Negative pressure fan based on high-speed brushless motor

Abstract

The negative pressure fan comprises a centrifugal impeller, a wind scooper and the high-speed brushless motor, the high-speed brushless motor is used for providing a high rotating speed, the centrifugal impeller and the wind scooper are matched to guide axial inlet air into radial outlet air, and under the driving of the high-speed brushless motor, the axial inlet air is guided into radial outlet air. The axial air inlet of the wind scooper has high negative pressure with one-way stability; according to the principle that the higher the air flow rate is, the lower the air pressure is, due to the fact that the axial air channel is communicated with the radial air outlet, when the high-speed brushless motor rotates continuously, the axial air channel in the heat dissipation shell will form the air flow continuously flowing towards the radial air outlet, and therefore the heat dissipation efficiency of the high-speed brushless motor is improved. And the airflow plays a role in cooling the high-speed brushless motor. The negative pressure fan is simple in structure, small in size and small in outer diameter, the suction force is higher by adopting the oblique flow type centrifugal impeller, and the requirement for a small-sized high-suction-force negative pressure fan is met.

Description

Technical Field

[0001] The invention relates to the field of negative pressure fans, and in particular to a negative pressure fan based on a high-speed brushless motor. Background Art

[0002] In some scenarios where miniaturized negative pressure fans are needed, such as small vacuum cleaners, sweeping robots, portable electric irons and other products, due to space constraints, the diameter of the installed negative pressure fans is small, resulting in weak suction of the negative pressure fans. Or due to miniaturization or structural improvements, it is necessary to reduce the diameter of the existing negative pressure fans while keeping the suction unchanged; and the reduction of the diameter of the negative pressure fans will affect the speed and heat dissipation.

[0003] In view of this, this application is filed. Summary of the invention

[0004] The present invention provides a negative pressure fan based on a high-speed brushless motor to solve at least one of the above technical problems.

[0005] To solve the above problems, as one aspect of the present invention, a negative pressure fan based on a high-speed brushless motor comprises a centrifugal impeller, comprising a substrate, and guide blades arranged on the substrate and utilizing centrifugal force to guide axial air intake to radial air outlet; an air guide cover, which is sleeved on the centrifugal impeller and is provided with an axial air inlet, and a radial air outlet is provided at a radial air outlet position adapted to the centrifugal impeller; a high-speed brushless motor, comprising a heat dissipation shell, and a brushless motor body located in the heat dissipation shell, the output shaft of the brushless motor body being connected to the substrate, the guide blades being located on a side away from the high-speed brushless motor, the heat dissipation shell being connected to the air guide cover, an axial air duct passing through the brushless motor body being provided in the heat dissipation shell, and the axial air duct being communicated with the radial air outlet.

[0006] Preferably, the centrifugal impeller is a diagonal flow centrifugal impeller, and the diameter of the centrifugal impeller is substantially the same as the outer diameter of the heat dissipation housing.

[0007] Preferably, the base plate is convex from the periphery to the middle portion toward the axial direction of the air inlet, and the guide blade is twisted from the air inlet end to the air outlet end.

[0008] Preferably, the upper edge of the guide blade has at least one height decreasing section from the air inlet end to the air outlet end in the shape of a blade height decreasing, the wind guide cover is provided with an arc-shaped turning section adapted to the height decreasing section, and the radial air outlet is provided with an air guide surface in roughly the same direction as the radial air outlet.

[0009] Preferably, the heat dissipation housing and the substrate are spaced apart, and the gap is 0.5-5 mm.

[0010] Preferably, the axial air duct is formed by a plurality of air guide plates in the heat dissipation housing, and the brushless motor body is supported by the plurality of air guide plates in the middle of the heat dissipation housing.

[0011] Preferably, the brushless motor body includes a stator mechanism, a rotor mechanism, a semicircular machine cover and a concave motor bracket, the stator mechanism and the rotor mechanism are installed in the concave motor bracket, the concave motor bracket and the semicircular machine cover form a cylindrical structure, and ventilation holes are provided at both ends of the cylindrical structure.

