JPH05213028A - Caster angle control device for vehicle - Google Patents

Abstract

PURPOSE:To control a caster angle in such a way as not causing the deterioration of riding comfort at the time of running on the rough area of a travel road by setting a large caster angle, so that the roughness of the travel road lowers input sensitivity for a vehicle, when the roughness is detected. CONSTITUTION:Compensation amount setting sections 26A to 26E are so constituted as to take in information from various types of sensors, including a preview sensor 29A (surface sensor) as a road surface condition detecting means, a steering angle sensor 29B, a travel speed sensor 29C, a lateral acceleration sensor 29D and a longitudinal acceleration sensor 29E. Upon receipt of roughness information from the preview sensor 29A, the sections 26A to 26E output a correction amount k1 for increasing a caster angle by an amount corresponding to a short time for each wheel to pass the rough area of a road, while considering a control lag. Then, the correction amount k1 is quickly reduced to zero, thereby ending a control operation to increase a caster angle for riding over a projection or other purposes.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control device for a caster angle in a vehicle suspension, and more particularly, it controls the caster angle so as to detect the unevenness of the road surface in advance and reduce the input sensitivity of the unevenness to the vehicle. And a caster angle control device for a vehicle.

[0002]

2. Description of the Related Art In automobiles, it is known that the running characteristics of the vehicle can be changed by adjusting the alignment of the suspension, and the caster angle (hereinafter also simply referred to as the caster) which is one of the suspension elements.
Is also proposed to improve the running performance of the vehicle.

The caster angle affects not only the straight running stability and steering performance of the vehicle, but also the suspension sensitivity to the input of road surface disturbance. That is, generally, when the caster angle is small, the road surface disturbance input sensitivity is high, but when the caster angle is large, the road surface disturbance input sensitivity is lowered.

[0004]

By the way, when traveling on a rough road, the lower the sensitivity of the suspension to the disturbance input, the better the riding comfort. Therefore, it is conceivable to perform control so that the caster angle is increased during traveling on a rough road to reduce the road surface disturbance input sensitivity. In this case, the determination as to whether the road is a bad road can be made by detecting the input state of the disturbance to the vehicle.

However, the above-mentioned control is effective when the entire traveling road is a bad road, but it is effective when the road surface has a single irregularity while traveling on a normal road. Can't handle. In other words, if the unevenness of the road surface is detected from the input state of the disturbance to the vehicle, the vehicle will already get over the unevenness of the road surface at the time of detection, and control will not be in time.

The present invention has been devised in view of such a problem, and if the traveling road surface of the vehicle has irregularities, the caster angle can be controlled so as not to impair the riding comfort of the vehicle when riding over these irregularities. An object of the present invention is to provide a caster angle control device for a vehicle.

[0007]

Therefore, the caster angle control device for a vehicle according to the present invention has a caster angle adjusting mechanism capable of adjusting the caster angle by driving the constituent elements of the suspension of the vehicle, and the traveling of the vehicle. The caster angle is set according to the state, and the caster angle of the vehicle is provided with control means for controlling the caster angle adjusting mechanism so that the caster angle takes the set caster angle, and the unevenness of the traveling road surface in front of the vehicle is provided. When the road surface condition detecting means detects the unevenness of the traveling road surface, the control means sets a large caster angle so as to reduce the input sensitivity to the vehicle of the unevenness of the road surface. It is characterized by being configured as follows.

[0008]

