CN115056757B - Decoupling electrohydraulic brake with hydraulic braking force feedback - Google Patents

Decoupling electrohydraulic brake with hydraulic braking force feedback Download PDF

Info

Publication number
CN115056757B
CN115056757B CN202210907226.4A CN202210907226A CN115056757B CN 115056757 B CN115056757 B CN 115056757B CN 202210907226 A CN202210907226 A CN 202210907226A CN 115056757 B CN115056757 B CN 115056757B
Authority
CN
China
Prior art keywords
brake
cylinder
piston
feedback
braking
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.)
Active
Application number
CN202210907226.4A
Other languages
Chinese (zh)
Other versions
CN115056757A (en
Inventor
潘光显
向世水
符小军
邓伟文
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.)
Nanjing Jingweida Automobile Technology Co ltd
Original Assignee
Nanjing Jingweida Automobile Technology 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 Nanjing Jingweida Automobile Technology Co ltd filed Critical Nanjing Jingweida Automobile Technology Co ltd
Priority to CN202210907226.4A priority Critical patent/CN115056757B/en
Publication of CN115056757A publication Critical patent/CN115056757A/en
Application granted granted Critical
Publication of CN115056757B publication Critical patent/CN115056757B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60T—VEHICLE 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
    • B60T13/00—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems
    • B60T13/10—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems with fluid assistance, drive, or release
    • B60T13/12—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems with fluid assistance, drive, or release the fluid being liquid
    • B60T13/14—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems with fluid assistance, drive, or release the fluid being liquid using accumulators or reservoirs fed by pumps
    • B60T13/141—Systems with distributor valve
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60T—VEHICLE 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
    • B60T13/00—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems
    • B60T13/10—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems with fluid assistance, drive, or release
    • B60T13/66—Electrical control in fluid-pressure brake systems
    • B60T13/68—Electrical control in fluid-pressure brake systems by electrically-controlled valves
    • B60T13/686—Electrical control in fluid-pressure brake systems by electrically-controlled valves in hydraulic systems or parts thereof
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60T—VEHICLE 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
    • B60T13/00—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems
    • B60T13/74—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems with electrical assistance or drive
    • B60T13/745—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems with electrical assistance or drive acting on a hydraulic system, e.g. a master cylinder
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60T—VEHICLE 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
    • B60T7/00—Brake-action initiating means
    • B60T7/02—Brake-action initiating means for personal initiation
    • B60T7/04—Brake-action initiating means for personal initiation foot actuated
    • B60T7/042—Brake-action initiating means for personal initiation foot actuated by electrical means, e.g. using travel or force sensors
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60T—VEHICLE 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
    • B60T8/00—Arrangements for adjusting wheel-braking force to meet varying vehicular or ground-surface conditions, e.g. limiting or varying distribution of braking force
    • B60T8/32—Arrangements for adjusting wheel-braking force to meet varying vehicular or ground-surface conditions, e.g. limiting or varying distribution of braking force responsive to a speed condition, e.g. acceleration or deceleration
    • B60T8/34—Arrangements for adjusting wheel-braking force to meet varying vehicular or ground-surface conditions, e.g. limiting or varying distribution of braking force responsive to a speed condition, e.g. acceleration or deceleration having a fluid pressure regulator responsive to a speed condition
    • B60T8/40—Arrangements for adjusting wheel-braking force to meet varying vehicular or ground-surface conditions, e.g. limiting or varying distribution of braking force responsive to a speed condition, e.g. acceleration or deceleration having a fluid pressure regulator responsive to a speed condition comprising an additional fluid circuit including fluid pressurising means for modifying the pressure of the braking fluid, e.g. including wheel driven pumps for detecting a speed condition, or pumps which are controlled by means independent of the braking system
    • B60T8/4072—Systems in which a driver input signal is used as a control signal for the additional fluid circuit which is normally used for braking
    • B60T8/4081—Systems with stroke simulating devices for driver input
    • B60T8/409—Systems with stroke simulating devices for driver input characterised by details of the stroke simulating device

Abstract

The invention discloses a decoupling electrohydraulic brake with hydraulic braking force feedback, which comprises a brake master cylinder, a liquid storage tank, a motor, a gear, a rack, a pedal travel sensor, a controller, a manual cylinder piston, a manual cylinder, a braking force feedback cylinder, a simulation piston, a simulation spring, a feedback piston, a proportional pressure valve and a return spring. Compared with a vacuum booster brake and a pneumatic brake, the brake of the invention can brake according to the instruction of the whole vehicle controller when a driver does not step on the brake, and is convenient for automatic driving. Because the brake pedal and the brake master cylinder are not directly connected mechanically, the cooperative energy recovery brake is convenient. Compared with the common decoupling brake, the braking force can be directly fed back to the brake pedal during braking, and the foot feel is real during braking. Meanwhile, the feedback braking force is utilized, so that the simulation spring only needs to simulate the foot feeling when energy is recovered, the received force is small, and the design and the manufacture are easy.

