Brake fluid pressure control device for bar handle vehicles

Abstract

[Problem] The objective of the present invention is to achieve a cost reduction by adopting a configuration in which brake hold control can be implemented without providing a hydraulic unit for a driving wheel. [Solution] This brake fluid pressure control device for a bar handle vehicle comprises: a driving wheel side brake for braking a driving wheel; a driven wheel side brake for braking a driven wheel; a hydraulic unit for increasing, holding, and reducing a hydraulic pressure of the driven wheel side brake; and a control portion for controlling the hydraulic unit. The control portion executes brake hold control including: determining whether the bar handle vehicle is stopped (S1); and, if it is determined that a condition for maintaining the vehicle stop is satisfied (S2: Yes), performing pressure increase control (S3) to increase the hydraulic pressure of the driven wheel side brake, and holding control (S5) to hold the hydraulic pressure of the driven wheel side brake.

Description

[Technical Field]

[0001] The present invention relates to a brake fluid pressure control device for a bar-handle vehicle, which is equipped with a fluid pressure unit for increasing, maintaining, and reducing fluid pressure in wheel brakes. [Background technology]

[0002] Conventionally, a brake fluid pressure control device for a bar-handle vehicle is known that can execute brake hold control to increase and maintain brake pressure in the brake fluid pressure circuit of the rear wheel, which is the driving wheel, when the motorized two-wheeled vehicle is stopped and the brake operator is operated (see Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Special Publication No. 2009-539689 Summary of the Invention

[0004] However, in the conventional technology, brake hold control is performed on the drive wheels, so it is necessary to provide a hydraulic unit for the drive wheels, which increases costs.

[0005] SUMMARY OF THE INVENTION Therefore, an object of the present invention is to reduce costs by providing a configuration that allows brake hold control to be performed without providing a hydraulic unit for the drive wheels.

[0006] In order to solve the above-mentioned problems, the brake fluid pressure control device for a bar handle vehicle according to the present invention includes a driving wheel side brake for braking the driving wheels, a driven wheel side brake for braking the driven wheels, a fluid pressure unit for increasing, maintaining and reducing the fluid pressure of the driven wheel side brake, and a control unit for controlling the fluid pressure unit. When the control unit determines that the bar handle vehicle has stopped and that the conditions for maintaining the stop have been met, it executes brake hold control, which includes a pressurization control for increasing the hydraulic pressure of the driven wheel brake and a holding control for holding the hydraulic pressure of the driven wheel brake.

[0007] According to this configuration, brake hold control can be performed without providing a hydraulic unit for the drive wheels, thereby reducing costs.

[0008] Furthermore, the control unit may switch from the pressurization control to the holding control if it determines that a first condition has been met after executing the pressurization control, and may switch from the holding control to the pressurization control if it determines that a second condition has been met after executing the holding control.

[0009] According to this configuration, pressurization control and holding control are alternately switched, so that even if the hydraulic pressure drops slightly during holding control, pressurization control is subsequently executed, so that the hydraulic pressure of the driven wheel brake can be well maintained at a predetermined pressure.

[0010] The first condition may be that a first time has elapsed since the start of the pressurization control, and the second condition may be that a second time has elapsed since the start of the holding control.

[0011] According to this configuration, since the switching between the pressurization control and the holding control is performed based on time, a detection means such as a hydraulic pressure sensor is not required, and an inexpensive configuration can be achieved.

[0012] Furthermore, the control unit may reduce the hydraulic pressure of the driven wheel brake at a first gradient when a release condition for releasing the brake hold control is satisfied.

[0013] According to this configuration, when the brake hold control release condition is satisfied, the hydraulic pressure of the driven wheel brake is gradually reduced at the first gradient, thereby making it possible to prevent the driver from feeling uncomfortable.

[0014] In addition, the control unit may reduce the hydraulic pressure of the driven wheel brake at a second gradient greater than the first gradient when the accelerator operation amount is equal to or greater than a predetermined amount, or when the wheel speed or vehicle speed exceeds a predetermined threshold.

