A brake-by-wire hydraulic brake system

Abstract

The utility model discloses a kind of drive-by-wire hydraulic braking systems, including at least two independent brake modules, one brake module is as main brake module, is connected with pedal, and the braking intention of driver can be obtained;The remaining brake modules are connected with the main brake module by CAN, and pedal signal is synchronously obtained;Each brake module includes hydraulic control unit and electronic control unit.The drive-by-wire hydraulic braking system and its control method are reasonable in design, simultaneously carry two sets and above brake modules, and can be triggered by same pedal input signal, and corresponding caliper is synchronously or independently pressurized to supply liquid, braking response is obviously improved, and the braking demand of large-tonnage vehicle can be met;While the ECU of each brake module can integrate EPB controller, realize the control redundancy of vehicle EPB caliper, and improve the safety of vehicle.

Description

Technical Field

[0001] This utility model relates to the field of automotive braking technology, and in particular to a drive-by-wire hydraulic braking system. Background Technology

[0002] With the development of hydraulic brake-by-wire technology and the automotive industry's demands for intelligence and automation, the application of brake-by-wire technology has been greatly expanded. However, for heavy-duty vehicles, due to the large diameter of their brake caliper cylinders, the required hydraulic fluid volume far exceeds that of ordinary passenger cars. Common hydraulic brake-by-wire systems are mainly developed for light passenger vehicles, and their limited fluid supply capacity makes them unsuitable for direct application in heavy-duty vehicles to meet braking regulations.

[0003] For example, Chinese patent CN112389401 discloses an electro-hydraulic braking system, which includes an oil tank, a first cylinder, a second cylinder, a drive unit, an inlet valve, a wheel cylinder, a first hydraulic circuit, a first isolation valve, a second hydraulic circuit, and an outlet valve. The drive unit drives the first piston of the second cylinder to move. The wheel cylinder is connected to the inlet valve. The first hydraulic circuit is located between the first cylinder and the inlet valve. The first isolation valve is located on the first hydraulic circuit. The second hydraulic circuit is located between the second cylinder and the inlet valve. The second hydraulic circuit is equipped with a forward control valve and a reverse control valve. The outlet valve is connected between the wheel cylinder and the oil tank. The braking module is a single unit, which cannot meet the braking requirements of large-tonnage vehicles. Utility Model Content

[0004] To address the shortcomings of existing technologies, this utility model provides a drive-by-wire hydraulic braking system to meet the braking requirements of heavy-duty vehicles.

[0005] To solve the above-mentioned technical problems, the technical solution adopted by this utility model is as follows:

[0006] A drive-by-wire hydraulic braking system includes at least two independent braking modules, one of which serves as the main braking module and is connected to the pedal to acquire the driver's braking intention; the remaining braking modules are connected to the main braking module via CAN and synchronously acquire pedal signals; each braking module includes a hydraulic control unit and an electronic control unit.

[0007] Further or preferred:

[0008] The braking module is connected to the vehicle's hydraulic brake calipers to perform hydraulic braking on the entire vehicle; and / or the corresponding electronic parking brake (EPB) caliper controller is integrated into the ECU of each braking module to achieve control redundancy of the vehicle's EPB calipers.

[0009] The hydraulic control unit includes a reservoir, a decoupling and isolation solenoid valve, a booster structure, a pressure supply solenoid valve, and a wheel-end valve group hydraulic circuit; and / or the hydraulic braking unit of the main braking module additionally includes a detection solenoid valve, a master cylinder, a stroke sensor, a pedal valve, and a pedal feel simulator.

[0010] The reservoir has one outlet, which is connected to the hydraulic circuit of the wheel-end valve group via a decoupling solenoid valve, to the outlet of the booster cylinder via an inlet check valve, and to the pressure relief valve of the wheel-end valve group hydraulic circuit. Alternatively, the reservoir of the main brake module has two outlets. One outlet is connected to the hydraulic circuit of the wheel-end valve group via a detection solenoid valve, the master cylinder, and the decoupling solenoid valve, and is also connected to the pressure relief valve in the wheel-end valve group hydraulic circuit. The other outlet is connected to the outlet of the booster cylinder via an inlet check valve.

[0011] The pressurization structure is connected to the hydraulic oil circuit of the wheel end valve group via a pressure supply solenoid valve.

