Brushless motor and its impeller

Abstract

The present invention relates to a brushless motor and its impeller, the brushless motor comprises a housing provided with a stator assembly fixing block, a stator assembly, a rotor assembly, a rear cover, a front bearing, a rear bearing and an air duct system component, the air duct system component comprises an air hood and an impeller; the air hood comprises a rear end portion and a front end portion provided with a front bearing fixing block; the front end of the stator assembly is fixed on the first central through hole of the stator assembly fixing block of the housing; the rear bearing is arranged in the rear bearing chamber of the rear cover, and the rear cover is fixed to the rear end of the housing; the front bearing is arranged in the front bearing chamber of the front bearing fixing block of the air hood, and the rear end of the air hood is fixed to the front end of the housing; the rear end of the rotating shaft of the rotor assembly is inserted from the inner hole of the rear bearing, the front end of the rotating shaft passes through the inner hole of the front bearing, and the impeller is fixed at the front end of the rotating shaft and is located in the first truncated cone-shaped cavity at the front end of the air hood. The brushless motor of the present invention has the advantages of high speed, large suction, small size, light weight, low noise and high efficiency.

Description

Technical field

[0002] The present invention relates to a motor, in particular to a small or micro motor, and more particularly to a small or micro brushless motor, such as a brushless motor used in a vacuum cleaner. [Background Technology]

[0004] A brushless motor in the prior art, such as a brushless motor used in a vacuum cleaner, sometimes simply called a vacuum cleaner motor, has the following shortcomings:

[0005] First, due to the limitations of the air duct system structure of the existing vacuum cleaner motor, the air intake mode of the existing vacuum cleaner is to completely isolate the dust at the outer end of the motor air inlet. The air inlet must use a very dense filter screen and filter element to isolate the dust, which increases the airflow obstruction and reduces the suction power of the motor.

[0006] Second, existing vacuum cleaner motors use centrifugal impellers, which are relatively large. The first blades on the impeller are riveted, making the entire impeller less robust. Due to limitations such as the centrifugal impeller structure, the motor's maximum speed is typically limited to 60,000 to 80,000 rpm (revolutions per minute). Furthermore, the operating efficiency range is relatively narrow, significantly limiting operating performance. These motors generally suffer from shortcomings such as low suction power, large size, heavy weight, high noise, and low efficiency.

[0007] 3. The clearance between the impeller and other components of the existing vacuum cleaner motor is large. When the gap is large, the airflow collides with each other, which will generate noise, resulting in a large airflow loss, making it impossible for the entire motor to achieve a better efficiency. Moreover, when the airflow flows out of the root of the impeller at ultra-high speed, the airflow will run around and turbulence will occur. These turbulent flows collide with the surrounding materials, which will produce abnormal noise, affecting the normal operation of the airflow and other problems. [Summary of the invention]

[0009] The technical problem to be solved by the present invention is to avoid the above-mentioned shortcomings of the prior art and provide a brushless motor and its impeller, which have the advantages of reasonable structure, high speed, strong suction, small size, light weight, low noise and high efficiency.

[0010] The technical solution adopted by the present invention to solve the technical problem is:

