JP3119286B2 - Vehicle suspension control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a suspension control device for a vehicle, and more particularly to a suspension control device for a vehicle which is suitable for achieving a balance between steering stability and ride comfort.

[0002]

2. Description of the Related Art Conventionally, vehicles equipped with a suspension control device are provided with an anti-squat control function for suppressing a squat phenomenon in which the rear portion of the vehicle lowers and the front portion of the vehicle rises when the vehicle suddenly starts or accelerates rapidly. As the anti-squat control, a technique of setting a higher damping force of the suspension mechanism based on the throttle opening speed (for example, see Japanese Patent Publication No. 2-14206).
Also, a technique has been developed in which the setting of the damping force of the suspension mechanism is changed based on whether or not the throttle opening exceeds a preset threshold value (single threshold value) and the magnitude of the vehicle speed. I have.

[0003]

However, in the above-mentioned prior art, the threshold value of the throttle opening is set to one, and the damping force of the suspension mechanism is changed based on the threshold value and the vehicle speed. In technology, for example, when the threshold value of the throttle opening is set so that the damping force of the suspension mechanism is optimal in the middle to low speed range, the throttle opening when the vehicle speed enters the high speed range is not Since the threshold value has already been exceeded, there has been a problem that the anti-squat control in the high-speed range cannot be performed accurately. On the other hand,
When the threshold value of the throttle opening is set so that the damping force of the suspension mechanism is optimal in a high-speed region, contrary to the above, the problem that the anti-squat control in a medium-low speed region cannot be accurately performed. was there.

[0004]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned disadvantages of the prior art. In particular, the present invention sets a plurality of threshold values for the throttle opening and sets the throttle opening to any one of the plurality of thresholds. By setting the damping force of the suspension mechanism higher for a predetermined time when the above becomes the case, it is possible to provide a vehicle suspension control device capable of suppressing the squat phenomenon at the time of sudden acceleration regardless of the vehicle speed, With that purpose.

[0005]

SUMMARY OF THE INVENTION According to the present invention, there is provided a throttle opening detecting means for detecting a throttle opening in response to an operation of an accelerator pedal of a vehicle equipped with a suspension mechanism, and a throttle opening detecting device which is set in a region where the throttle opening is large. Storage means for storing a plurality of threshold values such as threshold values set in an area where the threshold value and the throttle opening are small ; detection data of the throttle opening detection means; and storage of the storage means. Control means for controlling the damping force of the suspension mechanism based on the data, wherein the control means controls the throttle opening detected by the throttle opening detecting means and the plurality of thresholds stored in the storage means. A magnitude relationship determination function for determining a magnitude relationship with a value, and a detected throttle opening is equal to or greater than or equal to any one of the plurality of thresholds.
When the damping force of the suspension mechanism is
Set to a higher state for a while, and after the lapse of the predetermined time,
The damping force setting change function that sets the damping force to a lower state
Wherein each of the threshold values of the throttle opening is a vehicle
Setting the damping force of the suspension mechanism during acceleration
One of the reference values to be used as the change reference and
For changing the setting of the damping force of the suspension mechanism
Pair of thresholds having the other reference value for
And the other reference value is the one reference value.
It is configured to be set to a lower value . This aims to achieve the above-mentioned object.

[0006]

According to the present invention, a plurality of threshold values of the throttle opening are set in advance, and the control means includes a throttle opening detected by the throttle opening detecting means during running of the vehicle, and a storage means. The magnitude of the detected throttle opening is determined to be greater than or less than one of the plurality of thresholds.
When the damping force of the suspension mechanism is
After the specified time has elapsed, the attenuation
In order to set the power to a low state, regardless of the magnitude of the throttle opening accompanying the operation of the accelerator pedal by the vehicle driver, in other words, in which speed range the vehicle speed is in the middle-low speed range or the high speed range Regardless of this, it is possible to suppress a squat phenomenon in which the rear portion of the vehicle is lowered and the front portion of the vehicle is lifted by sudden depression of the accelerator pedal (when the vehicle is rapidly accelerated) or the like. This makes it possible to achieve both steering stability and ride comfort.

