JP7091797B2 - Vehicle braking control device - Google Patents

Description

The present invention relates to a vehicle braking control device.

The applicant has developed a braking control device for a vehicle as described in Patent Document 1. In the device, in order to simplify and downsize the mechanical regulator, "a mechanical type that sends out an output pressure according to the pilot pressure supplied to the pilot chamber based on the brake hydraulic pressure of the high pressure source from the output port. The regulator, the switching unit connected to the pilot room, the first pilot pressure generator connected to the pilot room via the switching unit and supplying the first pilot pressure to the pilot room, and the pilot room via the switching unit. It is equipped with a second pilot pressure generator that is connected and supplies the second pilot pressure to the pilot chamber, and a wheel cylinder that generates braking force based on the output pressure supplied from the output port of the mechanical regulator. Is configured to supply either the first pilot pressure or the second pilot pressure to the pilot chamber. "

The applicant has further improved and developed a braking control device as described in Patent Document 2. The device is composed of an electric pump and a solenoid valve, and adjusts the braking liquid discharged by the electric pump to the adjusting hydraulic pressure by the solenoid valve, and introduces the adjusting hydraulic pressure into the rear wheel wheel cylinder. And "A master chamber composed of a master cylinder and a master piston and connected to the front wheel wheel cylinder, and a forward movement facing the retreat force applied to the master piston by the master chamber to which the adjusting hydraulic pressure is introduced." It is configured to include a "master unit having a servo chamber that applies force to the master piston".

In the device, the braking fluid discharged by the electric pump is adjusted to the adjusting hydraulic pressure by the solenoid valve and introduced into the servo chamber and the rear wheel wheel cylinder. In this configuration, the electric pump is stopped during non-braking and rotationally driven during braking. The braking control device is a so-called on-demand type. Therefore, it is desired to improve the boost response during sudden braking.

Japanese Unexamined Patent Publication No. 2013-107561 Japanese Patent Application No. 2017-184272

An object of the present invention is to provide an on-demand type vehicle braking control device capable of improving boost response.

The braking control device SC according to the present invention pumps the braking liquid (BF) to the wheel cylinder (CW) of the wheel (WH) of the vehicle in response to the operation of the braking operation member (BP) of the vehicle, and pumps the braking liquid (BF) to the wheel (BF). A simulator (SS) that generates braking torque in WH) and applies an operating force (Fp) corresponding to the operation to the braking operation member (BP), a "master cylinder (CM), and a master". It faces a master chamber (Rm) composed of a piston (PM) and connected to the wheel cylinder (CW), and a retracting force (Fb) applied to the master piston (PM) by the master chamber (Rm). A master unit (YM) having a servo chamber (Rs) that applies a forward force (Fa) to the master piston (PM), and an electric motor that sucks the braking liquid (BF) from the reservoir (RV) of the vehicle. The braking liquid (BF), which is composed of a pump (DC) and an electromagnetic valve (UA, UB, UC) and is discharged by the electric pump (DC), is adjusted by the electromagnetic valve (UA, UB, UC). A pressure regulating unit (YC) that adjusts to the hydraulic pressure (Pa, Pb, Pc) and introduces the adjusted hydraulic pressure (Pa, Pb, Pc) into the servo chamber (Rs), and the braking operation member (BP). ), And an input cylinder (CN) connected to the simulator (SS) via a simulator fluid path (HS), and the master piston (PM) and the input piston. A regenerative coordination unit (YK) in which the gap (Ks) with (PK) is controlled by the adjusting hydraulic pressure (Pa, Pb, Pc) is provided.

In the braking control device SC according to the present invention, in the simulator fluid path (HS), when the speed (dB) of the operation is equal to or less than the first predetermined value (da), the flow of the braking fluid (BF) is relative to the flow. When the speed (dB) of the operation is greater than or equal to the second predetermined value (db), which is larger than the first predetermined value (da), the resistance to the flow of the braking fluid (BF) is not obtained. An orifice (OR, VA valve seat hole) is provided.

In the orifice characteristic, the internal pressure before and after the orifice (that is, the fluid resistance of the orifice) increases substantially in proportion to the square of the flow rate. According to the above configuration, when the operation speed dB is equal to or less than the first predetermined value da corresponding to the normal braking operation, the orifice OR does not become a resistance to the flow of the braking liquid BF, so that the orifice OR is It does not affect the braking operation characteristics. On the other hand, when the operation speed dB is equal to or higher than the second predetermined value db corresponding to a sudden braking operation, the brake fluid BF becomes difficult to be discharged from the input cylinder CN because it becomes a resistance to the flow of the brake fluid BF. A confined state of the input cylinder CN is formed. Therefore, since the operating force Fp by the driver is transmitted to the master piston PM, the boost response of the master cylinder hydraulic pressure Pm can be improved.

Further, the braking control device SC according to the present invention is provided in the bypass fluid path (HD) connecting the reservoir (RV) and the servo chamber (Rs) and the “bypass fluid path (HD) provided in the reservoir. Allows the movement of the braking fluid (BF) from (RV) to the servo chamber (Rs), but prevents the movement of the braking fluid (BF) from the servo chamber (Rs) to the reservoir (RV). It is equipped with a check valve (GD).

When the braking operation member BP is suddenly operated, a situation may occur in which the increase in the adjusting hydraulic pressure (Pa or the like) is insufficient with respect to the increase in the operating force Fp. According to the above configuration, even if the rise of the adjusting hydraulic pressure is delayed, the braking fluid BF can flow into the servo chamber Rs via the bypass fluid path HD, so that the boost response of the master cylinder hydraulic pressure Pm Sex can be ensured.

It is an overall block diagram for demonstrating the 1st Embodiment of the brake control device SC of the vehicle which concerns on this invention. It is a characteristic figure for demonstrating the operation of the input chamber orifice OR. It is a control flow diagram for demonstrating the process of pressure adjustment control including regenerative coordination control. It is a control flow diagram for demonstrating the processing at the time of a sudden operation. It is an overall block diagram for demonstrating the 2nd Embodiment of the brake control device SC of the vehicle which concerns on this invention.

<Symbols of components, etc. and subscripts at the end of the symbols>
In the following description, components, arithmetic processing, signals, characteristics, and values having the same symbol, such as "ECU", have the same function. The subscripts "i" to "l" attached to the end of the symbol relating to each wheel are comprehensive symbols indicating which wheel it is related to. Specifically, "i" indicates the right front wheel, "j" indicates the left front wheel, "k" indicates the right rear wheel, and "l" indicates the left rear wheel. For example, in each of the four wheel cylinders, it is described as a right front wheel wheel cylinder CWi, a left front wheel wheel cylinder CWj, a right rear wheel wheel cylinder CWk, and a left rear wheel wheel cylinder CWl. Further, the subscripts "i" to "l" at the end of the symbol may be omitted. When the subscripts "i" to "l" are omitted, each symbol represents a general term for each of the four wheels. For example, "WH" represents each wheel and "CW" represents each wheel cylinder.

The subscripts "f" and "r" added to the end of the symbols relating to the two braking systems are comprehensive symbols indicating which system of the front and rear wheels it relates to. Specifically, "f" indicates a front wheel system, and "r" indicates a rear wheel system. For example, in the wheel cylinder CW of each wheel, it is described as front wheel wheel cylinder CWf (= CWi, CWj) and rear wheel wheel cylinder CWr (= CWk, CWl). Further, the subscripts "f" and "r" at the end of the symbol may be omitted. When the subscripts "f" and "r" are omitted, each symbol represents a general term for each of the two braking systems. For example, "CW" represents a wheel cylinder in the front and rear braking system.

<First Embodiment of the vehicle braking control device according to the present invention>
A first embodiment of the braking control device SC according to the present invention will be described with reference to the overall configuration diagram of FIG. In a general vehicle, two fluid paths are adopted to ensure redundancy. The fluid path is a path for moving the brake fluid BF, which is the working liquid of the braking control device SC, and corresponds to a braking pipe, a flow path of a fluid unit, a hose, and the like. The inside of the fluid path is filled with the braking fluid BF. In the braking control device SC, a so-called front-rear type (also referred to as "H type") is adopted as the two fluid paths. The front wheel system is connected to the front wheel cylinder CWf (= CWi, CWj), and the rear wheel system is connected to the rear wheel cylinder CWr (= CWk, CWl). In the fluid path, the side closer to the reservoir RV (the side far from the wheel cylinder CW) is called the "upstream side" or "upper part", and the side closer to the wheel cylinder CW (the side far from the reservoir RV) is "downstream". It is called "side" or "bottom".

The vehicle is equipped with an electric motor GN for driving. That is, the vehicle is a hybrid vehicle or an electric vehicle. The driving electric motor GN also functions as a generator for energy regeneration. For example, the generator GN is provided on the front wheel WHf. The electric motor / generator GN is controlled by the drive controller ECD.

In the braking control device SC, so-called regenerative cooperative control (coordination between regenerative braking and friction braking) is executed. The vehicle equipped with the braking control device SC is provided with a braking operation member BP, a wheel cylinder CW, a reservoir RV, and a wheel speed sensor VW.

The braking operation member (for example, the brake pedal) BP is a member operated by the driver to decelerate the vehicle. By operating the braking operation member BP, the braking torque of the wheel WH is adjusted, and a braking force is generated on the wheel WH. Specifically, a rotating member (for example, a brake disc) KT is fixed to the wheel WH of the vehicle. Then, a brake caliper is arranged so as to sandwich the rotating member KT, and a wheel cylinder CW is provided there. By increasing the pressure (braking fluid pressure) Pw of the braking fluid BF in the wheel cylinder CW, the friction member (for example, the brake pad) is pressed against the rotating member KT. Since the rotating member KT and the wheel WH are fixed so as to rotate integrally, a braking torque (resulting in friction braking force) is generated in the wheel WH by the frictional force generated at this time.

