Energy-saving electric vehicle motor with speed limiting function

Abstract

This invention relates to the field of motor technology, specifically to an energy-saving electric vehicle motor with speed limiting function, comprising a wheel hub, and a motor assembly and controller frame integrated within the wheel hub; the motor assembly includes a motor stator and a rotor, and the controller frame is used to drive the motor assembly to operate; a mechanical speed limiting mechanism includes a displacement component and a friction component; the displacement component includes a stator connecting frame that can push and pull the motor stator to move within the controller frame, and radially movable centrifugal hammers and a preload spring that provides a reset preload force for them, the centrifugal hammers being driven by centrifugal force to drive the stator connecting frame to move when the wheel hub speed increases; the friction component is linked with the centrifugal hammers and is configured to generate frictional resistance with the displacement component, generating frictional heat when the wheel hub overspeeds; a heat energy recovery and utilization system includes a heat transfer pipe and a lubricant chamber, the lubricant chamber being used to contain lubricant and receiving heat generated by the friction component through the heat transfer pipe to preheat the lubricant.

Description

Technical Field

[0001] This invention relates to the field of motor technology, specifically to an energy-saving electric vehicle motor with a speed-limiting function. Background Technology

[0002] With the widespread adoption of electric vehicles, the performance, safety, and energy efficiency of their drive motors have become key concerns. Among these, speed limiting functions to prevent overspeeding are crucial for ensuring driving safety, while improving energy utilization efficiency is fundamental to extending driving range and reducing operating costs.

[0003] In practical applications of in-wheel motors, one of the core functions ensuring vehicle safety is the reliable limitation of their maximum speed. Currently, the main technical means of achieving speed limiting in-wheel motors rely on electronic control systems, which can be divided into two paths: one is to preset software programs in the motor controller to limit the output current or PWM duty cycle; the other is to form a closed loop through speed sensor feedback to dynamically adjust the power output. While these electronic speed limiting schemes offer rapid response and precise control, their safety depends entirely on the reliability of the electronic system. However, in actual use, there are instances where users maliciously crack or remove the electronic speed limiting function through unofficial means (such as "flashing" the controller program or replacing it with a high-power controller), leading to vehicle overspeeding and causing serious safety hazards and compliance risks. Furthermore, the electronic control system itself may also fail due to component failure, electromagnetic interference, or software vulnerabilities, posing a potential danger of "runaway" vehicles.

[0004] To enhance safety, some solutions attempt to introduce mechanical speed limiters as a redundancy backup. Common mechanical speed limiters, such as centrifugal friction speed limiters, use centrifugal force to trigger friction blocks to contact rotating components, generating resistance. This type of purely mechanical structure does not rely on circuitry and is theoretically impossible to tamper with via software, possessing high inherent reliability. However, existing mechanical speed limiter solutions have significant drawbacks: First, their operation is usually limited to simple friction braking, crudely converting the vehicle's kinetic energy into heat dissipation. This not only wastes energy, contradicting the energy-saving principles of electric vehicles, but may also affect the lifespan and reliability of the motor or other components due to localized overheating; second, their function is singular, passively triggered only when exceeding the speed limit, remaining idle for most of the vehicle's normal operating time, without adding any value to the overall vehicle performance; finally, their intervention is often not smooth enough, potentially affecting the driving experience.

[0005] As described in patent document CN118402166A, this patent document provides a hub motor capable of preventing magnet demagnetization due to thermal effects from friction brakes. The hub motor is an external rotor type hub motor comprising: a stator having coils; and a rotor having magnets opposite the coils and rotating relative to the stator about a motor shaft. In this hub motor, the rotor further comprises: a rotor housing holding the magnets; and a brake disc connected to the inner end of the rotor housing in the wheel width direction and rotating together with the rotor housing. The rotor housing and the brake disc are connected to each other by means of a heat-capacity member.

[0006] While existing technologies effectively suppress rotor housing temperature rise and prevent irreversible demagnetization of permanent magnets due to high temperatures through drive plate heat storage structures, this thermal management strategy suffers from significant environmental adaptability deficiencies. During operation in cold regions, the waste heat generated by the motor is confined to the drive plate area and cannot be directed to low-temperature sensitive parts such as the bearing cavity. Due to the lack of an active heat flow path control mechanism, the fluidity of the bearing lubricant deteriorates severely in low-temperature environments, making it difficult to form an effective lubricating film. This leads to a significant increase in cold-start resistance, frequent abnormal noises during operation, and even the risk of dry friction wear or momentary jamming of the bearing. Therefore, this application proposes an energy-saving electric vehicle motor with speed-limiting functionality. Summary of the Invention

[0007] The purpose of this invention is to provide an energy-saving electric vehicle motor with a speed-limiting function to solve the problems mentioned in the background art.