Description

Decoupling electrohydraulic brake with hydraulic braking force feedback
Technical Field
The invention relates to the technical field of brakes, in particular to a decoupling electro-hydraulic brake with hydraulic braking force feedback.
Background
With the increasing requirements on energy conservation and emission reduction, more and more electric automobiles and hybrid electric automobiles are used. Both types of automobiles use motor drives. The motor has reversibility, i.e. one motor can be used as both a motor and a generator. When the automobile decelerates or descends, the motor is converted into a generator, and the kinetic energy of the automobile is converted into electric energy to be stored. In the process of generating electricity, the moment driving the generator to rotate becomes the braking moment of the automobile, so that the automobile is decelerated. The voltage of the storage battery of the automobile and the speed of the automobile can influence the braking moment when the recovered energy is used for reducing the speed of the recovered energy, so that the sufficient braking force can not be generated only by energy recovery in many times, and the mechanical brake is needed to be used for braking while the energy is recovered. The braking mode using both energy recovery and mechanical braking is called coordinated energy recovery braking, and when braking, the braking controller adjusts the braking force generated by the mechanical braking according to the braking force generated by the recovered energy, thereby recovering the energy to the maximum extent and reducing the abrasion of the mechanical brake. In order to achieve a coordinated energy recovery braking, the brake pedal and the brake cannot be directly connected, known as decoupling. In order to achieve a feel of the foot during braking, the brake generally requires a dummy cylinder, by means of which a feel of the foot is achieved.
The decoupling type brake is convenient for the cooperative energy recovery brake, but the foot feeling during the brake is completely close to the simulation cylinder and is not feedback from the braking force, so the foot feeling is not as true as the common vacuum assistance or air pressure assistance brake. The design of the simulation cylinder is troublesome because the foot feeling during braking is simulated by the spring in the simulation cylinder.
Disclosure of Invention
Aiming at the defects of the prior art, the invention aims to provide the decoupling electrohydraulic brake with hydraulic braking force feedback, which not only can realize cooperative energy recovery by utilizing decoupling, but also can feed back braking force to form foot feeling during braking, so that the foot feeling during braking is more real, and the complex design of a simulation cylinder is avoided.
In order to achieve the above purpose, the present invention adopts the following technical scheme:
a decoupling electrohydraulic brake with hydraulic braking force feedback comprises a brake master cylinder, a liquid storage tank, a motor, a gear, a rack, a pedal travel sensor, a controller, a manual cylinder piston, a manual cylinder, a braking force feedback cylinder, a simulation piston, a simulation spring, a feedback piston, a proportional pressure valve and a return spring;
the simulation piston and the feedback piston are both arranged in the braking force feedback cylinder, the feedback piston is arranged in front of the simulation piston, a baffle is arranged in front of the feedback piston, a feedback piston rod connected with the feedback piston movably forwards passes through the baffle, a rear cavity is formed between the simulation piston and the rear wall in the braking force feedback cylinder, a middle cavity is formed between the feedback piston and the baffle, and a front cavity is formed between the baffle and the front wall in the braking force feedback cylinder; a simulation spring is arranged between the feedback piston and the simulation piston, and a return spring is arranged between the feedback piston and the baffle; the opening pressure of the proportional pressure valve is controlled by the controller according to the maximum braking moment generated during the current vehicle energy recovery, and the larger the maximum braking moment generated during the energy recovery, the larger the opening pressure of the proportional pressure valve; the controller is also connected with the pedal stroke sensor and the motor in a communication way;
the gear and the rack are in meshed transmission, the motor is connected with the gear and can drive the gear to rotate, and the gear can drive the rack to move in a direction approaching to or separating from the interior of the brake master cylinder; when the rack moves to a direction close to the interior of the brake master cylinder, the brake master cylinder can be pushed to output brake fluid; the brake fluid output port of the brake master cylinder is communicated with the front cavity of the brake force feedback cylinder; the human-powered cylinder piston is arranged in the human-powered cylinder, the rear end of the human-powered cylinder piston is connected with a rear-end human-powered cylinder piston rod, and the rear-end human-powered cylinder piston rod extends out of the human-powered cylinder backwards; the rear end manual cylinder piston rod is connected with a brake pedal; the pedal travel sensor is used for measuring the travel of the brake pedal; brake fluid is filled in the manpower cylinder; the brake fluid outlet of the manpower cylinder is communicated with the rear cavity of the braking force feedback cylinder; the middle cavity of the braking force feedback cylinder is internally provided with braking fluid; the middle cavity of the braking force feedback cylinder is communicated with the inlet of the proportional pressure valve; and the outlet of the proportional pressure valve is communicated with the liquid storage tank.
Further, the front end of the manual cylinder piston is connected with a front end manual cylinder piston rod, and the front end manual piston rod and the rack are in corresponding positions and are separated by a set distance.
Further, a brake fluid inlet of the middle cavity of the braking force feedback cylinder is communicated with the liquid storage tank through a one-way valve.
Further, the simulation piston is of a U-shaped structure with an opening facing the front, one end of the simulation spring is connected to the inside of the U-shaped structure, and the other end of the simulation spring is connected to the feedback piston.
