JP3906505B2 - Brake fluid pressure control device for automobiles - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an automobile brake fluid pressure control apparatus, and more particularly to an automobile brake fluid pressure control apparatus that determines the start sensitivity of an automobile automatic braking process in relation to the state of the vehicle.
[0002]
[Prior art]
As disclosed in, for example, Japanese Patent Application Laid-Open No. 7-76267, a conventional brake fluid pressure control device for an automobile has a brake operation member, and a hydraulic fluid is driven by a wheel by the brake operation member when the brake operation member is operated. A first braking force generating means for applying a first braking force to the wheel, a second braking force generating means for adding a second braking force to the first braking force, Operating speed detecting means for detecting 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 generating means based on the comparison result of the comparing means. Control means to be operated.
[0003]
In the conventional brake fluid pressure control device for an automobile, the hydraulic fluid is normally pressed and urged toward the wheel by operating the brake operation member, and the first braking force is applied to the wheel. become. On the other hand, when the brake operating member is operated at a speed exceeding the threshold value, the second braking force generating means is activated, the second braking force is added to the first braking force, and the braking force of the vehicle is increased. It is.
[0004]
[Problems to be solved by the invention]
In an automobile brake fluid pressure control apparatus, the operation speed of a brake operation member generally depends on the flow speed of hydraulic fluid. Furthermore, the flow rate of the hydraulic fluid varies depending on the viscosity of the hydraulic fluid. In particular, the viscosity of the hydraulic 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. Furthermore, 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 fast.
[0005]
However, the braking fluid pressure control apparatus for automobiles disclosed in the above-mentioned Japanese Patent Application Laid-Open No. 7-76267 does not correspond to a threshold for fluctuations in the operation speed of the brake operation member accompanying such changes in the viscosity of the hydraulic fluid. . That is, when the temperature is low, even if the driver intends to perform a sudden brake operation, the brake operation speed becomes slower than usual due to a change in the viscosity of the hydraulic fluid. There is a possibility that it is determined to be an operation.
[0006]
An object of the present invention is to provide an automobile brake fluid pressure control device capable of setting an effective threshold even when the viscosity of hydraulic fluid changes.
[0007]
[Means for Solving the Problems]
In order to solve the technical problem, the brake operating member and the brake operating member are operated to press and urge the hydraulic fluid toward the wheel by the brake operating member. First braking force generation means for applying power; second braking force generation means for adding a second braking force to the first braking force; and an operation speed detection means for detecting an amount related to the operation speed of the brake operation member. A comparison means for comparing the detection result of the operation speed detection means with a threshold value, and based on the comparison result of the comparison means When the operation speed of the brake operation member is equal to or higher than the threshold value Control means for operating the second braking force generating means, temperature detecting means for detecting the temperature, Correction means for correcting the threshold value to be low when the temperature detected by the temperature detection means is low and to correct it when the temperature detected by the temperature detection means is high. A braking fluid pressure control device for an automobile provided with
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be specifically described with reference to embodiments.
[0009]
As shown in FIG. 1, reference numeral 1 denotes an automotive braking hydraulic pressure control device, which includes a brake pedal 15, a negative pressure booster 2 and a master cylinder 3 as a hydraulic pressure generating device, and an ABS (anti-lock) as a hydraulic pressure control device. Brake system) 4, a stroke sensor 29 constituting an operation speed detecting means, an air temperature sensor 31 as an air temperature detecting means, and an electronic control device 32.
[0010]
The negative pressure booster 2 will be described in detail. In the housing 10 of the negative pressure booster 2, an outer peripheral portion thereof is hermetically fixed, and a movable wall 11 that is movable in the axial direction is provided. The inside of the housing 11 is hermetically 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 negative pressure.
[0011]
A power piston 14 made of a resin material is inserted into the housing 10 from behind, and a movable wall 11 is airtightly fixed to the power piston 14 at the inner peripheral end thereof.
[0012]
Inside the power piston 14 is inserted an input rod 16 connected to a brake pedal 15 which is a vehicle brake operation member at the right end in FIG. The input rod 16 is connected to an input member 17 described later so as to be integrally movable.
[0013]
The input member 17 serves to transmit the brake operation force from the input rod 16 to the reaction disk 18. The output rod 19 in contact with the reaction disk 18 receives the brake operation force via the reaction disk 18 and moves to actuate the piston of the master cylinder 3.
