TWI572125B - Rotor heat dissipation structure of inner rotor motor - Google Patents

Description

Rotor heat dissipation structure of inner rotor motor

The invention relates to a rotor heat dissipation structure of an inner rotor motor, which mainly relates to a heat dissipation of the inner rotor to improve the heat dissipation efficiency of the motor.

The inner rotor of the inductive motor senses the fluctuating magnetic field of the stator armature winding, and the electric conductor of the inner rotor can cut the magnetic field lines of the stator magnetic field to induce electromotive force and current, and cause the charged electric conductor to generate a rotating motion in the magnetic field.

When the motor is running, heat energy will be generated. The heat energy is transmitted to the motor coil enameled wire, which may cause the enameled wire plastic to melt and cause coil short-circuit damage. Therefore, the current motor often has a heat dissipation design, and for the inner rotor motor, the structure is set in the outer casing of the stator. A rotor is arranged in the stator, and the rotor is connected to the output shaft, and a plurality of fins are arranged outside the casing, so that the heat source is radiated to the stator when the rotor is running, and then transferred to the casing and the atmosphere to dissipate heat.

Although the above design can be dissipated by the airflow of the atmosphere, the heat of the rotor at the center of the motor cannot be directly radiated, and the thermal energy generated by the operation of the rotor is radiated to the stator, which will still cause damage to the outer wall of the polymer coil of the stator coil and cause short circuit of the coil. The motor cannot be lost.

The object of the present invention is to provide an inner rotor of an inner rotor motor that can actively dissipate heat and improve the heat dissipation efficiency and service life of the motor.

The invention comprises a casing, a stator, a rotor and a shaft, and the casing has a receiving space therein, and the heat dissipating fins can be disposed outside; the stator is disposed in the accommodating space of the casing, and has a stator coil and a center a hollow portion; the rotor is disposed in the hollow portion of the stator, and has an air gap between the stator and the stator, and the variable magnetic field of the stator coil can rotate the rotor to generate eddy current; and the outer surface of the shaft is coupled with the rotor and is located in the outer casing. The inner segment and the outer segment protruding from the outer portion of the outer casing are further provided with a hollow portion extending from the inner segment to the outer segment at the center of the shaft, and a heat conducting device is disposed at the hollow portion.

Further, the two ends of the hollow portion of the shaft are closed, and the heat conducting device can be a low boiling point fluid, and the high heat generated by the rotation of the rotor can evaporate the fluid at the inner segment position, and generate a siphon effect to transfer the heat energy to the outer segment, and Cooled by the outside air of the outer casing to form a liquid state, and the liquid-phase two-phase heat exchange can be used to quickly derive the thermal energy of the rotor operation, so that the rotor temperature can be reduced and the thermal energy can be radiated to the stator coil, and the stator coil can be reduced. Enamelled insulation damage to improve motor life.

Further, the heat conducting device may be a heat pipe, and the heat pipe is disposed in the inner portion of the shaft to the hollow portion of the outer portion, so that the outer wall thereof is combined with the inner wall of the hollow portion, and the inner wall of the heat pipe is provided with a capillary porous surface and is disposed in the heat pipe. The boiling point fluid causes the high heat generated by the rotation of the rotor to be transmitted to the inner section of the shaft to evaporate the fluid in the heat pipe, and the vapor is displaced to the corresponding outer section of the heat pipe and then transferred to the outside of the shaft, and is cooled by the external airflow into a liquid, and the liquid The capillary inner surface of the heat pipe can be quickly returned to the corresponding inner segment position, and the rotor air temperature can be reduced by the liquid-phase two-phase rapid heat exchange, and the lacquer insulation damage of the stator coil can be reduced to improve the motor life.

Further, the heat conducting device may be a high heat conductive material, and the high heat conducting material may be copper, aluminum, silver, and is inserted into the hollow portion of the shaft to the hollow portion of the outer portion to be combined with the shaft, so that the high heat generated by the operation of the rotor can be transmitted to The inner section of the shaft is transferred to the high heat conductive material, and the high heat conductive material can quickly transfer the high temperature of the inner section to the corresponding outer section position, and the airflow outside the outer casing is rapidly cooled to reduce the rotor operating temperature.