[0008] To achieve the above objectives, the present invention provides the following technical solution: an energy-saving electric vehicle motor with speed-limiting function, comprising a wheel hub, and further comprising: Motor assembly and controller bracket integrated into the wheel hub; The motor assembly includes a motor stator and a rotor, and the controller frame is used to drive the motor assembly to operate. A mechanical speed limiter, comprising a displacement component and a friction component; The displacement assembly includes a stator frame that can push and pull the motor stator to move within the controller frame, and radially movable centrifugal hammers and a preload spring that provides a reset preload force for them. The centrifugal hammers are driven by centrifugal force to move the stator frame when the hub speed increases. The friction component is linked with the centrifugal hammer ball and is configured to generate frictional resistance with the displacement component, and generate frictional heat when the hub overspeeds. A heat recovery and utilization system includes a heat transfer pipe and a lubricant chamber. The lubricant chamber is used to contain lubricant and receives heat generated by the friction assembly through the heat transfer pipe to preheat the lubricant.

[0009] Preferably, the friction assembly further includes a ring frame fixedly connected to the stator frame and friction balls rotating with the hub. An arc plate is fixedly connected to one side of the ring frame, and a gradually widening friction plate is fixedly connected to the surface of the arc plate. The friction balls engage with the gradually widening friction plate under the drive of the displacement assembly to generate friction braking force.

[0010] Preferably, the displacement assembly further includes a crank, the two ends of which are respectively connected to centrifugal hammer balls and friction balls, and a bracket for crank swinging is fixedly connected inside the hub.

[0011] Preferably, the heat energy recovery and utilization system further includes multiple heat-conducting pipes connected to the lubricant preheating chamber. The heat-conducting pipes are fixedly connected to the gradually widening friction plate. A heat transfer pipe is fixedly connected inside the heat-conducting pipe. The first end of the heat transfer pipe is thermally connected to the friction area of ​​the gradually widening friction plate, and the second end is thermally connected to the lubricant preheating chamber. The lubricant preheating chamber is connected to the lubricant chamber through a transmission hose.

[0012] Preferably, it also includes a shock-absorbing assembly and a cooling assembly. The shock-absorbing assembly includes a compressor housing fixedly connected to the inside of the crank and a piston rod slidably disposed in the compressor housing. The outer surface of the friction ball is provided with a collar for it to roll. The end of the piston rod away from the compressor housing is fixedly connected to the collar. A spring for driving the piston rod to return to its original position is fixedly connected inside the compressor housing.

[0013] Preferably, the cooling assembly includes an inlet check valve and an outlet check valve respectively connected to both sides of the compressor housing. The inlet check valve allows external gas to enter the compressor housing, and the outlet check valve allows gas inside the compressor housing to exit. The exhaust end of the outlet check valve is connected to an air inlet.

[0014] Preferably, a connecting frame is fixedly connected to the inner wall of the hub, and a rotor frame for supporting the rotor is fixedly connected inside the hub. The connecting frame is connected to the main shaft through bearings.

[0015] Preferably, it also includes a main shaft fixedly connected to the controller frame, and the controller frame has a sliding groove for the motor stator to slide inside.

[0016] Preferably, a telescopic rod is fixedly connected inside the controller frame, the telescopic end of the telescopic rod is fixedly connected to the stator connecting frame, and a return spring for driving the telescopic rod to return to its original position is sleeved on the outer surface of the telescopic rod.

[0017] Preferably, multiple fan blades are fixedly connected to the inner wall of the rotor frame, heat dissipation holes are provided inside the connecting frame, and a brake pad is fixedly connected to one side of the hub.

[0018] Compared with the prior art, the beneficial effects of the present invention are: 1. As the hub speed increases, the centrifugal hammer ball is driven by centrifugal force to overcome the preload of the preload spring, pushing the crank to swing around the support, which in turn drives the stator connecting frame to move axially along the telescopic rod. This gradually reduces the overlap area (overlap ratio) of the magnetic poles of the motor stator and rotor, causing the electromagnetic torque to naturally decay and achieving the first level of smooth speed limiting. As the speed continues to climb, the crank swing angle increases, driving the friction balls to press against the gradually widening friction plate on the arc plate surface. The positive pressure increases significantly with the gradually widening design, and the friction torque surges by a certain percentage, forcibly decelerating to the safety threshold. This solves the industry pain point, ensures the speed limit is tamper-proof, and avoids the risk of electronic hacking through pure mechanical centrifugal drive (centrifugal hammer ball, preload spring).

