CN101407211A - Brake control apparatus and process - Google Patents

Brake control apparatus and process Download PDF

Info

Publication number
CN101407211A
CN101407211A CNA2008101683306A CN200810168330A CN101407211A CN 101407211 A CN101407211 A CN 101407211A CN A2008101683306 A CNA2008101683306 A CN A2008101683306A CN 200810168330 A CN200810168330 A CN 200810168330A CN 101407211 A CN101407211 A CN 101407211A
Authority
CN
China
Prior art keywords
pressure
master cylinder
foundation
cylinder pressure
brake
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
CNA2008101683306A
Other languages
Chinese (zh)
Other versions
CN101407211B (en
Inventor
保坂元明
铃木达也
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Nissan Motor Co Ltd
Original Assignee
Nissan Motor Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Nissan Motor Co Ltd filed Critical Nissan Motor Co Ltd
Publication of CN101407211A publication Critical patent/CN101407211A/en
Application granted granted Critical
Publication of CN101407211B publication Critical patent/CN101407211B/en
Expired - Fee Related legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Landscapes

  • Regulating Braking Force (AREA)

Abstract

The present invention provides a brake control apparatus and method. The brake control apparatus includes a fluid pressure sensor to sense an actual master cylinder pressure, a pump to suck a brake fluid from the master cylinder through a hydraulic circuit connecting the master cylinder to a wheel cylinder and a controller to perform a brake assist control to supply a discharge pressure of the pump to the wheel cylinder in accordance with the sensed actual master cylinder pressure signal. The controller calculates a modified master cylinder pressure by modifying the actual master cylinder pressure in accordance with an operating condition of the pump, calculates a base pressure in accordance with a variation of the modified master cylinder pressure, and calculates a target wheel cylinder pressure in accordance with the base pressure, to control a braking force by controlling an actual wheel cylinder pressure of the wheel cylinder in accordance with the target wheel cylinder pressure.

