Vehicle brake control device

Abstract

This vehicle brake control device is provided with a control unit for controlling a braking force of a wheel brake on the basis of an operation amount of a brake operating element. If the operation amount (operation angle θ) of the brake operating element drops to or below a first prescribed value θth1, the control unit starts a release determination (S6, S7) for determining whether the brake operating element has been slackened, and if the operation amount is decreasing from the first prescribed value θth1 during the release determination (S6: Yes), it is determined that the brake operating element has been slackened (S7).

Description

[Technical Field]

[0001] The present invention relates to a brake control device for a vehicle, and more particularly to a brake control device for a two-wheeled vehicle. [Background technology]

[0002] BACKGROUND ART Conventionally, a vehicle brake control device is known that performs a release determination to determine whether a brake lever has been released based on wheel cylinder pressure detected by a pressure sensor (see Japanese Patent Application Laid-Open No. 2008-195138). Summary of the Invention

[0003] However, a vehicle brake control device that does not have a pressure sensor cannot perform the release determination as in the conventional case.

[0004] SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a vehicle brake control device that is not equipped with a pressure sensor, and that can accurately determine whether a brake operator has been released.

[0005] In order to solve the above-mentioned problems, a vehicle brake control device according to the present invention includes a control unit that controls the braking force of a wheel brake based on the operation amount of a brake operator. The control unit starts a release determination to determine whether the brake operator has been released when the amount of operation of the brake operator becomes equal to or less than a first predetermined value, and determines that the brake operator has been released if the amount of operation decreases from the first predetermined value during the release determination.

[0006] According to this configuration, the release determination is made based on the operation amount of the brake operator, so that even a vehicle brake control device that does not include a pressure sensor can properly determine the release of the brake operator.

[0007] Furthermore, the control unit may determine that the brake operator has been released if the operation amount has been continuously decreasing for a first predetermined time during the release determination.

[0008] According to this configuration, since it is determined that the amount of operation has been continuously decreasing for the first predetermined time in the release determination, it is possible to improve the accuracy of the release determination.

[0009] Furthermore, the control unit may set a release flag when it determines that the brake operator has been released, and may reset the release flag when the operation amount becomes equal to or less than a second predetermined value that is smaller than the first predetermined value.

[0010] According to this configuration, the release flag is lowered when the manipulated variable becomes equal to or less than a second predetermined value that is smaller than the first predetermined value, so that, for example, pressure reduction control that is performed when the release flag is set can be terminated at an appropriate timing.

[0011] Furthermore, if the amount of operation increases while the release flag is set, the control unit may reset the release flag.

[0012] According to this configuration, if the operation amount increases while the release flag is set, the release flag is lowered, so that, for example, pressure reduction control performed while the release flag is set can be terminated by re-input of the brake operator.

[0013] Furthermore, the control unit may turn off the release flag if the amount of operation continues to increase for a second predetermined time while the release flag is set.

[0014] According to this configuration, a re-input of the brake operator is determined based on the fact that the operation amount has continued to increase for the second predetermined time, so that the accuracy of the determination of the re-input of the brake operator can be improved.

[0015] The vehicle brake control device may further include an angle sensor that detects the angle of the brake operator, and the control unit may acquire the angle detected by the angle sensor as the operation amount.

[0016] According to this configuration, by using the angle sensor, it is possible to provide an inexpensive vehicle brake control device. [Brief explanation of the drawings]

[0017] [Figure 1] 1 is a diagram showing the configuration of a motorcycle equipped with a vehicle brake control device according to an embodiment; [Figure 2] 10 is a flowchart showing the operation of a control unit. [Figure 3] 4 is a time chart showing a specific example of the operation of the control unit. [Figure 4] 10 is a flowchart illustrating an operation of a control unit according to a modified example. [Figure 5] 10A and 10B are diagrams illustrating a method for setting an instruction current value by a control unit according to a modified example. DETAILED DESCRIPTION OF THE INVENTION

[0018] Hereinafter, the embodiments will be described in detail with reference to the drawings as appropriate. As shown in FIG. 1, the motorcycle MC includes an engine ENG, a transmission TM, and a vehicle brake control device C.

