Vehicle brake control device and brake control method

Abstract

A vehicle brake control device C comprises: a first brake operation element that is connected to a first brake; a second brake that cannot be operated using the first brake operation element; a second brake operation element that is connected to the second brake; and a control unit that performs braking force control to control the braking force of the first brake on the basis of an operation on the second brake operation element. During the braking force control, the control unit performs pressurization control (S3 to S6) to control the braking force of the first brake on the basis of the operation on the second brake operation element, release determination (S6, S7) to determine whether or not the second brake operation element has been eased off during the pressurization control, and, when it has been determined in the release determination that the second brake operation element has been eased off, decompression control (S8 to S15) to decrease the braking force of the first brake.

Description

[Technical Field]

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

[0002] Conventionally, a known vehicle brake control system is provided with a hydraulic brake system for the front wheels and a mechanical brake for the rear wheels, and controls the hydraulic pressure of the front brake system in response to the operation of a rear brake lever connected to the rear wheels (see International Publication No. 2020 / 026678). [Overview of the project]

[0003] However, if the hydraulic pressure of the brake system is rapidly reduced when the rear brake lever is released while the hydraulic pressure of the brake system is being controlled in response to the operation of the rear brake lever, it may cause discomfort to the driver.

[0004] Therefore, the present invention aims to reduce the discomfort felt by the driver when the second brake lever is released, in a configuration comprising a first brake that can be operated by a first brake lever and a second brake lever, and a second brake that cannot be operated by the first brake lever.

[0005] To solve the aforementioned problems, the vehicle brake control device according to the present invention comprises a first brake operator connected to a first brake, a second brake that cannot be operated by the first brake operator, a second brake operator connected to the second brake, and a control unit capable of performing brake force control that controls the braking force of the first brake based on the operation of the second brake operator. During braking force control, the control unit performs pressurization control, which controls the braking force of the first brake based on the operation of the second brake lever; release determination, which determines whether or not the second brake lever has been released during pressurization control; and depressurization control, which gradually reduces the braking force of the first brake if the release determination determines that the second brake lever has been released.

[0006] Furthermore, the brake control method according to the present invention is a brake control method using a vehicle brake control device comprising: a first brake operator connected to a first brake; a second brake that cannot be operated by the first brake operator; a second brake operator connected to the second brake; and a control unit capable of performing brake force control to control the braking force of the first brake based on the operation of the second brake operator. In the brake control method, the control unit performs a pressurization step to control the braking force of the first brake based on the operation of the second brake operator; a release determination step to determine whether or not the second brake operator has been released during the pressurization step; and a depressurization step to gradually reduce the braking force of the first brake if it is determined in the release determination step that the second brake operator has been released.

[0007] With these configurations, when the second brake lever is released, the braking force of the first brake is gradually reduced, thereby reducing the discomfort felt by the driver when the second brake lever is released.

[0008] Furthermore, the vehicle brake control device is a hydraulic unit that generates braking force for the first brake by applying hydraulic pressure to the first brake, and further comprises a hydraulic unit equipped with a pressure regulating valve that changes the hydraulic pressure applied to the first brake according to the value of the indicated current value, and the control unit may perform pressure reduction control by controlling the pressure regulating valve.

[0009] Furthermore, the control unit may perform pressurization control by controlling the pressure regulating valve, and if the instructed current value to the pressure regulating valve when it is determined that the second brake operator has been released is greater than or equal to a threshold, it may set a first pressure reduction amount, and during pressure reduction control, the value obtained by subtracting the first pressure reduction amount from the previous value of the instructed current value may be used as the current value of the instructed current value.

[0010] According to this configuration, since the pressure reduction control is executed with the pressure reduction amount corresponding to the value of the command current value when the second brake operator is released, the operation feeling can be improved.

[0011] Further, when the command current value to the pressure regulating valve when it is determined that the second brake operator is released is less than the threshold value, the control unit sets a second pressure reduction amount smaller than the first pressure reduction amount, and during the pressure reduction control, the value obtained by subtracting the second pressure reduction amount from the previous value of the command current value may be used as the current value of the command current value.

[0012] According to this configuration, since the pressure reduction control is executed with the pressure reduction amount corresponding to the value of the command current value when the second brake operator is released, the discomfort given to the driver can be reduced.

