Electronic hydraulic braking system and vehicle

Abstract

The embodiment of the invention provides an electronic hydraulic braking system and a vehicle, and relates to the technical field of braking systems. The electronic hydraulic braking system comprises an electronic stability control system, an oil can module, a first main cylinder module and a second main cylinder module. The first main cylinder module and the second main cylinder module are respectively provided with a motor; the oil can module is connected with the first main cylinder module and the second main cylinder module. The first main cylinder module and the second main cylinder module are both connected to the electronic stability control system. Compared with a traditional braking mode of a single-main-cylinder braking system, the power assisting capacity of the electronic hydraulic braking system is remarkably improved.

Description

Technical Field

[0001] The present application relates to the technical field of braking systems, and particularly to an electronic hydraulic braking system and a vehicle. Background Art

[0002] An electronic hydraulic brake (EHB) is developed on the basis of a traditional hydraulic brake. The operating mechanism replaces the traditional hydraulic brake pedal with an electronic brake pedal and eliminates the large-volume vacuum booster.

[0003] For commercial vehicles with a load greater than 6 tons, the boosting ability may be insufficient when using the existing electronic hydraulic braking system.

[0004] How to improve the boosting ability of the electronic hydraulic braking system is a technical problem to be solved in the present application. Summary of the Invention

[0005] The purpose of the present application is to provide an electronic hydraulic braking system and a vehicle to solve the technical problem of how to improve the boosting ability of the electronic hydraulic braking system in the prior art.

[0006] To achieve the above purpose, the embodiments of the present application adopt the following technical solutions.

[0007] In a first aspect, an embodiment of the present application provides an electronic hydraulic braking system, including an electronic stability control system, an oil pot module, a first master cylinder module, and a second master cylinder module; both the first master cylinder module and the second master cylinder module have motors. The oil pot module is respectively connected to the first master cylinder module and the second master cylinder module; the oil pot module is used to provide brake fluid for the first master cylinder module and the second master cylinder module. Both the first master cylinder module and the second master cylinder module are connected to the electronic stability control system.

[0008] Optionally, the electronic stability control system includes a first oil circuit and a second oil circuit. The first oil circuit is used to provide braking for the left wheels, and the second oil circuit is used to provide braking for the right wheels; or the first oil circuit is used to provide braking for the right wheels, and the second oil circuit is used to provide braking for the left wheels; or the first oil circuit is used to provide braking for the front axle, and the second oil circuit is used to provide braking for the rear axle; or the first oil circuit is used to provide braking for the rear axle, and the second oil circuit is used to provide braking for the front axle. The output of the first master cylinder module includes two paths, and the output of the second master cylinder module includes two paths. The electronic hydraulic braking system further includes a first valve and a second valve. The first output path of the first master cylinder module is directly connected to the first oil circuit; The second output path of the first master cylinder module is connected to the second oil circuit through the first valve; The first output path of the second master cylinder module is connected to the first oil circuit through the second valve; The second output path of the second master cylinder module is directly connected to the second oil circuit.

[0009] Optionally, the braking force provided by the electronic hydraulic braking system for the rear axle and the braking force provided for the front axle increase as the braking demand increases. When the braking demand continues to increase after reaching the set demand threshold, the increase in the braking force provided for the rear axle is less than the increase in the braking force provided for the front axle.

[0010] Optionally, the first master cylinder module includes a pedal displacement sensor, a first motor module, and a first master cylinder; the electronic hydraulic braking system further includes a first valve; According to the output signal of the pedal displacement sensor, the first motor module pressurizes the brake fluid in the first master cylinder; The first output path of the first master cylinder is directly connected to the electronic stability control system; The second output path of the first master cylinder is connected to the electronic stability control system through the first valve.

[0011] Optionally, the second master cylinder module includes a second motor module and a second master cylinder; the electronic hydraulic braking system further includes a second valve; According to the output signal of the first master cylinder module, the second motor module pressurizes the brake fluid in the second master cylinder; The first output path of the second master cylinder is connected to the electronic stability control system through the second valve; The second output path of the second master cylinder is directly connected to the electronic stability control system.