[0011] A brushless motor is provided, which can be used in products such as vacuum cleaners, and includes a housing with two open ends and a hollow interior, a stator assembly, a rotor assembly, a rear cover with a rear bearing chamber, a front bearing, and a rear bearing; the stator assembly includes a stator core and stator windings arranged in each stator slot of the stator core; the rotor assembly includes a rotating shaft and a permanent magnet component fixed to the rotating shaft; the brushless motor also includes an air duct system component, the air duct system component includes a wind shield with two open ends and a hollow interior and an impeller; the wind shield includes a rear end connected and fixed to the front end of the housing and a hollow interior connected to the rear end and shaped like a horn The front end portion of the fan is shaped, the diameter of the joint where the rear end portion and the front end portion are connected is smaller than the diameter of the open end of the rear end portion and the front end portion, and the radial size gradually increases from the joint portion to the open end of the front end portion so that the front end portion is formed into a trumpet shape, and a front bearing fixing block is provided in the rear end portion of the fan cover, and the front bearing fixing block is fixed to the inner wall of the rear end portion of the fan cover by at least two first ribs, and a first air duct for air flow is formed between two adjacent first ribs, and the front bearing fixing block is provided with a front bearing chamber that can accommodate the front bearing, and the front end portion is provided with a first circular trumpet-shaped member that cooperates with the impeller The impeller has an opening at one end and is horn-shaped, comprising a horn-shaped wheel disc, a wheel disc bottom connected to the wheel disc, and a plurality of first blades, the radial size of which gradually increases from the wheel disc bottom to the open end of the wheel disc to form a horn shape, so that the inner surface of the wheel disc is a horn-shaped second truncated cone-shaped cavity, a plurality of first blades are evenly arranged on the outer surface of the wheel disc to form an integrated structure with the outer surface of the wheel disc, and a second air duct for air flow is formed between two adjacent first blades, and a central through hole is provided at the bottom of the wheel disc to match the front end of the rotating shaft of the rotor assembly; a stator assembly is fixed in the housing. The stator assembly fixing block is fixed to the inner wall of the shell by at least two second ribs, and a third air duct for airflow is formed between two adjacent second ribs. The length of the stator assembly fixing block is less than the length of the shell, and the stator assembly fixing block is provided with a first central through hole capable of fixing the stator assembly; the front end of the stator assembly is fixed to the first central through hole of the stator assembly fixing block of the shell; the rear bearing is arranged in the rear bearing chamber of the rear cover, and the rear cover is fixed to the rear end of the shell; the front bearing is arranged in the front bearing chamber of the bearing fixing block in front of the wind shield, and the rear end of the wind shield is fixed to the front end of the shell;The rear end of the rotor assembly's rotating shaft is inserted through the inner hole of the rear bearing, and the front end of the rotor assembly's rotating shaft passes through the inner hole of the front bearing. The permanent magnet component of the rotor assembly is located within the inner cavity of the stator core of the stator assembly. The impeller is fixed to the front end of the rotating shaft and is located within the first frustoconical cavity at the front end of the wind shield. The bottom of the impeller's wheel disc is adjacent to the bottom of the first frustoconical cavity at the front end of the wind shield. The outer end surfaces of each first blade on the outer surface of the impeller's wheel disc and the inner surface of the first frustoconical cavity at the front end of the wind shield form an air duct gap.

[0012] The height of each first blade gradually decreases from the air inlet end to the air outlet end.

[0013] The thickness of each first blade gradually increases from the air inlet end to the air outlet end.

[0014] The first blades are evenly arranged on the outer surface of the wheel disc in an inclined manner along the rotation direction of the brushless motor.

[0015] Both side surfaces of each first blade at the contact point with the outer surface of the wheel disc are arc-shaped contact surfaces.

[0016] The outer surface of the rear end of the shell is provided with at least two windows communicating with the inner surface.

[0017] The rear cover is also open at both ends and hollow inside. The rear bearing chamber is located on the rear bearing chamber fixing block, which is fixed to the inner wall of the rear cover by at least two third ribs. A fourth air duct for airflow is formed between two adjacent third ribs.

[0018] The air duct system component also includes a stator impeller, which includes an outer cylindrical portion with openings at both ends and a hollow interior, an inner cylindrical portion with openings at both ends and a central cylindrical portion; the inner cylindrical portion is fixed to the inner wall of the outer cylindrical portion by a plurality of second blades, and a fifth air duct for air flow is formed between two adjacent second blades; the central cylindrical portion is fixed to the inner wall of the inner cylindrical portion by at least two fourth ribs; the outer cylindrical portion of the stator impeller is fixed to the front end portion of the wind cover; the first air duct and the first conical cavity of the wind cover, together with the first blades and the second air duct of the impeller, and the fifth air duct of the stator impeller, constitute an air duct for air flow flowing in the air duct system component.

[0019] An impeller is also provided for use on a motor, in particular for a brushless motor. One end of the impeller is open and trumpet-shaped, comprising a trumpet-shaped wheel disc, a wheel disc bottom connected to the wheel disc, and a plurality of first blades. The radial size gradually increases from the wheel disc bottom to the open end of the wheel disc to form a trumpet shape, so that the inner surface of the wheel disc is a trumpet-shaped second frustum-shaped cavity. The plurality of first blades are evenly arranged on the outer surface of the wheel disc to form an integrated structure with the outer surface of the wheel disc. A central through hole is provided at the bottom of the wheel disc.

[0020] Compared with the prior art, the brushless motor and its impeller of the present invention have the following beneficial effects:

[0021] First, the present invention sets the impeller into a special structure of oblique flow, and the structure of the wind cover is also changed accordingly, so that the entire brushless motor is small in size and light in weight, and the air duct system of the brushless motor is changed. The air flow intake mode is different from that of the motor in the prior art. The structure of the brushless motor of the present invention can adopt a segmented dust isolation method. The vacuum cleaner product equipped with the brushless motor of the present invention first isolates large particles of dust outside the brushless motor of the present invention, allowing fine particles of dust to enter the brushless motor of the present invention, and then isolates them again at the air outlet end of the brushless motor of the present invention, thereby changing the air intake system of the brushless motor, improving the working efficiency of the brushless motor, and making full use of the suction force of the brushless motor. With the structure of the brushless motor and its impeller of the present invention, the maximum speed of the motor can reach 110,000 rpm to 130,000 rpm, which is much higher than the maximum speed of 60,000 rpm to 80,000 rpm of the vacuum cleaner motor in the prior art.

