An electromechanical brake caliper and a control method thereof

Abstract

The present application relates to a kind of electronic mechanical brake calipers, including shell, brake disc and brake pad, further including actuating assembly and electromagnetic actuator, actuating assembly is arranged in shell, actuating assembly includes motor, transmission structure, conversion mechanism and piston, the power output end of motor is connected with the power input end of conversion mechanism by transmission structure, conversion mechanism can convert the rotary motion of its power input end into the linear motion of its power output end, the linear motion of the power output end of conversion mechanism can promote piston to drive brake pad and resist tight brake disc, electromagnetic actuator is arranged between shell and piston, electromagnetic actuator is used to exert force on piston in the direction away from brake disc.The present application also proposes a kind of electronic mechanical brake caliper control method.The present application can reduce even eliminate the drag force of electronic mechanical brake caliper, with the characteristics of simple structure, high integration and reliable performance.

Description

Technical Field

[0001] This invention relates to brake calipers, and more specifically to an electromechanical brake caliper and its control method. Background Technology

[0002] In today's rapidly developing society, economy, and science and technology, while pursuing vehicle power and comfort, people are also paying increasing attention to vehicle safety. Among these, braking performance is particularly important, as it directly relates to the safety of life and property; good braking performance is a fundamental guarantee for safe driving.

[0003] The hydraulic braking system, widely used in existing vehicles, mainly consists of a brake pedal, master cylinder, vacuum booster, hydraulic lines, wheel cylinders, and brakes. When braking is required, the driver depresses the brake pedal. Under the action of a series of mechanical structures and the vacuum booster, hydraulic fluid in the master cylinder flows at a certain pressure through the brake lines into each wheel cylinder, ultimately driving the disc or drum brakes to complete the braking action, thus achieving wheel braking. After a long period of development, hydraulic braking has become a very mature technology, and almost all current passenger cars use hydraulic braking systems.

[0004] Although hydraulic braking systems have been widely used, they also have the following problems: Hydraulic braking systems have numerous mechanical components and hydraulic lines, and the vacuum booster is relatively large. Especially after integrating electronic control functions such as ABS, TCS, and ESP, hydraulic braking systems become even more complex, making layout and assembly difficult. The hydraulic oil in hydraulic braking systems needs to be replaced regularly, and there is a risk of hydraulic oil leakage during use, which can easily cause environmental pollution. For new energy vehicles with brake energy recovery systems but lacking a vacuum booster source, the use of hydraulic braking systems is limited, and matching them is difficult.

[0005] With the development of science and technology, electromechanical braking systems, characterized by their more compact structure, greater braking force, and more reliable operation, have emerged. Because they can solve the problems that have plagued hydraulic braking systems for many years, electromechanical braking systems have become a trend in braking technology research. Compared to traditional hydraulic braking systems, electromechanical braking systems use electricity as their energy source. A motor drives the brake pads to press against the brake disc to achieve the braking function, with energy transmitted via electrical wires and signals transmitted via data lines. The high efficiency of electromechanical braking systems greatly improves vehicle braking safety.

[0006] The electromechanical brake calipers in existing electromechanical braking systems typically suffer from technical problems such as complex structure, large drag force, low integration, high response delay, and low redundancy. Summary of the Invention

[0007] The purpose of this invention is to provide an electromechanical brake caliper and its control method to alleviate or eliminate at least one of the above-mentioned technical problems.

[0008] The present invention discloses an electromechanical brake caliper, comprising a housing, a brake disc, and brake pads, and further comprising an actuation assembly and an electromagnetic actuator. The actuation assembly is disposed in the housing and includes a motor, a transmission structure, a conversion mechanism, and a piston. The power output end of the motor is connected to the power input end of the conversion mechanism through the transmission structure. The conversion mechanism can convert the rotational motion of its power input end into linear motion of its power output end. The linear motion of the power output end of the conversion mechanism can push the piston to drive the brake pads to press against the brake disc. The electromagnetic actuator is disposed between the housing and the piston, and the electromagnetic actuator is used to apply a force to the piston in a direction opposite to that of the brake disc.

[0009] Optionally, the conversion mechanism includes a screw and a nut threadedly engaged with the screw, the screw being connected to the power output end of the transmission structure, and one end of the nut abutting against the piston.

[0010] Optionally, the housing is provided with a first mounting hole, the piston is slidably engaged with the first mounting hole, and a sealing ring is provided between the piston and the first mounting hole.

[0011] Optionally, a spring is provided between the brake pad and the housing, the spring being used to apply a force to the brake pad in a direction opposite to that of the brake disc.

