CN105667477B - A kind of all-wheel steering electric wheel truck line traffic control hydraulic parking braking system - Google Patents

A kind of all-wheel steering electric wheel truck line traffic control hydraulic parking braking system Download PDF

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Publication number
CN105667477B
CN105667477B CN201610227397.7A CN201610227397A CN105667477B CN 105667477 B CN105667477 B CN 105667477B CN 201610227397 A CN201610227397 A CN 201610227397A CN 105667477 B CN105667477 B CN 105667477B
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China
Prior art keywords
valve
parking
pressure
braking
pipeline
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Expired - Fee Related
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CN201610227397.7A
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Chinese (zh)
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CN105667477A (en
Inventor
杨勇
严运兵
许小伟
王维强
陈涛
郑志阳
沈琪
钱能
叶刚
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Wuhan University of Science and Engineering WUSE
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Wuhan University of Science and Engineering WUSE
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Priority to CN201610227397.7A priority Critical patent/CN105667477B/en
Publication of CN105667477A publication Critical patent/CN105667477A/en
Application granted granted Critical
Publication of CN105667477B publication Critical patent/CN105667477B/en
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Classifications

    • BPERFORMING OPERATIONS; TRANSPORTING
    • B60VEHICLES IN GENERAL
    • B60TVEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
    • B60T8/00Arrangements for adjusting wheel-braking force to meet varying vehicular or ground-surface conditions, e.g. limiting or varying distribution of braking force
    • B60T8/17Using electrical or electronic regulation means to control braking
    • B60T8/171Detecting parameters used in the regulation; Measuring values used in the regulation
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B60VEHICLES IN GENERAL
    • B60TVEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
    • B60T11/00Transmitting braking action from initiating means to ultimate brake actuator without power assistance or drive or where such assistance or drive is irrelevant
    • B60T11/10Transmitting braking action from initiating means to ultimate brake actuator without power assistance or drive or where such assistance or drive is irrelevant transmitting by fluid means, e.g. hydraulic
    • B60T11/24Single initiating means operating on more than one circuit, e.g. dual circuits
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B60VEHICLES IN GENERAL
    • B60TVEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
    • B60T2270/00Further aspects of brake control systems not otherwise provided for
    • B60T2270/10ABS control systems
    • B60T2270/12ABS control systems for all-wheel drive vehicles

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  • Engineering & Computer Science (AREA)
  • Transportation (AREA)
  • Mechanical Engineering (AREA)
  • Regulating Braking Force (AREA)

Abstract

The invention discloses a kind of all-wheel steering electric wheel truck line traffic control hydraulic parking braking system, it is sequentially connected including electric hydraulic pump (2), accumulator (4) and pressure-reducing valve (5) by pipeline, pressure-reducing valve (5) is connected with braking valve for vehicle (6), manual parking valve (7) respectively by pipeline, and then braking valve for vehicle (6), manual parking valve (7) are connected with traveling/parking switching valve (10) respectively by pipeline;Traveling/parking switching valve (10) is connected with the wheel drag (18) of front and back wheel respectively by pipeline;The system is also connected including park brake switch (8) with parking braking ECU (9), and the parking braking ECU (9) is used to gather sensor information and controls each electric executing part.The present invention use line traffic control hydraulic parking braking scheme, the characteristics of adaptation wheel independent steering;It is rapid using pressurization, pressurize and the pressure release of line traffic control electromagnetic hydraulic valve control parking pressure, response;Parking braking hydraulic coupling accumulator and pressure regulator valve with electric hydraulic pump produce, and brake force can be adjusted flexibly;Present system can integrate ABS and ESP functions.