[0019] The engine ENG is a drive source that imparts driving force to the rear wheel WR, and is connected to the rear wheel WR via the transmission TM. That is, in the motorcycle MC of this embodiment, the rear wheel WR is a drive wheel, and the front wheel WF is a driven wheel. The engine ENG is provided with a throttle sensor 54 that detects the opening of a throttle valve of the engine ENG. The opening of the throttle valve increases as the amount of operation of the accelerator AC increases. The transmission TM is a mechanism that changes the speed and transmits the driving force of the engine ENG to the rear wheel WR, and a speed detection sensor 52 is provided near the output shaft of the transmission TM.

[0020] The speed detection sensor 52 is a sensor (so-called speedometer sensor) that detects the wheel speed of the rear wheels WR, and detects the wheel speed corresponding to the speed displayed on a speedometer (not shown). The speed detection sensor 52 has a different detection method from the wheel speed sensor 51 that detects the wheel speed of the front wheels WF. The wheel speed sensor 51 is a sensor that generates a pulse wave in response to the rotation of the wheels.

[0021] The vehicle brake control device C includes a brake system BF for the front wheels WF, a brake system BR for the rear wheels WR, and a control unit 100.

[0022] The brake system BF is mainly composed of a front brake lever LF, a master cylinder MF, a hydraulic unit 10, a front brake 20F as an example of a wheel brake, a pipe 30 connecting the master cylinder MF to the input port 11a of the hydraulic unit 10, and a pipe 40 connecting the output port 11b of the hydraulic unit 10 to the front brake 20F.

[0023] The front brake lever LF is an operating lever for actuating the front brake 20F, and is located on the right side of the handlebar of the motorcycle MC so that it can be operated with the right hand of the rider. The front brake lever LF is connected to the front brake 20F via the master cylinder MF, piping 30, hydraulic unit 10, and piping 40. The master cylinder MF is a device that outputs hydraulic pressure according to the amount of operation of the front brake lever LF.

[0024] The front brake 20F is a brake that brakes the front wheels WF. The front brake 20F mainly includes a brake rotor 21, brake pads (not shown), and a wheel cylinder 23 that generates a braking force (braking force) by pressing the brake pads against the brake rotor 21 using hydraulic pressure output from a master cylinder MF.

[0025] The hydraulic unit 10 is a unit that applies hydraulic pressure to the front brake 20F to generate braking force of the front brake 20F. The hydraulic unit 10 is configured by arranging various electromagnetic valves and the like in a pump body 11, which is a base body having an oil passage (hydraulic pressure passage) through which brake fluid flows. Under normal circumstances, an oil passage is connected from the input port 11a to the output port 11b of the pump body 11, so that the hydraulic pressure output from the master cylinder MF is transmitted to the front brake 20F.

[0026] A pressure regulating valve 7 is provided on the hydraulic pressure path connecting the input port 11a and the output port 11b, and changes the hydraulic pressure applied to the front brake 20F in accordance with the value of the command current output from the control unit 100. The pressure regulating valve 7 is a normally open proportional solenoid valve that is capable of adjusting the difference in hydraulic pressure upstream and downstream thereof in accordance with the value of the command current. More specifically, the pressure regulating valve 7 is configured so that the greater the magnitude of the command current, the greater the difference in hydraulic pressure upstream and downstream of the pressure regulating valve 7. A check valve 7a is provided in parallel with the pressure regulating valve 7, and allows flow only toward the output port 11b.

[0027] Inlet valve 1, which is a normally open solenoid valve, is disposed on the hydraulic path between pressure regulating valve 7 and output port 11b. A check valve 1a that allows flow only to the pressure regulating valve 7 side is provided in parallel with inlet valve 1.

[0028] A return hydraulic line 19B is provided from the hydraulic line between the output port 11b and the inlet valve 1 to the hydraulic line between the pressure regulating valve 7 and the inlet valve 1 via an outlet valve 2 made of a normally closed solenoid valve.

