Electro-mechanical brake device having embedded lead screw, electro-mechanical brake system and vehicle

Abstract

Provided in the present application are an electro-mechanical brake device having an embedded lead screw, an electro-mechanical brake system and a vehicle. The electro-mechanical brake device comprises a housing, a brake motor, a speed reducer and a lead screw, wherein the brake motor is configured to drive the lead screw by means of the speed reducer to drive a friction plate; the housing is configured to accommodate a stator and a rotor of the brake motor, a planetary gearset of the speed reducer, and the lead screw; the stator and the planetary gearset are arranged in an axial direction of the brake motor, and the planetary gearset is configured to be drivingly connected to the rotor and the lead screw; the stator, the rotor and the lead screw are coaxially arranged; and the lead screw is at least partially embedded in a central hole of the stator or the rotor. In the electro-mechanical brake device of the present application, the lead screw is at least partially embedded in the central hole of the stator or the rotor, thus reducing the axial size of the electron-mechanical brake device, and achieving miniaturization.

Description

Electromechanical brake device, system and vehicle with built-in lead screw

[0001] This application claims priority to the Chinese patent application filed with the State Intellectual Property Office of China on November 22, 2023, with application number 202311575683.9, and priority to the Chinese patent application entitled “Electronic mechanical braking device, system and vehicle with embedded screw”, all contents of which are incorporated by reference into this application. Technical Field

[0002] The present application relates to the field of vehicles, and in particular to an electromechanical brake device with an embedded lead screw, an electromechanical brake system, and a vehicle. Background Art

[0003] Electromechanical brakes (EMBs) utilize a motor and mechanical transmission mechanism to actuate the brakes. They offer a simple structure, responsiveness, smooth load transfer, and the absence of hydraulic piping, resulting in high transmission efficiency. Furthermore, EMBs are trending towards miniaturization to accommodate wheel space. Summary of the Invention

[0004] This application provides an electronic mechanical brake device, system, and vehicle with an embedded lead screw. By embedding at least partially the lead screw of the electronic mechanical brake device within the center hole of the stator or rotor, the axial dimensions of the electronic mechanical brake device are reduced and miniaturization is achieved. This application specifically includes the following technical solutions:

[0005] In a first aspect, an electromechanical brake device with an embedded lead screw comprises a housing, a brake motor, a reducer, and a lead screw. The brake motor is configured to drive the lead screw through the reducer to drive a friction plate, wherein:

[0006] The housing is used to accommodate the stator, rotor, planetary gear set of the reducer, and the lead screw of the brake motor;

[0007] The rotor and the planetary gear set are arranged along the axial direction of the brake motor, and the planetary gear set is used to transmit and connect the rotor and the lead screw;

[0008] The stator, rotor and lead screw are coaxially arranged, and the lead screw is at least partially embedded in the center hole of the stator or rotor.

[0009] The electronic mechanical brake device of the present application drives a reducer through a brake motor to drive a lead screw to achieve braking. Along the axial direction of the brake motor, the planetary gear set of the reducer is coaxially driven with the lead screw, and the planetary gear set is arranged adjacent to the stator of the brake motor. Along the radial direction of the brake motor, the stator and rotor of the brake motor are sleeved on the outside of the lead screw. The electronic mechanical brake device of the present application embeds at least part of the lead screw in the center hole of the stator or rotor, which compresses the size of the electronic mechanical brake device along the axial direction of the brake motor. On the premise of ensuring reliable braking of the electronic mechanical brake device, the overall volume of the electronic mechanical brake device is compressed to achieve miniaturization.

[0010] In one implementation, the electronic mechanical brake device includes a screw sleeve, which is sleeved on a lead screw. The lead screw is used to rotate with the output shaft and drive the screw sleeve to slide along the axial direction of the output shaft to drive the friction plate.

[0011] In this implementation, through the coordinated transmission of the sleeve and the screw, the rotational motion of the screw along the output shaft can be converted into axial sliding of the sleeve along the output shaft, thereby driving the friction plate to slide axially along the output shaft to achieve braking.

[0012] In one implementation, the electronic mechanical brake device includes a support tube, which is coaxially arranged with the stator, rotor and screw. The inner circumference of the support tube is used to support the screw sleeve, and the support tube is at least partially embedded in the center hole of the stator or rotor.

[0013] In this implementation, the housing includes a support cylinder extending along the axial direction of the brake motor. The support cylinder extends into the gap between the rotor of the brake motor and the screw sleeve to guide the screw sleeve to slide along the axial direction of the output shaft.

[0014] In one implementation, a mutually cooperating anti-rotation protrusion and anti-rotation notch are provided between the outer circumference of the screw sleeve and the inner circumference of the support tube. The anti-rotation protrusion extends into the anti-rotation notch along the radial direction of the screw sleeve to limit the rotation of the screw sleeve in the support tube.

[0015] In this implementation, the outer circumference of the screw sleeve and the inner circumference of the support tube cooperate with each other through the anti-rotation protrusion and the anti-rotation notch, which can limit the rotation of the screw sleeve in the support tube to form friction loss, thereby improving the braking efficiency of the electronic mechanical brake device.

[0016] In one implementation, the inner circumference of the housing is used to fix the outer circumference of the stator, and the central hole of the stator is used to accommodate the rotor; or,

[0017] The outer circumference of the support cylinder is used to fix the inner circumference of the stator, and the central hole of the rotor is used to accommodate the stator.

[0018] In this implementation, the brake motor can be an inner rotor motor, the stator of which is fixed to the inner circumference of the housing; or it can be an outer rotor motor, the rotor of which is fixed to the outer circumference of the support tube.

[0019] In one implementation, the brake motor includes at least two motor shafts, which are fixed to the rotor at equal intervals along the circumference of the brake motor. Each motor shaft is used to transmit and connect the rotor and the planetary gear in the planetary gear set. The rotor drives the planetary gear through the motor shaft and drives the output shaft of the reducer to rotate.

[0020] In this implementation, the motor shaft of the brake motor is used to drive the connection between the rotor and the planetary gears in the planetary gear set. The rotor of the brake motor drives the planetary gears to rotate, thereby driving the planetary gear set. The sun gear of the planetary gear set is driven coaxially with the lead screw.

[0021] In one implementation, the planetary gear set includes two planetary gear trains, which are spaced apart along the axial direction of the brake motor, wherein:

[0022] The housing is used to fix the sun gear in the planetary gear train away from the stator, and the output shaft of the reducer is used to coaxially drive another sun gear;

[0023] Each motor shaft is used to transmit and connect the rotor and two planetary gears, and the two planetary gears belong to two planetary gear trains.

[0024] In this implementation, the two-stage planetary gear train transmission can increase the transmission ratio of the reducer. By fixing one of the sun gears in the two planetary gear trains and connecting the other to the output shaft, the reduction function of the planetary gear set can be achieved.

[0025] In one implementation, the rotor of the brake motor includes a rotor bracket and multiple magnetic sheets. The rotor bracket is cylindrical, at least two motor shafts are fixed to the rotor bracket, and multiple magnetic sheets are evenly surrounded and fixed on the circumferential surface of the rotor bracket facing the stator of the brake motor.

[0026] In this implementation, the rotor of the brake motor adopts a structure in which a magnetic sheet is attached to the surface of the rotor bracket, which can control the radial size of the rotor and facilitate the insertion of the lead screw into the center hole of the rotor or stator.

[0027] In one implementation, the electromechanical brake device includes a circuit board, the circuit board is used to fix a drive circuit, and the drive circuit is used to drive a brake motor, wherein:

[0028] Along the axial direction of the brake motor, the circuit board, the rotor of the brake motor and the planetary gear set of the reducer are arranged in sequence, and the circuit board and the planetary gear set are located on opposite sides of the rotor of the brake motor.

[0029] In this implementation, an integrated circuit board can also be incorporated into the electromechanical brake device, and the circuit board is disposed on the side of the planetary gear set away from the brake caliper, so as to facilitate coaxial transmission between the output shaft of the reducer and the brake caliper.

[0030] In one implementation, the electromechanical brake device includes a position sensor, which is used to detect the rotation angle of the brake motor. The position sensor includes a stator and a rotor, wherein:

[0031] The circuit board is used to fix the stator of the position sensor;

[0032] The output shaft of the reducer is used to coaxially drive the rotor of the position sensor.

[0033] In this implementation, the electronic mechanical brake device detects the rotation angle of the brake motor through a position sensor, and then controls the thrust of the friction plate driven by the electronic mechanical brake device to achieve control of the vehicle's braking force.

