JPH03243412A - Suspension controller - Google Patents

Abstract

PURPOSE:To prevent pitching motion from advancing by controlling so that a gain is zero and anti-pitch control by a rate of change in acceleration between front and rear which is obtained by a detection signal of a front and rear acceleration sensor is not performed when a vehicle lurches on a rough portion during running at a constant speed. CONSTITUTION:A means 7 for supplying/exhausting fluid to/from vehicle height adjusting cylinders 4a, 4b provided on respective front and rear wheels 2a, 3b is equipped with proportional flow rate control valves 11a, 11b in the middle of a discharged pipe of a pump 9 wherein the valves are controlled by a controller 15. The controller 15 calculates a rate of change in acceleration from output data of a front and rear acceleration sensor 14, calculates a control signal multiplying the rate by a desired gain, and controls anti-pitches of a vehicle. In this case, whether or not a detected value of an accel sensor 16 or the rate of change is smaller than a pre-specified threshold value is judged, and when the above is judged to be true, the above gain is made to be zero and anti-pitch control is stopped.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a suspension control device that controls the attitude of a vehicle.

(Prior Art) Generally, when the accelerator, brake, or steering wheel is suddenly operated while a vehicle is running, the vehicle body undergoes attitude changes such as pitch (type, squat) or low link (roll or yaw). Various suspension control devices have been proposed for automatically suppressing such changes in the posture of the vehicle body and improving the steering stability and ride comfort of the vehicle.

An example of such a suspension control system is shown in FIGS. 15 and 16. This suspension control device performs anti-pitch control, and in Fig. 1, 1 indicates the vehicle body, and between the vehicle body 1 and the axles 3a, 3b of the front and rear wheels 2a, 2b, there is a vehicle height adjustment device. The front and rear cylinders 4a and 4b are interposed,
Inside each cylinder 4a, 4b is a damping cap 5a, 5b.
are connected to accumulators 6a and 5b, which are spring elements.

Further, each cylinder 4a, 4b is connected to a supply/discharge means 7 for supplying and discharging a fluid such as oil, and this supply/discharge means 7 is connected to a reservoir tank 8 for storing fluid, and a reservoir tank 8 for storing fluid. a pump 9 that pressure-feeds the fluid (oil liquid) inside;
A main accumulator 10 that holds the pressure fluid pumped from the pump 9 at a constant pressure, and a front side provided with supply and discharge solenoids SP, S, which are disposed in the middle of the connection path between each cylinder 4a, 4b and the pump 9. , rear proportional flow control valves 11a and llb. In addition,
Although not shown, the supply/discharge means 7 is provided with a control means for controlling the operation of the pump 9 so that the pressure on the main accumulator 10 side is always at a predetermined value.

Moreover, a pressure sensor 1 is provided in the middle of the connection path between the cylinders 4a and 4b and the proportional flow control valves 11a and llb on the front and rear sides.
2a and 12b are connected to detect the pressure of the pressure fluid inside the cylinders 4a and 4b.

Front and rear vehicle height sensors 13a and 13b are interposed between the vehicle body 1 and the axles 7a and 7b. ring 2a,
The vehicle height at position 2b is detected.

Further, a longitudinal acceleration sensor 14 is attached to the vehicle body l, and is adapted to detect longitudinal acceleration α8 acting on the vehicle body l.

Reference numeral 15 indicates a controller that controls the supply/discharge means 7. This controller 15 controls the front and rear proportional flow control valves 1.
The instantaneous flow rate-current value characteristics of 1a and llb are stored in advance, and the detection signals of the vehicle height sensors 13a and i3b, the longitudinal acceleration sensor 14, and the pressure sensors 12a and 12b are inputted to perform arithmetic processing as described later. Car
Front and rear cylinders 4 necessary to control the posture of
Calculate the instantaneous flow rate q to obtain the supply and discharge amounts of a and 4b, and calculate the supply and discharge current values IP and IR corresponding to this instantaneous flow rate q.
are read from the stored data and output to the supply and discharge solenoids 5PSR of the front and rear proportional flow control valves 11a and llb, respectively.

The arithmetic processing contents of this controller 15 will be explained with reference to FIG. 16.

When this controller 15 inputs the signal of the longitudinal acceleration α8 detected by the longitudinal acceleration sensor 14, it differentiates this signal to obtain the longitudinal acceleration change rate, and then multiplies this by the gain to obtain the longitudinal acceleration change rate. Calculate the proportional instantaneous flow rate q. Then, it generates signals indicating -q and +q, applies these signals to the stored data for the front and rear proportional flow control valves 11a and 11b, reads out the corresponding current value, and applies this to the front and rear proportional flow control valves 11a and llb. It outputs to the flow rate control valves 11a and llb.

The controller 15 also stores target vehicle heights at the positions of the front and rear wheels 2a and 2b for feedback control. Then, the target vehicle height and front side,
The deviation from the detection signals of the rear vehicle height sensors 13a and +3b is taken, and the deviation of the actual vehicle height from the target vehicle height after control is adjusted using the signals indicating -q and +9.

In the suspension control device configured as described above, when the vehicle is running at a constant speed and the vehicle decelerates by operating the accelerator or brake, the vehicle body is configured to detect the deceleration direction (in this case, the deceleration direction). For pitching, which will be described later, the forward direction is assumed to be positive). The longitudinal acceleration sensor 14 detects this longitudinal acceleration α8 and outputs it to the controller. The controller has longitudinal acceleration α
Figure 17(b) Calculate the longitudinal acceleration change rate α8 from 8.
), a flow rate proportional to this longitudinal acceleration change rate &8 is calculated, and a current value corresponding to this is outputted to the front and rear proportional flow control valves 11a and llb. As a result, pressure fluid is supplied to and discharged from the front and rear cylinders 4a and 4b, respectively, thereby preventing tightness from occurring. Further, during acceleration, the operation proceeds in the same manner as described above, and this time, pressure fluid is discharged and supplied to the front and rear cylinders 4a and 4b, respectively, to prevent squat from occurring.

