Brake system integrating hydraulic damping pedal feel and mechanical backup, and braking method

Abstract

The present invention discloses a braking system and a braking method integrating hydraulic damping pedal feel and mechanical backup, belonging to the field of vehicle braking. The braking system includes a brake pedal. The power output end of the brake pedal is aligned with one end of a secondary lever assembly through a primary lever assembly and a first-stage spring assembly in sequence. The other end of the secondary lever assembly is aligned with a hydraulic backup assembly through a second-stage spring assembly. The hydraulic backup assembly is communicated with four brake wheel cylinders through pipelines, and a one-way solenoid valve that conducts unidirectionally towards the brake wheel cylinders is arranged on the pipelines. The stiffness of the first-stage spring assembly is greater than that of the second-stage spring assembly, and a fulcrum is arranged at one end of the secondary lever assembly close to the first-stage spring assembly. The fulcrum is vertically rotatably connected to the mounting shell through a support seat to amplify the pedal feedback force. By adopting the above braking system and braking method integrating hydraulic damping pedal feel and mechanical backup, through the settings of the large and small springs and the secondary lever assembly, a pedal feel with a small stroke and a large damping is achieved, and the pedal simulation experience is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of automotive braking, and particularly to a braking system and a braking method integrating hydraulic damping pedal feel and mechanical backup. Background Art

[0002] In the automotive industry, the development trend of electrification and intelligentization is profoundly changing the pattern of automotive braking systems. From the early traditional vacuum boosters to electronic stability control systems (ESC), electric brake boosters (ibooster), integrated braking systems (one-box), and now the electro-mechanical braking system (EMB) gradually moving towards mass production and application stage, the wire-controlled braking system is constantly innovating, and its core goal is to improve the driving experience and ensure braking safety.

[0003] Among them, when the traditional vacuum booster provides braking assistance, the pedal feel is relatively rigid and cannot accurately meet the pursuit of modern consumers for a comfortable driving experience. The ibooster uses a pure spring type to simulate the foot feel, and there are deficiencies in damping and hysteresis forces, making it difficult to create an ideal pedal feedback. In addition, the performance of these two systems in terms of noise, vibration, and harshness (NVH) is also unsatisfactory, and it is easy to generate noise and vibration during vehicle driving.

[0004] With the development of technology, the EMB emerged. With its 4 sets of independent braking systems, it shows certain advantages in braking performance and can achieve more precise braking force distribution. However, due to the lack of mechanical backup in the EMB, once the electronic system fails, the reliability of the entire braking system will be greatly threatened, which undoubtedly becomes a key factor restricting its wide application. Summary of the Invention

[0005] The purpose of the present invention is to provide a braking system and a braking method integrating hydraulic damping pedal feel and mechanical backup to solve the above technical problems.

[0006] To achieve the above purpose, the present invention provides a braking system integrating hydraulic damping pedal feel and mechanical backup, including a brake pedal. The power output end of the brake pedal is aligned with one end of a secondary lever assembly through a primary lever assembly and a first-stage spring assembly in sequence. The other end of the secondary lever assembly is aligned with a hydraulic backup assembly through a second-stage spring assembly. The hydraulic backup assembly is connected to four brake wheel cylinders through pipelines, and one-way solenoid valves that conduct unidirectionally towards the brake wheel cylinders are arranged on the pipelines.

[0007] The stiffness of the first-stage spring assembly is greater than that of the second-stage spring assembly. The force arm length of the primary lever assembly is less than that of the secondary lever assembly, and a fulcrum is arranged at one end of the secondary lever assembly close to the first-stage spring assembly. The fulcrum is vertically rotatably connected to the mounting shell through a support seat to amplify the pedal feedback force.

[0008] Preferably, a pressure wheel is vertically rotatably connected to the power output position of the brake pedal via a rotating shaft. The pressure wheel is in rolling contact with one end of the primary lever assembly. The other end of the primary lever assembly is vertically rotatably connected to the fulcrum. The rotating connection between the primary lever assembly and the fulcrum is coaxial with the rotating connection between the fulcrum and the mounting housing.

[0009] In the initial state, one end of the primary lever assembly close to the pressure wheel is connected to the power input end of the secondary lever assembly via a spring assembly, and the spring assembly and the pressure wheel are disposed on both sides of the primary lever assembly.

[0010] Preferably, the hydraulic backup assembly is a liquid reservoir.