[0012] Optionally, the electromagnetic actuator includes a permanent magnet and an electromagnetic coil, the permanent magnet and the electromagnetic coil being fixedly connected to the housing and the piston, respectively.

[0013] Optionally, the actuation assembly includes at least two of the motors.

[0014] Optionally, a brake pad is provided on each side of the brake disc, and two actuation components are provided in the housing. One actuation component can drive one brake pad to press against the brake disc, and the other actuation component can drive the other brake pad to press against the brake disc.

[0015] Optionally, a brake controller is fixedly connected to the housing.

[0016] Optionally, the transmission structure includes a transmission mechanism and a reduction mechanism. The power output end of the motor is connected to the power input end of the transmission mechanism, the power output end of the transmission mechanism is connected to the power input end of the reduction mechanism, and the power output end of the reduction mechanism is connected to the power input end of the conversion mechanism. The transmission mechanism is a fixed-axis gear train transmission mechanism, and the reduction mechanism is a two-stage planetary gear reduction mechanism.

[0017] The present invention also proposes an electromechanical brake caliper control method for controlling the electromechanical brake caliper described in any of the above claims. The electromechanical brake caliper control method includes the following steps: in response to receiving a release command, controlling an electromagnetic actuator to operate such that the electromagnetic actuator applies a force to the piston in a direction opposite to that of the brake disc.

[0018] This invention can reduce or even eliminate the drag force of electromechanical brake calipers, and features simple structure, high integration and reliable performance. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the electromechanical brake caliper described in the specific implementation embodiment;

[0020] Figure 2 for Figure 1 Enlarged view of section A;

[0021] Figure 3 for Figure 2 Enlarged view of section A;

[0022] Figure 4 This is a schematic diagram of the conversion mechanism described in the specific implementation embodiment;

[0023] Figure 5 This is a flowchart of the electromechanical brake caliper control method described in a specific implementation.

[0024] Among them, 1-brake caliper housing; 2-brake disc; 3-brake pad; 4-motor; 5-transmission mechanism; 6-reduction mechanism; 7-conversion mechanism; 8-piston; 9-reduction gearbox housing; 10-brake controller; 11-wear alarm; 12-spring; 13-electromagnetic coil; 14-permanent magnet; 15-sealing ring; 16-thrust needle roller bearing; 17-copper sleeve;

[0025] 101 - First mounting hole; 102 - Second mounting hole;

[0026] 501 - Intermediate shaft; 502 - First transmission gear; 503 - Second transmission gear; 504 - Third transmission gear; 505 - Transmission output shaft;

[0027] 601-First sun gear; 602-First planet gear; 603-First internal gear ring; 604-First planet carrier; 605-Second sun gear; 606-Second planet gear; 607-Second internal gear ring; 608-Second planet carrier;

[0028] 701-Screw; 702-Limiting boss; 703-Nut; 704-Conical surface. Detailed Implementation

[0029] The embodiments of the present invention will be described below with reference to the accompanying drawings and preferred embodiments. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be understood that the preferred embodiments are only for illustrating the present invention and not for limiting the scope of protection of the present invention.

[0030] It should be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of the present invention. Therefore, the drawings only show the components related to the present invention and are not drawn according to the actual number, shape and size of the components in the actual implementation. In the actual implementation, the form, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0031] like Figures 1 to 4 An electromechanical brake caliper includes a housing, a brake disc 2, and a brake pad 3. It also includes an actuation assembly and an electromagnetic actuator. The actuation assembly is disposed in the housing and includes a motor 4, a transmission structure, a conversion mechanism 7, and a piston 8. The power output end of the motor 4 is connected to the power input end of the conversion mechanism 7 through the transmission structure. The conversion mechanism 7 can convert the rotational motion of its power input end into the linear motion of its power output end. The linear motion of the power output end of the conversion mechanism 7 can push the piston 8 to drive the brake pad 3 to press against the brake disc 2. The electromagnetic actuator is disposed between the housing and the piston 8. The electromagnetic actuator is used to apply a force to the piston 8 in a direction away from the brake disc 2.

[0032] By adopting the above technical solution, when releasing the static parking / dynamic parking, the electromagnetic actuator can provide a return force to the piston 8, thereby ensuring the return of the piston 8 and helping to reduce the drag torque of the entire electromechanical brake caliper.

[0033] In some embodiments, the conversion mechanism 7 includes a screw 701 and a nut 703 threadedly engaged with the screw 701. The screw 701 is connected to the power output end of the transmission structure, and one end of the nut 703 abuts against the piston 8. Using the above technical solution, the rotation of the screw 701 drives the nut 703 to move axially along the screw 701, thereby converting the rotational movement of the screw 701 into the linear motion of the nut 703. This allows the nut 703 to push the piston 8 to generate braking force, resulting in a simple structure. Simultaneously, the self-locking characteristics of the screw 701 and the nut 703 enable the electromechanical brake caliper to be used as a parking brake caliper. In a specific implementation, the screw 701 is provided with a multi-start sawtooth thread for threaded engagement with the nut 703.