In the above-described vehicle caster angle control device of the present invention, when the road surface condition detecting means detects the unevenness of the traveling road surface in front of the vehicle, the caster angle setting section inputs the unevenness of the road surface to the vehicle. A large caster angle is set to reduce the sensitivity, and the caster angle adjusting mechanism is controlled so that the set caster angle is obtained. Therefore,
When the vehicle gets over the unevenness of the road surface, the caster angle becomes large, and the input sensitivity of the unevenness of the road surface to the vehicle decreases.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A caster angle control device for a vehicle as an embodiment of the present invention will be described below with reference to the drawings.
2 is a block diagram showing the configuration of essential parts thereof, FIG. 2 is a perspective view showing a suspension provided with the caster angle adjusting mechanism, FIG. 3 is an exploded perspective view showing the caster angle adjusting mechanism, and FIG. 4 is a view showing the caster angle adjusting mechanism. Hydraulic circuit configuration diagram, FIG. 5 is a flow chart for explaining the operation, FIGS. 6 to 10 are maps relating to the setting of the control amount (correction amount) in the control of this device,
11 is a schematic side view of a wheel portion for explaining the operation, and FIGS. 12 and 13 are schematic plan views of the wheel portion for explaining the operation.

First, the suspension of a vehicle equipped with the present device will be described. The suspension of this embodiment is a strut-type front suspension for passenger cars, as shown in FIG.
As is well known, each is configured by combining a coil spring 3 with a shock absorber 2, and the heads of the struts 1 and 1 are fixed to the vehicle body 4 side. A front wheel 7 is rotatably attached to the lower ends of the struts 1, 1 via a knuckle 5 and a hub 6.

The lower end of the strut 1 is connected via a lower arm 8 to a cross member 9 provided between the front wheels so as to also serve as a sub-frame, and the shock absorber 2 is used as a part of a suspension link. Is composed of. Incidentally, 10 is a center member provided on the cross member 9, and 11 is a disc brake.

Then, the caster angle can be freely adjusted by sliding the heads 1A and 1A on the mounting portions of the heads 1A and 1A of the struts 1 and 1 in the front-rear direction of the vehicle body 4, respectively. Mechanisms 12 and 12 are provided. In addition, 27 is a drive shaft and 28 is a stabilizer. This caster angle adjusting mechanism 12, 12
Each of the wheels has the same structure, and as shown in FIG. 3, the slide base 14 attached to the vehicle body 4 side of the upper surface of the strut tower and the slide base 14 attached to the upper end of the strut 1 with respect to the slide base 14. And a slide plate 13 that can slide.

The slide base 14 has a structure in which a substantially rectangular through hole 16 parallel to the longitudinal direction of the vehicle body is provided in the center of a plate member 15 with its long side facing the longitudinal direction of the vehicle body. A pair of rail portions 17, 17 formed of walls having a substantially triangular cross section are erected in parallel on the entire two sides corresponding to the vehicle width direction side of 16. The rail portions 17, 17 are arranged inward, and the head portion 1A of the strut 1 penetrates between the rail portions 17, 17 facing each other and the inside of the through hole 16. In addition, 17a is a rib for supporting the rail portion 17.

On the other hand, the slider plate 13 has a substantially rectangular plate member 18 having a size corresponding to the distance between the rail portions 17 of the slide base 14, and two parallel sides of the plate member 18 on the rail portion side. The rail part 17 provided on the whole,
17 and sliding wall portions 19, 19 each having a wedge shape that can be inserted and inserted. The sliding wall portions 19, 19 have a wedge-shaped cross section, for example, a symmetrical triangular wall having a side of the plate member 18 as a top is integrally provided on a side portion of the plate member 18, and the above-mentioned rails. The slide plates 13 are in slidable contact with the rails 17, 17 without rattling.
The rails 17, 17 are guided between the rails 17 and 17 so that they can slide in a fixed direction.

A needle roller bearing 20, which is formed by arranging a plurality of roller bearings in parallel, is interposed between each sliding wall portion 19 and the rail portion 17 facing the sliding wall portion 19 along the sliding direction. Is stabilized along the longitudinal direction of the vehicle body so that it can slide smoothly. Further, in FIG. 3, reference numeral 21 denotes a bearing rolling surface provided on each of four outer surfaces of the sliding wall portion 19, which is a rectangular recess.

