Vehicle braking system and vehicle braking method

Abstract

To provide a vehicle braking system including a DPB module and an ESP module.SOLUTION: A DPB module includes a brake master cylinder, a master cylinder reservoir, and a hydraulic cylinder. An ESP module includes a remote reservoir and provides each pair of brake wheel cylinders with a liquid supply line, a liquid discharge line, and a compensating liquid supply line used to communicate with the liquid supply line and the liquid discharge line. The liquid supply line selectively communicates with a high-pressure side of the brake master cylinder or a high-pressure side of the hydraulic cylinder. The liquid discharge line allows brake fluid in each brake wheel cylinder to be discharged to the remote reservoir. The compensating liquid supply line includes a pump, thereby, the pressurized brake fluid drawn from the liquid discharge line can be supplied to the liquid supply line.SELECTED DRAWING: Figure 1a

Description

[Technical field]

[0001] FIELD OF THE DISCLOSURE This application relates to vehicle braking systems and methods of vehicle braking implemented using vehicle braking systems. [Background technology]

[0002] At present, a two-box type separated vehicle braking system generally includes a separated power brake (DPB) module and an electronic stability program (ESP) module. The DPB module includes a master cylinder reservoir with a geometric structure that changes according to customer requirements, and the master cylinder reservoir is used to provide brake fluid to the brake master cylinder and the ESP module. Since the geometric structure of the master cylinder reservoir changes according to the available mounting space on the vehicle and customer requirements, in most cases, its capacity, size, internal structure, interface parameters, etc. change, thereby significantly increasing the associated design, validation, manufacturing, packaging and transportation costs and reducing versatility. The DPB module including the master cylinder reservoir is typically mounted on the firewall of the vehicle where space is limited, and it is very difficult to perform installation and repair at the aforementioned location.

[0003] The DPB module further includes a hydraulic cylinder including a low pressure chamber and a high pressure chamber. The pressurized brake fluid discharged from the high pressure chamber of the hydraulic cylinder is supplied to the brake wheel cylinder of the vehicle. Meanwhile, the brake fluid discharged from the brake wheel cylinder needs to be pressurized by the pump of the ESP module before returning to the high pressure chamber of the hydraulic cylinder. The operation of the pump and the electric machine driving the pump as well as the return of the high pressure brake fluid lead to pressure fluctuations on the hydraulic cylinder. This is disadvantageous for the hydraulic cylinder. The DPB module including the aforementioned hydraulic cylinder is typically mounted in the form of a cantilever on the vehicle's firewall having limited stiffness and is mechanically connected to the brake pedal. The vibrations are easily transmitted to the driver's foot, thereby impairing the driver's driving experience.

[0004] When the ESP module of the vehicle braking system is in continuous active pressurization operation at low temperature, the rubber sealing ring will become stiff, and air will inevitably be drawn into the braking system, which will change the characteristics of the pressure-compression volume (PV) curve of the vehicle braking system and make the brake pedal feel soft.

[0005] The master cylinder reservoir and the ESP module are connected to each other by a one-way liquid intake valve. The ESP module absorbs the brake fluid in the master cylinder reservoir by means of the one-way liquid intake valve using the negative pressure generated by the pump. In this way, the ESP module can supply brake fluid to the brake wheel cylinders instead of the hydraulic cylinder when the brake fluid in the high pressure chamber of the hydraulic cylinder is about to run out. However, the efficiency of the active pressure increase process of the brake wheel cylinders in the aforementioned operating mode is low, since it is necessary to overcome the preload applied by the spring of the one-way liquid intake valve and the flow resistance of the long connecting line between the master cylinder reservoir and the ESP module.

[0006] Additionally, to ensure fluid absorption efficiency during active pressure buildup in the ESP module, the ESP module is typically located lower than the master cylinder reservoir, thereby increasing corrosion and impact to the ESP module caused by road salt, water, dirt, etc. Summary of the Invention [Problem to be solved by the invention]

[0007] The objective of the present application is to solve one or more of the above technical problems. [Means for solving the problem]

[0008] For this purpose, the present application provides a novel vehicle braking system, comprising: a DPB module associated with a brake pedal of the vehicle; and an ESP module associated with brake wheel cylinders of the vehicle, the DPB module comprising a brake master cylinder actuated by the brake pedal, a master cylinder reservoir in fluid communication with the brake master cylinder and having a fixed volume, a pedal feel simulator, and a hydraulic cylinder driven by an electric machine, the pedal feel simulator providing a simulated circuit from the high pressure side of the brake master cylinder to the master cylinder reservoir, the ESP module comprising a remote reservoir, a liquid supply line for supplying brake fluid to each pair of brake wheel cylinders of two pairs of brake wheel cylinders of the vehicle, a liquid discharge line for draining brake fluid, and a compensation liquid supply line communicating with the liquid supply line and the liquid discharge line, The liquid supply line can be selectively in communication with the high pressure side of the brake master cylinder or the high pressure side of the hydraulic cylinder to receive and provide pressurized brake fluid to the brake wheel cylinders, the liquid discharge line is configured to allow brake fluid in each of the brake wheel cylinders to be discharged to a remote reservoir, and the compensation liquid supply line includes a pump, each of the pumps having an inlet side and an outlet side in fluid communication with the liquid discharge line and the liquid supply line, respectively, to draw from the liquid discharge line and provide pressurized brake fluid to the liquid supply line.

[0009] In one embodiment, the outlet side of the brake master cylinder is connected to the fluid supply line by an operable master cylinder shutoff valve, and the high pressure side of the hydraulic cylinder is connected to the fluid supply line by an operable hydraulic cylinder shutoff valve.

[0010] In one embodiment, the DPB module further comprises a hydraulic cylinder fluid inlet line for enabling the inlet of the hydraulic cylinder to be in fluid communication with the master cylinder reservoir.

[0011] In one embodiment, the DPB module further includes a hydraulic cylinder compensation line having one end in fluid communication with the hydraulic cylinder proximate an outlet of the hydraulic cylinder and an other end in fluid communication with a master cylinder reservoir; The hydraulic cylinder compensation line is provided with a one-way compensation valve for one-way communication from the master cylinder reservoir to the hydraulic cylinder, or an operable hydraulic cylinder compensation valve disposed between the master cylinder reservoir and the hydraulic cylinder.

[0012] In one embodiment, the remote reservoir is in fluid communication with the inlet side of the system pressure control valve on the liquid supply line by a one-way compensation valve.

[0013] In one embodiment, the vehicle braking system has one or more of the following features:

[0014] The remote reservoir is higher than the master cylinder reservoir, the remote reservoir has an oil injection port, and the master cylinder reservoir does not have an oil injection port, or the remote reservoir is lower than the master cylinder reservoir, the remote reservoir does not have an oil injection port, and the master cylinder reservoir has an oil injection port; The capacity of the remote reservoir of the ESP module is greater than the capacity of the master cylinder reservoir of the DPB module, and the remote reservoir and the master cylinder reservoir may or may not be in fluid communication with each other by a pipeline.

[0015] In one embodiment, the remote reservoir comprises first and second partially isolated remote storage spaces respectively connected to the fluid discharge lines of a first and second pair of brake wheel cylinders of the vehicle, and a third remote storage space isolated from the first and second remote storage spaces by a preset height, the third remote storage space being in fluid communication with the master cylinder reservoir of the DPB module.

[0016] In one embodiment, the ESP module includes a single fluid drain line for all of the brake wheel cylinders, the single fluid drain line being in fluid communication with a third remote storage space.

[0017] The present application further relates to a vehicle braking method performed by utilizing the vehicle braking system described above, the method including the steps of performing a braking operation by a master cylinder fluid supply braking mode, or a hydraulic cylinder fluid supply braking mode, or an ESP fluid supply braking mode, a master cylinder fluid supply brake mode including supplying pressurized brake fluid in a brake master cylinder in the DPB module to a fluid supply line of each pair of brake wheel cylinders and then to the brake wheel cylinders, and draining the brake fluid in the brake wheel cylinders to a remote reservoir; a hydraulic cylinder fluid supply braking mode including supplying pressurized brake fluid in the hydraulic cylinders in the DPB module to a fluid supply line of each pair of brake wheel cylinders and then to the brake wheel cylinders, and draining the brake fluid in the brake wheel cylinders to a remote reservoir; The ESP fluid supply mode includes allowing brake fluid in the remote reservoir to pass through the compensation fluid supply line, be pressurized by a pump on the compensation fluid supply line, and then supplied to the fluid supply line and then to the brake wheel cylinders, and draining the brake fluid in the brake wheel cylinders to the remote reservoir.

[0018] In one embodiment, the master cylinder fluid supply braking mode is executed when the brake pedal is depressed when the vehicle is not started, or when an electric machine or a hydraulic cylinder or a control unit in the DPB module fails, and an electric machine or a pump or a control unit in the ESP module fails; The hydraulic cylinder fluid supply brake mode is executed when the brake system is not faulty after the vehicle is started, The ESP fluid supply braking mode may be implemented when there is insufficient brake fluid or brake pressure in the hydraulic cylinders of the DPB module or when the DPB module has failed.

[0019] In one embodiment, a method for braking a vehicle comprises the following steps: adding fluid to the brake master cylinder by a master cylinder reservoir when the automatic vehicle holding function is performed; adding fluid to the hydraulic cylinder by a master cylinder reservoir or a remote reservoir when an automatic vehicle hold function is performed or when brake fluid in the hydraulic cylinder is depleted; and an air draining step for enabling the brake fluid in the fluid supply lines of each pair of brake wheel cylinders and the brake fluid in each brake wheel cylinder to be drained by a fluid drain line to a remote reservoir when the vehicle hold function is terminated. The present invention further includes one or more of the following:

[0020] In one embodiment, the method of vehicle braking further includes the act of gradually releasing pressure in the brake wheel cylinders when the brake pedal is gradually released when the vehicle is started.

[0021] The present application further relates to a control unit for a vehicle braking system as described above, the control unit being configured to execute the vehicle braking method as described above.A vehicle braking system may comprise a control unit as described above.