(Invention or problem to be solved) By the way, when a vehicle travels on an uneven road surface,
makes a pitching motion. In this case, the above-mentioned suspension control device detects the longitudinal acceleration (hereinafter referred to as
The acceleration that acts on the vehicle body 1 due to the pitching motion and rolling (roll and yaw) motion caused by road surface conditions is called the apparent acceleration.In contrast, the acceleration that is applied to the vehicle body 1 due to the pitching motion and rolling (roll and yaw) motion that occur due to road conditions etc. is called the apparent acceleration. For convenience, the acceleration generated due to throttle operation, clutch operation in the case of a vehicle with a clutch, etc. is referred to as true acceleration.

), and this apparent acceleration is in the opposite direction to the true acceleration used to prevent pitching, which is in the same direction as the pitching motion that causes the apparent acceleration.
I ended up making the pinching bigger instead. This will be explained using an example where a vehicle is traveling at a constant speed and passes a convex portion.

When the front wheel 2a rides on a convex portion while the vehicle is running, the vehicle body l assumes a forward upward position (left side portion of Fig. 18(a)). At this time, the pitch rate (pitch angular velocity) θ and the pitch angular acceleration θ are as shown in FIGS. 18(b) and (C).

Then, along with this pitching motion, the longitudinal acceleration sensor 14 swings around the pitching center, and even if the vehicle is traveling at a constant speed, α2 sentences, θ...
(1) Sentence: The longitudinal acceleration αX (apparent acceleration) indicated by the distance between the pitching center and the longitudinal axis speed sensor is detected ((d) in the same figure). Then, the longitudinal acceleration change rate ax obtained based on this apparent acceleration (see figure (e)
)) When the front wheel 2a rides on the convex part, the first
As shown in the Turok diagram in FIG. 6, pressure fluid is supplied to the cylinder 4a on the front wheel 2a side, and is discharged from the cylinder 4b on the rear wheel 2b side. As a result, pitching (upward tilting of the front) becomes even larger.

Furthermore, when the front wheel 2a enters the recess and leans forward, the longitudinal acceleration sensor 14 detects the longitudinal acceleration α8 in the opposite direction to that shown in FIG. This will cause the dog to scream.

Furthermore, the problem of worsening the vehicle body attitude due to apparent acceleration is not limited to the above-mentioned anti-pitch control, but also includes attitude control for so-called low links such as roll and yaw. The same can be said in the case of .

The present invention was made with the aim of solving the above-mentioned problems, and is capable of properly controlling posture without being affected by apparent acceleration associated with pitching motion or low link (roll or yaw) motion caused by road surface conditions. It is an object of the present invention to provide a suspension control device that can perform the following actions.

(Means for solving the problem) In order to achieve the above purpose, first. The second and i$3 inventions include a longitudinal acceleration sensor that detects the longitudinal acceleration acting on the vehicle body, and a control signal that calculates the acceleration change rate from the data detected by the longitudinal acceleration sensor and multiplies it by an arbitrary gain. , a controller that operates a means for supplying and discharging pressurized fluid to cylinders interposed between each of the axles of the front and rear wheels and the vehicle body based on the control signal, In a suspension control device that performs anti-pitch control of a vehicle body by adjusting the amount of pressure fluid supplied and discharged to and from the cylinder by operation, a first aspect of the present invention is an accelerator sensor that detects an operation amount of an accelerator or an operation amount of a flake. A flake sensor is connected to the controller, and when the rate of change of the detected value of the sensor connected to the controller is smaller than a preset threshold, the controller detects an anti-flake sensor based on the data detected by the longitudinal acceleration sensor. The second aspect is to provide arithmetic control means for not performing pitch control.
In the invention, a pitch rate sensor for detecting the pitch rate of the vehicle body is connected to the controller, and the controller includes a differentiation circuit for differentiating a detection signal of the pitch rate sensor to calculate pitch angular acceleration, a calculation control means for not performing anti-pitch control based on data detected by the longitudinal acceleration sensor when acceleration and longitudinal acceleration detected by the longitudinal acceleration sensor are in the same direction; In the invention, a pair of acceleration sensors in the same detection direction connected to the controller are arranged on the vehicle body at a certain distance, and the controller detects the detection signal of one of the pair of acceleration sensors from the detection signal of the other one. A difference is calculated by subtracting the detection signal, and when the acceleration of this difference and the longitudinal acceleration detected by the longitudinal acceleration sensor are in the same direction, anti-pitch control is not performed based on the data detected by the longitudinal acceleration sensor. The present invention is characterized in that it is equipped with arithmetic control means that performs the following operations.

