An anti-lock braking system

Abstract

The embodiment of the application provides an anti-lock braking system, which can not change the structure of a traditional anti-lock braking system, only add an electromagnetic valve, multiple sets of check valves and supporting control logic, so that the anti-lock braking system has the functions of auxiliary parking and the like, thereby maintaining a low cost and meeting more needs of users. The anti-lock braking system comprises an anti-lock braking control module, a brake master cylinder, an electromagnetic valve, a front wheel braking module, a rear wheel braking module and a check valve group. The anti-lock braking control module is used for sending an auxiliary parking signal to the electromagnetic valve, the front wheel braking module and the rear wheel braking module. The brake master cylinder is used for outputting a first set amount of brake fluid according to a brake pedal stroke. The electromagnetic valve is used for closing a first liquid outlet and a second liquid outlet and connecting a third liquid outlet in response to the auxiliary parking signal. The front wheel braking module and the rear wheel braking module are used for keeping the brake pressure of the front wheel and the rear wheel at a first set pressure value in response to the auxiliary parking signal.

Description

[Technical Field]

[0001] This application relates to the field of vehicle braking system technology, and more particularly to an anti-lock braking system. [Background Technology]

[0002] Currently, the braking control system used in vehicles is mainly the Anti-lock Braking System (ABS). However, because the ABS system installed in vehicles only has the function of intermittent braking to prevent wheel lock-up, its functionality is limited and cannot meet the diverse functional needs of users. [Summary of the Invention]

[0003] This application provides an anti-lock braking system that, without altering the structure of a traditional anti-lock braking system, adds solenoid valves, multiple sets of one-way valves, and matching control logic to enable the anti-lock braking system to have additional functions such as auxiliary parking. This improves upon the single functionality of traditional anti-lock braking systems while maintaining a low cost, and adapts to a wider range of user needs.

[0004] This application provides an anti-lock braking system, which includes: an anti-lock braking control module, a master cylinder, a solenoid valve, a front wheel braking module, a rear wheel braking module, and a one-way valve assembly. The anti-lock braking control module is electrically connected to the master cylinder, the solenoid valve, the front wheel braking module, and the rear wheel braking module. The outlet of the master cylinder is connected to the inlet of the solenoid valve. The first outlet of the solenoid valve is connected to the first inlet of the front wheel braking module, the second outlet of the solenoid valve is connected to the first inlet of the rear wheel braking module, and the third outlet of the solenoid valve is connected to the inlet of the one-way valve assembly. The front wheel outlet of the one-way valve assembly is connected to the second inlet of the front wheel braking module, and the rear wheel outlet of the one-way valve assembly is connected to the second inlet of the rear wheel braking module. The first and second outlets of the solenoid valve are normally open, and the third outlet is normally closed.

[0005] The anti-lock braking control module is configured to, in response to a vehicle speed greater than a speed threshold and an actual brake pedal travel greater than or equal to a first preset travel, send a first working signal to the master cylinder and a braking signal to the front wheel braking module and the rear wheel braking module; or, in response to a vehicle speed of zero and an actual brake pedal travel greater than or equal to the first preset travel, send a second working signal to the master cylinder and an auxiliary parking signal to the solenoid valve, the front wheel braking module, and the rear wheel braking module, wherein the first working signal and the second working signal include the actual brake pedal travel;

[0006] The master cylinder is used to respond to the first working signal or the second working signal, and output a set output amount of brake fluid corresponding to the actual travel of the brake pedal, based on the mapping relationship between the brake pedal travel and the brake fluid output amount.

[0007] The solenoid valve is used to close the first liquid outlet and the second liquid outlet in response to the auxiliary parking signal, and connect the third liquid outlet.

[0008] The front wheel braking module is used to receive the brake fluid in response to the braking signal to perform a preset anti-lock braking function on the front wheels of the vehicle; or, in response to the auxiliary parking signal, to maintain the braking pressure of the front wheels of the vehicle at a first preset pressure value through the brake fluid of the set output amount.

[0009] The rear wheel braking module is used to respond to the braking signal, receive the brake fluid to perform the preset anti-lock braking function on the rear wheels of the vehicle; or, in response to the auxiliary parking signal, maintain the braking pressure of the rear wheels of the vehicle at the first preset pressure value through the brake fluid of the set output amount.

[0010] In this embodiment, by adding a solenoid valve, a one-way valve assembly, and matching control logic to the components of a traditional anti-lock braking system, a signal is sent when the vehicle brake pedal is depressed to a first set travel and the vehicle speed is zero. This signals the master cylinder to output a set amount of brake fluid to help the user stabilize the vehicle in a braking state by pressing the brake pedal without engaging the handbrake, thus preventing the vehicle from rolling. In this way, the original anti-lock braking function is enhanced by using low-cost solenoid valves and one-way valve assemblies to add a function that assists the user in temporarily parking the vehicle, meeting the user's diverse functional needs.

[0011] Optionally, the anti-lock braking control module is also used to, after sending the auxiliary parking signal, respond to the driver's seat belt not being locked or the driver's side door being opened and the handbrake not being released, to obtain the vehicle's real-time slope and real-time load.

[0012] The anti-lock braking control module is also used to send a third working signal to the master cylinder and a handbrake alarm signal to the front wheel brake module and the rear wheel brake module. The third working signal includes the real-time slope and the real-time load.

[0013] The master cylinder is also used to respond to the third working signal and, based on the mapping relationship between slope, load and brake fluid increment, output the brake fluid of the set increment corresponding to the real-time slope and real-time load.

[0014] The front wheel braking module is also used to respond to the handbrake alarm signal by maintaining the braking pressure of the front wheels of the vehicle at a second set pressure value through the brake fluid of the set output amount and the set increment.

[0015] The rear wheel braking module is also used to respond to the handbrake alarm signal by maintaining the braking pressure of the vehicle's rear wheels at the second set pressure value through the brake fluid of the set output amount and the set increment.

[0016] In this embodiment, when the vehicle's handbrake is not engaged and the driver's seatbelt is not locked or the driver's side door is open, it is determined that the user may have failed to engage the handbrake before leaving the vehicle. Based on real-time slope, real-time load, and other vehicle data, a signal carrying preset incremental data is sent to control the master cylinder to increase the output of brake fluid and increase the braking pressure of the front and rear wheels. This reduces the risk of the vehicle rolling away due to the user leaving the vehicle without engaging the handbrake and improves the safety of the vehicle when parked.

[0017] Optionally, the anti-lock braking control module is further configured to, after sending the handbrake alarm signal, in response to the handbrake being released, send a fourth working signal to the master cylinder and send a handbrake release signal to the solenoid valve, the front wheel brake module and the rear wheel brake module;

[0018] The master cylinder is also used to draw brake fluid through the outlet of the master cylinder in response to the fourth working signal.

[0019] The solenoid valve is also used to connect the first liquid outlet and the second liquid outlet in response to the handbrake opening signal, and to close the third liquid outlet.

[0020] The front wheel braking module is also used to respond to the handbrake release signal by causing the brake fluid to flow back along the first inlet of the front wheel braking module until the braking pressure of the front wheels of the vehicle returns to zero.

[0021] The rear wheel braking module is also configured to respond to the handbrake release signal by causing the brake fluid to flow back along the first inlet of the rear wheel braking module until the braking pressure of the vehicle's rear wheels returns to zero.

[0022] In this embodiment, after sending a handbrake alarm signal, when the anti-lock braking control module detects that the handbrake has been reopened, it determines that the vehicle has avoided the risk of rolling away by opening the handbrake. It then controls the brake fluid return to reduce the braking pressure output by the anti-lock braking system, thereby enabling the vehicle's anti-lock braking system to automatically reduce the braking pressure to zero when braking is not necessary, protecting vulnerable components such as valves from deformation and damage due to prolonged high braking pressure.

[0023] Optionally, the anti-lock braking control module is further configured to, after sending the auxiliary parking signal or the handbrake alarm signal, respond to the actual travel of the accelerator pedal being greater than the second set travel and the engine output torque being greater than the set starting torque, and without having sent the handbrake release signal after the handbrake alarm signal, send a fifth working signal to the brake master cylinder, and send a steep slope start signal to the solenoid valve, the front wheel brake module and the rear wheel brake module;

[0024] The master cylinder is also used to draw brake fluid through the inlet of the master cylinder in response to the fifth working signal;

[0025] The solenoid valve is also used to respond to the steep slope start signal, connect the first liquid outlet and the second liquid outlet, and close the third liquid outlet;

[0026] The front wheel braking module is also used to respond to the steep slope start signal by causing the brake fluid to flow back along the first inlet of the front wheel braking module until the braking pressure of the front wheels of the vehicle returns to zero.

[0027] The rear wheel braking module is also configured to respond to the steep slope start signal by causing the brake fluid to flow back along the first inlet of the rear wheel braking module until the braking pressure of the vehicle's rear wheels returns to zero.

[0028] In this embodiment, after the user completes parking with the assistance of the anti-lock braking system, the engine output torque is obtained to determine whether the vehicle is about to start driving and whether the output torque is sufficient for normal vehicle driving. If the output torque meets the conditions, the braking pressure is automatically reduced to zero, so that the vehicle can start driving normally.

[0029] Optionally, the front wheel braking module includes: a first inlet valve, a second inlet valve, a front wheel return pump, a front left wheel cylinder, and a front right wheel cylinder; wherein, the first outlet of the solenoid valve is connected to the inlet of the first inlet valve and the inlet of the second inlet valve, the front wheel outlet of the one-way valve assembly is connected to the inlet of the front wheel return pump, the outlet of the front wheel return pump is connected to the inlet of the first inlet valve and the inlet of the second inlet valve, the outlet of the first inlet valve is connected to the inlet of the front left wheel cylinder, and the outlet of the second inlet valve is connected to the inlet of the front right wheel cylinder;

[0030] The front wheel return pump is used to respond to the auxiliary parking signal by drawing the brake fluid of the set output amount from the master cylinder to the inlet of the first inlet valve and the inlet of the second inlet valve.