[0022] Second, the impeller of the present invention further improves the uniformly inclined distribution of the first blades on the outer surface of the impeller disc and adjusts the thickness and height distribution of the first blades, thereby improving the airflow separation state in the air inlet area of ​​the impeller, reducing airflow loss and lowering noise;

[0023] Third, the present invention sets a fixed impeller on the impeller and the wind cover at the air outlet position, and designs a plurality of second blades in the fixed impeller. The second blades are designed to be arc-shaped and evenly inclined on the outer surface of the inner cylindrical part and the inner wall of the outer cylindrical part of the fixed impeller, thereby guiding the airflow and reducing a series of defects caused by the collision of airflows.

[0024] 4. The structure of the brushless motor and its impeller of the present invention makes the air flow channels of the present invention different. A part of the air flow enters the outer shell from the fourth air ducts of the rear cover, and then enters the air duct system component after passing through the third air ducts in the outer shell; another part of the air flow enters the outer shell from the windows of the outer shell, and then enters the air duct system component after passing through the third air ducts in the outer shell; the air flow entering the air duct system component flows into the second air duct of the impeller through the first air duct of the wind cover and the first frustum-shaped cavity, and then flows out from the fifth air duct of the stator impeller.

[0025] In summary, the brushless motor and its impeller of the present invention have the advantages of reasonable structure, high speed, strong suction, small size, light weight, low noise and high efficiency.

Brief Description of the Drawings

[0027] Figure 1 1 is an axonometric projection diagram of the brushless motor of the present invention;

[0028] Figure 2 Is a schematic diagram of the axonometric projection of the brushless motor in another direction;

[0029] Figure 3 1 is a schematic cross-sectional view of an orthographic projection of the brushless motor, wherein each dotted line in the figure represents an airflow path, and the arrows on the dotted lines represent the direction of the airflow;

[0030] Figure 4 is a schematic diagram of an axonometric projection of the brushless motor after decomposition;

[0031] Figure 5 is a schematic diagram of an axonometric projection of the housing of the brushless motor;

[0032] Figure 6 is a schematic cross-sectional view of the orthographic projection of the housing;

[0033] Figure 7 is an axonometric projection diagram of the stator core of the brushless motor;

[0034] Figure 8 is an axonometric projection diagram of the air duct system components of the brushless motor;

[0035] Figure 9 This is a schematic diagram of the axonometric projection of the duct system components in another direction

[0036] Figure 10 : is a schematic orthographic front cross-sectional view of the air duct system component, in which each dotted line represents the route of air flow, and the arrow on the dotted line represents the direction of air flow;

[0037] Figure 11 is a schematic diagram of an axonometric projection of the decomposed components of the air duct system;

[0038] Figure 12 It is one of the axonometric projection diagrams of the impeller of the air duct system component;

[0039] Figure 13 is the second axonometric projection diagram of the impeller;

[0040] Figure 14 is a third axonometric projection diagram of the impeller;

[0041] Figure 15 is a schematic top view of the orthographic projection of the impeller;

[0042] Figure 16 is a schematic diagram of an orthographic main view of the impeller;

[0043] Figure 17 is a schematic rear view of the orthographic projection of the impeller;

[0044] Figure 18 yes Figure 17 A schematic cross-sectional view of AA is shown;

[0045] Figure 19 is an axonometric projection diagram of the stator impeller of the air duct system component;

[0046] Figure 20 is a schematic diagram of an axonometric projection of the stator impeller in another direction;

[0047] Figure 21 is a schematic diagram of an orthographic projection of the stator impeller;

[0048] Figure 22 yes Figure 21 A schematic cross-sectional view of BB shown;

[0049] Figure 23 yes Figure 21 A schematic cross-sectional view of the CC shown;

[0050] Figure 24 is an axonometric projection diagram of the air hood of the air duct system component;

[0051] Figure 25 It is a schematic diagram of the axonometric projection of the wind hood in the other direction. [Specific implementation method]

[0053] The present invention will be further described in detail below with reference to the accompanying drawings.