The design of the invention can make the rotor located in the center of the motor actively dissipate heat, and the heat dissipation efficiency can be far more efficient than that of providing only the heat dissipation fins for the stator to cool down the stator, and the motor can be improved in service life, and the motor of the invention can be improved. It can be applied to electric vehicles or other implements, and it can improve the reliability and life of electric vehicles.

1‧‧‧Shell

11‧‧‧ accommodating space

12‧‧‧ Heat sink fins

2‧‧‧stator

21‧‧‧statar coil

22‧‧‧ Hollow

3‧‧‧Rotor

31‧‧‧ Air gap

4‧‧‧Axis

41‧‧‧Internal section

42‧‧‧External segment

43‧‧‧ Hollow

44‧‧‧heat conduction device

441‧‧‧ fluid

442‧‧‧ heat pipe

443‧‧‧ outer wall

444‧‧‧ inner wall

445‧‧‧ fluid

446‧‧‧High thermal conductivity

5‧‧‧External components

6‧‧‧Heat block

61‧‧‧Heat fins

The first figure is a schematic cross-sectional view of the first embodiment of the present invention corresponding to the motor.

The second drawing is a schematic cross-sectional view of a motor according to a first embodiment of the present invention.

The third figure is a schematic diagram of the heat dissipation of the rotor in the first embodiment of the present invention.

The fourth figure is a schematic cross-sectional view of the second embodiment of the present invention corresponding to the motor.

Fig. 5 is a schematic view showing the heat dissipation of the rotor of the second embodiment of the present invention.

Figure 6 is a schematic cross-sectional view of the third embodiment of the present invention corresponding to the motor.

Referring to the first to third figures, the first embodiment of the present invention includes a casing 1, a stator 2, a rotor 3, and a shaft 4, and the casing 1 has an accommodation space 11 and externally disposed with fins 12; The stator 2 is disposed in the accommodating space 11 of the outer casing 1 and has a stator coil 21 and has a hollow portion 22 at the center; and the rotor 3 is disposed in the hollow portion 22 of the stator 2, and An air gap 31 is provided between the stators 2, and the fluctuating magnetic field of the stator coil 21 causes the rotor 3 to generate eddy current rotation.

The outer surface of the shaft 4 is coupled to the rotor 3 and has an inner section 41 located inside the outer casing 1 and an outer section 42 protruding from the outer portion of the outer casing 1, and the outer section 42 is connected to the outer component 5 and is also centered on the shaft 4 The inner section 41 extends to the outer section 42 to position the hollow portion 43, and the heat conducting device 44 is disposed in the hollow portion 43, and the heat dissipating block 6 is disposed on the outer portion 42 of the shaft 4, and the heat dissipating block 6 has the heat dissipating fins 61.

Moreover, the two ends of the hollow portion 43 of the shaft 4 are closed, and the heat conducting device 44 is a low boiling point fluid 441, such as water, methanol, ethanol, acetone, and the high heat generated by the rotation of the rotor 3 can make the fluid in the inner section 41 position 441. Evaporating and generating a siphon effect to transfer thermal energy to the outer section 42 and being cooled by the outside air of the outer casing 1 to form a liquid state, and the liquid-phase two-phase heat exchange can be used to quickly derive the thermal energy of the rotor 3, so that the temperature of the rotor 3 can be The heat radiation is reduced and reduced to the stator coil 21, and the enamel insulation damage of the stator coil 21 can be reduced to increase the life of the motor.

4 and 5 are a second embodiment of the present invention, and the second embodiment is similar to the first embodiment. The difference is that the heat conducting device 44 is a heat pipe 442, and the heat pipe 442 is placed inside the shaft 4. 41 to the hollow portion 43 of the outer portion 42 such that the outer wall 443 is combined with the inner wall 444 of the hollow portion 43, and the inner wall 444 of the heat pipe 442 is provided with a capillary porous surface, and a low boiling point fluid 445 such as water is disposed in the heat pipe 442. , methanol, ethanol, acetone, so that the high heat generated by the rotation of the rotor 3 can be transmitted to the inner section 41 of the shaft 4 to evaporate the fluid 445 in the heat pipe 442, and the vapor is displaced to the position of the corresponding outer section 42 of the heat pipe 442 and then transmitted to the outside of the shaft 4 And cooled by an external air stream into a liquid, and the liquid can pass through The capillary surface of the inner wall 444 of the heat pipe 442 is quickly returned to the position corresponding to the inner section 41, and the operating temperature of the rotor 3 can be reduced by the liquid-phase two-phase rapid heat exchange, and the enamelled insulation damage of the stator coil 21 can be reduced to improve the motor life. .