[0031] The first inlet valve is used to open the valve in response to the auxiliary parking signal, so that the set output amount of brake fluid flows into the front left wheel cylinder;

[0032] The second inlet valve is used to open the valve in response to the auxiliary parking signal, so that the set output amount of brake fluid flows into the front right wheel cylinder;

[0033] The front left wheel cylinder is used to receive the brake fluid inflow of the set output amount and maintain the braking pressure of the vehicle's left front wheel at the first set pressure value;

[0034] The front right wheel cylinder is used to receive the brake fluid inflow of the set output amount and maintain the braking pressure of the right front wheel of the vehicle at the first set pressure value.

[0035] In this embodiment, by adding supporting control logic for the front wheel braking module to the anti-lock braking control module based on the existing system, and changing the flow direction of brake fluid in the front wheel return pump section to deliver brake fluid to the first and second inlet valves, the anti-lock braking control module can control the wheel cylinders and inlet valves in the front wheel braking module to complete the corresponding braking action when the user triggers the auxiliary parking signal of the anti-lock braking system by pressing the brake pedal. This keeps the braking pressure of the front wheels unchanged at the first set pressure value, thus realizing the auxiliary parking function that the original anti-lock braking system does not have.

[0036] Optionally, the rear wheel braking module includes: a third inlet valve, a fourth inlet valve, a rear wheel return pump, a rear left wheel cylinder, and a rear right wheel cylinder; wherein, the second outlet of the solenoid valve is connected to the inlet of the third inlet valve and the inlet of the fourth inlet valve respectively; the rear wheel outlet of the one-way valve assembly is connected to the inlet of the rear wheel return pump; the outlet of the rear wheel return pump is connected to the inlet of the third inlet valve and the inlet of the fourth inlet valve respectively; the outlet of the third inlet valve is connected to the inlet of the rear left wheel cylinder; the outlet of the fourth inlet valve is connected to the inlet of the rear right wheel cylinder; and the rear wheel return pump is mechanically connected to the front wheel return pump via a drive shaft.

[0037] The rear wheel return oil pump is used to respond to the auxiliary parking signal to draw the brake fluid of the set output amount from the master cylinder to the inlet of the third inlet valve and the inlet of the fourth inlet valve.

[0038] The third inlet valve is used to open the valve in response to the auxiliary parking signal, so that the set output amount of brake fluid flows into the rear left wheel cylinder;

[0039] The fourth inlet valve is used to open the valve in response to the auxiliary parking signal, so that the set output amount of brake fluid flows into the rear right wheel cylinder;

[0040] The rear left wheel cylinder is used to receive the brake fluid inflow of the set output amount and maintain the braking pressure of the vehicle's left rear wheel at the first set pressure value.

[0041] The rear right wheel cylinder is used to receive the brake fluid inflow of the set output amount and maintain the braking pressure of the right rear wheel of the vehicle at the first set pressure value.

[0042] In this embodiment, by adding supporting control logic for the rear wheel braking module to the anti-lock braking control module based on the existing system, and changing the flow direction of brake fluid in the rear wheel return pump pipeline to deliver brake fluid to the third and fourth inlet valves, the anti-lock braking control module can control the wheel cylinders and inlet valves in the rear wheel braking module to complete the corresponding braking action when the user triggers the auxiliary parking signal of the anti-lock braking system by pressing the brake pedal. This ensures that the braking pressure of the rear wheels remains unchanged at the first set pressure value, thus realizing the auxiliary parking function that the original anti-lock braking system does not have.

[0043] Optionally, the system further includes: a first check valve, a second check valve, a third check valve, a fourth check valve, a fifth check valve, and a sixth check valve, wherein the inlet of the first check valve is connected to the outlet of the first inlet valve, and the outlet of the first check valve is connected to the inlet of the first inlet valve; the inlet of the second check valve is connected to the outlet of the second inlet valve, and the outlet of the second check valve is connected to the inlet of the second inlet valve; the inlet of the third check valve is connected to the outlet of the third inlet valve. The outlet of the third check valve is connected to the inlet of the third inlet valve; the inlet of the fourth check valve is connected to the outlet of the fourth inlet valve, and the outlet of the fourth check valve is connected to the inlet of the fourth inlet valve; the inlet of the fifth check valve is connected to the inlet of the front return oil pump, and the outlet of the fifth check valve is connected to the outlet of the front return oil pump; the inlet of the sixth check valve is connected to the inlet of the rear return oil pump, and the outlet of the sixth check valve is connected to the outlet of the rear return oil pump.

[0044] The first check valve, the second check valve, the third check valve, and the fourth check valve are all used to ensure that the first and second outlets of the solenoid valve are normally open, the third outlet is normally closed, and the brake fluid flows back to the master cylinder along the first, second, third, and fourth inlet valves, so that the brake fluid flows back along the branch where the first check valve, the second check valve, the third check valve, and the fourth check valve are located; or, when the first and second outlets of the solenoid valve are normally open and the third outlet is normally closed, the brake fluid is prevented from flowing back along a path opposite to the preset flow direction.

[0045] The fifth check valve and the sixth check valve are both used to prevent the brake fluid from flowing back along the path opposite to the preset flow direction when the first outlet and the second outlet of the solenoid valve are kept open and the third outlet is kept closed.

[0046] The one-way valve assembly includes a seventh one-way valve and an eighth one-way valve, wherein the third outlet of the solenoid valve is connected to the inlet of the seventh one-way valve and the inlet of the eighth one-way valve, respectively; the outlet of the seventh one-way valve is connected to the inlet of the front circulation oil pump; and the outlet of the eighth one-way valve is connected to the inlet of the rear circulation oil pump.

[0047] The seventh one-way valve is used to prevent brake fluid flowing to the front left wheel cylinder and the front right wheel cylinder from flowing into the rear left wheel cylinder and the rear right wheel cylinder when the first outlet and the second outlet of the solenoid valve are normally open and the third outlet is normally closed.

[0048] The eighth one-way valve is used to prevent brake fluid flowing to the rear left wheel cylinder and the rear right wheel cylinder from flowing into the front left wheel cylinder and the front right wheel cylinder when the first outlet and the second outlet of the solenoid valve are kept open and the third outlet is kept closed.

[0049] In this embodiment, by adding first to fourth check valves in parallel to each inlet valve of the anti-lock braking system, the brake fluid can simultaneously pass through the branches where the first to fourth check valves are located when it flows back to the master cylinder along the pipeline, increasing the return flow rate. At the same time, fifth to sixth check valves are added in parallel to each of the two return pumps, and seventh to eighth check valves are added at the locations where the solenoid valve leads to the two return pumps, preventing the brake fluid from flowing along the opposite path of the preset flow direction. Thus, the first to eighth check valves are used to restrict the reverse flow of brake fluid into pipelines unrelated to the current function, control the turbulent flow of brake fluid, and ensure that the anti-lock braking system can perform its relevant functions normally.

[0050] Optionally, the front wheel return pump is further configured to, in response to the handbrake alarm signal, draw the brake fluid of the set increment to the inlet of the first inlet valve and the inlet of the second inlet valve;

[0051] The first inlet valve is also used to open the valve in response to the handbrake alarm signal, so that the brake fluid of the set increment flows into the front left wheel cylinder;

[0052] The second inlet valve is used to open the valve in response to the handbrake alarm signal, allowing the brake fluid of the set increment to flow into the front right wheel cylinder;

[0053] The front left wheel cylinder is used to receive the brake fluid inflow of the set increment, and to maintain the braking pressure of the vehicle's left front wheel at the second set pressure value through the brake fluid of the set increment and the set output amount.

[0054] The front right wheel cylinder is used to receive the brake fluid inflow of the set output amount and the set increment, and to maintain the braking pressure of the right front wheel of the vehicle at the second set pressure value through the brake fluid of the set increment and the set output amount.

[0055] In this embodiment, by configuring handbrake alarm-related control logic for the front wheel brake module in the anti-lock braking control module, when it is determined that the user has exited the vehicle without engaging the handbrake and there is a risk of the vehicle rolling away, the third and fourth inlet valves of the front wheel brake module are automatically opened, and additional brake fluid is injected into the wheel cylinders to increase the braking pressure of the front wheels to a second set pressure value. This ensures that the vehicle will not roll away due to user negligence, thereby improving the safety of the vehicle when parked.

[0056] Optionally, the first inlet valve is further configured to open the valve in response to the handbrake release signal, allowing the brake fluid of the set output amount and the set increment to flow back from the front left wheel cylinder to the master cylinder;

[0057] The second inlet valve is used to open the valve in response to the handbrake release signal, so that the brake fluid of the set output amount and the set increment flows back from the front right wheel cylinder to the master cylinder;

[0058] The front left wheel cylinder is used to reduce the braking pressure of the vehicle's left front wheel to zero after the brake fluid has completely returned.

[0059] The front right wheel cylinder is used to reduce the braking pressure of the right front wheel of the vehicle to zero after the brake fluid has completely returned.

[0060] In this embodiment, after the user engages the handbrake, the first and second inlet valves are opened, allowing the brake fluid in the wheel cylinders to flow back to the master cylinder to reduce the braking pressure of the front wheels to zero. This achieves a switch from braking by the anti-lock braking module to braking by the handbrake, protecting the weak components in the front wheel braking module from deformation due to prolonged high braking pressure.