[0029] Arranged on this return hydraulic line 19B, in this order from the outlet valve 2 side, are a reservoir 3 that temporarily absorbs excess brake fluid, a check valve 3a, a pump 4, and an orifice 4a. The check valve 3a is positioned so as to allow flow only toward the hydraulic line between the pressure regulating valve 7 and the inlet valve 1. The pump 4 is driven by a motor 6 and is provided to generate pressure toward the hydraulic line between the pressure regulating valve 7 and the inlet valve 1. The orifice 4a damps pressure pulsations of the brake fluid discharged from the pump 4 and pulsations generated by the operation of the pressure regulating valve 7.

[0030] An intake hydraulic pressure line 19C connects an intake hydraulic pressure line 19A connecting the input port 11a and the pressure regulating valve 7 to a portion of the return hydraulic pressure line 19B between the check valve 3a and the pump 4. A mechanical intake valve 8 is disposed in the intake hydraulic pressure line 19C.

[0031] Intake valve 8 switches intake hydraulic pressure line 19C between an open state and a closed state. Intake valve 8 is normally closed and is configured to open depending on the difference between the hydraulic pressure of the hydraulic fluid on the master cylinder MF side and the hydraulic pressure of the hydraulic fluid on the intake port side of pump 4, which becomes negative pressure when pump 4 is activated.

[0032] In the hydraulic unit 10 configured as described above, under normal conditions, the solenoid valves are not energized, and brake fluid pressure introduced from the input port 11a is output to the output port 11b through the pressure regulator valve 7 and the inlet valve 1, and is directly applied to the front brakes 20F. To reduce excessive brake fluid pressure in the front brakes 20F, such as during anti-lock brake control, the inlet valve 1 is closed and the outlet valve 2 is opened, allowing brake fluid to flow through the return fluid pressure path 19B to the reservoir 3, thereby draining the brake fluid from the front brakes 20F. To pressurize the front brakes 20F without the driver operating the front brake lever LF, for example, the motor 6 is driven to open the intake valve 8, and the pressure of the pump 4 actively supplies brake fluid to the front brakes 20F. Furthermore, the degree of pressurization of the front brakes 20F can be adjusted by adjusting the current flowing through the pressure regulator valve 7.

[0033] The brake system BR is mainly configured to have a rear brake lever LR as an example of a brake operator, an angle sensor 53, a rear brake 20R, and a wire W connecting the rear brake lever LR and the rear brake 20R.

[0034] The rear brake lever LR is an operating lever for actuating the rear brake 20R, and is located on the left side of the handlebar of the motorcycle MC so that it can be operated with the rider's left hand. The rear brake lever LR is connected to the rear brake 20R via a wire W. The angle sensor 53 is a sensor for detecting the operation angle of the rear brake lever LR.

[0035] The rear brake 20R is a brake that applies brakes to the rear wheel WR, and is a mechanical brake that is activated when the force generated when the rear brake lever LR is gripped is transmitted via a wire W. The rear brake 20R cannot be operated with the front brake lever LF. The rear brake 20R is, for example, a drum brake, and has a drum 25 and a brake shoe and return spring (not shown).

[0036] The drum 25 is rotatable integrally with the rear wheel WR. The brake shoe is rotatable between a contact position where it contacts the inner circumferential surface of the drum 25 and a spaced position where it is separated from the inner circumferential surface of the drum 25. A return spring biases the brake shoe from the contact position toward the spaced position. When the rider grips the rear brake lever LR, the wire W is pulled by the rear brake lever LR, causing the brake shoe to rotate from the spaced position toward the contact position against the biasing force of the return spring.

[0037] The control unit 100 is configured to include, for example, a CPU (Central Processing Unit), RAM (Random Access Memory), ROM (Read Only Memory), input / output circuits, etc. The control unit 100 controls the hydraulic unit 10 by performing various arithmetic processing based on inputs from the wheel speed sensors 51, the speed detection sensor 52, the angle sensor 53, and the throttle sensor 54, as well as programs and data stored in the ROM.