In addition, in order to achieve the above purpose, the fourth. The fifth and sixth inventions provide a lateral acceleration sensor that detects lateral acceleration acting on a vehicle body, and calculate a control signal by calculating an acceleration change rate from data detected by the lateral acceleration sensor and multiplying this by an arbitrary gain. a controller that operates a means for supplying and discharging pressure fluid to a cylinder interposed between an axle and a vehicle body based on the control signal; In a suspension control device that performs anti-roll control of a vehicle body by adjusting the amount of supply and displacement of connect and set up,
The controller includes a storage means for storing vehicle speed data, steering wheel angle, and lateral acceleration data in correspondence with each other, reads lateral acceleration data from the storage means based on the detection data of each sensor, and calculates the absolute value of the lateral acceleration data. A fifth invention further comprises: arithmetic control means for not performing anti-roll control based on the data detected by the longitudinal acceleration sensor when the longitudinal acceleration sensor is smaller than a threshold; A controller is provided with a differential circuit that calculates a late angular acceleration by differentiating the detection signal of the late sensor, and a differential circuit that calculates a late angular acceleration by differentiating the detection signal of the late sensor, and a differential circuit that calculates a late angular acceleration in the same direction as the late angular acceleration detected by the lateral acceleration sensor. A sixth aspect of the present invention further comprises: arithmetic control means for not performing anti-roll control based on data detected by the longitudinal acceleration sensor at a certain time; The sensors are arranged on the vehicle body at a certain distance, and the controller calculates a difference by subtracting the detection signal of one of the pair of acceleration sensors from the detection signal of the other, and calculates the difference between the acceleration of this difference and the The vehicle is characterized by comprising arithmetic control means for not performing anti-roll control based on data detected by the longitudinal acceleration sensor when the lateral acceleration detected by the lateral acceleration sensor is in the same direction. Note that the term "roll" herein refers to rotation in the left-right direction about an axis in the longitudinal direction, that is, a roll motion, and rotation of the vehicle in a horizontal plane, that is, a yaw motion.

(Function) According to the first invention, when the vehicle is configured as described above and is running at a constant speed, even if the vehicle is tilted on an uneven surface, the rate of change of the detection signal of the accelerator sensor or the brake sensor is Accordingly, the arithmetic control means does not perform anti-pitch control based on the rate of change in longitudinal acceleration obtained from the detection signal of the longitudinal acceleration sensor.

Since the second invention is configured as described above, when the vehicle travels on an uneven surface and tilts (makes a bitching motion), the acceleration (apparent acceleration) generated due to this bitching motion is generated.
and the pitch angular acceleration obtained from the data detected by the pitch rate sensor are in the same direction, and when multiplying both data, the sign of the data is positive, and accordingly, the arithmetic control means,
Anti-pitch control is not performed based on the longitudinal acceleration change rate obtained from the detection signal of the longitudinal acceleration sensor.

The third invention is configured as described above, so that when the vehicle travels on an uneven surface and tilts (makes a bitching motion), the acceleration (apparent acceleration) generated due to this bitching motion is detected by an acceleration sensor. The acceleration obtained from the detected data is in the same direction, and the calculation control means accordingly
Anti-pitch control is not performed based on the longitudinal acceleration change rate obtained from the detection signal of the longitudinal acceleration sensor.

Since the fourth invention is configured as described above, when a low link movement is performed while driving at a constant speed without making a large steering wheel operation, the detection signal of the single steering wheel angle sensor and the detection signal of the vehicle speed sensor become small. , and the lateral acceleration data read out using these data is small, and accordingly, the calculation control means does not perform anti-roll (roll or yaw) control based on the lateral acceleration change rate obtained from the detection signal of the lateral acceleration sensor.

Since the fifth invention is configured as described above, when a low link movement occurs while driving at a constant speed without making a large steering wheel operation, an acceleration (apparent The acceleration) and the angular acceleration obtained from the data detected by the late sensor are in the same direction, and accordingly, the calculation control means does not perform anti-roll control based on the lateral acceleration change rate obtained from the detection signal of the lateral acceleration sensor. .

The sixth invention is configured as described above, and when a low link movement occurs while driving at a constant speed without making a large steering wheel operation, an acceleration (apparent) generated due to the low link movement. The acceleration obtained from the data detected by the pair of acceleration sensors is in the same direction, and the sign of the multiplication of both data is positive. Anti-roll control based on the rate of change in lateral acceleration obtained from the signal is not performed.

(Example) The present invention will be explained in detail below.

1 to 3 show a first embodiment. This first embodiment is designed to be used in a vehicle equipped with a clutch, and compared to the conventional example shown in FIGS.
An accelerator sensor 16 for detecting the amount of brake operation, a brake sensor 17 for detecting the flake hydraulic pressure P corresponding to the amount of brake operation, and a vehicle speed sensor 18 for detecting the traveling speed V of the vehicle are each connected to the controller 15. , a differentiation circuit 19 that calculates each change rate (accelerator opening change rate A, brake fluid pressure change rate T, vehicle speed change rate V) by differentiating the detected values of each sensor, and a differentiation circuit 19 that calculates each change rate (accelerator opening change rate A, brake fluid pressure change rate T, vehicle speed change rate V), and and a calculation control means 20 that performs calculation processing and sets 1Xn to zero in the gain described below based on the processing result, and a longitudinal acceleration sensor 14.
The difference is that the signal of the detected longitudinal acceleration α8 is multiplied by Xn to calculate the instantaneous flow rate 9 proportional to the longitudinal acceleration change rate α8. The other constituent members are the same as those shown in the conventional example described above, and are indicated by the same symbols as in the conventional example, and the explanation thereof will be omitted.

The accelerator sensor 16, the brake sensor 17, and the vehicle speed sensor 18 output their detection data to the differentiating circuit 19, and the differentiating circuit 19 calculates the accelerator opening change rate A, the brake fluid pressure change rate p, and the vehicle speed based on the input data. The rate of change V is calculated and outputted to the calculation control means 20.

The arithmetic control means 20 is designed to perform arithmetic processing as shown in FIG. That is, first, when the vehicle speed change rate V is inputted (Stellaf l (hereinafter referred to as Sl)), it is determined whether or not the accelerator opening change value AH is exceeded (S2).