[0022] Unlike the prior art where only a single integrated master cylinder reservoir is provided, the DPB module and the ESP module of the vehicle braking system of the present application each have one brake fluid reservoir. The DPB module of the vehicle braking system of the present application has a master cylinder reservoir with a fixed geometric structure and small capacity, and the ESP module has a remote reservoir with serializable design and flexible mounting position. The master cylinder reservoir and the remote reservoir are connected by hydraulic lines to allow brake fluid to circulate. Such a configuration meets both the capacity requirements of various customers and the need to reduce the weight of the DPB module and the mounting space in the vehicle firewall as much as possible. The remote reservoir of the ESP module may be mounted higher than the master cylinder reservoir of the DPB module in the vehicle (in this case, the remote reservoir has an oil injection port, but the master cylinder reservoir does not have an oil injection port), so that the brake fluid in the remote reservoir can automatically return to the master cylinder reservoir under the action of gravity, thereby not only reducing the risk of muddy water intrusion and corrosion into the remote reservoir, but also always ensuring the amount of brake fluid in the master cylinder reservoir. Also, in the above vehicle braking system, since the suction side of the pump of the ESP module is connected to the remote reservoir at atmospheric pressure, the sucked brake fluid is no longer in a high-pressure state, so in one aspect, components such as a high-pressure switching valve and a one-way liquid suction valve are not required, reducing costs, and in another aspect, the path through which the remote reservoir supplies brake fluid to the brake wheel cylinders by the pump is significantly shortened, improving braking efficiency. In the above vehicle braking system, the brake fluid discharged from the brake wheel cylinder is discharged to a remote reservoir at atmospheric pressure via a liquid discharge line, which in one aspect eliminates the need for components such as a low-pressure accumulator, thereby reducing costs, and in another aspect eliminates pressure fluctuations in a hydraulic cylinder mounted near the vehicle's brake pedal due to the discharge of brake fluid, thereby improving the driver's driving experience.

[0023] Alternatively, the remote reservoir of the ESP module may be mounted lower than the master cylinder reservoir of the DPB module in the vehicle, and the brake fluid in the remote reservoir may be returned to the master cylinder reservoir by the higher than atmospheric pressure of the brake fluid exhausted from the brake wheel cylinders (in this case the remote reservoir does not have an oil fill port, but the master cylinder reservoir does).

[0024] The foregoing and other features and advantages of the present application will be readily understood from the following detailed description taken in conjunction with the accompanying drawings. [Brief description of the drawings]

[0025] [Figure 1a] FIG. 2 is a hydraulic circuit diagram of a vehicle braking system according to the first and second exemplary configurations of the present application. [Figure 1b] FIG. 2 is a hydraulic circuit diagram of a vehicle braking system according to the first and second exemplary configurations of the present application. [Diagram 2] FIG. 1b is a schematic diagram of the vehicle braking system of FIG. 1a utilized to perform braking in a master cylinder fluid applied braking mode; [Diagram 3] 1b are schematic diagrams of pressurizing, maintaining and depressurizing operations of the brake wheel cylinders when performing braking in a hydraulic cylinder fluid supply braking mode during normal vehicle running using the vehicle braking system of FIG. 1a, respectively. [Figure 4] 1b are schematic diagrams of pressurizing, maintaining and depressurizing operations of the brake wheel cylinders when performing braking in a hydraulic cylinder fluid supply braking mode during normal vehicle running using the vehicle braking system of FIG. 1a, respectively. [Diagram 5] 1b are schematic diagrams of pressurizing, maintaining and depressurizing operations of the brake wheel cylinders when performing braking in a hydraulic cylinder fluid supply braking mode during normal vehicle running using the vehicle braking system of FIG. 1a, respectively. [Figure 6]This is a scenario in which the vehicle braking system of FIG. 1a is utilized to perform fluid supply compensation by a remote reservoir in ESP fluid supply braking mode when brake fluid in the hydraulic cylinder is insufficient in the pressure reducing operation of FIG. 5 . [Figure 7] 1A is a scenario in which the vehicle braking system of FIG. 1A is utilized to perform fluid supply compensation by a remote reservoir in ESP fluid supply braking mode when there is insufficient brake pressure in the hydraulic cylinder in the pressurizing operation of FIG. 3. [Figure 8a] A scenario in which the vehicle braking system of FIG. 1a can be utilized to gradually release pressure in the brake wheel cylinders in a controlled manner. [Figure 8b] A scenario in which the vehicle braking system of FIG. 1a can be utilized to gradually release pressure in the brake wheel cylinders in a controlled manner. [Figure 8c] A scenario in which the vehicle braking system of FIG. 1a can be utilized to gradually release pressure in the brake wheel cylinders in a controlled manner. [Figure 8d] A scenario in which the vehicle braking system of FIG. 1a can be utilized to gradually release pressure in the brake wheel cylinders in a controlled manner. [Figure 9] 1 is a scenario in which the vehicle braking system of FIG. 1 a is utilized to perform automatic air bleeding by a remote reservoir when the automatic vehicle hold function is terminated. [Figure 10] FIG. 1b is a hydraulic circuit diagram utilizing the vehicle braking system of FIG. 1a to perform a pressurizing operation in a first redundant braking mode. [Figure 11] FIG. 1b is a hydraulic circuit diagram utilizing the vehicle braking system of FIG. 1a to perform pressurization operations in a second redundant braking mode. [Figure 12a] FIG. 11 is a hydraulic circuit diagram of a vehicle braking system according to a third and fourth exemplary configuration of the present application. [Figure 12b] FIG. 11 is a hydraulic circuit diagram of a vehicle braking system according to a third and fourth exemplary configuration of the present application. [Figure 13]FIG. 12b is a schematic diagram of the vehicle braking system of FIG. 12a utilized to perform braking in a master cylinder fluid applied braking mode. [Figure 14] 12b are schematic diagrams of pressurizing, maintaining and depressurizing operations of the brake wheel cylinders when the vehicle braking system of FIG. 12a is utilized to perform braking in a hydraulic cylinder fluid supply braking mode during normal vehicle running. [Figure 15] 12b are schematic diagrams of pressurizing, maintaining and depressurizing operations of the brake wheel cylinders when the vehicle braking system of FIG. 12a is utilized to perform braking in a hydraulic cylinder fluid supply braking mode during normal vehicle running. [Figure 16] 12b are schematic diagrams of pressurizing, maintaining and depressurizing operations of the brake wheel cylinders when the vehicle braking system of FIG. 12a is utilized to perform braking in a hydraulic cylinder fluid supply braking mode during normal vehicle running. [Figure 17] 16 is a scenario in which the vehicle braking system of FIG. 12a is utilized to perform fluid supply compensation by a remote reservoir in ESP fluid supply braking mode when brake fluid in the hydraulic cylinder is insufficient in the pressure reducing operation of FIG. [Figure 18] 12a is utilized to perform fluid supply compensation by a remote reservoir in ESP fluid supply braking mode when there is insufficient brake pressure in the hydraulic cylinder in the pressurizing operation of FIG. 14. [Figure 19a] A scenario in which the vehicle braking system of FIG. 12a can be utilized to gradually release pressure in the brake wheel cylinders in a controlled manner. [Figure 19b] A scenario in which the vehicle braking system of FIG. 12a can be utilized to gradually release pressure in the brake wheel cylinders in a controlled manner. [Figure 19c] A scenario in which the vehicle braking system of FIG. 12a can be utilized to gradually release pressure in the brake wheel cylinders in a controlled manner. [Figure 19d]A scenario in which the vehicle braking system of FIG. 12a can be utilized to gradually release pressure in the brake wheel cylinders in a controlled manner. [Figure 20] 12a is a scenario in which the vehicle braking system of FIG. 12a is utilized to perform automatic air bleeding by a remote reservoir when the automatic vehicle hold function is terminated. [Figure 21] FIG. 12b is a hydraulic circuit diagram utilizing the vehicle braking system of FIG. 12a to perform a pressurizing operation in a first redundant braking mode. [Figure 22] FIG. 12b is a hydraulic circuit diagram utilizing the vehicle braking system of FIG. 12a to perform pressurization operations in a second redundant braking mode. [Figure 23a] FIG. 11 is a hydraulic circuit diagram of a vehicle braking system according to the fifth and sixth exemplary configurations of the present application. [Figure 23b] FIG. 11 is a hydraulic circuit diagram of a vehicle braking system according to the fifth and sixth exemplary configurations of the present application. [Figure 24] FIG. 23b is a schematic diagram of the vehicle braking system of FIG. 23a utilized to perform braking in a master cylinder fluid applied braking mode. [Diagram 25] 23b are schematic diagrams of pressurization, pressure maintenance and depressurization operations of the brake wheel cylinders when the vehicle braking system of FIG. 23a is utilized to perform braking in a hydraulic cylinder fluid supply braking mode during normal vehicle running. [Figure 26] 23b are schematic diagrams of pressurization, pressure maintenance and depressurization operations of the brake wheel cylinders when the vehicle braking system of FIG. 23a is utilized to perform braking in a hydraulic cylinder fluid supply braking mode during normal vehicle running. [Figure 27] 23b are schematic diagrams of pressurization, pressure maintenance and depressurization operations of the brake wheel cylinders when the vehicle braking system of FIG. 23a is utilized to perform braking in a hydraulic cylinder fluid supply braking mode during normal vehicle running. [Figure 28]27. This is a scenario in which the vehicle braking system of FIG. 23a is utilized to provide remote reservoir fluid supply compensation in ESP fluid supply braking mode when brake fluid in the hydraulic cylinder is insufficient during the pressure reducing operation of FIG. 27. [Figure 29] 25 is a scenario in which the vehicle braking system of FIG. 23a is utilized to perform fluid supply compensation by a remote reservoir in ESP fluid supply braking mode when there is insufficient brake pressure in the hydraulic cylinder in the pressurizing operation of FIG. 25. [Figure 30a] A scenario in which the vehicle braking system of FIG. 23a can be utilized to gradually release pressure in the brake wheel cylinders in a controlled manner. [Figure 30b] A scenario in which the vehicle braking system of FIG. 23a can be utilized to gradually release pressure in the brake wheel cylinders in a controlled manner. [Figure 30c] A scenario in which the vehicle braking system of FIG. 23a can be utilized to gradually release pressure in the brake wheel cylinders in a controlled manner. [Figure 30d] A scenario in which the vehicle braking system of FIG. 23a can be utilized to gradually release pressure in the brake wheel cylinders in a controlled manner. [Diagram 31] 23a is utilized to perform an automatic air bleed by a remote reservoir when the automatic vehicle hold function is terminated. [Diagram 32] FIG. 23b is a hydraulic circuit diagram utilizing the vehicle braking system of FIG. 23a to perform a pressurizing operation in a first redundant braking mode. [Diagram 33] FIG. 23b is a hydraulic circuit diagram utilizing the vehicle braking system of FIG. 23a to perform pressurizing operation in a second redundant braking mode. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0026] Six exemplary configurations of the split vehicle braking system of the present application are described in detail below with reference to the accompanying drawings. Figures 1a, 1b, 12a, 12b, 23a and 23b show the first to sixth exemplary configurations, respectively. The braking system generally includes a split powered brake (DPB) module 100 and an electronic stability program (ESP) module 200, as shown. The first exemplary configuration of the present invention will be described first with reference to Figures 1a and 2 to 11.