[0019] 2. By precisely integrating vibration damping and cooling components, a deep synergy between vibration energy regeneration and thermal management is achieved, forming an active energy closed loop of vibration, airflow, and cooling: When the friction balls and the gradually widening friction plates come into contact and generate high-frequency vibration, the vibration force is transmitted to the piston rod through the collar, driving it to reciprocate within the compressor housing. When retracting, the spring is compressed and the intake check valve is opened to draw in cold air. When pushing forward, the intake check valve is closed and the exhaust check valve is opened, directing the compressed gas through the air nozzle to the stator windings and rotor air gap area of ​​the motor. At the same time, the hub rotation drives the fan blades to rotate at high speed, forming the main airflow, which passes through the heat dissipation holes and penetrates the motor cavity. It works in conjunction with the pulsed airflow ejected from the air nozzle in the stator area to form turbulent enhanced heat transfer, realizing the conversion of vibration energy into cooling airflow, reducing the temperature of the motor stator windings, and effectively suppressing the increase in copper loss and the risk of permanent magnet demagnetization caused by temperature rise. Meanwhile, frictional heat is precisely maintained within the optimal range of 15–25℃ through a closed-loop path consisting of a gradually widening friction plate, heat conduction pipe, heat transfer pipe, lubricant preheating chamber, transmission hose, and lubricant chamber. This reduces the low-temperature starting resistance torque. Vibration energy is converted into cooling power; cooling relies on external energy, achieving self-powered cooling; and the air nozzle and fan blades work together to form a directional airflow, improving the stator temperature rise suppression rate. Attached Figure Description

[0020] Figure 1 This is a three-dimensional structural diagram of the present invention; Figure 2 This is a partial cross-sectional structural diagram of the hub in this invention; Figure 3 For the present invention Figure 2 Enlarged structural diagram at point A; Figure 4 This is a schematic cross-sectional view of the hub structure in this invention; Figure 5 For the present invention Figure 4 Enlarged structural diagram at point B; Figure 6 This is an exploded structural diagram of the hub, motor stator, and main shaft in this invention; Figure 7This is an exploded structural diagram of the motor stator and rotor in this invention; Figure 8 This is a schematic cross-sectional view of the spindle in this invention; Figure 9 This is a cross-sectional view of the controller frame in this invention. Figure 10 This is a partial cross-sectional structural diagram of the rotor frame in this invention; Figure 11 For the present invention Figure 10 Enlarged schematic diagram of the structure at point C; Figure 12 This is a schematic diagram of the crank mechanism in this invention; Figure 13 This is a schematic cross-sectional view of the compressed air shell in this invention.

[0021] In the diagram: 100, hub; 101, brake pad; 102, main shaft; 103, connecting frame; 104, rotor frame; 105, bearing; 106, controller frame; 107, motor stator; 108, rotor; 109, heat dissipation hole; 110, fan blade; 200, stator connecting frame; 201, telescopic rod; 202, return spring; 203, ring frame; 204, crank; 205, bracket; 206, friction. 207. Ball bearing; 208. Arc plate; 209. Centrifugal ball bearing; 300. Preload spring; 301. Gradually widening friction plate; 302. Heat pipe; 303. Lubricant preheating chamber; 304. Heat transfer pipe; 305. Transfer hose; 306. Lubricant chamber; 407. Air inlet; 408. Compressor housing; 409. Piston rod; 400. Collar; 401. Spring; 402. Inlet check valve; 403. Outlet check valve. Detailed Implementation

