JP3527764B2 - Vehicle braking 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 vehicle braking system in which when a vehicle behavior such as a spin or a drift-out is abnormal, a braking force is applied to each wheel according to the motion state of the vehicle to restore the vehicle behavior. Regarding the control device.

[0002]

2. Description of the Related Art Conventionally, an apparatus of this type is disclosed in, for example, Japanese Patent Laid-Open No.
As disclosed in Japanese Laid-Open Patent Application No. 257756, the invention is applied to a vehicle braking control device provided with a hydraulic control device that controls supply and discharge of brake fluid to and from a wheel cylinder independently of the operation of a brake pedal. The target slip ratio of the wheel for rebuilding the behavior of the vehicle is determined according to the motion state, and the hydraulic control device is controlled according to the determined target slip ratio to match the slip ratio of the wheel with the target slip ratio. I have to.

[0003]

However, in the above conventional device, the target slip ratio is determined only on the basis of the motion state of the vehicle, and the drive state of the vehicle by the driver's operation of the accelerator pedal is taken into consideration. There is a problem that the driver's will is not reflected at all because it is not done. Further, when the target slip ratio is determined only by the motion state of the vehicle while the wheels are driven by the accelerator pedal operation, the deviation between the determined target slip ratio and the actual wheel slip ratio at the start of control is too large. As a result, the generated braking force may change abruptly, and the actual slip ratio of the wheels may become too large, causing the wheels to become locked (see FIG. 9).

The present invention has been made to solve the above problem, and its object is to smoothly change the braking force by correcting the target slip ratio in consideration of the driving force transmitted to the driving wheels. Another object of the present invention is to provide a vehicle braking control device that reflects the driver's will.

[0005]

In order to achieve the above object, the present invention provides a brake hydraulic pressure control device for controlling the supply and discharge of brake fluid to and from a wheel cylinder that applies a braking force to each wheel of a vehicle, and each of the above. and the actual slip ratio detecting means for detecting the actual slip ratio of the wheel, and the target slip rate calculating means for calculating a target slip ratio of each wheel in accordance with the operating condition and the behavior condition of the vehicle, the front Symbol actual slip ratio detecting means a vehicle brake control equipment and control means for the actual slip rate is detected to control the brake pressure control apparatus as set in the target slip ratio, the vehicle
Force detection means for detecting the drive force transmitted to the drive wheel of the vehicle
And the input speed of the torque converter and the output speed of the transmission
Detect torque converter slip ratio based on number
The slip ratio detecting means and the slip of the torque converter.
Of the driving force transmitted to the detected driving wheel
Estimate the driving force of the drive wheels based on the data representing
The driving force estimating means and the driving force estimating means.
The eye of the drive wheel according to the determined drive force of the drive wheel.
Equipped with target slip ratio correction means for correcting the target slip ratio
The present invention provides a vehicle braking control device characterized by the above.

[0006]

In the present invention constructed as described above, the drive wheels estimated by the drive force estimating means are provided.
The target slip ratio of the drive wheels is corrected according to the driving force of
The control means and the hydraulic control device control the slip ratio of each wheel so as to match the corrected target slip ratio. Therefore, the driving state of the vehicle is considered in the target slip ratio, and the driving state of the vehicle is also considered in the braking force applied to the wheels. As a result, according to the present invention, it becomes possible to control the braking of the wheels in which the intention of the driver is reflected in the braking control of the wheels, and it is possible to control the sudden braking force due to the deviation between the target slip ratio and the actual slip ratio of the wheels. The application can be avoided, and the discontinuity of the braking force at the start of the control and the reduction of the acceleration feeling can be suppressed.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 schematically shows a vehicle braking device according to the embodiment and an electric control device for controlling the same by a block diagram. ing.

The vehicle braking device includes a master cylinder 12 that pumps brake fluid from the first and second ports in response to a depression operation of the brake pedal 11. The first port of the master cylinder 12 has electromagnetic valves 31, 4
When 1 is in the illustrated state, it communicates with the wheel cylinders 32, 42 for the left and right front wheels via both valves 31, 41, respectively. Further, the second port of the master cylinder 12 communicates with the left and right rear wheel wheel cylinders 52 and 62 via the proportional valve 13 and the electromagnetic valves 51 and 61, respectively, when the electromagnetic valves 51 and 61 are in the illustrated state.

