Brushless direct current motor of plastic package fan
By designing a brushless DC motor for plastic sealing fan, using an internal rotor structure and a specific magnetic core combination, the existing motors have solved the problems in protection, vibration, environmental adaptability and service life, and achieved higher mechanical strength and magnetic density utilization.
Patent Information
- Application Number
- CN202422103998.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-08-28
- Publication Date
- 2025-06-27
- Estimated Expiration
- 2034-08-28
AI Technical Summary
Existing brushless DC motors have problems such as low protection level, large working vibration, low adaptability to high temperature and high humidity environments, short service life, difficult to ensure dynamic balance of the rotor, and low overall mechanical strength of the motor.
A plastic-sealed fan brushless DC motor is designed, adopting an internal rotor structure, the stator and rotor assembly are respectively arranged in the stator accommodation cavity and the rotor accommodation cavity. The rotor core is equipped with a core hollow part and a shock absorber. The rotor core is alternately linked by an open circuit and a closed circuit magnetic iron chip, and the rotor bracket and magnetic part are injection molded by BMC mass molding material.
The motor has achieved the advantages of small size, light weight, good insulation performance, corrosion resistance, moisture resistance, high temperature resistance and water resistance, improved vibration noise, extended service life, and improved mechanical strength and magnetic density utilization rate of magnetic circuits.
Smart Images
Figure CN223039730U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the field of DC motors, in particular to a plastic-encapsulated fan brushless DC motor. Background Art
[0002] At present, the brushless DC motors of fans applied in the small household appliance industry in the market are generally brushless DC motors with an outer rotor structure, which have problems such as low protection level, large working vibration, low adaptability to high temperature and high humidity environments, short service life, difficulty in ensuring the dynamic balance of the rotor, and low overall mechanical strength of the motor. Summary of the Utility Model
[0003] The utility model overcomes the deficiencies of the prior art and provides a plastic-encapsulated fan brushless DC motor.
[0004] To achieve the above object, the utility model adopts the following technical solutions:
[0005] A plastic-encapsulated fan brushless DC motor, characterized in that: it includes a housing, a stator accommodating cavity is arranged inside the housing, and a rotor accommodating cavity is arranged inside the stator accommodating cavity. A stator assembly is arranged in the stator accommodating cavity, and a rotor assembly is arranged in the rotor accommodating cavity. The rotor assembly includes a rotor bracket arranged in the rotor accommodating cavity, a rotor core is arranged inside the rotor bracket, a shaft mounting hole is arranged inside the rotor core, a shaft is installed in the shaft mounting hole, a core hollow part is arranged outside the shaft mounting hole inside the rotor core, a shock-absorbing member is arranged inside the core hollow part, and a plurality of magnetic members are arranged around the rotor core between the rotor core and the rotor bracket.
[0006] The plastic-encapsulated fan brushless DC motor as described above is characterized in that: the rotor core includes a plurality of rotor open-circuit magnetic path iron sheets and rotor closed-circuit magnetic path iron sheets. A plurality of rotor open-circuit magnetic path iron sheets are arranged between adjacent rotor closed-circuit magnetic path iron sheets. The rotor open-circuit magnetic path iron sheet includes an open-circuit iron core middle circular ring sheet and an open-circuit iron core outer circular ring sheet. The rotor closed-circuit magnetic path iron sheet includes a closed-circuit iron core middle circular ring sheet and a closed-circuit iron core outer circular ring sheet. A closed-circuit iron core connecting part is connected between the closed-circuit iron core middle circular ring sheet and the closed-circuit iron core outer circular ring sheet. The hollow parts between the closed-circuit iron core middle circular ring sheet and the closed-circuit iron core outer circular ring sheet and between the closed-circuit iron core middle circular ring sheet and the closed-circuit iron core outer circular ring sheet form the core hollow part.
[0007] A plastic-encased fan brushless DC motor as described above, characterized in that: there are three evenly arranged closed-circuit core connection parts between the middle circular piece of the closed-circuit core and the outer circular piece of the closed-circuit core; there are multiple magnetic part positioning grooves for installing magnetic parts on the outer side of the rotor core, there are multiple open-circuit iron core piece positioning grooves on the outer side of the outer circular piece of the open-circuit core, and there are multiple closed-circuit iron core piece positioning grooves on the outer side of the outer circular piece of the closed-circuit core. The magnetic part positioning grooves are composed of the open-circuit iron core piece positioning grooves and the closed-circuit iron core piece positioning grooves.