[0022] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0023] Example 1: Please refer to Figure 1 - Figure 13 The present invention provides a technical solution: an energy-saving electric vehicle motor with speed limiting function, including a wheel hub 100, the wheel hub 100 being an integral cast aluminum alloy structure, and further including: Motor assembly and controller bracket 106 integrated within wheel hub 100; The motor assembly includes a stator 107 and a rotor 108. A controller frame 106 drives the motor assembly. A connecting frame 103 is fixedly connected to the inner wall of the hub 100. A rotor frame 104 for supporting the rotor 108 is fixedly connected inside the hub 100. The connecting frame 103 is connected to the main shaft 102 via bearings 105. Three-phase armature windings are wound on the motor stator 107, and permanent magnets are built into the rotor 108. The controller frame 106 is fixedly installed inside the hub 100 and integrates an electronic controller. It is used to supply alternating current to the three-phase windings of the motor stator 107 in a specific sequence to generate a rotating magnetic field to drive the rotor 108 to rotate, thereby ultimately driving the hub 100 to rotate. A mechanical speed limiter, comprising a displacement component and a friction component; The displacement assembly includes a stator connecting frame 200 that allows the motor stator 107 to move within the controller frame 106, a main shaft 102 fixedly connected to the controller frame 106, a sliding groove for the motor stator 107 to slide within the controller frame 106, allowing the stator connecting frame 200 to drive the motor stator 107 to slide within the groove, a radially movable centrifugal hammer ball 208 and a preload spring 209 that provides a reset preload force for it, the centrifugal hammer ball 208 being driven by centrifugal force when the speed of the hub 100 increases, thereby driving the stator connecting frame 200 to move; When the speed of hub 100 is <24km / h, the centrifugal hammer ball 208 is subjected to centrifugal force F<25N, which does not overcome the preload force of preload spring 209. The first-level speed limit trigger is 24km / h≤speed ≤26km / h: the speed increases so that F>25N, the centrifugal hammer ball 208 moves radially outward and pushes crank 204 to swing. Through ring frame 203, it pulls stator connecting frame 200 to slide along telescopic rod 201, and the overlapping area of ​​magnetic poles of motor stator 107 and rotor 108 decreases. The friction assembly is linked with the centrifugal hammer ball 208 and is configured to generate frictional resistance with the displacement assembly, and generate frictional heat when the hub 100 overspeeds. After the first-level speed limit, the overspeed speed is >26km / h: the displacement of the centrifugal hammer ball 208 increases, the swing angle of the crank 204 increases, the friction ball 206 is pressed towards the wide end of the gradually widening friction plate 300, and the increase in normal pressure significantly increases the friction force. The heat recovery and utilization system includes a heat transfer pipe 303 and a lubricant chamber 305. The lubricant chamber 305 is used to contain lubricant and receives heat generated by the friction assembly through the heat transfer pipe 303 to preheat the lubricant.

[0024] Furthermore, the friction assembly also includes a ring frame 203 fixedly connected to the stator connecting frame 200 and friction balls 206 rotating with the hub 100. An arc plate 207 is fixedly connected to one side of the ring frame 203, and a gradually widening friction plate 300 is fixedly connected to the surface of the arc plate 207. The friction balls 206 engage with the gradually widening friction plate 300 under the drive of the displacement assembly to generate friction braking force.

[0025] Furthermore, the displacement assembly also includes a crank 204, whose two ends are respectively connected to centrifugal hammer balls 208 and friction balls 206. A bracket 205 for swinging the crank 204 is fixedly connected inside the hub 100. A telescopic rod 201 is fixedly connected inside the controller frame 106. The telescopic end of the telescopic rod 201 is fixedly connected to the stator connecting frame 200. A return spring 202 for driving the telescopic rod 201 to reset is sleeved on the outer surface of the telescopic rod 201. By setting the telescopic rod 201, the stator connecting frame 200 can be guided to avoid misalignment. At the same time, the return spring 202 can effectively drive the stator connecting frame 200 to reset, which facilitates subsequent displacement.

[0026] Furthermore, the heat energy recovery and utilization system also includes multiple heat conduction pipes 301 connected to the lubricant preheating chamber 302. The heat conduction pipes 301 are fixedly connected to the gradually widening friction plate 300. A heat transfer pipe 303 is fixedly connected inside the heat conduction pipe 301. The first end of the heat transfer pipe 303 is thermally connected to the friction area of ​​the gradually widening friction plate 300, and the second end is thermally connected to the lubricant preheating chamber 302. The lubricant preheating chamber 302 is connected to the lubricant chamber 305 through a transmission hose 304.

[0027] Easily bypassed: Electronic speed limiting schemes rely on software control, allowing users to bypass speed limits by cutting speed limit lines or flashing controller firmware. Data from a special inspection by the State Administration for Market Regulation in 2022 showed that modified vehicles exceeding speed limits accounted for as high as 34.7%, rendering the safety speed limit ineffective.

