JPH10157609A - Brake fluid pressure controller for automobile - Google Patents

Abstract

PROBLEM TO BE SOLVED: To set a threshold value which is effective even when viscosity of working fluid is changed by correcting a threshold value, which is used for comparison with an operation speed detection means of a brake operation member when action of the second braking force generating means is controlled, on the basis of the detection result of a temperature detection means. SOLUTION: A temperature (x) as a detection output of a temperature sensor is compared with a set temperature T deg.C (step 201), and if the temperature (x) is lower than the set temperature T deg.C, low temperature is determined and a threshold value correction ratio is computed from A×(x-T)+1 (step 202), and the computed threshold value correction ratio, which is smaller than 1, and an ideal threshold THo are multiplied together so that the threshold value THo is corrected to a threshold value TH suitable for a low temperature. When the temperature (x) is higher than the set temperature T deg.C, a high temperature is determined and a threshold correction ratio is computed from B×(x-T)+1 (step 203), and the computed threshold value correction ratio, which is larger than l, and the ideal threshold THo are multiplied together so that the threshold value THo is corrected to a threshold value TH suitable for a high temperature.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a brake fluid pressure control device for a vehicle, and more particularly, to a brake fluid pressure control device for a vehicle which determines the start sensitivity of an automatic braking process of the vehicle in relation to the state of the vehicle. About.

[0002]

2. Description of the Related Art A conventional vehicle brake fluid pressure control device is disclosed in, for example, Japanese Patent Application Laid-Open No. 7-76267.
A brake operation member, and a first braking force generating means for applying a first braking force to the wheel by operating the brake operation member so that hydraulic fluid is pressed and urged toward the wheel by the brake operation member. A second braking force generating unit that adds a second braking force to the first braking force, an operation speed detection unit that detects an operation speed of the brake operation member,
Comparing means for comparing a detection result of the operation speed detecting means with a threshold value;
And control means for operating the braking force generating means.

This conventional vehicle brake fluid pressure control device is
Normally, when the brake operation member is operated, the hydraulic fluid is pressed and urged toward the wheel, so that the first braking force is applied to the wheel. On the other hand, when the brake operating member is operated at a speed exceeding the threshold, the second braking force generating means is operated, and the second braking force is added to the first braking force,
This is to increase the braking force of the vehicle.

[0004]

In an automobile brake fluid pressure control system, the operating speed of a brake operating member generally depends on the flow speed of hydraulic fluid. Further, the flow speed of the working fluid changes depending on the viscosity of the working fluid. In particular, the viscosity of the working fluid is easily affected by the temperature. For example, when the temperature is low, the viscosity increases, and when the temperature is high, the viscosity decreases. Further, if the viscosity of the hydraulic fluid is large, the operation speed of the brake operation member is slow, and if the viscosity is small, the operation speed is high.

However, the above-mentioned Japanese Patent Application Laid-Open No. 7-762 has been disclosed.
The threshold value does not correspond to the fluctuation of the operation speed of the brake operation member due to the change in the viscosity of the hydraulic fluid in the vehicle brake fluid pressure control device disclosed in Japanese Patent Publication No. 67-67. In other words, when the temperature is low, even if the driver intends to perform a sudden braking operation,
The brake operation speed becomes slower than usual due to a change in the viscosity of the hydraulic fluid. Therefore, the threshold value may not be exceeded despite the sudden braking, and it may be determined that normal brake operation is performed.

SUMMARY OF THE INVENTION An object of the present invention is to provide an automobile brake fluid pressure control device capable of setting an effective threshold value even when the viscosity of the hydraulic fluid changes.

[0007]

In order to solve the above technical problem, a brake operating member and a hydraulic fluid are urged toward the wheels by the brake operating member by operating the brake operating member. A first braking force generating means for applying a first braking force to the wheel;
Second braking force generating means for adding a second braking force to the braking force;
Operating speed detecting means for detecting an amount relating to the operating speed of the brake operating member; comparing means for comparing the detection result of the operating speed detecting means with a threshold; and the second braking force based on the comparison result of the comparing means An automotive brake fluid pressure control device includes a control unit for operating the generation unit, an air temperature detection unit for detecting an air temperature, and a correction unit for correcting the threshold based on the detection result of the air temperature detection unit.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to embodiments.

