CN214674599U

CN214674599U - Special-shaped magnetic shoe of EC outer rotor DC brushless motor

Info

Publication number: CN214674599U
Application number: CN202121126214.5U
Authority: CN
Inventors: 林金强
Original assignee: Guangdong Zhaoqing Deton Co ltd
Current assignee: Guangdong Zhaoqing Deton Co ltd
Priority date: 2021-05-25
Filing date: 2021-05-25
Publication date: 2021-11-09
Anticipated expiration: 2031-05-25

Abstract

An EC outer rotor DC brushless motor special-shaped magnetic shoe relates to the technical field of magnetic shoes on EC outer rotor DC brushless motors. The problem of current EC external rotor DC brushless motor operation in-process, there is the electromagnetic noise that the back electromotive force distortion caused, it is not enough to influence the technique that customer's use was experienced, the centre of a circle of extrados is located DC brushless motor's pivot central line, the radius of intrados is greater than the radius of extrados, the centre of a circle of intrados is towards keeping away from the pivot central line 10mm of DC brushless motor of magnetic shoe body orientation, it is thick in the middle of the formation magnetic shoe body, the special-shaped structure of both sides attenuate gradually. The trend of a magnetic circuit is changed by changing the shape of the inner diameter of the rotor magnetic shoe, so that the back electromotive force of the motor stator winding tends to or approaches to a sine wave, the distortion of the back electromotive force is reduced, and the technical problem of the electromagnetic noise of the motor is solved.

Description

Special-shaped magnetic shoe of EC outer rotor DC brushless motor

Technical Field

The utility model relates to magnetic shoe technical field on EC external rotor DC brushless motor.

Background

The motor in the present new trend system is divided into AC external rotor motor, DC brushless external rotor motor to and EC external rotor DC brushless motor, wherein the cooperation of the stator slot number and the rotor pole number that DC or EC DC brushless external rotor motor generally adopted on the market now is: 1. stator 6 slots, rotor 4 poles; 2. stator 9 slots, rotor 6 poles. The slot poles of the two stator and rotor are matched, the waveform of the back electromotive force generated by the stator winding is distorted, namely, the waveform is not close to a sine wave, so that when the fan runs, the motor generates electromagnetic sound, and the use experience of customers is influenced.

SUMMERY OF THE UTILITY MODEL

To sum up, the utility model discloses an in solving current EC external rotor DC brushless motor operation process, there is the electromagnetic noise that back electromotive force distortion caused, and the technique that the use that influences the customer is experienced is not enough, and provides the special-shaped magnetic shoe on the EC external rotor DC brushless motor.

For solving the technical problem provided by the utility model, adopt technical scheme to be:

the EC outer rotor DC brushless motor special-shaped magnetic shoe comprises a magnetic shoe body, wherein the magnetic shoe body comprises an outer arc surface, an inner arc surface, a left side surface, a right side surface, an upper end surface and a lower end surface; the centre of a circle of cambered surface be located DC brushless motor's pivot central line, the radius of intrados is greater than the radius of extrados, the centre of a circle of intrados is towards keeping away from 10mm of magnetic shoe body direction skew DC brushless motor's pivot central line, forms the magnetic shoe body middle thickness, the special-shaped structure of both sides attenuate gradually.

As to the technical scheme of the utility model for further limiting includes: the radius of the inner arc surface is 38.3 +/-0.1 mm, the size of the outer arc surface is R34.1 +/-0.1 mm, and the central angle radian of the outer arc surface is larger than 59 degrees and smaller than 60 degrees.

The inner arc surface and the corners of the left side surface and the right side surface are chamfer structures of 1mm x45 degrees.

The distance between the upper end surface and the lower end surface is as follows: 42 + -0.1 mm.

The utility model has the advantages that: the utility model discloses a shape that changes the internal diameter of rotor magnetic shoe changes the trend of magnetic circuit, makes the back electromotive force of motor stator winding tend to or be close the sine wave, reduces the distortion of back electromotive force to improve the technical problem of the electromagnetic noise that causes because of the back electromotive force distortion of motor.

Drawings

FIG. 1 is a schematic view of the magnetic shoe of the present invention;

FIG. 2 is a schematic view of the magnetic shoe of the present invention;

FIG. 3 is a schematic view of the magnetic shoe structure of the present invention;

fig. 4 is a schematic structural view of the fan motor with circular pipeline according to the present invention;

FIG. 5 is an exploded view of FIG. 4;

FIG. 6 is a waveform diagram of the back electromotive force of the magnetic shoe of the present invention, the existing magnetic shoe and the stator winding;

FIG. 7 shows the magnetic shoe and the magnetic line of the stator winding of the prior art;

fig. 8 shows the magnetic shoe and the magnetic line of force of the stator winding of the present invention.

Detailed Description

The structure of the present invention will be further described with reference to the accompanying drawings and preferred embodiments of the present invention.