[0034] In one implementation, the end of the output shaft of the reducer away from the lead screw extends through the center hole of the planetary gear set toward the circuit board, the rotor of the position sensor is fixed to the output shaft of the reducer, and at least a portion of the inner hole of the stator of the position sensor is used to accommodate the rotor of the position sensor.

[0035] In this implementation, the position sensor's stator can be fixed to one side of the circuit board, allowing the output shaft of the reducer to coaxially drive the brake caliper. The other end of the output shaft can then pass through the center hole of the planetary gear set to coaxially drive the position sensor's rotor.

[0036] In one implementation, the electronic mechanical braking device includes a locking mechanism, which is used to lock or release the output shaft of the reducer. The locking mechanism is coaxially arranged with the output shaft and is used to lock or release the output shaft.

[0037] In this implementation, the locking mechanism cooperates with the output shaft to lock or release the transmission function of the reducer. In the transmission state, the reducer can be used to implement the braking function of the electromechanical brake; in the locked state, the reducer can be used to implement the parking function of the electromechanical brake.

[0038] In one implementation, the locking mechanism includes a sleeve, an electromagnetic coil and an axial displacement member. The sleeve is used to fix the outer peripheral surface of the output shaft, the electromagnetic coil is sleeved outside the sleeve, the circuit board is used to fix the control circuit of the electromagnetic coil, the control circuit is used to control the conduction or disconnection of the electromagnetic coil, and the electromagnetic coil is used to drive the axial displacement member to slide toward or away from the sleeve to lock or release the output shaft.

[0039] In this implementation, the locking mechanism is coaxially sleeved with the output shaft, and the locking mechanism controls the transmission function of the planetary gear set via a sleeve fixedly connected to the output shaft.

[0040] In one implementation, the electronic mechanical brake device includes a caliper, which is used to connect at least one friction plate, and the caliper is fixedly connected to the housing along the axial direction of the brake motor.

[0041] In one implementation, the caliper includes a main body, a pushing part, and a connecting part. The main body and the pushing part are spaced apart along the axial direction of the brake motor, and the connecting part fixedly connects the main body and the pushing part.

[0042] In one implementation, the caliper and the housing are an integrated structure.

[0043] In a second aspect, the present application provides an electronic mechanical braking system, comprising at least one friction plate and an electronic mechanical braking device provided by any of the above-mentioned implementations, the electronic mechanical braking device being used to drive at least one friction plate to move axially along a brake motor to brake a wheel.

[0044] In a third aspect, the present application provides a vehicle comprising wheels and the electronic mechanical braking system provided in the second aspect above, wherein the axis of the brake motor in the electronic mechanical braking system is parallel to the axis of the wheel, and the friction plate in the electronic mechanical braking system is used to move toward the brake disc of the wheel to brake the vehicle.

[0045] The electronic mechanical braking system provided in the second aspect of the present application and the vehicle provided in the third aspect adopt the above-mentioned electronic mechanical braking device. Under the premise of achieving reliable braking, the volume is controlled and can be adapted to the wheel side space. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] In order to more clearly illustrate the technical solution of the present application, the following is a brief introduction to the drawings required for use in the implementation. Obviously, the drawings described below are only some implementation methods of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0047] FIG1 is a schematic diagram of the appearance structure of a vehicle at the wheel provided in an embodiment of the present application;

[0048] FIG2 is a schematic diagram of a cross-sectional structure of a vehicle at a wheel provided in an embodiment of the present application;

[0049] FIG3 is a schematic cross-sectional view of an electromechanical braking device according to an embodiment of the present application;

[0050] FIG4 is a schematic structural diagram of a caliper in an electromechanical brake device provided in an embodiment of the present application;

[0051] FIG5 is a schematic diagram of the cross-sectional structure inside a housing of an electronic mechanical braking device provided in an embodiment of the present application;

[0052] FIG6 is a schematic diagram of the appearance structure of a housing in an electronic mechanical braking device provided in an embodiment of the present application;

[0053] FIG7 is a schematic structural diagram of a disassembled housing and internal components of an electronic mechanical brake device provided in an embodiment of the present application;

[0054] FIG8 is a simplified structural diagram of a housing and its internal components in an electronic mechanical brake device provided in an embodiment of the present application;

[0055] FIG9 is a schematic diagram of the appearance structure of a brake motor in an electronic mechanical brake device provided in an embodiment of the present application;

[0056] FIG10 is a schematic diagram of the exploded structure of a brake motor in an electromechanical brake device provided in an embodiment of the present application;

[0057] FIG11 is a schematic diagram of the appearance structure of a rotor of a brake motor in an electronic mechanical brake device provided in an embodiment of the present application;

[0058] FIG12 is a schematic diagram of the exploded structure of a rotor of a brake motor in an electronic mechanical brake device according to an embodiment of the present application;

[0059] FIG13 is a schematic diagram of the internal structure of the rotor and the planetary gear set in an electronic mechanical brake device provided by an embodiment of the present application;

[0060] FIG14 is a schematic diagram of the exploded structure of a rotor and a planetary gear set in an electronic mechanical brake device provided in an embodiment of the present application;

[0061] FIG15 is a schematic diagram of the exploded structure of a feeding mechanism at a support cylinder in an electronic mechanical braking device provided in an embodiment of the present application;

[0062] FIG16 is a schematic diagram of the exploded structure of a feeding mechanism in an electromechanical braking device according to an embodiment of the present application;

[0063] FIG17 is a simplified structural diagram of another embodiment of a housing and internal components of an electronic mechanical brake device provided in an embodiment of the present application;

[0064] FIG18 is a simplified structural diagram of another embodiment of a housing and internal components of an electronic mechanical brake device provided in an embodiment of the present application;

[0065] FIG19 is a schematic diagram of the exploded structure of a locking mechanism in an electromechanical brake device according to an embodiment of the present application;

[0066] FIG20 is a schematic cross-sectional view of another embodiment of a locking mechanism in an electronic mechanical brake device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0067] The technical solutions in the embodiments of the present application will be described below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present application, not all of them. Based on the embodiments of the present application, all other embodiments obtained by ordinary technicians in this field without making any creative work are within the scope of protection claimed in this application.

[0068] The present application provides an electronic mechanical brake device with an embedded screw, which includes a housing, a brake motor, a reducer and a screw. The brake motor is used to drive the screw through the reducer to drive the friction plate, wherein: the housing is used to accommodate the stator, rotor, planetary gear set of the reducer, and the screw of the brake motor; the stator and the planetary gear set are arranged along the axial direction of the brake motor, and the planetary gear set is used to transmit and connect the rotor and the screw; the stator, rotor and screw are coaxially arranged, and the screw is at least partially embedded in the center hole of the stator or rotor.

[0069] The electronic mechanical brake device of the present application embeds at least part of the lead screw in the center hole of the stator or rotor, compressing the axial size of the electronic mechanical brake device along the brake motor. While ensuring reliable braking of the electronic mechanical brake device, the overall volume of the electronic mechanical brake device is reduced to achieve miniaturization.

[0070] This application provides an electromechanical braking system comprising at least one friction plate and the aforementioned electromechanical braking device. The electromechanical braking device is configured to drive the at least one friction plate to move axially along a brake motor to brake a wheel. The electromechanical braking system is compact and can fit comfortably around a wheel.

[0071] The present application provides a vehicle comprising wheels and the aforementioned electromechanical braking system. The axial direction of the brake motor in the electromechanical braking system is parallel to the axial direction of the wheel, and the friction pads in the electromechanical braking system are configured to move toward the brake discs of the wheels to brake the vehicle. The electromechanical braking system of the vehicle in the present application is relatively compact, facilitating the layout of the vehicle's interior space.

[0072] The vehicle of the present application includes wheels and a frame, wherein the wheels are rotatably connected to the frame to drive the vehicle. The electronic mechanical braking system of the present application is fixed to the frame and located at the wheels, and the electronic mechanical braking system brakes the wheels through the action of an internal mechanism.

[0073] Please refer to FIG1 for a schematic diagram of the appearance structure of the vehicle wheel provided in an embodiment of the present application.

[0074] As shown in Figure 1 , wheel 1001 is equipped with a brake disc 1002, which is coaxially fixed to the hub of wheel 1001. As wheel 1001 rotates relative to the vehicle frame, brake disc 1002 rotates synchronously with wheel 1001 relative to the vehicle frame. In the diagram of Figure 1 , the outer diameter of brake disc 1002 is smaller than the inner diameter of the inner rim of the wheel, and brake disc 1002 is accommodated within the inner rim of wheel 1001.