As shown in FIG. 1, reference numeral 1 denotes a brake fluid pressure control device for a vehicle, which includes a brake pedal 15, a negative pressure booster 2 and a master cylinder 3 as a fluid pressure generation device, and an ABS as a fluid pressure control device. (Anti-lock brake system)
4. Stroke sensor 2 constituting operation speed detecting means
9, an air temperature sensor 31 as an air temperature detecting means, and an electronic control unit 32 are provided.

The vacuum booster 2 will be described in detail. The housing 10 of the negative pressure booster 2 has a movable wall 11 whose outer peripheral portion is hermetically fixed and movable in the axial direction. The inside of the housing 11 is airtightly separated into a constant pressure chamber 12 and a variable pressure chamber 13 by the movable wall 11. The constant-pressure chamber 12 communicates with an intake manifold of a vehicle engine (not shown), which is a negative pressure source, via an inlet 10a, and constantly generates a negative pressure.

A power piston 14 made of a resin material is inserted into the housing 10 from the rear thereof, and the movable wall 11 is air-tightly fixed to the power piston 14 at an inner peripheral end thereof.

Inside the power piston 14, an input rod 16 connected to a brake pedal 15 which is a brake operating member of the vehicle at the right end in FIG. 1 is inserted. The input rod 16 is connected to an input member 17 described later so as to be integrally movable.

The input member 17 has a function of transmitting the brake operation force from the input rod 16 to the reaction disk 18. The output rod 19 in contact with the reaction disc 18 receives a brake operation force via the reaction disc 18 and moves, thereby causing the master cylinder 3 to move.
Activate the piston.

A first retainer for receiving the return spring 20 is fixed to the input rod 16. A second retainer that supports the right end of the control valve 21 is fixed to the power piston 14 while receiving elastic force from the input rod 16 via the first retainer and the return spring 20. The control valve 21 is engaged with the second retainer at the inner periphery at the right end in the figure, and has a sealing function with the power piston 14 at the outer periphery.
The seal portion 21a at the left end of the control valve 21
A valve spring 22 is interposed between the retainer that supports the first spring and the first retainer.

With the above configuration, the seal portion 21a of the control valve 21 is engaged with the air valve valve seat 17a formed at the rear end of the input member 17 when the input rod 16 is not operated. Also, the input rod 16
Is in the operating state, the seal portion 21a can be engaged with the vacuum valve valve seat 14a provided on the power piston 14.

In the constant pressure chamber 12, an auxiliary movable wall 23 as a partition plate capable of engaging with the flange portion of the output rod 19 is installed at an inner peripheral portion thereof. The auxiliary movable wall 23 has an inner peripheral portion and an outer peripheral portion. The airtight engagement with a diaphragm 24 provided with a sealing bead at each portion thereof forms an auxiliary transformation chamber 25 which is an air introduction chamber therebetween. Auxiliary movable wall 2
Numeral 3 is biased by the return spring 26 from the housing 10. An air passage 2 as an elastic air introduction passage airtightly connected at one end to an auxiliary movable wall 23;
Numeral 7 penetrates the constant pressure chamber 12 and hermetically engages an electromagnetic valve 28 described later at the other end. That is, the air passage 27
Is connected to the solenoid valve device 28.

The output rod 19 has a first output rod 191 on the power piston 14 side and a second output rod 191 on the master cylinder 3 side.
And an output rod 192.

FIG. 2 is an enlarged view of the solenoid valve device 28 of FIG. As shown in FIG. 2, an electromagnetic valve device 28 as a switching means for selectively connecting the auxiliary variable pressure chamber 25 of the negative pressure type booster 2 to the constant pressure chamber 12 or the atmosphere is air-tightly disposed on the front surface of the housing 10. Has been established.

The valve housing 28a of the solenoid valve device 28
Is provided therein with a constant-pressure port 28 communicating with the constant-pressure chamber 12.
b, Atmospheric port 28 communicating with air cleaner for air introduction
c, a transformation port 28d connected to the atmosphere passage 27, a constant pressure valve seat 28e communicating the constant pressure chamber 12 with the auxiliary transformation chamber 25, an atmosphere valve seat 28f communicating the atmosphere with the auxiliary transformation chamber 25, and a valve body at the tip. A valve body 28h provided with a certain valve 28g, a movable core 28i, and a movable core 28i at one end (left end) side thereof.
Rod portion 28j that can be brought into contact with
k.