[0011] The power output end of the secondary lever assembly is connected to one end of a second-stage spring assembly. The other end of the second-stage spring assembly is connected to the power input end of the liquid reservoir. The oil outlet end of the liquid reservoir is communicated with one end of the main pipeline. The other end of the main pipeline is respectively connected to four brake wheel cylinders via four branch pipelines. A one-way solenoid valve is disposed on the main pipeline.

[0012] Preferably, one end of the brake pedal is fixedly connected to the brake pedal body, and the other end extends into the interior of the mounting housing and is vertically rotatably connected to the inner wall of the mounting housing.

[0013] Angle sensors are disposed at the rotating connection between the brake pedal and the mounting housing and at the rotating connection between the fulcrum and the support seat. The angle sensors are connected to the brake wheel cylinders via a domain control ECU, and are used to control the brake wheel cylinders to execute braking forces matching the rotation angle according to the rotation angle of the brake pedal collected by the angle sensors.

[0014] The on-vehicle fault monitoring module is electrically connected to the one-way solenoid valve via the domain control ECU, and is used to open the one-way solenoid valve for braking backup when a mechanical braking fault is detected.

[0015] The one-way solenoid valve is a normally closed solenoid valve.

[0016] Preferably, a rear cover is fixed to one side of the mounting housing. A perforation is left between the rear cover and the mounting housing. The brake pedal passes through the mounting housing via the perforation formed in the mounting housing. Vibration damping pads are disposed on the side of the mounting housing facing the brake pedal and on the side of the rear cover facing the brake pedal, and are used to reduce the noise generated when the brake pedal collides with the perforation wall during braking.

[0017] Preferably, the force relationship formulas of the first-stage spring assembly and the second-stage spring assembly are , where and are respectively the force generated by the first-stage spring assembly and the corresponding force arm, and are respectively the force generated by the second-stage spring assembly and the corresponding force arm, and ;

[0018] The leverage ratio of the end of the secondary lever assembly close to one spring assembly to the end of the secondary lever assembly close to the two-stage spring assembly , is the forward displacement generated by the pressing wheel due to the braking of the brake pedal.

[0019] Preferably, the other side of the mounting shell is connected to the firewall assembly, and the firewall assembly is detachably connected to the vehicle firewall through press rivet screws.

[0020] Preferably, the mounting shell, the brake pedal, the support seat, the primary lever assembly and the secondary lever assembly are all injection molded from PBT+GF30%.

[0021] A braking method for a braking system based on integrating hydraulic damping pedal feel and mechanical backup, including a braking stage and a release stage;

[0022] In the braking stage, under normal conditions, the one-way solenoid valve is in the closed state for mechanical braking. At this time, when the brake pedal is depressed, the brake pedal rotates downward, presses the primary lever assembly downward through the pressing wheel, and then presses one end of the secondary lever assembly downward through the one-stage spring assembly. At this time, under the action of the fulcrum, the other end of the secondary lever assembly compresses the two-stage spring assembly to amplify the pedal feedback force; at the same time, the corner sensor collects the rotation angle of the brake pedal and transmits the angle signal to the domain control ECU. The domain control ECU converts it into a braking force drive command and sends it to the EMB, and the EMB drives the brake wheel cylinder to generate corresponding braking force for braking;

[0023] In the event of a failure, after the failure monitoring module detects a mechanical braking failure, it opens the one-way solenoid valve, and the pedal force drives the hydraulic oil in the reservoir to be output to the brake wheel cylinder to achieve hydraulic braking backup;

[0024] In the release stage, when the brake pedal is released, under the action of the restoring force of the one-stage spring assembly and the two-stage spring assembly, the brake pedal returns to its original position.

[0025] Therefore, the present invention adopts the above-mentioned braking system and braking method that integrate hydraulic damping pedal feel and mechanical backup, and the beneficial effects are as follows:

[0026] 1. Optimize the pedal experience: Adopt a lever and multi-stage wire spring mechanical structure to achieve a small stroke and large damping, non-linear pedal feel; the multi-stage spring is coupled with hydraulic damping to enhance the driving and riding experience; the pedal feel requirements of various vehicle models can also be met by adjusting the leverage ratio and spring stiffness, so that the pedal assembly can withstand a damping force of more than 3000N;

[0027] 2. Ensure functional safety: Integrate multiple corner sensors to achieve redundant and accurate output of pedal displacement, meeting the requirements of future driverless functional safety;

[0028] 3. Reduce the overall weight: The main structure is designed for lightweight using modified engineering plastics, which reduces the overall weight while ensuring high strength.