Further, this vehicle braking device is provided with a hydraulic pump 1.
4, the pump 14 supplies the oil pumped from the reservoir 15 to the high-pressure oil passage L1. An accumulator 16 that stores high-pressure oil is connected to the high-pressure oil passage L1. Between this high-pressure oil passage L1 and the low-pressure oil passage L2 connected to the reservoir 15,
Brake hydraulic pressure control device 3 for left and right front wheels and left and right rear wheels
0, 40, 50, 60 are connected. The brake hydraulic control device 30 for the left front wheel includes a solenoid valve 3 for increasing pressure in addition to the solenoid valve 31 and the wheel cylinder 32 described above.
3 and an electromagnetic valve 34 for decompression. The electromagnetic valve 33 connects the high pressure oil passage L1 to the wheel cylinder 32 in the illustrated state when the electromagnetic valve 31 is switched from the illustrated state, and shuts off the communication in the state where the electromagnetic valve 31 is switched from the illustrated state. When the electromagnetic valve 31 is switched from the illustrated state, the electromagnetic valve 34 has the wheel cylinder 32 in the switched state from the illustrated state.
To the low-pressure oil passage L2, and connect the
Shut off .

The brake hydraulic control device 40 for the right front wheel is also
In addition to the electromagnetic valve 41 and the wheel cylinder 42 described above, electromagnetic valves 43 and 44 that function similarly to the case of the brake hydraulic pressure control device 30 for the left front wheel are provided. The brake hydraulic control device 50 for the left rear wheel also includes electromagnetic valves 53, 54 that function in the same manner as the brake hydraulic control device 30 for the left front wheel, in addition to the electromagnetic valve 51 and the wheel cylinder 52 described above. . The brake hydraulic pressure control device 60 for the right rear wheel also includes the brake hydraulic pressure control device 3 for the left front wheel in addition to the electromagnetic valve 61 and the wheel cylinder 62 described above.
The electromagnetic valves 63 and 64 that function in the same manner as in the case of 0 are provided. The electromagnetic valves described above are maintained in the illustrated state when not energized, and are switched from the illustrated state by energizing.

Next, an electric control device for controlling these electromagnetic valves will be described. The electric control unit controls the steering angle θh, longitudinal velocity Ux, lateral velocity Uy, longitudinal acceleration Gx,
Lateral acceleration Gy, yaw rate Yr, rotational angular velocities of left and right front wheels and left and right rear wheels ωfl, ωfr, ωrl, ωrr, throttle opening θ
s, engine speed Ne, speed of output shaft of transmission Nt,
A sensor group 71 including a plurality of sensors for detecting the shift position shift of the transmission and the presence / absence Br of operation of the brake pedal is provided. A state quantity calculation unit 72 is connected to the sensor group 71, and the calculation unit 72 outputs signals representing the vehicle motion state amount and the driving state amount detected by the sensors as they are,
Based on these state quantities, the actual steering angles Stafl, S of the left and right front wheels
tafr, vehicle traveling direction speed Us, wheel speeds of left and right front wheels and left and right rear wheels Usfl, Usfr, Usrl, Usrr, left and right front wheels and left and right rear wheels slip angles βfl, βfr, βrl, βrr, center of gravity slip angle βg, road surface A necessary vehicle motion state quantity and road surface state quantity such as the friction coefficient μ are estimated and a signal representing the estimated state quantity is output. Further, the state quantity calculation unit 72 also outputs a signal representing the gear ratio ratio of the transmission corresponding to the shift state based on the detected shift state shift of the transmission.

