KR20220113570A - BLDC Motor rotor housing - Google Patents

Abstract

The present invention relates to a rotor housing of a BLDC motor with improved noise reduction performance. According to the present invention, noise and vibration are reduced by improving resistance to noise with vibration proof which improves resonance by avoiding frequencies of wind noise components caused by fan blades of switching noise and caulking noise components when the motor rotates through a structural change in the rotor housing. The rotor housing of a BLDC motor includes a rotor housing, a rotor shaft, and a permanent magnet. In addition, the rotor housing includes a damping wing formed with a certain height and width and a damping hollow formed with a certain depth to express noise reduction performance by vibration proof properties of damping and breaking noise components generated during rotation on an outer circumference of the rotor housing. 1020220113570 ROTOR HOUSING OF BLDC MOTOR WITH IMPROVED NOISE REDUCTION PERFORMANCE The present invention relates to a rotor housing of a BLDC motor with improved noise reduction performance. According to the present invention, noise and vibration are reduced by improving resistance to noise with vibration proof which improves resonance by avoiding frequencies of wind noise components caused by fan blades of switching noise and caulking noise components through a structural change in the rotor housing when the motor rotates. The rotor housing of a BLDC motor includes a rotor housing, a rotor shaft, and a permanent magnet. In addition, the rotor housing includes a damping wing formed with a certain height and width and a damping hollow formed with a certain depth to express noise reduction performance by vibration proof properties of damping and breaking noise components generated during rotation on an outer circumference of the rotor housing.

Description

BLDC motor rotor housing with improved noise reduction performance

The present invention relates to a rotor housing of a BLDC motor with improved noise reduction performance, and more particularly, the noise component of the wind by the fan blades of the switching noise and caulking noise components during the rotation of the motor through structural change of the rotor housing. It relates to a rotor housing of a BLDC motor that reduces noise and vibration by improving resistance to noise by vibration-proofing which improves resonance by avoiding the frequency of

2. Description of the Related Art In general, a motor is a device for obtaining rotational force by converting electrical energy into mechanical energy, and is widely used from home electronic products to industrial devices, and is largely divided into DC motors and AC motors.

In the DC motor, the brush-attached motor functions to flow and rectify current to the coil by contact between the commutator and the brush, but has a disadvantage in that the brush is worn. In order to overcome the above disadvantages, a brushless BLDC motor is mainly used.

The BLDC motor not only reduces mechanical or electrical noise, but also has the advantage of being able to control various speeds from low to high speed.

The BLDC motor includes a stator and a rotor configured to be rotatably provided inside or outside the stator. In addition, the rotor shaft is press-fitted to the center of the rotor. A plurality of radially provided teeth are configured in the stator, and slots in which a coil is wound are formed on the teeth.

As shown in FIG. 1, the BLDC motor includes a rotor housing 1, a permanent magnet 2 configured to be symmetrical to one side of the rotor housing 1, and a magnetic field relationship between the permanent magnet 2 A stator assembly 3 supporting the rotor housing 1 to be rotated by a rotor shaft 4 having one end fixed to the center of the rotor housing 1, At least one bearing 5 for supporting the rotation of the rotor shaft 4, and a bearing holder 6 for supporting the configuration position of the bearing 5 is configured.

The conventional rotor housing 1 is formed into a straight cylindrical shape with both ends open or one end blocked by a press working method.

However, when the rotor housing 1 formed in a straight cylindrical shape is vibrating due to non-uniform rotation during rotation or an excitation source caused by current ripple or caulking torque during switching, a ringing phenomenon occurs in the rotor housing 1 There is a problem in that the generated resonance acts as a fatal cause of noise and vibration by reacting with the natural frequency of the rotor housing 1 to provide a cause of resonance.

Republic of Korea Patent No. 10-1603206 (2016.03.14. Announcement) Republic of Korea Patent No. 10-961654 (2010.06.09. Announcement) Korean Patent No. 10-1189107 (Announced on October 10, 2012)

As a proposal to solve the above problems, an object of the present invention is to avoid the frequency of the noise component of the wind caused by the fan blades of the switching noise and caulking noise component during the rotation of the motor through structural change of the rotor housing. An object of the present invention is to provide a rotor housing of a BLDC motor that reduces noise and vibration by improving resistance to noise with vibration-proofing for improving resonance.

The present invention for achieving the above object, in the rotor housing of a BLDC motor comprising a rotor housing, a rotor shaft, and a permanent magnet, attenuates and fractures a noise component generated during rotation on the outer periphery of the rotor housing It is characterized in that it comprises a; damping wing formed with a predetermined height and width and a damping hole formed with a predetermined depth so that the noise reduction performance is expressed by the vibration-proof property.