[0015] According to this configuration, when the driver intends to start, for example, when the accelerator pedal is operated by a predetermined amount or more, the hydraulic pressure of the driven wheel brake is reduced at a second gradient greater than the first gradient, so that the reduction in pressure is achieved quickly, allowing the vehicle to start smoothly.

[0016] In addition, the brake fluid pressure control device for a bar handle vehicle may further include a driven wheel side brake operator for operating the driven wheel side brake, and a drive wheel side brake operator for operating the drive wheel side brake, and the condition for maintaining the vehicle stopped may be that the operation of the drive wheel side brake operator is continued for a predetermined period of time or more.

[0017] By making the operation of the drive wheel side brake operator a condition for maintaining the vehicle stopped, it is possible to accurately determine whether the driver intends to maintain the vehicle stopped.

[0018] The control unit may also determine whether the drive wheel side brake operation element has been operated based on a signal from an angle sensor that detects an operation angle of the drive wheel side brake operation element.

[0019] According to this configuration, whether or not the drive wheel side brake operator has been operated is determined based on a signal from the angle sensor, so the configuration can be made cheaper than, for example, when determining the operation of the drive wheel side brake operator using another sensor.

[0020] The drive wheel brake may be a mechanical brake.

[0021] According to this configuration, by using a mechanical brake as the drive wheel side brake, the brake fluid pressure control device for a bar handle vehicle can be configured inexpensively. [Brief explanation of the drawings]

[0022] [Figure 1] 1 is a diagram showing the configuration of a motorcycle equipped with a brake fluid pressure control device for a bar handle vehicle according to an embodiment; [Figure 2] 10 is a flowchart showing the operation of a control unit. [Figure 3] 10 is a flowchart showing changes in each parameter after the brake hold control is started until the brake hold control is terminated due to the satisfaction of a release condition. [Figure 4] 10 is a flowchart showing changes in each parameter after the brake hold control is started until the brake hold control is terminated when a condition indicating an intention to start driving is satisfied. DETAILED DESCRIPTION OF THE INVENTION

[0023] Hereinafter, the embodiments will be described in detail with reference to the drawings as appropriate. As shown in FIG. 1, a motorcycle MC, which is an example of a bar handlebar vehicle, includes an engine ENG, a transmission TM, and a brake fluid pressure control device C for a bar handlebar vehicle.

[0024] 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.

[0025] 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. Here, the wheel speed sensor 51 is a sensor that generates a pulse wave in accordance with the rotation of the wheels.

[0026] The brake fluid pressure control device C for a bar handle vehicle includes a brake system BF for the front wheels WF, a brake system BR for the rear wheels WR, and a control unit 100.

[0027] The brake system BF is mainly composed of a front brake lever LF as an example of a driven wheel side brake operator, a master cylinder MF, a hydraulic unit 10, a front brake 20F as an example of a driven wheel side 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.

[0028] The front brake lever LF is an operating lever for actuating the front brake 20F, and is disposed on the right side of the handlebar of the motorcycle MC so that it can be operated by the rider's right hand. The master cylinder MF is a device that outputs hydraulic pressure according to the amount of operation of the front brake lever LF.

[0029] 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.

[0030] The hydraulic unit 10 is a unit for increasing, maintaining, and reducing the hydraulic pressure 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 having an oil passage (hydraulic pressure passage) through which brake fluid flows. Under normal circumstances, the oil passage from the input port 11a to the output port 11b of the pump body 11 is connected, so that the hydraulic pressure output from the master cylinder MF is transmitted to the front brake 20F.

[0031] The hydraulic line connecting the input port 11a and the output port 11b is provided with a pressure regulating valve 7, which is a normally open proportional solenoid valve that can adjust the difference in hydraulic pressure between the upstream and downstream sides in response to the supplied current. A check valve 7a is provided in parallel with the pressure regulating valve 7, which allows flow only to the output port 11b side.

[0032] 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.

[0033] 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.

[0034] 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.

[0035] 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.

[0036] 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.

[0037] 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. When excessive brake fluid pressure in the front brakes 20F needs to be reduced, such as during antilock 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 line 19B, thereby draining the brake fluid from the front brakes 20F. When the front brake lever LF is not being operated by the driver and the front brakes 20F are to be pressurized, 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.