[0013] Further, the control unit executes the pressure increase control by controlling the pressure regulating valve, and is configured to end the braking force control when the operation amount of the second brake operator becomes less than or equal to a predetermined value during the execution of the braking force control, and based on the command current value and the operation amount when it is determined that the second brake operator is released, the command current value may be gradually decreased in response to the decrease in the operation amount so that the command current value becomes 0 when the operation amount of the second brake operator reaches the predetermined value.

[0014] According to this configuration, it is possible to further suppress the command current value from suddenly becoming 0 at the end of the braking force control, so that the discomfort given to the driver can be further reduced.

[0015] Further, during the pressure reduction control, when the operation amount of the second brake operator increases, the control unit may resume the pressure increase control and limit the increase in the braking force so that the increase amount of the braking force per unit time is less than or equal to the upper limit value.

[0016] According to this configuration, since the sudden increase in the braking force of the first brake when the second brake operator is re-input is suppressed, the vehicle body behavior can be stabilized.

Brief Description of the Drawings

[0017] [Figure 1] This figure shows the configuration of a motorcycle equipped with a vehicle brake control device according to this embodiment. [Figure 2] This is a flowchart showing the operation of the control unit. [Figure 3] This is a time chart illustrating a specific example of the operation of the control unit. [Figure 4] This flowchart shows the operation of the control unit in relation to the modified example. [Figure 5] This figure shows the method for setting the indicative current value by the control unit in a modified example. [Modes for carrying out the invention]

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

[0019] The engine ENG is a drive source that provides driving force to the rear wheel WR and is connected to the rear wheel WR via the transmission TM. In other words, in this embodiment of the motorcycle MC, the rear wheel WR is the drive wheel and the front wheel WF is the driven wheel. The engine ENG is equipped with a throttle sensor 54 that detects the opening degree of the engine ENG's throttle valve. The opening degree of the throttle valve is greater the greater the amount of accelerator AC is operated. The transmission TM is a mechanism that transmits the driving force of the engine ENG to the rear wheel WR after shifting the gear ratio, and a speed detection sensor 52 is provided near its output shaft.

[0020] The speed detection sensor 52 is a sensor (so-called speedometer sensor) that detects the wheel speed of the rear wheel 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 than the wheel speed sensor 51 that detects the wheel speed of the front wheel WF. The wheel speed sensor 51 is a sensor that generates pulse waves in conjunction with the rotation of the wheel.

[0021] The vehicle brake control device C comprises 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 mainly consists of a front brake lever LF as an example of a first brake operator, a master cylinder MF, a hydraulic unit 10, a front brake 20F as an example of a first brake, a pipe 30 connecting the master cylinder MF and the input port 11a of the hydraulic unit 10, and a pipe 40 connecting the output port 11b of the hydraulic unit 10 and the front brake 20F.

[0023] The front brake lever LF is the operating lever for activating the front brake 20F. It is located on the right side of the handlebars of the motorcycle MC and can be operated with the driver's right hand. 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 corresponding to the amount of movement of the front brake lever LF.

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

[0025] The hydraulic unit 10 is a unit that generates braking force for the front brake 20F by applying hydraulic pressure to the front brake 20F. The hydraulic unit 10 is composed of a pump body 11, which is a base body having an oil passage (hydraulic passage) through which brake fluid flows, and various electromagnetic valves and the like are arranged on it. Normally, the input port 11a to the output port 11b of the pump body 11 are connected by an oil passage, 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 path connecting the input port 11a and the output port 11b. This valve changes the hydraulic pressure applied to the front brake 20F according to the value of the indicative current output from the control unit 100. The pressure regulating valve 7 is a normally open proportional solenoid valve and can adjust the difference in hydraulic pressure between its upstream and downstream sides according to the value of the indicative current. Specifically, the pressure regulating valve 7 is configured such that the larger the indicative current value, the greater the difference in hydraulic pressure between the upstream and downstream sides of the pressure regulating valve 7. A check valve 7a is provided in parallel with the pressure regulating valve 7, which allows flow only to the output port 11b side.

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

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

[0029] On this recirculating hydraulic pressure passage 19B, a reservoir 3 for temporarily absorbing excess brake fluid, a check valve 3a, a pump 4, and an orifice 4a are arranged in order from the outlet valve 2 side. The check valve 3a is positioned to allow flow only toward the hydraulic pressure passage 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 pressure passage between the pressure regulating valve 7 and the inlet valve 1. The orifice 4a attenuates the pressure pulsation of the brake fluid discharged from the pump 4 and the pulsation generated by the operation of the pressure regulating valve 7.