The reservoir (atmospheric pressure reservoir) RV is a tank for the working liquid, and the braking liquid BF is stored in the tank. The lower part of the reservoir RV is divided into a master reservoir chamber Ru connected to the master cylinder chamber Rm and a pressure regulating reservoir chamber Rd connected to the pressure regulating unit YC by a partition plate SK. When the reservoir RV is filled with the braking fluid BF, the liquid level of the braking fluid BF is above the height of the partition plate SK. Therefore, the brake fluid BF can freely move between the master reservoir chamber Ru and the pressure adjusting reservoir chamber Rd beyond the partition plate SK. On the other hand, when the amount of the braking fluid BF in the reservoir RV decreases and the liquid level of the braking fluid BF becomes lower than the height of the partition plate SK, the master reservoir chamber Ru and the pressure regulating reservoir chamber Rd become independent liquid reservoirs. ..

Each wheel WH is provided with a wheel speed sensor VW to detect the wheel speed Vw. The wheel speed Vw signal is used for wheel-independent braking control such as anti-skid control (control to suppress excessive deceleration slip of wheels) and vehicle stabilization control (control to suppress excessive oversteer and understeer behavior). Will be done. The vehicle body speed Vx is calculated based on each wheel speed Vw detected by the wheel speed sensor VW.

≪Brake control device SC≫
The braking control device SC includes an upper fluid unit YU and a lower fluid unit YL. Here, the upper fluid unit YU is a fluid unit on the side closer to the master cylinder CM, and the lower fluid unit YL is a fluid unit on the side closer to the wheel cylinder CW. The inside of each fluid unit YU and YL is made liquidtight by the braking fluid BF. The upper fluid unit YU is controlled by the upper controller ECU, and the lower fluid unit YL is controlled by the lower controller ECL. The upper controller ECU and the lower controller ECL are connected via a communication bus BS so that each signal (sensor detection value, calculated value, etc.) is shared.

The upper fluid unit YU of the braking control device SC is composed of an operation amount sensor BA, an operation switch ST, a stroke simulator SS, a master unit YM, a pressure adjustment unit YC, and a regenerative coordination unit YK.

An operation amount sensor BA is provided so as to detect the operation amount Ba of the braking operation member (brake pedal) BP by the driver. As the operation amount sensor BA, an operation displacement sensor SP for detecting the operation displacement Sp of the braking operation member BP is provided. An operating force sensor FP is provided so as to detect the operating force Fp of the braking operation member BP. Further, as the manipulated variable sensor BA, a simulator hydraulic pressure sensor PS is provided so as to detect the hydraulic pressure (simulator hydraulic pressure) Ps in the stroke simulator SS. An input hydraulic pressure sensor PN is provided so as to detect the hydraulic pressure (input hydraulic pressure) Pn in the input chamber Rn of the regeneration cooperation unit YK. The operation amount sensor BA is a general term for the above-mentioned operation displacement sensor SP and the like, and at least one of the operation displacement Sp, the operation force Fp, the simulator hydraulic pressure Ps, and the input hydraulic pressure Pn is adopted as the braking operation amount Ba. Will be done. The detected braking operation amount Ba is input to the upper controller ECU.

The braking operation member BP is provided with an operation switch ST so as to detect the presence or absence of operation of the braking operation member BP by the driver. When the braking operation member BP is not operated (that is, during non-braking), the braking operation switch ST outputs an off signal as the operation signal St. On the other hand, when the braking operation member BP is operated (that is, during braking), an on signal is output as an operation signal St. The braking operation signal St is input to the controller ECU.

A stroke simulator (simply also referred to as “simulator”) SS is provided to generate an operating force Fp on the braking operating member BP. The simulator SS is connected between the reaction chamber Ro and the first on-off valve VA in the simulator fluid path HS. Inside the simulator SS, a simulator piston Es and an elastic body (for example, a compression spring) Ds are provided. When the brake fluid BF is moved into the simulator SS, the piston Es is pushed by the inflowing brake fluid BF. Since a force is applied to the piston in a direction of blocking the inflow of the braking liquid BF by the elastic body Ds, an operating force Fp when the braking operating member BP is operated is formed. In the simulator SS, an orifice Os is provided at the inlet of the brake fluid BF. The damping generated at the orifice Os improves the operating characteristics of the braking operating member BP.

[Master unit YM]
The master unit YM adjusts the hydraulic pressure (front wheel braking hydraulic pressure) Pwf in the front wheel cylinder CWf via the master cylinder chamber Rm. The master unit YM includes a master cylinder CM, a master piston PM, and a master elastic body SM.

The master cylinder CM is a cylinder member having a bottom portion. The master piston PM is a piston member inserted inside the master cylinder CM, and can move in conjunction with the operation of the braking operation member BP. The inside of the master cylinder CM is divided into three hydraulic chambers Rm, Rs, and Ro by the master piston PM.

A groove is formed in the first inner peripheral portion Mw of the master cylinder CM, and two seal SLs are fitted in the groove. The outer peripheral portion (outer peripheral cylindrical surface) Mp of the master piston PM and the first inner peripheral portion (inner peripheral cylindrical surface) Mw of the master cylinder CM are sealed (sealed) by the two seal SLs. The master piston PM can move smoothly along the central axis Jm of the master cylinder CM.

The master cylinder chamber (simply also referred to as “master chamber”) Rm is determined by “the first inner peripheral portion Mw of the master cylinder CM, the first bottom portion (bottom surface) Mu” and the first end portion Mv of the master piston PM. It is a partitioned hydraulic chamber. A master cylinder fluid path HM is connected to the master chamber Rm, and is finally connected to the front wheel cylinder CWf via the lower fluid unit YL.

The master piston PM is provided with a brim portion (flange) Tm. The inside of the master cylinder CM is divided into a servo hydraulic chamber (simply also referred to as "servo chamber") Rs and a reaction force hydraulic chamber (simply also referred to as "reaction chamber") Ro by the brim portion Tm. There is. A seal SL is provided on the outer peripheral portion of the brim portion Tm, and the brim portion Tm and the second inner peripheral portion Md of the master cylinder CM are sealed. The servo chamber Rs is a hydraulic chamber partitioned by "the second inner peripheral portion Md of the master cylinder CM, the second bottom portion (bottom surface) Mt" and the first surface Ms of the brim portion Tm of the master piston PM. .. The master chamber Rm and the servo chamber Rs are arranged so as to face each other with the master piston PM (particularly, the brim portion Tm) interposed therebetween. The front wheel pressure regulating fluid passage HF is connected to the servo chamber Rs, and the adjusting hydraulic pressure Pa is introduced from the pressure regulating unit YC.

The reaction chamber Ro is a hydraulic chamber partitioned by a second inner peripheral portion Md of the master cylinder CM, a stepped portion Mz, and a second surface Mo of the brim portion Tm of the master piston PM. The reaction chamber Ro is sandwiched between the master hydraulic chamber Rm and the servo hydraulic chamber Rs in the direction of the central axis Jm, and is located between them. Therefore, when the volume Vs of the servo chamber Rs is increased, the volume Vo of the reaction force chamber Ro is decreased. On the contrary, when the servo chamber volume Vs is decreased, the reaction force chamber volume Vo is increased. A simulator fluid path HS is connected to the reaction chamber Ro. The reaction chamber Ro adjusts the amount of the braking fluid BF in the upper fluid unit YU.

A recessed portion Mx is provided at the first end portion Mv of the master piston PM. A master elastic body (for example, a compression spring) SM is provided between the recessed portion Mx and the first bottom portion Mu of the master cylinder CM. The master elastic body SM presses the master piston PM against the second bottom Mt of the master cylinder CM in the direction of the central axis Jm of the master cylinder CM. At the time of non-braking, the stepped portion My of the master piston PM and the second bottom portion Mt of the master cylinder CM are in contact with each other. The position of the master piston PM in this state is referred to as the "initial position of the master unit YM".

Between the two seals SL (eg, cup seals), the master cylinder CM is provided with a through hole Ac. The through hole Ac is connected to the master reservoir chamber Ru via the replenishment fluid passage HU. Further, a through hole Ap is provided in the vicinity of the first end portion Mv of the master piston PM. When the master piston PM is in the initial position, the master chamber Rm is communicated with the reservoir RV (particularly, the master reservoir chamber Ru) through the through holes Ac, Ap, and the replenishment fluid passage HU.

The master chamber Rm uses its internal pressure (“master cylinder hydraulic pressure”, also referred to as “master hydraulic pressure”) Pm to generate an urging force Fb (referred to as “regressive force”) in the receding direction Hb along the central axis Jm. It is given to the master piston PM. The servo chamber Rs applies an urging force Fa (referred to as "advance force") facing the retreat force Fb to the master piston PM by its internal pressure (that is, the introduced adjusting hydraulic pressure Pa). That is, in the master piston PM, the forward force Fa due to the hydraulic pressure Pv (= Pa) in the servo chamber Rs and the backward force Fb due to the hydraulic pressure (master hydraulic pressure) Pm in the master chamber Rm are in the direction of the central axis Jm. They oppose each other (face each other) and are statically balanced. A master hydraulic pressure sensor PQ is provided to detect the master hydraulic pressure Pm. For example, the master hydraulic pressure sensor PQ may be provided in the master cylinder fluid passage HM. Further, the master hydraulic pressure sensor PQ may be included in the lower fluid unit YL.

For example, the pressure receiving area of the first surface Ms of the brim portion Tm (that is, the pressure receiving area of the servo chamber Rs) rs is the pressure receiving area of the first end portion Mv of the master piston PM (that is, the pressure receiving area of the master chamber Rm) rm. It is set to be equal. In this case, the hydraulic pressure Pa (resulting in the servo hydraulic pressure Pv) introduced into the servo chamber Rs and the hydraulic pressure Pm in the master chamber Rm are the same in the steady state. At this time, the forward force Fa (= Pa × rs) and the backward force Fb (= Pm × rm (+ SM elastic force)) are in equilibrium.

[Pressure control unit YC]
The pressure adjusting unit YC adjusts the hydraulic pressures Pwf and Pwr of the front wheel, rear wheel cylinders CWf and CWr on demand. The pressure regulating unit YC includes an electric pump DC, a check valve GC, a pressure regulating valve UA, and a regulating hydraulic pressure sensor PA. The pressure regulating unit YC is an on-demand type (a unit that executes necessary functions when necessary without preparation in advance).