[0038] The control unit 100 is capable of executing braking force control that controls the braking force of the front brake 20F based on the amount of operation of the rear brake lever LR. The control unit 100 acquires the operation angle θ of the rear brake lever LR detected by the angle sensor 53 as the amount of operation. The control unit 100 starts braking force control when the operation angle θ becomes equal to or greater than a start threshold value θs. The control unit 100 ends braking force control when the operation angle θ becomes equal to or less than a second predetermined value θth2 during execution of braking force control.

[0039] During braking force control, the control unit 100 executes pressurization control, release determination, and pressure reduction control. In other words, the brake control method by the control unit 100 includes a pressurization step of executing pressurization control, a release determination step of executing release determination, and a pressure reduction step of executing pressure reduction control.

[0040] The pressurization control is a control that makes the hydraulic pressure of the front brake 20F higher than when the hydraulic unit 10 is not controlled by the control unit 100. During the pressurization control, the control unit 100 controls the braking force (hydraulic pressure) of the front brake 20F based on the operation of the rear brake lever LR.

[0041] Specifically, the control unit 100 executes pressurization control by driving the motor 6 and controlling the pressure regulating valve 7. The control unit 100 calculates the value of the command current value to be output to the pressure regulating valve 7 based on the operation angle θ and the vehicle body deceleration. Here, the vehicle body deceleration can be calculated based on the wheel speed acquired from the wheel speed sensor 51, for example. The control unit 100 increases the command current value as the operation angle θ increases, and increases the command current value as the magnitude of the vehicle body deceleration decreases.

[0042] In the pressurization control, the control unit 100 limits the increase in braking force (hydraulic pressure) of the front brake 20F so that the increase rate per unit time of the braking force (hydraulic pressure) is equal to or less than an upper limit value. Specifically, for example, the control unit 100 limits the increase in braking force of the front brake 20F by calculating a command current value using the following equation (1). A n =min(A n ,A n-1 +Au) (1) A n : Current indicated current value A n-1 :Previous indicated current value Au: Upper limit (fixed value) That is, the control unit 100 determines the current value A of the command current value. n and the previous value A of the indicated current value n-1 The smaller value is the current value A of the indicated current value. n It is determined as follows.

[0043] The release determination is a process for determining whether the rear brake lever LR has been released during pressure control. The control unit 100 starts the release determination when the operating angle θ of the rear brake lever LR becomes equal to or less than a first predetermined value θth1. The control unit 100 determines that the rear brake lever LR has been released if the operating angle θ has decreased from the first predetermined value θth1 during the release determination. In more detail, the control unit 100 determines that the rear brake lever LR has been released if the operating angle θ has been decreasing continuously for a first predetermined time T1 during the release determination.

[0044] To determine whether the operating angle θ has been decreasing continuously for the first predetermined time T1, for example, a method can be employed in which a control loop of the pressure control is performed multiple times, and if the current value of the operating angle θ is smaller than the previous value in all of the multiple control loops, it is determined that the operating angle θ has been decreasing continuously for the first predetermined time T1. Specifically, for example, a timer may be started to measure time when the operating angle θ becomes equal to or smaller than the first predetermined value θth1, and a determination may be made as to whether the current value of the operating angle θ is smaller than the previous value in all of the multiple control cycles executed until the timer reaches the first predetermined time T1. The timer may be reset when the measured time becomes equal to or greater than the first predetermined time T1.

[0045] Another method for determining whether the operating angle θ has been decreasing continuously for the first predetermined time T1 is to refer to the history of the operating angle θ for a period going back from the start of the release determination, and determine whether the operating angle θ has been decreasing continuously for the first predetermined time T1 based on the history of the operating angle θ. This method does not require the use of a timer.

[0046] When the control unit 100 determines that the rear brake lever LR has been released, it sets a release flag F indicating that the rear brake lever LR has been released, and executes pressure reduction control while the release flag F is set.

