JP4421854B2 - Anti-lock brake control device for vehicle - Google Patents

Description

  The present invention relates to a pressure increasing state in which the generated hydraulic pressure of the brake hydraulic pressure generating means for generating the brake hydraulic pressure corresponding to the brake operation amount is applied to the wheel brake, a holding state in which the brake hydraulic pressure of the wheel brake is maintained, and a wheel brake Pressure regulating valve means that can regulate the brake fluid pressure of the wheel brake by switching the decompression state to release the brake fluid pressure, and the above-mentioned regulation so that the target pressure increase amount obtained by the feedback calculation of the previous pressure increase amount at the time of pressure increase. The present invention relates to an antilock brake control device for a vehicle comprising a control unit for controlling the operation of a pressure valve means.

For example, Japanese Patent Application Laid-Open No. H10-228561 has already known that when the pressure is increased in the antilock brake control state, the pressure increase amount at the previous pressure increase is fed back to determine the current pressure increase amount.
JP-A-7-117648

  By the way, when anti-lock brake control is being executed, if the friction coefficient of the road surface changes from low to high, or if the brake pedal is re-applied to the side where the brake force is increased after the brake force is once released, the pressure increases. In general, the operation of the pressure regulating valve means is controlled so that the amount increases, and if the target pressure increase amount is determined by feedback even during such a change in the friction coefficient or a reapplying operation, the friction coefficient There is a possibility that the amount of pressure increase after the change or after the re-applying operation becomes too large, resulting in a decrease in brake feeling.

  The present invention has been made in view of such circumstances. After the friction coefficient is changed from low to high, or after re-braking operation to increase the braking force after the braking force is once relaxed, the amount of pressure increase is increased. An object of the present invention is to provide an anti-lock brake control device for a vehicle that avoids an excessive increase in the vehicle speed and can obtain a good brake feeling.

In order to achieve the above object, the invention according to claim 1 is a pressure-increasing state in which the generated hydraulic pressure of the brake hydraulic pressure generating means for generating the brake hydraulic pressure corresponding to the brake operation amount is applied to the wheel brake. Pressure control means that can adjust the brake fluid pressure of the wheel brake by switching the holding state that holds the brake fluid pressure and the reduced pressure state that releases the brake fluid pressure of the wheel brake, and at the time of pressure increase, it is obtained by feedback calculation of the previous pressure increase amount and the anti-lock brake control apparatus for a vehicle and a control unit so as to achieve the target pressure increase amount for controlling the operation of the pressure regulating valve unit, the control unit, the friction coefficient of the run line road surface changes from low to high and targeted pressure increase amount of feedback operation prohibition time constant as well as prohibiting the feedback calculation of the target pressure increase amount when the previous SL coefficient of friction Characterized in that to resume the first feedback calculation of the target pressure increase amount from the pressure increasing state after a vacuum state after the change from its initial value to a constant target pressure increase amount was determined during the feedback operation prohibition as an initial value And

In order to achieve the above object, the invention according to claim 2 is a pressure increasing state in which the generated hydraulic pressure of the brake hydraulic pressure generating means for generating the brake hydraulic pressure corresponding to the brake operation amount is applied to the wheel brake, the wheel brake Pressure control valve means that can adjust the brake fluid pressure of the wheel brake by switching the holding state that maintains the brake fluid pressure of the wheel brake and the pressure reduction state that releases the brake fluid pressure of the wheel brake, in the anti-lock brake control apparatus for a vehicle and a control unit which obtained as the target pressure increase amount for controlling the operation of the pressure regulating valve unit, the control unit temporarily loosen the brake force during the braking operation feed with prohibits feedback calculation of the target pressure increase amount when re brake operation on the side of increasing the braking force after It defines Tsu target pressure increase amount of the click operation prohibition time constant, the feedback calculation of the target pressure increase amount from the pressure increasing state after a first reduced pressure after re braking operation, a constant that defines the time of the feedback operation prohibition The target pressure increase amount is taken as an initial value and restarted from the initial value.

