JP2644143B2 - Brake 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 brake control device for controlling the running stability and braking state of a vehicle body by increasing or decreasing a brake pressure according to the running state of the vehicle body. The present invention relates to a brake control device that obtains a pressure increase / decrease amount of a brake pressure from a table based on a wheel acceleration / deceleration and a slip rate, and controls a vehicle body.

[0002]

2. Description of the Related Art For example, in an automobile or a motorcycle,
A brake control device is used to control the brake.

This brake control device calculates and calculates a slip ratio between a wheel and a road surface from a vehicle body speed and a wheel speed during traveling, calculates a wheel acceleration / deceleration from the wheel speed, and calculates the wheel acceleration / deceleration and the slip ratio. , A brake pressure increase / decrease amount is obtained from a value preset in the table, and the brake pressure is controlled based on this.

[0004]

However, in such a table as described above, the intervals between the wheel acceleration / deceleration and the slip rate are usually set at equal intervals, and the brake pressure is applied to each of the wheel acceleration / deceleration and the slip rate. Is set. For example, as shown in FIG. 7, when the pressure increase / reduction amount is set to 0 and the pressure increase / reduction amount for each slip ratio λ is set in the case of the convergence target slip ratio λT, the table shows the pressure increase / reduction amount for the slip ratio λ at regular intervals a. Is set. When the actual slip ratio λ of the wheel is an intermediate value, the control is performed by the pressure increase / decrease amount of the smaller slip ratio λ. In this case, for example, if the slip rate lambda 2,
The control error ΔP1 between the ideal pressure increase / decrease amount and the pressure increase / decrease amount set in the table is large. Therefore, in order to enhance the convergence with respect to the convergence target slip ratio λT and perform precise brake control, the interval of the data set at the equal interval a is narrowed, and the data to be stored (the value of the pressure increase / decrease amount corresponding to the slip ratio λ) is stored. ) The number needs to be increased. However,
Increasing the number of data in this way not only increases the storage capacity, but also decreases the operation speed.

SUMMARY OF THE INVENTION The present invention has been made to solve such a problem, and has as its object to provide a brake control device capable of performing precise brake control with small storage capacity and good convergence. And

[0006]

In order to achieve the above object, the present invention provides a brake control for controlling the running stability and braking state of a vehicle body by increasing or decreasing a brake pressure according to the running state of the vehicle body. A wheel acceleration / deceleration detecting means for detecting a wheel acceleration / deceleration, a slip rate calculating means for obtaining a slip rate of a wheel with respect to a road surface, and a brake corresponding to the wheel acceleration / deceleration value and the slip rate value. Storage means for storing a table in which the amount of pressure increase / decrease is set, wherein the table sets the value of the wheel acceleration / deceleration and the value of the slip rate in the vicinity of the convergence target value of the wheel acceleration / deceleration and the slip rate. The resolution is set so that the further away from the convergence target value, the lower the resolution.

[0007]

In the brake control device according to the present invention, the amount of increase / decrease of the brake pressure is set for a predetermined wheel acceleration / deceleration value and a slip ratio value in a table stored in the storage means. In the vicinity of the convergence target values of the wheel acceleration / deceleration and the slip ratio, the value of the wheel acceleration / deceleration and the value of the slip ratio are set to high resolution, so that the convergence of the brake pressure with respect to the convergence target value is improved and the distance from the convergence target value is increased. The lower the resolution, the lower the storage capacity.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of a brake control device according to the present invention will be described below with reference to the accompanying drawings.

In FIG. 2, reference numeral 10 denotes a motorcycle. The motorcycle 10 includes a main body 12, a handle 14, a front wheel 16, and a rear wheel 18.

The motorcycle 10 has a brake control device 20 for implementing the brake control method according to the present embodiment.
Is arranged. As shown in FIG. 1, the brake control device 20 includes an antilock modulator 22, and a DC motor 24 constituting the modulator 22 has a pinion 26 mounted on a shaft, and a gear 28 meshes with the pinion 26. The gear 28 is supported by a crankshaft 30. One end of a crankpin 34 is eccentrically connected to the crankshaft 30 via a crank arm 32, and the other end of the crankpin 34 is A potentiometer 38 as a means for detecting the position of an expander piston (described later) is attached via a crank arm 36.