[0047] The pressure reduction control is a control for gradually reducing the braking force of the front brake 20F when it is determined in the release determination that the rear brake lever LR has been released. Here, "gradually reducing the braking force of the front brake 20F" means reducing the braking force of the front brake 20F at a gradient that is lower than the gradient at which the braking force of the front brake 20F is reduced at the fastest speed.

[0048] The control unit 100 executes pressure reduction control by controlling the pressure regulator valve 7 while the motor 6 is stopped. The control unit 100 determines that the rear brake lever LR has been released and sets the command current value A n If the command current value A is equal to or greater than the threshold value Ath, the first pressure reduction amount D1 is set. n " is simply "Indicated current value A when release is judged n "It is also called ".

[0049] The control unit 100 determines the release current value A n If the previous value A of the command current value is less than the threshold value Ath, the control unit 100 sets a second pressure reduction amount D2 that is smaller than the first pressure reduction amount D1. n-1 The value obtained by subtracting the set pressure reduction amount D (first pressure reduction amount D1 or second pressure reduction amount D2) from the current value A of the indicated current value. n Let's say.

[0050] During pressure reduction control, that is, when the release flag F is set, if the operating angle θ becomes equal to or less than a second predetermined value θth2 that is smaller than the first predetermined value θth1, the control unit 100 clears the release flag F and terminates the pressure reduction control (braking force control). Furthermore, if the operating angle θ increases during pressure reduction control, that is, when the release flag F is set, the control unit 100 clears the release flag F, terminates the pressure reduction control, and resumes the pressure increase control. In this embodiment, the control unit 100 clears the release flag F if the operating angle θ continues to increase for a second predetermined time T2 while the release flag F is set.

[0051] Note that, to determine whether the operating angle θ has continuously increased for the second predetermined time T2, for example, a method can be adopted in which a control loop of the pressure reduction control is performed multiple times, and if the current value of the operating angle θ is greater than the previous value in all of the multiple control loops, it is determined that the operating angle θ has continuously decreased for the second predetermined time T2. The second predetermined time T2 may be the same value as the first predetermined time T1, or may be a different value.

[0052] Next, a detailed description will be given of the operation of the control unit 100. The control unit 100 constantly and repeatedly executes the process shown in FIG.

[0053] 2, the control unit 100 first starts acquiring the operating angle θ of the rear brake lever LR from the angle sensor 53 (S1). After step S1, the control unit 100 determines whether the operating angle θ is equal to or greater than the start threshold value θs (S2). If it is determined in step S2 that θ<θs (No), the control unit 100 ends this process.

[0054] If it is determined in step S2 that θ≧θs (Yes), the control unit 100 starts the pressurization control (S3 to S6). In the pressurization control, the control unit 100 determines the command current value A based on the operation angle θ and the vehicle body deceleration. n After step S3, the control unit 100 calculates the command current value A calculated in step S3. n and the previous value A of the indicated current value n-1 The smaller value is the current value A of the indicated current value. n Let (S4).

[0055] In the pressurization control, the control unit 100 not only outputs a command current value to the pressure regulator valve 7 but also drives the motor 6, and the timing at which the motor 6 starts to drive may be set to any appropriate timing.

[0056] After step S4, the control unit 100 determines whether or not the operation angle θ has become equal to or less than a first predetermined value θth1 (S5). If it is determined in step S5 that θ≦θth1 (Yes), the control unit 100 performs a release determination (S6, S7).

[0057] In the release determination, the control unit 100 determines whether or not the operation angle θ has continuously decreased for a first predetermined time T1 (S6). If it is determined in step S6 that the operation angle θ has continuously decreased for the first predetermined time T1 (Yes), the control unit 100 determines that the rear brake lever LR has been loosened and sets a release flag F, that is, sets F = 1 (S7).

[0058] If it is determined No in step S5 or step S6, the control unit 100 returns to the process of step S3. After step S7, the control unit 100 executes decompression control (S8 to S15). When starting the decompression control, the control unit 100 stops the motor 6, but the timing of stopping the motor 6 may be set at an appropriate timing.