[0061] Optionally, the first inlet valve is further configured to open the valve in response to the steep slope start signal, allowing the brake fluid of the set output amount and the set increment to flow back from the front left wheel cylinder to the master cylinder;

[0062] The second inlet valve is used to open the valve in response to the steep slope start signal, so that the brake fluid of the set output amount and the set increment flows back from the front right wheel cylinder to the master cylinder;

[0063] The front left wheel cylinder is used to reduce the braking pressure of the vehicle's left front wheel to zero after the brake fluid has completely returned.

[0064] The front right wheel cylinder is used to reduce the braking pressure of the right front wheel of the vehicle to zero after the brake fluid has completely returned.

[0065] In this embodiment, by adding control logic related to hill start to the anti-lock braking module, when the vehicle is about to enter normal driving and does not need to continue braking through the anti-lock braking system, the first inlet valve, the second inlet valve and the wheel cylinder are controlled in time to perform actions, opening the return path of the brake fluid and reducing the braking pressure to zero, thereby avoiding damage to weak components such as valves due to prolonged pressurization, thus ensuring that the vehicle can release the brake in time and start normally. [Attached Image Description]

[0066] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this specification. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0067] Figure 1 This application provides a schematic diagram of the module connection relationship of an anti-lock braking system.

[0068] Figure 2 This is a schematic diagram of the structure of a front wheel braking module provided in an embodiment of this application;

[0069] Figure 3 This is a schematic diagram of the structure of a rear wheel braking module provided in an embodiment of this application;

[0070] Figure 4 A schematic diagram of the brake fluid flow direction for an anti-lock braking system performing a handbrake alarm function, provided in an embodiment of this application;

[0071] Figure 5 This application provides a schematic diagram of the structure of a front wheel braking module when performing the handbrake alarm function.

[0072] Figure 6 This application provides a schematic diagram of the structure of an anti-lock braking system that detects the handbrake being engaged, as shown in the embodiments of the present application.

[0073] Figure 7 This application provides a schematic diagram of the structure of a front wheel braking module when it receives a handbrake activation signal.

[0074] Figure 8 A schematic diagram of the structure of an anti-lock braking system that detects vehicle startup is provided in an embodiment of this application;

[0075] Figure 9 A schematic diagram of the structure of a front wheel braking module when receiving a steep slope start signal, provided in an embodiment of this application;

[0076] Figure 10 This is a schematic diagram of the structure of an anti-lock braking system after adding multiple sets of one-way valves according to an embodiment of this application.

Detailed Implementation Methods

[0077] To better understand the technical solutions in this specification, the embodiments of this application will be described in detail below with reference to the accompanying drawings.

[0078] It should be understood that the described embodiments are merely some, not all, of the embodiments in this specification. All other embodiments obtained by those skilled in the art based on the embodiments in this specification without inventive effort are within the scope of protection of this specification.

[0079] The terminology used in the embodiments of this application is for the purpose of describing particular embodiments only and is not intended to be limiting of this specification. The singular forms “a,” “the,” and “the” used in the embodiments of this application and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise.

[0080] Currently, the most widely used braking control system in vehicles is the Anti-lock Braking System (ABS). However, because the ABS system only has the function of intermittent braking to prevent wheel lock-up, its functionality is relatively simple and cannot meet the diverse needs of users for vehicle braking functions.

[0081] In view of this, the present application provides an anti-lock braking system that, without changing the structure of a traditional anti-lock braking system, enables the anti-lock braking system to have additional functions such as auxiliary parking and handbrake alarm by installing solenoid valves and multiple sets of one-way valves in the pipeline and adding matching control logic to the anti-lock braking system. This improves the shortcomings of the traditional anti-lock braking system in terms of its single function while maintaining a low cost, and meets the richer usage needs of users.

[0082] It should be understood that the module connection structure of the ABS system given in the embodiments of this application is only one possible and relatively simplified implementation method, and not the only implementation method of the anti-lock braking system in the embodiments of this application. For example, in terms of the connection relationship of the brake wheel cylinders, commercial vehicles, due to higher requirements for the control precision of braking pressure, usually use a method where the front wheel brake wheel cylinders and the rear wheel brake wheel cylinders are braked separately. Therefore, it can be adapted to the connection relationship description of "front wheel brake module" and "rear wheel brake module" in the embodiments of this application. However, in order to ensure the uniform distribution of braking pressure, passenger vehicles usually use a method where the left front wheel and right rear wheel, and the left rear wheel and right front wheel are connected to the brake master cylinder in a cross pair. Although this control structure that connects the front and rear wheels of the vehicle with "X"-shaped pipelines cannot be simply divided into front wheel brake module and rear wheel brake module, since it only changes the connection relationship between the four front and rear brake wheel cylinders from parallel connection to cross connection, and does not change much in the overall control concept of the anti-lock braking system, the technical solution provided in the embodiments of this application can still be adapted to the ABS system structure of passenger vehicles after fine-tuning the structure and control logic.

[0083] Meanwhile, since traditional ABS systems employ both hydraulic and pneumatic braking methods, the difference lies only in that hydraulic braking systems transmit braking pressure via liquid, while pneumatic braking systems transmit braking pressure via compressed gas. There is no fundamental difference in the piping connections or braking principles. Therefore, this application uses the more commonly used hydraulic braking system in existing vehicle models as an example for illustration, merely to facilitate the explanation of the technical principles of this application's embodiments. It does not imply that the technical solutions provided in this application's embodiments become unapplicable after changing the pressure transmission medium in the ABS system.

[0084] The technical solutions provided in the embodiments of this application will now be described in conjunction with the accompanying drawings.

[0085] Please see Figure 1 This is a schematic diagram of the module connection relationship of an anti-lock braking system provided in an embodiment of this application. The system includes:

[0086] The system includes an anti-lock braking system (ABS) control module 101, a master cylinder 102, a solenoid valve 103, a front wheel brake module 104, a rear wheel brake module 105, and a one-way valve assembly 106. The ABS control module 101 is electrically connected to the master cylinder 102, solenoid valve 103, front wheel brake module 104, and rear wheel brake module 105. The outlet of the master cylinder 102 is connected to the inlet of the solenoid valve 103, and the first outlet of the solenoid valve 103 is connected to the first outlet of the front wheel brake module 104. The inlet ports are connected as follows: the second outlet port of the solenoid valve 103 is connected to the first inlet port of the rear wheel brake module 105; the third outlet port of the solenoid valve 103 is connected to the inlet port of the one-way valve assembly 106; the front wheel outlet port of the one-way valve assembly 106 is connected to the second inlet port of the front wheel brake module 104; and the rear wheel outlet port of the one-way valve assembly 106 is connected to the second inlet port of the rear wheel brake module 105. The first and second outlet ports of the solenoid valve 103 are normally open, and the third outlet port is normally closed.

[0087] The anti-lock braking control module 101 is used to send a first working signal to the master cylinder 102 and a braking signal to the front wheel braking module 104 and the rear wheel braking module 105 in response to a vehicle speed greater than a speed threshold and an actual brake pedal travel greater than or equal to a first set travel; or, in response to a vehicle speed of zero and an actual brake pedal travel greater than or equal to the first set travel, send a second working signal to the master cylinder 102 and an auxiliary parking signal to the solenoid valve 103, the front wheel braking module 104 and the rear wheel braking module 105. The first working signal and the second working signal include the actual brake pedal travel.

[0088] The master cylinder 102 is used to respond to a first working signal or a second working signal and output a set output amount of brake fluid corresponding to the actual travel of the brake pedal, based on the mapping relationship between the brake pedal travel and the brake fluid output amount.

[0089] Solenoid valve 103 is used to close the first liquid outlet and the second liquid outlet in response to the auxiliary parking signal, and connect the third liquid outlet.

[0090] The front wheel braking module 104 is used to receive brake fluid in response to a braking signal to perform a preset anti-lock braking function on the front wheels of the vehicle; or, in response to an auxiliary parking signal, to maintain the braking pressure of the front wheels of the vehicle at a first preset pressure value by using a set output amount of brake fluid.

[0091] The rear wheel braking module 105 is used to respond to a braking signal, receive brake fluid to perform a preset anti-lock braking function on the rear wheels of the vehicle; or, in response to an auxiliary parking signal, maintain the braking pressure of the rear wheels of the vehicle at a first preset pressure value by using a set output of brake fluid.

[0092] In this embodiment, the anti-lock braking control module 101 in the ABS system plays the core role of automatic calculation and control in the system, while the master cylinder 102, solenoid valve 103, front wheel brake module 104, rear wheel brake module 105 and one-way valve group 106 are all actuators in the ABS system, responsible for performing corresponding actions according to the signals issued by the anti-lock braking control module 101.

[0093] It should be understood that since the ABS system in this application embodiment is a modification of the existing vehicle ABS system, it still possesses basic anti-lock braking functionality when additional functions are added. That is, when the brake pedal travel is large and the vehicle speed is too high, the ABS system provided in this application embodiment can also achieve the effect of keeping the wheels in an alternating state of rolling and locking to maintain the maximum adhesion between the wheels and the ground.

[0094] Beyond anti-lock braking (ABS), when a user needs to temporarily stop a vehicle while driving, vehicles equipped with traditional ABS systems can only lock the wheels by having the user keep the brake pedal firmly pressed or by engaging the handbrake (or parking brake). However, keeping the brake pedal firmly pressed is obviously very inconvenient for the user. Handbrakes, being mostly spring-operated, provide less stable and harder-to-control braking force, and frequent use can put additional pressure and wear on tires, brake discs, and other components. Furthermore, users may cause mechanical damage by forgetting to disengage the handbrake and forcibly starting the vehicle. In summary, both keeping the brake pedal firmly pressed and engaging the handbrake for parking when temporarily stopping a vehicle have certain drawbacks.

[0095] Therefore, the ABS system provided in this application embodiment, in addition to its anti-lock braking function, also utilizes the brake pedal to assist the user in temporarily parking the vehicle. Furthermore, the user only needs to press the pedal once, and the vehicle can maintain a high braking pressure according to the user's pedal travel to prevent rolling backwards, without needing to continuously press the brake pedal to lock the wheels, thus improving reliability and convenience.