Description

A kind of all-wheel steering electric wheel truck line traffic control hydraulic parking braking system
Technical field
The present invention relates to electric automobile hydraulic parking brake field, specifically a kind of all-wheel steering electric wheel truck With by the line traffic control hydraulic parking braking system of electrohydraulic units offer parking brake force.
Background technology
In order to enable the vehicle to safely be parked on tilted road surface by means of EPB, holding brake device needs Enough parking brake forces can be provided by the wheel on an axletree or whole wheels.In order that vehicle brake can not only Enough use, and can be used as EPB as running brake, holding brake device needs to take into account vehicle braking The service brake and parking braking of device.
The each wheel of all-wheel steering electric wheel truck can independent steering and driving, have good dynamic control special Property, it is a focus of following Development of Electric Vehicles.Due to each of which wheel can independent steering, the parking for orthodox car Brake apparatus can not adapt to the characteristics of whole wheel independent steerings, no longer be applicable.
The content of the invention
The purpose of the present invention is to overcome the shortcomings of the prior art, there is provided a kind of all-wheel steering electric wheel truck line traffic control Hydraulic parking braking system.
The present invention operation principle be:Accumulator is coordinated to produce hydraulic brake pressure using electric hydraulic pump, after pressure regulation Parking hydraulic coupling is provided to brake.When carrying out parking braking, park brake switch, parking braking ECU control row are opened Car/parking switching valve switches to parked state, and braking valve for vehicle works in high-pressure side and parking hydraulic coupling is introduced into four wheel systems Dynamic device, after establishing parking pressure, braking valve for vehicle works in middle position, and each pipeline is closed, and pressure is kept.During parking, Parking pressure sensor is monitored to parking braking loine pressure, maintains parking braking pressure in setting range.
A kind of all-wheel steering electric wheel truck line traffic control hydraulic parking braking system of the present invention, by using motor-driven Hydraulic pump coordinates accumulator to produce parking braking hydraulic pressure;
Vavle switching brakes is switched to parking mode of operation by using traveling/parking;
By braking valve for vehicle to wheel drag pressurization, pressurize and pressure release, carry out parking braking and release parking braking.
A kind of all-wheel steering electric wheel truck line traffic control hydraulic parking braking system of the present invention, including electric hydraulic pump 2, storage Can device 4 and pressure-reducing valve 5 be sequentially connected by pipeline, pressure-reducing valve 5 by pipeline respectively with braking valve for vehicle 6, the phase of manual parking valve 7 Even, then braking valve for vehicle 6, manual parking valve 7 are connected with traveling/parking switching valve 10 respectively by pipeline;Traveling/parking is cut Valve 10 is changed by pipeline respectively with the wheel drag 18 of front and back wheel to be connected;
The system is also connected including park brake switch 8 with parking braking ECU 9, the parking braking ECU 9 are used to gather sensor information and control each electric executing part.
The electric hydraulic pump 2, braking valve for vehicle 6, manual parking valve 7 are connected with brake fluid fuel tank respectively.
First pressure sensor 11 is provided with pipeline between the accumulator 4 and pressure-reducing valve 5, for monitoring accumulator Pressure, Braking system pressure is maintained in the scope of application.
Tie point valve 14 is provided with pipeline between the traveling/parking switching valve 10 and all the way wheel drag 18 With second pressure sensor 12;Set on pipeline between the traveling/parking switching valve 10 and another way wheel drag 18 There are the second bypass valve 15 and the 3rd pressure sensor 13;The pressure sensor 13 of second pressure sensor 12 and the 3rd is used for monitoring car Brake pressure is taken turns, brake pressure is in the scope of application during maintaining parking.
The braking valve for vehicle 6 is three electirc controlling hydraulic reversing valves, and middle position is kept for parking braking hydraulic line pressure, Other two position communicates with pressure piping and hydraulic pressure bleed-off circuit respectively, for producing releasing for parking braking and parking braking Put.
The bypass valve 14,15 is dual circuit arranged crosswise branch road stop valve.
The manual parking valve 7, for parking braking of under malfunction, meeting an urgent need.
Compared with prior art, the beneficial effects of the present invention are:The present invention uses line traffic control hydraulic parking braking scheme, fits The characteristics of answering wheel independent steering;It is fast using pressurization, pressurize and the pressure release of line traffic control electromagnetic hydraulic valve control parking pressure, response Speed;Parking braking hydraulic coupling accumulator and pressure regulator valve with electric hydraulic pump produce, and brake force can be adjusted flexibly;By using Hydraulic accumulator can reduce the usage frequency of electric hydraulic pump, be advantageous to the energy-conservation of battery power supply system;Hydraulic system passes through Switching valve switches service brake and parking braking, and two systems work independently;It is high using dual circuit arranged crosswise, reliability;This Invention system can integrate ABS and ESP functions.
