, 14, and 16 is set to a first position in which supply and discharge of oil to each actuator 2 to 8 is prohibited and locked, and a first position in which each actuator 2 to 8 is locked by each control signal from the drive circuit 30. A second position where oil is supplied and discharged in the direction of extension (positive camber direction) and a third position where oil is supplied and discharged in the direction in which each actuator 2 to 8 contracts (negative camber direction) can be taken individually. .

Reference numeral 32 denotes a controller serving as a control means for outputting control signals to the drive circuit 30. This controller 32 performs predetermined program processing based on signals input from each sensor, which will be described later, and outputs control signals to the drive circuit 30. This is what is output. In particular, this controller 32 includes a target camber angle setting section (not shown) that sets a target camber angle of each wheel, a camber angle change calculation section (not shown) that calculates a camber angle change depending on the stroke position of the wheel, A target camber angle correction section (not shown) that corrects the target camber angle by the amount of change in camber angle, and a camber angle control section (not shown) that controls the actuator based on the target camber angle are provided.

Therefore, in the controller 32, the above-mentioned predetermined program and maps I, II (
ROM (storage means) 34.
Furthermore, although not shown in the drawings, an input circuit for inputting output signals from each sensor, a CPU, a RAM, and an output circuit for executing calculations and processing according to a program, and an interface between these elements are provided.

The above-mentioned sensors include a well-known vehicle height sensor 36 that detects the vehicle height of each wheel W, that is, the vehicle height of each part of the left front wheel, right front wheel, left rear wheel, and right rear wheel, and a steering wheel (not shown). steering angle.

A steering sensor (driving state detecting means) 38 for detecting the vehicle speed, a vehicle speed sensor (driving state detecting means) 40 for detecting the vehicle speed, a displacement sensor 42 for detecting the stroke position of the actuator 2 for the left front wheel, and a displacement sensor 42 for detecting the stroke position of the actuator 4 for the right front wheel. A displacement sensor 44 that detects the stroke position, a displacement sensor 46 that detects the stroke position of the left rear wheel actuator 6, and a displacement sensor 48 that detects the stroke position of the right rear wheel actuator 8 are provided.

Next, the processing executed by the controller 32 will be explained according to the flowchart shown in FIG.

The controller 32 executes program processing according to the flowchart shown in FIG. 3 when an engine switch (ignition switch), not shown, is turned on.

First, in step S1, initialization is performed, that is, a predetermined memory area necessary for program processing is cleared to zero or set to an initial value.

Next, in step S2, the outputs of the sensors 36 to 48 are read and stored in a predetermined memory area.

Subsequently, the process advances to step S3, and the vehicle speed V stored in step S2 is the set vehicle speed V. Determine whether it is the above. This set vehicle speed ■. Here, a vehicle speed of about 10 to 20 km/h is set, but other low speed values may be set.

If rYESJ is determined in step S3, the process proceeds to step S48, where the magnitude of the steering angle δ is increased, that is, Iδ1) is the preset steering angle δ. No Js size is judged more than that.

When the vehicle is in a turning state, 1δ1 becomes δ. Therefore, the process proceeds to step S5, and the target value (target camber angle) θ of the camber angle of the wheel W is determined from the map ■.

seek.

However, since the target camber angle obtained in step S5 is corrected in the subsequent step S9, the reference target camber angle θ
Call it 1.

In addition, in the following explanations, items that apply to the front wheel are marked with F, items that apply to the rear wheel are marked with R, and items that apply to the inside wheel of the turn are marked with ``work'', and items that apply to the outside wheel of the turn are referred to as ``work''. are distinguished by adding O. For example, the target camber angle of the inner turning axis of the front wheel is θtF1. The target camber angle of the front wheel on the outside of the turn is θtFo, and the target camber angle of the rear wheel on the inside of the turn is 0t.
RI, the target camber angle of the rear wheel on the outside of the turn is expressed as θtRo.

Map I has a front wheel as shown in FIG. 4(a), and a rear wheel as shown in FIG. 4(b).