[0008] A plastic-encased fan brushless DC motor as described above, characterized in that: the magnetic parts include multiple N-pole magnets and S-pole magnets. The number of N-pole magnets and S-pole magnets is the same, and they are alternately arranged at intervals on the outer side of the rotor core.
[0009] A plastic-encased fan brushless DC motor as described above, characterized in that: both the shock-absorbing part and the rotor bracket are integrally formed structures made by injection molding of BMC bulk molding compound.
[0010] A plastic-encased fan brushless DC motor as described above, characterized in that: the stator assembly includes a stator support ring. There are multiple stator support winding parts extending inward and arranged around on the inner side of the stator support ring. There is a stator support insulating skeleton inside the stator support ring, and a stator winding is arranged on the stator support insulating skeleton located at the stator support winding part.
[0011] A plastic-encased fan brushless DC motor as described above, characterized in that: on both sides of the rotor accommodating cavity on the housing, there are respectively a front end cover and a rear end cover. Both ends of the rotating shaft pass through the front end cover and the rear end cover and extend out.
[0012] A plastic-encased fan brushless DC motor as described above, characterized in that: bearings are respectively arranged on the front end cover and the rear end cover. Both ends of the rotating shaft pass through the bearings and extend out. Retaining rings for preventing the bearings from moving inward are respectively arranged on the rear side of the bearing at the front end and the front side of the bearing at the rear end on the rotating shaft.
[0013] A plastic-encased fan brushless DC motor as described above, characterized in that: a gearbox assembly is arranged at the rear end of the housing. The rear end of the rotating shaft is provided with an external thread and extends into the gearbox assembly to engage with the inner gear.
[0014] A plastic-encased fan brushless DC motor as described above, characterized in that: an external connecting rod and a wire clip for leading out and fixing the power cord from the inside are arranged on the outer side surface of the housing.
[0015] The beneficial effects of the present utility model are:
[0016] The utility model arranges a stator accommodating cavity inside the casing and a rotor accommodating cavity on the inner side of the stator accommodating cavity, forming an inner rotor structure. The stator assembly and the rotor assembly are respectively arranged in the stator accommodating cavity and the rotor accommodating cavity, which simplifies the overall structure and is easy to assemble. A core hollow part is arranged inside the rotor core, and reducing the weight of the rotor enables the rotor to start quickly. A shock absorber is arranged inside the core hollow part. The shock absorber is an integral structure made by BMC bulk molding compound injection molding, which can effectively change the natural frequency of the mechanical energy transmitted from the entire magnetic field output to the rotating shaft, thereby improving the vibration and noise of the whole machine. The rotor core is composed of a rotor open-circuit magnetic path iron chip and a rotor closed-circuit magnetic path iron chip. By alternately connecting the open circuit and the closed circuit, the problem of poor concentricity caused by separating the single open circuit can be effectively avoided. At the same time, the inner magnetic part open-circuit structure prevents the leakage of magnetic flux bundles, reduces losses, improves the utilization rate of the magnetic density of the magnetic circuit, and can reduce the risk of motor demagnetization. A rotor bracket for fixing magnetic parts is arranged on the outer side of the rotor core, and the rotor bracket is an integral structure made by BMC bulk molding compound injection molding, which improves the mechanical strength between the rotor core and the magnetic parts and can effectively prevent the magnetic parts from falling off under the high-speed state of the rotor. The overall structure has the advantages of small volume, light weight, good insulation performance, corrosion resistance, moisture resistance, high temperature resistance and waterproofing. [Description of the Drawings]
[0017] Figure 1 It is a schematic structural diagram of the utility model;
[0018] Figure 2 It is a schematic structural diagram of the motor part of the utility model;
[0019] Figure 3 It is an exploded view of the motor part of the utility model;
[0020] Figure 4 It is a schematic diagram of the rotor assembly of the utility model;
[0021] Figure 5 It is one of the exploded views of the rotor assembly of the utility model;
[0022] Figure 6 It is the second exploded view of the rotor assembly of the utility model;
[0023] Figure 7 It is a schematic diagram of the rotor open-circuit magnetic path iron chip of the utility model;
[0024] Figure 8 It is a schematic diagram of the rotor closed-circuit magnetic path iron chip of the utility model;
[0025] Figure 9 It is a schematic diagram of the stator assembly of the utility model;
[0026] Figure 10 It is an exploded view of the stator assembly of the utility model;
[0027] Figure 11 This is a partial cross-sectional view of the motor of the present utility model;
[0028] Figure 12 This is the internal structure diagram of the gearbox assembly of the present utility model. [Specific embodiments]
[0029] Next, the technical solutions in the embodiments of the present utility model will be clearly and completely described in conjunction with the accompanying drawings.
