Electromechanical brake system

Abstract

The invention discloses an electronic mechanical braking system which is characterized in that an ECU PCBA (Printed Circuit Board Assembly) controls a motor to drive a motor gear, the motor gear drives a duplicate gear and drives a large gear to perform secondary gear reduction, a double-row ball bearing is arranged in the duplicate gear, and a gear shaft and a tolerance ring are fixed on a supporting shell and a lower shell of an ECU controller to run stably; the large gear can bear certain axial and radial loads, and the large gear after speed reduction and torque increase drives a lead screw shaft of the planetary roller lead screw through a spline; a plurality of rollers in the planetary roller lead screw convert rotary motion into translational motion to push a nut (integrated with a brake piston) of the lead screw, and enough braking force is provided to push an inner friction plate and an outer friction plate to be precisely attached to a brake disc to achieve service braking. And the ECU PCBA is used for controlling the electromagnet assembly to drive the pawl and the ratchet wheel to be closed and opened, so that starting and releasing of parking are achieved. The EMB transmission efficiency and reliability can be improved, the cost is low, a small-torque motor can be adopted, the vehicle model adaptability is high, and assembling is easy.

Description

Technical Field

[0001] This invention relates to the automotive field, and in particular to an electromechanical braking system. Background Technology

[0002] With the rapid development of electrification and intelligentization in the automotive industry, Level 3 and above autonomous driving electric vehicles are placing higher technical demands on vehicle braking systems. Electro-mechanical braking (EMB) technology, with its rapid response, high-precision control, lightweight design, and intelligent potential, is driving the transformation of automotive braking systems towards electrification, intelligentization, and drive-by-wire. Although EMB systems offer numerous advantages, their transmission mechanisms mostly employ a combination of ball screws, two-stage gears, and planetary gears to coordinate with the motor's output braking force. This type of mechanism is complex, bulky, costly, has generally low transmission efficiency, insufficient fatigue and impact resistance, and high requirements for motor output torque, making it unsuitable for wheel-side layouts and the demands of harsh operating conditions. Summary of the Invention

[0003] The summary of this invention introduces a series of simplified concepts, all of which are simplifications of existing technologies in the field, and will be further explained in detail in the detailed description section. This summary is not intended to limit the key features and essential technical features of the claimed technical solution, nor is it intended to determine the scope of protection of the claimed technical solution.

[0004] The technical problem to be solved by the present invention is to provide an electromechanical braking system that improves transmission efficiency and reliability by improving the layout of the wheel-side structure of automobiles and taking into account factors such as harsh working conditions and cost, has a simple manufacturing process, maintains a compact structure, is compatible with caliper assemblies and low-torque motors, and meets the EMB requirements of different vehicle models.

[0005] To solve the above-mentioned technical problems, the present invention provides an electromechanical braking system, comprising:

[0006] The motor (1) is mounted on the support housing (4), and its output shaft is equipped with a motor gear (9) and a ratchet (8) to provide a power source for the transmission mechanism;

[0007] The motor sealing ring (2) is installed between the support housing (4) and the motor (1) to provide a sealing function;

[0008] Fix the motor (1) to the support housing (4) with fixing bolts (3);

[0009] Support housing (4) serves as the housing assembly supporting the entire transmission mechanism;

[0010] The pawl fixing shaft (5) is fixed at one end to the support housing (4), and the pawl (6) is fitted at the other end with clearance;

[0011] The pawl (6) can rotate around the pawl fixed axis (5) and cooperate with the ratchet (8) to realize the parking function;

[0012] The E-type retaining ring (7) of the pawl fixes the pawl (6) axially to one end of the pawl fixing shaft (5);

[0013] Ratchet (8) is mounted on the motor output shaft and works with pawl (6) to achieve parking function;

[0014] The motor gear (9) is press-fitted onto the motor output shaft to transmit the rotational torque of the motor (1) to the double gear (14);

[0015] The motor position sensor (10) is mounted on the motor output shaft by interference fit, and transmits the motor angle and speed signals to the ECU for motor control and diagnosis.

[0016] The lower housing (11) of the ECU controller is equipped with a PCBA (12) and the upper housing (13) of the ECU controller, and is connected to the support housing (4) by bolts and tolerance rings (18);

[0017] PCBA(12) integrates various hardware components such as chips, connectors, and capacitors to receive data and send instructions;

[0018] The upper housing (13) of the ECU controller is assembled with the lower housing (11) of the ECU controller by applying adhesive to seal the internal hardware components. Connectors are installed on the outside, and a test vent is provided on the housing.

[0019] The double gear (14) is divided into a small tooth part and a large tooth part. The small tooth part is engaged with the large gear (19), and the large tooth part is engaged with the motor gear (9). The rotational torque of the motor gear (9) is transmitted to the large gear (19), and the two-stage reduction is achieved through the transmission ratio of the meshing with the motor gear (9) and the large gear (19).

[0020] Double row ball bearing retaining ring (15) fixes the outer ring of double row ball bearing (16) in the inner hole of double gear (14);

[0021] A double-row ball bearing (16) is connected to the gear shaft (17) and supports the rotation of the double gear (14);

[0022] The gear shaft (17) is fixed on the support housing (4) and is used for the installation and positioning of the double row ball bearing (16) and the double gear (14) assembly;

[0023] The tolerance ring (18) is assembled on the shaft end of the gear shaft (17) for precise installation of the lower housing (11) of the ECU controller and the support housing (4);

[0024] The large gear (19) is installed as a whole with the deep groove ball bearing (20), which transmits the rotational torque of the double gear (14) to the screw shaft of the planetary roller screw (27) and converts it into the linear motion of the screw nut. It also achieves deceleration by meshing with the double gear (14) through a certain reduction ratio.

[0025] A deep groove ball bearing (20) is connected to the support housing (4) to withstand a certain axial impact load and support the large gear (19) to rotate in the support housing (4);

[0026] A C-type retaining ring (21) is used to fix the deep groove ball bearing (20) onto the large gear (19) to prevent the deep groove ball bearing (20) from moving axially.