[0012] Preferably, the heat dissipation housing, the air guide plate, the semicircular machine cover and the concave motor bracket are all made of metal.

[0013] Preferably, one end of the air guide cover away from the axial air inlet is fixedly sleeved on the outside of the heat dissipation shell, and the radial air outlet extends to the position of the heat dissipation shell.

[0014] Preferably, a plurality of heat dissipation gaps corresponding to the positions of the heat dissipation shell are arranged at intervals along the circumferential direction on the inner side of the air guide cover, and the heat dissipation gaps and the heat dissipation shell form a heat dissipation channel, and the heat dissipation gaps are connected to the radial air outlets.

[0015] In view of the miniaturization and high negative pressure requirements of negative pressure fans, the present invention has developed a negative pressure fan based on a high-speed brushless motor. The high-speed brushless motor is used to provide a high rotation speed, and the centrifugal impeller and the air guide cover cooperate to guide the axial air inlet to the radial air outlet. Driven by the high-speed brushless motor at tens of thousands of revolutions per minute, the axial air inlet of the air guide cover has a high negative pressure with unidirectional stability; and the high negative pressure forms a huge high-speed airflow at the radial air outlet. According to the principle that the higher the gas flow rate, the lower the air pressure, since the axial air duct is connected to the radial air outlet, when the high-speed brushless motor continues to rotate, the axial air duct in the heat dissipation housing will form an airflow that continuously flows toward the radial air outlet, and this airflow has the effect of cooling the high-speed brushless motor.

[0016] Furthermore, the negative pressure fan has a simple structure and adopts an oblique flow centrifugal impeller to make the suction stronger. The diameter of the centrifugal impeller is set to be roughly the same as the outer diameter of the heat dissipation shell, thereby further miniaturizing the outer diameter of the entire negative pressure fan and meeting the scenario that requires a miniaturized negative pressure fan. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 1 is a schematic diagram of the structure of a negative pressure fan based on a high-speed brushless motor according to an embodiment of the present invention;

[0018] Figure 2 yes Figure 1 Schematic diagram of the explosion structure;

[0019] Figure 3 yes Figure 1Schematic diagram of the vertical section structure;

[0020] Figure 4 yes Figure 3 Schematic diagram of the cross-sectional structure at AA;

[0021] Figure 5 yes Figure 1 A schematic diagram of the structure of a hidden air guide cover;

[0022] Figure 6 yes Figure 1 A schematic diagram of the structure of a hidden heat dissipation housing;

[0023] Figure 7 yes Figure 1 A schematic diagram of the structure of a centrifugal impeller;

[0024] Figure 8 yes Figure 1 Schematic diagram of the structure of the air guide cover.

[0025] Reference numerals:

[0026] 1. Centrifugal impeller; 11. Base plate; 12. Guide blades; 2. Air guide cover; 21. Axial air inlet; 22. Radial air outlet; 221. Air guide surface; 23. Arc-shaped turning section; 24. Heat dissipation gap; 3. High-speed brushless motor; 31. Heat dissipation housing; 311. Air guide plate; 32. Brushless motor body; 321. Output shaft. DETAILED DESCRIPTION

[0027] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention. Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the invention claimed for protection, but merely represents the selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0028] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicating orientations or positional relationships are based on the orientations or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In the description of the present invention, unless otherwise specified, "plurality" means two or more.

[0029] The specific embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0030] Please refer to Figures 1 to 8 A negative pressure fan based on a high-speed brushless motor 3 includes a centrifugal impeller 1, an air guide cover 2 and a high-speed brushless motor 3.

[0031] The centrifugal impeller 1 includes a base plate 11 and guide blades 12 arranged on the base plate 11 for guiding the axial air inlet to the radial air outlet by using the centrifugal force. The guide blades 12 are arranged on one side surface of the base plate 11, and the base plate 11 is circular.