If the amount of accelerator operation is small, a negative determination is made in S2. If it is determined NO in S2, the pressure threshold P,
, h (S3).

If the amount of brake operation is small, S3 will be determined as No. If NO is determined in S3, the vehicle speed change rate V obtained by Sl is subtracted from the current vehicle speed change rate V1 obtained in S6, which will be described later, and the change in vehicle speed is determined by the previously set reference difference vehicle speed change rate ΔV. Determine whether it exceeds (
S4).

If it is determined as No in S4, n of one element of Xn is added to the gain.
is set to zero (S5), the car input as Sl (S6), and the process returns to Sl.

If the driver suddenly operates the accelerator, it will be determined as Yes in Sl, and if it is determined as Yes, the calculation process will be performed in S7 to set the acceleration rate threshold value Vt.
Vehicle speed change rate threshold value vt to determine whether the vehicle speed change rate exceeds h
The fact that it exceeds h indicates that there is a possibility that the accelerator is being operated and that the true acceleration is working.
If it is determined Yes in S7, the n is set to 1 (S8),
Check the longitudinal acceleration change rate. The gain is multiplied by 1, and based on this, the instantaneous flow rate q proportional to the longitudinal acceleration change rate and the current value corresponding thereto are determined so that anti-pitch control can be performed, and the process proceeds to step 86.

Further, if it is determined Yes in S3 or S4, the process advances to 88 to prevent pitching from occurring due to flake or clutch operation. Note that in vehicles equipped with a clutch, pitching occurs not only due to accelerator and brake operations, but also due to clutch operation (ON operation and OFF operation), but this S4 process is applied to vehicle pitching that occurs only due to clutch operation. By performing this, anti-pitch control can be activated.

If the determination is No in S7, the process proceeds to 88 without changing n. Although the determination is made in S7, the reason why the process in step 87 is performed in addition to the previous stage acceleration state determination process is to prevent erroneous determination of accelerator operation when the clutch is OFF. be.

The operation of the suspension control device configured as above will be explained.

First, when the vehicle rides on the front wheel 2a or a convex portion while the vehicle is traveling at a constant speed, the vehicle body l assumes a forward upward position. At this time, data detected by each of the accelerator sensor 16, flake sensor 17, and vehicle speed sensor 18 is input to the differentiation circuit 19. Then, the differentiating circuit 19 calculates the rate of change, and the obtained data is read into the arithmetic control means 20. The arithmetic control means 20 performs the above-described processing on this read data. In this case, while driving at a constant speed, the front wheel 2a just ran over the convex part, so the accelerator operation did not significantly increase, so S2 judged No, and the sudden brake operation However, since the front wheel 2a ran onto the convex portion, the vehicle V1 did not exceed the standard differential vehicle speed change rate ΔV, so S4 was determined to be No. For the gain, n of one element of Xfi is set to zero (S5). As a result, at this stage, pitching (upward tilting of the front), which occurs in the conventional example, can be prevented from worsening, and ride comfort will not be deteriorated.

Also, when the front wheel 2a enters the recess and leans forward while driving at a constant speed, S2, S3. S4
The result is No, and in the end, one element of Xn, n, is set to zero in the gain to prevent pitching (leaning forward).

In addition, if the accelerator is operated greatly or the brake pedal is operated greatly while driving, the calculation control means 20
is determined to be Yes in S2, or determined to be Yes in S3, and the above n is set to 1. Then, a control signal is generated by multiplying the longitudinal acceleration change rate α8 by a gain of 1, and anti-pitch control is performed based on this control signal to prevent pitching from occurring.

Also, if you are driving without operating the accelerator or brake pedal too much (in this state, S2 and S3 will be determined as No), and the clutch is turned ON and the vehicle speed increases, It is determined Yes in step S4, and as a result, n is set to 1 and anti-pitching control is activated, thereby preventing the occurrence of squat.

Furthermore, when the accelerator is depressed with the clutch OFF, a YES determination is made in S2 and the process proceeds to 87, but a NO determination is made in S7 and n is not changed at this stage. . Clutch O like this
When the accelerator is operated during FF, anti-pitching control is not applied to avoid control errors.

In this embodiment, the vehicle speed sensor 18 is provided, but the present invention is not limited to this, and the vehicle speed sensor 8 may be omitted when used in a vehicle without a clutch. In addition, although this embodiment uses an example in which an accelerator sensor 16 and a brake sensor 17 are provided, the present invention is not limited to this. If the object is to be prevented, only one of the accelerator sensor 16 or the brake sensor 17 may be provided depending on the object to be prevented.

Next, a second embodiment will be described with reference to FIGS. 4 and 5. This $2 embodiment is provided with a pitch rate sensor 21 for detecting the pitch rate θ of the vehicle body l in place of the ratio acceleration sensor 16, brake sensor 17, and vehicle speed sensor 18 in the first embodiment described above, and The controller 15 outputs 1 to the gain multiplied by the differential circuit 22 which calculates the pitch angular acceleration by differentiating the detection signal of the pitch rate sensor 21, and the signal of the longitudinal acceleration α detected by the longitudinal acceleration sensor 14. The acceleration θ and the longitudinal acceleration α detected by the longitudinal acceleration sensor 14. The difference is that, when the sign of the data obtained by multiplying and calculating is positive, the gain is set to zero. The other constituent members are the same as those shown in the first embodiment described above, and are indicated by the same symbols as in the first embodiment.
The explanation will be omitted.