A target slip ratio calculator 73, a behavior abnormality detector 74 and an actual slip ratio calculator 75 are connected to the state quantity calculator 72. The target slip ratio calculation unit 73
The steering wheel steering angle θh output from the state quantity calculation unit 72,
Longitudinal acceleration Gx, lateral acceleration Gy, throttle opening θs, presence / absence of brake pedal operation Br, left / right front wheel and left / right rear wheel slip angles βfl, βfr, βrl, βrr, center of gravity slip angle βg
Based on the above, the target slip ratios Sfl *, Sfr *, Srl *, and Srr * for the left and right front wheels and the left and right rear wheels that correct the vehicle behavior abnormality and stabilize the vehicle traveling are respectively determined. These target slip rates Sfl *, Sfr *, Srl *, Srr *
The detailed calculation method is not described in detail because it is not directly related to the present invention, but if necessary, the contents of Japanese Patent Laid-Open No. 4-257756 described in the section of the prior art can be referred to. The behavior abnormality detection unit 74 estimates the behavior of the vehicle (overall movement state of the vehicle) based on each detection signal from the state quantity calculation unit 72, and outputs a signal indicating the abnormality when an abnormality occurs in the behavior. To do. The actual slip ratio calculation unit 75 calculates the rotational angular velocities ωfl, ωfr, ωrl, ωrr of the left and right front wheels and the left and right rear wheels from the state amount calculation unit 72, and the wheel speeds Usfl, Usfr, Usrl, Usrr of the left and right front wheels and the left and right rear wheels. And the load radius R of each wheel
Based on the (fixed value)
The actual slip rate Sfl, Sfr, Srl, Srr of each wheel is calculated.

[0013]

[Equation 1] Sfl = (Usfl−R · ωfl) / Usfl Sfr = (Usfr−R · ωfr) / Usfr Srl = (Usrl−R · ωrl) / Usrl Srr = (Usrr−R · ωrr) / Usrr Target slip The signals representing the ratios Sfl *, Sfr *, Srl *, Srr * are output to the target slip ratio correction unit 76, and the signals representing the vehicle behavior abnormality and the actual slip ratios Sfl, Sfr, Sr are also included.
A signal representing l, Srr is output to the slip ratio control unit 77.

The target slip ratio correction unit 76 is a target slip ratio Srl *, S for the rear wheels, which are the driving wheels, according to the driving state of the vehicle.
The rr * is corrected and output to the slip ratio controller 77, and the target slip ratios Sfl * and Sfr * of the front wheels, which are non-driving wheels, are also output.
Is output to the slip ratio control unit 77 as it is. When the slip ratio control unit 77 receives the signal indicating the behavior abnormality, the slip ratio control unit 77 receives the target slip ratios Sfl *, Sfr *, the corrected target slip ratios Srl **, Srr **, and the actual slip ratios Sfl, Sfr, Sr.
Brake hydraulic pressure control device 3 for each wheel based on l and Srr
The actual slip ratios Sfl, Sfr, Srl, Srr of the respective wheels are controlled by controlling the respective electromagnetic valves in 0, 40, 50, 60, and the target slip ratios Sfl *, Sfr * and the corrected target slip ratios Srl **, S
Should be equal to rr **. FIG. 2 shows details of the target slip ratio correction unit 76 and the slip ratio control unit 77 for the left rear wheel, which is the driving wheel.

The target slip ratio correction unit 76 is a rotation speed conversion circuit 10 for calculating the slip ratio of the torque converter.
1 and a slip ratio calculator 102. The rotation speed conversion circuit 101 multiplies the engine rotation speed Ne by the gear ratio ratio, converts the input rotation speed of the torque converter into the output rotation speed of the transmission, and outputs it as the input rotation speed Nin (= ratio.Ne). The slip ratio calculator 102 calculates the slip ratio ΔN of the torque converter based on the input rotation speed Nin and the rotation speed Nt of the output shaft of the transmission to calculate the slip ratio ΔN of the torque converter, and the driving force conversion table circuit 103. Output to.