The solenoid 28k is connected to a power source of a vehicle (not shown) by a terminal 28l, and is operated by being supplied with power from the power source by a controller of the vehicle (not shown).

In the non-operating state shown in FIG.
8g is disengaged from the constant pressure valve seat 28e,
The auxiliary variable pressure chamber 25 communicates with the constant pressure chamber 12 via the inside of the atmosphere introduction passage 27, the variable pressure port 28d, the gap between the valve 28g and the constant pressure valve seat 28e, and the constant pressure port 28b.

On the other hand, when power is supplied from a power source to the solenoid 28k by the controller of the vehicle (not shown) as described above, the solenoid 28k suctions the movable core 28i, and the movable core 28i slides rightward in FIG. Therefore, the movable core 28i presses the rod 28j, and the movable core 28i and the rod 28j move integrally to the right in FIG.

The right end of the rod 28j urged by the movable core 28i abuts the left end of the valve body 28h, and the rod 28j presses the valve 28h rightward in FIG. The valve 28g contacts the constant pressure valve seat 28e,
In addition, the valve 28g and the atmosphere valve seat 28f are disengaged.

Accordingly, the auxiliary transformer chamber 25 is connected to the inside of the atmosphere introduction passage 27, the transformation port 28h, the gap between the valve 28g and the atmosphere valve seat 28f, the communication hole, the atmosphere port 28c, and the atmosphere introduction air cleaner. Atmosphere is introduced from a vehicle interior space (not shown).

The ABS (anti-lock brake system) 4 shown in FIG. 1 has a hydraulic line through which the brake fluid flows, an electromagnetic valve device for blocking the flow of the brake fluid in the hydraulic line, and a brake fluid reservoir. And a pump unit for sucking and discharging the brake fluid.

Normally, the master cylinder 3 and the ABS (anti-lock brake system) 4 are connected to the wheels FR, FL, R via hydraulic pressure according to the output from the output rod 19.
This is a system that acts on R and FL to temporarily reduce the braking force when the difference between the speed of the vehicle body and the speed of the wheel increases, thereby preventing the wheel from slipping. It is electrically connected to the electronic control unit 32.

The brake pedal 15 is provided with a stroke sensor 29 for detecting the stroke amount of the brake pedal 15, and further provided with a brake switch 30 for turning on a brake light in accordance with the operation of the brake pedal 15. ing. The stroke sensor 29 and the brake switch 30 are each electrically connected to the electronic control unit 32.

The electronic control unit 32, as shown in FIG.
CPU 33, ROM 3 mutually connected via a bus
4, a microcomputer 39 comprising a RAM 35, a timer 36, an input port 37, and an output port 38. The stroke sensor 29, the brake switch 3
0 and the output signal of the air temperature sensor 31
Through the input port 37 to the CPU 3
3 is input. Further, a control signal is output from the output port 38 to a solenoid 28k via a solenoid drive circuit 41 as an automatic braking process control means, and the ABS is transmitted via a braking force control circuit 42.
(Anti-lock brake system) 4 is configured to output a control signal. Microcomputer 3
9, the ROM 34 stores a program corresponding to each of the flowcharts shown in FIGS. 5 and 6 and a program for controlling the ABS, and the CPU 33 executes the program while an ignition switch (not shown) is closed. Temporarily stores variable data necessary for executing the program.

Next, the operation of the vehicle brake fluid pressure control device 1 according to the present embodiment will be described with reference to FIGS.
FIG. 4 is a characteristic diagram of the negative pressure booster 2 in the present embodiment, in which the vertical axis represents the brake output, and the horizontal axis represents the operating force applied to the brake pedal 15, and FIG. FIG. 6 is a flowchart of a threshold correction, and FIG. 7 is a correlation diagram between a temperature and a threshold correction ratio according to the present embodiment. The driver operates the brake pedal 15 which is a brake operating member of the vehicle.
Is operated, the input rod 16 connected thereto moves to the left in FIG. 1 under the brake operating force. Therefore, the input member 17 fixed to the input rod 16 also moves to the left in FIG.

When the brake pedal 15 is operated, the brake switch 30 sends an ON signal to the electronic control unit 3.
2 to turn on the brake lights.