[0027] Referring to FIG. 1a, the DPB module 100 of the braking system first includes a brake master cylinder MC that is braked by a brake pedal B of a vehicle. The brake master cylinder MC has an inlet connected to the brake pedal B via an input rod 12 so as to pressurize the brake fluid therein. In the illustrated example, a pressurizer or booster for changing the operating relationship (force and stroke) between the brake pedal B and the brake master cylinder MC may not be provided. The brake master cylinder MC includes a first piston G1. The first piston G1 is connected to the brake pedal B via the input rod 12 so as to move within the brake master cylinder MC when the brake pedal B is depressed. The first piston G1 pressurizes the brake fluid in a first chamber of the brake master cylinder MC, thereby causing the brake fluid to flow out from the first chamber to a first outlet 21. The second piston G2 of the brake master cylinder MC is not in direct mechanical engagement with the first piston G1 and the brake pedal B, but moves under the action of the fluid in the first chamber pressurized by the first piston G1. The second piston G2 pressurizes the brake fluid in the second chamber of the brake master cylinder MC, thereby outputting the brake fluid from the second chamber to the second outlet 23.

[0028] The DPB module 100 further includes a master cylinder reservoir MRSV having a fixed geometric configuration and a small volume. First and second master cylinder storage spaces MRSV1 and MRSV2 in the master cylinder reservoir MRSV are in fluid communication with the first and second chamber inlets 32 and 34 of the brake master cylinder MC, respectively, when the brake pedal B is actuated, until the pistons G1 and G2 of the brake master cylinder MC block the first and second chamber inlets 32 and 34. Also shown in the figure is a pedal stroke sensor PTS coupled to the brake pedal B or input rod 12, the pedal stroke sensor PTS operable to measure the travel of the brake pedal B.

[0029] The DPB module 100 further includes a pedal feel simulator PFS to provide a simulator circuit. The simulator circuit starts at the outlet side of the brake master cylinder MC (e.g., the first chamber outlet 21), ends at the master cylinder reservoir MRSV (e.g., the second master cylinder storage space MRSV2), and sequentially includes an operable normally-off simulator shutoff valve SSV, a filter F11, a pedal feel simulator PFS, and an inlet side of the brake master cylinder MC (e.g., the second chamber inlet 34). When the simulator shutoff valve SSV is controlled or energized to be on, a fluid communication is established between the outlet side of the brake master cylinder MC and the input side of the pedal feel simulator PFS. Brake fluid from the first chamber of the brake master cylinder MC passes through the first chamber outlet 21 and the simulator shutoff valve SSV and is then added to the input chamber of the pedal feel simulator PFS, pushing the piston of the pedal feel simulator PFS to reduce the volume of the output chamber of the pedal feel simulator PFS, and the brake fluid from the output chamber returns to the master cylinder reservoir MRSV (e.g. through the inlet side of the brake master cylinder MC).

[0030] The piston of the hydraulic cylinder HM can be driven (e.g., by a reduction gear mechanism and a ball screw shaft) by an electric machine DM to pressurize the brake fluid in the other side chamber, i.e., the high pressure chamber, of the hydraulic cylinder HM. The outlet side, i.e., the outlet 42, of the high pressure chamber of the hydraulic cylinder HM is connected to a fluid supply line for supplying brake fluid to the brake wheel cylinders by hydraulic cylinder shutoff valves PSV1, PSV2 connected in parallel with each other. As shown, the fluid supply lines for supplying fluid to the first pair of brake wheel cylinders WC1, WC2 and the second pair of brake wheel cylinders WC3, WC4 are identified as L1 and L2, respectively. In this way, when the hydraulic cylinder shutoff valves PSV1, PSV2 are turned on, the high pressure brake fluid from the high pressure chamber of the hydraulic cylinder HM can be supplied to the first and second brake wheel cylinders. Also, the first chamber outlet 21 (part of the simulator circuit) and the second chamber outlet 23) of the brake master cylinder MC and the outlet side of the second chamber, i.e., the second chamber outlet 23, are connected to the liquid supply lines L1, L2 via the operable master cylinder shutoff valves CSV1, CSV2, respectively, so that when the master cylinder shutoff valves CSV1, CSV2 are turned on, the pressurized brake fluid of the first and second chambers of the brake master cylinder MC can be supplied to the first and second pairs of brake wheel cylinders, respectively. The drawing also shows a master cylinder pressure sensor PS1 provided between the second chamber outlet 23 of the brake master cylinder MC and the second master cylinder shutoff valve CSV2 and operable to measure the pressure of the brake master cylinder MC, and a hydraulic cylinder pressure sensor PS2 provided between the outlet 42 of the hydraulic cylinder HM and the hydraulic cylinder shutoff valves PSV1, PSV2 and operable to measure the pressure of the high pressure chamber of the hydraulic cylinder HM. Although the brake master cylinder MC is shown in the drawings as having two chambers respectively used for the vehicle's two pairs of brake wheel cylinders, those skilled in the art will appreciate that this is not necessarily the case.In addition, the master cylinder reservoir MRSV is provided with two spaces MRSV1 and MRSV2 which are respectively connected to the two chambers of the brake master cylinder MC and have parts of their bottoms isolated from each other, but this is not essential.

[0031] The DPB module 100 further provides a hydraulic cylinder compensation line L11. One end of the hydraulic cylinder compensation line L11 is connected to a position close to the outlet 42 of the hydraulic cylinder HM, and the other end is connected to a master cylinder reservoir MRSV (e.g., the first master cylinder storage space MRSV1). The hydraulic cylinder compensation line L11 is provided with a one-way compensation valve PRV for one-way conduction from the master cylinder reservoir MRSV to the hydraulic cylinder HM, so that the brake fluid from the master cylinder reservoir MRSV can be added to the hydraulic cylinder HM via the hydraulic cylinder compensation line L11. The DPB module 100 further provides a hydraulic cylinder liquid inlet line L21. One end of the hydraulic cylinder liquid inlet line L21 is connected to the inlet 41 of the hydraulic cylinder HM, and the other end is connected to the master cylinder reservoir MRSV (e.g., the first master cylinder storage space MRSV1), so that the master cylinder reservoir MRSV can supply brake fluid to the hydraulic cylinder HM via the hydraulic cylinder liquid inlet line L21.

[0032] The ESP module 200 will be described below. In the ESP module 200, two fluid supply lines L1, L2 from the DPB module 100 are provided with normally-on system pressure control valves SC1, SC2, respectively, and then extend to normally-on fluid inlet valves IC1, IC2, IC3, IC4 of pairs of brake wheel cylinders WC1, WC2, WC3, WC4, so that the pressurized brake fluid from the DPB module 100 can be supplied to the pair of brake wheel cylinders.

[0033] The ESP module 200 includes a remote reservoir RRSV having an atmospheric pressure, for example, configured to communicate with the atmosphere. The brake fluid discharged from the normally-off fluid outlet valves OS1, OS2, OS3, OS4 of the brake wheel cylinders WC1, WC2, WC3, WC4 is directly discharged to the remote reservoir RRSV via fluid discharge lines L3, L4.

[0034] The ESP module 200 further includes compensation liquid supply lines L5 and L6 for each pair of brake wheel cylinders. The compensation liquid supply lines L5 and L6 allow the liquid drain lines L3 and L4 to be in fluid communication with the liquid supply lines L1 and L2, respectively. Specifically, the liquid drain lines L3, L4 are in communication with positions on the liquid supply lines L1, L2 between the system pressure control valves SC1, SC2 and the corresponding liquid inlet valves. The compensation liquid supply lines L5, L6 are provided with pumps P1, P2, respectively. The inlet side of each pump is in fluid communication with the remote reservoir RRSV, and the outlet side of each pump is in fluid communication with the liquid supply lines L1 and L2, but is turned off. The ESP module 200 includes a common electric machine EM that is used to control or drive the two pumps P1 and P2. The drawing also shows a pump pressure sensor PS3 arranged between the second system pressure control valve SC2 (or the first system pressure control valve SC1) and the liquid inlet valves IC3 and IC4 of the second pair of brake wheel cylinders (or the liquid inlet valve IC1 of IC2 of the first pair of brake wheel cylinders) and operable to measure the pressure at the output end of the second pump P2 (or the first pump P1).

[0035] In the illustrated embodiment, the remote reservoir RRSV of the ESP module 200 includes a first remote storage space RRSV1 for a first pair of brake wheel cylinders WC1 and WC2 in fluid communication with the liquid discharge line L3 of said pair of brake wheel cylinders, a second remote storage space RRSV2 for a second pair of brake wheel cylinders WC3 and WC4 in fluid communication with the liquid discharge line L4 of said pair of brake wheel cylinders, and a third remote storage space RRSV3. The first, second and third remote storage spaces RRSV1, RRSV2, RRSV3 are configured to be spaced apart from each other at the bottom and to be in fluid communication at a preset (liquid level) height, such that the brake fluid in any one of the three remote storage spaces can enter the other remote storage spaces only when the liquid level is higher than the preset height. In particular, the third remote storage space (RRSV3) and the first remote storage space (RRSV1), or the third remote storage space (RRSV3) and the second remote storage space (RRSV2) may be the same remote storage space, separated at the bottom from the second remote storage space (RRSV2) or the first remote storage space (RRSV1) by a preset height, and configured such that when the brake fluid in the first remote storage space (RRSV1) and the second remote storage space (RRSV2) is lower than the preset height, brake fluid remains in each space.

[0036] The remote reservoir RRSV, i.e., the first, second and third remote storage spaces RRSV1, RRSV2 and RRSV3, are configured so that their mounting positions on the vehicle are higher than the master cylinder reservoir MRSV of the DPB module 100, i.e., so that the height difference H between them is greater than 0. The third remote storage space RRSV3 is in fluid communication with the master cylinder reservoir MRSV by a pipe T of any form. With this configuration, the brake fluid in the third remote storage space RRSV3 can flow to the master cylinder reservoir MRSV by the action of gravity.

[0037] The hydraulic circuit diagram of the separated vehicle braking system according to the first exemplary configuration of the present application has been described above with reference to FIG. 1a. FIG. 1b is a hydraulic circuit diagram of the separated vehicle braking system according to the second exemplary configuration of the present application. The only difference between FIG. 1b and FIG. 1a is that the two pairs of brake wheel cylinders WC1 and WC2 and WC3 and WC4 of the ESP module in FIG. 1b share one fluid discharge line L3 for discharging brake fluid to a remote reservoir RRSV (e.g., the third remote storage space RRSV3), and a filter F3 is provided on the fluid discharge line L3. Hereinafter, the operation of the vehicle braking system shown in FIG. 1a will be described in detail with reference to FIG. 2 to FIG. 11, but the operation of the vehicle braking system shown in FIG. 1a is also applicable to the vehicle braking system shown in FIG. 1b. Each operation will be described only with respect to one pair of brake wheel cylinders of the vehicle (e.g., the second pair of brake wheel cylinders in FIG. 2 to FIG. 11, i.e., the right front wheel cylinder WC4 of the right front wheel and the left rear wheel cylinder WC3 of the left rear wheel). Those skilled in the art should understand that the following description of the second pair of brake wheel cylinders is also applicable to the first pair of brake wheel cylinders.