[0027] E-type retaining ring (22) fixes the screw shaft of the planetary roller screw (27) inside the caliper body (30) to prevent the screw shaft of the planetary roller screw (27) from moving axially.

[0028] A copper bushing (23) is placed between the screw shaft of the planetary roller screw (27) and the caliper body (30) to prevent the screw shaft from hitting the caliper body (30) during rotation and to act as a sliding bearing.

[0029] The O-ring (24) is assembled between the support housing (4) and the caliper body (30) to provide a sealing function;

[0030] Force sensor (25) is used to transmit braking force signals to the ECU in real time;

[0031] The thrust needle roller bearing (26) transmits the braking force from the planetary roller screw (27) to the force sensor (25), and at the same time serves as the carrier for the rotation and bearing of the screw shaft;

[0032] The planetary roller screw (27) can convert the rotational motion transmitted by the reduction mechanism into the linear motion of the screw nut to provide braking force, while also being able to withstand the axial impact from the friction plate.

[0033] The guide pin dust cover (28) prevents foreign objects from entering the inner hole where the guide pin (29) and the caliper body (30) meet, thus affecting the sliding friction;

[0034] Guide pin (29) is used to allow the caliper body (30) to slide smoothly on the caliper bracket (36) during braking;

[0035] The caliper body (30) has an actuator inside that is connected to a reduction mechanism, and is equipped with an inner friction plate (33) and an outer friction plate (34) for braking;

[0036] A rectangular sealing ring (31) prevents the grease from leaking out of the actuator and prevents foreign objects from entering the caliper body (30);

[0037] Piston dust cover (32) is used to prevent foreign objects of various sizes from entering the caliper body (30);

[0038] The internal friction pad (33) is subjected to the thrust of the piston integrated on the nut of the planetary roller screw (27) during braking, and fits tightly with the brake disc to achieve vehicle deceleration or stopping.

[0039] The outer friction pad (34) generates a reaction force during braking, which acts on the caliper body (30), causing it and the inner friction pad (33) to come into close contact with the brake disc to achieve vehicle deceleration or stopping.

[0040] Spring plate (35) is set at both ends of inner friction plate (33) and outer friction plate (34) to fix the friction plate, and is fixed on caliper bracket (36) to ensure that the friction plate and brake disc are in close contact during braking for smooth braking;

[0041] Caliper bracket (36) is used to fix and support various braking components to ensure stable operation of the braking system;

[0042] Keyway gasket (37) is used to seal the keyway through which the flat key (39) runs;

[0043] Keyway cover (38) to prevent various foreign objects from entering the keyway;

[0044] A flat key (39) is installed on the nut surface of the planetary roller screw (27) and engages with the keyway on the caliper body (30) to achieve smooth translation of the screw nut during operation.

[0045] Keyway bolts (40) are used to fix the keyway cover (38) to the caliper body (30);

[0046] The electromagnet assembly (41) works with the ratchet (8) and pawl (6) as an electromagnetic actuator to perform the parking function;

[0047] A cotter pin (42) is used to connect the electromagnet assembly (41) to the pawl (6);

[0048] The electromagnet assembly (41) is fixed to the support housing (4) with an internal hex bolt (43).

[0049] Preferably, the electromechanical braking system is further improved by including: the inner ring of the double-row ball bearing (16) is directly pressed into the corresponding outer diameter surface of the gear shaft (17) to form an interference fit, the outer ring of the double-row ball bearing (16) is clearance-fitted with the inner hole of the double gear (14), and is fixed by the double-row ball bearing retaining ring (15).

[0050] Preferably, the electromechanical braking system is further improved by including: the side of the large gear (19) is press-fitted into the inner ring of the deep groove ball bearing (20) and axially fixed by a C-type retaining ring (21); the outer ring of the deep groove ball bearing (20) is pressed into the support housing (4) and fixed by a riveting process.

[0051] Preferably, the electromechanical braking system is further improved by including: an internal spline on the end of the planetary roller screw (27) shaft, which engages with the external spline on the corresponding side of the large gear (19).

[0052] Preferably, the electromechanical braking system is further improved by including: a retaining ring groove at the end of the planetary roller screw (27) for installing an E-type retaining ring (22) against the outer wall of the caliper body (30); a sliding copper sleeve (23) is fitted between the outer diameter surface of the screw shaft end and the inner hole of the caliper body (30); a groove is opened at the corresponding position on the outer diameter surface of the screw nut; a flat key (39) is placed in the groove; the flat key (39) reciprocates against the keyway in the inner hole of the caliper body (30) to prevent the planetary roller screw (27) nut from rotating. The flat key (39) is easily assembled onto the planetary roller screw (27) nut through the keyway opening on the caliper body (30); a sealing component is provided at the keyway opening.

[0053] Preferably, the electromechanical braking system is further improved by including: the inner hole of the thrust needle roller bearing (26) passes through the lead screw shaft, one side gasket is in close contact with the flange surface of the lead screw shaft, and the other side gasket is in close contact with the force-bearing surface of the force sensor (25).

[0054] Preferably, the electromechanical braking system further improves upon the above, and further includes: the planetary roller screw (27) nut and the brake piston are assembled together by interference fit, and a spherical surface is provided on the inner center surface of the piston near the screw shaft to correspond to the screw shaft end face at the initial position, and the return stop is determined by contact with the screw shaft end and used for the calibration of the zero position of the motor (1).

[0055] Preferably, the electromechanical braking system is further improved by including: the motor gear (9) transmitting the motor torque to the double gear (14), and then to the large gear (19) to achieve two-stage speed reduction and torque increase. The large gear (19) is connected to the lead screw shaft through a spline and drives the lead screw shaft to rotate. The rotational motion of the lead screw shaft is synchronously converted into the translational motion of the lead screw nut to drive the brake piston, which is assembled with the lead screw nut, to drive the inner friction plate (33) and the outer friction plate (34) to provide braking force.