[0028] Some users modify the controller, such as through so-called "hacking" or "flashing," to increase the motor's output power, thereby bypassing the vehicle's factory-set electronic speed limit. This makes the speed limit function completely independent of the potentially tampered electronic control system, turning it into an unalterable "mechanical safety bolt" based on purely physical principles such as centrifugal force. During normal motor operation, the electronic controller drives the motor stator 107 to generate a rotating magnetic field, which in turn drives the rotor 108 and the hub 100 to rotate. When the hub 100 speed increases to a set threshold, such as 24 km / h, the centrifugal hammer ball 208, under the action of centrifugal force, overcomes the preload of the preload spring 209 and slides radially outward, pushing the crank 204 to swing around the bracket 205, causing the friction ball 206 to roll along the top surface of the arc plate 207 and press against the gradually widening friction plate 300. At the same time, the swing of the crank 204 pulls the stator connecting frame 200 to move axially along the telescopic rod 201 through the ring frame 203, so that the magnetic pole overlap area of ​​the motor stator 107 and rotor 108, i.e., the "overlap ratio", gradually decreases, and the electromagnetic torque naturally decays, thus achieving speed limiting.

[0029] Specifically, the electronic controller inside the controller frame 106 operates normally, driving the stator 107 and rotor 108 of the motor to generate torque, which drives the hub 100 to rotate. At this time, the centrifugal force of the centrifugal hammer 208 does not overcome the preload of the preload spring 209, and the speed limiting mechanism does not operate.

[0030] First-level speed limiting changes the overlap: When the speed of hub 100 increases abnormally, such as due to electronic controller failure causing "runaway," the centrifugal force on centrifugal ball bearing 208 increases, overcoming the preload force of preload spring 209 and moving outward. Centrifugal ball bearing 208 pushes one end of crank 204, causing crank 204 to swing around bracket 205. The other end of crank 204 pushes friction ball bearing 206 upward and radially inward, compressing the top surface of arc plate 207. Since arc plate 207 is fixed to stator connecting frame 200 through ring frame 203, this force pushes stator connecting frame 200 to slide axially over the elastic force of return spring 202, thereby driving motor stator 107 on it to move axially, resulting in a decrease in the electromagnetic coupling overlap between motor stator 107 and rotor 108. The magnetic circuit reluctance increases, the motor output torque capability decreases, and the first-level smooth speed limiting is achieved.

[0031] Friction Braking and Heat Recovery: If the speed continues to rise after the first-level speed limit, indicating a severe fault, the displacement of the centrifugal hammer ball 208 will be greater, and the swing angle of the crank 204 will increase, causing the friction balls 206 to be pressed more forcefully against the gradually widening friction plate 300. Due to the "widening" design of the inclined or curved surface of the gradually widening friction plate 300, the downward pressure on the friction balls 206 increases significantly with the increase in displacement. A huge frictional braking force is generated between the rotating friction balls 206 and the stationary gradually widening friction plate 300, forcibly decelerating the hub 100 and achieving the second-level speed limit.

[0032] In summary, as the speed of hub 100 increases, centrifugal hammers 208 are driven by centrifugal force to overcome the preload of preload spring 209, pushing crank 204 to swing around bracket 205, which in turn drives stator connecting frame 200 to move axially along telescopic rod 201. This gradually reduces the overlap of magnetic poles between motor stator 107 and rotor 108, causing electromagnetic torque to naturally decrease and achieving the first level of smooth speed limiting. As the speed continues to increase, the swing angle of crank 204 increases, driving friction balls 206 to press against the gradually widening friction plate 300 on the surface of arc plate 207. The positive pressure increases significantly with the gradually widening design, and the friction torque surges by 300%, forcibly decelerating to a safe threshold. This solves industry pain points, ensures the speed limit is tamper-proof, and avoids the risk of electronic hacking by using purely mechanical centrifugal drive centrifugal hammers 208 and preload spring 209.

[0033] Example 2: Please refer to Figure 1 - Figure 13 The present invention also provides a technical solution, which differs from the technical solution of embodiment one as follows: an energy-saving electric vehicle motor with speed limiting function, which further includes a shock absorption component and a cooling component. The shock absorption component includes a compressor housing 401 fixedly connected inside the crank 204 and a piston rod 402 slidably disposed inside the compressor housing 401. The outer surface of the friction ball 206 is provided with a collar 403 for rolling. The end of the piston rod 402 away from the compressor housing 401 is fixedly connected to the collar 403. A spring 404 for driving the piston rod 402 to return to its original position is fixedly connected inside the compressor housing 401.

[0034] Furthermore, the cooling assembly includes an inlet check valve 405 and an outlet check valve 406 respectively connected to both sides of the compressor housing 401. The inlet check valve 405 allows external gas to enter the compressor housing 401, and the outlet check valve 406 allows gas to be discharged from the compressor housing 401. The exhaust end of the outlet check valve 406 is connected to an air supply nozzle 400.

