Direct current drive motor

A direct current drive motor with a stator core, an end insulator, and a coil winding forming a stator, and a housing, a magnetic yoke shell, and multiple magnetic tiles, forming a rotor. The magnetic yoke shell and the magnetic tiles are disposed on the housing. Multiple teeth protrude from a side wall of the stator core. A slot is formed between two adjacent teeth. The coil winding is disposed in the slot and wraps around the tooth.

CROSS-REFERENCE TO RELATED APPLICATIONS

Pursuant to 35 U.S.C. §119 and the Paris Convention Treaty, this application claims the benefit of Chinese Patent Application No. 200810220110.3 filed on Dec. 3, 2008, the contents of which are incorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to a direct current drive motor.

2. Description of the Related Art

Nowadays, direct current drive motors (DC motors) are widely used. Components of DC motors include a rotor with a housing, a magnetic yoke shell, and multiple magnetic tiles, along with a stator with a stator core, an end insulator, and coil windings. However, conventional designs of DC motors presents many problems, such as, e.g., (a) large disparity between the number of stator slots and magnets on the rotor results in high cogging torque, excessive vibrations, and reduced life span of the motor; (b) high rigidity and limited buffering capacity of the rotor housing, which is usually made of metal, does not allow for absorbing vibrations of the motor; (c) inadequate directionality of winding wires, which are usually wrapped in a clockwise or counterclockwise direction around each tooth and between two adjacent teeth, results in a high cogging torque and high vibrations; d) overlap between transition lines makes it difficult to produce wire windings; and (e) the magnetic induction device is difficult t to install, and the induction signal is poor.

SUMMARY OF THE INVENTION

In view of the above-described problems, it is one objective of the invention to provide a direct current drive motor that features reduced vibration, stable operation, convenient installation, and long working life.

To achieve the above objective, in accordance with one aspect of the present invention, there is provided a direct current drive motor, comprising a stator comprising a stator core, an end insulator and a coil winding, and a rotor comprising a housing, a magnetic yoke shell and multiple magnetic tiles, wherein the magnetic yoke shell and the magnetic tiles are disposed on the housing, multiple teeth protrude from a side wall of the stator core, a slot is formed between two adjacent teeth, and the coil winding is disposed in the slot and wraps around the tooth.

In certain classes of this embodiment, the number of the slots is 36.

In certain classes of this embodiment, the slots are uniformly distributed in a circumferential direction, and an area thereof is the same.

In certain classes of this embodiment, the number of the magnetic tiles is 42, and thus 42 poles are formed.

In certain classes of this embodiment, the motor further comprises a magnetic induction device.

In certain classes of this embodiment, the magnetic induction device comprises a fixed mount, a PCB board, a Hall component, a connector, and a capacitor.

In certain classes of this embodiment, the PCB board is disposed on the fixed mount, the Hall component, the connector, and the capacitor are disposed on the PCB board, and the fixed mount is fixedly disposed on the end insulator.

In certain classes of this embodiment, the housing comprises a side wall, an end cover, a cavity, an opening, a base, and a central hole.

In certain classes of this embodiment, the housing is integrally formed by injection molding, the end cover is disposed at the bottom of the side wall, the cavity is formed between the side wall and the end cover, the opening is disposed at the top of the housing, the base is disposed at the center of the end cover, and the central hole is disposed at the center of the base and connected to a transmission shaft.

In certain classes of this embodiment, the central hole and the base are integrally formed by injection molding.

In certain classes of this embodiment, the motor further comprises a rotating spline connected to the base.

In certain classes of this embodiment, the central hole is disposed in the rotating spline.

In certain classes of this embodiment, the motor further comprises a rotating spline disposed in the base.

In certain classes of this embodiment, the central hole is disposed in the rotating spline.

In certain classes of this embodiment, the base is connected to the side wall via multiple wind wheels, and an air inlet is disposed between adjacent wind wheels.

In certain classes of this embodiment, the magnetic yoke shell and the magnetic tiles are disposed on the inner portion of the side wall.

In certain classes of this embodiment, the magnetic yoke shell, the magnetic tiles can also be integrally formed with the housing and disposed in the side wall.

In certain classes of this embodiment, the coil windings comprise multiple in-phase windings and anti-phase windings, the winding wires of the in-phase windings are firstly wrapped around two adjacent teeth and then cross four teeth, winding directions of the two adjacent teeth of the in-phase windings are opposite, and winding directions of adjacent teeth of the anti-phase windings are the same.

In certain classes of this embodiment, multiple cylinders are disposed on the end insulator, multiple protruding portions are disposed at the bottom of the cylinder and between adjacent cylinders, a transition line between two adjacent teeth is hang on the cylinder and supported by the top of the protruding portion, and the protruding portions have different height.

