A new type of driving unit based on hub motor

Abstract

The application provides a new type of driving unit based on a wheel hub motor, which comprises a wheel hub, a reduction type wheel hub motor, an electronic mechanical brake system, a circulating ball pull rod electric control steering system, a disconnected double wishbone suspension and a new type of driving unit shell; the upper end of a steering knuckle of the circulating ball pull rod electric control steering system is hinged to an upper wishbone of the suspension, a hinge point serving as a virtual upper positioning point of a kingpin, the lower end of the steering knuckle is hinged to a lower wishbone of the disconnected suspension, and the intersection of the extension lines of the lower wishbone of the disconnected suspension serves as a virtual lower positioning point of the kingpin; the internal size of the virtual kingpin steering release rim is reduced to facilitate the installation of the reduction type wheel hub motor and the electronic mechanical brake system, the kingpin offset distance is reduced to reduce the steering angle envelope and improve the steering lightness; the circulating ball pull rod electric control steering system reduces the axial size to improve the large angle steering of the steering system; the new type of driving unit shell serves as the only connection between the new type of driving unit and the frame, and improves the integrity of the application and the portability among different vehicle models.

Description

Technical Field

[0001] The present invention relates to a wheel module of an electric vehicle, and in particular to a novel driving unit based on a hub motor. Background Art

[0002] The in-wheel motor-based drive unit (DMU) is an ideal configuration for smart cars. It encompasses the drive system, braking system, steering system, and suspension system. It boasts high integration and scalability, allowing for customized body configurations to meet diverse travel and lifestyle needs. DMUs in smart cars leverage their high controllability and maneuverability, enabling various functions such as pivoting and lateral travel, laying the foundation for fully autonomous vehicles.

[0003] However, existing in-wheel motor-based drive units (WMUs) have the hub motor, brake, and steering knuckle mounted side-by-side, making in-wheel space layout difficult. Furthermore, the WMU's large axial dimensions lead to poor heat dissipation and increased tire offset. Furthermore, tie-rod steering, a primary configuration of the WMU's steering system, ensures robust control but consumes significant axial dimension. Furthermore, the numerous connection points between the various WMU systems and the vehicle frame impact vehicle body design and hinder the WMU's portability across different vehicle models.

[0004] Therefore, how to improve the structural compactness, steering flexibility and unit portability of the driving unit has become a technical problem that needs to be solved urgently. Summary of the Invention

[0005] In order to solve the above technical problems, the present invention provides a new type of travel unit based on a hub motor, comprising a wheel hub, a reduction-type hub motor, an electronic mechanical braking system, a recirculating ball tie rod electronically controlled steering system, a disconnected double wishbone suspension and a new type of travel unit housing; a tire is provided on the outside of the rim of the wheel hub; the reduction-type hub motor and the electronic mechanical braking system are arranged inside the rim of the wheel hub; the reduction-type hub motor comprises a hub motor and a planetary reducer, the planetary reducer is embedded in the hub motor, and the input end of the planetary reducer is connected to the rotor through-axis of the hub motor. The fixed end of the deceleration wheel hub motor is fixedly connected to the lower end of the steering knuckle of the recirculating ball pull rod electronically controlled steering system, the rotating end of the deceleration wheel hub motor is fixedly connected to one end of the brake disc of the electronic mechanical braking system, and the other end of the brake disc is fixedly connected to the wheel hub; the electronic mechanical braking system includes a brake disc, a brake motor and a brake caliper, the brake motor and the brake caliper are fixedly connected to the wheel hub motor, the brake motor is in transmission connection with the brake caliper, and the brake caliper is sleeved on the side of the brake disc; the recirculating ball pull rod electronically controlled steering system includes a steering motor, a recirculating ball steering gear, Steering rocker arm, steering straight tie rod and steering knuckle, the steering motor and recirculating ball steering gear are fixedly connected to the inner side of the new travel unit housing, the steering motor, recirculating ball steering gear, steering rocker arm and steering straight tie rod are connected in sequence, and the steering straight tie rod is hinged to one side of the steering knuckle; the disconnected double wishbone suspension includes an upper fork arm of the suspension, a disconnected lower fork arm of the suspension and a spring shock absorber, the upper end of the steering knuckle is hinged to one end of the upper fork arm of the suspension, and the hinge point is located above the wheel hub as the upper positioning point of the virtual steering kingpin, and the lower end of the steering knuckle is hinged to one end of the lower fork arm of the disconnected suspension The intersection of the extension lines of the disconnected suspension lower fork arm is located inside the wheel hub and serves as the lower positioning point of the virtual steering kingpin; the other end of the suspension upper fork arm is hinged to the upper part of the new travel unit shell; the other ends of the disconnected suspension lower fork arms are respectively hinged to the lower part of the new travel unit shell; the upper end of the spring shock absorber is hinged to the upper end of the new travel unit shell, and the lower end of the spring shock absorber is hinged to one of the fork arms of the disconnected suspension lower fork arm; the recirculating ball tie rod electronically controlled steering system and the spring shock absorber are arranged in parallel; the outer side of the new travel unit shell is connected to the vehicle frame.

[0006] Furthermore, the hub motor includes a stator housing, a stator, a rotor support frame and a rotor;

[0007] The stator housing is a hollow cylindrical structure with one end open and a bearing hole in the center of the other end. The stator housing serves as the fixed end of the reduction-type hub motor and is fixedly connected to the lower end of the steering knuckle. The stator, rotor support frame, and rotor are respectively arranged inside the stator housing.