[0007]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing a vehicle suspension control apparatus according to an embodiment of the present invention;

First, the structure of a main part of a vehicle equipped with the vehicle suspension control device of the present embodiment will be described with reference to FIG.
A suspension mechanism 2 including a coil spring 4 and an actuator 5 is provided. A suspension mechanism 6 including an oil damper 7, a coil spring 8 and an actuator 9 is provided near the left front wheel, and near the right rear wheel. Is provided with a suspension mechanism 10 having an oil damper 11, a coil spring 12, and an actuator 13. A suspension mechanism 14 having an oil damper 15, a coil spring 16, and an actuator 17 is provided near the left rear wheel. Has been established.

Further, inside the vehicle 1, a steering sensor 18 for detecting a steering angle, a vertical acceleration sensor 19 for detecting a vertical acceleration acting on the vehicle body, a vehicle speed sensor 20 for detecting a vehicle speed, a vehicle driver A throttle sensor 21 for detecting a throttle opening degree based on an accelerator pedal depression operation, a brake switch 22 for detecting a brake operation state based on a vehicle driver's depression operation of a brake pedal, and an engine rotation speed signal. An ignition coil 23 and an electronic suspension controller 25 (hereinafter, abbreviated as a controller) for performing suspension control are provided.

Next, the configuration of the vehicle suspension control apparatus of the present embodiment will be described with reference to FIG. 1. A controller 25 is connected to a battery 28 via fuses 26 and 27.
And an ignition switch 30 via a fuse 29.
, A brake switch 22, a stop lamp 31 that lights up when the brake is operated, and an auto / sport switch 3.
2, DN switch 33 and ignition coil 23
, A noise filter 34, and a sport / auto lamp 3
5 are connected to each other.

Further, the controller 25 includes a vehicle speed sensor 20, a steering sensor 18, a vertical acceleration sensor 19, a throttle sensor 21, an engine control controller (EPI controller) 36, and oil dampers 3, 7, and 11. , 15 are set to predetermined states (“hard state”, “soft state”, and “medium state”), respectively.

The controller 25 determines the steering operation state based on the output signal of the steering sensor 18, determines the degree of vertical acceleration acting on the vehicle body based on the output signal of the vertical acceleration sensor 19, and determines the output signal of the vehicle speed sensor 20. , The degree of the throttle opening (unit [deg]) is determined based on the output signal of the throttle sensor 21, and the brake operation state is determined based on the output signal of the brake switch 22. ing.

Here, the features of this embodiment will be described. The controller 25 has a throttle opening of 40 [d
eg), each oil damper 3, 7, 11, 1
5 is set to the “soft state”, and when the throttle opening is 40 [deg] or more, each oil damper 3
7, 11, 15 damping force for 2 seconds "hard state"
When the throttle opening degree is not less than 55 [deg] and becomes 35 [deg] or less after the throttle opening degree becomes 40 [deg] or more, each oil damper 3 is set. , 7, 11, 15 are set to the "hard state" for 2 seconds, for example, and then returned to the "soft state".

When the throttle opening degree becomes 50 [deg] or less after the throttle opening degree becomes 55 [deg] or more, the controller 25 sets each of the oil dampers 3, 7, 11, 15.
For example, after setting the damping force to the "hard state" for 2 seconds, the damping force is returned to the "soft state" and the throttle opening is set to 50 [de].
g] or less, and when it becomes 35 [deg] or less, the damping force of each of the oil dampers 3, 7, 11, 15 is set to, for example, "hard state" for 2 seconds and then to "soft state". To return to. In this case, the throttle opening degree 55 [deg] is in a state close to full open.