[0038] The brake system BR is mainly composed of a rear brake lever LR as an example of a drive wheel side brake operator, an angle sensor 53, a rear brake 20R as an example of a drive wheel side brake, and a wire W connecting the rear brake lever LR and the rear brake 20R.

[0039] 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 angle sensor 53 is a sensor for detecting the operation angle of the rear brake lever LR.

[0040] The rear brake 20R is a brake that brakes 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 is, for example, a drum brake, and includes a drum 25 and a brake shoe and a return spring, which are not shown.

[0041] 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.

[0042] 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.

[0043] Specifically, the control unit 100 has a function of executing brake hold control, which includes pressurization control for increasing the hydraulic pressure of the front brake 20F and hold control for holding the hydraulic pressure of the front brake 20F. In pressurization control, the control unit 100 does not pass current to the inlet valve 1 and the outlet valve 2, but passes current corresponding to a command current value to the pressure regulating valve 7, thereby driving the motor 6. When the motor 6 is driven to open the intake valve 8 and execute pressurization control, the hydraulic pressure of the front brake 20F is pressurized to a predetermined pressure corresponding to the command current value to the pressure regulating valve 7, and then maintained at the predetermined pressure.

[0044] When switching from pressurization control to pressure holding control, the control unit 100 stops the motor 6 while maintaining the state of each solenoid valve in the state it was in during pressurization control. When the intake valve 8 is closed and pressure holding control is executed due to the stopping of the motor 6, the hydraulic pressure of the front brake 20F is maintained at a predetermined pressure corresponding to the command current value to the pressure regulating valve 7, following the pressurization control. When switching from pressure holding control to pressurization control, the control unit 100 drives the motor 6 while maintaining the state of each solenoid valve in the state it was in during pressure holding control. In other words, after executing pressurization control once, the control unit 100 switches between pressure holding control and pressurization control by switching the drive state of the motor 6.

[0045] The control unit 100 executes (starts) brake hold control when it determines that the motorcycle MC has stopped and that the conditions for maintaining the stop are satisfied. In this embodiment, the control unit 100 determines whether the motorcycle MC has stopped based on speed information acquired from the wheel speed sensor 51 or the speed detection sensor 52 and throttle opening information acquired from the throttle sensor 54. Here, the speed information may be the wheel speed or may be the vehicle speed calculated based on the wheel speed.

[0046] The control unit 100 determines that the motorcycle MC has stopped when the speed indicated by the speed information is equal to or less than the first speed and the throttle opening indicated by the throttle opening information is equal to or less than the first opening.

[0047] The first speed can be set to a value close to 0, for example, 0. The first opening can be set to a value close to 0, for example, 0. Hereinafter, the above-described conditions used for vehicle stop determination will also be referred to as vehicle stop conditions.

[0048] In this embodiment, the condition for maintaining the vehicle stopped is that the rear brake lever LR has been operated for a predetermined period of time or longer. The control unit 100 determines whether the rear brake lever LR has been operated based on a signal from the angle sensor 53. For example, the control unit 100 determines that the rear brake lever LR has not been operated when the operation angle acquired from the angle sensor 53 is equal to or smaller than a predetermined angle θth, and determines that the rear brake lever LR has been operated when the operation angle acquired from the angle sensor 53 is greater than the predetermined angle θth. Note that the predetermined angle θth can be, for example, an angle greater than 0 (see FIG. 3).

[0049] After executing the pressurization control, if the control unit 100 determines that a first condition is satisfied, the control unit 100 switches from the pressurization control to the holding control. In this embodiment, the first condition is defined as the passage of a first time period from the start of the pressurization control. Here, the first time period is equal to or longer than the time required for the hydraulic pressure of the front brake 20F to increase from 0 to a predetermined pressure through the pressurization control, and is determined appropriately through experiments, simulations, etc.