Please refer to the sixth embodiment of the third embodiment of the present invention, and the third embodiment is similar to the first embodiment. The difference is that the heat conducting device 44 is a high thermal conductive material 446, and the high thermal conductive material 446 can be copper or aluminum. And silver, and inserted into the hollow portion 43 of the inner portion 41 to the outer portion 42 of the shaft 4 to be combined with the shaft 4, so that the high heat generated by the operation of the rotor 3 can be transmitted to the inner portion 41 of the shaft 4 and then transferred to the high heat conductive material 446, and The high heat conductive material 446 can quickly transfer the high temperature of the inner section 41 to the corresponding outer section 42 position, and the airflow outside the outer casing 1 is rapidly cooled to reduce the operating temperature of the rotor 3.

In addition, the foregoing first to third embodiments of the present invention, in combination with the heat dissipating block 6, can more quickly cool down the heat source transmitted to the outer segment 42 of the shaft 4, thereby improving the heat dissipation efficiency.

The design of the invention can enable the rotor 3 located in the center of the motor to actively dissipate heat, and the heat dissipation efficiency can be far more efficient than that of the heat sink fin 12 for the outer casing 1 to lower the temperature of the stator 2, and the motor can be improved in service life. The motor of the invention can be applied to an electric vehicle or other implements, and can improve the reliability and quality of the electric vehicle type application tool, and the foregoing embodiments are illustrative of the invention, and are not limited by the invention, and are based on the spirit of the present invention. Equivalent changes are also within the scope of the invention.

1‧‧‧Shell

11‧‧‧ accommodating space

12‧‧‧ Heat sink fins

2‧‧‧stator

21‧‧‧statar coil

22‧‧‧ Hollow

3‧‧‧Rotor

31‧‧‧ Air gap

4‧‧‧Axis

41‧‧‧Internal section

42‧‧‧External segment

43‧‧‧ Hollow

44‧‧‧heat conduction device

441‧‧‧ fluid

5‧‧‧External components

6‧‧‧Heat block

61‧‧‧Heat fins

Claims (7)

The rotor heat dissipation structure of the inner rotor motor comprises: a casing having a receiving space therein; a stator disposed in the accommodating space of the casing, having a stator coil and having a hollow portion at the center; and a rotor disposed at the stator An air gap between the hollow portion and the stator; a shaft, the outer surface is coupled with the rotor, and has an inner portion located inside the outer casing and an outer portion protruding from the outer portion of the outer casing, and extending from the inner portion to the outer portion at the center of the shaft The hollow portion is disposed at a position, and the heat conducting device is disposed in the hollow portion; the two ends of the hollow portion of the shaft are closed, and the heat conducting device is a low boiling point fluid. The rotor heat dissipation structure of the inner rotor motor according to claim 1, wherein the low boiling point fluid is water, methanol, ethanol or acetone. The rotor heat dissipating structure of the inner rotor motor according to claim 1, wherein the heat conducting device is a heat pipe, and the heat pipe is disposed in the hollow portion of the inner portion of the shaft to the outer portion, so that the outer wall is combined with the inner wall of the hollow portion. The inner wall of the heat pipe is provided with a capillary porous surface, and a low boiling fluid is disposed in the heat pipe. The rotor heat dissipation structure of the inner rotor motor according to claim 3, wherein the low boiling point fluid is water, methanol, ethanol or acetone. The rotor heat dissipation structure of the inner rotor motor according to claim 1, wherein the heat conducting device is a high heat conductive material. The rotor heat dissipation structure of the inner rotor motor according to claim 5, wherein the high heat conductive material is copper, aluminum or silver, and is inserted into the hollow portion of the inner portion of the shaft to the outer portion to be combined with the shaft. The rotor heat dissipation structure of the inner rotor motor according to any one of claims 1 to 6, wherein the outer section of the shaft is provided with a heat dissipation block, and the heat dissipation block has heat dissipation fins.