[0012] The booster structure includes a brushless motor, a transmission mechanism, and a booster cylinder.

[0013] The main braking module has a detection solenoid valve connected between its reservoir outlet and the master cylinder for assisting in detecting leaks in the braking circuit.

[0014] A pressure sensor is provided in the oil circuit between the booster structure and the pressure supply solenoid valve; or an additional pressure sensor is provided between the master cylinder of the main braking module and the decoupling isolation solenoid valve to measure the pressure value of the corresponding oil circuit.

[0015] The hydraulic circuit of the wheel-end valve group includes two circuits, each equipped with a pressure boosting solenoid valve and a pressure relief solenoid valve; the outlet end of the pressure boosting solenoid valve is connected to the inlet end of the pressure relief solenoid valve and the hydraulic clamp; the outlet end of the pressure relief solenoid valve is connected to one of the oil circuit outlets of the liquid storage tank.

[0016] Compared with the prior art, this utility model has the following advantages:

[0017] This drive-by-wire hydraulic braking system is rationally designed, equipped with two or more braking modules, and can be triggered by the same pedal input signal to synchronously or independently pressurize and supply fluid to the corresponding calipers, significantly improving braking response and meeting the braking requirements of heavy-duty vehicles. At the same time, the ECU of each braking module can be integrated with an EPB controller to achieve redundant control of the vehicle's EPB calipers, improving vehicle safety. Attached Figure Description

[0018] The following is a brief explanation of the contents of each of the accompanying drawings and the markings in the drawings:

[0019] Figure 1This is a schematic diagram of the braking system of this utility model.

[0020] In the picture:

[0021] 1-Reservoir I, 2-Detection Solenoid Valve, 3-Brake Pedal, 4-Stroke Sensor, 5-Master Cylinder, 6-Pedal Valve, 7-Pedal Sensing Simulator, 8-Pressure Sensor I, 9-Decoupling Isolation Solenoid Valve I, 10-Pressure Supply Solenoid Valve I, 11-Pressure Sensor II, 12-Inlet Check Valve I, 13-Boost Cylinder I, 14-Transmission Mechanism I, 15-Brushless Motor I, 16-Boost Solenoid Valve I, 17-Relief Solenoid Valve I, 18-Boost Solenoid Valve II, 19-Relief Solenoid Valve II, 20-ECU 1;

[0022] 21-Reservoir II, 22-Decoupling and isolation solenoid valve II, 23-Pressure supply solenoid valve II, 24-Pressure sensor III, 25-Inlet check valve II, 26-Boost cylinder II, 27-Transmission mechanism II, 27-Brushless motor II, 29-Boost solenoid valve III, 30-Relief solenoid valve III, 31-Boost solenoid valve IV, 32-Relief solenoid valve IV, 33-ECU 2. Detailed Implementation

[0023] The specific embodiments of this utility model will be further described in detail below with reference to the accompanying drawings and through the description of the examples.

[0024] like Figure 1 As shown, the drive-by-wire hydraulic braking system is equipped with at least two independent braking modules; one of the braking modules serves as the main braking module, is connected to the pedal-3, and is equipped with a stroke sensor-4 to acquire the braking signal of the pedal; each braking module includes a hydraulic control unit (HCU) and an electronic control unit (ECU).

[0025] The ECU1-20 of the main braking module is electrically connected to the stroke sensor-4. After acquiring the braking signal, it can immediately send the signal to the ECUs of other braking modules via CAN, such as ECU 2-33 in this example.

[0026] Each braking module's ECU can integrate an EPB controller, enabling redundant control of the vehicle's EPB calipers and improving vehicle safety.

[0027] The HCU includes reservoirs I-1 & II-21, decoupling and isolation solenoid valves I-9 & II-22, a pressurization structure, and pressure supply solenoid valves I-10 & II-23. The pressurization structure is connected to the hydraulic circuit of the wheel-end valve assembly via pressure supply solenoid valves I-10 & II-23. As an exception, the hydraulic braking unit of the main braking module additionally includes a detection solenoid valve-2, a master cylinder-5, a stroke sensor-4, a pedal valve-6, and a pedal feel simulator-7.