Description

Brake control apparatus and method
Technical field
The present invention relates to equipment and/or the method for control brake power-assisted with braking force.
Background technology
The brake boost control system is configured to the brake fluid drawn for using pump by to wheel cylinder (wheel cylinder) from master cylinder, produce greater than with the braking force of the cooresponding braking force of brake operating of chaufeur.In the brake boost control process, by pump brake fluid to be discharged from master cylinder, the output signal that therefore is used for the fluid pressure sensor of sensing master cylinder pressure can not suitably be represented the brake operating amount of chaufeur.Therefore, according to the pressure of the sensor signal target setting wheel cylinder of fluid pressure sensor and the pressure of target wheel cylinder of braking force controller of braking distance (brakestroke) sensor that directly is not used for the brake operating amount of sensing chaufeur can not reflect the brake operating amount of chaufeur fully.
Therefore, for the brake operating of reflection chaufeur in brake boost control, the braking force controller that Japanese kokai publication hei 11-20638 communique proposes is configured to use the output signal with the cooresponding correcting value correction of the minimizing fluid pressure sensor of the master cylinder pressure (being represented by output signal) of the brake operating that is not attributable to chaufeur.
Summary of the invention
When operating pumps is independent of the operation control brake power of chaufeur, the pump operated pulsation that is tending towards causing master cylinder pressure.But, do not consider this pulsation in the braking force controller of above-mentioned Japanese documentation.
At the brake boost control period, when pump operated generation was pulsed, target braking force fluctuateed because of pulsation, and this fluctuation makes that braking force is unstable and produces undesirable sensation.
Therefore, the object of the present invention is to provide a kind of brake control apparatus and/or method preventing, and stable deceleration and stopping performance is provided owing to the fluctuation of pump operated pressure of wheel braking cylinder.
According to an aspect of the present invention, brake control apparatus comprises fluid pressure sensor, is used to produce the sensor signal of the actual master cylinder pressure of representing master cylinder; Pump is used for by the hydraulic circuit that is connected to master cylinder brake fluid being drawn to wheel cylinder from master cylinder; And controller, be used for carrying out brake boost control and being supplied to wheel cylinder and making brake fluid flow back to master cylinder from wheel cylinder by hydraulic circuit with discharge pressure with pump according to passing the device signal.Controller calculates the correction master cylinder pressure by the actual master cylinder pressure of service conditions correction according to pump; Calculate the pressure of foundation of the brake operating amount that is used to represent chaufeur according to the variation of revising master cylinder pressure; And calculate the target pressure of wheel braking cylinder according to pressure of foundation, come control brake power by actual wheel cylinder pressure according to target wheel cylinder pressure control wheel cylinder.
Controller can be configured to service conditions (for example discharge rate) according to pump and calculate owing to pump operated estimation (less important) master cylinder pressure and change; Calculate the correction master cylinder pressure by using corresponding to change the actual master cylinder pressure of correction owing to pump operated estimation (less important) master cylinder pressure; The pressure of foundation that actual master cylinder pressure during according to brake boost control beginning and correction master cylinder pressure calculate the brake operating amount of expression chaufeur over time; Calculate the target pressure of wheel braking cylinder according to pressure of foundation; And according to the target pressure of wheel braking cylinder by control wheel cylinder actual wheel cylinder pressure (passing through driving pump) come control brake power.
According to a further aspect in the invention, a kind of brake control method, it utilizes pump to draw brake fluid by the hydraulic circuit that master cylinder is connected to wheel cylinder from master cylinder to come control brake power, actual master cylinder pressure according to sensing is supplied to wheel cylinder and returns brake fluid from wheel cylinder to master cylinder by hydraulic circuit with the discharge pressure with pump by carrying out brake boost control, and brake control method comprises: calculate the correction master cylinder pressure by the actual master cylinder pressure of service conditions correction according to pump; Calculate the pressure of foundation of the brake operating amount of expression chaufeur according to the variation of revising master cylinder pressure; And calculate the target pressure of wheel braking cylinder according to pressure of foundation, to come control brake power according to the actual wheel cylinder pressure of target pressure of wheel braking cylinder by the control wheel cylinder.
In accordance with a further aspect of the present invention, a kind of brake control apparatus, it comprises: fluid pressure sensor, it is used to produce the sensor signal of the actual master cylinder pressure of representing master cylinder; Pump, it is used for drawing brake fluid by the hydraulic circuit that master cylinder is connected to wheel cylinder from master cylinder; And the brake boost function unit, it is used for carrying out brake boost control according to sensor signal and is supplied to wheel cylinder and makes brake fluid return master cylinder from wheel cylinder by hydraulic circuit with the discharge pressure with pump.Described brake boost function unit comprises: estimation section, and it is used for calculating owing to pump operated estimation master cylinder pressure variation according to the fluid discharge of pump; Correcting part, it is used for changing according to actual master cylinder pressure with owing to pump operated estimation master cylinder pressure and calculates the correction master cylinder pressure; The pressure of foundation calculating unit, it is used for calculating pressure of foundation according to the variation of actual master cylinder pressure and correction master cylinder pressure; The goal pressure calculating unit, it is used for calculating the target pressure of wheel braking cylinder according to pressure of foundation; And drive control component, it is used for coming control pump according to the target pressure of wheel braking cylinder, comes control brake power with the actual wheel cylinder pressure by the control wheel cylinder.
Description of drawings
Fig. 1 is the scheme drawing that illustrates according to the vehicle that braking control system is housed of the first embodiment of the present invention.
Fig. 2 is the hydraulic circuit diagram that hydraulic pressure unit (HU) 31 as shown in Figure 1 is shown.
Fig. 3 is the block diagram that the accumulation control system that is formed by braking ECU 32 shown in Figure 1 is shown.
Fig. 4 is the diagram of circuit that the brake boost control and treatment of being carried out by braking ECU 32 is shown.
Fig. 5 is the diagram of circuit that the pressure of foundation computing of correction line pressure calculating part 32a shown in Figure 3 and pressure of foundation calculating part 32b execution is shown.
Fig. 6 illustrates the figure that is determined the figure that the estimation master cylinder pressure changes by pump delivery (or pump pressure increment).
Fig. 7 is the diagram of circuit that the end process of carrying out among the pressure of foundation calculating part 32b shown in Figure 3 is shown.
Fig. 8 is the diagram of circuit that the gain calculating processing of carrying out among the goal pressure calculating part 32c shown in Figure 3 is shown.
Fig. 9 is the diagram of circuit that the goal pressure computing of carrying out in the goal pressure calculating part shown in Figure 3 is shown.
Figure 10 be when chaufeur being shown depressing brake pedal BP consistently according to the actual master cylinder pressure of first embodiment, revise master cylinder pressure, pressure of foundation and the time dependent figure of target pressure of wheel braking cylinder.
Figure 11 be illustrate brake pedal BP when constant pressed status is further depressed according to the actual master cylinder pressure of first embodiment, revise master cylinder pressure, pressure of foundation and the time dependent figure of target pressure of wheel braking cylinder.
Figure 12 be illustrate brake pedal BP from constant pressed status slightly during return according to the actual master cylinder pressure of first embodiment, revise master cylinder pressure, pressure of foundation and the time dependent figure of target pressure of wheel braking cylinder.
Figure 13 illustrates the actual master cylinder pressure that is used to illustrate according to the operation of the control system of first embodiment, revises master cylinder pressure, pressure of foundation and the time dependent figure of target pressure of wheel braking cylinder.
Figure 14 be illustrate be used for illustrating brake pedal BP when the end process process is pressed down once more according to the actual master cylinder pressure of the operation of the control system of first embodiment, revise master cylinder pressure, pressure of foundation and the time dependent figure of target pressure of wheel braking cylinder.
Figure 15 is the figure that illustrates according to the hydraulic circuit of the hydraulic pressure unit of another embodiment.
The specific embodiment
The schematically illustrated vehicle that braking control system (or equipment) is housed of Fig. 1 according to the first embodiment of the present invention.Hydraulic pressure unit (HU) (or hydraulic pressure regulator) 31 is under the control of brake controller (braking ECU) 32, and control is used for the pressure of wheel braking cylinder of each wheel cylinder W/C of the near front wheel (FL), off hind wheel (RR), off front wheel (FR) and left rear wheel (RL) in pressure maintenance pattern, pressure increase mode and pressure minimizing pattern.
Braking ECU 32 installs the input information of collecting about the vehicle operating condition from each sensor and other, determines whether carry out control of braking according to input information, and modulated pressure unit (HU) 31 is to keep, to increase or reduce the pressure of wheel braking cylinder of each wheel cylinder.In this example, braking ECU 32 by the CAN communication system from the vehicle behavior sensor 33 that is used for senses vehicle yaw-rate and vehicle lateral acceleration, wheel speed sensors 34, engine controller (ENGCU) 35 and automatic speed changing (automatic transmission) controller (ATCU) the 36 reception information of wheel speed of four wheels that are used for senses vehicle.Braking ECU 32 is the steering angle sensor 39 reception information from being used for sensing bearing circle angle also.According to information from these sensors and controller reception, braking ECU 32 control pressure of wheel braking cylinder.
Brake pedal BP is by the input media of pilot control with abrupt deceleration vehicle.Electric braking servo-unit 41 amplifies the brake pedal operational ton of the chaufeur that is applied to brake pedal BP with predetermined amplification rate.The braking input of being amplified by brake servo unit 41 is converted to fluid pressure by master cylinder M/C.The fluid pressure that is so produced by master cylinder M/C is fed to each wheel cylinder M/C by HU31, with cooresponding one in four wheels of abrupt deceleration vehicle.
Acceleration pedal AP is by the input media of pilot control with accelerating vehicle.According to the accelerator operation of chaufeur, the driving engine 37 of ENGCU35 control vehicle.In addition, ENGCU 35 transmits the information of the accelerator-pedal operation amount of the torque that produces about driving engine 37 and chaufeur by communication system (CAN).The automatic transmission with hydraulic torque converter 38 of ATCU 36 control vehicles.In addition, ATCU 36 is by the information of communication system (CAN) transmission about gear signal (travel position of automatic transmission with hydraulic torque converter 38 (range position)).