[0012] Optionally, both the second master cylinder module and the first master cylinder module are connected to the CAN bus, and the second motor module pressurizes the brake fluid in the second master cylinder according to the signal output by the first master cylinder module to the CAN bus.

[0013] Optionally, when both the first master cylinder module and the second master cylinder module are working properly, the first master cylinder module and the second master cylinder module jointly pressurize the front and rear axles; In the case of failure of the first master cylinder module, the second master cylinder module takes over the pressurization of the front and rear axles; In the case of failure of the second master cylinder module, the first master cylinder module takes over the pressurization of the front and rear axles.

[0014] Optionally, when both the first master cylinder module and the second master cylinder module are operating normally, the first master cylinder module and the second master cylinder module distribute the braking pressure according to a preset ratio.

[0015] Optionally, the electronic stability control system includes a return pump. When the electronic stability control system detects that the following conditions are all satisfied, it controls the return pump to move to adjust the pressure to the anti-lock braking system trigger level: The hydraulic pressure of the first master cylinder module or the second master cylinder module reaches a high pressure threshold; The displacement detected by the pedal displacement sensor exceeds the displacement threshold; The vehicle speed exceeds the vehicle speed threshold.

[0016] In a second aspect, an embodiment of the present application provides a vehicle, and the vehicle includes the electronic hydraulic braking system described in the first aspect.

[0017] Compared with the prior art, the present application has the following beneficial effects: The electronic hydraulic braking system provided by the embodiment of the present application includes at least two master cylinder modules, namely a first master cylinder module and a second master cylinder module. Both master cylinder modules are assisted by motors to increase the hydraulic pressure. Compared with the braking method of the traditional single master cylinder braking system, the boosting ability of the electronic hydraulic braking system is significantly improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings required in the embodiments. It should be understood that the following drawings only show some embodiments of the present application, and therefore should not be regarded as limiting the scope. For those of ordinary skill in the art, other related drawings can be obtained based on these drawings without creative efforts.

[0019] Figure 1 A schematic diagram of an electronic hydraulic braking system provided by an embodiment of the present application; Figure 2 A schematic diagram of an electronic hydraulic braking system including a first valve and a second valve provided by an embodiment of the present application; Figure 3 A schematic diagram of communication between a first master cylinder module and a second master cylinder module provided by an embodiment of the present application; Figure 4 A schematic diagram of a specific implementation manner of an electronic stability control system 1 provided by an embodiment of the present application. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0020] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of this application. The described embodiments are some, but not all, of the embodiments of this application. The components of the embodiments of this application described herein are usually arranged and designed in various different configurations.

[0021] Therefore, the detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely represents selected embodiments of this application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in this application without creative efforts belong to the scope of protection of this application. Without conflict, the following embodiments and the features in the embodiments may be combined with each other.

[0022] In the description of this application, it should be noted that: Relative terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations; "Connection" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected, or indirectly connected through an intermediate medium.

[0023] The electronic hydraulic braking system can be applied to various vehicles, such as Figure 1 , the electronic hydraulic braking system includes an electronic stability control system (Electronic Stability Control, abbreviated as ESC), an oil pot module, a first master cylinder module, and a second master cylinder module; both the first master cylinder module and the second master cylinder module have motors. The electronic stability control system is used to brake each wheel of the vehicle through the hydraulic pressure of the brake fluid. Especially when the vehicle experiences side slip, fishtailing, or understeer / oversteer, the electronic stability control system can automatically intervene, brake single or multiple wheels, and adjust the engine power output to help the vehicle regain stability. The oil pot module is used to provide brake fluid for the first master cylinder module and the second master cylinder module. The brake fluid can be selected as the oil suitable for the hydraulic system.

[0024] There are the following connection relationships among the electronic stability control system, the oil pot module, the first master cylinder module, and the second master cylinder module: The oil pot module is respectively connected to the first master cylinder module and the second master cylinder module; Both the first master cylinder module and the second master cylinder module are connected to the electronic stability control system.