The upper end of the strut 1 is inserted through the slide base 14 into a circular opening 13a provided at the center of the slide plate 13. Further, while fixing holes 22 and 22 are provided in front of and behind the opening 13a, a pair of (two) mounting bolts 23 and 23 are projectingly provided on, for example, an insulator portion 1a of the head 1A of the strut 1 to fix the fixing holes 22 and 22. The head portion 1A of the strut 1 is integrated with the slider plate 13 by fastening these mounting bolts 23, 23 to each other. As a result, the casters of the front suspension can be changed by sliding the slider plate 13 in the front-rear direction.

Reference numeral 24 denotes a nut for fastening the strut head. And such a slide mechanism 1
An actuator (driving device) 25 for moving the strut head in the vehicle front-rear direction is directly connected to each of the slide plates 13 and 12. As the actuator 25, for example, as shown in the figure, a hydraulic cylinder 25B is a hydraulic pressure supply / discharge system 2 having a hydraulic switching valve such as a solenoid valve.
A hydraulic type that is driven through 5A is conceivable.

In this case, for example, a hydraulic circuit configuration as shown in FIG. 4 can be considered. 4, 25a is a tank for storing hydraulic oil, 25b is a pump, 25c is a pump accumulator, 25d and 25e are main accumulators, 25f is a filter, 25g is a relief valve, 25
h is a check valve, 25i, 25j, 25k, 25l
Is a control valve, 25m and 25n are position sensors, and other symbols are the same as those described above.

A controller (comprising a microcomputer and its peripheral circuits) 26 as a control means is connected to the actuator 25, and the controller 26 operates the actuator 25 based on information information from various sensors 29. To adjust the caster angle. That is, as shown in FIG.
The controller 26 is provided with correction amount setting units 26A to 26E for setting a correction amount relating to a control amount for each wheel. These correction amount setting units 26A to 26E are, for example, previews as road surface state detecting means. Information from various sensors 29 such as a sensor (road surface sensor) 29A, a steering angle sensor (steering angle sensor) 29B, a vehicle speed sensor 29C, a lateral acceleration sensor 29D, and a longitudinal acceleration sensor 29E is taken in. The preview sensor 29A
For example, the ultrasonic sensor is arranged in front of the vehicle body and inclined downward, and is provided for each of the left and right wheels.

The correction amount setting unit 2 for reducing the disturbance sensitivity
6A includes a preview sensor 29A and a vehicle speed sensor 29.
The information from C is taken in, and the correction amount setting unit 26A
Then, when the preview sensor 29A detects the unevenness of the road surface, the correction amount K ₁ is set so as to increase the caster angle in order to reduce the sensitivity to disturbance.

In particular, the correction amount K ₁ is set according to the magnitude of the vehicle speed V according to a map as shown in FIG. 6, for example. In the map of FIG. 6, the correction amount K ₁ increases in proportion to the magnitude of the vehicle speed V. This is because the higher the vehicle speed V, the greater the sensitivity to disturbance. The sensitivity is reduced. Incidentally, at the time of turning because may impair rather turning performance by increasing the caster angle, the correction amount K ₁ to increase the caster angle is set only when traveling straight, during turning to the K ₁ to 0.

By the way, the disturbance sensitivity can be reduced by increasing the correction amount K ₁ to increase the caster angle, which will be described with reference to FIGS. 11 to 13, K is the kingpin axis, P is the road surface grounding point of the tire, and W is
Is a wheel, a is a kingpin offset to the ground (distance in the vehicle width direction between the kingpin axis K on the road surface and the road surface grounding point P of the tire), and b is trail (the kingpin axis K on the road surface and the road surface grounding point P of the tire). In the vehicle longitudinal direction), θ is the caster angle, Fz is the vertical force acting on the kingpin axis, Fx is the longitudinal force acting on the kingpin axis, Fy is the lateral force (lateral force) acting on the kingpin axis, Mz. Is the vertical force component of the moment about the kingpin axis, Mx is the longitudinal force direction component of the moment about the kingpin axis, and My is the restoring moment about the kingpin axis due to the tire lateral force.