[0008] The stator is arranged on the inner ring of the stator housing, and the stator includes a stator core and a coil winding wound on the stator core;

[0009] The rotor support frame is a hollow cylindrical structure with one end open, and a rotor through-shaft is provided in the center. The rotor support frame is coaxially arranged on the inner ring of the stator, with a gap between the rotor support frame and the stator. One end of the rotor through-shaft extends from the closed end of the rotor support frame and is pivotally connected to the bearing hole of the stator housing. The other end of the rotor through-shaft is coaxially fixed to the sun gear of the planetary reducer.

[0010] The rotor is arranged on the outer ring of the rotor support frame, and a gap is provided between the rotor and the stator; the rotor is a permanent magnet.

[0011] Furthermore, the planetary reducer includes a reducer ring gear, a planetary carrier, planetary wheels and a sun gear; the reducer ring gear is pivotally connected to the open end of the stator housing of the hub motor through a bearing, and the reducer ring gear serves as the rotating end of the reduction-type hub motor, and its outer side is fixedly connected to the brake disc of the electronic mechanical braking system; the planetary carrier is arranged on the inner side of the reducer ring gear, and the planetary wheels are pivotally connected to the planetary carrier and meshed with the reducer ring gear; the sun gear is arranged at the center of the reducer ring gear and meshed with each planetary gear. The sun gear serves as the input end of the planetary reducer and is coaxially fixed to the rotor through-axis.

[0012] Furthermore, the steering knuckle includes an upper transverse arm, a vertical arm, a connecting plate and a lower support arm; the upper transverse arm, the vertical arm, the connecting plate and the lower support arm are connected in sequence to form a Z-type steering knuckle; the upper transverse arm is hinged to one end of the upper fork arm of the suspension through a vertical pin shaft, and the hinge point is located above the tire, serving as a positioning point on the virtual steering kingpin; the lower end of the vertical arm is provided with a connecting plate, which is connected to the fixed end of the reduction type hub motor through the connecting plate; a steering support arm is also provided on one side of the connecting plate, and the steering support arm is hinged to the steering straight pull rod of the recirculating ball tie rod electronic steering system; the lower end of the connecting plate is provided with two lower support arms arranged in parallel in the horizontal direction, and the two lower support arms are respectively hinged to one end of the lower fork arm of the disconnected suspension through a vertical pin shaft.

[0013] Furthermore, the upper fork arm of the suspension is an A-shaped fork arm, the tip of the upper fork arm of the suspension is provided with a vertical axis hole, and the ends of the upper fork arm of the suspension are respectively provided with transverse axis holes; the vertical axis hole of the upper fork arm of the suspension and the upper cross arm of the steering knuckle are hinged through a vertical pin shaft; the transverse axis holes at the ends of the upper fork arm of the suspension are respectively hinged to the inner side wall of the new travel unit shell through transverse pin shafts.

[0014] Furthermore, the disconnected suspension lower wishbone includes two symmetrically arranged single arms, one end of the two single arms are inclined toward each other, the inclined end of the single arm is hinged to one end of the wishbone connecting member through a transverse pin, and the other end of the wishbone connecting member is hinged to the lower support arm at the lower end of the steering knuckle through a vertical pin; the other end of the single arm is hinged to the inner wall of the new travel unit shell through a transverse pin; the intersection of the extension lines of the two single arms is located inside the wheel hub, serving as the lower positioning point of the virtual steering kingpin.

[0015] Furthermore, the new running unit shell includes a suspension upper connecting wall, a suspension lower connecting wall, a frame upper connecting wall, a frame lower connecting wall and a connector; the suspension upper connecting wall and the suspension lower connecting wall are both located on the inside of the connector and are respectively hinged to one end of the suspension upper fork arm and the disconnected suspension lower fork arm; the frame upper connecting wall and the frame lower connecting wall are both located on the outside of the connector and are fixedly connected to the frame; the upper end of the spring shock absorber is hinged to the upper end of the connector; the steering motor and the recirculating ball steering gear of the recirculating ball tie rod electronic steering system are fixedly installed on the inside of the connector; the new running unit shell serves as the only component connecting the new running unit and the frame.

[0016] Working principle of the present invention:

[0017] The present invention provides a novel driving unit based on a hub motor, wherein the reduction-type hub motor and the electronic mechanical braking system are arranged in the rim of the wheel hub, and the steering knuckle, the reduction-type hub motor, the electronic mechanical braking system and the wheel hub are connected in sequence;

[0018] The reduction-type in-wheel motor serves as a drive system, providing driving force for the new travel unit and regenerative braking force through motor reversal;

[0019] The electromechanical braking system provides friction braking force for the new driving unit, and is combined with the deceleration-type wheel hub motor that provides regenerative braking force to form a dual electric braking system;

[0020] The recirculating ball tie rod electronic steering system is connected to the drive system through the steering knuckle and is used to perform large-angle steering with variable transmission ratio on the new travel unit;

[0021] The disconnecting double wishbone suspension is connected to the steering system to form a virtual steering kingpin, and the spring shock absorber of the disconnecting double wishbone suspension is used for buffering and shock absorption of the vehicle body.

[0022] The new running unit housing is connected to the steering system and suspension on the inside and to the vehicle frame on the outside, serving as the only component connecting the new running unit to the vehicle frame.