The pitch rate sensor 21 outputs the detected pitch rate θ to the differentiating circuit 22, which differentiates the input data to calculate the pitch angular acceleration θ, and outputs this to the arithmetic control means 23.

As shown in FIG. 3, the arithmetic control means 23 multiplies the signal of the longitudinal acceleration α8 detected by the longitudinal acceleration sensor 14 by the pitch angular acceleration θ, and calculates the multiplication data θ・α8 and calculates the sign of the signal. If the gain is negative, 1 is set to zero, and if the gain is negative, the value 1 ((k#0) is output.

The operation of the suspension control device configured as described above will be explained with reference to FIG. 6 and FIG. In addition, in order to make the data correspond, (a), (b), (c),
(d) and (e) are those in Figure 18 mentioned above, and those in Figure 7.
Figures (a) and (b) are transcriptions of those in Figure 17.

If the vehicle is traveling at a constant speed and runs over the front wheel 2a or a convex part, the vehicle body l will tilt forward as shown in the left side of Fig. 6(a) (as mentioned above, the pitching of the lower pitch is considered to be positive). become). Then, the pitch rate sensor 21 detects the pitch rate θ, and the differentiating circuit 22 differentiates the pitch rate θ to calculate the pinch angular acceleration J (FIG. 2(a)).

(b), (c)). At this time, the longitudinal acceleration sensor 1
4, along with the inclination (rotation) of the vehicle body l, a longitudinal acceleration αX (apparent acceleration) as shown in the same figure (d) acts and is detected, and this longitudinal acceleration α8 is shown in the same figure (c). The waveforms have the same direction with respect to the pitch angular acceleration θ.
The arithmetic control means 23 multiplies the pitch angular acceleration θ and the longitudinal acceleration α8 shown in FIG. Determine whether the sign is positive or negative. At this time, the pitch angular acceleration θ and the longitudinal acceleration α8 are in the same direction, so their signs are positive. Then, the gain will be set to zero and output. As a result, even if a wheel runs onto a convex part of the road surface and the vehicle body l leans forward, pitching (front heeling) will not be exacerbated.

Further, when the vehicle is traveling at a constant speed and the front wheels 2a enter a recess, the vehicle body l leans forward. In this case as well, since the longitudinal acceleration αX (apparent acceleration) acting on the longitudinal acceleration sensor 14 and the pitch angle acceleration θ are in the same direction, the arithmetic control means 23 adjusts the gain as in the case of the front roll described above. It will be output as zero. As a result, it is possible to avoid a situation that promotes pitching (leaning forward).

Furthermore, when the brakes are operated greatly while driving, a longitudinal acceleration α in the deceleration direction is applied to the vehicle body l as shown in Fig. 7, and the direction of the pitch angular acceleration θ and the direction of the longitudinal acceleration α8 are different at the initial stage of operation. No match (Figure 7(e)
, (b)), Therefore, the multiplication data becomes negative, and the arithmetic control means 23 outputs the gain k. As a result, anti-pitching control is activated to prevent dives from occurring. Furthermore, even if the accelerator is operated greatly while driving, the same effect will be applied to prevent the occurrence of a squat.

Next, an embodiment of the invention of claim 3 (referred to as a third embodiment)
will be explained with reference to FIGS. 8 to 10. This third
Compared to the second embodiment described above, this embodiment uses a pair of vertical acceleration sensors 24a and 24 arranged at the front and rear sides of the vehicle body l in place of the pitch rate sensor 21 of the second embodiment.
b is provided, and the controller 15 calculates a difference by subtracting the detection signal of the front vertical acceleration sensor 24a from the detection signal of the rear vertical acceleration sensor 24b, and the difference is calculated by subtracting the detection signal of the front vertical acceleration sensor 24a from the detection signal of the rear vertical acceleration sensor 24b. The difference is that the gain is provided with an arithmetic control means 25 which sets 1 to zero when the sign of the data obtained by multiplying by the longitudinal acceleration α8 is correct. The other constituent members are the same as those shown in the second embodiment described above, and are designated by the same reference numerals as in the second embodiment, and the explanation thereof will be omitted.

The front and rear vertical acceleration sensors 24a and 24b measure the vertical acceleration α', α,
is detected and outputted to the calculation control means 25. The calculation control means 25 calculates the difference (α1−α,) by subtracting the vertical acceleration α on the front side from the vertical acceleration α on the rear side, and calculates the difference (α1−α,).

αf) is used instead of the pitch rate change rate θ of the second embodiment, and the difference (α, -αf) is multiplied by the detection signal of the longitudinal acceleration sensor 14α in the same manner as in the second embodiment, The multiplication is done by determining whether the calculation data (α, α,)・α is positive or negative, and if it is positive, the gain is set to zero.

The operation of the suspension control device configured as described above will be explained with reference to FIG. 10.

When the vehicle is traveling at a constant speed and the front wheel 2a rides on a convex portion, the vehicle body 1 will move as shown in Figs. 10(a), (b), (c).
), the pitching motion (front rolling motion) occurs, and as a result of this motion, the front and rear sides of the vehicle body l undergo vertical acceleration αf (upward direction is positive) as shown in (e) of the same figure. )
and the vertical acceleration α of the rear side. The front and rear vertical acceleration sensors 24a and 24b measure the front and rear vertical acceleration αf.

α, is detected and outputted to the arithmetic control means 25. The calculation control means 25 calculates the difference (α, αf) by subtracting the front vertical acceleration α from the rear vertical acceleration α, and calculates the difference (α, αf) between the longitudinal acceleration α8 detected by the longitudinal acceleration sensor 14 and this difference (α1−α , ) to calculate the multiplication data (α, -αf)・
Calculate αX and determine whether its sign is positive or negative.