First, considering the moment around the kingpin axis, considering the vertical force direction component Mz and the longitudinal force direction component Mx, Mz = Fz.sin.theta.a Mx = Fx.a Therefore, the entire moment around the kingpin axis is obtained. M is M = Mx−Mz = a (Fx−Fz · sin θ) Normally, Fx> Fz · sin θ. Therefore, the larger the caster angle θ, the smaller the moment M about the kingpin axis, and the stability of the wheel W becomes. As a result, the disturbance sensitivity of the wheels W, that is, the influence of disturbance, can be reduced, and the riding comfort of the vehicle can be improved.

By the way, the wheel W may be steered as shown in FIG. 13 due to a road surface disturbance. At this time, a restoring moment My about the kingpin axis is generated by the lateral force Fy. The restoring moment My is: My = Fy · b ′ Note that b ′ is b ′ = b ± c · sin δ · tan δ, where c is c ² = a ² + b ² and the steering angle due to disturbance is δ. However, since δ is very small, it is considered that b′≈b.

Therefore, the larger the trail b, the larger the restoring moment My, and the larger the caster angle θ, the larger the trail b. Therefore, the larger the caster angle θ, the greater the stability against disturbance. Therefore, the disturbance sensitivity of the wheel W, that is, the influence of the disturbance can be reduced, and the riding comfort of the vehicle can be improved. Then, the output of the correction amount K ₁ is performed for a predetermined time (short time) immediately after the preview sensor 29A detects the unevenness of the road surface (after a minute required time). In other cases, the correction amount K ₁ is output.
_{As for 1} , 0 is output.

In particular, when the unevenness detection information (ON information) of the preview sensor 29A is entered, a correction amount K ₁ for increasing the caster angle θ for a short time in which each wheel rides on the unevenness is output while considering the control delay. Then, after this, it is desirable that the correction amount K ₁ is quickly set to 0 and the control for increasing the caster angle θ for overcoming the protrusion and the like is ended.

To this end, when the preview sensor 29A outputs the ON information, the timing at which the front wheel or the rear wheel of the corresponding wheel (that is, the right wheel or the left wheel) gets over the unevenness is estimated according to the vehicle speed V. Then, the correction amount K ₁ for increasing the caster angle θ may be output in accordance with this timing. Further, the correction amount setting unit 2 that sets the correction amount K ₂ corresponding to the steering angle (steering wheel angle) θ
Information from the steering angle sensor 29B is taken into 6B, and the correction amount K ₂ is set according to the size of the steering angle θ according to a map as shown in FIG. 7, for example.
In the map of FIG. 7, the correction amount K ₂ decreases in proportion to the magnitude of the steering angle θ, but this is because the steering performance is generally better when the caster angle is smaller. The negative correction amount K ₂ is set so as to gradually reduce the caster angle in response to the above. Incidentally, the correction amount K ₂ is for the cornering stability, the correction amount K ₂ to reduce the caster angle is set only during turning, the straight running K ₂
To 0.

Information from the vehicle speed sensor 29C is fetched into the correction amount setting section 26C for setting the correction amount K ₃ corresponding to the vehicle speed V, and the magnitude of the vehicle speed V is calculated according to a map as shown in FIG. The correction amount K ₃ is set according to In the map of FIG. 8, the correction amount K ₃ increases in proportion to the magnitude of the vehicle speed V.
This is because, generally, the larger the caster angle, the better the running stability (straightness stability), and the higher the speed, the more the running stability is required. Incidentally, the correction amount K ₃ is intended for straight running stability, the correction amount K ₃ to increase the caster angle is set only during straight, the K ₃ to 0 at the time of turning.

Information from the lateral acceleration sensor 29D is fetched into the correction amount setting section 26D for setting the correction amount K ₄ corresponding to the lateral acceleration (lateral G) G _Y , as shown in FIG. 9, for example. According to the map, the magnitude of the lateral acceleration G _Y (= |
The correction amount K ₄ is set according to G _Y |). In the map of FIG. 9, the correction amount K ₄ is the lateral acceleration G _Y is generated first a negative value decreases according to the increase of the lateral acceleration G _Y, reaches a certain lateral acceleration G _Y value,
This time, it increases as the lateral acceleration G _Y increases and becomes a positive value, and after the lateral acceleration G _Y reaches a certain value, it becomes a positive constant value.