[0016]

## EQU2 ## .DELTA.N = (Nin-Nt) / Nin The driving force conversion table circuit 103 stores a table storing data representing the relationship between the slip ratio .DELTA.N and the driving force transmitted to the driving wheels (see FIG. 3) and an interpolator. The driving force τ transmitted to the driving wheels (rear wheels) by inputting the slip ratio ΔN is read from the table, and the read driving force τ is interpolated and output to the distribution circuit 104. .
The distribution circuit 104 distributes the driving force τ to the driving force τl for the left rear wheel and the driving force τr for the right rear wheel in accordance with the ratio of the rotational angular velocities ωrl, ωrr of the two rear wheels, and for the left rear wheel. The driving force τl is output to the multiplier 105. The driving force τr for the right rear wheel is supplied to the target slip ratio correction unit and the slip ratio control unit (not shown) for the right rear wheel. The multiplier 105 multiplies the driving force τl for the left rear wheel by a coefficient K and supplies the result to the subtractor 106.
The subtracter 106 calculates the actual driving force Ftrc * for the left rear wheel by subtracting the loss Δτ due to the wheel rotation moment calculated by the loss calculator 107 from the driving force τl multiplied by the coefficient K. The loss calculator 107 inputs the rotational angular velocity ωrl of the left rear wheel, and uses the rotational angular velocity ωrl and the tire rotational inertia moment I and the dynamic load radius R of the tire as a constant, The loss Δτ is calculated by executing the calculation, and a signal representing the loss Δτ is output to the subtractor 106.

[0017]

## EQU3 ## Δτ = (I / R) dωrl / dt The signal representing the driving force Ftrc * of the left rear wheel from the subtractor 106 is supplied to the adder 108, and the adder 108 has a braking target value. The arithmetic unit 109 is connected. The braking target value calculator 109 calculates the target slip ratio S *, the road surface friction coefficient μ,
By inputting signals representing the slip angle βrl of the left rear wheel and the tire ground contact load Fz (treated as a constant in this case), the braking force target Fbrk * for obtaining the target slip ratio S * for the left rear wheel is set. The variables S *, μ · Fz, βr as shown in FIG. 4 are determined in the form of an arithmetic unit and a four-dimensional map.
A table showing the relationship between l and Fbrk * is provided. The braking target value calculator 109 calculates a product value μ · Fz of the road surface friction coefficient μ and the tire ground load Fz, and the calculated product value μ ·
The braking force target Fbrk * is derived by referring to the table based on Fz, the target slip ratio S * and the slip angle βrl, and the derived braking force target Fbrk * is interpolated to obtain the final braking force target Fbrk *. To decide. Although the braking force target Fbrk * is determined using the table in the present embodiment, the braking force target Fbrk * is calculated by the neural network calculation that inputs the variables S *, μ · Fzμ, βrl.
You may make it determine k *.

The adder 108 is the driving force Ftr for the left rear wheel.
c * and braking force target Fbrk * are added, and the same addition result Ftrc *
+ Fbrk * is output to the target slip ratio calculator 110 as the corrected braking force Fx * for the left rear wheel. The target slip calculator 110 is also composed of a calculator and a table showing the relationship among the variables S **, μ · Fz, βrl, and Fx * as shown in FIG. 4 in the form of a four-dimensional map. The corrected target slip ratio S ** is derived by calculating the multiplied value μ · Fz of the ground contact load Fz and referring to the table based on the calculated multiplied value μ · Fz, the corrected braking force Fx * and the slip angle βrl. At the same time, the correction target slip ratio S ** is interpolated to determine the final correction target slip ratio S **. Also in this case, the correction target slip ratio S ** is calculated by the neural network calculation in which the variables Fx *, μ · Fzμ, and βrl are input.
May be determined.

The slip ratio controller 77 includes a subtractor 121 for calculating a deviation S **-S between the corrected target slip S ** and the actual slip ratio S. The output of the subtractor 121 is connected to a differential control term calculator 122, a proportional control term calculator 123, and an integral control term calculator 124, which are connected in parallel. Each of the computing units 122, 123, and 124 realizes a known PID (proportional, derivative, integral) feedback control, and executes the computation of the following equation 4 to generate signals representing the computation results CALd, CALp, CALi. Output.

[0020]

[Equation 4] CALd = Kd · d (S ** − S) / dt CALp = Kp · (S ** − S) CALi = Ki · ∫ (S ** − S) dt The coefficient in the above Equation 4 Kd, Kp, Ki are predetermined constants.