[0030] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present utility model are only used to explain the relative positional relationship and movement conditions between components in a specific posture (as shown in the accompanying drawings). If this specific posture changes, the directional indications will also change accordingly. In addition, the descriptions involving "preferred", "sub-preferred", etc. in the present utility model are only for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined with "preferred" and "sub-preferred" may explicitly or implicitly include at least one such feature.
[0031] As Figures 1-12 shown, a plastic-encased fan brushless DC motor includes a motor housing 1. A stator accommodation cavity 2 is provided inside the motor housing 1, and a rotor accommodation cavity 3 is provided inside the stator accommodation cavity 2, forming an inner rotor structure. A stator assembly 4 is provided in the stator accommodation cavity 2, and a rotor assembly 5 is provided in the rotor accommodation cavity 3, which simplifies the overall structure and is easy to assemble. The rotor assembly 5 includes a rotor bracket 51 provided in the rotor accommodation cavity 3. A rotor core 52 is provided inside the rotor bracket 51. A shaft mounting hole 521 is provided inside the rotor core 52. A shaft 53 is installed in the shaft mounting hole 521. A core hollow part 522 is provided outside the shaft mounting hole 521 inside the rotor core 52, which reduces the weight of the rotor and enables the rotor to start quickly. A shock-absorbing member 54 is provided in the core hollow part 522, which can effectively change the natural frequency of the mechanical energy transmitted from the entire magnetic field output to the rotor shaft, thereby improving the vibration and noise of the whole machine. A plurality of magnetic members 55 surrounding the rotor core 52 are provided between the rotor core 52 and the rotor bracket 51. The magnetic members 55 are fixed outside the rotor core 52 through the rotor bracket 51 to achieve a tight connection. During actual operation, the inner rotor structure enables the brushless DC motor to rotate smoothly. The rotor core with a hollow structure reduces the weight of the rotor assembly, enables the rotor to start quickly, and at the same time, a shock-absorbing member is provided in the hollow part of the rotor core to improve the vibration and noise of the whole machine. The rotor bracket enables the rotor core and the magnetic members to form a tightly structured rotor assembly.
[0032] As Figures 4-8As shown, the rotor core 52 includes a plurality of rotor open-circuit magnetic path iron core sheets 523 and rotor closed-circuit magnetic path iron core sheets 524. A plurality of rotor open-circuit magnetic path iron core sheets 523 are provided between adjacent rotor closed-circuit magnetic path iron core sheets 524. By alternately connecting the open circuit and the closed circuit, the working vibration of the rotor assembly can be reduced. At the same time, the problem of poor concentricity caused by the separation of a single open circuit can be effectively avoided, the utilization rate of the magnetic density of the magnetic path can be improved, and the risk of motor demagnetization can be reduced. In the actual application of this case, three groups of rotor closed-circuit magnetic path iron core sheet groups are provided. Each group of rotor closed-circuit magnetic path iron core sheet groups includes two rotor closed-circuit magnetic path iron core sheets 524 stacked on top of each other, and the same number of rotor open-circuit magnetic path iron core sheets 523 stacked on top of each other are respectively provided between adjacent rotor closed-circuit magnetic path iron core sheet groups. In actual application, ten rotor open-circuit magnetic path iron core sheets 523 stacked on top of each other are provided between adjacent rotor closed-circuit magnetic path iron core sheet groups.
[0033] As Figure 7 shown, the rotor open-circuit magnetic path iron core sheet 523 includes an open-circuit iron core middle circular ring sheet 5231 and an open-circuit iron core outer circular ring sheet 5232. The rotor closed-circuit magnetic path iron core sheet 524 includes a closed-circuit iron core middle circular ring sheet 5241 and a closed-circuit iron core outer circular ring sheet 5242. A closed-circuit iron core connecting portion 5243 is connected between the closed-circuit iron core middle circular ring sheet 5241 and the closed-circuit iron core outer circular ring sheet 5242, realizing the alternate connection of the open circuit and the closed circuit of the magnetic path iron core sheets in the rotor core.
[0034] As Figure 8 shown, the hollow portions between the closed-circuit iron core middle circular ring sheet 5241 and the closed-circuit iron core outer circular ring sheet 5242 and between the closed-circuit iron core middle circular ring sheet 5241 and the closed-circuit iron core outer circular ring sheet 5242 form an iron core hollow portion 522, reducing the weight of the rotor.
