EMB motor assembly and braking system

Abstract

The invention discloses an EMB motor assembly and a braking system, and relates to the technical field of vehicle braking. The EMB motor assembly comprises a motor main body, a planetary gear set and a control circuit board, the motor main body comprises a shell, a stator assembly and a rotor assembly, the stator assembly comprises a stator coil and a busbar electrically connected with the stator coil, the stator coil comprises a first three-phase winding and a second three-phase winding which have a spatial phase difference, and the first three-phase winding and the second three-phase winding are arranged in the shell. The rotor assembly comprises a rotor body and a rotor shaft which are coaxially connected, the rotor body is rotatably arranged in the shell, the rotor shaft penetrates through the front end face of the shell and extends out of the shell, and the front end face is concaved inwards to form a fixing groove. The planetary gear set is fixedly arranged in the fixing groove to reduce speed and increase torque. The control circuit board is arranged on the side, facing the front end face, of the shell, the control circuit board and the output gear are arranged at intervals, and the busbar penetrates through the front end face and is electrically connected with the control circuit board. According to the EMB motor assembly, the axial size is greatly reduced, the space occupied by the EMB motor assembly can be reduced, and the structure is simplified.

Description

Technical Field

[0001] The present invention relates to the technical field of vehicle braking, and particularly to an EMB motor assembly and a braking system. Background Art

[0002] With the rapid development of electrification and intelligence in the automotive industry, there are more and more by-wire products in automobiles. In order to adapt to autonomous driving technology and improve the response speed of the braking system, the braking system of automobiles has begun to transform from a hydraulic electronic braking system (EHB) to a mechanical electronic braking system (EMB) powered by an EMB motor assembly.

[0003] However, due to the relatively low voltage level of the vehicle's voltage platform, a large driving current is required to achieve the required power, which easily generates heat. To ensure safety, the wire diameter of the EMB motor assembly is relatively thick. With a planetary gear set for speed reduction and torque increase, the axial dimension of the EMB motor assembly is relatively large under the premise of a certain power, occupying the chassis space. Summary of the Invention

[0004] The purpose of the present invention is to provide an EMB motor assembly and a braking system, which greatly reduce the axial dimension of the EMB motor assembly, can reduce the space occupied by the EMB motor assembly, and simplify the structure.

[0005] To achieve this purpose, the present invention adopts the following technical solutions:

[0006] An EMB motor assembly, comprising:

[0007] A motor main body, including a housing, a stator assembly, and a rotor assembly. The stator assembly includes a stator coil and a busbar electrically connected to the stator coil. The rotor assembly includes a rotor main body and a rotor shaft coaxially connected. The rotor main body is rotatably arranged in the housing, the rotor shaft passes through the front end face of the housing and extends out of the housing, and the front end face is recessed to form a fixing groove;

[0008] A planetary gear set, which includes a sun gear, a plurality of planet gears, a planet carrier, and an outer gear ring. The outer gear ring is fixedly arranged in the fixing groove, the sun gear is connected to the rotor shaft, the planet carrier is rotatably arranged in the outer gear ring, a plurality of the planet gears are rotatably arranged on the planet carrier, and a plurality of the planet gears are meshed with both the sun gear and the outer gear ring. An output gear is arranged at one end of the planet carrier away from the front end face;

[0009] A control circuit board, which is arranged on one side facing the front end face of the housing and is spaced from the output gear. The busbar passes through the front end face and is electrically connected to the control circuit board.

[0010] As an alternative to the above-mentioned EMB motor assembly, the stator assembly includes a first three-phase winding and a second three-phase winding, and there is a spatial phase difference between the first three-phase winding and the second three-phase winding.

[0011] As an alternative to the above-mentioned EMB motor assembly, the EMB motor assembly further includes an angle detection component, which includes a magnet and a sensor chip. The rotor shaft passes through the planet carrier, the magnet is arranged at one end of the rotor shaft facing the control circuit board, the sensor chip is arranged on the control circuit board, and the sensor chip can detect the rotation angle of the rotor shaft according to the magnetic field direction of the magnet.

[0012] As an alternative to the above-mentioned EMB motor assembly, the planet carrier is provided with a central hole, and a third bearing is embedded in the central hole. The rotor shaft passes through the central hole and is rotatably arranged in the third bearing.