Brief description of the drawings
Fig. 1 is the overall structure diagram of the present invention.
Fig. 2 is the workflow diagram of the present invention.
In figure, 1 is brake fluid fuel tank, and 2 be electric hydraulic pump, and 3 be check valve, and 4 be accumulator, and 5 be pressure-reducing valve, 6 be in Car brake valve, 7 be manual parking valve, and 8 be park brake switch, and 9 be parking braking ECU, and 10 be that traveling/parking switches Valve, 11,12,13 be first, second, third pressure sensor, and 14,15 be first, second bypass valve, and 16 be normally-on two-position two-way Magnetic valve, 17 be normally closed two-position two-way solenoid valve, and 18 be wheel drag.
Embodiment
Below by embodiment, and with reference to accompanying drawing, the invention will be further described.
As shown in figure 1, a kind of all-wheel steering electric wheel truck line traffic control hydraulic parking braking system, including:
Electric hydraulic pump 2, accumulator 4, pressure-reducing valve 5, produce the hydraulic pressure for parking braking;
Braking valve for vehicle 6, manual parking valve 7, traveling/parking switching valve 10, for being controlled to parking hydraulic circuit;
Park brake switch 8, pressure sensor 11,12,13, for line traffic control hydraulic parking device Working mode set and it is System pressure monitoring;
Parking braking ECU(ECU)9, sensor information collection and electric execution element for parking braking system Control.
Reduce the usage frequency of electric hydraulic pump 2 by using hydraulic accumulator 4, in favor of the section of battery power supply system Energy.
Parking brake force is adjusted in the scope of application by using adjustable pressure-reducing valve 5.
Braking valve for vehicle 6 to wheel drag by pressurizeing, pressurize and pressure release, carries out parking braking and releases parking system It is dynamic.
The braking valve for vehicle 6 is three electirc controlling hydraulic reversing valves, and middle position is kept for parking braking hydraulic line pressure, Other two position communicates with pressure piping and hydraulic pressure bleed-off circuit respectively, for producing releasing for parking braking and parking braking Put.
Manual parking valve 7, for parking braking of under malfunction, meeting an urgent need.
Traveling/parking switching valve 10, for switching brakes to parking mode of operation;
Park brake switch 8, is switched using maintenance, for starting parking or releasing parking.
The bypass valve 14,15 is dual circuit arranged crosswise branch road stop valve, improves system reliability.
Parking braking system of the present invention can ensure the function of service braking system, particularly anti-lock braking system ABS and Electronics vehicle body stabilising arrangement ESP.
As shown in Fig. 2 the workflow for parking braking.The park brake switch 8 connects when driver carries out parking It is logical, after parking braking ECU 9 receives the parking of park brake switch 8 instruction, the information of pressure sensor 11 is read, is passed in pressure When the pressure value of sensor 11 is less than preset range, driving electric hydraulic pump 2 works, and stops after pressure reaches preset upper limit value electronic Hydraulic pump 2 works;Meanwhile parking braking ECU 9 to traveling/parking switching valve 10 send control signal, drive to driving/ Parking switching valve 10 works in parking position, and then parking braking ECU 9 sends control signal to braking valve for vehicle 6, drives Dynamic braking valve for vehicle 6 works in left position, and whole wheel drags 18 are connected by pipeline with adjustable pressure-reducing valve 5, begin setting up pressure Power;In pressurization, parking braking ECU 9 receives pressure sensor 12,13 information, judges whether normally to build pressure; As normally established parking pressure, parking braking ECU 9 sends control signal to braking valve for vehicle 6, drives braking valve for vehicle 6 Middle position is worked in, whole pipeline lockings of wheel drag 18 carry out pressurize.Hereafter, during parking, the automatically controlled list of parking braking Member 9 enters control according to the signal of pressure sensor 11 to the start and stop of electric hydraulic pump 2, keeps the pressure of accumulator 4 in normal range (NR), according to Pressure sensor 12,13 signals are monitored to the pressure of wheel drag 18, drive braking valve for vehicle 6 to work in a left side in low pressure Position carries out ftercompction.If can not normally establish parking pressure during parking, after delay time to preset value, parking braking electricity Control unit 9 will carry out fault alarm.When driver releases parking, parking braking ECU 9 detects that park brake switch 8 is disconnected After opening, control signal is sent to braking valve for vehicle 6, driving braking valve for vehicle 6 works in right position, whole pipelines of wheel drag 18 Connected with pressure relief pipe, the release of parking pressure, release parking braking, then parking braking ECU 9 switches to traveling/parking Valve 10 sends control signal, drives to traveling/parking switching valve 10 and works in road location.