The invention also provides a working method of the decoupling electrohydraulic brake with hydraulic braking force feedback, which comprises the following specific processes:
after the vehicle is started, the controller adjusts the opening pressure of the proportional pressure valve according to the maximum braking moment generated by the energy recovery of the vehicle at the moment; when a driver steps on a brake pedal, a manual cylinder piston is pushed by a manual cylinder piston rod at the rear end, and meanwhile, a pedal stroke sensor is driven to output a pedal stroke signal, and a controller determines braking force according to the pedal stroke signal; when a driver lightly steps on a brake pedal, brake fluid in a human cylinder enters a rear cavity of a braking force feedback cylinder under the pushing of a piston of the human cylinder, and a simulation piston is pushed to compress a simulation spring; if the braking torque required at the moment is smaller than the maximum braking torque which can be generated by energy recovery, the pressure of the braking fluid in the middle cavity is smaller than the opening pressure of the proportional pressure valve, so that the feedback piston cannot be pushed, the simulation piston is pushed by the generated reaction force due to the fact that the simulation spring is compressed, and then the braking fluid in the rear cavity pushes the manual cylinder piston to form a braking foot feeling; at the moment, the braking force is generated completely by the recovered energy, the motor does not work, and the brake master cylinder does not output hydraulic pressure;
when the speed of the automobile is too low or the storage battery is full, the vehicle has no energy recovery capacity at this time, so that the braking force is generated completely by the mechanical brake; the controller adjusts the opening pressure of the proportional pressure valve to 0, when a driver presses a brake pedal, the simulation piston is pushed forward, and as the opening pressure of the proportional pressure valve is 0, the feedback piston is pushed, and brake fluid in the middle cavity flows back to the liquid storage tank through the proportional pressure valve; the controller drives the motor according to a pedal stroke signal of the pedal stroke sensor, and the motor pushes the brake master cylinder to output brake hydraulic pressure through the gear and the rack; and part of the output high-pressure brake fluid enters a front cavity of the braking force feedback cylinder, the feedback piston is pushed to form feedback force by pushing the feedback piston rod, the feedback force is transmitted to the simulation piston through the simulation spring, and the simulation piston transmits the feedback force to the human force cylinder piston through the brake fluid of the rear cavity to form braking foot feeling.
Further, when the automobile has energy recovery capability and a driver presses a brake pedal to brake at a large force, the controller adjusts the opening pressure of the proportional pressure valve according to the maximum braking moment generated by energy recovery; because of the large-force braking, the required braking force is large, at the moment, the braking hydraulic pressure of the middle cavity of the braking force feedback cylinder is larger than the opening pressure of the proportional pressure valve, and then the redundant braking liquid in the middle cavity pushes up the proportional pressure valve to flow back to the liquid storage tank, and the feedback piston is pushed forward; the pressure of the brake fluid in the middle cavity is equal to the opening pressure of the proportional pressure valve, and a force is generated on the feedback piston, and the force is proportional to the brake moment generated by the recovered energy; because the driver brakes with great force at this moment, the braking moment produced by the recovered energy is insufficient, so the controller controls the motor to rotate, and the gear and the rack push the brake master cylinder to output the braking hydraulic pressure to the brake cylinder to produce the braking moment; at the moment, the brake fluid output by the brake master cylinder flows into the front cavity of the brake force feedback cylinder to push the feedback piston to feedback the hydraulic pressure during braking; at this time, the force received by the feedback piston is equal to the force generated by the brake fluid in the middle cavity plus the force generated by the hydraulic pressure in the front cavity, and the force received by the feedback piston is transmitted to the brake pedal through the simulation piston and the manual cylinder piston in sequence, so that a brake foot feeling is formed.
Further, when the motor fails, the controller adjusts the opening pressure of the proportional pressure valve to 0, and when the driver presses the brake pedal, the brake fluid in the middle cavity of the braking force feedback cylinder flows back to the fluid reservoir because the opening pressure of the proportional pressure valve is 0; the front end piston rod of the manual cylinder piston is driven by the manual piston cylinder to move forward to be in contact with the rack and generate pushing force to the rack, so that the brake master cylinder is pushed to output hydraulic pressure to the brake cylinder, and manual braking is formed.
Further, when a driver releases the brake pedal, the return spring pushes the feedback piston back to the original position, and brake fluid flows into the middle cavity of the braking force feedback cylinder from the liquid storage tank through the one-way valve; the simulation spring pushes the simulation piston back to the original position, the simulation piston pushes the piston of the manpower cylinder back through the brake fluid, and the brake fluid flows into the manpower cylinder again.
The invention has the beneficial effects that: compared with a vacuum booster brake and a pneumatic brake, the brake of the invention can brake according to the instruction of the whole vehicle controller when a driver does not step on the brake, and is convenient for automatic driving. Because the brake pedal and the brake master cylinder are not directly connected mechanically, the cooperative energy recovery brake is convenient. Compared with the common decoupling brake, the braking force can be directly fed back to the brake pedal during braking, and the foot feel is real during braking. Meanwhile, the feedback braking force is utilized, so that the simulation spring only needs to simulate the foot feeling when energy is recovered, the received force is small, and the design and the manufacture are easy.