The movement of the input member 17 causes the control valve 21 and thus the seal portion 21a to move to the left in FIG. 1 together with the input member 17 by the urging force of the valve spring 22. The variable pressure chamber 13 is cut off from the constant pressure chamber 12 by contacting the seat 14a, so that the communication with the negative pressure source of the vehicle is also cut off.

Further, when the input member 17 moves to the left in FIG. 1, the engagement between the seal portion 21a and the air valve valve seat 17a of the input member 17 is released, and the variable pressure chamber 13 communicates with the atmosphere. Accordingly, the atmospheric pressure flows into the variable pressure chamber 13 to generate a pressure difference between the constant pressure chamber 12 and the variable pressure chamber 13, so that the movable wall 11 loaded with the pressure difference and the power piston 14 connected thereto are loaded. Pushes the output rod 19 to the left via the reaction disk 18.

When the output rod 19 is depressed to the left, the power piston 14 outputs the amplified braking force to the output rod 19.

The braking force is output to the output rod 19,
When the output rod 19 is moved to the left in FIG. 1, the piston of the master cylinder 3 is pressed, and the brake fluid
(Anti-lock brake system) Flows out to the wheel cylinder via the wheel 4 and the wheels FR, FL, RR, R of the vehicle
L is given a braking force. That is, in the present embodiment, the negative pressure booster 2, the master cylinder 3, and the ABS
4 together form a first braking force generating means.

In this normal operation state, since the solenoid 28k is in the non-operation state, the auxiliary variable pressure chamber 25 is in communication with the constant pressure chamber 12, and there is no pressure difference between the front and rear of the auxiliary movable wall 23, and the auxiliary movable wall 23 Is inactive. The relationship between the brake operating force applied to the brake pedal 15 and the brake output applied to the output rod 19 at this time is shown in FIG.
Is shown in diagram A.

On the other hand, the wheel speed of the wheels FR, FL, RR, RL is detected by a wheel speed sensor (not shown), and an ABS (anti-lock brake system) 4 is driven in accordance with the detected output of the wheel speed sensor, The brake fluid pressure supplied to the cylinder is controlled so that the wheels FR, F
The braking force for L, RR, RL is appropriately controlled.

When the depression of the brake pedal 15 is released, the input rod 16 moves toward the outside of the power piston 14, and with the movement of the input rod 16, the valve plunger 17 slides inside the power piston 14, and the air valve valve The seat 17a comes into contact with the seal portion 20a to cut off the communication between the transformation chamber 13 and the atmosphere, and the further movement of the valve plunger 17 causes the seal portion 20a to be pressed and urged by the valve plunger 17, so that the seal portion 20a becomes a vacuum valve. It separates from the valve seat 14a, makes the constant pressure chamber 12 and the variable pressure chamber 13 communicate with each other, the atmosphere in the variable pressure chamber 13 flows into the constant pressure chamber 12, and the pressure difference between the constant pressure chamber 12 and the variable pressure chamber 13 disappears, The movable wall 11 and the power piston 14 return to the initial positions. With the return of the power piston 14 to the initial position, the output rod 19 also returns to the initial position, so that the master cylinder 3 lowers the hydraulic pressure and releases the brakes on the wheels FR, FL, RR, RL of the vehicle. In addition, with the return of the brake pedal 15 to the initial position, the brake switch 30
The FF signal is transmitted to the electronic control unit 32, and the lighting of the brake light is stopped.

Next, the operation of the vehicle brake fluid pressure control device 1 in which the threshold value is corrected and the automatic braking process is performed will be described. When an ignition switch (not shown) is closed, execution of a program corresponding to the flowcharts of FIGS. 5 and 6 is started. When the program starts running,
In steps 101 and 102 and the ABS control program, the electronic control unit 32 performs an initial setting and an initial check. Then, in step 103, the timer 3
The main routine of Steps 104 to 111 or 112 is executed at a fixed period (6 ms) checked by Step 6.

In step 104, the electronic control unit 3
2 is a stroke sensor 29, a brake switch 30,
Various input data from the temperature sensor 31, the timer 41 and the like are taken.