[0075] The electronic mechanical braking system 200 provided in the present application is fixed to a vehicle frame (not shown). The electronic mechanical braking system 200 at least partially extends into the inner ring of the wheel 1001 and cooperates with the brake disc 1002 to brake the wheel 1001 .

[0076] Please refer to FIG2 for a schematic cross-sectional structure diagram of a vehicle wheel provided in an embodiment of the present application.

[0077] As shown in Figure 2, the electronic mechanical brake system 200 of the present application includes a caliper frame 201, a friction plate 202, and the electronic mechanical brake device 100 provided in the present application. The caliper frame 201 is fixedly connected to the vehicle frame, and the electronic mechanical brake device 100 is slidably connected to the caliper frame 201. In some embodiments, the electronic mechanical brake device 100 and the caliper frame 201 are slidably connected via a through hole and a sliding rod. That is, the electronic mechanical brake device 100 is provided with one of the through hole and the sliding rod, and the caliper frame 201 is provided with the other of the through hole and the sliding rod. The relative sliding between the electronic mechanical brake device 100 and the caliper frame 201 is achieved by the axial sliding of the sliding rod in the through hole.

[0078] It should be noted that the sliding direction of the electromechanical brake device 100 relative to the caliper frame 201 is parallel to the axial direction of the brake disc 1002. Corresponding to the above-mentioned embodiment of the through hole and the slide rod, the axial direction of the through hole and the axis of the slide rod are respectively parallel to the axial direction of the brake disc 1002.

[0079] There are two friction plates 202, arranged axially on either side of the brake disc 1002. The two friction plates 202 face opposite outer surfaces of the brake disc 1002. The electromechanical brake device 100, through internal mechanism operation and sliding relative to the caliper frame 201, pushes the two friction plates 202 toward each other and into contact with the opposite outer surfaces of the brake disc 1002, generating friction to brake the disc 1002.

[0080] Please refer to FIG. 3 , which shows a schematic cross-sectional structure of an electronic mechanical braking device 100 according to an embodiment of the present application.

[0081] As shown in FIG3 , the electronic mechanical brake device 100 of the present application includes a brake caliper 10, a housing 20, a brake motor 30, and a reducer 40. The brake caliper 10 is slidably connected to the caliper frame 201 and slides axially relative to the caliper frame 201 along the brake disc 1002. The housing 20 is fixedly connected to the brake caliper 10, and the inner cavity of the housing 20 is used to accommodate at least the brake motor 30 and the reducer 40. The reducer 40 is used to transmit and connect the brake caliper 10 and the brake motor 30. The brake motor 30 is used to drive the reducer 40 to rotate, thereby driving the brake caliper 10 to push the friction plate 202.

[0082] The brake caliper 10 includes a caliper 11 and a feed mechanism. Please refer to Figure 4 for details. The caliper 11 is generally U-shaped and includes a main body 111, a pusher 112, and a connecting portion 113. The main body 111 and the pusher 112 are arranged on either side of the brake disc 1002 along the axial direction of the brake disc 1002. The main body 111 and the pusher 112 are also arranged on either side of the two friction plates 202 along the axial direction of the brake disc 1002. In other words, the pusher 112, one friction plate 202, the brake disc 1002, the other friction plate 202, and the main body 111 are arranged in sequence along the axial direction of the brake disc 1002. The connecting portion 113 is located radially outside the brake disc 1002 and is used to securely connect the main body 111 and the pusher 112.

[0083] In one embodiment, the friction plate 202 located on the side of the brake disc 1002 close to the main body 111 is slidably connected to the main body 111. In one embodiment, the friction plate 202 located on the side of the brake disc 1002 close to the pushing portion 112 is fixedly connected to the pushing portion 112.

[0084] The main body 111 is also used for sliding connection to the caliper frame 201. The feeding mechanism is accommodated in the inner cavity of the main body 111. The shell 20 is fixed to the side of the main body 111 away from the pushing portion 112. In some embodiments, the shell 20 and the caliper 11 are an integral structure. Specifically, the shell and the main body 111 of the caliper 11 are an integral structure. In this case, the inner cavity of the shell 20 can be regarded as the inner cavity of the main body 111. That is, the inner cavity of the main body 111 is used to accommodate the brake motor 30, the reducer 40 and at least part of the feeding mechanism. The feeding mechanism is used to transmit and connect the reducer 40 and the friction plate 202 located on one side of the main body 111. In other embodiments, the main body 111 and the shell 20 can be separately arranged and fixedly connected, and the main body 111 and the shell 20 respectively leave space for the feeding mechanism to move, allowing the feeding mechanism to push the friction plate 202 located on one side of the main body 111.

[0085] The feed mechanism includes a lead screw 12 and a threaded sleeve 13. The threaded sleeve 13 is coaxially sleeved on the outside of the lead screw 12, and the lead screw 12 is used to coaxially transmit the output shaft of the reducer 40. The output shaft of the reducer 40 drives the lead screw 12 to rotate, thereby driving the threaded sleeve 13 to slide. At this time, the end of the lead screw 12 facing the reducer 40 can be regarded as the input shaft of the feed mechanism.

[0086] Specifically, the outer circumference of the lead screw 12 and the inner circumference of the threaded sleeve 13 are provided with mating threads. When the lead screw 12 is driven by the reducer 40 to rotate along its own axis, the lead screw 12 can drive the threaded sleeve 13 to slide along the axis of the lead screw 12. On the side of the threaded sleeve 13 away from the reducer 40, the threaded sleeve 13, a friction plate 202, and the brake disc 1002 are arranged in sequence along the axis of the lead screw 12. By driving the threaded sleeve 13 to slide along the axis of the lead screw 12, the lead screw 12 can drive the friction plate 202 to move relative to the brake disc 1002.

[0087] It can be understood that when the brake motor 30 rotates forward, the reducer 40 drives the screw 12 to rotate forward along its own axis, the screw sleeve 13 slides along the axis of the screw 12 toward the brake disc 1002, and drives the friction plate 202 to contact the brake disc 1002 to achieve braking; when the brake motor 30 flips over, the reducer 40 drives the screw 12 to reverse along its own axis, the screw sleeve 13 slides along the axis of the screw 12 toward the direction away from the brake disc 1002, and the friction plate 202 and the brake disc 1002 are released.

[0088] In some embodiments, a separation spring (not shown in the figure) is further provided between the two friction plates 202, and the opposite ends of the separation spring respectively abut against the two friction plates 202. The separation spring is used to provide an elastic force for the two friction plates 202 to move away from each other along the axial direction of the screw 12, so as to ensure that after the screw sleeve 13 slides away from the brake disc 1002, the two friction plates 202 respectively release contact with the brake disc 1002.

[0089] In some embodiments, balls (not shown) may be disposed between the lead screw 12 and the screw sleeve 13. Multiple balls may be provided, and the balls are positioned between the outer threads of the lead screw 12 and the inner threads of the screw sleeve 13. The balls serve to reduce friction between the lead screw 12 and the screw sleeve 13, thereby improving the transmission efficiency of the electronic mechanical brake device 100.

[0090] Please refer to FIG. 5 for a schematic cross-sectional view of the interior of the housing 20 of the electronic mechanical brake device 100 provided in an embodiment of the present application.

[0091] As shown in Figure 5, the brake motor 30 includes a stator 31 and a rotor 32. The stator 31 and rotor 32 are coaxially arranged along the radial direction of the brake motor 30. The stator 31 is used to drive the rotor 32 to rotate and output power. In some embodiments, the brake motor 30 may further include a motor shaft, which is fixed to the rotor 32 and is drivingly connected to the reducer 40. The brake motor 30 transmits power to the reducer 40 via the motor shaft.

[0092] In the embodiment shown in FIG5 , the brake motor 30 is an inner rotor motor, in which the stator 31 is coaxially sleeved on the outside of the rotor 32, and the rotor 32 is located within the center hole of the stator 31. In this case, the housing 20 (the inner cavity of the caliper 11) is used to fix the stator 31, and the stator 31 drives the rotor 32 to rotate within the center hole of the stator 31. In other embodiments, the brake motor 30 can be an outer rotor motor, in which the rotor 32 is coaxially sleeved on the outside of the stator 31, and the stator 31 is located within the center hole of the rotor 32. In this case, a support tube structure is provided within the housing 20 (the inner cavity of the caliper 11), which is used to fix the stator 31, and the stator 31 drives the rotor 32 to rotate outside the stator 31.