[0030] The inlet hydraulic pressure passage 19A, which connects the input port 11a and the pressure regulating valve 7, and the section between the check valve 3a and the pump 4 in the return hydraulic pressure passage 19B are connected by the suction hydraulic pressure passage 19C. A mechanical suction valve 8 is installed in the suction hydraulic pressure passage 19C.

[0031] The suction valve 8 switches between opening and closing the suction fluid pressure passage 19C. The suction valve 8 is normally closed and is configured to open based on the difference between the hydraulic pressure of the working fluid on the master cylinder MF side and the hydraulic pressure of the working fluid on the suction port side of the pump 4, which becomes negative pressure when the pump 4 is operating.

[0032] In the hydraulic unit 10 configured as described above, under normal circumstances, no power is supplied to each solenoid valve. The brake fluid pressure introduced from the input port 11a passes through the pressure regulating valve 7 and the inlet valve 1 to the output port 11b, and is directly applied to the front brake 20F. When it is necessary to reduce the excessive brake fluid pressure of the front brake 20F, such as when performing anti-lock brake control, the inlet valve 1 is closed and the outlet valve 2 is opened, allowing the brake fluid to flow to the reservoir 3 through the return fluid pressure passage 19B, thereby draining the brake fluid from the front brake 20F. Furthermore, if it is necessary to pressurize the front brake 20F when the driver does not operate the front brake lever LF, for example, driving the motor 6 opens the suction valve 8, and the pressure from the pump 4 actively supplies brake fluid to the front brake 20F. In addition, if it is necessary to adjust the degree of pressurization of the front brake 20F, this can be done by adjusting the current flowing to the pressure regulating valve 7.

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

[0034] The rear brake lever LR is the operating lever for activating the rear brake 20R. It is located on the left side of the handlebars of the motorcycle MC and can be operated with the rider's left hand. The rear brake lever LR is connected to the rear brake 20R via wire W. The angle sensor 53 is a sensor for detecting the operating angle of the rear brake lever LR.

[0035] The rear brake 20R is a brake that stops the rear wheel WR, and is a mechanical brake that operates when the force applied when the rear brake lever LR is squeezed is transmitted via 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, brake shoes (not shown), and a return spring.

[0036] The drum 25 is rotatable in conjunction with the rear wheel WR. The brake shoe is rotatable between a contact position where it contacts the inner surface of the drum 25 and a separated position where it is away from the inner surface of the drum 25. The return spring biases the brake shoe from the contact position to the separated position. When the driver squeezes the rear brake lever LR, the wire W is pulled by the rear brake lever LR, causing the brake shoe to rotate from the separated position to 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), and input / output circuits. The control unit 100 controls the hydraulic unit 10 by performing various calculations based on inputs from the wheel speed sensor 51, speed detection sensor 52, angle sensor 53, and throttle sensor 54, as well as programs and data stored in the ROM.

[0038] The control unit 100 is capable of performing braking force control, which 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 operation amount. The control unit 100 starts braking force control when the operation angle θ becomes greater than or equal to a starting threshold θs. The control unit 100 terminates braking force control during the execution of braking force control when the operation angle θ becomes less than or equal to a second predetermined value θth2, which is an example of a predetermined value.

[0039] The control unit 100 performs pressurization control, release determination, and depressurization control during braking force control. In other words, the brake control method by the control unit 100 includes a pressurization step for performing pressurization control, a release determination step for performing release determination, and a depressurization step for performing depressurization control.

[0040] Pressurization control is a control mechanism that increases the hydraulic pressure of the front brake 20F to a higher level than when the hydraulic unit 10 is not being controlled by the control unit 100. During 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] More specifically, the control unit 100 performs pressurization control by driving the motor 6 and controlling the pressure regulating valve 7. The control unit 100 calculates the value of the instruction current output to the pressure regulating valve 7 based on the operating angle θ and the vehicle deceleration. Here, the vehicle deceleration can be calculated, for example, based on the wheel speed obtained from the wheel speed sensor 51. The control unit 100 increases the value of the instruction current as the operating angle θ increases, and increases the value of the instruction current as the vehicle deceleration decreases.