[0038] FIG. 2 shows a schematic diagram of a master cylinder fluid supply brake mode that may be provided by the vehicle braking system described above. The aforementioned mode may be implemented when the vehicle is not started. For example, the driver presses the brake pedal B when the vehicle is not started and neither the solenoid valve nor the electric machine is energized. In this case, the normally-on second master cylinder shutoff valve CSV2 between the brake master cylinder MC and the second liquid supply line L2 (the first liquid supply line L1 associated with the first pair of brake wheel cylinders is no longer mentioned in the following, L1 is completely identical to L2) is in the ON state, and the valves on the second liquid supply line L2 in the ESP module 200 (the normally-on second system pressure control valve SC2 and the normally-on liquid inlet valves IC3 and IC4 of the brake wheel cylinders) are all in the ON state. The normally-off liquid outlet valves OS3 and OS4 of the brake wheel cylinders are both in the OFF state. On the other hand, the second hydraulic cylinder shutoff valve PSV2 on the high pressure side of the hydraulic cylinder HM is in the OFF state, so the hydraulic cylinder HM is not operated and the communication between the outlet side of the high pressure chamber and the second liquid supply line L2 is cut off. Conversely, the pressurized brake fluid in the brake master cylinder MC enters the second liquid supply line L2 by the second master cylinder shutoff valve CSV2, passes through the second system pressure control valve SC2 and the liquid inlet valves IC3 and IC4 of the brake wheel cylinder, and enters the brake wheel cylinder, applying brake pressure to the brake wheel cylinder. MC is the pressure in the brake master cylinder MC.

[0039] The master cylinder fluid supply brake mode, as shown in FIG. 2, can also be executed when the control unit or power source of the braking system fails completely during normal vehicle running, and the implementation steps are the same as the master cylinder fluid supply brake mode in the off state described above. The flow path of the brake fluid in the master cylinder fluid supply brake mode can be expressed as master cylinder reservoir MRSV-brake master cylinder MC-master cylinder shutoff valve CSV2-second system pressure control valve SC2-fluid inlet valve IC3 / 4 of brake wheel cylinder-brake wheel cylinder WC3 / 4. The brake fluid in the above brake mode is from the brake master cylinder MC or master cylinder reservoir MRSV. When the brake pedal B is released, i.e., when the brake is released, the brake fluid in the brake wheel cylinder WC3 / 4 returns to the brake master cylinder MC or master cylinder reservoir MRSV along the original path.

[0040] The above description details the master cylinder fluid supply braking mode of the vehicle braking system of the present application. The hydraulic cylinder fluid supply braking mode and the ESP fluid supply braking mode of the vehicle braking system of the present application are described in detail below.

[0041] 3 to 5 show the pressurization, pressure maintenance and depressurization operations of the brake wheel cylinders of the vehicle braking system in the hydraulic cylinder fluid supply brake mode when the driver applies the brakes during normal vehicle running. In this mode, the simulator shutoff valve SSV is energized and turned on, and the pedal feel simulator PFS is connected to the first chamber of the brake master cylinder MC. The hydraulic cylinder shutoff valves PSV1, PSV2 are energized and turned on, and the hydraulic cylinder HM is connected to the fluid supply lines L1, L2. The master cylinder shutoff valves CSV1, CSV2 are energized and turned off, and the brake master cylinder MC is separated from the fluid supply lines L1, L2 (the solenoid valves in the figures are hatched to indicate "energized / powered"). First, referring to FIG. 3, the driver depresses the brake pedal B while the vehicle is running. In one embodiment, the pressurized brake fluid in the brake master cylinder MC (specifically in the first chamber) passes through the simulator shutoff valve SSV, the pedal feel simulator PFS, and the second chamber inlet 34 of the brake master cylinder MC, and returns to the master cylinder reservoir MRSV. In this case, the pedal feel simulator PFS and the brake master cylinder MC are separated from the second fluid supply line L2 in which the brake wheel cylinders are located, and the pedal feel simulator PFS utilizes a piston-spring mechanism that provides a feedback force to the brake pedal B to simulate the feeling that the brake wheel cylinders are pressurized. In another embodiment, when the driver presses the brake pedal B, the electric machine DM is actuated, and the actuated electric machine DM can pressurize the brake fluid in the high pressure chamber of the hydraulic cylinder HM to a target value (e.g., by a reduction mechanism and a ball screw shaft) according to a request from the control unit of the DPB module 100 and / or the vehicle driving assistance system. The high pressure brake fluid flows through the hydraulic cylinder shutoff valve PSV2 into the second fluid supply line L2, and then flows into the wheel brake cylinders WC3 and / or WC4, increasing the pressure of the corresponding wheel brake cylinder. This is the pressurization operation of the wheel brake cylinders. Figure 3 shows the pressure P MC and the pressure P of the hydraulic cylinder HMHM Two types of lines are shown, which indicate the RA is the lock pressure of the brake wheel cylinder of the rear axle of the vehicle. The above-mentioned pressurizing operation may be performed in response to a request from the control unit of the DPB module 100 or the vehicle driving assistance system when the brake pedal B is not depressed. For example, in the case of an additional function such as a traction control operation, the brake pedal is depressed and the brake pedal in the brake master cylinder MC is not pressurized. The electric machine DM in the DPB module 100 is operated in response to a request from the control unit of the DPB module 100 and / or the vehicle driving assistance system. The brake fluid in the high pressure chamber of the hydraulic cylinder HM is pressurized to a target value and flows into the second liquid supply line L2 through the second hydraulic cylinder shutoff valve PSV2, which is ON. In this case, one or both of the liquid inlet valves of the pair of brake wheel cylinders WC3, WC4 are maintained in an ON state or an OFF state in response to a request from the target brake wheel cylinder to which the supply of brake pressure is expected, and the other liquid inlet valve is maintained in the opposite state, thereby applying a braking force to the target wheel corresponding to the target brake wheel cylinder.

[0042] In the hydraulic cylinder fluid supply braking mode, when the brake pedal B starts to be released, the piston of the pedal feel simulator PFS returns under the action of the spring, and the first and second pistons G1, G2 of the brake master cylinder MC also return under the action of the corresponding return spring. In this case, the output cavity of the pedal feel simulator PFS absorbs brake fluid from the master cylinder reservoir RRSV, and the first chamber of the brake master cylinder MC absorbs brake fluid from the input cavity of the pedal feel simulator PFS. Meanwhile, the control unit of the DPB module 100 controls the electric machine DM to rotate in reverse according to the real-time feedback signals of the pedal stroke sensor PTS, the master cylinder pressure sensor PS1 and the rotor position sensor RPS. The electric machine DM drives the piston of the hydraulic cylinder HM to return to its original position in a controlled manner. The brake fluid in the brake wheel cylinder returns into the hydraulic cylinder HM, and the brake pressure of the brake wheel cylinder is gradually removed in a controlled manner. When the amount of brake fluid released by the brake wheel cylinder is not sufficient to fill the hydraulic cylinder HM, the hydraulic cylinder HM, by means of the continuous return of its piston, is able to generate a negative pressure in its high pressure chamber and absorbs an amount of compensation fluid from the first master cylinder storage space MRSV1 by the hydraulic cylinder compensation line L11.

[0043] Based on FIG. 3, if the brake pedal B is not released, but instead the pressure in the brake wheel cylinder continues to increase (e.g., by further depressing the brake pedal B) in addition to the pressurizing action described above, then, with reference to FIG. 4, as the pressure in the brake wheel cylinder increases, the locking pressure P of the wheel cylinder of the rear axle of the vehicle increases. RA is usually the locking pressure P of the wheel cylinder of the front axle FASince the pressure of the brake fluid in the (left rear) brake wheel cylinder WC3 reaches the rear axle lock pressure first, the fluid inlet valve IC3 of the brake wheel cylinder WC3 is automatically energized to cut off the inflow of brake fluid, while the (right front) brake wheel cylinder WC4 continues to be filled with high pressure brake fluid from the hydraulic cylinder HM, as shown in the figure. This is the pressure maintaining operation of the brake wheel cylinders. Different diameters or types of lines in the figure represent different pressures in different pipelines (or pipeline sections).

[0044] Based on FIG. 4, if the brake pedal B is not released and instead the brake wheel cylinder pressure continues to increase (e.g., by further depressing the brake pedal B) in addition to the pressure maintaining action described above, then, with reference to FIG. 5, the brake fluid pressure in the (right front) brake wheel cylinder WC4 also increases to the locking pressure P FA In this case, the fluid inlet valve IC4 of the wheel brake cylinder WC4 is also automatically energized and turned off. Meanwhile, the fluid outlet valves OS3 and OS4 of the wheel brake cylinders WC3 and WC4 are both energized and turned on, the brake fluid in the wheel brake cylinders WC3 and WC4 is discharged to the remote reservoir RRSV, specifically the second remote storage space RRSV2, via the fluid discharge line L4, and the pressure in the wheel brake cylinders WC3 and WC4 drops below the lock pressure. This is the depressurizing operation of the wheel brake cylinders. The pressurizing operation (Fig. 3), pressure maintaining operation (Fig. 4), and depressurizing operation (Fig. 5) described above constitute a typical cycle of the wheel antilock control function.

[0045] The braking operation after the vehicle starts, which is shown diagrammatically in Figures 3 to 5, utilizes the hydraulic cylinder fluid supply brake mode of the vehicle braking system described above, and the flow path of the brake fluid can be represented as follows: hydraulic cylinder HM-second hydraulic cylinder shutoff valve PSV2-second system pressure control valve SC2-brake wheel cylinder liquid inlet valve IC3 / 4-brake wheel cylinder WC3 / 4-brake wheel cylinder liquid outlet valve OS3 / 4-remote reservoir RRSV.