According to the first aspect of the invention, when the friction coefficient of the traveling road surface changes from low to high during execution of the antilock brake control, feedback of the pressure increase amount is prohibited and the target pressure increase amount when the feedback calculation is prohibited , And then the feedback calculation of the target pressure increase amount is restarted from the initial value with the target pressure increase amount set when the feedback calculation is prohibited as the initial value. It is possible to avoid an excessive increase in pressure increase after increasing the pressure and obtain a good brake feeling.

According to the second aspect of the present invention, when the brake force is once released during the antilock brake control and then re-brake operation is performed to increase the brake force, the feedback of the pressure increase amount is prohibited and the feedback calculation is prohibited. The target pressure increase amount at the time is set constant, and then the feedback calculation of the target pressure increase amount is restarted from the initial value with the target pressure increase amount set when the feedback calculation is prohibited as the initial value. Correspondingly, the pressure increase amount can be prevented from becoming too large after the pressure increase amount is increased, and a good brake feeling can be obtained.

  DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below based on one embodiment of the present invention shown in the accompanying drawings.

  FIGS. 1 to 5 show an embodiment of the present invention, FIG. 1 is a hydraulic circuit diagram of a motorcycle brake device, FIG. 2 is a flowchart showing a processing procedure during pressure increase control, and FIG. 4 is a flowchart showing a subroutine for flag setting processing in the flowchart of FIG. 2, FIG. 4 is a timing chart when the friction coefficient changes from low to high during antilock brake control, and FIG. 5 is a brake reapplying during antilock brake control. It is a timing chart when operation was made.

  First, in FIG. 1, a scooter type motorcycle is equipped with first and second master cylinders MA and MB as brake fluid pressure generating means, and the first master cylinder MA is a right that is operated by the occupant with the right hand. The hydraulic pressure is output according to the operation of the brake lever 1, and the second master cylinder MB outputs the hydraulic pressure according to the operation of the left brake lever 2 operated by the occupant with the left hand.

  On the other hand, a front wheel brake BF having a pair of pods 3 and 4 is mounted on a front wheel which is a non-drive wheel, and the first master cylinder MA has a pressure regulating valve means 6A on the front wheel brake BF. And the second master cylinder MB is connected via the pressure regulating valve means 6B1 and the delay valve 5. The second master cylinder MB is connected to the rear wheel brake BR mounted on the rear wheel, which is the driving wheel, via the pressure regulating valve means 6B2.

  The pressure regulating valve means 6A includes a normally open solenoid valve 7 provided between the pod 3 of the front wheel brake BF and the first master cylinder MA, a check valve 8 connected in parallel to the normally open solenoid valve 7, It is composed of a normally closed electromagnetic valve 9 provided between the pod 3 of the front wheel brake BF and the reservoir 10A. The communication between the first master cylinder MA and the pod 3 of the front wheel brake BF is interrupted. The communication between the pod 3 of the front wheel brake BF and the reservoir 10A can be switched.

  A suction side of a return pump 11A that pumps up the brake fluid of the reservoir 10A and pumps it to the first master cylinder MA side is connected to the reservoir 10A via a suction valve 12A. The discharge side of the return pump 11A is It is connected to the first master cylinder MA via the discharge valve 13A, the damper 14A and the orifice 15A.

  Like the pressure regulating valve means 6A, the pressure regulating valve means 6B1 is composed of a normally open solenoid valve 7, a check valve 8, and a normally closed solenoid valve 9, and is connected to the pod 4 of the front wheel brake BF. It is possible to switch between communication / blocking between the delay valve 5 and the second master cylinder MB and communication / blocking between the delay valve 5 and the reservoir 10B.

  Similarly to the pressure regulating valve means 6A, 6B1, the pressure regulating valve means 6B2 is composed of a normally open type electromagnetic valve 7, a check valve 8 and a normally closed type electromagnetic valve 9, and a rear wheel brake BR and a The communication / blocking between the two master cylinders MB and the communication / blocking between the rear wheel brake BR and the reservoir 10B can be switched.