[0013] As an alternative to the above-mentioned EMB motor assembly, the planetary gear set further includes a fixed housing, which is buckled on the outer gear ring to form an accommodation cavity between the fixed housing and the outer gear ring. The sun gear, the planetary gears and part of the planet carrier are all arranged in the accommodation cavity.

[0014] As an alternative to the above-mentioned EMB motor assembly, the outer periphery of the fixed housing is provided with a limit protrusion, the housing is provided with a bayonet, the fixed housing is arranged in the fixed groove and is in limit contact with the inner wall of the fixed groove, and the limit protrusion is snapped into the bayonet and is in interference fit with the bayonet.

[0015] As an alternative to the above-mentioned EMB motor assembly, the housing includes a main housing and an inner housing. The main housing is an open structure with a main cavity. The inner housing is fixedly arranged at the opening of the main housing. The outer periphery of the inner housing is provided with a notch. The side of the inner housing facing the control circuit board is the front end face, and the bus bar passes through the front end face through the notch.

[0016] As an alternative to the above-mentioned EMB motor assembly, the main housing is provided with a first bearing groove, and a first bearing is fixedly arranged in the first bearing groove. The rotor shaft passes through the first bearing; and / or,

[0017] The bottom surface of the fixed groove of the inner housing is concavely formed with a second bearing groove, and a second bearing is fixedly arranged in the second bearing groove. The rotor shaft passes through the second bearing.

[0018] As an alternative to the above-mentioned EMB motor assembly, at least two output gears are coaxially arranged on the planet carrier, and the transmission ratios and / or outer diameters of at least two output gears are different.

[0019] A braking system includes the EMB motor assembly described above, and further includes a brake pedal and a brake caliper. The brake pedal is communicatively connected to the control circuit board, and the brake caliper is drivingly connected to the output gear.

[0020] Advantages of the present invention:

[0021] The present invention provides an EMB motor assembly and a braking system. In this EMB motor assembly, the motor body is excited by the stator coil to drive the rotor shaft of the rotor assembly to rotate. After decelerating and increasing torque through the planetary gear set, power is output externally by the output gear. Since the stator coil is of a double-three-phase structure, the control circuit board can provide drive current for the motor body through six-phase lines, which can significantly reduce the magnitude of the current in each phase, thereby reducing the heat generation. Moreover, it is possible to use a wire harness with a smaller wire diameter, reducing the size of the stator coil, enabling the front end face to be recessed to form a fixing groove, and allowing the planetary gear set to be embedded in the motor body, thus significantly reducing the axial dimension of the EMB motor assembly, which is beneficial for the layout of the entire vehicle. Since there is no other structure at the front end of the output gear, the control circuit board is arranged on the side facing the front end face of the housing and is spaced from the output gear, which can further reduce the space occupied by the EMB motor assembly, and the busbar can be directly connected to the circuit board without bending, simplifying the structure. Description of the Drawings

[0022] Figure 1 is a side view of the EMB motor assembly provided by the present invention;

[0023] Figure 2 is a cross-sectional view of the EMB motor assembly provided by the present invention;

[0024] Figure 3 is an exploded view of the EMB motor assembly provided by the present invention;

[0025] Figure 4 is a structural schematic diagram of the housing provided by the present invention;

[0026] Figure 5 is a structural schematic diagram of the external gear ring and the fixed housing provided by the present invention.

[0027] In the figure:

[0028] 1. Motor body; 11. Housing; 111. Main housing; 1111. First bearing groove; 112. Inner housing; 1121. Front end face; 1122. Fixing groove; 1123. Bayonet; 1124. Notch; 1125. Second bearing groove; 12. Stator assembly; 121. Stator coil; 122. Busbar; 13. Rotor assembly; 131. Rotor body; 132. Rotor shaft; 14. First bearing; 15. Second bearing;

[0029] 2. Planetary gear set; 21. Sun gear; 22. Planet gear; 23. Planet carrier; 231. Carrier main body; 232. Extension shaft; 233. Protrusion; 234. Central hole; 24. Ring gear; 25. Output gear; 26. Third bearing; 27. Fixed housing; 271. Output hole; 272. Limit retaining ring; 273. Limit protrusion;

[0030] 3. Control circuit board;

[0031] 41. Magnet; 42. Sensor chip. Detailed implementation manners

[0032] The embodiments of the present invention will be described in detail below. The examples of the embodiments are shown in the accompanying drawings, where the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by referring to the accompanying drawings are exemplary and are intended to explain the present invention, and should not be construed as a limitation to the present invention.

