JP2021049858A - Brake device for vehicle - Google Patents

Abstract

To improve controllability of a pitching pose of a vehicle when the vehicle brakes.SOLUTION: A brake device 30 is applied to a vehicle 10 comprising a regeneration brake device 50 that adjusts regeneration brake force applied to at least one of a front wheel 11 and a rear wheel 12. The brake device 30 comprises: a friction brake device 31 that adjusts a front wheel friction brake force and a rear wheel friction brake force; and a control device 35. The control device 35 comprises: a distribution ratio derivation unit 353 that, based on a target of a pitching pose of the vehicle 10, derives a front/rear brake force distribution ratio and a friction/regeneration distribution ratio; and an operation instruction unit 354 that, based on a target vehicle brake force as well as the front/rear brake force distribution ratio and the friction/regeneration distribution ratio, instructs the friction brake device 31 and the regeneration brake device 50 to operate.SELECTED DRAWING: Figure 1

Description

The present invention relates to a vehicle braking device.

When braking the vehicle, the vehicle may pitch on the nose dive side. When the braking force applied to the front wheels is the front wheel braking force and the braking force applied to the rear wheels is the rear wheel braking force, the anti-dive force corresponding to the front wheel braking force acts on the vehicle body and becomes the rear wheel braking force. The corresponding anti-dive force acts on the vehicle body. Even if the braking force of the entire vehicle is the same, if the distribution ratio of the front wheel braking force and the rear wheel braking force changes, the anti-dive force and anti-lift force acting on the vehicle body change, and the pitching posture of the vehicle changes. Sometimes.

Patent Document 1 describes an example of a vehicle braking control device applied to a vehicle including a friction braking device and a regenerative braking device. In this device, when the distribution ratio of the front wheel braking force and the rear wheel braking force is changed while changing the regenerative braking force, a limit is set on the change speed of the regenerative braking force. As a result, the distribution ratio gradually changes, so that a sudden change in anti-dive force and anti-lift force can be suppressed. As a result, a sudden change in the pitching posture of the vehicle can be suppressed.

Japanese Unexamined Patent Publication No. 2015-139293

The point that the braking force acts on the wheel when the friction braking force is applied to the wheel and the point that the braking force acts on the wheel when the regenerative braking force is applied to the wheel are different from each other. Therefore, even if the magnitude of the braking force of the entire wheel is the same, the anti-dive force or anti-lift acting on the vehicle body depends on whether the friction braking force is applied to the wheel or the regenerative braking force is applied to the wheel. The power is different. Therefore, for example, when the regenerative braking force is replaced with the friction braking force or the friction braking force is replaced with the regenerative braking force, even if the speed of change of the regenerative braking force is limited as described above, the vehicle The pitching posture of the vehicle changes. That is, there is room for improvement in terms of improving the controllability of the pitching posture of the vehicle during vehicle braking.

The vehicle braking device for solving the above problems is applied to a vehicle provided with a regenerative braking device that adjusts a regenerative braking force applied to at least one of the front wheels and the rear wheels of the vehicle. This braking device includes a friction braking device that adjusts the friction braking force applied to the front wheels and the friction braking force applied to the rear wheels, and a control device that controls the braking force of the vehicle. The ratio of the braking force applied to the front wheels to the sum of the braking force applied to the front wheels and the braking force applied to the rear wheels is defined as the front-rear braking force distribution ratio, and the regenerative braking force of the front wheels and the rear wheels is defined as the regenerative braking force. The ratio of the friction braking force applied to the regeneration target wheel to the braking force applied to the regeneration target wheel, which is a wheel that can be applied, is defined as the friction regeneration distribution ratio. In this case, the control device has a distribution ratio deriving unit that derives the front-rear braking force distribution ratio and the friction regenerative distribution ratio based on the target of the pitching posture of the vehicle, and a target that is the target of the braking force of the vehicle. It is provided with an operation instruction unit that instructs the operation of the friction braking device and the regenerative braking device based on the vehicle braking force, the front-rear braking force distribution ratio, and the friction regeneration distribution ratio.

At the time of vehicle braking, at least one of friction braking force and regenerative braking force is applied to the wheel to be regenerated. Even if the total braking force applied to the wheels to be regenerated is the same, if the friction regeneration distribution ratio changes, the magnitude of the restraining force, which is the force for suppressing the pitching motion of the vehicle, changes. Therefore, if the friction regeneration distribution ratio changes, the pitching posture of the vehicle may change. When the front wheels are the wheels to be regenerated, the anti-dive force corresponds to the restraining force, while when the rear wheels are the wheels to be regenerated, the anti-lift force corresponds to the restraining force.

Further, if the front-rear braking force distribution ratio changes, the magnitudes of the anti-lift force and the anti-dive force change, so that the pitching posture of the vehicle may change.
According to the above configuration, the braking force applied to the front wheels and the braking force applied to the rear wheels are distributed so that the pitching posture of the vehicle approaches the target, and the friction braking force and the regenerative braking force are applied to the wheels to be regenerated. The distribution with and can be adjusted. This makes it possible to control the pitching posture of the vehicle when braking the vehicle.

The block diagram which shows typically a part of the vehicle which includes the braking device of the vehicle of 1st Embodiment. The graph which shows an example of the distribution of braking force. The schematic diagram which shows how the pitching posture of a vehicle changes at the time of vehicle braking. The schematic diagram explaining the anti-dive force when the friction braking force is applied to the front wheel. The schematic diagram explaining the anti-dive force when the regenerative braking force is applied to the front wheel. The flowchart explaining the processing routine which the control device of the braking device executes at the time of vehicle braking. The flowchart explaining the processing routine executed by the control device when calculating the friction regeneration distribution ratio of a wheel. A graph explaining a relational expression for calculating the friction regeneration distribution ratio of wheels. The block diagram which shows the outline of the hydraulic pressure generator in the braking device of the vehicle of 2nd Embodiment. The graph which shows the relationship between the operation amount of the braking operation member and the vehicle braking force. The flowchart explaining the part which derives the required pitching moment and the target pitch angle in the processing routine executed by the control device of the braking device. A map showing the relationship between the manipulated variable difference and the first correction value. A graph showing the relationship between the operating force input to the braking operating member and the vehicle braking force. A map showing the relationship between the difference in operating force and the second correction value. A graph showing the relationship between the operating force input to the braking operating member and the operating amount of the braking operating member. A map showing the relationship between the difference in operating force and the third correction value. In the vehicle braking device of the eighth embodiment, (a) and (b) are timing charts showing changes in the pitching moment correction value during vehicle braking. FIG. 5 is a flowchart illustrating a processing routine executed when a control device in the vehicle braking device of the ninth embodiment derives a pitching moment correction value. In the vehicle braking device of the tenth embodiment, (a) and (b) are timing charts showing how the distribution of braking force changes.

(First Embodiment)
Hereinafter, the first embodiment of the vehicle braking device will be described with reference to FIGS. 1 to 8.
FIG. 1 shows a part of a vehicle 10 provided with the braking device 30 of the present embodiment. The vehicle 10 includes a friction braking mechanism 20F for the front wheels 11 and a friction braking mechanism 20R for the rear wheels 12. In each of the friction braking mechanisms 20F and 20R, the higher the hydraulic pressure in the wheel cylinder 21, the stronger the friction material 23 is pressed against the rotating body 22 that rotates integrally with the corresponding wheels 11 and 12. By pressing the friction material 23 against the rotating body 22 in this way, braking force is applied to the wheels 11 and 12. In the following description, the braking force applied to the wheels 11 and 12 by the operation of the friction braking mechanisms 20F and 20R is referred to as "friction braking force", and the hydraulic pressure in the wheel cylinder 21 is referred to as "WC pressure".

The vehicle braking device 30 includes a friction braking device 31 that adjusts the friction braking force applied to the front wheels 11 and the friction braking force applied to the rear wheels 12 by controlling the WC pressure in each wheel cylinder 21, and the vehicle. It is provided with a control device 35 that controls the braking force. The friction braking device 31 has a hydraulic pressure generating device 32 and a braking actuator 33. The hydraulic pressure generator 32 generates hydraulic pressure according to the amount of operation when the braking operation member 321 such as the brake pedal is operated by the driver. Then, when the braking operation is performed by the driver, an amount of brake fluid corresponding to the hydraulic pressure generated by the hydraulic pressure generator 32 is supplied into each wheel cylinder 21. As a result, frictional braking force is applied to the wheels 11 and 12. The braking actuator 33 can individually adjust the friction braking force applied to the wheels 11 and 12 by individually controlling the WC pressure in each wheel cylinder 21. Each wheel cylinder 21 is attached to a suspension arm or a knuckle constituting the suspension, similarly to the wheels 11 and 12 and the rotating body 22. Therefore, the reaction force acting on the wheel cylinder 21 when the friction braking force is generated is directly transmitted to the suspension.

The vehicle 10 shown in FIG. 1 includes a motor generator 51F for the front wheels 11 and a motor generator 51R for the rear wheels 12. By making the motor generator 51F function as an electric motor, the driving force is transmitted from the motor generator 51F to the front wheels 11. On the other hand, by making the motor generator 51F function as a generator, braking force corresponding to the amount of power generated by the motor generator 51F is applied to the front wheels 11. Similarly, by making the motor generator 51R function as an electric motor, the driving force is transmitted from the motor generator 51R to the rear wheels 12. On the other hand, by making the motor generator 51R function as a generator, braking force corresponding to the amount of power generated by the motor generator 51R is applied to the rear wheels 12. In the following description, the braking force applied to the wheels 11 and 12 by the power generation of the motor generators 51F and 51R is referred to as "regenerative braking force". The motor generators 51F and 51R are attached to the vehicle body. Therefore, the reaction force acting on the motor generators 51F and 51R when the regenerative braking force is generated is transmitted to the vehicle body, and the reaction force is not directly transmitted to the suspension to which the wheels 11 and 12 are attached. ..

In the following description, the friction braking force applied to the front wheels 11 is referred to as a front wheel friction braking force, and the regenerative braking force applied to the front wheels 11 is referred to as a front wheel regenerative braking force. Further, the friction braking force applied to the rear wheels 12 is referred to as a rear wheel friction braking force, and the regenerative braking force applied to the rear wheels 12 is referred to as a rear wheel regenerative braking force.

The motor generators 51F and 51R are controlled by the motor control device 52. That is, in the present embodiment, the "regenerative braking device 50" that adjusts the front wheel regenerative braking force and the rear wheel regenerative braking force is configured by the motor generators 51F and 51R and the motor control device 52. Further, in the example shown in FIG. 1, the regenerative braking force can be applied to the front wheels 11 and the regenerative braking force can be applied to the rear wheels 12. Therefore, both the front wheels 11 and the rear wheels 12 are "regeneration target wheels".

Next, the control device 35 will be described.
As shown in FIG. 1, detection signals are input to the control device 35 from various sensors such as the manipulated variable detection sensor 101 and the vehicle speed sensor 102. The operation amount detection sensor 101 detects the operation amount SBP of the braking operation member 321 by the driver, and outputs a signal corresponding to the operation amount SBP as a detection signal. The vehicle speed sensor 102 detects the vehicle speed VS, which is the vehicle body speed of the vehicle, and outputs a signal corresponding to the vehicle speed VS as a detection signal.

Further, the control device 35 transmits and receives various information to and from the motor control device 52 of the regenerative braking device 50.
As shown in FIG. 1, the control device 35 has a required braking force derivation unit 351, a target setting unit 352, a distribution ratio derivation unit 353, an operation instruction unit 354, and a friction control unit 355 as functional units. are doing.

The required braking force deriving unit 351 derives the required vehicle braking force FxR, which is the braking force required for the vehicle 10. That is, when the braking operation member 321 is operated, the required braking force deriving unit 351 derives a value corresponding to the operation amount SBP of the braking operation member 321 as the required vehicle braking force FxR. For example, the required braking force deriving unit 351 increases the required vehicle braking force FxR as the operation amount SBP increases. Further, the required braking force deriving unit 351 derives the required vehicle braking force FxR even when the vehicle 10 is requested to decelerate in a situation where the braking operation is not performed.

The target setting unit 352 derives the target pitch angle APTr as the target of the pitching posture of the vehicle 10. The target pitch angle APTr is the target of the pitch angle AP of the vehicle 10. When the vehicle 10 is pitched to the nose dive side, the target pitch angle APTr becomes large. The setting process of the target pitch angle APTr will be described later.

The distribution ratio derivation unit 353 derives the front-rear braking force distribution ratio n, the friction regeneration distribution ratio nf of the front wheels 11, and the friction regeneration distribution ratio nr of the rear wheels 12. As each distribution ratio n, nf, nr, a value of "0" or more and "1" or less is derived. As shown in FIG. 2, the front-rear braking force distribution ratio n is the ratio of the front wheel braking force Fxf to the sum of the front wheel braking force Fxf and the rear wheel braking force Fxr. The front wheel braking force Fxf is the sum of the front wheel friction braking force Fxfb and the front wheel regenerative braking force Fxfd. The rear wheel braking force Fxr is the sum of the rear wheel friction braking force Fxrb and the rear wheel regenerative braking force Fxrd. The friction regeneration distribution ratio nf of the front wheels 11 is the ratio of the front wheel friction braking force Fxfb to the front wheel braking force Fxf. The friction regeneration distribution ratio nr of the rear wheels 12 is the ratio of the rear wheel friction braking force Fxrb to the rear wheel braking force Fxr. The derivation process of the front-rear braking force distribution ratio n and the friction regeneration distribution ratios nf and nr will be described later.

Returning to FIG. 1, the operation instruction unit 354 instructs the operation of the motor generators 51F and 51R of the regenerative braking device 50 and the operation of the braking actuator 33 of the friction braking device 31. That is, the operation instruction unit 354 derives the front wheel regenerative braking force required value FxfdR, which is the required value of the front wheel regenerative braking force Fxfd, and transmits information regarding the front wheel regenerative braking force required value FxfdR to the motor control device 52 of the regenerative braking device 50. To do. The operation instruction unit 354 derives the rear wheel regenerative braking force required value FxrdR, which is the required value of the rear wheel regenerative braking force Fxrd, and transmits information regarding the rear wheel regenerative braking force required value FxrdR to the motor control device 52. Further, the operation instruction unit 354 derives the front wheel friction braking force required value FxfbR, which is the required value of the front wheel friction braking force Fxfb, and the rear wheel friction braking force required value FxrbR, which is the required value of the rear wheel friction braking force Fxrb. ..

The friction control unit 355 operates the braking actuator 33 based on the front wheel friction braking force required value FxfbR and the rear wheel friction braking force required value FxrbR derived by the operation instruction unit 354. That is, the friction control unit 355 is provided for the rear wheels 12 while the WC pressure in the wheel cylinder 21 provided for the front wheels 11 becomes a hydraulic pressure corresponding to the front wheel friction braking force required value FxfbR. The braking actuator 33 is controlled so that the WC pressure in the wheel cylinder 21 is a hydraulic pressure corresponding to the rear wheel friction braking force required value FxrbR. As a result, the actual front wheel friction braking force Fxfb can be made substantially equal to the front wheel friction braking force required value FxfbR, and the actual rear wheel friction braking force Fxrb can be made substantially equal to the rear wheel friction braking force required value FxrbR.

Next, the motor control device 52 will be described.
As shown in FIG. 1, the motor control device 52 has a front wheel motor control unit 60F and a rear wheel motor control unit 60R as functional units. The front wheel motor control unit 60F controls the motor generator 51F, and the rear wheel motor control unit 60R controls the motor generator 51R.

The front wheel motor control unit 60F includes a front wheel side maximum regeneration acquisition unit 61F and a front wheel regeneration control unit 62F. The front wheel side maximum regenerative acquisition unit 61F acquires the maximum front wheel regenerative braking force FxfdMax, which is the maximum value of the regenerative braking force that can be applied to the front wheels 11 by driving the motor generator 51F at that time. For example, the front wheel side maximum regenerative acquisition unit 61F derives the maximum front wheel regenerative braking force FxfdMax based on the rotation speed of the front wheels 11, the amount of electricity stored in the vehicle-mounted battery that supplies electric power to the motor generator 51F, and the temperature.

