Brake control device for vehicles with bar handle

A brake fluid pressure control device for vehicles with bar handle which is configured to start a holding control of a fluid pressure of a wheel brake according to wheel deceleration calculated based on a wheel speed of the vehicle is provided. In the brake fluid pressure control device, the vehicle includes an acceleration sensor which is configured to detect acceleration in a front-rear direction of the vehicle, acceleration, detected by the acceleration sensor, which occurs in a rearward direction when the vehicle is decelerating is detected as a positive value, and the holding control is started when it is judged that the acceleration detected by the acceleration sensor is larger than or equal to a detection acceleration threshold value and the wheel deceleration is smaller than or equal to a wheel deceleration threshold value.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority from Japanese Patent Application No. 2017-048868, filed on Mar. 14, 2017, the entire subject matter of which is incorporated herein by reference.

TECHNICAL FIELD

The present invention relates to a brake control device for vehicles with bar handle that controls braking of a vehicle with bar handle.

BACKGROUND

In vehicles with bar handle such as a motorcycle (hereinafter, also referred to merely as vehicle), fluid pressure control to reduce, raise or hold the brake fluid pressure by a brake control device for vehicles with bar handle is performed. Examples of the fluid pressure control include ABS (antilock-braking-system) control to suppress a slip of a wheel at the time of braking of the vehicle. In the system disclosed in Japanese Patent No. 2584587, when the inclined attitude angle (bank angle) of a motorcycle is larger than or equal to a predetermined threshold value, holding control to hold the braking pressure of the wheel before the lock pressure of the wheel is reached is performed as the ABS control.

However, in this type of vehicles with bar handle, if the holding control is performed in the neighborhood of a pressure at which the front wheel is locked during cornering, there is a possibility that the bank angle of the vehicle body unnaturally changes to make the behavior of the vehicle body unstable. That is, in the braking during cornering, appropriate holding control considering the bank angle of the vehicle body is required.

SUMMARY

The present invention is made in view of the above-mentioned circumstances, and an object thereof is to provide a brake control device for vehicles with bar handle capable of improving the stability of a vehicle with bar handle by performing the holding control at an appropriate time according to the bank angle at the time of cornering.

According to an aspect of the invention, there is provided a brake control device for vehicles with bar handle which is configured to perform a holding control to hold a brake fluid pressure that acts on a vehicle brake of a wheel of the vehicle, the brake control device comprising: a bank angle obtaining unit which is configured to obtain a bank angle of the vehicle; a deceleration obtaining unit which is configured to obtain a deceleration of the wheel; and a control unit which is configured to start the holding control when the deceleration reaches a holding control threshold value, the control unit which is configured to correct the holding control threshold value to a low deceleration side when the obtained bank angle increases.

DETAILED DESCRIPTION

Hereinafter, citing a preferred embodiment, a brake control device for vehicles with bar handle according to the present invention will be described in detail with reference to the attached drawings.

As shown inFIG. 1, a brake control device10according to the embodiment of the present invention is mounted on a vehicle with bar handle12, and controls the operation of a brake system14(wheel brake). Hereinafter, for convenience of explanation, the brake control device10will be referred to merely as control device10. Moreover, as the vehicle with bar handle12(vehicle12), a motorcycle, a motor tricycle and the like are cited, and in the following, description will be given with a motorcycle as an example.

The control device10performs the fluid pressure control (ABS control: reduction, raising or holding of the brake fluid pressure) as required. This fluid pressure control includes the holding control (ABS control) to suppress a slip of a wheel18by appropriately controlling the braking forces of the front wheel and the rear wheel by holding the brake fluid pressure applied to the wheel18.

In particular, the control device10according to the present embodiment improves the stability of the vehicle12in the cornering state by enabling the holding control to be performed at an early stage when a brake operation is performed by the driver while the vehicle12is cornering. In the following, for the facilitation of understanding of this control device10, first, the vehicle12and the brake system14will be described.

