Brake-by-wire system and brake-by-wire method
阅读说明：本技术 线控制动系统及线控制动方法 (Brake-by-wire system and brake-by-wire method ) 是由 曹标 朱挺 张博 赵鑫 于 2020-05-13 设计创作，主要内容包括：本发明提供一种线控制动系统及线控制动方法,其中,系统包括：制动踏板模块、液压模块、制动执行模块和控制模块,制动执行模块包括用于制动驱动轮的盘式电子机械制动器、用于制动从动轮的组合式电子机械制动器,以及用于制动后轮的鼓式液压制动器。当电子机械制动器能够正常工作时,控制模块能够继续控制盘式电子机械制动器和组合式电子机械制动器对车辆进行制动；当电子机械制动器失效时,控制模块能够控制鼓式液压制动器对车辆进行制动。由此,即使是车辆的电子机械制动器失效,仍能够通过鼓式液压制动器对车辆进行制动。避免了因车辆的电子机械制动器失效而造成的无法制动车辆的问题,提高了车辆的安全性。(The invention provides a line control brake system and a line control brake method, wherein the system comprises: the brake system comprises a brake pedal module, a hydraulic module, a brake execution module and a control module, wherein the brake execution module comprises a disc type electronic mechanical brake for braking a driving wheel, a combined type electronic mechanical brake for braking a driven wheel and a drum type hydraulic brake for braking a rear wheel. When the electronic mechanical brake can work normally, the control module can continue to control the disc type electronic mechanical brake and the combined type electronic mechanical brake to brake the vehicle; when the electronic mechanical brake fails, the control module can control the drum type hydraulic brake to brake the vehicle. Thus, even if the electromechanical brake of the vehicle fails, the vehicle can be braked by the drum type hydraulic brake. The problem that the vehicle cannot be braked due to failure of an electronic mechanical brake of the vehicle is avoided, and the safety of the vehicle is improved.)
1. A line control actuator system, comprising:
a brake pedal module for providing mechanical energy to the brake-by-wire system;
the hydraulic module is connected with the brake pedal module so as to convert the mechanical energy input by the brake pedal module into hydraulic energy;
the brake execution module is connected with the hydraulic module so that brake fluid of the hydraulic module pushes the brake execution module to brake a vehicle; the brake execution module comprises a disc type electronic mechanical brake for braking the driving wheel, a combined type electronic mechanical brake for braking the driven wheel and a drum type hydraulic brake for braking the rear wheel;
the control module is respectively connected with the brake pedal module, the hydraulic module and the brake execution module, when the disc type electronic mechanical brake and the combined type electronic mechanical brake of the brake execution module are in a normal working state, the control module closes a hydraulic pipeline of the hydraulic module according to state information when the disc type electronic mechanical brake and the combined type electronic mechanical brake are in the normal working state, and simultaneously opens a brake oil can of the hydraulic module, so that the brake pedal module pushes the brake fluid to flow into the brake oil can, and the vehicle is continuously braked by the disc type electronic mechanical brake and the combined type electronic mechanical brake; or
When the disc type electronic mechanical brake and the combined type electronic mechanical brake of the brake execution module are in an abnormal working state, the control module opens the hydraulic pipeline of the hydraulic module according to state information when the disc type electronic mechanical brake and the combined type electronic mechanical brake are in the abnormal working state, and simultaneously closes the brake oil can of the hydraulic module, so that the brake pedal module pushes the brake fluid to flow into the hydraulic pipeline, and a vehicle is braked through the drum type hydraulic brake;
wherein the hydraulic line is used for delivering the brake fluid to the drum brake.
2. The brake-by-wire system of claim 1, wherein the brake pedal module comprises a brake pedal and a booster, the brake pedal being coupled to the booster to transfer pressure experienced by the brake pedal to the booster and generate the mechanical energy, the booster being coupled to the hydraulic module to transfer the mechanical energy to the hydraulic module.