[0035] As Figures 4-8 shown, three evenly arranged closed-circuit iron core connecting portions 5243 are provided between the closed-circuit iron core middle circular ring sheet 5241 and the closed-circuit iron core outer circular ring sheet 5242, making the closed-circuit iron core middle circular ring sheet 5241 and the closed-circuit iron core outer circular ring sheet 5242 both lightweight and stably connected; a plurality of magnetic part positioning grooves 525 for loading magnetic parts 55 are provided on the outside of the rotor core 52. A plurality of open-circuit iron core sheet positioning grooves 5233 are provided on the outside of the open-circuit iron core outer circular ring sheet 5232. A plurality of closed-circuit iron core sheet positioning grooves 5244 are provided on the outside of the closed-circuit iron core outer circular ring sheet 5242. The magnetic part positioning grooves 525 are composed of the open-circuit iron core sheet positioning grooves 5233 and the closed-circuit iron core sheet positioning grooves 5244, enabling each magnetic part to be positioned and installed on the outside of the rotor core.
[0036] As Figures 9-10As shown, the magnetic member 55 includes a plurality of N-pole magnets and S-pole magnets. The number of N-pole magnets and S-pole magnets is the same, and they are alternately and spacedly arranged outside the rotor core 52, which can make the rotor assembly rotate stably. In the actual application of this case, 5 N-pole magnets and 5 S-pole magnets are provided.
[0037] In this case, the shock-absorbing member 54 is an integrally formed structure made by BMC bulk molding compound injection molding, which improves the overall tightness and reduces the weight of the rotor; the rotor bracket 51 is an integrally formed structure made by BMC bulk molding compound injection molding, which improves the connection tightness and mechanical strength between the rotor core and the magnetic member, and can effectively prevent the magnetic member from falling off under the high-speed state of the rotor.
[0038] As Figure 10 shown, the stator assembly 4 includes a stator support ring 41. Inside the stator support ring 41, there are a plurality of stator support winding parts 42 extending inwards and arranged in a surrounding manner. Inside the stator support ring 41, there is a stator support insulating skeleton 43. On the stator support insulating skeleton 43 located at the stator support winding part 42, there is a stator winding 44, which makes the brushless DC motor form an inner rotor structure and improves the rotational stability of the rotor. In this case, the stator support insulating skeleton 43 includes an upper stator support insulating skeleton 431 sleeved from the upper side of the stator support ring 41 and a lower stator support insulating skeleton 431 sleeved from the lower side of the stator support ring 41, which is convenient for assembly.
[0039] As Figure 11 shown, on both sides of the rotor accommodating cavity 3 of the housing 1, there are respectively a front end cover 6 and a rear end cover 7. Both ends of the rotating shaft 53 pass through the front end cover 6 and the rear end cover 7 and extend out, enclosing the rotor assembly in the rotor accommodating cavity of the housing 1; there are respectively bearings 8 on the front end cover 6 and the rear end cover 7, and both ends of the rotating shaft 53 pass through the bearings 8 and extend out, which can make the rotor assembly rotate smoothly; on the rotating shaft 53, there are respectively retaining rings 9 that block the inward movement of the bearings 8 on the rear side of the bearing 8 at the front end and the front side of the bearing 8 at the rear end, preventing the bearings from moving and contacting the rotor assembly, which affects the rotation of the rotor assembly.
[0040] As Figure 1 and Figure 12 shown, a gearbox assembly 10 is provided at the rear end of the housing 1. The rear end of the rotating shaft 53 is provided with an external thread and extends into the gearbox assembly 10 to mesh with the inner gear, making the rotor assembly rotationally connected to the gearbox assembly.
[0041] As Figure 1 shown, an external connecting rod 11 and a wire clip 12 for fixing the power cord to be led out from the inside are provided on the outer side surface of the housing 1. The setting of the external connecting rod 11 facilitates the installation of the motor; the setting of the wire clip 12 prevents the power cord from being pulled and broken.
[0042] The above are only the preferred embodiments of the present utility model, and do not limit the patent scope of the present utility model accordingly. Any equivalent structural transformation made under the inventive concept of the present utility model by using the content of the specification and drawings of the present utility model, or directly or indirectly applied in other related technical fields, is included in the patent protection scope of the present utility model.