The front wheel regenerative control unit 62F controls the amount of power generated by the motor generator 51F when adjusting the front wheel regenerative braking force Fxfd. That is, when the front wheel regenerative control unit 62F receives the information regarding the front wheel regenerative braking force required value FxfdR from the control device 35 of the braking device 30, the front wheel regenerative braking force required value FxfdR is compared with the maximum front wheel regenerative braking force FxfdMax. When the front wheel regenerative braking force required value FxfdR is equal to or less than the maximum front wheel regenerative braking force FxfdMax, the front wheel regenerative control unit 62F generates a power amount of the motor generator 51F so that the front wheel regenerative braking force Fxfd becomes equal to the front wheel regenerative braking force required value FxfdR. To control. On the other hand, the front wheel regenerative control unit 62F generates power from the motor generator 51F so that the front wheel regenerative braking force Fxfd becomes equal to the maximum front wheel regenerative braking force FxfdMax when the front wheel regenerative braking force required value FxfdR is larger than the maximum front wheel regenerative braking force FxfdMax. Control the amount. Then, the front wheel regenerative control unit 62F transmits information regarding the actual front wheel regenerative braking force Fxfd to the control device 35.

The rear wheel motor control unit 60R includes a rear wheel side maximum regeneration acquisition unit 61R and a rear wheel regeneration control unit 62R. The rear wheel side maximum regenerative braking force 61R acquires the maximum rear wheel regenerative braking force FxrdMax, which is the maximum value of the regenerative braking force that can be applied to the rear wheels 12 by driving the motor generator 51R at that time. For example, the rear wheel side maximum regenerative acquisition unit 61R derives the maximum rear wheel regenerative braking force FxrdMax based on the rotation speed of the rear wheels 12, the amount of electricity stored in the vehicle-mounted battery that supplies electric power to the motor generator 51R, the temperature, and the like.

The rear wheel regeneration control unit 62R controls the amount of power generated by the motor generator 51R when adjusting the rear wheel regeneration braking force Fxrd. That is, when the rear wheel regeneration control unit 62R receives the information regarding the rear wheel regenerative braking force required value FxrdR from the control device 35 of the braking device 30, the rear wheel regenerative braking force required value FxrdR and the maximum rear wheel regenerative braking force FxrdMax are set. Compare. When the rear wheel regenerative braking force required value FxrdR is equal to or less than the maximum rear wheel regenerative braking force FxrdMax, the rear wheel regeneration control unit 62R motors so that the rear wheel regenerative braking force Fxrd becomes equal to the rear wheel regenerative braking force required value FxrdR. The amount of power generated by the generator 51R is controlled. On the other hand, the rear wheel regeneration control unit 62R sets the rear wheel regeneration braking force Fxrd to be equal to the maximum rear wheel regeneration braking force FxrdMax when the rear wheel regeneration braking force required value FxrdR is larger than the maximum rear wheel regeneration braking force FxrdMax. The amount of power generated by the motor generator 51R is controlled. Then, the rear wheel regeneration control unit 62R transmits information regarding the actual rear wheel regeneration braking force Fxrd to the control device 35.

Next, with reference to FIG. 3, the pitching motion of the vehicle 10 during vehicle braking will be described. In FIG. 3, the spring load SWf on the front wheel 11 side and the spring load SWr on the rear wheel 12 side are represented by white arrows. The sprung load is a vertical load input from the vehicle body to the suspension by the vehicle weight and the pitching moment Mp.

When the vehicle 10 is decelerated by applying the braking force, a pitching moment Mp as shown by the solid arrow in FIG. 3 is generated in the vehicle 10, and the vehicle 10 makes a pitching motion toward the nose dive side. The nose dive is the behavior of the vehicle 10 that displaces the front part of the vehicle 10 downward and the rear part of the vehicle 10 upward. On the other hand, the behavior of the vehicle 10 that displaces the front portion of the vehicle 10 upward and the rear portion of the vehicle 10 downward is referred to as "nose lift". When the vehicle 10 pitches toward the nose dive side, the pitch angle AP of the vehicle 10 increases, while when the vehicle 10 pitches toward the nose lift side, the pitch angle AP decreases.

When the vehicle 10 pitches toward the nose dive side, the spring load SWf on the front wheel 11 side increases, so that the front wheel spring 15F constituting the suspension for the front wheel 11 contracts. As a result, as shown by the solid arrow in FIG. 3, the front wheel spring restoring force FSf, which is the restoring force of the front wheel spring 15F, is applied to the vehicle 10. Further, when the vehicle 10 pitches toward the nose dive side, the spring load SWr on the rear wheel 12 side becomes smaller, so that the rear wheel spring 15R constituting the suspension for the rear wheel 12 extends. As a result, as shown by the solid arrow in FIG. 3, the rear wheel spring restoring force FSr, which is the restoring force of the rear wheel spring 15R, is applied to the vehicle 10.

Further, as shown by the black arrows in FIG. 3, the vehicle 10 may generate an anti-dive force FAD and an anti-lift force FAL. The anti-dive force FAD is a force that displaces the front portion of the vehicle upward when a braking force is applied to the front wheels 11, and increases as the front wheel braking force Fxf increases. The anti-lift force FAL is a force that displaces the rear portion of the vehicle downward when a braking force is applied to the rear wheels 12, and increases as the rear wheel braking force Fxr increases.

The geometry of the suspension for the front wheels 11 and the suspension for the rear wheels 12 in the vehicle 10 shows that the anti-lift force FAL has a higher anti-dive force FAD than the anti-dive force FAD when the front wheel braking force Fxf and the rear wheel braking force Fxr have the same values. It may be set to be large. In the present embodiment, the anti-lift force FAL is assumed to be larger than the anti-dive force FAD.

Next, with reference to FIGS. 4 and 5, the magnitude relationship between the front wheel friction braking force Fxfb and the anti-dive force FAD and the magnitude relationship between the front wheel regenerative braking force Fxfd and the anti-dive force FAD will be described.

As shown in FIG. 4, when the front wheel 11 is subjected to the friction braking force, the contact point between the front wheel 11 and the road surface 150 corresponds to the action point P2 at which the front wheel friction braking force Fxfb acts on the front wheel 11. The center point P1 shown in FIG. 4 is the rotation center of the suspension for the front wheels 11. When the angle formed by the straight line L1 connecting the action point P2 and the center point P1 and the road surface 150 is set to the "front wheel action angle θfb", the component of the force acting on the center point P1 in the direction orthogonal to the road surface 150. The product of the front wheel side distance Lf, which is the distance from the center of gravity of the vehicle to the axle of the front wheel 11, corresponds to the anti-dive force FAD. That is, the anti-dive force FAD can be expressed as the following relational expression (Equation 1). As is clear from the relational expression (Equation 1), the larger the front wheel friction braking force Fxfb, the larger the anti-dive force FAD. Further, the larger the front wheel working angle θfb, the larger the anti-dive force FAD.

図５に示すように前輪１１に回生制動力が付与された場合、前輪１１の回転中心が、前輪回生制動力Ｆｘｆｄが前輪１１に作用する作用点Ｐ３に相当する。前輪１１用のサスペンションの中心点Ｐ１とこうした作用点Ｐ３を繋ぐ直線Ｌ２と路面１５０とのなす角を、「前輪作用角θｆｄ」とした場合、中心点Ｐ１に作用する力のうち、路面１５０と直交する方向の成分と前輪側距離Ｌｆとの積が、アンチダイブ力ＦＡＤに相当する。すなわち、アンチダイブ力ＦＡＤは、以下の関係式（式２）のように表すことができる。関係式（式２）からも明らかなように、前輪回生制動力Ｆｘｆｄが大きいほどアンチダイブ力ＦＡＤが大きくなる。また、前輪作用角θｆｄが大きいほどアンチダイブ力ＦＡＤが大きくなる。

When a regenerative braking force is applied to the front wheels 11 as shown in FIG. 5, the center of rotation of the front wheels 11 corresponds to a point of action P3 in which the front wheel regenerative braking force Fxfd acts on the front wheels 11. When the angle formed by the straight line L2 connecting the center point P1 of the suspension for the front wheel 11 and the action point P3 and the road surface 150 is set to the "front wheel action angle θfd", among the forces acting on the center point P1, the road surface 150 The product of the components in the orthogonal direction and the front wheel side distance Lf corresponds to the anti-dive force FAD. That is, the anti-dive force FAD can be expressed as the following relational expression (Equation 2). As is clear from the relational expression (Equation 2), the larger the front wheel regenerative braking force Fxfd, the larger the anti-dive force FAD. Further, the larger the front wheel working angle θfd, the larger the anti-dive force FAD.

なお、図４及び図５に示すように、前輪１１に摩擦制動力が付与される場合の前輪作用角θｆｂと、前輪１１に回生制動力が付与される場合の前輪作用角θｆｄとを比較した場合、前輪作用角θｆｄが前輪作用角θｆｂよりも小さくなる。これは、前輪回生制動力Ｆｘｆｄの前輪１１に対する作用点Ｐ３が、前輪摩擦制動力Ｆｘｆｂの前輪１１に対する作用点Ｐ２よりも車両上方に位置するためである。その結果、回生制動力が前輪１１に付与される場合に発生するアンチダイブ力ＦＡＤは、摩擦制動力が前輪１１に付与される場合に発生するアンチダイブ力ＦＡＤよりも小さくなる。

As shown in FIGS. 4 and 5, the front wheel working angle θfb when friction braking force is applied to the front wheels 11 and the front wheel working angle θfd when regenerative braking force is applied to the front wheels 11 are compared. In this case, the front wheel working angle θfd becomes smaller than the front wheel working angle θfb. This is because the point of action P3 of the front wheel regenerative braking force Fxfd on the front wheels 11 is located above the point of action P2 of the front wheel friction braking force Fxfb on the front wheels 11. As a result, the anti-dive force FAD generated when the regenerative braking force is applied to the front wheels 11 is smaller than the anti-dive force FAD generated when the friction braking force is applied to the front wheels 11.

Next, the magnitude relationship between the rear wheel friction braking force Fxrb and the antilift force FAL and the magnitude relationship between the rear wheel regenerative braking force Fxrd and the antilift force FAL will be described.
When the friction braking force is applied to the rear wheels 12, the point of action of the rear wheel friction braking force Fxrb on the rear wheels 12 is the ground contact point between the rear wheels 12 and the road surface 150. When the regenerative braking force is applied to the rear wheels 12, the point of action of the rear wheel regenerative braking force Fxrd on the rear wheels 12 is the center of rotation of the rear wheels 12. Therefore, the anti-lift force FAL generated when the regenerative braking force is applied to the rear wheels 12 is smaller than the anti-lift force FAL generated when the friction braking force is applied to the rear wheels 12.

Next, with reference to FIGS. 6 to 8, a processing routine executed by the control device 35 of the braking device 30 when applying the braking force to the vehicle 10 will be described. The processing routine shown in FIG. 6 is repeatedly executed when applying a braking force to the vehicle 10.

As shown in FIG. 6, in the first step S11 in this processing routine, the front-rear braking force distribution ratio n is derived by the distribution ratio deriving unit 353. For example, the front-rear braking force distribution ratio n is derived so that the front-rear braking force distribution ratio n does not fall below the ideal front-rear braking force distribution ratio. The ideal front-rear braking force distribution ratio is a front-rear braking force distribution ratio in which the front wheels 11 and the rear wheels 12 are locked at the same time. Subsequently, in the next step S12, the target pitch angle APTr and the required pitching moment MpR are derived by the target setting unit 352. The required pitching moment MpR is the pitching moment of the vehicle 10 required to set the pitch angle AP of the vehicle 10 as the target pitch angle APTr. For example, the target setting unit 352 derives the target pitch angle APTr so that the larger the required vehicle braking force FxR, the larger the value. Further, the target setting unit 352 derives a smaller value as the required pitching moment MpR as the target pitch angle APTr is larger.

Then, in step S13, both the friction regeneration distribution ratio nf of the front wheels 11 and the friction regeneration distribution ratio nr of the rear wheels 12 are derived by the distribution ratio derivation unit 353. The derivation process of the friction regeneration distribution ratios nf and nr will be described later with reference to FIG. When the friction regeneration distribution ratios nf and nr are derived, the process proceeds to the next step S14.

In step S14, the front wheel friction braking force required value FxfbR and the front wheel regenerative braking force required value are based on the front-rear braking force distribution ratio n and the friction regeneration distribution ratio nf, nr and the required vehicle braking force FxR by the operation instruction unit 354. FxfdR, rear wheel friction braking force required value FxrbR, and rear wheel regenerative braking force required value FxrdR are derived. For example, by using the following relational expressions (Equation 3), (Equation 4), (Equation 5) and (Equation 6), the front wheel friction braking force required value FxfbR, the front wheel regenerative braking force required value FxfdR, and the rear wheel friction control The required power value FxrbR and the required rear wheel regenerative braking force FxrdR can be calculated.

関係式（式３）及び（式４）によれば、前輪摩擦制動力要求値ＦｘｆｂＲ及び前輪回生制動力要求値ＦｘｆｄＲは、前後制動力配分比ｎが大きいほど大きくなる。前輪摩擦制動力要求値ＦｘｆｂＲは、前輪１１の摩擦回生配分比ｎｆが大きいほど大きくなる。前輪回生制動力要求値ＦｘｆｄＲは、前輪１１の摩擦回生配分比ｎｆが小さいほど大きくなる。関係式（式５）及び（式６）によれば、後輪摩擦制動力要求値ＦｘｒｂＲ及び後輪回生制動力要求値ＦｘｒｄＲは、前後制動力配分比ｎが小さいほど大きくなる。後輪摩擦制動力要求値ＦｘｒｂＲは、後輪１２の摩擦回生配分比ｎｒが大きいほど大きくなる。後輪回生制動力要求値ＦｘｒｄＲは、後輪１２の摩擦回生配分比ｎｒが小さいほど大きくなる。

According to the relational expressions (Equation 3) and (Equation 4), the front wheel friction braking force required value FxfbR and the front wheel regenerative braking force required value FxfdR become larger as the front-rear braking force distribution ratio n is larger. The front wheel friction braking force required value FxfbR increases as the friction regeneration distribution ratio nf of the front wheels 11 increases. The front wheel regenerative braking force required value FxfdR increases as the friction regeneration distribution ratio nf of the front wheels 11 decreases. According to the relational expressions (Equation 5) and (Equation 6), the rear wheel friction braking force required value FxrbR and the rear wheel regenerative braking force required value FxrdR become larger as the front-rear braking force distribution ratio n is smaller. The rear wheel friction braking force required value FxrbR increases as the friction regeneration distribution ratio nr of the rear wheels 12 increases. The rear wheel regenerative braking force required value FxrdR increases as the friction regeneration distribution ratio nr of the rear wheels 12 decreases.

When each braking force required value FxfbR, FxfdR, FxrbR, FxrdR is calculated, the process shifts to the next step S15. In step S15, regenerative braking is instructed by the operation instruction unit 354. That is, information regarding the front wheel regenerative braking force required value FxfdR and the rear wheel regenerative braking force required value FxrdR calculated by the operation instruction unit 354 is transmitted to the motor control device 52.

Then, the amount of power generated by the motor generator 51F is controlled by the front wheel regeneration control unit 62F of the motor control device 52. Further, the power generation amount of the motor generator 51R is controlled by the rear wheel regeneration control unit 62R.

Subsequently, in the next step S16, as a response to the transmission of information regarding the front wheel regenerative braking force required value FxfdR and the rear wheel regenerative braking force required value FxrdR, the actual front wheel regenerative braking force Fxfd and the rear wheel regeneration system are received from the motor control device 52. It is determined whether or not the information regarding the power Fxrd has been received. If the information has not yet been received (S16: NO), the determination in step S16 is repeated until the information is received. On the other hand, when the information is received (S16: YES), the process proceeds to the next step S17.

In step S17, the distribution ratio derivation unit 353 recalculates the front-rear braking force distribution ratio n, the friction regeneration distribution ratio nf of the front wheels 11, and the friction regeneration distribution ratio nr of the rear wheels 12. That is, the actual front wheel regenerative braking force Fxfd indicated by the information is different from the front wheel regenerative braking force required value FxfdR, and the actual rear wheel regenerative braking force Fxrd indicated by the information is the rear wheel regenerative braking force. If at least one of the differences from the required value FxrdR is satisfied, the front-rear braking force distribution ratio n and the friction regeneration distribution ratios nf and nr are recalculated, respectively. The recalculation process of the front-rear braking force distribution ratio n and the friction regeneration distribution ratios nf and nr will be described later.