In the present invention, it is preferable that the damping blades and the damping holes are sequentially formed at regular intervals along the central axis direction of the rotor housing.

In the present invention, the damping blade and the damping hole are formed in a spiral or knurled type continuously formed on the outer periphery of the rotor housing; it is preferable to be formed.

In the present invention, it is preferable to further include; an insert housing formed by an insert injection method to protect the rotor housing while amplifying the fixing force to the rotor housing and the rotor shaft.

In the present invention, the rotor housing is formed of a predetermined thickness, and is sequentially stacked to break the noise frequency so that the noise reduction performance is expressed.

In the present invention, the rotor housing is formed with a certain thickness, and is sequentially stacked to break the noise frequency and is composed of a fragment ring so that noise reduction performance is expressed; Preferably, the fragment ring includes a large-diameter fragmentation ring and a small-diameter fragmentation ring having the same inner diameter, but having a difference in outer diameter to have vibration resistance against noise components.

In the present invention, the rotor housing is formed to a certain thickness, and is sequentially stacked to break the noise frequency and is composed of a fragment ring so that noise reduction performance is expressed; The fragment ring has an outer diameter boss formed to a predetermined thickness and forming an outer diameter of the rotor housing; and a step piece bent at a certain height from one end of the outer-diameter boss and formed to have a size smaller than the outer diameter of the outer-diameter boss.

In the present invention, the fragment ring includes a positioning groove having a predetermined depth on one side; It is preferable to include; a positioning pin inserted into the positioning groove to prevent defective assembly and provide convenience of assembly when the fragment rings are sequentially stacked.

According to the present invention, damping blades and damping holes are formed on the outer periphery of the rotor housing to avoid frequencies such as switching noise components, caulking noise components, and wind noise components caused by the fan blades during rotation, thereby improving resonance. It has the effect of having a noise-reducing performance in the end by making it have vibration-proofing properties.

1 is a cross-sectional view of a typical BLDC motor.
2 is a cross-sectional view of a BLDC motor according to a first embodiment of the present invention.
3 is a perspective view of a rotor housing according to a first embodiment of the present invention;
4 is a cross-sectional view of the rotor housing according to the first embodiment of the present invention.
5 is a view showing another example of the rotor housing according to the first embodiment of the present invention,
5a is helical, 5b is knurled.
6 is a graph showing natural frequencies according to a first embodiment of the present invention;
6a is a conventional rotor housing, and 6b is a rotor housing of the first embodiment.
7 is a graph showing a resonance frequency of 9,000 RPM according to the first embodiment of the present invention,
7a is a conventional rotor housing, and 7b is a rotor housing of the first embodiment.
8 is a cross-sectional view of a BLDC motor according to a second embodiment of the present invention.
9 is a perspective view of a rotor housing according to a second embodiment of the present invention.
10 is a cross-sectional view of a rotor housing according to a second embodiment of the present invention.
11 is a perspective view of a fragment ring showing another example of the second embodiment of the present invention.
12 is a cross-sectional view of a fragment ring showing another example of the second embodiment of the present invention.
13 is a cross-sectional view of a fragment ring showing another example of the second embodiment of the present invention.

Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings as follows (the same reference numerals are used for the same components as in the prior art, and detailed description thereof will be omitted).

<First embodiment>

As shown in FIG. 2, the BLDC motor of the first embodiment includes a rotor housing 10, a permanent magnet 2, a stator assembly 3, a rotor shaft 4, a bearing 5, and a bearing holder. (6) is included.

As shown in FIGS. 3 and 4 , the rotor housing 10 is generally formed in a straight cylindrical shape.

In addition, the rotor housing 10 is configured with a plurality of damping blades 110 formed to have a predetermined height and width on the outer periphery.

The damping blade 110 is formed with a predetermined height and width on the outer periphery of the rotor housing 10, and the switching noise component, caulking noise component, and wind noise component generated during rotation are the noise component of the fan. By breaking the transmission along the surface of the rotor housing 10 and preventing or minimizing the cause of resonance formed in response to the natural frequency of the rotor housing 10, noise and vibration are reduced.

In this case, when a plurality of the rotor housing 10 is formed in the central axis direction of the rotor housing 10 with a certain height and width of the damping blade 110, the damping hole 120 naturally having a certain depth is provided. is formed

As a result, a plurality of damping blades 110 are formed at regular intervals with a certain height and width on the outer periphery of the rotor housing 10, and a damping hole 120 of a certain depth is formed between the plurality of damping blades 110. By being naturally formed, noise reduction performance is expressed by breaking the vibration frequency generated during rotation by the interaction of the damping blade 110 and the damping hole 120 .