A cam bearing 4 is mounted on the crank pin 34.
The lower end of the cam bearing 40 is constantly pressed in the direction of the upper limit position under the action of the return spring 44 housed in the spring housing 42. An expander piston 46 contacts the upper end of the cam bearing 40, and the expander piston 46 is vertically displaced with the up and down movement of the cam bearing 40 to open and close the cut valve 48.

On the upper part of the expander piston 46,
A cut valve storage unit 50 containing a cut valve 48 is provided, and an input port 5 of the cut valve storage unit 50 is provided.
A master cylinder 56 is connected to 2 via a passage 54, while a caliper cylinder 62 for wheel braking is connected to an output port 58 of the cut valve housing 50 via a passage 60. The master cylinder 56 and the caliper cylinder 62 are connected to the passage 54, the modulator 22 and the passage 60.
And this path is filled with hydraulic oil. The master cylinder 56 adjusts the hydraulic pressure under the action of the brake lever 64, drives the caliper cylinder 62 via the cut valve 48, and
6 and a disk plate 66 disposed on the rear wheel portion 18
To the braking force.

Potentiometer 38 and DC motor 2
4 is connected to the motor controller 70. The motor controller 70 is connected to a control unit 72, and a memory 74 and an arithmetic circuit 80 are provided in the control unit 72. The memory 74 receives the wheel slip ratio λ and the wheel acceleration / deceleration α as inputs,
A table is stored which outputs an increase / decrease amount of the hydraulic pressure of the caliper cylinder 62 (hereinafter, referred to as a caliper pressure) (see FIG. 3). The control unit 72 is connected to a wheel speed sensor 76 mounted on the disk plate 66 and a vehicle acceleration / deceleration sensor 78 to an arithmetic circuit 80 for obtaining a slip ratio λ and a wheel acceleration / deceleration α.

In the table of this embodiment, 64 addresses are assigned to the slip rate λ and 256 addresses are assigned to the wheel acceleration / deceleration α. The data setting interval L and the data amount of α are set as follows.

As shown in FIGS. 4 and 5, the absolute values of the slip ratio λ and the wheel acceleration / deceleration α are set to 0, respectively.
The setting interval L between adjacent slip rate data or wheel acceleration / deceleration data is set to increase as the value increases from the vicinity. That is, the slip ratio λ
And the road surface friction coefficient, the braking performance and the running stability of the vehicle body are excellent, and the convergence target slip rate λT to be the control target is in the range of 0% to 10% of the slip rate λ set. A large memory area is used so that high-resolution data is concentrated in the range of ± 1.0 G of wheel acceleration / deceleration α from the running stability of the vehicle body. Conversely, for those having a large absolute value of the slip ratio λ or the wheel acceleration / deceleration α, the data has a low resolution and is sufficient, and a small memory area is set.

Next, the operation of the brake control device 20 according to the present embodiment configured as described above will be described.

During normal braking, the return spring 44
The resilient force holds the crank pin 34 at a preset upper limit position, and the cam bearing 40 mounted on the crank pin 34 is maintained in a state where the expander piston 46 is pushed up. As a result, the cut valve 48 is pushed up by the expander piston 46, and the input port 52 and the output port 58 communicate.

Then, the master cylinder 56 is urged by gripping the brake lever 64, and the brake oil pressure generated by the master cylinder 56 is applied to the passage 5
4, transmitted to the caliper cylinder 62 through the input port 52, the output port 58, and the passage 60, and a braking force is applied to the disk plate 66.

Next, at the time of brake control, the control unit 72 obtains the wheel acceleration / deceleration α and the slip ratio λ in the arithmetic circuit 80 based on the outputs from the wheel speed sensor 76 and the vehicle body acceleration / deceleration sensor 78. Based on the wheel acceleration / deceleration α and the slip ratio λ, the caliper pressure increase / decrease amount is set from a table stored in the memory 74, and the corresponding rotation amount of the DC motor 24 is output to the motor controller 70. As described above, when the drive signal is supplied from the control unit 72 to the motor controller 70 to perform the brake control, the DC motor 24
The rotation direction and the amount of rotation are controlled. For this reason,
A pinion 26 attached to a rotating shaft (not shown) is rotated to rotate a gear 28 meshing with the pinion 26 and a crank arm 32 fixed to the gear 28 via a crank shaft 30. The worn crank pin 34 is displaced from the upper limit position toward the lower limit position. The cam bearing 40 descends due to the deviation of the crank pin 34, and the brake oil pressure acting on the expander piston 46 acts so as to be added to the torque of the DC motor 24, so that the expander piston 46 presses the cam bearing 40. And descend immediately.