The vehicle12is provided with a vehicle body16and the wheel18(a front wheel18F, a rear wheel18R). The vehicle body16is provided with a traveling driving device (not shown) such as an engine that drives the rear wheel18R, and is provided with a bar handle20with which the driver operates the traveling direction of the vehicle12. The vehicle12turns in a desired direction by the bar handle20being operated or the vehicle body16itself being inclined by the driver.

The brake system14appropriately brakes the front wheel18F and the rear wheel18R under the control of the control device10. This brake system14includes the control device10, a front wheel brake22F, a rear wheel brake22R, a brake lever24, a brake pedal26, a first master cylinder28and a second master cylinder30. And a fluid pressure system34of the brake fluid pressure formed of brake fluid piping32and the control device10is provided between the front wheel brake22F and the first master cylinder28and between the rear wheel brake22R and the second master cylinder30.

The front wheel brake22F is provided with a front wheel disk36F attached to the front wheel18F to rotate together with the front wheel18F and a front wheel caliper38F that causes a pad (not shown) sandwiching the front wheel disk36F by the brake fluid pressure to proceed and recede. Likewise, the rear wheel brake22R is provided with a rear wheel disk36R attached to the rear wheel18R to rotate together with the rear wheel18R and a rear wheel caliper38R that causes a pad (not shown) sandwiching the rear wheel disk36R by the brake fluid pressure to proceed and recede.

The brake lever24is provided on one side (right side inFIG. 1) of the bar handle20, and is connected to the first master cylinder28attached to the bar handle20similarly. The first master cylinder28applies to the fluid pressure system34a brake fluid pressure responsive to the operation force of the brake lever24by the driver.

The brake pedal26is provided in a predetermined position of the vehicle body16, and is connected to the second master cylinder30attached to the vehicle body16. The second master cylinder30applies to the fluid pressure system34a brake fluid pressure responsive to the pressing operation force of the brake pedal26by the driver.

The piping32of the fluid pressure system34includes first piping32F1connecting between the first master cylinder28and the control device10, front wheel brake piping32F2between the control device10and the front wheel brake22F, second piping32R1connecting between the second master cylinder30and the control device10, and rear wheel brake piping32R2connecting between the control device10and the rear wheel brake22R.

The control device10is provided with a fluid pressure unit42and an ECU (electric control unit)44that controls the fluid pressure unit42. Inside the fluid pressure unit42, a fluid passage40constituting the fluid pressure system34by brake fluid channels and various parts is provided. To the input port and the output port of the fluid pressure unit42, the first piping32F1, the front wheel brake piping32F2, the second piping32R1and the rear wheel brake piping32R2are connected.

As shown inFIG. 2, the fluid passage40is provided with a front wheel brake channel41F making the first piping32F1and the front wheel brake piping32F2communicate with each other and a rear wheel brake channel41R making the second piping32R1and the rear wheel brake piping32R2communicate with each other. The front wheel brake channel41F and the rear wheel brake channel41R are basically formed so as to be the same, and in the following description, the structure of the front wheel brake channel41F will be described representatively.

In appropriate positions of the front wheel brake channel41F, an inlet valve46F (an inlet valve46R on the rear wheel brake channel41R), an outlet valve48F (an outlet valve48R on the rear wheel brake channel41R), a check valve50, a reservoir52, a suction valve54, a pump56, a discharge valve58, an orifice60and the like are provided. Moreover, the front wheel brake channel41F has five fluid channels61,62,63,64and65.

To lead the brake fluid pressure to the inlet valve46F, the channel61establishes communication from the input port to which the first piping32F1on the side of the first master cylinder28is connected, to one end of the inlet valve46F.

The channel62establishes communication from the other end of the inlet valve46F to the outlet port to which the front wheel brake piping32F2on the side of the front wheel caliper38F is connected.

The channel63establishes communication from the channel61to the reservoir52. The channel63is provided with the outlet valve48F.