[0042] In pressurized control, the control unit 100 limits the increase in braking force (hydraulic pressure) of the front brake 20F so that the increase per unit time of the braking force (hydraulic pressure) is less than or equal to an upper limit. Specifically, for example, the control unit 100 limits the increase in braking force of the front brake 20F by calculating the indicated current value using the following equation (1). A n =min(A n ,A n-1 +Au) ···(1) A n : Current value of the indicated current A n-1 : Previous value of the indicated current Au: Upper limit (fixed value) In other words, the control unit 100 sets the current value A of the indicated current value. n And the previous value A of the indicated current value n-1 The value obtained by adding the upper limit value Au to the current value A is compared with the smaller value, and the current value A is used for the indicated current value. nThis will be decided.

[0043] The release determination is a process that determines whether the rear brake levers LR have been released during pressurization control. The control unit 100 starts the release determination when the operating angle θ of the rear brake levers LR becomes less than or equal to a first predetermined value θth1. During the release determination, the control unit 100 determines that the rear brake levers LR have been released if the operating angle θ decreases from the first predetermined value θth1. More specifically, the control unit 100 determines that the rear brake levers LR have been released if the operating angle θ continues to decrease for a first predetermined time T1 during the release determination.

[0044] To determine whether the operating angle θ is continuously decreasing for a first predetermined time T1, for example, one can employ a method in which the pressurization control loop is performed multiple times, and in all of the multiple control loops, if the current value of the operating angle θ is smaller than the previous value, it is determined that the operating angle θ is continuously decreasing for a first predetermined time T1. Specifically, for example, time measurement by a timer is started when the operating angle θ becomes less than or equal to a first predetermined value θth1, and in all of the multiple control cycles executed until the timer reaches the first predetermined time T1, it is determined whether the current value of the operating angle θ is smaller than the previous value. The timer should be reset when the measurement time reaches the first predetermined time T1 or longer.

[0045] Another determination method involves, for example, referring to the history of multiple operating angles θ over a period of a first predetermined time T1 prior to the start of the release determination, and determining, based on the history of operating angles θ, that the operating angle θ has been continuously decreasing for the first predetermined time T1. This method does not require the use of a timer.

[0046] If the control unit 100 determines that the rear brake levers LR have been released, it sets a release flag F to indicate that the rear brake levers LR have been released, and performs pressure reduction control while the release flag F is set.

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

[0048] The control unit 100 executes the pressure reduction control by controlling the pressure regulating valve 7 in a state where the motor 6 is stopped. The control unit 100 determines the indicated current value A to the pressure regulating valve 7 when it is determined that the rear brake lever LR has been loosened. n When it is above the threshold value Ath, the first pressure reduction amount D1 is set. In the following description, "the indicated current value A when it is determined that the rear brake lever LR has been loosened" n is simply referred to as "the indicated current value A at the time of release determination" n as well.

[0049] When the indicated current value A at the time of release determination 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. During the pressure reduction control, the control unit 100 subtracts the set pressure reduction amount D (the first pressure reduction amount D1 or the second pressure reduction amount D2) from the previous value A of the indicated current value to obtain the current value A of the indicated current value. n When the indicated current value A at the time of release determination 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. During the pressure reduction control, the control unit 100 subtracts the set pressure reduction amount D (the first pressure reduction amount D1 or the second pressure reduction amount D2) from the previous value A of the indicated current value to obtain the current value A of the indicated current value. n-1 from the previous value A of the indicated current value to obtain the current value A of the indicated current value. n as the current value A of the indicated current value.

[0050] During the pressure reduction control, that is, when the release flag F is set, when the operation 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 lowers the release flag F and ends the pressure reduction control (braking force control). Also, during the pressure reduction control, that is, when the release flag F is set, if the operation angle θ increases, the control unit 100 lowers the release flag F, ends the pressure reduction control, and resumes the pressure increase control. In the present embodiment, when the operation angle θ continuously increases for a second predetermined time T2 while the release flag F is set, the control unit 100 lowers the release flag F.

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

[0052] Next, the operation of the control unit 100 will be described in detail. The control unit 100 constantly repeats the process shown in Figure 2.

[0053] In the process shown in Figure 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 greater than or equal to the starting threshold θs (S2). If it is determined in step S2 that θ < θs (No), the control unit 100 terminates this process.