Drawings
Fig. 1 is a schematic diagram of a normal structure of a decoupling electro-hydraulic brake in embodiment 1 of the present invention;
FIG. 2 is a schematic structural view of the braking force feedback cylinder of FIG. 1;
FIG. 3 is a schematic diagram showing the operation of the decoupling electro-hydraulic brake in the case of the braking force being generated entirely by recovered energy in embodiment 2 of the present invention;
FIG. 4 is a schematic structural view of the braking force feedback cylinder of FIG. 3;
FIG. 5 is a schematic diagram illustrating the operation of the decoupling electro-hydraulic brake in example 2 of the present invention with no energy recovery capability of the vehicle;
FIG. 6 is a schematic structural view of the braking force feedback cylinder of FIG. 5;
FIG. 7 is a schematic diagram showing the operation of the decoupling electro-hydraulic brake in the case of the vehicle according to embodiment 2 of the present invention when the vehicle has energy recovery capability and the driver depresses the brake pedal with a large force;
FIG. 8 is a schematic structural view of the brake force feedback cylinder of FIG. 7;
FIG. 9 is a schematic diagram showing the operation of the decoupling electro-hydraulic brake in the event of a motor failure in embodiment 2 of the present invention;
fig. 10 is a schematic operation diagram of the decoupling electro-hydraulic brake in case that the driver releases the brake pedal in embodiment 2 of the present invention.
Detailed Description
The present invention will be further described with reference to the accompanying drawings, and it should be noted that, while the present embodiment provides a detailed implementation and a specific operation process on the premise of the present technical solution, the protection scope of the present invention is not limited to the present embodiment.
Example 1
The embodiment provides a decoupling type electrohydraulic brake with hydraulic braking force feedback, which comprises a brake master cylinder 1, a liquid storage tank 2, a motor 3, a gear 4, a rack 5, a pedal stroke sensor 6, a controller 7, a manual cylinder piston 8, a manual cylinder 9, a braking force feedback cylinder 10, a simulation piston 11, a simulation spring 12, a feedback piston 13, a proportional pressure valve 15 and a return spring 16, as shown in fig. 1.
The simulation piston 11 and the feedback piston 13 are both arranged in the braking force feedback cylinder 10, the feedback piston 13 is arranged in front of the simulation piston 11, a baffle 17 is arranged in front of the feedback piston 13, a feedback piston rod 18 connected with the feedback piston 13 movably passes through the baffle 17 forwards, a rear cavity 19 is formed between the simulation piston 11 and the rear wall inside the braking force feedback cylinder 10, a middle cavity 20 is formed between the feedback piston 13 and the baffle 17, and a front cavity 21 is formed between the baffle 17 and the front wall inside the braking force feedback cylinder 10, as shown in fig. 2; a simulation spring 12 is arranged between the feedback piston 13 and the simulation piston 11, and a return spring 16 is arranged between the feedback piston 13 and the baffle 17; the opening pressure of the proportional pressure valve 15 is controlled by the controller 7 according to the maximum braking torque generated when the current vehicle energy is recovered, and the larger the maximum braking torque which can be generated by the energy recovery is, the larger the opening pressure of the proportional pressure valve 15 is; the controller 7 is also communicatively connected to the pedal travel sensor 6 and the motor 3;
the gear 4 and the rack 5 are in meshed transmission, the motor 3 is connected with the gear 4 and can drive the gear 4 to rotate, and the gear 4 can drive the rack 5 to move towards or away from the interior of the brake master cylinder 1; when the rack 5 moves to a direction approaching the interior of the brake master cylinder 1, the brake master cylinder 1 can be pushed to output brake fluid; the brake fluid output port of the brake master cylinder 1 is communicated with the front cavity 21 of the braking force feedback cylinder 10; the human-powered cylinder piston 8 is arranged in the human-powered cylinder 9, the rear end of the human-powered cylinder piston 8 is connected with a rear-end human-powered cylinder piston rod 22, and the rear-end human-powered cylinder piston rod 22 extends out of the human-powered cylinder 9 backwards; the rear-end manual cylinder piston rod 22 is connected with a brake pedal; the pedal stroke sensor 6 is used for measuring the stroke of the brake pedal; brake fluid is filled in the manual cylinder 9; the brake fluid outlet of the manual cylinder 9 is communicated with the rear cavity 19 of the braking force feedback cylinder 10; the braking fluid is filled in the middle cavity 20 of the braking force feedback cylinder 10; the middle cavity 20 of the braking force feedback cylinder 10 is communicated with the inlet of the proportional pressure valve 15; the outlet of the proportional pressure valve 15 is communicated with the liquid storage tank 2.
In this embodiment, a front end human piston rod 23 is connected to the front end of the human piston 8, and the front end human piston rod 23 and the rack 5 are located at a set distance. When the motor 3 fails, the front-end manual piston rod 23 can be used for driving the rack 5, so that manual braking is realized.
In this embodiment, the brake fluid inlet of the middle chamber of the brake force feedback cylinder 10 is connected to the reservoir tank 2 through a check valve 14.
In this embodiment, the dummy piston 11 has a U-shaped structure with an opening facing the front, and one end of the dummy spring 12 is connected to the inside of the U-shaped structure, and the other end is connected to the feedback piston 13. When the feedback force generated by the feedback piston 13 is too large, the front end surface of the simulation piston 11 will come into contact with the feedback piston 13 before the simulation spring 12 is fully compressed, so that the excessive stress of the simulation spring 12 can be avoided.
Example 2