Fig. 2 illustrates the hydraulic circuit of the HU31 of the brake system that is used for Fig. 1.HU31 comprises P system and S system, and HU31 has the matched tube structure that is called as the X pipe arrangement.The P system is connected to wheel cylinder W/C (FL) that is used for the near front wheel and the wheel cylinder W/C (RR) that is used for off hind wheel, and the S system is connected to wheel cylinder W/C (FR) that is used for off front wheel and the wheel cylinder W/C (RL) that is used for left rear wheel.P system and S system comprise pump PP or PS respectively.The pump PP of P system and S system and pump PS are driven by a public electrical motor M.Pump can be the pump of plunger pump, gear type pump or other known types.Taking cost into account plunger pump is more satisfactory, and gear type pump is gone up better in flatness (controllability).
In P side and S side, master cylinder M/C is connected with inlet (suction) side of pump P (PP or PS) by fluid passage 11 (11P or 11S).In this fluid passage 11 (11P or 11S), be provided with access valve (gate-in valve) 2 (2P or 2S), this access valve 2 (2P or 2S) is the electromagnetic valve of closed type.
In the fluid passage 11 between pump P and access valve 2, be provided with boiler check valve 6 (6P or 6S), this boiler check valve 6 is configured to allow the direction of brake fluid edge from access valve 2 to pump P to flow and prevents mobile in opposite direction.
Outlet (discharge) side of the pump P of each side in P system and the S system connects by fluid passage 12 (12P or 12S) and each wheel cylinder of being connected P system or S system.The fluid passage 12P of P system is divided into two path (branch) 12FL and 12RR at tapping point, and these two path 12FL and 12RR are respectively arranged with normal-open electromagnetic valve 4FL and the 4RR that is used for wheel cylinder W/C (FL, RR).The fluid passage 12S of S system is divided into two path (branch) 12FR and 12RL at tapping point, and these two path 12FR and 12RL are respectively arranged with the electromagnetic valve 4FR and the 4RL of the open type that is used for wheel cylinder W/C (FR, RL).Electromagnetic valve or supercharger control valve in these electromagnetic valves 4FL, 4RR, 4FR and 4RL are called as.
Each side of fluid passage 12 between pump P and tapping point all is provided with boiler check valve 7 (7P or 7S), and this boiler check valve 7 (7P or 7S) is configured to allow fluid to flow and prevent that fluid from flowing in opposite direction along the direction from the inside electromagnetic valve 4 of pump P.
Each tributary circuit 12 (12FL, 12RR, 12FR and 12RL) all is provided with the bypass path 17 (17FL, 17RR, 17FR or 17RL) of the cooresponding access valve 4 of bypass, and boiler check valve 10 (10FL, 10RR, 10FR or 10RL) is set in each bypass path 17.Boiler check valve 10 in each bypass path 17 all is configured to allow the direction of fluid edge from wheel cylinder to pump P to flow and prevents that fluid from flowing in opposite direction.
Master cylinder M/C is connected with fluid passage 12 (12P or 12S) by fluid passage 13 (13P or 13S).The tapping point of fluid passage 12 and 13 between pump P and interior electromagnetic valve 4 is bonded together.Be provided with outlet valve (gate-out valve) 3 (3P or 3S) in fluid passage 13, this outlet valve 3 (3P or 3S) is the electromagnetic valve of open type.
Each fluid passage 13 (13P and 13S) is provided with the bypass path 18 (18P or 18S) of the cooresponding outlet valve 3 of bypass, and boiler check valve 9 (9P or 9S) is set in each bypass path 18.Boiler check valve 9 in each bypass path 18 all is configured to allow fluid along flowing and prevent that fluid from flowing in opposite direction to the direction of wheel cylinder from master cylinder M/C.
Entrance side at pump P is provided with receiver (reservoir) 16 (16P or 16S), and this receiver 16 is connected with pump P by fluid passage 15 (15P or 15S).Be provided with boiler check valve 8 (8P or 8S) between receiver 16 and the pump P, flow to pump P from receiver 16, and prevent that fluid from flowing in opposite direction to allow fluid.
Fluid passage 15 is connected with wheel cylinder by fluid passage 14 (14P or 14S).The point place of fluid passage 14 between boiler check valve 8 and receiver 16 engages with fluid passage 15.Electromagnetic valve outside being provided with in fluid passage 14 (solenoid-out valve) (pressure reduction control valve) 5 (5FL and 5RR or 5FR and 5RL), this outer electromagnetic valve 5 is the electromagnetic valve of closed type.
In the fluid passage between master cylinder M/C and gate valve 3 (3P or 3S) and 2 (2P or 2S) master cylinder pressure sensor 42 (42P or 42S) is set.Master cylinder pressure sensor 42 is as fluid pressure sensor, to produce the pressure signal or the sensor signal of the actual master cylinder pressure that expression senses.
According to incoming signal from each sensor, braking ECU 32 based on the brake operating of chaufeur, ABS (Anti-lock Braking System) control (ABS) and as the vehicle behavior that waits of vehicle dynamic control (VDC) control and carry out normal control of braking and operate, and calculate the required target braking force of vehicle, control the pressure of wheel braking cylinder of each wheel cylinder.
In addition, braking ECU 32 carry out brake boost control with produce greater than with the braking force of the cooresponding braking force of brake operating of chaufeur.In this embodiment, the form of brake boost control is the accumulation control (buildup control) of the accumulation characteristics of simulating brake pad.This accumulation control will be described below.
Self-moving vehicle uses brake shoe to come brake wheel.When keeping the constant brake operating that continues of brake pedal downforce (or brake operating amount or brake pedal depression degree or downforce), the brake operating that should continue makes pad temperature raise, friction coefficient increases, thereby increases braking force gradually.The phenomenon that this braking force increases gradually is called as the accumulation characteristics of brake shoe.This accumulation characteristics depends on the material of brake shoe largely.
Therefore, the brake system of early stage technology is designed to reach required accumulation characteristics by the brake pad material of selecting to have desired properties.In addition, propose not to be subjected to the influence of brake shoe material behavior or except the influence of brake pad material characteristic, to produce required accumulation characteristics by brake-power control.
In the example shown in first embodiment, when the operating speed of brake pedal BP is in preset range, promptly when the output signal of master cylinder pressure sensor 42 is positioned at preset range, control system increases pressure of wheel braking cylinder gradually by increasing desired deceleration in time, thereby guarantees the sensation in the braking effect increase in braking later stage.When car speed began to equal the predetermined low-speed threshold value, this accumulation control finished.
Fig. 3 illustrates the structure as the braking ECU 32 of the controller of accumulation control system (with as the component parts as the brake boost function unit).
The pump delivery (perhaps pressure excess) that correction shown in Figure 3 (or estimation) master cylinder pressure calculating part 32a (can be used as correction (or estimation) master cylinder pressure calculating unit) is configured to according to pump P calculates the variation of estimation master cylinder pressure, and calculates the correction master cylinder pressure according to the variation of estimation master cylinder pressure with by the actual master cylinder pressure that the sensor signal of master cylinder pressure sensor 42 is represented.Revising master cylinder pressure is the estimation master cylinder pressure of having eliminated the influence of pump P through correction.
Pressure of foundation calculating part 32b (can be used as the pressure of foundation calculating unit) is configured to calculate pressure of foundation according to the actual master cylinder pressure in brake boost when beginning control with by the variation (or variable quantity) of revising the correction master cylinder pressure that master cylinder pressure calculating part 32a calculates.Pressure of foundation is as the estimation master cylinder pressure of the brake operating amount of expression chaufeur.
The pressure of foundation that the target wheel cylinder calculation of pressure 32c of portion (can be used as the goal pressure calculating unit) is configured to calculate according to pressure of foundation calculating part 32b calculates the target pressure of wheel braking cylinder.Drive control part 32d comes control pump P according to the target pressure of wheel braking cylinder that is calculated by the target wheel cylinder calculation of pressure 32c of portion by driving command being sent to pump P.Simultaneously, drive control part 32d is by transmitting opening/closing instruction control gate valve 2 and 3.
In brake boost (accumulation) control process, when pressure of wheel braking cylinder is increased, ECU 32 opens access valve 2 from common state shown in Figure 2, utilize pump P to suck brake fluid from master cylinder M/C, and brake fluid is supplied to wheel cylinder W/C by fluid passage 12 by fluid passage 11.Simultaneously, ECU 32 closes outlet valve 3 and returns master cylinder M/C from wheel cylinder W/C by path 13 to prevent brake fluid.On the other hand, in the accumulation control process, when pressure of wheel braking cylinder reduced, ECU 32 stopped pump P, closes access valve 2, opens outlet valve 3, thereby made brake fluid return master cylinder M/C from wheel cylinder W/C by fluid passage 13.
[brake boost control]
Fig. 4 is illustrated in the conventional time gap in predetermined control cycle (time), by the brake boost control and treatment of braking ECU 32 execution.
In step S1, whether ECU 32 (in revising master cylinder pressure calculating part 32a) comes check stop pedal BP to be depressed by chaufeur by checking the actual master cylinder pressure by master cylinder pressure sensor 42 sensings.If "Yes", then ECU 32 enters step S2; If "No", then ECU 32 enters the end block (returning) of the flow process of Fig. 4.
In step S2, ECU 32 (in revising master cylinder pressure calculating part 32a) checks whether predetermined brake boost executive condition satisfies.If "Yes", then ECU 32 enters step S3 from step S2; If "No", then ECU 32 enters the end block (returning) of the flow process of Fig. 4.In this example, when actual master cylinder pressure remained in the preset range, ECU 32 was judged to be chaufeur and depresses brake pedal consistently, and the brake boost executive condition satisfies.
In step S3, ECU 32 (in revising master cylinder pressure calculating part 32a and pressure of foundation calculating part 32b) carries out pressure of foundation computing as shown in Figure 5, as described later.After step S3, ECU 32 enters step S4.
In step S4, ECU 32 (in pressure of foundation calculating part 32b) carries out end process as shown in Figure 7, as described later.After step S4, ECU 32 enters step S5.
In step S5, the gain calculating that ECU 32 (in goal pressure calculating part 32c) carries out is as shown in Figure 8 handled, as described later.After step S5, ECU 32 enters step S6.
In step S6, the target wheel cylinder calculation of pressure that ECU 32 (in goal pressure calculating part 32c) carries out is as shown in Figure 9 handled, as described later.After step S6, ECU 32 stops processing shown in Figure 4 by entering end block (returning).
[pressure of foundation calculating]
Fig. 5 is the diagram of circuit that illustrates according to the control flow of the pressure of foundation computing of carrying out in revising (or estimation) master cylinder pressure calculating part 32a and pressure of foundation calculating part 32b of first embodiment.
In step S31, ECU 32 is by checking that whether having set end (control) mark (flag) checks whether end process (as shown in Figure 7) is carrying out.If "Yes", then ECU 32 stops the processing of Fig. 5, if "No", then ECU 32 enters step S32 from step S31.
In step S32, ECU 32 calculates in revising master cylinder pressure calculating part 32a and revises (or estimation) master cylinder pressure, and checks out the deviation between correction master cylinder pressure that calculates and the pressure of foundation that calculates in last (previous) control computation period in pressure of foundation calculating part 32b.In step S32, ECU 32 is absolute value of this deviation (| pressure of foundation-correction pressure |) and predetermined pressure of foundation change threshold relatively, and whether the absolute value of determining this deviation (the current correction master cylinder pressure that calculates in the current control cycle and the deviation between the last pressure of foundation that calculates in the last control cycle) is less than the pressure of foundation change threshold.If "Yes", then ECU 32 enters step S34 from step S32; If "No", then ECU 32 enters step S33 from step S32.Determine the pressure of foundation change threshold according to variation owing to the correction line pressure of the pulsation of pump P.In this example, the pressure of foundation change threshold is set equal to than the big value of variation owing to the correction line pressure of the pulsation of pump P.