[0034] In some embodiments, a limiting boss 702 is provided on the outer side of the screw 701. The limiting boss 702 is used to cooperate with the anti-rotation sleeve mounted on the housing to limit the rotation angle range of the screw 701, thereby improving the reliability of the electromechanical brake caliper.

[0035] In some embodiments, a tapered surface 704 is provided at one end of the nut 703. The tapered surface 704 engages with the tapered hole on the piston 8, which can increase the contact area between the piston 8 and the nut 703, and help prevent the nut 703 from rotating relative to the piston 8.

[0036] In some embodiments, a first mounting hole 101 is provided in the housing, the piston 8 is slidably engaged with the first mounting hole 101, and a sealing ring 15 is provided between the piston 8 and the first mounting hole 101. Using the above technical solution, on the one hand, the piston 8 can seal the gap between the piston 8 and the first mounting hole 101; on the other hand, the sealing ring 15 is clamped between the piston 8 and the first mounting hole 101, and the sealing ring 15 is interference-fitted with the piston 8. The sealing ring 15 can apply a force to the piston 8 to prevent rotation, thereby ensuring that the piston 8 and the nut 703 move linearly together, providing a basis for using the screw 701 and the nut 703 to form the conversion mechanism 7. Furthermore, the conversion mechanism 7 composed of the screw 701 and the nut 703 works in conjunction with the electromagnetic actuator, which can use the electromagnetic actuator to apply a force to the piston 8 to increase the force between the piston 8 and the nut 703, thereby increasing the friction between the piston 8 and the nut 703, which helps to prevent the nut 703 from rotating relative to the piston 8. In specific implementation, an annular groove for fitting the sealing ring 15 is provided on the wall of the first mounting hole 101.

[0037] In some embodiments, a spring 12 is provided between the brake pad 3 and the housing, and the spring 12 is used to apply a force to the brake pad 3 in a direction away from the brake disc 2. By adopting the above technical solution, the spring 12 can promote the return of the brake pad 3, so that a gap is formed between the brake pad 3 and the brake disc 2, thereby reducing or even eliminating the drag torque of the entire electromechanical brake caliper.

[0038] In some embodiments, the electromagnetic actuator includes a permanent magnet 14 and an electromagnetic coil 13, which are respectively fixedly connected to the housing and the piston 8. Using the above technical solution, by energizing the electromagnetic coil 13, an attractive or repulsive force can be generated between the electromagnetic coil 13 and the permanent magnet 14. By adjusting the magnitude and direction of the current in the electromagnetic coil 13, the magnitude and direction of the force between the electromagnetic coil 13 and the permanent magnet 14 can be adjusted. When the electromechanical brake caliper malfunctions or requires further adjustment of the drag torque, the electromagnetic actuator can drive the piston 8 back to its original position, providing a convenient piston 8 return function for vehicle maintenance and fault diagnosis. As a specific example, the electromagnetic coil 13 is fixedly mounted on the piston 8, and the permanent magnet 14 is fixedly mounted in the first mounting hole 101.

[0039] In some embodiments, the actuation component includes two motors 4. Using the above-described technical solution, braking is achieved by driving one brake pad 3 with two motors 4. The two motors 4 serve as safety backups for each other, improving the reliability of the electromechanical brake caliper.

[0040] In some embodiments, the two motors 4 of each actuation component are respectively arranged around the periphery of the conversion mechanism 7, and the central axes of the two motors 4 are parallel to the central axis of the conversion mechanism 7. By reasonably setting the position of the motors 4, the volume of the electromechanical brake caliper can be reduced, and the layout difficulty of the transmission structure can be lowered. Obviously, in other embodiments, the number of motors 4 can be set according to actual needs.

[0041] In some embodiments, the brake disc 2 is a high-performance ceramic carbon brake disc. Compared with the traditional gray cast iron brake disc 2, the high-performance ceramic carbon brake disc is lightweight and has better thermal performance, which can further improve braking performance, meet more stringent AMS and hot melt performance indicators, and is more competitive in the market.

[0042] In some embodiments, a torque sensor is provided between the piston 8 and the brake pad 3, which can monitor the braking torque of the electromechanical brake caliper in real time via CAN signal / instrumentation, thereby realizing loop-in monitoring of the output braking torque and providing signal identification reference for vehicle maintenance and fault diagnosis.

