Hydraulic antilock brake system and method with integrated high pressure accumulator

Abstract

This invention provides a hydraulic anti-lock braking system and method integrating a high-pressure accumulator, including a brake actuator, a high-pressure accumulator, a main hydraulic power source, and a pressure selection valve. The two inlets of the pressure selection valve are respectively connected to the outlet of the main hydraulic power source and the output fluid path of the high-pressure accumulator, and its outlet is connected to the inlet of the brake actuator. A brake fluid reservoir has its outlet connected to the inlet of the main hydraulic power source and its inlet connected to the outlet of the brake actuator. This invention improves system smoothness and braking responsiveness, optimizes system cost, and enhances hardware utilization.

Description

Technical Field

[0001] This invention relates to the field of vehicle braking system technology, and in particular to a hydraulic anti-lock braking system and method integrating a high-voltage accumulator. Background Technology

[0002] Anti-lock braking system (ABS) is a safety system that plays a crucial role in emergency braking of a vehicle. It is based on the electronic control system's high-frequency regulation of the hydraulic pressure at the brake actuator (i.e., the hydraulic actuator installed at the wheel to receive brake fluid and convert it into friction braking force), thereby effectively preventing the vehicle from losing steering ability or experiencing dangerous skidding due to wheel lock-up.

[0003] Traditional anti-lock braking systems (ABS) typically rely on a base brake pressure source and a hydraulic regulating module containing a return pump to achieve a high-frequency "pressure boost-pressure hold-pressure depressurization" cycle, thereby regulating wheel cylinder pressure. In this traditional architecture, the outlet of the master cylinder (directly connected to the driver's brake pedal) and the high-pressure outlet of the return pump are connected in parallel via a T-junction on the path leading to the brake actuator. However, this traditional architecture has significant flaws in the physical topology of the hydraulic lines, leading to the following problems in practical applications: Firstly, there is the issue of delayed decompression response. During the decompression phase, the traditional system discharges brake fluid into a very small low-pressure buffer chamber. The instantaneous influx of brake fluid causes a sharp increase in pressure inside this narrow chamber, preventing the remaining brake fluid from being discharged smoothly and resulting in a delayed response.

[0004] Secondly, there is the issue of high-frequency vibration in the brake pedal. During the pressurization phase, the intense hydraulic shock directly impacts the piston in the master cylinder, ultimately causing the driver's brake pedal to vibrate violently and frequently.

[0005] Third, the adjustment performance is limited. In extreme conditions such as long downhill slopes on icy or snowy roads or frequent switching between roads with high and low adhesion coefficients, which require the system to continuously and frequently trigger anti-lock braking, the adjustment performance of traditional anti-lock braking systems is insufficient, seriously threatening driving safety.

[0006] Fourth, the system has high costs and low hardware utilization. In traditional architectures, the anti-lock braking system's return pump is only activated in rare lock-up situations, remaining idle for extended periods, resulting in extremely low hardware utilization. Furthermore, new energy vehicles, lacking an engine vacuum source, must be equipped with expensive electronic vacuum pumps and vacuum tanks, leading to significant hardware redundancy and high costs.

[0007] Therefore, this application urgently needs to provide a hydraulic anti-lock braking system and method integrating a high-voltage accumulator to solve the above problems. Summary of the Invention

[0008] In view of the shortcomings of the prior art described above, the purpose of this invention is to provide a hydraulic anti-lock braking system and method integrating a high-voltage accumulator. This invention can greatly optimize the adjustment performance and system cost of the anti-lock braking system.

[0009] This invention provides a hydraulic anti-lock braking system integrating a high-voltage accumulator, including a braking actuator and further comprising: The system includes a high-pressure accumulator, a main hydraulic power source, and a pressure selection valve. The two inlets of the pressure selection valve are connected to the outlet of the main hydraulic power source and the output circuit of the high-pressure accumulator, respectively, and its outlet is connected to the inlet of the brake actuator. The brake fluid reservoir has its outlet connected to the inlet of the main hydraulic power source and its inlet connected to the outlet of the brake actuator.

[0010] Preferably, it further includes: A proportional control valve, the outlet of which is connected to one inlet of a pressure selector valve; The power booster pump has its inlet connected to the brake fluid reservoir, and its outlet connected in parallel with the high-pressure accumulator's inlet to the inlet of the proportional control valve.

[0011] Preferably, it also includes a normally open solenoid valve, the inlet of which is connected to the pipeline between the proportional regulating valve and the pressure selection valve, and the outlet of which is connected to the brake fluid reservoir.

[0012] Preferably, it further includes: Wheel speed sensor, which is installed on the wheel; The inlet control valve and the outlet control valve control the inlet and outlet of the brake actuator, respectively. The electronic control unit is electrically connected to the wheel speed sensor, the power booster pump, the proportional control valve, the normally open solenoid valve, the inlet control valve, and the outlet control valve.

[0013] Preferably, it also includes an accumulator pressure sensor, which is installed in a pipeline connected to the internal hydraulic pressure of the high-pressure accumulator, and the electronic control unit is electrically connected to the accumulator pressure sensor.

[0014] Preferably, it also includes a wheel cylinder pressure sensor, which is installed in the fluid inlet passage of the brake actuator, and the electronic control unit is electrically connected to the wheel cylinder pressure sensor.