[0096] Specifically, when a user presses the brake pedal to temporarily park the vehicle, the anti-lock braking system (ABS) control module 101 first checks if the vehicle speed is zero. If it is zero, it calculates the corresponding brake fluid output based on the actual travel of the brake pedal. After calculation, the ABS control module 101 sends a first operating signal carrying the set output value to the master cylinder 102, and sends an auxiliary parking signal to the solenoid valve 103, the front wheel brake module 104, and the rear wheel brake module 105 to instruct these components to increase the braking pressure accordingly. The methods for sending these two signals include, but are not limited to, sending a message carrying an identification code to the corresponding component via a Controller Area Network (CAN) bus or a Local Interconnect Network (LIN) line. The message contains the specific actions that the component needs to perform.

[0097] First, upon receiving the first operating signal, the master cylinder 102 draws brake fluid from its connected reservoir based on the set output amount data carried in the first operating signal, and outputs it into the pipeline through the inlet of the master cylinder 102 connected to the solenoid valve 103. Simultaneously, upon receiving the auxiliary parking signal, the solenoid valve 103 manipulates its valve core to change position, causing the first and second outlets of the solenoid valve 103 to close from a normally open state, and the third outlet to open from a normally closed state. Through this action, the operating mode of the ABS system switches from conventional anti-lock braking to auxiliary parking; the brake fluid in the pipeline also changes from the conventional flow direction of flowing through the solenoid valve 103 into the front wheel brake module 104 and rear wheel brake module 105 respectively, to a flow direction that requires passing through the solenoid valve 103 and the one-way valve assembly 106 to flow into the front wheel brake module 104 and rear wheel brake module 105. The one-way valve assembly 106 itself has the function of restricting the direction of brake fluid flow, which temporarily blocks the brake fluid return path of the ABS system in the assisted parking state, and does not release the braking pressure of the wheels when the user releases the brake pedal.

[0098] Subsequently, upon receiving the auxiliary parking signal, the front wheel braking module 104 and the rear wheel braking module 105 apply brake fluid of a set output quantity delivered from the master cylinder 102 to the front and rear wheels of the vehicle. Since the brake fluid return path has been cut off at this time, the front wheel braking module 104 and the rear wheel braking module 105 can maintain the braking pressure on the wheels at the first set pressure value, ensuring that the vehicle remains parked as required by the user without rolling backwards.

[0099] It should be noted that the anti-lock braking control module 101 in the embodiments of this application can be any microcontroller (such as an electronic control unit) or general-purpose computing device with control functions, and the components of these microcontrollers or general-purpose computing devices may include, but are not limited to: one or more processors or processing units, system memory, buses connecting different system components (including system memory and processing units), etc.

[0100] Meanwhile, the components in the ABS system actuator are not limited to the component models described in the embodiments of this application, but can be replaced with any other element or device with the same function. For example, for a conventional brake master cylinder 102 with two lines (line ① and line ②), the matching solenoid valve 103 can be a two-position five-way solenoid valve, or a valve group consisting of a common two-way solenoid valve connected to line ① and a two-position two-way solenoid valve connected to line ②, or any other solenoid valve combination that is equivalent to the above combination. When the brake master cylinder 102 has only one line, or has two or more lines for outputting brake fluid, the matching solenoid valve 103 can still include a two-position six-way solenoid valve and other implementations with similar effects. Similarly, the solenoid valve 103 can also be equivalently replaced with a purely mechanical valve with a reversing function; when receiving the relevant signal sent by the anti-lock braking control module 101, the vehicle can manually, mechanically (such as by linkage), hydraulically, or electro-hydraulically drive the valve core to reposition, so as to achieve the same reversing effect as the solenoid valve 103 described above.

[0101] When the vehicle responds to the user pressing the brake pedal and activates the assisted parking function, the front wheel braking module 104 and the rear wheel braking module 105 need to brake the front and rear wheels of the vehicle respectively to prevent the vehicle from rolling. The specific braking process of the front wheel braking module 104 and the rear wheel braking module 105 respectively after receiving the assisted parking signal is described below:

[0102] Figure 2 This is a schematic diagram of the structure of a front wheel braking module 104 provided in an embodiment of this application. As one possible implementation, the front wheel braking module 104 includes: a first inlet valve 201, a second inlet valve 202, a front wheel return pump 203, a front left wheel cylinder 204, and a front right wheel cylinder 205; wherein, the first outlet of the solenoid valve 103 is connected to the inlet of the first inlet valve 201 and the inlet of the second inlet valve 202, the front wheel outlet of the one-way valve assembly 106 is connected to the inlet of the front wheel return pump 203, the outlet of the front wheel return pump 203 is connected to the inlet of the first inlet valve 201 and the inlet of the second inlet valve 202, the outlet of the first inlet valve 201 is connected to the inlet of the front left wheel cylinder 204, and the outlet of the second inlet valve 202 is connected to the inlet of the front right wheel cylinder 205;

[0103] The front wheel return pump 203 is used to draw a set output amount of brake fluid from the master cylinder 102 to the inlet of the first inlet valve 201 and the inlet of the second inlet valve 202 in response to the auxiliary parking signal.

[0104] The first inlet valve 201 is used to open the valve in response to the auxiliary parking signal so that the set output amount of brake fluid flows into the front left wheel cylinder 204;

[0105] The second inlet valve 202 is used to open the valve in response to the auxiliary parking signal so that the set output amount of brake fluid flows into the front right wheel cylinder 205;

[0106] The front left wheel cylinder 204 is used to receive the inflow of brake fluid of a set output amount and maintain the braking pressure of the vehicle's left front wheel at a first set pressure value.

[0107] The front right wheel cylinder 205 is used to receive the inflow of brake fluid of a set output amount and maintain the braking pressure of the right front wheel of the vehicle at a first set pressure value.

[0108] In this embodiment, when the master cylinder 103 responds to the first working signal and delivers a set output amount of brake fluid to the front wheel brake module 104 and the rear wheel brake module 105, the first inlet valve 201 and the second inlet valve 202, having received the auxiliary parking signal, will first open. Then, through the front wheel return pump 203, which is originally used for brake fluid return, the brake fluid will be drawn to the inlet of the first inlet valve 201 and the inlet of the second inlet valve 202, so that the brake fluid flows into the front left wheel cylinder 204 and the front right wheel cylinder 205. Subsequently, the front left wheel cylinder 204 and the front right wheel cylinder 205 will increase the braking pressure proportionally according to the set output amount of brake fluid, until the braking pressure of the left front wheel and the right front wheel of the vehicle is raised to the first set pressure value with the help of this input brake fluid. After ensuring that the braking force provided by the front wheels of the vehicle can stabilize the vehicle body and prevent it from rolling, the braking pressure will be kept unchanged at the first set pressure value, thereby achieving the effect of assisting the user in parking.

[0109] In some embodiments, when the braking pressure reaches a first set pressure value, the anti-lock braking control module 101 also generates a pressurization completion signal and sends the signal to the first inlet valve 201 and the second inlet valve 202. In response to the pressurization completion signal, the first inlet valve 201 and the second inlet valve 202 close the valves to block the backflow of brake fluid, thereby preventing the braking pressure of the front left wheel cylinder 204 and the front right wheel cylinder 205 from decreasing due to brake fluid leakage.

[0110] Similar to the execution details of the front wheel braking module 104, the specific braking process of the rear wheel braking module 105 in this embodiment of the application when it receives the auxiliary parking signal will be given below.

[0111] Figure 3This is a schematic diagram of the structure of a rear wheel braking module 105 provided in an embodiment of this application. In one possible implementation, the rear wheel braking module 105 includes: a third inlet valve 206, a fourth inlet valve 207, a rear wheel return pump 208, a rear left wheel cylinder 209, and a rear right wheel cylinder 210; wherein, the second outlet of the solenoid valve 103 is connected to the inlet of the third inlet valve 206 and the inlet of the fourth inlet valve 207 respectively; the rear wheel outlet of the one-way valve group 106 is connected to the inlet of the rear wheel return pump 208; the outlet of the rear wheel return pump 208 is connected to the inlet of the third inlet valve 206 and the inlet of the fourth inlet valve 207 respectively; the outlet of the third inlet valve 206 is connected to the inlet of the rear left wheel cylinder 209; the outlet of the fourth inlet valve 207 is connected to the inlet of the rear right wheel cylinder 210; and the rear wheel return pump 208 is mechanically connected to the front wheel return pump 203 via a drive shaft.

[0112] The rear wheel return pump 208 is used to draw a set output amount of brake fluid from the master cylinder 102 to the inlet of the third inlet valve 206 and the inlet of the fourth inlet valve 207 in response to the auxiliary parking signal.

[0113] The third inlet valve 206 is used to open the valve in response to the auxiliary parking signal so that the set output amount of brake fluid flows into the rear left wheel cylinder 209;

[0114] The fourth inlet valve 207 is used to open the valve in response to the auxiliary parking signal so that the set output amount of brake fluid flows into the rear right wheel cylinder 210;

[0115] The rear left wheel cylinder 209 is used to receive the brake fluid inflow of a set output amount and maintain the braking pressure of the vehicle's left rear wheel at a first set pressure value.

[0116] The rear right wheel cylinder 210 is used to receive the inflow of brake fluid of a set output amount and maintain the braking pressure of the right rear wheel of the vehicle at a first set pressure value.

