TWI676339B - electric motor - Google Patents

Abstract

A motor includes a bottom case having a plurality of air guide grooves, a case cover disposed on the bottom case and jointly defining a pivot space with the air guide grooves, and a rotatable cover. A rotor disposed in the pivot space, a stator disposed in the pivot space and surrounding the rotor, and a shell cover which is disposed on the bottom case and covers the shell cover. The rotor has a plurality of openings penetrating from the top surface to the bottom surface. When the rotor rotates relative to the stator, airflow can be introduced by the air guide grooves to form active convective heat dissipation to improve heat dissipation efficiency, and the design of the air guide grooves can prevent eddy currents from forming on the bottom case. Therefore, it is possible to avoid heating or failure due to eddy current.

Description

electric motor

The present invention relates to a motor, and more particularly to a motor having an active heat dissipation function.

Referring to FIG. 1, a general electric motor 1 includes a casing 11, a stator 12 fixedly disposed in the casing 11, and a rotor rotatably disposed in the casing 11 and surrounded by the stator 12 along its own axis. 13. The rotor 13 can rotate relative to the stator 12 under the influence of magnetic force, thereby generating power to drive other structures or components. Since the rotor 13 generates high heat when rotating with respect to the stator 12, a plurality of ventilation holes 111 are opened in the casing 11 so that airflow can enter the casing 11 to cool the stator 12 and the rotor. 13. However, the ventilation hole 111 of the motor 1 can only be passively entered by external air flow to generate convection heat dissipation, which lacks the function of active heat dissipation. In addition, the aforementioned casing 11 is a one-piece design and is made of metal, and the inner surface faces the rotor 13. Because the conductor generates eddy current in a constantly changing magnetic field, The inner surface is induced to generate electricity by the changing magnetic field of the rotor 13, which generates eddy currents on the casing 11. Excessive eddy currents can cause overheating and retard the rotation of the rotor 13.

Therefore, an object of the present invention is to provide an electric motor with an active heat dissipation function and avoiding eddy currents from being generated in the housing.

Therefore, the electric motor of the present invention includes a bottom case having a plurality of air guiding grooves extending from the top surface to the bottom surface, and a bottom casing provided on the bottom case and jointly defining a communication with the air guiding grooves. A shell cover of the pivot space, a rotor rotatably disposed in the pivot space, a stator disposed in the pivot space and surrounding the rotor, and a cover disposed on the bottom case and covering the rotor Shell cover of the shell cover. The rotor has a plurality of openings penetrating from the top surface to the bottom surface.

The effect of the present invention is that the rotors are provided with a plurality of openings, so when the rotor rotates relative to the stator, the air in the openings will be forced to flow due to rotation, thereby generating an active suction effect. In this way, the airflow can be introduced by the air guide grooves, and the air below can be drawn upward through the openings, then passed down through the gap on the stator, and finally sent out by the air guide grooves, so that an active type can be formed. Convection cooling to improve cooling efficiency. In addition, the air guide grooves are disposed below the rotor, so the area of the bottom case affected by the magnetic field of the rotor can be reduced, and the bottom case is cut by the air guide grooves instead of a complete plane. The induced current is not easy to be generated thereon, so the generation of eddy current can be avoided.

Referring to FIG. 2, FIG. 3, and FIG. 4, an embodiment of the electric motor 2 according to the present invention includes a bottom case 21, and a pivot space provided on the bottom case 21 and defining a pivot space together with the bottom case 21. A housing cover 22 of 220, a rotor 23 rotatably disposed in the pivot space 220, a stator 24 provided in the pivot space 220 and surrounding the rotor 23, and a cover provided on the bottom case 21 A cover 25 covering the cover 22 is placed on the cover.

Referring to FIG. 2, FIG. 4, and FIG. 5, it should be particularly noted that, for the convenience of describing the appearance of the cover 22, the cover 25 is omitted in FIG. 5. The bottom case 21 has a bottom wall portion 211 that carries the rotor 23 and the stator 24, and a surrounding wall portion 212 that connects the outer periphery of the bottom wall portion 211 and surrounds the stator 24. The bottom wall portion 211 has a plurality of air guiding grooves 213 extending from the top surface to the bottom surface and communicating with the pivot space 220. In addition to providing a hole 221 for the rotor 23 to pass through, the casing cover 22 does not completely cover the rotor 23 and the stator 24 as shown in FIG. 5, so the pivoting space 220 is not closed. The top surface of 22 is in contact with the inner wall surface of the casing 25, and the casing cover 22 is not completely round and has a notch, and the casing cover 22 is made of copper and can be used to electrically connect a plurality of electronic components provided at the notches. 3. The heat generated during the operation of the electronic components 3 can be transferred to the cover 22 through contact conduction to achieve the effect of heat dissipation. The rotor 23 has a plurality of openings 231 penetrating from the top surface to the bottom surface and arranged annularly at equal angles to each other. The casing 25 has a joint portion 251 which is locked to the top edge of the bottom case 21 around the wall portion 212, and an outer portion which is annularly disposed on the joint portion 251 and forms two through openings 252 on the outer peripheral surface. The ring wall portion 253 and a top wall portion 254 connected to the top edge of the outer ring wall portion 253 and spaced apart from the bottom wall portion 211 of the bottom case 21. The through openings 252 are used for conducting wires to electrically connect the electronic components 3 on the cover 22.