The electric pump DC is composed of a set of one electric motor MC and one fluid pump QC. In the electric pump DC, the electric motor MC and the fluid pump QC are fixed so that the electric motor MC and the fluid pump QC rotate together. The electric pump DC (particularly, the electric motor MC) is a power source for increasing the braking fluid pressure Pw during control braking. The electric motor MC is controlled by the controller ECU.

The suction port Qs of the fluid pump QC is connected to the reservoir RV (particularly, the pressure regulating reservoir chamber Rd) via the first reservoir fluid passage HV. A pressure regulating fluid passage HC is connected to the discharge port Qt of the fluid pump QC. By driving the electric pump DC (particularly, the fluid pump QC), the braking liquid BF is sucked from the first reservoir fluid passage HV through the suction port Qs and discharged from the discharge port Qt to the pressure regulating fluid passage HC. For example, a gear pump is adopted as the fluid pump QC.

A check valve GC (also referred to as a "check valve") is interposed in the pressure regulating fluid passage HC. By the check valve GC, the brake fluid BF can move from the first reservoir fluid path HV toward the pressure regulating fluid path HC, but moves from the pressure regulating fluid path HC toward the reservoir fluid path HV (that is,). , Backflow of brake fluid BF) is blocked. That is, the electric pump DC is rotated only in one direction. The end portion Bv of the pressure regulating fluid passage HC opposite to the discharge portion Qt is connected to the first reservoir fluid passage HV.

A pressure regulating valve UA is provided in the pressure regulating fluid path HC. The pressure regulating valve UA is a linear solenoid valve (also referred to as a "proportional valve" or "differential pressure valve") in which the valve opening amount (lift amount) is continuously controlled based on the energized state (for example, supply current). Is. The pressure regulating valve UA is controlled by the controller ECU based on the drive signal Ua. As the pressure regulating valve UA, a normally open solenoid valve is adopted.

The braking fluid BF is pumped from the first reservoir fluid passage HV through the suction port Qs of the fluid pump QC and discharged from the discharge port Qt. Then, the brake fluid BF passes through the check valve GC and the pressure regulating valve UA and is returned to the reservoir fluid path HV. In other words, the first reservoir fluid passage HV and the pressure regulating fluid passage HC form a recirculation path (a fluid path in which the flow of the braking fluid BF returns to the original flow again), and the check regurgitation is performed in this recirculation path. The valve GC and the pressure regulating valve UA are interposed in series.

When the electric pump DC is operating, the brake fluid BF recirculates in the order of "HV-> QC (Qs-> Qt)-> GC-> UA-> HV" as shown by the broken arrow (A). (That is, a "recirculation path" is formed). When the pressure regulating valve UA is in the fully open state (because it is a normally open type, it is not energized), the hydraulic pressure (adjusting hydraulic pressure) Pa in the pressure regulating fluid passage HC is approximately "0 (atmospheric pressure)". When the amount of electricity supplied to the pressure regulating valve UA is increased and the recirculation path is narrowed by the pressure regulating valve UA, the hydraulic pressure (adjusting hydraulic pressure) Pa between the fluid pump QC and the pressure regulating valve UA in the pressure regulating fluid path HC becomes "0". Is increased from. The pressure adjusting fluid passage HC is provided with an adjusting hydraulic pressure sensor PA so as to detect the adjusting hydraulic pressure Pa.

The pressure regulating fluid passage HC is branched into front wheels, rear wheel pressure regulating fluid passages HF, and HR at a portion Bc between the fluid pump QC and the pressure regulating valve UA. The front wheel pressure regulating fluid passage HF is connected to the servo chamber Rs of the master unit YM. Therefore, the regulated hydraulic pressure Pa adjusted by the pressure regulating valve UA is introduced (supplied) to the servo chamber Rs. Since the master cylinder CM is connected to the front wheel cylinder CWf via the lower fluid unit YL, the adjusting hydraulic pressure Pa is indirectly introduced into the front wheel cylinder CWf via the master cylinder CM. On the other hand, the rear wheel pressure regulating fluid passage HR is connected to the rear wheel wheel cylinder CWr via the lower fluid unit YL. Therefore, the adjusting hydraulic pressure Pa is directly introduced into the rear wheel hole cylinder CWr.

The pressure regulating unit YC is provided with a bypass fluid path HD connecting the reservoir RV and the servo chamber Rs in parallel with the pressure regulating fluid path HC. A check valve GD is interposed in the bypass fluid path HD. In the check valve GD, the flow of the braking fluid BF from the reservoir RV to the servo chamber Rs is allowed, but vice versa, the flow from the servo chamber Rs to the reservoir RV is blocked. When the braking operation member BP is suddenly operated, the master piston PM is moved in the forward direction Ha by the operation force of the driver, and the volume Vs of the servo chamber Rs is increased. In this case, the amount of liquid corresponding to the volume increase of the servo chamber Rs caused by the operation of the driver is supplied via the bypass fluid path HD and the check valve GD.

[Regenerative cooperation unit YK]
Coordinated control between friction braking and regenerative braking (referred to as "regenerative coordinating control") is achieved by the regenerative coordinating unit YK. For example, the regenerative coordination unit YK may form a state in which the braking operation member BP is operated but the braking fluid pressure Pw is not generated. The regeneration coordination unit YK is an input cylinder CN, an input piston PK, an input elastic body SN, a first on-off valve VA, a second on-off valve VB, a stroke simulator SS, a simulator hydraulic pressure sensor PS, and an input hydraulic pressure sensor PN. It is composed.

The input cylinder CN is a cylinder member having a bottom portion fixed to the master cylinder CM. The input piston PK is a piston member inserted inside the input cylinder CN. The input piston PK is mechanically connected to the braking operation member BP via a clevis (U-shaped link) so as to be interlocked with the braking operation member BP. The input piston PK is provided with a brim portion (flange) Tn. An input elastic body (for example, a compression spring) SN is provided between the mounting surface Ma of the input cylinder CN to the master cylinder CM and the brim Tn of the input piston PK. The input elastic body SN presses the brim portion Tn of the input piston PK against the bottom portion Mb of the input cylinder CN in the direction of the central axis Jm.

During non-braking, the stepped portion My of the master piston PM is in contact with the second bottom Mt of the master cylinder CM, and the brim Tn of the input piston PK is in contact with the bottom Mb of the input cylinder CN. During non-braking, the gap Ks between the master piston PM (particularly the end face Mq) and the input piston PK (particularly the end face Mg) is set to a predetermined distance ks (referred to as "initial gap") inside the input cylinder CN. There is. That is, when the pistons PM and PK are at the position of the most retracting direction Hb (referred to as the "initial position" of each piston) (that is, when not braking), the master piston PM and the input piston PK are separated by a predetermined distance ks. ing. Here, the predetermined distance ks corresponds to the maximum value of the regenerative amount Rg. When the regenerative cooperative control is executed, the gap (also referred to as “separation displacement”) Ks is controlled (adjusted) by the adjusting hydraulic pressure Pa.

When the braking operation member BP is stepped on from the state of "Ba = 0", the input piston PK is moved from its initial position to the forward direction Ha. At this time, if the adjustment hydraulic pressure Pa remains "0", the master piston PM remains in the initial position. Therefore, as the input piston PK advances, the gap Ks (the end face Mg of the input piston PK and the master piston PM) The distance from the end face Mq) gradually decreases. On the other hand, when the adjusting hydraulic pressure Pa is increased from "0", the master piston PM is moved from its initial position in the forward direction Ha. Therefore, the gap Ks can be adjusted independently of the braking operation amount Ba in the range of “0 ≦ Ks ≦ ks” by the adjusting hydraulic pressure Pa. That is, by adjusting the adjusting hydraulic pressure Pa, the gap Ks between the input piston PK and the master piston PM is adjusted, and regenerative cooperative control is achieved.

The input chamber Rn of the regenerative coordination unit YK and the reaction chamber Ro of the master unit YM are connected by the simulator fluid path HS. The simulator fluid path HS is provided with a first on-off valve VA. The first on-off valve VA is a normally closed solenoid valve having a first open position and a first closed position. The reservoir fluid path HT is connected to the portion Bs between the first on-off valve VA of the simulator fluid path HS and the reaction chamber Ro. The reservoir fluid passage HT is provided with a second on-off valve VB. The second on-off valve VB is a normally open solenoid valve having a second open position and a second closed position. The first and second on-off valves VA and VB are two-position solenoid valves (also referred to as "on / off valves") having an open position (communication state) and a closed position (blocking state). The first and second on-off valves VA and VB are controlled by the upper controller ECU based on the drive signals Va and Vb.

The simulator SS is connected to the simulator fluid path HS at a portion Bo between the first on-off valve VA and the reaction chamber Ro. In other words, the input chamber Rn of the regenerative coordination unit YK is connected to the simulator SS by the simulator fluid path HS. When the regenerative coordination control is executed, the first on-off valve VA is set to the open position and the second on-off valve VB is set to the closed position. Since the second on-off valve VB is in the closed position, the flow path to the reservoir RV is blocked in the reservoir fluid path HT. Therefore, the brake fluid BF is moved from the input chamber Rn of the input cylinder CN into the simulator SS. Since the elastic body Ds applies a force to prevent the inflow of the braking liquid BF to the piston Es of the simulator SS, an operating force Fp when the braking operating member BP is operated is generated.