[0046] During the execution of the cycles of Figures 3 to 5, the brake fluid in the high pressure chamber of the hydraulic cylinder HM is continuously supplied to the brake wheel cylinder and then discharged to the remote reservoir RRSV. Since the high pressure chamber of the hydraulic cylinder HM is not replenished with brake fluid and the brake fluid gradually decreases, the pressure P in the second fluid supply line L2 HM decreases. When the pressure decreases to a preset value and / or when the output value of the rotor position sensor RPS reaches a preset value, the common electric machine EM of the ESP module 200 is operated and the second pump P2 starts to operate. The brake fluid in the remote reservoir RRSV (specifically, the second remote storage space RRSV2 in the figure) is drawn off. The brake fluid pressurized by the second pump P2 is added to the second liquid supply line L2. FIG. 6 shows a scenario in which liquid supply compensation is performed when the above-mentioned situation occurs in the pressure reduction process of FIG. 5 (the only difference is that the second pump P2 is operated and the brake fluid flows as shown by the arrows). In this case, since the liquid outlet valves OS3 and OS4 of the brake wheel cylinders are in the ON state, not only the brake fluid in the remote reservoir RRSV is drawn off to the second liquid supply line L2 by the second pump P2, but also the brake fluid discharged from the brake wheel cylinders WC3 and WC4 is drawn off to the second liquid supply line L2 for compensation. In the pressurizing and holding operation of Fig. 3 and Fig. 4, when the above compensation occurs and OS3 and OS4 of the brake wheel cylinders WC3 and WC4 are in the OFF state, only the brake fluid in the remote reservoir RRSV is drawn by the second pump P2 and added to the second liquid supply line L2, and the pressure in the second liquid supply line L2 is held. In the illustrated embodiment, the second system pressure control valve SC2 on the second liquid supply line L2 is in a state in which its opening degree is controllable (for example, the voltage of its electromagnetic coil is controlled by pulse width modulation). In this way, the lock pressure P of the brake wheel cylinders of the front axle is controlled between the second system pressure control valve SC2 and the liquid inlet valves WC3 and WC4. FAIn addition to being able to maintain a pressure higher than the pressure in the hydraulic cylinder HM, it is also possible to compensate for the brake fluid loss between the second system pressure control valve SC2 and the hydraulic cylinder HM. Optionally, in the compensation state described above, the second system pressure control valve SC2 may be in a full-on state.

[0047] When the pressurization process of FIG. 3 is performed and the brake pressure desired by the driver, as indicated by the signals of the pedal stroke sensor PTS and the master cylinder pressure sensor PS1, exceeds the maximum pressure that the hydraulic cylinder HM can supply, the second system pressure control valve SC2 is energized and completely turned off. The common electric machine EM of the ESP module 200 is actuated and the second pump P2 starts to operate. The brake fluid in the remote reservoir RRSV (specifically, the second remote storage space RRSV2 in the figure) is drawn off. The brake fluid pressurized by the second pump P2 is added to the second liquid supply line L2. FIG. 7 shows a scenario in which liquid supply compensation is performed when the above-mentioned situation occurs in the pressurization process of FIG. 3 (the only difference is that the second pump P2 and the second system pressure control valve SC2 are operated and the brake fluid flows as shown by the arrows). The pressure between the second system pressure control valve SC2 and the liquid inlet valves WC3 and WC4 is equal to the lock pressure P of the brake wheel cylinders of the front axle. FA When the pressure difference between the upstream side and the downstream side of the second system pressure control valve SC2 is larger than the pressure difference between the upstream side and the downstream side of the second system pressure control valve SC2, the pressure difference between the upstream side and the downstream side of the second system pressure control valve SC2 can be balanced.

[0048] 6 and 7 show the ESP fluid supply braking mode that can be provided by the above-mentioned vehicle braking system, and the flow path of the brake fluid can be represented as remote reservoir RRSV-second pump P2-liquid inlet valve IC3 / 4 of the brake wheel cylinder-brake wheel cylinder WC3 / 4. The brake fluid from the liquid outlet valve OS3 / 4 of the brake wheel cylinder to the remote reservoir RRSV belongs to the decompression operation of the brake wheel cylinder in FIG.

[0049] 8a to 8d show a scenario in which the pressure in the brake wheel cylinders is gradually released in a controlled manner. For example, when the brake pedal B starts to be released, the piston of the pedal feel simulator PFS returns under the action of a spring, and the first and second pistons G1, G2 of the brake master cylinder MC also return under the action of their corresponding return springs. In this case, the output cavity of the pedal feel simulator PFS absorbs brake fluid from the master cylinder reservoir RRSV, and the first chamber of the brake master cylinder MC absorbs brake fluid from the input cavity of the pedal feel simulator PFS. On the other hand, when the pressure value measured by the pump pressure sensor PS3 is greater than the pressure value measured by the hydraulic cylinder sensor PS2 by a preset value, the second system pressure control valve SC2 is energized and its opening is controlled in real time (for example, a pulse width modulated voltage is applied in real time), as shown in FIG. 8a. When the difference between the pressure value measured by the pump pressure sensor PS3 and the pressure value measured by the hydraulic cylinder sensor PS2 is equal to or less than the above-mentioned preset value, the second system pressure control valve SC2 is de-energized and turned on, and then the control unit of the DPB module 100 controls the electric machine DM to rotate in reverse according to the real-time feedback signals of the pedal travel sensor PTS, the master cylinder pressure sensor PS1 and the rotor position sensor RPS. The electric machine DM drives the piston of the hydraulic cylinder HM to return gradually in a controlled manner, as shown in Fig. 8b. When the amount of brake fluid released by the brake wheel cylinder is not enough to fill the hydraulic cylinder HM, i.e., when the value of the master cylinder pressure sensor PS1 is 0 but the value of the rotor position sensor RPS is not 0, the hydraulic cylinder HM can utilize the continued return of its piston to generate negative pressure in its high pressure chamber, and absorb a certain amount of compensation fluid from the first master cylinder storage space MRSV1 through the hydraulic cylinder compensation line L11, as shown in Fig. 8c. When the piston of the hydraulic cylinder HM returns to the 0 position, the pressure P HMand pressure P4 reaches atmospheric pressure P0, and the braking system prepares for the next braking. When the amount of brake fluid released by the brake wheel cylinder is greater than the maximum capacity of the high pressure chamber of the hydraulic cylinder HM, i.e., when the piston of the hydraulic cylinder HM returns to its initial position, the pressure value measured by the hydraulic cylinder pressure sensor PS2 and / or the pump pressure sensor PS3 is still greater than a certain preset value, the opening degree of the liquid inlet valve IC3 and / or the liquid inlet valve IC4 is controlled in real time (e.g., a pulse width modulated voltage is applied in real time) and / or the liquid outlet valve OS3 and / or the liquid outlet valve OS4 are energized to turn on, as shown in Fig. 8d. When the pressure value measured by the hydraulic cylinder pressure sensor PS2 and / or the pump pressure sensor PS3 is less than a certain preset value, the liquid outlet valves OS3 and OS4 are de-energized to turn off, and the braking system prepares for the next braking. In this way, the brake pressure in the brake wheel cylinders WC3 and WC4 can be gradually released in a controlled manner according to the real-time feedback signals of the pedal stroke sensor PTS and the master cylinder pressure sensor PS1.

[0050] The automatic vehicle holding function of the present invention can not only prevent the vehicle from rolling when the driver of the vehicle releases the brake pedal when the vehicle is in a starting and stopping state (for example, waiting for the green light at an intersection), but also can automatically remove the air that may be mixed into the brake fluid when the brake wheel cylinder is released. Referring to FIG. 9, the implementation steps are as follows: In the first step, before the driver releases the brake pedal B, the second system pressure control valve SC2 can be energized and the second liquid supply line L2 can be cut off. In the second step, the driver releases the brake pedal B, and the piston in the hydraulic cylinder HM is driven back by the reverse rotation of the electric machine DM of the DPB module 100, and the hydraulic cylinder HM uses the action of atmospheric pressure to add brake fluid through the hydraulic cylinder compensation line L11, so that the pressure of the brake wheel cylinder can be maintained for a long time when the pressure of the hydraulic cylinder HM is continuously reduced. In the third step, when the driver depresses the accelerator pedal (accelerator), the opening degree of the liquid inlet valve IC3 and / or the liquid inlet valve IC4 is controlled in real time (for example, a pulse width modulated voltage is applied in real time), and / or the liquid outlet valve OS3 and / or the liquid outlet valve OS4 is energized and turned on, so that the brake fluid in the brake wheel cylinders WC3 and WC4 and the air that may be mixed therein are discharged to the remote reservoir RRSV through the liquid outlet valves OS3 and OS4 and the liquid discharge line L4, and the vehicle can start smoothly, and in the fourth step, the second system pressure control valve SC2 and the liquid inlet valves IC3 and IC4 are de-energized and turned on, and the liquid outlet valves OS3 and OS4 are de-energized and turned off. Since the remote reservoir RRSV communicating with the atmosphere is at atmospheric pressure, the air discharged from the brake wheel cylinders rises above the liquid surface of the brake fluid because it has a density lower than that of the brake fluid, thereby achieving an automatic exhaust function.

[0051] The above description details the hydraulic cylinder fluid supply braking mode and the ESP fluid supply braking mode of the vehicle braking system of the present application. The first and second redundant braking modes of the vehicle braking system of the present application are described in detail below.

[0052] After the vehicle is started, the control unit of the DPB module 100 also periodically checks whether the electric machine DM, the rotor position sensor RPS, the master cylinder shutoff valves CSV1 and CSV2, the hydraulic cylinder shutoff valves PSV1 and PSV2, and the hydraulic cylinder pressure sensor PS2 are operating normally; if it is detected that one or a certain combination of the components is faulty and therefore cannot operate normally, the DPB module 100 and the ESP module 200 enter a first redundant brake mode, as shown in FIG. 10. In this mode, the second system pressure control valve SC2 is energized and turned off. The second liquid supply line L2 is blocked. The simulator shutoff valve SSV is energized and turned on. The pedal feel simulator PFS communicates with the first chamber MC1 of the brake master cylinder. When the brake pedal B is pressed, the brake fluid in the first and second chambers of the brake master cylinder MC is pressurized. The brake fluid in the second chamber MC2 is retained in the second chamber MC2 by the blocking action of the second system pressure control valve SC2. The brake fluid in the first chamber MC1 passes through the first chamber outlet 21 and the simulator shutoff valve SSV, and then is added to the input cavity of the pedal feel simulator PFS. Correspondingly, the brake fluid in the output cavity of the pedal feel simulator PFS flows back to the master cylinder reservoir MRSV. Meanwhile, the control unit of the DPB module 100 controls the common electric machine EM of the ESP module 200 to drive and operate the second pump P2 according to the real-time feedback signals of the pedal travel sensor PTS and the master cylinder pressure sensor PS1. The brake fluid in the second remote storage space RRSV2 is drawn by the second pump P2 and pressurized to a target pressure. The aforementioned target pressure is measured by the pump pressure sensor PS3 and sent to the control units of the ESP module and the DPB module to achieve closed-loop control of the output pressure of the second pump P2. The pressurized brake fluid is supplied to the wheel brake cylinders WC3 and WC4 connected to the second fluid supply line L2 through the fluid inlet valves IC3 and IC4, respectively, thereby achieving the pressurization operation of the wheel brake cylinders.The above is the pressurizing operation of the first redundant brake mode. The pressurizing operation described above may be performed in response to a request from the control unit of the DPB module 100 and / or the control unit of the ESP module 200 and / or the vehicle driving assistance system when the brake pedal B is not depressed. A typical cycle of the wheel anti-lock control in the first redundant brake mode also consists of a pressurizing operation, a pressure maintaining operation, and a pressure reducing operation. This pressurizing operation is realized by the pressurizing operation of the first redundant brake mode. This pressure maintaining operation and pressure reducing operation are respectively consistent with the pressure maintaining operation and pressure reducing operation of the cylinder hydraulic cylinder fluid supply brake mode described above.