[0015] This invention also provides a control method for a hydraulic anti-lock braking system integrating a high-voltage accumulator, applied to a hydraulic anti-lock braking system, the control method comprising the following steps: Signal acquisition steps: Acquire the wheel speed signal of the wheel; Pressure reduction control steps: When the wheel speed signal determines that the wheel meets the anti-lock braking pressure reduction conditions, control the fluid inlet of the brake actuator to stop fluid inlet and control its outlet to discharge brake fluid to the brake fluid reservoir. Boosting control steps: Based on the wheel speed signal, when the wheel meets the anti-lock braking boosting conditions, control the outlet of the brake actuator to stop discharging fluid, and control the high-pressure accumulator to output brake fluid to the inlet of the brake actuator.

[0016] Preferably, the system further includes a power booster pump, whose inlet is connected to the brake fluid reservoir, and whose outlet is connected in parallel with the high-pressure accumulator's inlet to one end of the pressure selection valve. The steps for controlling the high-pressure accumulator to output brake fluid include: Obtain the current pressure value of the high-voltage accumulator; When the pressure value is determined to be higher than the preset threshold, the high-pressure accumulator will output brake fluid separately and keep the power booster pump closed. When the pressure value is determined to be lower than or equal to the preset threshold, hydraulic pressure is output by the power booster pump and the high-pressure accumulator.

[0017] Preferably, the system further includes an inlet control valve and an outlet control valve, which respectively control the inlet of the brake actuator and the outlet of the brake actuator. The control method further includes: after executing the pressure reduction control step or the pressure increase control step, if it is determined from the wheel speed signal that the wheel meets the anti-lock braking pressure holding condition, the inlet control valve and the outlet control valve are both kept closed.

[0018] Preferably, the system further includes a normally open solenoid valve and a proportional regulating valve. The inlet of the normally open solenoid valve is connected to the pipeline between the proportional regulating valve and the pressure selection valve, and its outlet is connected to the brake fluid reservoir. The control method further includes: After the signal acquisition step, it is determined whether the wheel meets the anti-lock braking conditions based on the wheel speed signal. The anti-lock braking conditions include anti-lock decompression conditions, anti-lock boosting conditions, or anti-lock pressure holding conditions. If the wheel speed signal indicates that the wheel meets the anti-lock braking conditions, the normally open solenoid valve is kept closed. If the wheel speed signal indicates that the wheel does not meet the anti-lock braking conditions, the normally open solenoid valve is kept open.

[0019] In the solution implemented by the above-mentioned hydraulic anti-lock braking system and method integrating a high-voltage accumulator, the beneficial effects of the present invention include: 1. Improved system smoothness and braking responsiveness: This invention utilizes a pressure selection valve to create physical isolation, completely blocking the backflow of hydraulic fluid to the brake pedal during pressurization, fundamentally eliminating high-frequency brake pedal vibration. Simultaneously, the high-pressure accumulator provides an instant pressure source, directly releasing high-pressure brake fluid, eliminating the slow pressurization process of traditional return pumps, and enabling rapid response to pressurization commands.

[0020] 2. Optimize system costs and improve hardware utilization: This invention deeply integrates the power booster pump and high-pressure accumulator through the hydraulic booster and hydraulic adjustment module, while taking into account both conventional brake assist and anti-lock braking high-frequency pressure regulation.

[0021] 3. Optimized braking performance: By monitoring the high-voltage accumulator pressure in real time, a dynamic pressure regulation strategy can be implemented. When the pressure is sufficient, the high-voltage accumulator independently boosts the pressure; when the pressure is insufficient, the power booster pump works in conjunction with the high-voltage accumulator to supply liquid, adapting to various complex operating conditions and ensuring excellent pressure regulation performance. Attached Figure Description

[0022] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 The diagram shown is a schematic representation of the system structure in one embodiment of the present invention. Figure 2 The diagram shown is a control module diagram of an electronic control unit according to an embodiment of the present invention; Figure 3 The diagram shown is a structural diagram of a hydraulic adjustment module according to an embodiment of the present invention; The following are component designations: 1. Master cylinder; 2. Hydraulic booster; 3. Pressure relief valve; 4. Accumulator; 5. Pressure sensor; 6. Hydraulic adjustment module; 6a. Inlet control valve; 6b. Outlet control valve; 6c. Pressure selection valve; 6d. Normally open solenoid valve; 6e. Proportional regulating valve; 6f. Wheel cylinder pressure sensor; 7. Wheel cylinder; 8. Wheel speed sensor; 9. Brake pedal; 10. Power booster pump; 11. Check valve; 12. Electronic control unit; 13. Brake fluid reservoir; 14. Power booster fluid supply path. Detailed Implementation

[0024] The embodiments of the technical solution of this application will now be described in detail with reference to the accompanying drawings. These embodiments are only used to more clearly illustrate the technical solution of this application and are therefore merely examples, and should not be used to limit the scope of protection of this application.

[0025] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms “comprising” and “having”, and any variations thereof, in the specification, claims, and foregoing description of the drawings are intended to cover non-exclusive inclusion.

[0026] In the description of the embodiments of this application, technical terms such as "first" and "second" are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, "multiple" means two or more, unless otherwise explicitly defined.

[0027] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0028] In the description of the embodiments of this application, the term "and / or" is merely a description of the relationship between related objects, indicating that there can be three relationships. For example, A and / or B can represent three situations: A exists alone, A and B exist simultaneously, and B exists alone.

[0029] In the description of the embodiments of this application, the term "multiple" refers to two or more (including two), similarly, "multiple sets" refers to two or more (including two sets), and "multiple pieces" refers to two or more (including two pieces).

[0030] In the description of the embodiments of this application, the technical terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of this application and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this application.