The embodiment provides a working method of the decoupling electro-hydraulic brake with hydraulic braking force feedback according to embodiment 1, which specifically comprises the following steps:
after the vehicle is started, the controller 7 adjusts the opening pressure of the proportional pressure valve 15 according to the maximum braking torque which can be generated by the energy recovery of the vehicle at the moment; when a driver presses a brake pedal, the rear-end manual cylinder piston rod 22 pushes the manual cylinder piston 8, and meanwhile, the pedal stroke sensor 6 is driven to output a pedal stroke signal, and the controller 7 determines braking force according to the pedal stroke signal. When a driver lightly steps on a brake pedal, brake fluid in a human cylinder 9 enters a rear cavity of a braking force feedback cylinder 10 under the pushing of a human cylinder piston 8, a simulation piston 11 is pushed, and a simulation spring 12 is compressed; if the braking torque required at this time is smaller than the maximum braking torque which can be generated by energy recovery, the pressure of the braking fluid in the middle cavity is smaller than the opening pressure of the proportional pressure valve 15, so that the feedback piston 13 cannot be pushed, the simulation piston 11 is pushed by the generated reaction force due to the compression of the simulation spring 12, and the manual cylinder piston 8 is pushed by the braking fluid in the rear cavity to form a braking foot feeling, as shown in fig. 3 and 4. At this time, the braking force is generated entirely by the recovered energy, the motor 3 does not operate, and the master cylinder 1 does not output the hydraulic pressure.
When the vehicle speed is too low, or the battery has been full, the vehicle has no energy recovery capacity and therefore the braking force is generated entirely by the mechanical brake. At this time, the controller 7 adjusts the opening pressure of the proportional pressure valve 15 to 0, and when the driver depresses the brake pedal, the dummy piston 11 is pushed forward, and since the opening pressure of the proportional pressure valve 15 is 0, the feedback piston 13 is pushed, and the brake fluid in the intermediate chamber flows back to the reservoir tank 2 through the proportional pressure valve 15. The controller 7 drives the motor 3 according to a pedal stroke signal of the pedal stroke sensor 6, and the motor 3 pushes the master cylinder 1 through the gear 4 and the rack 5 to output brake fluid pressure. Part of the output high-pressure brake fluid enters a front cavity of the braking force feedback cylinder 10, the feedback piston 13 is pushed to form feedback force by pushing the feedback piston rod, the feedback force is transmitted to the simulation piston 11 through the simulation spring 12 by the feedback piston 13, and the simulation piston 11 transmits the feedback force to the human force cylinder piston 8 through brake fluid of a rear cavity to form brake foot feeling.
In this embodiment, when the feedback force is large, the dummy piston 11 and the feedback piston 13 are in direct contact so that the dummy spring 12 is not subjected to excessive pressure, as shown in fig. 5 and 6.
When the vehicle has energy recovery capability and the driver presses the brake pedal to brake at a high force, the controller 7 adjusts the opening pressure of the proportional pressure valve 15 according to the maximum braking torque generated by the energy recovery capability. Because of the large braking force, the braking force is large, at this time, the braking force pressure in the middle cavity of the braking force feedback cylinder 10 is larger than the opening pressure of the proportional pressure valve 15, so that the excessive braking liquid in the middle cavity 20 pushes the proportional pressure valve 15 back to the liquid storage tank 2, and the feedback piston 13 is pushed forward. The pressure of the brake fluid in the intermediate chamber is now equal to the opening pressure of the proportional pressure valve 15 and generates a force to the feedback piston 13 that is proportional to the braking torque generated by the recovered energy. Because the driver brakes with great force at this time, the braking moment generated by the recovered energy is insufficient, and then the controller 7 controls the motor 3 to rotate, and pushes the brake master cylinder 1 to output the braking hydraulic pressure to the wheel cylinders through the gear 4 and the rack 5 to generate the braking moment. At this time, the brake fluid output from the master cylinder 1 flows into the front chamber of the brake force feedback cylinder 10, pushing the feedback piston 13 to generate hydraulic force for feedback braking, as shown in fig. 7 and 8. At this time, the force received by the feedback piston 13 is equal to the force generated by the brake fluid in the middle cavity plus the force generated by the hydraulic pressure in the front cavity, and the force received by the feedback piston 13 is transmitted to the brake pedal through the simulation piston 11 and the manual cylinder piston 8 in sequence, so that a brake foot feeling is formed.
When the motor 3 fails, the controller 7 adjusts the opening pressure of the proportional pressure valve 15 to 0 at this time, and the driver depresses the brake pedal, and the brake fluid in the middle chamber of the brake force feedback cylinder 10 returns to the reservoir tank 2 because the opening pressure of the proportional pressure valve 15 is 0. The front end piston rod of the manual cylinder piston 8 is driven by the manual piston cylinder 8 to move forward to be in contact with the rack 5 and generate pushing force on the rack, so that the master cylinder 1 is pushed to output hydraulic pressure to the brake cylinder, and manual braking is formed, as shown in fig. 9.
When the driver releases the brake pedal, the return spring 16 pushes the feedback piston 13 back into position, and brake fluid flows from the reservoir 2 through the check valve 14 into the middle chamber of the brake force feedback cylinder 10. The dummy piston 11 is pushed back by the dummy spring 12, the dummy piston 11 pushes back the manual cylinder piston 8 by the brake fluid, and the brake fluid flows back into the manual cylinder 9. As shown in fig. 10.
Various modifications and variations of the present invention will be apparent to those skilled in the art in light of the foregoing teachings and are intended to be included within the scope of the following claims.