[0050] After executing the hold control, if the control unit 100 determines that a second condition is met, it switches from the hold control to the pressurization control. In this embodiment, the second condition is defined as the passage of a second time period since the start of the hold control. Here, the second time period is appropriately determined through experiments, simulations, etc., so that the hydraulic pressure of the front brake 20F does not decrease significantly even if the hydraulic pressure of the front brake 20F gradually decreases during the hold control due to, for example, the opening degree of the pressure regulator valve 7. Note that the first time period and the second time period may be different from each other or may be the same.

[0051] When a release condition for releasing the brake hold control is satisfied, the control unit 100 reduces the hydraulic pressure of the front brake 20F at a first gradient. In this embodiment, the release condition is that the rear brake lever LR is repeatedly gripped and then maintained for a predetermined time or longer, or that the aforementioned vehicle stop condition is not satisfied. Whether the rear brake lever LR has been repeatedly gripped can be determined by determining whether the rear brake lever LR, which is in an unoperated state, has been operated, for example, by determining whether the operating angle of the rear brake lever LR has increased from a zero state to a predetermined angle θth or greater. In this embodiment, the predetermined time for the release condition and the predetermined time for the aforementioned vehicle stop maintenance condition are the same, but these predetermined times may be different. When reducing the hydraulic pressure of the front brake 20F at a first gradient, the control unit 100 sets the states of the solenoid valves and motors to the same states as those in the hold control, and gradually reduces the magnitude of the command current value for the pressure regulator valve 7.

[0052] When the driver intends to start, the control unit 100 reduces the hydraulic pressure of the front brake 20F at a second gradient greater than the first gradient. Specifically, when the operation amount of the accelerator AC is equal to or greater than a predetermined amount, or when the wheel speed or the vehicle body speed exceeds a predetermined threshold, the control unit 100 reduces the hydraulic pressure of the front brake 20F at a second gradient greater than the first gradient. In this embodiment, the determination of whether the operation amount of the accelerator AC is equal to or greater than the predetermined amount is performed by determining whether the throttle opening information acquired from the throttle sensor 54 is equal to or greater than a second opening greater than the first opening described above. Furthermore, the determination of whether the wheel speed or the vehicle body speed has exceeded a predetermined threshold is performed by determining whether the speed information acquired from the wheel speed sensor 51 or the speed detection sensor 52 has exceeded a second speed greater than the first speed described above.

[0053] Furthermore, when reducing the hydraulic pressure of the front brake 20F at the second gradient, the control unit 100 sets the states of the solenoid valves and motors to the same states as in the holding control, and sets the command current value for the pressure regulating valve 7 to 0. Specifically, for example, the control unit 100 reduces the hydraulic pressure of the front brake 20F at the second gradient by stopping the supply of power to the solenoid valves and motors.

[0054] In addition, as a method for reducing the hydraulic pressure of the front brake 20F at the second gradient, a method may be used in which current is passed through the inlet valve 1 and the outlet valve 2, and no current is passed through the other solenoid valves, thereby releasing the hydraulic pressure from the outlet valve 2.

[0055] 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.

[0056] 2, the control unit 100 first determines whether the motorcycle MC has stopped (S1). If it is determined in step S1 that the motorcycle MC has stopped (Yes), the control unit 100 determines whether the operation of the rear brake lever LR has continued for a predetermined time or longer (S2). If it is determined No in step S1 or step S2, the control unit 100 ends this process.

[0057] If it is determined in step S2 that the operation has continued for a predetermined time or longer (Yes), the control unit 100 starts pressurization control (S3). After step S3, the control unit 100 determines whether a first time has elapsed since the start of pressurization control (S4).

[0058] If it is determined in step S4 that the first time period has not elapsed (No), the control unit 100 determines whether the cancellation condition is met or whether the driver intends to start driving (S7). If it is determined in step S7 that the cancellation condition is not met and the driver does not intend to start driving (No), the control unit 100 returns to the processing of step S3 and continues the pressurization control. If it is determined in step S4 that the first time period has elapsed (Yes), the control unit 100 starts the holding control (S5).

[0059] After step S5, the control unit 100 determines whether a second time has elapsed since the start of the pressure holding control (S6). If it is determined in step S6 that the second time has elapsed (Yes), the control unit 100 returns to step S3 and starts the pressure holding control. If it is determined in step S6 that the second time has not elapsed (No), the control unit 100 determines whether the cancellation condition is met or whether the driver intends to start driving (S8).