The signals representing the calculation results CALd, CALp, CALi of the respective calculation units 122, 123, 124 are supplied to the adder 125, which in turn calculates these calculation results CALd, CALp, CA.
Li is added and the addition result is fed back to the feedback control signal Cfb.
To the interval time converter 126. The interval time converter 126 has a table of characteristics as shown in FIG. 5, and converts the feedback control signal Cfb into an interval signal Tfb representing a pulse cycle (time interval) and outputs it to the pulse generator 127. Pulse generator 1
Reference numeral 27 includes a counter, a comparator, a one-shot circuit, etc., and outputs a control pulse signal P having a constant pulse width at each time interval represented by the interval signal Tfb. The pulse generator 127 will be further described. As shown in FIG. 6, if the interval signal Tfb is positive,
When the counter measures the time represented by the signal Tfb, the comparator and the one-shot circuit output a positive control pulse signal having a constant width. Also, the interval signal T
When fb is negative, when the counter measures the time represented by the absolute value | Tfb | of the signal Tfb, the comparator and the one-shot circuit output a negative pulse signal having a constant width. Therefore, the slip ratio control unit 77 has an interval that is inversely proportional to the absolute value | S **-S | of the deviation S **-S between the corrected target slip ratio S ** and the actual slip ratio S, and the deviation S **
The control pulse signal P for feedback with a positive and negative constant width corresponding to the positive and negative signs of -S is output to the drive circuit 128.

The drive circuit 128 operates when a signal indicating the behavior abnormality of the vehicle arrives from the behavior abnormality detection unit 74 to energize the electromagnetic valve 51. In this energized state, the electromagnetic valve 53 responds to the control pulse signal P. , 54 is energized and de-energized. If the control pulse signal P does not arrive in the energized state of the electromagnetic valve 51, the electromagnetic valve 53 is energized to switch the valve 53 from the illustrated state, and the electromagnetic valve 5
De-energize No. 4 to keep the valve 54 in the illustrated state. When the positive control pulse signal P arrives, the electromagnetic valves 53 and 54 are de-energized to keep the valves 53 and 54 in the illustrated state. When the negative control pulse signal P arrives, both electromagnetic valves 53, 54 are energized to turn on both valves 53, 54.
54 is switched from the illustrated state. If the signal indicating the behavior abnormality does not arrive, all the electromagnetic valves 51, 53, 54
Then, all the valves 51, 53 and 54 are maintained in the illustrated state by de-energizing.

The target slip ratio correction unit and the slip ratio control unit for the right rear wheel, which is the driving wheel, are also included in the target slip ratio correction unit 76 and the slip ratio control unit 77 except for the rotation speed conversion circuit 101 to the distribution circuit 104 described above. The target slip ratio correction unit for the left and right front wheels, which is configured in the same manner as the above, outputs the target slip ratio S * determined by the target slip ratio calculation unit 73 to the slip ratio control unit 77 as it is.

Next, the operation of the embodiment configured as described above will be described. Brake pedal 1 while the driver is driving the vehicle
When the user depresses 1, brake fluid is discharged from the first and second ports of the master cylinder 12. If the behavior of the vehicle is normal and the signal indicating the behavior abnormality is not output, all the electromagnetic valves are in the illustrated state. Therefore, in this case, the brake fluid from the first port passes through the electromagnetic valves 31, 41 and the wheel cylinders 32, 42.
And the brake fluid from the second port is supplied to the proportional valve 14 and the electromagnetic valves 51, 62.
Is supplied to the wheel cylinders 52 and 62 via. As a result, in this case, the braking force according to the depression operation of the brake pedal 11 is applied to each wheel, and the vehicle is braked.

On the other hand, when a behavior abnormality occurs in the vehicle, the behavior abnormality detection unit 74 detects the abnormality and detects the slip ratio control unit 7
A signal indicating abnormal behavior is output to 7. In the slip ratio control unit 77, the drive circuit 128 energizes the electromagnetic valves 31, 41, 51, 61 in response to the signal indicating the behavior abnormality. Thereby, the electromagnetic valves 31, 41, 51, 6
1, the brake oil supply path from the master cylinder 12 to the wheel cylinders 32, 42, 52, 62 is closed and the cylinders 32, 4 are closed.
The supply and discharge of the brake fluid to 2, 52, 62 are under the control of electromagnetic valves 33, 34, 43, 44, 53, 54, 63, 64.