[0056] Preferably, the electromechanical braking system is further improved by including: the caliper body (30) has a built-in planetary roller screw (27), a thrust needle bearing (26), a force sensor (25), and a flat key (39) to realize the output braking force, and is fixedly mounted on the caliper bracket (36) by the guide pin (29). The caliper bracket (36) is directly mounted on the wheel side of the car chassis through two mounting holes to support the system components.

[0057] Preferably, the electromechanical braking system is further improved by including: the parking function is implemented by the parking mechanism, the parking mechanism is provided with an electromagnet assembly (41) installed on the support housing (4), the ratchet (8) is fixed on the output shaft of the motor (1), one end of the corresponding pawl (6) is fixed to the pawl E-type retaining ring (7) through the pawl fixing shaft (5) installed on the support housing (4), and the other end of the pawl (6) is connected to the electromagnet assembly (41) to form a closing and opening mechanism for the ratchet (8), thereby realizing the opening and release of the parking.

[0058] Preferably, the electromechanical braking system is further improved by including: the inner hole of the double gear (14) is embedded with a double row ball bearing (16) and the outer ring of the bearing is fixed by a double row ball bearing retainer (15); the inner hole of the double row ball bearing (16) is press-fitted onto the gear shaft (17); the gear shaft (17) is fixed onto the support housing (4); a small hole is opened at the bottom end of the gear shaft (17) corresponding to the support housing (4) to facilitate press-fit ventilation; and a tolerance ring (18) is provided at the end of the gear shaft (17) that is assembled with the ECU housing for centering.

[0059] Preferably, the electromechanical braking system is further improved by including: a groove on the outer end face of the force sensor (25) and a protrusion at the mounting point of the caliper body (30) to prevent rotation; the inner hole of the force sensor (25) is mounted between the thrust needle bearing (26) and the wall of the caliper body (30) through the planetary roller screw (27); the wiring harness of the force sensor (25) passes through the opening of the caliper body (30) and is connected to the ECU; and a sealing mechanism is provided between the wiring harness and the hole of the caliper body (30).

[0060] Preferably, the electromechanical braking system is further improved by using extreme pressure grease for the planetary roller screw (27) and the thrust needle roller bearing (26).

[0061] Preferably, the electromechanical braking system is further improved by including: the motor (1) is fastened and sealed to the support housing (4) by bolts and sealing rings; the ratchet (8) mounted on the output shaft of the motor (1) cooperates with the pawl to realize the parking function; the motor gear (9) cooperates with the double gear (14) to realize speed reduction and torque increase; a motor position sensor (10) is set at the end of the output shaft of the motor (1) to output signals to the surrounding chips; and the three-phase pins of the motor (1) are directly inserted into the corresponding slots of the PCBA (12).

[0062] The working principle of this invention is as follows:

[0063] When the vehicle is braking, the pedal displacement sensor and wheel speed sensor transmit signals to the ECU PCBA (12) of the EMB through the vehicle VCU. The ECU PCBA (12) controls the motor (1) to drive the motor gear (9) to rotate. The motor gear (9) drives the double gear (14), which drives the large gear (19) to perform two-stage gear reduction. The double gear (14) has a built-in double row ball bearing (16), gear shaft (17) and tolerance ring (18) fixed on the support housing (4) and the lower housing (11) of the ECU controller to run smoothly and can withstand certain axial and radial loads. After the reduction and torque increase, the large gear (19) drives the screw shaft of the planetary roller screw (27) through the spline. Multiple rollers within the planetary roller screw (27) convert rotational motion into translational motion, pushing the nut of the screw (integrated with the brake piston) to provide sufficient braking force to push the inner friction plate (33) and outer friction plate (34) to precisely engage with the brake disc to achieve vehicle braking. Compared to commonly used ball screws, the planetary roller screw (27) has features such as ultra-small lead, good operating efficiency, ultra-high rated dynamic and static loads, and the ability to withstand impacts and vibrations from all directions. It can achieve a small torque motor and a high gear reduction ratio to output a large axial force, meeting the large braking force requirements of the EMB. The thrust needle bearing (26) located between the planetary roller screw (27) and the caliper body (30) transmits the braking force during operation to the force sensor (25) in a timely manner, and then feeds it back to the ECU PCBA (12) through the force sensor (25). A flat key (39) is provided on the lead screw nut to engage with the keyway in the caliper body (30) to prevent the lead screw nut from rotating during operation. At the same time, a spherical surface is designed at the center of the brake piston integrated with the lead screw nut to collide with the lead screw shaft when the lead screw nut returns to position the initial position of the braking cycle. It can also be used as the zeroing position of the motor (1) for calibration. A motor position sensor (10) is provided at the motor output shaft end to transmit the motor angle and speed signals to the ECU PCBA (12) for motor control and diagnosis. When the vehicle is under parking brake, the vehicle master controller controls the electromagnet assembly (41) through the ECU PCBA (12) to drive the pawl (6) and ratchet (8) to close and open, thereby opening and closing the parking brake.

[0064] The above-described structure and working principle of the present invention can achieve at least the following technical effects;

[0065] 1) The overall electromechanical braking system has a compact structure and is compatible with both the front and rear wheels of a car. The product assembly line can be completely collinear, and it has a high degree of adaptability to the boundaries of the whole vehicle.

[0066] 2) The planetary roller screw and two-stage gear combination is used as the transmission mechanism. The planetary roller screw has the advantages of ultra-small lead, good operating efficiency, ultra-high rated dynamic load and rated static load, and resistance to impact and vibration compared with the ball screw. The structure and cost are significantly better than the ball screw and two-stage gear + planetary gear combination, which can reduce the motor torque while still meeting the design requirements.

[0067] 3) The planetary roller screw and thrust needle roller bearing are installed as one unit and fitted into the caliper body through an E-type retaining ring and a copper sleeve. The planetary screw converts the rotational motion of the screw shaft into the translational motion of the screw nut to provide braking force. At the same time, the planetary screw and thrust needle roller bearing can withstand the axial impact from the brake disc and friction plate together. The installation is simple and convenient.