[0014]
A first retainer that receives 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 an 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 of the right end in the figure, and generates a sealing function with the power piston 14 at the outer periphery. A valve spring 22 is interposed between the retainer that supports the seal portion 21 a that is the left end portion of the control valve 21 and the first retainer.
[0015]
By adopting the above configuration, the seal portion 21a of the control valve 21 is engaged with an air valve valve seat 17a formed at the rear end of the input member 17 when the input rod 16 is in an inoperative state. Further, when the input rod 16 is in an operating state, the seal portion 21 a can be engaged with a vacuum valve valve seat 14 a provided on the power piston 14.
[0016]
In the constant pressure chamber 12, an auxiliary movable wall 23 is installed as a partition plate that can be engaged with the flange portion of the output rod 19 at the inner peripheral portion thereof, and the auxiliary movable wall 23 is provided at the inner peripheral portion and the outer peripheral portion, respectively. A diaphragm 24 provided with a sealing bead is hermetically engaged, and an auxiliary variable pressure chamber 25, which is an atmosphere introduction chamber, is formed between the two. The auxiliary movable wall 23 receives a biasing force from the housing 10 by a return spring 26. An air passage 27 as a telescopic atmosphere introduction passage that is airtightly connected to the auxiliary movable wall 23 at one end passes through the constant pressure chamber 12 and is airtightly engaged with a later-described electromagnetic valve 28 at the other end. That is, the air passage 27 communicates with the electromagnetic valve device 28.
[0017]
The output rod 19 includes a first output rod 191 on the power piston 14 side and a second output rod 192 on the master cylinder 3 side.
[0018]
FIG. 2 is an enlarged view of the electromagnetic 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 chamber 25 of the negative pressure booster 2 to the constant pressure chamber 12 or the atmosphere is airtightly arranged on the front surface of the housing 10. It is installed.
[0019]
The valve housing 28a of the electromagnetic valve device 28 includes therein a constant pressure port 28b communicating with the constant pressure chamber 12, an atmospheric port 28c communicating with the air cleaner for introducing air, a variable pressure port 28d connected to the atmospheric passage 27, and the constant pressure chamber 12 and auxiliary. A constant pressure valve seat 28e communicating with the variable pressure chamber 25, an atmospheric valve seat 28f communicating the atmosphere with the auxiliary variable pressure chamber 25, a valve body portion 28h having a valve 28g as a valve body at the tip, a movable core 28i, It has a rod portion 28j that can come into contact with the movable core 28i on one end (left end) side, and a solenoid 28k.
[0020]
The solenoid 28k is connected to a power source of a vehicle (not shown) through a terminal 28l, and is operated by being supplied with electric power from the power source by a controller of the vehicle (not shown).
[0021]
2, the valve 28g is in a non-engagement state with the constant pressure valve seat 28e, so that the auxiliary variable pressure chamber 25 is located inside the atmosphere introduction passage 27, the variable pressure port 28d, the valve 28g and the constant pressure valve. It communicates with the constant pressure chamber 12 through a gap with the seat 28e and a constant pressure port 28b.
[0022]
On the other hand, as described above, when electric power is supplied to the solenoid 28k by the vehicle controller (not shown), the solenoid 28k operates the suction of the movable core 28i, and the movable core 28i slides to the right in FIG. The movable core 28i presses the rod portion 28j, and the movable core 28i and the rod portion 28j integrally move toward the right in FIG.
[0023]
The right end portion of the rod portion 28j urged by the movable core 28i contacts the left end portion of the valve body portion 28h, and the rod portion 28j presses the valve body portion 28h toward the right side in FIG. The valve 28g abuts on the constant pressure valve seat 28e and the atmospheric valve seat 28f is disengaged.
[0024]
Therefore, the auxiliary variable pressure chamber 25 is not shown in the figure through the inside of the atmosphere introduction passage 27, the gap between the transformation port 28h, the valve 28g and the atmosphere valve seat 28f, the communication hole, the atmosphere port 28c, and the air cleaner for introducing the atmosphere. Air is introduced from the interior space of the vehicle.