[0033] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present invention. In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. Among them, the terms "first position" and "second position" are two different positions.

[0034] Unless otherwise clearly specified and defined, the terms "mounted", "connected", "connected to", "fixed" should be understood in a broad sense. For example, it can be a fixed connection or a detachable connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0035] Unless otherwise clearly specified and defined, the first feature being "on" or "under" the second feature may include direct contact between the first feature and the second feature, or may include the situation where the first feature and the second feature are not in direct contact but are in contact through additional features therebetween. Moreover, the first feature being "above", "over" and "on top of" the second feature includes that the first feature is directly above and obliquely above the second feature, or simply means that the first feature is at a higher horizontal height than the second feature. The first feature being "under", "beneath" and "underneath" the second feature includes that the first feature is directly below and obliquely below the second feature, or simply means that the first feature is at a lower horizontal height than the second feature.

[0036] The technical solution of the present invention will be further described below in conjunction with the accompanying drawings and through specific embodiments.

[0037] This embodiment provides a braking system for braking an automobile. The braking system includes a power structure, a brake pedal and a brake caliper. The power structure can act according to the stroke of the brake pedal, and reduces the speed and increases the torque through a reduction gear train, so as to control the movement of the brake caliper, and enable the brake caliper to drive the friction pad to press against the brake disc, thereby generating a parking braking force.

[0038] In this embodiment, the braking system is a mechanical electronic braking system (EMB). The mechanical electronic braking system (EMB) has the advantages of faster response speed and better adaptation to autonomous driving technology. Correspondingly, its power structure is an EMB motor assembly. The EMB motor assembly can control the braking force of the brake caliper through the displacement signal of the brake pedal, so as to achieve the purpose of decelerating the automobile.

[0039] As Figures 1 to 4 shown, this embodiment also provides an EMB motor assembly. The EMB motor assembly includes a motor main body 1 and a control circuit board 3. The motor main body 1 includes a housing 11, a stator assembly 12 and a rotor assembly 13. The stator assembly 12 includes a stator coil 121 and a busbar 122 electrically connected to the stator coil 121. The rotor assembly 13 includes a rotor main body 131 and a rotor shaft 132 coaxially connected. The rotor main body 131 is rotatably arranged in the housing 11. The rotor shaft 132 passes through the front end face 1121 of the housing 11 and extends out of the housing 11. The brake pedal is communicatively connected to the control circuit board 3, and the busbar 122 is electrically connected to the control circuit board 3.

[0040] Wherein, the control circuit board 3 can receive the displacement signal of the brake pedal, and control the magnitude and direction of the current in the stator coil 121 through the busbar 122, so as to establish a changing magnetic field. The rotor main body 131 is provided with a permanent magnet 41, and the rotor main body 131 can be rotated by controlling the change of the magnetic field.

[0041] As Figure 2 andFigure 3 As shown, the reduction gear train of the braking system is a planetary gear set 2. The planetary gear set 2 includes a sun gear 21, a plurality of planet gears 22, a planet carrier 23, and an external gear ring 24. The sun gear 21 is connected to the rotor shaft 132. The planet carrier 23 is rotatably arranged inside the external gear ring 24. The plurality of planet gears 22 are rotatably arranged on the planet carrier 23, and the plurality of planet gears 22 mesh with both the sun gear 21 and the external gear ring 24. An output gear 25 is provided at one end of the planet carrier 23 away from the front end face 1121.

[0042] In this EMB motor assembly, the motor body 1 is excited by the stator coil 121 to drive the rotor shaft 132 of the rotor assembly 13 to rotate, and drives the planet gears 22 to rotate through the sun gear 21. Since the external gear ring 24 is fixedly connected to the housing 11 of the motor body 1, at this time, the planet gears 22 drive the planet carrier 23 to rotate by rotating along the external gear ring 24, and provide power externally through the output gear 25 of the planet carrier 23. The planetary gear set 2 has a compact structure, saves space, and has a high power density. The plurality of planet gears 22 share the load at the same time, so that the load-bearing capacity of the planetary gear set 2 is significantly improved. At the same time, the load distribution of the planetary gear set 2 is uniform. The plurality of planet gears 22 mesh at the same time, and the load is evenly distributed to multiple gears, reducing the wear of a single gear and extending the service life.