[0023] The stator shell of the hub motor plays a supporting and fixing role. The stator core and coil winding of the stator provide field strength to drive the rotor permanent magnet to rotate. The rotor drives the rotor support frame to rotate. The rotor support frame drives the sun gear of the planetary reducer to rotate synchronously through the rotor through-shaft; the sun gear of the planetary reducer is decelerated and torque-increased by the planetary gear and the reducer ring gear, and outputs the rotational torque to the brake disc to drive the wheel hub to rotate.

[0024] The planetary reducer of the reduction-type hub motor is completely embedded in the hub motor rotor. The input end of the planetary reducer is connected to the rotor through-shaft of the hub motor. The rotor through-shaft drives the planetary reducer, thereby forming an extreme power density.

[0025] The brake caliper in the electronic mechanical braking system has a fixing frame and brake pads, which are fixed to the deceleration wheel hub motor through the fixing frame. The brake pads are arranged on both sides of the brake disc. The brake motor drives the brake caliper through the deceleration torque increasing device and the motion conversion device to use the brake pads to close to the brake disc to generate friction to form braking force, and the brake disc drives the wheel hub to decelerate.

[0026] The steering motor in the recirculating ball-tie rod electronically controlled steering system rotates the screw of the recirculating ball steering gear, and the screw converts sliding friction into rolling friction through the recirculating ball, driving the nut to move horizontally and the gear fan to rotate. The gear fan of the recirculating ball steering gear pushes the steering straight rod by rotating the steering rocker arm, pulling the steering knuckle to rotate the wheel; compared with other types of steering gears such as rack and pinion type and worm gear type, the recirculating ball steering gear converts the translation of the steering gear output end into rotation, thereby greatly reducing the axial size of the steering system; the recirculating ball-tie rod electronically controlled steering system is arranged in parallel with the spring shock absorber, which reduces the occupied space and improves the flexibility of the new type of unit.

[0027] The upper cross arm, vertical arm, connecting plate and lower support arm of the steering knuckle are connected in sequence to form a Z-shaped steering knuckle; the hinge point of the upper cross arm and the upper fork arm of the suspension is located above the tire, serving as the upper positioning point of the virtual steering kingpin; the lower support arms are respectively rotatably connected to one end of the lower fork arm of the disconnected suspension through a vertical pin shaft.

[0028] The upper fork arm and the lower fork arm of the disconnected double wishbone suspension are respectively connected to the upper transverse arm and the lower support arm of the steering knuckle, forming a virtual steering kingpin upper positioning point and a virtual steering kingpin lower positioning point. The line connecting the virtual steering kingpin upper positioning point and the virtual steering kingpin lower positioning point constitutes a virtual steering kingpin, which provides the steering system with a virtual steering kingpin with zero tire offset, improves steering flexibility, and releases the internal space of the wheel hub for the arrangement of the deceleration hub motor and the electronic mechanical braking system to improve heat dissipation performance; combined with the spring shock absorber, it is used for buffering and shock absorption of the vehicle body.

[0029] The upper fork arm of the suspension is an A-shaped fork arm, the tip of which is hinged to the upper cross arm of the steering knuckle through a vertical pin shaft, and the end of which is hinged to the inner wall of the new travel unit shell instead of being directly connected to the frame.

[0030] The two symmetrically arranged single arms of the disconnected suspension lower fork arm are rotatably connected to the lower support arm at the lower end of the steering knuckle through a fork arm connector; the intersection of the extension lines of the two single arms is located inside the wheel hub, serving as the virtual steering kingpin lower positioning point; the disconnected suspension lower fork arm has a shorter axial dimension than the integral lower fork arm, which frees up space inside the wheel hub while reducing the kingpin offset, thereby improving the steering operation flexibility and structural compactness of the new travel unit.

[0031] The new running unit housing is connected to the vehicle frame. As the only component connecting the new running unit and the frame, it minimizes the structural coupling effects of the new running unit's systems and the frame, thereby improving the portability of the new running unit between different vehicle models and the degree of freedom in vehicle body space design.

[0032] The working process of the present invention:

[0033] During driving, the stator housing is a fixed part, and the rotor permanent magnet is subjected to the magnetic field force formed by the motor winding and the stator core, driving the rotor support frame to rotate synchronously. The rotor is integrated with the planetary reducer through the rotor through-shaft, and the driving torque is transmitted to the wheel hub after being decelerated and amplified by the planetary reducer, providing driving force to drive the new travel unit.

[0034] During braking, the new travel unit's braking force comes from two sources: regenerative braking provided by the in-wheel motor and friction braking provided by the electro-mechanical braking system. Regenerative braking is generated through the reverse process of the in-wheel motor's reverse drive. Furthermore, the electro-mechanical braking system within the wheel hub cavity, through the brake motor, pushes the brake pads of the brake caliper to clamp the brake disc, generating friction braking force. The regenerative braking force generated by the in-wheel motor and the friction braking force generated by the brake disc are transmitted to the tire via the wheel hub. The combined effect of the two generates ground braking force at the tire, which decelerates the new travel unit.

[0035] During steering, the steering motor receives the steering angle signal from the controller and transmits the steering torque to the screw of the recirculating ball steering gear through the output shaft. After the recirculating ball steering gear changes the transmission ratio and direction, the gear fan rotates the steering rocker arm and drives the steering straight tie rod. The steering straight tie rod pushes and pulls the steering knuckle to realize the rotation of the wheel around the virtual steering kingpin with zero kingpin offset inside the wheel.