[0035] The vibration force is transmitted to the piston rod 402 via the collar 403, and the piston rod 402 reciprocates within the air compressor housing 401 for a stroke of 12 mm. Retraction phase: The piston rod 402 moves into the air chamber 401, the compression spring 404 and the air intake check valve 405 open, drawing in external cold air; Forward push phase: Spring 404 returns to its original position, piston rod 402 moves outward, intake check valve 405 closes, exhaust check valve 406 opens, and compressed air is ejected through air nozzle 400.

[0036] The piston rod 402 reciprocates, the inlet check valve 405 and the outlet check valve 406 open and close periodically, and the air supply nozzle 400 outputs pulsed airflow. The pulsed airflow is directionally ejected through the air supply nozzle 400 and exits from the air gap between the stator winding 107 and the rotor 108 of the motor.

[0037] Furthermore, multiple fan blades 110 are fixedly connected to the inner wall of the rotor frame 104, heat dissipation holes 109 are opened inside the connecting frame 103, and brake pads 101 are fixedly connected to one side of the hub 100.

[0038] The friction ball 206 and the gradually widening friction plate 300 generate braking force through friction. The frictional heat is transferred through the heat conduction pipe 301, the heat transfer pipe 303, the lubricant preheating chamber 302, the transmission hose 304, and the lubricant chamber 305. Specifically, a large frictional braking force is generated between the friction ball 206 and the stationary gradually widening friction plate 300. This process generates a large amount of frictional heat, which is conducted through the gradually widening friction plate 300 to the heat conduction pipe 301 and the internal heat transfer pipe 303, and then transported to the lubricant preheating chamber 302 to preheat the lubricant inside. The preheated lubricant can be circulated through the transmission hose 304 or directly conducted to the bearing 105 area, allowing the lubricant to quickly reach its optimal working viscosity even at low temperatures, reducing starting wear. At the same time, when the friction ball 206 contacts the gradually widening friction plate 300 and generates friction, vibration is produced. The vibration force on the friction ball 206 acts on the piston rod 402, causing it to move closer to the compressor housing 401 and compress the spring 404. The movement of the piston rod 402 absorbs the vibration generated by the friction ball 206. When the piston rod 402 reciprocates, it drives the intake check valve 405 to draw in air. The air drawn in by the intake check valve 405 enters the compressor housing 401 and is squeezed by the piston end of the piston rod 402 and discharged through the exhaust check valve 406. Subsequently, the exhaust check valve 406 is connected to the air supply nozzle 400 and the supplied air is discharged through the air supply nozzle 400. When the hub 100 rotates, it drives the fan blade 110 to rotate and form an airflow. Under the action of the air supply nozzle 400, the airflow is guided to achieve cooling of the motor stator 107 and rotor 108.

[0039] The reciprocating motion of the piston rod 402 constitutes a miniature air pump. When it pulls back, the intake check valve 405 opens, drawing in cooler outside air; when it pushes forward, the exhaust check valve 406 opens, forcefully expelling compressed air through the air outlet 400. Simultaneously, the rotation of the hub 100 drives the fan blades 110 to rotate, creating a directional airflow inside the hub 100. The high-speed airflow ejected from the air outlet 400 is precisely guided in this basic flow field, directly blowing onto the heat-generating core components such as the motor stator 107 and rotor 108, and forming convection with the air entering from the heat dissipation hole 109, greatly enhancing the motor's heat dissipation capacity under high load or braking conditions.

[0040] When the friction ball 206 contacts the gradually widening friction plate 300 and generates high-frequency vibration, the vibration is transmitted to the piston rod 402 through the collar 403, driving it to slide back and forth in the air compressor housing 401. When the piston rod 402 retracts, the spring 404 is compressed and stores energy, and at the same time, the intake check valve 405 opens to draw in external cold air. When the piston rod 402 pushes forward, the intake check valve 405 closes and the exhaust check valve 406 opens, and the compressed gas is directed through the air nozzle 400 to the stator winding 107 and the air gap area of ​​the rotor 108. At the same time, the hub 100 rotates, driving the fan blade 110 to rotate at high speed, forming a main airflow that passes through the heat dissipation hole 109 and penetrates the motor cavity. The pulsed airflow ejected from the air nozzle 400 and the continuous airflow generated by the fan blade 110 work together to enhance the forced air cooling effect on the stator winding, permanent magnet and friction area, effectively suppressing temperature rise and avoiding efficiency decay and material aging caused by heat accumulation. Vibrational energy is converted into beneficial airflow energy during this process, realizing the energy recycling of "vibration-based refrigeration".