[0029] 4. Lower the adaptation cost: Adopt an interface platform design. By only adjusting the connection plate interface, it can be matched for installation on different vehicle models, having a cost advantage.

[0030] 5. Ensure reliable braking: The reservoir provides hydraulic damping feeling and reduces noise, and can provide braking during mechanical backup; the one-way solenoid valve opens during mechanical backup, and inputs the hydraulic braking pressure into the caliper to ensure the reliability of the braking system.

[0031] The technical solution of the present invention will be further described in detail below through the drawings and embodiments. Description of the Drawings

[0032] Figure 1 It is a cross-sectional view of the braking system integrating hydraulic damping pedal feeling and mechanical backup according to the present invention;

[0033] Figure 2 It is an external view of the braking system integrating hydraulic damping pedal feeling and mechanical backup according to the present invention.

[0034] Reference Signs

[0035] 1. Installation shell; 2. Hydraulic backup component; 3. Primary lever component; 4. Pressure wheel; 5. Rear cover; 6. Brake pedal; 7. Vibration damping pad; 8. First-stage spring component; 9. Secondary lever component; 10. Support seat; 11. Fulcrum; 12. One-way solenoid valve; 13. Firewall component; 14. Second-stage spring component; 15. Corner sensor. Detailed Embodiment

[0036] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the embodiments of the present invention will be further described in detail below in conjunction with the drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the embodiments of the present invention, and are not used to limit the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts fall within the scope of protection of this application. The examples of the embodiments are shown in the drawings, where the same or similar reference numerals denote the same or similar elements or elements with the same or similar functions throughout.

[0037] It should be noted that the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or server that includes a series of steps or units need not be limited to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to these processes, methods, products, or devices.

[0038] The embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0039] As Figure 1 shown, a braking system integrating hydraulic damping pedal feel and mechanical backup includes a brake pedal 6. The power output end of the brake pedal 6 is aligned with one end of a secondary lever assembly 9 through a primary lever assembly 3 and a first-stage spring assembly 8 in sequence. The other end of the secondary lever assembly 9 is aligned with a hydraulic backup assembly 2 through a second-stage spring assembly 14. The hydraulic backup assembly 2 is connected to four brake wheel cylinders through pipelines, and a one-way solenoid valve 12 that conducts unidirectionally towards the brake wheel cylinders is arranged on the pipeline; the stiffness of the first-stage spring assembly 8 is greater than that of the second-stage spring assembly 14, the force arm length of the primary lever assembly 3 is less than that of the secondary lever assembly 9, and a fulcrum 11 is arranged at one end of the secondary lever assembly 9 close to the first-stage spring assembly 8. The fulcrum 11 is vertically rotatably connected to the mounting shell 1 through a support seat to amplify the pedal feedback force.

[0040] A pressure wheel 4 is vertically rotatably connected to the power output position of the brake pedal 6 through a rotating shaft. The pressure wheel 4 is in rolling contact with one end of the primary lever assembly 3. The other end of the primary lever assembly 3 is vertically rotatably connected to the fulcrum 11. The rotation connection between the primary lever assembly 3 and the fulcrum 11 is coaxial with the rotation connection between the fulcrum 11 and the mounting shell 1; in the initial state, one end of the primary lever assembly 3 close to the pressure wheel 4 is connected to the power input end of the secondary lever assembly 9 through a first-stage spring assembly 8, and the first-stage spring assembly 8 and the pressure wheel 4 are respectively arranged on both sides of the primary lever assembly 3. As Figure 2 shown, through the above structure, when the stroke of the depressed brake pedal 6 advances, the closer the pressure wheel 4 is to the fulcrum 11 (the pressure wheel 4 rolls on the primary lever assembly 3), the greater the pedal feedback force, improving the pedal feel.

[0041] The hydraulic backup assembly 2 is a liquid reservoir; the power output end of the secondary lever assembly 9 is connected to one end of the second-stage spring assembly 14. The other end of the second-stage spring assembly 14 is connected to the power input end of the liquid reservoir. The oil outlet end of the liquid reservoir is connected to one end of the main pipeline. The other end of the main pipeline is respectively connected to four brake wheel cylinders through four branch pipelines.