[0036] When the wheel bounces, the upper fork arm of the suspension, the disconnected lower fork arm of the suspension and the new travel unit housing can rotate freely relative to each other, and perform normal bounce after being buffered and damped by the spring shock absorber.

[0037] Beneficial effects of the present invention:

[0038] 1. This invention achieves virtual kingpin steering through the upper suspension wishbone, disconnectable lower suspension wishbone, and Z-type steering knuckle. This frees up the inner dimensions of the wheel rim to facilitate the installation of a reduction-type in-wheel motor and an electromechanical brake system. It also reduces the kingpin offset to lower the steering wheel angle envelope and improve steering ease.

[0039] 2. The present invention adopts a recirculating ball tie rod electronic steering system, which greatly reduces the axial dimension of the tie rod steering, increases the extreme steering angle range, and realizes high steering flexibility of the new travel unit vehicle;

[0040] 3. The present invention designs a new running unit housing, one side of which is connected to the various systems of the new running unit, enclosing the components of the entire running unit's drive system, braking system, steering system and suspension system; the other side is connected to the vehicle frame, becoming the only component connecting the new running unit to the vehicle frame, thereby improving the integrity of the new running unit and its portability between different vehicles. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0042] Figure 2 This is a schematic diagram of the decomposition structure of the present invention;

[0043] Figure 3 This is a schematic diagram of the structure of the reduction wheel hub motor and the electronic mechanical brake system of the present invention;

[0044] Figure 4 This is a schematic diagram of the inner structure of the wheel hub of the present invention;

[0045] Figure 5 This is a schematic structural diagram of the recirculating ball tie rod electronically controlled steering system of the present invention;

[0046] Figure 6 This is a schematic diagram of the disconnect double wishbone suspension structure of the present invention;

[0047] Figure 7 This is a schematic diagram of the upper wishbone structure of the suspension of the present invention;

[0048] Figure 8 It is a schematic diagram of the partial structure of the steering knuckle and the upper wishbone of the suspension of the present invention;

[0049] Figure 9 This is a schematic diagram of the housing structure of the novel travel unit of the present invention;

[0050] 1. Wheel hub;

[0051] 2. Reduced wheel hub motor 201, wheel hub motor 202, planetary reducer 203, stator housing 204, stator 205, rotor support frame 206, rotor 207, rotor through-shaft 208, reducer ring gear 209, planet carrier 210, planetary gear 211, sun gear;

[0052] 3. Electromechanical brake system 301, brake disc 302, brake motor 303, brake caliper;

[0053] 4. Recirculating ball tie rod electronically controlled steering system 401, steering motor 402, recirculating ball steering gear 403, steering rocker arm 404, steering straight tie rod 405, steering knuckle 406, upper cross arm 407, vertical arm 408, connecting plate 409, lower support arm 410, steering support arm;

[0054] 5. Disconnectable double wishbone suspension 501, suspension upper wishbone 502, disconnectable suspension lower wishbone 503, spring shock absorber 504, vertical shaft hole 505, transverse shaft hole 506, first single arm 507, second single arm 508, wishbone connector;

[0055] 6. New travel unit housing 601, suspension upper connecting wall 602, suspension lower connecting wall 603, frame upper connecting wall 604, frame lower connecting wall 605, and connector. DETAILED DESCRIPTION

[0056] See Figure 1-9 As shown: The present invention provides a new type of travel unit based on a hub motor, comprising a wheel hub 1, a reduction-type hub motor 2, an electronic mechanical braking system 3, a recirculating ball tie rod electronic steering system 4, a disconnecting double wishbone suspension 5 and a new type of travel unit housing 6; a tire is provided on the outside of the rim of the wheel hub 1; the reduction-type hub motor 2 and the electronic mechanical braking system 3 are arranged inside the rim of the wheel hub 1.

[0057] like Figure 3 As shown: the reduction-type hub motor 2 includes a hub motor 201 and a planetary reducer 202; the planetary reducer 202 is completely embedded in the hub motor 201; the hub motor 201 includes a stator housing 203, a stator 204, a rotor support frame 205 and a rotor 206; the stator housing 203 is a hollow cylindrical structure with an open end, and a bearing hole is provided in the center of the other end face; the stator housing 203, as the fixed end of the reduction-type hub motor 2, is fixedly connected to the lower end of the steering knuckle 405 by bolts; the stator 204, the rotor support frame 205 and the rotor 206 are respectively arranged inside the stator housing 203; the stator 204 is arranged in the stator housing 203, the stator 204 includes a stator core and a coil winding wound on the stator core; the rotor support frame 205 is a hollow cylindrical structure with one end open, and a rotor through-shaft 207 is provided in the center; the rotor support frame 205 is coaxially arranged on the inner ring of the stator 204, and a gap is provided between the rotor support frame 205 and the stator 204; one end of the rotor through-shaft 207 extends from the closed end of the rotor support frame 205 and is pivotally connected to the bearing hole of the stator housing 203; the other end of the rotor through-shaft 207 is coaxially fixedly connected to the sun gear 211 of the planetary reducer 202; the rotor 206 is arranged on the outer ring of the rotor support frame 205, and a gap is provided between the rotor 206 and the stator 204; the rotor 206 is a permanent magnet.