[0028] The reservoir II-21 has one outlet, which is connected to the wheel-end valve assembly hydraulic circuit via decoupling solenoid valve II-22; ② to the pressure relief solenoid valves III-30 and IV-32 of the wheel-end valve assembly; and ③ to the outlet of the booster cylinder II-26 via inlet check valve II-25. As an exception, the main brake module's reservoir I-1 has two outlets. One outlet is connected to the wheel-end valve assembly hydraulic circuit via detection solenoid valve-2, master cylinder-5, and decoupling solenoid valve I-9, and is also connected to the pressure relief solenoid valves I-17 and II-19 in the wheel-end valve assembly. The other outlet is connected to the outlet of the booster cylinder I-13 via inlet check valve I-12.

[0029] Brake pedal-3, stroke sensor-4 and master cylinder-5 are set up accordingly. The oil outlet of the master cylinder is connected to pedal valve-6 and pedal feel simulator-7. The pedal feel simulator-7 provides the driver with pedal damping feel.

[0030] Furthermore, the booster structure includes a brushless motor I-15 & II-28, a transmission mechanism I-14 & II-27, and a booster cylinder I-13 & II-26. The outlet of the booster cylinder I-13 & II-26 is connected to the outlet of the hydraulic oil circuit of the wheel end valve group through a pressure supply solenoid valve I-10 & II-23. The reservoir I-1 & II-21 is connected to the outlet of the corresponding booster cylinder through a liquid inlet check valve I-12 & II-25. The brushless motor I-15 & II-28 drives the transmission mechanism I-14 & II-27 to push the piston in the booster cylinder I-13 & II-26 to pressurize the brake fluid.

[0031] Furthermore, the outlet of the reservoir I-1 is connected to a detection solenoid valve-2 for auxiliary detection of brake circuit leaks. A pressure sensor I-8 is installed in the oil circuit between the master cylinder-5 and the decoupling isolation solenoid valve I-9. Pressure sensors II-11 and III-24 are installed in the oil circuit between the booster structure and the pressure supply solenoid valves I-10 & II-23.

[0032] Furthermore, the hydraulic circuit of the wheel-end valve assembly includes two loops, each equipped with one pressure-boosting solenoid valve and one pressure-relief solenoid valve. The outlet of the pressure-boosting solenoid valves I-16, II-18, III-29, and IV-31 is connected to the inlet of the pressure-relief solenoid valves I-17, II-19, III-30, and IV-32 and the hydraulic clamp. The outlet of the pressure-relief solenoid valves I-17, II-19, III-30, and IV-32 is connected to one of the oil circuit outlets of the reservoirs I-1 and II-21.

[0033] The braking control method of the steerable hydraulic braking system of this utility model includes the following steps:

[0034] When the driver needs to brake, the brake pedal-3 is pressed. After the travel sensor-4 obtains the braking signal, it is transmitted to the ECU1-20 of the main braking module. The ECU immediately transmits the braking signal to other ECUs via CAN, such as ECU2-33 in this example.

[0035] Each ECU controls the solenoid valve and booster structure of its corresponding HCU, enabling a single pedal input signal to synchronously control the operation of multiple braking modules.

[0036] Under normal operating conditions, the master cylinder brake fluid does not directly participate in wheel-end braking, but is instead pumped into the pedal feel simulator to provide the driver with pedal damping feel;

[0037] Each braking module synchronously pressurizes and supplies fluid to its corresponding caliper, greatly improving braking response speed. Simultaneously, the ECU of each braking module can integrate an EPB controller, achieving redundancy in the control of the vehicle's EPB calipers and enhancing vehicle safety.

[0038] The preferred embodiment of this utility model is as follows:

[0039] like Figure 1 As shown, the drive-by-wire hydraulic braking system includes at least two independent braking modules. One braking module serves as the main braking module, connected to pedal-3, and can acquire the driver's braking intention. The remaining braking modules can be connected to the main braking module via CAN to synchronously acquire pedal signals. Each braking module includes a hydraulic control unit (HCU) and an electronic control unit (ECU).