FIG. 3 is a diagram showing the relationship between the threshold value of the throttle opening and the anti-squat control. In this embodiment, the threshold value of the throttle opening is set in two stages. That is, the threshold value of the throttle opening in the first stage is 40 [de] in the vehicle acceleration direction (the direction in which the accelerator pedal is depressed).
g], 35 in the vehicle deceleration direction (accelerator pedal return direction)
[Deg], and the threshold value of the second-stage throttle opening is set to 55 [deg] in the vehicle acceleration direction and 50 [deg] in the vehicle deceleration direction. The places indicated by circles in the figure are places where anti-squat control is executed.

In this case, the first-stage throttle opening threshold and the second-stage throttle opening threshold include:
As described above, the hysteresis is provided in the vehicle acceleration direction and the vehicle deceleration direction, thereby preventing the anti-squat control from being started at an unnecessary throttle opening. Further, since the throttle opening thresholds of the first stage and the second stage are also set in the vehicle deceleration direction (accelerator pedal return direction), the nose dive in which the nose portion of the vehicle lowers when the accelerator pedal is released. It is also possible to suppress the phenomenon.

The threshold value of the throttle opening at the first stage will be described. For example, when the vehicle driver depresses the accelerator pedal from a state where the throttle opening is 35 [deg] or less, the throttle opening becomes 40 [deg] or more. This shows how anti-squat control is performed in the event of a failure.
In this case, for example, when the accelerator pedal is depressed from a state where the throttle opening is 38 [deg], the throttle opening becomes 4 [deg].
Control is not performed even when the throttle opening reaches 3 [deg]. For example, when the throttle pedal is depressed from the state where the throttle opening is 33 [deg] and the throttle opening becomes 41 [deg], the control is performed.

The threshold value of the throttle opening in the second stage will be described. For example, when the vehicle driver depresses the accelerator pedal from a state where the throttle opening is 50 [deg] or less, the throttle opening becomes 55 [deg] or more. This shows how anti-squat control is performed in the event of a failure.
In this case, for example, when the accelerator pedal is depressed from a state where the throttle opening is 52 [deg], the throttle opening becomes 5 [deg].
The control is not performed even when 9 [deg] is reached. For example, when the throttle pedal is depressed from the state where the throttle opening is 47 [deg] and the throttle opening is 51 [deg], the control is performed.

That is, in this embodiment, the threshold value of the throttle opening is set in two stages as shown in FIG. 3 so that when the vehicle speed is in the middle to low speed region, the throttle in the first stage is set. The operation of each of the actuators 5, 9, 13, 17 is controlled based on the opening threshold value (35 to 40 [deg]) to bring the damping force of each of the oil dampers 3, 7, 11, 15 into a predetermined state. When the vehicle speed is in the high speed range, the second stage throttle opening threshold (50 to 55) is set.
[Deg]), each actuator 5, 9, 1
The operation of each of the oil dampers 3, 7, 1
The damping forces 1 and 15 are set to a predetermined state (see FIG. 4 described later). In this case, the above-described two-step throttle opening threshold values are stored in the memory 37 built in the controller 25 in advance.

Next, an example of suspension control in this embodiment configured as described above will be described with reference to FIG.

The controller 25 mounted on the vehicle 1
It is determined based on the output signal of the throttle sensor 21 whether the throttle opening is 40 [deg] or more (step S).
1) If the throttle opening is less than 40 [deg],
The damping force of each oil damper 3, 7, 11, 15 is controlled by controlling each of the actuators 5, 9, 13, 17 in a "soft state".
(Step S2). Thereafter, the process returns to the determination in step S1. On the other hand, when the throttle opening is equal to or more than 40 [deg], the controller 25 controls the actuators 5, 9, 13, 17 to control the oil dampers 3, 7,.
After setting the damping forces 11 and 15 to the “hard state” for 2 seconds, for example, the damping force is returned to the “soft state” (step S3). In this case, the controller 25 measures the time (two seconds) using a built-in timer.