[0031] In the description of the embodiments of this application, unless otherwise expressly specified and limited, technical terms such as "installation," "connection," "joining," and "fixing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. For those skilled in the art, the specific meaning of the above terms in the embodiments of this application can be understood according to the specific circumstances.

[0032] Unless otherwise specified, all embodiments and optional embodiments of this application can be combined to form new technical solutions.

[0033] This application provides a hydraulic anti-lock braking system and method integrating a high-voltage accumulator. The anti-lock braking system (ABS) is a safety system that plays a crucial role in vehicle emergency braking. It is based on the electronic control system's high-frequency regulation of the hydraulic pressure at the brake actuator (i.e., the hydraulic actuator installed at the wheel to receive brake hydraulic pressure and convert it into friction braking force), thereby effectively preventing the vehicle from losing steering ability or experiencing dangerous skidding due to wheel lock-up.

[0034] Traditional anti-lock braking systems (ABS) typically rely on a base brake pressure source and a hydraulic regulating module containing a return pump to achieve a high-frequency "pressure boost-pressure hold-pressure depressurization" cycle, thereby regulating wheel cylinder pressure. In this traditional architecture, the outlet of the master cylinder (directly connected to the driver's brake pedal) and the high-pressure outlet of the return pump are connected in parallel via a T-junction on the path leading to the brake actuator. However, this traditional architecture has significant flaws in the physical topology of the hydraulic lines, leading to the following problems in practical applications: Firstly, there is the issue of decompression response delay. During the decompression phase, when the wheels are about to lock up and slip due to excessive braking force, the system must immediately reduce the hydraulic pressure in the brake actuator to restore wheel traction, requiring the rapid discharge of some high-pressure brake fluid. However, traditional systems discharge this brake fluid into a very small low-pressure buffer chamber. The instantaneous influx of brake fluid causes a sharp increase in pressure within this narrow chamber, creating strong reverse resistance. This prevents the remaining brake fluid in the brake actuator from continuing to drain smoothly and rapidly, resulting in a significant response delay in the decompression action.

[0035] Secondly, there is the issue of high-frequency brake pedal vibration. During the boost phase, when the wheels regain speed and braking force needs to be re-established, and the low-pressure buffer chamber must be emptied in preparation for the next depressurization action, the system activates the electric return pump. Through extremely frequent mechanical reciprocating motion, the pump forcibly extracts the brake fluid from the low-pressure buffer chamber and pumps it into the connecting passage at high frequency. This high-frequency periodic drainage generates severe hydraulic pulsations. Because the return pump outlet shares a passage with the brake master cylinder, the severe hydraulic shock flows upwards, directly impacting the piston in the brake master cylinder. This ultimately causes the driver's brake pedal to vibrate violently and frequently, easily triggering panic and causing the driver to accidentally release the pedal.

[0036] Thirdly, its adjustment performance is limited. In extreme conditions such as long downhill slopes on icy or snowy roads or frequent switching between high and low friction coefficient surfaces, requiring continuous high-frequency triggering of anti-lock braking, the traditional return pump, being a mechanical pump, has its maximum displacement strictly limited by motor speed and plunger volume. When the brake actuator needs to continuously discharge large amounts of brake fluid to reduce pressure due to frequent lock-up, if the discharge rate exceeds the limit flow rate of the return pump to draw it back into the connection passage, the low-pressure buffer chamber will quickly become saturated with brake fluid. Once the buffer chamber is saturated, the high pressure in the brake actuator has nowhere to be released, causing the system to completely lose its pressure reduction and adjustment capabilities, and the wheels will lock up directly. Simultaneously, the flow bottleneck will also lead to slow pressure build-up in the subsequent pressurization phase, seriously threatening driving safety.

[0037] Fourth, the system has high costs and low hardware utilization. In traditional architectures, the anti-lock braking system's return pump is only activated in rare lock-up situations, remaining idle for extended periods, resulting in extremely low hardware utilization. Furthermore, new energy vehicles, lacking an engine vacuum source, must be equipped with expensive electronic vacuum pumps and vacuum tanks, leading to significant hardware redundancy and high costs.

[0038] To overcome the above-mentioned shortcomings, this invention innovatively proposes a hydraulic anti-lock braking system with an integrated accumulator. This system introduces a high-pressure accumulator 4 as an energy release element to achieve smooth pressurization, and uses a pressure selection valve 6c to physically seal the passage for high-pressure brake fluid to backflow into the brake pedal 9.

[0039] Please see Figure 1 and Figure 3 In one embodiment of the present invention, a hydraulic anti-lock braking system with an integrated accumulator is provided, including a braking actuator 7, and further including: a high-pressure accumulator 4, which stores brake fluid; a hydraulic regulating module 6, which integrates an inlet control valve 6a, an outlet control valve 6b, a pressure selection valve 6c, a normally open solenoid valve 6d, and a proportional regulating valve 6e, wherein the two inlets of the pressure selection valve 6c are respectively connected to the outlet of the main hydraulic power source and the output fluid path of the high-pressure accumulator 4, and its outlet is connected to the inlet of the braking actuator 7; and a brake fluid reservoir 13, whose outlet is connected to the inlet of the main hydraulic power source and whose inlet is connected to the outlet of the braking actuator 7.

[0040] Specifically, the brake actuator 7 can be used to convert the received hydraulic energy into friction braking force. It can be a wheel cylinder, such as a piston brake wheel cylinder. Alternatively, a caliper disc brake actuator can also be used.