3. The brake-by-wire system of claim 2, wherein the hydraulic module comprises a first solenoid valve, a second solenoid valve, a hydraulic line, a brake oil can, and a master cylinder;
the first electromagnetic valve is respectively connected with the control module and the brake oil can so as to control the brake oil can to be opened or closed according to the state information, received by the control module, of the disc type electromechanical brake and the combined type electromechanical brake in the normal working state or the abnormal working state;
the second electromagnetic valve is respectively connected with the control module and the hydraulic pipeline so as to control the hydraulic pipeline to be closed or opened according to the state information, received by the control module, of the disc type electronic mechanical brake and the combined type electronic mechanical brake in the normal working state or the abnormal working state;
one side of the brake master cylinder is connected with the power assisting device so as to convert mechanical energy input by the brake pedal module into hydraulic energy; the other side of the brake master cylinder is connected with the hydraulic pipeline so as to push the brake fluid to flow into the hydraulic pipeline by using the hydraulic energy and brake the vehicle by the drum type hydraulic brake.
4. The brake-by-wire system of claim 3, wherein the first solenoid valve and the second solenoid valve are both normally closed solenoid valves.
5. The brake-by-wire system of claim 2, wherein the control module controls the disc electromechanical brake and the combination electromechanical brake to brake the vehicle according to a relationship of a pedal stroke of the brake pedal and a braking deceleration.
6. The brake-by-wire system according to any one of claims 1 to 5, wherein the control module comprises an electronic control unit and a vehicle body electronic stabilization system, the electronic control unit continues to control the disc electromechanical brake and the combined electromechanical brake to brake the vehicle according to the state information when the disc electromechanical brake and the combined electromechanical brake are in the normal operating state; and the electronic vehicle body stabilizing system controls the drum type hydraulic brake to brake the vehicle according to the state information of the disc type electronic mechanical brake and the combined type electronic mechanical brake in the abnormal working state.
7. A brake-by-wire method, characterized in that, with the brake-by-wire system according to any one of claims 1 to 6, the brake-by-wire method comprises:
judging whether the disc type electronic mechanical brake and the combined type electronic mechanical brake of the brake execution module brake normally;
if the braking state is normal, the vehicle is continuously braked by the disc type electronic mechanical brake and the combined type electronic mechanical brake;
and if the brake is abnormal, braking the vehicle by the drum type hydraulic brake of the brake execution module.
8. The brake-by-wire method of claim 7, wherein when the control module includes an electronic control unit and a body electronic stability system, said continuing to brake the vehicle with the disc electromechanical brake and the combination electromechanical brake comprises:
the electronic control unit controls a second electromagnetic valve to close a hydraulic pipeline of the hydraulic module according to state information when the disc type electronic mechanical brake and the combined type electronic mechanical brake are in a normal working state;
meanwhile, the electronic control unit controls a first electromagnetic valve to open a brake oil can of the hydraulic module according to state information when the disc type electronic mechanical brake and the combined type electronic mechanical brake are in a normal working state;
the brake pedal module pushes the brake fluid of the hydraulic module to flow into the brake oil can;
the calipers of the disc electromechanical brake and the combined electromechanical brake apply clamping force to vehicle tires according to control information of the electronic control unit to brake the vehicle.
9. The brake-by-wire method according to claim 8, wherein the braking of the vehicle by the drum brake hydraulic of the brake actuation module includes:
the electronic vehicle body stabilizing system controls a hydraulic pipeline of the second electromagnetic valve opening hydraulic module according to state information when the disc type electronic mechanical brake and the combined type electronic mechanical brake are in an abnormal working state;
meanwhile, the vehicle body electronic stabilization system controls the first electromagnetic valve to close a brake oil can of the hydraulic module according to state information when the disc type electronic mechanical brake and the combined type electronic mechanical brake are in an abnormal working state;
the brake pedal module pushes the brake fluid of the hydraulic module to flow into the hydraulic pipeline, so that the brake fluid pushes the drum type hydraulic brake to brake the vehicle.
Technical Field
The invention relates to the technical field of vehicle control, in particular to a brake-by-wire system and a brake-by-wire method.