[0025] Compared with the braking method of the traditional single master cylinder braking system, the beneficial effects of this electronic hydraulic braking system are as follows: Since the electronic hydraulic braking system has at least two master cylinder modules, namely the first master cylinder module and the second master cylinder module, to provide hydraulic pressure, the boosting ability of the electronic hydraulic braking system is significantly improved compared with the braking method of the traditional single master cylinder braking system.

[0026] Such as Figure 2 , the electronic stability control system may include a first oil circuit and a second oil circuit. Different oil circuits provide hydraulic pressure for different wheel brake pads. For example, the following different embodiments: The first oil circuit is used to provide braking for the left wheels, and the second oil circuit is used to provide braking for the right wheels; Or the first oil circuit is used to provide braking for the right wheels, and the second oil circuit is used to provide braking for the left wheels; Or the first oil circuit is used to provide braking for the front axle, and the second oil circuit is used to provide braking for the rear axle; Or the first oil circuit is used to provide braking for the rear axle, and the second oil circuit is used to provide braking for the front axle.

[0027] The beneficial effect of the method of dividing into left and right sides is that when the vehicle experiences sideslip, fishtailing, or understeer / oversteer, the electronic stability control system can more quickly provide different hydraulic pressures for the left and right wheel brake pads, so as to better stabilize the vehicle when experiencing sideslip, fishtailing, or understeer / oversteer.

[0028] Each master cylinder module can be simultaneously connected to the first oil circuit and the second oil circuit of the electronic stability control system. The output of the first master cylinder module includes two paths, and the output of the second master cylinder module includes two paths. There are the following connection relationships: The first path output of the first master cylinder module is connected to the first oil circuit; The second path output of the first master cylinder module is connected to the second oil circuit; The first path output of the second master cylinder module is connected to the first oil circuit; The second path output of the second master cylinder module is connected to the second oil circuit.

[0029] In some embodiments, valves can also be provided between the output of the master cylinder module and the oil circuit of the electronic stability control system, so as to facilitate the control of the operation of different master cylinder modules. For example Figure 2 , provide a first valve and a second valve: The first path output of the first master cylinder module is directly connected to the first oil circuit; The second path output of the first master cylinder module is connected to the second oil circuit through the first valve; The first path output of the second master cylinder module is connected to the first oil circuit through the second valve; The second path output of the second master cylinder module is directly connected to the second oil circuit.

[0030] Each master cylinder module is connected separately to one path. When a certain master cylinder module fails, half of the braking force will be lost. By setting an electromagnetic valve control switch on one of the paths, both master cylinders can be capable of controlling all braking circuits, improving safety. At the same time, by only opening one valve, when there is a leak in a certain wheel-end pipeline, there will be another pipeline for braking.

[0031] If it is designed that there are valves on all 4 paths, this effect can also be achieved, but the cost is relatively high.

[0032] The two master cylinder modules can have different configurations. For example: the first master cylinder module is set to include a pedal displacement sensor, a first motor module, and a first master cylinder. The pedal displacement sensor is used to detect the displacement when the brake pedal is depressed. The second master cylinder module includes a second motor module and a second master cylinder, and the second master cylinder module has nothing to do with the brake pedal. In the first master cylinder module, according to the output signal of the pedal displacement sensor, the first motor module builds pressure of the brake fluid in the first master cylinder.

[0033] The output of the first master cylinder can be divided into two paths. The two paths of output of the first master cylinder can correspond to the first path output and the second path output of the above-mentioned first master cylinder module: the first path output of the first master cylinder is directly connected to the electronic stability control system; the second path output of the first master cylinder is connected to the electronic stability control system through a first valve.

[0034] The first master cylinder module can output a signal. The controller for the output signal can be set in the first motor module. The second master cylinder module can determine the amount of assistance according to the output signal of the first master cylinder module, that is: according to the output signal of the first master cylinder module, the second motor module builds pressure of the brake fluid in the second master cylinder.