[0041] The high-pressure accumulator 4 can be used to store high-pressure brake fluid and release pressure during the pressurization phase. It can be a high-pressure bladder accumulator, a piston accumulator, or a diaphragm accumulator.

[0042] The hydraulic regulating module 6 can be used to integrate control valve groups to achieve pressure regulation. The pressure selection valve 6c can be integrated into the hydraulic regulating module 6 to realize pressure comparison switching and physical isolation between the main hydraulic source and the high-pressure accumulator 4 passage. The pressure selection valve 6c can be a shuttle valve or a logic gate circuit composed of two oppositely arranged check valves.

[0043] The main hydraulic power source can be used to generate basic hydraulic pressure. It can be a powertrain consisting of a master brake cylinder 1 and a hydraulic booster 2. A booster fluid supply passage 14 can be connected between the high-pressure accumulator 4 and the hydraulic booster 2, using the hydraulic energy of the high-pressure accumulator 4 to drive the hydraulic booster 2 to collaboratively push the piston of the master brake cylinder 1.

[0044] The brake fluid reservoir 13 can be used to store brake fluid. It can be a normal pressure brake fluid reservoir.

[0045] In this embodiment, during the normal braking phase (non-anti-lock braking adjustment state), when the driver depresses the brake pedal 9, a basic hydraulic pressure is established inside the main hydraulic power source. This high-pressure brake fluid flows to the main hydraulic power source inlet of the pressure selection valve 6c, directly pushing open the internal valve core due to the pressure difference, and smoothly injecting into the inlet of the brake actuator 7, thereby converting hydraulic energy into frictional braking force at the wheels. At this time, the high-pressure accumulator 4 is not actively triggered to release, and the pressure selection valve 6c only maintains unidirectional conduction from the main hydraulic power source to the brake actuator 7, which does not affect the normal driver's brake pedal feel at all.

[0046] Furthermore, when entering the anti-lock braking decompression phase, the input of the main hydraulic power source is cut off, and the high-pressure brake fluid in the brake actuator 7 is directly discharged into the low-pressure, normal-pressure brake fluid reservoir 13 through its outlet. Since the top of the drained brake fluid reservoir 13 is usually open to the atmosphere to maintain normal atmospheric pressure, and as a centralized storage container for the vehicle's brake fluid, its internal volume is much larger than the miniature low-pressure buffer chamber inside the valve block of a traditional system. This large, normal-pressure space completely eliminates the back pressure resistance caused by the low-pressure buffer chamber of a traditional system, achieving extremely rapid decompression response.

[0047] Furthermore, when entering the anti-lock braking system (ABS) boost phase, the high-pressure accumulator 4 releases the high-pressure brake fluid stored within it. When this high-pressure brake fluid flows to the accumulator-side inlet of the pressure selector valve 6c, the pressure on that side instantaneously exceeds the pressure on the main hydraulic power source side. This causes the valve core inside the pressure selector valve 6c to be immediately pushed towards the main hydraulic power source, physically blocking the path to the main hydraulic power source. Subsequently, the high-pressure brake fluid from the high-pressure accumulator 4 is smoothly injected into the inlet of the brake actuator 7 via the pressure selector valve 6c to establish braking force. This structure utilizes the pressure release from the high-pressure accumulator 4 to replace the reciprocating impact of the traditional pump and completely cuts off the hydraulic backflow path to the brake pedal, eliminating the high-frequency vibration of the brake pedal from its physical source.

[0048] Please see Figure 1 and Figure 3 In one embodiment of the present invention, the hydraulic regulating module 6 further integrates a proportional regulating valve 6e, the outlet of which is connected to one end inlet of the pressure selection valve 6c; the system also includes a power booster pump 10, the inlet of which is connected to the brake fluid reservoir 13, and the outlet of which is connected in parallel with the liquid port of the high-pressure accumulator 4 to the inlet of the proportional regulating valve 6e. Specifically, a one-way valve 11 is also provided to prevent high-pressure backflow.

[0049] Specifically, the proportional control valve 6e can be used for proportional regulation of fluid flow. It can be a linear solenoid control valve. It changes the valve opening by inputting a varying current signal, thus achieving a linear change in output flow rate. Of course, other compatible valves can also be used.

[0050] The power booster pump 10 can be used to increase brake fluid pressure. It can be an electric booster pump or other compatible pumps.

[0051] This embodiment adds a continuous power source (power booster pump 10) and a proportional control structure (proportional control valve 6e) to the basic architecture. During normal braking, the power booster pump 10 is in a dormant state and does not work, and the proportional control valve 6e does not participate in active regulation (maintaining an initial closed state). The main hydraulic pressure established when the driver presses the brake pedal directly opens the pressure selection valve 6c and injects it into the brake actuator 7, as described above. At this time, the high-pressure brake fluid pre-stored in the high-pressure accumulator 4 is firmly locked and physically isolated by the closed proportional control valve 6e (and its associated structure), ensuring that the high-pressure energy reservoir and the normal master cylinder brake oil circuit do not interfere with each other.

[0052] During the anti-lock braking decompression phase, the brake actuator 7 continues to discharge fluid and depressurize the brake fluid reservoir 13.

[0053] During the anti-lock braking and pressure holding phase, the proportional control valve 6e is in a throttling or minimally open state, maintaining stable pressure within the brake actuator 7. At this time, the power booster pump 10 draws brake fluid discharged from the brake fluid reservoir 13 in the previous stage, pressurizes it, and pumps it out. Due to the throttling effect of the proportional control valve 6e, this portion of high-pressure brake fluid is fed into the high-pressure accumulator 4 through the one-way valve 11, converting the kinetic energy of the brake fluid into the potential energy of the accumulator for storage. The one-way valve 11 ensures that the high pressure does not flow back to the pump body.