[0059] In the decompression control, the control unit 100 determines whether or not the commanded current value A n at the time of the release determination is equal to or greater than a threshold value Ath (S8). If it is determined in step S8 that A n ≧Ath (Yes), the control unit 100 sets the first decompression amount D1 as the decompression amount D (S9). If it is determined in step S8 that A n <Ath (No), the control unit 100 sets a second decompression amount D2 smaller than the first decompression amount D1 as the decompression amount D (S10).

[0060] After step S9 or step S10, the control unit 100 sets a value obtained by subtracting the decompression amount D from the previous value A n-1 of the commanded current value as the current value A n of the commanded current value (S11). After step S11, the control unit 100 determines whether or not the operation angle θ has continuously increased for a second predetermined time T2 (S12).

[0061] If it is determined in step S12 that the operating angle θ has not increased continuously for the second predetermined time T2 (No), the control unit 100 determines whether the operating angle θ has become equal to or less than a second predetermined value θth2 (S13). If it is determined in step S13 that θ≦θth2 is not satisfied (No), the control unit 100 returns to the processing of step S11.

[0062] If it is determined in step S13 that θ≦θth2 (Yes), the control unit 100 clears the release flag F, that is, sets F=0 (S14). After step S14, the control unit 100 n is set to 0 (S15), and this process ends.

[0063] If it is determined in step S12 that the operating angle θ has increased continuously for the second predetermined time T2 (Yes), the control unit 100 sets the release flag F to 0 (S16) and returns to the processing of step S3. In other words, if the operating angle θ has increased continuously for the second predetermined time T2 during pressure reduction control, the control unit 100 ends the pressure reduction control and resumes the pressure increase control.

[0064] Next, a specific example of the operation of the control unit 100 will be described in detail. For example, when a rider operates a rear brake lever LR while the motorcycle MC is running, as shown in FIG. 3, the control unit 100 controls the command current value A based mainly on the operation angle θ and the vehicle deceleration. n (time t0 to t1) When the driver eases up on the operation of the rear brake lever LR during the pressure control, and the operation angle θ becomes equal to or smaller than the first predetermined value θth1, the control unit 100 starts measuring time using a timer and starts a release determination (time t1).

[0065] If the operating angle θ continues to decrease for a first predetermined time T1 from the start of the release determination, the control unit 100 determines that the operation of the rear brake lever LR has been eased, sets a release flag F, and starts pressure reduction control (time t2). nis equal to or greater than the threshold Ath, the control unit 100 controls the instructed current value A at the first pressure reduction amount D1, as shown by the solid line. n This reduces the indicated current value A n However, since the hydraulic pressure gradually decreases at a first gradient G1 corresponding to the first pressure reduction amount D1, the hydraulic pressure of the front brake 20F can be gradually decreased at a first hydraulic pressure gradient corresponding to the first gradient G1.

[0066] Indicated current value A at time t2 n is less than the threshold value Ath, the control unit 100 sets the command current value A at a second pressure reduction amount D2 that is smaller than the first pressure reduction amount D1, as shown by the two-dot chain line. n This reduces the indicated current value A n However, since the hydraulic pressure gradually decreases at a second gradient G2 that is gentler than the first gradient G1, the hydraulic pressure of the front brake 20F can be gradually decreased at a gentle second hydraulic pressure gradient corresponding to the second gradient G2.

[0067] Thereafter, when the operating angle θ becomes equal to or less than the second predetermined value θth2 (time t3), the control unit 100 clears the release flag F, ends the pressure reduction control, and ends the braking force control. n is shown to be exactly 0 at the end of braking force control, but the command current value A n Depending on the value of , the command current value A n When the braking force control ends, the command current value A n becomes a value greater than 0. When braking force control ends, the command current value A n If the value is greater than 0, the command current value A n is set to 0.