[0053] In the first redundant brake mode, when the brake pedal B begins to be gradually released or when the brake pressure demand from the control unit of the DPB module 100 and / or the control unit of the ESP module 200 and / or the vehicle driving assistance system gradually decreases, the opening degree of one or two of the first and / or second pairs of liquid inlet valves is controlled in real time (e.g., a pulse width modulated voltage is applied in real time) and / or one or two of the first and / or second pairs of liquid outlet valves are energized and turned on, thereby gradually releasing the brake pressure in the first and second pairs of brake wheel cylinders according to the real time feedback signals of the pedal travel sensor PTS and the master cylinder pressure sensor PS1.

[0054] After the vehicle is started, the control unit of the DPB module 100 also periodically checks whether the simulator isolation valve SSV is operating normally, and once it is detected that the simulator isolation valve SSV is faulty and therefore cannot operate normally, and the DPB module 100 and the ESP module 200 are in the first redundant braking mode, the vehicle braking system executes the second redundant braking mode, as shown in FIG. 11. The second system pressure control valve SC2 is energized and turned off, and the second liquid supply line L2 is cut off. When the brake pedal B is depressed, the brake fluid in the first and second chambers of the brake master cylinder MC is pressurized. The brake fluid in both chambers is kept in the respective chambers by the cutoff action of the system pressure control valves SC1, SC2. Meanwhile, the control unit of the DPB module 100 controls the common electric machine EM to drive and operate the second pump P2 according to the real-time feedback signals of the pedal travel sensor PTS and the master cylinder pressure sensor PS1. The brake fluid in the second remote storage space RRSV2 is drawn by the second pump P2 and pressurized to a target pressure. The aforementioned output pressure is measured by the pump pressure sensor PS3 and sent to the control units of the ESP module and the DPB module so as to achieve closed-loop control of the output pressure of the second pump P2. The pressurized brake fluid is supplied to the brake wheel cylinders WC3 and WC4 connected to the second liquid supply line L2 via the liquid inlet valves IC3 and IC4, respectively, thereby achieving the pressurization operation of the brake wheel cylinders. The above is the pressurization operation of the second redundant brake mode. The above pressurization operation may also be performed in response to a request from the control unit of the DPB module 100 and / or the control unit of the ESP module 200 and / or the vehicle driving assistance system when the brake pedal B is not depressed. A typical cycle of the wheel antilock control in the second redundant brake mode also consists of pressurization, pressure holding, and depressurization operations. This pressurization operation is realized by the pressurization operation of the second redundant brake mode.The pressure maintaining and reducing operations correspond to the pressure maintaining and reducing operations, respectively, of the cylinder hydraulic cylinder fluid supply braking mode described above.

[0055] In the second redundant brake mode, when the brake pedal B begins to be gradually released or when the brake pressure demand from the control unit of the DPB module 100 and / or the control unit of the ESP module 200 and / or the vehicle driving assistance system gradually decreases, the opening degree of one or two of the first and / or second pairs of liquid inlet valves is controlled in real time (e.g., a pulse width modulated voltage is applied in real time) and / or one or two of the first and / or second pairs of liquid outlet valves are energized and turned on, thereby gradually releasing the brake pressure in the first and second pairs of brake wheel cylinders according to the real time feedback signals of the pedal travel sensor PTS and the master cylinder pressure sensor PS1.

[0056] Above, the principle of the vehicle braking system according to the first exemplary configuration of the present invention has been described in detail. In particular, the vehicle braking system provides three different braking modes with three different fluid supply sources. The aforementioned three braking modes can not only provide all the functions of the existing braking system, but also provide additional functions such as automatic exhaust, which can be achieved by the common fluid exhaust operation in the aforementioned three braking modes (the brake fluid in the brake wheel cylinder is exhausted to a remote reservoir having atmospheric pressure through a fluid outlet valve). For the aforementioned braking system, when the hydraulic cylinder fluid supply braking mode fails and therefore cannot operate normally, the ESP fluid supply braking mode and the master cylinder fluid supply braking mode can still provide the braking function. When the pressure of the brake fluid or the hydraulic cylinder HM is insufficient, the ESP fluid supply braking mode can still normally provide the brake pressure required for braking to the brake wheel cylinder. Therefore, it can be seen that the capacity of the hydraulic cylinder HM and the electric machine DM of the aforementioned braking system does not need to be designed to be very large, thereby also achieving the purpose of reducing the cost and saving the space.

[0057] As mentioned above, the liquid drain line of the brake wheel cylinder of the present application is configured to drain the brake fluid of the brake wheel cylinder directly to the remote reservoir RRSV having atmospheric pressure, so that the liquid drain line is simpler and always under atmospheric pressure, and there is no need to provide an accumulator component. The vibration of the brake pedal B caused by the drainage of the brake fluid is no longer present in the vehicle's brake pedal and the hydraulic cylinder HM adjacent thereto, thereby improving the driver's driving experience. Furthermore, technical problems (leakage, corrosion, etc.) associated with accumulator components are eliminated, and costs are reduced accordingly. In addition, since the suction sides of the pumps P1 and P2 of the ESP module 200 of the vehicle braking system described above are connected to the remote reservoir RRSV having atmospheric pressure, the sucked-in brake fluid is no longer in a high-pressure state. In one aspect, components such as a high-pressure switching valve (HSV) and a one-way fluid suction valve (BSV) are not required, thereby reducing costs. In another aspect, the length of the path through which the brake fluid in the remote reservoir RRSV is supplied to the brake wheel cylinders through the pumps P1 and P2 is significantly shortened, thereby improving braking efficiency.

[0058] The DPB module 100 of the vehicle braking system of the present application includes a master cylinder reservoir MRSV with a fixed capacity. The capacity of the master cylinder reservoir MRSV may be designed to be small, thereby achieving the technical objective of reducing the volume of the DPB module and meeting the required mounting space. The foregoing is highly advantageous since the space in the vehicle firewall is limited. In addition, since a customer-customized reservoir with different parameters (e.g., capacity and geometric structure) is changed into a master cylinder reservoir MRSV with a fixed geometric structure (especially, capacity), the structure and size of the interface of the components related thereto are fixed and do not need to be changed as the customer's requirements for the master cylinder reservoir change, thereby providing versatility of the system.

[0059] When the mounting position of the remote reservoir RRSV of the ESP module 200 is higher than the master cylinder reservoir, the mounting position is higher than the road surface, so that the possibility of corrosion and muddy water intrusion can be reduced, especially in harsh road conditions. The remote reservoir RRSV only needs to be at atmospheric pressure, can communicate with the atmosphere, has low requirements on the mounting position, and therefore can have a large capacity to compensate for the limited capacity problem of the master cylinder reservoir MRSV of the DPB module 100, thereby meeting various customers' requirements on reservoir capacity.

[0060] The first and second exemplary configurations of the vehicle braking system of the present application have been described above with reference to Figs. 1a, 1b and 2 to 11. Figs. 12a and 12b are third and fourth exemplary configurations of the vehicle braking system. The third and fourth exemplary configurations of Figs. 12a and 12b differ from the first and second exemplary configurations of Figs. 1a and 1b only in the following respects: a hydraulic cylinder compensation line provided with a normally-off hydraulic cylinder compensation valve PIV is added between the high pressure side (chamber) of the hydraulic cylinder HM and the master cylinder reservoir MRSV, and a hydraulic cylinder compensation line provided with a one-way compensation valve PRV located between the hydraulic cylinder HM and the master cylinder reservoir MRSV is eliminated. The other liquid lines are similar to the liquid lines in both Figs. 1a and 1b, and the details will not be described again here.

[0061] 13, corresponding to FIG 2, shows a braking process of the vehicle braking system of the third exemplary configuration in a master cylinder fluid supply braking mode, diagrammatically showing the master cylinder reservoir MRSV - brake master cylinder MC - master cylinder shutoff valve CSV2 - second system pressure control valve SC2 - brake wheel cylinder fluid inlet valves IC3 / 4 - brake wheel cylinders WC3 / 4, the details of which will not be repeated here.

[0062] 14 to 16, corresponding to FIGS. 3 to 5, illustrate schematic diagrams of the pressurization, pressure maintenance and depressurization operations of the brake wheel cylinders when the vehicle braking system of the third exemplary configuration performs braking in the hydraulic cylinder fluid supply braking mode, as follows: hydraulic cylinder HM-hydraulic cylinder shutoff valve PSV2-second system pressure control valve SC2-brake wheel cylinder liquid inlet valve IC3 / 4-brake wheel cylinder WC3 / 4-brake wheel cylinder liquid outlet valve OS3 / 4-remote reservoir RRSV.

[0063] FIG. 17 corresponds to FIG. 6 and illustrates a schematic scenario of a brake fluid shortage scenario in the hydraulic cylinder HM in the hydraulic cylinder fluid supply braking mode of the vehicle braking system of the third exemplary configuration. The pump P2 of the ESP module 200 is activated. The pump P2 simultaneously draws and pressurizes the brake fluid in the second remote storage space RRSV2 and the brake fluid drained from the brake wheel cylinder. The pressurized pressure P4 is the brake pressure P provided by the hydraulic cylinder HM. HM Brake fluid is then added to the fluid inlet end of the fluid inlet valve of the brake wheel cylinder, thus maintaining the long term pressure build-pressure hold-pressure release cycle of the braking process.

[0064] 18 corresponds to FIG. 7 and illustrates a schematic scenario of a brake pressure shortage in the hydraulic cylinder HM in the hydraulic cylinder fluid supply braking mode of the vehicle braking system of the third exemplary configuration. The pump P2 of the ESP module 200 is activated. The pump P2 draws and pressurizes the brake fluid in the second remote storage space RRSV2. The pressurized pressure P4 is the brake pressure P provided by the hydraulic cylinder HM. HM Then, brake fluid is added to the liquid inlet end of the liquid inlet valve of the brake wheel cylinder. In this way, the need for high final pressure in the braking process is met.

