Air-cooled permanent magnet brushless direct current motor and cleaning equipment

Abstract

The utility model discloses an air cooling type permanent magnet brushless direct current motor and cleaning equipment, which comprises a casing, a stator and a rotor, a rotating shaft is arranged in the rotor, the stator is arranged in the casing, the rotor is arranged in the stator, the front end of the rotating shaft extends out of the front end of the casing, a driving assembly is arranged in the rear end of the casing, an impeller is arranged on the rotating shaft, and the impeller is arranged on the casing. The impeller is located inside the front end of the machine shell, an air inlet hole is formed in the side wall of the rear end of the machine shell, an air outlet hole is formed in the side wall of the front end of the machine shell, an air flow channel is formed in the stator, and external air enters the machine shell from the air inlet hole and then is exhausted through the driving assembly, the air flow channel and the air outlet hole in sequence. According to the utility model, a lateral air circulation mode of air outlet and air inlet on the side wall is adopted, so that the problem of poor cooling effect caused by backflow of hot air flow can be avoided, and the heat dissipation and cooling performance is improved.

Description

Technical Field

[0001] This utility model relates to a DC motor, specifically an air-cooled permanent magnet brushless DC motor and a cleaning device. Background Technology

[0002] Permanent magnet brushless DC motors are used in many different types of equipment. During operation, the motor generates heat due to copper and iron losses, electromagnetic induction, and bearing friction. This heat needs to be dissipated promptly to cool the internal components; otherwise, overheating can damage them. Generally, fan motors that operate for extended periods use heat dissipation fins on the motor casing and a fan at the rear to actively cool the casing. The impeller is located at the rear cover, and airflow first passes over it, heating it up. Some DC motors do not have fans, resulting in even worse heat dissipation.

[0003] Traditional AC motors have cooling fans, but these fans are typically located at the rear of the casing, away from the output shaft, meaning the fan blades are rear-mounted. Air is drawn in or out from the rear, resulting in relatively limited cooling performance. Patent CN214480140U discloses an internal cooling structure for a motor with a reverse-mounted impeller, comprising a motor housing and a compressor housing. The motor housing contains a rotor and a stator, while the compressor housing is located at the front end of the motor housing and contains an impeller. In this invention, the impeller is reverse-mounted within the compressor housing, and the impeller is connected to one end of the rotor. The key features are: end caps at both the front and rear ends of the motor housing, each with an air vent; a flow channel on the inner wall of the motor housing, positioned between the motor housing and the stator, running axially along the motor housing; the flow channel communicating with the air vent; a fan inlet on the compressor housing, communicating with the air vent on the end cap at the front end of the motor housing; and a fan outlet on the compressor housing. In the aforementioned patent, air enters from the rear of the casing, then passes through the stator and rotor for cooling, and finally exits from the front, discharging the gas into the compressor casing. The gas flow direction is axial, meaning air enters at one end and exits at the other. This method is prone to backflow, causing some of the hotter gas after heat exchange to flow back into the motor casing, thus hindering effective cooling. Furthermore, the aforementioned prior patent primarily aims to provide airflow. By using external gas to flow axially, it serves both cooling and airflow purposes, and is mainly used in blower-type air-blowing equipment. Summary of the Invention

[0004] To address the aforementioned technical problems, this invention provides an air-cooled permanent magnet brushless DC motor and a cleaning device.

[0005] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0006] A wind-cooled permanent magnet brushless DC motor includes a housing, a stator, and a rotor. The rotor has a rotating shaft inside, the stator is installed inside the housing, and the rotor is located inside the stator. The front end of the rotating shaft extends from the front end of the housing, and a drive assembly is located inside the rear end of the housing. An impeller is mounted on the rotating shaft and is located inside the front end of the housing. An air inlet is located on the rear side wall of the housing, and an air outlet is located on the front side wall of the housing. The stator has a gas flow channel. External air enters the housing through the air inlet and is discharged sequentially through the drive assembly, the gas flow channel, and the air outlet.

[0007] As a further improvement, the housing includes a main housing and a rear housing, the rear housing is mounted on the rear end of the main housing, the drive assembly is mounted inside the rear housing, the air inlet is located on the side wall of the rear housing, and the air outlet is located on the side wall of the main housing.

[0008] As a further improvement, a front cover is installed at the front end of the main housing, a rear cover is installed at the rear end of the main housing, the rear housing is connected to the rear cover, and a tail cover is installed on the rear housing. The tail cover, the front cover and the rear cover are each provided with several through holes. The front end of the rotating shaft extends out from the front cover, and the rear end of the rotating shaft passes through the rear cover and the drive assembly.

[0009] As a further improvement, the gas flow channels are multiple and distributed along the axial direction of the stator.