[0035] The output of the second master cylinder can be divided into two paths. The two paths of output of the second master cylinder can correspond to the first path output and the second path output of the above-mentioned second master cylinder module: the first path output of the second master cylinder is connected to the electronic stability control system through a second valve; the second path output of the second master cylinder is directly connected to the electronic stability control system. The above composition and connection structure are as Figure 3 .

[0036] The way for the first master cylinder module to output a signal can be through a bus, such as a CAN bus. The way for the second master cylinder module to receive the output signal of the first master cylinder module can also be through a bus, that is, both the second master cylinder module and the first master cylinder module are connected to the CAN bus. The second motor module builds pressure of the brake fluid in the second master cylinder according to the signal output by the first master cylinder module to the CAN bus.

[0037] Regarding the control methods of the electronic hydraulic braking system, the first master cylinder module, and the second master cylinder module, there are multiple implementation methods, which are introduced by way of example below.

[0038] Figure 4 Shows an embodiment of an electronic stability control system 1 with multiple valves. In the figure, M represents the motor. The motor in the electronic stability control system 1 can drive two return pumps, and the return pumps can return the oil to the oil pot module to release the brakes. The oil pot module can include a large oil pot and two small oil pots; the large oil pot is respectively connected to the two small oil pots, the first small oil pot is connected to the first master cylinder module; the second small oil pot is connected to the second master cylinder module, which is convenient for the layout and oil use of the two master cylinder modules.

[0039] The electronic stability control system can be configured with the following control method: When it is detected that all the following conditions are met, control the return pump to move to adjust the pressure to the anti-lock braking system trigger level: The hydraulic pressure of the first master cylinder module or the second master cylinder module reaches the high pressure threshold; The displacement detected by the pedal displacement sensor exceeds the displacement threshold; The vehicle speed exceeds the vehicle speed threshold.

[0040] That is, during normal driving, the vehicle speed exceeds the vehicle speed threshold. In the case of emergency braking, the driver quickly steps on the brake pedal. When the displacement detected by the pedal displacement sensor exceeds the displacement threshold, the hydraulic pressure of the first master cylinder module or the second master cylinder module will also increase to reach the high pressure threshold. At this time, the electronic hydraulic braking system also participates in the work of assisting braking. In the emergency braking scenario, the driver's physical feeling is poor. This electronic hydraulic braking system can reasonably distribute the braking force through control, and finally improve the braking feeling and optimize the driving experience, etc.

[0041] Subsequently, when any of the following conditions is met, the electronic hydraulic braking system can be made to exit the work of assisting braking: The vehicle speed is lower than the exit threshold; The pedal displacement sensor reaches the release displacement threshold, that is, the driver releases the brake pedal; The hydraulic pressure of the first master cylinder module or the second master cylinder module drops to the low pressure threshold, that is, the master cylinder hydraulic pressure drops significantly.

[0042] During the process of the braking demand increasing from zero, the rear axle is often more likely to lock than the front axle, and the front axle can provide greater braking force. Therefore, the electronic hydraulic braking system can be configured as follows: The braking force provided for the rear axle and the braking force provided for the front axle increase as the braking demand increases. When the braking demand continues to increase after reaching the set demand threshold, the increase in the braking force provided for the rear axle is less than the increase in the braking force provided for the front axle, that is, the front axle braking is preferentially used. Different hydraulic pressures can be distributed, or different brake pads can be designed for the front and rear axles.

[0043] Such as Figure 4, in the figure, 1F and 2F represent the left and right wheels of the front axle, and 1R and 2R represent the left and right wheels of the rear axle. The left and right wheels of the front axle can be configured with brake pads of larger size and rougher surface, and the left and right wheels of the rear axle can be configured with smaller and slightly smoother brake pads. Thus, under the same hydraulic pressure, the front axle has stronger and more effective braking ability, that is, the increase in braking force provided for the rear axle is less than the increase in braking force provided for the front axle, that is, the front axle braking is preferentially used.

[0044] Regarding the control methods of the first master cylinder module and the second master cylinder module, they can work together: When both the first master cylinder module and the second master cylinder module are working properly, the first master cylinder module and the second master cylinder module jointly build pressure for the front and rear axles; they can adopt the same power and each undertake half of the pressure building work.