[0058] The planetary reducer 202 includes a reducer ring gear 208, a planetary carrier 209, a planetary gear 210 and a sun gear 211; the reducer ring gear 208 is pivotally connected to the open end of the stator housing 203 of the hub motor 201 through a bearing; the reducer ring gear 208 serves as the rotating end of the reduction-type hub motor 2, and its outer side is fixedly connected to the brake disc 301 of the electronic mechanical braking system 3, and the other end of the brake disc 301 is fixedly connected to the hub 1; the planetary carrier 209 is arranged on the inner side of the reducer ring gear 208, and the planetary gear 210 is pivotally connected to the planetary carrier 209 and meshed with the reducer ring gear 208; the sun gear 211 is arranged at the center of the reducer ring gear 208 and meshed with each planetary gear 210; the sun gear 211 serves as the input end of the planetary reducer 202 and is coaxially fixed to the rotor through shaft 207.

[0059] The electronic mechanical braking system 3 includes a brake disc 301, a brake motor 302 and a brake caliper 303; the brake motor 302 and the brake caliper 303 are fixedly connected to the hub motor 201, and the brake motor 302 is connected to the brake caliper 303 through a deceleration and torque increase device and a motion conversion device. The brake caliper 303 is mounted on the side of the brake disc 301.

[0060] like Figure 5 As shown: the recirculating ball tie rod electronic steering system 4 includes a steering motor 401, a recirculating ball steering gear 402, a steering rocker arm 403, a steering straight rod 404 and a steering knuckle 405; the steering motor 401 is fixedly connected to the inner side of the new travel unit housing 6, the output end of the steering motor 401 is connected to the input end screw of the recirculating ball steering gear 402, the output end of the recirculating ball steering gear 402 is connected to the steering rocker arm 403, the steering rocker arm 403 is hinged to the steering straight rod 404, and the steering straight rod 404 is hinged to one side of the steering knuckle 405.

[0061] The steering knuckle 405 includes an upper cross arm 406, a vertical arm 407, a connecting plate 408 and a lower support arm 409; the upper cross arm 406, the vertical arm 407, the connecting plate 408 and the lower support arm 409 are sequentially connected to form a Z-shaped steering knuckle 405; the upper cross arm 406 is hinged to one end of the upper fork arm 501 of the suspension through a vertical pin shaft, and the hinge point is located above the tire, serving as the virtual steering kingpin upper positioning point; the lower end of the vertical arm 407 is provided with a connecting plate 408, which is connected to the upper fork arm 501 through the connecting plate 408. It is connected to the stator housing 203 of the reduction-type hub motor 2 by bolts; a steering arm 410 is also provided on one side of the connecting plate 408 (in this embodiment, it can be the side in the forward direction of the vehicle), and the steering arm 410 is hinged to the steering straight rod 404 of the recirculating ball tie rod electronic steering system 4; the lower end of the connecting plate 408 is provided with two lower arms 409 arranged in parallel in the horizontal direction, and the two lower arms 409 are respectively hinged to one end of the disconnected suspension lower fork arm 502 through a vertical pin shaft.

[0062] like Figure 6 As shown: the disconnected double wishbone suspension 5 includes an upper wishbone 501, a disconnected lower wishbone 502 and a spring shock absorber 503; the upper end of the steering knuckle 405 is hinged to one end of the upper wishbone 501, and the hinge point is located above the wheel hub 1, serving as the virtual steering kingpin upper positioning point; the lower end of the steering knuckle 405 is respectively hinged to one end of the disconnected lower wishbone 502, and the intersection of the extension lines of the disconnected lower wishbone 502 is located inside the wheel hub 1, serving as the virtual steering kingpin upper positioning point. Pin lower positioning point; the other end of the upper fork arm 501 of the suspension is hinged to the upper part of the new travel unit shell 6; the other end of the disconnected suspension lower fork arm 502 is hinged to the lower part of the new travel unit shell 6; the upper end of the spring shock absorber 503 is hinged to the upper end of the new travel unit shell 6, and the lower end of the spring shock absorber 503 is hinged to one of the fork arms of the disconnected suspension lower fork arm 502; the recirculating ball tie rod electronic steering system 4 is arranged in parallel with the spring shock absorber 503.

[0063] like Figure 7 As shown: the suspension upper fork arm 501 is an A-shaped fork arm, the tip of the suspension upper fork arm 501 is provided with a vertical shaft hole 504, and the ends of the suspension upper fork arm 501 are respectively provided with a horizontal shaft hole 505; the vertical shaft hole 504 of the suspension upper fork arm 501 is hinged to the upper cross arm 406 of the steering knuckle 405 through a vertical pin shaft, as shown Figure 8 The transverse axis hole 505 at the end of the upper fork arm 501 of the suspension is respectively hinged to the inner wall of the new travel unit housing 6 through a transverse pin.

[0064] The disconnected suspension lower wishbone 502 includes a first single arm 506 and a second single arm 507; the first single arm 506 and the second single arm 507 are symmetrically arranged; one end of the first single arm 506 and the second single arm 507 are inclined toward each other, and the inclined end of the single arm is hinged to one end of the wishbone connector 508 through a transverse pin, and the other end of the wishbone connector 508 is hinged to the lower support arm 409 at the lower end of the steering knuckle 405 through a vertical pin; the other end of the single arm is hinged to the inner wall of the new travel unit shell 6 through a transverse pin; the intersection of the extension lines of the first single arm 506 and the second single arm 507 is located in the wheel hub 1, serving as the virtual steering kingpin lower positioning point; in this embodiment, the lower end of the spring shock absorber 503 is hinged to the second single arm 507.