Next, the controller 25 sets the throttle opening to 55 [d] based on the output signal of the throttle sensor 21.
[Eg] or less (step S4), and when the throttle opening is 55 [deg] or more, the actuators 5, 9, 13, 17 are controlled to control the oil dampers 3, 3, and 17, respectively.
7, 11, 15 damping force for 2 seconds "hard state"
Is returned to the "soft state" after the setting (step S
5).

Further, the controller 25 sets the throttle opening to 50 [d] based on the output signal of the throttle sensor 21.
eg] is determined (step S6).
If the throttle opening falls below 50 [deg],
The actuators 5, 9, 13, 17 are controlled to set the damping force of each of the oil dampers 3, 7, 11, 15 to, for example, a "hard state" for, for example, 2 seconds, and then return to a "soft state" (step S7).

Further, the controller 25 further increases the throttle opening degree by 35 based on the output signal of the throttle sensor 21.
[Deg] or less is determined (step S
8) When the throttle opening is 35 [deg] or less, the actuators 5, 9, 13, 17 are controlled to reduce the damping force of the oil dampers 3, 7, 11, 15 to, for example, 2 [deg.].
After setting to the "hard state" for a second, the state is returned to the "soft state" (step S9). Thereafter, the process returns to the determination in step S1.

On the other hand, if the throttle opening is less than 55 [deg] in the determination in step S4, the controller 25 determines whether or not the throttle opening is 35 [deg] or less based on the output signal of the throttle sensor 21. Is determined (step S10), and the throttle opening is 35 [deg].
If not, the process returns to the determination in step S4. On the other hand, if the throttle opening becomes 35 [deg] or less, the actuators 5, 9, 13, 17 are controlled to control the oil dampers 3, 7, respectively. , 11 and 15 are, for example, 2
After setting to the "hard state" for a second, the state is returned to the "soft state" (step S11). Thereafter, the process returns to the determination in step S1. The above is the flow of the suspension control in the present embodiment.

As described above, according to this embodiment, when the vehicle speed is in the middle to low speed range, each of the threshold values (35 to 40 [deg]) of the first stage throttle opening is used as a reference. When the damping force of the oil dampers 3, 7, 11, and 15 is set to a predetermined state, and the vehicle speed is in a high speed range, the second-stage throttle opening threshold value (50 to 55 [de
g]), each oil damper 3, 7, 11, 15
In order to set the damping force of the vehicle to a predetermined state, the squat that lowers the rear portion of the vehicle and lifts up the front portion of the vehicle when the vehicle suddenly starts or accelerates, regardless of whether the vehicle speed is in the middle speed range or the high speed range The phenomenon can be suppressed. Therefore, it is possible to achieve both steering stability and ride comfort.

According to this embodiment, the throttle opening threshold is set not only in the vehicle acceleration direction (accelerator pedal depression direction) but also in the vehicle deceleration direction (accelerator pedal return direction). It is possible to suppress the nose dive phenomenon in which the nose of the vehicle lowers during deceleration (when the accelerator pedal is released).

Further, according to this embodiment, the first-stage throttle opening threshold and the second-stage throttle opening threshold have hysteresis in the vehicle acceleration direction and the vehicle deceleration direction. Thus, it is possible to prevent the anti-squat control from being started at an unnecessary throttle opening.

In this case, in the present embodiment, the anti-squat control shown in FIG. 4 is performed. However, the anti-squat control includes a vehicle speed sensitive control (when the vehicle speed becomes equal to or higher than a predetermined vehicle speed, the damping force is set to "1"). It is also possible to combine the control for setting to the "medium state", and thereby the steering stability can be further improved. When the anti-squat control is combined with the vehicle speed sensitive control, both controls are performed independently, and the anti-squat control does not depend on the vehicle speed as described above.