[0045] Regarding the control methods of the first master cylinder module and the second master cylinder module, they can also form a complementary relationship: When both the first master cylinder module and the second master cylinder module are working properly, the first master cylinder module and the second master cylinder module distribute the braking pressure according to a preset ratio.

[0046] Regarding the control methods of the first master cylinder module and the second master cylinder module, it can also be set that in case of a failure, one can be replaced by the other: In the case of the failure of the first master cylinder module, the second master cylinder module takes over the pressure building for the front and rear axles; In the case of the failure of the second master cylinder module, the first master cylinder module takes over the pressure building for the front and rear axles.

[0047] Regarding the control methods of the first master cylinder module and the second master cylinder module, they can also work alternately. When one is working, the other does not output power and remains in a self-locking or valve-disconnected state. This implementation method can avoid uneven aging of the first master cylinder module and the second master cylinder module, resulting in a more serious performance decay of one of them. For example: (1) One of the first master cylinder module and the second master cylinder module can be selected in turn by the number of times to provide boost pressure building. For example, first, the first master cylinder module executes a boost, and then the second master cylinder module executes a boost; (2) One of the first master cylinder module and the second master cylinder module can be selected in turn by time to provide boost pressure building for the front axle oil circuit and the rear axle oil circuit. For example, after the cumulative working duration of the first master cylinder module reaches a set duration threshold, it switches to the second master cylinder module. After the cumulative working duration of the second master cylinder module reaches a set duration threshold, it switches to the first master cylinder module, and so on in a cycle; or it switches according to the cumulative driving duration of the vehicle, that is, it switches when the cumulative driving duration reaches a set duration threshold; (3) One of the first master cylinder module and the second master cylinder module can be selected in turn according to the temperature to provide boost pressure for the front axle oil circuit and the rear axle oil circuit. For example, when the temperature of the first master cylinder module is higher than that of the second master cylinder module, switch to the second master cylinder module; when the temperature of the second master cylinder module is higher than that of the second master cylinder module, switch to the first master cylinder module, and so on in a cycle.

[0048] Regarding the control methods of the first master cylinder module and the second master cylinder module, they can also work in proportion and alternate in proportion with each other, that is, first one master cylinder module undertakes a larger proportion of the output, and then switches to the other master cylinder module to undertake a larger proportion of the output. For example: (1) The proportion can be changed according to the number of times. For example, first the first master cylinder module undertakes a larger proportion to perform a boost pressure once, and then the second master cylinder module undertakes a larger proportion to perform a boost pressure once; (2) The proportion can be changed according to time. For example, after the cumulative working duration of the first master cylinder module undertaking a larger proportion reaches a set duration threshold, switch to the second master cylinder module; after the cumulative working duration of the second master cylinder module undertaking a larger proportion reaches a set threshold, switch to the first master cylinder module, and so on in a cycle; or switch according to the vehicle driving duration, that is, switch when the cumulative driving duration reaches a set duration threshold; (3) One of the first master cylinder module and the second master cylinder module can be selected in turn according to the temperature to undertake a larger proportion. For example, when the temperature of the first master cylinder module is higher than that of the second master cylinder module, switch to the second master cylinder module to undertake a larger proportion; when the temperature of the second master cylinder module is higher than that of the second master cylinder module, switch to the first master cylinder module to undertake a larger proportion, and so on in a cycle; (4) The proportion of the first master cylinder module and the second master cylinder module can be calculated in real time according to the temperature. For example, if the temperature ratio of the first master cylinder module and the second master cylinder module is A:B, the power ratio of the first master cylinder module and the second master cylinder module is B:A.

[0049] The device and system embodiments described above are only illustrative. Some or all of the modules can be selected according to actual needs to achieve the purpose of the solution of this embodiment. Those of ordinary skill in the art can understand and implement it without creative efforts.