[0065] like Figure 9As shown: the new travel unit shell 6 includes a suspension upper connecting wall 601, a suspension lower connecting wall 602, a frame upper connecting wall 603, a frame lower connecting wall 604 and a connector 605; the suspension upper connecting wall 601 and the suspension lower connecting wall 602 are both located on the inner side of the connector 605, and are respectively hinged to one end of the suspension upper fork arm 501 and the disconnected suspension lower fork arm 502; the frame upper connecting wall 603 and the frame lower connecting wall 604 are both located on the outer side of the connector 605, and are fixedly connected to the frame; the upper end of the spring shock absorber 503 is hinged to the upper end of the connector 605; the steering motor 401 and the recirculating ball steering gear 402 of the recirculating ball tie rod electronic steering system 4 are fixedly installed on the inner side of the connector 605.

[0066] Working principle of the present invention:

[0067] The present invention provides a novel driving unit based on an in-wheel motor, wherein the reduction-type in-wheel motor 2 and the electronic mechanical brake system 3 are arranged in the rim of the wheel hub 1, and the steering knuckle 405, the reduction-type in-wheel motor 2, the electronic mechanical brake system 3 and the wheel hub 1 are connected in sequence;

[0068] The reduction wheel hub motor 2 serves as a drive system, providing driving force for the new travel unit and regenerative braking force through motor reversal;

[0069] The electromechanical braking system 3 provides friction braking force for the new driving unit, and is combined with the deceleration-type wheel hub motor 2 that provides regenerative braking force to form a dual electric braking system;

[0070] The recirculating ball tie rod electric steering system 4 is connected to the drive system via the steering knuckle 405 and is used to perform large-angle steering with variable transmission ratio for the new travel unit;

[0071] The suspension upper fork arm 501 and the disconnected suspension lower fork arm 502 are respectively connected to the steering knuckle 405, forming a virtual steering kingpin upper positioning point and a virtual steering kingpin lower positioning point. The line connecting the virtual steering kingpin upper positioning point and the virtual steering kingpin lower positioning point constitutes a virtual steering kingpin, which releases the internal space of the wheel hub 1 for the arrangement of the reduction-type hub motor 2 and the electronic mechanical brake 3 to improve heat dissipation performance, and provides the steering system with a virtual steering kingpin with zero tire offset, thereby improving steering flexibility.

[0072] The planetary reducer 202 of the reduction-type hub motor 2 is completely embedded in the rotor support frame 205 of the hub motor 201. The input end of the planetary reducer 202 is connected to the rotor through-shaft 207 of the hub motor 201. The planetary reducer is driven by the rotor through-shaft 207 to form an extreme power density.

[0073] The stator housing 203 of the hub motor 201 plays a supporting and fixing role. The stator core and coil winding of the stator 204 provide field strength to drive the permanent magnet of the rotor 206 to rotate. The rotor 206 drives the rotor support frame 205 to rotate. The rotor support frame 205 drives the sun gear 211 of the planetary reducer 202 to rotate synchronously through the rotor through shaft 207; the sun gear 211 of the planetary reducer 202 is decelerated and torque-increased by the planetary gear 210 and the reducer ring gear 208, and outputs the torque to the brake disc 301, thereby driving the hub 1 to rotate.

[0074] The brake caliper 303 in the electronic mechanical brake system 3 has a fixing frame and brake pads, which are fixed to the reduction-type hub motor 2 through the fixing frame. The brake pads are arranged on both sides of the brake disc 301. The brake motor 302 drives the brake caliper 303 through the deceleration torque-increasing device and the motion conversion device. The brake pads are close to the brake disc 301 to generate friction to form a braking force, and the brake disc 301 drives the wheel hub 1 to decelerate.

[0075] The steering motor 401 in the recirculating ball-tie rod electronically controlled steering system 4 rotates the screw of the recirculating ball steering gear 402. The screw converts sliding friction into rolling friction through the recirculating balls, driving the nut to move horizontally and the gear fan to rotate. The gear fan of the recirculating ball steering gear 402 pushes the steering straight rod 404 by rotating the steering rocker arm 403, pulling the steering knuckle 405 to rotate the wheel; compared with other types of steering gears such as rack and pinion type and worm gear type, the recirculating ball steering gear 402 converts the translation of the steering gear output end into rotation, thereby greatly reducing the axial size of the steering system; the recirculating ball-tie rod electronically controlled steering system 4 is arranged in parallel with the spring shock absorber 503, which reduces the occupied space and improves the flexibility of the new type of unit.

[0076] The upper cross arm 406, vertical arm 407, connecting plate 408 and lower support arm 409 of the steering knuckle 405 are connected in sequence to form a Z-shaped steering knuckle 405; the hinge point between the upper cross arm 406 and the upper fork arm 501 of the suspension is located above the tire, serving as the upper positioning point of the virtual steering kingpin; the connecting plate 408 at the lower end of the steering knuckle 405 is rotatably connected to one end of the disconnected suspension lower fork arm 502 through two horizontally parallel lower support arms 409 through vertical pin shafts.