In the region where the lateral acceleration G _Y is small (the range indicated by a in the figure), the correction amount K ₄ is decreased as the lateral acceleration G _Y increases. This is because the steering performance (steering ability) is reduced by reducing the amount. Moreover, further (in the drawing, the range indicated by b) is substantially linearly increasing the correction amount K ₄ according the lateral acceleration G _Y is large lateral acceleration G _Y is increased to the lateral acceleration G _Y is increased This is to make it easier for the driver to feel the fact and to ensure the running stability of the vehicle. This makes it difficult for the driver to bend as the lateral acceleration G _Y increases (for example, the handle becomes heavier), so that the driver can linearly feel the magnitude of the lateral acceleration G _Y.

Further, when the lateral acceleration G _Y becomes larger than this, the correction amount K ₄ is made substantially constant, in order to inform the driver that the magnitude of the lateral acceleration G _Y has increased to the limit. Is. As a result, the lateral acceleration G
_When the magnitude of _Y approaches the limit, the running stability of the vehicle decreases as the lateral acceleration G _Y increases, so that the driver can realize that the lateral acceleration G _Y is near the limit.

[0032] Incidentally, the correction amount K ₄ is for the time of turning of the lateral acceleration occurs, wherein the correction quantity K ₄ is set only when turning, the K ₄ to 0 at the time of straight. Further, the correction amount setting unit 26E for setting a correction amount K ₅ corresponding to the longitudinal acceleration (longitudinal G) G _F, it is populated with information from the longitudinal acceleration sensor 29E, for example, front and rear in accordance with the map shown in FIG. 10 The correction amount K ₅ is set according to the magnitude of the acceleration G _F.

In the map of FIG. 10, the correction amount K ₅ increases so as to be proportional to the magnitude of the longitudinal acceleration G _F (= | G _F |). This is because it is desired to secure the stability of straight running and the steering response (stability of the steering wheel). As described above, generally, the larger the caster angle, the better the running stability (straight stability) and the steering response (stability of the steering wheel). It is used to ensure the feeling.

Then, in the controller 26, the correction amounts K ₁ to K set by the correction amount setting units 26A to 26E are set.
A caster angle setting unit 26F that receives the K ₅ and corrects the initial caster angle φ ₀ to set the target caster angle φ is provided. The caster angle setting unit 26F is adapted to set the caster angle φ based on the following equation.

Φ = (1 + K ₁ + K ₂ + K ₃ + K ₄ + K ₅ ) φ ₀ (1) Since the caster angle control device for a vehicle as one embodiment of the present invention is configured as described above, For example, as shown in FIG. 5, the caster angle is set for each wheel. That is, first, immediately after the ignition switch of the automobile is turned on, parameters related to the control are initially set (step S1), and the presence of the road surface unevenness K, the steering angle θ, the vehicle speed V, the lateral acceleration G _Y, and the longitudinal acceleration G _{F are} related. The detection signal is read from each of the sensors 29A to 29E (step S
2).

As is smaller than a running straight, | [0036] In the next step S3, the steering angle theta threshold near 0 | determines whether less than the steering angle theta threshold | | θ ₀ θ ₀
If the steering angle θ is not smaller than the threshold value | θ ₀ |
Go to. When the process proceeds to step S4, it is determined whether the signal from the preview sensor (road surface sensor) 29A is on. If the signal from the preview sensor 29A is on, the process proceeds to step S5, and the correction amount K for reducing the disturbance sensitivity is set.
For example, ₁ is set according to the vehicle speed V using a map as shown in FIG. If the signal from the preview sensor 29A is not on, the process proceeds to step S6, and the correction amount K ₁ is set to 0 so that the disturbance sensitivity reduction control is not performed.