The channel64establishes communication from the reservoir52to the suction side of the pump56. The channel65establishes communication from the discharge side of the pump56to the channel61. The channel65is provided with the orifice60.

The inlet valve46F is a normally open electromagnetic valve, and is provided between the first master cylinder28and the front wheel caliper38F (between the channel61and the channel62). The inlet valve46F allows the transmission of the brake fluid pressure from the first master cylinder28to the front wheel caliper38F by being open in normal times when the ABS control (fluid pressure control) is not started. On the other hand, the inlet valve46F shuts off the brake fluid pressure applied from the brake lever24to the front wheel brake22F through the first master cylinder28by being closed when the front wheel18F is about to slip in the ABS control.

The outlet valve48F is a normally closed electromagnetic valve, and is provided between the front wheel caliper38F and the reservoir52(the channel63). The outlet valve48F, which is closed when the ABS control is inactive, makes the brake fluid pressure applied to the front wheel brake22F escape to the reservoir52by being opened when the front wheel18F is about to slip in the ABS control.

The check valve50is a valve that allows only the inflow of the brake fluid from the front wheel caliper38F to the first master cylinder28, and is connected in parallel to the inlet valve46F. Thereby, when the input of the fluid pressure from the first master cylinder28is released, even if the inlet valve46F is closed, the flow of the brake fluid from the side of the front wheel caliper38F to the first master cylinder28is allowed.

The reservoir52stores the brake fluid that flows by the outlet valve48F being opened. The pump56is provided with the suction valve54and the discharge valve58, is operated by a motor M provided inside the fluid pressure unit42, and has the function of sucking the brake fluid stored in the reservoir52and returning (discharging) the brake fluid to the side of the first master cylinder28. Moreover, the orifice60absorbs the pulsation of the brake fluid discharged to the side of the first master cylinder28through the discharge valve58.

As shown inFIGS. 1 and 2, the vehicle12is provided with a front wheel speed sensor66F that detects the speed (front wheel speed FV) of the front wheel18F and a rear wheel speed sensor66R that detects the speed (rear wheel speed RV) of the rear wheel18R. Hereinafter, the front wheel speed sensor66F and the rear wheel speed sensor66R are collectively referred to also as wheel speed sensors66. The wheel speed sensors66are communicably connected to the control device10through communication lines69. InFIGS. 1 and 2, the channels of the brake fluid are drawn by the thick solid lines, and the communication lines69that transmit signals of sensors and the like are drawn by the thin solid lines.

Further, the vehicle12is provided with a bank angle sensor68that detects a bank angle θ which is the inclined state of the vehicle12. In the present embodiment, the bank angle sensor68is structured as a sensor group formed of a combination of an acceleration sensor68aand an angular speed sensor68battached to the vehicle12. The bank angle sensor68is not limited to this structure but a known sensor may be applied; for example, a known inclination angle sensor may be applied.

As the acceleration sensor68a, a sensor capable of detecting an acceleration of not less than three axes is applied, and in the present embodiment, the acceleration sensor68ahas the function of detecting an acceleration applied in the horizontal direction (width direction) at least in a front view of the vehicle body16. Moreover, as the angular speed sensor68b, a gyroscope sensor that detects a roll angular speed and a yaw angular speed as the angular speed of the vehicle body16is applied. The acceleration sensor68aand the angular speed sensor68bare communicably connected to the control device10through the communication lines69.

The ECU44of the brake system14(the control device10) is structured as a computer (including a microcontroller) provided with a non-illustrated processor, memory and input-output interface. The ECU44is structured as the control unit of the present embodiment for controlling the operation of the fluid pressure unit42by the processor arithmetically processing a program stored in the memory. In particular, the ECU44performs the fluid pressure control to suppress a slip by appropriately adjusting the brake fluid pressure when it is determined that the wheel18is about to slip by the braking force in a state where the vehicle12is cornering at a curve or the like on a traveling road.