[0041] In summary, by precisely integrating vibration damping and cooling components, a deep synergy between vibration energy regeneration and thermal management is achieved, forming an active energy closed loop of vibration, airflow, and cooling: When the friction ball 206 contacts the gradually widening friction plate 300 and generates high-frequency vibration, the vibration force is transmitted to the piston rod 402 via the collar 403, driving it to reciprocate within the compressor housing 401. During retraction, the spring 404 is compressed and the intake check valve 405 is opened to draw in cold air; during forward thrust, the intake check valve 405 is closed and the exhaust check valve is opened. Valve 406 directs compressed gas through the air nozzle 400 to the stator 107 winding and the air gap area of ​​the rotor 108 of the motor. At the same time, the hub 100 rotates, driving the fan blades 110 to rotate at high speed to form the main airflow. The airflow passes through the heat dissipation hole 109 and penetrates the motor cavity. It works in conjunction with the pulsed airflow ejected from the air nozzle 400 in the stator 107 area to form turbulent heat transfer, realizing the conversion of vibration energy into cooling airflow. This reduces the temperature of the stator 107 winding and effectively suppresses the increase in copper loss and the risk of permanent magnet demagnetization caused by temperature rise. Meanwhile, the frictional heat is precisely maintained within the optimal range of 15–25℃ for the bearing grease through a closed-loop path consisting of the gradually widening friction plate 300, heat conduction pipe 301, heat transfer pipe 303, lubricant preheating chamber 302, transmission hose 304, and lubricant chamber 305. This reduces the low-temperature starting resistance torque, where vibration energy is converted into cooling power. Cooling relies on external energy, achieving self-powered cooling. The air nozzle 400 and fan blade 110 work together to form a directional airflow, thereby improving the temperature rise suppression rate of the stator 107.

[0042] Working principle: The motor stator 107 is wound with three-phase armature windings, the rotor 108 has built-in permanent magnets, and the electronic controller built into the controller frame 106 runs to pass alternating current to the three-phase windings of the motor stator 107 in a specific sequence, thereby driving the rotor 108 to rotate and causing the hub 100 to rotate according to the magnetic field. As the rotational speed of hub 100 gradually increases, under the action of centrifugal force, centrifugal hammer ball 208 will be driven to move and overcome the preload of preload spring 209, causing crank 204 to tilt so that friction ball 206 can press the top surface of arc plate 207. At this time, ring frame 203 will be moved by force, causing stator connecting frame 200 to slide on the surface of telescopic rod 201. At this time, the overlap between motor stator 107 and rotor 108 will change, and speed limiting is achieved by reducing the overlap. If the controller built into the controller frame 106 continuously applies a high alternating current, the overlap between the motor stator 107 and the rotor 108 gradually decreases while the friction balls 206 rub against the gradually widening friction plate 300. The friction balls 206 rotate with the hub 100 while the arc plate 207 remains stationary. As the downward pressure on the friction balls 206 increases, the friction force they experience also increases, thereby limiting the speed of the hub 100. At the same time, the friction force between the friction balls 206 and the gradually widening friction plate 300 generates heat, which is conducted to the lubricant preheating chamber 302 through the heat transfer pipe 303. Then, the lubricant in the lubricant chamber 305 is preheated through the transmission hose 304, so that the lubricant in the bearing 105 reaches the optimal working state. Simultaneously, when the friction ball 206 contacts the gradually widening friction plate 300 and generates friction, vibration will be generated. The vibration force on the friction ball 206 will act on the piston rod 402, causing it to move closer to the compressor housing 401 and squeeze the spring 404. The movement of the piston rod 402 absorbs the vibration generated by the friction ball 206. When the piston rod 402 reciprocates, it will drive the intake check valve 405 to draw in air. After the air is drawn in by the intake check valve 405 into the compressor housing 401, it is squeezed by the piston end of the piston rod 402 and discharged through the exhaust check valve 406. Subsequently, the exhaust check valve 406 is connected to the air supply nozzle 400, and the air is discharged through the air supply nozzle 400. When the hub 100 rotates, it will drive the fan blade 110 to rotate and form an airflow. Under the action of the air supply nozzle 400, the airflow is guided to achieve cooling of the motor stator 107 and rotor 108.