[0054] During the anti-lock braking boosting phase, the system no longer relies solely on the high-pressure accumulator 4 to blindly release pressure. Instead, it allows the high-pressure brake fluid in the high-pressure accumulator 4 and the hydraulic pressure pumped out by the power booster pump 10 in real time to converge at the inlet of the proportional control valve 6e. The proportional control valve 6e changes its valve port cross-sectional area according to the control signal, thus controlling and distributing this powerful and forceful high-pressure fluid flow. After proportional fine-tuning, the smooth high-pressure brake fluid flows again through the pressure selection valve 6c and, under the protection of blocking the backflow path of the main hydraulic power source, is injected into the brake actuator 7 at a controlled rate. This scheme ensures continuous and stable pressure source during continuous high-frequency triggering of anti-lock braking, and that the boosting process is smooth and controllable.

[0055] Please see Figure 3 In one embodiment of the present invention, the hydraulic adjustment module 6 also integrates a normally open solenoid valve 6d.

[0056] Specifically, the normally open solenoid valve 6d can be used to maintain the physical opening of the pressure relief return path, ensuring that the pipeline pressure is at a safe level. It can be a power-off normally open direct-acting solenoid valve.

[0057] In addition, a pressure relief valve 3 can be installed to prevent pressure overload in the internal piping of the system, thereby protecting structural components from high pressure damage. It can be an electronically controlled pressure relief valve, a safety relief valve, or a proportional relief valve with overpressure protection.

[0058] In this embodiment, the inlet of the normally open solenoid valve 6d is connected to the main pipeline between the proportional regulating valve 6e and the pressure selection valve 6c, and its outlet is connected to the brake fluid reservoir 13 which is in a normal or low pressure state.

[0059] Specifically, during normal braking (non-anti-lock braking), the normally open solenoid valve 6d is de-energized, and its valve port remains fully open under the action of the internal return spring. At this time, the rear end of the proportional control valve 6e is physically connected to the brake fluid reservoir 13. When the driver normally builds pressure through the main hydraulic power source and brakes via the pressure selector valve 6c, even if there is a slight hydraulic leakage in the proportional control valve 6e, or residual thermal expansion pressure in the pipeline, this excess brake fluid will be guided back to the brake fluid reservoir 13 without obstruction through the normally open solenoid valve 6d. This ensures that the pressure on the accumulator side of the pressure selector valve 6c is always at an absolute zero pressure, and will never accidentally open the pressure selector valve 6c, causing the brake actuator 7 to brake incorrectly, perfectly guaranteeing the feel of normal braking and the absolute safety of the entire vehicle.

[0060] When the system officially enters the anti-lock boost or pressure holding stage, the electronic control unit 12 immediately supplies current to the coil of the normally open solenoid valve 6d, which seals the valve port and cuts off the return path to the brake fluid reservoir 13, thereby forming a closed and controlled high-pressure regulation environment together with other components.

[0061] During the anti-lock braking decompression phase, although pressure relief mainly relies on the fluid outlet channel of the brake actuator itself, the presence of the normally open solenoid valve 6d ensures that the regulating circuit itself can quickly release the high-pressure state at any time according to the command. For example, the extremely high-pressure brake fluid stored in the regulating circuit between the proportional regulating valve 6e and the pressure selection valve 6c can also be instantly discharged back into the brake fluid reservoir 13 by directly opening the normally open solenoid valve 6d (which will return to normally open after power is cut off). This coordination ensures that the wheels can unlock quickly and more thoroughly release the high-pressure standby state inside the entire system, preventing residual high-pressure brake fluid from accidentally rushing into the wheel cylinder and causing secondary lock-up or interference with the brake pedal feel.

[0062] In addition, a pressure relief valve 3 is installed on the high-pressure pipeline from the power booster pump 10 to the high-pressure accumulator 4. During actual system operation, if the power booster pump 10 continues to operate at full speed due to a control logic malfunction, or if a sharp increase in ambient temperature causes the sealed fluid in the pipeline to expand, when the hydraulic pressure in that local pipeline exceeds the pressure threshold of the pressure relief valve 3, the high-pressure fluid will forcefully push open the valve core of the pressure relief valve 3, automatically opening the overflow channel and guiding the overloaded high-pressure brake fluid safely back to the brake fluid reservoir 13. When the pipeline pressure drops and returns to within the safe threshold, the pressure relief valve 3 closes again. This purely physical pressure relief process provides the system with a final, robust mechanical safety barrier.

[0063] Please see Figure 1 and Figure 2 In one embodiment of the present invention, the system may further include: a wheel speed sensor 8, mounted on the wheel; an inlet control valve 6a (i.e., a pressure boosting valve) and an outlet control valve 6b (i.e., a pressure reducing valve); and an electronic control unit 12.

[0064] Specifically, the wheel speed sensor 8 can be used to dynamically acquire wheel speed data during driving or braking, enabling the system to calculate the wheel slip ratio. It can employ an active Hall effect wheel speed sensor as an alternative, a passive magnetoelectric sensor, or a higher-precision photoelectric coded sensor.

[0065] The inlet control valve 6a and outlet control valve 6b can be used to perform specific flow control and diversion actions, thereby controlling the high-pressure injection at the inlet end of the brake actuator 7 and the pressure release at the outlet end, respectively. They can be high-frequency response two-position two-way high-speed switching solenoid valves with extremely short opening and closing times; alternatively, more precise control can be achieved using a three-position three-way proportional control valve, a slide valve multi-way controller, or other suitable structures.