[0068] As described above, according to this embodiment, the following effects can be obtained. When the rear brake lever LR is released, the braking force of the front brake 20F is gradually reduced, so that the sense of discomfort felt by the rider when the rear brake lever LR is released can be reduced.

[0069] Indicated current value A when rear brake lever LR is released n Since pressure reduction control is performed with a pressure reduction amount D according to the value of (a), the operating feeling can be improved.

[0070] Even if the rear brake lever LR is re-input during pressure reduction control and pressure increase control is resumed, the processing of step S4 limits a sudden increase in the braking force of the front brake 20F during pressure reduction control, thereby stabilizing the vehicle behavior.

[0071] Since the release determination is made based on the amount of operation of the rear brake lever LR, even a vehicle brake control device C that does not include a pressure sensor can properly determine the release of the rear brake lever LR.

[0072] In the release determination, it is determined that the operation angle θ has been continuously decreasing for the first predetermined time T1, so that the accuracy of the release determination can be improved.

[0073] When the operating angle θ becomes equal to or less than a second predetermined value θth2 that is smaller than the first predetermined value θth1, the release flag F is lowered, so that the pressure reduction control that is performed when the release flag F is set can be terminated at an appropriate timing.

[0074] When the release flag F is set, if the operating angle θ increases, the release flag F is lowered, so that the pressure reduction control performed when the release flag F is set can be ended by the re-input of the rear brake lever LR.

[0075] Since the re-input of the rear brake lever LR is determined based on the fact that the operating angle θ has continued to increase for the second predetermined time T2, the accuracy of the determination of the re-input of the rear brake lever LR can be improved.

[0076] Since the release determination is performed using the angle sensor 53, an inexpensive vehicle brake control device C can be provided.

[0077] The present invention is not limited to the above-described embodiment, but can be used in various forms as exemplified below. In the following description, members having substantially the same structure as those in the above-described embodiment are given the same reference numerals, and their description will be omitted.

[0078] The method of gradually decreasing the command current value in the pressure reduction control is not limited to the method in the above embodiment. For example, as shown in Fig. 5, the control unit 100 determines that the rear brake lever LR has been released based on the command current value Ar and the operation angle θr, and determines when the operation angle θ of the rear brake lever LR becomes a second predetermined value θth2. n The command current value A is adjusted according to the decrease in the operating angle θ so that n may be gradually decreased.

[0079] Specifically, the indicated current value A during pressure reduction control n can be calculated using the following formula (2). A n =a·(θ-θth2) ···(2) a=Ar / (θr-θth2) Ar: Indicated current value at release judgment θr: Control angle at release judgment

[0080] In this equation (2), the indicated current value A n By calculating the indicated current value A n The current gradually decreases with the aforementioned gradient a as the operating angle θ decreases, and when the operating angle θ reaches the second predetermined value θth2, the command current value A n can be set to 0. In this embodiment, the control unit 100 executes the process shown in FIG.

[0081] The process shown in FIG. 4 is configured by adding a new step S31 instead of steps S8 to S11 in the process shown in FIG. 2. In step S31, the command current value A nAfter step S7, the control unit 100 executes the process of step S31, and then proceeds to the process of step S12. If the determination in step S13 is No, the control unit 100 returns to the process of step S31.

[0082] According to this embodiment, when the operating angle θ reaches the second predetermined value θth2, that is, when the braking force control is completed, the command current value A n Since it is possible to further prevent the value from suddenly becoming 0, it is possible to further reduce the sense of discomfort felt by the driver.

[0083] In the above embodiment, the upper limit value Au for limiting the increase in the braking force of the front brake 20F is a fixed value, but the upper limit value Au may be variable. For example, the upper limit value Au1 during the initial pressure increase control in the braking force control may be different from the upper limit value Au2 during the pressure increase control when the pressure increase control is resumed from the pressure decrease control. For example, Au2<Au1としてもよいし、Au2> It may also be Au1.