As shown inFIG. 3, the driver inclines the attitude of the vehicle body16rightward or leftward when the vehicle12turns to the right or the left. Thereby, a force in the horizontal direction is applied to the vehicle12according to the bank angle θ. When the driver's braking operation is performed while the vehicle12is cornering, the vehicle12decelerates to cause a deceleration, so that a force in the front-back direction is applied in a manner so as to be combined with the force in the horizontal direction.

The ECU44is structured so as to suppress a slip of the wheel18by adjusting the brake fluid pressure when a brake operation is performed by the driver during cornering and the wheel18is about to slip.

For this reason, as shown inFIG. 4, a wheel speed obtaining unit70, a wheel deceleration calculation unit72, a bank angle obtaining unit74, a cornering state discrimination unit76, a threshold value setting unit78, a determination unit80and a valve control unit82are provided inside the ECU44.

The wheel speed obtaining unit70receives the detection value from the wheel speed sensor66(the front wheel speed sensor66F, the rear wheel speed sensor66R). Then, the wheel speed obtaining unit70temporarily stores the received detection value in the memory as information on the front wheel speed FV and the rear wheel speed RV, and outputs the front wheel speed FV and the rear wheel speed RV to the wheel deceleration calculation unit72.

The wheel deceleration calculation unit72is the deceleration obtaining unit for calculating the deceleration of the wheel18, and is capable of obtaining the deceleration by differentiating the wheel speed of the wheel18(calculating the change rate of a predetermined time interval). In the present embodiment, the wheel deceleration calculation unit72calculates a front wheel deceleration FA actually applied to the front wheel18F from the front wheel speed FV and calculates a rear wheel deceleration RA actually applied to the rear wheel18R from the rear wheel speed RV. The deceleration obtaining unit may obtain the deceleration based on a different method (detection of the acceleration sensor, etc.).

Receiving a detection value Sa of the acceleration sensor68aand a detection value Sb of the angular speed sensor68b, the bank angle obtaining unit74calculates the bank angle θ which is the inclined attitude of the vehicle body16from these detection values Sa and Sb. In this case, the bank angle obtaining unit74calculates the bank angle θ by combining the acceleration applied in the horizontal direction of the vehicle12contained in the detection value Sa and the components of the roll angular speed and the yaw angular speed contained in the detection value Sb. Then, the bank angle obtaining unit74temporarily stores the calculated bank angle θ in the memory and outputs the bank angle θ to the cornering state discrimination unit76and the threshold value setting unit78.

The cornering state discrimination unit76discriminates the cornering state or the straightly traveling state of the vehicle12, or the like based on the received bank angle θ. The cornering state discrimination unit76has an angle threshold value (not shown) corresponding to the bank angle θ, and discriminates the cornering state of the vehicle12when the bank angle θ is larger than or equal to a predetermined angle threshold value and the state continues for a predetermined time. On the other hand, the cornering state discrimination unit76discriminates the straightly traveling state of the vehicle12when the bank angle θ is less than the predetermined angle threshold value or the state where the bank angle θ is larger than or equal to the predetermined angle threshold value is canceled immediately.

The threshold value setting unit78is set a holding control threshold value Th for determining whether to perform the holding control (ABS control) of the brake system14during cornering or not. That is, the holding control is performed by comparing and determining the holding control threshold value Th with the front wheel deceleration FA or the rear wheel deceleration RA at the determination unit80described later. For this reason, the holding control threshold value Th is set by a value corresponding to the deceleration (minus acceleration).

Inside the threshold value setting unit78, a storage unit78a(the storage area of the memory) storing a bank angle/correction amount map84is provided. As shown inFIG. 5, the bank angle/correction amount map84can be shown in a graphic form with the horizontal axis as the bank angle θ and the vertical axis as the correction amount. The correction line84ainFIG. 5is set so that when the bank angle θ is in a range from 0 degrees to a bank angle threshold value α, the correction amount is 0 and when the bank angle θ is larger than or equal to the bank angle threshold value α, the correction amount linearly increases as the bank angle θ increases. The association function of the bank angle θ and the correction amount may be arbitrarily designed; for example, the bank angle θ and the correction amount may be associated nonlinearly (in a polynomial function) by experiment or the like.