[0025]
An ABS (anti-lock brake system) 4 in FIG. 1 includes therein a hydraulic line through which brake fluid flows, an electromagnetic valve device that blocks the flow of brake fluid in the hydraulic line, and a reservoir in which brake fluid is stored. And a pump unit for sucking and discharging the brake fluid.
[0026]
The master cylinder 3 and the ABS (anti-lock brake system) 4 normally act on the wheels FR, FL, RR, FL via the hydraulic pressure according to the output from the output rod 19, and the speed of the vehicle body and the wheel When the speed difference increases, the braking force is temporarily reduced to prevent the wheel from slipping. The ABS (anti-lock brake system) 4 is electrically connected to the electronic control unit 32.
[0027]
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. The stroke sensor 29 and the brake switch 30 are electrically connected to the electronic control device 32, respectively.
[0028]
As shown in FIG. 3, the electronic control device 32 includes a microcomputer 39 including a CPU 33, a ROM 34, a RAM 35, a timer 36, an input port 37, and an output port 38 connected to each other via a bus. The output signals of the stroke sensor 29, the brake switch 30, and the temperature sensor 31 are configured to be input from the input port 37 to the CPU 33 via the amplifier circuits 40a to 40c, respectively. A control signal is output from the output port 38 to the solenoid 28k via a solenoid drive circuit 41 as an automatic braking process control means, and also controlled to an ABS (anti-lock brake system) 4 via a braking force control circuit 42. A signal is output. In the microcomputer 39, the ROM 34 stores a program corresponding to each flowchart 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. The RAM 35 temporarily stores variable data necessary for executing the program.
[0029]
Next, the operation of the automotive brake fluid pressure control apparatus 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 to the brake pedal 15, and FIG. FIG. 6 is a flowchart of threshold correction, and FIG. 7 is a correlation diagram between the air temperature and the threshold correction ratio of the present embodiment. When the driver operates the brake pedal 15 which is a brake operation member of the vehicle, the input rod 16 connected to the brake pedal 15 receives the brake operation force and moves to the left in FIG. Therefore, the input member 17 fixed to the input rod 16 also moves integrally with the input rod 16 to the left in FIG.
[0030]
When the brake pedal 15 is operated, the brake switch 30 transmits an ON signal to the electronic control device 32 to light the brake light.
[0031]
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, and eventually the seal portion 21a moves to the vacuum valve valve seat 14a of the power piston 14. Since the abutting chamber 13 is cut off from the constant pressure chamber 12, the communication with the negative pressure source of the vehicle is also cut off.
[0032]
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. Therefore, an atmospheric pressure difference is generated between the constant pressure chamber 12 and the variable pressure chamber 13 due to the inflow of air into the variable pressure chamber 13, and therefore the movable wall 11 that receives a load due to the atmospheric pressure difference and the power piston 14 connected thereto. However, the output rod 19 is pressed to the left via the reaction disk 18.
[0033]
When the output rod 19 is pushed and moved to the left, the power piston 14 outputs the amplified braking force to the output rod 19.
[0034]
When a braking force is output to the output rod 19 and 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 flows through the ABS (anti-lock brake system) 4 to the wheel cylinder. The braking force is applied to the wheels FR, FL, RR, RL of the vehicle. In other words, in the present embodiment, the negative pressure booster 2, the master cylinder 3, and the ABS 4 constitute first braking force generation means.
[0035]
In this normal operating state, since the solenoid 28k is inactive, the auxiliary variable pressure chamber 25 communicates with the constant pressure chamber 12, there is no pressure difference before and after the auxiliary movable wall 23, and the auxiliary movable wall 23 is inoperative. It is in a state. The relationship between the brake operation force acting on the brake pedal 15 and the brake output acting on the output rod 19 at this time is shown by a line A in FIG.
[0036]
On the other hand, wheel speeds of the wheels FR, FL, RR, and RL are detected by a wheel speed sensor (not shown), and an ABS (anti-lock brake system) 4 is driven according to the detection output of the wheel speed sensor and supplied to the wheel cylinder. The brake fluid pressure is controlled to appropriately control the braking force for the wheels FR, FL, RR, and RL.