The simulator fluid path HS is provided with an input chamber orifice OR (corresponding to an “orifice”). For example, the input chamber orifice OR is located at the connection portion between the input chamber Rn and the simulator fluid path HS (that is, the entrance / exit of the braking fluid BF of the input chamber Rn, and between the input chamber Rn and the first on-off valve VA). It will be provided. Under predetermined conditions, when the brake fluid BF passes through the orifice OR, it becomes a jet flow, and on the outlet side of the orifice OR (the side of the first on-off valve VA), compared to the inlet side of the orifice OR (the side of the input chamber Rn). The flow velocity increases and the pressure decreases. For example, the difference in hydraulic pressure before and after the orifice OR is proportional to the square of the flow rate of the braking fluid BF flowing through the orifice OR. Since the flow rate of the braking liquid BF is proportional to the operating speed dB of the braking operating member BP, the hydraulic pressure difference increases as the operating speed dB increases. As the orifice OR, in the flow of the braking fluid BF, when the operating speed dB is small (during normal operation), it does not become a resistance, but when the operating speed dB is large (during sudden operation), it becomes a resistance. ing. Details of the characteristics of the orifice OR will be described later.

The second reservoir fluid passage HT is connected to the reservoir RV (particularly, the pressure regulating reservoir chamber Rd). A part of the second reservoir fluid passage HT can be shared with the first reservoir fluid passage HV. However, it is desirable that the first reservoir fluid path HV and the second reservoir fluid path HT are separately connected to the reservoir RV. The fluid pump QC sucks the brake fluid BF from the reservoir RV via the first reservoir fluid passage HV, but at this time, air bubbles may be mixed in the first reservoir fluid passage HV. Therefore, the second reservoir fluid passage HT does not have an intersection with the first reservoir fluid passage HV and is separate from the first reservoir fluid passage HV so as to prevent air bubbles from being mixed into the input cylinder CN or the like. Is connected to the reservoir RV.

A simulator hydraulic pressure sensor PS is provided in the simulator fluid passage HS between the first on-off valve VA and the reaction chamber Ro so as to detect the hydraulic pressure (referred to as “simulator hydraulic pressure”) Ps in the simulator SS. Further, an input hydraulic pressure sensor PN is provided in the simulator fluid passage HS between the first on-off valve VA and the input chamber Rn so as to detect the hydraulic pressure (referred to as “input hydraulic pressure”) Pn in the input chamber Rn. Be done. The simulator hydraulic pressure sensor PS and the input hydraulic pressure sensor PN are one of the above-mentioned braking operation amount sensors BA. The detected hydraulic pressures Ps and Pn are input to the upper controller ECU as the braking operation amount Ba.

[Upper controller ECU]
The upper controller ECU controls the electric motor MC and the solenoid valves VA, VB, and UA based on the braking operation amount Ba, the operation signal St, and the adjusted hydraulic pressure (detection value) Pa. Specifically, the upper controller ECU calculates drive signals Va, Vb, and Ua for controlling various solenoid valves VA, VB, and UA. Similarly, the drive signal Mc for controlling the electric motor MC is calculated. Then, the solenoid valves VA, VB, UA, and the electric motor MC are driven based on the drive signals Va, Vb, Ua, and Mc.

The upper controller (electronic control unit) ECU is network-connected to the lower controller ECL and controllers of other systems (drive controller ECD, etc.) via the vehicle-mounted communication bus BS. The regenerative amount (target value) Rg is transmitted from the upper controller ECU to the drive controller ECD through the communication bus BS so as to execute the regenerative cooperative control.

[Lower fluid unit YL]
The lower fluid unit YL is a known fluid unit including a master hydraulic pressure sensor PQ, a plurality of solenoid valves, an electric pump, and a low pressure reservoir. The lower fluid unit YL is controlled by the lower controller ECL. Wheel speed Vw, yaw rate, steering angle, front-rear acceleration, lateral acceleration, etc. are input to the lower controller ECL. In the lower controller ECL, the vehicle body speed Vx is calculated based on the wheel speed Vw. Then, anti-skid control is executed so as to suppress excessive deceleration slip (for example, wheel lock) of the wheel WH based on the vehicle body speed Vx and the wheel speed Vw. Further, in the lower controller ECL, vehicle stabilization control (so-called ESC) for suppressing unstable behavior (excessive oversteer behavior, understeer behavior) of the vehicle is performed based on the yaw rate. That is, the braking fluid pressure Pw of each wheel WH is individually controlled by the lower fluid unit YL. The calculated vehicle body speed Vx is input to the upper controller ECU through the communication bus BS.

[Operation of braking control device SC]
When the vehicle start switch (for example, the ignition switch) is turned on, the first on-off valve VA is set to the open position and the second on-off valve VB is set to the closed position. Therefore, while the vehicle is traveling, the input chamber Rn of the regenerative coordination unit YK and the reaction chamber Ro of the master unit YM are in communication with each other via the simulator fluid path HS and the first on-off valve VA. On the other hand, since the second on-off valve VB is in the closed position, the input chamber Rn and the reaction force chamber Ro are cut off from the reservoir RV.

During non-braking (for example, when the braking operation member BP is not operated), the pressure regulating valve UA and the electric motor MC are not energized. At this time, the pistons PM and PN are pressed to their respective initial positions by the elastic bodies SM and SN, and the hydraulic chamber Rm of the master cylinder CM and the liquid reservoir Ru of the reservoir RV are in a communicating state, and the master hydraulic pressure Pm. Is "0 (atmospheric pressure)".

When the braking operation member BP is operated (particularly at the start of control braking), the input piston PK is moved in the forward direction Ha. At this time, the amount of the braking liquid BF flowing out of the input chamber Rn flows into the simulator SS, and the operating force Fp of the braking operation member BP is formed.

When the vehicle deceleration is sufficient with the regenerative braking force generated by the generator GN, the state of "Pa = 0" is maintained. By operating the braking operation member BP, the input piston PK is moved from its initial position in the forward direction Ha, but at this time, the master piston PM is not moved because the adjustment hydraulic pressure Pa remains “0”. .. Therefore, as the input piston PK advances, the gap Ks (distance between the end face Mg of the input piston PK and the end face Mq of the master piston PM) gradually decreases.

When the vehicle deceleration is insufficient with the regenerative braking force by the generator GN, the pressure adjusting unit YC is controlled by the controller ECU, and the adjusting hydraulic pressure Pa is adjusted on demand. The adjusting hydraulic pressure Pa is applied to the servo chambers Rs through the front wheel pressure adjusting fluid passage HF. When the force (forward force) Fa in the forward direction Ha generated by the hydraulic pressure (called "servo hydraulic pressure") Pv (= Pa) in the servo chamber Rs becomes larger than the set load of the master elastic body SM, the master piston PM Is moved along the central axis Jm of the master cylinder CM. By this movement in the forward direction Ha, the master chamber Rm is cut off from the reservoir RV. Further, when the adjusting hydraulic pressure Pa is increased, the braking fluid BF is pressure-fed from the master cylinder CM toward the front wheel wheel cylinder CWf at the master hydraulic pressure Pm. A force (retracting force) Fb in the retreating direction Hb acts on the master piston PM due to the master hydraulic pressure Pm. The servo chamber Rs generates a force (forward force) Fa in the forward direction Ha by the adjusting hydraulic pressure Pa so as to oppose (oppose) the backward force Fb. The master hydraulic pressure Pm is increased or decreased according to the increase or decrease of the adjusted hydraulic pressure Pa. As the adjustment hydraulic pressure Pa increases, the master piston PM is moved from the initial position to the forward direction Ha, but the clearance Ks becomes the braking operation amount Ba in the range of "0≤Ks≤ks" due to the adjustment hydraulic pressure Pa. Can be adjusted independently. That is, the regenerative cooperative control is executed by adjusting the gap Ks with the adjusting hydraulic pressure Pa. The adjusting hydraulic pressure Pa is directly applied to the rear wheel cylinder CWr through the rear wheel pressure regulating fluid passage HR and the lower fluid unit YL.

When the braking operation member BP is returned, the adjusting hydraulic pressure Pa is reduced. Then, when the servo hydraulic pressure Pv (= Pa) becomes smaller than the master chamber hydraulic pressure Pm (= Pwf), the master piston PM is moved in the backward direction Hb. When the braking operation member BP is put into a non-operation state, the position (initial position) where the master piston PM (particularly, the stepped portion My) comes into contact with the second bottom Mt of the master cylinder CM due to the elastic force of the compression spring SM. Is returned to.

During manual braking (power failure, etc.), the first and second on-off valves VA and VB are not energized. Therefore, the first on-off valve VA is in the closed position and the second on-off valve VB is in the open position. The closed position of the first on-off valve VA puts the input chamber Rn in a fluid-locked state (sealed state) so that the input piston PK and the master piston PM cannot move relative to each other. Further, depending on the open position of the second on-off valve VB, the reaction force chamber Ro is connected to the reservoir RV through the second reservoir fluid passage HT. Therefore, the volume Vo of the reaction chamber Ro is reduced by the movement of the forward direction Ha of the master piston PM, but the liquid volume accompanying the volume reduction is discharged toward the reservoir RV. The input piston PK and the master piston PM are integrally moved (that is, "Ks = 0") in conjunction with the operation of the braking operation member BP, and the brake fluid BF is transferred from the master chamber Rm to the front wheel cylinder CWf. It is pumped.

<Action of orifice OR>
The operation of the input chamber orifice OR provided in the simulator fluid path HS will be described with reference to the characteristic diagram of FIG. The orifice characteristic Co is when the first on-off valve VA and the second on-off valve VB are both in the open position in the braking control device SC (that is, the input chamber Rn and the atmospheric pressure reservoir RV are in a communicating state). When the operation speed dB of the braking operation member BP (that is, the flow rate of the braking liquid BF passing through the orifice OR) is changed, the internal pressure of the input chamber Rn (that is, before and after the orifice OR) is changed. Hydraulic pressure difference) is plotted. In the characteristic Co of the orifice OR, the internal pressure (hydraulic pressure difference, fluid resistance of the orifice OR) of the input chamber Rn increases substantially in proportion to the square of the braking operation speed dB (= flow rate).

In the input chamber orifice OR, when the braking operation speed dB is equal to or less than the first predetermined value da, there is no resistance to the flow of the braking liquid BF. As a result, the orifice OR does not affect the operating characteristics of the braking operating member BP. That is, the internal pressure generated at "dB = da" is a value pa, which is approximately "0 (atmospheric pressure)". For example, the first predetermined value da is the maximum value of the operation speed dB in a normal braking operation. In other words, the braking operation member BP is usually operated at the first predetermined value da or less, and in this situation, the influence of the orifice OR can be ignored.