Furthermore, whether these steps S5 or S6
Then, the process proceeds to step S7 and the correction amount K ₂, K_FourSet to 0
Then, the process proceeds to step S8 and the correction amount K₃Is shown in FIG.
The map is set according to the vehicle speed V using such a map. one
If step S9, the correction amount K₁, K₃0
Set, and proceed to step S10 to set the correction amount K₂The figure
Set according to the steering angle θ using the map shown in 7.
It Then, the process proceeds to step S11 and the correction amount K_FourThe figure
Lateral acceleration G using the map shown in 9_YIn response to the
Set.

Steps S4 to S8 or Steps S9 to S
When the correction amounts K _{1 to} K ₄ are set in step 11, step S
In step 12, the correction amount K ₅ is set according to the longitudinal acceleration G _F using the map as shown in FIG. further,
In step S13, the caster angle setting unit 26F sets the target caster angle φ by correcting the initial caster angle φ ₀ according to the above equation (1) based on these correction amounts K _{1 to} K ₅ .

The operations of steps S2 to S13 are carried out every predetermined control cycle, and the caster angle is sometimes properly controlled according to the traveling state of the vehicle and the state of the road surface on which the vehicle is traveling. Then, the controller 26 controls the actuator 25 so that the actual caster angle becomes the target caster angle φ set in this way, and the slider plates 13, 13 are driven forward or backward by the actuator 25. The casters are adjusted.

Therefore, the correction amount K ₁ reduces the disturbance sensitivity of the suspension to the unevenness of the road surface and improves the riding comfort of the vehicle. In particular, the sensitivity to disturbance tends to increase as the vehicle speed V increases, but the correction amount K ₁
Is increased in proportion to the vehicle speed V, so that the disturbance sensitivity is sufficiently reduced even at a high speed, and the riding comfort of the vehicle is improved.

The disturbance sensitivity reduction control by the correction amount K ₁ is performed for a predetermined time (short time) in accordance with the timing when each wheel gets over the unevenness immediately after the preview sensor 29A detects the unevenness of the road surface (after a minute required time). Since it is performed only for a period of time), and after that, the process is quickly completed, so that it is possible to quickly enhance the effect of other control (control with other correction amounts K _{2 to} K ₄ ) after overcoming unevenness.

When the road surface frequently has irregularities in the information from the preview sensor 29A, for example, the ON information from the preview sensor 29A per unit time is used to judge this and the irregularities continuously exist. It is also conceivable that the correction amount K ₁ for increasing the caster angle in accordance with the vehicle speed V is continuously output by determining that the road is a bad road.

Further, the correction amount K ₂ improves the steering performance during steering, and the correction amount K ₃ improves the running stability (straight running stability) during straight running. Furthermore, the correction amount K
₄ , the steering performance (steering ability) is improved in a region where the lateral acceleration G _Y is small (the range indicated by a in the figure),
In a region where the lateral acceleration G _Y is large to some extent (a range indicated by b in the figure), it becomes easy for the driver to feel that the lateral acceleration G _Y becomes large, and the traveling stability of the vehicle is secured. Further, when the magnitude of the lateral acceleration G _Y increases to the limit, it becomes easier for the driver to recognize this.

Further, the correction amount K ₅ ensures traveling stability (straightness stability) and steering response (stability of the steering wheel) during acceleration / deceleration. In addition, each of the above maps (FIGS. 6 to 10)
The reference) is an example, and various map modes can be considered based on the characteristic tendency of each map.

[0045]

As described above in detail, according to the caster angle control device for a vehicle of the present invention, the caster angle adjusting mechanism capable of adjusting the caster angle by driving the components of the suspension of the vehicle, and the vehicle. And a control means for controlling the caster angle adjusting mechanism so that the caster angle of the vehicle is set to the set caster angle according to the traveling state of the vehicle and the traveling road surface in front of the vehicle. Equipped with road surface condition detection means to detect the unevenness of
When the control means is configured to set a large caster angle so as to reduce the input sensitivity to the vehicle of the unevenness of the traveling road surface when the unevenness of the traveling road surface is detected by the road surface state detecting means, When overcoming the unevenness existing on the traveling road surface, there is an advantage that the influence of the unevenness on the vehicle due to the disturbance is reduced and the riding comfort of the vehicle can be greatly improved.