[0065] 19, corresponding to FIG. 8, shows a schematic scenario enabling the pressure in the brake wheel cylinder to be gradually released in a controlled manner in a vehicle braking system according to the third exemplary configuration. For example, when the brake pedal B starts to be gradually released, when the pressure value measured by the pump pressure sensor PS3 is greater than the pressure value measured by the hydraulic cylinder sensor PS2 by a preset value, the second system pressure control valve SC2 is energized and its opening is controlled in real time (e.g., a pulse width modulated voltage is applied in real time) as shown in FIG. 19a. When the difference between the pressure value measured by the pump pressure sensor PS3 and the pressure value measured by the hydraulic cylinder sensor PS2 is equal to or less than the aforementioned pressure value, the second system pressure control valve SC2 is de-energized and turned on, and then the control unit of the DPB module 100 controls the electric machine DM to rotate in reverse according to the real time feedback signals of the pedal travel sensor PTS, the master cylinder pressure sensor PS1 and the rotor position sensor RPS. The electric machine DM drives the piston of the hydraulic cylinder HM to return gradually in a controlled manner, as shown in Fig. 19b. When the amount of brake fluid released by the brake wheel cylinder is not enough to fill the hydraulic cylinder HM, i.e., when the value of the master cylinder pressure sensor PS1 is 0 but the value of the rotor position sensor RPS is not 0, the hydraulic cylinder compensation valve PIV is energized and turned on, and the hydraulic cylinder HM can utilize the continued return of its piston to generate negative pressure in its high pressure chamber, and absorb a certain amount of compensation fluid from the second master cylinder storage space MRSV2 through the hydraulic cylinder compensation line L11, as shown in Fig. 19c. When the piston of the hydraulic cylinder HM returns to the 0 position, the pressure P of the hydraulic cylinder HM is supplied to the hydraulic cylinder HM through the hydraulic cylinder liquid inlet line L21. HMand pressure P4 reaches atmospheric pressure P0, and the braking system prepares for the next braking. When the amount of brake fluid released by the brake wheel cylinder is greater than the maximum capacity of the high pressure chamber of the hydraulic cylinder HM, i.e., when the piston of the hydraulic cylinder HM returns to its initial position, the pressure value measured by the hydraulic cylinder pressure sensor PS2 and / or the pump pressure sensor PS3 is still greater than a certain preset value, the opening degree of the liquid inlet valve IC3 and / or the liquid inlet valve IC4 is controlled in real time (e.g., a pulse width modulated voltage is applied in real time) and / or the liquid outlet valve OS3 and / or the liquid outlet valve OS4 are energized to turn on, as shown in Fig. 19d. When the pressure value measured by the hydraulic cylinder pressure sensor PS2 and / or the pump pressure sensor PS3 is less than a certain preset value, the liquid outlet valves OS3 and OS4 are de-energized to turn off, and the braking system prepares for the next braking. In this way, the brake pressure in the brake wheel cylinders WC3 and WC4 can be gradually released in a controlled manner according to the real-time feedback signals of the pedal stroke sensor PTS and the master cylinder pressure sensor PS1.

[0066] FIG. 20 corresponds to FIG. 9 and illustrates a scenario in which the automatic exhaust of the remote reservoir is performed when the automatic vehicle holding function is terminated in the vehicle braking system of the third exemplary configuration. In the second step, the hydraulic cylinder compensation valve PIV is energized and turned on, and the hydraulic cylinder HM uses the action of the atmospheric pressure to add brake fluid through the hydraulic cylinder compensation line L11. The above liquid addition operation can be expressed as master cylinder reservoir MRSV-hydraulic cylinder compensation valve PIV-hydraulic cylinder HM. The other operation steps are consistent with the operation steps in FIG. 9, and the details will not be described again here.

[0067] Figure 21 corresponds to Figure 10 and shows a schematic diagram of the pressurizing operation performed by the vehicle braking system of the third exemplary configuration in the first redundant braking mode, and the operation procedure is consistent with that of Figure 10. The details will not be described again here.

[0068] 22 corresponds to FIG 11 and shows a schematic diagram of the pressurizing operation performed by the vehicle braking system of the third exemplary configuration in the second redundant braking mode, and the operation procedure is consistent with that of FIG 11. The details will not be described again here.

[0069] 23a and 23b are fifth and sixth exemplary configurations of a vehicle braking system. The fifth and sixth exemplary configurations of Fig. 23a and 23b differ from the first and second exemplary configurations of Fig. 1a and 1b only in the following respects: the hydraulic cylinder compensation line located between the hydraulic cylinder HM and the master cylinder reservoir MRSV and provided with the one-way compensation valve PRV is eliminated, and the first and second remote storage spaces RRSVI and RRSV2 of the remote reservoir RRSV are allowed to be in fluid communication with the liquid supply lines L1 and L2 of the first and second pairs of brake wheel cylinders, respectively, specifically, connected to the upstream (or inlet) sides of the system pressure control valves SC1 and SC2 on the liquid supply lines L1 and L2 via the one-way compensation valves PRV1 and PRV2. These are the hydraulic cylinder compensation lines L11 and L12. The other liquid lines are similar to those in both Fig. 1a and 1b, and the details will not be described again here.

[0070] 2 and illustrates a schematic diagram of the braking process of the vehicle braking system in the fifth exemplary configuration in a master cylinder fluid supply braking mode, in the order of master cylinder reservoir MRSV-brake master cylinder MC-master cylinder shutoff valve CSV2-second system pressure control valve SC2-brake wheel cylinder fluid inlet valves IC3 / 4-brake wheel cylinders WC3 / 4, the details of which will not be repeated here.

[0071] Figures 25 to 27 correspond to Figures 3 to 5 and show schematic diagrams of pressurizing, maintaining and depressurizing operations of the brake wheel cylinder when the vehicle braking system of the fifth exemplary configuration performs braking in the hydraulic cylinder fluid supply braking mode, as follows: hydraulic cylinder HM-hydraulic cylinder shutoff valve PSV2-second system pressure control valve SC2-brake wheel cylinder liquid inlet valve IC3 / 4-brake wheel cylinder WC3 / 4-brake wheel cylinder liquid outlet valve OS3 / 4-remote reservoir RRSV.

[0072] FIG. 28 corresponds to FIG. 6 and illustrates a schematic scenario of a brake fluid shortage scenario in the hydraulic cylinder HM in the hydraulic cylinder fluid supply braking mode of the vehicle braking system of the fifth exemplary configuration. The pump P2 of the ESP module 200 is activated. The pump P2 simultaneously draws and pressurizes the brake fluid in the second remote storage space RRSV2 and the brake fluid drained from the brake wheel cylinder. The pressurized pressure P4 is the brake pressure P provided by the hydraulic cylinder HM. HM Brake fluid is then added to the fluid inlet end of the fluid inlet valve of the brake wheel cylinder, thus maintaining the long term pressure build-pressure hold-pressure release cycle of the braking process.

[0073] 29 corresponds to FIG. 7 and illustrates a schematic scenario of a brake pressure shortage in the hydraulic cylinder HM in the hydraulic cylinder fluid supply braking mode of the vehicle braking system of the fifth exemplary configuration. The pump P2 of the ESP module 200 is activated. The pump P2 draws and pressurizes the brake fluid in the second remote storage space RRSV2. The pressurized pressure P4 is the brake pressure P provided by the hydraulic cylinder HM. HM Then, brake fluid is added to the liquid inlet end of the liquid inlet valve of the brake wheel cylinder. In this way, the need for high final pressure in the braking process is met.

[0074] FIG. 30 corresponds to FIG. 8 and illustrates a scenario that allows the pressure in the brake wheel cylinder to be gradually released in a controlled manner in a vehicle braking system according to the fifth exemplary configuration. For example, when the brake pedal B starts to be gradually released, when the pressure value measured by the pump pressure sensor PS3 is greater than the pressure value measured by the hydraulic cylinder sensor PS2 by a preset value, the second system pressure control valve SC2 is energized and its opening is controlled in real time (e.g., a pulse width modulated voltage is applied in real time) as shown in FIG. 30(a). When the difference between the pressure value measured by the pump pressure sensor PS3 and the pressure value measured by the hydraulic cylinder sensor PS2 is equal to or less than the above-mentioned preset value, the second system pressure control valve SC2 is de-energized and turned on, and then the control unit of the DPB module 100 controls the electric machine DM to rotate in reverse according to the real-time feedback signals of the pedal travel sensor PTS, the master cylinder pressure sensor PS1, and the rotor position sensor RPS. The electric machine DM drives the piston of the hydraulic cylinder HM to return gradually in a controlled manner, as shown in Fig. 30b. When the amount of brake fluid released by the brake wheel cylinder is not enough to fill the hydraulic cylinder HM, i.e. when the value of the master cylinder pressure sensor PS1 is 0 but the value of the rotor position sensor RPS is not 0, the hydraulic cylinder HM can use the continued return of its piston to generate a negative pressure in its high pressure chamber, as shown in Fig. 30c, and absorb a certain amount of compensation fluid from the remote reservoir RRSV through the hydraulic cylinder compensation lines L11 and L12. When the piston of the hydraulic cylinder HM returns to the 0 position, the pressure P of the hydraulic cylinder HM is supplied to the hydraulic cylinder HM through the hydraulic cylinder liquid inlet line L21. HMand pressure P4 reaches atmospheric pressure P0, and the braking system prepares for the next braking. When the amount of brake fluid released by the brake wheel cylinder is greater than the maximum capacity of the high pressure chamber of the hydraulic cylinder HM, i.e., when the piston of the hydraulic cylinder HM returns to its initial position, the pressure value measured by the hydraulic cylinder pressure sensor PS2 and / or the pump pressure sensor PS3 is still greater than a certain preset value, the opening degree of the liquid inlet valve IC3 and / or the liquid inlet valve IC4 is controlled in real time (e.g., a pulse width modulated voltage is applied in real time) and / or the liquid outlet valve OS3 and / or the liquid outlet valve OS4 are energized to turn on, as shown in Fig. 30d. When the pressure value measured by the hydraulic cylinder pressure sensor PS2 and / or the pump pressure sensor PS3 is less than a certain preset value, the liquid outlet valves OS3 and OS4 are de-energized to turn off, and the braking system prepares for the next braking. In this way, the brake pressure in the brake wheel cylinders WC3 and WC4 can be gradually released in a controlled manner according to the real-time feedback signals of the pedal stroke sensor PTS and the master cylinder pressure sensor PS1.

[0075] 31 corresponds to FIG. 9 and shows a schematic scenario of performing automatic exhaust by remote reservoir when automatic vehicle holding function is terminated in the vehicle braking system of the fifth exemplary configuration. In the second step, hydraulic cylinder HM adds brake fluid through hydraulic cylinder compensation lines L11 and L12 by utilizing the effect of atmospheric pressure. The above-mentioned liquid adding operation can be expressed as remote reservoir RRSV-one-way compensation valve PRV1 / 2-hydraulic cylinder shutoff valve PSV1 / 2-hydraulic cylinder HM. The other operation steps are consistent with the operation steps in FIG. 9, and the details will not be described again here.

[0076] 32 corresponds to FIG 10 and shows a schematic diagram of the pressurizing operation performed by the vehicle braking system of the fifth exemplary configuration in the first redundant braking mode, and the operation procedure is consistent with that of FIG 10. The details will not be described again here.