In other words, for the front wheels, at low speed (vehicle speed V is the set vehicle speed ■
. (When the vehicle speed is below the set vehicle speed V1), the standard target camber angle θIFI of the wheel on the inside of the turn is set to a constant value on the positive side, and the standard target camber angle θ, Fo of the wheel on the outside of the turn is set to a constant value on the negative side. At low and medium speeds (when the vehicle speed is higher than the set vehicle speed 71 and lower than the set vehicle speed v2), the reference target camber angle θxFI of the wheel on the inside of the turn decreases from the positive side to the neutral side as the speed increases, and the turning speed increases. The reference target camber angle θ□FO of the outside wheel is set to increase from the negative side to the neutral side as the speed increases, and at medium to high speeds (when the vehicle speed Reference target camber angle θ□F
Both the reference target camber angle θLFO of the wheel on the outside of the turn are set to neutral (that is, ±0).

The rear wheels are arranged as shown in Fig. 4(b), and at low speeds (vehicle speed V is the set vehicle speed ■).

When the vehicle speed is below the set vehicle speed V0), the standard target camber angle θ1RI of the wheel on the inside of the turn is set to a constant value on the negative side, and the standard target camber angle θ1RO of the wheel on the outside of the turn is set to a constant value on the positive side. At medium speeds (when the vehicle speed V is above the set vehicle speed V□ and below the set vehicle speed V), the standard target camber angle θzRI of the wheel on the inside of the turn increases from the negative side to the positive side as the speed increases, and The standard target camber angle θxRo of the wheels is set to decrease from the positive side to the negative side as the speed increases, and at high speeds (when the vehicle speed V is equal to or higher than the set vehicle speed 71),
The standard target camber angle θ, R-work for the wheel on the inside of the turn is set to a constant value on the positive side, and the standard target camber angle θiRo of the wheel on the outside of the turn is set to a constant value on the negative side.

In this way, in step S5, the reference target camber angle θxFIy θIFO2θtRI+ θIRO of each wheel is determined.
is determined, in the following step S9. A first correction is applied to each of the determined reference target camber angles θIFI to θtRo.

This first correction includes a correction that takes into account changes in camber angle due to changes in wheel suspension stroke (stroke change correction), a correction that takes into account changes in camber angle due to vehicle body roll (camber angle correction during roll), and A correction (load correction) that takes into account the change in canvas thrust force due to the loaded load, and a correction that takes into account the change in camber angle caused by steering (steering correction) is performed.

In general, when the suspension stroke of the wheel W changes due to bumps, rebounds, acceleration/deceleration conditions, vehicle speed, etc., the camber angle 0 of the wheel W changes accordingly, so correction at the time of stroke change is applied to such a suspension stroke. This is to compensate for the corresponding change in the camber angle.1 For example, the stroke and key angle shown by the solid line in Fig. 6 are corrected. Controller 3 shows the relationship (map) with the member angle.
2, and correct the standard camber angle 01 of each wheel by the amount of camber angle (stroke corresponding camber angle) 02 that changes according to the stroke change △L of each car @W. do.

The camber angle correction during roll is performed because the camber angle of each wheel changes depending on the vehicle's front and rear conditions.

This corrects the change in the camber angle due to the roll of the vehicle body, and the roll angle φ is adjusted based on the detected value of the vehicle height sensor 36.
For example, calculate the relationship (map) between 711-le and camber angle as shown in FIG.
The standard target camber angle θ of each wheel W is corrected by the camber M (, r! - camber angle) θ according to the change in the roll angle φ of 7, Δφj5. The stroke 7 and the call angle φ can be calculated by a known calculation method based on the detection information of the vehicle height sensor 36 of each wheel W described above. These values are calculated from the 36 detected values, φ is calculated, and each correction amount θ2. θ,
seek.

Further, each of the maps shown in FIGS. 6 and 7 described above is an example, and each map has different characteristics depending on the configuration of each part of the vehicle. Further, the size of the vertical axis (camber angle) of the map in FIG. 7 does not necessarily correspond to map I, and often takes a relatively smaller value than the value of the camber angle represented by map ■.

Load correction is to correct the change in the camber angle corresponding to the change in the canvas thrust force caused by the loading state of the vehicle.2For example, the load (or total weight of the vehicle body) We that is applied to the vehicle and the camber angle corresponding to this. The relationship with the correction coefficient etc. is stored in the controller 32 as a map, and the load We is calculated based on the load inspection information from the load sensor set for each wheel. The camber angle correction coefficient etc. are determined from the above.