On the other hand, in the input chamber orifice OR, when the braking operation speed dB is equal to or higher than the second predetermined value db, it becomes a resistance to the flow of the braking liquid BF. Here, the second predetermined value db is a value extremely larger than the first predetermined value da, and corresponds to a sudden operation of the braking operation member BP. The internal pressure generated at "dB = db" is a value pb, and the internal pressure pushes the master piston PM in the forward direction Ha. That is, during sudden braking, even if the first on-off valve VA is in the open position, the orifice OR makes it difficult for the braking fluid BF to be discharged from the input cylinder CN (that is, the input chamber Rn), and the input cylinder CN is in a confined state. Is formed. That is, the input cylinder CN is brought into a state close to the fluid lock (completely contained state) due to the closed position of the first on-off valve VA. Therefore, the operating force Fp by the driver is transmitted to the master piston PM, so that the boost response of the master cylinder hydraulic pressure Pm is improved.

The characteristic Co of the orifice OR (particularly, the cross-sectional area of the opening) can be set experimentally. Further, since a standard orifice whose dimensions and flow coefficient are standardized is defined by an industrial standard or the like, this may be used. In any case, as the input chamber orifice OR, one that can obtain the effect of assisting the pressure increase of the master cylinder hydraulic pressure Pm at a desired operating speed dB can be adopted.

The valve seat of the first on-off valve VA can be used as the input chamber orifice OR. In the first on-off valve VA, the flow of the braking fluid BF is regulated by the valve body and the valve seat, but the valve seat hole of the first on-off valve VA can have the function of an orifice OR. This can simplify the configuration of the braking control device SC.

<Pressure control processing>
The process of pressure regulation control including the regenerative cooperative control will be described with reference to the control flow diagram of FIG. "Pressure adjustment control" is drive control of the electric motor MC and the pressure adjustment valve UA for adjusting the adjustment hydraulic pressure Pa. The control algorithm is programmed in the upper controller ECU.

In step S110, the braking control device SC is initialized. In step S110, the initial diagnosis of each component is executed. In step S120, the normally closed type first on-off valve VA and the normally open type second on-off valve VB are energized. That is, when the start switch of the device is turned on, the first on-off valve VA is set to the open position and the second on-off valve VB is set to the closed position. The on / off states of the first and second on-off valves VA and VB are not switched for each braking operation, but the first and second on-off valves VA and VB are always energized while the vehicle is running. Will be. This is advantageous in terms of operating noise and can stabilize the characteristics of the simulator SS.

In step S130, the braking operation amount Ba, the operation signal St, the adjustment hydraulic pressure (detection value) Pa, and the vehicle body speed Vx are read. The operation amount Ba is detected by the operation amount sensor BA (operation displacement sensor SP, input hydraulic pressure sensor PN, simulator hydraulic pressure sensor PS, etc.). The operation signal St is detected by the operation switch ST. The adjusting hydraulic pressure Pa is detected by the adjusting hydraulic pressure sensor PA provided in the pressure adjusting fluid passage HC. The vehicle body speed Vx is acquired from the lower controller ECL via the communication bus BS. As for the vehicle body speed Vx, the wheel speed Vw may be input to the upper controller ECU and calculated by the upper controller ECU based on the wheel speed Vw.

In step S140, "whether braking is in progress or not" is determined based on at least one of the braking operation amount Ba and the braking operation signal St. For example, when the manipulated variable Ba is larger than the predetermined value bo, step S140 is affirmed and the process proceeds to step S150. On the other hand, when the operation amount Ba is equal to or less than the predetermined value bo, step S140 is denied and the process is returned to step S130. Here, the predetermined value bo is a preset constant corresponding to the play of the braking operation member BP. If the operation signal St is on, the process proceeds to step S150, and if the operation signal St is off, the process returns to step S130.

In step S150, as shown in the block X150, the required braking force Fd is calculated based on the operation amount Ba. The required braking force Fd is a target value of the total braking force F acting on the vehicle, and is a braking force obtained by combining "friction braking force Fm by the braking control device SC" and "regenerative braking force Fg by the generator GN". The required braking force Fd is determined to be "0" when the operation amount Ba is in the range of "0" to the predetermined value bo according to the calculation map Zfd, and when the operation amount Ba is equal to or more than the predetermined value bo, the operation amount Ba increases. Therefore, it is calculated so as to monotonically increase from "0".

In step S160, as shown in the block X160, the maximum value (referred to as “maximum regenerative force”) Fx of the regenerative braking force is calculated based on the vehicle body speed Vx and the calculation map Zfx. The amount of regeneration of the generator GN is limited by the rating of the power transistor (IGBT or the like) of the drive controller ECD and the charge acceptability of the battery. For example, the regenerative amount of the generator GN is controlled to a predetermined electric power (electrical energy per unit time). Since the electric power (power) is constant, the regenerative torque around the wheel shaft by the generator GN is inversely proportional to the rotation speed of the wheel WH (that is, the vehicle body speed Vx). Further, when the rotation speed Ng of the generator GN decreases, the amount of regeneration decreases. Further, an upper limit is set for the amount of regeneration.

From the above, in the calculation map Zfx for the maximum regenerative force Fx, in the range where the vehicle body speed Vx is "0" or more and less than the first predetermined speed vo, the maximum regenerative force Fx increases as the vehicle body speed Vx increases. Is set. Further, in the range where the vehicle body speed Vx is equal to or higher than the first predetermined speed vo and less than the second predetermined speed vp, the maximum regenerative force Fx is determined to be the upper limit value fx. When the vehicle body speed Vx is equal to or higher than the second predetermined speed vp, the maximum regenerative force Fx is set to decrease as the vehicle body speed Vx increases. For example, in the reduction characteristic of the maximum regenerative force Fx (characteristic of "Vx ≧ vp"), the relationship between the vehicle body speed Vx and the maximum regenerative force Fx is represented by a hyperbola (that is, the regenerative power is constant). Here, the predetermined values vo and vp are preset constants. In the calculation map Zfx, the rotation speed Ng of the generator GN can be adopted instead of the vehicle body speed Vx.

In step S170, "whether or not the required braking force Fd is equal to or less than the maximum regenerative force Fx" is determined based on the required braking force Fd and the maximum regenerative force Fx. That is, it is determined whether or not the braking force Fd required by the driver can be achieved only by the regenerative braking force Fg. If “Fd ≦ Fx” and step S170 is affirmed, the process proceeds to step S180. On the other hand, if "Fd> Fx" and step S170 is denied, the process proceeds to step S190.

In step S180, the required braking force Fd is determined to be the regenerative braking force Fg. Further, in step S180, the target friction braking force Fm is calculated to be "0". The target friction braking force Fm is a target value of the braking force to be achieved by friction braking. In this case, friction braking is not adopted for vehicle deceleration, and the required braking force Fd is achieved only by regenerative braking. In step S190, the regenerative braking force Fg is determined to be the maximum regenerative force Fx. Further, in step S190, the target friction braking force Fm is calculated based on the required braking force Fd and the maximum regenerative force Fx. Specifically, the target friction braking force Fm is determined by subtracting the maximum regenerative force Fx from the required braking force Fd. That is, in the required braking force Fd, the shortage of the regenerative braking force Fg (= Fx) is supplemented by the target friction braking force Fm.

In step S200, the regenerative amount Rg is calculated based on the regenerative braking force Fg. The regenerative amount Rg is a target value of the regenerative amount of the generator GN. The regenerative amount Rg is transmitted from the braking controller ECU to the drive controller ECD via the communication bus BS. In step S210, the target hydraulic pressure Pt is calculated based on the target value Fm of the friction braking force. The target hydraulic pressure Pt is a target value of the adjusted hydraulic pressure Pa. In step S210, the target friction braking force Fm is converted into hydraulic pressure, and the target hydraulic pressure Pt is determined.

In step S220, it is determined whether or not the rapid operation process is necessary, and if necessary, the rapid operation process is executed. The rapid operation process is a process for improving the boost response of the braking fluid pressure Pw. The details of the quick operation process will be described later.

In step S230, the electric motor MC is driven, and the recirculation of the braking fluid BF including the fluid pump QC is formed. The electric motor MC (electric pump DC) is driven (rotated) even when "Pt = 0" during braking in order to ensure boost response. In step S240, the pressure regulating valve UA is servo-controlled so that the adjusted hydraulic pressure Pa approaches the target hydraulic pressure Pt based on the target hydraulic pressure Pt and the adjusted hydraulic pressure (detected value of the liquid conditioning pressure sensor PA) Pa. To. In the servo control, feedback control is performed so that the actual value Pa matches the target value Pt.

<Rapid operation processing>
The processing at the time of sudden operation will be described with reference to the control flow diagram of FIG. The "rapid operation process" improves the boost response of the braking fluid pressure Pw when the braking operation member BP is suddenly operated (that is, during sudden braking) by the driver. When the process is not executed, the driver's operation is a "brake-by-wire" configuration separated from the braking hydraulic pressure Pw, but during sudden braking, the input chamber orifice OR allows the input chamber Rn to operate. A containment state is formed, and the driver's operating force (operating power) is used to improve the boost response.

In step S410, the operation speed dB is calculated based on the operation amount Ba. Specifically, the operation speed dB is calculated by differentiating the operation amount Ba with respect to time. Here, the operation amount Ba is a state quantity indicating the degree of operation of the braking operation member BP, and is based on at least one of the operation displacement Sp, the operation force Fp, the input hydraulic pressure Pn, and the simulator hydraulic pressure Ps. Will be decided. Further, it is preferable that the operation displacement Sp is adopted as the operation amount Ba, and the operation speed dS (differential value of the operation displacement Sp) is calculated as the operation speed dB. The operation of the braking operation member BP is dynamically propagated in the order of "Sp → Pn → Ps", but the operation displacement Sp is a state quantity closest to the braking operation member BP and is detected early in time. Based on the state quantity to be done.