Change by the actual master cylinder pressure of master cylinder pressure sensor 42 sensings with owing to pump operated estimation (less important or unintentionally) master cylinder pressure and to calculate the correction master cylinder pressure.In this example, determine owing to pump operated estimation (less important or unintentionally) master cylinder pressure by the pump driving command that is provided to pump P from drive control part 32d and change.Just, ECU 32 calculates the discharge rate (or pressure excess) of pump P by the driving command that offers pump P, and utilizes figure shown in Figure 6 to calculate estimation (less important or unintentionally) master cylinder pressure by the pump delivery that calculates to change (variable quantity).Then, ECU 32 calculates the correction master cylinder pressure in the Calais by estimating (less important or unintentionally) master cylinder pressure variable quantity mutually with actual master cylinder pressure.
[correction master cylinder pressure]=[actual master cylinder pressure]+[estimating master cylinder pressure variable quantity (pump pressure recruitment)]
Thereby, the wish of not considering chaufeur why, the correction correction that changes (or reducing) by the master cylinder pressure unintentionally that is caused by the pump P that sucks brake fluid from master cylinder with compensation is determined the correction master cylinder pressure by the actual master cylinder pressure of master cylinder pressure sensor 42 sensings.Revise master cylinder pressure equal actual master cylinder pressure with by change owing to pump operated estimation (less important or unintentionally) master cylinder pressure the correction determined and.In this example, correction is set equal to owing to pump operated estimation (less important or unintentionally) master cylinder pressure and changes (absolute value).Therefore, though actual master cylinder pressure be subjected to pump P action influence and reduce, but constant as long as brake pedal presses down, revise master cylinder pressure and just keep constant.
In step S33, ECU 32 checks by deduct (current) with (last) pressure of foundation and revises whether the resulting difference of master cylinder pressure is negative value.If "Yes" ((current) revises master cylinder pressure greater than (last) pressure of foundation), ECU 32 enters step S35 from step S33; If "No" ((current) revised master cylinder pressure and be less than or equal to (last) pressure of foundation), ECU 32 enters step S36 from step S33.
In step S34, ECU 32 pressure of foundation is set at the pressure of foundation that in last control cycle, calculates before value (last pressure of foundation).Then, ECU 32 enters step S37.So unless the deviation between pressure of foundation and the correction master cylinder pressure surpasses the pressure of foundation change threshold, otherwise ECU 32 keeps pressures of foundation constant.
In step S35, in pressure of foundation calculating part 32b, ECU 32 is poor according to the last value (last correction master cylinder pressure) of the correction master cylinder pressure that calculates among the step S32 (current correction master cylinder pressure) and the correction master cylinder pressure that calculates in last control cycle, calculate the variable quantity (recruitment) of revising master cylinder pressure, and calculate pressure of foundation in the Calais mutually by the variable quantity that will revise master cylinder pressure and the pressure of foundation that in last control cycle, calculates (last pressure of foundation).
[pressure of foundation]=[last pressure of foundation]+[revising the variable quantity of master cylinder pressure]
Last pressure of foundation is the value before that is set to the pressure of foundation of initial value at first.In this example, the initial value of last pressure of foundation equals the actual master cylinder pressure of sensing when brake boost control beginning.When actual master cylinder pressure increases and make that the amount of revising the master cylinder pressure increase surpasses the pressure of foundation change threshold of step S32, ECU32 is according to revising master cylinder pressure (just over time, in this example, the current correction master cylinder pressure that calculates in current control cycle deducts the last correction master cylinder pressure that calculates in last control cycle) or increase pressure of foundation to revise master cylinder pressure increment rate in time.
In step S36, ECU 32 sets in pressure of foundation calculating part 32b and finishes (control) mark, with the beginning end process, then enters step S37.When actual master cylinder pressure reduces and make to revise amount that master cylinder pressure reduces and surpasses the pressure of foundation change threshold of step S32, so ECU 32 is set at 1 with end mark, and the end process of beginning Fig. 7.
In step S37,32 pairs of pressures of foundation of ECU and actual master cylinder pressure compare to determine that whether actual master cylinder pressure is less than pressure of foundation.If "Yes", then ECU32 stops the processing of Fig. 5; If "No" then enters step S38 from step S37.In step S38, ECU 32 is set at actual master cylinder pressure with pressure of foundation, then stops the processing of Fig. 5.Thereby, if pressure of foundation less than actual master cylinder pressure, then pressure of foundation is set equal to actual master cylinder pressure.
Pressure of foundation computing among Fig. 5 is designed to come from pressure of foundation and actual line pressure by the operation of selecting higher value, determine pressure of foundation, though with at pressure of foundation because sensor noise or some other factor prevent that goal pressure is less than actual master cylinder pressure when departing from value corresponding to actual master cylinder pressure.
[end process]
Fig. 7 is the diagram of circuit that illustrates according to the end process of the step S4 that carries out in pressure of foundation calculating part 32b of first embodiment.
In step S41, ECU 32 checks whether be set with end (control) mark.If "Yes", then ECU 32 enters step S42 from step S41; If "No", then ECU 32 stops the processing of Fig. 7.In this example, in case set end mark in step S36, then ECU 32 does not enter the part of the step S32～S38 among Fig. 5, but enters the step S42 of Fig. 7.
In step S42, ECU 32 checks that whether actual master cylinder pressure changes greater than the correction line pressure variation owing to the variation (the perhaps supercharging of pump/decompression changes) of pump delivery.If "Yes", then ECU 32 enters step S43 from step S42; If "No", then ECU 32 enters step S44 from step S42.ECU 32 can be by (at a control cycle in the time) actual master cylinder pressure relatively variation (increases) and (at a control cycle in the time) owing to the variation (increases) that pump operated estimation (less important or unintentionally) master cylinder pressure changes, survey chaufeur and press down the brake pedal of deeper depressing brake pedal in the process once more at minimizing or release brake pedal and operate.When the increase of actual master cylinder pressure during greater than the variation that changes owing to pump operated estimation (unintentionally) master cylinder pressure, braking ECU 32 judges that reducing rear brake pedal in brake pedal depression is depressed once more.
In step S43, ECU 32 determines pressure of foundation in the Calais by changing owing to main (or having a mind to) master cylinder pressure of the brake operating of chaufeur mutually with last pressure of foundation, and enters step S45.Mainly (or have a mind to) the master cylinder pressure variation is to be attributable to the master cylinder pressure of the brake operating of chaufeur to change, and the variation of less important (unintentionally) master cylinder pressure is to be attributable to pump operated master cylinder pressure to change.Can determine main master cylinder pressure variation by from the variation of actual master cylinder pressure, deducting the variation that changes (increase or reduce) based on the estimation of pump delivery less important (unintentionally) master cylinder pressure owing to the operation of chaufeur.
[pressure of foundation]=[last pressure of foundation]+[owing to the main master cylinder pressure variable quantity of the brake operating of chaufeur]
In step S44, ECU 32 determines pressure of foundation by deduct the maximum variable quantity of revising master cylinder pressure from last pressure of foundation.The maximum variable quantity of revising master cylinder pressure is the maximum decrease of the correction master cylinder pressure that calculates in the end process process.Thereby after end process began, pressure of foundation reduced to revise the maxim that the decline of master cylinder pressure in a control cycle changes.Among step S45 behind step S44 or the step S44, ECU 32 will finish (control) mark and reset to zero, then stop the processing of Fig. 7.
Thereby the braking control system of this embodiment depends on that (or the condition identification) result that determines of step S32, S33 and S42 determines pressure of foundation in the three-mode of second pattern of first pattern of step S35, step S44 or step S43.When the answer of step S32 is the answer of "No" and step S33 when being "Yes", in first pattern of step S35, pressure of foundation is to revise the master cylinder pressure increase of advancing the speed in time.In second pattern of step S44, along with reducing pressure of foundation, the correction master cylinder pressure reduces, even with this mode prevent pressure of foundation reduce that speed reduces or revise master cylinder pressure reduce speed reduce still keep pressure of foundation to reduce speed constant, perhaps be not subjected to the fluctuation of actual master cylinder pressure in this mode and revise master cylinder pressure stepped decline reduce pressure of foundation reposefully with directly influencing.Control system is determined pressure of foundation to reduce to revise the fluctuation of master cylinder pressure size in first pattern, control system determines that in second pattern pressure of foundation is to reduce to revise the fluctuation that reduces speed of master cylinder pressure.
[gain calculating]
Fig. 8 is illustrated in the control flow of the gain calculating processing of carrying out among the target wheel cylinder calculation of pressure 32c of portion.
In step S51, ECU 32 detects whether be set with end mark.When being set with end mark, ECU 32 stops the processing of Fig. 8.When not setting end mark, ECU 32 enters step S52.
In step S52, ECU 32 calculates the gain that is used to calculate the target pressure of wheel braking cylinder, then stops the processing of Fig. 8.The braking control system of this example is opened the counting of counting machine when brake boost control beginning, and increases gain with the increase of counting machine.When counting machine surpassed predetermined count value, gain was retained as steady state value.Thereby gain increases from brake boost control beginning is dull in time.
[goal pressure calculating]
Fig. 9 illustrates the goal pressure computing of carrying out at goal pressure calculating part 32c according to first embodiment.
In step S61, ECU 32 multiplies each other to determine the target pressure of wheel braking cylinder by the pressure of foundation that will determine and the gain of determining in step S5 in step S3 or S4.After step S61, ECU 32 enters step S62.
[goal pressure]=[pressure of foundation] * [gain]
Therefore, even pressure of foundation remains unchanged basically, the target pressure of wheel braking cylinder is passed in time with respect to pressure of foundation and is increased gradually.
In step S62, the target pressure of wheel braking cylinder that ECU 32 will determine in step S61 is compared with actual master cylinder pressure, determines whether goal pressure is higher than actual master cylinder pressure.When goal pressure was higher than actual master cylinder pressure, ECU 32 stopped the processing of Fig. 9.When goal pressure was less than or equal to actual master cylinder pressure, ECU 32 was set at the target pressure of wheel braking cylinder at step S63 and equals actual master cylinder pressure, stops the processing of Fig. 9 then.The goal pressure computing of Fig. 9 is designed to be lower than actual master cylinder pressure by from selecting the operation of higher value to determine goal pressure from the goal pressure that is calculated by pressure of foundation and in the actual master cylinder pressure to prevent that goal pressure from becoming.
So the braking control system of structure is worked as follows.
[fundamental operation of brake boost control]
(a) [constant pedal depression]