[0077] The suspension upper fork arm 501 is an A-shaped fork arm, the tip of which is hinged to the upper cross arm 406 of the steering knuckle 405 through a vertical pin shaft, and the end of which is hinged to the inner wall of the new travel unit housing 6, rather than being directly connected to the frame.

[0078] The two symmetrically arranged single arms of the disconnected suspension lower fork arm 502 are rotatably connected to the lower support arm 409 at the lower end of the steering knuckle 405 through the fork arm connector 508; the intersection of the extension lines of the two single arms is located inside the wheel hub 1, serving as the virtual steering kingpin lower positioning point; the disconnected suspension lower fork arm 502 shortens the axial dimension of the lower fork arm compared to the integral lower fork arm, while reducing the kingpin offset distance, freeing up the internal space of the wheel hub 1, thereby improving the structural compactness and steering operation flexibility of the new travel unit; combined with the spring shock absorber 503, it is used for buffering and shock absorption of the vehicle body.

[0079] The new running unit housing 6 is connected to the vehicle frame. As the only component connecting the new running unit and the vehicle frame, it minimizes the structural coupling effects between the various systems of the new running unit and the vehicle frame, thereby improving the portability of the new running unit between different vehicle models and the degree of freedom in vehicle body space design.

[0080] The working process of the present invention:

[0081] During driving, the stator housing 203 is a fixed part, and the permanent magnet of the rotor 206 is acted upon by the magnetic field formed by the motor winding and the stator core, driving the rotor 206 to rotate synchronously. The rotor 206 is integrated with the planetary reducer through the rotor through-shaft 207, and the driving torque is transmitted to the wheel hub 1 after being decelerated and amplified by the planetary reducer, providing driving force to drive the new travel unit.

[0082] During braking, the braking force of the new travel unit comes from two sources: the regenerative braking force provided by the in-wheel motor 201 and the friction braking force provided by the electronic mechanical brake system 3. On the one hand, the regenerative braking force is generated by the reverse driving process of the in-wheel motor 201. On the other hand, the electronic mechanical brake system 3 in the wheel hub 1 cavity pushes the brake pads of the brake caliper 303 to clamp the brake disc 301 through the brake motor 302, generating friction braking force. The regenerative braking force generated by the in-wheel motor 201 and the friction braking force generated by the brake disc 301 are transmitted to the tire through the wheel hub 1. The two work together to generate ground braking force at the tire to brake the new travel unit and decelerate.

[0083] During steering, after receiving the steering angle signal from the controller, the steering motor 401 transmits the steering torque to the screw of the recirculating ball steering gear 402 through the output shaft. After the recirculating ball steering gear 402 changes the transmission ratio and direction, the gear fan rotates the steering rocker arm 403 and drives the steering straight rod 404. The steering straight rod 404 pushes and pulls the steering knuckle 405 to realize the rotation of the wheel around the virtual steering kingpin with zero kingpin offset inside the wheel;

[0084] When the wheel bounces, the suspension upper fork arm 501, the disconnected suspension lower fork arm 502 and the novel travel unit housing 6 can rotate freely relative to each other, and bounce normally after being buffered and damped by the spring shock absorber 503.

Claims

1. A new driving unit based on a hub motor, characterized by: The invention comprises a wheel hub, a reduction wheel hub motor, an electronic mechanical braking system, a recirculating ball tie rod electronically controlled steering system, a disconnected double wishbone suspension and a new travel unit housing; a tire is provided on the outside of the wheel hub rim; the reduction wheel hub motor and the electronic mechanical braking system are arranged inside the wheel hub rim; the reduction wheel hub motor comprises a wheel hub motor and a planetary reducer, the planetary reducer is embedded in the wheel hub motor, and the input end of the planetary reducer is connected to the rotor through-shaft of the wheel hub motor; the fixed end of the reduction wheel hub motor is fixedly connected to the lower end of the steering knuckle of the recirculating ball tie rod electronically controlled steering system, the rotating end of the reduction wheel hub motor is fixedly connected to one end of the brake disc of the electronic mechanical braking system, and the other end of the brake disc is fixedly connected to the wheel hub; the electronic mechanical braking system comprises a brake disc, a brake motor and a brake caliper, the brake motor and the brake caliper are fixedly connected to the wheel hub motor, the brake motor is transmission-connected to the brake caliper, and the brake caliper is sleeved on the side of the brake disc; the recirculating ball tie rod electronically controlled steering system comprises a steering motor, a recirculating ball steering gear, a steering rocker arm, a steering straight rod and a steering knuckle, the The steering motor and the recirculating ball steering gear are fixedly connected to the inner side of the new travel unit housing. The steering motor, the recirculating ball steering gear, the steering rocker arm and the steering straight rod are connected in sequence. The steering straight rod is hinged to one side of the steering knuckle. The disconnected double wishbone suspension includes an upper fork arm, a disconnected suspension lower fork arm and a spring shock absorber. The upper end of the steering knuckle is hinged to one end of the upper fork arm of the suspension. The hinge point is located above the wheel hub and serves as the upper positioning point of the virtual steering kingpin. The lower end of the steering knuckle is hinged to one end of the disconnected suspension lower fork arm. The intersection of the extension lines of the arms is located inside the wheel hub and serves as the lower positioning point of the virtual steering kingpin; the other end of the upper fork arm of the suspension is hinged to the upper part of the new travel unit shell; the other end of the lower fork arm of the disconnected suspension is hinged to the lower part of the new travel unit shell; the upper end of the spring shock absorber is hinged to the upper end of the new travel unit shell, and the lower end of the spring shock absorber is hinged to one of the fork arms of the disconnected suspension lower fork arm; the recirculating ball tie rod electronic steering system and the spring shock absorber are arranged in parallel; the outer side of the new travel unit shell is connected to the vehicle frame.