[0068] 4) A two-stage gear reduction mechanism is adopted. The high-speed motor gear reduces the speed of the large gear through the idler gear (double gear). The large gear drives the planetary roller screw through the spline, which avoids the resonance and fatigue wear problems caused by the high speed of the planetary roller screw.

[0069] 5) A double-row ball bearing is installed between the gear shaft and the double gear, which can play a role in centering, balancing the load, and reducing noise.

[0070] 6) A stainless steel tolerance ring is provided at the end of the gear shaft for mounting the ECU housing and the support housing. It serves to center the gear, facilitate assembly, improve vibration and noise, increase load capacity, optimize tolerances, and compensate for thermal expansion differences.

[0071] 7) The ECU controller housing is integrated with the PCBA and has integrated connectors. At the same time, it has slots for easy assembly with the motor three-phase pins and parking electromagnet pins.

[0072] 8) The nut surface of the planetary roller screw is provided with a flat key that matches the corresponding keyway in the inner hole of the caliper body. This prevents the screw nut from rotating during operation and allows for smooth translation for braking.

[0073] 9) The brake piston, which is integrated with the lead screw and nut, is designed with a spherical surface at its center. This surface is used to locate the initial position of the braking cycle by colliding with the lead screw shaft when the lead screw and nut return to their original position. It can also be used as the zeroing position of the motor for calibration.

[0074] 10) It adopts a permanent magnet motor, which can ensure reliable operation in harsh environments such as cold, heat, humidity, and electronic interference.

[0075] 11) The ratchet and pawl parking structure uses a bistable electromagnetic actuator to perform the parking function. The holding force is kept stable, the push rod push force runs smoothly, and no energy is consumed in the holding state, which has high stability.

[0076] 12) A force sensor is installed between the thrust needle roller bearing and the inner wall of the caliper body and connected to the wheel end controller. It is used to sense the clamping force of the wheel end caliper, measure the clamping force of the caliper assembly, obtain clamping force data, and transmit the clamping force data to the central controller through the wheel end controller, so as to make the clamping force control more precise and for diagnostic purposes. Attached Figure Description

[0077] The accompanying drawings are intended to illustrate the general characteristics of the methods, structures, and / or materials used in specific exemplary embodiments of the invention, supplementing the description in the specification. However, the drawings are schematic diagrams not drawn to scale and may not accurately reflect the precise structural or performance characteristics of any of the given embodiments. The drawings should not be construed as limiting or restricting the range of numerical values ​​or properties covered by exemplary embodiments of the invention. The invention will now be described in further detail with reference to the accompanying drawings and specific embodiments:

[0078] Figure 1 This is a schematic cross-sectional view of the electromechanical braking system of the present invention. Figure 1 .

[0079] Figure 2 This is a schematic cross-sectional view of the electromechanical braking system of the present invention. Figure 2 .

[0080] Figure 3 This is a schematic cross-sectional view of the electromechanical braking system of the present invention. Figure 3

[0081] Explanation of reference numerals in the attached figures:

[0082] Motor 1;

[0083] Motor sealing ring 2;

[0084] Fixing bolt 3;

[0085] Support shell 4;

[0086] Pawl fixing shaft 5;

[0087] 6 pawls;

[0088] Pawl E-type retaining ring 7;

[0089] Ratchet 8;

[0090] Motor gear 9;

[0091] Motor position sensor 10;

[0092] ECU controller lower housing 11;

[0093] PCBA 12;

[0094] ECU controller upper housing 13;

[0095] Double gear 14;

[0096] Double row ball bearing retaining ring 15;

[0097] Double row ball bearing 16;

[0098] Gear shaft 17;

[0099] Tolerance ring 18;

[0100] Large Gear 19;

[0101] Deep groove ball bearing 20;

[0102] C-type clasp 21;

[0103] E-type retaining ring 22;

[0104] Copper sleeve 23;

[0105] O-ring 24;

[0106] Force sensor 25;

[0107] Thrust needle roller bearing 26;

[0108] Planetary roller screw 27;

[0109] Guide pin dust cover 28;

[0110] Guide pin 29;

[0111] Caliper body 30;

[0112] Rectangular sealing ring 31;

[0113] Piston dust cover 32;

[0114] Internal friction plate 33;

[0115] External friction plate 34;

[0116] Spring sheet 35;

[0117] Caliper bracket 36;

[0118] Keyway gasket 37;

[0119] Keyway cover 38;

[0120] Flat key 39;

[0121] 40 keyway bolts;

[0122] Electromagnet assembly 41;

[0123] Cotter pin 42;

[0124] 43mm socket head cap screw; Detailed Implementation

[0125] The following specific embodiments illustrate the implementation of the present invention. Those skilled in the art can fully understand other advantages and technical effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through different specific embodiments, and various details in this specification can also be applied based on different viewpoints, with various modifications or changes made without departing from the overall design concept of the invention. It should be noted that, in the absence of conflict, the following embodiments and features in the embodiments can be combined with each other. The following exemplary embodiments of the present invention can be implemented in many different forms and should not be construed as being limited to the specific embodiments set forth herein. It should be understood that these embodiments are provided so that the disclosure of the present invention is thorough and complete, and that the technical solutions of these exemplary embodiments are fully conveyed to those skilled in the art. It should be understood that when an element is referred to as "connected" or "combined" to another element, the element can be directly connected or combined to the other element, or there may be intermediate elements. The difference is that when an element is referred to as "directly connected" or "directly combined" to another element, there are no intermediate elements. Throughout the drawings, the same reference numerals always denote the same elements. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items. Other terms used to describe the relationship between elements or layers should be interpreted in the same way (e.g., “between” and “directly between”, “adjacent to” and “directly adjacent to”, “on” and “directly on”, etc.).