[0037]
When the depression of the brake pedal 15 is released, the input rod 16 moves toward the outside of the power piston 14, the valve plunger 17 slides in the power piston 14 with the movement of the input rod 16, and the air valve valve seat 17a is moved. Contact with the seal portion 20a blocks the communication between the variable pressure chamber 13 and the atmosphere, and 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 the vacuum valve valve seat 14a. The constant pressure chamber 12 and the variable pressure chamber 13 are communicated 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 power piston 14 returns to the initial position. As the power piston 14 returns 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 to 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 transmits an OFF signal to the electronic control device 32 and stops the lighting of the brake light.
[0038]
Next, the operation of the automobile brake fluid pressure control apparatus 1 in which the threshold correction and the automatic braking process are 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 execution of the program is started, the electronic control unit 32 performs initial setting and initial check in steps 101 and 102 and the ABS control program. Thereafter, the main routine of steps 104 to 111 or 112 is executed at a constant period (6 ms) checked by the timer 36 in step 103.
[0039]
In step 104, the electronic control unit 32 takes in various input data from the stroke sensor 29, the brake switch 30, the temperature sensor 31, the timer 41, and the like.
[0040]
In step 105, the depression amount ST0 (mm) of the brake pedal 15 from the stroke sensor 29, the depression amount ST1 (mm) of the brake pedal 15 detected one cycle before (6 ms) in the main routine, and one of the main routine Based on the time required for the cycle (6 ms), the brake pedal depression speed Vp0 (mm / sec) is calculated. That is, the depression amount ST1 of the brake pedal 15 detected one cycle before (6 ms) in the main routine from the depression amount ST0 of the brake pedal 15 from the stroke sensor 29 detected when the brake pedal 15 is depressed. The brake pedal depression speed Vp0 is calculated by dividing the difference between ST0 and ST1 by 6 ms, which is the time required for one cycle of the main routine.
[0041]
In step 106, failure detection of each sensor or the like is performed.
[0042]
Next, in step 107, a threshold value TH (mm / sec), which will be described later, is corrected.
[0043]
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.
[0044]
In step 110, it is determined whether a start condition for the automatic braking process is satisfied. In the present embodiment, the brake switch 30 transmits an ON signal, and the brake pedal depression speed Vp0 calculated in step 105 is compared with the threshold value TH of the brake pedal depression speed corrected in step 107. If the depression speed Vp0 is equal to or higher than the brake pedal depression speed threshold TH, it is determined that the operation of the brake pedal 15 is a sudden braking operation, and the process proceeds to step 112. If not, the depression of the brake pedal 17 is performed. Is determined to be a normal brake operation, the automatic braking process is not performed, and the process returns to step 103.
[0045]
In step 112, the solenoid 28k is driven by sending a signal to the solenoid drive circuit 41 to drive the solenoid 28k to perform the automatic braking process.
[0046]
When the solenoid 28k is driven, the movable core 28k is moved rightward in FIG. 2 against the biasing force of the spring.
[0047]
As described above, since the atmosphere is introduced into the auxiliary variable pressure chamber 25 by the movement of the movable core 28k, a pressure difference is generated before and after the auxiliary movable wall 23, and the auxiliary movable wall 23 is moved to the left in FIG. .
[0048]
As the auxiliary movable wall 23 moves, the inner peripheral portion of the auxiliary movable wall 23 engages with the outer peripheral portion of the flange portion of the second output rod 192, and only the second output rod 192 is loaded leftward in FIG. Add and move.
[0049]
Since the load applied to the second output rod 192 does not act on the reaction disk 18, it does not react with the input member 17 but is purely increased as a brake output.
[0050]
Due to the movement of the second output rod 192, the master cylinder 3 increases the hydraulic pressure and brakes the wheels FR, FL, RR, RL of the vehicle via the ABS (anti-anti-lock brake system) 4. The ABS (anti-anti-lock brake system) 4 is actuated as necessary.
[0051]
By introducing the atmosphere into the auxiliary variable pressure chamber 25, the brake output acting on the output rod 19 is increased by a certain amount with respect to the same brake operation force acting on the brake pedal 15 as compared with when the pressure in the auxiliary variable pressure chamber 25 is negative. The relationship between the brake operation force acting on the brake pedal 15 and the brake output acting on the output rod 19 at this time is shown by a line B in FIG. That is, an automatic braking process is performed in which a larger braking pressure resulting from the brake pedal position is automatically established. That is, in the present embodiment, the solenoid 28k is actuated from the negative pressure booster 2, the master cylinder 3, and the ABS (anti-anti-lock brake system) 4, so that an additional braking force is exhibited. Two braking force generating means are configured.