When Figure 10 is illustrated in chaufeur and depresses brake pedal BP and keep brake pedal BP depression degree constant, the actual master cylinder pressure (line pressure) of sensing, revise master cylinder pressure (correction pressure) and target pressure of wheel braking cylinder (goal pressure) over time.
Time point t1 place in Figure 10, chaufeur begins to press down brake pedal BP.At time point t2 place, braking maneuver amount (or depression degree) beginning is constant.Therefore, braking control system is in the accumulation control of t2 place beginning as brake boost control.In brake boost control, control flow is the S1 → S2 → S3 → S4 → S5 → S6 in the diagram of circuit among Fig. 3.In this brake boost control, control system is according to target wheel cylinder pressure-driven pump P.Therefore, brake fluid is discharged from master cylinder M/C by the drive amount corresponding to the pump P of target pressure of wheel braking cylinder, and brake fluid is supplied to wheel cylinder W/C.Therefore, actual master cylinder pressure reduces with the increase of target pressure of wheel braking cylinder.In the pressure of foundation computing of Fig. 5, in this case, control flow is S31 → S32 → S34 → S37, and it is constant that pressure of foundation keeps.
The time point t3 of (when counting machine is equal to or greater than predetermined value) when beginning through predetermined time interval from brake boost control, the target pressure of wheel braking cylinder no longer increases, and begins to remain unchanged from time point t3.At time point t4 place, the speed of a motor vehicle becomes to be less than or equal to hangs down speed of a motor vehicle threshold value, does not satisfy the condition of carrying out brake boost control.Therefore, the answer of step S2 shown in Figure 4 becomes "No", so the brake boost control in the diagram of circuit of braking control system termination Fig. 4, and opens outlet valve 3.As a result, brake fluid returns master cylinder M/C from wheel cylinder W/C, and actual master cylinder pressure returns (increase) gradually to the value corresponding to the operation of chaufeur.
(b) [from the constant volume under pressure that increases pedal that presses down]
When Figure 11 illustrates chaufeur further (deeper) depresses brake pedal BP (thereby increasing brake pedal depression degree) from constant pressed status, actual master cylinder pressure, revise master cylinder pressure and target wheel cylinder pressure time histories.
Chaufeur begins to depress brake pedal BP at the t1 place, and to begin constant press operation down at the t2 place with the constant identical mode of mode that presses down of Figure 10.At time point t2a place shown in Figure 11, chaufeur is pressed brake pedal darker.Therefore, actual master cylinder pressure increases, and revising master cylinder pressure also together increases.But the absolute value of the deviation between pressure of foundation and the correction master cylinder pressure is still less than the pressure of foundation change threshold.Therefore, the control flow in the pressure of foundation computing of Fig. 5 is S31 → S32 → S34 → S37, and pressure of foundation remains unchanged.
At time point t2b place, the absolute value of the deviation between pressure of foundation and the correction master cylinder pressure begins more than or equal to the pressure of foundation change threshold.Therefore, the control flow in the pressure of foundation computing of Fig. 5 is S31 → S32 → S33 → S35, and pressure of foundation increases the amount corresponding to the increase of revising master cylinder pressure.Thereafter, identical with the mode of Figure 10, the target pressure of wheel braking cylinder increases gradually with respect to basis of constant pressure.
(c) [reduce the pedal depression amount] from constant pressing down
When Figure 12 illustrates chaufeur and makes brake pedal BP from constant pressed status return (reduce brake pedal depression degree), actual master cylinder pressure, revise master cylinder pressure and target wheel cylinder pressure time histories.
Chaufeur begins to depress brake pedal BP at the t1 place, and to begin constant press operation down at the t2 place with the constant identical mode of mode that presses down of Figure 10.At time point t2c place shown in Figure 12, chaufeur reduces the volume under pressure of brake pedal by making the brake pedal return.Therefore, actual master cylinder pressure reduces from the constant level that presses down, and revises master cylinder pressure and also reduces with the minimizing of actual master cylinder pressure.But the absolute value of the deviation between pressure of foundation and the correction master cylinder pressure is still less than the pressure of foundation change threshold.Therefore, the control flow in the pressure of foundation computing of Fig. 5 is S31 → S32 → S34 → S37, and it is constant that pressure of foundation is held.
At time point t2d place, the absolute value of the deviation between pressure of foundation and the correction master cylinder pressure becomes more than or equal to the pressure of foundation change threshold.Therefore, the control flow in the pressure of foundation computing of Fig. 5 is S31 → S32 → S33 → S36 → S37, and (in S36) sets end mark, therefore carries out finishing control in the step S 4 of Fig. 4.In the finishing control of Fig. 7 was handled, control flow was S41 → S42 → S43 → S44 → S45.Therefore, pressure of foundation reduces the cooresponding amount of variation owing to the operation of chaufeur with master cylinder pressure, and pressure of foundation becomes and equals to revise line pressure.In with the mode of Figure 10 identical mode target pressure of wheel braking cylinder with respect to basis of constant pressure gradually increased thereafter.
[ladder that forms in the goal pressure when goal pressure reduces (step)]
When goal pressure will increase in brake boost control, braking control system was closed outlet valve 3, opens access valve 2, and according to goal pressure driving pump P.Therefore, pump P sucks brake fluid and by fluid passage 12 brake fluid that pressurizes is supplied to wheel cylinder W/C from master cylinder M/C by fluid passage 11.
In this case, actual master cylinder pressure reduces according to the pressure excess of pump P or the discharge rate of pump P.Therefore, depart from by the actual master cylinder pressure of master cylinder pressure sensor sensing and value, thereby control system can not be reflected to goal pressure fully with the brake operating of chaufeur corresponding to the brake operating amount of chaufeur.Therefore, the purpose of disclosed braking control system is brake boost control by the brake operating of realizing reflecting chaufeur with the decline correction that is not the master cylinder pressure that causes of the brake operating by chaufeur in above-mentioned Japanese kokai publication hei 11-20638 communique.
Yet this braking control system do not consider in the brake fluid that is configured to make when goal pressure reduces in brake boost control wheel cylinder directly returns the hydraulic circuit of master cylinder, with the brake operating of chaufeur irrelevant return the increase of the master cylinder pressure of master cylinder from wheel cylinder owing to brake fluid.Do not consider this increase of master cylinder pressure, braking control system can't realize fully reflecting the brake boost control of the brake operating of chaufeur.
[preventing the ladder in the goal pressure]
When chaufeur reduces the brake operating amount, on the contrary, the maximum slip of the correction master cylinder pressure that calculates in not considering line pressure and revising under the situation of variable quantity of line pressure with the operating process that reduces the brake operating amount at chaufeur according to the braking control system of first embodiment reduces pressure of foundation.
Just, in the pressure of foundation computing of Fig. 5, when the absolute value of the deviation between pressure of foundation and the correction master cylinder pressure surpassed the pressure of foundation change threshold, braking control system carried out the flow process of S31 → S32 → S33 → S36, and the end process of beginning Fig. 7.In the end process of Fig. 7, braking control system carries out the flow process of S41 → S42 → S44 → S45, the difference that the maxim that master cylinder pressure changes in step S44 obtains.
Figure 13 illustrates the actual master cylinder pressure of comparing with the comparative example of the control of not using first embodiment, revise the example of control of first embodiment of master cylinder pressure, pressure of foundation and target wheel cylinder pressure time sheet form.
At time point ta place, chaufeur begins the return operation to reduce pedal depression.Therefore, braking control system is by closing access valve 2 and open outlet valve 3 master cylinder M/C is connected via fluid passage 13 with wheel cylinder W/C, thereby makes brake fluid return master cylinder M/C from wheel cylinder W/C.As a result, line pressure begins to reduce, and revises line pressure and reduces thereupon.
At time point tb place, the absolute value of the deviation between pressure of foundation and the correction line pressure surpasses the pressure of foundation change threshold.Therefore, pressure of foundation begins to reduce.Interim between time point tb and next time point tc, actual master cylinder pressure increases because of brake fluid returns master cylinder M/C from wheel cylinder W/C.
At time point tc place, the correction master cylinder pressure increases with the increase of actual master cylinder pressure, and the absolute value of the deviation between pressure of foundation and the correction master cylinder pressure becomes less than the pressure of foundation change threshold.Therefore, although braking distance continues to reduce, still keep pressure of foundation ((comparative example) pressure of foundation).Therefore, also keep goal pressure ((comparative example) goal pressure).But because chaufeur continues to make the operation of brake pedal BP return, actual master cylinder pressure begins to reduce once more, and pressure of foundation repeatedly reduces and keeps.Therefore, form ladder in the goal pressure, as illustrate shown in the dotted line ((comparative example) goal pressure) of comparative example, these ladders cause braking force to change and pedal sense are worsened.
Otherwise, at time point tb place, when the absolute value of the deviation between pressure of foundation and the correction line pressure surpasses the pressure of foundation change threshold, the braking control system of first embodiment judges that chaufeur reduces the brake operating amount, transfer finishing control to, reduce pressure of foundation with the maximum slip of revising master cylinder pressure.Therefore, the control system of first embodiment can prevent to produce the deterioration of ladder and pedal sense in goal pressure, and the suitable brake boost controller performance of the brake operating that meets chaufeur is provided.
In addition, by using the minimizing of pressure of foundation change threshold check stop operational ton, control system can avoid the variation erroneous judgement of correction line pressure that the pulsation owing to pump P is produced to be the minimizing of brake operating amount.The control system of first embodiment can not be subjected to the pulsation of pump P accurately to survey the minimizing of the brake operating amount of chaufeur with hindering.
[returning brake boost control] by pedal depression subsequently
Figure 14 is when chaufeur is depressed brake pedal BP once more in the end process process, is used to illustrate actual master cylinder pressure according to the operation of the control system of first embodiment, revises the figure of the time schedule of master cylinder pressure, pressure of foundation and goal pressure.At time point td place, because beginning to carry out the operation of brake pedal return, chaufeur formulates operational ton to reduce, estimate that the absolute value of the deviation between line pressure and the pressure of foundation surpasses the pressure of foundation change threshold, control system begins finishing control.In the end process of Fig. 7, control flow is S41 → S42 → S44 → S45.
At time point te place, brake pedal BP is depressed by chaufeur once more.Therefore, the increase of master cylinder pressure becomes greater than the variation based on the correction master cylinder pressure of the variation of pump pressure (increase or reduce), and control system is carried out the flow process of the S41 → S42 → S43 → S45 in the end process of Fig. 7.In step S43, pressure of foundation is set equal to last pressure of foundation and revises the component sum of the brake operating that is attributable to chaufeur of master cylinder pressure variation.Therefore, pressure of foundation increases according to revising master cylinder pressure.Thereby, when chaufeur increases the brake operating amount after the operation that reduces the brake operating amount, according to the control system of first embodiment according to last pressure of foundation and the variation of revising that master cylinder pressure changes owing to the operation of chaufeur calculate pressure of foundation.Therefore, the control system brake pedal that can respond chaufeur in the finishing control treating process presses down and restarts brake boost control reposefully.