Then, in the next step S18, the operation instruction unit 354 recalculates the front wheel friction braking force required value FxfbR and the rear wheel friction braking force required value FxrbR, respectively. That is, in the above relational expression (Equation 3), the recalculated front-rear braking force distribution ratio n is substituted into "n", and the recalculated friction regenerative distribution ratio nf of the front wheel 11 is substituted into "nf". As a result, the front wheel friction braking force required value FxfbR is recalculated. Similarly, in the above relational expression (Equation 5), the recalculated front-rear braking force distribution ratio n is substituted into "n", and the recalculated friction regenerative distribution ratio nr of the rear wheels 12 is substituted into "nr". By substituting, the rear wheel friction braking force required value FxrbR is recalculated.

That is, when at least one of the front wheel regenerative braking force required value FxfdR and the rear wheel regenerative braking force required value FxrdR cannot be realized, the front-rear braking force distribution is performed in order to suppress the deviation between the vehicle pitch angle AP and the target pitch angle APTr. The ratio n and the friction regeneration distribution ratios nf and nr are recalculated. Therefore, in the present embodiment, it can be said that the distribution ratio deriving unit 353 derives the front-rear braking force distribution ratio n and the friction regeneration distribution ratios nf and nr based on the target pitch angle APTr.

When the recalculation of the front wheel friction braking force required value FxfbR and the rear wheel friction braking force required value FxrbR is completed, the process shifts to the next step S19.
The actual front wheel regenerative braking force Fxfd may be equal to the front wheel regenerative braking force required value FxfdR, and the actual rear wheel regenerative braking force Fxrd may be equal to the rear wheel regenerative braking force required value FxrdR. In this case, the processes of steps S17 and S18 are skipped.

In step S19, friction braking is instructed by the operation instruction unit 354. That is, the friction control unit 355 is instructed to operate the braking actuator 33 based on the front wheel friction braking force required value FxfbR and the rear wheel friction braking force required value FxrbR calculated by the operation instruction unit 354.

Then, in the friction control unit 355, the WC pressure in the wheel cylinder 21 for the front wheels 11 becomes the hydraulic pressure corresponding to the front wheel friction braking force required value FxfbR, and the WC pressure in the wheel cylinder 21 for the rear wheels 12 becomes the rear. The operation of the braking actuator 33 is controlled so that the hydraulic pressure corresponds to the wheel friction braking force required value FxrbR. After that, this processing routine is temporarily terminated.

Next, with reference to FIG. 7, the derivation process of the friction regeneration distribution ratios nf and nr in step S13 will be described. Each process shown in FIG. 7 is executed by the distribution ratio derivation unit 353.
In this processing routine, in step S21, it is determined whether or not the vehicle 10 equipped with the braking device 30 is a vehicle capable of applying regenerative braking force to both the front wheels 11 and the rear wheels 12. When the vehicle 10 is a vehicle capable of applying regenerative braking force to both the front wheels 11 and the rear wheels 12 (S21: YES), the process proceeds to the next step S22. In step S22, it is determined whether or not the maximum value Jfmax of the front wheel coefficient is equal to or less than the maximum value Jrmax of the rear wheel coefficient. The maximum value Jfmax of the front wheel coefficient and the maximum value Jrmax of the rear wheel coefficient are values of "0" or more and "1" or less, respectively.

Here, the calculation process of the maximum value Jfmax of the front wheel coefficient and the maximum value Jrmax of the rear wheel coefficient will be described.
The pitching moment Mp of the vehicle 10 at the time of vehicle braking can be expressed by the following relational expression (Equation 7). In the relational expression (Equation 7), "H" is the height of the center of gravity of the vehicle 10, and "MpA" is the pitching moment generated in the vehicle 10 by the braking force distribution. That is, the pitching moment MpA can be changed by adjusting the front-rear braking force distribution ratio n, the friction regeneration distribution ratio nf of the front wheels 11, and the friction regeneration distribution ratio nr of the rear wheels 12. Therefore, the pitching moment MpA generated in the vehicle 10 by the braking force distribution is also referred to as "controllable pitching moment MpA". Then, the controllable pitching moment MpA can be expressed by the following relational expression (Equation 8).

関係式（式８）において、「Ｚｆｂ」は前輪１１への摩擦制動力の付与によって発生するアンチダイブ力であり、「Ｚｆｄ」は前輪１１への回生制動力の付与によって発生するアンチダイブ力である。また、「Ｚｒｂ」は後輪１２への摩擦制動力の付与によって発生するアンチリフト力であり、「Ｚｒｄ」は後輪１２への回生制動力の付与によって発生するアンチリフト力である。前輪１１への摩擦制動力の付与に対するアンチダイブ力の関係を示す係数ＫＺｆｂ、前輪１１への回生制動力の付与に対するアンチダイブ力の関係を示す係数ＫＺｆｄ、後輪１２への摩擦制動力の付与に対するアンチリフト力の関係を示す係数ＫＺｒｂ、及び、後輪１２への回生制動力の付与に対するアンチリフト力の関係を示す係数ＫＺｒｄは、以下の関係式（式９）〜（式１２）のように表すことができる。なお、関係式（式１１）及び（式１２）において、「Ｌｒ」は車両重心から後輪１２の車軸までの距離である後輪側距離のことである。また、「θｒｂ」は、後輪１２と路面１５０との接地点と後輪１２用のサスペンションの回転中心とを繋ぐ直線と、路面１５０とのなす角である。また、「θｒｄ」は、後輪１２の回転中心と後輪１２用のサスペンションの回転中心とを繋ぐ直線と、路面１５０とのなす角である。

In the relational expression (Equation 8), "Zfb" is an anti-dive force generated by applying a friction braking force to the front wheels 11, and "Zfd" is an anti-dive force generated by applying a regenerative braking force to the front wheels 11. is there. Further, "Zrb" is an anti-lift force generated by applying a friction braking force to the rear wheels 12, and "Zrd" is an anti-lift force generated by applying a regenerative braking force to the rear wheels 12. Coefficient KZfb indicating the relationship of anti-dive force to the application of friction braking force to the front wheels 11, coefficient KZfd indicating the relationship of anti-dive force to the application of regenerative braking force to the front wheels 11, and application of friction braking force to the rear wheels 12. The coefficient KZrb indicating the relationship of the anti-lift force with respect to and the coefficient KZrd indicating the relationship of the anti-lift force with respect to the application of the regenerative braking force to the rear wheel 12 are as shown in the following relational expressions (Equation 9) to (Equation 12). Can be expressed in. In the relational expressions (Equation 11) and (Equation 12), "Lr" is the distance on the rear wheel side, which is the distance from the center of gravity of the vehicle to the axle of the rear wheel 12. Further, "θrb" is an angle formed by the straight line connecting the ground contact point between the rear wheel 12 and the road surface 150 and the rotation center of the suspension for the rear wheel 12 and the road surface 150. Further, "θrd" is an angle formed by the straight line connecting the rotation center of the rear wheel 12 and the rotation center of the suspension for the rear wheel 12 and the road surface 150.

要求ピッチングモーメントＭｐＲは、上記各関係式（式３）〜（式６），（式８）〜（式１２）などに基づいて以下の関係式（式１３）のように表すことができる。

The required pitching moment MpR can be expressed as the following relational expression (Equation 13) based on the above relational expressions (Equation 3) to (Equation 6), (Equation 8) to (Equation 12) and the like.

関係式（式９）における「Ｌｆ・ｔａｎθｆｂ」を「Ｙａ」とし、関係式（式１０）における「Ｌｆ・ｔａｎθｆｄ」を「Ｙｂ」とする。また、関係式（式１１）における「Ｌｒ・ｔａｎθｒｂ」を「Ｙｃ」とし、関係式（式１２）における「Ｌｒ・ｔａｎθｒｄ」を「Ｙｄ」とする。この場合、関係式（式１３）を、関係式（式１４）及び（式１５）のように変形することができる。

Let "Lf · tan θfb" in the relational expression (Equation 9) be "Ya", and let "Lf · tan θfd" in the relational expression (Equation 10) be "Yb". Further, "Lr · tan θrb" in the relational expression (Equation 11) is referred to as "Yc", and "Lr · tan θrd" in the relational expression (Equation 12) is referred to as "Yd". In this case, the relational expression (Equation 13) can be modified as the relational expression (Equation 14) and (Equation 15).

前輪回生制動力Ｆｘｆｄと後輪回生制動力Ｆｘｒｄとの和を車両回生制動力Ｆｘｄとした場合、車両回生制動力Ｆｘｄは、以下の関係式（式１６）のように表すことができる。そして、前輪摩擦制動力Ｆｘｆｂと後輪摩擦制動力Ｆｘｒｂと前輪回生制動力Ｆｘｆｄと後輪回生制動力Ｆｘｒｄとの和を車両制動力Ｆｘとした場合、車両制動力Ｆｘのうち、車両回生制動力Ｆｘｄが占める割合のことを「係数Ｊ」とした場合、係数Ｊは以下の関係式（式１７）のように表すことができる。

When the sum of the front wheel regenerative braking force Fxfd and the rear wheel regenerative braking force Fxrd is the vehicle regenerative braking force Fxd, the vehicle regenerative braking force Fxd can be expressed as the following relational expression (Equation 16). When the sum of the front wheel friction braking force Fxfb, the rear wheel friction braking force Fxrb, the front wheel regenerative braking force Fxfd, and the rear wheel regenerative braking force Fxrd is the vehicle braking force Fx, the vehicle regenerative braking force of the vehicle braking force Fx When the ratio occupied by Fxd is defined as "coefficient J", the coefficient J can be expressed as the following relational expression (Equation 17).

車両制動力Ｆｘのうち、前輪回生制動力Ｆｘｆｄが占める割合のことを「前輪用係数Ｊｆ」とし、車両制動力Ｆｘのうち、後輪回生制動力Ｆｘｒｄが占める割合のことを「後輪用係数Ｊｒ」とする。この場合、上記関係式（式１４）、（式１５）及び（式１７）によれば、前輪用係数Ｊｆを以下の関係式（１８）のように表すことができる。また、後輪用係数Ｊｒを以下の関係式（１９）のように表すことができる。

The ratio of the front wheel regenerative braking force Fxfd to the vehicle braking force Fx is defined as the "front wheel coefficient Jf", and the ratio of the rear wheel regenerative braking force Fxrd to the vehicle braking force Fx is defined as the "rear wheel coefficient". Let's say "Jr". In this case, according to the above relational expressions (Equation 14), (Equation 15) and (Equation 17), the front wheel coefficient Jf can be expressed as the following relational expression (18). Further, the coefficient Jr for the rear wheels can be expressed as the following relational expression (19).

関係式（式１８）は、前輪１１の摩擦回生配分比ｎｆを変数とする一次関数である。関係式（式１９）は、後輪１２の摩擦回生配分比ｎｒを変数とする一次関数である。そのため、横軸を摩擦回生配分比ｎｆ，ｎｒとし、縦軸を係数Ｊｆ，Ｊｒとするグラフ上では、図８において、線Ｋｆは関係式（式１８）を表す線であり、線Ｋｒは関係式（式１９）を表す線である。摩擦回生配分比ｎｆ，ｎｒは「０」以上であって且つ「１」以下であり、係数Ｊｆ，Ｊｒもまた「０」以上であって且つ「１」以下である。そのため、図８に示す領域Ｗ内において、前輪用係数Ｊｆの最大値が前輪用係数の最大値Ｊｆｍａｘとして導出される。同様に、領域Ｗ内において、後輪用係数Ｊｒの最大値が後輪用係数の最大値Ｊｒｍａｘとして導出される。

The relational expression (Equation 18) is a linear function with the friction regeneration distribution ratio nf of the front wheels 11 as a variable. The relational expression (Equation 19) is a linear function with the friction regeneration distribution ratio nr of the rear wheels 12 as a variable. Therefore, on the graph in which the horizontal axis is the friction regeneration distribution ratio nf and nr and the vertical axis is the coefficients Jf and Jr, in FIG. 8, the line Kf is a line representing the relational expression (Equation 18), and the line Kr is a relational line. It is a line representing the formula (formula 19). The friction regeneration distribution ratios nf and nr are “0” or more and “1” or less, and the coefficients Jf and Jr are also “0” or more and “1” or less. Therefore, in the region W shown in FIG. 8, the maximum value of the front wheel coefficient Jf is derived as the maximum value Jfmax of the front wheel coefficient. Similarly, in the region W, the maximum value of the rear wheel coefficient Jr is derived as the maximum value Jrmax of the rear wheel coefficient.

Returning to FIG. 7, in step S22, when the maximum value Jfmax of the front wheel coefficient is equal to or less than the maximum value Jrmax of the rear wheel coefficient (YES), the process proceeds to the next step S23. In step S23, the friction regeneration distribution ratio nf of the front wheels 11 is calculated based on the above relational expression (Equation 18) and the maximum value Jfmax of the coefficient for the front wheels. That is, the friction regeneration distribution ratio nf can be calculated by substituting the maximum value Jfmax of the front wheel coefficient into "Jf" in the relational expression (Equation 18). Subsequently, in the next step S24, the friction regeneration distribution ratio nr of the rear wheels 12 is calculated based on the above relational expression (Equation 19). That is, in the relational expression (Equation 19), the friction regeneration distribution ratio nr is calculated by substituting a value equal to the maximum value Jfmax of the front wheel coefficient into “Jr”. When the friction regeneration distribution ratios nf and nr are calculated in this way, the processing routine is terminated.

On the other hand, in step S22, when the maximum value Jfmax of the front wheel coefficient is larger than the maximum value Jrmax of the rear wheel coefficient (NO), the process proceeds to the next step S25. In step S25, the friction regeneration distribution ratio nr of the rear wheels 12 is calculated based on the above relational expression (Equation 19) and the maximum value Jrmax of the coefficient for the rear wheels. That is, the friction regeneration distribution ratio nr can be calculated by substituting the maximum value Jrmax of the coefficient for the rear wheels into "Jr" in the relational expression (Equation 19). Subsequently, in the next step S26, the friction regeneration distribution ratio nf of the front wheels 11 is calculated based on the above relational expression (Equation 18). That is, in the relational expression (Equation 18), the friction regeneration distribution ratio nf is calculated by substituting a value equal to the maximum value Jrmax of the rear wheel coefficient into “Jf”. When the friction regeneration distribution ratios nf and nr are calculated in this way, the processing routine is terminated.

In the example shown in FIG. 8, the maximum value Jfmax of the front wheel coefficient is smaller than the maximum value Jrmax of the rear wheel coefficient. Therefore, the value when the front wheel coefficient Jf becomes equal to the maximum value Jfmax is calculated as the friction regeneration distribution ratio nf for the front wheels. In this case, the friction regeneration distribution ratio nf is “0”. That is, the front wheel regenerative braking force Fxfd is maximized. On the other hand, the value when the rear wheel coefficient Jr is equal to the maximum value Jfmax of the front wheel coefficient is calculated as the friction regeneration distribution ratio nr for the rear wheels. In this case, the friction regeneration distribution ratio nr is larger than "0" and less than "1".

On the contrary, the maximum value Jrmax of the rear wheel coefficient may be smaller than the maximum value Jfmax of the front wheel coefficient. In this case, the value when the coefficient Jr for the rear wheels becomes equal to the maximum value Jrmax is calculated as the friction regeneration distribution ratio nr for the rear wheels. As a result, the friction regeneration distribution ratio nr becomes "0" or "1". On the other hand, the value when the front wheel coefficient Jf is equal to the maximum value Jrmax of the rear wheel coefficient is calculated as the friction regeneration distribution ratio nf for the front wheels. In this case, the friction regeneration distribution ratio nf is larger than "0" and less than "1".

Returning to FIG. 7, in step S21, when the vehicle 10 equipped with the braking device 30 is not a vehicle capable of applying regenerative braking force to both the front wheels 11 and the rear wheels 12 (NO), the process proceeds to the next step S27. Will be migrated. In step S27, it is determined whether or not the vehicle 10 is a vehicle that can apply the regenerative braking force to the front wheels 11 but cannot apply the regenerative braking force to the rear wheels 12. That is, it is determined whether or not the regenerative braking device 50, which has the motor generator 51F but does not have the motor generator 51R, is adopted as the regenerative braking device 50. When the vehicle 10 is a vehicle that can apply the regenerative braking force to the front wheels 11 but cannot apply the regenerative braking force to the rear wheels 12 (S27: YES), the process shifts to the next step S28. ..

In step S28, “1” is set as the friction regeneration distribution ratio nr of the rear wheels 12. This is because the vehicle 10 cannot apply the regenerative braking force to the rear wheels 12. Subsequently, in the next step S29, the friction regeneration distribution ratio nf of the front wheels 11 is calculated. For example, the friction regeneration distribution ratio nf is calculated using the above relational expression (Equation 15). When the friction regeneration distribution ratios nf and nr are calculated in this way, the processing routine is terminated.

On the other hand, in step S27, when the vehicle 10 is not a vehicle that can apply the regenerative braking force to the front wheels 11 but cannot apply the regenerative braking force to the rear wheels 12 (NO), the vehicle 10 is the rear wheels. Since the vehicle can apply the regenerative braking force to the 12 but cannot apply the regenerative braking force to the front wheels 11, the process proceeds to the next step S30.

In step S30, "1" is set as the friction regeneration distribution ratio nf of the front wheels 11. This is because the vehicle 10 cannot apply the regenerative braking force to the front wheels 11. Subsequently, in the next step S31, the friction regeneration distribution ratio nr of the rear wheels 12 is calculated. For example, the friction regeneration distribution ratio nr is calculated using the above relational expression (Equation 14). When the friction regeneration distribution ratios nf and nr are calculated in this way, the processing routine is terminated.

Next, the recalculation processing of the front-rear braking force distribution ratio n and the friction regeneration distribution ratios nf and nr in step S18 will be described. The recalculation process is executed by the distribution ratio derivation unit 353.

When executing the recalculation process, the required pitching moment MpR, the required vehicle braking force FxR, the front wheel regenerative braking force Fxfd, and the rear wheel regenerative braking force Fxrd are known. Then, based on these, the front-rear braking force distribution ratio n and the friction regeneration distribution ratios nf and nr are recalculated.

For example, consider a case where the front wheel regenerative braking force Fxfd is less than the front wheel regenerative braking force required value FxfdR. When the front-rear braking force distribution ratio n is maintained under such a situation, the friction regeneration distribution ratio nf of the front wheels 11 becomes larger than that before the recalculation. Then, the anti-dive force FAD generated in the vehicle 10 becomes large. In order not to change the required pitching moment MpR even if the anti-dive force FAD becomes large in this way, it is necessary to reduce the anti-lift force FAL. In order to reduce the anti-lift force FAL while maintaining the rear wheel braking force Fxr, it is conceivable to reduce the friction regeneration distribution ratio nr of the rear wheels 12. By reducing the friction regeneration distribution ratio nr in this way, the rear wheel friction braking force Fxrb can be reduced, and as a result, the increase in the anti-dive force FAD can be offset by the decrease in the anti-lift force FAL.

However, when the friction regeneration distribution ratio nr of the rear wheels 12 is reduced in this way, the amount of decrease in the antilift force FAL may not be increased to the amount of increase in the antidive force FAD. In such a case, by changing the front-rear braking force distribution ratio n from the value before recalculation, it is possible to increase the amount of decrease in the anti-lift force FAL while suppressing the increase in the anti-dive force FAD. As a result, in calculation, the increase in anti-dive force FAD can be completely offset by the decrease in anti-lift force FAL.

Further, for example, consider a case where the rear wheel regenerative braking force Fxrd is less than the rear wheel regenerative braking force required value FxrdR. When the front-rear braking force distribution ratio n is maintained under such a situation, the friction regeneration distribution ratio nr of the rear wheels 12 becomes larger than that before the recalculation. Then, the anti-lift force FAL generated in the vehicle 10 becomes large. In order not to change the required pitching moment MpR even if the anti-lift force FAL becomes large in this way, it is necessary to reduce the anti-dive force FAD. In order to reduce the anti-dive force FAD while maintaining the front wheel braking force Fxf, it is conceivable to reduce the friction regeneration distribution ratio nf of the front wheels 11. By reducing the friction regeneration distribution ratio nf in this way, the front wheel friction braking force Fxfb can be reduced, and as a result, the increase in the antilift force FAL can be offset by the decrease in the antidive force FAD.

However, when the friction regeneration distribution ratio nf of the front wheels 11 is reduced in this way, the amount of decrease in the anti-dive force FAD may not be as large as the amount of increase in the anti-lift force FAL. In such a case, the front-rear braking force distribution ratio n can also be changed from the value before recalculation, so that the amount of decrease in the anti-dive force FAD can be increased while suppressing the increase in the anti-lift force FAL. As a result, in calculation, the increase in anti-lift force FAL can be completely offset by the decrease in anti-dive force FAD.

The operation and effect of this embodiment will be described.
When the vehicle is braking, the front-rear braking force distribution ratio n and the friction regeneration distribution ratio nf, nr of the wheels to which the regenerative braking force can be applied are adjusted so that the pitch angle AP of the vehicle 10 approaches the target pitch angle APTr. .. That is, the required pitching moment MpR is set to a value corresponding to the target pitch angle APTr. Further, the front-rear braking force distribution ratio n is tentatively derived.

Then, based on the required pitching moment MpR and the front-rear braking force distribution ratio n, the friction regeneration distribution ratio nf of the front wheels 11 and the friction regeneration distribution ratio nr of the rear wheels 12 are calculated. As described above, when the regenerative braking force is applied to the front wheels 11, the anti-dive force FAD is less likely to increase as compared with the case where the friction braking force is applied to the front wheels 11. Therefore, the larger the target pitch angle APTr, that is, the smaller the required pitching moment MpR, the smaller the friction regeneration distribution ratio nf of the front wheels 11 tends to be. As a result, the front wheel regenerative braking force Fxfd can be increased, and the anti-dive force FAD of the vehicle 10 is less likely to be increased. As a result, the pitch angle AP of the vehicle 10 can be increased.

Further, as described above, when the regenerative braking force is applied to the rear wheels 12, the anti-lift force FAL is less likely to increase as compared with the case where the friction braking force is applied to the rear wheels 12. Therefore, the larger the target pitch angle APTr, that is, the smaller the required pitching moment MpR, the smaller the friction regeneration distribution ratio nf of the rear wheels 12 tends to be. As a result, the rear wheel regenerative braking force Fxrd can be increased, and as a result, the anti-lift force FAL of the vehicle 10 is less likely to increase. As a result, the pitch angle AP of the vehicle 10 can be increased.

Therefore, in the present embodiment, the pitching posture of the vehicle 10 can be controlled. Therefore, even when the front-rear braking force distribution ratio n is changed while changing the magnitude of the regenerative braking force of the vehicle 10 as a whole, it is possible to suppress the change in the pitching posture of the vehicle 10 due to such a change.

By the way, the front wheel regenerative braking force required value FxfdR and the rear wheel regenerative braking force required value FxrdR are calculated based on the friction regeneration distribution ratios nf and nr calculated as described above, and the front wheel regenerative braking force required value FxfdR and the rear wheel regenerative system are calculated. Even if the information regarding the power required value FxrdR is transmitted to the regenerative braking device 50, the actual front wheel regenerative braking force Fxfd may be lower than the front wheel regenerative braking force required value FxfdR. Further, the actual rear wheel regenerative braking force Fxrd may be less than the rear wheel regenerative braking force required value FxrdR.

Therefore, in the present embodiment, the request is made even when the actual front wheel regenerative braking force Fxfd is lower than the front wheel regenerative braking force required value FxfdR or the actual rear wheel regenerative braking force Fxrd is lower than the rear wheel regenerative braking force required value FxrdR. The front-rear braking force distribution ratio n and the friction regeneration distribution ratios nf and nr are recalculated so that the pitching moment MpR can be generated in the vehicle 10. Then, based on the recalculated distribution ratios n, nf, nr, the actual front wheel regenerative braking force Fxfd, and the actual rear wheel regenerative braking force Fxrd, the front wheel friction braking force required value FxfbR and the rear wheel friction braking force required. The value FxrbR is recalculated. Then, by operating the braking actuator 33 based on the recalculated front wheel friction braking force required value FxfbR and the rear wheel friction braking force required value FxrbR, the pitch angle AP of the vehicle 10 is satisfied while satisfying the required braking force for the vehicle 10. The deviation from the target pitch angle APTr can be suppressed. That is, the controllability of the pitching posture of the vehicle 10 can be improved.

In the present embodiment, when calculating the friction regeneration distribution ratios nf and nr, the friction regeneration distribution ratios nf and nr are calculated so as to maximize the regenerative braking force applied to the wheel to be regenerated. When calculating the friction regeneration distribution ratio nf of the front wheels 11, the larger the front wheel coefficient Jf, the larger the friction regeneration distribution ratio nr of the rear wheels 12. That is, in the example shown in FIG. 8, the value when the front wheel coefficient Jf reaches the maximum value Jfmax is calculated as the friction regeneration distribution ratio nf. Then, based on this friction regeneration distribution ratio nf, the friction regeneration distribution ratio nr of the rear wheels 12 is calculated. As a result, the rear wheel regenerative braking force Fxrd can be increased as much as possible.

On the contrary, when calculating the friction regeneration distribution ratio nr of the rear wheels 12, the larger the coefficient Jr for the rear wheels, the larger the friction regeneration distribution ratio nf of the front wheels 11. That is, the value when the rear wheel coefficient Jr becomes the maximum value Jrmax is calculated as the friction regeneration distribution ratio nr. Then, based on this friction regeneration distribution ratio nr, the friction regeneration distribution ratio nf of the front wheels 11 is calculated. As a result, the front wheel regenerative braking force Fxfd can be increased as much as possible.

(Second Embodiment)
Next, a second embodiment of the vehicle braking device will be described with reference to FIGS. 9 to 11. In the present embodiment, the configuration of the hydraulic pressure generator and the contents of the setting process of the target pitch angle APTr and the required pitching moment MpR are different from those of the first embodiment. In the following description, the parts that are different from the first embodiment will be mainly described, and the same or corresponding member configurations as those in the first embodiment will be designated by the same reference numerals and duplicate description will be omitted. To do.

As shown in FIG. 9, the hydraulic pressure generating device 32 of the friction braking device 31 assists the input from the reservoir tank 81 for storing the brake fluid, the master cylinder 82, and the braking operation member 321 to the master cylinder. It is provided with an assisting device 90 that outputs to 82.

The assisting device 90 applied to the braking device 30 of the present embodiment is configured so that the relationship between the operation amount SBP of the braking operation member 321 and the output from the assisting device 90 to the master cylinder 82 can be changed. Examples of such an assisting device 90 include a booster device disclosed in "Japanese Unexamined Patent Publication No. 2018-176853".

That is, as shown in FIG. 9, the assisting device 90 has an input unit 91 to which the braking operation member 321 is connected and an output unit 92 that presses the piston 821 of the master cylinder 82. The input unit 91 is displaced in the axial direction D1 in response to the operation of the braking operation member 321. The output unit 92 is arranged between the input unit 91 and the master cylinder 82 in the axial direction D1.

Further, the assisting device 90 includes a first electric motor 93, a second electric motor 94, and an operating mechanism 95. The operating mechanism 95 includes a first transmission mechanism 951 that transmits the output of the first electric motor 93 to the input unit 91, a second transmission mechanism 952 that transmits the output of the second electric motor 94 to the output unit 92, and an input unit 91. It has a third transmission mechanism 953 that outputs the output of the above to the output unit 92. According to this configuration, by changing the driving mode of each of the electric motors 93 and 94 during the braking operation of the driver, the operation amount SBP of the braking operation member 321 and the output from the assisting device 90 to the master cylinder 82 can be obtained. The relationship can be varied.

When the output from the assisting device 90 to the master cylinder 82 changes, the MC pressure, which is the hydraulic pressure generated in the master cylinder 82, changes. When the MC pressure changes in this way, the WC pressure in each wheel cylinder 21 communicating with the master cylinder 82 through the braking actuator 33 changes. When the WC pressure changes, the friction braking forces Fxfb and Fxrb applied to the wheels 11 and 12 change. That is, changing the relationship between the operation amount SBP of the braking operation member 321 and the output from the assisting device 90 to the master cylinder 82 is the relationship between the operation amount SBP of the braking operation member 321 and the vehicle braking force Fx. It is the same as changing the first relationship. Therefore, in the present embodiment, the assisting device 90 corresponds to the "braking relationship adjusting unit" that changes the first relationship.

The vehicle 10 provided with the braking device 30 of the present embodiment is provided with an operation unit 121 operated by the driver to select a traveling mode of the vehicle 10. The driving modes that can be selected include, for example, the sporty mode, which is a mode suitable for driving in which the vehicle 10 is repeatedly accelerated and decelerated more than when the normal mode is selected, and the vehicle 10 is added more than when the normal mode is selected. A luxury mode is available, which is a mode that suppresses deceleration. Then, the information regarding the selected traveling mode is input to the control device 35.

The control device 35 further has a relationship setting unit 356 that controls the assisting device 90 as a functional unit. The relationship setting unit 356 sets the first relationship based on the traveling mode selected through the operation of the operation unit 121. Then, the relationship setting unit 356 controls each of the electric motors 93 and 94 so as to satisfy the set first relationship when the driver is performing the braking operation.

In addition to the manipulated variable detection sensor 101 and the vehicle speed sensor 102, detection signals from the operating force detection sensor 103 are input to the control device 35. The operating force detection sensor 103 detects the operating force PBP input from the driver to the braking operation member 321 and outputs a signal corresponding to the operating force PBP as a detection signal. In the control device 35 capable of acquiring both the operating amount SBP and the operating force PBP in this way, the required vehicle braking force FxR is derived by the required braking force deriving unit 351 based on at least one of the operating amount SBP and the operating force PBP. Will be done.

In FIG. 10, the first reference relation CR10, which is the reference of the first relation, is shown by a solid line, and the first sudden braking relation CR11 and the first slow braking relation CR12 are shown by broken lines, respectively. The first reference relationship CR10 is the first relationship when the normal mode is selected as the traveling mode. The first sudden braking relationship CR11 is the first relationship when the sporty mode is selected as the traveling mode. The first slow braking relationship CR12 is the first relationship when the luxury mode is selected as the traveling mode.

As shown by a solid line in FIG. 10, the first reference relationship CR10 is a relationship in which the amount of change in the vehicle braking force Fx with respect to the change in the operation amount SBP increases as the operation amount SBP increases. As shown by the broken line in FIG. 10, the first sudden braking relation CR11 has a vehicle braking force Fx even if the operation amount SBP is the same, as compared with the case where the first reference relation CR10 is set as the first relation. This is the first relationship that can be increased. As shown by the broken line in FIG. 10, the first slow braking relation CR12 has a vehicle braking force Fx even if the operation amount SBP is the same, as compared with the case where the first reference relation CR10 is set as the first relation. This is the first relationship that can be made smaller.

Next, with reference to FIG. 11, the step S12 executed by the target setting unit 352 will be described. Step S12 is a process of deriving the required pitching moment MpR and the target pitch angle APTr.

When the front-rear braking force distribution ratio n is derived by the distribution ratio deriving unit 353 in step S11, the process shifts to the next step S12. In step S12, in the first step S121, the required pitching moment reference value MpB is derived. For example, the required pitching moment reference value MpB is equal to the required pitching moment MpR derived in step S12 in the first embodiment. Subsequently, in the next step S122, the pitching moment correction value Mpa is derived. The derivation process of the pitching moment correction value Mpa will be described later. Then, in the next step S123, a value obtained by subtracting the pitching moment correction value Mpa from the required pitching moment reference value MpB is calculated as the required pitching moment MpR. Subsequently, in step S124, the smaller the required pitching moment MpR, the larger the value is calculated as the target pitch angle APTr. When the target pitch angle APTr is calculated, the process of step S12 is completed, and the process shifts to the step S13.

Next, the specific processing contents of step S122 will be described with reference to FIGS. 10 and 12. The process described here is executed by the target setting unit 352.
In step S122, the required vehicle braking force FxR is acquired, and the operation amount SBP of the braking operation member 321 is acquired. Then, under the assumption that the first reference relation CR10 is set as the first relation, the operation amount SBP for realizing the required vehicle braking force FxR is derived as the reference operation amount SBPB as shown in FIG.

Subsequently, the value obtained by subtracting the reference manipulated variable SBPB from the current manipulated variable SBP is calculated as the manipulated variable ΔSBP. For example, when the first reference relation CR10 is set as the first relation, the manipulated variable SBP at the present time is equal to the reference variable SBPB, so the manipulated variable ΔSBP is “0”. When the first sudden braking relation CR11 is set as the first relation, the manipulated variable SBP at the present time is smaller than the reference manipulated variable SBPB, so that the manipulated variable ΔSBP has a negative value. When the first slow braking relation CR12 is set as the first relation, the manipulated variable SBP at the present time is larger than the reference manipulated variable SBPB, so that the manipulated variable ΔSBP is a positive value.

Then, the first correction value Mpa1 is derived based on the calculated manipulated variable ΔSBP. That is, when the manipulated variable ΔSBP is large, a value larger than when the manipulated variable ΔSBP is small is derived as the first correction value Mpa1. When the first correction value Mpa1 is derived in this way, the larger the first correction value Mpa1, the larger the value is derived as the pitching moment correction value Mpa. In the present embodiment, the first correction value Mpa1 is set as the pitching moment correction value Mpa.

According to step S12, the larger the pitching moment correction value Mpa, the smaller the required pitching moment MpR. The smaller the required pitching moment MpR, the larger the target pitch angle APTr. Therefore, when the manipulated variable ΔSBP is a positive value because the first relation is the first slow braking relation CR12, the manipulated variable ΔSBP is “0” because the first relation is the first reference relation CR10. The target pitch angle APTr becomes larger than in the case of. On the other hand, when the manipulated variable ΔSBP is a negative value because the first relationship is the first sudden braking relationship CR11, the manipulated variable ΔSBP is “0” because the first relationship is the first reference relationship CR10. The target pitch angle APTr becomes smaller than in the case of.

In FIG. 12, an example of a map for deriving the first correction value Mpa1 based on the manipulated variable difference ΔSBP is shown by a solid line. In the map MAP 11 shown by the solid line in FIG. 12, the larger the manipulated variable ΔSBP is, the larger the value is derived as the first correction value Mpa1. That is, when the manipulated variable ΔSBP is “0”, “0” is derived as the first correction value Mpa1. When the manipulated variable ΔSBP is a positive value, a positive value is derived as the first correction value Mpa1. Specifically, the larger the manipulated variable ΔSBP, the larger the first correction value Mpa1. On the other hand, when the manipulated variable ΔSBP is a negative value, a negative value is derived as the first correction value Mpa1. Specifically, the larger the absolute value of the manipulated variable ΔSBP, the larger the absolute value of the first correction value Mpa1.

According to this embodiment, in addition to the effects described in the first embodiment, the following effects can be further obtained.
In the vehicle 10 provided with the braking device 30, the larger the vehicle braking force Fx, the larger the target pitch angle APTr. Therefore, when the first slow braking relationship CR12 is set as the first relationship, it is difficult to increase the vehicle braking force Fx, so that the vehicle 10 does not easily pitch to the nose dive side during vehicle braking. That is, the pitching posture of the vehicle 10 is unlikely to change.

Here, when the pitching posture of the vehicle 10 changes at an early stage in response to its own braking operation, the driver may determine that the vehicle 10 is a vehicle having a good response to the braking operation. In other words, if the pitching posture of the vehicle 10 does not change easily in response to its own braking operation, the driver may determine that the vehicle 10 is a vehicle that does not respond well to the braking operation.

In this respect, in the present embodiment, when the first slow braking relation CR12 is set as the first relation, the required pitching moment MpR is compared with the case where the first reference relation CR10 is set as the first relation. Is suppressed. As a result, when the first slow braking relation CR12 is set as the first relation, even if the vehicle braking force Fx is the same, it is compared with the case where the first reference relation CR10 is set as the first relation. The target pitch angle APTr can be increased. That is, when the first slow braking relationship CR12 is set as the first relationship, the pitching posture of the vehicle 10 can be changed at an early stage. Therefore, when the first slow braking relationship CR12 is set as the first relationship, it is possible to prevent the driver from determining that the vehicle 10 is a vehicle that does not respond well to the braking operation.

On the other hand, in the present embodiment, when the first sudden braking relation CR11 is set as the first relation, the required pitching moment MpR is compared with the case where the first reference relation CR10 is set as the first relation. Growth is encouraged. As a result, when the first sudden braking relation CR11 is set as the first relation, even if the vehicle braking force Fx is the same, it is compared with the case where the first reference relation CR10 is set as the first relation. Therefore, the increase in the target pitch angle APTr is suppressed. That is, when the first sudden braking relationship CR11 is set as the first relationship, it is possible to prevent the pitch angle AP of the vehicle 10 from becoming too large or the pitch angle AP changing speed becoming too high.

(Third Embodiment)
Next, a third embodiment of the vehicle braking device will be described with reference to FIG. In the present embodiment, the content of the process of correcting the required pitching moment MpR based on the set first relationship is different from that of the second embodiment. In the following description, the parts that are different from each of the above embodiments will be mainly described, and the same or corresponding member configurations as those of each of the above embodiments will be designated by the same reference numerals and duplicate description will be omitted. To do.

Even in the assisting device 90 applied to the braking device 30 of the present embodiment, the first relationship can be changed as in the case of the second embodiment.
Next, in step S122, the process of deriving the pitching moment correction value Mpa and the first correction value Mpa1 will be described. In this embodiment, step S122 is executed by the target setting unit 352.

In step S122, the required vehicle braking force FxR and the reference operation amount SBPB are derived. Subsequently, the value obtained by subtracting the reference manipulated variable SBPB from the current manipulated variable SBP is calculated as the manipulated variable ΔSBP. Then, the first correction value Mpa1 is derived based on the calculated manipulated variable ΔSBP. In the present embodiment, when the manipulated variable ΔSBP is small, a value larger than when the manipulated variable ΔSBP is large is derived as the first correction value Mpa1. Then, the larger the first correction value Mpa1, the larger the value is derived as the pitching moment correction value Mpa. In the present embodiment, the first correction value Mpa1 is set as the pitching moment correction value Mpa.

In FIG. 12, an example of a map for deriving the first correction value Mpa1 based on the manipulated variable difference ΔSBP is shown by a broken line. In the map MAP 12 shown by the broken line in FIG. 12, the smaller the manipulated variable ΔSBP, the larger the value is derived as the first correction value Mpa1. That is, when the manipulated variable ΔSBP is “0”, “0” is derived as the first correction value Mpa1. When the manipulated variable ΔSBP is a negative value, a positive value is derived as the first correction value Mpa1. Specifically, the larger the absolute value of the manipulated variable ΔSBP, the larger the first correction value Mpa1. On the other hand, when the manipulated variable ΔSBP is a positive value, a negative value is derived as the first correction value Mpa1. Specifically, the larger the manipulated variable ΔSBP, the larger the absolute value of the first correction value Mpa1.

According to this embodiment, in addition to the effects described in the first embodiment, the following effects can be further obtained.
When the first sudden braking relation CR11 is set as the first relation, the required pitching moment MpR is less likely to increase as compared with the case where the first reference relation CR10 is set as the first relation. As a result, when the first sudden braking relation CR11 is set as the first relation, even if the vehicle braking force Fx is the same, it is compared with the case where the first reference relation CR10 is set as the first relation. The target pitch angle APTr can be increased. That is, when the first sudden braking relation CR11 is set as the first relation, the pitch angle AP of the vehicle 10 can be increased at an early stage. As a result, it is possible to increase the pitch angle AP of the vehicle 10 to some extent at the initial stage of vehicle braking, and then decelerate the vehicle 10 while maintaining a state in which the pitch angle AP is large.

On the other hand, when the first slow braking relation CR12 is set as the first relation, the increase of the required pitching moment MpR is promoted as compared with the case where the first reference relation CR10 is set as the first relation. .. As a result, when the first slow braking relation CR12 is set as the first relation, even if the vehicle braking force Fx is the same, it is compared with the case where the first reference relation CR10 is set as the first relation. Therefore, the increase in the target pitch angle APTr is suppressed. That is, when the first slow braking relationship CR12 is set as the first relationship, it is possible to suppress a change in the pitching posture of the vehicle 10 during vehicle braking.

(Fourth Embodiment)
Next, a fourth embodiment of the vehicle braking device will be described with reference to FIGS. 13 to 14. In the present embodiment, the contents of the setting process of the target pitch angle APTr and the required pitching moment MpR are different from those in the second embodiment. In the following description, the parts that are different from each of the above embodiments will be mainly described, and the same or corresponding member configurations as those of each of the above embodiments will be designated by the same reference numerals and duplicate description will be omitted. To do.

The assisting device 90 of the braking device 30 of the present embodiment has an operating force PBP input to the braking operation member 321 and an assisting device by changing the driving mode of each of the electric motors 93 and 94 during the braking operation of the driver. The relationship with the output from 90 to the master cylinder 82 can be varied. When the output from the assisting device 90 to the master cylinder 82 changes, the MC pressure of the master cylinder 82 changes. When the MC pressure changes in this way, the WC pressure in each wheel cylinder 21 changes, so that the friction braking forces Fxfb and Fxrb applied to the wheels 11 and 12 change. That is, changing the relationship between the operating force PBP input to the braking operating member 321 and the output from the assisting device 90 to the master cylinder 82 is the relationship between the operating force PBP and the vehicle braking force Fx. It's the same as changing the relationship. Therefore, in the present embodiment, the assisting device 90 corresponds to the "braking relationship adjusting unit" that changes the second relationship.

The relationship setting unit 356 of the control device 35 sets the second relationship based on the traveling mode selected through the operation of the operation unit 121. Then, the relationship setting unit 356 controls each of the electric motors 93 and 94 so as to satisfy the set second relationship when the driver is performing the braking operation.

In FIG. 13, the second reference relation CR20, which is the reference of the second relation, is shown by a solid line, and the second sudden braking relation CR21 and the second slow braking relation CR22 are shown by broken lines, respectively. The second reference relationship CR20 is a second relationship when the normal mode is selected as the traveling mode. The second sudden braking relationship CR21 is a second relationship when the sporty mode is selected as the traveling mode. The second slow braking relationship CR22 is a second relationship when the luxury mode is selected as the traveling mode.

As shown by a solid line in FIG. 13, the second reference relationship CR20 is a relationship in which the amount of change in the vehicle braking force Fx with respect to the change in the operating force PBP increases as the operating force PBP increases. As shown by the broken line in FIG. 13, the second sudden braking relation CR21 has a vehicle braking force Fx even if the operating force PBP is the same, as compared with the case where the second reference relation CR20 is set as the second relation. This is the second relationship that can be increased. As shown by the broken line in FIG. 13, the second slow braking relation CR22 has a vehicle braking force Fx even if the operating force PBP is the same, as compared with the case where the second reference relation CR20 is set as the second relation. This is the second relationship that can be made smaller.

Next, the above step S12 for deriving the required pitching moment MpR will be described. In this embodiment, step S12 is executed by the target setting unit 352.
In step S12, in the first step S121, the required pitching moment reference value MpB is derived as in the second embodiment. Subsequently, in the next step S122, the pitching moment correction value Mpa is derived. In the next step S123, a value obtained by subtracting the pitching moment correction value Mpa from the required pitching moment reference value MpB is calculated as the required pitching moment MpR. Then, the process of step S12 is completed, and the process shifts to the step S13.

Next, with reference to FIGS. 13 and 14, the specific processing contents of the above step S122 will be described.
In step S122, the required vehicle braking force FxR is acquired, and the operating force PBP input to the braking operating member 321 is acquired. Then, under the assumption that the second reference relation CR20 is set as the second relation, the operating force PBP for realizing the required vehicle braking force FxR is derived as the reference operating force PBPB as shown in FIG.

Subsequently, the value obtained by subtracting the reference operating force PBPB from the current operating force PBP is calculated as the operating force difference ΔPBP. For example, when the second reference relation CR20 is set as the second relation, the operating force difference ΔPBP is “0” because the current operating force PBP is equal to the reference operating force PBPB. When the second sudden braking relationship CR21 is set as the second relationship, the operating force difference ΔPBP is a negative value because the current operating force PBP is smaller than the reference operating force PBPB. When the second slow braking relationship CR22 is set as the second relationship, the operating force difference ΔPBP is a positive value because the current operating force PBP is larger than the reference operating force PBPB.

Then, the second correction value Mpa2 is derived based on the calculated operating force difference ΔPBP. That is, when the operating force difference ΔPBP is large, a value larger than when the operating force difference ΔPBP is small is derived as the second correction value Mpa2. When the second correction value Mpa2 is derived in this way, the larger the second correction value Mpa2 is, the larger the value is derived as the pitching moment correction value Mpa. In the present embodiment, the second correction value Mpa2 is set as the pitching moment correction value Mpa.

According to step S12, the larger the pitching moment correction value Mpa, the smaller the required pitching moment MpR. Further, the smaller the required pitching moment MpR, the larger the target pitch angle APTr. Therefore, when the operating force difference ΔPBP is a positive value because the second relationship is the second slow braking relationship CR22, the operating force difference ΔPBP is “0” because the second relationship is the second reference relationship CR20. The target pitch angle APTr becomes larger than in the case of. On the other hand, when the operating force difference ΔPBP is a negative value because the second relationship is the second sudden braking relationship CR21, the operating force difference ΔPBP is “0” because the second relationship is the second reference relationship CR20. The target pitch angle APTr becomes smaller than in the case of.

In FIG. 14, an example of a map for deriving the second correction value Mpa2 based on the operating force difference ΔPBP is shown by a solid line. In the map MAP 21 shown by the solid line in FIG. 14, the larger the operating force difference ΔPBP is, the larger the value is derived as the second correction value Mpa2. That is, when the operating force difference ΔPBP is “0”, “0” is derived as the second correction value Mpa2. When the operating force difference ΔPBP is a positive value, a positive value is derived as the second correction value Mpa2. Specifically, the larger the operating force difference ΔPBP, the larger the second correction value Mpa2. On the other hand, when the operating force difference ΔPBP is a negative value, a negative value is derived as the second correction value Mpa2. Specifically, the larger the absolute value of the operating force difference ΔPBP, the larger the absolute value of the second correction value Mpa2.

According to this embodiment, in addition to the effects described in the first embodiment, the following effects can be further obtained.
In the vehicle 10 provided with the braking device 30, the larger the vehicle braking force Fx, the larger the target pitch angle APTr. Therefore, when the second slow braking relationship CR22 is set as the second relationship, it is difficult to increase the vehicle braking force Fx, so that it is difficult for the vehicle 10 to make a pitching motion toward the nose dive side during vehicle braking. That is, the pitching posture of the vehicle 10 is unlikely to change.

In the present embodiment, when the second slow braking relation CR22 is set as the second relation, the required pitching moment MpR is increased as compared with the case where the second reference relation CR20 is set as the second relation. It is suppressed. As a result, when the second slow braking relationship CR22 is set as the second relationship, even if the vehicle braking force Fx is the same, it is compared with the case where the second reference relationship CR20 is set as the second relationship. The target pitch angle APTr can be increased. That is, when the second slow braking relationship CR22 is set as the second relationship, the pitching posture of the vehicle 10 can be changed at an early stage. Therefore, when the second slow braking relationship CR22 is set as the second relationship, it is possible to prevent the driver from determining that the vehicle 10 is a vehicle that does not respond well to the braking operation.

On the other hand, in the present embodiment, when the second sudden braking relation CR21 is set as the second relation, the required pitching moment MpR is compared with the case where the second reference relation CR20 is set as the second relation. Growth is encouraged. As a result, when the second sudden braking relation CR21 is set as the second relation, even if the vehicle braking force Fx is the same, it is compared with the case where the second reference relation CR20 is set as the second relation. Therefore, the increase in the target pitch angle APTr is suppressed. That is, when the second sudden braking relationship CR21 is set as the second relationship, it is possible to prevent the pitch angle AP of the vehicle 10 from becoming too large or the pitch angle AP changing speed becoming too high.

(Fifth Embodiment)
Next, a fifth embodiment of the vehicle braking device will be described with reference to FIG. In the present embodiment, the content of the process of correcting the required pitching moment MpR based on the set second relationship is different from that of the fourth embodiment. In the following description, the parts that are different from each of the above embodiments will be mainly described, and the same or corresponding member configurations as those of each of the above embodiments will be designated by the same reference numerals and duplicate description will be omitted. To do.

Even in the assisting device 90 applied to the braking device 30 of the present embodiment, the second relationship can be changed as in the case of the fourth embodiment.
Next, in step S122, the process of deriving the pitching moment correction value Mpa and the second correction value Mpa2 will be described. In this embodiment, step S122 is executed by the target setting unit 352.

In step S122, the required vehicle braking force FxR and the reference operating force PBPB are derived. Subsequently, the value obtained by subtracting the reference operating force PBPB from the current operating force PBP is calculated as the operating force difference ΔPBP. Then, the second correction value Mpa2 is derived based on the calculated operating force difference ΔPBP. In the present embodiment, when the operating force difference ΔPBP is small, a value larger than when the operating force difference ΔPBP is large is derived as the second correction value Mpa2. Then, the larger the second correction value Mpa2 is, the larger the value is derived as the pitching moment correction value Mpa. In the present embodiment, the second correction value Mpa2 is set as the pitching moment correction value Mpa.

In FIG. 14, an example of a map for deriving the second correction value Mpa2 based on the operating force difference ΔPBP is shown by a broken line. In the map MAP 22 shown by the broken line in FIG. 14, the smaller the operating force difference ΔPBP, the larger the value is derived as the second correction value Mpa2. That is, when the operating force difference ΔPBP is “0”, “0” is derived as the second correction value Mpa2. When the operating force difference ΔPBP is a negative value, a positive value is derived as the second correction value Mpa2. Specifically, the larger the absolute value of the operating force difference ΔPBP, the larger the second correction value Mpa2. On the other hand, when the operating force difference ΔPBP is a positive value, a negative value is derived as the second correction value Mpa2. Specifically, the larger the operating force difference ΔPBP, the larger the absolute value of the second correction value Mpa2.

According to this embodiment, in addition to the effects described in the first embodiment, the following effects can be further obtained.
When the second sudden braking relation CR21 is set as the second relation, the required pitching moment MpR is less likely to increase as compared with the case where the second reference relation CR20 is set as the second relation. As a result, when the second sudden braking relation CR21 is set as the second relation, even if the vehicle braking force Fx is the same, it is compared with the case where the second reference relation CR20 is set as the second relation. The target pitch angle APTr can be increased. That is, when the second sudden braking relationship CR21 is set as the second relationship, the pitch angle AP of the vehicle 10 can be increased at an early stage. As a result, it is possible to increase the pitch angle AP of the vehicle 10 to some extent at the initial stage of vehicle braking, and then decelerate the vehicle 10 while maintaining a state in which the pitch angle AP is large.

On the other hand, when the second slow braking relation CR22 is set as the second relation, the increase in the required pitching moment MpR is promoted as compared with the case where the second reference relation CR20 is set as the second relation. .. As a result, when the second slow braking relationship CR22 is set as the second relationship, even if the vehicle braking force Fx is the same, it is compared with the case where the second reference relationship CR20 is set as the second relationship. Therefore, the increase in the target pitch angle APTr is suppressed. That is, when the second slow braking relationship CR22 is set as the second relationship, it is possible to suppress the change in the pitching posture of the vehicle 10 during vehicle braking.

(Sixth Embodiment)
Next, a sixth embodiment of the vehicle braking device will be described with reference to FIGS. 15 and 16. In the present embodiment, the contents of the setting process of the target pitch angle APTr and the required pitching moment MpR are different from those in the second embodiment. In the following description, the parts that are different from each of the above embodiments will be mainly described, and the same or corresponding member configurations as those of each of the above embodiments will be designated by the same reference numerals and duplicate description will be omitted. To do.

The assisting device 90 of the braking device 30 of the present embodiment can be applied to the operation amount SBP of the braking operation member 321 and the braking operation member 321 by changing the driving mode of each of the electric motors 93 and 94 during the braking operation of the driver. The third relationship, which is the relationship with the input operating force PBP, can be changed. In the case of a configuration in which the required vehicle braking force FxR is derived based on the operating amount SBP and the operating force PBP, when the third relationship changes, the output from the assisting device 90 to the master cylinder 82 changes, and as a result, the master cylinder 82 MC pressure changes. When the MC pressure changes in this way, the WC pressure in each wheel cylinder 21 changes, so that the friction braking forces Fxfb and Fxrb applied to the wheels 11 and 12 change. That is, by changing the third relationship, the transition of the vehicle braking force Fx can be changed. Therefore, in the present embodiment, the assisting device 90 corresponds to the "braking relationship adjusting unit" that changes the third relationship.

The relationship setting unit 356 of the control device 35 sets the third relationship based on the traveling mode selected through the operation of the operation unit 121. Then, the relationship setting unit 356 controls each of the electric motors 93 and 94 so as to satisfy the set third relationship when the driver is performing the braking operation.

In the present embodiment, the required braking force deriving unit 351 derives a larger value as the required vehicle braking force FxR as the operation amount SBP increases.
In FIG. 15, the third reference relation CR30, which is the reference of the third relation, is shown by a solid line, the third sudden braking relation CR31 is shown by a two-dot chain line, and the third slow braking relation CR32 is shown by a broken line. Has been done. The third reference relationship CR30 is a third relationship when the normal mode is selected as the traveling mode. The third sudden braking relationship CR31 is a third relationship when the sporty mode is selected as the traveling mode. The third slow braking relationship CR32 is a third relationship when the luxury mode is selected as the traveling mode.

As shown by the solid line in FIG. 15, the third reference relationship CR30 is a relationship in which the manipulated variable SBP is increased substantially linearly with respect to the increase in the operating force PBP.
As shown by the alternate long and short dash line in FIG. 15, when the operating force PBP is not so large, the operating force PBP is compared with the case where the third reference relationship CR30 is set as the third relationship. This is the third relationship in which the operation amount SBP is increased and the vehicle braking force Fx is increased even if they are the same. However, in the third sudden braking-related CR31, when the operating force PBP becomes large to some extent, the operating amount SBP becomes higher even if the operating force PBP is the same, as compared with the case where the third reference-related CR30 is set as the third relationship. This is the third relationship that does not grow.

As shown by the broken line in FIG. 15, when the operating force PBP is not so large, the third slow braking relationship CR32 has the same operating force PBP as compared with the case where the third reference relationship CR30 is set as the third relationship. Even so, it is the third relationship that reduces the operation amount SBP and, by extension, the vehicle braking force Fx. However, in the third slow braking relationship CR32, when the operating force PBP becomes large to some extent, the operating amount SBP becomes higher even if the operating force PBP is the same, as compared with the case where the third reference relationship CR30 is set as the third relationship. This is the third relationship that grows.

Next, the above step S12 for deriving the required pitching moment MpR will be described. In this embodiment, step S12 is executed by the target setting unit 352.
In step S12, in the first step S121, the required pitching moment reference value MpB is derived as in the second embodiment. Subsequently, in the next step S122, the pitching moment correction value Mpa is derived. In the next step S123, a value obtained by subtracting the pitching moment correction value Mpa from the required pitching moment reference value MpB is calculated as the required pitching moment MpR. Then, in the next step S124, the smaller the required pitching moment MpR, the larger the value is calculated as the target pitch angle APTr. When the target pitch angle APTr is calculated, the process of step S12 is completed, and the process shifts to the step S13.

Next, with reference to FIGS. 15 and 16, the specific processing contents of step S122 will be described.
In step S122, the required vehicle braking force FxR is acquired, and the operating force PBP input to the braking operating member 321 is acquired. In addition, the operation amount SBP of the braking operation member 321 is acquired. Then, under the assumption that the third reference relation CR30 is set as the third relation, as shown in FIG. 15, the operating force PBP corresponding to the current manipulated variable SBP is derived as the reference operating force PBP1B.

Subsequently, the value obtained by subtracting the reference operating force PBP1B from the current operating force PBP is calculated as the operating force difference ΔPBP1. For example, when the third reference relation CR30 is set as the third relation, the operating force difference ΔPBP1 is “0” because the current operating force PBP is equal to the reference operating force PBP1B. When the third sudden braking relationship CR31 is set as the third relationship, the operating force difference ΔPBP1 is a negative value because the current operating force PBP is smaller than the reference operating force PBP1B. When the third slow braking relationship CR32 is set as the third relationship, the operating force difference ΔPBP1 is a positive value because the current operating force PBP is larger than the reference operating force PBP1B.

Then, the third correction value Mpa3 is derived based on the calculated operating force difference ΔPBP1. That is, when the operating force difference ΔPBP1 is large, a value larger than when the operating force difference ΔPBP1 is small is derived as the third correction value Mpa3. When the third correction value Mpa3 is derived in this way, the larger the third correction value Mpa3 is, the larger the value is derived as the pitching moment correction value Mpa. In the present embodiment, the third correction value Mpa3 is set as the pitching moment correction value Mpa.

According to step S12, the larger the pitching moment correction value Mpa, the smaller the required pitching moment MpR. The smaller the required pitching moment MpR, the larger the target pitch angle APTr. Therefore, when the operating force difference ΔPBP1 is a positive value because the third relationship is the third slow braking relationship CR32, the operating force difference ΔPBP1 is “0” because the third relationship is the third reference relationship CR30. The target pitch angle APTr becomes larger than in the case of. On the other hand, when the operating force difference ΔPBP1 is a negative value because the third relationship is the third sudden braking relationship CR31, the operating force difference ΔPBP is “0” because the third relationship is the third reference relationship CR30. The target pitch angle APTr becomes smaller than in the case of.

In FIG. 16, an example of a map for deriving the third correction value Mpa3 based on the operating force difference ΔPBP1 is shown by a solid line. In the map MAP31 shown by the solid line in FIG. 16, the larger the operating force difference ΔPBP1 is, the larger the value is derived as the third correction value Mpa3. That is, when the operating force difference ΔPBP1 is “0”, “0” is derived as the third correction value Mpa3. When the operating force difference ΔPBP1 is a positive value, a positive value is derived as the third correction value Mpa3. Specifically, the larger the operating force difference ΔPBP1, the larger the third correction value Mpa3. On the other hand, when the operating force difference ΔPBP1 is a negative value, a negative value is derived as the third correction value Mpa3. Specifically, the larger the absolute value of the operating force difference ΔPBP1, the larger the absolute value of the third correction value Mpa3.

According to this embodiment, in addition to the effects described in the first embodiment, the following effects can be further obtained.
In the vehicle 10 provided with the braking device 30, the larger the vehicle braking force Fx, the larger the target pitch angle APTr. Therefore, when the third slow braking relationship CR32 is set as the third relationship, it is difficult to increase the vehicle braking force Fx because the operation amount SBP is unlikely to increase. Therefore, it is difficult for the vehicle 10 to make a pitching motion toward the nose dive side when the vehicle is braked. That is, the pitching posture of the vehicle 10 is unlikely to change.

In the present embodiment, when the third slow braking relation CR32 is set as the third relation, the required pitching moment MpR is increased as compared with the case where the third reference relation CR30 is set as the third relation. It is suppressed. As a result, when the third slow braking relation CR32 is set as the third relation, even if the vehicle braking force Fx is the same because the operation amount SBP is the same, the third reference relation CR30 is set as the third relation. The target pitch angle APTr can be increased as compared with the case where is set. That is, when the third slow braking relationship CR32 is set as the third relationship, the pitching posture of the vehicle 10 can be changed at an early stage. Therefore, when the third slow braking relationship CR32 is set as the third relationship, it is possible to prevent the driver from determining that the vehicle 10 is a vehicle that does not respond well to the braking operation.

On the other hand, in the present embodiment, when the third sudden braking relation CR31 is set as the third relation, the required pitching moment MpR is compared with the case where the third reference relation CR30 is set as the third relation. Growth is encouraged. As a result, when the third sudden braking relation CR31 is set as the third relation, even if the vehicle braking force Fx is the same because the operation amount SBP is the same, the third reference relation CR30 is set as the third relation. The increase in the target pitch angle APTr is suppressed as compared with the case where is set. That is, when the third sudden braking relationship CR31 is set as the third relationship, it is possible to prevent the pitch angle AP of the vehicle 10 from becoming too large or the pitch angle AP changing speed becoming too high.

(7th Embodiment)
Next, a seventh embodiment of the vehicle braking device will be described with reference to FIG. In the present embodiment, the content of the process of correcting the required pitching moment MpR based on the set third relationship is different from that of the sixth embodiment. In the following description, the parts that are different from each of the above embodiments will be mainly described, and the same or corresponding member configurations as those of each of the above embodiments will be designated by the same reference numerals and duplicate description will be omitted. To do.

Even in the assisting device 90 applied to the braking device 30 of the present embodiment, the third relationship can be changed as in the case of the sixth embodiment.
Next, in step S122, the process of deriving the pitching moment correction value Mpa and the third correction value Mpa3 will be described. In this embodiment, step S122 is executed by the target setting unit 352.

In step S122, the required vehicle braking force FxR and the reference operating force PBP1B are derived. Subsequently, the value obtained by subtracting the reference operating force PBP1B from the current operating force PBP is calculated as the operating force difference ΔPBP1. Then, the third correction value Mpa3 is derived based on the calculated operating force difference ΔPBP1. In the present embodiment, when the operating force difference ΔPBP1 is small, a value larger than when the operating force difference ΔPBP1 is large is derived as the third correction value Mpa3. Then, the larger the third correction value Mpa3 is, the larger the value is derived as the pitching moment correction value Mpa. In the present embodiment, the third correction value Mpa3 is set as the pitching moment correction value Mpa.

In FIG. 16, an example of a map for deriving the third correction value Mpa3 based on the operating force difference ΔPBP1 is shown by a broken line. In the map MAP 32 shown by the broken line in FIG. 16, the smaller the operating force difference ΔPBP1, the larger the value is derived as the third correction value Mpa3. That is, when the operating force difference ΔPBP1 is “0”, “0” is derived as the third correction value Mpa3. When the operating force difference ΔPBP1 is a negative value, a positive value is derived as the third correction value Mpa3. Specifically, the larger the absolute value of the operating force difference ΔPBP1, the larger the third correction value Mpa3. On the other hand, when the operating force difference ΔPBP1 is a positive value, a negative value is derived as the third correction value Mpa3. Specifically, the larger the operating force difference ΔPBP1, the larger the absolute value of the third correction value Mpa3.

According to this embodiment, in addition to the effects described in the first embodiment, the following effects can be further obtained.
When the third sudden braking relation CR31 is set as the third relation, the required pitching moment MpR is less likely to increase as compared with the case where the third reference relation CR30 is set as the third relation. As a result, when the third sudden braking relation CR31 is set as the third relation, even if the vehicle braking force Fx is the same because the operation amount SBP is the same, the third reference relation CR30 is set as the third relation. The target pitch angle APTr can be increased as compared with the case where is set. That is, when the third sudden braking relation CR31 is set as the third relation, the pitch angle AP of the vehicle 10 can be increased at an early stage. As a result, it is possible to increase the pitch angle AP of the vehicle 10 to some extent at the initial stage of vehicle braking, and then decelerate the vehicle 10 while maintaining a state in which the pitch angle AP is large.

On the other hand, when the third slow braking relation CR32 is set as the third relation, the increase in the required pitching moment MpR is promoted as compared with the case where the third reference relation CR30 is set as the third relation. .. As a result, when the third slow braking relation CR32 is set as the third relation, even if the vehicle braking force Fx is the same because the operation amount SBP is the same, the third reference relation CR30 is set as the third relation. The increase in the target pitch angle APTr is suppressed as compared with the case where is set. That is, when the third slow braking relationship CR32 is set as the third relationship, the change in the pitching posture of the vehicle 10 during vehicle braking can be suppressed.

(8th Embodiment)
Next, an eighth embodiment of the vehicle braking device will be described with reference to FIG. The present embodiment is different from the first embodiment and the second embodiment in that the target pitch angle APTr is gradually increased during vehicle braking. In the following description, the parts that are different from each of the above embodiments will be mainly described, and the same or corresponding member configurations as those of each of the above embodiments will be designated by the same reference numerals and duplicate description will be omitted. To do.

In the present embodiment, when the required pitching moment MpR is derived, the processing as shown in FIG. 11 is executed by the target setting unit 352. That is, when the required pitching moment reference value MpB is derived in step S121, the pitching moment correction value Mpa is derived in the next step S122. Then, in step S123, a value obtained by subtracting the pitching moment correction value Mpa from the required pitching moment reference value MpB is calculated as the required pitching moment MpR.

Next, with reference to FIG. 17, the derivation process of the pitching moment correction value Mpa will be described. Also in this embodiment, the target setting unit 352 executes the derivation process of the pitching moment correction value Mpa.

As shown in FIG. 17A, the transition of the required vehicle braking force FxR is acquired as the vehicle braking force Fx. Then, the required vehicle braking force FxR to be acquired is filtered, and the value after the filtering is derived as the filtered vehicle braking force FxA.

The filter process executed in the present embodiment is a process of blocking changes outside the predetermined frequency range. For example, in a predetermined frequency range, the vehicle braking force Fx is constant when the driver holds the braking operation, or a slight slow change in the vehicle braking force Fx is detected, but the driver consciously detects it. It is set to block the change in the vehicle braking force Fx when the vehicle braking force Fx is changed. Therefore, when the vehicle braking force Fx fluctuates as before the timing t11, “0” is derived as the filtered vehicle braking force FxA. On the other hand, when the vehicle braking force Fx does not fluctuate as in the timing t11 or later, the filtered vehicle braking force FxA starts to increase. That is, after the timing t11, the filtered vehicle braking force FxA gradually increases with the passage of time.

Then, as shown in FIGS. 17A and 17B, when the filtered vehicle braking force FxA is less than the determination braking force FxTh, "0" is derived as the pitching moment correction value Mpa. In the example shown in FIG. 17, the vehicle braking force FxA after filtering reaches the determined braking force FxTh at the timing t12. Therefore, after the timing t12, a positive value is derived as the pitching moment correction value Mpa. That is, after the timing t12, the pitching moment correction value Mpa gradually increases as time elapses.

For example, when the value obtained by subtracting the determined braking force FxTh from the filtered vehicle braking force FxA is a positive value, the larger the value obtained by subtracting the determined braking force FxTh from the filtered vehicle braking force FxA, the greater the pitching moment correction value Mpa. You may try to make it larger. When the filtered vehicle braking force FxA is equal to or greater than the determined braking force FxTh, the pitching moment correction value Mpa is increased in proportion to the elapsed time from the time when the filtered vehicle braking force FxA reaches the determined braking force FxTh. It may be.

When a positive value is derived as the pitching moment correction value Mpa in this way, the required pitching moment MpR becomes smaller than in the case where the pitching moment correction value Mpa is "0". As a result, the target pitch angle APTr becomes large.

In the present embodiment, when the required pitching moment MpR becomes smaller, the distribution ratio deriving unit 353 causes the front-rear braking force distribution ratio n, the friction regeneration distribution ratio nf of the front wheels 11, and the friction regeneration distribution ratio nr of the rear wheels 12 to be at least one. The distribution ratio is changed. Then, the front wheel friction braking force required value FxfbR, the rear wheel friction braking force required value FxrbR, the front wheel regenerative braking force required value FxfdR, and the rear wheel regenerative braking force required value FxrdR are adjusted, which are derived by the operation instruction unit 354. Then, based on each of these required braking force values FxfbR, FxrbR, FxfdR, and FxrdR, the motor generators 51F, 51R and the braking actuator 33 operate to increase the pitch angle AP of the vehicle 10 while maintaining the vehicle braking force Fx. growing.

That is, the fact that the vehicle braking force FxA after the filter starts to increase can be determined that the vehicle braking force Fx is held. In the present embodiment, when it is determined that the vehicle braking force Fx is held, a positive value is derived as the pitching moment correction value Mpa. As a result, the target setting unit 352 can reduce the required pitching moment MpR and, by extension, increase the target pitch angle APTr. That is, at the time of vehicle braking, the target setting unit 352 can increase the target pitch angle APTr according to the passage of time from the start time of vehicle braking. Therefore, by increasing the pitch angle AP of the vehicle 10 while maintaining the vehicle braking force Fx, it is possible to give the driver a feeling that the deceleration of the vehicle 10 has increased.

(9th Embodiment)
Next, a ninth embodiment of the vehicle braking device will be described with reference to FIG. In the present embodiment, the content of the process of gradually increasing the target pitch angle APTr during vehicle braking is different from that of the eighth embodiment. In the following description, the parts that are different from each of the above embodiments will be mainly described, and the same or corresponding member configurations as those of each of the above embodiments will be designated by the same reference numerals and duplicate description will be omitted. To do.

The derivation process of the pitching moment correction value Mpa will be described with reference to FIG. In the present embodiment, the processing routine is repeatedly executed by the target setting unit 352 when the vehicle is braked.

In this processing routine, in step S51, it is determined whether or not there is a braking request. For example, it is possible to determine whether or not there is a braking request based on the operation amount SBP of the braking operation member 321 and the operation force PBP input to the braking operation member 321. Of course, during automatic braking, it can be determined that there is a braking request when there is a deceleration request from another control device that controls automatic driving.

If it is not determined that there is a braking request (S51: NO), the process proceeds to the next step S52. In step S52, the elapsed time TM from the time when it is determined that there is a braking request is reset to "0". After that, the process proceeds to step S55, which will be described later.

On the other hand, if it is determined in step S51 that there is a braking request (YES), the process proceeds to the next step S53. In step S53, the elapsed time TM is updated. Subsequently, in step S54, it is determined whether or not the updated elapsed time TM is longer than the determination elapsed time TMTh.

Here, in the initial stage of vehicle braking, the required vehicle braking force FxR is increased. Then, when the required vehicle braking force FxR reaches a certain level, the required vehicle braking force FxR is substantially maintained.

Therefore, in the present embodiment, the determination elapsed time TMTh is set as a criterion for determining whether or not the vehicle speed VS has decreased due to vehicle braking, and as a criterion for determining whether or not to increase and correct the target pitch angle APTr. There is. Then, in step S54, when the elapsed time TM is equal to or less than the determined elapsed time TMTh (NO), the process proceeds to the next step S55.

In step S55, “0” is derived as the pitching moment correction value Mpa. In this case, the increase correction of the target pitch angle APTr is not performed. Then, this processing routine is temporarily terminated.

On the other hand, in step S54, when the elapsed time TM is longer than the determined elapsed time TMTh (YES), the process proceeds to the next step S56. In step S56, a positive value is derived as the pitching moment correction value Mpa. For example, the product of the value obtained by subtracting the determination elapsed time TMTh from the elapsed time TM and the gain value Gain is calculated as the pitching moment correction value Mpa. After that, this processing routine is temporarily terminated.

When the pitching moment correction value Mpa is derived in this way, the required pitching moment MpR is reduced and corrected. As a result, the target pitch angle APTr becomes large. That is, at the time of vehicle braking, the target setting unit 352 increases the target pitch angle APTr as the vehicle speed VS decreases from the start time of vehicle braking.

In the present embodiment, when the required pitching moment MpR becomes smaller, the distribution ratio deriving unit 353 causes the front-rear braking force distribution ratio n, the friction regeneration distribution ratio nf of the front wheels 11, and the friction regeneration distribution ratio nr of the rear wheels 12 to be at least one. The distribution ratio is changed. Then, the front wheel friction braking force required value FxfbR, the rear wheel friction braking force required value FxrbR, the front wheel regenerative braking force required value FxfdR, and the rear wheel regenerative braking force required value FxrdR are adjusted, which are derived by the operation instruction unit 354. Then, based on each of these required braking force values FxfbR, FxrbR, FxfdR, and FxrdR, the motor generators 51F, 51R and the braking actuator 33 operate to increase the pitch angle AP of the vehicle 10 while maintaining the vehicle braking force Fx. growing.

Therefore, in the present embodiment, by increasing the pitch angle AP of the vehicle 10 while maintaining the vehicle braking force Fx, it is possible to give the driver a feeling that the deceleration of the vehicle 10 has increased.

(10th Embodiment)
Next, a tenth embodiment of the vehicle braking device will be described with reference to FIG. The present embodiment is different from the eighth embodiment in that the vehicle braking force is also increased when the target pitch angle APTr is gradually increased during vehicle braking. In the following description, the parts that are different from each of the above embodiments will be mainly described, and the same or corresponding member configurations as those of each of the above embodiments will be designated by the same reference numerals and duplicate description will be omitted. To do.

In the present embodiment, when it is determined that the required vehicle braking force FxR is held during vehicle braking, the required vehicle braking force FxR is increased by the required braking force deriving unit 351. For example, the required vehicle braking force FxR is gradually increased so that the amount of increase in the required vehicle braking force FxR becomes a predetermined offset braking force ΔFxR.

When the required vehicle braking force FxR is increased in this way, the target pitch angle APTr and the required pitching moment MpR are changed by the target setting unit 352. That is, the target pitch angle APTr is increased as the required vehicle braking force FxR increases. Then, the required pitching moment MpR decreases as the target pitch angle APTr increases.

When the required pitching moment MpR is derived, the distribution ratio derivation unit 353 derives the front-rear braking force distribution ratio n, the friction regenerative distribution ratio nf of the front wheels 11, and the friction regenerative distribution ratio nr of the rear wheels 12. At this time, the front-rear braking force distribution ratio n and the friction regeneration distribution ratios nf and nr are derived so as to satisfy the following conditions.
-Increase the pitch angle AP of the vehicle 10 as the target pitch angle APTr increases.
-The sum of the front wheel regenerative braking force required value FxfdR and the rear wheel regenerative braking force required value FxrdR is larger than the amount of increase in the required vehicle braking force FxR.

Motor generators 51F, 51R and braking actuators based on the front wheel friction braking force required value FxfbR, the rear wheel friction braking force required value FxrbR, the front wheel regenerative braking force required value FxfdR, and the rear wheel regenerative braking force required value FxrdR derived in this way. By operating 33, the pitch angle AP of the vehicle 10 can be increased while increasing the vehicle braking force Fx.

FIG. 19 shows an example in which the target pitch angle APTr is increased as described above. As shown in FIGS. 19A and 19B, when the braking operation is started at the timing t20, the required vehicle braking force FxR is increased in accordance with the increase in the operation amount SBP of the braking operation member 321. Then, after the timing t21, since the operation amount SBP is held, the required vehicle braking force FxR is held. At the timing t22 under the condition that it is determined that the required vehicle braking force FxR is held, the required vehicle braking force FxR is increased even though the operation amount SBP is held.

Then, the front-rear braking force distribution ratio n, the friction regeneration distribution ratio nf of the front wheels 11, and the friction regeneration distribution ratio nr of the rear wheels 12 are changed in accordance with the increase in the required vehicle braking force FxR. At this time, the front-rear braking force distribution ratio n and each friction regeneration distribution ratio are such that the sum of the front wheel regenerative braking force required value FxfdR and the rear wheel regenerative braking force required value FxrdR is larger than the increase in the required vehicle braking force FxR. nf and nr are adjusted.

Thereby, in the present embodiment, it is possible to realize the build-up of the vehicle braking force Fx while controlling the pitching posture of the vehicle 10. Further, when the vehicle braking force Fx is built up in this way, the regenerative braking force of the vehicle 10 as a whole can be further increased. As a result, the amount of power generated during vehicle braking can be increased.

(Change example)
Each of the above embodiments can be modified and implemented as follows. Each of the above embodiments and the following modified examples can be implemented in combination with each other within a technically consistent range.

In the tenth embodiment, the required vehicle braking force FxR may be continuously increased during the period in which the operation amount SBP is held even after the timing t22.
-In the period in which it is determined that the vehicle braking force Fx is held in the eighth embodiment and the ninth embodiment, when the pitching moment correction value Mpa reaches the threshold value, the pitching moment correction value Mpa is set to the threshold value. It may be held by.

-In the second to seventh embodiments, any one of the first relationship, the second relationship, and the third relationship is set as the change target relationship, and it depends on what kind of relationship the change target relationship is. The target pitch angle APTr and the required pitching moment MpR are derived. However, any two of the first relation, the second relation, and the third relation may be the relations to be changed. For example, when the first relation and the second relation are the relations to be changed, the pitching moment correction value Mpa is set to a value corresponding to the sum of the first correction value Mpa1 and the second correction value Mpa2. .. Further, any of the first relation, the second relation and the third relation may be the relation to be changed. In this case, as the pitching moment correction value Mpa, a value corresponding to the sum of the first correction value Mpa1, the second correction value Mpa2, and the third correction value Mpa3 is set.

In each of the above embodiments, when the maximum value Jfmax of the front wheel coefficient is larger than the maximum value Jrmax of the rear wheel coefficient (S22: NO), in step S25, after "Jr" of the above relational expression (Equation 19). By substituting the maximum value Jrmax of the coefficient for wheels, the friction regeneration distribution ratio nr is calculated. Further, in the next step S26, the friction regeneration distribution ratio nf is calculated by substituting a value equal to the maximum value Jrmax of the rear wheel coefficient as “Jf” in the above relational expression (Equation 18). However, in step S25, the friction regeneration distribution ratio nr is derived by substituting a value smaller than the maximum value Jrmax for the rear wheel and larger than "0" into "Jr" in the above relational expression (Equation 19). You may try to do it. In this case, in the next step S26, the friction regeneration distribution ratio nf is obtained by substituting the value assigned to “Jr” into “Jf” when calculating the friction regeneration distribution ratio nr in the above relational expression (Equation 18). It will be calculated.

In each of the above embodiments, when the maximum value Jfmax of the front wheel coefficient is equal to or less than the maximum value Jrmax of the rear wheel coefficient (S22: YES), in step S23, the front wheel is set to "Jf" in the above relational expression (Equation 18). The friction regeneration distribution ratio nf is calculated by substituting the maximum value Jfmax of the coefficient. Further, in the next step S24, the friction regeneration distribution ratio nr is calculated by substituting a value equal to the maximum value Jfmax of the front wheel coefficient as “Jr” in the above relational expression (Equation 19). However, in step S23, the friction regeneration distribution ratio nf is derived by substituting a value smaller than the maximum value Jfmax for the front wheels and larger than "0" into "Jf" in the above relational expression (Equation 18). You may do so. In this case, in the next step S24, the friction regeneration distribution ratio nr is calculated by substituting the value assigned to “Jf” into “Jr” when calculating the friction regeneration distribution ratio nf in the above relational expression (Equation 19). It will be calculated.

-In the second embodiment, when the first relationship is adjusted to the first slow braking relationship CR12, the target pitch is higher than when the first relationship is adjusted to the relationships CR10 and CR11 other than the first slow braking relationship CR12. If the angle APTr can be increased, the first correction value Mpa1 may be derived so as to be different from the above embodiment. For example, when the manipulated variable ΔSBP is larger than “0”, a positive value is derived as the first correction value Mpa1, while when the manipulated variable ΔSBP is “0” or less, the first correction value Mpa1 is “0”. May be derived.

-In the third embodiment, when the first relationship is adjusted to the first sudden braking relationship CR11, the target pitch is higher than when the first relationship is adjusted to the relationships CR10 and CR12 other than the first sudden braking relationship CR11. If the angle APTr can be increased, the first correction value Mpa1 may be derived so as to be different from the above embodiment. For example, when the manipulated variable ΔSBP is smaller than “0”, a positive value is derived as the first correction value Mpa1, while when the manipulated variable ΔSBP is “0” or more, the first correction value Mpa1 is “0”. May be derived.

-In the fourth embodiment, when the second relationship is adjusted to the second slow braking relationship CR22, the target pitch is higher than when the second relationship is adjusted to the relationships CR20 and CR21 other than the second slow braking relationship CR22. If the angle APTr can be increased, the second correction value Mpa2 may be derived so as to be different from the above embodiment. For example, when the operating force difference ΔPBP is larger than “0”, a positive value is derived as the second correction value Mpa2, while when the operating force difference ΔPBP is “0” or less, the second correction value Mpa2 is “0”. May be derived.

-In the fifth embodiment, when the second relationship is adjusted to the second sudden braking relationship CR21, the target pitch is higher than when the second relationship is adjusted to the relationships CR20 and CR22 other than the second sudden braking relationship CR21. If the angle APTr can be increased, the second correction value Mpa2 may be derived so as to be different from the above embodiment. For example, when the operating force difference ΔPBP is smaller than “0”, a positive value is derived as the second correction value Mpa2, while when the operating force difference ΔPBP is “0” or more, the second correction value Mpa2 is “0”. May be derived.

-In the sixth embodiment, when the third relationship is adjusted to the third slow braking relationship CR32, the target pitch is higher than when the third relationship is adjusted to the relationships CR30 and CR31 other than the third slow braking relationship CR32. If the angle APTr can be increased, the third correction value Mpa3 may be derived so as to be different from the above embodiment. For example, when the operating force difference ΔPBP1 is larger than “0”, a positive value is derived as the third correction value Mpa3, while when the operating force difference ΔPBP1 is “0” or less, the third correction value Mpa3 is “0”. May be derived.

-In the seventh embodiment, when the third relationship is adjusted to the third sudden braking relationship CR31, the target pitch is higher than when the third relationship is adjusted to the relationships CR30 and CR32 other than the third sudden braking relationship CR31. If the angle APTr can be increased, the third correction value Mpa3 may be derived so as to be different from the above embodiment. For example, when the operating force difference ΔPBP1 is smaller than “0”, a positive value is derived as the third correction value Mpa3, while when the operating force difference ΔPBP1 is “0” or more, the third correction value Mpa3 is “0”. May be derived.

-In each of the above embodiments, the required pitching is performed after deriving the maximum value FADMAX of the anti-dive force FAD, the maximum value FALMAX of the anti-lift force FAL, the minimum value FADMIN of the anti-dive force FAD, and the minimum value FALMIN of the anti-lift force FAL. The moment MpR may be derived. As a result, when the front-rear braking force distribution ratio n and the friction regeneration distribution ratios nf and nr are calculated as described above, the distribution ratio of at least one of the distribution ratios n, nf and nr becomes less than "0". Or, it can be suppressed that it becomes larger than "1".

For example, the maximum value FADMAX of anti-dive force, the maximum value FALMAX of anti-lift force, the minimum value FADMIN of anti-dive force, and the minimum value FALMIN of anti-lift force are the following relational expressions (Equation 20), (Equation 21), ( It can be expressed as Equation 22) and (Equation 23).

・車輪１１，１２に摩擦制動力を付与できるのであれば、摩擦制動機構２０Ｆ，２０Ｒは、上記各実施形態で説明した構成とは異なる機能であってもよい。例えば、摩擦制動機構２０Ｆ，２０Ｒは、ホイールシリンダ２１を備えないで、電気モータの駆動量に応じた力で摩擦材２３を回転体２２に押し付ける機構のものであってもよい。こうした制動機構２０Ｆ，２０Ｒとしては、例えば、「特開２０１７−１００５０７号公報」を挙げることができる。

-The friction braking mechanisms 20F and 20R may have functions different from those described in the above embodiments as long as the friction braking force can be applied to the wheels 11 and 12. For example, the friction braking mechanisms 20F and 20R may be of a mechanism that does not include the wheel cylinder 21 and presses the friction material 23 against the rotating body 22 with a force corresponding to the driving amount of the electric motor. Examples of such braking mechanisms 20F and 20R include "Japanese Patent Laid-Open No. 2017-100507".

The braking device 30 may be applied to a vehicle in which the geometry of the suspension for the front wheels 11 and the suspension for the rear wheels 12 satisfies the following conditions. That is, when the front wheel braking force Fxf and the rear wheel braking force Fxr have the same value, the anti-dive force FAD is larger than the anti-lift force FAL.

The control device 35 includes one or more dedicated hardware circuits such as one or more processors that operate according to a computer program, dedicated hardware that executes at least a part of various processes, or a combination thereof. It can be configured as a circuit. As the dedicated hardware, for example, an ASIC which is an integrated circuit for a specific application can be mentioned. The processor includes a CPU and a memory such as a RAM and a ROM, and the memory stores a program code or an instruction configured to cause the CPU to execute a process. Memory or storage medium includes any available medium accessible by a general purpose or dedicated computer.

Next, the technical idea that can be grasped from each of the above embodiments and modification examples will be described.
(B) Applicable to vehicles equipped with a regenerative braking device that adjusts the regenerative braking force applied to at least one of the front and rear wheels of the vehicle.
A friction generating device that adjusts the friction braking force applied to the front wheels and the friction braking force applied to the rear wheels.
The first relationship, which is the relationship between the operating amount of the braking operation member and the braking force of the vehicle, the second relationship, which is the relationship between the operating force input to the braking operation member and the braking force of the vehicle, and the operation. A braking relationship adjusting unit that changes at least one of the third relationships, which is the relationship between the amount and the operating force, and
A control device for controlling the braking force of the vehicle is provided.
When the ratio of the friction braking force applied to the regeneration target wheel to the braking force applied to the regeneration target wheel, which is a wheel capable of applying the regenerative braking force among the front wheels and the rear wheels, is defined as the friction regeneration distribution ratio.
The control device is
A target setting unit that sets a target pitch angle, which is a target of the pitch angle of the vehicle,
A distribution ratio derivation unit that derives the friction regeneration distribution ratio based on the target pitch angle,
At the time of vehicle braking, the friction braking device and the operation instruction unit for instructing the operation of the regenerative braking device are provided based on the target vehicle braking force which is the target of the braking force of the vehicle and the friction regeneration distribution ratio. And
When the relationship changed by the braking relationship adjusting unit among the first relationship, the second relationship, and the third relationship is defined as the relationship to be changed.
When the change target relationship is adjusted to a relationship that reduces the braking force of the vehicle as compared with the case where the change target relationship is a reference relationship, the target setting unit changes the change target relationship. The target pitch angle is made larger than when the relationship is adjusted so as to increase the braking force of the vehicle as compared with the case where the relationship is the reference relationship.

According to the above configuration, when the target pitch angle is set, a value corresponding to the target pitch angle is derived as the friction regeneration distribution ratio. Then, by operating the friction braking device and the regenerative braking device based on the friction regeneration distribution ratio and the target vehicle braking force, it is possible to suppress the deviation between the vehicle pitch angle and the target pitch angle during vehicle braking. Further, when the change target relationship is adjusted to a relationship that reduces the braking force of the vehicle as compared with the case where the change target relationship is the reference relationship, the change target relationship is the change target relationship, and the change target relationship is the reference relationship. A larger value is set as the target pitch angle than when the braking force of the vehicle is adjusted to be larger than in the case of. Therefore, even when the change target relationship is adjusted to reduce the braking force of the vehicle as compared with the case where the change target relationship is the reference relationship, the pitching posture of the vehicle should be changed at an early stage. Can be done. As a result, it is possible to prevent the driver from determining that the vehicle provided with the braking device is a vehicle that does not respond well to the braking operation.

(B) Applicable to vehicles equipped with a regenerative braking device that adjusts the regenerative braking force applied to at least one of the front and rear wheels of the vehicle.
A friction generating device that adjusts the friction braking force applied to the front wheels and the friction braking force applied to the rear wheels.
The first relationship, which is the relationship between the operating amount of the braking operation member and the braking force of the vehicle, the second relationship, which is the relationship between the operating force input to the braking operation member and the braking force of the vehicle, and the operation. A braking relationship adjusting unit that changes at least one of the third relationships, which is the relationship between the amount and the operating force, and
A control device for controlling the braking force of the vehicle is provided.
When the ratio of the regenerative braking force applied to the regenerative target wheel to the braking force applied to the regenerative target wheel, which is a wheel capable of applying the regenerative braking force among the front wheels and the rear wheels, is defined as the friction regeneration distribution ratio.
The control device is
A target setting unit that sets a target pitch angle, which is a target of the pitch angle of the vehicle,
A distribution ratio derivation unit that derives the friction regeneration distribution ratio based on the target pitch angle,
At the time of vehicle braking, the friction braking device and the operation instruction unit for instructing the operation of the regenerative braking device are provided based on the target vehicle braking force which is the target of the braking force of the vehicle and the friction regeneration distribution ratio. And
When the relationship changed by the braking relationship adjusting unit among the first relationship, the second relationship, and the third relationship is defined as the relationship to be changed.
When the change target relationship is adjusted so that the braking force of the vehicle is increased as compared with the case where the change target relationship is the reference relationship, the target setting unit changes the change target relationship. The target pitch angle is made larger than when the relation is adjusted so as to reduce the braking force of the vehicle as compared with the case where the relation is the reference relation.

According to the above configuration, when the target pitch angle is set, a value corresponding to the target pitch angle is derived as the friction regeneration distribution ratio. Then, by operating the friction braking device and the regenerative braking device based on the friction regeneration distribution ratio and the target vehicle braking force, it is possible to suppress the deviation between the vehicle pitch angle and the target pitch angle during vehicle braking. Further, when the change target relationship is adjusted to a relationship in which the braking force of the vehicle is increased as compared with the case where the change target relationship is the reference relationship, the change target relationship is the change target relationship, and the change target relationship is the reference relationship. A larger value is set as the target pitch angle than when the braking force of the vehicle is adjusted to be smaller than in the case of. Therefore, when the change target relationship is adjusted to increase the braking force of the vehicle as compared with the case where the change target relationship is the reference relationship, the pitch angle AP of the vehicle is adjusted at the initial stage of vehicle braking. After that, it becomes possible to decelerate the vehicle while maintaining a state in which the pitch angle is large.

(C) Applicable to vehicles equipped with a regenerative braking device that adjusts the regenerative braking force applied to at least one of the front and rear wheels of the vehicle.
A friction generating device for adjusting the friction braking force applied to the front wheels and the friction braking force applied to the rear wheels, and a control device for controlling the braking force of the vehicle are provided.
When the ratio of the regenerative braking force applied to the regenerative target wheel to the braking force applied to the regenerative target wheel, which is a wheel capable of applying the regenerative braking force among the front wheels and the rear wheels, is defined as the friction regeneration distribution ratio.
The control device is
A target setting unit that sets a target pitch angle, which is a target of the pitch angle of the vehicle,
A distribution ratio derivation unit that derives the friction regeneration distribution ratio based on the target pitch angle,
At the time of vehicle braking, the friction braking device and the operation instruction unit for instructing the operation of the regenerative braking device are provided based on the target vehicle braking force which is the target of the braking force of the vehicle and the friction regeneration distribution ratio. And
At the time of vehicle braking, the target setting unit increases the target pitch angle according to the elapsed time from the start time of vehicle braking or the decrease in the vehicle body speed from the start time of vehicle braking.

According to the above configuration, when the target pitch angle is set, a value corresponding to the target pitch angle is derived as the friction regeneration distribution ratio. Then, by operating the friction braking device and the regenerative braking device based on the friction regeneration distribution ratio and the target vehicle braking force, it is possible to suppress the deviation between the vehicle pitch angle and the target pitch angle during vehicle braking. Further, in the above configuration, at the time of vehicle braking, the target pitch angle is increased according to the elapsed time from the start time of vehicle braking or the decrease of the vehicle body speed from the start time of vehicle braking. When the target pitch angle is increased in this way, the friction regeneration distribution ratio is adjusted in conjunction with the increase in the target pitch angle. As a result, the pitch angle of the vehicle can be increased during vehicle braking. As a result, it is possible to give the driver the feeling that the deceleration of the vehicle has increased.

10 ... vehicle, 11 ... front wheel, 12 ... rear wheel, 50 ... regenerative braking device, 30 ... braking device, 31 ... friction braking device, 321 ... braking operation member, 35 ... control device, 352 ... target setting unit, 353 ... distribution Ratio derivation unit, 354 ... Operation instruction unit, 90 ... Auxiliary device which is an example of a braking-related adjustment unit.

Claims (8)

Applicable to vehicles equipped with a regenerative braking device that adjusts the regenerative braking force applied to at least one of the front and rear wheels of the vehicle.
A friction braking device for adjusting the friction braking force applied to the front wheels and the friction braking force applied to the rear wheels, and a control device for controlling the braking force of the vehicle are provided.
The ratio of the braking force applied to the front wheels to the sum of the braking force applied to the front wheels and the braking force applied to the rear wheels is defined as the front-rear braking force distribution ratio, and the regenerative braking force of the front wheels and the rear wheels is defined as the front-rear braking force distribution ratio. When the ratio of the friction braking force applied to the regeneration target wheel to the braking force applied to the regeneration target wheel, which is a wheel that can be applied, is defined as the friction regeneration distribution ratio.
The control device is
Based on the target of the pitching posture of the vehicle, the distribution ratio derivation unit for deriving the front-rear braking force distribution ratio and the friction regeneration distribution ratio,
An operation instruction unit that instructs the operation of the friction braking device and the regenerative braking device based on the target vehicle braking force that is the target of the braking force of the vehicle, the front-rear braking force distribution ratio, and the friction regeneration distribution ratio. Vehicle braking device, including. The target of the pitching posture of the vehicle is the target pitch angle which is the target of the pitch angle of the vehicle.
The vehicle braking device according to claim 1, wherein the distribution ratio derivation unit reduces the friction regeneration distribution ratio as the target pitch angle increases. The vehicle according to claim 1 or 2, wherein the distribution ratio derivation unit derives a value that maximizes the regenerative braking force applied to the regeneration target wheel as the front-rear braking force distribution ratio and the friction regeneration distribution ratio. Braking device. The relationship between the operating amount of the braking operation member and the braking force of the vehicle is the first relationship, and the relationship between the operating force input to the braking operation member and the braking force of the vehicle is the second relationship. When the relationship with the operating force is the third relationship,
A braking relationship adjusting unit that changes at least one of the first relationship, the second relationship, and the third relationship is provided.
The control device has a target setting unit that sets a target pitch angle, which is a target of the pitch angle of the vehicle, as a target of the pitching posture of the vehicle.
When the relationship changed by the braking relationship adjusting unit among the first relationship, the second relationship, and the third relationship is defined as the relationship to be changed.
When the change target relationship is adjusted to a relationship that reduces the braking force of the vehicle as compared with the case where the change target relationship is a reference relationship, the target setting unit changes the change target relationship. In any one of claims 1 to 3, the target pitch angle is made larger than when the relationship is adjusted to increase the braking force of the vehicle as compared with the case where the relationship is the reference relationship. The vehicle braking device described. The relationship between the operating amount of the braking operation member and the braking force of the vehicle is the first relationship, and the relationship between the operating force input to the braking operation member and the braking force of the vehicle is the second relationship. When the relationship with the operating force is the third relationship,
A braking relationship adjusting unit that changes at least one of the first relationship, the second relationship, and the third relationship is provided.
The control device has a target setting unit that sets a target pitch angle, which is a target of the pitch angle of the vehicle, as a target of the pitching posture of the vehicle.
When the relationship changed by the braking relationship adjusting unit among the first relationship, the second relationship, and the third relationship is defined as the relationship to be changed.
When the change target relationship is adjusted so that the braking force of the vehicle is increased as compared with the case where the change target relationship is the reference relationship, the target setting unit changes the change target relationship. According to any one of claims 1 to 3, the target pitch angle is made larger than when the relation is adjusted so as to reduce the braking force of the vehicle as compared with the case where the relation is the reference relation. The vehicle braking device described. The control device has a target setting unit that sets a target pitch angle, which is a target of the pitch angle of the vehicle, as a target of the pitching posture of the vehicle.
Claims 1 to claim that the target setting unit increases the target pitch angle at the time of vehicle braking according to the passage of time from the start time of vehicle braking or the decrease of the vehicle body speed of the vehicle from the start time of vehicle braking. Item 3. The vehicle braking device according to any one of items 3. When the operation instruction unit determines that the braking force of the vehicle is maintained during vehicle braking, the front-rear braking force distribution ratio and the friction regeneration distribution while maintaining the braking force of the vehicle. The vehicle braking device according to claim 6, which instructs the operation of the friction braking device and the regenerative braking device based on the ratio. When the operation instruction unit determines that the braking force of the vehicle is held during vehicle braking, the front-rear braking force distribution ratio and the friction regeneration distribution are increased while increasing the braking force of the vehicle. Instruct the operation of the friction braking device and the regenerative braking device based on the ratio,
When the distribution ratio derivation unit determines that the braking force of the vehicle is held during vehicle braking, the regenerative braking force applied to the regenerative target wheel is more than the amount of increase in the braking force of the vehicle. The vehicle braking device according to claim 6, wherein the friction regeneration distribution ratio is derived so that the amount of increase is large.

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