Referring to fig. 1 to 3, the EC outer rotor dc brushless motor special-shaped magnetic shoe of the present invention comprises a magnetic shoe body 1, wherein the magnetic shoe body 1 comprises an outer arc surface 11, an inner arc surface 12, a left side surface 13, a right side surface 14, an upper end surface 15, and a lower end surface 16; the centre of a circle of the extrados 11 and the intrados 12 of current structure is located the central line of DC brushless motor's pivot 2, and the utility model discloses only the centre of a circle of extrados 11 be located the central line of DC brushless motor's pivot 2, and the radius of intrados 12 is greater than the radius of extrados 11, the distance an of the central line of the 1 skew DC brushless motor's of direction pivot 2 of magnetic shoe body is kept away from towards the centre of a circle of intrados 12 is 10mm, forms magnetic shoe body 1 middle thick, the odd-shaped structure of both sides attenuate gradually.

Specific parameters of the magnetic shoe body 1 may be: intrados radius dimension R1 be 38.3 +/-0.1 mm, extrados radius dimension R2 is R34.1 +/-0.1 mm, extrados central angle radian b is for being greater than 59, is less than 60, also can guarantee the application in-process, 6 the utility model discloses in rotor housing 3 can be packed into to magnetic shoe body 1. The inner arc surface 12, the left side surface 13 and the right side surface 14 are all chamfer structures 121 with the angle of 1mm x45 degrees. The specific size of the distance between the upper end face 15 and the lower end face 16 can be as follows: 42 + -0.1 mm.

Referring to fig. 4 and 5, the EC external rotor DC brushless motor includes two major parts, i.e., a built-in control board 4 and a motor body, the control board 4 rectifies an externally input single-phase ac 220V/50Hz or 60Hz power supply into DC310V DC, and then a single chip microcomputer on the control board 4 controls the on/off of 3 sets of MOS transistors to commutate the DC brushless external rotor motor, thereby driving the motor to operate, and the control board 4 is controlled by a field-oriented control (FOC) magnetic field guidance, so that the output torque of the motor is relatively stable.

The control panel 4 is arranged in the controller rear end cover 26; the motor body comprises a motor base 5, the motor base 5 is fixedly installed and connected with a 9-slot stator core 7, an upper framework 8 and a lower framework 9 are arranged at two ends of the slot stator core 7, a winding 20 wound on the upper framework 8 and the lower framework 9 is arranged, and the motor base 5 is insulated and isolated from the control panel 4 through a controller insulation plate 25; motor base 5, stator core 7, go up skeleton 8, lower skeleton 9 and winding 20 constitution motor stator, motor stator rotates through two bearings 22 and connects pivot 2, and two outsides that lie in two bearings 22 in the pivot 2 are equipped with internal tooth conical spring packing ring 23 and axial split washer 24 respectively, 2 fixedly connected with rotor housing 3 in the pivot, 6 the utility model discloses in rotor housing 3 was located to magnetic shoe body 1, 6 utmost point rotors formed.

Because the utility model discloses magnetic shoe body 1 is special-shaped magnetic shoe to change the magnetic line of force trend of two adjacent N, S utmost point magnetic shoes, reduce the back electromotive force distortion volume of the tooth's socket torque of motor and stator winding, make the back electromotive force wave form be close the sine wave, thereby improved the electromagnetic noise of motor, the effect is shown in seeing in figure 6 around improving. Magnetic shoe and stator winding improve the front and back magnetic line of force change see figure 7 and figure 8 magnetic line of force trend route, it is visible the utility model discloses the back electromotive force who makes motor stator winding tends to or is close the sine wave, reduces back electromotive force's distortion to improve the technical problem of the electromagnetic noise that causes because of back electromotive force distortion of motor.

Claims

The EC outer rotor DC brushless motor special-shaped magnetic shoe comprises a magnetic shoe body, wherein the magnetic shoe body comprises an outer arc surface, an inner arc surface, a left side surface, a right side surface, an upper end surface and a lower end surface; the centre of a circle of extrados be located DC brushless motor's pivot central line, its characterized in that: the radius of the inner arc surface is larger than that of the outer arc surface, the circle center of the inner arc surface deviates 10mm from the central line of the rotating shaft of the direct current brushless motor towards the direction far away from the magnetic shoe body, and a special-shaped structure with thick middle and gradually thinned two sides of the magnetic shoe body is formed.
2. The EC outer rotor DC brushless motor special-shaped magnetic shoe of claim 1, wherein: the radius of the inner arc surface is 38.3 +/-0.1 mm, the size of the outer arc surface is R34.1 +/-0.1 mm, and the central angle radian of the outer arc surface is larger than 59 degrees and smaller than 60 degrees.
3. The EC outer rotor DC brushless motor special-shaped magnetic shoe of claim 1, wherein: the inner arc surface and the corners of the left side surface and the right side surface are chamfer structures of 1mm x45 degrees.
4. The EC outer rotor DC brushless motor special-shaped magnetic shoe of claim 1, wherein: the distance between the upper end surface and the lower end surface is as follows: 42 + -0.1 mm.