[0126] Example

[0127] like Figures 1 to 3 As shown, the present invention provides an electromechanical braking system, comprising:

[0128] The motor (1) is mounted on the support housing (4), and its output shaft is equipped with a motor gear (9) and a ratchet (8) to provide a power source for the transmission mechanism;

[0129] The motor sealing ring (2) is installed between the support housing (4) and the motor (1) to provide a sealing function;

[0130] Fix the motor (1) to the support housing (4) with fixing bolts (3);

[0131] Support housing (4) serves as the housing assembly supporting the entire transmission mechanism;

[0132] The pawl fixing shaft (5) is fixed at one end to the support housing (4), and the pawl (6) is fitted at the other end with clearance;

[0133] The pawl (6) can rotate around the pawl fixed axis (5) and cooperate with the ratchet (8) to realize the parking function;

[0134] The E-type retaining ring (7) of the pawl fixes the pawl (6) axially to one end of the pawl fixing shaft (5);

[0135] Ratchet (8) is mounted on the motor output shaft and works with pawl (6) to achieve parking function;

[0136] The motor gear (9) is press-fitted onto the motor output shaft to transmit the rotational torque of the motor (1) to the double gear (14);

[0137] The motor position sensor (10) is mounted on the motor output shaft by interference fit, and transmits the motor angle and speed signals to the ECU for motor control and diagnosis.

[0138] The lower housing (11) of the ECU controller is equipped with a PCBA (12) and the upper housing (13) of the ECU controller, and is connected to the support housing (4) by bolts and tolerance rings (18);

[0139] PCBA(12) integrates various hardware components such as chips, connectors, and capacitors to receive data and send instructions;

[0140] The upper housing (13) of the ECU controller is assembled with the lower housing (11) of the ECU controller by applying adhesive to seal the internal hardware components. Connectors are installed on the outside, and a test vent is provided on the housing.

[0141] The double gear (14) is divided into a small tooth part and a large tooth part. The small tooth part is engaged with the large gear (19), and the large tooth part is engaged with the motor gear (9). The rotational torque of the motor gear (9) is transmitted to the large gear (19), and the two-stage reduction is achieved through the transmission ratio of the meshing with the motor gear (9) and the large gear (19).

[0142] Double row ball bearing retaining ring (15) fixes the outer ring of double row ball bearing (16) in the inner hole of double gear (14);

[0143] A double-row ball bearing (16) is connected to the gear shaft (17) and supports the rotation of the double gear (14);

[0144] The gear shaft (17) is fixed on the support housing (4) and is used for the installation and positioning of the double row ball bearing (16) and the double gear (14) assembly;

[0145] The tolerance ring (18) is assembled on the shaft end of the gear shaft (17) for precise installation of the lower housing (11) of the ECU controller and the support housing (4);

[0146] The large gear (19) is installed as a whole with the deep groove ball bearing (20), which transmits the rotational torque of the double gear (14) to the screw shaft of the planetary roller screw (27) and converts it into the linear motion of the screw nut. It also achieves deceleration by meshing with the double gear (14) through a certain reduction ratio.

[0147] A deep groove ball bearing (20) is connected to the support housing (4) to withstand a certain axial impact load and support the large gear (19) to rotate in the support housing (4);

[0148] A C-type retaining ring (21) is used to fix the deep groove ball bearing (20) onto the large gear (19) to prevent the deep groove ball bearing (20) from moving axially.

[0149] E-type retaining ring (22) fixes the screw shaft of the planetary roller screw (27) inside the caliper body (30) to prevent the screw shaft of the planetary roller screw (27) from moving axially.

[0150] A copper bushing (23) is placed between the screw shaft of the planetary roller screw (27) and the caliper body (30) to prevent the screw shaft from hitting the caliper body (30) during rotation and to act as a sliding bearing.

[0151] The O-ring (24) is assembled between the support housing (4) and the caliper body (30) to provide a sealing function;

[0152] Force sensor (25) is used to transmit braking force signals to the ECU in real time;

[0153] The thrust needle roller bearing (26) transmits the braking force from the planetary roller screw (27) to the force sensor (25), and at the same time serves as the carrier for the rotation and bearing of the screw shaft;

[0154] The planetary roller screw (27) can convert the rotational motion transmitted by the reduction mechanism into the linear motion of the screw nut to provide braking force, while also being able to withstand the axial impact from the friction plate.

[0155] The guide pin dust cover (28) prevents foreign objects from entering the inner hole where the guide pin (29) and the caliper body (30) meet, thus affecting the sliding friction;

[0156] Guide pin (29) is used to allow the caliper body (30) to slide smoothly on the caliper bracket (36) during braking;

[0157] The caliper body (30) has an actuator inside that is connected to a reduction mechanism, and is equipped with an inner friction plate (33) and an outer friction plate (34) for braking;

[0158] A rectangular sealing ring (31) prevents the grease from leaking out of the actuator and prevents foreign objects from entering the caliper body (30);

[0159] Piston dust cover (32) is used to prevent foreign objects of various sizes from entering the caliper body (30);

[0160] The internal friction pad (33) is subjected to the thrust of the piston integrated on the nut of the planetary roller screw (27) during braking, and fits tightly with the brake disc to achieve vehicle deceleration or stopping.

[0161] The outer friction pad (34) generates a reaction force during braking, which acts on the caliper body (30), causing it and the inner friction pad (33) to come into close contact with the brake disc to achieve vehicle deceleration or stopping.

[0162] Spring plate (35) is set at both ends of inner friction plate (33) and outer friction plate (34) to fix the friction plate, and is fixed on caliper bracket (36) to ensure that the friction plate and brake disc are in close contact during braking for smooth braking;

[0163] Caliper bracket (36) is used to fix and support various braking components to ensure stable operation of the braking system;

[0164] Keyway gasket (37) is used to seal the keyway through which the flat key (39) runs;

[0165] Keyway cover (38) to prevent various foreign objects from entering the keyway;

[0166] A flat key (39) is installed on the nut surface of the planetary roller screw (27) and engages with the keyway on the caliper body (30) to achieve smooth translation of the screw nut during operation.