[0054] If it is determined in step S2 that θ ≥ θs (Yes), the control unit 100 starts pressurization control (S3~S6). In pressurization control, the control unit 100 sets an instructed current value A based on the operating angle θ and the vehicle deceleration. n The control unit 100 calculates the indicated current value A calculated in step S3. n And the previous value A of the indicated current value n-1 The current value A is determined by comparing this value with the upper limit value Au, and the smaller value is used as the current value A for the indicated current. n (S4)

[0055] In pressurization control, the control unit 100 outputs an instruction current value to the pressure regulating valve 7 and also drives the motor 6. The timing for starting the motor 6 can be set to an appropriate timing.

[0056] After step S4, the control unit 100 determines whether the operation angle θ has become equal to or less than the 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 the operation angle θ has continuously decreased for the 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 reliable brake lever LR has been loosened and sets the 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 - 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 the instructed current value A n at the time of release determination is equal to or greater than the 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 the second decompression amount D2, which is 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 the value obtained by subtracting the decompression amount D from the previous value A n-1 of the instructed current value as the current value A n of the instructed current value (S11). After step S11, the control unit 100 determines whether the operation angle θ has continuously increased for the second predetermined time T2 (S12).

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

[0062] If it is determined in step S13 that θ ≤ θth2 (Yes), the control unit 100 lowers the release flag F, that is, sets F = 0 (S14). After step S14, the control unit 100 sets the indicated current value A n Set this value to 0 (S15) and terminate this process.

[0063] If it is determined in step S12 that the operating angle θ has continued to increase for a second predetermined time T2 (Yes), the control unit 100 sets the release flag F to 0 (S16) and returns to the process in step S3. In other words, if the operating angle θ has continued to increase for a second predetermined time T2 during depressurization control, the control unit 100 terminates the depressurization control and restarts the pressurization control.

[0064] Next, a specific example of the operation of the control unit 100 will be described in detail. For example, when the driver operates the rear brake lever LR while the motorcycle MC is in motion, the control unit 100, as shown in Figure 3, outputs an instructed current value A based mainly on the operating angle θ and the vehicle deceleration. n By setting this, pressurization control is performed (time t0~t1). During pressurization control, when the driver releases the operation of the rear brake lever LR and the operation angle θ becomes less than or equal to a first predetermined value θth1, the control unit 100 starts measuring time with 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 released, sets the release flag F, and starts pressure reduction control (time t2). The indicated current value A at time t2. nIf the threshold Ath is greater than or equal to the threshold Ath, the control unit 100 sets the first reduction amount D1 to the indicated current value A, as shown by the solid line. n This will reduce the indicated current value A. n However, since it 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 reduced at a first hydraulic pressure gradient corresponding to the first gradient G1.

[0066] Indicated current value A at time t2 n If the value is less than the threshold Ath, the control unit 100 will set the indicated current value A to a second reduction amount D2 which is smaller than the first reduction amount D1, as shown by the dashed line. n This will reduce the indicated current value A. n However, since the pressure gradually decreases at a gentler second gradient G2 than at the first gradient G1, the hydraulic pressure of the front brake 20F can be gradually reduced at a gentle second hydraulic pressure gradient corresponding to the second gradient G2.

[0067] Subsequently, when the operating angle θ becomes less than or equal to the second predetermined value θth2 (time t3), the control unit 100 lowers the release flag F, terminates the pressure reduction control, and terminates the braking force control. Here, for convenience, in the figure, the instructed current value A to be reduced by the first gradient G1 or the second gradient G2 is shown. n However, although the diagram shows that it becomes exactly 0 at the end of braking force control, the indicated current value A at the time of release determination n Depending on the value, the indicated current value A will be set before the end of braking force control. n When it becomes 0, or when braking force control ends, the indicated current value A n The value may become greater than 0. The indicated current value A is reached at the end of braking force control. n If the value is greater than 0, the indicated current value A is determined by step S15 described above. n It is set to 0.

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

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

[0070] Even if the rear brake levers LR are re-input during depressurization control and pressurization control is restarted, the process in step S4 limits the rapid increase in braking force of the front brake 20F during pressurization control, thereby stabilizing the vehicle's behavior.

[0071] Since the release decision is made based on the amount of movement of the rear brake levers LR, even a vehicle brake control device C that does not have a pressure sensor can reliably determine the release of the rear brake levers LR.

[0072] In the release determination, it is determined that the operating angle θ has been decreasing for a first predetermined time T1, thus improving the accuracy of the release determination.