[Brief description of drawings]

FIG. 1 is a block diagram showing a main configuration of a caster angle control device for a vehicle as an embodiment of the present invention.

FIG. 2 is a perspective view showing a suspension provided with a caster angle adjusting mechanism of a vehicle caster angle control device as one embodiment of the present invention.

FIG. 3 is an exploded perspective view showing a caster angle adjusting mechanism of a vehicle caster angle control device as one embodiment of the present invention.

FIG. 4 is a hydraulic circuit configuration diagram of a caster angle adjusting mechanism of a vehicle caster angle control device as one embodiment of the present invention.

FIG. 5 is a flowchart illustrating an operation of the caster angle control device for a vehicle as an embodiment of the present invention.

FIG. 6 is a map relating to setting of a control amount (correction amount) in the vehicle caster angle control device as one embodiment of the present invention.

FIG. 7 is a map relating to setting of a control amount (correction amount) in the vehicle caster angle control device as one embodiment of the present invention.

FIG. 8 is a map relating to setting of a control amount (correction amount) in the vehicle caster angle control device as one embodiment of the present invention.

FIG. 9 is a map relating to setting of a control amount (correction amount) in the vehicle caster angle control device as one embodiment of the present invention.

FIG. 10 is a map relating to setting of a control amount (correction amount) in the vehicle caster angle control device as one embodiment of the present invention.

FIG. 11 is a schematic side view of a wheel portion for explaining the operation of the vehicle caster angle control device as one embodiment of the present invention.

FIG. 12 is a schematic plan view of a wheel portion for explaining the operation of the vehicle caster angle control device as one embodiment of the present invention.

FIG. 13 is a schematic plan view of a wheel portion for explaining the operation of the vehicle caster angle control device as one embodiment of the present invention.

[Explanation of symbols]

1 strut 1A head of strut 1 1a insulator part 2 shock absorber 3 coil spring 4 vehicle body 5 knuckle 6 hub 7 front wheel 8 lower arm 9 cross member 10 center member 11 disc brake 12 caster angle adjusting mechanism (slide mechanism) 13 slide plate 13a opening 14 Slide Base 15 Plate Member 16 Through Hole 17 Rail Part 17a Rail Part 18 Plate Member 19 Sliding Wall Part 20 Needle Roller Bearing 22 Fixing Hole 23 Mounting Bolt 24 Nut 25 Actuator (Drive Device) 25A Hydraulic Supply / Discharge System 25B Hydraulic Cylinder 25a Tank 25b Pump 25c Pump accumulator 25d, 25e Main accumulator 25f Filter 25g Relief valve 25h Check valve, 25i, 25j, 5k, 25l Control valve 25m, 25n Position sensor 26 Controller 26A-26E Correction amount setting section 27 Drive shaft 28 Stabilizer 29 Sensor 29A Preview sensor (road surface sensor) 29B as road surface condition detecting means 29B Steering angle sensor (rudder angle sensor) 29C Vehicle speed Sensor 29D Lateral acceleration sensor 29E Longitudinal acceleration sensor

 ─────────────────────────────────────────────────── ─── Continued Front Page (72) Inventor Takao Morita 5-3-8, Shiba, Minato-ku, Tokyo Inside Mitsubishi Motors Corporation

Claims (1)

[Claims] 1. A caster angle adjusting mechanism capable of adjusting a caster angle by driving a constituent element of a vehicle suspension, and a caster angle set according to a running state of the vehicle so that the caster angle of the vehicle is set to this value. The control means for controlling the caster angle adjusting mechanism so as to obtain the caster angle, and the road surface state detecting means for detecting unevenness of the traveling road surface in front of the vehicle. A caster angle control device for a vehicle, which is configured to set a large caster angle so as to reduce the input sensitivity of the unevenness of the road surface to the vehicle when the unevenness of the traveling road surface is detected by the detection means. ..