The threshold value setting unit78stores in the storage unit78aan initial threshold value Th0of the holding control threshold value Th when the bank angle θ is 0 degrees, that is, when the vehicle12is in the straightly traveling state. This initial threshold value Th0is a predetermined value for starting the holding control when a deceleration occurs in the straightly traveling state of the vehicle12. At the time of cornering, when the correction amount is set with the bank angle θ as the argument, the threshold value setting unit78calculates a threshold value after correction (corrected threshold value Th1) moved to the low deceleration side by adding this correction value to the initial threshold value Th0. Since the corrected threshold value Th1is lower in deceleration than the initial threshold value Th0, when the deceleration increases by the brake operation during cornering, the holding control can be started at an early stage.

That is, as the holding control threshold value Th, when the bank angle θ is lower than the bank angle threshold value α, the threshold value setting unit78outputs the initial threshold value Th0, and when the bank angle θ is larger than or equal to the bank angle threshold value α, the threshold value setting unit78outputs the corrected threshold value Th1corrected according to the bank angle θ.

The determination unit80compares the actual deceleration of the front wheel18F (the front wheel deceleration FA) with the received holding control threshold value Th (the initial threshold value Th0, the corrected threshold value Th1) to determine in what state the front wheel deceleration FA is in with respect to the holding control threshold value Th. Specifically, when the front wheel deceleration FA becomes higher in deceleration than the holding control threshold value Th (acceleration lower than the holding control threshold value Th), the start of the holding control is determined.

On the other hand, receiving the result of the determination by the determination unit80, the valve control unit82performs opening and closing of the inlet valve46F and the outlet valve48F of the fluid pressure unit42. In this case, the valve control unit82switches opening and closing of these valves individually by the pulse outputs to the inlet valve46F and the outlet valve48F.

For example, the valve control unit82holds the brake fluid pressure (caliper pressure) applied to the front wheel caliper38F by closing the normally open inlet valve46F when the start of the holding control is determined by the determination unit80. Moreover, in the holding control, the brake fluid pressure may be temporarily raised after the elapse of a certain period of time. In this case, the valve control unit82opens the inlet valve46F to thereby allow again the transmission of the brake fluid pressure to the front wheel caliper38F.

When a slip is about to occur on the wheel18even though the holding control is performed, by opening the normally closed outlet valve48F, the brake fluid is made to escape to the reservoir52to reduce the pressure. Further, when a state where the front wheel deceleration FA is lower than the holding control threshold value Th is determined by the determination unit80, while the outlet valve48F is closed, the inlet valve46F is opened to raise the caliper pressure. Further, the valve control unit82re-performs the holding control when the front wheel deceleration FA becomes higher than the holding control threshold value Th again.

The ECU44has the threshold value setting unit78, the determination unit80and the valve control unit82also for the rear wheel18R as function portions similar to the above-described ones (the wheel speed obtaining unit70, the wheel deceleration calculation unit72, the bank angle obtaining unit74and the cornering state discrimination unit76are common). That is, the ECU44sets the holding control threshold value Th for the rear wheel18R based on the bank angle θ, and compares the holding control threshold value Th and the rear wheel deceleration RA to determine the execution of the holding control of the rear wheel18R. Therefore, the ECU44can optimize the overall braking force of the vehicle12by individually controlling the front wheel18F and the rear wheel18R when the vehicle12is cornering.

The control device10according to the present embodiment is basically structured as described above, and its operation and advantage will be described below. In the following operation description, the control on the front wheel18F will be representatively described similarly to the above.