[0117] In this embodiment, similar to the front wheel brake module 104, when the master cylinder 103 responds to the first working signal and delivers a set output amount of brake fluid to the front wheel brake module 104 and the rear wheel brake module 105, the third inlet valve 206, the fourth inlet valve 207, the rear wheel return pump 208, the rear left wheel cylinder 209, and the rear right wheel cylinder 210, which receive the auxiliary parking signal, will also perform corresponding actions. Since the device actions of the rear wheel brake module 105 in this part are completely consistent with those of the front wheel brake module 104, all device action details can be referred to the relevant details of the front wheel brake module 104. Therefore, its specific control logic and device actions will not be described in detail.

[0118] In addition to assisting users in parking, the ABS system in this embodiment can also provide further braking functions based on the user's subsequent actions (such as a handbrake alarm function to prevent the vehicle from rolling away when the user leaves the vehicle without engaging the handbrake), to meet the diverse needs of users.

[0119] As one possible implementation method, please refer to Figure 4 This is a schematic diagram of the brake fluid flow direction when an anti-lock braking system (ABS) performs a handbrake alarm function, as provided in an embodiment of this application. When further performing the handbrake alarm function, the ABS control module 101 is also used to, after sending an auxiliary parking signal, respond to the driver's seatbelt being unlocked or the driver's side door being opened, and the handbrake not being disengaged, to obtain the vehicle's real-time slope and real-time load.

[0120] The anti-lock braking control module 101 is also used to send a third working signal to the master cylinder 102 and to send a handbrake alarm signal to the front wheel brake module 104 and the rear wheel brake module 105. The third working signal includes real-time slope and real-time load.

[0121] The master cylinder 102 is also used to respond to a third working signal and output the set increment of brake fluid corresponding to the real-time slope and real-time load based on the mapping relationship between the slope, load and brake fluid increment.

[0122] The front wheel braking module 104 is also used to maintain the braking pressure of the front wheels of the vehicle at a second set pressure value by setting the output amount and setting the increment of brake fluid in response to the handbrake alarm signal.

[0123] The rear wheel braking module 105 is also used to maintain the braking pressure of the vehicle's rear wheels at a second set pressure value by setting the output amount and setting the increment of brake fluid in response to a handbrake alarm signal.

[0124] In this embodiment, it is uncertain how long it will take for a user to return to the vehicle and cancel the ABS parking assist function after parking. Prolonged use of the ABS system for braking could lead to two problems: first, the anti-lock braking control module 101 might drain the vehicle's battery; second, maintaining high braking pressure for an extended period could cause deformation of vulnerable components such as valves and wheel cylinders in the ABS system. In this situation, using the handbrake to maintain parking is more suitable than using the ABS system. Therefore, it is necessary to promptly issue an alarm message upon detecting a potential user exiting the vehicle, prompting the user to engage the handbrake.

[0125] Meanwhile, since users have the ability to operate the vehicle at any time while in the vehicle, the first set pressure value output by the vehicle according to the actual travel of the brake pedal only needs to be just enough to prevent the vehicle from rolling away; when the load on the vehicle changes due to loading goods or passengers getting on, the user only needs to press the brake pedal further to increase the braking pressure, which can prevent the vehicle from rolling away again.

[0126] However, when the user leaves the vehicle, any change in vehicle load due to loading goods, passengers boarding, etc., may cause the gravitational force to exceed the vehicle's current first set pressure value, causing the vehicle to roll. At this time, because the user has left the vehicle, they cannot press the brake pedal again to increase the braking pressure, making it difficult to prevent the rolling phenomenon in time. Therefore, the idea of ​​maintaining the braking pressure at the first set pressure value when the user leaves the vehicle is no longer reliable. The anti-lock braking control module 101 needs to calculate an additional value of brake fluid output based on the vehicle's real-time load and real-time slope to maintain a sufficient braking pressure to stabilize the vehicle, so that even if the handbrake is not engaged during the user's absence, the vehicle will not roll due to insufficient braking pressure provided by the ABS system.

[0127] Because the ABS system has temporarily cut off the return path of brake fluid from the front wheel brake module 104 and rear wheel brake module 105 to the master cylinder 102 during assisted parking by switching the valve core of the solenoid valve 103 and restricting the flow direction of the one-way valve group 106. Therefore, if the master cylinder 102 continues to output brake fluid in response to the control signal of the anti-lock braking control module 101, it will only continuously increase the braking pressure provided by the front wheel brake module 104 and rear wheel brake module 105. This also ensures that the braking pressure can be increased from the first set pressure value to the second set pressure value.

[0128] The following is the complete process by which the ABS system increases the braking pressure from the first set pressure value to the second set pressure value:

[0129] First, when the anti-lock braking system (ABS) module 101 detects that the driver's seatbelt is unlocked or the driver's side door is opened, it assumes that the user may be getting out of the vehicle and needs to intervene through the ABS system to further increase braking pressure. Depending on the vehicle model or vehicle control system, other methods for determining whether the user has left the vehicle may include: the vehicle engine being turned off, the door being closed remotely by the Bluetooth key, or the vehicle's motion sensors detecting a movement signal from the driver's seat leaving the vehicle.

[0130] When the anti-lock braking control module 101 determines that the ABS system needs to brake, it also needs to acquire real-time slope and load data collected by vehicle sensors to provide further judgment for sending relevant control signals. Real-time slope data can be obtained through various means, including but not limited to: vehicle height and tilt angle data monitored by the vehicle's own tilt sensors; road slope data calculated from road information and vehicle position information obtained from the Global Positioning System (GPS); and vehicle driving slope calculated from linear acceleration and angular velocity output by the inertial measurement unit (IMU). Real-time load data can be obtained through various means, including but not limited to: data measured by load sensors installed in the vehicle's suspension system; pressure data output by hydraulic sensors in the vehicle's hydraulic system; and load data indirectly calculated from real-time speed information output by the IMU and engine output torque.

[0131] Subsequently, having acquired the vehicle's real-time slope and load, the anti-lock braking control module 101 calculates the increase in brake fluid that the master cylinder 102 should pump this time (i.e., the set increment) based on the pre-configured correspondence between slope, load, and brake fluid increment. Then, the anti-lock braking control module 101 sends a second working signal carrying this set increment data to the master cylinder 102 and a handbrake alarm signal to the front wheel brake module 104 and the rear wheel brake module 105. The master cylinder 102 outputs the set increment of brake fluid according to the second working signal. The front wheel brake module 104 and the rear wheel brake module 105 then apply a second set pressure value to the front and rear wheels of the vehicle based on the newly added set increment of brake fluid and the originally input set output amount of brake fluid, to maintain the vehicle's stability and prevent it from slipping under the current load and slope conditions.

[0132] In some embodiments, the anti-lock braking control module 101 can also send a handbrake alarm signal to the vehicle instrument panel, on-board computer and other devices to remind the user that the handbrake was not engaged when leaving the vehicle through text prompts, sound broadcasts and other means, so that the user can make timely corrections after noticing this operational error.

[0133] In some embodiments, the anti-lock braking control module 101 can also directly control the solenoid valve 103 to close the first and second outlets and connect the third outlet when it detects that the user is about to get off the vehicle and has not engaged the handbrake, even when the user has not used the ABS system for assisted parking. This is done by using the solenoid valve 103 and the one-way valve group 106 to limit the backflow of brake fluid. At the same time, it commands the master cylinder 102 to output brake fluid to the front wheel brake module 104 and the rear wheel brake module 105 according to the real-time slope and real-time load, thereby generating a second set pressure value of braking pressure. This allows the ABS system to perform the handbrake alarm function even when assisted parking has not been performed.

[0134] The following uses the front wheel braking module 104 in this embodiment as an example to explain in detail the process of increasing the braking pressure of the vehicle ABS system to the second set pressure value.

[0135] Figure 5 This is a schematic diagram of the brake fluid flow direction when the front wheel brake module 104 performs the handbrake alarm function according to an embodiment of this application. As a possible implementation, the front wheel return pump 203 is also used to draw brake fluid of a set output amount and a set increment to the inlet of the first inlet valve 201 and the inlet of the second inlet valve 202 in response to the handbrake alarm signal;

[0136] The first inlet valve 201 is also used to open the valve in response to the handbrake alarm signal so that the set output amount of brake fluid flows into the front left wheel cylinder 204;

[0137] The second inlet valve 202 is also used to open the valve in response to the handbrake alarm signal so that the set output amount of brake fluid flows into the front right wheel cylinder 205;

[0138] The front left wheel cylinder 204 is also used to receive a set increment of brake fluid inflow and maintain the braking pressure of the vehicle's left front wheel at a second set pressure value by using the set increment and set output amount of brake fluid.

[0139] The front right wheel cylinder 205 is also used to receive a set increment of brake fluid inflow and maintain the braking pressure of the vehicle's right front wheel at a second set pressure value by using the set increment and set output amount of brake fluid.

[0140] In this embodiment, when the vehicle's master cylinder 102 outputs a predetermined increment of brake fluid to increase braking pressure, the first inlet valve 201 and the second inlet valve 202, upon receiving a handbrake alarm signal, will open. Simultaneously, the front wheel return pump 203 will also start operating, drawing the newly input predetermined increment of brake fluid into the inlets of the two inlet valves. Since the front left wheel cylinder 204 and the front right wheel cylinder 205 have already maintained a first predetermined pressure value by receiving the predetermined output amount of brake fluid, when the predetermined increment of brake fluid flows in through the first inlet valve 201 and the second inlet valve 202, it is necessary to increase the braking pressure from the first predetermined pressure value to the second predetermined pressure value according to the predetermined increment of brake fluid. This ensures that when the user leaves the vehicle and the handbrake is not engaged, the front wheel braking module 104 of the ABS system maintains the braking pressure of the vehicle's front wheels at the second predetermined pressure value.

[0141] It should be understood that since the device actions performed by the rear wheel brake module 105 in response to the handbrake alarm signal are exactly the same as those of the front wheel brake module 104, all device action details can be referred to the relevant details of the front wheel brake module 104. Therefore, its specific control logic and device actions will not be described in detail.