[0010] As a further improvement, the drive assembly includes a drive board and components mounted on the drive board. A rotating shaft passes through the drive board, and the drive board is vertically connected to the rear end cover. The drive board is provided with several vent holes, which communicate with through holes on the rear end cover.

[0011] As a further improvement, at least two air inlets and at least two air outlets are provided, with the at least two air inlets evenly distributed on the side wall of the rear housing and the at least two air outlets evenly distributed on the side wall of the main housing.

[0012] As a further improvement, the rotor is fitted with a protective sleeve.

[0013] As a further improvement, the air inlet on the rear housing sidewall faces the components on the drive plate, or the air inlet is located in the area behind the components on the drive plate.

[0014] As a further improvement, the drive plate has a groove on its side, and after the drive plate is connected to the rear end cover, the groove communicates with the through hole on the rear end cover.

[0015] A cleaning device includes the air-cooled permanent magnet brushless DC motor described above.

[0016] Compared with the prior art, the present invention has the following beneficial technical effects:

[0017] It adopts a side-mounted gas flow form with side wall air outlet and inlet. The gas enters and exits from the side wall, and the impeller is positioned in front. After the outside air enters the casing, it does not come into contact with the impeller first, but directly contacts the drive components and stator for heat exchange, thus achieving cooling. This can avoid the problem of poor cooling effect caused by hot air backflow, improve heat dissipation and cooling performance, and is especially suitable for driving cleaning rollers of various cleaning equipment, such as floor scrubber roller brushes and vacuum cleaner brushes. Attached Figure Description

[0018] Figure 1 This is a three-dimensional structural diagram of the present invention;

[0019] Figure 2 This is a schematic cross-sectional view of the present invention.

[0020] Figure 3 This is an exploded structural diagram of the present invention.

[0021] Figure label:

[0022] Main housing 1, rear housing 2, stator 3, rotor 4, rotating shaft 5, impeller 6, air inlet 8, air outlet 9, gas flow channel 10, sheath 11, front cover 12, rear cover 13, tail cover 14, drive plate 16, components 17, air passage 18, groove 19, through hole 20. Detailed Implementation

[0023] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0024] In the description of this invention, it should be understood that if terms such as "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise" are used to indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, they are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of the stated features. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0025] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection. They can refer to a mechanical connection or an electrical connection. They can refer to a direct connection or an indirect connection through an intermediate medium, and they can refer to the internal communication of two components or the interaction between two components. For those skilled in the art, the specific meaning of the above terms in this invention can be understood according to the specific circumstances.

[0026] Example 1

[0027] refer to Figure 1-3 As shown, an air-cooled permanent magnet brushless DC motor includes a housing, a stator 3, and a rotor 4. A rotating shaft 5 is housed within the rotor 4. The stator 3 is mounted inside the housing, and the rotor 4 is located within the stator 3. The front end of the rotating shaft 5 extends from the front end of the housing. A drive assembly is located inside the rear end of the housing. An impeller 6 is mounted on the rotating shaft 5 and is located inside the front end of the housing. An air inlet 8 is located on the rear side wall of the housing, and an air outlet 9 is located on the front side wall. A gas flow channel 10 is located within the stator 3. External air enters the housing through the air inlet 8 and exits sequentially through the drive assembly, the gas flow channel 10, and the air outlet 9. The stator and rotor are existing technology structures, including necessary coils. The drive assembly is powered externally and connected to the stator, controlling its operation. The overall design features side-wall air inlet and outlet, providing directional airflow and reducing the risk of backflow, thus improving heat dissipation and cooling.

[0028] The rotor 4 is fitted with a protective sleeve 11, which can protect the rotor.

[0029] When the stator 3 is energized, it generates a magnetic field that causes the rotor 4 to rotate, which in turn drives the shaft 5 to rotate. The impeller 6 rotates synchronously with the shaft 5. During the rotation, a certain negative pressure environment is formed inside the casing. Outside air enters through the air inlet 8. Since the impeller 6 is located in the front end area of ​​the casing, an adsorption force is formed at the front end of the casing, which attracts the air. This causes the air entering through the air inlet 8 to flow towards the front end of the casing. When it passes through the drive assembly, the air temperature is low, and it exchanges heat with the drive assembly, carrying away the heat from the drive assembly. Then the air enters the gas flow channel inside the stator. The stator temperature is high, and the air carries away the heat further. Finally, the heated air is discharged from the air outlet. Because the impeller is a front-mounted structure, it always maintains an adsorption force at the front end of the casing, which makes the gas flow directionally from the air inlet to the air outlet. The gas that has undergone heat exchange will not flow back to the rear of the drive assembly.