Reduce the operation of brake operating amount at chaufeur after, variable quantity and the variable quantity (among S42s) of the revising master cylinder pressure operation that once more increase brake operating amount of surveying chaufeur of control system by actual master cylinder pressure.Therefore, control system can accurately be surveyed the operation that increases the brake operating amount once more of chaufeur.
At time point tf place, constant because braking distance becomes, make pressure of foundation keep constant by the control flow S31 → S32 → S34 → S37 in Fig. 5.
The braking control system of so constructing according to first embodiment can provide following effect or advantage.
(1) braking ECU 32 considers or compensates (compensate) to flow back to the master cylinder pressure variation that master cylinder M/C causes by brake fluid from wheel cylinder W/C, carries out brake boost control by the using compensation result.Therefore, even by mistake increase under the situation of master cylinder pressure make the operation of brake pedal return at chaufeur after, control system also can reflect the brake boost control of the brake operating of chaufeur.
(2) braking ECU 32 comprises: revise master cylinder pressure calculating part 32a, it is used for calculating estimations (less important) master cylinder pressure according to pump delivery (perhaps pressure excess) and changes and be used for going out correction (estimation) master cylinder pressure according to actual master cylinder pressure and estimation (less important) master cylinder pressure change calculations; Pressure of foundation calculating part 32b, it is used for according to the pressure of foundation that calculates the brake operating amount of expression chaufeur in the actual master cylinder pressure in brake boost when beginning control and the variation (every unit time, for example period) of revising master cylinder pressure; And the target wheel cylinder calculation of pressure 32c of portion, it is used for calculating the target pressure of wheel braking cylinder according to pressure of foundation but not directly calculates goal pressure by revising master cylinder pressure.Therefore, braking control system can utilize the variation of revising line pressure, fluctuates by the pump operated pulsating that causes by at the brake boost control period fluid pressure of wheel cylinder being turned back to master cylinder that suppresses line pressure and carries out stable brake boost control.
(3) when the brake operating amount of chaufeur reduces, pressure of foundation calculating part 32b reduces pressure of foundation with controlled slip, and does not consider the variation of actual master cylinder pressure and the variation of correction master cylinder pressure.Particularly, in the example that illustrates, pressure of foundation calculating part 32b reduces pressure of foundation with the maximum slip of the correction line pressure that calculates in the process that reduces in the brake operating amount of chaufeur.Therefore, even in brake pedal return operation, be not attributable under the situation that the increase of master cylinder pressure unintentionally of the operation of chaufeur takes place, braking control system can prevent undesirable ladder in the goal pressure, perhaps undesirable fluctuation in the goal pressure slip, and the deterioration that prevents brake pedal feel, and suitably finish the brake boost control of the brake operating of following chaufeur.
(4) pressure of foundation calculating part 32b is by with pressure of foundation with revise deviation between the master cylinder pressure the reducing of the brake operating amount of surveying chaufeur of comparing with the pressure of foundation change threshold.Therefore, braking control system can accurately survey chaufeur the brake operating amount minimizing and be not subjected to the interference of the pulsation of pump.
When (5) the brake operating amount of chaufeur increases once more after the brake operating amount reduces, first or main (having a mind to) component owing to the brake operating of chaufeur of the variation of pressure of foundation calculating part 32b by use revising master cylinder pressure calculate pressure of foundation.Therefore, if further depress brake pedal during finishing control, then control system can be restarted brake boost control reposefully.
Although describe the present invention, the invention is not restricted to the foregoing description with reference to the first embodiment of the present invention.The various modifications and variations of the foregoing description still can be within the scope of the invention.
For example, hydraulic pressure unit is not limited to structure shown in Figure 2.Figure 15 illustrates another example of the hydraulic pressure unit that is used for alternate figures 2.Hydraulic pressure unit 43 shown in Figure 15 is receiver 16 (16P, 16S) by receiver 20 (20P, 20S) replacement with the difference of the hydraulic pressure unit 31 of Fig. 2, and removes access valve 2 (2P, 2S) and boiler check valve 6 (6P, 6S) and 8 (8P, 8S).
Receiver 20 comprise connect fluid passage 15 and be configured to from master cylinder M/C receive brake fluid the first receiver opening 20a, connect fluid passage 14 and be configured to and receive brake fluid and brake fluid is supplied to the second receiver opening 20b of arrival end of pump P and receiver chamber 20c that the first and second opening 20a and 20b feed from wheel cylinder W/C.Ball valve 20d is disposed in the inboard of the first opening 20a, becomes the bar 20f of the form of separate pieces to be configured to move up and down ball valve 20d in limited travel with ball valve 20d.
Piston 20g is arranged among the 20c of receiver chamber.Piston 20g connects with bar 20f makes piston 20g and bar 20f move.Spring 20h is arranged among the 20c of receiver chamber and is configured to towards ball valve 20d push piston 20g, thereby produces the power of brake fluid being released receiver chamber 20c.
In the receiver 20 of like this structure, ball valve 20d is anchored in valve seat 20e and goes up that brake fluid further flows into receiver chamber 20c when reaching predetermined value with the amount that prevents the brake fluid in being stored in receiver 20.Thereby receiver 20 is configured to prevent that the brake fluid that flows into receiver chamber 20c from exceeding the absorption ability of pump P, thereby prevents that the pressure that is applied to pump P entrance side from becoming excessive.
Do not have in the common control operation of driven hydraulic pressure unit 43 at pump P, ball valve 20d is because master cylinder pressure and against valve seat 20e, thereby makes brake fluid be supplied to wheel cylinder W/C, and not storage in receiver 20.
In brake boost control (accumulation control), under the situation that increases pressure of wheel braking cylinder, braking control system is closed outlet valve 3 and driving pump P.In this state, pump P draws brake fluid from master cylinder M/C, and this brake fluid is supplied to wheel cylinder W/C by fluid passage 12.On the other hand, under the situation that will reduce pressure of wheel braking cylinder, braking control system stops pump P and opens outlet valve 3, makes brake fluid return master cylinder M/C from wheel cylinder W/C by fluid passage 13.Therefore, use the braking control system of hydraulic pressure unit 43 shown in Figure 15 also can carry out brake boost control and the effect identical with first embodiment is provided.
The illustrated embodiment according to the present invention, braking control system comprises: master cylinder M/C, at least one wheel cylinder W/C, be connected fluid pressure sensor and (brake boost) controller of hydraulic pressure unit between master cylinder and the wheel cylinder or regulating control, the actual master cylinder pressure of sensing.Master cylinder is configured to produce master cylinder pressure according to the braking input (operational ton) of chaufeur.Wheel cylinder is configured to produce braking force by receiving pressure of wheel braking cylinder; Hydraulic pressure regulator is configured to produce pressure of wheel braking cylinder by the master cylinder pressure that provides from master cylinder is provided.Hydraulic pressure unit or regulating control comprise pressure of wheel braking cylinder are increased to the pressure source (for example pump) and the hydraulic circuit portion that is connected master cylinder and wheel cylinder that surpasses the master cylinder pressure that is produced by master cylinder.In Fig. 2 and example shown in Figure 15, hydraulic circuit portion comprises at least the first loop sections or the fluid passage 11 that extend to the entrance side of pump P from first meeting point that connects master cylinder, be arranged in second loop sections or the gate valve 3 the fluid passage 13 that extend to second meeting point of the outlet side that connects pump P from first meeting point, be arranged in second meeting point and connect pressure charging valve 4 between the 3rd meeting point of wheel cylinder W/C, be arranged in the receiver 16 that extends to the entrance side that connects pump P from the 3rd meeting point or the reducing valve 5 20 the return loop section 14.
According to one aspect of the invention, brake control apparatus comprises: be used for producing the expression master cylinder actual master cylinder pressure sensor signal fluid pressure sensor, draw the pump of brake fluid and be used to carry out brake boost control from master cylinder by the hydraulic circuit that master cylinder is connected to wheel cylinder to be supplied to wheel cylinder and to make brake fluid flow back to the brake boost function unit of master cylinder by hydraulic circuit from wheel cylinder according to the discharge pressure of sensor signal with pump.Brake boost function unit (or brake boost control method) comprising: (i) estimation section (or step) is used for calculating owing to pump operated estimation master cylinder pressure variation according to the fluid discharge of pump; (ii) correcting part (or step) is used for changing according to actual master cylinder pressure with owing to pump operated estimation master cylinder pressure calculating the correction master cylinder pressure; (iii) pressure of foundation calculating unit (or step) is used for calculating pressure of foundation according to variation and the actual master cylinder pressure of revising master cylinder pressure; (iv) goal pressure calculating unit (or step) is used for calculating the target pressure of wheel braking cylinder according to pressure of foundation; And (v) drive control component (or step) is used for coming control pump to come control brake power with the actual wheel cylinder pressure by the control wheel cylinder according to the target pressure of wheel braking cylinder.Pressure of foundation calculating unit (or step) can comprise identification component (or substep), be used for determining to revise still minimizing of master cylinder pressure increase, in revising master cylinder pressure increase pattern that increases and the minimizing pattern of revising the master cylinder pressure minimizing, pressure of foundation is changed; Pressure of foundation increases parts (or substep), is used in the increase pattern pressure of foundation being increased to reduce to revise the fluctuation of master cylinder pressure with the increase of revising master cylinder pressure; And pressure of foundation minimizing parts (or substep), be used for pressure of foundation being fluctuateed because of the slip of revising master cylinder pressure with the slip that the minimizing of revising master cylinder pressure reduces to prevent pressure of foundation in the minimizing pattern.
The application requires Japan of submitting on October 11st, 2007 patent application No.2007-265082 and Japan of submitting on June 18th, 2008 preceence of patent application No.2008-158593 formerly formerly.The full content of Japanese patent application No.2007-265082 and No.2008-158593 is incorporated in this.
Though describe the present invention with reference to some embodiment of the present invention above, the invention is not restricted to the foregoing description.According to above-mentioned instruction, the person of ordinary skill in the field can make amendment and changes the foregoing description.Protection scope of the present invention is limited by the accompanying claims.