[0093] The reducer 40 includes an input shaft 41, an output shaft 42, and a gear set. The input shaft 41 and the output shaft 42 are connected by a gear set. The input shaft 41 is used to transmit and connect the brake motor 30, and the output shaft 42 is used to transmit and connect the brake caliper 10. Specifically, the input shaft 41 of the reducer 40 is used to transmit the rotor 32 of the brake motor 30. In some embodiments, the input shaft 41 is used to coaxially transmit the motor shaft 33 of the brake motor 30. As shown in the figure, in an embodiment of the present application, there are multiple motor shafts 33 of the brake motor 30, and the multiple motor shafts 33 are evenly distributed on the rotor 32 along the circumference. The number of input shafts 41 is also multiple, and each input shaft 41 is coaxially transmitted with a motor shaft 33. Among them, the input shaft 41 can also be an integrated structure with the motor shaft 33 to reduce the overall volume of the electronic mechanical brake device 100.

[0094] The output shaft 42 of the reducer 40 is used to coaxially drive the lead screw 12 of the feed mechanism. A gear set is used to adjust the rotational speed. In the embodiment of the present application, the axis of the input shaft 41 and the axis of the output shaft 42 of the reducer 40 are aligned radially with respect to the brake motor 30. The gear set can be implemented as a planetary gear set 43. The planetary gear set 43 has a relatively compact structure and can provide a large transmission ratio, which facilitates the miniaturization of the electronic mechanical brake device 100 of the present application.

[0095] The following describes in detail the workflow of the electronic mechanical braking system 200 of the present application during the vehicle braking process:

[0096] When the vehicle needs to brake, the stator 31 of the brake motor 30 drives the rotor 32 to rotate forward. The rotor 32 drives the input shaft 41 of the transmission-connected reducer 40 to rotate synchronously around the axis of the brake motor 30. The input shaft 41 drives the output shaft 42 to rotate forward through a gear train. The output shaft 42 drives the lead screw 12 in the transmission-connected feed mechanism to rotate forward synchronously. The feed mechanism is used to convert the rotation of the lead screw 12 into a sliding motion of the screw sleeve 13, that is, the lead screw 12 drives the screw sleeve 13 to slide along the axis of the lead screw 12. The sliding direction of the screw sleeve 13 is toward the brake disc 1002, and the screw sleeve 13 pushes a nearby friction plate 202 to move toward the brake disc 1002, and causes the friction plate 202 to contact the brake disc 1002 to generate friction.

[0097] After the friction plate 202 near the screw sleeve 13 contacts and abuts the brake disc 1002, the stator 31 of the brake motor 30 continues to drive the rotor 32 in forward rotation. Through the same power transmission path described above, the screw sleeve 13 slides axially along the lead screw 12. Because the brake disc 1002 is fixed in position, the screw sleeve 13, friction plate 202, and brake disc 1002 abut each other in sequence. The screw sleeve 13 receives the opposing thrust from the brake disc 1002, and the axial sliding motion of the screw sleeve 13 relative to the lead screw 12 is converted into a sliding motion in which the screw sleeve 13 pushes the caliper 11 in the opposite direction relative to the caliper frame 201. That is, after the friction plate 202 near the screw sleeve 13 contacts and abuts the brake disc 1002, the axial dimension of the feed mechanism further increases under the action of the brake motor 30, pushing the caliper 11 in the opposite direction relative to the caliper frame 201 away from the brake disc 1002. The housing 20 slides synchronously with the caliper 11 in the direction away from the brake disc 1002.

[0098] The sliding movement of the caliper 11 away from the brake disc 1002 can drive the pusher 112 to simultaneously slide toward the brake disc 1002. Because the pusher 112 is located on the side of the brake disc 1002 facing away from the housing 20, the pusher 112 slides toward the brake disc 1002. That is, after the friction plate 202 near the threaded sleeve 13 contacts and abuts the brake disc 1002, the feed mechanism further drives the pusher 112 to slide toward the brake disc 1002. The pusher 112 then drives the other friction plate 202 on the same side to simultaneously slide toward the brake disc 1002, causing the other friction plate 202 to contact and generate friction.

[0099] Thus, through the internal mechanism of the electronic mechanical brake device 100, the friction plates 202 located on both sides of the brake disc 1002 can be driven to slide toward each other and contact the two opposite outer surfaces of the brake disc 1002 respectively, generating friction to brake the brake disc 1002 and achieve vehicle braking.

[0100] After braking is complete, the stator of the brake motor 30 drives the rotor 32 in reverse rotation. The rotor 32, in turn, drives the input shaft 41 and output shaft 42 of the reducer 40, as well as the lead screw 12 of the feed mechanism, to rotate in a synchronous manner. The reverse rotation of the lead screw 12 causes the threaded sleeve 13 to slide away from the brake disc 1002, thereby increasing the distance between the two friction plates 202. The release spring releases the two friction plates 202 from the brake disc 1002, allowing the wheel 1001 to continue rotating and driving the vehicle.

[0101] In some embodiments, a return spring (not shown in the figure) can also be provided between the caliper 11 and the caliper frame 201. The return spring is used to drive the caliper 11 to slide relative to the caliper frame 201 toward the brake disc 1002, so as to drive the pushing portion 112 to slide toward the direction away from the brake disc 1002, thereby ensuring that the two friction plates 202 are reliably separated from the brake disc 1002.

[0102] Therefore, after braking is completed, the internal mechanism of the electronic mechanical brake device 100 can drive the friction plates 202 located on both sides of the brake disc 1002 to slide opposite to each other and release contact with the two opposite outer surfaces of the brake disc 1002, so that the wheel 1001 can continue to rotate and drive the vehicle to move.

[0103] In one embodiment, the electromechanical brake device 100 includes a circuit board 50. The circuit board 50 holds a drive circuit, which drives the brake motor 30. The circuit board 50 can be housed within the inner cavity of the housing 20 along with the brake motor 30. This shortens the signal transmission distance from the drive circuit to the brake motor 30 and simplifies the internal wiring layout of the electromechanical brake device 100. Furthermore, the housing 20 provides a reliable seal and protective protection for the circuit board 50.

[0104] In one embodiment, the electromechanical brake device 100 includes a position sensor. The position sensor is used to detect the rotation angle of the brake motor 30 and thereby adjust the braking force of the electromechanical brake device 100. The position sensor includes a stator and a rotor. The stator of the position sensor can be fixed to the housing 20, and the rotor of the position sensor can be coaxially driven with the motor shaft of the brake motor 30 or the drive shaft of the reducer 40. The stator of the position sensor can be directly fixed to the housing 20, or it can be fixed to the circuit board 50 and indirectly fixed to the housing 20 via the circuit board 50; the rotor of the position sensor can be coaxially driven with the motor shaft of the brake motor 30 or the output shaft 42 of the reducer 40.

[0105] The stator and rotor of the position sensor work together to detect the rotational angle of the motor shaft of the brake motor 30 and the output shaft 42 of the reducer 40 within the inner cavity of the caliper 11. The position sensor is also in communication with the drive circuit on the circuit board 50. The drive circuit receives the angle signal detected by the position sensor, calculates the rotational angle of the rotor 32 in the brake motor 30, and thereby adjusts the braking force of the electronic mechanical brake device 100, thereby adjusting the braking force of the vehicle.

[0106] In one embodiment, the electronic mechanical brake device 100 includes a locking mechanism. The locking mechanism is used to lock or release the motor shaft of the brake motor 30, or the locking mechanism is used to lock or release the drive shaft of the reducer 40, and enables the electronic mechanical brake device 100 of the present application to also have a parking function. Specifically, part of the locking mechanism is fixed to the housing 20, and the other part acts on the motor shaft of the brake motor 30 or the drive shaft of the reducer 40. When the friction plate 202 of the electronic mechanical brake system 200 is in contact with the brake disc 1002, the motor shaft of the brake motor 30 or the drive shaft of the reducer 40 can be locked by the locking mechanism to maintain the contact state of the friction plate 202 with the brake disc 1002, and the brake disc 1002 no longer rotates, and the vehicle enters the parking state.

[0107] Please refer to Figures 6 to 8. Figure 6 shows the exterior structure of the housing 20 in the electronic mechanical brake device 100 of the present application; Figure 7 shows the structure of the housing 20 after decomposition and its internal components; and Figure 8 shows a simplified structural diagram of the housing 20 and its internal components.