In step 105, the depression amount ST0 of the brake pedal 15 from the stroke sensor 29
(Mm) and one cycle before (6m
s) The depression amount ST of the brake pedal 15 detected in
1 (mm) and the time required for one cycle of the main routine (6 ms), the brake pedal depressing speed V
p0 (mm / sec) is calculated. That is, the brake pedal 1
5 is the depression amount S of the brake pedal 15 from the stroke sensor 29 detected by the depression operation of the pedal 5
One cycle before (6 ms) in the main routine from T0
, The depression amount ST1 of the brake pedal 15 detected at the time is reduced, and the difference between ST0 and ST1 is divided by the time required for one cycle of the main routine, that is, 6 ms.
The brake pedal depression speed Vp0 is calculated.

In step 106, failure detection of each sensor and the like is performed.

Next, at step 107, a threshold value TH (mm / sec) described later is corrected.

In step 108, it is determined whether or not the automatic braking process has been started. If the automatic braking process has been started, the process proceeds to step 109, and if not, the process proceeds to step 110.

In step 110, it is determined whether a condition for starting the automatic braking process is satisfied. In the present embodiment, the brake switch 30 transmits an ON signal, and the brake pedal depressing speed Vp0 calculated in step 105 is compared with the threshold value TH of the brake pedal depressing speed corrected in step 107.
If the brake pedal depressing speed Vp0 is equal to or higher than the threshold value TH of the brake pedal depressing speed, the operation of the brake pedal 15 is determined to be a sudden braking operation, and the routine proceeds to step 112. Stepping on the pedal 17 is determined to be a normal brake operation, and the automatic braking process is not performed.
Return to 03.

In step 112, a signal is sent to the solenoid drive circuit 41 to drive the solenoid 28k in order to perform the automatic braking process.
k is driven.

When the solenoid 28k is driven, the movable core 28k resists the urging force of the spring as shown in FIG.
Is moved to the right.

As described above, since the atmosphere is introduced into the auxiliary transformation chamber 25 by the movement of the movable core 28k, a pressure difference occurs before and after the auxiliary movable wall 23, and the auxiliary movable wall 2
3 is moved to the left in FIG.

As the auxiliary movable wall 23 moves,
The second output rod 192 is provided on the inner peripheral portion of the auxiliary movable wall 23.
Of the second output rod 19
1 is moved by applying a load leftward in FIG.

Since the load applied to the second output rod 192 does not act on the reaction disk 18, it does not become a reaction force on the input member 17, but is purely increased as a brake output.

By the movement of the second output rod 192, the hydraulic pressure of the master cylinder 3 is increased, and the wheels FR, FR of the vehicle are transmitted through an ABS (anti-antilock brake system) 4.
Apply brakes to FL, RR and RL. A if necessary
The operation of the BS (anti-antilock brake system) 4 is performed.

By introducing the atmosphere into the auxiliary transformer chamber 25, the brake output acting on the output rod 19 is increased by a certain amount for the same brake operation force acting on the brake pedal 15 as compared to when the pressure in the auxiliary transformer chamber 25 is negative. . The relationship between the brake operation force applied to the brake pedal 15 and the brake output applied to the output rod 19 at this time is shown by a diagram B in FIG. That is, an automatic braking process is performed that automatically establishes a higher braking pressure resulting from the brake pedal position. That is, in the present embodiment, the solenoid 28k is connected to the negative pressure type booster 2, the master cylinder 3, and the ABS (anti-antilock brake system) 4.
The second braking force generating means is configured so that the additional braking force is exerted when is operated.

When the automatic braking process is performed, step 11
2 to step 103, and steps 104, 10
Proceed to step 108 via 5, 106, 107,
In step 108, since the automatic braking process is being performed, the process proceeds to step 109.

In step 109, it is determined whether an automatic braking process end condition has been satisfied. In the present embodiment, it is determined whether or not the brake switch 30 is transmitting an OFF signal to the electronic control unit 32. If the brake switch 30 is transmitting the OFF signal, step 1 is performed.
Proceed to step 11; otherwise, return to step 103.

That is, when the depression of the brake pedal 15 is released, the input rod 16 moves toward the outside of the power piston 14, and the input member 17 moves rightward integrally with the input rod 16 by retreating the input rod 16. Go to
The seal member 21a of the control valve 21 is the input member 1
7 and the sealing portion 21a is separated from the valve seat 14a of the power piston 14, so that the variable pressure chamber 13 is cut off from the atmosphere, communicates with the constant pressure chamber 12, and the degree of negative pressure in the variable pressure chamber 13 increases again. The assisting force to the power piston 14 also decreases, and the power piston 14 and the input rod 16 are moved rightward in FIG. 1 by the reaction force from the master cylinder 3 and the return spring 26 in the booster. Complete the process. On the other hand, with the return of the brake pedal 15 to the initial position, the brake switch 29
The FF signal is transmitted to the electronic control unit 32.