In addition, the damping blade 110 and the damping hole 120 are formed on the outer periphery of the rotor housing 10 by an embossed or engraved processing method.

In addition, the damping wing 110 and the damping hole 120 of the rotor housing 10 are configured as a separate type having a mutually separated shape.

Of course, the present invention is not limited thereto, and the damping blade 110 and the damping hole 120 may be spirally formed to have a continuous joint relationship on the outer periphery of the rotor housing 10 as shown in FIG. 5A . have.

Alternatively, the damping blade 110 and the damping hole 120 may be formed in a knurled type so that noise reduction performance can be expressed by breaking the frequency, as shown in FIG. 5b .

Of course, it is not limited thereto, and the damping wing 110 and the damping hole 120 have a structure or shape capable of damping or breaking the ringing phenomenon in the rotor housing during rotation, as well as the above-described separation type, spiral, and knurled type. If anything, you can use it.

On the other hand, looking at the natural frequency of the rotor housing as shown in Fig. 6, in the case of the conventional straight cylindrical rotor housing as shown in Fig. 6a, the natural frequency frequency level of 3.0 kHz is -37 dB, and the attenuation of the present invention as shown in Fig. 6b As it can be seen that, in the case of the rotor housing in which the blades and the damping hole are formed, the natural frequency frequency level of 2.3 kHz is low vibration by -60 dB. improvement can be seen.

In addition, looking at the resonance frequency of 9,000 RPM for the rotor housing as shown in FIG. 7, in the case of the conventional straight cylindrical rotor housing as shown in FIG. 7A, the natural frequency frequency level of 3.0 kHz, which is a switching frequency due to resonance, is -30 dB and, as shown in FIG. 7b, in the case of the rotor housing in which the damping blade and the damping hole of the present invention are formed, the natural frequency frequency level of 3.0 kHz, which is the switching frequency due to resonance, is low vibration by -50 dB, compared to the conventional one, the damping blade and It can be seen that, in the rotor housing of the present invention including the damping hole, the noise due to the resonance generated when the natural frequency and the switching noise component meet is improved to 20 dB.

<Second embodiment>

The same reference numerals are used for the same components as those of the first embodiment, and a detailed description thereof will be omitted.

As shown in FIG. 8, the BLDC motor of the second embodiment includes a rotor housing 10, a permanent magnet 2, a stator assembly 3, a rotor shaft 4, a bearing 5, and a bearing holder. Including (6), the rotor housing 10 and the rotor shaft 2 are formed by an insert injection method to amplify the fixing force for the rotor housing 10 and the rotor shaft 2 and the rotor housing 10 It includes an insert housing 20 to protect it.

As shown in FIG. 8 , the insert housing 20 has a certain thickness to protect the rotor housing 10 as well as to keep the rotor shaft 2 firmly fixed to the rotor housing 10 . is formed with

On the other hand, the rotor housing 10 can be configured by adopting a 'U'-shaped cylinder with one end blocked as in the first embodiment, but by being formed in a cylindrical shape with both ends communicating, the insert housing 20 The rotor shaft 2 is configured to be fixed by the

In this case, the rotor housing 10 is formed by stacking the fragment rings 12 having a predetermined thickness as shown in FIGS. 9 and 10 . That is, by sequentially stacking the fragment rings 12 to form one rotor housing 10, as a separation film is formed by the fragment rings 12, the damping blade 110 and damping of the first embodiment It allows the noise reduction performance to be expressed without artificially forming the ball 120 .

Accordingly, the rotor housing 10 is formed in a state in which a plurality of fragment rings 12 are sequentially stacked, and the rotor housing 10 by the fragment rings 12 is formed by an insert injection method ( The fragment ring 12 stacked by 20) can maintain a firmly fixed state.

In addition, the fragment ring 12 of the rotor housing 10 can be changed into various structures or shapes.

For example, as shown in FIGS. 11 and 12 , the fragment ring has the same inner diameter, but is divided into a large-diameter fragment ring 122 and a small-diameter fragment ring 124 having a difference in the outer diameter, and the large-diameter fragment ring 122 ) and the small-diameter fragment rings 124 are alternately and sequentially stacked to form one rotor housing 10 .

