Heat dissipation structure for hub motor

Abstract

The invention discloses a heat dissipation structure for a hub motor, the hub motor comprises a mandrel, a mandrel shaft is arranged in the hub motor in a penetrating manner and protrudes out of the hub motor, the mandrel comprises an accommodating part, and the heat dissipation structure for the hub motor comprises a heat pipe and a heat dissipation unit. Wherein the heat pipe is arranged in the accommodating part. The heat dissipation unit is coupled to the mandrel. By means of the heat pipe and the heat dissipation unit, heat energy generated by operation of the hub motor is conducted to the outside, so that the temperature in the hub motor does not exceed the demagnetization temperature, the magnetic force (magnetism) of the stator is kept, and the due working efficiency of the hub motor is kept.

Description

Technical Field

[0001] The present invention is a heat dissipation structure for a wheel hub motor, and in particular refers to a heat dissipation structure capable of reducing the internal temperature of a wheel hub motor in operation so that the internal temperature of the wheel hub motor does not exceed a demagnetization temperature. Background Art

[0002] Existing electric-assisted bicycles (also referred to as electric bicycles) need to rely on the drive of a wheel hub motor to enable the electric-assisted bicycle to travel on the road. Therefore, the wheel hub motor is one of the indispensable and important parts for the electric-assisted bicycle.

[0003] A conventional wheel hub motor includes a housing, a circuit board, a speed measuring Hall sensor, a stator, a rotor, a clutch and a spindle. The circuit board, the speed measuring Hall sensor, the stator, the rotor and the clutch are arranged inside the housing. The spindle passes through the rotor and protrudes outside the housing.

[0004] The stator is made of a neodymium iron boron alloy. When the temperature of this alloy exceeds 100°C, the stator will demagnetize. The demagnetized stator will reduce the repulsive action between the stator and the rotor, thus affecting the performance of the hub motor.

[0005] In actual use, the hub motor will generate heat energy during operation, causing the temperature inside the hub motor to exceed 100°C (demagnetization temperature). As a result, the stator made of NdFeB alloy will be demagnetized, which in turn affects the repulsive action between the stator and the rotor, and further reduces the performance of the hub motor.

[0006] In summary, how to provide a method for solving the demagnetization problem of hub motors caused by temperature is a technical problem that urgently needs to be solved in the field. Summary of the invention

[0007] In view of the above-mentioned shortcomings of the prior art, the applicant has successfully developed the heat dissipation structure for the hub motor of the present invention after years of research and experimentation.

[0008] The invention discloses a heat dissipation structure for a wheel hub motor. The wheel hub motor includes a spindle, which is inserted into the wheel hub motor and protrudes from the outside of the wheel hub motor. The spindle includes a receiving portion. The heat dissipation structure for the wheel hub motor includes a heat pipe and a heat dissipation unit. The heat pipe is arranged in the receiving portion. The heat dissipation unit is coupled to the spindle.

[0009] In one embodiment, the heat dissipation unit is a heat dissipation fin set or a heat dissipation block.

[0010] In one embodiment, the heat dissipation fin assembly includes a disk body and a plurality of heat dissipation fins, and the heat dissipation fins are disposed on one side of the disk body.

[0011] In one embodiment, the accommodating portion is a accommodating groove or a accommodating hole.

[0012] In one embodiment, the accommodating portion and the heat pipe are tightly matched.

[0013] Therefore, the heat dissipation structure for the hub motor of the present invention as described above utilizes the phase change of the working fluid of the heat pipe to conduct the heat energy generated by the operation of the hub motor to the outside, so that the temperature inside the hub motor will not exceed the demagnetization temperature, and the magnetic force (magnetism) of the stator can be maintained, so the working efficiency of the hub motor can be maintained. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a three-dimensional appearance schematic diagram of a heat dissipation structure for a hub motor of the present invention;

[0015] Figure 2 It is a three-dimensional exploded schematic diagram of a heat dissipation structure for a hub motor of the present invention;

[0016] Figure 3 The figure is a cross-sectional schematic diagram of a heat dissipation structure for a hub motor according to the present invention.

[0017] Among them: 10 - wheel hub motor, 11 - spindle, 110 - accommodating portion, 20 - heat pipe, 21 - heat dissipation unit, 210 - disk, 211 - heat dissipation fins. DETAILED DESCRIPTION

[0018] In order to enable a person having ordinary knowledge in the technical field to fully understand the technical features, contents and advantages of the present invention and the effects that can be achieved, the present invention is hereby described in detail as follows in conjunction with drawings and in the form of embodiments. The drawings used therein are only for illustration and auxiliary description, and may not be the actual proportions and precise configurations after the implementation of the present invention. Therefore, the proportions and configurations of the attached drawings should not be interpreted or limited to the scope of rights of the present invention in actual implementation. This should be made clear in advance.