Claims (8)

1. The decoupling electrohydraulic brake with the hydraulic braking force feedback is characterized by comprising a brake master cylinder, a liquid storage tank, a motor, a gear, a rack, a pedal travel sensor, a controller, a manual cylinder piston, a manual cylinder, a braking force feedback cylinder, a simulation piston, a simulation spring, a feedback piston, a proportional pressure valve and a return spring;
the simulation piston and the feedback piston are both arranged in the braking force feedback cylinder, the feedback piston is arranged in front of the simulation piston, a baffle is arranged in front of the feedback piston, a feedback piston rod connected with the feedback piston movably forwards passes through the baffle, a rear cavity is formed between the simulation piston and the rear wall in the braking force feedback cylinder, a middle cavity is formed between the feedback piston and the baffle, and a front cavity is formed between the baffle and the front wall in the braking force feedback cylinder; a simulation spring is arranged between the feedback piston and the simulation piston, and a return spring is arranged between the feedback piston and the baffle; the opening pressure of the proportional pressure valve is controlled by the controller according to the maximum braking moment generated during the current vehicle energy recovery, and the larger the maximum braking moment generated during the energy recovery, the larger the opening pressure of the proportional pressure valve; the controller is also connected with the pedal stroke sensor and the motor in a communication way;
the gear and the rack are in meshed transmission, the motor is connected with the gear and can drive the gear to rotate, and the gear can drive the rack to move in a direction approaching to or separating from the interior of the brake master cylinder; when the rack moves to a direction close to the interior of the brake master cylinder, the brake master cylinder can be pushed to output brake fluid; the brake fluid output port of the brake master cylinder is communicated with the front cavity of the brake force feedback cylinder; the human-powered cylinder piston is arranged in the human-powered cylinder, the rear end of the human-powered cylinder piston is connected with a rear-end human-powered cylinder piston rod, and the rear-end human-powered cylinder piston rod extends out of the human-powered cylinder backwards; the rear end manual cylinder piston rod is connected with a brake pedal; the pedal travel sensor is used for measuring the travel of the brake pedal; brake fluid is filled in the manpower cylinder; the brake fluid outlet of the manpower cylinder is communicated with the rear cavity of the braking force feedback cylinder; the middle cavity of the braking force feedback cylinder is internally provided with braking fluid; the middle cavity of the braking force feedback cylinder is communicated with the inlet of the proportional pressure valve; and the outlet of the proportional pressure valve is communicated with the liquid storage tank.
2. The decoupled electro-hydraulic brake of claim 1, wherein a front end of the master cylinder piston is coupled with a front end master cylinder piston rod, the front end master cylinder piston rod and the rack being in position correspondence and a set distance apart.
3. The decoupled electro-hydraulic brake of claim 1, wherein the brake fluid inlet of the middle chamber of the brake force feedback cylinder is in communication with the reservoir via a one-way valve.
4. The decoupling electro-hydraulic brake of claim 1, wherein the dummy piston has a U-shaped structure with an opening facing forward, and one end of the dummy spring is connected to the inside of the U-shaped structure, and the other end is connected to the feedback piston.
5. A method of operating a decoupled electro-hydraulic brake with hydraulic brake force feedback as defined in claim 1, comprising the steps of:
after the vehicle is started, the controller adjusts the opening pressure of the proportional pressure valve according to the maximum braking moment generated by the energy recovery of the vehicle at the moment; when a driver steps on a brake pedal, a piston rod of a human cylinder at the rear end pushes the piston of the human cylinder, and meanwhile, a pedal stroke sensor is driven to output a pedal stroke signal, and a controller determines braking force according to the pedal stroke signal; when a driver lightly steps on a brake pedal, brake fluid in a human cylinder enters a rear cavity of a braking force feedback cylinder under the pushing of a piston of the human cylinder, and a simulation piston is pushed to compress a simulation spring; if the braking torque required at the moment is smaller than the maximum braking torque which can be generated by energy recovery, the pressure of the braking fluid in the middle cavity is smaller than the opening pressure of the proportional pressure valve, so that the feedback piston cannot be pushed, the simulation piston is pushed by the generated reaction force due to the fact that the simulation spring is compressed, and then the braking fluid in the rear cavity pushes the manual cylinder piston to form a braking foot feeling; at the moment, the braking force is generated completely by the recovered energy, the motor does not work, and the brake master cylinder does not output hydraulic pressure;