[0043] In this embodiment, teeth are provided on the outer periphery of the rotor shaft 132 to form the sun gear 21. That is to say, the sun gear 21 and the rotor shaft 132 are of an integral structure, which is convenient for processing and reduces costs.

[0044] In this embodiment, the stator assembly 12 includes a first three-phase winding and a second three-phase winding, and there is a spatial phase difference between the first three-phase winding and the second three-phase winding. That is to say, the motor body 1 is a six-phase motor with a double three-phase structure, having two sets of three-phase PINs of U / V / W. When working normally, the controller can supply current to the motor through the six-phase PIN at the same time, significantly reducing the driving current of the controller, being able to significantly reduce the magnitude of the current of each phase, thereby reducing the heat generation, and thus being able to use a wire harness with a smaller wire diameter accordingly, improving the heat generation and assembly processability. Due to the reduction of heat generation, the planetary gear set 2 can select more economical materials, which is beneficial to cost reduction and at the same time improves the durability of the product.

[0045] Moreover, the six-phase motor can reduce the magnitude of the current of each phase on the premise of ensuring the output capacity, thereby reducing the size of the terminals of the bus bar 122, thus making room for the arrangement of the planetary gear set 2, improving the design of the planetary gear set 2, increasing the transmission ratio of the planetary gear set 2, and thus providing a higher transmission torque, which is beneficial to the size optimization of the assembly product.

[0046] However, since the EMB motor assembly needs to achieve the function of speed reduction and torque increase through the planetary gear set 2, and the motor body 1 and the planetary gear set 2 are axially arranged, it results in a relatively large axial dimension of the EMB motor assembly under the premise of a certain power, that is, when the sizes of the motor body 1 and the planetary gear set 2 remain unchanged, which occupies the chassis space.

[0047] As Figures 2 to 4 shown, to solve the above problems, in the EMB motor assembly provided in this embodiment, a fixing groove 1122 is formed by concave inward on the front end face 1121 of the housing 11 of the motor body 1, the external gear ring 24 is fixedly arranged in the fixing groove 1122, and the control circuit board 3 is arranged on the side facing the front end face 1121 of the housing 11 and is spaced from the output gear 25, and the bus bar 122 passes through the front end face 1121 and is electrically connected to the control circuit board 3.

[0048] The front end face 1121 of the motor body 1 is concave inward to form the fixing groove 1122, enabling the planetary gear set 2 to be embedded in the motor body 1, and the axial free space of the motor body 1 can be fully utilized without changing the structures of the stator assembly 12 and the rotor assembly 13, thereby greatly reducing the axial dimension of the EMB motor assembly; since there is no other structure in front of the front end of the output gear 25, the control circuit board 3 is arranged on the side facing the front end face 1121 of the housing 11 and is spaced from the output gear 25, which can further reduce the space occupied by the EMB motor assembly, and the bus bar 122 can be directly connected to the circuit board without bending, simplifying the structure.

[0049] As Figures 2 to 5 shown, the planetary gear set 2 further includes a fixing housing 27, and the fixing housing 27 is buckled on the external gear ring 24 to form a receiving cavity between the fixing housing 27 and the external gear ring 24. The sun gear 21, the planetary gear 22 and a part of the planetary carrier 23 are all arranged in the receiving cavity. The fixing housing 27 is buckled on the external gear ring 24, making the entire planetary gear set 2 form an integral module, ensuring the stability of the planetary gear set 2 during operation, facilitating the installation and disassembly of the planetary gear set 2, and reducing the production and material preparation costs.

[0050] Further, a limiting protrusion 273 is arranged on the outer periphery of the fixing housing 27, a bayonet 1123 is arranged on the housing 11, the fixing housing 27 is arranged in the fixing groove 1122 and is in limiting contact with the inner wall of the fixing groove 1122, and the limiting protrusion 273 is snapped into the bayonet 1123 and is in interference fit with the bayonet 1123. The inner wall of the fixing groove 1122 can play a role in radially limiting the fixing housing 27, and the interference fit between the limiting protrusion 273 and the bayonet 1123 can play a role in axially limiting and circumferentially angularly limiting the fixing housing 27, thereby ensuring the relative stability between the fixing housing 27 and the housing 11 of the motor body 1 during the operation of the EMB motor assembly.