When the expander piston 46 descends by a predetermined amount, the cut valve 48 is seated, whereby the connection between the input port 52 and the output port 58 is shut off. Therefore, when the expander piston 46 further lowers further, the volume on the output port 58 side increases, and the hydraulic pressure applied to the caliper cylinder 62 decreases.
Braking force is reduced.

At this time, in the table, as shown in FIGS. 3 to 5, the caliper pressure rises in the range of the slip ratio λ, which is the control target, in the range of 0 to 10% and the wheel acceleration / deceleration α of ± 1.0 G. The data of the decompression amount is set intensively. For example, as shown in FIG. 6, even slip ratio lambda 1 convergence target slip ratio λT vicinity, control ideal temperature pressure reduction and set in the table has been elevated pressure reduction amount of caliper pressure error ΔP2
Is small, precise control is possible, and since a large number of data are set near the convergence target value, the oscillation width of the caliper pressure also decreases quickly and convergence to the target value is quick. Conversely, in a range where the absolute value of the slip ratio λ or the wheel acceleration / deceleration α is large, it is sufficient to set only a small number of data, so that the storage capacity of the entire memory can be reduced.

As described above, in this embodiment, the slip ratio λ
When calculating the caliper pressure increase / decrease amount from the wheel acceleration / deceleration α, the table shows the caliper pressure increase / decrease amount data in the vicinity of the target slip ratio, which is the convergence target, or within ± 1.0 G of the wheel acceleration / deceleration α. Since the settings are concentrated, the change in the caliper pressure with respect to the target value quickly decreases and converges to the target value. Further, where the value of the slip ratio λ or the wheel acceleration / deceleration α is large, the data is set with a small number of data and the memory area used is reduced, so that the storage capacity of the entire memory can be reduced.

[0023]

According to the brake control device of the present invention, the following effects can be obtained.

That is, in the table stored in the storage means, the amount of increase / decrease in the brake pressure is set for a predetermined value of the wheel acceleration / deceleration and a value of the slip ratio.
In the vicinity of the convergence target value of the wheel acceleration / deceleration and the slip rate, the value of the wheel acceleration / deceleration and the value of the slip rate are set to high resolution, so that the convergence of the brake pressure convergence target value is improved, and the convergence target value is improved. Since the resolution increases as the distance increases, the storage capacity is reduced.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a brake control device according to the present invention.

FIG. 2 is a schematic external view of a motorcycle incorporating the brake control device according to the present invention.

FIG. 3 is an explanatory diagram of a table used in the brake control device according to the present invention.

FIG. 4 is a diagram showing a relationship between a slip ratio and a set interval of an address number or a pressure increase / decrease amount in a table of the brake control device according to the present invention.

FIG. 5 is a diagram showing a relationship between a wheel acceleration / deceleration and a setting interval of an address number or a pressure increase / decrease amount in a table of the brake control device according to the present invention.

FIG. 6 is a graph showing the relationship between the slip ratio of the table used in the brake control device according to the present invention and the amount of increase and decrease in caliper pressure.

FIG. 7 is a diagram showing a relationship between a slip ratio of a table used in a brake control device according to a conventional example and a pressure increase / decrease amount of a brake pressure.

[Explanation of symbols]

 Reference Signs List 20 brake controller 22 modulator 24 DC motor 34 crank pin 38 potentiometer 40 cam bearing 46 expander piston 56 master cylinder 62 caliper cylinder 66 disk plate 70 motor controller 72 control unit 74 Memory 80: arithmetic circuit

Claims (1)

(57) [Claims] 1. A brake control device for controlling a running stability and a braking state of a vehicle body by increasing and decreasing a brake pressure according to a running state of the vehicle body, comprising: a wheel acceleration / deceleration detecting means for detecting a wheel acceleration / deceleration; A slip rate calculating means for calculating a slip rate of a wheel with respect to a road surface; and a storage means for storing a table in which a brake pressure increase / decrease amount is set in accordance with the wheel acceleration / deceleration value and the slip rate value. The table sets the value of the wheel acceleration / deceleration and the value of the slip rate to high resolution near the convergence target value of the wheel acceleration / deceleration and the slip rate, and the lower the distance from the convergence target value, the lower the resolution. A brake control device characterized by setting as follows.