[0167] Keyway bolts (40) are used to fix the keyway cover (38) to the caliper body (30);

[0168] The electromagnet assembly (41) works with the ratchet (8) and pawl (6) as an electromagnetic actuator to perform the parking function;

[0169] A cotter pin (42) is used to connect the electromagnet assembly (41) and the pawl (6);

[0170] The electromagnet assembly (41) is fixed to the support housing (4) with an internal hex bolt (43).

[0171] Preferably, the electromechanical braking system is further improved by including: the inner ring of the double-row ball bearing (16) is directly pressed into the corresponding outer diameter surface of the gear shaft (17) to form an interference fit, the outer ring of the double-row ball bearing (16) is clearance-fitted with the inner hole of the double gear (14), and is fixed by the double-row ball bearing retaining ring (15).

[0172] Preferably, the electromechanical braking system is further improved by including: the side of the large gear (19) is press-fitted into the inner ring of the deep groove ball bearing (20) and axially fixed by a C-type retaining ring (21); the outer ring of the deep groove ball bearing (20) is pressed into the support housing (4) and fixed by a riveting process.

[0173] Preferably, the electromechanical braking system is further improved by including: an internal spline on the end of the planetary roller screw (27) shaft, which engages with the external spline on the corresponding side of the large gear (19).

[0174] Preferably, the electromechanical braking system is further improved by including: a retaining ring groove at the end of the planetary roller screw (27) for installing an E-type retaining ring (22) against the outer wall of the caliper body (30); a sliding copper sleeve (23) is fitted between the outer diameter surface of the screw shaft end and the inner hole of the caliper body (30); a groove is opened at the corresponding position on the outer diameter surface of the screw nut; a flat key (39) is placed in the groove; the flat key (39) reciprocates against the keyway in the inner hole of the caliper body (30) to prevent the planetary roller screw (27) nut from rotating. The flat key (39) is easily assembled onto the planetary roller screw (27) nut through the keyway opening on the caliper body (30); a sealing component is provided at the keyway opening.

[0175] Preferably, the electromechanical braking system is further improved by including: the inner hole of the thrust needle roller bearing (26) passes through the lead screw shaft, one side gasket is in close contact with the flange surface of the lead screw shaft, and the other side gasket is in close contact with the force-bearing surface of the force sensor (25).

[0176] Preferably, the electromechanical braking system further improves upon the above, and further includes: the planetary roller screw (27) nut and the brake piston are assembled together by interference fit, and a spherical surface is provided on the inner center surface of the piston near the screw shaft to correspond to the screw shaft end face at the initial position, and the return stop is determined by contact with the screw shaft end and used for the calibration of the zero position of the motor (1).

[0177] Preferably, the electromechanical braking system is further improved by including: the motor gear (9) transmitting the motor torque to the double gear (14), and then to the large gear (19) to achieve two-stage speed reduction and torque increase. The large gear (19) is connected to the lead screw shaft through a spline and drives the lead screw shaft to rotate. The rotational motion of the lead screw shaft is synchronously converted into the translational motion of the lead screw nut to drive the brake piston, which is assembled with the lead screw nut, to drive the inner friction plate (33) and the outer friction plate (34) to provide braking force.

[0178] Preferably, the electromechanical braking system is further improved by including: the caliper body (30) has a built-in planetary roller screw (27), a thrust needle bearing (26), a force sensor (25), and a flat key (39) to realize the output braking force, and is fixedly mounted on the caliper bracket (36) by the guide pin (29). The caliper bracket (36) is directly mounted on the wheel side of the car chassis through two mounting holes to support the system components.

[0179] Preferably, the electromechanical braking system is further improved by including: the parking function is implemented by the parking mechanism, the parking mechanism is provided with an electromagnet assembly (41) installed on the support housing (4), the ratchet (8) is fixed on the output shaft of the motor (1), one end of the corresponding pawl (6) is fixed to the pawl E-type retaining ring (7) through the pawl fixing shaft (5) installed on the support housing (4), and the other end of the pawl (6) is connected to the electromagnet assembly (41) to form a closing and opening mechanism for the ratchet (8), thereby realizing the opening and release of the parking.

[0180] Preferably, the electromechanical braking system is further improved by including: the inner hole of the double gear (14) is embedded with a double row ball bearing (16) and the outer ring of the bearing is fixed by a double row ball bearing retainer (15); the inner hole of the double row ball bearing (16) is press-fitted onto the gear shaft (17); the gear shaft (17) is fixed onto the support housing (4); a small hole is opened at the bottom end of the gear shaft (17) corresponding to the support housing (4) to facilitate press-fit ventilation; and a tolerance ring (18) is provided at the end of the gear shaft (17) that is assembled with the ECU housing for centering.

[0181] Preferably, the electromechanical braking system is further improved by including: a groove on the outer end face of the force sensor (25) and a protrusion at the mounting point of the caliper body (30) to prevent rotation; the inner hole of the force sensor (25) is mounted between the thrust needle bearing (26) and the wall of the caliper body (30) through the planetary roller screw (27); the wiring harness of the force sensor (25) passes through the opening of the caliper body (30) and is connected to the ECU; and a sealing mechanism is provided between the wiring harness and the hole of the caliper body (30).

[0182] Preferably, the electromechanical braking system is further improved by using extreme pressure grease for the planetary roller screw (27) and the thrust needle roller bearing (26).

[0183] Preferably, the electromechanical braking system is further improved by including: the motor (1) is fastened and sealed to the support housing (4) by bolts and sealing rings; the ratchet (8) mounted on the output shaft of the motor (1) cooperates with the pawl to realize the parking function; the motor gear (9) cooperates with the double gear (14) to realize speed reduction and torque increase; a motor position sensor (10) is set at the end of the output shaft of the motor (1) to output signals to the surrounding chips; and the three-phase pins of the motor (1) are directly inserted into the corresponding slots of the PCBA (12).