[0042] One end of the brake pedal 6 is fixedly connected to the brake pedal 6, and the other end extends into the interior of the mounting shell 1 and is vertically rotatably connected to the inner wall of the mounting shell 1; angle sensors 15 are provided at the rotational connection between the brake pedal 6 and the mounting shell 1 and at the rotational connection between the fulcrum 11 and the support seat 10. The angle sensors 15 are connected to the brake wheel cylinder via the domain control ECU and are used to control the brake wheel cylinder to execute a braking force matching the rotational angle according to the rotational angle of the brake pedal 6 collected by the angle sensors 15; the vehicle-mounted fault monitoring module is electrically connected to the one-way solenoid valve 12 via the domain control ECU and is used to open the one-way solenoid valve 12 for braking backup when a mechanical braking fault is detected; the one-way solenoid valve 12 is a normally closed solenoid valve.

[0043] A rear cover 5 is fixed to one side of the mounting shell 1. There is a perforation between the rear cover 5 and the mounting shell 1. The brake pedal 6 passes through the perforation provided on the mounting shell 1 and penetrates into the mounting shell 1. Vibration damping pads 7 are provided on the side of the mounting shell 1 facing the brake pedal 6 and on the side of the rear cover 5 facing the brake pedal 6, which are used to reduce the noise generated when the brake pedal 6 collides with the perforation wall during braking.

[0044] The force relationship formula of the first-stage spring assembly 8 and the second-stage spring assembly 14 is , where and are the force generated by the first-stage spring assembly 8 and the corresponding force arm respectively, and are the force generated by the second-stage spring assembly 14 and the corresponding force arm respectively, and ; the lever ratio of the end of the secondary lever assembly 9 close to the first-stage spring assembly 8 to the end of the secondary lever assembly 9 close to the second-stage spring assembly 14 is , is the forward displacement generated by the pressing wheel 4 following the braking of the brake pedal 6. Through the above settings, during braking, the brake pedal 6 moves and compresses the first-stage spring assembly 8 downward until the first-stage spring assembly 8 coils up. Under the action of the secondary lever assembly 9, the second-stage spring assembly 14 is compressed, and with the effect of the variable lever ratio (the rolling of the pressing wheel 4 causes the lever ratio to change), the feedback force is increased, meeting the design requirements of the pedal feel curve.

[0045] The other side of the mounting shell 1 is connected to the firewall assembly 13. The firewall assembly 13 is detachably connected to the vehicle firewall via rivet screws. The detachable connection method can adapt to different vehicle models by replacing different firewall assemblies 13, broadening the ductility.

[0046] The mounting shell 1, the brake pedal 6, the support seat 10, the primary lever assembly 3, and the secondary lever assembly 9 are all injection molded from PBT+GF30%, achieving weight reduction while reducing costs.

[0047] A braking method for a braking system based on integrated hydraulic damping pedal feel and mechanical backup, including a braking stage and a release stage;

[0048] In the braking stage, under normal conditions, the one-way solenoid valve 12 is in the closed state for mechanical braking. At this time, when the brake pedal 6 is depressed, the brake pedal 6 rotates downward, presses down on the primary lever assembly 3 through the pressure wheel 4, and then presses down on one end of the secondary lever assembly 9 through a spring assembly 8. At this time, under the action of the fulcrum 11, the other end of the secondary lever assembly 9 compresses the second-stage spring assembly 14 to amplify the pedal feedback force; at the same time, the angle sensor 15 collects the rotation angle of the brake pedal 6 and transmits the angle signal to the domain control ECU. The domain control ECU converts it into a braking force drive command and sends it to the EMB. The EMB drives the brake wheel cylinder to generate the corresponding braking force for braking;

[0049] In the event of a failure, after the failure monitoring module detects a mechanical braking failure, it opens the one-way solenoid valve 12, and the pedal force drives the hydraulic oil in the reservoir to be output to the brake wheel cylinder to achieve hydraulic braking backup;

[0050] In the release stage, when the brake pedal 6 is released, under the action of the restoring force of the first-stage spring assembly 8 and the second-stage spring assembly 14, the brake pedal 6 returns to its original position.

[0051] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit them. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that they can still modify or equivalently replace the technical solutions of the present invention, and these modifications or equivalent replacements do not make the modified technical solutions deviate from the spirit and scope of the technical solutions of the present invention.