[0142] When a user notices that the handbrake is not engaged and returns to engage it, the vehicle can add control logic related to handbrake engagement and execute corresponding actions based on this control logic to stop using the ABS system to continue braking and avoid hindering the vehicle from starting and driving.

[0143] Figure 6 This is a schematic diagram of the brake fluid flow direction when the anti-lock braking system detects the handbrake being engaged, provided in an embodiment of this application. As one possible implementation, the anti-lock braking control module 101 is further configured to, after sending a handbrake alarm signal, in response to the handbrake being engaged, send a fourth operating signal to the master cylinder 102, and send a handbrake engagement signal to the solenoid valve 103, the front wheel brake module 104, and the rear wheel brake module 105;

[0144] The master cylinder 102 is also used to draw brake fluid through the outlet of the master cylinder 102 in response to the fourth working signal.

[0145] The solenoid valve 103 is also used to connect the first liquid outlet and the second liquid outlet in response to the handbrake opening signal, and to close the third liquid outlet.

[0146] The front wheel brake module 104 is also used to respond to the handbrake release signal to allow the brake fluid to flow back along the first inlet of the front wheel brake module 104 until the braking pressure of the front wheels of the vehicle is reduced to zero.

[0147] The rear wheel brake module 105 is also used to respond to the handbrake release signal to allow brake fluid to flow back along the first inlet of the rear wheel brake module 105 until the braking pressure of the vehicle's rear wheels returns to zero.

[0148] In this embodiment, when a user returns to the vehicle after leaving and engages the handbrake, using the ABS system for braking would conflict with the parking brake function. Therefore, the braking effect of the ABS system needs to be canceled promptly. Specifically, when the anti-lock braking control module 101 detects the handbrake is engaged, it first sends a fourth working signal to the master cylinder 102 to command it to re-draw brake fluid. It also sends a handbrake engagement signal to the solenoid valve 103, the front wheel brake module 104, and the rear wheel brake module 105, commanding the solenoid valve 103 to keep its first and second outlets normally open and its third outlet normally closed, thus allowing brake fluid to flow back. Even though the brake fluid no longer flows through the pipeline containing the one-way valve assembly 106, it flows back to the master cylinder 102 via the conventional anti-lock braking path. Since the brake fluid has flowed back to the master cylinder 102, the braking pressure output by the front wheel brake module 104 and the rear wheel brake module 105 will also return to zero, transferring the braking operation to the vehicle's handbrake.

[0149] Figure 7This is a schematic diagram of the brake fluid flow direction of a front wheel brake module 104 when it receives a handbrake activation signal, according to an embodiment of this application. As one possible implementation, the first inlet valve 201 is also used to open the valve in response to the handbrake activation signal, so that brake fluid with a set increment and a set output amount flows back from the front left wheel cylinder 204 to the brake master cylinder 102.

[0150] The second inlet valve 202 is also used to open the valve in response to the handbrake opening signal so that the brake fluid with the set increment and set output amount flows back from the front right wheel cylinder 205 to the brake master cylinder 102.

[0151] The front left wheel cylinder 204 is also used to reduce the braking pressure of the vehicle's left front wheel to zero after the brake fluid has completely returned.

[0152] The front right wheel cylinder 205 is also used to reduce the braking pressure of the vehicle's right front wheel to zero after the brake fluid has completely returned.

[0153] In this embodiment, after receiving the handbrake release signal from the anti-lock braking control module 101, the first inlet valve 201 and the second inlet valve 202 are opened to allow brake fluid backflow. Subsequently, due to the brake fluid backflow, the brake pressure of the left front wheel cylinder 204 and the right front wheel cylinder 205 is reduced to zero, stopping the braking so that the handbrake can take over the parking brake from the ABS system.

[0154] It should be understood that since the device actions performed by the rear wheel brake module 105 in response to the handbrake release signal are exactly the same as those of the front wheel brake module 104, all device action details can be referred to the relevant details of the front wheel brake module 104. Therefore, its specific control logic and device actions will not be described in detail again.

[0155] In some embodiments, after the left wheel cylinder 204 and the front right wheel cylinder 205 bring the braking pressure of the vehicle's front wheels to zero, the anti-lock braking control module 101 can further send a braking stop signal to the first inlet valve 201 and the second inlet valve 202 to control the valves to close, preventing the brake fluid from re-entering the front left wheel cylinder 204 and the front right wheel cylinder 205 when braking is not required.

[0156] In some embodiments, additional control logic may be added to the ABS system for other situations where braking needs to be canceled, such as canceling wheel braking in a timely manner when the user needs to drive the vehicle normally.

[0157] Figure 8This is a schematic diagram of the brake fluid flow direction detected by an anti-lock braking system (ABS) when a vehicle starts, provided in an embodiment of this application. The ABS control module 101 is further configured to, after sending an auxiliary parking signal or a handbrake alarm signal, respond to the following conditions: the actual travel of the accelerator pedal is greater than a second set travel, the engine output torque is greater than a set starting torque, and no handbrake release signal has been sent after the handbrake alarm signal; send a fifth working signal to the master cylinder 102 and a hill start signal to the solenoid valve 103, the front wheel brake module 104, and the rear wheel brake module 105.

[0158] The master cylinder 102 is also used to draw brake fluid through the inlet of the master cylinder 102 in response to the fifth working signal.

[0159] The solenoid valve 103 is also used to connect the first liquid outlet and the second liquid outlet in response to the steep slope start signal, and to close the third liquid outlet.

[0160] The front wheel brake module 104 is also used to respond to a steep hill start signal by causing the brake fluid to flow back along the first inlet of the front wheel brake module 104 until the braking pressure of the front wheels of the vehicle is reduced to zero.

[0161] The rear wheel brake module 105 is also used to respond to a steep slope start signal by causing brake fluid to flow back along the first inlet of the rear wheel brake module 105 until the braking pressure of the vehicle's rear wheels returns to zero.

[0162] In this embodiment, when the anti-lock braking control module 101 has sent an auxiliary parking signal or a handbrake alarm signal but has not yet sent a handbrake release signal, and the vehicle's engine output torque is greater than or equal to the set starting torque, the vehicle's ABS system already has a certain braking pressure due to the brake fluid output from the master cylinder 102. Since no handbrake release signal has been sent, the brake fluid in the wheel cylinders has not yet returned, meaning the wheel cylinder braking pressure is not zero. Furthermore, the vehicle has reached the conditions for normal road driving and no longer needs to apply the brakes. Brake fluid return is necessary to ensure unimpeded vehicle movement. Therefore, a fifth working signal is sent to the master cylinder 102, and a hill start signal is sent to the vehicle's solenoid valve 103, front wheel brake module 104, and rear wheel brake module 105 to enable brake fluid return and reduce the braking pressure of the front and rear wheels to zero, preventing the vehicle from being hindered from normal driving due to the presence of braking pressure.

[0163] It should be understood that the set starting torque can also be pre-configured as a mapping relationship with the slope and load, rather than a fixed threshold (in a setting increment configuration similar to brake fluid). This allows the set starting torque to be dynamically adjusted according to the real-time slope and load of the vehicle, so that the braking can be canceled when the vehicle can drive normally up a steep slope, without causing dangerous situations such as the vehicle rolling backward or colliding due to the engine's output torque being less than the vehicle load.

[0164] To further illustrate the hill start function provided by the ABS system and the working details of related components in the embodiments of this application, the front wheel braking module 104 will be described in detail below as an example.

[0165] Figure 9 This is a schematic diagram of the brake fluid flow direction of a front wheel brake module 104 when receiving a steep slope start signal, according to an embodiment of this application. As one possible implementation, the first inlet valve 201 is also used to open the valve in response to the steep slope start signal, allowing the brake fluid to flow back from the front left wheel cylinder 204 to the brake master cylinder 102;

[0166] The second inlet valve 202 is used to open the valve in response to the steep slope start signal, so that the brake fluid flows back from the front right wheel cylinder 205 to the brake master cylinder 102.

[0167] The front left wheel cylinder 204 is used to reduce the braking pressure of the vehicle's left front wheel to zero after the brake fluid has completely returned.

[0168] The front right wheel cylinder 205 is used to reduce the braking pressure of the vehicle's right front wheel to zero after the brake fluid has completely returned.

[0169] In this embodiment, when the anti-lock braking control module 101 sends a steep slope start signal, the front wheel braking module 104 controls the opening of the first inlet valve 201 and the second inlet valve 202 to allow brake fluid to flow back from the front left wheel cylinder 204 and the front right wheel cylinder 205 to the master cylinder 102, thereby reducing the braking pressure of the left and right front wheels of the vehicle to zero, so that the vehicle can start normal driving.

[0170] It should be understood that since the device actions performed by the rear wheel braking module 105 in response to the steep slope start signal are exactly the same as those of the front wheel braking module 104, all device action details can be referred to the relevant details of the front wheel braking module 104. Therefore, its specific control logic and device actions will not be described in detail again.

[0171] In some embodiments, the check valve assembly 106 is crucial for preventing brake fluid backflow and maintaining brake pressure because it restricts the flow direction of brake fluid. Beyond restricting backflow through the check valve assembly 106, the ABS system used in this embodiment shares a portion of piping for multiple functions. If flow direction restrictions are not applied to these shared piping when performing a particular function, brake fluid flow may become disordered, preventing the function from functioning correctly. Therefore, more check valves can be added to further restrict the flow direction of the brake fluid.