Advantages of the invention include the following:

1) 36 slots are disposed on the stator core, and 42 poles are formed on the rotor, and thus cogging torque is relatively low and the motor vibrates only slightly and generates little noise, which greatly increases working life of the motor;

2) the housing of the rotor is formed by injection molding, and thus has relatively small rigidity and large buffer capacity to absorb vibration from the motor;

3) the winding wires of the in-phase windings are first wrapped around two adjacent teeth and then run across the next four teeth, the winding directions at the two adjacent teeth of the in-phase windings are opposite, and the winding directions at the adjacent teeth of the anti-phase windings are the same, which causes low cogging torque and prevents vibrations;

4) the protruding portions have different height, thus transition lines do not overlap with each other which makes it easier to produce wire windings;

5) the magnetic induction device is easy for installation and location, and the induction signal is relatively good.

DETAILED DESCRIPTION OF THE EMBODIMENTS

As shown inFIGS. 1,2and6, a direct current drive motor of the invention comprises a rotor1, a stator2, and a magnetic induction device3. The rotor1is disposed outside the stator2. The stator2comprises a stator core21, an end insulator23, and a coil winding22. The rotor1comprises a housing11, a magnetic yoke shell12, and multiple magnetic tiles13.

36 slots212are disposed on the stator core21. Multiple pins24protrude from inner wall of the stator core21. The number of the magnetic tiles13is 42, and thus 42 poles are formed.

The slots212are uniformly distributed in a circumferential direction, and their size is equal.

The magnetic induction device3comprises a fixed mount31, a PCB board, a Hall component, a connector, and a capacitor. The PCB board is disposed on the fixed mount31, the Hall component, the connector, and the capacitor are disposed on the PCB board, and the fixed mount31is fixedly disposed on the end insulator23.

The coil winding22is made of enameled aluminum wire or enameled copper wire.

As shown inFIGS. 3 and 4, the housing11of a first embodiment of the invention is integrally formed by injection molding, and comprises a side wall111and an end cover112disposed at the bottom of the side wall111. A cavity is formed between the side wall111and the end cover112. An opening is disposed at the top of the housing11. A base113is disposed at the center of the end cover112. A central hole14is disposed at the center of the base113and connected to a transmission shaft. The magnetic yoke shell12and the magnetic tiles13are disposed on inner wall of the side wall111.

As shown inFIG. 5, the housing11of the second embodiment of the invention is integrally formed by injection molding with the magnetic yoke shell12and the magnetic tiles13. The magnetic yoke shell12and the magnetic tiles13are received in the side wall111.

The central hole14and the base113are integrally formed by injection molding. In another embodiment, a rotating spline is connected to the base113, and the central hole14is disposed in the rotating spline. In a further embodiment, the rotating spline is disposed in the base113, and the central hole14is disposed in the rotating spline.

The base113is connected to the side wall111via multiple wind wheels114, and an air inlet115is disposed between adjacent wind wheels114.

As shown inFIGS. 6 and 7, multiple teeth211protrude from a side wall of the stator core21, and a slot212is formed between two adjacent teeth211. The coil winding22is disposed in the slot212and wraps around the tooth211. The coil winding22comprises multiple in-phase windings and anti-phase windings. The winding wires of the in-phase windings are firstly wrapped around two adjacent teeth211and then cross four teeth211thereof, winding directions of the two adjacent teeth211of the in-phase windings are opposite, and winding directions of adjacent teeth211of the anti-phase windings are the same.

InFIG. 7, the coil winding22comprises a U phase, a V phase and a W phase. Both ends of the U-phase winding are labeled A and X, both ends of the V-phase winding are labeled B and Y, and both ends of the W-phase winding are labeled C and Z. The U-phase winding wraps around the 1st, the 2nd, the 7th, the 8th, the 13th, the 14th, the 19th, the 20th, the 25th, the 26th, the 31th and the 32th teeth. The V-phase winding wraps around the 3rd, the 4th, the 9th, the 10th, the 15th, the 16th, the 21th, the 22th, the 27th, the 28th, the 33th and the 34thteeth. The W-phase winding wraps around the 5th, the 6th, the 11th, the 12th, the 17th, the 18th, the 23th, the 24th, the 29th, the 30th, the 35thand the 36thteeth.

As shown inFIGS. 8 and 9, multiple cylinders231are disposed on the end insulator23. Multiple protruding portions232are disposed at the bottom of the cylinder231and between adjacent cylinders231. A transition line between two adjacent teeth211is hang on the cylinder231and supported by the top of the protruding portion232. The protruding portions232have different height, so that transition lines of the coil windings22with different phases are not connected to each other in space.