[0108] In the electronic mechanical brake device 100 of the present application, the housing 20 is used to accommodate the stator 31, rotor 32, lead screw 12 of the brake motor 30, and the planetary gear set 43 of the reducer 40. The rotor 32 of the brake motor 30 and the planetary gear set 43 are arranged along the axial direction of the brake motor 30, and the planetary gear set 43 is used to drive the connection between the rotor 32 and the lead screw 12.

[0109] In the illustrated embodiment, the housing 20 also houses a circuit board 50 and a position sensor 70. The housing 20 includes a partition 21. The stator 31, rotor 32, lead screw 12 of the brake motor 30, and the planetary gear set 43 of the reducer 40 are located on one side of the partition 21, while the circuit board 50 and the position sensor 70 are located on the other side. Because the circuit board 50 carries the drive circuitry, and the brake motor 30, feed mechanism, and reducer 40 may each contain cooling oil or lubricating oil, the partition 21 is placed between the circuit board 50 and the brake motor 30, planetary gear set 43, and feed mechanism, providing a sealed and protective seal.

[0110] In the illustrated embodiment, the position sensor 70 and the circuit board 50 are located on the same side of the partition 21. In other embodiments, the position sensor 70 may also be located on the side of the partition 21 facing away from the circuit board 50. Similarly, when the electromechanical brake device 100 includes a locking mechanism, the locking mechanism and the circuit board 50 may be located on the same side of the partition 21, or the locking mechanism and the circuit board 50 may be located on opposite sides of the partition 21. The positions of the locking mechanism and the position sensor 70 can be matched based on their specific structures and spatial arrangements.

[0111] In the illustrated embodiment, the brake motor 30 is an inner rotor motor, i.e., the stator 31 is coaxially sleeved on the outside of the rotor 32, and the housing 20 is used to secure the stator 31. The rotor 32 includes a central hole, and the lead screw 12 of the electronic mechanical brake device 100 of the present application is at least partially embedded in the central hole of the rotor 32. In the illustrated embodiment, the lead screw 12 and the threaded sleeve 13 are both at least partially embedded in the central hole of the rotor 32. In one embodiment, the planetary gear set 43 is also at least partially embedded in the central hole of the stator 31.

[0112] As a result, the stator 31 and rotor 32 of the electronic mechanical brake device 100 of the present application are sleeved on the outside of the lead screw 12 along the radial direction of the brake motor 30, forming a structure in which the lead screw 12 is partially embedded in the brake motor 30. This structure compresses the axial dimension of the electronic mechanical brake device 100 along the brake motor 30. While ensuring reliable braking of the electronic mechanical brake device 100, it also compresses the overall volume of the electronic mechanical brake device 100, achieving miniaturization. The electronic mechanical brake system 200 of the present application also has a smaller overall volume, which can effectively utilize the wheel side space of the vehicle. The vehicle of the present application also has a larger internal space, which is beneficial for the arrangement of the remaining components of the vehicle.

[0113] It is understood that when the brake motor is an outer rotor motor, that is, the rotor 32 is coaxially sleeved outside the stator 31, the lead screw 12 can be at least partially embedded in the center hole of the stator 31, and the above-mentioned reducer 40 can also be partially embedded in the brake motor 30. Under the premise of ensuring reliable braking of the electronic mechanical brake device 100, the overall volume of the electronic mechanical brake device 100 is compressed to achieve miniaturization.

[0114] On the other hand, because the threaded sleeve 13 is radially sleeved on the outside of the lead screw 12, the brake motor 30 at least partially accommodates the lead screw 12, which also means that the brake motor 30 at least partially accommodates the threaded sleeve 13. In other words, the threaded sleeve 13 is at least partially embedded in the center hole of the stator 31 or rotor 32. Alternatively, the feed mechanism is at least partially embedded in the center hole of the brake motor 30.

[0115] Please refer to Figures 9 to 12. Figure 9 shows the appearance and structure of the brake motor 30 in the electronic mechanical brake device 100 of the present application; Figure 10 shows the exploded structure of the brake motor 30; Figure 11 shows the appearance and structure of the rotor 32 in the brake motor 30; and Figure 12 shows the exploded structure of the rotor 32 in the brake motor 30.

[0116] As shown in FIG9 , the brake motor 30 of the electronic mechanical brake device 100 of the present application includes at least two motor shafts 33. At least two motor shafts 33 are fixed to the rotor 32 at equal intervals along the circumference of the brake motor 30. Each motor shaft 33 is used to drive the connection between the rotor 32 and a planetary gear 432 in the planetary gear set 43. The rotor 32 drives the planetary gear 432 through the motor shaft 33 and drives the output shaft 42 of the reducer 40 to rotate. The motor shaft 33 can be regarded as the input shaft 41 in the planetary gear set 43, or it can be understood that the motor shaft 33 and the input shaft 41 are an integral structure.

[0117] Each motor shaft 33 of the brake motor 30 is equidistant from the axis of the brake motor 30. When the stator 31 of the brake motor 30 drives the rotor 32 to rotate, the multiple motor shafts 33 rotate around the axis of the brake motor 30. The planetary gear 432 connected to the motor shaft 33 is able to rotate relative to the sun gear 431 of the planetary gear set 43. The planetary gear 432 can drive the sun gear 431 of the planetary gear set 43 to rotate, and the sun gear 431 in turn drives the output shaft 42 or the lead screw 12 to rotate synchronously, thereby achieving the transmission ratio of the reducer 40. That is, the rotor 32 of the brake motor 30 drives the planetary gear set 43 by driving the planetary gear 432 to rotate, and the planetary gear set 43 is able to drive the lead screw 12 coaxially.

[0118] In one embodiment, the motor shaft 33, the lead screw 12, and the caliper 11 are arranged in sequence along the axial direction of the brake motor 30. That is, the motor shaft 33 is located on the side of the lead screw 12 away from the caliper 11. The power of the planetary gear set 43 is input from the side of the lead screw 12 away from the caliper 11, facilitating power output from the lead screw 12 toward the caliper 11.

[0119] Referring to Figures 11 and 12 , in one embodiment, the rotor 32 of the brake motor 30 includes a rotor support 321 and a plurality of magnetic plates 322. The rotor support 321 is cylindrical, and the motor shaft 33 is fixed to the end of the rotor support 321. Along the circumference of the rotor support 321, the plurality of magnetic plates 322 are evenly arranged and fixed to the circumferential surface of the rotor support 321 facing the stator of the brake motor 30.

[0120] Specifically, in the schematic diagrams of Figures 11 and 12 , rotor bracket 321 comprises two parts: one portion forming the main body of rotor bracket 321, and the other portion, which is sleeved around the main body of rotor bracket 321 and has multiple hollow areas. Each magnetic sheet 322 is embedded within each hollow area to secure it to the outer circumference of rotor bracket 321. In other embodiments, magnetic sheets 322 can also be surface-mounted, directly attached to the outer circumference of rotor bracket 321.

[0121] The winding in the form of magnetic sheet 322 is easy to manufacture, and by controlling the thickness of magnetic sheet 322 and the wall thickness of rotor bracket 321, the radial dimension of rotor 32 can be reduced, further reducing the radial dimension of brake motor 30, thereby miniaturizing electronic mechanical brake device 100. Furthermore, the reduced radial dimension of rotor 32 facilitates the insertion of lead screw 12 and threaded sleeve 13 into the center hole of rotor 32 or stator 31.

[0122] It should be noted that in the schematic diagrams of Figures 11 and 12 , the brake motor 30 is an inner rotor motor. In this case, the outer circumference of the rotor bracket 321 faces the stator 31, and the multiple magnetic sheets 322 are attached to the outer circumference of the rotor bracket 321. In contrast, if the brake motor 30 is an outer rotor motor, the inner circumference of the rotor bracket 321 faces the stator 31, and the multiple magnetic sheets 322 need to be attached to the inner circumference of the rotor bracket 321 to ensure reliable operation of the brake motor 30.

[0123] Furthermore, along the axial direction of the brake motor 30, the rotor 32 is provided with two support bearings 94a and 94b. One support bearing 94a is sleeved on the outer circumference of the rotor support 321, while the other support bearing 94b is embedded in the inner circumference of the rotor support 321. These two bearings 94a and 94b support the rotor 32 from two circumferential surfaces of the rotor support 321, thereby ensuring smooth rotation of the rotor 32 and improving the braking efficiency of the electromechanical brake device 100.