In step S420, "whether or not the operation of the braking operation member BP is a sudden operation" is determined based on the operation speed dB. For example, the determination of sudden operation is affirmed when the following two conditions (A1 and A2) are both satisfied.
Condition A1: The operation speed dB is equal to or higher than the first predetermined speed dx. The first predetermined speed dx is a preset constant (predetermined value). For example, it can be set as "dx = db". Here, the value db is a second predetermined value (see FIG. 2).
Condition A2: The operation amount Ba is a predetermined amount bx or more. The predetermined amount bx is a preset constant (predetermined value).
When "dB ≧ dB (= db) and Ba ≧ bx", step S420 is affirmed, and the process proceeds to step S430. On the other hand, "dB <dx or Ba <bx", step S420 is denied, and processing is returned to step S410.

In step S430, the elapsed time Tz is calculated. The elapsed time Tz is the elapsed time from the time when the determination in step S420 is affirmed for the first time in a series of braking operations (that is, operations from the start of braking to the end of braking). That is, in the calculation cycle in which the sudden operation is determined for the first time, the timer is operated and the elapsed time Tz is accumulated.

In step S440, it is determined whether or not the condition for ending the sudden operation process is satisfied. When at least one of the following three conditions (B1 to B3) is satisfied, the rapid operation process is terminated.
Condition B1: The elapsed time Tz is equal to or longer than the predetermined time tz. The predetermined time tz is a preset constant (predetermined value).
Condition B2: Sudden operation was weakened. The state is "the operation speed dB is less than the second predetermined speed dy". Here, the second predetermined speed dy is a preset constant (predetermined value) smaller than the first predetermined speed dx (that is, "dy <dx").
Condition B3: The braking operation is completed. That is, "Ba = 0" was achieved.

If step S440 is denied, the process proceeds to step S450 and the rapid operation process is executed. In the quick operation process, the second on-off valve VB is set to the open position in step S450. In the situation where the rapid operation process is performed, the orifice OR causes the input chamber Rn to be in a confined state (that is, the input chamber Rn is fluid-locked). Therefore, the master piston PM is moved in the forward direction Ha by the input piston PK connected to the braking operation member BP. When the master piston PM is moved in the forward direction Ha, the volume Vo of the reaction chamber Ro is reduced. When the second on-off valve VB is in the closed position, the braking fluid BF of the reaction chamber Ro flows into the simulator SS. The simulator SS is provided with an elastic body Ds for generating an operating force Fp, and a simulator orifice Os is provided at the entrance thereof for improving the operating characteristics. The elastic body Ds and the simulator orifice Os become resistance to the inflow of the braking fluid BF. In order to avoid this resistance, the second on-off valve VB is opened, and the brake fluid BF in the reaction chamber Ro is moved to the reservoir RV without resistance. Further, when the master piston PM is moved in the forward direction Ha, the volume Vs of the servo chamber Rs is increased. At this time, the servo chamber Rs needs to suck the brake fluid BF, but since the bypass fluid path HD is provided so that the fluid pump QC can be bypassed, the bypass fluid path HD and the check valve GD Brake fluid BF can be sucked in without resistance.

If step S440 is affirmed, the process proceeds to step S460, the rapid operation process is terminated, and the normal state is restored. At this time, since the flow rate passing through the orifice OR is reduced, the state of the fluid lock of the input chamber Rn is eliminated. In step S460, the second on-off valve VB is closed, the hydraulic chambers Rn and Ro and the reservoir RV are brought into a non-communication state, and are returned to a normal state.

At the time of sudden operation (for example, “dB ≧ dB (= db)”), the operating force Fp of the braking operation member BP operated by the driver due to the fluid resistance of the input chamber orifice OR is transmitted through the input chamber Rn. , Is transmitted to the master piston PM. Under normal conditions (that is, other than during sudden operation and in the state of "dB≤da"), the resistance of the orifice OR is negligibly small, and the master piston PM is driven only by the adjusting hydraulic pressure Pa in the servo chamber Rs. Will be done. However, at the time of sudden operation, the master piston PM is pressed in the forward direction Ha by the adjusting hydraulic pressure Pa and the operating force Fp of the driver. Therefore, the responsiveness is improved when the hydraulic pressure Pm of the master cylinder is increased.

Since the pressure regulating unit YC is an on-demand type, the electric pump DC is stopped during non-braking. Therefore, when the braking operation member BP is suddenly operated, the increase in the adjusting hydraulic pressure Pa cannot catch up with the increase in the operating force Fp (the rise of the adjusting hydraulic pressure Pa is relative to the rise of the operating force Fp). A state of being delayed) may occur. When the braking fluid BF is supplied from the reservoir RV to the servo chamber Rs through the fluid pump QC, the fluid pump QC acts as a fluid resistance. In order to avoid this, the bypass fluid path HD is provided in parallel with the pressure regulating fluid path HC including the pressure regulating valve UA. When the rise of the adjusting hydraulic pressure Pa is delayed, the servo chamber Rs can suck the braking fluid BF from the bypass fluid path HD, so that the pressure increasing response of the master hydraulic pressure Pm can be ensured. The bypass fluid path HD is provided with a check valve GD so as to prevent the braking fluid BF from moving from the servo chamber Rs to the reservoir RV.

The simulator SS is provided with elastic bodies Ds so as to generate an operating force Fp. In addition, the simulator SS is provided with a simulator orifice Os so as to improve the operating characteristics by the damping effect. When the second on-off valve VB is in the closed position, the master piston PM is moved in the forward direction Ha, and the volume Vo of the reaction chamber Ro is reduced, the brake fluid BF is absorbed by the simulator SS. It is necessary to be done. However, since the simulator SS is provided with the above-mentioned elastic body Ds and orifice Os, these serve as the inflow resistance of the braking fluid BF into the simulator SS. In the rapid operation process, the second on-off valve VB is set to the open position, so that the braking fluid BF for the volume reduction of the reaction chamber Ro reaches the reservoir RV via the simulator fluid path HS and the reservoir fluid path HT. Will be returned. Therefore, since the braking fluid BF in the reaction chamber Ro is moved without resistance, the responsiveness of the master hydraulic pressure Pm can be effectively achieved.

<Second Embodiment of Braking Control Device SC>
A second embodiment of the braking control device SC will be described with reference to the overall configuration diagram of FIG. The braking control device SC according to the second embodiment is also configured to include a master unit YM, a regenerative coordination unit YK, a pressure adjusting unit YC, and a controller ECU. The master unit YM and the regenerative cooperation unit YK are the same as those in the first embodiment. In the first embodiment, the pressure regulating unit YC is composed of one pressure regulating valve UA, and the same hydraulic pressure (adjusting hydraulic pressure) Pa is supplied to the servo chamber Rs and the rear wheel wheel cylinder CWr. Instead of this, in the second embodiment, the pressure regulating unit YC is configured to include two pressure regulating valves UB and UC, and the supply hydraulic pressure Pc to the servo chamber Rs and the rear wheel wheel cylinder by the controller ECU. It is controlled independently and individually from the supply hydraulic pressure Pb to the CWr. Hereinafter, the points different from the first embodiment will be mainly described. In the second embodiment, the front wheel WHf is provided with a generator GN.

Similar to the first embodiment, in the second embodiment, the components, arithmetic processing, signals, characteristics, and values designated with the same symbols have the same function. The subscripts "i" to "l" at the end of the symbol are comprehensive symbols indicating which wheel is related, "i" is the right front wheel, "j" is the left front wheel, and "k" is the right rear wheel. "L" indicates the left rear wheel. When the subscripts "i" to "l" are omitted, each symbol represents a general term for each of the four wheels. Further, the subscripts "f" and "r" at the end of the symbol are comprehensive symbols indicating which of the front and rear wheels is related to the two fluid paths (movement paths of the braking fluid BF), and are "f". "" Indicates a front wheel system, and "r" indicates a rear wheel system. When the subscripts "f" and "r" are omitted, it represents a general term for the two systems. In each fluid path, the "upstream side (or upper part)" is the side closer to the reservoir RV, and the "downstream side (or lower part)" is the side closer to the wheel cylinder CW.

[Other examples of pressure control unit YC]
The pressure regulating unit YC includes an electric pump DC, a check valve GC, first and second pressure regulating valves UB and UC, and first and second adjusting hydraulic pressure sensors PB and PC. The hydraulic pressure Pwf of the front wheel cylinder CWf and the hydraulic pressure Pwr of the rear wheel wheel cylinder CWr are independently and individually adjusted by the pressure adjusting unit YC. Specifically, the braking hydraulic pressure Pwf of the front wheel WHf provided with the generator GN is adjusted to be equal to or lower than the braking hydraulic pressure Pwr of the rear wheel WHr not equipped with the generator GN.

Similarly to the above, the electric pump DC is composed of one electric motor MC and one fluid pump QC, and they rotate together. In the fluid pump QC, the suction port Qs is connected to the first reservoir fluid path HV, and the discharge port Qt is connected to one end of the pressure regulating fluid path HC. A check valve GC is provided in the pressure regulating fluid path HC. The other end Bv of the pressure regulating fluid path HC is connected to the reservoir fluid path HV.

In the pressure regulating fluid path HC, two pressure regulating valves UB and UC are provided in series. Specifically, the pressure regulating fluid path HC is provided with a first pressure regulating valve UB. Then, the second pressure regulating valve UC is arranged between the first pressure regulating valve UB and the site Bv. Similar to the pressure regulating valve UA, the first and second pressure regulating valves UB and UC are linear solenoid valves whose valve opening amount (lift amount) is continuously controlled based on the energized state (for example, supply current). Proportional valve, differential pressure valve). The first and second pressure regulating valves UB and UC are controlled by the controller ECU based on the drive signals Ub and Uc. As the first and second pressure regulating valves UB and UC, a normally open solenoid valve is adopted.