However, when considering canvas thrust force, it is better to consider the tire's eigenvalue.

The correction during steering is to M7H the amount by which the camber angle changes due to steering itself.The relationship between the steering angle and the change in the camber angle is stored in the controller 32 as a map, and this map and the steering The correction amount of the camber angle is determined from the steering angle information detected by the angle sensor 38.

On the other hand, the vehicle is almost Ii! While moving forward, 151 becomes δ
1. Since it is smaller than , the process advances to step S6.

In the camber angle setting section, the target amount of the camber angle of the wheel W (target camber angle) θt is determined from the map ■, and the reference target camber angle θ is first determined. This map ■, which seeks
As shown in the figure, the target camber angle θ of the front wheels. F is positively the target camber angle θ of the rear wheel. R is set on the negative side, but both are close to neutral at low speeds.

As the vehicle speed increases, the tendency toward the positive side or the negative side is strengthened, and when the vehicle speed exceeds the set vehicle speed V, it is set to take a constant value on the positive side or negative side, respectively. In this case, the target camber angles are set to be the same on the left and right axes.

When the reference target camber angle θxF+θ1R of each wheel is determined in step S6 in this way, in the subsequent step S8, each of the determined reference target camber angles θ, Fy
A second correction is applied to θ and R.

In this second correction, the stroke change correction, the roll camber angle, and the correction load correction described in the first correction are performed.

On the other hand, the vehicle speed V is smaller than the set vehicle speed v0.

If "NO" is determined in step S3, the process proceeds to step S7, where a preset reference value θ is determined. F, θ. R is the target camber angle (target value) of the camber angle of the wheel W θtF+ θt
Set as R. In this way, the reason why the camber angle θ is fixed to a constant reference value is that in such a low speed region, controlling the camber angle θ has little practical effect, and rather reduces the control frequency and simplifies the control. This is because it is more advantageous to do so.

Note that the reference value θ. F+e. Both R are often set to a neutral state (that is, ±O), but one or both may be set to a slightly positive side or a slightly negative side. For example, the above map H
As in, vehicle speed ■. When the camber angle of the front wheels is set to the positive side and the camber angle of the rear wheels is set to the negative side, the reference value θ of the front wheels is set so as to be almost continuous with the v'=voO value in map n. With F on the positive side, the reference value θ for the rear wheel. It is conceivable to set R to the negative side.

In this way, each step S9. S8. When the target camber angle θ is set in S7, the process proceeds to step S1°, where the camber angle control unit outputs a control signal to the moving parts of each actuator 2, 4, 6.8 through the controller 32.
Each actuator 2°4', 6.8 is operated to actively move the upper end position of the strut S in the vehicle width direction so that the camber angle θ of each wheel W becomes the target value θ.

After completing the process in step S10 in this manner, the process returns to step S2 and the processes from step S2 onwards are repeated. Therefore, while the vehicle is running, camber control of each wheel W by each actuator 2 to 8 is continuously performed at a predetermined cycle based on the vehicle speed, suspension stroke, and roll state of the vehicle body. Note that the repetition of the processing from step S2 onwards is performed with one cycle being approximately several ms, although it depends on the capabilities of the CPU, etc. in the controller 32.

According to the wheel alignment control device (wheel camber angle control device) of this embodiment configured as described above, when driving at low speed, the reference value θ is close to a preset neutral state. F, θ. Since the camber angle is set at R, the canvas thrust forces related to the turning grip forces of the front wheels and the rear wheels are approximately close to each other, and the steering characteristics are set to a state close to neutral.

This ensures sufficient straight-line stability and steering performance including turning performance when driving at low speeds.

Furthermore, during this low-speed running (when V<V.), the camber angle is fixed to the reference value and no special camber angle adjustment is performed, so that the frequency of control in this region can be reduced.

Then, when the vehicle speed (■) increases and becomes equal to or higher than the set vehicle speed v, the camber angle θ is controlled according to the vehicle speed (■) and the steering angle δ.

In other words, the steering angle δ is the predetermined value δ. When driving straight or almost straight, the camber angle OR on the rear wheel side changes as the vehicle speed increases until the vehicle speed V reaches the set vehicle speed 78 or higher and reaches the set vehicle speed v4. Camber angle θF
It is controlled to be on the negative side.