2. The novel driving unit based on the in-wheel motor according to claim 1 is characterized in that: The hub motor includes a stator shell, a stator, a rotor support frame and a rotor; the stator shell is a hollow cylindrical tube structure with an open end, and a bearing hole is provided in the center of the other end surface; the stator shell is fixedly connected to the lower end of the steering knuckle as the fixed end of the reduction-type hub motor; the stator, rotor support frame and rotor are respectively arranged inside the stator shell; the stator is arranged on the inner ring of the stator shell, and the stator includes a stator core and a coil winding wound on the stator core; the rotor support frame is a hollow cylindrical tube structure with an open end, and a rotor through-shaft is provided in the center; the rotor support frame is coaxially arranged on the inner ring of the stator, and a gap is provided between the rotor and the stator; one end of the rotor through-shaft extends from the closed end of the rotor support frame and is pivotally connected to the bearing hole of the stator shell; the other end of the rotor through-shaft is coaxially fixed to the sun gear of the planetary reducer; the rotor is arranged on the outer ring of the rotor support frame, and a gap is provided between the rotor and the stator; the rotor is a permanent magnet.

3. The novel driving unit based on the in-wheel motor according to claim 1 is characterized in that: The planetary reducer includes a reducer ring gear, a planetary carrier, planetary wheels and a sun gear; the reducer ring gear is pivotally connected to the open end of the stator housing of the hub motor through a bearing, and the reducer ring gear serves as the rotating end of the reduction-type hub motor, and its outer side is fixedly connected to the brake disc of the electronic mechanical brake; the planetary carrier is arranged on the inner side of the reducer ring gear, and the planetary wheels are pivotally connected to the planetary carrier and meshed with the reducer ring gear; the sun gear is arranged at the center of the reducer ring gear and meshes with each planetary gear; the sun gear serves as the input end of the planetary reducer and is coaxially fixed to the rotor through-axis.

4. The novel driving unit based on the in-wheel motor according to claim 1 is characterized in that: The steering knuckle includes an upper transverse arm, a vertical arm, a connecting plate and a lower support arm; the upper transverse arm, the vertical arm, the connecting plate and the lower support arm are connected in sequence to form a Z-type steering knuckle; the upper transverse arm is hinged to one end of the upper fork arm of the suspension through a vertical pin shaft, and the hinge point is located above the tire, serving as a positioning point on the virtual steering kingpin; the lower end of the vertical arm is provided with a connecting plate, which is connected to the fixed end of the reduction type hub motor through the connecting plate; a steering support arm is also provided on one side of the connecting plate, and the steering support arm is hinged to the steering straight pull rod of the recirculating ball tie rod electronic steering system; the lower end of the connecting plate is provided with two lower support arms arranged in parallel in the horizontal direction, and the two lower support arms are respectively hinged to one end of the lower fork arm of the disconnected suspension through a vertical pin shaft.

5. The novel driving unit based on the in-wheel motor according to claim 1 is characterized in that: The upper fork arm of the suspension is an A-shaped fork arm, the tip of the upper fork arm of the suspension is provided with a vertical axis hole, and the ends of the upper fork arm of the suspension are respectively provided with transverse axis holes; the vertical axis hole of the upper fork arm of the suspension is hinged to the upper cross arm of the steering knuckle through a vertical pin shaft; the transverse axis holes at the ends of the upper fork arm of the suspension are respectively hinged to the upper connecting wall of the suspension on the inner side of the new travel unit shell through transverse pin shafts.

6. The novel driving unit based on the in-wheel motor according to claim 1 is characterized in that: The disconnected suspension lower wishbone includes two symmetrically arranged single arms, one end of the two single arms is inclined toward each other, the inclined end of the single arm is hinged to one end of the wishbone connecting member through a transverse pin, and the other end of the wishbone connecting member is hinged to the lower support arm at the lower end of the steering knuckle through a vertical pin; the other end of the single arm is hinged to the suspension lower connecting wall on the inner side of the new travel unit shell through a transverse pin; the intersection of the extension lines of the two single arms is located inside the wheel hub, serving as the virtual steering kingpin lower positioning point.

7. The novel driving unit based on the in-wheel motor according to claim 1 is characterized in that: The new travel unit shell includes an upper connecting wall of the suspension, a lower connecting wall of the suspension, an upper connecting wall of the frame, a lower connecting wall of the frame and a connector; the upper connecting wall of the suspension and the lower connecting wall of the suspension are both located on the inside of the connector and are respectively hinged to one end of the upper fork arm of the suspension and the disconnected lower fork arm of the suspension; the upper connecting wall of the frame and the lower connecting wall of the frame are both located on the outside of the connector and are fixedly connected to the frame; the upper end of the spring shock absorber is hinged to the upper end of the connector; the steering motor and the recirculating ball steering gear of the recirculating ball tie rod electronic steering system are fixedly installed on the inside of the connector.

Images