[0019] See also Figure 1 , a three-dimensional schematic diagram of the heat dissipation structure for a hub motor of the present invention. Figure 2 , a three-dimensional exploded schematic diagram of a heat dissipation structure for a hub motor of the present invention. As shown in the figure, the spindle 11 of the hub motor 10 includes a receiving portion 110. The receiving portion 110 can be a receiving hole or a receiving groove.

[0020] See also Figure 3, a cross-sectional schematic diagram of a heat dissipation structure for a hub motor of the present invention. As shown in the figure, the heat dissipation structure includes a heat pipe 20 and a heat dissipation unit 21. The heat pipe 20 is disposed in the accommodating portion 110 and protrudes from the outside of the accommodating portion 110. The heat pipe 20 and the accommodating portion 110 are tightly matched so that the heat pipe 20 is fixed in the accommodating portion 110. The heat dissipation unit 21 includes a disk body 210 and a plurality of heat dissipation fins 211. The heat dissipation fins 211 are disposed on one side of the disk body 210. The disk body 210 is coupled to the free end of the spindle 11.

[0021] In one embodiment, the heat dissipation unit 21 can be a heat dissipation metal block or a heat dissipation fin set. The heat dissipation fin set is the heat dissipation unit 21 as described above.

[0022] In actual use, after the hub motor 10 generates heat energy due to operation, the heat energy will be absorbed by the working fluid inside the heat pipe 20 in the hub motor 10, causing the working fluid to change from liquid to vapor. The vaporized working fluid moves toward the heat dissipation unit 21.

[0023] When the vapor working liquid moves to one end of the heat pipe 20 located at the heat dissipation unit 21, the vapor working liquid conducts the previously absorbed temperature to the heat dissipation unit 21. The heat dissipation unit 21 dissipates the temperature absorbed by the working liquid to the outside. Therefore, the vapor working liquid returns to the liquid working liquid, and the liquid working liquid flows back to the end of the heat pipe 20 located at the hub motor 10 through capillary phenomena, gravity, pressure or pipelines.

[0024] To further discuss, when the vaporous working liquid moves toward one end of the heat pipe 20 located at the heat dissipation unit 21, the thermal energy of the vaporous working liquid will be dissipated to the outside through the outer wall of the core shaft 11, and when the vaporous working liquid moves to one end of the heat pipe 20 located at the heat dissipation unit 21, the thermal energy is also conducted to the heat dissipation unit 21 through the outer wall of the core shaft 11, and then the heat dissipation unit 21 dissipates the thermal energy to the outside.

[0025] As described above, the present invention utilizes the change of the working fluid in the heat pipe 20 between the vapor state and the liquid state, and the heat dissipation unit 21 dissipates the heat energy to the outside, so that 70% to 90% of the heat energy generated by the operation of the hub motor 10 is dissipated to the outside of the hub motor 10, and the temperature inside the hub motor 10 does not exceed the demagnetization temperature. Therefore, the magnetic force (magnetism) of the stator is maintained, so the working efficiency of the hub motor 10 is maintained.

[0026] In summary, the heat dissipation structure for the hub motor 10 of the present invention utilizes the phase change of the working fluid of the heat pipe 20 to conduct the heat energy generated by the operation of the hub motor 10 to the outside, so that the temperature inside the hub motor 10 will not exceed the demagnetization temperature, and the magnetic force (magnetism) of the stator can be maintained, so the working efficiency of the hub motor 10 can be maintained.

[0027] The above description is only for illustrative purposes, and is used to illustrate the feasible specific embodiments of the technical content of the present invention, rather than to limit the present invention. Equivalent substitutions, modifications or changes made by those with ordinary knowledge in the technical field to which the present invention belongs based on the teachings of the contents disclosed in the specification are all included in the scope of the patent application of the present invention and do not depart from the scope of the rights of the present invention.

Claims

1. A heat dissipation structure for a hub motor, characterized in that: The wheel hub motor includes a spindle, the spindle is inserted into the wheel hub motor and protrudes from the outside of the wheel hub motor, the spindle includes a receiving portion, and the heat dissipation structure for the wheel hub motor includes: A heat pipe is arranged in the accommodating portion; and a heat dissipation unit is coupled to the spindle.

2. The heat dissipation structure for a hub motor according to claim 1, characterized in that: The heat dissipation unit is a heat dissipation fin group or a heat dissipation block.

3. The heat dissipation structure for a hub motor according to claim 2, characterized in that: The heat dissipation fin group includes a plate body and a plurality of heat dissipation fins, and the heat dissipation fins are arranged on one side of the plate body.

4. The heat dissipation structure for a hub motor according to claim 1, characterized in that: The accommodating portion is a accommodating groove or an accommodating hole.

5. The heat dissipation structure for a hub motor according to claim 1, characterized in that: The accommodating portion and the heat pipe are tightly matched.

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