Background
With the increasing popularity of vehicles, people have higher and higher requirements on the braking performance of the braking system of the vehicle, and particularly, the concepts of intelligent vehicles and unmanned vehicles are rolled around the world.
In order to better achieve the braking of vehicles, brake-by-wire systems are increasingly becoming an indispensable part of the automotive industry. The brake-by-wire system is an electronic control brake system, and an electric unit directly drives a piston without oil pressure conversion, so that the more direct management of an 'electric' signal on the brake system is directly realized.
The brake-by-wire system is classified into a hydraulic brake-by-wire system (EHB) and a mechanical brake-by-wire system (EMB). The hydraulic brake-by-wire system combines an electronic system and a hydraulic system. The hydraulic control system mainly comprises an electronic pedal, an Electronic Control Unit (ECU) and a hydraulic actuating mechanism. The electronic pedal is composed of a brake pedal and a pedal sensor (pedal displacement sensor). The pedal sensor is used for detecting pedal travel, and then converting displacement signals into electric signals to be transmitted to the ECU, so that the pedal travel and braking force are regulated and controlled in proportion. The mechanical brake-by-wire system does not require a hydraulic brake line. The driver steps on the electronic pedal, and the displacement sensor sends the signal to ECU, and ECU promotes the braking cylinder body to the vehicle braking through the operation of control mechanical structure.
However, when the mechanical brake-by-wire system fails, the driver cannot operate the mechanical structure to cause deceleration of the vehicle. This may affect the safety performance of the vehicle.
Disclosure of Invention
The invention aims to solve the problem that when a mechanical brake-by-wire system in the prior art fails, a driver cannot operate a mechanical structure to enable a vehicle to generate deceleration, so that the safety performance of the vehicle is influenced.
In order to solve the above problems, embodiments of the present invention disclose a brake-by-wire system and a brake-by-wire method, in which when a mechanical brake-by-wire system fails, a vehicle can still generate deceleration, thereby improving the safety performance of the vehicle.
The embodiment of the invention discloses a line control actuating system, which comprises: the brake pedal module is used for providing mechanical energy for the brake-by-wire system;
the hydraulic module is connected with the brake pedal module so as to convert the mechanical energy input by the brake pedal module into hydraulic energy;
the brake execution module is connected with the hydraulic module so that the brake fluid of the hydraulic module pushes the brake execution module to brake the vehicle; the brake execution module comprises a disc type electronic mechanical brake for braking the driving wheel, a combined type electronic mechanical brake for braking the driven wheel and a drum type hydraulic brake for braking the rear wheel;
the control module is respectively connected with the brake pedal module, the hydraulic module and the brake execution module, when the disc type electronic mechanical brake and the combined type electronic mechanical brake of the brake execution module are in a normal working state, the control module closes a hydraulic pipeline of the hydraulic module according to state information when the disc type electronic mechanical brake and the combined type electronic mechanical brake are in the normal working state, and simultaneously opens a brake oil can of the hydraulic module, so that the brake pedal module pushes brake fluid to flow into the brake oil can, and the vehicle is continuously braked through the disc type electronic mechanical brake and the combined type electronic mechanical brake; or when the disc type electronic mechanical brake and the combined type electronic mechanical brake of the brake execution module are in an abnormal working state, the control module starts a hydraulic pipeline of the hydraulic module according to the state information when the disc type electronic mechanical brake and the combined type electronic mechanical brake are in the abnormal working state, and simultaneously closes a brake oil can of the hydraulic module, so that the brake pedal module pushes brake fluid to flow into the hydraulic pipeline, and the vehicle is braked by the drum type hydraulic brake;
the hydraulic pipeline is used for conveying brake fluid for the drum type hydraulic brake.