[0043] In some embodiments, a wear alarm 11 is provided on the brake pad 3, which can mechanically remind the user based on the wear condition of the brake pad 3, thus helping to ensure the reliability of the electromechanical brake caliper.

[0044] In some embodiments, a brake pad 3 is provided on each side of the brake disc 2, and two actuating components are provided in the housing. One actuating component can drive one brake pad 3 to press against the brake disc 2, and the other actuating component can drive the other brake pad 3 to press against the brake disc 2. By adopting the above technical solution, and by providing two brake pads 3 and using two actuating components to act on the two brake pads 3 respectively, on the one hand, the braking force of the electromechanical brake caliper can be improved, thus enhancing the braking performance of the electromechanical brake caliper; on the other hand, the two actuating components serve as safety backups for each other, improving the reliability of the electromechanical brake caliper. In a specific implementation, the two brake pads 3 are respectively positioned relative to the brake disc 2 on the side facing outwards and the side facing inwards, and the two actuating components are respectively positioned relative to the brake disc 2 on the side facing outwards and the side facing inwards.

[0045] In some embodiments, a brake controller 10 is fixedly connected to the housing. As a preferred example, the brake controller 10 is fixedly connected to the side of the housing closest to the vehicle interior. By adopting the above technical solution, fixing the brake controller 10 to the housing improves the integration of the electromechanical brake caliper. Placing the brake controller 10 on the side of the housing closest to the vehicle interior reduces the possibility of damage to the brake controller 10. The brake controller 10 can receive signal input from driving intentions or the central controller, accurately control the speed and output torque of the motor 4, and generate corresponding braking force and motor 4 braking force distribution in real time. This invention integrates the brake controller 10 with the electromechanical brake caliper into one unit, which can shorten system communication time, simplify algorithms, and develop TCS, EDC, ABS and other functions at the wheel end, thereby effectively solving the problem of system response delay.

[0046] In some embodiments, the transmission structure includes a transmission mechanism 5 and a reduction mechanism 6. The power output ends of the two motors 4 are respectively connected to the two power input ends of the transmission mechanism 5. The power output end of the transmission mechanism 5 is connected to the power input end of the reduction mechanism 6. The power output end of the reduction mechanism 6 is connected to the power input end of the conversion mechanism 7. The transmission mechanism 5 is a fixed-axis gear train transmission mechanism. The reduction mechanism 6 is a two-stage planetary gear reduction mechanism. The above-mentioned technical solution uses two motors 4 to reduce speed and increase torque through the same reduction mechanism 6. This approach has advantages such as simple structure and fewer parts, which helps control costs and reduce failure rates. However, if each motor has its own reduction mechanism for speed reduction and torque increase, and the torque output from both reduction mechanisms is then transmitted to the conversion mechanism via a transmission mechanism, it's difficult to ensure synchronous rotation between the two motors. The reduction mechanism corresponding to the later-rotating motor will hinder the earlier-rotating motor from driving the later-rotating motor, resulting in significant drag force. This is especially true when both reduction mechanisms use planetary gear reduction mechanisms, which are prone to generating substantial drag force. Therefore, the solution of using a separate reduction mechanism for each motor and transmitting the torque output from both reduction mechanisms to the conversion mechanism via a transmission mechanism is impractical and cannot meet the requirements of real-world vehicle use. In contrast, the solution of using two motors 4 to reduce speed and increase torque through the same reduction mechanism 6 can reduce or eliminate the drag force problem caused by the two motors 4 in the actuation components. It achieves safety backup and increases redundancy while also reducing or eliminating drag force, meeting the requirements of real-world vehicle use and making it feasible for practical application.

[0047] In some embodiments, the transmission mechanism 5 is a fixed-axis gear train transmission mechanism; the two motors 4 are connected to the reduction mechanism 6 via the fixed-axis gear train transmission mechanism, which helps to reduce or eliminate the drag force generated by the actuation component due to the presence of two motors 4. As a specific example, the transmission mechanism 5 includes two motor output gears, two double gears, a third transmission gear 504, and a transmission output shaft 505 connected to the third transmission gear 504. The two motor output gears are respectively mounted on the output shafts of the two motors 4. Each of the two double gears is provided with a first transmission gear 502 and a second transmission gear 503. The two first transmission gears 502 mesh with the two motor output gears respectively, and the two second transmission gears 503 mesh with the third transmission gear 504. The transmission output shaft 505 is connected to the power input end of the reduction mechanism 6. In a specific implementation, the first transmission gear 502 and the second transmission gear 503 are connected via an intermediate shaft 501 to form a double gear. In a specific implementation, the gears can be mounted on shafts via key connections to achieve synchronous rotation. The intermediate shaft 501, motor output shaft, and transmission output shaft 505 can all be rotatably mounted in the housing via bearings. Using this design, a single transmission mechanism 5 can transmit power between at least two motors 4 and the reduction mechanism 6. The double gear transmission between the motor output gear and the third transmission gear 504 reduces the complexity of arranging the transmission mechanism 5 and helps prevent dragging forces. Furthermore, the fixed-axis gear train transmission mechanism can transmit a large torque, meeting the needs of vehicles with significant weight.