Claims
1. A plastic-encapsulated fan brushless DC motor, characterized in that: The invention comprises a housing (1), wherein a stator accommodating chamber (2) is provided in the housing (1), and a rotor accommodating chamber (3) is provided inside the stator accommodating chamber (2), a stator assembly (4) is provided in the stator accommodating chamber (2), a rotor assembly (5) is provided in the rotor accommodating chamber (3), the rotor assembly (5) comprises a rotor support (51) provided in the rotor accommodating chamber (3), a rotor core (52) is provided in the rotor support (51), a rotating shaft mounting hole (521) is provided in the rotor core (52), a rotating shaft (53) is mounted in the rotating shaft mounting hole (521), a core hollow portion (522) is provided in the rotor core (52) outside the rotating shaft mounting hole (521), a shock absorbing member (54) is provided in the core hollow portion (522), and a plurality of magnetic members (55) arranged around the rotor core (52) are provided between the rotor core (52) and the rotor support (51).
2. The plastic-encapsulated fan brushless DC motor according to claim 1, characterized in that: The rotor core (52) comprises a plurality of rotor open magnetic circuit core pieces (523) and a rotor closed magnetic circuit core piece (524), a plurality of rotor open magnetic circuit core pieces (523) are arranged between adjacent rotor closed magnetic circuit core pieces (524), the rotor open magnetic circuit core pieces (523) comprise an open core middle annular piece (5231) and an open core outer annular piece (5232), and the rotor closed magnetic circuit core piece (524) comprises a closed core middle annular piece (5241) and an outer circular ring piece (5242) of the closed-circuit core, the middle circular ring piece (5241) of the closed-circuit core and the outer circular ring piece (5242) of the closed-circuit core are connected with a closed-circuit core connecting portion (5243), and the hollow portions between the middle circular ring piece (5241) of the closed-circuit core and the outer circular ring piece (5242) of the closed-circuit core and between the middle circular ring piece (5241) of the closed-circuit core and the outer circular ring piece (5242) of the closed-circuit core form an iron core hollow portion (522).
3. The plastic-encapsulated fan brushless DC motor according to claim 2, characterized in that: Three evenly arranged closed-circuit core connecting parts (5243) are provided between the closed-circuit core middle annular piece (5241) and the closed-circuit core outer annular piece (5242); a plurality of magnetic piece positioning grooves (525) for inserting magnetic pieces (55) are provided on the outer side of the rotor core (52); a plurality of open-circuit core piece positioning grooves (5233) are provided on the outer side of the open-circuit core outer annular piece (5232); a plurality of closed-circuit core piece positioning grooves (5244) are provided on the outer side of the closed-circuit core outer annular piece (5242); and the magnetic piece positioning grooves (525) are composed of open-circuit core piece positioning grooves (5233) and closed-circuit core piece positioning grooves (5244).
4. A plastic-encapsulated fan brushless DC motor according to claim 1 or 3, characterized in that: The magnetic member (55) includes a plurality of N-polarity magnets and S-polarity magnets, the number of the N-polarity magnets and the number of the S-polarity magnets are the same, and the magnets are alternately arranged at intervals outside the rotor core (52).
5. The plastic-encapsulated fan brushless DC motor according to claim 1, characterized in that: The shock absorbing member (54) and the rotor support (51) are both integral structures made by injection molding of BMC bulk molding compound.
6. The plastic-encapsulated fan brushless DC motor according to claim 1, characterized in that: The stator assembly (4) comprises a stator support ring (41), a plurality of stator support winding portions (42) extending inwardly and arranged in a surrounding manner are arranged inside the stator support ring (41), a stator support insulating frame (43) is arranged inside the stator support ring (41), and a stator winding (44) is arranged on the stator support insulating frame (43) located at the stator support winding portion (42).
7. The plastic-encapsulated fan brushless DC motor according to claim 1, characterized in that: A front end cover (6) and a rear end cover (7) are respectively provided on both sides of the rotor accommodating chamber (3) on the casing (1), and two ends of the rotating shaft (53) respectively pass through the front end cover (6) and the rear end cover (7) to extend out.
8. The plastic-encapsulated fan brushless DC motor according to claim 7, characterized in that: The front end cover (6) and the rear end cover (7) are respectively provided with bearings (8), and both ends of the rotating shaft (53) extend through the bearings (8), and retaining rings (9) for preventing the bearings (8) from moving inwards are respectively provided on the rear side of the bearings (8) at the front end and the front side of the bearings (8) at the rear end of the rotating shaft (53).
9. The plastic-encapsulated fan brushless DC motor according to claim 1, characterized in that: A gear box assembly (10) is disposed at the rear end of the housing (1), and an external thread is disposed at the rear end of the rotating shaft (53) and extends into the gear box assembly (10) to mesh with the inner gear.
10. The plastic-encapsulated fan brushless DC motor according to claim 1, characterized in that: An external connecting rod (11) and a wire clamp (12) for fixing a power line drawn out from the inside are provided on the outer side of the housing (1).