At this time, since the difference (α, -αf) and the detection signal α of the longitudinal acceleration sensor 14 are in the same direction, the multiplication is calculated data (α, -αf)・α8 is shown in (f) in the same figure. It is positive as shown.

Then, the arithmetic control means 25 outputs the gain as zero. As a result, even if the front wheel 2a rides on a convex portion of the road surface and the vehicle body l tilts forward upward, pitching (front upward leaning) will not be exacerbated.

Also, in this third embodiment, when the front wheel 2a or four parts enter the front wheel 2a, or when the handlebar or the brakes are operated greatly, the same effect as explained in the second embodiment occurs, and pitching (forward tilting) occurs. and prevent the occurrence of pitching. Note that this detailed description will be omitted.

In the embodiment of Sui-Tei 3, a pair of vertical acceleration sensors 24a and 24b are arranged on the front and rear sides of the car body l, and these are connected to the controller 15. A longitudinal acceleration sensor may be arranged and connected to the controller 15.

Next, embodiment 4.5.6 will be described. Section 4.5.6
In contrast to the embodiment 1.2.3 which performs anti-pitching control, the embodiment performs anti-roll control, and the lateral acceleration α7 acting on the vehicle body l is From the lateral acceleration sensor 26 to be detected and the data detected by the lateral acceleration sensor 26, the lateral acceleration change rate is determined.
Calculate the control signal by multiplying this by an arbitrary gain,
It has a controller 27 that operates pressure fluid supply/discharge means (not shown) to cylinders interposed between the left and right wheel axles (not shown) and the vehicle body 1 based on this control signal. What I did was very different. Also,
Left and right vehicle height sensors 28a.

28b is provided between the vehicle body l and the axles of the left and right wheels, and left and right proportional flow control valves 29a and 29b are provided corresponding to the left and right wheels, respectively. Further, the lateral acceleration sensor 26 detects as a positive value when a lateral acceleration α7 in the left direction acts on the vehicle body l, and upon detection of the lateral acceleration α7 in this direction, pressure fluid is applied to the left and right cylinders respectively. It is designed to supply and discharge water. In addition, Section 4.5
．． Embodiment 6 has a relationship corresponding to Embodiment 1.2.3, respectively, and will be described below with reference to Embodiment 1.2.3.

The fourth embodiment includes the accelerator sensor 16 of the first embodiment,
In place of the torque sensor 17, a steering wheel angle sensor 30 for detecting the amount of operation of the steering wheel is provided as shown in FIG.
The controller 27 receives vehicle speed V data and steering wheel angle θ7.
data and lateral acceleration αY.

The data of the lateral acceleration αY is read out from the storage means 31 based on the detection data of each of the sensors, and the absolute value of the lateral acceleration αn is smaller than the threshold value αyth. , to the gain, xH
calculation control means 32 for setting n to zero.

In this case, the lateral acceleration sensor 26 detects the leftward lateral acceleration α7 acting on the vehicle body l as a positive value, and by detecting the lateral acceleration αY in the parentheses, pressure is applied to the left and right cylinders, respectively. It is designed to supply and discharge fluid.

The data stored in the storage means 31 is such that the roll angle during rotation of the vehicle is proportional to the lateral acceleration α7 generated on the vehicle body l,
In the range of lateral acceleration α7 or lower, it is proportional to the square of the vehicle speed and proportional to the amount of steering (steering wheel angle).
16411), and this is shown in a diagram as shown in FIG. 12.

The arithmetic control means 32 specifies the steering wheel angle θh and the vehicle speed V to the storage means 31, reads out the data of the lateral acceleration α7°, and records the rate of change mi7. seek. This lateral acceleration change rate α7. It is necessary to judge whether the magnitude l=Y, 1 is larger than the lateral acceleration threshold αyth.
O), if the determination is Yes, set n to 1, which is one element of
2).

The operation of the suspension control device according to the fourth aspect of the invention configured as described above will be explained.

When the vehicle is running, the data of the lateral acceleration αY1 in the storage means 31 is input to the calculation control means 32 according to the designation of the data detected by the steering wheel angle sensor 30 and the vehicle speed sensor 18, respectively. Then, the arithmetic control means 32 performs the above-described SIO determination process based on the input data. If the vehicle body leans to the left or right due to road surface conditions without sudden steering operation, the steering wheel angle detected by the steering wheel angle sensor 30 is small, and therefore the arithmetic control means 32 detects a small value of the lateral The acceleration αY is read from the storage means 31, and Sll determines No and outputs n as zero. As a result, promotion of low links is prevented.

Furthermore, if the steering wheel is operated greatly while driving, the arithmetic control means 32 determines Yes in the SIO, sets n to 1, and performs anti-roll control based on the longitudinal acceleration change rate &8. This will prevent the occurrence of links.

Note that in the fourth embodiment, when the SIO determines Yes, n is set to 1, but as shown in FIG. It may be set to a value proportional to XY-.

The fifth embodiment is based on the pitch rate sensor 2 of the second embodiment.
1, a roll rate sensor (not shown) for detecting the roll angular velocity φ of the vehicle body 1 is provided. Further, the controller 27 uses a differentiation circuit (not shown) to differentiate the roll angular velocity φ to obtain the roll angular acceleration φ, and multiplies this roll angular acceleration φ by the lateral acceleration α7 detected by the lateral acceleration sensor 26, and the multiplication is Calculation control means (not shown) calculates the calculation data φ・α7 and determines whether the sign is positive or negative, and if it is positive, the gain is set to zero, and if it is negative, it outputs the value k. ).