[0048] In some embodiments, the reduction mechanism 6 is a two-stage planetary gear reduction mechanism. A two-stage planetary gear reduction mechanism can reduce speed and increase torque. The transmission ratio of a two-stage planetary gear reduction mechanism is generally large, and under the same transmission ratio, its volume is much smaller than that of a conventional cylindrical gear reducer. Furthermore, the power input and output ends of a two-stage planetary gear reduction mechanism are coaxial, resulting in smooth operation, strong impact resistance, and strong vibration resistance. The two-stage planetary gear reduction mechanism has the following advantages: a wide transmission ratio range, high load-bearing capacity, small size, light weight, smooth transmission, high efficiency, reliable operation, and long service life. In practical implementation, the two-stage planetary gear reduction mechanism includes a first sun gear 601, a first internal gear ring 603, a first planet carrier 604, multiple first planet gears 602, a second sun gear 605, a second internal gear ring 607, a second planet carrier 608, and multiple second planet gears 606. The first internal gear ring 603 and the second internal gear ring 607 are fixedly connected to the housing. The first sun gear 601 is connected to the power output end of the transmission mechanism 5 and rotates synchronously. The multiple first planet gears 602 are rotatably mounted on the first planet carrier 604. 602 meshes between the first internal gear ring 603 and the first sun gear 601. The second sun gear 605 is connected to the first planet carrier 604 and rotates synchronously. Multiple second planet gears 606 are rotatably mounted on the second planet carrier 608. Multiple second planet gears 606 mesh between the second internal gear ring 607 and the second sun gear 605. The second planet carrier 608 is connected to the power input end of the conversion mechanism 7 and rotates synchronously. The first sun gear 601 serves as the power input component of the reduction mechanism 6, and the second planet carrier 608 serves as the power output component of the reduction mechanism 6.

[0049] In some embodiments, both motors 4 are brushless DC motors. Brushless DC motors use electronic commutation instead of brushes and commutators, eliminating sparks and wear, thus resulting in high reliability and long lifespan. Brushless DC motors are significantly smaller in weight and size than brushed DC motors, reducing weight by approximately 70% and moment of inertia by about 40% to 50%. Furthermore, brushless DC motors also exhibit linear torque-speed characteristics similar to ordinary DC motors 4. Brushless DC motors can be further classified into various types based on the permanent magnet material used. Among them, rare-earth permanent magnet brushless DC motors offer advantages such as high starting torque, strong overload capacity, convenient speed adjustment, smooth operation, low noise, and reliable operation, making them ideal energy-saving, noise-reducing, and environmentally friendly products. As a preferred example, both motors 4 are rare-earth permanent magnet brushless DC motors.

[0050] In some embodiments, the stator of the brushless DC motor surrounds the rotor of the brushless DC motor, the permanent magnet of the brushless DC motor is disposed on the rotor of the brushless DC motor, the stator of the brushless DC motor mates with the second mounting hole 102 on the housing, and the output shaft of the brushless DC motor is fixedly connected to the stator of the brushless DC motor. By using the above scheme, mounting the permanent magnet on the rotor of the brushless DC motor prevents the rotor from generating heat, thereby reducing the losses of the brushless DC motor and improving efficiency. The stator of the brushless DC motor can dissipate heat through the housing, thus improving heat dissipation conditions.

[0051] In some embodiments, the housing includes a brake caliper housing 1 and a gearbox housing 9 fixedly connected to the brake caliper housing 1. The conversion mechanism 7 and two motors 4 are both disposed in the brake caliper housing 1, and the transmission mechanism 5 and the reduction mechanism 6 are both disposed in the gearbox housing 9. The motor output shafts of the two motors 4 extend into the gearbox housing 9, and the second planetary carrier 608 of the reduction mechanism 6 extends into the brake caliper housing 1, or the lead screw of the conversion mechanism 7 extends into the gearbox housing 9. By providing the gearbox housing 9 to support the transmission mechanism 5 and the reduction mechanism 6, the arrangement difficulty of the transmission mechanism 5 and the reduction mechanism 6 can be reduced, offering advantages in ease of assembly and disassembly. In specific implementations, the shafts of the transmission mechanism 5 and the reduction mechanism 6 can be rotatably connected within the gearbox housing 9. This rotatable connection can be achieved by placing bearings between the shafts and the gearbox housing 9. The first internal gear ring 603 and the second internal gear ring 607 of the reduction mechanism 6 can be fixedly connected within the gearbox housing 9 by an interference fit. The brake caliper housing 1 transmits force during braking, supports the piston 8 to generate braking force, and provides a hard point or interface for fixed mounting to the vehicle's steering knuckle. A first mounting hole 101 and a second mounting hole 102 are provided within the brake caliper housing 1, and the stator of the brushless DC motor is interference-fitted with the second mounting hole 102. As a preferred embodiment, a copper sleeve 17 and a thrust needle roller bearing 16 are provided between the screw 701 and the brake caliper housing 1 to reduce friction.