[0051] AsFigures 2 to 4 As shown in the figure, the housing 11 includes a main housing 111 and an inner housing 112. The main housing 111 is an open structure with a main cavity, and the inner housing 112 is fixedly arranged at the opening of the main housing 111. This structure facilitates the disassembly and installation of the motor main body 1. Thus, the stator assembly 12 and the rotor assembly 13 are arranged in the main cavity of the main housing 111, and the inner housing 112 is used to block the opening to prevent the stator assembly 12 and the rotor assembly 13 from falling out of the main cavity.

[0052] Among them, the rotor shaft 132 of the rotor assembly 13 extends out of the housing 11 through the inner housing 112 for power output. Therefore, the side of the inner housing 112 facing the control circuit board 3 is the front end face 1121. That is to say, the fixing groove 1122 is concavely formed from the inner housing 112 towards the inside of the main cavity. The planetary gear set 2 is arranged on the inner housing 112, and a notch 1124 is provided on the outer periphery of the inner housing 112. The bus bar 122 passes through the front end face 1121 through the notch 1124 to be electrically connected to the control circuit board 3.

[0053] As Figure 2 and Figure 4 shown in the figure, the housing 11 is provided with a first bearing groove 1111, and a first bearing 14 is fixedly arranged in the first bearing groove 1111. The rotor shaft 132 is inserted through the first bearing 14. The first bearing groove 1111 is used to fix the first bearing 14, so that the first bearing 14 can greatly reduce the friction generated by the rotation of the rotor shaft 132, which can not only improve the service life but also enable the rotor shaft 132 to rotate stably. Similarly, the housing 11 is also provided with a second bearing groove 1125, and a second bearing 15 is fixedly arranged in the second bearing groove 1125. The rotor shaft 132 is inserted through the second bearing 15.

[0054] To ensure the stability of the rotor shaft 132 during rotation, the first bearing 14 and the second bearing 15 are respectively located at both ends of the rotor body 131 along the axial direction. Therefore, the first bearing groove 1111 can be arranged on the bottom surface of the main housing 111. In order to avoid the rotor shaft 132 needing to penetrate the bottom surface of the main housing 111, the first bearing groove 1111 is formed by protruding from the bottom surface of the main housing 111, and the first bearing 14 is located in the main cavity.

[0055] It is worth noting that the bottom surface of the main housing 111 is concave to form an avoidance groove from the outside of the main housing 111, and then the bottom surface of the avoidance groove protrudes, so as to form the first bearing groove 1111 in the main cavity. This structure can reduce the size of the first bearing groove 1111 protruding from the main housing 111, thereby reducing the axial size of the motor main body 1.

[0056] In this embodiment, the bottom surface of the fixing groove 1122 of the inner housing 112 is concave to form a second bearing groove 1125. Under this structure, the rotor shaft 132 needs to pass through the inner housing 112 before passing through the second bearing 15. However, since the rotor shaft 132 itself needs to pass through the inner housing 112 to output power, it does not cause additional sealing requirements for the motor body 1. Moreover, since the second bearing groove 1125 is formed by continuing to be concave on the bottom surface of the fixing groove 1122, during molding, the inner housing 112 can be molded once by stamping or casting, which greatly reduces the cost.

[0057] like Figure 2 As shown, the planetary carrier 23 includes a bracket body 231, a protrusion 233 and a plurality of protruding shafts 232. The bracket body 231 is rotatably disposed in the outer gear ring 24. The plurality of protruding shafts 232 are connected to the bracket body 231 and extend toward the front end surface 1121. The planetary gear 22 is rotatably disposed on the protruding shaft 232. The protrusion 233 is disposed on the bracket body 231 and is located at an end away from the protruding shaft 232. The output gear 25 is disposed on the protrusion 233.

[0058] Among them, the bracket body 231 is located on the side of the planetary gear 22 away from the front end face 1121, so that the bracket body plays the role of a cover, preventing the planetary gear 22 from being exposed to the external environment and easily absorbing dust or debris particles to cause unnecessary wear, thereby extending the service life and ensuring the normal operation of the planetary gear set 2.