[0073] The release flag F is lowered when the operating angle θ becomes less than or equal to the second predetermined value θth2, which is smaller than the first predetermined value θth1. This allows the depressurization control performed when the release flag F is set to be terminated at an appropriate time.

[0074] When the release flag F is set and the operating angle θ increases, the release flag F is lowered. Therefore, the decompression control that is performed when the release flag F is set can be terminated by re-inputting 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 a second predetermined time T2, the accuracy of the determination of 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 embodiments described above and can be used in various forms as illustrated below. In the following description, components having substantially the same structure as those in the embodiments described above are denoted by the same reference numerals, and their descriptions are omitted.

[0078] The method for gradually reducing the indicative current value in pressure reduction control is not limited to the method described in the above embodiment. For example, as shown in Figure 5, the control unit 100 determines that the rear brake lever LR has been released and, based on the indicative current value Ar and the operating angle θr, when the operating angle θ of the rear brake lever LR becomes a second predetermined value θth2, the indicative current value A n The indicated current value A is adjusted according to the decrease in the operating angle θ so that it becomes 0. n The amount may be gradually reduced.

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

[0080] The indicated current value A is given by equation (2) in this way. n By calculating the indicated current value A, n However, with the aforementioned slope a, it gradually decreases as the operating angle θ decreases, and when the operating angle θ reaches the second predetermined value θth2, the indicated current value A n This can be set to 0. In this configuration, the control unit 100 should execute the process shown in Figure 4.

[0081] The process shown in Figure 4 has a configuration in which a new step S31 is added in place of steps S8 to S11 in the process shown in Figure 2. In step S31, the indicated current value A is determined by the aforementioned equation (2). nThe control unit 100 performs the processing in step S31 after step S7, and then proceeds to the processing in step S12. If it determines No in step S13, the control unit 100 returns to the processing in step S31.

[0082] In this configuration, when the operating angle θ reaches a second predetermined value θth2, that is, when braking force control ends, the instructed current value A is set. n This makes it possible to further suppress the sudden drop to zero, thus reducing the discomfort experienced by the driver.

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

[0084] In the above embodiment, the release determination was made when the operating angle θ continuously decreased for a first predetermined time T1. However, for example, the release may also be determined when the operating angle θ decreases intermittently for a first predetermined time T1. For example, a method for determining whether the operating angle θ decreased intermittently could be to determine if the operating angle θ decreased intermittently when 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 larger than the previous value. The determination of whether the operating angle θ is continuously increasing may also be changed to a method for determining whether the operating angle θ increased intermittently. The determination of whether the operating angle θ increased intermittently can be the same as the method for determining whether the operating angle θ decreased intermittently as described above.

[0085] In the above embodiment, the operating angle θ of the rear brake lever LR was exemplified as the operating amount, but the operating amount may be, for example, the stroke amount detected by a stroke sensor that detects the stroke of an operating element such as a brake lever or foot brake, or the 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 first brake is not limited to a hydraulic brake; for example, it may be an electromagnetic brake. The second brake is not limited to a mechanical brake; for example, it may be an electromagnetic brake or a hydraulic brake. Furthermore, the first brake may be used for the rear wheels and the second brake for the front wheels.

[0087] The vehicle equipped with the first and second brakes is not limited to motorcycles (MC), but can be any type of vehicle. For example, the vehicle may be a handlebar-operated vehicle. A handlebar-operated vehicle may be, for example, a three-wheeled or four-wheeled vehicle.

[0088] The brake control is not limited to a lever; it may also be a foot brake pedal, for example.

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

[0090] The elements described in the above embodiments and modifications may be implemented in any combination.

Claims

1. A first brake control element connected to the first brake, A second brake that cannot be operated by the first brake control, A second brake lever connected to the second brake, A vehicle brake control device comprising: a control unit capable of performing brake force control that controls the braking force of the first brake based on the operation of the second brake operator, The control unit, During the aforementioned braking force control, Pressurization control controls the braking force of the first brake based on the operation of the second brake operator, A release determination is made to determine whether the second brake lever was released during the pressurization control, A vehicle brake control device characterized in that, when it is determined in the release determination that the second brake operator has been released, it performs a depressurization control that gradually reduces only the braking force of the first brake without controlling the second brake.