[0077] Figure 33 corresponds to Figure 11 and shows a schematic diagram of the pressurizing operation performed by the vehicle braking system of the fifth exemplary configuration in the second redundant braking mode, and the operation procedure is consistent with that of Figure 11. Details will not be described again here.

[0078] A method of performing vehicle braking using the vehicle braking system of the present application may include performing a braking operation by a master cylinder fluid supply brake mode, a hydraulic cylinder fluid supply brake mode, or an ESP fluid supply brake mode. The master cylinder fluid supply brake mode includes supplying pressurized brake fluid in a brake master cylinder in a DPB module to a liquid supply line of each pair of brake wheel cylinders and then to the brake wheel cylinders, and discharging the brake fluid in the brake wheel cylinders to a remote reservoir. The hydraulic cylinder fluid supply brake mode includes supplying pressurized brake fluid in a hydraulic cylinder in a DPB module to a liquid supply line of each pair of brake wheel cylinders and then to the brake wheel cylinders, and discharging the brake fluid in the brake wheel cylinders to a remote reservoir. The ESP fluid supply brake mode includes allowing the brake fluid in the remote reservoir to pass through a compensation liquid supply line, be pressurized by a pump on the compensation liquid supply line, and then be supplied to a liquid inlet end of a liquid inlet valve of the brake wheel cylinder, and discharging the brake fluid in the brake wheel cylinders to a remote reservoir. As mentioned above, the master cylinder fluid supply braking mode may be executed when the brake pedal is depressed when the vehicle is not started, or when the hydraulic cylinder or control unit in the electric machine or DPB module fails and the pump or control unit in the electric machine or ESP module fails. The hydraulic cylinder fluid supply braking mode may be executed after the vehicle is started and the braking system is not faulty. The ESP fluid supply braking mode may be executed when there is insufficient brake fluid or brake pressure in the hydraulic cylinder of the DPB module or when the DPB module fails. The vehicle braking method may further include gradually releasing the pressure in the brake wheel cylinders when the brake pedal is gradually released when the vehicle is started.The vehicle braking method may further include the steps of: adding fluid to the brake master cylinder by the master cylinder reservoir, and adding fluid to the hydraulic cylinder by the master cylinder reservoir (the first and second exemplary configurations in FIGS. 1a and 1b, the third and fourth exemplary configurations in FIGS. 12a and 12b) or the remote reservoir (the fifth and sixth exemplary configurations in FIGS. 23a and 23b) when the automatic vehicle holding function is performed; and draining the brake fluid in the fluid supply lines of each pair of brake wheel cylinders and the brake fluid in the brake wheel cylinders through the fluid drain line to the remote reservoir when the automatic vehicle holding function is terminated. The vehicle braking method may further include the steps of adding fluid to the hydraulic cylinder by the master cylinder reservoir (the first and second exemplary configurations in FIGS. 1a and 1b, the third and fourth exemplary configurations in FIGS. 12a and 12b) or the remote reservoir (the fifth and sixth exemplary configurations in FIGS. 23a and 23b) when the brake fluid in the hydraulic cylinder is insufficient.

[0079] The present application also relates to a control unit capable of carrying out the above-mentioned vehicle braking method. The control unit may be dedicated to the aforementioned vehicle braking system or may be integrated in a control unit of the vehicle engine. A vehicle braking system according to the invention may comprise the above-mentioned control unit.

[0080] Before describing in detail any embodiments of the invention, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the accompanying drawings. The invention is capable of other embodiments and of being practiced or carried out in various ways.

[0081] From the above description of specific examples provided with reference to the attached drawings, it will be clear to those skilled in the art that the systems and methods described herein constitute exemplary embodiments of the invention, but the invention contained herein is not limited to the specific examples described above. Various modifications can be made to the specific configurations without departing from the scope of the invention as defined by the following claims, all of which fall within the scope of protection of this application.

Claims

1. A vehicle braking system comprising a DPB module (100) associated with the brake pedal (B) of a vehicle and an ESP module (200) associated with the brake wheel cylinder of the vehicle, wherein the DPB module (100) comprises a brake master cylinder (MC) actuated by the brake pedal (B), a master cylinder reservoir (MRSV) having a fixed capacity and in fluid communication with the brake master cylinder, a pedal feel simulator (PFS), and a hydraulic cylinder (HM) driven by an electromechanical device, and the pedal The PFS provides a simulated circuit from the high-pressure side of the brake master cylinder to the master cylinder reservoir, and the ESP module (200) includes a remote reservoir (RRSV) and provides fluid supply lines (L1, L2) for supplying brake fluid to each pair of brake wheel cylinders of the vehicle's two pairs, fluid discharge lines (L3, L4) for discharging the brake fluid, and compensating fluid supply lines (L5, L6) connecting the fluid supply lines and the fluid discharge lines. A vehicle braking system comprising: a fluid supply line which can be selectively connected to the high-pressure side of the brake master cylinder or the high-pressure side of the hydraulic cylinder (HM) to receive pressurized brake fluid and provide it to the brake wheel cylinders; a fluid discharge line which is configured to allow the brake fluid from each of the brake wheel cylinders to be discharged to the remote reservoir; and a compensating fluid supply line which comprises pumps (P1 and P2) which each of the pumps has an inlet side and an outlet side which are in fluid communication with the fluid discharge line and the fluid supply line, respectively, so that it can draw from the fluid discharge line and provide the pressurized brake fluid to the fluid supply line.

2. The outlet side of the brake master cylinder is connected to the fluid supply line by an operable master cylinder shut-off valve, and the high-pressure side of the hydraulic cylinder is connected to the fluid supply line by an operable hydraulic cylinder shut-off valve. The vehicle braking system according to claim 1.

3. The DPB module (100) further comprises a hydraulic cylinder fluid inlet line (L21) that enables the inlet (41) of the hydraulic cylinder (HM) to be in fluid communication with the master cylinder reservoir (MRSV). The vehicle braking system according to claim 2.

4. The DPB module (100) further includes a hydraulic cylinder compensation line (L11) having one end adjacent to the outlet (42) of the hydraulic cylinder (HM) and in fluid communication with the hydraulic cylinder (HM), and the other end in fluid communication with the master cylinder reservoir (MRSV), The hydraulic cylinder compensation line (L11) includes: A one-way compensating valve (PRV) for one-way conduction from the master cylinder reservoir (MRSV) to the hydraulic cylinder (HM), or A movable hydraulic cylinder compensating valve (PIV) is positioned between the master cylinder reservoir (MRSV) and the hydraulic cylinder (HM). A will be established. The vehicle braking system according to claim 3.

5. The remote reservoir (RRSV) is in fluid communication with the inlet side of the system pressure control valves (SC1 and SC2) on the liquid supply line via a one-way compensating valve (PRV1 or PRV2). The vehicle braking system according to claim 3.

6. The remote reservoir (RRSV) is higher than the master cylinder reservoir (MRSV), the remote reservoir (RRSV) has an oil injection port, and the master cylinder reservoir (MRSV) does not have an oil injection port, or The remote reservoir (RRSV) is lower than the master cylinder reservoir (MRSV), the remote reservoir (RRSV) does not have an oil injection port, and the master cylinder reservoir (MRSV) has an oil injection port. The capacity of the remote reservoir (RRSV) of the ESP module (200) is greater than the capacity of the master cylinder reservoir (MRSV) of the DPB module (100), and The remote reservoir (RRSV) and the master cylinder reservoir (MRSV) are characterized by one or more of the following: being in fluid communication with each other by a pipeline (T), or not being in communication with each other. The vehicle braking system according to claim 1.

7. The remote reservoir (RRSV) comprises partially isolated first and second remote storage spaces connected to the fluid discharge lines of the first and second pairs of brake wheel cylinders of the vehicle, respectively, and a third remote storage space isolated from the first and second remote storage spaces at a preset height, the third remote storage space being in fluid communication with the master cylinder reservoir (MRSV) of the DPB module. The vehicle braking system according to claim 6.

8. The ESP module (200) is provided with a single fluid discharge line for all of the brake wheel cylinders, and the single fluid discharge line is in fluid communication with the third remote storage space. The vehicle braking system according to claim 7.

9. A vehicle braking method implemented using the vehicle braking system described in claim 1, The process includes performing a braking operation using a master cylinder fluid supply brake mode, a hydraulic cylinder fluid supply brake mode, or an ESP fluid supply brake mode. The master cylinder fluid supply brake mode includes supplying the pressurized brake fluid in the brake master cylinder (MC) in the DPB module to the fluid supply lines of each pair of brake wheel cylinders, and then to the brake wheel cylinders, and discharging the brake fluid in the brake wheel cylinders to the remote reservoir (RRSV), The hydraulic cylinder fluid supply brake mode includes supplying the pressurized brake fluid in the hydraulic cylinder (HM) in the DPB module to the fluid supply lines of each pair of brake wheel cylinders, and then to the brake wheel cylinders, and discharging the brake fluid in the brake wheel cylinders to the remote reservoir (RRSV), The ESP fluid supply mode enables brake fluid in the remote reservoir (RRSV) to pass through the compensating fluid supply line, be pressurized by the pump on the compensating fluid supply line, and then supplied to the fluid supply line and then to the brake wheel cylinder, and the brake fluid in the brake wheel cylinder is discharged to the remote reservoir (RRSV).

10. The master cylinder fluid supply brake mode is executed when the brake pedal is pressed while the vehicle is not running, or when the electromechanism in the DPB module (100) or the hydraulic cylinder (HM) or control unit fails, and the electromechanism in the ESP module (200) or the pump or control unit fails. The hydraulic cylinder fluid supply brake mode is performed when the braking system has not failed after the vehicle has started. The ESP fluid supply brake mode can be executed when the brake fluid or brake pressure of the hydraulic cylinder (HM) of the DPB module (100) is insufficient or when the DPB module (100) is malfunctioning. The vehicle braking method according to claim 9.

11. The following steps, namely, When the automatic vehicle holding function is performed, the process involves adding the fluid to the brake master cylinder by the master cylinder reservoir. When the automatic vehicle holding function is executed or when the brake fluid in the hydraulic cylinder becomes insufficient, the process of adding the fluid to the hydraulic cylinder by the master cylinder reservoir or the remote reservoir, and An exhaust process that, when the automatic vehicle holding function is terminated, enables the discharge of brake fluid from the fluid supply lines of each pair of brake wheel cylinders and the brake fluid from each brake wheel cylinder to the remote reservoir via the fluid discharge line. Including one or more of the following: The vehicle braking method according to claim 10.

12. The process further includes gradually releasing the pressure in the brake wheel cylinder after the vehicle has started and the brake pedal has been gradually released, The vehicle braking method according to claim 11.

13. A control unit for a vehicle braking system configured to implement the vehicle braking method described in claim 9.

14. A vehicle braking system comprising the control unit described in claim 13.

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