  A suction side of a return pump 11B that pumps up the brake fluid of the reservoir 10B and pumps it to the second master cylinder MB side is connected to the reservoir 10B via a suction valve 12B. The discharge side of the return pump 11B is It is connected to the second master cylinder MB via the discharge valve 13B, the damper 14B and the orifice 15B.

  A common single motor 16 is connected to the both return pumps 11A and 11B, and the both return pumps 11A and 11B are driven by the motor 16.

  The deenergization / energization of the normally open solenoid valve 7... And the normally closed solenoid valve 9... And the operation of the motor 16 in each pressure regulating valve means 6A, 6B1, 6B2 individually detect the wheel speeds of the front wheels and the rear wheels. It is controlled by a control unit 18 to which detection signals of front wheel and rear wheel speed sensors 19F and 19R are input. The control unit 18 detects detected values of front wheel and rear wheel speed sensors 19F and 19R. Based on the control, the operation of each pressure regulating valve means 6A, 6B1, 6B2 is controlled so as to repeat the brake fluid pressure reducing, holding, and pressure increasing cycle. Anti-lock brake control for the front and rear wheel brakes BF and BR is executed.

  The motor 16 that drives the pair of return pumps 11A and 11B in common starts operation in response to the start of the antilock brake control, and the brake fluid released to the reservoirs 10A and 10B is returned to the return pumps 11A and 11B. 11B is returned to the first and second master cylinders MA and MB. Accordingly, the amount of operation of the brake levers 1 and 2 in the first and second master cylinders MA and MB is not increased by the amount released to the reservoirs 10A and 10B. Further, the control unit 18 starts the operation of the motor 16 with the start of the antilock brake control by any one of the pressure regulating valve means 6A, 6B1, 6B2.

  Thus, when the brake fluid pressure is reduced during the anti-lock brake control, the control unit 18 energizes the normally open solenoid valve corresponding to the wheel that is about to enter the locked state among the normally open solenoid valves 7. While the valve is closed, the normally closed solenoid valve corresponding to the wheel among the normally closed solenoid valves 9 is opened by energization. Then, a part of the brake fluid pressure is released to the reservoir 10A or 10B and is reduced. When holding the brake fluid pressure, the control unit 18 closes the normally open solenoid valves 7 by energization and keeps the normally closed solenoid valves 9 closed by deenergization. Further, when the brake fluid pressure is increased, the control unit 18 opens the normally open solenoid valves 7... When not energized and keeps the normally closed solenoid valves 9. And a pulse pressure increase which repeatedly repeats the normally open solenoid valve 7 by energization and the normally closed solenoid valve 9 by non-energization and the non-pulse output state in which the valve is closed. Moreover, at the time of the pulse pressure increase, the duty ratio can be changed by changing the time of the pulse output state in one cycle, whereby the pressure increase amount can be changed.

  Further, the control unit 18 executes the pressure increase control according to the procedure shown in FIG. 2, but in step S1, the flag setting process by the subroutine shown in FIG. 3 is executed. In step S11 of FIG. 3, it is determined whether or not the friction coefficient (μ) has changed from low to high, for example, based on whether or not the estimated vehicle body deceleration has changed significantly, and the friction coefficient has changed from low to high. If it is determined, the flag F1 is set to “1” in step S12, and the process proceeds to step S13.

  In step S13, whether or not a re-brake operation, that is, a re-apply operation to increase the brake force after the brake force is once relaxed in the middle of the brake operation is performed, for example, a change in the hydraulic pressure output of the master cylinders MA and MB If it is determined that the redemption operation has been performed, the flag F2 is set to “1” in step S14, and the process proceeds to step S15.

  In step S15, it is determined whether or not the flag F1 is “1”. If the flag F1 is “0”, the process proceeds to step S16 to determine whether or not the flag F2 is “1”. Thus, when it is confirmed in steps S15 and S16 that either of the flags F1 and F2 is “1”, the process proceeds to step S17 to determine whether or not the pressure is reduced, and confirms that the pressure is reduced. If so, the flags F1 and F2 are reset in step S18.