Claims

1. An integrated hydraulic damping pedal feel and mechanical backup braking system, including a brake pedal, characterized in that: The power output end of the brake pedal is aligned with one end of the secondary lever assembly through the primary lever assembly and the first-stage spring assembly in sequence. The other end of the secondary lever assembly is aligned with the hydraulic backup assembly through the second-stage spring assembly. The hydraulic backup assembly is connected to four brake wheel cylinders through pipelines, and a one-way solenoid valve that conducts unidirectionally towards the brake wheel cylinders is arranged on the pipeline. The stiffness of the first-stage spring assembly is greater than that of the second-stage spring assembly. The force arm length of the primary lever assembly is less than that of the secondary lever assembly. A fulcrum is arranged at one end of the secondary lever assembly close to the first-stage spring assembly. The fulcrum is vertically rotatably connected to the mounting shell through a support seat to amplify the pedal feedback force. A pressure wheel is vertically rotatably connected to the power output position of the brake pedal through a rotating shaft. The pressure wheel is in rolling contact with one end of the primary lever assembly. The other end of the primary lever assembly is vertically rotatably connected to the fulcrum. The fulcrum is rotatably connected to the support seat fixed on the inner wall of the mounting shell. In the initial state, one end of the primary lever assembly close to the pressure wheel is connected to the power input end of the secondary lever assembly through the first-stage spring assembly, and the first-stage spring assembly and the pressure wheel are respectively arranged on both sides of the primary lever assembly. The hydraulic backup assembly is a liquid reservoir. The power output end of the secondary lever assembly is connected to one end of the second-stage spring assembly. The other end of the second-stage spring assembly is connected to the power input end of the liquid reservoir. The oil outlet end of the liquid reservoir is connected to one end of the main pipeline. The other end of the main pipeline is respectively connected to four brake wheel cylinders through four branch pipelines. Corner sensors are arranged at the rotational connection between the brake pedal and the mounting shell and at the rotational connection between the fulcrum and the support seat. The corner sensors are connected to the brake wheel cylinders through the domain control ECU and are used to control the brake wheel cylinders to execute braking force matching the rotational angle according to the rotational angle of the brake pedal collected by the corner sensors. The on-vehicle fault monitoring module is electrically connected to the one-way solenoid valve through the domain control ECU and is used to open the one-way solenoid valve for braking backup when a mechanical braking fault is detected. The one-way solenoid valve is a normally closed solenoid valve. The braking method of the braking system integrating hydraulic damping pedal feeling and mechanical backup includes a braking stage and a release stage. In the braking stage, under normal conditions, the one-way solenoid valve is in the closed state for mechanical braking. At this time, when the brake pedal is depressed, the brake pedal rotates downward, presses the primary lever assembly downward through the pressure wheel, and then presses one end of the secondary lever assembly downward through the first-stage spring assembly. At this time, under the action of the fulcrum, the other end of the secondary lever assembly compresses the second-stage spring assembly to amplify the pedal feedback force. At the same time, the corner sensor collects the rotational angle of the brake pedal and transmits the angle signal to the domain control ECU. The domain control ECU converts it into a braking force driving instruction and sends it to the EMB. The EMB drives the brake wheel cylinders to generate corresponding braking force for braking. In the fault state, after the fault monitoring module detects a mechanical braking fault, it opens the one-way solenoid valve, and the pedal force drives the hydraulic oil in the liquid reservoir to be output to the brake wheel cylinders to achieve hydraulic braking backup. In the release stage, when the brake pedal is released, the brake pedal returns to its original position under the action of the restoring forces of the first-stage spring assembly and the second-stage spring assembly.

2. The integrated hydraulic damping pedal feel and mechanical backup braking system according to claim 1, wherein: A rear cover is fixed to one side of the mounting shell. There is a perforation between the rear cover and the mounting shell. The brake pedal passes through the perforation formed on the mounting shell and into the mounting shell. A damping pad is provided on the side of the mounting shell facing the brake pedal and on the side of the rear cover facing the brake pedal to reduce the noise generated when the brake pedal collides with the perforation wall during braking.

3. The integrated hydraulic damping pedal feel and mechanical backup braking system according to claim 1, characterized in that: The force relationship between the first-stage spring assembly and the second-stage spring assembly is , where and are the force generated by the first-stage spring assembly and the corresponding force arm respectively, and are the force generated by the second-stage spring assembly and the corresponding force arm respectively, and ; The lever ratio of the secondary lever assembly near one end of the spring assembly to the secondary lever assembly near the two-stage spring assembly , is the forward displacement generated by the pressing wheel due to the braking of the brake pedal.

4. The integrated hydraulic damping pedal feel and mechanical backup braking system according to claim 1, wherein: The other side of the mounting shell is connected to the firewall assembly. The firewall assembly is detachably connected to the vehicle firewall via press rivet screws.

5. The integrated hydraulic damping pedal feel and mechanical backup braking system according to claim 1, characterized in that: The mounting shell, the brake pedal, the support seat, the primary lever assembly, and the secondary lever assembly are all injection molded from PBT+GF30%.

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