[0030] Example 2

[0031] refer to Figure 1-3 As shown, an air-cooled permanent magnet brushless DC motor includes a housing, a stator 3, and a rotor 4. A rotating shaft 5 is housed within the rotor 4. The stator 3 is installed inside the housing, and the rotor 4 is located within the stator 3. The front end of the rotating shaft 5 extends from the front end of the housing. A drive assembly is located inside the rear end of the housing. An impeller 6 is mounted on the rotating shaft 5 and is located inside the front end of the housing. An air inlet 8 is located on the rear side wall of the housing, and an air outlet 9 is located on the front side wall. A gas flow channel 10 is located inside the stator 3. External air enters the housing through the air inlet 8 and exits sequentially through the drive assembly, the gas flow channel 10, and the air outlet 9. For ease of installation and maintenance, the housing comprises a main housing 1 and a rear housing 2, which are assembled together. The main housing 1 is used to assemble and accommodate the rotor 4 and the stator 3, while the rear housing 2 is used to assemble the drive assembly. The air inlet 8 is located on the side wall of the rear housing 2, and the air outlet 9 is located on the side wall of the main housing 1, forming a front-to-rear air outlet structure.

[0032] A front cover 12 is installed at the front end of the main housing 1, and a rear cover 13 is installed at the rear end of the main housing 1. The rear housing 2 is connected to the rear cover 13, and a tail cover 14 is installed on the rear housing 2. The tail cover 14, front cover 12, and rear cover 13 are all provided with several through holes 20. Bearings 15 are installed inside the front cover 12 and the rear cover 13. The front end of the rotating shaft 5 extends from the bearing 15 installed inside the front cover 12, and the rear end of the rotating shaft 5 passes through the bearing and drive assembly installed on the rear cover 13. The bearings at both ends make the rotating shaft more stable during rotation. The through holes on the front and rear covers ensure air convection and improve heat dissipation. The through holes on the tail cover allow direct communication with external gas. The heat generated by the drive assembly raises the temperature of the gas inside the rear housing. Based on the characteristic that high-temperature gas flows towards low-temperature areas, some gas will also flow out from the tail cover, further increasing heat dissipation. The distance between the air inlet and outlet is less than the distance between the tail cover and the air inlet; therefore, the air inlet allows for a large intake of air.

[0033] The air inlet is located in the area between the tail cover and the rear cover, and the air outlet is located in the area behind the front cover. Therefore, as the impeller rotates, the generated gas will enter in large quantities through the air inlet and then exit through the air outlet, instead of being discharged directly from the front cover.

[0034] The gas flow channel 10 has several channels and is distributed along the axial direction of the stator. Gas flows through the gas flow channel and carries away heat from the inside of the stator to achieve cooling.

[0035] It is preferable to have the same number of air inlets and outlets, preferably in a long, narrow shape. Alternatively, the outlet can be designed to be larger than the inlet to ensure that air is not obstructed during exhaust.

[0036] The rear end cover and the front end cover can be installed and connected to the main housing through a snap-fit ​​structure. The rear housing can be locked to the rear end cover with screws. The tail cover can be installed and connected to the rear housing through a snap-fit ​​structure or by locking it with screws.

[0037] Example 3

[0038] refer to Figure 1-3As shown, an air-cooled permanent magnet brushless DC motor includes a housing, a stator 3, and a rotor 4. A rotating shaft 5 is housed within the rotor 4. The stator 3 is mounted inside the housing, and the rotor 4 is located within the stator 3. The front end of the rotating shaft 5 extends from the front end of the housing. A drive assembly is located inside the rear end of the housing. An impeller 6 is mounted on the rotating shaft 5 and is located inside the front end of the housing. An air inlet 8 is located on the rear side wall of the housing, and an air outlet 9 is located on the front side wall. A gas flow channel 10 is located within the stator 3. External air enters the housing through the air inlet 8 and exits sequentially through the drive assembly, the gas flow channel 10, and the air outlet 9. The drive assembly includes a drive plate 16 and components 17 mounted on the drive plate 16, such as capacitors and control chips, used to control and supply power to the stator 3. The stator 3 provides a magnetic field, enabling the rotor 4 to rotate within the stator 3. The rotating shaft 5 passes through the drive plate 16, which is vertically mounted and connected to the rear end cover 13. The drive plate 16 has several air vents 18, which communicate with the through holes 20 on the rear end cover 13. The drive plate 16 and the rear end cover 13 are fitted together, with the components 17 facing the rear housing. The air inlet 8 on the side wall of the rear housing 2 faces the components 17 on the drive plate 16. External air enters the rear housing 2 through the air inlet 8 and first contacts the drive plate 16 and components 17, thus carrying away heat from them and providing a cooling effect. Because there are multiple air inlets evenly distributed on the rear housing, external air enters from multiple different directions, thus cooling the drive plate from different angles and improving heat dissipation.