[0124] In one embodiment, at least one support bearing (shown as support bearing 94 a in FIG. 11 and FIG. 12 ) is a needle bearing. The radial dimension of the needle bearing is relatively small, which helps to control the overall volume of the electromechanical brake device 100.

[0125] Please refer to Figure 5, Figure 13 and Figure 14. Figure 13 is a schematic diagram of the internal structure of the rotor 32 and the planetary gear set 43, and Figure 14 is a schematic diagram of the exploded structure of the rotor 32 and the planetary gear set 43.

[0126] As shown in Figures 12 and 13, in one embodiment, the planetary gear set 43 includes a two-stage planetary gear train. The two-stage planetary gear train is axially spaced apart along the output shaft 42 of the reducer 40 and is drivingly connected to increase the transmission ratio of the planetary gear set 43. It is understood that in other embodiments, the planetary gear set 43 may include only one stage of planetary gear train, or may include three or more stages of planetary gear trains, depending on the transmission ratio requirements of the reducer 40.

[0127] Each stage of the planetary gear train includes a sun gear 431 and a planetary gear 432. Taking the planetary gear train far away from the screw 12 as an example, in this planetary gear train, the sun gear 431 is fixed to the housing 20, and the axis of the sun gear 431 coincides with the axis of the output shaft 42 of the reducer 40. There are multiple planetary gears 432, and multiple planetary gears 432 are engaged with the outer periphery of the sun gear 431. The multiple planetary gears 432 are respectively connected to an input shaft 41 (i.e., a motor shaft 33) for rotation. At this time, the rotor 32 and the multiple motor shafts 33 (i.e., multiple input shafts 41) can form the structure of the planetary carrier in the planetary gear train. The planetary carrier is used to drive the next stage of the planetary gear train to move.

[0128] Specifically, each motor shaft 33 (i.e., input shaft 41) is used to rotate and connect two planetary gears 432. The two planetary gears 432 belong to two planetary gear systems. That is, the motor shaft 33 is used to transmit and connect the rotor 32 and the two planetary gears 432. The planetary gears 432 in the two planetary gear systems rotate synchronously, and the sun gear 431 in the planetary gear system close to the screw 12 (the sun gear 431 of the next-level planetary gear system) is driven by the outer planetary gear 432 (of the next-level planetary gear system) to rotate synchronously. The axis of the sun gear 431 in the planetary gear system close to the screw 12 coincides with the axis of the output shaft 42. The sun gear 431 in the planetary gear system close to the screw 12 can drive the output shaft 42 to rotate coaxially, thereby driving the screw 12 to rotate coaxially.

[0129] Thus, in the planetary gear set 43 of the reducer 40, the planetary gears 432 of the two-stage planetary gear trains are coaxially driven. The sun gear 431 of the first-stage planetary gear train is fixed to the housing 20, and the sun gear 431 of the second-stage planetary gear train is coaxially driven with the output shaft 42. The multiple motor shafts 33 (input shaft 41) fixed to the rotor 32 form the planetary carrier structure between the two planetary gear trains. When the rotor 32 drives the multiple motor shafts 33 to rotate, the intermeshing planetary gears 432 and sun gear 431 can achieve a single-stage reduction effect. The planetary gear set 43 of the reducer 40 realizes the transmission connection of the two-stage planetary gear trains, thereby achieving a higher transmission ratio.

[0130] In some embodiments, each stage of the planetary gear train may further include a ring gear (not shown). The ring gear is fixed to the inner circumference of the housing 20 and is sleeved around the outer periphery of the plurality of planetary gears 432. The ring gear can be used to support the planetary gears 432 of each stage of the planetary gear train, thereby ensuring smoother rotation of the planetary gear set 43 and improving transmission efficiency.

[0131] Please refer to Figures 5 and 7. In one embodiment, the housing 20 includes a support tube 22. The support tube 22 is cylindrical, and the support tube 22 is located in the inner cavity of the housing 20 and is fixedly connected to the main body of the housing 20. The axis of the support tube 22 coincides with the axis of the brake motor 30. Along the radial direction of the brake motor 30, the support tube 22 is located between the lead screw 12 and the rotor 32 of the brake motor 30. The support tube 22 is used to accommodate the lead screw 12 and the screw sleeve 13 of the feed mechanism. The stator 31 and the rotor 32 of the brake motor 30 are accommodated between the support tube 22 and the main body of the housing 20.

[0132] For details, please refer to Figures 15 and 16. Figure 15 shows the exploded structure of the feeding mechanism at the support cylinder 22, and Figure 16 shows the exploded structure of the feeding mechanism.

[0133] The inner circumference of support tube 22 is used to support and hold screw sleeve 13. Along the radial direction of brake motor 30, support tube 22 is coaxial with stator 31, rotor 32 and lead screw 12. Wherein screw sleeve 13 is sleeved on lead screw 12 outside, therefore along the radial direction of brake motor 30, stator 31, rotor 32, support tube 22, screw sleeve 13 and lead screw 12 are coaxially arranged successively (referring to Figure 8).And for the embodiment that brake motor 30 is outer rotor motor, then rotor 32, stator 31, support tube 22, screw sleeve 13 and lead screw 12 are coaxially arranged successively (referring to Figure 17).Axially along the brake motor 30, support tube 22 stretches into the gap between the rotor 32 of brake motor 30 and screw sleeve 13, and support tube 22 is used to guide screw sleeve 13 to slide axially along output shaft 42.

[0134] Please refer to Figure 8 . In one embodiment, when the brake motor 30 is an inner rotor motor, the inner circumference of the housing 20 is used to fix the outer circumference of the stator 31, and the center hole of the stator 31 is used to accommodate the rotor 32. The rotor 32 can rotate relative to the outer circumference of the support tube 22, with a gap remaining between the rotor 32 and the outer circumference of the support tube 22. A support bearing (shown as support bearing 94b in Figure 12) on the rotor 32 can abut against the outer circumference of the support tube 22, that is, a support bearing 94b can be positioned between the rotor 32 and the outer circumference of the support tube 22. The inner ring of the support bearing 94b is fixed to the outer circumference of the support tube 22, and the outer ring of the support bearing 94b is fixed to the inner circumference of the rotor 32. The support bearing 94b supports the rotor 32, ensuring smoother rotation of the rotor 32 relative to the support tube 22. In one embodiment, along the axial direction of the brake motor 30, the support bearing 94a and the support bearing 94b are located at opposite ends of the rotor 32. The two support bearings 94 a and 94 b can support the rotor 32 from both sides of the rotor 32 , further improving the rotational stability of the rotor 32 and enhancing the transmission efficiency of the electronic mechanical brake device 100 .

[0135] In another embodiment, when the brake motor 30 is an external rotor motor, as shown in Figure 17 , the outer circumferential surface of the support cylinder 22 also serves to secure the inner circumferential surface of the stator 31, and the center hole of the rotor 32 is used to accommodate the stator 31. In this case, the rotor 32 can rotate relative to the inner circumferential surface of the housing 20, with a gap remaining between the rotor 32 and the inner circumferential surface of the housing 20. In this case, a support bearing 94a is provided between the rotor 32 and the inner circumferential surface of the housing 20. The support bearing 94a serves to enhance the rotational stability of the rotor 32 and ensure the transmission efficiency of the electromechanical brake device 100.

[0136] In one embodiment, the outer circumferential surface of the screw sleeve 13 is in at least partial contact with the inner circumferential surface of the support tube 22, and a stop-rotation protrusion and a stop-rotation notch that cooperate with each other are provided between the outer circumferential surface of the screw sleeve 13 and the inner circumferential surface of the support tube 22. The stop-rotation protrusion extends into the stop-rotation notch along the radial direction of the screw sleeve, and the stop-rotation protrusion and the stop-rotation notch abut against each other to limit the rotation of the screw sleeve 13 in the support tube 22.

[0137] Specifically, as shown in Figure 15, the outer circumferential surface of the screw sleeve 13 is provided with a rotation-stopping notch 131. The rotation-stopping notch 131 is represented by a plane formed on the outer circumferential surface of the screw sleeve 13. Correspondingly, the inner circumferential surface of the support tube 22 can be provided with a rotation-stopping protrusion (not shown), the position of the rotation-stopping protrusion being aligned with the plane of the rotation-stopping notch 131, and the rotation-stopping protrusion being used to abut the plane of the rotation-stopping notch 131 to limit the rotation of the screw sleeve 13 relative to the support tube 22.

[0138] As will be appreciated, the screw sleeve 13 and the lead screw 12 are meshed with each other, and rotation of the lead screw 12 may drive synchronous rotation of the screw sleeve 13. The rotation of the screw sleeve 13 within the support cylinder 22 may affect the axial sliding distance of the screw sleeve 13, resulting in inadequate braking of the electronic mechanical brake device 100. Therefore, the provision of the anti-rotation notch 131 and the anti-rotation protrusion can ensure that the rotation of the lead screw 12 can drive the axial displacement of the screw sleeve 13, thereby ensuring reliable braking of the electronic mechanical brake device 100.

[0139] On the other hand, limiting the rotation of the screw sleeve 13 relative to the support tube 22 can eliminate friction loss caused by the rotation of the screw sleeve 13 in the support tube 22 , thereby improving the braking efficiency of the electronic mechanical brake device 100 .

[0140] It is understandable that the anti-rotation notch 131 can also be set as a groove or other structure, and the anti-rotation protrusion can be set as a plane or convex strip structure. For the electronic mechanical braking device 100 of the present application, the relative rotation of the screw sleeve 13 and the support tube 22 can be limited.

[0141] Correspondingly, the anti-rotation protrusion can also be provided on the outer peripheral surface of the screw sleeve 13, and the anti-rotation notch can be provided on the inner peripheral surface of the support tube 22 to achieve a similar anti-rotation effect.

[0142] In the schematic diagram of Figure 15, the screw sleeve 13 can also be divided into two parts. The two parts of the screw sleeve 13 are arranged adjacent to each other along the axial direction of the lead screw 12. The part of the screw sleeve 13 along the axial direction of the lead screw 12 close to the planetary gear set 43 is used for mutual meshing transmission with the lead screw 12. The part of the screw sleeve 13 along the axial direction of the lead screw 12 close to the friction plate 202 is used to push the friction plate 202. Therefore, the part of the screw sleeve 13 along the axial direction of the lead screw 12 close to the friction plate 202 can be provided with a contact surface 132 facing the friction plate 202. The contact surface 132 is located on one side of the lead screw 12 along the axial direction of the lead screw 12, and the contact surface 132 is located between the lead screw 12 and the friction plate 202. The contact surface 132 can increase the contact area between the screw sleeve 13 and the friction plate 202, ensuring that the screw sleeve 13 reliably pushes the friction plate 202.

[0143] As mentioned above, the electronic mechanical brake device 100 of the present application may include a circuit board 50. In one embodiment, along the axial direction of the brake motor 30, the circuit board 50, the rotor 32 of the brake motor 30, and the planetary gear set 43 of the speed reducer 40 are arranged in sequence, with the circuit board 50 and the planetary gear set 43 located on opposite sides of the rotor 32.

[0144] Specifically, as shown in Figure 17 , the circuit board 50 is positioned on the side of the planetary gear set 43 away from the lead screw 12, avoiding the need for a clearance hole in the circuit board 50 to clear the output shaft 42 of the reducer 40. In one embodiment, the plane of the circuit board 50 is perpendicular to the axial direction of the brake motor 30, thereby shortening the dimension of the electronic mechanical brake device 100 along the axial direction of the brake motor 30.

[0145] Please refer to Figure 18, which illustrates one implementation of the position sensor 70 and the locking mechanism 60 in the housing 20 and its internal components. Specifically, the position sensor 70 of the electronic mechanical brake device 100 includes a stator 71 and a rotor 72. The circuit board 50 is used to fix the stator 71 of the position sensor 70, and the output shaft 42 of the reducer 40 is used to coaxially drive the rotor 72 of the position sensor 70. Specifically, the end of the output shaft 42 toward the circuit board 50 extends toward the circuit board 50, and the rotor 72 of the position sensor 70 can be fixed to the output shaft 42 and aligned with the stator 71 of the position sensor 70 fixed to the circuit board 50. The rotor 72 of the position sensor 70 rotates with the output shaft 42, and the stator 71 of the position sensor 70 is used to detect the rotation angle of the output shaft 42.

[0146] Based on the different working principles of the position sensor 70, the stator 71 and rotor 72 of the position sensor 70 can be aligned in the axial direction of the brake motor 30 or in the radial direction of the brake motor 30. When the stator 71 and rotor 72 of the position sensor 70 are aligned in the axial direction of the brake motor 30, the rotor 72 of the position sensor 70 can be fixed to the end of the output shaft 42 of the reducer 40 facing the circuit board 50, leaving a gap between the stator 71 and rotor 72 of the position sensor 70 along the axial direction of the brake motor 30.

[0147] When the stator 71 and rotor 72 of the position sensor 70 are aligned radially with respect to the brake motor 30, as shown in FIG18 , the stator 71 of the position sensor 70 has an inner hole, the axis of which coincides with the axis of the brake motor 30, and the output shaft 42 of the reducer 40 extends toward the circuit board 50. The end of the output shaft 42 passes through the circuit board 50, the rotor 72 of the position sensor 70 is fixed to the outer circumference of the output shaft 42, and the inner hole of the stator 71 of the position sensor 70 is used to at least partially accommodate the rotor 72 of the position sensor 70. At this point, a gap is left between the stator 71 and the rotor 72 of the position sensor 70 radially with respect to the brake motor 30.

[0148] FIG18 also illustrates a method for implementing a locking mechanism 60. In this implementation, the locking mechanism 60 is arranged along the axial direction of the brake motor 30 on the side of the output shaft 42 away from the brake caliper 10. The locking mechanism 60 is used to lock or release the end of the output shaft 42. Specifically, the locking mechanism 60 includes a clutch 61 and a locking motor 62. The locking motor 62 is fixed in the inner cavity of the housing 20, and the clutch 61 can lock or release the end of the output shaft 42 under the drive of the locking motor 62. The circuit board 50 can also be used to fix the control circuit of the locking motor 62, and the control circuit of the locking motor 62 is used to output AC power to drive the locking motor 62.

[0149] Referring to Figure 19 , the output shaft 42 of the reducer 40 has an inner hole 421 at its end. The clutch 61 includes an inner wheel 611, a movable member 612, a spring 613, and an axially movable member 614. The inner wheel 611 is embedded within the inner hole 421, and the movable member 612 and spring 613 are both received in a groove in the inner wheel 611. One end of the spring 613 abuts against the movable member 612, while the other end abuts against the inner wall of the groove in the inner wheel 611. The spring 613 is used to push the movable member 612 toward the inner wall of the groove on the other side of the inner wheel 611.

[0150] The axially movable member 614 is driven by the locking motor 62 to slide within the housing 20, and the sliding direction of the axially movable member 614 is parallel to the axial direction of the output shaft 42. The axially movable member 614 is driven to extend into or out of the inner hole 421 of the output shaft 42. When the axially movable member 614 extends into the inner hole 421 of the output shaft 42, the axially movable member 614 abuts against the movable member 612 and drives the movable member 612 to slide toward one side of the spring 613. When the axially movable member 614 exits the inner hole 421 of the output shaft 42, the axially movable member 614 releases the movable member 612, and the movable member 612 slides toward the side away from the spring 613 under the action of the spring 613.

[0151] The groove bottom of the inner wheel 611 is tilted, and the movable member 612 switches between two positions, correspondingly changing its radial height relative to the inner wheel 611. When the movable member 612 is at a higher radial height, it abuts against the inner circumference of the inner bore 421 of the output shaft 42, thereby locking the end of the output shaft 42. When the movable member 612 is at a lower radial height, it releases the inner circumference of the inner bore 421 of the output shaft 42, thereby releasing the end of the output shaft 42. Thus, the locking mechanism 60, through the control of the clutch 61 by the locking motor 62, can lock or release the end of the output shaft 42, thereby achieving the parking function.

[0152] In one embodiment, the electronic mechanical brake device 100 may further include a locking bearing 93, which is used to support the output shaft 42 of the reducer 40. For details, please refer to FIG18 . As shown in FIG18 , the locking bearing 93 is disposed on the side of the circuit board 50 near the planetary gear set 43. The inner ring of the locking bearing 93 is fixed to the outer circumferential surface of the output shaft 42, and the outer ring of the locking bearing 93 is fixed to the inner wall of the housing 20. Because the output shaft 42 of the reducer 40 extends a long distance toward the circuit board 50, disposing the locking bearing 93 on the side of the circuit board 50 near the planetary gear set 43 can provide better support for the output shaft 42.