In step 109, the electronic control unit 3
2 receives the OFF signal of the brake switch 30,
The drive of the solenoid 28k is released, and the automatic braking process ends. That is, since the driving of the solenoid 28k is released, the solenoid 28k no longer generates an electromagnetic force to the movable core 28i, and the movable core 28i is moved leftward in FIG. 2 by the urging force of the spring via the rod 28j. Is returned to. In addition, the valve body 28h is urged leftward in FIG. 2 by the urging force of the spring, so that the valve 28g is separated from the constant-pressure valve seat 28e and comes into contact with the atmospheric valve seat 28f.

By moving the movable core 28i and the valve body 28h to the left in FIG. 2, the auxiliary variable pressure chamber 25 is cut off from the atmosphere and communicates again with the constant pressure chamber 12, and the auxiliary movable wall 23 is initialized by the return spring 26. Pushed back toward the position, the engagement between the inner peripheral portion of the auxiliary movable wall 23 and the flange portion of the second output rod 192 is released, and the initial state is completely restored. By returning the second output rod 192 to the initial position,
The master cylinder 3 lowers the hydraulic pressure, and the wheels FR, F of the vehicle
Release the brakes of L, RR and RL. That is, the automatic braking process ends.

The correction of the threshold value Vpt in step 107 is performed by executing the flowchart shown in FIG.

First, in step 201, the temperature x (° C.) input as the detection output of the temperature sensor 31 in step 104 is compared with the set temperature T, which is 10 (° C.) in the present embodiment. If the temperature x is the set temperature T
If it is lower than the current temperature, the current temperature is determined to be low, and the process proceeds to step 202; otherwise, the temperature is determined to be high, and the process proceeds to step 204.

Next, in step 202, first, K = A × (x−T) shown as a correlation characteristic line a in FIG.
A threshold correction ratio K is calculated from the temperature x based on a regression equation of +1. A in the regression equation of the correlation characteristic line a indicates a characteristic coefficient, and is set to 0.01 in the present embodiment. The threshold correction ratio K calculated in step 202 is indicated by a value lower than 1. Then, TH = TH
Based on the regression equation represented by 0 × K, the threshold correction ratio K calculated previously and an ideal threshold TH0 set in advance
Is multiplied, the threshold value TH0 is corrected to a threshold value TH suitable for a low temperature.

In step 203, first, a threshold value correction ratio K is calculated from the temperature x based on a regression equation of K = B × (x−T) +1 shown as a correlation characteristic line b in FIG. B in the regression equation of the correlation characteristic line b indicates a characteristic coefficient, and is set to 0.002 in the present embodiment. The threshold correction ratio K calculated in step 203 is indicated by a value larger than 1. Then, TH = TH
Based on the regression equation represented by 0 × K, the threshold correction ratio K calculated previously and an ideal threshold TH0 set in advance
Is multiplied, the threshold value TH0 is corrected to a threshold value TH suitable for high temperature.

As described above, according to the vehicle brake fluid pressure control apparatus 1 of the present embodiment, the threshold value can be corrected according to the outside air temperature. That is, when the temperature is low, the flow speed of the hydraulic fluid decreases with the change in the viscosity of the hydraulic fluid in the vehicle brake fluid pressure control device 1, and the operating speed of the brake pedal 15 also decreases. However, when the temperature is low, the threshold value is corrected to be low, so that it is possible to reliably detect a sudden brake operation in response to a decrease in the operation speed of the brake pedal 15. Conversely, when the temperature is high, the flow speed of the hydraulic fluid increases with a change in the viscosity of the hydraulic fluid in the vehicle brake fluid pressure control device 1,
As a result, the operation speed of the brake pedal 15 also increases.
However, when the temperature is high, the threshold value is corrected to be high, so that it is possible to reliably detect a sudden braking operation in response to an increase in the operation speed of the brake pedal 15.

Accordingly, it is possible to provide an automotive brake fluid pressure control device 1 which can set an effective threshold value even when the viscosity of the hydraulic fluid changes.