[0040] The main braking module includes 1-reservoir I, 2-detection solenoid valve, 3-brake pedal, 4-stroke sensor, 5-master cylinder, 6-pedal valve, 7-pedal feel simulator, 8-pressure sensor I, 9-decoupling isolation solenoid valve I, 10-pressure supply solenoid valve I, 11-pressure sensor II, 12-inlet check valve I, 13-boost cylinder I, 14-transmission mechanism I, 15-brushless motor I, 16-boost solenoid valve I, 17-pressure relief solenoid valve I, 18-boost solenoid valve II, 19-pressure relief solenoid valve II, 20-ECU 1.

[0041] Another braking module includes 21-reservoir II, 22-decoupling isolation solenoid valve II, 23-pressure supply solenoid valve II, 24-pressure sensor III, 25-inlet check valve II, 26-boost cylinder II, 27-transmission mechanism II, 27-brushless motor II, 29-boost solenoid valve III, 30-pressure relief solenoid valve III, 31-boost solenoid valve IV, 32-pressure relief solenoid valve IV, and 33-ECU 2.

[0042] The main braking module contains two pressure generating structures. The first pressure generating structure is achieved by a master cylinder-5 with a single-loop output. When the driver depresses the brake pedal-3, the displacement sensor-4 transmits the pedal displacement signal to the ECU 1-20, triggering the brake-by-wire function. The ECU 1-20 opens the pedal valve-6, and the piston in the master cylinder-5 compresses the brake fluid within the cylinder. The brake fluid, after passing through the pedal valve-6, is forced into the pedal feel simulator-7, providing the driver with pedal damping feedback. As a special case, when the ECU 1-20 of the main braking module fails, the pedal valve-6 and the pressure supply solenoid valve I-10 are closed, while the decoupling isolation solenoid valve I-9 is open. The brake fluid, compressed by the piston in the master cylinder-5, passes through the decoupling isolation solenoid valve I-9 and the wheel-end hydraulic valve assembly circuit, entering the wheel-end calipers for hydraulic braking.

[0043] The second pressure-generating structure, after triggering the brake-by-wire function, opens the pressure supply solenoid valve I-10, closes the decoupling isolation solenoid valve I-9, and activates the brushless motor I-15, driving the transmission mechanism I-14. This drives the piston in the booster cylinder I-13 to compress the brake fluid in the cylinder. The compressed brake fluid then passes through the wheel-end hydraulic valve assembly circuit and enters the wheel-end caliper for hydraulic braking. Each wheel-end hydraulic valve assembly circuit contains two loops, each equipped with one booster solenoid valve and one pressure relief solenoid valve.

[0044] The remaining braking modules only contain a second pressure generating structure. That is, after triggering the brake-by-wire function, the pressure supply solenoid valve II-23 is in the connected state, the decoupling isolation solenoid valve II-22 is in the closed state, the brushless motor II-28 is turned on, driving the transmission mechanism II-27, which in turn drives the piston in the booster cylinder II-26 to compress the brake fluid in the cylinder. The compressed brake fluid then enters the wheel-end hydraulic valve assembly circuit to perform hydraulic braking. Each wheel-end hydraulic valve assembly circuit contains two loops, each equipped with one booster solenoid valve and one pressure relief solenoid valve.

[0045] ECU 1 and ECU 2 can communicate in real time via CAN to transmit braking signals.

[0046] One of the outlets of the main brake module reservoir I-1 is connected to the master cylinder-5 by a detection solenoid valve-2, which is used to assist in detecting brake circuit leakage.

[0047] When brake pedal-3 is depressed, stroke sensor-4 receives the braking signal and transmits it to ECU 1-20. ECU 1-20 then immediately transmits the braking signal to ECU 2-33 via CAN. ECU 1 and ECU 2 respectively control the decoupling isolation solenoid valve I-9 and decoupling isolation solenoid valve II-22 to close, and the pressure supply solenoid valve I-10 and pressure supply solenoid valve II-23 to open.

[0048] The pedal valve-6 of the main brake module will be opened, and the piston in the master cylinder-5 will compress the brake fluid in the cylinder as the driver presses the brake pedal-3. The brake fluid will then enter the pedal feel simulator-7 through the pedal valve-6 to provide the driver with pedal damping feel.

[0049] The system can activate the brake-by-wire function of some or all of the braking modules according to the vehicle's braking needs; each braking module supplies fluid to the two wheel-end calipers, which can meet the fluid requirements of heavy-duty vehicles.