That is, when the large-diameter fragment ring 122 and the small-diameter fragment ring 124 are alternately stacked sequentially, the portion corresponding to the damping wing 110 of the rotor housing 10 of the first embodiment is the large-diameter fragment ring 122. It is replaced, and as the damping hole 120 is replaced with the small-diameter fragment ring 124, the noise reduction performance is further improved.

In addition, the large-diameter fragment ring 122 and the small-diameter fragment ring 124 are formed with a positioning groove 126 having a predetermined depth, are inserted into the positioning groove 126, and are alternately stacked in sequence. A positioning pin 127 for preventing assembly defects and convenience of assembly for the ring 122 and the small-diameter fragment ring 124 is configured.

In this case, the positioning groove 126 and the positioning pin 127 are configured so as to be symmetrical to each other in plurality, so as not to interfere with the rotation of the motor.

Alternatively, as shown in FIG. 13, the fragment ring 128 has an outer diameter boss 128a formed to a predetermined thickness to form an outer diameter of the rotor housing 10, and a predetermined height from one end of the outer diameter boss 128a. It is formed of a stepped piece 128b that is bent to have it.

Accordingly, when the fragment rings 128 are sequentially stacked, the damping hole 120 of the first embodiment is replaced by making a gap between the fragment rings 128 stacked by the stepped piece 128b. and the outer diameter boss 128a replaces the damping blade 110 of the first embodiment, thereby further improving the noise reduction performance.

In addition, for the convenience of assembly, the fragment ring 128 may include a positioning groove and a positioning pin.

What has been described above is only one embodiment for implementing the rotor housing of the BLDC motor with improved noise reduction performance, and the present invention is not limited to the above embodiment. Those of ordinary skill in the art to which the present invention pertains will understand that various modifications can be made without departing from the gist of the present invention.

10: rotor housing 110: damping wing
120: damping hole 12, 128: fragment ring
122: large diameter cut ring 124: small diameter cut ring
126: positioning groove 127: positioning pin
128a: outer diameter boss 128b: step

Claims (8)

In the rotor housing of the BLDC motor comprising a rotor housing, a rotor shaft, and a permanent magnet,
Damping wing formed in a predetermined height and width and a damping hole formed in a predetermined depth so that the noise reduction performance is expressed by the vibration-proof property to attenuate and fracture the noise component generated during rotation on the outer periphery of the rotor housing;
The rotor housing of the BLDC motor with improved noise reduction performance, characterized in that it comprises a.
The method according to claim 1,
The rotor housing of the BLDC motor with improved noise reduction performance, characterized in that the damping blades and the damping holes are sequentially formed at regular intervals along the central axis direction of the rotor housing.
The method according to claim 1,
The damping wing and the damping hole are spiral or knurled type continuously formed on the outer periphery of the rotor housing;
The rotor housing of the BLDC motor with improved noise reduction performance, characterized in that it is formed of
The method according to claim 1,
an insert housing formed by an insert injection method to amplify the fixing force to the rotor housing and the rotor shaft and to protect the rotor housing;
The rotor housing of the BLDC motor with improved noise reduction performance, characterized in that it further comprises.
The method according to claim 1, The rotor housing,
Segment rings formed to a certain thickness and stacked sequentially to break down noise frequencies to express noise reduction performance;
The rotor housing of the BLDC motor with improved noise reduction performance, characterized in that it consists of
The method according to claim 1, The rotor housing,
It is formed to a certain thickness, and is sequentially stacked to break the noise frequency so that the noise reduction performance is expressed as a fragment ring;
The fragment ring has the same inner diameter, but a large diameter fragment ring and a small diameter fragment ring to have a difference in the outer diameter to have vibration resistance against noise components;
The rotor housing of the BLDC motor with improved noise reduction performance, characterized in that it consists of
The method according to claim 1, The rotor housing,
It is formed to a certain thickness, and is sequentially stacked to break the noise frequency so that the noise reduction performance is expressed as a fragment ring;
The fragment ring has an outer diameter boss formed to a predetermined thickness and forming an outer diameter of the rotor housing; and
a step piece bent at a certain height from one end of the outer-diameter boss and formed to have a size smaller than the outer diameter of the outer-diameter boss;
The rotor housing of the BLDC motor with improved noise reduction performance, characterized in that it is formed of
8. The method according to any one of claims 5 to 7,
The fragment ring includes a positioning groove having a predetermined depth on one side;
a positioning pin inserted into the positioning groove to prevent defective assembly and provide convenience of assembly when the fragment rings are sequentially stacked;
The rotor housing of the BLDC motor with improved noise reduction performance, characterized in that it comprises a.

Images