[0043] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0044] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. An energy-saving electric vehicle motor with speed-limiting function, comprising a wheel hub (100), characterized in that, Also includes: Motor assembly and controller frame (106) integrated into the hub (100); The motor assembly includes a motor stator (107) and a rotor (108), and the controller frame (106) is used to drive the motor assembly to operate; A mechanical speed limiter, comprising a displacement component and a friction component; The displacement assembly includes a stator link (200) that allows the motor stator (107) to move within the controller frame (106), and radially movable centrifugal hammers (208) and a preload spring (209) that provides a reset preload force thereon. The centrifugal hammers (208) are driven by centrifugal force to move the stator link (200) when the speed of the hub (100) increases. The friction assembly is linked with the centrifugal hammer ball (208) and is configured to generate frictional resistance with the displacement assembly, and generate frictional heat when the hub (100) overspeeds; A heat recovery system includes a heat transfer pipe (303) and a lubricant chamber (305). The lubricant chamber (305) is used to contain lubricant and receive heat generated by the friction assembly through the heat transfer pipe (303) to preheat the lubricant.

2. The energy-saving electric vehicle motor with speed-limiting function according to claim 1, characterized in that: The friction assembly also includes a ring frame (203) fixedly connected to the stator connecting frame (200) and friction balls (206) rotating with the hub (100). An arc plate (207) is fixedly connected to one side of the ring frame (203), and a gradually widening friction plate (300) is fixedly connected to the surface of the arc plate (207). The friction balls (206) engage with the gradually widening friction plate (300) under the drive of the displacement assembly to generate friction braking force.

3. The energy-saving electric vehicle motor with speed-limiting function according to claim 2, characterized in that: The displacement assembly also includes a crank (204), the two ends of which are connected to centrifugal hammer balls (208) and friction balls (206) respectively, and a bracket (205) for the crank (204) to swing is fixedly connected inside the hub (100).

4. An energy-saving electric vehicle motor with speed-limiting function according to claim 2, characterized in that: The heat energy recovery and utilization system also includes multiple heat-conducting pipes (301) connected to the lubricant preheating chamber (302). The heat-conducting pipes (301) are fixedly connected to the gradually widening friction plate (300). A heat transfer pipe (303) is fixedly connected inside the heat-conducting pipe (301). The first end of the heat transfer pipe (303) is thermally connected to the friction area of ​​the gradually widening friction plate (300), and the second end is thermally connected to the lubricant preheating chamber (302). The lubricant preheating chamber (302) is connected to the lubricant chamber (305) through a transmission hose (304).

5. An energy-saving electric vehicle motor with speed-limiting function according to claim 3, characterized in that: It also includes a shock-absorbing assembly and a cooling assembly. The shock-absorbing assembly includes a compressor housing (401) fixedly connected inside the crank (204) and a piston rod (402) slidably disposed inside the compressor housing (401). The outer surface of the friction ball (206) is provided with a collar (403) for rolling. The end of the piston rod (402) away from the compressor housing (401) is fixedly connected to the collar (403). The compressor housing (401) is fixedly connected with a spring (404) for driving the piston rod (402) to return to its original position.

6. An energy-saving electric vehicle motor with speed-limiting function according to claim 5, characterized in that: The cooling assembly includes an inlet check valve (405) and an outlet check valve (406) respectively connected to both sides of the compressor housing (401). The inlet check valve (405) allows external gas to enter the compressor housing (401), and the outlet check valve (406) allows gas to be discharged from the compressor housing (401). The exhaust end of the outlet check valve (406) is connected to an air supply nozzle (400).

7. An energy-saving electric vehicle motor with speed-limiting function according to claim 1, characterized in that: The inner wall of the hub (100) is fixedly connected to a connecting frame (103), and the inside of the hub (100) is fixedly connected to a rotor frame (104) for supporting the rotor (108). The connecting frame (103) is connected to the main shaft (102) through a bearing (105).

8. An energy-saving electric vehicle motor with speed-limiting function according to claim 1, characterized in that: It also includes a main shaft (102) fixedly connected to the controller frame (106), and the controller frame (106) has a sliding groove for the motor stator (107) to slide inside.

9. An energy-saving electric vehicle motor with speed-limiting function according to claim 1, characterized in that: The controller frame (106) is internally fixedly connected to a telescopic rod (201). The telescopic end of the telescopic rod (201) is fixedly connected to the stator frame (200). The outer surface of the telescopic rod (201) is fitted with a reset spring (202) for driving the telescopic rod (201) to reset.

10. An energy-saving electric vehicle motor with speed-limiting function according to claim 7, characterized in that: The inner wall of the rotor frame (104) is fixedly connected with multiple fan blades (110), the inside of the connecting frame (103) is provided with heat dissipation holes (109), and a brake pad (101) is fixedly connected to one side of the hub (100).

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