[0032] The air guide cover 2 is sleeved on the centrifugal impeller 1 and is provided with an axial air inlet 21 , and is adapted to be provided with a radial air outlet 22 at a radial air outlet position of the centrifugal impeller 1 ; there are a plurality of radial air outlets 22 , which are arranged at intervals.

[0033] The high-speed brushless motor 3 includes a heat dissipation shell 31 and a brushless motor body 32 located in the heat dissipation shell 31, the output shaft 321 of the brushless motor body 32 is connected to the substrate 11, the guide blades 12 are located on the side away from the high-speed brushless motor 3, the heat dissipation shell 31 is connected to the wind guide cover 2, and an axial air duct passing through the brushless motor body 32 is provided in the heat dissipation shell 31, and the axial air duct is communicated with the radial air outlet 22.

[0034] The highest speed of the high-speed brushless motor 3 can reach tens of thousands of revolutions per minute, and the normal state can be maintained at tens of thousands of revolutions per minute. Driven by the high-speed brushless motor 3 with tens of thousands of revolutions per minute, please refer to Figure 3The gas flow direction is indicated by the small arrow, and the axial air inlet 21 of the air guide cover 2 has a high negative pressure with unidirectional stability; and the high negative pressure forms a huge high-speed airflow at the radial air outlet 22. According to the principle that the higher the gas flow rate, the lower the air pressure, since the axial air duct is connected with the radial air outlet 22, when the high-speed brushless motor 3 continues to rotate, the axial air duct in the heat dissipation housing 31 will form an airflow that continuously flows toward the radial air outlet 22 under the impetus of the normal atmospheric pressure at the other end, and this airflow has the effect of dissipating the heat of the high-speed brushless motor 3.

[0035] Furthermore, the centrifugal impeller 1 is a diagonal flow centrifugal impeller 1, and the diameter of the centrifugal impeller 1 is substantially the same as the outer diameter of the heat dissipation housing 31. The negative pressure fan has a simple structure, and the diagonal flow centrifugal impeller 1 is used to make the suction stronger. The diameter of the centrifugal impeller 1 is set to be substantially the same as the outer diameter of the heat dissipation housing 31, thereby further miniaturizing the outer diameter of the entire negative pressure fan, meeting the scene where a miniaturized negative pressure fan is required.

[0036] Preferably, the base plate 11 of the diagonal flow centrifugal impeller 1 protrudes from the periphery to the middle toward the axial air inlet 21, and the guide blades 12 are twisted from the air inlet end to the air outlet end, so that when rotating at high speed, rotating wind is formed to obtain a greater centrifugal driving force on the gas.

[0037] Among them, the upper edge of the guide blade 12 has at least one height decreasing section from the air inlet end to the air outlet end in the shape of a blade decreasing height, and the air guide cover 2 is provided with an arc-shaped turning section 23 adapted to the height decreasing section, so that the gas enters from the axial air inlet 21 and accelerates to flow along the radial direction in the channel formed by multiple guide blades 12, and with the cooperation of the arc-shaped turning section 23 of the air guide cover 2, the turning is smoother and the loss of dynamic pressure is reduced, so that the negative pressure efficiency is higher, wherein, under the condition of a negative pressure fan diameter of 32.5mm, the fully closed pressure can reach 8.0Kpa; in other embodiments, the diameter range of the negative pressure fan diameter is 25 to 40mm.

[0038] Please refer to Figure 4 and Figure 8 The radial air outlet 22 is provided with an air guide surface 221 which is roughly in the same direction as the radial air outlet, so that the rotating wind can maintain the highest speed and flow out along the air guide surface 221, ensuring the high-speed flow of gas in the radial air outlet 22, thereby forming a negative pressure suction force facing the axial air duct in the heat dissipation shell 31, thereby achieving the effect of heat dissipation of the brushless motor body 32.