On the other hand, the target slip ratio calculating unit 73 calculates the target slip ratio S * according to the motion state of the vehicle and outputs a signal representing the target slip ratio S * to the target slip ratio correcting unit 76.
Supply to. In the target slip ratio correction unit 76, the target slip ratio S * is converted into the braking force target Fbrk * by the braking target value calculator 109. At the same time, the rotation speed conversion circuit 101, the slip ratio calculator 102, the driving force conversion table circuit 103, the distribution circuit 104, etc. calculate the driving force Ftrc * of the left rear wheel, and the addition operation of the adder 108
The braking force target Fbrk * corresponding to the target slip ratio S * is corrected according to the driving force Ftrc * of the left rear wheel. Then, this corrected braking force Fx * is converted into the corrected target slip rate S ** by the target slip ratio calculator 110. As a result, the target slip ratio S * is corrected according to the driving force Ftrc * of the left rear wheel caused by the accelerator pedal operation, and is output as the corrected target slip ratio S **.

In the slip ratio control unit 77, the subtractor 121 calculates a deviation S **-S between the corrected target slip ratio S ** and the actual slip ratio S from the actual slip ratio calculation unit 75, and differential control is performed. Term calculator 122, proportional control term calculator 123
The integral control term calculator 124, the adder 125, the interval time converter 126, and the pulse generator 128 output the control pulse signal P corresponding to the deviation S **-S to the drive circuit 128.
Output to. In this case, if the deviation S **-S is positive, the control pulse signal P is a signal composed of a plurality of positive pulses with a constant width, and the intern time (cycle) of the pulse is the deviation S **-S. It becomes shorter as the absolute value | S **-S | becomes larger. The drive circuit 128 causes the electromagnetic valve 53, when the control pulse signal P including the positive pulse is generated.
54 is set to the illustrated state, and when the same positive pulse is not generated, the electromagnetic valve 53 is switched from the illustrated state and the electromagnetic valve 54 is set to the illustrated state. Therefore, the brake hydraulic pressure in the wheel cylinder 52 is the absolute value | S *. * -The speed rises in proportion to S |. On the other hand, if the deviation S **-S is negative, the control pulse signal P is a signal composed of a plurality of negative pulses having a constant width, and the intern time (cycle) of the pulse is the deviation S **-S. It becomes shorter as the absolute value | S **-S | becomes larger. The drive circuit 128 switches both the electromagnetic valves 53 and 54 from the illustrated state when the control pulse signal P including the negative pulse is generated, and switches the electromagnetic valve 53 from the illustrated state when the negative pulse is not generated and the electromagnetic valve 54. Is set in the illustrated state, the brake hydraulic pressure in the wheel cylinder 52 drops at a speed proportional to the absolute value | S **-S |. Therefore, the slip ratio of the left front wheel is controlled toward the corrected target slip ratio S ** and converges to the same slip ratio S **.

The right rear wheel also operates as described above, and the slip ratio of the right rear wheel is also the corrected target slip ratio S.
It is controlled toward ** and converges to the same slip ratio S **.
Further, since the target slip ratio S * of the left and right front wheels is not corrected according to the driving force, the slip ratio of the left and right front wheels is controlled toward the uncorrected target slip ratio S * and converges to the same slip ratio S *.

As can be understood from the above description of the operation, according to the above-described embodiment, the target slip ratio S * regarding the driving wheels determined according to the motion state of the vehicle depends on the driving amount related to the depression operation of the accelerator pedal. Is corrected and the driving wheels are controlled so as to match the corrected target slip ratio **, so that the braking control of the wheels that reflects the driver's intention is possible. In addition, as a result of considering the driving state of the wheels in the corrected target slip ratio S **, the change of the actual slip ratio S at the start of the braking control becomes smooth, and the discontinuity of the braking force and the reduction of the feeling of acceleration are reduced. It can be suppressed (see FIG. 8).