[0184] Unless otherwise defined, all terms used herein (including technical and scientific terms) shall have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. It will also be understood that, unless expressly defined herein, terms such as those defined in a general dictionary shall be interpreted as having the meaning consistent with their meaning in the relevant field context, and not as having an idealized or overly formal meaning.

[0185] The present invention has been described in detail above through specific embodiments and examples, but these are not intended to limit the invention. Many modifications and improvements can be made by those skilled in the art without departing from the principles of the invention, and these should also be considered within the scope of protection of the present invention.

Claims

1. An electromechanical braking system, characterized in that, include: The motor (1) is mounted on the support housing (4), and its output shaft is equipped with a motor gear (9) and a ratchet (8) to provide a power source for the transmission mechanism; The motor sealing ring (2) is installed between the support housing (4) and the motor (1) to provide a sealing function; Fix the motor (1) to the support housing (4) with fixing bolts (3); Support housing (4) serves as the housing assembly supporting the entire transmission mechanism; The pawl fixing shaft (5) is fixed at one end to the support housing (4), and the pawl (6) is fitted at the other end with clearance; The pawl (6) can rotate around the pawl fixed axis (5) and cooperate with the ratchet (8) to realize the parking function; The E-type retaining ring (7) of the pawl fixes the pawl (6) axially to one end of the pawl fixing shaft (5); Ratchet (8) is mounted on the motor output shaft and works with pawl (6) to achieve parking function; The motor gear (9) is press-fitted onto the motor output shaft to transmit the rotational torque of the motor (1) to the double gear (14); The motor position sensor (10) is mounted on the motor output shaft by interference fit, and transmits the motor angle and speed signals to the ECU for motor control and diagnosis. The lower housing (11) of the ECU controller is equipped with a PCBA (12) and the upper housing (13) of the ECU controller, and is connected to the support housing (4) by bolts and tolerance rings (18); PCBA(12) integrates various hardware components such as chips, connectors, and capacitors to receive data and send instructions; The upper housing (13) of the ECU controller is assembled with the lower housing (11) of the ECU controller by applying adhesive to seal the internal hardware components. Connectors are installed on the outside, and a test vent is provided on the housing. The double gear (14) is divided into a small tooth part and a large tooth part. The small tooth part is engaged with the large gear (19), and the large tooth part is engaged with the motor gear (9). The rotational torque of the motor gear (9) is transmitted to the large gear (19), and the two-stage reduction is achieved through the transmission ratio of the meshing with the motor gear (9) and the large gear (19). Double row ball bearing retaining ring (15) fixes the outer ring of double row ball bearing (16) in the inner hole of double gear (14); A double-row ball bearing (16) is connected to the gear shaft (17) and supports the rotation of the double gear (14); The gear shaft (17) is fixed on the support housing (4) and is used for the installation and positioning of the double row ball bearing (16) and the double gear (14) assembly; The tolerance ring (18) is assembled on the shaft end of the gear shaft (17) for precise installation of the lower housing (11) of the ECU controller and the support housing (4); The large gear (19) is installed as a whole with the deep groove ball bearing (20), which transmits the rotational torque of the double gear (14) to the screw shaft of the planetary roller screw (27) and converts it into the linear motion of the screw nut. It also achieves deceleration by meshing with the double gear (14) through a certain reduction ratio. A deep groove ball bearing (20) is connected to the support housing (4) to withstand a certain axial impact load and support the large gear (19) to rotate in the support housing (4); A C-type retaining ring (21) is used to fix the deep groove ball bearing (20) onto the large gear (19) to prevent the deep groove ball bearing (20) from moving axially. E-type retaining ring (22) fixes the screw shaft of the planetary roller screw (27) inside the caliper body (30) to prevent the screw shaft of the planetary roller screw (27) from moving axially. A copper sleeve (23) is set between the screw shaft of the planetary roller screw (27) and the caliper body (30) to prevent the screw shaft from hitting the caliper body (30) during rotation and to play a sliding role. The O-ring (24) is assembled between the support housing (4) and the caliper body (30) to provide a sealing function; Force sensor (25) is used to transmit braking force signals to the ECU in real time; The thrust needle roller bearing (26) transmits the braking force from the planetary roller screw (27) to the force sensor (25), and at the same time serves as the carrier for the rotation and bearing of the screw shaft; The planetary roller screw (27) can convert the rotational motion transmitted by the reduction mechanism into the linear motion of the screw nut to provide braking force, while also being able to withstand the axial impact from the friction plate. The guide pin dust cover (28) prevents foreign objects from entering the inner hole where the guide pin (29) and the caliper body (30) meet, thus affecting the sliding friction; Guide pin (29) is used to allow the caliper body (30) to slide smoothly on the caliper bracket (36) during braking; The caliper body (30) has an actuator inside that is connected to a reduction mechanism, and is equipped with an inner friction plate (33) and an outer friction plate (34) for braking; A rectangular sealing ring (31) prevents the grease from leaking out of the actuator and prevents foreign objects from entering the caliper body (30); Piston dust cover (32) is used to prevent foreign objects of various sizes from entering the caliper body (30); The internal friction pad (33) is subjected to the thrust of the piston integrated on the nut of the planetary roller screw (27) during braking, and fits tightly with the brake disc to achieve vehicle deceleration or stopping. The outer friction pad (34) generates a reaction force during braking, which acts on the caliper body (30), causing it and the inner friction pad (33) to come into close contact with the brake disc to achieve vehicle deceleration or stopping. Spring plates (35) are set at both ends of the inner friction plate (33) and the outer friction plate (34) to fix the friction plates, and are fixed on the caliper bracket (36) to ensure that the friction plates and the brake disc are in close contact during braking for smooth braking. Caliper bracket (36) is used to fix and support various braking components to ensure stable operation of the braking system; Keyway gasket (37) is used to seal the keyway through which the flat key (39) runs; Keyway cover (38) to prevent various foreign objects from entering the keyway; A flat key (39) is installed on the nut surface of the planetary roller screw (27) and engages with the keyway on the caliper body (30) to achieve smooth translation of the screw nut during operation. Keyway bolts (40) are used to fix the keyway cover (38) to the caliper body (30); The electromagnet assembly (41) works with the ratchet (8) and pawl (6) as an electromagnetic actuator to perform the parking function; A cotter pin (42) is used to connect the electromagnet assembly (41) to the pawl (6); The electromagnet assembly (41) is fixed to the support housing (4) with an internal hex bolt (43).