[0052]
When the automatic braking process is performed, the process returns from step 112 to step 103 and proceeds to step 108 via steps 104, 105, 106, and 107. Since the automatic braking process is performed in step 108, step 109 is performed. Proceed to
[0053]
In step 109, it is determined whether or not an automatic braking process termination condition is 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 an OFF signal, the process proceeds to step 111; Return to step 103.
[0054]
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 to the right together with the input rod 16 as the input rod 16 moves backward. The seal portion 21a of the control valve 21 is engaged with the input member 17, and the seal 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 and communicated with the constant pressure chamber 12, so Since the degree of negative pressure in the chamber 13 increases, the assisting force to the power piston 14 also decreases, and the reaction force from the master cylinder 3 and the return spring 26 in the booster make the power piston 14 and the input rod 16 in FIG. It is moved to the right and the return process is completed by releasing the input. On the other hand, as the brake pedal 15 returns to the initial position, the brake switch 29 transmits an OFF signal to the electronic control device 32.
[0055]
In step 109, when the electronic control unit 32 receives the OFF signal of the brake switch 30, the drive of the solenoid 28k is released and the automatic braking process is terminated. That is, when the drive 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 to the left in FIG. 2 by the biasing force of the spring via the rod portion 28j. Returned to In addition, the valve body portion 28h is urged to the left in FIG. 2 by the urging force of the spring, and the valve 28g is separated from the constant pressure valve seat 28e and is brought into contact with the atmospheric valve seat 28f.
[0056]
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 communicated with the constant pressure chamber 12 again, and the auxiliary movable wall 23 is directed to the initial position by the return spring 26. Thus, 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 releases the brakes of the vehicle wheels FR, FL, RR, and RL. That is, the automatic braking process is terminated.
[0057]
The correction of the threshold value Vpt in step 107 is performed by executing the flowchart shown in FIG.
[0058]
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 lower than the set temperature T, the current temperature is determined to be a low temperature and the process proceeds to step 202; otherwise, the temperature is determined to be a high temperature and the process proceeds to step 204.
[0059]
Next, in step 202, first, a threshold correction ratio K is calculated from the temperature x based on a regression equation of K = A × (x−T) +1 shown as the correlation characteristic line a in FIG. A in the regression equation of the correlation characteristic line a indicates a characteristic coefficient, which 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. Next, based on the regression equation represented by TH = TH0 × K, the threshold TH0 is reduced to a low temperature by multiplying the previously calculated threshold correction ratio K by a preset ideal threshold TH0. It is corrected to an appropriate threshold value TH.
[0060]
In step 203, first, a threshold correction ratio K is calculated from the temperature x based on the regression equation of K = B × (x−T) +1 shown as the correlation characteristic line b in FIG. B in the regression equation of the correlation characteristic line b represents 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. Next, based on the regression equation represented by TH = TH0 × K, the threshold value TH0 is increased to a high temperature by multiplying the previously calculated threshold value correction ratio K by a preset ideal threshold value TH0. It is corrected to an appropriate threshold value TH.
[0061]
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 air temperature is low, the flow rate of the hydraulic fluid decreases with a change in the viscosity of the hydraulic fluid in the brake fluid pressure control device 1 for an automobile, and consequently, the operation 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 braking operation in response to a decrease in the operating speed of the brake pedal 15. Conversely, when the air temperature is high, the flow rate of the hydraulic fluid increases with the change in the viscosity of the hydraulic fluid in the brake fluid pressure control device 1 for an automobile, and the operation speed of the brake pedal 15 is also increased. However, when the temperature is high, the threshold value is corrected to be high, so that an increase in the operation speed of the brake pedal 15 can be dealt with and a sudden brake operation can be reliably detected.
[0062]
Therefore, it is possible to provide the automobile brake fluid pressure control device 1 that can set an effective threshold even when the viscosity of the hydraulic fluid changes.
[0063]
In the present embodiment, 10 ° C. is used as the set temperature when determining the low temperature and the high temperature, but it goes without saying that the present invention is not particularly limited to this. In this embodiment, K = A × (x−T) +1 and K = B × (x−T) +1 are used for calculating the correction ratio K. However, the present invention is particularly limited to this. It goes without saying that it is not.