Next, a modification of the target slip ratio correction unit 76 of the above embodiment will be described with reference to FIG. In this modified example, a correction amount calculator 131 and an adder 132 are provided instead of the adder 108, the braking target value calculator 109 and the target slip ratio calculator 110 of the above embodiment.

The correction amount calculator 131, like the target slip ratio calculator 110 of the above embodiment, is a slip ratio correction component corresponding to the driving force Ftrc * as shown in FIG. 4 in the form of a calculator and a four-dimensional map. ΔS *, road friction coefficient μ multiplied by tire ground contact load Fz μ · Fzμ, slip angle βrl and driving force Ft
Comprising a table showing the relationship of rc *, calculating the multiplication value μ · Fz of the road surface friction coefficient μ and the tire ground contact load Fz, and a table based on the calculated multiplication value μ · Fz, driving force Ftrc * and slip angle βrl The slip ratio correction amount ΔS * is derived by referring to
Is interpolated and output. In this case also, each variable F
The slip ratio correction amount ΔS * may be determined by a neural network operation that inputs trc *, μ · Fz, and βrl. The slip ratio correction amount ΔS * calculated by the correction amount calculator 131 is added to the target slip ratio S * by the adder 132, and the addition result S * + ΔS * is used as the corrected target slip ratio S **. It is output to the slip ratio control unit 77 similar to the example.

Also in the modified example configured as above, the target slip ratio S * for the drive wheels, which is determined according to the motion state of the vehicle, is corrected according to the drive amount related to the depression operation of the accelerator pedal, and the same drive is performed. Since the wheels are controlled so as to match the corrected target slip ratio S **, the same effect as that of the above embodiment is expected (see FIG. 8).

In the above-mentioned embodiment and modification,
Although the vehicle in which the front wheels are the non-driving wheels and the rear wheels are the driving wheels has been described, the present invention is also applicable to a vehicle in which the front wheels are the driving wheels and the rear wheels are the non-driving wheels, or all the wheels are the driving wheels. . In this case, whichever drive wheel is
Target slip ratio S of the drive wheels determined according to the driving state
* May be corrected according to the drive amount Ftrc * for the drive wheels.

Further, in the above-mentioned embodiment and modification,
Each circuit of the state quantity calculation unit 72, the target slip ratio calculation unit 73, the behavior abnormality detection unit 74, the actual slip ratio calculation unit 75, the target slip ratio correction unit 76, and the slip ratio control unit 77 is configured by a hard circuit. However, each of these circuits can properly realize the same function by software processing such as a microcomputer.

[Brief description of drawings]

FIG. 1 is a diagram schematically showing a vehicle braking device and an electric control device for the same according to an embodiment of the present invention.

FIG. 2 is a block diagram showing in detail a target slip ratio correction unit and a slip ratio control unit of FIG.

FIG. 3 is a graph showing a relationship between a slip ratio and a driving force transmitted to driving wheels in a torque converter.

[Fig. 4] Product of friction coefficient µ of road surface and ground load Fz µF
z, slip ratio S (or corrected slip ratio S **, slip ratio correction amount ΔS *), slip angle βrl, and braking force target Fbrk
4 is a graph showing a relationship with * (or braking force Fx *, driving force Ftrc *).

FIG. 5 is a graph showing a relationship between a feedback control signal Cfb and an interval time Tfb.

FIG. 6 is a time chart for explaining the operation of the pulse converter of FIG.

FIG. 7 is a block diagram showing in detail a target slip ratio correction unit and a slip ratio control unit according to a modified example of the above embodiment.

FIG. 8 is a time chart showing changes in the actual slip ratio, the corrected target slip ratio, and the like according to the present invention.

FIG. 9 is a time chart showing changes in an actual slip ratio, a target slip, etc. by a conventional device.