By adopting the scheme, the driving wheel is braked by the disc type electronic mechanical brake, the driven wheel is braked by the combined type electronic mechanical brake, and the rear wheel is braked by the drum type hydraulic brake. When the electronic mechanical brake can work normally, the control module can continue to control the disc type electronic mechanical brake and the combined type electronic mechanical brake to brake the vehicle; when the electronic mechanical brake fails, the control module can control the drum type hydraulic brake to brake the vehicle. Thus, even if the electromechanical brake of the vehicle fails, the vehicle can be braked by the drum type hydraulic brake. The problem that the vehicle cannot be braked due to failure of an electronic mechanical brake of the vehicle is avoided, and the safety of the vehicle is improved.
According to another specific embodiment of the invention, the brake-by-wire brake system disclosed by the embodiment of the invention comprises a brake pedal and a power assisting device, wherein the brake pedal is connected with the power assisting device so as to transmit the pressure applied to the brake pedal to the power assisting device and generate mechanical energy, and the power assisting device is connected with the hydraulic module so as to transmit the mechanical energy to the hydraulic module.
By adopting the scheme, the force applied to the brake pedal is amplified by arranging the power assisting device, so that a driver can easily control the brake system of the vehicle.
According to another specific embodiment of the invention, the brake-by-wire system disclosed by the embodiment of the invention comprises a hydraulic module, a brake control module and a brake control module, wherein the hydraulic module comprises a first electromagnetic valve, a second electromagnetic valve, a hydraulic pipeline, a brake oil can and a brake master cylinder;
the first electromagnetic valve is respectively connected with the control module and the brake oil can so as to control the brake oil can to be opened or closed according to the state information received by the control module when the disc type electronic mechanical brake and the combined type electronic mechanical brake are in a normal working state or an abnormal working state;
the second electromagnetic valve is respectively connected with the control module and the hydraulic pipeline so as to control the closing or opening of the hydraulic pipeline according to the state information received by the control module when the disc type electronic mechanical brake and the combined type electronic mechanical brake are in a normal working state or an abnormal working state;
one side of the brake master cylinder is connected with the power assisting device so as to convert mechanical energy input by the brake pedal module into hydraulic energy; the other side of the master cylinder is connected with a hydraulic pipeline so as to push brake fluid to flow into the hydraulic pipeline by using hydraulic energy and brake the vehicle by a drum type hydraulic brake.
By adopting the scheme, the opening or closing of the brake oil can and the hydraulic pipeline is controlled by arranging the first electromagnetic valve and the second electromagnetic valve, and the vehicle can be effectively and quickly braked by the electronic mechanical brake or the drum type hydraulic brake.
According to another specific embodiment of the present invention, in the brake-by-wire system disclosed in the embodiment of the present invention, the first electromagnetic valve and the second electromagnetic valve are both normally closed electromagnetic valves.
According to another specific embodiment of the invention, the control module controls the disc type electronic mechanical brake and the combined type electronic mechanical brake to brake the vehicle according to the relation between the pedal stroke and the braking deceleration of the brake pedal.
By adopting the scheme, the disc type electronic mechanical brake and the combined type electronic mechanical brake are controlled according to the relation between the pedal stroke and the braking deceleration of the brake pedal to brake the vehicle, the clamping force applied to the wheels can be better controlled when the vehicle is braked, the pause and frustration caused by braking are reduced, and the use feeling is improved.
According to another specific embodiment of the invention, the brake-by-wire system disclosed by the embodiment of the invention, the control module comprises an electronic control unit and a vehicle body electronic stabilizing system, wherein the electronic control unit continuously controls the disc electronic mechanical brake and the combined electronic mechanical brake to brake the vehicle according to the state information when the disc electronic mechanical brake and the combined electronic mechanical brake are in the normal working state; and the electronic stability system of the vehicle body controls the drum type hydraulic brake to brake the vehicle according to the state information when the disc type electronic mechanical brake and the combined type electronic mechanical brake are in the abnormal working state.
By adopting the scheme, the electronic control unit and the automobile body electronic stabilizing system are arranged to respectively acquire the state information when the disc type electronic mechanical brake and the combined type electronic mechanical brake are in a normal working state and the state information when the disc type electronic mechanical brake and the combined type electronic mechanical brake are in an abnormal working state, so that the information acquisition efficiency is improved.