[0039] Preferably, the number of the guide blades 12 is 6 to 9, and the number of the radial air outlets 22 is 12 to 18 along the circumference of the air guide cover 2. In this embodiment, the number of the guide blades 12 is 7, and the number of the radial air outlets 22 is 14 along the circumference of the air guide cover 2.

[0040] In order to make the gas flow in the axial air duct better when the centrifugal impeller 1 rotates, it is necessary to optimize the connection between the axial air duct and the radial air outlet 22. In this embodiment, the heat dissipation shell 31 and the substrate 11 are arranged with a gap, and the preferred gap is 0.5 to 5 mm. Within this gap range, the gas flow driven by the air pressure difference can be fully utilized for heat dissipation.

[0041] In other embodiments, the heat dissipation housing 31 may be provided with a ventilation gap relative to the radial air outlet 22 , so that the axial air duct is connected to the radial air outlet 22 .

[0042] In other embodiments, the axial air duct may be a heat dissipation housing that fixes the motor body through a rod-shaped structure, a block-shaped structure, or other structures, so as not to block the axial flow of gas.

[0043] In this embodiment, the axial air duct is formed by a plurality of air guide plates 311 in the heat dissipation housing 31, and the brushless motor body 32 is supported by the plurality of air guide plates 311 in the middle of the heat dissipation housing 31. Furthermore, the air guide plates 311 can be tilted in a certain direction toward the circumferential direction, and the tilting direction is adapted to the air guide surface 221 of the radial air outlet 22.

[0044] There are many structures of the brushless motor body 32. In order to further improve the heat dissipation effect, in this embodiment, the brushless motor body 32 includes a stator mechanism, a rotor mechanism, a semicircular cover and a concave motor bracket. The stator mechanism and the rotor mechanism are installed in the concave motor bracket. The concave motor bracket and the semicircular cover form a cylindrical structure, and vents are provided at both ends of the cylindrical structure. For details, you can also refer to the structure of a high-speed hair dryer motor in Chinese Patent Publication No. CN218586993U.

[0045] The heat dissipation housing 31, the air guide plate 311, the semicircular cover and the concave motor bracket are all made of metal, so that the heat dissipation effect is better. The metal material can be aluminum alloy, or aluminum, copper, copper alloy and other metals with good heat dissipation effect.

[0046] Please refer to Figure 1 and Figure 2 The end of the air guide cover 2 away from the axial air inlet 21 is fixedly sleeved on the outside of the heat dissipation housing 31, and its connection structure is simple and easy to assemble. The radial air outlet 22 extends to the position of the heat dissipation housing 31, so that the axial air duct can be directly connected to the radial air outlet 22 through the gap between the heat dissipation housing and the substrate 11, reducing the obstruction of gas flow and improving the heat dissipation effect.

[0047] For further information, please refer to Figure 1 and Figure 8A plurality of heat dissipation notches 24 corresponding to the position of the heat dissipation shell 31 are arranged at intervals along the circumferential direction on the inner side of the air guide cover 2, and the heat dissipation notches 24 and the heat dissipation shell 31 form a heat dissipation channel, and the heat dissipation notches 24 are connected to the radial air outlet 22. The heat dissipation notches 24 can effectively improve the heat dissipation effect of the heat dissipation shell 31. The principle is that there is a high-speed airflow at the position of the radial air outlet 22 with low air pressure, and the other end of the heat dissipation notch 24 is at atmospheric pressure. Therefore, the heat dissipation channel forms an airflow flowing toward the radial air outlet 22 under the action of atmospheric pressure, thereby improving the heat dissipation effect of the heat dissipation shell 31.