[0064]
In the present embodiment, the threshold value is corrected based on the formula TH = TH0 × K. Needless to say, the threshold value is not limited to this.
[0065]
In the present embodiment, the depression amount of the brake pedal 15 is detected directly from the brake pedal 15 to detect the depression amount of the brake pedal 15, but it goes without saying that the present invention is not limited to this configuration.
[0066]
Further, in the present embodiment, the automatic braking process is performed by increasing the braking action generated from the brake pedal position by operating the boosting action by supplying power to the solenoid 28k in the negative pressure booster 2 and driving it. The pressure is automatically established. For example, ABS (anti-static control device) having a pump unit capable of independently applying a hydraulic pressure to each wheel cylinder of the wheels FR, FL, RR, and RL. The brake for an automobile according to the present invention automatically establishes a larger braking pressure resulting from the brake pedal position by applying a braking force to the wheels by operating the pump unit using a lock brake system). Similar effects can be obtained in the apparatus.
[0067]
Further, in the present embodiment, the braking force generating means includes the negative pressure booster 2, the master cylinder 3, and the ABS (anti-skid control system) 4, but this is particularly limited to this configuration. Needless to say, the configuration of the negative pressure booster 2 is not limited to the above configuration. 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.
[0068]
In the present embodiment, the brake pedal depression speed Vp0 is used as an amount related to the operation speed of the brake operation member. However, the present invention is not limited to this, for example, an amount related to the operation speed of the brake operation member. A similar effect can be obtained also in the automobile braking device of the present invention using the pressure increase rate of the master cylinder pressure.
[0069]
Further, in the present embodiment, the depression amount ST0 (mm) of the brake pedal 15 from the stroke sensor 29 and the depression amount ST1 (mm) of the brake pedal 15 detected one cycle before (6 ms) in the main routine. The brake pedal depression speed Vp0 (mm / sec) is calculated based on the time required for one cycle of the main routine (6 ms), but it goes without saying that the present invention is not limited to a specific configuration.
[0070]
As mentioned above, although this invention was demonstrated according to the said embodiment, this invention is not limited only to the said aspect, Various aspects based on the principle of this invention are included.
[0071]
【The invention's effect】
As explained above, according to the present invention, Since the threshold relating to the operation speed of the brake operation member is configured to be corrected low when the temperature is low and high when the temperature is high, It is possible to provide an automotive brake fluid pressure control device capable of setting an effective threshold even when the viscosity of the hydraulic fluid changes.
[Brief description of the drawings]
FIG. 1 is a configuration diagram of a brake fluid pressure control apparatus 1 for an automobile according to the present embodiment.
2 is a partially enlarged cross-sectional view of the negative pressure booster 2 in FIG. 1;
3 is a block diagram showing a configuration of an electronic control device 32 in FIG. 1. FIG.
FIG. 4 is a characteristic diagram of the negative pressure booster 2 of the present embodiment.
FIG. 5 is a flowchart of an automatic braking process according to the present embodiment.
FIG. 6 is a flowchart of threshold correction according to the present embodiment.
FIG. 7 is a regression diagram regarding the temperature and the threshold correction ratio according to the present embodiment.
[Explanation of symbols]
1 Automotive brake fluid pressure control device
2 Negative pressure booster
3 Master cylinder
4 ABS
15 Brake pedal
30 Stroke sensor
31 Air temperature sensor
32 Electronic control unit
FR, FL, RR, RL wheel

Claims (1)

A brake operating member and first braking force generating means for applying a first braking force to the wheel by pressing and urging the hydraulic fluid toward the wheel by the brake operating member when the brake operating member is operated. A second braking force generating means for adding a second braking force to the first braking force, an operating speed detecting means for detecting an amount related to the operating speed of the brake operating member, and a detection result of the operating speed detecting means, Comparing means for comparing the threshold value, control means for operating the second braking force generating means when the operating speed of the brake operating member is equal to or higher than the threshold value based on the comparison result of the comparing means, and detecting the temperature and temperature detecting means, said threshold value, when has been a high temperature detected by said temperature detecting means together with the temperature detected by said temperature detecting means to correct low when low Automotive brake fluid pressure control apparatus that includes a high correction correcting means.

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