In this embodiment, after the damping force of each of the oil dampers 3, 7, 11, and 15 is set to the "hard state" for 2 seconds in steps S3, S5, S7, S9, and S11 in FIG. Although the control for returning to the "soft state" was performed in the above, the time for maintaining the "hard state" is not limited to 2 seconds, and can be set to an arbitrary time (a short time in seconds). .

Further, in this embodiment, the threshold value of the throttle opening is set in two steps so as to correspond to each of the middle and low speed regions and the high speed region. It is also possible to set three stages so as to correspond to the respective speed ranges of the range, the middle speed range and the high speed range.

Further, in this embodiment, the threshold values of the throttle opening set in two stages are set to the numerical values (3
5 to 40 [deg], 50 to 55 [deg]), but the threshold value of the throttle opening is not limited to the numerical value.

[0033]

As described above, according to the vehicle suspension control apparatus of the present invention, a plurality of throttle opening thresholds are set, and the detected throttle opening is set to one of the plurality of thresholds. When the value exceeds or falls below the threshold
The damping force of the suspension mechanism is increased for a predetermined time.
And after the lapse of the predetermined time, the damping force is reduced.
The above thresholds are set when the vehicle accelerates.
For changing the setting of the damping force of the suspension mechanism
One of the reference values for
To set the damping force of the spence mechanism
Configured as a pair of thresholds having the other reference value
And the other reference value is lower than the one reference value.
Is set to For this reason, regardless of the magnitude of the throttle opening accompanying the accelerator pedal operation, in other words, regardless of whether the vehicle speed is in the middle to low speed range or the high speed range, when the vehicle is rapidly accelerated (the accelerator pedal is pressed). It is possible to suppress the squat phenomenon in which the rear portion of the vehicle lowers and the front portion of the vehicle floats up due to sudden depression of the vehicle, etc., and as a result, it is possible to achieve a balance between steering stability and ride comfort. be able to.

Further, Te vehicle suspension control system odor of the present invention, the time of rapid deceleration of the vehicles can also be suppressed nose dive phenomenon that the front side is lowered in the vehicle (when released suddenly the depression of the accelerator pedal) Can be achieved.

[Brief description of the drawings]

FIG. 1 is a control block diagram illustrating a configuration of a main part of a vehicle according to an embodiment of the present invention.

FIG. 2 is a schematic view showing a configuration of a main part of a vehicle in the embodiment.

FIG. 3 is a diagram showing a relationship between a threshold value of a throttle opening and anti-squat control in the embodiment.

FIG. 4 is a flowchart of suspension control in the embodiment.

[Explanation of symbols]

2,6,10,14 Suspension mechanism 3,7,11,15 Oil damper 4,8,12,16 Coil spring 5,9,13,17 Actuator 21 Acting as throttle opening detecting means Throttle sensor 25 Controller as control means 37 Memory as storage means

Claims (1)

(57) [Claims] 1. A vehicle equipped with a suspension mechanism.
A switch that detects the throttle opening according to the xel pedal operation
Rotor opening detection means and throttle openinglargeregion
Threshold and throttle openingsmallregion
Threshold set forofRecord that stores multiple thresholds
Storage means, and detection data and data of the throttle opening detection means.
And the suspension based on data stored in the storage means.
Control means for controlling the damping force of the throttle mechanism, wherein the control means detects
Throttle opening and the stored in the storage means.
Judgment of magnitude relationship with multiple thresholds
Function and the detected throttle opening degree
Above any thresholdOr when
A state in which the damping force of the suspension mechanism is increased for a predetermined time
After the specified time has elapsed, the damping force is set to a lower value.
And a damping force setting change function for setting Each of the threshold values of the throttle opening may be
For changing the setting of the damping force of the suspension mechanism
And one of the reference values for
To change the damping force setting of the suspension mechanism
As a pair of thresholds having the other reference value
And the other reference value is lower than the one reference value.
Value is set to Characteristic vehicle suspension
Control device.