Therefore, as the vehicle speed increases, the turning grip force of the rear wheels increases compared to the turning grip force of the front wheels, and the steering characteristics of the vehicle tend to understeer.

This improves the straight-line stability of the vehicle, which is required as the vehicle speed increases, and enables stable high-speed travel.

Furthermore, when the vehicle speed V increases to a set vehicle speed of 71 or more, the camber angle OR of the rear wheels is set to be more negative than the camber angle θF of the front wheels, taking into account changes in wheel stroke and roll state of the vehicle body. Since the state is preserved,
As described above, straight-line stability is ensured while stabilizing the posture of the vehicle body.

In addition, since displacement of each camber angle θ above a certain level is prevented, there are no negative effects caused by changes in the camber angle, such as excessive camber angles that deteriorate initial turning performance or increase tire wear. There is no invitation.

Moreover, this camber angle control includes various corrections such as stroke change correction, roll camber angle correction, and load correction as second corrections, so that the camber angle control according to the vehicle speed and steering angle can be adjusted to the road surface. Changes in wheel stroke such as changes in vehicle body posture and vehicle height due to wheel bumps and rebounds caused by wind and other disturbances, acceleration/deceleration conditions, vehicle speed, etc.

It is always performed properly without being affected by changes in vehicle body roll or vehicle load.

On the other hand, when the vehicle is turning, the camber angle of each corner wheel is 0.
is controlled as follows according to the vehicle speed.

In other words, at low speeds (when the vehicle speed V is the set vehicle speed ■ or above and the set vehicle speed ■1 or less), the camber angle of the front wheel on the inside of the turn (JF
I is set to a constant value on the positive side, the camber angle θFO of the front wheel on the outside of the turn is set to a constant value on the negative side, the camber angle θR1 of the rear wheel on the inside of the turn is set to a constant value on the negative side, and the camber angle ORo of the rear wheel on the outside of the turn is set to a constant value on the negative side. is set to a constant value on the positive side.

In addition, at low and medium speeds (vehicle speed V is higher than the set vehicle speed 71 and lower than the set heavy speed ■2), the camber angle OFI of the front wheel on the inside of the turn is
is set to decrease from the positive side to the positive side as the speed increases, the camber angle OFO of the front wheel on the outside of the turn is set to increase from the negative side to the positive side as the speed increases, and the camber angle θRI of the rear wheel on the inside of the turn is set to The camber angle θRO of the rear wheel on the outside of the turn is set to increase from the negative side to the positive side as the speed increases, and to decrease from the positive side to the negative side as the speed increases.

In addition, at medium to high speeds (when the vehicle speed V is higher than the set vehicle speed 72 and lower than the set vehicle speed V3), the camber angle of the front wheels θFIy θ
Both FOs are set to the neutral state, the camber angle θRI of the rear wheel on the inside of the turn increases from the negative side to the positive side as the speed increases, and the camber angle θRO of the rear wheel on the outside of the turn increases from the positive side to the negative side as the speed increases. It is set to decrease to the side.

Furthermore, at high speeds (when the vehicle speed V is higher than the set vehicle speed 71), the camber angle θFry θFO of the front wheels are both set to the neutral state, and the camber angle θ of the rear wheel on the inside of the turn is set to the neutral state.
RI is set to a constant value on the positive side, and the camber angle θRO of the rear wheel on the outside of the turn is set to a constant value on the negative side.

Therefore, regarding the canvas thrust force that is applied to the turning grip force of the wheels, when turning at low speed, the canvas thrust force on the rear wheel side is relatively smaller than the canvas thrust force on the front wheel side, resulting in oversteer (or a slight oversteer tendency). This greatly improves turning performance, including the turning performance required at low speeds.

When turning at medium speeds, the canvas thrust force on the front wheel side decreases and remains at a constant value depending on the speed, but the canvas thrust force on the rear wheel side increases.

The steering characteristics change from oversteer to neutral steer and then to understeer. Therefore, depending on the speed, turning performance and running stability are properly ensured.

Furthermore, when turning at high speeds, the canvas thrust force on the rear wheels becomes relatively large compared to the canvas thrust force on the front wheels, resulting in understeer (or understeer tendency), which greatly improves the driving stability required at high speeds. do.