In the present embodiment, 10 ° C. is used as the set temperature when judging the low air temperature and the high air temperature, but it goes without saying that the present invention is not particularly limited to this. In the present embodiment, K = A × (x−T) +1 and K = B × (x−T) when calculating the correction ratio K.
Although +1 is used, it is needless to say that the present invention is not particularly limited to this.

In this embodiment, TH = TH
Although the threshold value is corrected based on the equation of 0 × K, it is needless to say that the threshold value is not particularly limited to this.

In this embodiment, the depression amount of the brake pedal 15 is detected directly from the brake pedal 15 for detecting the depression amount of the brake pedal 15, but it is not particularly limited to this configuration. Needless to say.

In the present embodiment, the automatic braking process is generated from the position of the brake pedal by activating the boosting action by supplying power to and driving the solenoid 28k in the vacuum booster 2. A larger braking pressure is automatically established. For example, as a hydraulic pressure control device including a pump unit that can independently apply hydraulic pressure to each wheel cylinder of the wheels FR, FL, RR, and RL. The invention relates to an ABS (Anti-Lock Brake System) in which the pump unit is actuated to exert a braking force on the wheels, thereby automatically establishing a greater braking pressure resulting from the brake pedal position. The same operation and effect can be obtained also in an automobile braking device.

In the present embodiment, the braking force generating means includes the negative pressure type booster 2, the master cylinder 3,
Although a BS (anti-skid control system) 4 is provided, it is needless to say that the configuration is not particularly limited to this configuration, and that the configuration of the negative pressure booster 2 is not limited to the above configuration. Needless to say.
Further, in the present embodiment, the processing after step 104 is performed every 6 ms, but it goes without saying that the present invention is not particularly limited to this configuration.

Further, in the present embodiment, the brake pedal depressing speed Vp0 is used as the quantity relating to the operating speed of the brake operating member. However, the present invention is not limited to this. The same operation and effect can be obtained also in the vehicle braking device of the present invention using the rate at which the master cylinder pressure is increased as the related quantity.

In the present embodiment, the depression amount ST of the brake pedal 15 from the stroke sensor 29 is set.
0 (mm) and one cycle before (6m
s) The depression amount ST of the brake pedal 15 detected in
1 (mm) and the time required for one cycle of the main routine (6 ms), the brake pedal depressing speed V
Although p0 (mm / sec) is calculated, it is needless to say that the configuration is not limited to a specific configuration.

Although the present invention has been described based on the above embodiment, the present invention is not limited to the above embodiment, but includes various embodiments according to the principle of the present invention.

[0071]

As described above, according to the present invention,
The threshold can be corrected according to the outside temperature. Therefore,
It is possible to provide an automotive brake fluid pressure control device capable of setting an effective threshold value even when the viscosity of the hydraulic fluid changes.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a vehicle brake fluid pressure control device 1 according to the present embodiment.

FIG. 2 is a partially enlarged sectional view of the negative pressure type booster 2 of FIG.

FIG. 3 is a block diagram showing a configuration of an electronic control device 32 of FIG. 1;

FIG. 4 is a characteristic diagram of the vacuum booster 2 of the present embodiment.

FIG. 5 is a flowchart of an automatic braking process according to the embodiment.

FIG. 6 is a flowchart of threshold value correction according to the embodiment.

FIG. 7 is a regression diagram relating to air temperature and a threshold correction ratio according to the present embodiment.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 brake fluid pressure control device for automobile 2 negative pressure booster 3 master cylinder 4 ABS 15 brake pedal 30 stroke sensor 31 temperature sensor 32 electronic control device FR, FL, RR, RL wheel

Claims (1)

[Claims] A brake operating member, and a hydraulic fluid is pressed and urged toward a wheel by the brake operating member by operating the brake operating member, and a first braking force is applied to the wheel. (1) braking force generation means, second braking force generation means for adding a second braking force to the first braking force, operation speed detection means for detecting an amount related to the operation speed of the brake operating member, and operation speed detection Comparing means for comparing the detection result of the means with a threshold value, control means for activating the second braking force generating means based on the comparison result of the comparing means, temperature detection means for detecting air temperature, A brake fluid pressure control device for a vehicle, comprising: a correction unit that corrects based on a detection result of the air temperature detection unit.