[0084] In the above embodiment, the release determination is made when the operating angle θ continuously decreases for the first predetermined time T1. However, for example, the release determination may also be made when the operating angle θ intermittently decreases for the first predetermined time T1. As a method for determining whether the operating angle θ has intermittently decreased, for example, the operating angle θ may be determined to have intermittently decreased when, among the multiple control loops, the number of control loops in which the current value of the operating angle θ is smaller than the previous value is greater than the number of control loops in which the current value of the operating angle θ is greater than the previous value. The determination of whether the operating angle θ has continuously increased may also be changed to a method for determining whether the operating angle θ has intermittently increased. The determination of whether the operating angle θ has intermittently increased may be made using the same method as the method for determining whether the operating angle θ has intermittently decreased, described above.

[0085] In the above embodiment, the operating angle θ of the rear brake lever LR is exemplified as the operating amount, but the operating amount may be, for example, a stroke amount detected by a stroke sensor that detects the stroke of an operating element such as a brake lever or a foot brake, or a distance detected by a distance sensor such as an infrared sensor that detects the distance between the operating element and a support member that movably supports the operating element.

[0086] The wheel brakes are not limited to hydraulic brakes and may be, for example, electromagnetic brakes. The rear brakes are not limited to mechanical brakes and may be, for example, electromagnetic or hydraulic brakes. If the rear brakes are electromagnetic or hydraulic brakes, the braking force of the rear brakes may be controlled based on the amount of operation of the front wheel brake operator.

[0087] The vehicle provided with the wheel brake is not limited to a motorcycle MC, but may be any type of vehicle. For example, the vehicle may be a bar handle vehicle operated with a bar handle. The bar handle vehicle may be, for example, a three-wheeled vehicle or a four-wheeled vehicle.

[0088] The brake operator is not limited to a lever, but may be, for example, a foot brake pedal.

[0089] The intake valve may be a normally closed solenoid valve.

[0090] The elements described in the above-described embodiment and modified examples may be implemented in any combination.

Claims

1. A vehicle brake control device including a control unit that controls the braking force of a wheel brake based on an operation amount of a brake operator, The control unit When the operation amount of the brake operator becomes equal to or less than a first predetermined value, a release determination is initiated to determine whether the brake operator has been released; A vehicle brake control device characterized in that, during the release determination, it is determined that the brake operator has been released if the operation amount continues to decrease from the first predetermined value for a first predetermined time.

2. A vehicle brake control device having a control unit that controls the braking force of a wheel brake based on the amount of operation of a brake operator, The control unit When the operation amount of the brake operator becomes equal to or less than a first predetermined value, a release determination is initiated to determine whether the brake operator has been released; During the release determination, if the operation amount is decreased from the first predetermined value, it is determined that the brake operator has been released; When it is determined that the brake operator has been released, a release flag is set; The vehicle brake control device is characterized in that the release flag is turned down when the operation amount becomes equal to or less than a second predetermined value that is smaller than the first predetermined value.

3. A vehicle brake control device including a control unit that controls the braking force of a wheel brake operated by a front wheel brake operator provided in a front wheel brake system based on the amount of operation of a brake operator provided in a rear wheel brake system, The control unit When the operation amount of the brake operator becomes equal to or less than a first predetermined value, a release determination is initiated to determine whether the brake operator has been released; The vehicle brake control device is characterized in that, during the release determination, it is determined that the brake operator has been released if the operation amount has decreased from the first predetermined value.

4. The control unit When it is determined that the brake operator has been released, a release flag is set; 2. The vehicle brake control device according to claim 1, wherein the release flag is cleared when the operation amount becomes equal to or less than a second predetermined value that is smaller than the first predetermined value.

5. The control unit 5. The vehicle brake control device according to claim 4, wherein the release flag is reset when the operation amount increases while the release flag is set.

6. The control unit 6. The vehicle brake control device according to claim 5, wherein the release flag is reset when the operation amount continues to increase for a second predetermined time while the release flag is set.

7. An angle sensor is further provided to detect the angle of the brake operator.

7. The vehicle brake control device according to claim 1, wherein the control unit acquires an angle detected by the angle sensor as the operation amount.

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