[0039] The drive plate 16 has a groove 19 on its side. After the drive plate 16 is connected to the rear end cover 13, the groove 19 communicates with the through hole 20 on the rear end cover 13. The groove also allows gas to pass through, and combined with the vent holes on the drive plate, ensures smooth air passage. If a large amount of external air enters, and some gas cannot enter the main housing through the vent holes of the drive plate and the through hole of the rear end cover in time, some gas can flow out from the tail cover, thus carrying away heat.

[0040] In addition, the middle area of ​​the shaft is larger, while the two ends of the shaft are smaller for easy installation. The mounting holes on the impeller are larger, while the holes on the drive plate for the shaft to pass through are smaller, which facilitates the assembly of the shaft. The shaft passes through the impeller and then through the rear end cover and drive plate in sequence, reducing the difficulty of installation.

[0041] This invention relates to a brushless DC motor, which primarily provides torque. Through the impeller-front structure and the side-wall air intake and exhaust structure, it does not need to consider the influence of wind force and can be used to drive the cleaning rollers of various cleaning equipment, such as floor scrubber rollers and vacuum cleaner brushes.

[0042] When this utility model is in operation:

[0043] The drive assembly provides power and control to the stator, generating a magnetic field inside. The rotor rotates within the stator, which in turn drives the shaft to rotate. Simultaneously, the shaft drives the impeller located at the front end of the main housing to rotate synchronously, expelling air towards the exhaust port at the front, creating a negative pressure environment inside the main housing. The air inlet is located closer to the main housing than the tail cover. A large amount of external air enters through the air inlet, first passing through the drive plate, cooling the drive plate and its components. Then, the gas, due to adsorption, enters the stator within the main housing, cooling both the stator and rotor, and finally exits through the exhaust port. This provides a strong cooling effect and prevents hot air backflow.

[0044] It should be noted that the above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. However, any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A wind-cooled permanent magnet brushless DC motor, comprising a housing, a stator, and a rotor, wherein a rotating shaft is provided inside the rotor, characterized in that, The stator is installed inside the housing, and the rotor is located inside the stator. The front end of the rotating shaft extends from the front end of the housing. A drive assembly is located inside the rear end of the housing. An impeller is installed on the rotating shaft and is located inside the front end of the housing. An air inlet is located on the rear side wall of the housing, and an air outlet is located on the front side wall of the housing. The stator has a gas flow channel. External air enters the housing through the air inlet and is discharged sequentially through the drive assembly, the gas flow channel, and the air outlet.

2. The air-cooled permanent magnet brushless DC motor according to claim 1, characterized in that, The housing includes a main housing and a rear housing. The rear housing is mounted on the rear end of the main housing. The drive assembly is installed inside the rear housing. The air inlet is located on the side wall of the rear housing, and the air outlet is located on the side wall of the main housing.

3. The air-cooled permanent magnet brushless DC motor according to claim 2, characterized in that, The front end of the main housing is equipped with a front cover, and the rear end of the main housing is equipped with a rear cover. The rear housing is connected to the rear cover, and a tail cover is installed on the rear housing. The tail cover, the front cover, and the rear cover are all provided with several through holes. The front end of the rotating shaft extends out from the front cover, and the rear end of the rotating shaft passes through the rear cover and the drive assembly.

4. The air-cooled permanent magnet brushless DC motor according to claim 1, characterized in that, The gas flow channels are numerous and distributed along the axial direction of the stator.

5. The air-cooled permanent magnet brushless DC motor according to claim 3, characterized in that, The drive assembly includes a drive board and components mounted on the drive board. A rotating shaft passes through the drive board, which is vertically connected to the rear end cover. The drive board has several vent holes that communicate with through holes on the rear end cover.

6. The air-cooled permanent magnet brushless DC motor according to claim 2, characterized in that, The air inlet and air outlet are provided with at least two, and at least two air inlets are evenly distributed on the side wall of the rear housing, and at least two air outlets are evenly distributed on the side wall of the main housing.

7. The air-cooled permanent magnet brushless DC motor according to claim 1, characterized in that, The rotor is fitted with a protective sleeve.

8. The air-cooled permanent magnet brushless DC motor according to claim 5, characterized in that, The air inlet on the side wall of the rear housing is directly opposite the components on the drive board, or the air inlet is located in the area behind the components on the drive board.

9. The air-cooled permanent magnet brushless DC motor according to claim 5, characterized in that, The drive plate has a groove on its side. After the drive plate is connected to the rear end cover, the groove communicates with the through hole on the rear end cover.

10. A cleaning device, characterized in that, The air-cooled permanent magnet brushless DC motor includes any one of claims 1-9.

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