The embodiment of the invention also discloses a brake-by-wire control method, which utilizes the brake-by-wire system described in any embodiment above, and comprises the following steps:
judging whether the disc type electronic mechanical brake and the combined type electronic mechanical brake of the brake execution module brake normally;
if the braking state is normal, the vehicle is continuously braked by the disc type electronic mechanical brake and the combined type electronic mechanical brake;
and if the brake is abnormal, braking the vehicle by a drum type hydraulic brake of the brake execution module.
According to another specific embodiment of the present invention, the brake-by-wire method disclosed in the embodiment of the present invention, when the control module includes an electronic control unit and a body electronic stability system, continuing to brake the vehicle by the disk electromechanical brake and the combined electromechanical brake comprises:
the electronic control unit controls the second electromagnetic valve to close the hydraulic pipeline of the hydraulic module according to the state information when the disc type electronic mechanical brake and the combined type electronic mechanical brake are in the normal working state;
meanwhile, the electronic control unit controls the first electromagnetic valve to open a brake oil can of the hydraulic module according to the state information when the disc type electronic mechanical brake and the combined type electronic mechanical brake are in a normal working state;
the brake pedal module pushes the brake fluid of the hydraulic module to flow into the brake oil can;
calipers of the disc type electromechanical brake and the combined type electromechanical brake apply clamping force to vehicle tires according to control information of an electronic control unit to brake the vehicle.
According to another specific embodiment of the present invention, a brake-by-wire method is disclosed, in which a vehicle is braked by a drum brake of a brake execution module, comprising:
the electronic vehicle body stabilizing system controls the second electromagnetic valve to open a hydraulic pipeline of the hydraulic module according to state information when the disc type electronic mechanical brake and the combined type electronic mechanical brake are in an abnormal working state;
meanwhile, the electronic vehicle body stabilizing system controls the first electromagnetic valve to close a brake oil can of the hydraulic module according to state information when the disc type electronic mechanical brake and the combined type electronic mechanical brake are in an abnormal working state;
the brake pedal module pushes the brake fluid of the hydraulic module to flow into the hydraulic pipeline, so that the brake fluid pushes the drum type hydraulic brake to brake the vehicle.
The invention has the beneficial effects that:
the invention brakes the driving wheel through the disc type electronic mechanical brake, brakes the driven wheel through the combined type electronic mechanical brake, and brakes the rear wheel through the drum type hydraulic brake. When the electronic mechanical brake can work normally, the control module can control the opening of the first electromagnetic valve and the closing of the second electromagnetic valve, and then the brake oil can is opened while the hydraulic pipeline is closed. Therefore, the brake fluid directly flows into the brake oil can, and the disc type electronic mechanical brake and the combined type electronic mechanical brake can continuously brake the vehicle.
When the electronic mechanical brake fails, the control module can control the first electromagnetic valve to be closed and the second electromagnetic valve to be opened, and then the hydraulic pipeline is opened while the brake oil can is closed. Thus, the brake fluid essential oil hydraulic line pushes the drum type hydraulic brake, so that the drum type hydraulic brake brakes the vehicle. Therefore, even if the electromechanical brake of the vehicle fails, the vehicle can be braked by the drum type hydraulic brake. The problem that the vehicle cannot be braked due to failure of an electronic mechanical brake of the vehicle is avoided, and the safety of the vehicle is improved.
Drawings
FIG. 1 is a schematic structural diagram of a brake-by-wire system provided by an embodiment of the present invention;
fig. 2 is a schematic connection structure diagram of modules of a brake-by-wire system according to an embodiment of the present invention;
FIG. 3 is a flow chart of a brake-by-wire method according to an embodiment of the present invention;
fig. 4 is another schematic flow chart of the brake-by-wire method according to the embodiment of the present invention.