[0050] The above is only a preferred specific embodiment of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed in the present application should be covered by the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. An electronic hydraulic brake system, characterized in that: It includes an electronic stability control system, an oil pot module, a first master cylinder module and a second master cylinder module; the first master cylinder module and the second master cylinder module both have motors; The oil pot module is connected to the first master cylinder module and the second master cylinder module respectively; the oil pot module is used to provide brake fluid to the first master cylinder module and the second master cylinder module; The first master cylinder module and the second master cylinder module are both connected to the electronic stability control system.

2. The electronic hydraulic brake system according to claim 1, characterized in that: The electronic stability control system includes a first oil circuit and a second oil circuit; The first oil circuit is used to provide braking for the left wheel, and the second oil circuit is used to provide braking for the right wheel; or the first oil circuit is used to provide braking for the right wheel, and the second oil circuit is used to provide braking for the left wheel; or the first oil circuit is used to provide braking for the front axle, and the second oil circuit is used to provide braking for the rear axle; or the first oil circuit is used to provide braking for the rear axle, and the second oil circuit is used to provide braking for the front axle; The output of the first master cylinder module includes two paths, and the output of the second master cylinder module includes two paths; The electronic hydraulic brake system further includes a first valve and a second valve; The first output of the first master cylinder module is directly connected to the first oil circuit; The second output of the first master cylinder module is connected to the second oil circuit through the first valve; The first output of the second master cylinder module is connected to the first oil circuit through the second valve; The second output of the second master cylinder module is directly connected to the second oil circuit.

3. The electronic hydraulic brake system according to claim 1, characterized in that: The braking force provided by the electronic hydraulic braking system for the rear axle and the braking force provided for the front axle increase as the braking demand increases. When the braking demand continues to increase after reaching a set demand threshold, the increase in braking force provided for the rear axle is less than the increase in braking force provided for the front axle.

4. The electronic hydraulic brake system according to claim 1, characterized in that: The first master cylinder module includes a pedal displacement sensor, a first motor module and a first master cylinder; the electronic hydraulic brake system also includes a first valve; The first motor module causes the brake fluid to build up pressure in the first master cylinder according to an output signal of the pedal displacement sensor; The first output of the first master cylinder is directly connected to the electronic stability control system; The second output of the first master cylinder is connected to the electronic stability control system through the first valve.

5. The electronic hydraulic brake system according to claim 1, characterized in that: The second master cylinder module includes a second motor module and a second master cylinder; the electronic hydraulic brake system also includes a second valve; According to the output signal of the first master cylinder module, the second motor module causes the brake fluid to build up pressure in the second master cylinder; The first output of the second master cylinder is connected to the electronic stability control system through the second valve; The second output of the second master cylinder is directly connected to the electronic stability control system.

6. The electronic hydraulic brake system according to claim 5, characterized in that: The second master cylinder module and the first master cylinder module are both connected to the CAN bus, and the second motor module builds up pressure of the brake fluid in the second master cylinder according to the signal output to the CAN bus by the first master cylinder module.

7. The electronic hydraulic brake system according to claim 1, characterized in that: When both the first master cylinder module and the second master cylinder module are operating normally, the first master cylinder module and the second master cylinder module jointly build pressure for the front and rear axles; In the event that the first master cylinder module fails, the second master cylinder module takes over the pressure building of the front and rear axles; In the event that the second master cylinder module fails, the first master cylinder module takes over the pressure building of the front and rear axles.

8. The electronic hydraulic brake system according to claim 1, characterized in that: When both the first master cylinder module and the second master cylinder module operate normally, the first master cylinder module and the second master cylinder module distribute the braking pressure according to a preset ratio.

9. The electronic hydraulic brake system according to claim 1, characterized in that: The electronic stability control system includes a reflux pump. When the electronic stability control system detects that the following conditions are met, the reflux pump is controlled to move so that the pressure is adjusted to the anti-lock braking system triggering level: The hydraulic pressure of the first master cylinder module or the second master cylinder module reaches a high pressure threshold; The pedal displacement sensor detects that the displacement exceeds a displacement threshold; The vehicle speed exceeds the speed threshold.

10. A vehicle, characterized in that: The vehicle comprises the electronic hydraulic brake system according to any one of claims 1 to 9.

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