[Explanation of symbols]

11 ... Brake pedal, 12 ... Master cylinder, 14 ...
Hydraulic pump, 30, 40, 50, 60 ... Brake hydraulic pressure control device for each wheel (hydraulic control device), 32, 42, 52,
62 ... Wheel cylinder, 71 ... Sensor group (target slip ratio determining means, driving force detecting means), 72 ... State quantity calculating section (target slip ratio determining means, driving force detecting means), 73 ...
Target slip ratio calculation unit (target slip ratio determination means), 7
4 ... Behavior abnormality detection unit, 75 ... Actual slip ratio calculation unit, 76
... target slip ratio correction unit, 77 ... slip ratio control unit (control means), 101 ... rotational speed converter (driving force detection means),
102 ... Slip rate calculator (driving force detection means), 103
... Driving force conversion table circuit (driving force detecting means), 108
... Adder (correction means), 109 ... Braking target value calculator (correction means), 110 ... Target slip ratio calculator (correction means), 121 ... Subtractor, 131 ... Correction amount calculator (correction means), 132 ... Adder (correction means).

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Noriaki Hattori 2-1, Asahi-cho, Kariya city, Aichi Prefecture Aisin Seiki Co., Ltd. (72) Kenji Totsu 2-1-1, Asahi-cho, Kariya city, Aichi prefecture Aisin In Seiki Co., Ltd. (72) Inventor Jun Mihara 2-1-1 Asahi-cho, Kariya City, Aichi Prefecture Aisin Seiki Co., Ltd. (72) In-house Takayuki Ito 2-1-1 Asahi-cho, Kariya City, Aichi Aisin Seiki Co., Ltd. (72) Inventor Shingo Sugiura 2-1-1 Asahi-cho, Kariya city, Aichi prefecture, Aisin Seiki Co., Ltd. (72) Inventor Norio Yamazaki 2-1-1, Asahi-cho, Kariya city, Aichi prefecture (56) Reference Documents JP-A-3-227763 (JP, A) JP-A-2-237827 (JP, A) JP-A-3-186465 (JP, A) (58) Fields investigated (Int.Cl . ⁷ , DB name) B60T 8/66 B60T 8/58

Claims (2)

(57) [Claims] 1. A brake hydraulic control device for controlling supply and discharge of brake fluid to and from a wheel cylinder for applying a braking force to each wheel of a vehicle, an actual slip ratio detecting means for detecting an actual slip ratio of each wheel, and a vehicle a target slip rate calculating means for in response to the operating state and behavior state calculates a target slip ratio of each wheel, so that the actual slip ratio detected by the pre-Symbol actual slip ratio detecting means is set to said target slip ratio wherein a vehicle brake control equipment and control means for controlling the brake hydraulic pressure control apparatus, the driving force for detecting a driving force transmitted to the drive wheels of the vehicle
The detection means, the input speed of the torque converter and the output speed of the transmission
Based on the slip rate detecting torque converter slip ratio based on
Up ratio detecting means, the slip ratio of the torque converter, and the detected drive ratio.
Based on the data representing the relationship of the driving force transmitted to the driving wheels
A driving force estimating means for estimating a driving force of the driving wheel, the driving of the driving wheels estimated by the drive force estimating means
An eye that corrects the target slip ratio of the drive wheels according to the force.
A vehicle braking control device comprising a target slip ratio correction means . 2. The drive force estimating means detects the slip ratio of the torque converter and the detected drive force.
Stored data representing the relationship of the driving force transmitted to the driving wheels
A driving force conversion table circuit including a table and an interpolator, and an interpolation calculation by reading from the table and the interpolator
Depending on the ratio of the rotational angular velocities of the left and right drive wheels,
A distribution circuit for distributing and outputting to each drive wheel, and one of the drive wheels provided from the distribution circuit
Multiplier for multiplying the distributed driving force by a predetermined coefficient
And input the rotational angular velocity of one of the drive wheels.
Y Based on the rotational moment of inertia and the dynamic load radius of the tire
Loss calculation to calculate the loss due to wheel rotation moment
A calculator and the loss calculation from the driving force calculated by the multiplier
And a subtractor for subtracting the loss component calculated by the controller, and the actual driving force of one of the drive wheels is subtracted from the subtractor.
The vehicle according to claim 1, wherein the estimated value is calculated.
Dual-purpose braking control device.