[0066] The electronic control unit 12 can be used to perform high-speed acquisition, filtering, and noise reduction of electrical signals from various sensors, execute complex anti-lock braking logic control algorithms, and ultimately output high-power current drive commands to each actuator valve group and pump body. It can be a standalone microcontroller unit (ECU). Alternatively, its control algorithm can be directly integrated as a separate software module into the vehicle's advanced domain controller.

[0067] In this embodiment, the electronic control unit 12 can be electrically connected to the wheel speed sensor 8, the power booster pump 10, the proportional control valve 6e, the normally open solenoid valve 6d, the inlet control valve 6a, and the outlet control valve 6b, respectively. During normal braking, the driver depresses the brake pedal. At this time, the electronic control unit 12 and its subordinate wheel speed sensor 8 are activated for real-time monitoring. The electronic control unit 12 comprehensively analyzes the speed signals of each wheel and calculates that the current wheel slip ratio is within the safe adhesion range (not meeting the anti-lock braking conditions). Therefore, the electronic control unit 12 controls the inlet control valve 6a to remain normally open and controls the outlet control valve 6b to remain normally closed. The high-pressure brake fluid generated by the main hydraulic power source pushes open the pressure selection valve 6c and passes through the inlet control valve 6a to enter the brake actuator 7, realizing the correspondence between the braking force and the driver's pedal depressing depth.

[0068] Once the electronic control unit 12 predicts that the slip ratio of a wheel is about to exceed the optimal adhesion coefficient range (i.e., meet the anti-lock braking conditions), the electronic control unit 12 can drive the inlet control valve 6a to cut off the high-pressure fluid from upstream (main hydraulic power source or high-pressure accumulator 4). At the same time, it can coordinately control the outlet control valve 6b to open the drain and pressure relief passage to the brake fluid reservoir 13, and the braking force at the wheel will be reduced rapidly.

[0069] During the anti-lock pressure holding phase, the electronic control unit 12 controls the liquid outlet control valve 6b to close, while keeping the liquid inlet control valve 6a in the closed state, locking the hydraulic pressure inside the brake actuator 7 and maintaining the current slip ratio.

[0070] During the anti-lock braking and boosting phase, the electronic control unit 12 controls the normally open solenoid valve 6d to close and establish a high-pressure environment, and controls the proportional regulating valve 6e to open at a specific angle to release the high pressure from the accumulator; finally, it controls the outlet control valve 6b to remain closed and opens the inlet control valve 6a. High-pressure brake fluid passes through the inlet control valve 6a and is injected into the brake actuator 7.

[0071] Please see Figure 1 and Figure 2 In one embodiment of the present invention, the system further includes: an accumulator pressure sensor 5 and a wheel cylinder pressure sensor 6f.

[0072] The accumulator pressure sensor 5 can be used to convert the high-voltage physical signal inside the high-voltage accumulator 4 into a voltage or current electrical signal, so that the system can monitor the pressure status of the high-voltage accumulator 4 at all times. It can be a thin-film piezoresistive pressure sensor. As an alternative structure, a ceramic capacitive pressure sensor or other compatible sensors can also be used.

[0073] The wheel cylinder pressure sensor 6f can be used to monitor the internal hydraulic pressure of the brake actuator 7 in real time and convert it into an electrical signal, providing the most crucial feedback basis for the system's pressure closed-loop follow-up control. It can be a piezoresistive pressure sensor; as an alternative, a capacitive (MEMS) sensor can also be used.

[0074] In this embodiment, the accumulator pressure sensor 5 is installed on the main pipeline directly communicating with the high-pressure chamber inside the high-pressure accumulator 4, and is electrically connected to the signal input terminal of the electronic control unit 12. The wheel cylinder pressure sensor 6f is installed on the fluid inlet passage of the brake actuator 7, and is also electrically connected to the electronic control unit 12.

[0075] Specifically, the accumulator pressure sensor 5 continuously reports the pressure status of the high-pressure accumulator 4. If the pressure is sufficient, the system is in standby mode. If the accumulator pressure drops slightly due to the vehicle being parked for a long time, the electronic control unit 12 will start the power booster pump 10 to pre-charge it without interfering with normal braking operations. At the same time, the wheel cylinder pressure sensor 6f senses and records the actual wheel cylinder pressure change curve caused by the driver pressing the brake pedal in real time.

[0076] During the anti-lock decompression phase, the electronic control unit 12 can set a target decompression slope. It reads the rate of pressure drop in real time through the wheel cylinder pressure sensor 6f. If the pressure drops too quickly, it finely adjusts and shortens the opening duty cycle of the liquid outlet control valve 6b to prevent excessive pressure loss.

[0077] During the anti-lock pressure holding phase, even though both the inlet control valve 6a and the outlet control valve 6b are closed, if there is a micro-deformation in the pipeline or a sudden change in ambient temperature causing a slight pressure drop, the wheel cylinder pressure sensor 6f will immediately detect this change. The electronic control unit 12 will then instruct the execution of a slight compensation action to regulate the pressure by opening and closing the valves in the control system.