Claims (4)

  1. A kind of 1. all-wheel steering electric wheel truck line traffic control hydraulic parking braking system, it is characterised in that:Including electric hydraulic pump (2), accumulator (4) and pressure-reducing valve (5) are sequentially connected by pipeline, pressure-reducing valve (5) by pipeline respectively with braking valve for vehicle (6), manual parking valve (7) be connected, then braking valve for vehicle (6), manual parking valve (7) by pipeline respectively with traveling/parking Switching valve (10) is connected;Traveling/parking switching valve (10) is connected with the wheel drag (18) of front and back wheel respectively by pipeline;
    First pressure sensor (11) is provided with pipeline between the accumulator (4) and pressure-reducing valve (5), for monitoring accumulation of energy Device pressure, Braking system pressure is maintained in the scope of application;
    Tie point valve is provided with pipeline between the traveling/parking switching valve (10) and all the way wheel drag (18) And second pressure sensor (12) (14);Between the traveling/parking switching valve (10) and another way wheel drag (18) The second bypass valve (15) and the 3rd pressure sensor (13) are provided with pipeline;Second pressure sensor (12) and the 3rd pressure pass Sensor (13) is used to monitor wheel brake pressure, and brake pressure is in the scope of application during maintaining parking;
    The tie point valve (14), the second bypass valve (15) are dual circuit arranged crosswise branch road stop valve;
    The system is also connected including park brake switch (8) with parking braking ECU (9), parking braking ECU (9) Respectively with electric hydraulic pump (2), braking valve for vehicle (6), traveling/parking switching valve (10), first pressure sensor (11), second Pressure sensor (12), the 3rd pressure sensor (13), tie point valve (14) and the second bypass valve (15) electrical connection, it is described to stay Car brake electric control unit (9) is used to gather sensor information and controls each electric executing part.
  2. 2. brakes as claimed in claim 1, it is characterised in that:The electric hydraulic pump (2), braking valve for vehicle (6), hand Dynamic parking valve (7) is connected with brake fluid fuel tank respectively.
  3. 3. brakes as claimed in claim 1, it is characterised in that:The braking valve for vehicle (6) is that three electric-controlled hydraulics change To valve, middle position is kept for parking braking hydraulic line pressure, and other two position is released back with pressure piping and hydraulic pressure respectively Road communicates, for producing the release of parking braking and parking braking.
  4. 4. brakes as claimed in claim 1, it is characterised in that:The manual parking valve(7), under malfunction, Emergent parking braking.
CN201610227397.7A 2016-04-13 2016-04-13 A kind of all-wheel steering electric wheel truck line traffic control hydraulic parking braking system Expired - Fee Related CN105667477B (en)

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Application Number Priority Date Filing Date Title
CN201610227397.7A CN105667477B (en) 2016-04-13 2016-04-13 A kind of all-wheel steering electric wheel truck line traffic control hydraulic parking braking system

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CN201610227397.7A CN105667477B (en) 2016-04-13 2016-04-13 A kind of all-wheel steering electric wheel truck line traffic control hydraulic parking braking system

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Publication number Priority date Publication date Assignee Title
US9975529B2 (en) * 2016-08-09 2018-05-22 Ford Global Technologies, Llc Performance electric parking brake controllers
IT201600130805A1 (en) * 2016-12-23 2018-06-23 Freni Brembo Spa BRAKE-BY-WIRE AUTOMATIC BRAKING SYSTEM FOR VEHICLES
CN107244316B (en) * 2017-05-11 2019-07-23 浙江零跑科技有限公司 Vehicle automatic braking supercharging accumulator
CN108275138B (en) * 2018-03-19 2024-07-02 湖州宏威新能源汽车有限公司 Braking system and automobile
CN108482353B8 (en) * 2018-05-05 2021-01-08 吴彬 Parking brake device for vehicle
CN108501907A (en) * 2018-05-08 2018-09-07 南京理工大学 A kind of active trailer brake system
DE102018217618A1 (en) * 2018-10-15 2020-04-16 Robert Bosch Gmbh Method and device for securing a motor vehicle during an automated driving maneuver
CN110103915B (en) * 2019-05-10 2024-03-29 吉林大学青岛汽车研究院 Wet braking system with service braking, parking braking and retarding functions
CN111267808A (en) * 2020-02-27 2020-06-12 雷沃工程机械集团有限公司 Parking liquid filling system and method for loader
CN111497808B (en) * 2020-05-28 2023-06-06 武汉嘉琪新扬科技发展有限公司 Brake-by-wire system integrating parking braking and control method thereof
CN111497809B (en) * 2020-05-28 2023-11-07 武汉嘉琪新扬科技发展有限公司 Brake-by-wire system for parking brake and control method thereof
CN113619544B (en) * 2021-08-18 2022-11-04 湖南三一中型起重机械有限公司 Hydraulic brake system and working machine
CN113635966B (en) * 2021-09-06 2023-04-14 中国铁建重工集团股份有限公司 Four-wheel drive slip steering chassis hydraulic control system

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CN202753927U (en) * 2012-03-02 2013-02-27 薛德 ABS (anti-lock braking system)-based intelligent EPB (electronic parking brake) system
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EP2719588A1 (en) * 2012-10-15 2014-04-16 KNORR-BREMSE Systeme für Nutzfahrzeuge GmbH Method for operating an electrically operable parking brake system and control device of an electrically operable parking brake system
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CN205524208U (en) * 2016-04-13 2016-08-31 武汉科技大学 Electronic round of hydraulic pressure of drive -by -wire for car parking braking system of all wheel steering

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CN102785651A (en) * 2011-05-16 2012-11-21 株式会社爱德克斯 Brake control device
DE102011116906A1 (en) * 2011-10-25 2013-04-25 Wabco Gmbh Brake method and braking device for a vehicle, hydraulic brake system and vehicle with it
CN202753927U (en) * 2012-03-02 2013-02-27 薛德 ABS (anti-lock braking system)-based intelligent EPB (electronic parking brake) system
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