  According to such flag setting processing, when the friction coefficient of the traveling road surface changes from low to high, the flag F1 becomes “1” from the time when the friction coefficient changes until the first pressure reduction state is reached after the change, and the brake operation is performed. When the brake force is once released in the middle of the operation and then re-brake operation is performed to increase the brake force, the flag F2 is set to “1” from the time of the re-brake operation until the first decompression state after the re-brake operation.

Referring again to FIG. 2, in step S2 after the flag setting process, a target pressure increase amount calculation process by feedback is executed to determine the target pressure increase amount at the current pressure increase by feedback of the pressure increase amount at the previous pressure increase. The

  In step S3, it is determined whether or not the flag F1 is “1”. When the flag F1 is “1”, the target pressure increase amount obtained in step S2 is cleared in step S4, and in step S5 thereafter. The target pressure increase amount corresponding to when the friction coefficient of the traveling road surface changes from low to high is calculated so that the pressure increase amount gradually increases with time, for example.

  When it is determined in step S3 that the flag F1 is “0”, the process proceeds to step S6 to determine whether or not the flag F2 is “1”, and when the flag F2 is “1”, in step S2. The obtained target pressure increase amount is cleared in step S7, and in subsequent step S8, the target pressure increase amount corresponding to the case where the brake force is once released in the middle of the brake operation and then re-brake operation is performed to increase the brake force. Is calculated as, for example, a maximum fixed amount.

  Thus, when it is determined in step S6 that the flag F2 is “0”, and after the processing in step S8, in step S9, the pressure increasing process is executed so that the target pressure increasing amount is obtained. .

  According to such pressure increase processing, the control unit 18 basically determines the target pressure increase amount at the current pressure increase by feedback during the pressure increase control, but the friction coefficient of the running road surface is low. When the pressure changes to high, feedback calculation of the target pressure increase amount is prohibited, and feedback of the target pressure increase amount is resumed from the pressure increase state after the first pressure reduction state after the change of the friction coefficient. If the brake force is once released in the middle of the operation and then re-brake to the side where the brake force is increased, feedback calculation of the target pressure increase amount is prohibited, and the pressure increase state after the first pressure reduction state after the re-brake operation is The feedback calculation of the pressure increase amount is resumed.

  Next, the operation of this embodiment will be described. For example, during the antilock brake control of the front wheels, the control mode, the wheel speed of the front wheels, the estimated vehicle body speed, the pressure increase pulse, the target pressure increase amount, and the brake fluid pressure of the front wheels are shown in FIG. Assuming the case of a change as shown in FIG. 5, the feedback calculation of the target pressure increase amount is prohibited at the time t1 when the flag F1 rises, that is, at the time t1 when the friction coefficient of the traveling road surface changes from low to high. When the first pressure reduction state after the change of the friction coefficient occurs at time t2, the flag F1 falls, and the target pressure is increased according to the first pressure increase state after the fall of the flag F1 occurs at time t3. The feedback calculation of the pressure increase amount is resumed.

Thus, when the flag F1 is set, the target pressure increase amount is set so that the pressure increase amount gradually increases with time, for example, in order to cope with the change in the friction coefficient of the traveling road surface from low to high. However , after that , the feedback calculation of the target pressure increase amount will be resumed with the constant target pressure increase amount set at the time of the feedback calculation prohibition as the initial value. It is possible to avoid an excessive increase in the pressure increase amount after the friction coefficient of the traveling road surface changes from low to high, and to obtain a good brake feeling.

  Also, assuming that the control mode, the front wheel speed, the estimated vehicle speed, the pressure boosting pulse, the target pressure increase amount, and the front wheel brake fluid pressure change as shown in FIG. At time t4 when the flag F2 rises, that is, at time t4 when the brake force is once released in the middle of the brake operation and then re-brake operation is performed to increase the brake force, the feedback calculation of the target pressure increase amount is prohibited. When the first pressure reduction state after the re-brake operation occurs at time t5, the flag F2 falls, and the target pressure increases as the first pressure increase state after the flag F2 falls occurs at time t6. The pressure feedback calculation is resumed.