when the vehicle speed is too low, or the battery has been full, the vehicle has no energy recovery capacity at this time, so the braking force is generated entirely by the mechanical brake; the controller adjusts the opening pressure of the proportional pressure valve to 0, when a driver presses a brake pedal, the simulation piston is pushed forward, and as the opening pressure of the proportional pressure valve is 0, the feedback piston is pushed, and brake fluid in the middle cavity flows back to the liquid storage tank through the proportional pressure valve; the controller drives the motor according to a pedal stroke signal of the pedal stroke sensor, and the motor pushes the brake master cylinder to output brake hydraulic pressure through the gear and the rack; and part of the output high-pressure brake fluid enters a front cavity of the braking force feedback cylinder, the feedback piston is pushed to form feedback force by pushing the feedback piston rod, the feedback force is transmitted to the simulation piston through the simulation spring, and the simulation piston transmits the feedback force to the human force cylinder piston through the brake fluid of the rear cavity to form braking foot feeling.
6. The method of claim 5, wherein the controller adjusts the opening pressure of the proportional pressure valve based on a maximum braking torque that can be generated by the recuperation when the vehicle has the recuperation capability while the driver is pressing the brake pedal to brake with high force; because of the large-force braking, the required braking force is large, at the moment, the braking hydraulic pressure of the middle cavity of the braking force feedback cylinder is larger than the opening pressure of the proportional pressure valve, and then the redundant braking liquid in the middle cavity pushes up the proportional pressure valve to flow back to the liquid storage tank, and the feedback piston is pushed forward; the pressure of the brake fluid in the middle cavity is equal to the opening pressure of the proportional pressure valve, and a force is generated on the feedback piston, and the force is proportional to the brake moment generated by the recovered energy; because the driver brakes with great force at this moment, the braking moment produced by the recovered energy is insufficient, so the controller controls the motor to rotate, and the gear and the rack push the brake master cylinder to output the braking hydraulic pressure to the brake cylinder to produce the braking moment; at the moment, the brake fluid output by the brake master cylinder flows into the front cavity of the brake force feedback cylinder to push the feedback piston to feedback the hydraulic pressure during braking; at this time, the force received by the feedback piston is equal to the force generated by the brake fluid in the middle cavity plus the force generated by the hydraulic pressure in the front cavity, and the force received by the feedback piston is transmitted to the brake pedal through the simulation piston and the manual cylinder piston in sequence, so that a brake foot feeling is formed.
7. The working method according to claim 5, wherein the front end of the human cylinder piston is connected with a front-end human cylinder piston rod, and the front-end human cylinder piston rod and the rack are in corresponding positions and are separated by a set distance; when the motor fails, the controller adjusts the opening pressure of the proportional pressure valve to 0, and a driver presses a brake pedal at the moment, and as the opening pressure of the proportional pressure valve is 0, the brake fluid in the middle cavity of the braking force feedback cylinder flows back to the fluid reservoir; the front end manpower cylinder piston rod is driven by the manpower cylinder piston to move forward to be in contact with the rack and generate pushing force to the rack, so that the master cylinder is pushed to output hydraulic pressure to the brake cylinder, and the manpower brake is formed.
8. The working method according to claim 5, wherein the brake fluid inlet of the middle cavity of the brake force feedback cylinder is communicated with the reservoir through a one-way valve; when a driver releases a brake pedal, the return spring pushes the feedback piston back to the original position, and brake fluid flows into a middle cavity of the braking force feedback cylinder from the liquid storage tank through the one-way valve; the simulation spring pushes the simulation piston back to the original position, the simulation piston pushes the piston of the manpower cylinder back through the brake fluid, and the brake fluid flows into the manpower cylinder again.
CN202210907226.4A 2022-07-29 2022-07-29 Decoupling electrohydraulic brake with hydraulic braking force feedback Active CN115056757B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202210907226.4A CN115056757B (en) 2022-07-29 2022-07-29 Decoupling electrohydraulic brake with hydraulic braking force feedback