This suspension control device uses a roll rate sensor to detect roll angular velocity when the vehicle rolls (leans to the left or right) due to road surface conditions while the vehicle is running at a constant speed without sudden steering wheel operations. φ
The roll angular acceleration φ and the lateral acceleration α7, which are obtained by differentiating the above, point in the same direction. As a result, the arithmetic control means outputs the gain as zero, so rolling is prevented from being promoted.

Furthermore, when the steering wheel is operated while driving, the multiplication data φ・α7 becomes negative, and as a result, the arithmetic control means 32 outputs the gain k and performs anti-roll control based on the lateral acceleration change rate. This will prevent rolling from occurring.

In the sixth embodiment, the front and rear vertical acceleration sensors 24a and 24b of the third embodiment are replaced with vertical acceleration α1. α8
The vertical acceleration sensors on the left and right sides detect the
), and the controller 27 subtracts the vertical acceleration α5 on the left side from the vertical acceleration α7 on the right side to calculate the difference (
α8-αL) is calculated, and the difference (α, -αL) is multiplied by the lateral acceleration α7 detected by the lateral acceleration sensor 26. It is provided with arithmetic control means (not shown) that sets the gain to zero when the gain is correct.

In this suspension control device, when the vehicle is running at a constant speed and there is no sudden steering wheel operation, and roll motion occurs due to road surface conditions, etc., the left and right sides of the vehicle body are subject to vertical acceleration α5 due to this motion. ．． αlI (upward direction is positive) will work. The left and right vertical acceleration sensors detect the vertical accelerations αL and α, and output them to the arithmetic control means. Then, the arithmetic control means calculates the difference (α8−αL) and the multiplication data (α
8-αL)·α8 and determine whether its sign is positive or negative. At this time, the difference (α, -αL) and the lateral acceleration αa detected by the lateral acceleration sensor 26 are in the same direction, and their multiplication is the calculation data (α, -αL)·αa is positive. Then, the arithmetic control means outputs n as zero, thereby preventing further rolling.

Also, if the steering wheel is operated greatly while driving, the multiplication data (α, -αL)・α7 becomes negative, and the lateral acceleration ゛・αL becomes negative.
Anti-roll control based on the rate of change α7 is activated to prevent the occurrence of low links.

In the sixth embodiment, the vertical acceleration sensors are provided on the left and right sides of the vehicle body l, but lateral acceleration sensors may be provided on the upper and lower sides of the vehicle body l instead.

In addition, in the above-mentioned 'IIIJ4 to sixth embodiments, the vehicle body l
Although the case where the object is a so-called roll movement in which the object swings from side to side is taken as an example, the present invention is not limited to this, and can also be applied to a yaw movement. In this case, a yaw rate sensor for detecting the angular velocity of the vehicle body in the direction of yaw movement is provided in place of the roll rate sensor of the fifth embodiment. Furthermore, in accordance with the sixth embodiment, lateral acceleration sensors are provided on the front and rear sides of the vehicle body, or longitudinal acceleration sensors are provided on the left and right sides.

(Effects of the invention) 1. As explained above, when the vehicle is traveling at a constant speed and tilts over an uneven surface, the gain is set to zero and the longitudinal acceleration change rate obtained from the detection signal of the longitudinal acceleration sensor is used. Since anti-pitch control is no longer activated, it has the effect of not encouraging pitching motion.

As explained above, in the fourth, fifth, and sixth inventions, when a low link (roll or yaw) movement occurs while driving at a constant speed without making a large steering wheel operation, the gain is reduced to zero. Since the anti-roll control based on the rate of change in lateral acceleration obtained from the detection signal of the lateral acceleration sensor is not activated, this has the effect of not promoting rolling motion.

[Brief explanation of drawings]

Fig. 1 is a side view schematically showing a suspension control device according to an embodiment of the first invention, Fig. 2 is a block diagram showing a controller of the same device, and Fig. 3 is a calculation processing of the arithmetic control means of the controller. Flowcharts showing the contents, FIGS. 4 to 7 show embodiments of the second invention, and FIGS.
Figure 5 is a block diagram showing the configuration, Figure 5 is a block diagram showing the controller of the device, Figure 6 is a waveform diagram showing the operation to prevent bitching from occurring, and Figure 7 is how to prevent bitching from occurring. FIG. 8 to FIG. 10 show an embodiment of the third invention, FIG. 8 is a block diagram showing its configuration, FIG. 9 is a block diagram showing its controller, and FIG. 11 to 13 show an embodiment of the invention of tjs4, FIG. 11 is a block diagram showing the controller, and FIG. 12 is a memory map showing the contents stored in the storage means. ,
FIG. 13 is a flowchart showing the processing contents of the calculation control means, FIG. 14 is a flowchart showing other processing contents in the controller of FIG. 11, and FIGS. 15 to 17 are examples of conventional suspension control devices. , FIG. 15 is a side view schematically showing its configuration, and FIG. 16 is a diagram showing its controller 22...differentiation circuit, 23...arithmetic control means, 24a, 24b...pitch rate sensor, 25
... Arithmetic control means, 26 ... Lateral acceleration sensor, 27
. . . Controller, 29 . . . Left and right proportional flow rate control valves, 30 . . . Handle angle sensor, 31 . (2 other people) l...car body, 7...supply/exhaust means, lla, llb...
- Front and rear proportional flow control valves, 14... longitudinal acceleration sensor, 15... controller, 16... accelerator sensor, 17... flake sensor, I8... vehicle speed sensor, 19... Differential circuit, 20... calculation control means,
21... Pitch rate sensor, melt 1 Fig. 1 Vehicle body 7 Supply/exhaust - 8 stages 11o, 11b Front side, @itjlno? t; Example flow rate control pestle 14 forward/return pumping degree e unit 15 controller 16 AF node le pinga 17 Brake sensor 19 differential circuit 20 Dust 25 Figure 10 Figure 13 Figure 14 Figure '1 Figure 12 enx v' Figure 15 Figure 16 Whistle 17 Figure, 15 @ Figure 18