[0050] This utility model's drive-by-wire hydraulic braking system utilizes at least two braking modules on heavy-duty vehicles. These two modules can be triggered by a single pedal input signal, synchronously supplying hydraulic fluid to the calipers. Compared to the traditional braking method where a single braking module supplies fluid to four calipers, this utility model significantly improves the fluid supply capacity, meeting the braking requirements of heavy-duty vehicles. Furthermore, corresponding electronic parking brake (EPB) caliper controllers can be integrated into the ECU of each module, achieving control redundancy for the vehicle's EPB calipers and enhancing vehicle safety.

[0051] The above description is only a preferred embodiment of the present utility model. The above technical features can be arbitrarily combined to form multiple embodiments of the present utility model.

[0052] The present invention has been described above with reference to the accompanying drawings. Obviously, the specific implementation of the present invention is not limited to the above-described manner. Any non-substantial improvements made using the concept and technical solution of the present invention, or the direct application of the concept and technical solution of the present invention to other occasions without modification, are all within the protection scope of the present invention.

Claims

1. A drive-by-wire hydraulic braking system, comprising at least two independent braking modules, characterized in that: One of the braking modules serves as the main braking module, connected to the pedal, and can acquire the driver's braking intention; the remaining braking modules are connected to the main braking module via CAN to synchronously acquire pedal signals; each braking module includes a hydraulic control unit and an electronic control unit.

2. The drive-by-wire hydraulic braking system as described in claim 1, characterized in that: The braking module is connected to the vehicle's hydraulic brake calipers to perform hydraulic braking on the entire vehicle; and / or the corresponding electronic parking brake (EPB) caliper controller is integrated into the ECU of each braking module to achieve control redundancy of the vehicle's EPB calipers.

3. The drive-by-wire hydraulic braking system as described in claim 1, characterized in that: The hydraulic control unit includes a reservoir, a decoupling and isolation solenoid valve, a booster structure, a pressure supply solenoid valve, and a wheel-end valve group hydraulic circuit; and / or the hydraulic braking unit of the main braking module additionally includes a detection solenoid valve, a master cylinder, a stroke sensor, a pedal valve, and a pedal feel simulator.

4. The drive-by-wire hydraulic braking system as described in claim 3, characterized in that: The reservoir has one outlet, which is connected to the hydraulic circuit of the wheel-end valve group via a decoupling solenoid valve, to the outlet of the booster cylinder via an inlet check valve, and to the pressure relief valve of the wheel-end valve group hydraulic circuit. Alternatively, the reservoir of the main brake module has two outlets. One outlet is connected to the hydraulic circuit of the wheel-end valve group via a detection solenoid valve, the master cylinder, and the decoupling solenoid valve, and is also connected to the pressure relief valve in the wheel-end valve group hydraulic circuit. The other outlet is connected to the outlet of the booster cylinder via an inlet check valve.

5. The drive-by-wire hydraulic braking system as described in claim 3, characterized in that: The pressurization structure is connected to the hydraulic oil circuit of the wheel end valve group via a pressure supply solenoid valve.

6. The drive-by-wire hydraulic braking system as described in claim 3, characterized in that: The booster structure includes a brushless motor, a transmission mechanism, and a booster cylinder.

7. The drive-by-wire hydraulic braking system as described in claim 3, characterized in that: The main braking module has a detection solenoid valve connected between its reservoir outlet and the master cylinder for assisting in detecting leaks in the braking circuit.

8. The drive-by-wire hydraulic braking system as described in claim 3, characterized in that: A pressure sensor is provided in the oil circuit between the booster structure and the pressure supply solenoid valve; or an additional pressure sensor is provided between the master cylinder of the main braking module and the decoupling isolation solenoid valve to measure the pressure value of the corresponding oil circuit.

9. The drive-by-wire hydraulic braking system as described in claim 3, characterized in that: The hydraulic circuit of the wheel-end valve group includes two circuits, each equipped with a pressure boosting solenoid valve and a pressure relief solenoid valve; the outlet end of the pressure boosting solenoid valve is connected to the inlet end of the pressure relief solenoid valve and the hydraulic clamp; the outlet end of the pressure relief solenoid valve is connected to one of the oil circuit outlets of the liquid storage tank.

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