[0060] If it is determined in step S8 that the cancellation condition is not satisfied and there is no intention to start, the control unit 100 returns to the process of step S6 and continues the hold control. If it is determined as Yes in step S7 or step S8, the control unit 100 determines whether or not the driver has the intention to start, that is, whether or not the condition for terminating the brake hold control is the condition for the intention to start (S9).

[0061] If it is determined in step S9 that the condition for terminating the brake hold control is not the condition of intention to start (No), the condition for terminating the brake hold control is the release condition, so the control unit 100 gradually reduces the hydraulic pressure in the front brake 20F at a first gradient (S10) and ends this process.If it is determined in step S9 that the condition for terminating the brake hold control is the condition of intention to start (Yes), the control unit 100 suddenly reduces the hydraulic pressure in the front brake 20F at a second gradient (S11) and ends this process.

[0062] Next, a specific example of the operation of the control unit 100 will be described in detail. As shown in FIG. 3, when the rider operates the rear brake lever LR while the motorcycle MC is stopped (time t1), and the operating angle of the rear brake lever LR becomes equal to or greater than a predetermined angle θth (time t2), the control unit 100 determines that the rear brake lever LR has been operated.

[0063] When the time during which the operating angle is equal to or greater than the predetermined angle θth exceeds the predetermined time Tth (time t3), the control unit 100 starts pressure application control, which increases the hydraulic pressure of the front brake 20F.

[0064] When the first time T1 has elapsed since the start of the pressurization control (time t4), the control unit 100 switches from pressurization control to holding control, thereby holding the hydraulic pressure of the front brake 20F.

[0065] When the second time T2 has elapsed since the start of the holding control (time t5), the control unit 100 starts the pressurization control again. Thereafter, the holding control and the pressurization control are alternately executed in the same manner as time passes (times t6 and t7).

[0066] When the driver releases the rear brake lever LR during brake hold control (time t21), the operating angle of the rear brake lever LR decreases and becomes 0 (time t4). When the driver grips the rear brake lever LR again (time t22), the operating angle of the rear brake lever LR increases.

[0067] During brake hold control, when the operating angle of the rear brake lever LR becomes equal to or greater than a predetermined angle θth from a state of 0 and a predetermined time Tth has elapsed (time t8), the control unit 100 gradually reduces the hydraulic pressure in the front brake 20F at a first gradient G1. As shown in Fig. 4, if the driver intends to start the vehicle by operating the accelerator AC during brake hold control (time t41), the control unit 100 suddenly reduces the hydraulic pressure in the front brake 20F at a second gradient G2 that is larger than the first gradient G1.

[0068] As described above, the following effects can be obtained in this embodiment. Since brake hold control can be performed without providing a hydraulic unit for the rear wheels WR, which are the drive wheels, costs can be reduced.

[0069] Since pressure increase control and pressure holding control are alternately switched, even if the hydraulic pressure drops slightly during pressure holding control, pressure increase control is then executed, so that the hydraulic pressure of the front brake 20F can be well maintained at a predetermined pressure.

[0070] Since the switching between the pressurization control and the holding control is performed based on time, a detection means such as a hydraulic pressure sensor is not required, and an inexpensive configuration can be achieved.

[0071] When the brake hold control release condition is met, the hydraulic pressure of the front brake 20F is gradually reduced at the first gradient G1, thereby making it possible to prevent the driver from feeling uncomfortable.

[0072] When the driver intends to start, the hydraulic pressure of the front brake 20F is reduced at a second gradient G2 that is greater than the first gradient G1, so that the pressure is reduced quickly and the motorcycle MC can be started smoothly.

[0073] By making the operation of the rear brake lever LR a condition for maintaining a stopped vehicle, it is possible to accurately determine whether the driver intends to maintain a stopped vehicle.

[0074] Whether or not the rear brake lever LR has been operated is determined based on a signal from the angle sensor 53, so the configuration can be made more inexpensive than when, for example, the operation of the rear brake lever is determined using another sensor.