[0172] Figure 10This is a schematic diagram of the structure of an anti-lock braking system (ABS) after adding multiple sets of one-way valves, as provided in an embodiment of this application. The system further includes: a first one-way valve 301, a second one-way valve 302, a third one-way valve 303, a fourth one-way valve 304, a fifth one-way valve 305, and a sixth one-way valve 306. The inlet of the first one-way valve 301 is connected to the outlet of the first inlet valve 201, and the outlet of the first one-way valve 301 is also connected to the inlet of the first inlet valve 201. The inlet of the second one-way valve 302 is connected to the outlet of the second inlet valve 202, and the outlet of the second one-way valve 302 is also connected to the inlet of the second inlet valve 202. The inlet of the third one-way valve 303 is connected to the outlet of the third inlet valve 206. The outlet of the third check valve 303 is connected to the inlet of the third inlet valve 206; the inlet of the fourth check valve 304 is connected to the outlet of the fourth inlet valve 207, and the outlet of the fourth check valve 304 is connected to the inlet of the fourth inlet valve 207; the inlet of the fifth check valve 305 is connected to the inlet of the front wheel return oil pump 203, and the outlet of the fifth check valve 305 is connected to the outlet of the front wheel return oil pump 203; the inlet of the sixth check valve 306 is connected to the inlet of the rear wheel return oil pump 208, and the outlet of the sixth check valve 306 is connected to the outlet of the rear wheel return oil pump 208.

[0173] The first check valve 301, the second check valve 302, the third check valve 303, and the fourth check valve 304 are all used to prevent brake fluid from flowing back along the branch where the first check valve 301, the second check valve 302, the third check valve 303, and the fourth check valve 304 are located when the first and second outlets of the solenoid valve 103 are normally open, the third outlet is normally closed, and the brake fluid flows back to the master cylinder 102 along the first inlet valve 201, the second inlet valve 202, the third inlet valve 206, and the fourth inlet valve 207; or, when the first and second outlets of the solenoid valve 103 are normally open and the third outlet is normally closed, prevent the brake fluid from flowing back along the path opposite to the preset flow direction.

[0174] The fifth check valve 305 and the sixth check valve 306 are both used to prevent brake fluid from flowing back along a path opposite to the preset flow direction when the first and second outlets of the solenoid valve 103 are kept open and the third outlet is kept closed.

[0175] The one-way valve assembly 106 includes a seventh one-way valve 307 and an eighth one-way valve 308, wherein the third outlet of the solenoid valve 103 is connected to the inlet of the seventh one-way valve 307 and the inlet of the eighth one-way valve 308, respectively; the outlet of the seventh one-way valve 307 is connected to the inlet of the front circulation oil pump 203; and the outlet of the eighth one-way valve 308 is connected to the inlet of the rear circulation oil pump 208.

[0176] The seventh check valve 307 is used to prevent brake fluid flowing from the front left wheel cylinder 204 and the front right wheel cylinder 205 into the rear left wheel cylinder 209 and the rear right wheel cylinder 210 when the first and second outlet ports of the solenoid valve 103 are kept open and the third outlet port is kept closed.

[0177] The eighth one-way valve 308 is used to prevent brake fluid flowing to the rear left wheel cylinder and the rear right wheel cylinder from flowing into the front left wheel cylinder 204 and the front right wheel cylinder 205 when the first and second outlets of the solenoid valve 103 are normally open and the third outlet is normally closed.

[0178] In this embodiment, by connecting the first one-way valve 301 in parallel with the first inlet valve 201, wherein the inlet of the first one-way valve 301 is connected to the outlet of the first inlet valve 201, and the outlet of the first one-way valve 301 is connected to the inlet of the first inlet valve 201, and by similarly connecting the second one-way valves 302 to the fourth one-way valve 304 in parallel with the other three inlet valves, it is possible to achieve the effect of additional brake fluid flow through the four branches containing the first one-way valves 301 to the fourth one-way valve 304 when the brake master cylinder 102 receives the fourth or fifth working signal and begins to pump back fluid. Compared to the method of relying solely on the inlet valves to pump back brake fluid, adding one-way valves can obviously further increase the backflow rate and help shorten the brake fluid backflow time.

[0179] Meanwhile, the inlet of the fifth one-way valve 305 is connected to the inlet of the front wheel return pump 203, and the outlet is connected to the outlet of the front wheel return pump 203. This connection method allows the brake fluid to flow directly into the front left wheel cylinder 204 and the front right wheel cylinder 205 along the branch where the fifth one-way valve 305 is located when the braking pressure output by the ABS system is low. This achieves the effect of pressurization without starting the return pump (because at this time the pressure value at the inlet of the fifth one-way valve 305 is greater than that at the outlet, there is no risk that the brake fluid in the front left wheel cylinder 204 and the front right wheel cylinder 205 will flow back into the master cylinder 102 due to the opening of the first inlet valve 201 and the second inlet valve 202). At the same time, even if the braking pressure of the ABS system is high at this time, the pressure value at the outlet of the fifth one-way valve 305 is greater than that at the inlet, and its one-way valve nature can still prevent the brake fluid flowing into the wheel cylinder from flowing back, so that the ABS system can complete the pressurization normally through the operation of the front wheel return pump 203.

[0180] It should be understood that the connection method between the sixth check valve 306 and the rear circulation oil pump 208, as well as the function of this connection method, are similar to those of the fifth check valve 305 mentioned above, so they will not be described again here.

[0181] As for the seventh one-way valve 307 and the eighth one-way valve 308 included in the one-way valve group 106, their main function is to prevent functional malfunctions such as "brake fluid allocated to the front left wheel cylinder 204 flowing into the rear left wheel cylinder" by connecting the fluid outlet to the front wheel return pump 203 and the rear wheel return pump 208 respectively when the ABS system is performing the anti-lock braking function normally, thus ensuring that the anti-lock braking function and auxiliary parking function of the ABS system can be performed normally.

[0182] It should be understood that the "preventing brake fluid from flowing back along a path opposite to the preset flow direction" mentioned above refers to the original flow direction of the brake fluid designed for the anti-lock braking function in the ABS system. Since this preset flow direction is related to the piping connections of the ABS system, and the ABS system has many possible connection methods besides those listed in the embodiments of this application, no specific preset flow direction is limited; only its meaning is explained in detail.

[0183] The above description is merely a preferred embodiment of this specification and is not intended to limit this specification. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this specification should be included within the scope of protection of this specification.

Claims

1. An anti-lock braking system, characterized in that, The anti-lock braking system includes: The system includes an anti-lock braking system (ABS) control module, a master cylinder, a solenoid valve, a front wheel brake module, a rear wheel brake module, and a check valve assembly. The ABS control module is electrically connected to the master cylinder, the solenoid valve, the front wheel brake module, and the rear wheel brake module. The outlet of the master cylinder is connected to the inlet of the solenoid valve. The first outlet of the solenoid valve is connected to the first inlet of the front wheel brake module. The second outlet of the solenoid valve is connected to the first inlet of the rear wheel brake module. The third outlet of the solenoid valve is connected to the inlet of the check valve assembly. The front wheel outlet of the check valve assembly is connected to the second inlet of the front wheel brake module, and the rear wheel outlet of the check valve assembly is connected to the second inlet of the rear wheel brake module. The first and second outlets of the solenoid valve are normally open, while the third outlet is normally closed. Both the front and rear wheel braking modules include parallel return oil pumps and two sets of sequentially connected inlet valves and wheel cylinders. The first and second outlets of the solenoid valve are respectively connected to the inlets of the corresponding two inlet valves, and the outlet of the return oil pump is connected to the inlets of the corresponding two inlet valves. The two return oil pumps are mechanically connected via a drive shaft. The one-way valve group includes a seventh one-way valve and an eighth one-way valve. The third outlet of the solenoid valve is respectively connected to the inlets of the seventh and eighth one-way valves. The outlet of the seventh one-way valve is connected to the inlet of one of the return oil pumps, and the outlet of the eighth one-way valve is connected to the inlet of the other return oil pump. The anti-lock braking control module is configured to, in response to a vehicle speed greater than a speed threshold and an actual brake pedal travel greater than or equal to a first preset travel, send a first working signal to the master cylinder and a braking signal to the front wheel braking module and the rear wheel braking module; or, in response to a vehicle speed of zero and an actual brake pedal travel greater than or equal to the first preset travel, send a second working signal to the master cylinder and an auxiliary parking signal to the solenoid valve, the front wheel braking module, and the rear wheel braking module, wherein the first working signal and the second working signal include the actual brake pedal travel; The master cylinder is used to respond to the first working signal or the second working signal, and output a set output amount of brake fluid corresponding to the actual travel of the brake pedal, based on the mapping relationship between the brake pedal travel and the brake fluid output amount. The solenoid valve is used to close the first and second outlets of the solenoid valve and connect the third outlet in response to the auxiliary parking signal. The front wheel braking module is used to receive the set output amount of brake fluid in response to the braking signal to perform a preset anti-lock braking function on the front wheels of the vehicle; or, in response to the auxiliary parking signal, maintain the braking pressure of the front wheels of the vehicle at a first set pressure value through the set output amount of brake fluid. The rear wheel braking module is used to respond to the braking signal and receive the set output amount of brake fluid to perform the preset anti-lock braking function on the rear wheels of the vehicle; or, in response to the auxiliary parking signal, to maintain the braking pressure of the rear wheels of the vehicle at the first set pressure value through the set output amount of brake fluid.

2. The system according to claim 1, characterized in that, The anti-lock braking control module is also used to, after sending the auxiliary parking signal, respond to the driver's seat belt not being locked or the driver's side door being opened and the handbrake not being released, to obtain the vehicle's real-time slope and real-time load. The anti-lock braking control module is also used to send a third working signal to the master cylinder and a handbrake alarm signal to the front wheel brake module and the rear wheel brake module. The third working signal includes the real-time slope and the real-time load. The master cylinder is also used to respond to the third working signal and, based on the mapping relationship between slope, load and brake fluid increment, output the set increment of brake fluid corresponding to the real-time slope and real-time load. The front wheel braking module is also used to respond to the handbrake alarm signal by maintaining the braking pressure of the front wheels of the vehicle at a second set pressure value through the set output amount of brake fluid and the set increment of brake fluid. The rear wheel braking module is also used to respond to the handbrake alarm signal by maintaining the braking pressure of the vehicle's rear wheels at the second set pressure value using the set output amount of brake fluid and the set increment of brake fluid.