2. The electromechanical braking system as described in claim 1, characterized in that, Also includes: The inner ring of the double-row ball bearing (16) is directly pressed into the corresponding outer diameter surface of the gear shaft (17) to form an interference fit, and the outer ring of the double-row ball bearing (16) is clearance-fitted with the inner hole of the double gear (14) and fixed by the double-row ball bearing retaining ring (15).

3. The electromechanical braking system as described in claim 1, characterized in that, Also includes: The large gear (19) is press-fitted into the inner ring of the deep groove ball bearing (20) and axially fixed by a C-type retaining ring (21). The outer ring of the deep groove ball bearing (20) is pressed into the support housing (4) and fixed by a riveting process.

4. The electromechanical braking system as described in claim 1, characterized in that, Also includes: The planetary roller screw (27) has an internal spline at the end of the screw shaft, which engages with the external spline on the corresponding side of the large gear (19).

5. The electromechanical braking system as described in claim 1, characterized in that, Also includes: The planetary roller screw (27) has a retaining ring groove at its shaft end for mounting an E-type retaining ring (22) against the outer wall of the caliper body (30). A sliding copper sleeve (23) is fitted between the outer diameter surface of the screw shaft end and the inner hole of the caliper body (30). A groove is opened at the corresponding position on the outer diameter surface of the screw nut, and a flat key (39) is placed in the groove. The flat key (39) reciprocates against the keyway in the inner hole of the caliper body (30) to prevent the planetary roller screw (27) nut from rotating. The flat key (39) is easily assembled onto the planetary roller screw (27) nut through the keyway opening on the caliper body (30), and a sealing component is provided at the keyway opening.

6. The electromechanical braking system as described in claim 1, characterized in that, Also includes: The inner hole of the thrust needle roller bearing (26) passes through the lead screw shaft, with one side gasket tightly against the flange surface of the lead screw shaft and the other side gasket tightly against the force-bearing surface of the force sensor (25).

7. The electromechanical braking system as described in claim 1, characterized in that, Also includes: The planetary roller screw (27) nut and the brake piston are assembled together with an interference fit. A spherical surface is set on the inner center surface of the piston near the screw shaft to correspond to the screw shaft end face at the initial position. The return stop is determined by contact with the screw shaft end and used for the calibration of the zero position of the motor (1).

8. The electromechanical braking system as described in claim 1, characterized in that, Also includes: The motor gear (9) transmits the motor torque to the double gear (14), and then to the large gear (19) to achieve two-stage speed reduction and torque increase. The large gear (19) is connected to the lead screw shaft through a spline and drives the lead screw shaft to rotate. The rotational motion of the lead screw shaft is synchronously converted into the translational motion of the lead screw nut, which drives the brake piston assembled with the lead screw nut to drive the inner friction plate (33) and the outer friction plate (34) to provide braking force.

9. The electromechanical braking system as described in claim 1, characterized in that, Also includes: The caliper body (30) has a built-in planetary roller screw (27), thrust needle bearing (26), force sensor (25), and flat key (39) to output braking force. It is fixedly mounted on the caliper bracket (36) through guide pin (29). The caliper bracket (36) is directly mounted on the wheel side of the car chassis through two mounting holes to support the system components.

10. The electromechanical braking system as claimed in claim 1, characterized in that, Also includes: The parking function is implemented by the parking mechanism, which is equipped with an electromagnet assembly (41) installed on the support housing (4), a ratchet (8) fixed on the output shaft of the motor (1), and one end of the corresponding pawl (6) fixed to the pawl E-type retaining ring (7) through the pawl fixing shaft (5) installed on the support housing (4). The other end of the pawl (6) is connected to the electromagnet assembly (41) to form a closing and opening mechanism with the ratchet (8), thereby realizing the opening and release of parking.

11. The electromechanical braking system as claimed in claim 1, characterized in that, Also includes: The inner hole of the double gear (14) is embedded in the double row ball bearing (16) and the outer ring of the bearing is fixed by the double row ball bearing retainer (15). The inner hole of the double row ball bearing (16) is press-fitted onto the gear shaft (17). The gear shaft (17) is fixed onto the support housing (4). A small hole is opened at the bottom end of the gear shaft (17) corresponding to the support housing (4) to facilitate press-fit ventilation. A tolerance ring (18) is provided at the end of the gear shaft (17) that is assembled with the ECU housing for centering.

12. The electromechanical braking system as claimed in claim 1, characterized in that, Also includes: The outer end face of the force sensor (25) is provided with a groove that matches the inner hole of the caliper body (30) with the protrusion at the mounting point to prevent it from rotating. The inner hole of the force sensor (25) passes through the planetary roller screw (27) shaft and is mounted between the thrust needle bearing (26) and the wall of the caliper body (30). The wiring harness of the force sensor (25) passes through the opening of the caliper body (30) and connects to the ECU. A sealing mechanism is provided between the wiring harness and the hole of the caliper body (30).

13. The electromechanical braking system as claimed in claim 1, characterized in that, Also includes: The planetary roller screw (27) and the thrust needle roller bearing (26) are lubricated with extreme pressure grease.

14. The electromechanical braking system as claimed in claim 1, characterized in that, Also includes: The motor (1) is fastened and sealed to the support housing (4) by bolts and sealing rings. The ratchet (8) mounted on the output shaft of the motor (1) cooperates with the pawl to realize the parking function. The motor gear (9) cooperates with the double gear (14) to realize speed reduction and torque increase. The motor position sensor (10) is set at the end of the output shaft of the motor (1) to output signals to the surrounding chips. The three-phase PIN of the motor (1) is directly inserted into the corresponding slot of the PCBA (12).

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