[0048] Furthermore, in other embodiments, a centrifugal guide groove or a centrifugal guide ridge is provided on the surface of one side of the substrate 11 close to the heat dissipation shell 31, and the average height of the guide blade 12 is defined as H. The height of the centrifugal guide groove or the centrifugal guide ridge is 1 / 20H to 1 / 10H. The centrifugal guide groove or the centrifugal guide ridge can play the same role as the guide blade 12 in guiding the axial air intake to radial air outlet by using centrifugal force. However, since its height is much smaller than the guide blade 12, its energy consumption is also much smaller than the guide blade 12. However, it can provide sufficient negative pressure suction to inhale gas at high speed from the other end of the axial air duct, thereby improving the heat dissipation effect of the brushless motor body 32.

[0049] The above are only preferred implementations of the present invention. The protection scope of the present invention is not limited to the above embodiments. All technical solutions under the concept of the present invention belong to the protection scope of the present invention.

Claims

1. A negative pressure fan based on a high-speed brushless motor, characterized in that: include, The centrifugal impeller comprises a base plate and guide blades arranged on the base plate and guiding the axial air inlet to the radial air outlet by utilizing the centrifugal force; An air guide cover is sleeved on the centrifugal impeller and is provided with an axial air inlet, and is adapted to be provided with a radial air outlet at a radial air outlet position of the centrifugal impeller; A high-speed brushless motor comprises a heat dissipation shell and a brushless motor body located in the heat dissipation shell, wherein the output shaft of the brushless motor body is connected to the substrate, the guide blades are located on a side away from the high-speed brushless motor, the heat dissipation shell is connected to the wind guide cover, an axial air duct passing through the brushless motor body is provided in the heat dissipation shell, and the axial air duct is communicated with the radial air outlet.

2. The negative pressure fan based on a high-speed brushless motor according to claim 1, characterized in that: The centrifugal impeller is a diagonal flow centrifugal impeller, and the diameter of the centrifugal impeller is substantially the same as the outer diameter of the heat dissipation housing.

3. The negative pressure fan based on a high-speed brushless motor according to claim 2, characterized in that: The base plate protrudes from the periphery to the middle portion toward the axial direction of the air inlet, and the guide blade is twisted from the air inlet end to the air outlet end.

4. The negative pressure fan based on a high-speed brushless motor according to claim 3 is characterized in that: The upper edge of the guide blade has at least one height decreasing section from the air inlet end to the air outlet end, and the wind guide cover is provided with an arc-shaped turning section adapted to the height decreasing section, and the radial air outlet is provided with an air guide surface in roughly the same direction as the radial air outlet.

5. The negative pressure fan based on a high-speed brushless motor according to claim 1, characterized in that: The heat dissipation housing and the substrate are arranged with a gap, and the gap is 0.5-5 mm.

6. The negative pressure fan based on a high-speed brushless motor according to claim 5, characterized in that: The axial air duct is formed by a plurality of air guide plates in the heat dissipation housing, and the brushless motor body is supported by the plurality of air guide plates in the middle of the heat dissipation housing.

7. The negative pressure fan based on a high-speed brushless motor according to claim 6, characterized in that: The brushless motor body comprises a stator mechanism, a rotor mechanism, a semicircular machine cover and a concave motor bracket. The stator mechanism and the rotor mechanism are installed in the concave motor bracket. The concave motor bracket and the semicircular machine cover form a cylindrical structure. Ventilation holes are provided at both ends of the cylindrical structure.

8. The negative pressure fan based on a high-speed brushless motor according to claim 7, characterized in that: The heat dissipation housing, the air guide plate, the semicircular machine cover and the concave motor bracket are all made of metal.

9. The negative pressure fan based on a high-speed brushless motor according to claim 5, characterized in that: One end of the air guide cover away from the axial air inlet is fixedly sleeved on the outside of the heat dissipation shell, and the radial air outlet extends to the position of the heat dissipation shell.

10. The negative pressure fan based on a high-speed brushless motor according to claim 9, characterized in that: A plurality of heat dissipation notches corresponding to the positions of the heat dissipation shell are arranged at intervals along the circumferential direction on the inner side of the air guide cover, and the heat dissipation notches and the heat dissipation shell form a heat dissipation channel, and the heat dissipation notches are connected to the radial air outlet.

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