Description of reference numerals:
1. a brake pedal module; 11. a brake pedal; 12. a booster device; 2. a hydraulic module; 21. a first solenoid valve; 22. a second solenoid valve; 23. a hydraulic line; 24. a brake oil can; 25. a brake master cylinder; 3. a brake execution module; 31. a disk electromechanical brake; 32. a combined electromechanical brake; 33. a drum hydraulic brake; 4. a control module; 41. an electronic control unit; 42. a vehicle body electronic stabilization system.
Detailed Description
The following description of the embodiments of the present invention is provided for illustrative purposes, and other advantages and effects of the present invention will become apparent to those skilled in the art from the present disclosure. While the invention will be described in conjunction with the preferred embodiments, it is not intended that features of the invention be limited to these embodiments. On the contrary, the invention is described in connection with the embodiments for the purpose of covering alternatives or modifications that may be extended based on the claims of the present invention. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. The invention may be practiced without these particulars. Moreover, some of the specific details have been left out of the description in order to avoid obscuring or obscuring the focus of the present invention. It should be noted that the embodiments and features of the embodiments may be combined with each other without conflict.
It should be noted that in this specification, like reference numerals and letters refer to like items in the following drawings, and thus, once an item is defined in one drawing, it need not be further defined and explained in subsequent drawings.
In the description of the present embodiment, it should be noted that the terms "upper", "lower", "inner", "bottom", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings or orientations or positional relationships that are conventionally placed when the products of the present invention are used, and are only used for convenience in describing the present invention and simplifying the description, but do not indicate or imply that the devices or elements indicated must have specific orientations, be configured in specific orientations, and operate, and thus, should not be construed as limiting the present invention.
The terms "first," "second," and the like are used solely to distinguish one from another and are not to be construed as indicating or implying relative importance.
In the description of the present embodiment, it should be further noted that, unless explicitly stated or limited otherwise, the terms "disposed," "connected," and "connected" are to be interpreted broadly, e.g., as a fixed connection, a detachable connection, or an integral connection; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present embodiment can be understood in specific cases by those of ordinary skill in the art.
In order to make the objects, technical solutions and advantages of the present invention more apparent, embodiments of the present invention will be described in detail with reference to the accompanying drawings.
In order to solve the problem that a driver cannot operate a mechanical structure to enable a vehicle to generate deceleration when a mechanical brake-by-wire system in the prior art fails, so that the safety performance of the vehicle is affected, the embodiment of the invention provides a brake-by-wire control method. Referring to a schematic structural diagram of the brake-by-wire system provided by the embodiment of the present invention shown in fig. 1 and a schematic connection structural diagram of each module of the brake-by-wire system provided by the embodiment of the present invention shown in fig. 2, the brake-by-wire system provided by the embodiment of the present invention specifically includes: the brake system comprises a brake pedal module 1, a hydraulic module 2, a brake execution module 3 and a control module 4.
The brake pedal module 1 will first be explained with reference to fig. 1 and 2.
In this embodiment, the brake pedal module 1 is used to provide mechanical energy for a brake-by-wire system.
Further, the brake pedal module 1 includes a brake pedal 11 and a
Specifically, the brake pedal 1 is not substantially different from the brake pedal in the prior art, and the description of this embodiment is omitted. The boosting device 2 can amplify the force applied to the brake pedal 1 by the driver, and may be a vacuum booster, a hydraulic booster, a pneumatic booster, or the like, which is not limited in this embodiment.
Next, the hydraulic module 2 will be explained with reference to fig. 1 and 2.
In this embodiment, the hydraulic module 2 is connected to the brake pedal module 1 to convert mechanical energy input by the brake pedal module 1 into hydraulic energy.
Further, the hydraulic module 2 includes a first solenoid valve 21, a second solenoid valve 22, a
The first electromagnetic valve 21 is connected to the control module 4 and the brake oil can 24, respectively, so as to control the brake oil can 24 to be opened or closed according to the state information received by the control module 4 when the disc-type
The second electromagnetic valve 22 is respectively connected with the control module 4 and the
In the present embodiment, the
One side of the brake master cylinder 25 is connected with the
Preferably, in the present embodiment, the first electromagnetic valve 21 and the second electromagnetic valve 22 are both normally closed electromagnetic valves.