The driver inclines the vehicle body16for cornering at a curve or the like on a traveling road while the vehicle12is traveling. Therefore, the bank angle θ of the vehicle body16varies during cornering. During the traveling of the vehicle12, as shown inFIG. 4, the bank angle obtaining unit74of the ECU44(the control device10) receives the detection values Sa and Sb from the acceleration sensor68aand the angular speed sensor68b, and steadily calculates the bank angle θ. Moreover, the cornering state discrimination unit76discriminates the cornering state or the straightly traveling state of the vehicle12based on the result of the detection of the bank angle θ. Then, when the cornering state discrimination unit76discriminates the cornering state, the threshold value setting unit78sets the holding control threshold value Th.

In this case, the threshold value setting unit78reads the bank angle/correction amount map84stored in the storage unit78a. Further, the threshold value setting unit78extracts the correction amount from the bank angle θ with reference to the bank angle/correction amount map84being read (see alsoFIG. 5). After extracting the correction amount, the threshold value setting unit78adds the correction amount to the initial threshold value Th0to calculate the corrected threshold value Th1, and outputs it to the determination unit80. Moreover, the holding control threshold value Th is consecutively updated according to the bank angle θ of the vehicle body16that changes during cornering.

On the other hand, the wheel speed obtaining unit70of the ECU44receives the front wheel speed FV and the rear wheel speed RV from the front wheel speed sensor66F and the rear wheel speed sensor66R. With this reception, the wheel deceleration calculation unit72calculates the front wheel deceleration FA from the front wheel speed FV, and outputs the front wheel deceleration FA to the determination unit80. The determination unit80compares the front wheel deceleration FA with the holding control threshold value Th (the initial threshold value Th0, the corrected threshold value Th1) to determine whether to perform the holding control or not.

At a time point t1, the driver pulls the brake lever24to cause a brake fluid pressure (master cylinder pressure) at the first master cylinder28, and the fluid pressure acts on the front wheel caliper38F to brake the front wheel disk36F. Consequently, the vehicle body16starts deceleration, and the front wheel deceleration FA calculated from the front wheel speed FV by the wheel deceleration calculation unit72also increases.

In this case, the determination unit80monitors the front wheel deceleration FA of the wheel deceleration calculation unit72, that is, performs comparison with the holding control threshold value Th. When determining at a time point t2that the front wheel deceleration FA has reached the holding control threshold value Th (is larger than or equal to the holding control threshold value Th inFIG. 6), the determination unit80instructs the valve control unit82to start the holding control. The determination unit80may perform time measurement after the front wheel deceleration FA is larger than or equal to the holding control threshold value Th and provide the instruction to perform the holding control based on the fact that the front wheel deceleration FA continues being larger than or equal to the threshold value for a predetermined time.

As the holding control, the valve control unit82closes the inlet valve46F transmitting the fluid pressure of the master cylinder pressure to the front wheel caliper38F by being normally open, based on the instruction to perform the holding control from the determination unit80. Thereby, after the time point t2, while the master cylinder pressure increases, the caliper pressure is maintained, so that mutual fluid pressures become non-linking.

In the present embodiment, the holding control threshold value Th is changed to the low deceleration side according to the bank angle θ. For this reason, when the front wheel18F decelerates while the vehicle12is cornering, the holding control can be started at an early stage. As a result, a slip of the front wheel18F can be suppressed.

Moreover, while the holding control is being performed, the ECU44temporarily opens the inlet valve46F at a time point t3when the front wheel deceleration FA becomes close to the holding control threshold value Th (the corrected threshold value Th1). Thereby, the caliper pressure of the front wheel caliper38F gently increases, so that a braking force can be applied to the front wheel18F. Thereafter, for example, similar processing is performed until the front wheel deceleration FA becomes lower than the holding control threshold value Th (becomes the low deceleration side), and when the front wheel deceleration FA becomes lower than the holding control threshold value Th (becomes the low deceleration side), the holding control is ended. In this case, the valve control unit82allows the flow of the brake fluid to the front wheel caliper38F by opening the inlet valve46F. Further, when the front wheel deceleration FA is lower than or equal to the holding control threshold value Th, the holding control is performed again.