Referring to FIG. 2, FIG. 5, and FIG. 6, when the rotor 23 rotates relative to the stator 24, the air in the openings 231 will flow due to the rotation, and the air guide grooves 213 communicating with the outside are provided in At the lower part, the outside air will be driven to enter the pivoting space 220 from the air guiding grooves 213 and flow upward to the cover 22 through the openings 231, and then along the bottom surface of the cover 22 The flowing air will pass downward through the gap on the stator 24, and finally flow from the air guide grooves 213 at the bottom to the outside again to achieve the effect of actively drawing airflow to generate convection heat dissipation. Since the case cover 22 is made of copper, it can absorb the heat in the flowing air in contact with it through the bottom surface, and can also absorb the heat on the electronic components 3 through contact conduction, and contact the cover 25 through the top surface. The inner wall surface of the top wall portion 254 is used to conduct heat to the casing 25 to dissipate thermal energy from the casing 25 to the outside and enhance the heat dissipation effect.

In addition, the air guide grooves 213 are located directly below the rotor 23, so the contact area between the top surface of the bottom wall portion 211 and the magnetic field generated by the rotor 23 is small, and the air guide grooves 213 make the bottom The wall portion 211 is not a complete plane, and the induced current is not easy to be generated thereon, so that the generation of eddy current can be avoided to avoid heat generation and other related problems.

In summary, when the rotor 23 rotates relative to the stator 24, airflow can be introduced from the outside to actively cool the rotor 23 and the stator 24, and the design of the air guide grooves 213 can avoid the bottom case 21 generates eddy current, so it can indeed achieve the purpose of the invention.

However, the above are only examples of the present invention. When the scope of implementation of the present invention cannot be limited in this way, any simple equivalent changes and modifications made in accordance with the scope of the patent application and the content of the patent specification of the present invention are still Within the scope of the invention patent.

2 ······ Electric motor 21 ···· Bottom case 211 ·· Bottom wall part 212 ·········· Surrounding the wall part 213 ... ···· Housing cover 220 ···· Pivoting space 221 ··· 23 Holes ···· Rotor 231 ···· 24 ···· 25 ······························································ element

Other features and effects of the present invention will be clearly presented in the embodiment with reference to the drawings, in which: FIG. 1 is a schematic diagram illustrating a general electric motor; FIG. 2 is an exploded perspective view illustrating one of the electric motors of the present invention Embodiment; Fig. 3 is a perspective view illustrating the assembly relationship of the components after the assembly of the embodiment; Fig. 4 is a cross-sectional view illustrating the cross-sectional aspect of the embodiment; Fig. 5 is a top view illustrating the embodiment, omitting a cover A plan view from the rear; and FIG. 6 is a schematic diagram illustrating a path of air flow in this embodiment.

Claims (4)

An electric motor includes: a bottom case having a plurality of air guide grooves extending from a top surface to a bottom surface; a case cover provided on the bottom case and jointly defining the air guide grooves with the bottom case. A pivot space; a rotor rotatably disposed in the pivot space and above the air guide grooves, the rotor has a plurality of openings penetrating from the top surface to the bottom surface; a stator is provided at the pivot The rotor is in the rotating space and surrounds the rotor; and a shell cover is arranged on the bottom shell and covers the shell cover. The motor according to claim 1, wherein the housing has a joint portion coupled to the bottom case, an outer ring wall portion ring-shaped on the joint portion and forming at least one port, and a connection to the The top wall portion of the top edge of the outer ring wall portion. The electric motor according to claim 2, wherein the bottom case has a bottom wall portion forming the air guide grooves, and a surrounding wall portion connected to the bottom wall portion and surrounding the stator. The motor according to claim 1, wherein the case cover is made of copper and a top surface thereof contacts an inner wall surface of the case cover.