Next, the brake actuation module 3 will be explained with reference to fig. 1 and 2.
In this embodiment, the brake execution module 3 is connected to the hydraulic module 2, so that the brake fluid of the hydraulic module 2 pushes the brake execution module 3 to brake the vehicle.
In the present embodiment, the brake actuation module 3 includes a disc-type
It should be noted that the present embodiment is not particularly limited to the driving wheels and the driven wheels of the vehicle. When the vehicle is a four-wheel drive vehicle, the brake actuation module 3 includes only the disc-type
In the present embodiment, the disc
Next, the control module 4 will be explained with reference to fig. 1 and 2.
In this embodiment, the control module 4 is connected to the brake pedal module 11, the hydraulic module 2, and the brake execution module 3, respectively.
When the disc
When the disc electronic
In the present embodiment, the control module 4 controls the disc-type
Further, the control module 4 includes an electronic control unit 41 and a vehicle body electronic stabilization system 42, and the electronic control unit 41 continues to control the disc
The operation of the brake-by-wire system according to the embodiment of the present invention will be described in detail with reference to fig. 1 to 2.
When the vehicle can be normally braked, the disc type
When the disc type electronic
When the disc
By adopting the scheme, the driving wheel is braked by the disc type electronic mechanical brake, the driven wheel is braked by the combined type electronic mechanical brake, and the rear wheel is braked by the drum type hydraulic brake. When the electronic mechanical brake can work normally, the control module can control the opening of the first electromagnetic valve and the closing of the second electromagnetic valve, and then the brake oil can is opened while the hydraulic pipeline is closed. Therefore, the brake fluid directly flows into the brake oil can, and the disc type electronic mechanical brake and the combined type electronic mechanical brake can continuously brake the vehicle.
When the electronic mechanical brake fails, the control module can control the first electromagnetic valve to be closed and the second electromagnetic valve to be opened, and then the hydraulic pipeline is opened while the brake oil can is closed. Thus, the brake fluid essential oil hydraulic line pushes the drum type hydraulic brake, so that the drum type hydraulic brake brakes the vehicle. Therefore, even if the electromechanical brake of the vehicle fails, the vehicle can be braked by the drum type hydraulic brake. The problem that the vehicle cannot be braked due to failure of an electronic mechanical brake of the vehicle is avoided, and the safety of the vehicle is improved.
Based on the brake-by-wire system, the embodiment of the invention also discloses a brake-by-wire method. And the brake-by-wire method in the present embodiment utilizes the brake-by-wire system described in the above embodiment. The brake-by-wire method provided by the present embodiment is described below with reference to fig. 3 to 4.
Referring to fig. 3, a brake-by-wire method according to an embodiment of the present invention includes the following steps:
judging whether the disc type electronic mechanical brake and the combined type electronic mechanical brake of the brake execution module brake normally;
if the braking state is normal, the vehicle is continuously braked by the disc type electronic mechanical brake and the combined type electronic mechanical brake;
and if the brake is abnormal, braking the vehicle by a drum type hydraulic brake of the brake execution module.
In the present embodiment, the standard for the normal braking of the disc-type electromechanical brake and the combined-type electromechanical brake is that, after the brake pedal is depressed, the vehicle brakes according to the relationship between the preset pedal stroke and the braking deceleration and braking distance. Specifically, it can be understood that after the brake pedal is depressed for a certain distance, the braking deceleration is normally within a preset range, and the braking distance can be determined after the braking deceleration is constant. When the brake deceleration and the pedal travel are matched with the relation between the preset brake deceleration and the pedal travel, the disc type electronic mechanical brake and the combined type electronic mechanical brake are determined to be normal in braking.