2. A hydraulic unit that generates braking force of the first brake by applying hydraulic pressure to the first brake, further comprising a hydraulic unit equipped with a pressure regulating valve that changes the hydraulic pressure applied to the first brake according to the value of the indicated current value, The vehicle brake control device according to claim 1, characterized in that the control unit performs the pressure reduction control by controlling the pressure regulating valve.

3. A first brake operator connected to the first brake, A second brake that cannot be operated by the first brake control, A second brake lever connected to the second brake, A control unit capable of performing braking force control, which controls the braking force of the first brake based on the operation of the second brake operator, A vehicle brake control device comprising: a hydraulic unit that generates braking force of the first brake by applying hydraulic pressure to the first brake, the hydraulic unit having a pressure regulating valve that changes the hydraulic pressure applied to the first brake according to the value of an indicated current value, The control unit, During the aforementioned braking force control, Pressurization control controls the braking force of the first brake by controlling the pressure regulating valve based on the operation of the second brake operator, A release determination is made to determine whether the second brake lever was released during the pressurization control, If the release determination determines that the second brake operator has been released, the pressure regulating valve is controlled to gradually reduce the braking force of the first brake, and the following is performed: When it is determined that the second brake lever has been released, if the current value indicated to the pressure regulating valve is equal to or greater than the threshold value, the first pressure reduction amount is set. A vehicle brake control device characterized in that, during the pressure reduction control, the current value of the indicated current value is the value obtained by subtracting the first pressure reduction amount from the previous value of the indicated current value.

4. The control unit, When it is determined that the second brake operator has been released, if the current value indicated to the pressure regulating valve is less than the threshold, a second pressure reduction amount smaller than the first pressure reduction amount is set. The vehicle brake control device according to claim 3, characterized in that, during the pressure reduction control, the current value of the indicated current value is the value obtained by subtracting the second pressure reduction amount from the previous value of the indicated current value.

5. A first brake operator connected to the first brake, A second brake that cannot be operated by the first brake control, A second brake lever connected to the second brake, A control unit capable of performing braking force control, which controls the braking force of the first brake based on the operation of the second brake operator, A vehicle brake control device comprising: a hydraulic unit that generates braking force of the first brake by applying hydraulic pressure to the first brake, the hydraulic unit having a pressure regulating valve that changes the hydraulic pressure applied to the first brake according to the value of an indicated current value, The control unit, During the aforementioned braking force control, Pressurization control controls the braking force of the first brake by controlling the pressure regulating valve based on the operation of the second brake operator, A release determination is made to determine whether the second brake lever was released during the pressurization control, If the release determination determines that the second brake operator has been released, the pressure regulating valve is controlled to gradually reduce the braking force of the first brake, and the following is performed: The system is configured to terminate the braking force control when the amount of operation of the second brake lever falls below a predetermined value during the execution of the braking force control. A vehicle brake control device characterized by gradually decreasing the instruction current value in accordance with the decrease in the amount of operation of the second brake lever, based on the instruction current value and the amount of operation when it is determined that the second brake lever has been released, such that the instruction current value becomes 0 when the amount of operation of the second brake lever reaches the predetermined value.

6. A first brake operator connected to the first brake, A second brake that cannot be operated by the first brake control, A second brake lever connected to the second brake, A vehicle brake control device comprising: a control unit capable of performing brake force control that controls the braking force of the first brake based on the operation of the second brake operator, The control unit, During the aforementioned braking force control, Pressurization control controls the braking force of the first brake based on the operation of the second brake operator, A release determination is made to determine whether the second brake lever was released during the pressurization control, If the release determination determines that the second brake lever has been released, a depressurization control is performed to gradually reduce the braking force of the first brake. A vehicle brake control device characterized in that, during the pressure reduction control, if the amount of operation of the second brake operator increases, the pressure control is restarted and the increase in braking force is limited so that the increase in braking force per unit time is less than or equal to an upper limit.

7. A first brake control element connected to the first brake, A second brake that cannot be operated by the first brake control, A second brake lever connected to the second brake, A brake control method using a vehicle brake control device comprising a control unit capable of performing brake force control that controls the braking force of the first brake based on the operation of the second brake operator, The control unit, A pressurizing step in which the braking force of the first brake is controlled based on the operation of the second brake operator, A release determination step is performed to determine whether or not the second brake operator was released during the pressurization step, A brake control method characterized by performing a decompression step in which, if it is determined in the release determination step that the second brake operator has been released, the braking force of the first brake is gradually reduced without controlling the second brake.

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