3. The system according to claim 2, characterized in that, The anti-lock braking control module is also used to, after sending the handbrake alarm signal, in response to the handbrake being opened, send a fourth working signal to the master cylinder and send a handbrake opening signal to the solenoid valve, the front wheel brake module and the rear wheel brake module; The master cylinder is also used to draw brake fluid through the outlet of the master cylinder in response to the fourth working signal. The solenoid valve is also used to respond to the handbrake opening signal by connecting the first outlet and the second outlet of the solenoid valve and closing the third outlet. The front wheel braking module is also used to respond to the handbrake release signal by causing the brake fluid to flow back along the first inlet of the front wheel braking module until the braking pressure of the front wheels of the vehicle returns to zero. The rear wheel braking module is also used to respond to the handbrake release signal by causing the brake fluid to flow back along the first inlet of the rear wheel braking module until the braking pressure of the vehicle's rear wheels returns to zero.

4. The system according to claim 3, characterized in that, The anti-lock braking control module is also used to, after sending the auxiliary parking signal or the handbrake alarm signal, respond to the actual travel of the accelerator pedal being greater than the second set travel and the engine output torque being greater than the set starting torque, and without sending the handbrake release signal after the handbrake alarm signal, send a fifth working signal to the master cylinder and send a steep slope start signal to the solenoid valve, the front wheel brake module and the rear wheel brake module; The master cylinder is also used to draw brake fluid through the outlet of the master cylinder in response to the fifth working signal. The solenoid valve is also used to respond to the steep slope start signal by connecting the first outlet and the second outlet of the solenoid valve and closing the third outlet. The front wheel braking module is also used to respond to the steep slope start signal by causing the brake fluid to flow back along the first inlet of the front wheel braking module until the braking pressure of the front wheels of the vehicle returns to zero. The rear wheel braking module is also used to respond to the steep slope start signal by causing the brake fluid to flow back along the first inlet of the rear wheel braking module until the braking pressure of the vehicle's rear wheels returns to zero.

5. The system according to claim 4, characterized in that, The front wheel braking module includes: a first inlet valve, a second inlet valve, a front wheel return pump, a front left wheel cylinder, and a front right wheel cylinder; wherein, the first outlet of the solenoid valve is connected to the inlet of the first inlet valve and the inlet of the second inlet valve, the front wheel outlet of the one-way valve assembly is connected to the inlet of the front wheel return pump, the outlet of the front wheel return pump is connected to the inlet of the first inlet valve and the inlet of the second inlet valve, the outlet of the first inlet valve is connected to the inlet of the front left wheel cylinder, and the outlet of the second inlet valve is connected to the inlet of the front right wheel cylinder; The front wheel return pump is used to respond to the auxiliary parking signal by drawing the set output amount of brake fluid from the master cylinder to the inlet of the first inlet valve and the inlet of the second inlet valve. The first inlet valve is used to open the valve in response to the auxiliary parking signal, so that the set output amount of brake fluid flows into the front left wheel cylinder; The second inlet valve is used to open the valve in response to the auxiliary parking signal, so that the set output amount of brake fluid flows into the front right wheel cylinder; The front left wheel cylinder is used to receive the brake fluid inflow of the set output amount and maintain the braking pressure of the vehicle's left front wheel at the first set pressure value. The front right wheel cylinder is used to receive the brake fluid inflow of the set output amount and maintain the braking pressure of the right front wheel of the vehicle at the first set pressure value.

6. The system according to claim 5, characterized in that, The rear wheel braking module includes: a third inlet valve, a fourth inlet valve, a rear wheel return pump, a rear left wheel cylinder, and a rear right wheel cylinder; wherein, the second outlet of the solenoid valve is connected to the inlet of the third inlet valve and the inlet of the fourth inlet valve respectively; the rear wheel outlet of the one-way valve group is connected to the inlet of the rear wheel return pump; the outlet of the rear wheel return pump is connected to the inlet of the third inlet valve and the inlet of the fourth inlet valve respectively; the outlet of the third inlet valve is connected to the inlet of the rear left wheel cylinder; the outlet of the fourth inlet valve is connected to the inlet of the rear right wheel cylinder; and the rear wheel return pump is mechanically connected to the front wheel return pump via a drive shaft. The rear wheel return oil pump is used to respond to the auxiliary parking signal by drawing the set output amount of brake fluid from the master cylinder to the inlet of the third inlet valve and the inlet of the fourth inlet valve. The third inlet valve is used to open the valve in response to the auxiliary parking signal, so that the set output amount of brake fluid flows into the rear left wheel cylinder; The fourth inlet valve is used to open the valve in response to the auxiliary parking signal, so that the set output amount of brake fluid flows into the rear right wheel cylinder; The rear left wheel cylinder is used to receive the brake fluid inflow of the set output amount and maintain the braking pressure of the vehicle's left rear wheel at the first set pressure value. The rear right wheel cylinder is used to receive the brake fluid inflow of the set output amount and maintain the braking pressure of the right rear wheel of the vehicle at the first set pressure value.

7. The system according to claim 6, characterized in that, The system further includes: a first check valve, a second check valve, a third check valve, a fourth check valve, a fifth check valve, and a sixth check valve, wherein the inlet of the first check valve is connected to the outlet of the first inlet valve, and the outlet of the first check valve is connected to the inlet of the first inlet valve; the inlet of the second check valve is connected to the outlet of the second inlet valve, and the outlet of the second check valve is connected to the inlet of the second inlet valve; the inlet of the third check valve is connected to the outlet of the third inlet valve. The outlet of the third check valve is connected to the inlet of the third inlet valve; the inlet of the fourth check valve is connected to the outlet of the fourth inlet valve, and the outlet of the fourth check valve is connected to the inlet of the fourth inlet valve; the inlet of the fifth check valve is connected to the inlet of the front return oil pump, and the outlet of the fifth check valve is connected to the outlet of the front return oil pump; the inlet of the sixth check valve is connected to the inlet of the rear return oil pump, and the outlet of the sixth check valve is connected to the outlet of the rear return oil pump. The first check valve, the second check valve, the third check valve, and the fourth check valve are all used to ensure that when the first and second outlets of the solenoid valve are normally open and the third outlet is normally closed, and the brake fluid flows back to the master cylinder along the first inlet valve, the second inlet valve, the third inlet valve, and the fourth inlet valve, the brake fluid flows back along the branch where the first check valve, the second check valve, the third inlet valve, and the fourth inlet valve are located; or, when the first and second outlets of the solenoid valve are normally open and the third outlet is normally closed, the brake fluid is prevented from flowing back along a path opposite to the preset flow direction. The fifth check valve and the sixth check valve are both used to prevent brake fluid from flowing back along the path opposite to the preset flow direction when the first and second outlets of the solenoid valve are kept open and the third outlet is kept closed. The seventh one-way valve is used to prevent brake fluid flowing to the front left wheel cylinder and the front right wheel cylinder from flowing into the rear left wheel cylinder and the rear right wheel cylinder when the first and second outlets of the solenoid valve are normally open and the third outlet is normally closed. The eighth one-way valve is used to prevent brake fluid flowing to the rear left wheel cylinder and the rear right wheel cylinder from flowing into the front left wheel cylinder and the front right wheel cylinder when the first and second outlets of the solenoid valve are normally open and the third outlet is normally closed.

8. The system according to claim 5, characterized in that, The front wheel return pump is also used to respond to the handbrake alarm signal by drawing the set increment of brake fluid to the inlet of the first inlet valve and the inlet of the second inlet valve. The first inlet valve is also used to open the valve in response to the handbrake alarm signal, so that the set increment of brake fluid flows into the front left wheel cylinder; The second inlet valve is also used to open the valve in response to the handbrake alarm signal, allowing the set increment of brake fluid to flow into the front right wheel cylinder; The front left wheel cylinder is also used to receive the brake fluid inflow of the set increment, and to maintain the braking pressure of the vehicle's left front wheel at the second set pressure value by the brake fluid of the set increment and the brake fluid of the set output quantity. The front right wheel cylinder is also used to receive the brake fluid inflow of the set increment, and to maintain the braking pressure of the right front wheel of the vehicle at the second set pressure value by the brake fluid of the set increment and the brake fluid of the set output quantity.

9. The system according to claim 8, characterized in that, The first inlet valve is also used to open the valve in response to the handbrake opening signal so that the set output amount of brake fluid and the set increment of brake fluid flow back from the front left wheel cylinder to the master cylinder; The second inlet valve is also used to open the valve in response to the handbrake release signal, so that the set output amount of brake fluid and the set increment of brake fluid flow back from the front right wheel cylinder to the master cylinder; The front left wheel cylinder is also used to reduce the braking pressure of the vehicle's left front wheel to zero after the brake fluid has completely returned. The front right wheel cylinder is also used to reduce the braking pressure of the right front wheel of the vehicle to zero after the brake fluid has completely returned.

10. The system according to claim 9, characterized in that, The first inlet valve is also used to open the valve in response to the steep slope start signal, so that the set output amount of brake fluid and the set increment of brake fluid flow back from the front left wheel cylinder to the master cylinder; The second inlet valve is also used to open the valve in response to the steep slope start signal, so that the set output amount of brake fluid and the set increment of brake fluid flow back from the front right wheel cylinder to the master cylinder; The front left wheel cylinder is also used to reduce the braking pressure of the vehicle's left front wheel to zero after the brake fluid has completely returned. The front right wheel cylinder is also used to reduce the braking pressure of the right front wheel of the vehicle to zero after the brake fluid has completely returned.

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