[0052] In some embodiments, the arrangement of the housing, brake disc 2 and brake pad 3 can refer to the solutions in the prior art. The brake pad 3 can be slidably connected to the housing through a linear motion structure. The piston 8 pushes the brake pad 3 to make the brake pad 3 press against the brake disc 2, thereby achieving braking.

[0053] Using the aforementioned electromechanical brake caliper, after being powered on, the motor 4 generates torque and speed output. Through the transmission mechanism 5 and the reduction mechanism 6, the torque is increased, driving the screw 701 to rotate, thereby pushing the nut 703 to move linearly, pushing out the piston 8 to generate braking force. The magnitude and direction of the braking force can be controlled by the magnitude and direction of the input current to the motor 4. Parking braking is achieved by controlling the forward and reverse rotation of the motor 4. If the rotation direction of the motor 4 is positive braking torque when the brake is engaged, when the vehicle needs static or dynamic parking, the EPB switch is pulled up, and the positive torque parking control algorithm controls the electromechanical brake caliper to output parking force in real time. When the vehicle needs to release static / dynamic parking, the EPB switch is released, and the negative torque control algorithm rotates the nut 703 back, thereby releasing the electromechanical brake caliper parking force.

[0054] In practical implementation, the aforementioned electromechanical brake calipers can be used in a braking system. The braking system typically includes four electromechanical brake calipers, a brake pedal, a central controller, and an ABS control module. The four electromechanical brake calipers, brake pedal, central controller, and ABS control module are connected via communication lines. An electromechanical pedal simulator can be used for the brake pedal.

[0055] The aforementioned braking system is an electromechanical braking system. Compared to traditional hydraulic braking systems, the electromechanical braking system uses electrical energy as its energy source. The motor 4 drives the brake pads 3 to press against the brake disc 2 to achieve the braking function. Energy is transmitted via electrical wires, and signals are transmitted via data lines. The simple structure and high efficiency of the electromechanical braking system greatly improve vehicle braking safety. Compared to traditional hydraulic braking systems, the electromechanical braking system has the following advantages: fewer mechanical connections, no hydraulic brake lines, effectively reducing vehicle weight; simple structure, small size, and easy installation; rapid signal transmission, fast braking response, and sensitive reaction due to the use of mechanical and electrical connections; high transmission efficiency and energy saving; powerful electronic intelligent control functions, which can achieve complex electronic control functions such as ABS, TCS, ESP, and ACC by modifying the software program in the ECU and configuring relevant parameters, and are easily matched with new energy vehicles with braking energy recovery systems; the electromechanical braking system adopts a modular structure, making assembly simple and maintenance convenient; and it uses an electronic pedal. The elimination of the mechanical and hydraulic connection between the brake pedal and the brake actuator improves braking comfort by eliminating rebound vibration in the brake pedal during ABS and other actions. Furthermore, it prevents the impact force from being transmitted to the passenger compartment during a collision, enhancing passive safety. The absence of hydraulic brake lines and fluid eliminates the need for hydraulic oil replacement and leakage, contributing to environmental friendliness. The electromechanical braking system also has no non-recyclable components, resulting in minimal pollution. It allows for the expansion of communication interfaces, enhancing the integration of the braking system with the vehicle's intelligent network. Independent control of the four-wheel brakes enables a higher level of autonomous driving.

[0056] In practical implementation, when the vehicle is braking, the driver presses the brake pedal, and the signal from the pedal sensor on the brake pedal is sent to the central controller. The central controller analyzes the braking intention from the pedal sensor signal and, by combining the vehicle's CAN signal with information such as the current vehicle speed, vehicle motion posture, and real-time road conditions, formulates a reasonable braking force output to the brake controllers 10 of each electromechanical brake caliper, thereby controlling the braking force of each electromechanical brake caliper in real time. When the brake controller 10 receives the braking force command from the central controller, it controls the speed and torque of the motor 4 of the electromechanical brake caliper to realize the service braking and ABS anti-lock braking functions. The braking operation is mainly divided into three modules: the braking intention recognition module, the electromechanical brake caliper module, and the ABS control module.