Claims (17)

1. brake control apparatus, it comprises:
Fluid pressure sensor, it is used to produce the sensor signal of the actual master cylinder pressure of representing master cylinder;
Pump, it is used for drawing brake fluid by the hydraulic circuit that described master cylinder is connected to wheel cylinder from described master cylinder; And
Controller, it is used to carry out brake boost control, and to be supplied to described wheel cylinder and to make described brake fluid return described master cylinder from described wheel cylinder by described hydraulic circuit according to the discharge pressure of described sensor signal with described pump, described controller is configured to:
By calculating the correction master cylinder pressure according to the described actual master cylinder pressure of the service conditions correction of described pump,
Calculate the pressure of foundation of the brake operating amount that is used to represent chaufeur according to the variation of described correction master cylinder pressure, and
Calculate the target pressure of wheel braking cylinder according to described pressure of foundation, come control brake power by actual wheel cylinder pressure according to the described wheel cylinder of described target wheel cylinder pressure control.
2. brake control apparatus according to claim 1 is characterized in that, described controller is configured to: calculate owing to pump operated estimation master cylinder pressure variation according to described discharge of pump; Change according to described actual master cylinder pressure with owing to described pump operated described estimation master cylinder pressure and to calculate described correction master cylinder pressure; Described actual master cylinder pressure during according to the variation of described correction master cylinder pressure and brake boost control beginning calculates the described pressure of foundation of the brake operating amount of expression chaufeur, the variation of described correction master cylinder pressure be described correction master cylinder pressure over time; Calculate described target pressure of wheel braking cylinder according to described pressure of foundation; By controlling described braking force according to the described actual wheel cylinder pressure of the described wheel cylinder of described target wheel cylinder pressure control.
3. brake control apparatus according to claim 1 is characterized in that, described controller is configured to: calculate correction according to described discharge of pump and change owing to pump operated estimation master cylinder pressure with compensation; Calculate described correction master cylinder pressure by described actual master cylinder pressure and described correction; Variation according to described correction master cylinder pressure changes described pressure of foundation.
4. brake control apparatus according to claim 1, it is characterized in that, described controller is configured to: when the brake operating amount of chaufeur reduced, the maximum slip of the described correction master cylinder pressure that calculates during reducing with the brake operating amount at chaufeur reduced described pressure of foundation.
5. brake control apparatus according to claim 4, it is characterized in that described controller is configured to: the brake operating amount that the deviation between described pressure of foundation and described correction master cylinder pressure is judged to be chaufeur during more than or equal to predetermined basis pressure change threshold reduces.
6. according to claim 4 or 5 described brake control apparatus, it is characterized in that, first component of the variation of described correction master cylinder pressure calculated the currency of described pressure of foundation when described controller was configured to reduce the back chaufeur and increase described brake operating amount once more according to the last value of described pressure of foundation and described brake operating amount, and described first component of the variation of described correction master cylinder pressure is the variation corresponding to the chaufeur brake operating.
7. brake control apparatus according to claim 6, it is characterized in that described controller is configured to: detection reduces afterwards in described brake operating amount, described brake operating amount reduced the operation that the back chaufeur increases described brake operating amount once more when the variation of described actual master cylinder pressure became greater than the variation of described correction master cylinder pressure.
8. according to each the described brake control apparatus among the claim 1-5, it is characterized in that, described controller is configured to: described target pressure of wheel braking cylinder and the described actual master cylinder pressure that calculates according to described pressure of foundation relatively, and from based on select the described target pressure of wheel braking cylinder of described pressure of foundation and the described actual master cylinder pressure higher one as final objective pressure.
9. according to each the described brake control apparatus among the claim 1-5, it is characterized in that described controller is configured to: the accumulation control that described target pressure of wheel braking cylinder is increased in time gradually.
10. according to each the described brake control apparatus among the claim 1-5, it is characterized in that described controller is configured to: the change calculations according to described correction master cylinder pressure goes out described pressure of foundation, to reduce the fluctuation of described correction master cylinder pressure.
11. each the described brake control apparatus according among the claim 1-5 is characterized in that described controller is configured to: make described pressure of foundation reducing and reduce with described correction master cylinder pressure; Even and the decline of the slip of described correction master cylinder pressure still keeps the slip of described pressure of foundation.
12. according to each the described brake control apparatus among the claim 1-5, it is characterized in that, described controller is configured to: keep described pressure of foundation constant, unless the deviation between described pressure of foundation and the described correction master cylinder pressure surpasses the pressure of foundation change threshold; And the deviation between described pressure of foundation and described correction master cylinder pressure is when surpassing described pressure of foundation change threshold, changes described pressure of foundation according to the variation of described correction master cylinder pressure.
13. brake control apparatus according to claim 12, it is characterized in that, described controller is configured to: when described correction master cylinder pressure increased, the last value that is added to described pressure of foundation by the variation with described correction master cylinder pressure increased described pressure of foundation; And when described correction master cylinder pressure reduces, reduce described pressure of foundation by the variation that from the last value of described pressure of foundation, deducts described correction master cylinder pressure.
14. according to each the described brake control apparatus among the claim 3-5, it is characterized in that, described controller is configured to: the variation of described actual master cylinder pressure greater than described estimation master cylinder pressure change owing to described pump operated variation the time, by with the last value of described pressure of foundation with from the variation of described actual master cylinder pressure, deduct described estimation master cylinder pressure variation determine described pressure of foundation in the Calais mutually owing to remaining surplus after the described pump operated variation.
15. brake control method, it utilizes pump to draw brake fluid by the hydraulic circuit that master cylinder is connected to wheel cylinder from described master cylinder to come control brake power, actual master cylinder pressure according to sensing is supplied to described wheel cylinder and returns described brake fluid from described wheel cylinder to described master cylinder by described hydraulic circuit with the discharge pressure with described pump by carrying out brake boost control, and described brake control method comprises:
By calculating the correction master cylinder pressure according to the described actual master cylinder pressure of the service conditions correction of described pump;
Calculate the pressure of foundation of the brake operating amount of expression chaufeur according to the variation of described correction master cylinder pressure; And
Calculate the target pressure of wheel braking cylinder according to described pressure of foundation, to control described braking force by the actual wheel cylinder pressure of controlling described wheel cylinder according to described target pressure of wheel braking cylinder.
16. a brake control apparatus, it comprises:
Fluid pressure sensor, it is used to produce the sensor signal of the actual master cylinder pressure of representing master cylinder;
Pump, it is used for drawing brake fluid by the hydraulic circuit that described master cylinder is connected to wheel cylinder from described master cylinder; And
The brake boost function unit, it is used for carrying out brake boost control according to described sensor signal and is supplied to described wheel cylinder and makes described brake fluid return described master cylinder from described wheel cylinder by described hydraulic circuit with the discharge pressure with described pump, and described brake boost function unit comprises:
Estimation section, it is used for calculating owing to pump operated estimation master cylinder pressure variation according to the fluid discharge of described pump,
Correcting part, it is used for changing according to described actual master cylinder pressure with owing to described pump operated described estimation master cylinder pressure and calculates the correction master cylinder pressure,
The pressure of foundation calculating unit, it is used for calculating pressure of foundation according to the variation of described actual master cylinder pressure and described correction master cylinder pressure,
The goal pressure calculating unit, it is used for calculating the target pressure of wheel braking cylinder according to described pressure of foundation, and
Drive control component, it is used for controlling described pump according to described target pressure of wheel braking cylinder, to control described braking force by the actual wheel cylinder pressure of controlling described wheel cylinder.
17. brake control apparatus according to claim 16, it is characterized in that, described pressure of foundation calculating unit comprises: identification component, it is used for determining that described correction master cylinder pressure increases or reduces so that described pressure of foundation when described correction master cylinder pressure increases with increase patterns of change, when described correction master cylinder pressure reduces to reduce patterns of change; Pressure of foundation increases parts, and it is used in described increase pattern described pressure of foundation being increased with the increase of described correction master cylinder pressure, to reduce the fluctuation of described correction master cylinder pressure; And pressure of foundation minimizing parts, it is used in described minimizing pattern described pressure of foundation being reduced with the minimizing of described correction master cylinder pressure, fluctuates because of the fluctuation of the slip of described correction master cylinder pressure with the slip that prevents described pressure of foundation.
CN2008101683306A 2007-10-11 2008-09-26 Brake control apparatus and process Expired - Fee Related CN101407211B (en)