[0078] During the anti-lock braking boosting phase, the high-pressure accumulator 4 releases hydraulic pressure, causing its own pressure to decrease due to consumption. When the accumulator pressure sensor 5 detects that it is below the lower threshold, the system immediately activates the power booster pump 10 at high power to replenish the energy, ensuring that the high-pressure accumulator 4 has sufficient pressure energy to respond to anti-lock braking adjustments at any time. At the same time, as this pressure energy is injected into the brake actuator 7 through the proportional control valve 6e and the pressure selection valve 6c, the electronic control unit 12 uses real-time data transmitted from the wheel cylinder pressure sensor 6f to perform high-frequency calculations with the ideal boosting curve. Once a spike or overshoot is detected in the pressure rise curve, the electronic control unit 12 immediately dynamically fine-tunes the proportional control valve 6e to change its cross-sectional area, or adjusts the opening and closing frequency of the inlet control valve 6a. This closed-loop physical cycle of real-time sensing and real-time correction smooths out pressure fluctuations, making the boosting and depressurization processes smoother.

[0079] In one embodiment of the present invention, a control method for a hydraulic anti-lock braking system with an integrated accumulator is also provided, which can be applied to the aforementioned hydraulic anti-lock braking system. The control method includes: a signal acquisition step, acquiring wheel speed signals; a decompression control step, controlling the inlet end of the brake actuator to stop inleting brake fluid and controlling its outlet end to discharge brake fluid to the brake fluid reservoir when the wheel speed signal determines that the wheel meets the anti-lock decompression conditions; and a pressure boosting control step, controlling the outlet end of the brake actuator to stop outleting brake fluid and controlling the accumulator to output brake fluid to the inlet end of the brake actuator when the wheel speed signal determines that the wheel meets the anti-lock pressure boosting conditions.

[0080] Specifically, during the signal acquisition phase, the electronic control unit 12 collects the pulse signals from the wheel speed sensors 8 at each wheel in real time and calculates the current wheel slip ratio. During the pressure reduction control phase, the electronic control unit 12 instructs the inlet control valve 6a to close and simultaneously opens the outlet control valve 6b. Since the brake fluid reservoir 13 is in a low-pressure normal pressure state, the high-pressure fluid in the brake actuator 7 is rapidly released into the brake fluid reservoir 13. During the pressure boosting control phase, the electronic control unit 12 instructs the outlet control valve 6b to close, and then guides the high-pressure accumulator 4 to release the pre-stored brake fluid, which is then reinjected into the brake actuator 7 via the pressure selection valve 6c.

[0081] In another alternative embodiment, during depressurization, the high-pressure passage from the master cylinder 1 is cut off by the inlet control valve 6a. During pressurization, the output pressure of the high-pressure accumulator 4 acts on one end of the pressure selection valve 6c, forcing the valve to automatically close the lateral passage to the master cylinder 1, thereby physically isolating the transmission of hydraulic fluctuations to the brake pedal 9 and solving the problem of high-frequency pedal vibration.

[0082] In one embodiment of the present invention, the control method further includes: acquiring the current pressure value of the accumulator; determining that when the pressure value is higher than a preset threshold, the accumulator outputs brake fluid alone while keeping the power booster pump closed; determining that when the pressure value is lower than or equal to the preset threshold, the power booster pump and the accumulator jointly output hydraulic pressure; and controlling the inlet control valve and the outlet control valve to remain closed when the anti-lock pressure holding condition is met.

[0083] In practice, the electronic control unit 12 monitors the accumulator pressure sensor 5 in real time. If the pressure in the high-pressure accumulator 4 is sufficient (above the preset threshold), the high-pressure accumulator 4 is used first to achieve rapid pressurization, and the power booster pump 10 is in a dormant state to reduce power consumption and wear. If the pressure is insufficient (below or equal to the preset threshold), the power booster pump 10 is activated for joint output. In this joint output mode, the hydraulic pressure pumped by the power booster pump 10 can be directly combined with the remaining hydraulic pressure in the high-pressure accumulator 4 for output.

[0084] Alternatively, as a smoother control strategy, the power booster pump 10 first rapidly charges and pressurizes the high-pressure accumulator 4 through the one-way valve 11, and then the high-pressure accumulator 4 uniformly outputs high-pressure brake fluid to the downstream pipeline.

[0085] During the pressure holding phase, the electronic control unit 12 simultaneously places the inlet control valve 6a and the outlet control valve 6b in the cut-off position. At this time, the brake actuator 7 forms a closed hydraulic system with constant braking force.

[0086] In another optional embodiment, the above-mentioned pressurization, depressurization, and pressure holding processes all incorporate feedback from the wheel cylinder pressure sensor 6f. The electronic control unit 12 uses the real-time value obtained by the wheel cylinder pressure sensor 6f to perform a high-speed comparison with the target pressure. If the pressure rises too quickly during the pressurization phase, the valve opening or duty cycle of the proportional regulating valve 6e is finely adjusted to prevent the brake from locking up again due to pressure overshoot. At the same time, the liquid discharged from the power booster pump 10 enters the high-pressure accumulator 4 through the one-way valve 11, ensuring that the energy replenishment path is unidirectionally controlled.

[0087] In one embodiment of the present invention, the control method further includes: after the signal acquisition step, determining whether the wheel meets the anti-lock braking conditions (including depressurization, pressurization or pressure holding conditions) based on the wheel speed signal; if it meets the conditions, controlling the normally open solenoid valve to remain closed; if it does not meet the conditions, controlling the normally open solenoid valve to remain open.

[0088] Specifically, the normally open solenoid valve 6d serves as a switching switch for the system's operating state. During normal driving braking, the normally open solenoid valve 6d remains in the normally open position to ensure zero pressure at the proportional control valve 6e and prevent accidental pressure increase. Once the electronic control unit 12 detects a tendency for the wheels to lock up and enters the anti-lock braking mode, it first controls the normally open solenoid valve 6d to close, physically isolating the regulating circuit from the low-pressure brake fluid reservoir 13 and establishing a high-pressure regulating environment controlled by the proportional control valve 6e.