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202210907226.4A CN115056757B (en) 2022-07-29 2022-07-29 Decoupling electrohydraulic brake with hydraulic braking force feedback

Publications (2)

Publication Number Publication Date
CN115056757A CN115056757A (en) 2022-09-16
CN115056757B true CN115056757B (en) 2024-02-02

Family

ID=83208289

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202210907226.4A Active CN115056757B (en) 2022-07-29 2022-07-29 Decoupling electrohydraulic brake with hydraulic braking force feedback

Country Status (1)

Country Link
CN (1) CN115056757B (en)

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH1044952A (en) * 1996-07-31 1998-02-17 Aisin Seiki Co Ltd Brake controller for electric motor vehicle
CN101982356A (en) * 2010-11-14 2011-03-02 江苏技术师范学院 Automobile brake pedal mechanism and pedal feel simulator thereof
CN103552557A (en) * 2013-11-18 2014-02-05 扬州泰博汽车电子智能科技有限公司 Electro-hydraulic composite braking system with electric braking assistant force and brake-by-wire function
CN104309599A (en) * 2014-09-26 2015-01-28 同济大学 Electro-hydraulic brake system
CN209051412U (en) * 2018-10-28 2019-07-02 华东交通大学 A kind of electronic hydraulic brake system with good simulation pedal force feeling
KR20190096146A (en) * 2018-02-08 2019-08-19 주식회사 만도 Electric brake system

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH1044952A (en) * 1996-07-31 1998-02-17 Aisin Seiki Co Ltd Brake controller for electric motor vehicle
CN101982356A (en) * 2010-11-14 2011-03-02 江苏技术师范学院 Automobile brake pedal mechanism and pedal feel simulator thereof
CN103552557A (en) * 2013-11-18 2014-02-05 扬州泰博汽车电子智能科技有限公司 Electro-hydraulic composite braking system with electric braking assistant force and brake-by-wire function
CN104309599A (en) * 2014-09-26 2015-01-28 同济大学 Electro-hydraulic brake system
KR20190096146A (en) * 2018-02-08 2019-08-19 주식회사 만도 Electric brake system
CN209051412U (en) * 2018-10-28 2019-07-02 华东交通大学 A kind of electronic hydraulic brake system with good simulation pedal force feeling

Also Published As

Publication number Publication date
CN115056757A (en) 2022-09-16

Similar Documents

Publication Publication Date Title
CN106891878B (en) Motor-driven electronic hydraulic brake system with improved master cylinder
CN109177944B (en) Hydraulically-coupled electronic hydraulic brake system
CN105667485B (en) A kind of energy assisted braking system for automobile
CN105774788A (en) Electric power-assisted braking system with composite functions
JP5386042B2 (en) Brake device for vehicle and control method for vehicle brake device
CN104760586A (en) Double-motor driving type electronic hydraulic brake system capable of actively simulating pedal feeling
CN107697053B (en) A kind of recycling of braking energy of electric automobiles and reutilization system
CN108501921A (en) A kind of hydraulic pressure line control brake system and its brake control method with double pressure sources
CN104943672A (en) Hydraulic brake system and method with double hydraulic cylinder four-wheel failure backup
CN104309597A (en) Control method for hydraulic dual motor-driven electronic hydraulic braking system
CN103950443A (en) Pedal feeding active control type electronic hydraulic braking system
CN110774900B (en) Full-decoupling regenerative braking device for hub motor driven automobile and control method
CN108216174A (en) A kind of dual active boost braking system of redundance type
CN112896124A (en) Power assisting system and braking method
CN201442578U (en) Vacuum servo braking system of electric automobile
CN104129382A (en) Vacuum booster capable of simulating pedal travel
CN110696798A (en) Electronic hydraulic braking system and method applied to large-tonnage vehicle and large-tonnage vehicle
CN115056757B (en) Decoupling electrohydraulic brake with hydraulic braking force feedback
CN202716864U (en) Integrated hydraulic unit of automobile braking system
CN108248592A (en) Electric-machine directly-driven line control brake system and its brake control method with master/slave cylinder
CN211809554U (en) Integrated braking system with adjustable pedal feel
CN113492817A (en) Vehicle braking system and vehicle
CN216424375U (en) Novel electronic hydraulic power assisting device
CN102795216A (en) Hydraulic unit for integrated automobile brake system
CN101508286A (en) Brake booster for electric motor

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant