In-wheel motor two-speed transmission system with integrated multiplexed electromechanical brake

Abstract

The present invention discloses a two-speed transmission system for a hub motor with an integrated multiplexed electronic mechanical brake. The system mainly comprises a drive motor, a central support shaft, a speed-changing planetary gear train, a reduction gear train, a controllable one-way clutch, an electronic mechanical brake, and a hub. The inner and outer rings of the controllable one-way clutch are respectively connected to the central support shaft and the first sun gear; the planetary carrier of the speed-changing planetary gear train is connected to the torque output frame; the sun gear of the speed-changing planetary gear train is connected to the hub; the torque output frame is spline-connected to the pressure plate; the pressure plate can be axially moved toward the hub under the action of the clamping actuator of the electronic mechanical brake to achieve mutual contact and sliding connection through the friction lining. The two-speed transmission of the hub motor can achieve nine different operating states: first gear drive, second gear drive, neutral, reverse, first gear pure electric braking, second gear pure electric braking, first gear mechanical braking, first gear compound braking, and parking brake by controlling the electronic mechanical brake and the controllable one-way clutch.

Description

Technical Field

[0001] The present invention belongs to the field of electric vehicle transmission, and in particular relates to a highly integrated hub motor two-speed transmission system with integrated multiplexed electronic mechanical brakes. Background Art

[0002] In recent years, with the development of electrification in the automotive industry, electric vehicles, with their advantages of low emissions, low energy consumption, and high performance, have gradually become one of the future development directions of automobiles. Currently, electric vehicle drive systems are mainly equipped with single-speed ratio reducers, which have the advantages of simple structure and low cost. However, single-speed ratio reducers also limit the frequency of use of the motor's high efficiency range. In addition, to meet the high performance requirements of electric vehicles, they often need to be matched with drive motors with higher peak torque, which will make the motors too heavy and large. To solve these problems, some scholars and companies have proposed two-speed transmissions for electric vehicles, which can effectively improve the power and economy of electric vehicles and reduce the size and weight of the motors.

[0003] On the other hand, the automotive distributed drive system represented by the hub motor drive system can effectively improve the vehicle's handling, stability and economy through torque optimization distribution, and has attracted the attention of many scholars and companies.

[0004] At the same time, electronic mechanical brakes can effectively improve the response speed and control accuracy of vehicle braking, and improve the vehicle braking energy recovery rate. Therefore, they have received great attention from relevant companies and scholars in recent years.

[0005] To effectively combine the advantages of a two-speed transmission and an in-wheel motor, and to effectively integrate the in-wheel motor, two-speed transmission, and electro-mechanical brake to achieve the goal of multiplexing actuators, this invention proposes a novel in-wheel motor two-speed transmission system with integrated multiplexing electro-mechanical brakes. The system primarily comprises a drive motor, a reduction gear train, a speed-changing planetary gear train, a controllable one-way clutch, and an electro-mechanical brake. It can achieve nine different operating states: first gear drive, second gear drive, neutral, reverse, first gear pure electric braking, second gear pure electric braking, first gear mechanical braking, first gear compound braking, and parking brake. Summary of the Invention

[0006] The present invention provides an in-wheel motor two-speed transmission system with integrated multiplexed electro-mechanical brakes. It can achieve nine different operating states: first-gear drive, second-gear drive, neutral, reverse, first-gear electric braking, second-gear electric braking, first-gear mechanical braking, first-gear combined braking, and parking brake. The in-wheel motor two-speed transmission effectively combines the advantages of a two-speed transmission and an in-wheel motor, integrating it with the electro-mechanical brake to achieve actuator multiplexing without requiring an additional shift friction clutch, reducing system assembly complexity and cost, and improving vehicle power, economy, maneuverability, and stability.

[0007] In order to achieve the above purpose, the following technical solutions are adopted:

[0008] A two-speed transmission system for a hub motor with an integrated multiplexed electronic mechanical brake consists of a drive motor, a central support shaft, a speed-changing planetary gear train, a reduction gear train, a controllable one-way clutch, an electronic mechanical brake, a wheel hub, a transmission housing, etc.

[0009] The drive motor is installed inside the wheel or on the wheel side and is used to output drive torque or electric braking torque.

[0010] The drive motor can be arranged coaxially with the central support shaft, and includes: a motor stator, a motor rotor, a motor output shaft, and a motor housing; the motor stator is fixedly supported on the motor housing; the motor rotor and the motor output shaft are made into one piece; the motor rotor is designed to be a concave structure, which is used to axially make room for the internal space so that the reduction gear system, the controllable one-way clutch and the speed-changing planetary gear system contained in the transmission housing and the motor housing can be compactly arranged in the wheel to save axial space, and the motor output shaft is rotatably supported on the central support shaft and the transmission housing.

[0011] As another technical solution, the drive motor can also be arranged parallel to the central support shaft, and it includes: a motor stator, a motor rotor, a motor output shaft, and a motor housing; the motor stator is fixedly supported on the motor housing; the motor rotor is fixedly connected to the motor output shaft; the motor output shaft is arranged parallel to the central support shaft and is rotatably supported on the motor housing; the motor housing is fixedly connected to the transmission housing with axial bolts; the transmission housing is connected to the vehicle body through a suspension guide rod system.

[0012] The central support shaft is a hollow shaft, which can rotatably support the wheel hub and the drive motor through bearings; the inner end of the central support shaft is used to connect with suspension steering and other mechanisms; the outer end is processed with an external thread and is connected to the central large nut for axially fixing the bearings and wheel hub.

[0013] The speed-changing planetary gear system adopts a double-connected planetary gear system, which includes a first sun gear, a second sun gear, a first planet gear, a second planet gear, a first planet carrier, and a torque output carrier; the first sun gear is rotatably supported on the central support shaft and is fixedly connected to the outer ring of the controllable one-way clutch through a spline; the first sun gear and the first planet gear are externally meshed for transmission, and the second sun gear and the second planet gear are externally meshed for transmission; the first planet gear and the second planet gear are made into one piece and rotatably supported on the first planet carrier, and the first planet carrier is fixedly connected to the torque output carrier; the second sun gear is fixedly connected to the wheel hub through a spline; the torque output carrier is rotatably supported on the transmission housing through a bearing.

[0014] The reduction gear train can be arranged coaxially. In this case, the reduction gear train adopts a double-linked planetary gear revolving gear train to achieve a large speed ratio reduction and torque-increasing transmission in a limited radial space within the wheel; the reduction gear train includes a third sun gear, a third planetary gear, a fourth planetary gear, a third ring gear, and a third planetary carrier; the third sun gear is fixedly connected to the output shaft of the motor, the third planetary gear and the third sun gear are externally meshed for transmission, the fourth planetary gear and the third ring gear are internally meshed for transmission, the third ring gear is fixedly connected to the motor housing by a spline, the third planetary gear and the fourth planetary gear are made into one piece and are rotatably supported on the third planetary carrier, and the third planetary carrier is fixedly connected to the first planetary carrier and is rotatably supported on the motor housing.

[0015] As another technical solution, the reduction gear train can adopt a parallel axis arrangement. In this case, the reduction gear train adopts a two-stage external cylindrical gear train to achieve a large speed ratio reduction and torque-increasing transmission without excessively increasing the axis spacing; the reduction gear train includes a first reduction driving gear, a first reduction driven gear, a second reduction driving gear, a second reduction driven gear, and an intermediate shaft; the first reduction driving gear is fixedly connected to the motor output shaft; the first reduction driven gear and the second reduction driving gear are fixedly supported on the intermediate shaft; the intermediate shaft is coaxially arranged with the central support shaft and rotatably supported on the transmission housing; the second reduction driven gear is fixedly connected with the first planetary carrier and coaxially arranged with the central support shaft; the first reduction driving gear and the first reduction driven gear are externally meshingly transmitted, and the second reduction driving gear and the second reduction driven gear are externally meshingly transmitted.

[0016] A transmission housing, for partially or completely accommodating the reduction gear train and the speed-changing planetary gear train when the drive motor is arranged inside the wheel or arranged on the wheel edge;

[0017] The controllable one-way clutch can be controlled to achieve a one-way locking state, and can be controlled to switch from the one-way locking state to a two-way locking state or a two-way overrunning state. It includes the inner ring, the outer ring, multiple first pawls, multiple second pawls, multiple return springs, a control disk, and an outer rotor motor.

[0018] In which, there is a certain gap between the inner ring and the outer ring; the inner surface of the inner ring is fixedly connected to the central support shaft by a spline, and the outer surface is processed with a bidirectional ratchet protrusion; the outer surface of the outer ring is processed with a spline and fixedly connected to the first sun gear, and the inner surface is installed with a plurality of first pawls and second pawls arranged evenly and staggered, and the first pawl and the second pawl are installed in opposite directions, and the movable ends of the first pawl and the second pawl are respectively fixedly installed with a control pin; the return spring is installed between the movable end of the first pawl and the outer ring and the movable end of the second pawl and the outer ring; the control pin cooperates with the control disk and can move radially within the space limited by the control disk under the drive of the outer rotor motor; the movable end of the first pawl and the movable end of the second pawl can contact the bidirectional ratchet protrusion on the outer surface of the inner ring under the action of the return spring, thereby locking the inner ring in counterclockwise and clockwise rotation respectively.

[0019] The control disk is mounted on the side surfaces of the inner ring and the outer ring; the control disk is machined with multiple sets of control grooves of two different shapes arranged alternately around the circumference, which respectively cooperate with the control pins of the first pawl and the control pins of the second pawl to constrain the spatial range in which the respective control pins can move. The total number of the control pins is the same as the total number of the control grooves; the constraint relationship is specifically expressed as follows:

[0020] When the control disk is in the middle position, the first pawl control pin is not controlled by the corresponding control groove, and the first pawl movable end is pushed toward the bidirectional ratchet protrusion on the outer surface of the inner ring under the action of the return spring, while the second pawl control pin is controlled by the corresponding control groove, and the second pawl movable end is pushed outward under the action of the control groove and does not contact the bidirectional ratchet protrusion on the outer surface of the inner ring. At this time, the controllable one-way clutch is in a one-way locked state in which the inner ring is locked in counterclockwise rotation.

[0021] When the control disk rotates counterclockwise from the middle position by a certain angle, the first pawl control pin and the second pawl control pin are no longer controlled by their corresponding control grooves, and the first pawl movable end and the second pawl movable end are pushed toward the two-way ratchet protrusion on the outer surface of the inner ring under the action of the return spring. At this time, the controllable one-way clutch is in a two-way locked state.

[0022] When the control disk rotates clockwise from the middle position by a certain angle, the first pawl control pin and the second pawl control pin are both controlled by the corresponding control grooves, and the first pawl movable end and the second pawl movable end are both pushed outward under the action of the control grooves and do not contact the bidirectional ratchet protrusion on the outer surface of the inner ring. At this time, the inner ring and the outer ring are completely separated, and the controllable one-way clutch is in a bidirectional overrunning state.

[0023] The outer rotor motor includes: an outer rotor of the motor, an inner stator of the motor, and an outer rotor motor housing; the outer rotor motor housing is fixedly connected to the central support shaft by a spline; the inner stator of the motor is fixed to the outer rotor motor housing; the outer rotor of the motor is rotatably supported on the central support shaft and fixedly connected to the control disk; the central support shaft is a hollow shaft and is machined with a radial hole at the fixing position of the outer rotor motor housing; the outer rotor motor power harness can be connected to the outer rotor motor through the hollow hole inside the central support shaft and the radial hole.

[0024] The electronic mechanical brake serves as both a shift actuator and a driving brake actuator, and includes a clamping actuator, a pressure plate, a friction lining 1, and a friction lining 2. The pressure plate is coaxially arranged with the central support shaft, a portion of which is located inside the transmission housing and is slidingly connected to the torque output frame via a spline, and the other portion is located outside the transmission housing and is installed with the friction lining 1; the friction lining 2 is installed on the wheel hub, and the positions of the friction lining 1 and the friction lining 2 correspond to each other; the pressure plate can move axially along the central support shaft under the action of the clamping actuator and cause the friction lining 1 and the friction lining 2 to be pressed, contacted, and rubbed against each other or clamped and locked.

[0025] The clamping actuator includes a screw, a steel ball, a nut, a worm, a worm gear, and an actuator motor; the screw is a hollow shaft, coaxially arranged with the central support shaft, and rotatably supported on the pressure plate by a bearing, and the screw can apply axial clamping force to the pressure plate through the bearing; a steel ball raceway is processed on the outer surface of the screw, and a steel ball raceway is processed on the inner surface of the nut, the nut is installed on the outside of the screw, and the steel ball is installed between the nut and the screw; when the nut rotates around the central support shaft, it can push the screw to produce axial displacement; the worm gear is fixedly connected to the nut and rotatably supported on the transmission housing by a bearing; the worm is meshed with the worm gear for transmission and is fixedly connected to the actuator motor; the torque output by the actuator motor can push the pressure plate to move axially after passing through the worm, the worm gear, the nut, and the screw, so that the friction lining 1 on the pressure plate and the friction lining 2 on the wheel hub are pressed against each other; the worm and the worm gear can achieve reverse transmission self-locking.

[0026] When the two-speed transmission of the wheel hub motor is in the first gear driving state, the electronic mechanical brake is controlled to be in the disengaged state, the controllable one-way clutch is controlled to be in the bidirectional locked state, and the drive motor rotates in the positive direction to output the driving torque, thereby meeting the low-speed acceleration power requirements of the vehicle;

[0027] When the two-speed transmission of the wheel hub motor is in the second-gear driving state, the electronic mechanical brake is controlled to be in a fully clamped state, the controllable one-way clutch is controlled to be in a two-way overrunning state, and the drive motor rotates in the positive direction to output driving torque, meeting the economic requirements of high-speed cruising of the car;

[0028] When the two-speed transmission of the wheel hub motor is in neutral, the electronic mechanical brake is controlled to be in a disengaged state, the controllable one-way clutch is controlled to be in a two-way overrunning state, and the drive motor does not output torque, meeting the driving condition requirements when the vehicle is coasting or the drive axle serves as a driven axle;

[0029] When the two-speed transmission of the wheel hub motor is in the reverse state, the electronic mechanical brake is controlled to be in the disengaged state, the controllable one-way clutch is controlled to be in the bidirectional locked state, and the drive motor rotates in the reverse direction to output the driving torque, thereby meeting the requirements of the vehicle's reverse driving condition;

[0030] When the two-speed transmission of the wheel hub motor is in the first gear pure electric braking state, the electronic mechanical brake is controlled to be in the disengaged state, the controllable one-way clutch is controlled to be in the bidirectional locked state, and the drive motor rotates in the positive direction to output electromagnetic braking torque, meeting the requirements of the low and medium speed high braking deceleration working conditions of the vehicle;

[0031] When the two-speed transmission of the wheel hub motor is in the second-speed pure electric braking state, the electronic mechanical brake is controlled to be in a fully clamped state, the controllable one-way clutch is controlled to be in a two-way overrunning state, and the drive motor rotates in the positive direction to output electromagnetic braking torque, meeting the high-speed and small braking deceleration working conditions of the vehicle;

[0032] When the two-speed transmission of the wheel hub motor is in the first gear mechanical braking state, the electronic mechanical brake is controlled to be in a semi-clamped sliding friction state, the controllable one-way clutch is controlled to be in a two-way locked state, and the drive motor does not output torque. At this time, the friction braking force generated by the electronic mechanical brake decelerates the vehicle, meeting the working condition requirement that the drive motor is not efficient enough during the braking and deceleration process of the vehicle and needs to be replaced by mechanical friction braking deceleration;

[0033] When the two-speed transmission of the wheel hub motor is in the first-speed compound braking state, the electronic mechanical brake is controlled to be in a semi-clamped sliding state, the controllable one-way clutch is controlled to be in a bidirectional locked state, and the drive motor rotates in the positive direction to output electromagnetic braking torque. At this time, the vehicle decelerates under the combined action of the regenerative braking of the drive motor and the friction braking force generated by the electronic mechanical brake, meeting the working condition requirements of the vehicle braking deceleration process where the regenerative braking current is limited by the battery or the regenerative braking force capacity of the motor is insufficient;

[0034] When the two-speed transmission of the hub motor is in the parking brake state, the electronic mechanical brake is controlled to be in a fully clamped and locked state, the controllable one-way clutch is controlled to be in a two-way locked state, and the drive motor does not output torque. At this time, the internal transmission of the two-speed transmission of the hub motor is self-locking, meeting the working condition requirements of the vehicle to be stable on a slope.

[0035] The beneficial effects of the present invention are:

[0036] 1. The in-wheel motor two-speed transmission system with integrated multiplexed electronic mechanical brakes described in the present invention can effectively combine the advantages of an electric vehicle's two-speed transmission and an in-wheel motor distributed drive system, effectively improving the vehicle's economy, power, maneuverability, and stability, and conforming to the development trend of chassis integration.

[0037] 2. The two-speed transmission system of a hub motor with an integrated multiplexed electronic mechanical brake described in the present invention can achieve shift control by multiplexing the electronic mechanical brake, that is, the motor mechanical brake can act as both a brake actuator and a shift actuator, thereby reducing one execution controller and lowering production costs.

[0038] 3. The two-speed transmission system of a hub motor with an integrated multiplexed electronic mechanical brake described in the present invention can achieve nine different working states, namely, first gear drive, second gear drive, neutral, reverse, first gear pure electric braking, second gear pure electric braking, first gear mechanical braking, first gear compound braking, and parking brake, simply by controlling the working states of the controllable one-way clutch, the electronic mechanical brake, and the motor. The innovative structure not only realizes the shifting between the first gear and the second gear without power interruption during the driving and braking process, but also significantly reduces the difficulty of switching control between different working states.

[0039] 4. The two-speed transmission system of a hub motor with an integrated multiplexed electronic mechanical brake described in the present invention uses two sets of compound planetary gear systems, and the system integration is highly compact. At the same time, by multiplexing the shift actuator and the brake actuator, the number of corresponding components of the system can be effectively reduced, which facilitates further integration and layout of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1This is a simplified structural diagram of a two-speed transmission system for a hub motor with an integrated multiplexed electronic mechanical brake according to the present invention.

[0041] Figure 2 This is a structural diagram of a two-speed transmission system for a hub motor with an integrated multiplexed electronic mechanical brake according to the present invention.

[0042] Figure 3 This is a simplified structural diagram of the second solution of the two-speed transmission system of a hub motor with integrated multiplexed electronic mechanical brake according to the present invention.

[0043] Figure 4 This is a partial structural diagram of a controllable one-way clutch of a two-speed transmission system of a hub motor with an integrated multiplexed electronic mechanical brake as described in the present invention.

[0044] Figure 5 This is a structural diagram of a controllable one-way clutch control disk of a two-speed transmission system of a hub motor with an integrated multiplexed electronic mechanical brake as described in the present invention.

[0045] Figure 6 Schematic diagram of the one-way locking state of the controllable one-way clutch of the two-speed transmission system of the hub motor with integrated multiplexed electronic mechanical brake according to the present invention

[0046] Figure 7 Schematic diagram of the controllable one-way clutch bidirectional locking state principle of the hub motor two-speed transmission system with integrated multiplexed electronic mechanical brake according to the present invention

[0047] Figure 8 Schematic diagram of the controllable one-way clutch bidirectional overrunning state principle of the hub motor two-speed transmission system with integrated multiplexed electronic mechanical brake according to the present invention DETAILED DESCRIPTION

[0048] The present invention is further described in detail below with reference to the accompanying drawings so that those skilled in the art can implement the invention with reference to the description. An embodiment of the in-wheel motor two-speed transmission system with integrated multiplexed electronic mechanical brake according to the present invention is as follows:

[0049] like Figure 1 、 Figure 2 As shown, a two-speed transmission system of a hub motor with an integrated multiplexed electronic mechanical brake includes a drive motor 100, a central support shaft 201, a speed-changing planetary gear train 400, a reduction gear train 300, a controllable one-way clutch 500, an electronic mechanical brake 600, a hub 700, a transmission housing 608, etc.

[0050] The drive motor 100 is installed inside the wheel or on the wheel side, and is used to output drive torque or electric braking torque.

[0051] The drive motor 100 can be arranged coaxially with the central support shaft 201, and includes: a motor stator 101, a motor rotor 102, a motor output shaft 103, and a motor housing 104; the motor stator 101 is fixedly supported on the motor housing 104; the motor rotor 102 is fixedly connected to the motor output shaft 103; the motor output shaft 103 is arranged coaxially with the central support shaft 201, and is rotatably supported on the central support shaft 201 and the motor housing 104.

[0052] like Figure 3 As shown, as another technical solution, the drive motor 100 can also be arranged parallel to the central support shaft 201; the motor stator 101 is fixedly supported on the motor housing 104; the motor rotor 102 is fixedly connected to the motor output shaft 103; the motor output shaft 103 is arranged parallel to the central support shaft 201 and is rotatably supported on the motor housing 104.

[0053] The central support shaft 201 is a hollow shaft, which can rotatably support the wheel hub 700 through bearings 203 and 204; the inner end of the central support shaft 201 is used to connect with suspension steering and other mechanisms; the outer end is processed with an external thread and is connected to the central large nut 202, which is used to axially fix the bearing 204 and the wheel hub 700.

[0054] The speed-changing planetary gear system 400 includes a first sun gear 401, a second sun gear 404, a first planet gear 402, a second planet gear 403, a first planet carrier 405, and a torque output carrier 406; the first sun gear 401 is rotatably supported on the central support shaft 201 through a bearing wheel and is fixedly connected to the outer ring 502 of the controllable one-way clutch through a spline; the first sun gear 401 and the first planet gear 402 are externally meshed for transmission, and the second sun gear 404 and the second planet gear 403 are externally meshed for transmission; the first planet gear 402 and the second planet gear 403 are made into one piece and rotatably supported on the first planet carrier 405, and the first planet carrier 405 is fixedly connected to the torque output carrier 406; the second sun gear 404 is fixedly connected to the wheel hub 700 through a spline; the torque output carrier 406 is rotatably supported on the transmission housing 608 through a bearing.

[0055] The reduction gear train 300 can adopt a revolving gear train, which includes a third sun gear 301, a third planetary gear 302, a fourth planetary gear 303, a third ring gear 304, and a third planetary carrier 305; the third sun gear 301 is fixedly connected to the motor output shaft 103, the third planetary gear 302 is externally meshed with the third sun gear 301 for transmission, the fourth planetary gear 303 is internally meshed with the third ring gear 304 for transmission, the third ring gear 304 is fixedly connected to the motor housing 104 through a spline, the third planetary gear 302 and the fourth planetary gear 303 are made into one piece and are rotatably supported on the third planetary carrier 305, and the third planetary carrier 305 is fixedly connected to the first planetary carrier 405 and is rotatably supported on the motor housing 104.

[0056] like Figure 3 As shown, as another technical solution, the reduction gear train 300 can adopt a parallel axis arrangement, which includes a first reduction driving gear 306, a first reduction driven gear 307, a second reduction driving gear 308, a second reduction driven gear 309, and an intermediate shaft 310; the first reduction driving gear 306 is fixedly connected to the motor output shaft 103; the first reduction driven gear 307 and the second reduction driving gear 308 are fixedly supported on the intermediate shaft 310; the intermediate shaft 310 is coaxially arranged with the central support shaft 201 and rotatably supported on the transmission housing; the second reduction driven gear 309 is fixedly connected with the first planetary carrier 405 and coaxially arranged with the central support shaft 201; the first reduction driving gear 306 and the first reduction driven gear 307 are externally meshed for transmission, and the second reduction driving gear 308 and the second reduction driven gear 309 are externally meshed for transmission.

[0057] like Figure 4 、 Figure 5 As shown, the controllable one-way clutch 500 can be controlled to achieve a one-way locking state, and can be controlled to switch from the one-way locking state to a two-way locking state or a two-way overrunning state, which includes the inner ring 501, the outer ring 502, multiple first pawls 503, multiple second pawls 504, multiple return springs 505, a control disk 506, and an outer rotor motor.

[0058] There is a certain gap between the inner ring 501 and the outer ring 502; the inner surface of the inner ring 501 is fixedly connected to the central support shaft 201 through a spline, and the outer surface is processed with a bidirectional ratchet protrusion; the outer surface of the outer ring 502 is processed with a spline and fixedly connected to the first sun gear 401, and the inner surface is installed with a plurality of evenly staggered first pawls 503 and a plurality of second pawls 504, the first pawls 503 and the second pawls 504 are installed in opposite directions, and the movable ends of the first pawl 503 and the second pawl 504 are respectively fixedly installed with control pins 503 (a) and 504 (b ); the reset spring 505 is installed between the movable end of the first pawl 503 and the outer ring 502, and between the movable end of the second pawl 504 and the outer ring 502; the control pins 503 (a) and 504 (b) cooperate with the control disk 506, and can move radially within the space defined by the control disk 506 under the drive of the outer rotor motor; the movable end of the first pawl 503 and the movable end of the second pawl 504 can contact the bidirectional ratchet protrusion on the outer surface of the inner ring 501 under the action of the reset spring 505, thereby locking the inner ring 501 in counterclockwise and clockwise rotation respectively.

[0059] The control disk 506 is mounted on the side surfaces of the inner ring 501 and the outer ring 502. The control disk 506 is machined with multiple sets of control grooves of two different shapes arranged alternately around the circumference, which respectively cooperate with the control pin 503(a) of the first pawl 503 and the control pin 504(a) of the second pawl 504 to constrain the spatial range within which the respective control pins can move. The total number of the control pins is the same as the total number of the control grooves. The constraint relationship is specifically expressed as follows:

[0060] like Figure 6 As shown, when the control disk 506 is in the middle position, the first pawl control pin 503 is not controlled by the corresponding control groove, and the movable end of the first pawl 503 is pushed toward the bidirectional ratchet protrusion on the outer surface of the inner ring 501 under the action of the reset spring 505, while at this time the second pawl 504 control pin 504 (a) is controlled by the corresponding control groove, and the movable end of the second pawl 504 is pushed outward under the action of the control groove and does not contact the bidirectional ratchet protrusion on the outer surface of the inner ring 501. At this time, the controllable one-way clutch 500 is in a one-way locked state in which the inner ring 501 is locked in counterclockwise rotation.

[0061] like Figure 7As shown, when the control disk 506 rotates counterclockwise from the middle position by a certain angle, the first pawl 503 control pin 503 (a) and the second pawl 504 control pin 504 (a) are not controlled by their respective corresponding control grooves, and the movable ends of the first pawl 503 and the second pawl 504 are pushed toward the two-way ratchet protrusion on the outer surface of the inner ring 501 under the action of the reset spring 505. At this time, the controllable one-way clutch 500 is in a two-way locked state.

[0062] like Figure 8 As shown, when the control disk 506 rotates clockwise from the middle position by a certain angle, the first pawl 503 control pin 503 (a) and the second pawl 504 control pin 504 (a) are both controlled by their corresponding control grooves, and the movable ends of the first pawl 503 and the second pawl 504 are both pushed outward under the action of the control grooves, and do not contact the two-way ratchet protrusions on the outer surface of the inner ring 501. At this time, the inner ring 501 and the outer ring 502 are completely separated, and the controllable one-way clutch 500 is in a two-way overrunning state.

[0063] The outer rotor motor includes: an outer rotor 507, an inner stator 508, and an outer rotor motor housing 509; the outer rotor motor housing 509 is fixedly connected to the central support shaft 201 via a spline; the inner stator 508 is fixed to the outer rotor motor housing 509; the outer rotor 507 is rotatably supported on the central support shaft 201 and is fixedly connected to the control disk 506; the central support shaft 201 is a hollow shaft, and a radial hole is machined at the fixing position of the outer rotor motor housing 509; the outer rotor motor power harness can be connected to the outer rotor motor through the hollow hole inside the central support shaft 201 and the radial hole.

[0064] The electronic mechanical brake 600 can act as a shift actuator and a brake actuator, including a clamping actuator, a pressure plate 601, a friction lining 1 610, and a friction lining 2 611. The pressure plate 601 is coaxially arranged with the central support shaft 201, a part of which is located inside the transmission housing and is connected to the torque output frame 406 through a spline sliding connection, and the other part is located outside the transmission housing and is installed with the friction lining 1 610; the friction lining 2 611 is installed on the wheel hub 700, and the positions of the friction lining 1 610 and the friction lining 2 611 correspond to each other; the pressure plate 601 can move axially along the central support shaft 201 under the action of the clamping actuator and make the friction lining 1 610 and the friction lining 2 611 contact and press each other; during the axial movement of the pressure plate 601, it is always connected to the torque output frame 406 through a spline sliding connection.

[0065] The clamping actuator includes a bearing 602, a screw 603, a steel ball 604, a nut 605, a worm gear 606, a worm 607, and an actuator motor 609; the screw 603 is a hollow shaft, coaxially arranged with the central support shaft 201, and rotatably supported on the pressure plate 601 through the bearing 602, and the screw 603 can apply axial clamping force to the pressure plate 601 through the bearing 602; the outer surface of the screw 603 is processed with a steel ball raceway, and the inner surface of the nut 605 is processed with a steel ball raceway, the nut 605 is installed outside the screw 603, and the steel ball 604 is installed between the nut 605 and the screw 603; when the nut 605 rotates around the central support shaft 201, it can push the screw 603 Generate axial displacement; the worm wheel 606 is fixedly connected to the nut 605 and is rotatably supported on the transmission housing 608 through a bearing; the worm 607 is meshed with the worm wheel 606 for transmission and is fixedly connected to the actuator motor 609; the torque output by the actuator motor 609 passes through the worm 607, the worm wheel 606, the nut 605, the steel ball 604, the screw 603 and the bearing 602, and can push the pressure plate 601 to move axially, so that the friction lining 1 610 on the pressure plate 601 and the friction lining 2 611 on the hub 700 are pressed against each other; the worm 607 and the worm wheel 606 can realize reverse transmission self-locking, and a dust cover 612 is installed on the outside of the clamping actuator.

[0066] When the wheel hub motor two-speed transmission is in the first gear driving state, the electronic mechanical brake 600 is in the disengaged state, the controllable one-way clutch 500 is in the bidirectional locked state, and the drive motor 100 rotates in the positive direction to output the driving torque; when the wheel hub motor two-speed transmission is in the second gear driving state, the electronic mechanical brake 600 is in the fully clamped state, the controllable one-way clutch 500 is in the bidirectional overrunning state, and the drive motor 100 rotates in the positive direction to output the driving torque; when the wheel hub motor two-speed transmission is in the neutral state, When the wheel hub motor two-speed transmission is in the reverse state, the electronic mechanical brake 600 is in the disengaged state, the controllable one-way clutch 500 is in the two-way overrunning state, and the drive motor 100 does not output torque; when the wheel hub motor two-speed transmission is in the reverse state, the electronic mechanical brake 600 is in the disengaged state, the controllable one-way clutch 500 is in the two-way locked state, and the drive motor 100 rotates in the reverse direction to output driving torque; when the wheel hub motor two-speed transmission is in the first gear pure electric braking state, the electronic mechanical brake 600 is in the disengaged state, the controllable one-way clutch 500 is in the two-way locked state, and the drive motor 100 rotates in the reverse direction to output driving torque. The one-way clutch 500 is in a bidirectional locking state, and the drive motor 100 rotates in the positive direction to output braking torque; when the two-speed transmission of the hub motor is in the second-gear pure electric braking state, the electronic mechanical brake 600 is in a fully clamped state, the controllable one-way clutch 500 is in a bidirectional overrunning state, and the drive motor 100 rotates in the positive direction to output braking torque; when the two-speed transmission of the hub motor is in the first-gear mechanical braking state, the electronic mechanical brake 600 is in a sliding clamping state, and the controllable one-way clutch 500 is in a bidirectional overrunning state. In the locked state, the drive motor 100 does not output torque; when the two-speed transmission of the hub motor is in the first gear compound braking state, the electronic mechanical brake 600 is in the slip clamping state, the controllable one-way clutch 500 is in the bidirectional locked state, and the drive motor 100 rotates in the positive direction to output braking torque; when the two-speed transmission of the hub motor is in the parking brake state, the electronic mechanical brake 600 is in the fully clamped state, the controllable one-way clutch 500 is in the bidirectional locked state, and the drive motor 100 does not output torque.

[0067] The one-way locked state of the controllable one-way clutch 500 is a transition state when the hub motor two-speed transmission switches between the first gear driving state and the second gear driving state.

[0068] Although the embodiments of the present invention have been disclosed above, they are not limited to the applications listed in the description and implementation methods. They can be fully applied to various fields suitable for the present invention. For those familiar with the art, additional modifications can be easily implemented. Therefore, without departing from the general concept defined by the claims and the scope of equivalents, the present invention is not limited to the specific details and illustrations shown and described herein.

Claims

1. A two-speed transmission system for a hub motor with an integrated multiplexed electronic mechanical brake, characterized in that: include: The drive motor is installed inside the wheel or on the wheel side to output drive torque or electric braking torque; The central support shaft is a hollow shaft used to rotatably support the wheel hub and the drive motor; A reduction gear train, used for reducing the speed of the torque output by the drive motor and increasing the torque before outputting it; a controllable one-way clutch supported on the central support shaft; A variable-speed planetary gear train adopts a double-linked planetary gear train, which includes a first sun gear, a second sun gear, a first planet gear, a second planet gear, a first planet carrier, and a torque output carrier. The first sun gear is supported and connected to the central support shaft through the controllable one-way clutch. The first sun gear and the first planet gear are externally meshed for transmission. The second sun gear and the second planet gear are externally meshed for transmission. The first planet gear and the second planet gear are integrally formed and rotatably supported on the first planet carrier. The first planet carrier is fixedly connected to the torque output carrier, and the second sun gear is fixedly connected to the wheel hub spline. A transmission housing, for partially or completely accommodating the reduction gear train and the speed-changing planetary gear train when the drive motor is arranged inside the wheel or arranged on the wheel edge; an electromechanical brake serving as both a shift actuator and a driving brake actuator, comprising a clamping actuator, a pressure plate, a first friction lining, and a second friction lining; a portion of the pressure plate being located inside the transmission housing and slidingly connected to the torque output frame via a spline; another portion of the pressure plate being located outside the transmission housing and mounted with the first friction lining; the second friction lining being mounted on the wheel hub and facing the first friction lining; the pressure plate being axially movable along the central support shaft under the action of the clamping actuator to cause the first friction lining and the second friction lining to be in pressurized contact and sliding friction or to be clamped and locked against each other; The two-speed transmission system of the hub motor with integrated multiplexed electronic mechanical brake can realize nine different working states: first gear drive, second gear drive, neutral, reverse, first gear pure electric braking, second gear pure electric braking, first gear mechanical braking, first gear compound braking, and parking brake.

2. The in-wheel motor two-speed transmission system with integrated multiplexed electronic mechanical brake according to claim 1, characterized in that: The drive motor is coaxially arranged with the central support shaft, and includes: a motor stator, a motor rotor, a motor output shaft, and a motor housing; the motor stator is fixedly supported on the motor housing; the motor rotor and the motor output shaft are made as one piece; the motor rotor is designed to be a concave structure, which is used to axially free up internal space so that the reduction gear system, the controllable one-way clutch and the speed-changing planetary gear system contained in the transmission housing and the motor housing can be compactly arranged in the wheel to save axial space, and the motor output shaft is rotatably supported on the central support shaft and the transmission housing.

3. The two-speed transmission system of a hub motor with integrated multiplexed electronic mechanical brake according to claim 1, characterized in that: The reduction gear train can be arranged coaxially. In this case, the reduction gear train adopts a double-linked planetary gear revolving gear train to achieve a large speed ratio reduction and torque-increasing transmission in a limited radial space within the wheel; the reduction gear train includes a third sun gear, a third planetary gear, a fourth planetary gear, a third ring gear, and a third planetary carrier; the third sun gear is fixedly connected to the output shaft of the motor, the third planetary gear is externally meshed with the third sun gear for transmission, the fourth planetary gear is internally meshed with the third ring gear for transmission, the third ring gear is fixedly connected to the motor housing, the third planetary gear and the fourth planetary gear are made into one piece and are rotatably supported on the third planetary carrier, and the third planetary carrier is fixedly connected to the first planetary carrier and is rotatably supported on the motor housing.

4. The in-wheel motor two-speed transmission system with integrated multiplexed electronic mechanical brake according to claim 1, characterized in that: The controllable one-way clutch comprises an inner ring, an outer ring, a plurality of first pawls, a plurality of second pawls, a plurality of return springs, a control disk, and an outer rotor control motor; wherein, there is a certain gap between the inner ring and the outer ring; the inner surface of the inner ring is fixedly connected to the central support shaft by a spline, and the outer surface of the inner ring is machined with a bidirectional ratchet protrusion; the outer surface of the outer ring is machined with a spline and fixedly connected to the first sun gear spline, and the inner surface of the outer ring is installed with a plurality of first pawls and a plurality of second pawls arranged evenly and staggered, and the first pawl and the second pawl are installed in opposite directions, and the movable ends of the first pawl and the second pawl are respectively fixedly installed with a control pin; the return spring is installed between the movable end of the first pawl and the outer ring and the movable end of the second pawl and the outer ring; the control pin cooperates with the control disk and can move radially within the space defined by the control disk under the drive of the outer rotor control motor; the movable end of the first pawl and the movable end of the second pawl can contact the bidirectional ratchet protrusion on the outer surface of the inner ring under the action of the return spring, thereby locking the counterclockwise rotation and clockwise rotation of the inner ring respectively.

5. The two-speed transmission system of a hub motor with integrated multiplexed electronic mechanical brake as claimed in claim 4, characterized in that: The control disk is mounted on the side surfaces of the inner ring and the outer ring; the control disk is machined with multiple sets of control grooves of two different shapes arranged alternately around the circumference, which respectively cooperate with the control pins of the first pawl and the control pins of the second pawl to constrain the spatial range in which the respective control pins can move. The total number of the control pins is the same as the total number of the control grooves; the constraint relationship is specifically expressed as follows: When the control disk is in the middle position, the first pawl control pin is not controlled by the corresponding control groove, and the movable end of the first pawl is pushed toward the bidirectional ratchet protrusion on the outer surface of the inner ring under the action of the return spring. At this time, the second pawl control pin is controlled by the corresponding control groove, and the movable end of the second pawl is pulled outward under the action of the control groove and does not contact the bidirectional ratchet protrusion on the outer surface of the inner ring. At this time, the controllable one-way clutch is in a one-way locked state in which the inner ring is locked when it rotates counterclockwise and disengaged when it rotates clockwise; When the control disk rotates counterclockwise from the middle position by a certain angle, the first pawl control pin and the second pawl control pin are no longer controlled by their corresponding control grooves, and the first pawl movable end and the second pawl movable end are both pushed toward the bidirectional ratchet protrusion on the outer surface of the inner ring under the action of the return spring. At this time, the controllable one-way clutch is in a bidirectional locked state; When the control disk rotates clockwise from the middle position by a certain angle, the first pawl control pin and the second pawl control pin are both controlled by the corresponding control grooves, and the first pawl movable end and the second pawl movable end are both pulled outward under the action of the control grooves and do not contact the bidirectional ratchet protrusion on the outer surface of the inner ring. At this time, the inner ring and the outer ring are completely separated, and the controllable one-way clutch is in a bidirectional overrunning state.

6. The in-wheel motor two-speed transmission system with integrated multiplexed electronic mechanical brake as claimed in claim 4, characterized in that: The outer rotor control motor includes: an outer rotor of the motor, an inner stator of the motor, and an outer rotor motor housing; the outer rotor motor housing is fixedly connected to the central support shaft by a spline; the inner stator of the motor is fixed in the outer rotor motor housing; the outer rotor of the motor is rotatably supported on the central support shaft and is fixedly connected to the control disk; the central support shaft is machined with a radial hole at the fixing position of the outer rotor motor housing; the power harness of the outer rotor motor can be connected to the outer rotor motor from the vehicle body through the center hole of the central support shaft and the radial hole.

7. The in-wheel motor two-speed transmission system with integrated multiplexed electronic mechanical brake according to claim 1, characterized in that: The clamping actuator includes a screw, a steel ball, a nut, a worm, a worm gear, and an actuator motor; the screw is a hollow shaft, coaxially arranged with the central support shaft, and rotatably supported on the pressure plate by a bearing, and the screw can apply axial clamping force to the pressure plate through the bearing; a steel ball raceway is processed on the outer surface of the screw, and a steel ball raceway is processed on the inner surface of the nut, the nut is mounted on the outside of the screw, and the steel ball is mounted between the nut and the screw, when the nut rotates around the central support shaft, it can push the screw to produce axial displacement; the worm gear is fixedly connected to the nut and rotatably supported on the transmission housing; the worm is meshed with the worm gear for transmission and is fixedly connected to the actuator motor; the torque output by the actuator motor can push the pressure plate to move axially after passing through the worm, the worm gear, the nut, and the screw, so that the friction lining 1 on the pressure plate and the friction lining 2 on the wheel hub are pressed against each other to generate friction; the worm gear and the worm can achieve reverse transmission self-locking.

8. The in-wheel motor two-speed transmission system with integrated multiplexed electronic mechanical brake according to claim 1, characterized in that: When the two-speed transmission of the wheel hub motor is in the first gear driving state, the electronic mechanical brake is controlled to be in the disengaged state, the controllable one-way clutch is controlled to be in the bidirectional locked state, and the drive motor rotates in the positive direction to output the driving torque, thereby meeting the low-speed acceleration power requirements of the vehicle; When the two-speed transmission of the wheel hub motor is in the second-gear driving state, the electronic mechanical brake is controlled to be in a fully clamped state, the controllable one-way clutch is controlled to be in a two-way overrunning state, and the drive motor rotates in the positive direction to output driving torque, meeting the economic requirements of high-speed cruising of the car; When the two-speed transmission of the wheel hub motor is in neutral, the electronic mechanical brake is controlled to be in a disengaged state, the controllable one-way clutch is controlled to be in a two-way overrunning state, and the drive motor does not output torque, meeting the driving condition requirements when the vehicle is coasting or the drive axle serves as a driven axle; When the two-speed transmission of the wheel hub motor is in the reverse state, the electronic mechanical brake is controlled to be in the disengaged state, the controllable one-way clutch is controlled to be in the bidirectional locked state, and the drive motor rotates in the reverse direction to output the driving torque, thereby meeting the requirements of the vehicle's reverse driving condition; When the two-speed transmission of the wheel hub motor is in the first gear pure electric braking state, the electronic mechanical brake is controlled to be in the disengaged state, the controllable one-way clutch is controlled to be in the bidirectional locked state, and the drive motor rotates in the positive direction to output electromagnetic braking torque, meeting the requirements of the low and medium speed high braking deceleration working conditions of the vehicle; When the two-speed transmission of the wheel hub motor is in the second-speed pure electric braking state, the electronic mechanical brake is controlled to be in a fully clamped state, the controllable one-way clutch is controlled to be in a two-way overrunning state, and the drive motor rotates in the positive direction to output electromagnetic braking torque, meeting the high-speed and small braking deceleration working conditions of the vehicle; When the two-speed transmission of the wheel hub motor is in the first gear mechanical braking state, the electronic mechanical brake is controlled to be in a semi-clamped sliding friction state, the controllable one-way clutch is controlled to be in a two-way locked state, and the drive motor does not output torque. At this time, the friction braking force generated by the electronic mechanical brake decelerates the vehicle, meeting the working condition requirement that the drive motor is not efficient enough during the braking and deceleration process of the vehicle and needs to be replaced by mechanical friction braking deceleration; When the two-speed transmission of the wheel hub motor is in the first-speed compound braking state, the electronic mechanical brake is controlled to be in a semi-clamped sliding state, the controllable one-way clutch is controlled to be in a bidirectional locked state, and the drive motor rotates in the positive direction to output electromagnetic braking torque. At this time, the vehicle decelerates under the combined action of the regenerative braking of the drive motor and the friction braking force generated by the electronic mechanical brake, meeting the working condition requirements of the vehicle braking deceleration process where the regenerative braking current is limited by the battery or the regenerative braking force capacity of the motor is insufficient; When the two-speed transmission of the hub motor is in the parking brake state, the electronic mechanical brake is controlled to be in a fully clamped and locked state, the controllable one-way clutch is controlled to be in a two-way locked state, and the drive motor does not output torque. At this time, the internal transmission of the two-speed transmission of the hub motor is self-locking, meeting the working condition requirements of the vehicle to be stable on a slope.

9. The in-wheel motor two-speed transmission system with integrated multiplexed electronic mechanical brake according to claim 1, characterized in that: The drive motor can be arranged parallel to the central support shaft, and includes: a motor stator, a motor rotor, a motor output shaft, and a motor housing; the motor stator is fixedly supported on the motor housing; the motor rotor is fixedly connected to the motor output shaft; the motor output shaft is arranged parallel to the central support shaft and is rotatably supported on the motor housing; the motor housing is fixedly connected to the transmission housing with axial bolts; the transmission housing is connected to the vehicle body through a suspension guide rod system.

10. The two-speed transmission system of a hub motor with integrated multiplexed electronic mechanical brake according to claim 9, characterized in that: The reduction gear train can be arranged in parallel axes. In this case, the reduction gear train adopts a two-stage external cylindrical gear train to achieve a large speed ratio reduction and torque-increasing transmission without excessively increasing the axis spacing; the reduction gear train includes a first reduction driving gear, a first reduction driven gear, a second reduction driving gear, a second reduction driven gear, and an intermediate shaft; The first reduction driving gear is fixedly connected to the motor output shaft; the first reduction driven gear and the second reduction driving gear are fixedly supported on the intermediate shaft; the intermediate shaft is coaxially arranged with the central support shaft; the second reduction driven gear is fixedly connected to the first planetary carrier and coaxially arranged with the central support shaft; the first reduction driving gear and the first reduction driven gear are externally meshed for transmission, and the second reduction driving gear and the second reduction driven gear are externally meshed for transmission.

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