[0075] Since the rear brake 20R is a mechanical brake, the brake fluid pressure control device C for a bar handle vehicle can be constructed inexpensively.

[0076] 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, the same reference numerals are used to designate components having substantially the same structures as those in the above-described embodiment, and the description thereof will be omitted.

[0077] The bar handle vehicle is not limited to a motorcycle MC, but may be any vehicle that is operated with a bar handle, such as a three-wheeled vehicle or a four-wheeled vehicle.

[0078] In the above embodiment, the rear wheels WR are the driving wheels and the front wheels WF are the driven wheels, but for example, the front wheels may be the driving wheels and the rear wheels may be the driven wheels.

[0079] The condition for maintaining the vehicle stopped is not limited to the condition shown in the above embodiment, but may be, for example, a condition that the operation of the brake operator on the driven wheel side is continued for a predetermined time or more.

[0080] The first and second conditions are not limited to those described in the above embodiment. The first condition may be, for example, that the hydraulic pressure of the driven wheel brake is equal to or greater than a first threshold, and the second condition may be, for example, that the hydraulic pressure of the driven wheel brake is less than a second threshold that is smaller than the first threshold. In this case, a hydraulic pressure sensor for detecting the hydraulic pressure of the driven wheel brake may be provided.

[0081] The brake operator is not limited to a lever, but may be, for example, a foot brake pedal.

[0082] The drive wheel brakes may be hydraulic brakes, and in this case, costs can be reduced by not providing a hydraulic unit for the drive wheel brakes.

[0083] The intake valve may be a normally closed solenoid valve.

[0084] The elements described in the above-described embodiment and modified examples may be implemented in any combination.

Claims

1. a drive wheel side brake for braking a drive wheel, a driven wheel side brake for braking a driven wheel, a hydraulic pressure unit for increasing, maintaining and reducing hydraulic pressure in the driven wheel side brake, a control unit for controlling the hydraulic pressure unit, a driven wheel side brake operator for operating the driven wheel side brake, and a drive wheel side brake operator for operating the drive wheel side brake, The control unit When it is determined that the bar handle vehicle has stopped and that a condition for maintaining the stop is satisfied, a brake hold control is executed, which includes a pressure increase control for increasing the hydraulic pressure of the driven wheel side brake and a pressure hold control for holding the hydraulic pressure of the driven wheel side brake, 10. A brake fluid pressure control device for a bar-handle vehicle, wherein the condition for maintaining the vehicle stopped is that the operation of the drive wheel side brake operator is continued for a predetermined period of time or more.

2. The control unit After performing the pressurization control, if it is determined that a first condition is satisfied, the pressurization control is switched to the holding control; 2. The brake fluid pressure control device for a bar-handle vehicle according to claim 1, wherein, after the holding control is executed, if it is determined that a second condition is satisfied, the holding control is switched to the pressurizing control.

3. the first condition is that a first time has elapsed since the start of the pressurization control, 3. The brake fluid pressure control device for a bar-handle vehicle according to claim 2, wherein the second condition is that a second time has elapsed since the start of the brake fluid pressure holding control.

4. 2. The brake fluid pressure control device for a bar-handle vehicle according to claim 1, wherein the control unit reduces the fluid pressure of the driven wheel brake at a first gradient when a release condition for releasing the brake hold control is satisfied.

5. The control unit 5. The brake fluid pressure control device for a bar-handle vehicle according to claim 4, wherein when an accelerator operation amount is equal to or greater than a predetermined amount, or when a wheel speed or a vehicle body speed exceeds a predetermined threshold, the fluid pressure of the driven wheel brake is reduced at a second gradient greater than the first gradient.

6. The control unit 2. The brake fluid pressure control device for a bar-handle vehicle according to claim 1, wherein whether or not the drive wheel side brake operator has been operated is determined based on a signal from an angle sensor that detects the operation angle of the drive wheel side brake operator.

7. 7. The brake fluid pressure control device for a bar handle vehicle according to claim 1, wherein the drive wheel brake is a mechanical brake.

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