And when the brake deceleration is not in a preset range after the brake pedal is stepped down for a certain stroke, the disc type electronic mechanical brake and the combined type electronic mechanical brake are judged to be abnormal in braking. In the actual driving process, when the vehicle shakes when the brake pedal is pressed, the steering wheel does not run in the original direction when the brake pedal is pressed, and the vehicle deflects to one side, the brake pedal does not return, the braking effect is not large, and the like, the disc type electronic mechanical brake and the combined type electronic mechanical brake are determined to be abnormal in braking.
Referring to fig. 4, in the present embodiment, when the control module includes the electronic control unit and the electronic body stabilization system, continuing to brake the vehicle by the disk-type electronic mechanical brake and the combined electronic mechanical brake includes:
the electronic control unit controls the second electromagnetic valve to close the hydraulic pipeline of the hydraulic module according to the state information when the disc type electronic mechanical brake and the combined type electronic mechanical brake are in the normal working state;
meanwhile, the electronic control unit controls the first electromagnetic valve to open a brake oil can of the hydraulic module according to the state information when the disc type electronic mechanical brake and the combined type electronic mechanical brake are in a normal working state;
the brake pedal module pushes the brake fluid of the hydraulic module to flow into the brake oil can;
calipers of the disc type electromechanical brake and the combined type electromechanical brake apply clamping force to vehicle tires according to control information of an electronic control unit to brake the vehicle.
It should be noted that, in the state information of the disk electromechanical brake and the combined electromechanical brake in the normal operating state, the state information in the normal operating state, that is, the information acquired by the electronic control unit when the disk electromechanical brake and the combined electromechanical brake are in the normal operating state.
With continued reference to fig. 4, in the present embodiment, a drum brake hydraulic vehicle that is braked by the brake actuation module includes:
the electronic vehicle body stabilizing system controls the second electromagnetic valve to open a hydraulic pipeline of the hydraulic module according to state information when the disc type electronic mechanical brake and the combined type electronic mechanical brake are in an abnormal working state;
meanwhile, the electronic vehicle body stabilizing system controls the first electromagnetic valve to close a brake oil can of the hydraulic module according to state information when the disc type electronic mechanical brake and the combined type electronic mechanical brake are in an abnormal working state;
the brake pedal module pushes the brake fluid of the hydraulic module to flow into the hydraulic pipeline, so that the brake fluid pushes the drum type hydraulic brake to brake the vehicle.
It should be noted that, in the state information of the disk electromechanical brake and the combined electromechanical brake in the abnormal operating state, the state information in the abnormal operating state, that is, the information acquired by the vehicle body electronic stability system when the disk electromechanical brake and the combined electromechanical brake fail, is included.
By adopting the scheme, the driving wheel is braked by the disc type electronic mechanical brake, the driven wheel is braked by the combined type electronic mechanical brake, and the rear wheel is braked by the drum type hydraulic brake. When the electronic mechanical brake can work normally, the control module can control the opening of the first electromagnetic valve and the closing of the second electromagnetic valve, and then the brake oil can is opened while the hydraulic pipeline is closed. Therefore, the brake fluid directly flows into the brake oil can, and the disc type electronic mechanical brake and the combined type electronic mechanical brake can continuously brake the vehicle.
When the electronic mechanical brake fails, the control module can control the first electromagnetic valve to be closed and the second electromagnetic valve to be opened, and then the hydraulic pipeline is opened while the brake oil can is closed. Thus, the brake fluid essential oil hydraulic line pushes the drum type hydraulic brake, so that the drum type hydraulic brake brakes the vehicle. Therefore, even if the electromechanical brake of the vehicle fails, the vehicle can be braked by the drum type hydraulic brake. The problem that the vehicle cannot be braked due to failure of an electronic mechanical brake of the vehicle is avoided, and the safety of the vehicle is improved.
While the invention has been shown and described with reference to certain preferred embodiments thereof, it will be understood by those skilled in the art that the foregoing is a more detailed description of the invention, taken in conjunction with the specific embodiments thereof, and that no limitation of the invention is intended thereby. Various changes in form and detail, including simple deductions or substitutions, may be made by those skilled in the art without departing from the spirit and scope of the invention.