When the electric pump DC is driven, the recirculation of the braking fluid BF of "HV-> QC (Qs-> Qt)-> GC-> UB-> UC-> HV" is formed. When the first and second pressure regulating valves UB and UC are in the fully open state (these are normally open types, so that they are not energized), the hydraulic pressures (adjusting hydraulic pressures) Pb and Pc in the pressure regulating fluid passage HC are Both are approximately "0 (atmospheric pressure)". When the amount of electricity supplied to the first pressure regulating valve UB is increased and the recirculation is throttled by the pressure regulating valve UB, the hydraulic pressure between the fluid pump QC and the first pressure regulating valve UB in the pressure regulating fluid passage HC (first adjusting hydraulic pressure). Pb is increased from "0". Further, when the amount of electricity supplied to the second pressure regulating valve UC is increased and the recirculation is throttled by the pressure regulating valve UC, the hydraulic pressure between the first pressure regulating valve UB and the second pressure regulating valve UC in the pressure regulating fluid passage HC (second). Adjusting fluid pressure) Pc is increased from "0".

Since the first and second pressure regulating valves UB and UC are arranged in series with the pressure regulating fluid path HC, the second adjusting hydraulic pressure Pc adjusted by the second pressure regulating valve UC is the first adjusting hydraulic pressure Pb. It is as follows. In other words, the second pressure regulating valve UC adjusts the second adjusting hydraulic pressure Pc to increase from "0 (atmospheric pressure)", and the first pressure regulating valve UB causes the first adjusting hydraulic pressure Pb to increase from "0 (atmospheric pressure)" to the second. It is adjusted to increase from the adjusted hydraulic pressure Pc. In the pressure adjusting unit YC, the first and second adjusting hydraulic pressure sensors PB and PC are provided in the pressure adjusting fluid path HC so as to detect the first and second adjusting hydraulic pressures Pb and Pc.

The pressure regulating fluid passage HC is branched into the rear wheel pressure regulating fluid passage HR at the portion Bh between the fluid pump QC and the first pressure regulating valve UB. The rear wheel pressure regulating fluid passage HR is connected to the rear wheel cylinder CWr via the lower fluid unit YL. Therefore, the first adjusting hydraulic pressure Pb is directly introduced (supplied) to the rear wheel hole cylinder CWr. Further, the pressure regulating fluid passage HC is branched into the front wheel pressure regulating fluid passage HF at the portion Bg between the first pressure regulating valve UB and the second pressure regulating valve UC. The front wheel pressure regulating fluid passage HF is connected to the servo chamber Rs. Therefore, the second adjusting hydraulic pressure Pc is introduced (supplied) into the servo chamber Rs. Since the master cylinder CM is connected to the front wheel cylinder CWf via the lower fluid unit YL, the second adjusting hydraulic pressure Pc is indirectly introduced into the front wheel cylinder CWf via the master cylinder CM. Cylinder.

Similar to the first embodiment, in order to improve the boost response during sudden braking, the pressure regulating unit YC has a bypass fluid connecting the reservoir RV and the servo chamber Rs in parallel with the pressure regulating fluid path HC. Road HD is provided. A check valve GD is interposed in the bypass fluid path HD. In the check valve GD, the flow of the braking fluid BF from the reservoir RV to the servo chamber Rs is allowed, but the flow from the servo chamber Rs to the reservoir RV is blocked.

In the second embodiment, the first adjusted hydraulic pressure Pb and the second adjusted hydraulic pressure Pc are adjusted independently and separately within the range of “Pb ≧ Pc”. As a result, the regenerative cooperative control is executed in consideration of the front-rear distribution of the braking force, so that the deceleration and stability of the vehicle can be ensured and the regenerative energy can be maximized.

For example, when the required braking force Fd according to the operation amount Ba is equal to or less than the regenerative braking force (maximum regenerative force) Fx that can be generated by the generator GN, it is controlled to "Pb = Pc = 0" and the friction braking force. Fm is not generated. Here, the required braking force Fd is a braking force for the entire vehicle, and is increased as the operation amount Ba increases. When the operation amount Ba is increased and the regenerative braking force Fg exceeds the maximum regenerative force Fx (see block X160 in FIG. 3), the required braking force Fd cannot be achieved with the regenerative braking force Fg. In this case, the friction braking force Fmr of the rear wheel WHr is increased by the first adjusting hydraulic pressure Pb corresponding to the shortage of the regenerative braking force Fg with respect to the required braking force Fd (that is, "Fd-Fx"). At this time, "Pc = 0" remains, only the regenerative braking force is applied to the front wheel WHf, and the friction braking force Fmf is not generated. The ratio of the front wheel braking force to the total braking force (front-rear distribution ratio) Hf is gradually decreased from 100% when the friction braking force Fmr of the rear wheel WHr is sequentially increased. When the operation amount Ba is further increased and the above-mentioned distribution ratio Hf reaches a preset predetermined ratio (constant) hf, the second adjustment hydraulic pressure Pc starts to increase from "0". As the second adjusting hydraulic pressure Pc increases, the friction braking force Fmf of the front wheel WHf increases. Therefore, the front-rear distribution ratio Hf is maintained at a desired value hf while the regenerative braking force Fg maintains its maximum value Fx.

As described above, the front wheel hydraulic pressure Pwf and the rear wheel hydraulic pressure Pwr are individually adjusted by the first and second adjustment hydraulic pressures Pb and Pc. Specifically, as the operation amount Ba increases, "only the regenerative braking force Fg of the front wheel WHf due to the generator GN" → "(regenerative braking force Fg of the front wheel WHf) + (friction of the rear wheel WHr due to the first adjusted hydraulic pressure Pb)". Braking force Fmr) "→" (Regenerative braking force Fg of front wheel WHf) + (Friction braking force Fmf of front wheel WHf by second adjusted hydraulic pressure Pc) + (Friction braking force Fmr of rear wheel WHr) " The generation state of is changed. As a result, sufficient energy that can be regenerated is secured, and the front-rear distribution of the braking force is made appropriate, so that the deceleration and stability of the vehicle can be ensured.

The second embodiment also has the same effect as the first embodiment. That is, at the time of sudden operation, the orifice OR acts as a resistance in the movement of the braking liquid BF, so that the input chamber Rn is put into the fluid lock state. As a result, in addition to the second adjusted hydraulic pressure Pc, the master piston PM is driven by the operating force Fp by the driver, and the boost responsiveness of the master hydraulic pressure Pm is improved. Further, when the increase of the second adjusting hydraulic pressure Pc is delayed with respect to the increase of the operating force Fp, the braking liquid BF to the servo chamber Rs is supplied from the reservoir RV via the bypass fluid path HD. Since the fluid resistance is low in the movement of the braking fluid BF, the boost response can be effectively improved. Further, the simulator SS includes resistance elements such as an elastic body Ds and an orifice Os, but at the time of sudden operation, the second on-off valve VB is opened and the braking fluid BF from the reaction chamber Ro is passed through the fluid path. It is moved to the reservoir RV via HS and HT. The influence of the resistance element can be avoided and the boost response can be efficiently improved.

<Third Embodiment of the braking control device SC>
Next, a third embodiment of the braking control device SC will be described. In the second embodiment, in the vehicle provided with the generator GN on the front wheel WHf, the first adjusting hydraulic pressure Pb is introduced into the rear wheel cylinder CWr, and the second adjusting hydraulic pressure Pc is supplied to the servo chamber Rs. The third embodiment is applied to a vehicle having a generator GN on the rear wheel WHr, the first adjusting hydraulic pressure Pb is supplied to the servo chamber Rs, and the second adjusting hydraulic pressure Pc is supplied to the rear wheel cylinder CWr. .. That is, in FIG. 5, the front wheel pressure regulating fluid passage HF is connected to the portion Bh, and the rear wheel pressure regulating fluid passage HR is connected to the portion Bg.

The rear wheel hydraulic pressure Pwr and the front wheel hydraulic pressure Pwf are individually adjusted by the first and second adjustment hydraulic pressures Pb and Pc. Specifically, as the operation amount Ba increases, "only the regenerative braking force Fg of the rear wheel WHr by the generator GN" → "(friction braking force Fmf of the front wheel WHf by the first adjusting hydraulic pressure Pb) + (rear wheel WHr) Regenerative braking force Fg) ”→“ (Friction braking force Fmf of front wheel WHf due to second adjusted hydraulic pressure Pc) + (Regenerative braking force Fg of rear wheel WHr) + (Friction braking force Fmr of rear wheel WHr) ” The state of generation of braking force is changed. As a result, sufficient energy that can be regenerated is secured, and the front-rear distribution of the braking force is made appropriate, so that the deceleration and stability of the vehicle can be ensured. Further, in the responsiveness of the master hydraulic pressure Pm, the boost responsiveness of the master cylinder hydraulic pressure Pm (resulting in the braking hydraulic pressure Pw) is improved by driving the orifice OR and the second on-off valve VB.

<Action / effect>
The operation and effect of the braking control device SC according to the present invention will be summarized.
The braking control device SC pumps the brake fluid BF to the wheel cylinder CW provided on the wheel WH according to the operation amount Ba of the braking operation member BP, and as a result, braking torque is generated on the wheel WH. The braking control device SC is composed of a simulator SS, a master unit YM, a pressure regulating unit YC, and a regenerative coordination unit YK.

The simulator SS applies an operating force Fp corresponding to the operation of the braking operation member BP to the braking operation member BP. The master unit YM is composed of a master cylinder CM and a master piston PM. The master unit YM has a "master chamber Rm connected to the wheel cylinder CW" and a servo chamber that applies a forward force Fa facing the backward force Fb applied to the master piston PM by the master chamber Rm to the master piston PM. "Rs" is provided. The pressure regulating unit YC is composed of an electric pump DC that sucks the braking fluid BF from the reservoir RV, and solenoid valves UA, UB, and UC. In the pressure regulating unit YC, the braking fluid BF discharged by the electric pump DC is adjusted to the adjusting hydraulic pressures Pa, Pb, Pc by the solenoid valves UA, UB, UC, and the adjusting hydraulic pressures Pa, Pb, Pc are the servo chambers Rs. Will be introduced to. The regenerative coordination unit YK is composed of an input piston PK interlocked with the braking operation member BP and an input cylinder CN. The regenerative coordination unit YK is provided with an input chamber Rn connected to the simulator SS via the simulator fluid path HS. Inside the input chamber Rn, the gap Ks between the master piston PM and the input piston PK is controlled by the adjusting hydraulic pressures Pa, Pb, and Pc. Regeneration cooperative control is achieved by controlling the gap Ks between the master piston PM and the input piston PK by the adjusting hydraulic pressures Pa, Pb, and Pc inside the input chamber Rn.

The simulator fluid path HS is provided with an input chamber orifice OR. In the orifice OR, when the operating speed dB is equal to or less than the first predetermined value da, there is no resistance to the flow of the braking fluid BF. That is, when the braking operation member BP is operated, the braking liquid BF corresponding to the volume reduction of the input chamber Rn flows into the simulator SS through the first on-off valve VA in the open position. Here, the first predetermined value da corresponds to the operation speed dB when the braking operation member BP is normally operated.

On the other hand, when the operating speed dB becomes the second predetermined value db or more, which is much larger than the first predetermined value da, the orifice OR becomes a resistance to the flow of the braking liquid BF. Here, the second predetermined value db is a value corresponding to a sudden operation of the braking operation member BP. When “dB ≧ db”, even if the first on-off valve VA is in the open position, the resistance of the orifice OR makes it difficult for the brake fluid BF to move, and the input chamber Rn is put into a confined state. The valve seat hole of the first on-off valve VA can be used as the orifice OR in order to simplify the braking control device SC.

Since the electric pump DC is an on-demand type, it is not operating (in a stopped state) when not braking. In the case of a sudden operation, the resistance of the orifice OR causes the input chamber Rn to be in a state close to a fluid lock. As a result, the operating force Fp of the braking operation member BP operated by the driver is transmitted to the master piston PM via the input chamber Rn. The master piston PM is pressed in the forward direction Ha by the adjusting hydraulic pressures Pa, Pb, Pc, and the operating force Fp of the driver. Therefore, the responsiveness is improved in the increase of the master cylinder hydraulic pressure Pm (that is, the braking hydraulic pressure Pw). In the normal operating state, the orifice OR does not act as a fluid resistance.

The braking control device SC may be provided with a bypass fluid path HD and a check valve GD. The bypass fluid path HD is a fluid path connecting the reservoir RV and the servo chamber Rs. The check valve GD is provided in the bypass fluid path HD and allows the brake fluid BF to move from the reservoir RV to the servo chamber Rs, but prevents the brake fluid BF from moving from the servo chamber Rs to the reservoir RV.

When the braking operation member BP is suddenly operated, a situation may occur in which the increase in the adjusting hydraulic pressure Pa is insufficient with respect to the increase in the operating force Fp. The bypass fluid path HD is provided in parallel with the pressure regulating fluid path HC including the pressure regulating valves UA, UB, and UC, and the reservoir RV and the servo chamber Rs are connected to each other. Further, the bypass fluid path HD is provided with a check valve GD, and in the movement of the braking fluid BF, the movement of “RV → Rs” is permitted, but the movement of “Rs → RV” is prohibited. As a result, even if the rise of the adjusted hydraulic pressures Pa, Pb, and Pc is delayed, the braking fluid BF can flow into the servo chamber Rs via the bypass fluid path HD, so that the master hydraulic pressure Pm is increased. Responsiveness can be guaranteed.

The braking control device SC (particularly, the master unit YM) is provided with a reaction force chamber Ro in which the volume Vo decreases when the volume Vs of the servo chamber Rs increases. The reaction chamber Ro is connected to the simulator SS and the input chamber Rn via the simulator fluid path HS. Then, the reservoir fluid passage HT is connected between the first on-off valve VA of the simulator fluid passage HS and the reaction force chamber Ro, and finally is connected to the reservoir RV. The reservoir fluid passage HT is provided with a second on-off valve VB. The second on-off valve VB is a normally open solenoid valve having a second open position for communicating the reaction chamber Ro and the reservoir RV and a second closed position for blocking the reaction chamber Ro and the reservoir RV. The second on-off valve VB is driven by the controller ECU to the second closed position when the sudden operation is denied, and to the second open position when the sudden operation is affirmed.

Inside the simulator SS, elastic bodies Ds are provided so as to generate an operating force Fp. Further, in the simulator SS, the simulator orifice Os is provided in the inflow hole of the braking fluid BF so that the operation characteristics are well maintained by the damping effect. When the master piston PM is moved in the forward direction Ha, the braking fluid BF is discharged from the reaction chamber Ro. When the brake fluid BF flows into the simulator SS, fluid resistance due to the elastic body Ds and the orifice Os may occur. However, in the sudden operation state, the second on-off valve VB is opened, and the braking fluid BF is returned from the reaction chamber Ro to the reservoir RV via the fluid passages HS and HT. Therefore, when the master piston PM advances, the braking fluid BF in the reaction chamber Ro is discharged without resistance, so that the responsiveness of the master hydraulic pressure Pm can be effectively achieved.

<Other embodiments>
Hereinafter, other embodiments will be described. In other embodiments, the same effect as described above is obtained.
In the above embodiment, as the linear type pressure regulating valves UA, UB, and UC, those whose valve opening amount is adjusted according to the energization amount are adopted. For example, the pressure regulating valves UA, UB, and UC may be on / off valves, but the opening / closing of the valves may be controlled by the duty ratio and the hydraulic pressure may be controlled linearly.

In the above embodiment, the configuration of the disc type braking device (disc brake) has been exemplified. In this case, the friction member is a brake pad and the rotating member is a brake disc. A drum type braking device (drum brake) may be adopted instead of the disc type braking device. In the case of drum brakes, brake drums are used instead of calipers. The friction member is a brake shoe, and the rotating member is a brake drum.

In the above embodiment, the pressure regulating fluid path HC is connected to the first reservoir fluid path HV at the site Bv to form a reflux path. The pressure-regulating fluid passage HC is connected to the reservoir RV (particularly, the pressure-regulating reservoir chamber Rd), and a reflux path can be formed including the reservoir RV (see the fluid passage shown by the two-dot chain line in FIGS. 1 and 5). ). With this configuration, the suction of gas by the fluid pump QC can be suppressed.

In the above embodiment, a single type master cylinder CM having one master chamber Rm is adopted, and one of the front wheel wheel cylinder CWf and the rear wheel wheel cylinder CWr is connected to the master cylinder CM. The other of the front wheel wheel cylinder CWf and the rear wheel wheel cylinder CWr was connected to the pressure regulating fluid path HC. Instead of this, a tandem type master cylinder CM is adopted, one of the two hydraulic chambers of the master cylinder CM is connected to the front wheel cylinder CWf, and the other of the two hydraulic chambers of the master cylinder CM is rear. Can be connected to a wheel wheel cylinder CWr. Further, in the configuration according to the first embodiment (in which the hydraulic pressure Pa is adjusted by one pressure regulating valve UA) in which the tandem type master cylinder CM is adopted, the diagonal type (diagonal type) is used instead of the front-rear type fluid passage. A fluid path (also referred to as "X-type") may be used. It should be noted that the adoption of the single type master cylinder CM is more suitable in terms of mountability on a vehicle because the dimensions of the braking control device SC in the longitudinal direction are shortened.

In the above embodiment, the first on-off valve VA and the second on-off valve VB are energized with the start switch on. Instead of this, the first on-off valve VA may be set to the open position and the second on-off valve VB may be set to the closed position after it is determined that "braking is in progress". As described above, the determination during braking is determined based on at least one of the braking operation amount Ba and the operation signal St (see step S140 in FIG. 3).

SC ... Braking control device, ECU ... Controller, BP ... Braking operation member, ECU ... Controller, CM ... Master cylinder, CW ... Wheel cylinder, YC ... Pressure control unit, DC ... Electric pump (fluid pump QC + electric motor MC), UA , UB, UC ... Electromagnetic valve (pressure regulating valve), YM ... Master unit, PM ... Master piston, YK ... Regenerative coordination unit, CN ... Input cylinder, PK ... Input piston, OR ... Input chamber orifice, SS ... Stroke simulator, Rm ... master room, Rs ... servo room, Ro ... reaction force room, Rn ... input room, VA ... first on-off valve, VB ... second on-off valve, PS ... simulator hydraulic pressure sensor, PN ... input hydraulic pressure sensor, PA, PB, PC ... Adjusting hydraulic pressure sensor, HS ... Simulator fluid path, HD ... Bypass fluid path, HT ... Reservoir fluid path, GD ... Check valve.

Claims (2)

A vehicle braking control device that pumps brake fluid to the wheel cylinders of the wheels of the vehicle and generates braking torque to the wheels in response to the operation of the braking operation member of the vehicle.
A simulator that applies an operating force according to the operation to the braking operation member,
It consists of a master cylinder and a master piston.
A master unit connected to the wheel cylinder, and a master unit having a servo chamber that applies a forward force facing the backward force applied to the master piston by the master chamber to the master piston.
It is composed of an electric pump that sucks the braking fluid from the reservoir of the vehicle and a solenoid valve.
A pressure regulating unit that adjusts the braking fluid discharged by the electric pump to an adjusting hydraulic pressure by the solenoid valve and introduces the adjusting hydraulic pressure into the servo chamber.
It is composed of an input piston interlocking with the braking operation member and an input cylinder connected to the simulator via a simulator fluid path.
A regenerative coordination unit in which the gap between the master piston and the input piston is controlled by the adjusting hydraulic pressure,
Equipped with
When the speed of the operation is equal to or less than the first predetermined value, the simulator fluid path does not become a resistance to the flow of the braking fluid, and the speed of the operation is larger than the first predetermined value. A vehicle braking control device provided with an orifice that acts as a resistance to the flow of the braking fluid when the value is equal to or higher than a predetermined value. The vehicle braking control device according to claim 1.
A bypass fluid path connecting the reservoir and the servo chamber,
A check valve provided in the bypass fluid path that allows the brake fluid to move from the reservoir to the servo chamber but prevents the brake fluid from moving from the servo chamber to the reservoir.
A vehicle braking control device.

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