[0057] The braking intention recognition module includes a pedal sensor and a central controller. When the driver brakes, they press the brake pedal, and the signal changes from the pedal sensor indirectly reflect the driver's braking intention. The process of analyzing the sensor signals is the braking intention recognition process. During vehicle operation, on one hand, the central controller or brake controller 10 can collect signals from the pedal sensor, analyze the signals, make decisions, and allocate braking force. On the other hand, the central controller can collect signals from various sensors on the vehicle body, analyze them to obtain vehicle posture information, and use this information to recognize braking intention. In practice, the vehicle posture information and the pedal sensor signals can also be combined for braking intention recognition.

[0058] The electromechanical brake caliper, controlled by the brake controller 10, coordinates the operation of the motor 4 and the electromagnetic actuator to achieve precise braking force output and brake gap adjustment at the start and end of braking. To achieve precise braking force output, closed-loop control is required, with braking force being a key control physical quantity in the closed-loop feedback. The brake controller 10 can precisely control the speed and output torque of the motor 4 based on driving intentions or signal input from the central controller, generating corresponding braking force and four-wheel braking force distribution in real time. This enables in-loop monitoring / display of the braking torque of the wheel-side electromechanical brake caliper, features brake pad 3 return function, and incorporates a zero-drag torque design. High-performance ceramic carbon brake discs are used, improving the thermal performance of the braking system and supporting the development and matching of more new energy vehicle models.

[0059] The ABS control module, during braking, aims to maximize tire grip and achieve the shortest braking distance. When activated, the braking system corrects the braking force output from the motor 4 of the electromechanical brake caliper, using tire slip ratio as the target control variable. Through a control algorithm, the system optimizes tire slip ratio under the current road surface conditions, maximizing tire grip.

[0060] After the driver presses the brake pedal, the pedal sensor detects braking signals such as pedal acceleration, displacement, and pedal force. The vehicle's central controller receives the braking command signal through the vehicle network and calculates the optimal braking torque required for each wheel in real time by combining other sensor signals under the current vehicle driving status. After receiving the control signal, the brake controller 10 completes the torque and speed response. The driving torque of the four motors 4 of the electromechanical brake caliper is transmitted and amplified through the transmission mechanism 5 and the reduction mechanism 6, and then drives the screw 701 to rotate through the second planetary carrier 608, which unscrews the nut 703 and pushes the piston 8 to make the two brake pads 3 clamp the brake disc 2, thereby generating braking torque. In order to ensure smooth and reliable vehicle braking, the central controller will monitor the feedback information of each electromechanical brake caliper and each sensor in real time and adjust the braking force in a timely manner. In addition, during the braking process, the magnitude or direction of the input current of the motor 4 is controlled to enable the vehicle to activate the ABS function, thereby keeping the vehicle's tires at the maximum adhesion coefficient and achieving the shortest braking distance. When ABS is activated, the braking system corrects the braking force output by the motor 4 of the electromechanical brake caliper by using the tire slip ratio as the target control variable. The control algorithm aims to make the tire have the optimal slip ratio under the current road surface, so that the tire is in the state of maximum adhesion coefficient as much as possible.

[0061] Furthermore, the braking system can be used in conjunction with other additional functional modules to achieve a variety of additional functions.

[0062] The electromechanical brake caliper proposed in this application serves as an actuator for generating braking torque in vehicles. It eliminates intermediate media such as brake fluid / gas in traditional braking systems, converting the driver's braking intention or the communication signals allocated to the braking system by the central controller into analog electrical signals. This allows for the expansion of more communication interfaces, improves the integration of the braking system with the vehicle's intelligent network, and enables independent control of the four-wheel brakes, thereby achieving a higher level of autonomous driving. It also provides component solutions for chassis-by-wire braking. Furthermore, the electromechanical brake caliper proposed in this application uses electrical energy as its power source and replaces the complex piping in traditional braking systems with wires, achieving redundant control of the four-wheel brakes and improving vehicle safety performance and response speed. The electromechanical brake caliper described in this application employs dual motors on both sides for four safety backups, resulting in higher reliability.