Applications Claiming Priority (6)

Application Number Priority Date Filing Date Title
JP2007265082 2007-10-11
JP2007-265082 2007-10-11
JP2007265082 2007-10-11
JP2008158593 2008-06-18
JP2008-158593 2008-06-18
JP2008158593A JP5109826B2 (en) 2007-10-11 2008-06-18 Braking force control device

Publications (2)

Publication Number Publication Date
CN101407211A true CN101407211A (en) 2009-04-15
CN101407211B CN101407211B (en) 2012-06-06

Family

ID=40570480

Family Applications (1)

Application Number Title Priority Date Filing Date
CN2008101683306A Expired - Fee Related CN101407211B (en) 2007-10-11 2008-09-26 Brake control apparatus and process

Country Status (2)

Country Link
JP (1) JP5109826B2 (en)
CN (1) CN101407211B (en)

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102403866A (en) * 2010-08-31 2012-04-04 罗伯特·博世有限公司 Linear Drive Device For Pressure Supply Unit, Pressure Supply Unit, Fluid Device
CN104044567A (en) * 2013-03-13 2014-09-17 福特全球技术公司 Coordinated brake control of wheels on a common differential
CN105377650A (en) * 2013-07-22 2016-03-02 日立汽车系统株式会社 Brake control device
CN106364470A (en) * 2015-07-24 2017-02-01 株式会社电装 Vehicle-use brake apparatus
CN110843750A (en) * 2018-08-21 2020-02-28 Zf主动安全美国有限公司 Method for controlling a vehicle brake system
CN112218817A (en) * 2018-03-06 2021-01-12 科尼起重机全球公司 Method for controlling and in particular monitoring an actuator, in particular of a winch, a lift or a crane, and system for carrying out such a method
US11572051B2 (en) * 2016-12-29 2023-02-07 Robert Bosch Gmbh Evaluation electronics and method for estimating a master brake cylinder pressure in a vehicle brake system equipped with an electromechanical brake booster

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP5395758B2 (en) 2010-07-09 2014-01-22 日立オートモティブシステムズ株式会社 Brake control device

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0928730B1 (en) * 1996-09-26 2004-02-18 Toyota Jidosha Kabushiki Kaisha Braking device
JPH1120638A (en) * 1997-07-08 1999-01-26 Toyota Motor Corp Braking force controller
JP2001260851A (en) * 2000-03-22 2001-09-26 Aisin Seiki Co Ltd Brake control device for vehicle
JP2002137720A (en) * 2000-10-31 2002-05-14 Aisin Seiki Co Ltd Brake controlling device for vehicle
JP2004122818A (en) * 2002-09-30 2004-04-22 Mazda Motor Corp Braking device of automobile
JP4282465B2 (en) * 2003-12-17 2009-06-24 ダイハツ工業株式会社 Vehicle braking method and vehicle braking device

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102403866A (en) * 2010-08-31 2012-04-04 罗伯特·博世有限公司 Linear Drive Device For Pressure Supply Unit, Pressure Supply Unit, Fluid Device
CN102403866B (en) * 2010-08-31 2016-08-24 罗伯特·博世有限公司 Linear drive apparatus, voltage supply unit and fluid device for voltage supply unit
CN104044567A (en) * 2013-03-13 2014-09-17 福特全球技术公司 Coordinated brake control of wheels on a common differential
CN105377650A (en) * 2013-07-22 2016-03-02 日立汽车系统株式会社 Brake control device
CN106364470A (en) * 2015-07-24 2017-02-01 株式会社电装 Vehicle-use brake apparatus
CN106364470B (en) * 2015-07-24 2019-06-14 株式会社爱德克斯 Braking device for vehicle
US11572051B2 (en) * 2016-12-29 2023-02-07 Robert Bosch Gmbh Evaluation electronics and method for estimating a master brake cylinder pressure in a vehicle brake system equipped with an electromechanical brake booster
CN112218817A (en) * 2018-03-06 2021-01-12 科尼起重机全球公司 Method for controlling and in particular monitoring an actuator, in particular of a winch, a lift or a crane, and system for carrying out such a method
CN112218817B (en) * 2018-03-06 2022-08-02 科尼起重机全球公司 Method for controlling and in particular monitoring an actuator, in particular of a winch, a lift or a crane, and system for carrying out such a method
CN110843750A (en) * 2018-08-21 2020-02-28 Zf主动安全美国有限公司 Method for controlling a vehicle brake system
CN110843750B (en) * 2018-08-21 2023-09-05 Zf主动安全美国有限公司 Method for controlling a vehicle brake system

Also Published As

Publication number Publication date
JP5109826B2 (en) 2012-12-26
JP2009107612A (en) 2009-05-21
CN101407211B (en) 2012-06-06

Similar Documents

Publication Publication Date Title
CN101407211B (en) Brake control apparatus and process
CN101734247B (en) Control device for brake apparatus
EP1067032B1 (en) Vehicular brake system
CN102216133B (en) Brake device for vehicle
US8781701B2 (en) Vehicle regeneration cooperative braking system
US6273525B1 (en) Method and device for determining a value representing the system pressure in a brake circuit
US7140699B2 (en) Method for regulating a predetermined modifiable brake pressure
EP2048050B1 (en) Brake control apparatus and process
JP5295750B2 (en) Control device for brake device
US6183052B1 (en) Apparatus and method for controlling behavior of a vehicle
US20060175895A1 (en) Hydraulic brake system with anti-lock control
US20080295506A1 (en) Vehicle behavior control apparatus
JP2001260851A (en) Brake control device for vehicle
US6364429B1 (en) Vehicle brake boost assist control
JP5453752B2 (en) Braking force control device
EP0980803B1 (en) Braking force controller
US6390568B1 (en) Vehicle motion control system
EP1449731A1 (en) Electronically controlled hydraulic brake system
US6522966B2 (en) Method of controlling vehicle hydraulic brake system
US20020043874A1 (en) Vehicle motion control system
US6386647B2 (en) Hydraulic brake apparatus for a vehicle
CN103228509B (en) Be used for the gradual braking device of vehicle and the braking force control method for vehicle
JPH0569815A (en) Slip control device for vehicle
JP2001191909A (en) Automatic brake device
US6595601B2 (en) Method and device for regulating braking effect

Legal Events

Date Code Title Description
C06 Publication
PB01 Publication
C10 Entry into substantive examination
SE01 Entry into force of request for substantive examination
C14 Grant of patent or utility model
GR01 Patent grant
CF01 Termination of patent right due to non-payment of annual fee
CF01 Termination of patent right due to non-payment of annual fee

Granted publication date: 20120606

Termination date: 20180926