Thus, in the state in which the flag F2 is set, the pressure increase amount is, for example, a certain maximum value in order to cope with a case where the brake force is once relaxed in the middle of the brake operation and then re-brake operation is performed to increase the brake force. The target pressure increase amount is determined to be constant so that the feedback calculation of the target pressure increase amount is resumed with the constant target pressure increase amount determined when the feedback calculation is prohibited as the initial value thereafter. Therefore, after releasing the braking force once during anti-lock braking control and then re-braking to the side where the braking force is increased, the pressure increase amount is prevented from becoming too large, and a good brake feeling is obtained. be able to.

  Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various design changes can be made without departing from the present invention described in the claims. It is.

  For example, in the above embodiment, the case where the present invention is applied to a motorcycle has been described, but the present invention can also be applied to a four-wheeled vehicle.

1 is a hydraulic circuit diagram of a motorcycle brake device. FIG. It is a flowchart which shows the process sequence at the time of pressure increase control. It is a flowchart which shows the subroutine for the flag setting process in the flowchart of FIG. It is a timing chart when a friction coefficient changes from low to high at the time of anti-lock brake control. It is a timing chart when the brake re-applying operation was made at the time of anti-lock brake control.

6A, 6B1, 6B2 ... Pressure regulating valve means 18 ... Control unit BF, BR ... Wheel brake MA, MB ... Master cylinder as brake fluid pressure generating means

Claims (2)

The brake fluid pressure generating means (MA, MB) for generating the brake fluid pressure corresponding to the brake operation amount is applied to the wheel brakes (BF, BR), and the wheel brakes (BF, BR) are braked. Pressure regulating valve means (6A, 6B1, which can regulate the brake fluid pressure of the wheel brakes (BF, BR) by switching the holding state for retaining the fluid pressure and the reduced pressure state for releasing the brake fluid pressure of the wheel brakes (BF, BR) 6B2) and a control unit (18) for controlling the operation of the pressure regulating valve means (6A, 6B1, 6B2) so that the target pressure increase amount obtained by the feedback calculation of the previous pressure increase amount at the time of pressure increase is provided. in the anti-lock brake control apparatus for a vehicle, said control unit (18) is run feedback target pressure increase amount when the friction coefficient of the line road is changed from low to high Targeted pressure increase amount when the feedback operation prohibition constant while prohibiting operation, the feedback calculation of the target pressure increase amount from the pressure increasing state after a first vacuum state after the change before Symbol friction coefficient, the feedback antilock brake control apparatus for a vehicle, characterized in that resumes from its initial value to a constant target pressure increase amount as defined in operation prohibition time as the initial value. The brake fluid pressure generating means (MA, MB) for generating the brake fluid pressure corresponding to the brake operation amount is applied to the wheel brakes (BF, BR), and the wheel brakes (BF, BR) are braked. Pressure regulating valve means (6A, 6B1, which can regulate the brake fluid pressure of the wheel brakes (BF, BR) by switching the holding state for retaining the fluid pressure and the reduced pressure state for releasing the brake fluid pressure of the wheel brakes (BF, BR) 6B2) and a control unit (18) for controlling the operation of the pressure regulating valve means (6A, 6B1, 6B2) so that the target pressure increase amount obtained by the feedback calculation of the previous pressure increase amount at the time of pressure increase is provided. in the anti-lock brake control apparatus for a vehicle, said control unit (18), on the side of increasing the braking force after loosening once the braking force during the braking operation Target pressure increase amount from the pressure increasing state after targeted pressure increase amount of feedback operation prohibition time constant as well as prohibiting the feedback calculation of the target pressure increase amount was the first reduced pressure after re brake operation when the brake operating The vehicle anti-lock brake control apparatus restarts the feedback calculation from the initial value with a constant target pressure increase amount determined when the feedback calculation is prohibited as an initial value.

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