[0063] This invention also proposes an electromechanical brake caliper control method, which is used to control the electromechanical brake caliper described in any of the above claims, such as... Figure 5As shown, the electromechanical brake caliper control method includes the following steps: S100: In response to receiving a parking release command, the electromagnetic actuator is controlled to operate, so that the electromagnetic actuator applies a force to the piston 8 in a direction opposite to the brake disc 2. Using the above technical solution, during the parking release process, the electromagnetic actuator drives the piston 8 to return to its original position. This reduces or even eliminates drag force and ensures that the nut 703 and piston 8 are tightly abutted, preventing the nut 703 from rotating relative to the piston 8 and ensuring that the nut 703 can return to its original position smoothly. Furthermore, to ensure that the nut 703 and piston 8 are tightly abutted, the electromechanical brake caliper control method also includes the following step: In response to receiving a parking command, the electromagnetic actuator is controlled to operate, so that the electromagnetic actuator applies a force to the piston 8 in a direction opposite to the brake disc 2. This force can be calibrated according to the structure of the nut 703 and piston 8.

[0064] In practical implementation, the above-mentioned electromechanical brake caliper control method can be executed by a control device, which includes a command receiving module and an electromagnetic actuator control module. The command receiving module is used to receive commands; the electromagnetic actuator control module is used to control the electromagnetic actuator to work in response to the received command to release the parking brake, so that the electromagnetic actuator applies a force to the piston 8 in a direction away from the brake disc 2.

[0065] In some embodiments, the parking controller includes a memory and a processor. The memory stores a computer program, which, when executed by the processor, implements the electromechanical brake caliper control method described above.

[0066] The above embodiments are merely preferred embodiments provided to fully illustrate the present invention, and the scope of protection of the present invention is not limited thereto. Equivalent substitutions or modifications made by those skilled in the art based on the present invention are all within the scope of protection of the present invention. In the description of this specification, the reference to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., means that a specific feature, structure, material, or characteristic associated with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in any suitable manner in one or more embodiments or examples. Furthermore, those skilled in the art can combine and integrate the different embodiments or examples described in this specification.

Claims

1. An electromechanical brake caliper, comprising a housing, a brake disc, and brake pads, characterized in that, It also includes an actuation component and an electromagnetic actuator. The actuation component is disposed in the housing and includes a motor, a transmission structure, a conversion mechanism, and a piston. The power output end of the motor is connected to the power input end of the conversion mechanism through the transmission structure. The conversion mechanism can convert the rotational motion of its power input end into the linear motion of its power output end. The linear motion of the power output end of the conversion mechanism can push the piston to drive the brake pad to press against the brake disc. The electromagnetic actuator is disposed between the housing and the piston. The electromagnetic actuator is used to apply a force away from the brake disc to the piston during the parking and releasing of the electromechanical brake caliper. The conversion mechanism includes a screw and a nut that is threadedly engaged with the screw. The screw is connected to the power output end of the transmission structure, and one end of the nut abuts against the piston.

2. The electromechanical brake caliper according to claim 1, characterized in that, The outer casing is provided with a first mounting hole, the piston slides in the first mounting hole, and a sealing ring is provided between the piston and the first mounting hole.

3. The electromechanical brake caliper according to claim 1, characterized in that, A spring is provided between the brake pad and the housing, and the spring is used to apply a force to the brake pad in a direction away from the brake disc.

4. The electromechanical brake caliper according to claim 1, characterized in that, The electromagnetic actuator includes a permanent magnet and an electromagnetic coil, which are fixedly connected to the housing and the piston, respectively.

5. The electromechanical brake caliper according to claim 1, characterized in that, The actuation assembly includes at least two of the motors.

6. The electromechanical brake caliper according to claim 1, characterized in that, A brake pad is provided on each side of the brake disc, and two actuation components are provided in the housing. One actuation component can drive one brake pad to press against the brake disc, and the other actuation component can drive the other brake pad to press against the brake disc.

7. The electromechanical brake caliper according to claim 1, characterized in that, A brake controller is fixedly connected to the outer casing.

8. The electromechanical brake caliper according to claim 1, characterized in that, The transmission structure includes a transmission mechanism and a reduction mechanism. The power output end of the motor is connected to the power input end of the transmission mechanism, the power output end of the transmission mechanism is connected to the power input end of the reduction mechanism, and the power output end of the reduction mechanism is connected to the power input end of the conversion mechanism. The transmission mechanism is a fixed-axis gear train transmission mechanism, and the reduction mechanism is a two-stage planetary gear reduction mechanism.

9. An electromechanical brake caliper control method, wherein the electromechanical brake caliper control method is used to control the electromechanical brake caliper according to any one of claims 1-8, characterized in that, The electromechanical brake caliper control method includes the following steps: in response to receiving a command to release the parking brake, controlling the electromagnetic actuator to operate so that the electromagnetic actuator applies a force to the piston in a direction opposite to the brake disc; In response to receiving a parking command, the electromagnetic actuator is controlled to operate so that it applies a force to the piston in a direction opposite to that of the brake disc.

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