[0059] Specifically, the fixed housing 27 has an output hole 271, and a limit retaining ring 272 is provided on the inner wall of the output hole 271. The bracket body 231 is provided on the side of the limit retaining ring 272 facing the front end surface 1121 and is in sliding contact with the limit retaining ring 272, and the extension shaft 232 extends out of the output hole 271 to output power. The limit retaining ring 272 can not only limit the axial movement of the planetary carrier 23, but also contact with the bracket body to prevent external dust or debris particles from entering the interior of the planetary gear set 2.

[0060] In this embodiment, the planet carrier 23 is coaxially provided with at least two output gears 25, and the transmission ratios and / or outer diameters of the at least two output gears 25 are different. In other words, the motor body 1 can drive the caliper of the vehicle to move through different transmission ratios, thereby improving the adjustability of the braking force and braking time during braking.

[0061] It is worth noting that for the mechanical electronic brake system (EMB), it is necessary to monitor the angular position of the rotor shaft 132 in the rotor assembly 13 at any time to ensure that the control circuit board 3 controls the rotation of the rotor shaft 132, and the rotation angle of the rotor shaft 132 is accurate, so as to provide appropriate braking force for the vehicle.

[0062] like Figures 1 to 3As shown in the figure, to achieve the above object, the EMB motor assembly further includes an angle detection component. The angle detection component includes a magnet 41 and a sensor chip 42. The rotor shaft 132 passes through the planet carrier 23. The magnet 41 is arranged at one end of the rotor shaft 132 facing the control circuit board 3, and the sensor chip 42 is arranged on the control circuit board 3. The sensor chip 42 can detect the rotation angle of the rotor shaft 132 according to the magnetic field direction of the magnet 41.

[0063] It can be understood that the magnet 41 has its own magnetic field. The sensor chip 42 can determine the angular position of the rotor shaft 132 at this time by detecting the magnetic field direction. And when the rotor shaft 132 rotates, the magnetic field of the magnet 41 will also rotate accordingly to ensure the accuracy of the detection of the angular position of the rotor shaft 132. It is worth noting that the direction of the N pole - S pole of the magnet 41 is perpendicular to the axial direction of the rotor shaft 132.

[0064] Specifically, the planet carrier 23 is provided with a central hole 234, and the rotor shaft 132 passes through the central hole 234 so that the magnet 41 at the end can be close to the sensor chip 42. It can be understood that after the deceleration of the planetary gear set 2, the rotational speeds of the rotor shaft 132 and the planet carrier 23 are different, and there is relative rotation between the rotor shaft 132 and the planet carrier 23. And if the rotor shaft 132 is to rotate stably, the planet carrier 23 needs to be in sliding contact with the rotor shaft 132, which easily causes friction between the rotor shaft 132 and the planet carrier 23 and affects the output torque and service life.

[0065] As Figure 2 and Figure 3 shown in the figure, to solve the above problems, a third bearing 26 is embedded in the central hole 234, and the rotor shaft 132 passes through the central hole 234 and is rotatably arranged in the third bearing 26. The third bearing 26 can provide radial limit for the rotor shaft 132 near one end where the rotor shaft 132 is close to the magnet 41, thereby ensuring the stability of the position of the magnet 41, ensuring that the magnetic field change sensed by the sensor chip 42 is completely caused by the rotation of the magnet 41, improving the monitoring accuracy, and at the same time greatly reducing the friction when the rotor shaft 132 rotates relative to the bracket body.

[0066] In this embodiment, the third bearing 26 is a sliding bearing. The sliding bearing is press - fitted in the central hole 234, and a polymer coating is embedded on the inner surface to provide lubrication and reduce friction.

[0067] The above content is only the preferred embodiment of the present invention. For those of ordinary skill in the art, according to the idea of the present invention, there will be changes in the specific implementation manner and application scope. The content of this specification should not be construed as a limitation of the present invention.