Claims (6)

[Claims] (1) A longitudinal acceleration sensor detects the longitudinal acceleration acting on the vehicle body, and the acceleration change rate is calculated from the data detected by the longitudinal acceleration sensor. This is multiplied by an arbitrary gain to calculate a control signal, and based on this control signal, a controller that operates a means for supplying and discharging pressure fluid to a cylinder interposed between each of the axles of the front and rear wheels and the vehicle body, and supplying and discharging pressure fluid to the cylinder by operating the supply and discharge means based on the control signal. In a suspension control device that performs anti-pitch control of a vehicle body by adjusting the amount of supply and displacement of , comprising arithmetic control means for not performing anti-pitch control based on data detected by the longitudinal acceleration sensor when the rate of change of the detected value of the sensor connected to the controller is smaller than a preset threshold. A suspension control device characterized by: (2) A longitudinal acceleration sensor detects the longitudinal acceleration acting on the vehicle body, and the acceleration change rate is calculated from the data detected by the longitudinal acceleration sensor. This is multiplied by an arbitrary gain to calculate a control signal, and based on this control signal, a controller that operates a means for supplying and discharging pressure fluid to a cylinder interposed between each of the axles of the front and rear wheels and the vehicle body, and supplying and discharging pressure fluid to the cylinder by operating the supply and discharge means based on the control signal. In a suspension control device that performs anti-pitch control of a vehicle body by adjusting the amount of supply and displacement of A differentiation circuit that calculates pitch angular acceleration by differentiation, and when this pitch angular acceleration and the longitudinal acceleration detected by the longitudinal acceleration sensor are in the same direction,
A suspension control device comprising: arithmetic control means for not performing anti-pitch control based on data detected by the longitudinal acceleration sensor. (3) A longitudinal acceleration sensor detects the longitudinal acceleration acting on the vehicle body, and the acceleration change rate is calculated from the data detected by the longitudinal acceleration sensor. This is multiplied by an arbitrary gain to calculate a control signal, and based on this control signal, a controller that operates a means for supplying and discharging pressure fluid to a cylinder interposed between each of the axles of the front and rear wheels and the vehicle body, and supplying and discharging pressure fluid to the cylinder by operating the supply and discharge means based on the control signal. In a suspension control device that performs anti-pitch control of a vehicle body by adjusting the amount of supply and displacement of A difference is calculated by subtracting the detection signal of one of the pair of acceleration sensors from the detection signal of the other, and when the acceleration of this difference and the longitudinal acceleration detected by the longitudinal acceleration sensor are in the same direction, the longitudinal acceleration A suspension control device comprising arithmetic control means for not performing anti-pitch control based on data detected by an acceleration sensor. (4) A lateral acceleration sensor that detects the lateral acceleration acting on the vehicle body, and the acceleration change rate from the data detected by the lateral acceleration sensor, which is multiplied by an arbitrary gain to calculate a control signal;
a controller that operates a means for supplying and discharging pressure fluid to a cylinder interposed between an axle and a vehicle body based on the control signal; In a suspension control device that performs anti-roll control of a vehicle body by adjusting the amount of supply and displacement of comprises a storage means for storing vehicle speed data, steering wheel angle, and lateral acceleration data in correspondence; lateral acceleration data is read from the storage means based on the detection data of each sensor; and the absolute value of this lateral acceleration data is a threshold value. A suspension control device comprising: arithmetic control means for not performing anti-roll control based on data detected by the longitudinal acceleration sensor when the longitudinal acceleration sensor is smaller than the above value. (5) A lateral acceleration sensor that detects the lateral acceleration acting on the vehicle body, and the acceleration change rate from the data detected by the lateral acceleration sensor, which is multiplied by an arbitrary gain to calculate a control signal;
a controller that operates a means for supplying and discharging pressure fluid to a cylinder interposed between an axle and a vehicle body based on the control signal; In a suspension control device that performs anti-roll control of a vehicle body by adjusting the amount of supply and displacement of
A differentiation circuit that calculates late angular acceleration by differentiating the detection signal of the late sensor, and when this late angular acceleration and the lateral acceleration detected by the lateral acceleration sensor are in the same direction, the data detected by the longitudinal acceleration sensor 1. A suspension control device comprising: arithmetic control means for disabling anti-roll control. (6) A lateral acceleration sensor that detects the lateral acceleration acting on the vehicle body, and the rate of change in acceleration is calculated from the data detected by the lateral acceleration sensor, and this is multiplied by an arbitrary gain to calculate a control signal;
a controller that operates a means for supplying and discharging pressure fluid to a cylinder interposed between an axle and a vehicle body based on the control signal; In a suspension control device that performs anti-roll control of a vehicle body by adjusting the amount of supply and displacement of A difference is calculated by subtracting the detection signal of one of the pair of acceleration sensors from the detection signal of the other, and when the acceleration of this difference and the lateral acceleration detected by the lateral acceleration sensor are in the same direction, the A suspension control device comprising arithmetic control means for not performing anti-roll control based on data detected by an acceleration sensor.