In particular, at medium speeds or above, the camber angle of the front wheels is set to neutral, and the desired steering characteristics are obtained by adjusting the camber angle of the rear wheels. Since no complicated behavior is caused in a certain front wheel, the control becomes stable and the control itself becomes easy.

Moreover, in the above-mentioned camber angle control, various corrections such as stroke change correction, roll camber angle correction, load correction, and steering correction are performed as the first correction, so the camber angle is adjusted according to the vehicle speed and steering angle. The angle control is based on wheel bumps and rebounds caused by disturbances such as road surface conditions and wind, wheel stroke changes such as changes in vehicle body posture and vehicle height due to acceleration/deceleration conditions, vehicle speed, etc., vehicle body roll, and vehicle movement. unaffected by changes in payload or turning steering itself.
Always done properly.

Furthermore, since the control of the camber angle θ of each wheel in this case is adjusted relatively smoothly according to changes in the steering angle δ, the above-mentioned improvement in driving performance can be achieved without impairing the steering feel. can be obtained.

Note that each map shown in FIGS.
The number is stored in the ROM 34 of the vehicle, but it is desirable to determine the number by experiment in accordance with the characteristics of the vehicle so as to obtain a high effect. Furthermore, it is desirable that each set vehicle speed, set steering angle, etc. be set to appropriate values in accordance with the characteristics of the vehicle.

In addition, in the maps ■ and ■ of FIGS. 4 and 5, the vertical axis (θ axis) is not the actual camber angle θ, but the camber angle θ of each wheel when it is stopped. It is also possible to set the magnitude of the adjustment amount from .

Furthermore, in the first correction or second correction described above, correction that takes into account changes in steering angle due to vehicle body roll (roll steering angle correction), and correction that takes into account changes in alignment due to lateral force (lateral force correction) may be added to each. In this case, the steering angle correction at the time of roll corrects the change in the steering angle due to the roll of the vehicle body. Regarding the roll, the roll angle φ can be calculated based on the detected value of the vehicle height sensor 36 of each wheel. Based on a previously known relationship between the roll angle φ and the steering angle, the steering angle change caused by the roll can be determined and corrected accordingly. Also,
Lateral force correction is used to compensate for alignment changes due to deformation of suspension bushings when lateral force is applied to the vehicle, and lateral force can be calculated based on the detection information of the separate speed sensor. Based on the previously known relationship between the lateral force and the camber angle, the alignment change caused by deformation of the suspension bushing or the like can be determined and corrected accordingly.

Furthermore, due to the movement of the center of gravity of the vehicle body that occurs when the vehicle body rolls, the stroke-camber angle characteristic changes, for example, as indicated by the chain line Q4 in FIG. Since it changes as shown by Q2, it is conceivable to make corrections taking into consideration such movement of the center of gravity of the vehicle body.

Alternatively, among the negative corrections mentioned above, depending on the characteristics of the vehicle, etc.
For cases where the effect of correction is small, it may be possible to omit correction.

In addition, if the range of camber angle control for each wheel is limited due to reasons such as the proximity of each wheel to a member on the vehicle body side, etc., the camber angle control should be performed only within the positive range. It is also possible to configure it so that it is executed only in the negative range, or to execute it in both the positive and negative ranges.

Furthermore, it is also possible to configure the system to perform camber angle control only for the front wheels or only the rear wheels, or to perform camber angle control only for wheels located on one diagonal line in plan view. . In this case, it is also possible to further provide (2) an actuator that performs camber angle control for only the front wheels or only the rear wheels, and to perform camber angle control for only one of the left and right wheels depending on the driving condition.

The controller 32 shown in FIG.
Therefore, by preparing a ROM that stores the required roll angle-camber angle map and vehicle speed-correction coefficient map, it can be applied to vehicles with different characteristics simply by replacing the ROM. can do.

Furthermore, in the above embodiment, the camber angle, which is one of the eye alignment elements, is controlled, but other eye alignment elements such as the toe angle and caster may also be controlled, and these alignment elements may also be controlled. It may be controlled in multiple ways.

In addition, although the suspensions in the above embodiments are all strut types, other types of suspensions can also be used to control the camber angle of the wheels by interposing an actuator between the wheel support member and the vehicle body. The present invention can be easily applied to any suspension. Further, the actuator is not limited to the hydraulic type as in the above embodiment, but it is also possible to use, for example, an electric type actuator.