[0089] In one embodiment, the control method may also include additional auxiliary and protection steps to coordinate the operation of other cooperating structures within the system: during or after the pressure boosting control step, an overpressure protection step may also be included: when the hydraulic pressure of a local pipeline rises abnormally and exceeds the preset threshold of the pressure relief valve 3, the excess high-pressure brake fluid is released to the brake fluid reservoir 13 by opening the pressure relief valve 3 to prevent pressure overload and protect pipeline safety.

[0090] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and not to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application, and they should all be covered within the scope of the claims and specification of this application. In particular, as long as there is no structural conflict, the various technical features mentioned in the embodiments can be combined in any way. This application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A hydraulic anti-lock braking system integrating a high-voltage accumulator, comprising a braking actuator, characterized in that, Also includes: The system includes a high-pressure accumulator, a main hydraulic power source, and a pressure selection valve. The two inlets of the pressure selection valve are connected to the outlet of the main hydraulic power source and the output fluid path of the high-pressure accumulator, respectively, and its outlet is connected to the inlet of the brake actuator. The brake fluid reservoir has its outlet connected to the inlet of the main hydraulic power source and its inlet connected to the outlet of the brake actuator.

2. The hydraulic anti-lock braking system according to claim 1, characterized in that, Also includes: A proportional regulating valve, the outlet of which is connected to one inlet of the pressure selection valve; A power booster pump has its inlet end connected to the brake fluid reservoir, and its outlet end connected in parallel with the liquid port of the high-pressure accumulator to the inlet end of the proportional regulating valve.

3. The hydraulic anti-lock braking system according to claim 2, characterized in that, It also includes a normally open solenoid valve, whose inlet end is connected to the pipeline between the proportional regulating valve and the pressure selection valve, and whose outlet end is connected to the brake fluid reservoir.

4. The hydraulic anti-lock braking system according to claim 3, characterized in that, Also includes: Wheel speed sensor, which is installed on the wheel; The inlet control valve and the outlet control valve control the inlet and outlet of the brake actuator, respectively. The electronic control unit is electrically connected to the wheel speed sensor, the power booster pump, the proportional control valve, the normally open solenoid valve, the inlet control valve, and the outlet control valve, respectively.

5. The hydraulic anti-lock braking system according to claim 4, characterized in that, It also includes an accumulator pressure sensor, which is installed in a pipeline connected to the internal hydraulic pressure of the high-pressure accumulator, and the electronic control unit is electrically connected to the accumulator pressure sensor.

6. The hydraulic anti-lock braking system according to claim 4, characterized in that, It also includes a wheel cylinder pressure sensor, which is installed in the fluid inlet passage of the brake actuator, and the electronic control unit is electrically connected to the wheel cylinder pressure sensor.

7. A control method for a hydraulic anti-lock braking system integrating a high-voltage accumulator, applied to the hydraulic anti-lock braking system as described in any one of claims 1 to 6, characterized in that, The control method includes the following steps: Signal acquisition steps: Acquire the wheel speed signal of the wheel; Pressure reduction control steps: When the wheel speed signal determines that the wheel meets the anti-lock braking pressure reduction conditions, control the fluid inlet of the brake actuator to stop fluid inlet and control its outlet to discharge brake fluid into the brake fluid reservoir. Boosting control steps: When the wheel speed signal determines that the wheel meets the anti-lock braking boosting conditions, control the outlet of the brake actuator to stop discharging fluid, and control the high-pressure accumulator to output brake fluid to the inlet of the brake actuator.

8. The control method according to claim 7, characterized in that, The system also includes a power booster pump, whose inlet is connected to the brake fluid reservoir, and whose outlet is connected in parallel with the liquid port of the high-pressure accumulator to one inlet of the pressure selection valve. The step of controlling the output of brake fluid from the high-pressure accumulator includes: Obtain the current pressure value of the high-voltage accumulator; When the pressure value is determined to be higher than a preset threshold, the high-pressure accumulator outputs brake fluid separately, while keeping the power booster pump off; When the pressure value is determined to be lower than or equal to the preset threshold, hydraulic pressure is output jointly by the power booster pump and the high-pressure accumulator.

9. The control method according to claim 7, characterized in that, The system further includes an inlet control valve and an outlet control valve, which respectively control the inlet and outlet of the brake actuator. The control method further includes: after executing the pressure reduction control step or the pressure increase control step, if it is determined based on the wheel speed signal that the wheel meets the anti-lock braking pressure holding conditions, the inlet control valve and the outlet control valve are both kept closed.

10. The control method according to claim 9, characterized in that, The system further includes a normally open solenoid valve and a proportional regulating valve. The inlet of the normally open solenoid valve is connected to the pipeline between the proportional regulating valve and the pressure selection valve, and its outlet is connected to the brake fluid reservoir. The control method further includes: After the signal acquisition step, it is determined whether the wheel meets the anti-lock braking conditions based on the wheel speed signal, wherein the anti-lock braking conditions include the anti-lock decompression condition, the anti-lock boosting condition, or the anti-lock pressure holding condition. If the wheel speed signal indicates that the wheel meets the anti-lock braking conditions, the normally open solenoid valve is controlled to remain closed. If it is determined based on the wheel speed signal that the wheel does not meet the anti-lock braking conditions, the normally open solenoid valve is controlled to remain open.

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