[0153] In other embodiments, the locking mechanism 60 can be coaxially arranged with the output shaft 42 of the reducer 40, and the locking mechanism 60 is used to lock or release the outer peripheral surface of the output shaft 42 of the reducer 40. Specifically, please refer to the schematic diagram of Figure 20. In one embodiment, the locking mechanism 60 includes a sleeve 63, an electromagnetic coil 64 and an axial displacement member 65. The sleeve 63 is used to fix the outer peripheral surface of the output shaft 42, and the electromagnetic coil 64 is sleeved outside the sleeve 63, and the electromagnetic coil 64 is fixed to the housing 20. The circuit board 50 is used to fix the control circuit of the electromagnetic coil 64, and the control circuit of the electromagnetic coil 64 is used to control the conduction or disconnection of the electromagnetic coil 64. The electromagnetic coil 64 is used to drive the axial displacement member 65 to slide toward or away from the sleeve 63 to lock or release the output shaft 42.

[0154] In this embodiment, the axial displacement member 65 and the sleeve 63 are spaced apart in the axial direction of the output shaft 42. A locking structure that engages with each other is provided between the axial displacement member 65 and the sleeve 63 along the radial direction of the brake motor 30. For example, the sleeve 63 may be provided with an inner hole, and the axial displacement member 65 may be driven by the electromagnetic coil 64 to partially slide into the inner hole of the sleeve 63. The portion of the axial displacement member 65 located outside the inner hole of the sleeve 63 may be fixed to the housing 20. The outer circumferential surface of the portion of the axial displacement member 65 that extends into the sleeve 63 engages with the inner circumferential surface of the sleeve 63. The axial displacement member 65 is able to hold the sleeve 63 and, through the sleeve 63, acts on the outer circumferential surface of the output shaft 42, thereby locking the transmission function of the reducer 40 to achieve a parking effect.

[0155] When the parking state needs to be released, the electromagnetic coil 64 is de-energized, and the axial displacement member 65 can withdraw from the inner hole of the sleeve 63 under the action of the telescopic spring 66, thereby releasing the outer peripheral surface of the output shaft 42, and the reducer 40 resumes the transmission function.

[0156] In other embodiments, an inner hole can be provided on the side of the axial displacement member 65 facing the sleeve 63, and the axial displacement member 65 can be slidably mounted on the outer side of the sleeve 63. The inner circumference of the inner hole of the axial displacement member 65 engages with the outer circumference of the sleeve 63, thereby securing the sleeve 63. The axial displacement member 65 acts on the outer circumference of the output shaft 42 through the sleeve 63, locking the transmission function of the speed reducer 40 and achieving the parking effect. When the parking state is to be released, the electromagnetic coil 64 is de-energized, and the axial displacement member 65 slides off the sleeve 63 under the action of the expansion spring 66, thereby releasing the outer circumference of the output shaft 42 and resuming the transmission function of the speed reducer 40.

[0157] The telescopic spring 66 can be implemented by a disc spring, a wave spring, or the like.

[0158] Of course, the above-mentioned embodiments can be applied individually or in combination. The above is the preferred embodiment of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present application. These improvements and modifications are also considered to be within the scope of protection of the present application.

Claims

1. An electromechanical brake device with an embedded lead screw, characterized in that: The electronic mechanical brake device comprises a housing, a brake motor, a reducer and a lead screw, wherein the brake motor is used to drive the lead screw through the reducer to drive the friction plate, wherein: The housing is used to accommodate the stator and rotor of the brake motor, the planetary gear set of the reducer, and the lead screw; The rotor and the planetary gear set are arranged along the axial direction of the brake motor, and the planetary gear set is used for transmission connection between the rotor and the lead screw; The stator, the rotor and the lead screw are coaxially arranged, and the lead screw is at least partially embedded in a center hole of the stator or the rotor.

2. The electromechanical brake device according to claim 1, characterized in that: The electronic mechanical brake device comprises a screw sleeve, which is sleeved on the lead screw. The lead screw is used to rotate with the output shaft and drive the screw sleeve to slide along the axial direction of the output shaft to drive the friction plate.

3. The electromechanical brake device according to claim 2, characterized in that: The electronic mechanical brake device includes a support tube, which is coaxially arranged with the stator, the rotor and the lead screw. The inner circumference of the support tube is used to support the screw sleeve, and the support tube is at least partially embedded in the center hole of the stator or the rotor.

4. The electromechanical brake device according to claim 3, characterized in that: A stop protrusion and a stop notch that cooperate with each other are provided between the outer circumference of the screw sleeve and the inner circumference of the support tube. The stop protrusion extends into the stop notch along the radial direction of the screw sleeve to limit the rotation of the screw sleeve in the support tube.

5. The electromechanical brake device according to any one of claims 2 to 4, characterized in that: The inner circumference of the housing is used to fix the outer circumference of the stator, and the central hole of the stator is used to accommodate the rotor; or, The outer circumferential surface of the support cylinder is used to fix the inner circumferential surface of the stator, and the central hole of the rotor is used to accommodate the stator.

6. The electromechanical brake device according to any one of claims 1 to 5, characterized in that: The brake motor includes at least two motor shafts, which are fixed to the rotor at equal intervals along the circumference of the brake motor. Each motor shaft is used to drive the rotor and the planetary gears in the planetary gear set. The rotor drives the planetary gears through the motor shafts and drives the output shaft of the reducer to rotate.

7. The electromechanical brake device according to claim 6, characterized in that: The planetary gear set includes two planetary gear trains, and the two planetary gear trains are arranged at intervals along the axial direction of the brake motor, wherein: The housing is used to fix the sun gear in the planetary gear system away from the stator, and the output shaft of the reducer is used to coaxially drive another sun gear; Each of the motor shafts is used for transmission connection between the rotor and two planetary gears, and the two planetary gears belong to the two planetary gear trains.

8. The electromechanical brake device according to claim 6, characterized in that: The rotor of the brake motor includes a rotor bracket and a plurality of magnetic sheets. The rotor bracket is cylindrical. The at least two motor shafts are fixed to the rotor bracket. The plurality of magnetic sheets are uniformly surrounded and fixed to the circumferential surface of the rotor bracket facing the stator of the brake motor along the circumference of the rotor bracket.

9. The electromechanical brake device according to any one of claims 1 to 8, characterized in that: The electromechanical brake device comprises a circuit board, the circuit board is used to fix a drive circuit, the drive circuit is used to drive the brake motor, wherein: Along the axial direction of the brake motor, the circuit board, the rotor of the brake motor and the planetary gear set are arranged in sequence, and the circuit board and the planetary gear set are located on opposite sides of the rotor of the brake motor.

10. The electromechanical brake device according to claim 9, characterized in that: The electromechanical brake device comprises a position sensor, which is used to detect the rotation angle of the brake motor. The position sensor comprises a stator and a rotor, wherein: The circuit board is used to fix the stator of the position sensor; The output shaft of the reducer is used for coaxially driving the rotor of the position sensor.

11. The electromechanical brake device according to any one of claims 1 to 10, characterized in that: The end of the output shaft of the reducer away from the screw extends through the center hole of the planetary gear set toward the circuit board, the rotor of the position sensor is fixed to the output shaft of the reducer, and at least a portion of the inner hole of the stator of the position sensor is used to accommodate the rotor of the position sensor.

12. The electromechanical brake device according to any one of claims 1 to 11, characterized in that: The electronic mechanical brake device comprises a locking mechanism, which is used to lock or release the output shaft of the reducer. The locking mechanism is coaxially arranged with the output shaft, and is used to lock or release the output shaft.

13. The electromechanical brake device according to any one of claims 1 to 12, characterized in that: The electronic mechanical brake device comprises a caliper, which is used to connect the at least one friction plate, and the caliper is fixedly connected to the housing along the axial direction of the brake motor.

14. An electromechanical braking system, characterized in that: The invention comprises at least one friction plate and an electronic mechanical braking device as claimed in any one of claims 1 to 13, wherein the electronic mechanical braking device is used to drive the at least one friction plate to move along the axial direction of the brake motor to brake the wheel.

15. A vehicle, characterized in that: It comprises a wheel and an electronic mechanical braking system as claimed in claim 14, wherein the axial direction of the brake motor in the electronic mechanical braking system is parallel to the axial direction of the wheel, and the friction plate in the electronic mechanical braking system is used to move toward the brake disc of the wheel to brake the vehicle.

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