The control of the rear wheel brake22R is also performed separately from the control of the front wheel brake22F, and processing similar to the above is performed.

As described above, the control device10according to the present embodiment can perform the holding control at an appropriate time by correcting the holding control threshold value Th to the low deceleration side when the bank angle θ which is the inclined state of the vehicle12during cornering increases. That is, when the holding control threshold value Th changes to the low deceleration side, the holding control can be started at a stage where the front wheel deceleration FA and the rear wheel deceleration RA are low. Thereby, when a braking operation is performed while the vehicle12is cornering, the braking force of the wheel18is suppressed (appropriately distributed) at an early stage. Consequently, the stability of the vehicle12at the time of cornering can be further improved.

In this case, the control device10can allow the bank angle θ in a minute operation such as a lane change by starting the correction of the initial threshold value Th0at a stage where the bank angle θ is larger than or equal to the bank angle threshold value α. And by increasing the correction amount as the bank angle θ increases, the holding control can be started at an earlier stage when the bank angle θ is large.

Moreover, the bank angle obtaining unit74can obtain a highly accurate bank angle θ by calculating the bank angle θ based on the acceleration in the horizontal direction of the vehicle12, the roll angular speed and the yaw angular speed. Consequently, the holding control can be performed at a more appropriate time. Further, by obtaining a highly accurate deceleration by calculating the front wheel deceleration FA from the front wheel speed FV (or the rear wheel deceleration RA from the rear wheel speed RV) as the deceleration of the vehicle12, the holding control can be performed at a far more appropriate time.

The present invention is not limited to the above-described embodiment and may be modified variously in accordance with the gist of the invention.

According to an aspect of the invention, there is provided a brake control device for vehicles with bar handle which is configured to perform a holding control to hold a brake fluid pressure that acts on a vehicle brake of a wheel of the vehicle, the brake control device comprising: a bank angle obtaining unit which is configured to obtain a bank angle of the vehicle; a deceleration obtaining unit which is configured to obtain a deceleration of the wheel; and a control unit which is configured to start the holding control when the deceleration reaches a holding control threshold value, the control unit which is configured to correct the holding control threshold value to a low deceleration side when the obtained bank angle increases.

According to the above, in the brake control device, when the bank angle which is the inclined state of the vehicle with bar handle being cornering increases, by correcting the holding control threshold value to the low deceleration side, the holding control can be performed at an appropriate time. That is, when the holding control threshold value changes to the low deceleration side, the holding of the braking pressure of the wheel can be started at a stage where the deceleration is low. Thereby, when a braking operation is performed while the vehicle with bar handle is cornering, the braking force of the wheel is distributed at an early stage and appropriately. Consequently, the stability of the vehicle with bar handle at the time of cornering can be further improved.

The control unit may be configured to start the correction of the holding control threshold value based on a fact that the bank angle is larger than or equal to a predetermined threshold value, and be configured to increase a correction amount of the holding control threshold value as the bank angle increases.

In the brake control device, by starting the correction of the holding control threshold value at a stage where the bank angle is larger than or equal to the predetermined threshold value, it can be suppressed that the holding control is performed at a bank angle in a minute operation such as a lane change. And by increasing the correction amount as the bank angle increases, the holding control can be started at an earlier stage when the bank angle is large.

The brake control device may further comprise a wheel speed obtaining unit which is configured to obtain a speed of the wheel from a wheel speed sensor that is configured to detect the speed of the wheel, and the deceleration obtaining unit may be configured to calculate the deceleration of the wheel based on the obtained speed of the wheel.

As described above, in the brake control device, by obtaining a highly accurate deceleration by calculating the deceleration of the wheel from the speed of the wheel as the deceleration of the vehicle with bar handle, the holding control can be performed at a far more appropriate time.

According to the present invention, the brake control device for vehicles with bar handle is capable of further improving the stability of the vehicle with bar handle by performing the holding control at an appropriate timing according to the bank angle at the time of cornering.