Furthermore, such a wheel alignment control device may be used in combination with other traction devices, such as a four-wheel steering device or a parking power distribution device in a four-wheel drive system.

[Effects of the Invention] As detailed above, according to the wheel alignment control device of the present invention, in a vehicle equipped with front wheels and rear wheels, the wheel alignment control device is provided on one or both of the front wheels and the rear wheels to control the alignment. an actuator for adjusting the vehicle, a driving state detecting means for detecting the traveling state of the vehicle, a stroke detecting means for detecting the stroke position of the wheel, and a storage means for storing the relationship between the stroke position of the wheel and the alignment change;
and control means for controlling the actuator.

The control means includes a target alignment setting section for setting a target alignment of the wheels according to the running state of the vehicle detected by the running state detecting means, and a stroke position of the wheel detected by the stroke detecting means and the storage means. an alignment change calculation section that calculates an alignment change from the relationship between the wheel stroke position and the alignment change stored in the wheel; and an alignment change calculation section that calculates an alignment change with respect to the target alignment set by the target alignment setting section. The configuration includes a target alignment correction section that performs correction by the amount of correction, and an actuator control section that controls the actuator so that each wheel takes the corrected target alignment. The vehicle's driving performance, such as steering performance and straight-line driving performance, can be greatly improved from 2000 to high-speed driving ranges.In particular, since the alignment control amount is corrected according to changes in the wheel stroke, even if the vehicle is subjected to various disturbances, The alignment is always appropriately controlled, and the above-mentioned improvement in the driving performance of the vehicle can be reliably achieved.

[Brief explanation of drawings]

1 to 7 show a wheel alignment control device (camber angle control device) as an embodiment of the present invention. FIG. 3 is a flowchart explaining its operation, FIG. 4 is a diagram showing a vehicle speed-camber angle map (MAP I) stored in the ROM of the controller, and FIG. Figure 5 shows the vehicle speed-camber angle map (
6 is a diagram showing the relationship between the change in wheel stroke and the camber angle, and FIG. 7 is a diagram showing the relationship between the roll of the vehicle body and the camber angle. 2.4,6,8. A-Actuator for adjusting camber angle as alignment, 10,12°14.16.
---Electromagnetic control valve, 18--supply path, 20--
pump, 22-discharge path, 24--oil reservoir, 2
6.--Accumulator, 28-.-Relief valve, 30
-u dynamic circuit, 32-・controller as control means,
34--ROM in the controller 32 (storage means)
, 36--Vehicle height sensor, 38--Steering sensor (driving state detection means), 40--Vehicle speed sensor (driving state detection means), 42.44, 46.48--Displacement sensor, F
,--vehicle body, S-strut type suspension strut, W-wheel.

Claims (2)

[Claims] (1) In a vehicle equipped with front wheels and rear wheels, an actuator provided on one or both of the front wheels and the rear wheels to adjust the alignment thereof, a driving state detection means for detecting the driving state of the vehicle, and a wheel a stroke detection means for detecting a stroke position of the wheel; a storage means for storing a relationship between the stroke position of the wheel and an alignment change; and a control means for controlling the actuator; a target alignment setting unit that sets a target alignment of a wheel according to a detected running state of the vehicle, a stroke position of the wheel detected by the stroke detection means, a stroke position of the wheel and an alignment change stored in the storage means; an alignment change calculation unit that calculates an alignment change from the relationship between the target alignment change calculation unit and the target alignment correction unit that corrects the target alignment set by the target alignment setting unit by the alignment change calculated by the alignment change calculation unit; A wheel alignment control device comprising: an actuator control section that controls the actuator so that each wheel assumes the corrected target alignment. (2) The camber angle of the wheel is used as the wheel alignment, and the control means sets the target camber angle of the wheel in accordance with the running state of the vehicle detected by the running state detection means. A camber angle change in which a camber angle change is determined from a target camber angle setting unit, the stroke position of the wheel detected by the stroke detection means, and the relationship between the stroke position of the wheel and the change in camber angle stored in the storage means. a calculation section, a target camber angle correction section that corrects the target camber angle set by the target camber angle setting section by the camber angle change calculated by the camber angle change calculation section; and an actuator control unit that controls the actuator to take a target camber angle,
A wheel alignment control device according to claim 1.