Claims

1. An EMB motor assembly, characterized in that, Comprising: The motor main body (1) includes a housing (11), a stator assembly (12), and a rotor assembly (13). The stator assembly (12) includes a stator coil (121) and a bus bar (122) electrically connected to the stator coil (121). The stator coil includes a first three-phase winding and a second three-phase winding, and there is a spatial phase difference between the first three-phase winding and the second three-phase winding. The rotor assembly (13) includes a rotor main body (131) and a rotor shaft (132) connected coaxially. The rotor main body (131) is rotatably arranged within the housing (11), and the rotor shaft (132) passes through the front end face (1121) of the housing (11) and extends out of the housing (11). The front end face (1121) is recessed to form a fixing groove (1122). The planetary gear set (2) is fixedly arranged within the fixing groove (1122). The planetary gear set (2) is in transmission connection with the rotor shaft (132) to reduce speed and increase torque, and outputs power through an output gear (25). The control circuit board (3) is arranged on one side facing the front end face (1121) of the housing (11) and is spaced from the output gear (25). The bus bar (122) passes through the front end face (1121) and is electrically connected to the control circuit board (3).

2. The EMB motor assembly according to claim 1, wherein, The planetary gear set (2) includes a sun gear (21), a plurality of planet gears (22), a planet carrier (23), and an outer gear ring (24). The outer gear ring (24) is fixedly arranged within the fixing groove (1122). The sun gear (21) is connected to the rotor shaft (132). The planet carrier (23) is rotatably arranged within the outer gear ring (24). A plurality of the planet gears (22) are rotatably arranged on the planet carrier (23), and the plurality of planet gears (22) are meshed with both the sun gear (21) and the outer gear ring (24). The output gear (25) is arranged at one end of the planet carrier (23) away from the front end face (1121).

3. The EMB motor assembly according to claim 2, wherein, The EMB motor assembly further includes an angle detection assembly. The angle detection assembly includes a magnet (41) and a sensor chip (42). The rotor shaft (132) passes through the planet carrier (23). The magnet (41) is arranged at one end of the rotor shaft (132) facing the control circuit board (3). The sensor chip (42) is arranged on the control circuit board (3). The sensor chip (42) can detect the rotation angle of the rotor shaft (132) according to the magnetic field direction of the magnet (41).

4. The EMB motor assembly according to claim 3, wherein The planet carrier (23) is provided with a central hole (234), and a third bearing (26) is embedded in the central hole (234). The rotor shaft (132) passes through the central hole (234) and is rotatably arranged within the third bearing (26).

5. The EMB motor assembly according to claim 2, wherein The planetary gear set (2) further comprises a fixed housing (27), wherein the fixed housing (27) is engaged with the outer gear ring (24) to form an accommodating cavity between the fixed housing (27) and the outer gear ring (24), and the sun gear (21), the planetary gears (22) and part of the planet carrier (23) are all arranged in the accommodating cavity.

6. The EMB motor assembly according to claim 5, characterized in that, The outer periphery of the fixed shell (27) is provided with a limiting protrusion (273), the outer shell (11) is provided with a bayonet (1123), the fixed shell (27) is arranged in the fixed groove (1122) and is in limiting contact with the inner wall of the fixed groove (1122), and the limiting protrusion (273) is inserted into the bayonet (1123) and is interference fit with the bayonet (1123).

7. The EMB motor assembly according to claim 1, wherein The outer shell (11) comprises a main shell (111) and an inner shell (112); the main shell (111) is an open structure having a main cavity; the inner shell (112) is fixedly arranged at the opening of the main shell (111); a notch (1124) is arranged on the outer periphery of the inner shell (112); the side of the inner shell (112) facing the control circuit board (3) is the front end surface (1121); and the bus bar (122) passes through the front end surface (1121) through the notch (1124).

8. The EMB motor assembly according to claim 7, wherein, The main housing (111) is provided with a first bearing groove (1111), a first bearing (14) is fixedly arranged in the first bearing groove (1111), and the rotor shaft (132) passes through the first bearing (14); and / or, The bottom surface of the fixing groove (1122) of the inner shell (112) is concave to form a second bearing groove (1125), a second bearing (15) is fixedly arranged in the second bearing groove (1125), and the rotor shaft (132) passes through the second bearing (15).

9. The EMB motor assembly according to claim 2, wherein The planet carrier (23) is coaxially provided with at least two output gears (25), and the transmission ratios and / or outer diameters of the at least two output gears (25) are different.

10. A braking system, characterized in that, The EMB motor assembly comprises any one of claims 1 to 9, and further comprises a brake pedal and a brake caliper, wherein the brake pedal is communicatively connected to the control circuit board (3), and the brake caliper is transmission-connected to the output gear (25).

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