[0054] See also Figures 1 to 25A brushless motor can be used in products such as vacuum cleaners, including a housing 10 with two open ends and a hollow interior, a stator assembly 20, a rotor assembly 30, a rear cover 40 with a rear bearing chamber 45, a front bearing 51, and a rear bearing 52; the stator assembly 20 includes a stator core 21 and stator windings (not shown) arranged in each stator slot 211 of the stator core 21. For example, the applicant has a brushless motor using a stator core 21 with three stator slots 211; the rotor assembly 30 includes a rotating shaft 31 and a permanent magnet component 32 fixed to the rotating shaft 31; the brushless motor also includes an air duct system component 60, which includes a wind hood 61 with two open ends and a hollow interior and an impeller 6 2; The wind shield 61 includes a rear end portion 611 connected and fixed to the front end of the housing 10 and a front end portion 612 connected to the rear end portion 611 and having a hollow interior and a trumpet shape. The diameter of the joint 613 where the rear end portion 611 and the front end portion 612 are connected is smaller than the diameter of the open ends of the rear end portion 611 and the front end portion 612. The radial size gradually increases from the joint 613 to the open end of the front end portion 612, so that the front end portion 612 is formed into a trumpet shape. A front bearing fixing block 6111 is provided in the rear end portion 611 of the wind shield 61. The front bearing fixing block 6111 is fixed to the inner wall of the rear end portion 611 of the wind shield 61 by at least two first ribs 6112. Adjacent A first air duct 6113 for air flow is formed between the two first ribs 6112. There are four first ribs 6112 in the present invention, and correspondingly there are four first air ducts 6113. The front bearing fixing block 6111 is provided with a front bearing chamber 61111 that can accommodate the front bearing 51. The front end portion 612 is provided with a first truncated cone-shaped cavity 6121 that is matched with the impeller 62 and is in the shape of a trumpet. One end of the impeller 62 is open and trumpet-shaped, including a trumpet-shaped wheel disc 621, a wheel disc bottom 622 connected to the wheel disc 621, and a plurality of first blades 623. The radial size gradually increases from the wheel disc bottom 622 to the open end of the wheel disc 621 to form a trumpet shape, so that the wheel disc 621 The inner surface of the second truncated cone-shaped cavity 6211 is horn-shaped. A plurality of first blades 623 are evenly arranged on the outer surface of the wheel disc 621 to form an integral structure with the outer surface of the wheel disc 621. A second air duct 624 for airflow is formed between two adjacent first blades 623. The present invention has nine first blades 623, and correspondingly, there are nine second air ducts 624. The first air duct 6113 and the first truncated cone-shaped cavity 6121 of the wind shield 61, together with the first blades 623 and the second air duct 624 of the impeller 62, constitute an air duct for airflow within the air duct system component 60. The bottom 622 of the wheel disc is provided with a central through hole 6221 that cooperates with the front end of the rotating shaft 31 of the rotor assembly 30.A stator assembly fixing block 11 is provided in the housing 10, and the stator assembly fixing block 11 is fixed to the inner wall of the housing 10 by at least two second ribs 12, and a third air duct 13 for air flow is formed between two adjacent second ribs 12. There are four second ribs 12 in the present invention, and correspondingly there are four third air ducts 13. The length of the stator assembly fixing block 11 is less than the length of the housing 10, and the stator assembly fixing block 11 is provided with a first central through hole 111 that can fix the stator assembly 20; the front end of the stator assembly 20 is fixed to the first central through hole 111 of the stator assembly fixing block 11 of the housing 10; the rear bearing 52 is provided in the rear bearing chamber 45 of the rear cover 40, and the rear cover 40 is fixed to the rear end of the housing 10; the front bearing 51 is provided in the front bearing chamber 61111 of the bearing fixing block 6111 in front of the wind hood 61, and the rear end portion 611 of the wind hood 61 is fixed to the The front end of the housing 10; the rear end of the rotating shaft 31 of the rotor assembly 30 is inserted into the inner hole of the rear bearing 52, and the front end of the rotating shaft 31 of the rotor assembly 30 passes through the inner hole of the front bearing 51; the permanent magnet component 32 of the rotor assembly 30 is located in the inner cavity of the stator core 21 of the stator assembly 20; the central through hole 6221 of the wheel disc bottom 622 of the impeller 62 is fixed to the front end of the rotating shaft 31, so that the impeller 62 is fixed to the front end of the rotating shaft 31 and is located in the first conical cavity 6121 of the front end portion 612 of the wind cover 61, the wheel disc bottom 622 of the impeller 62 is close to the bottom of the first conical cavity 6121 of the front end portion 612 of the wind cover 61, and the outer end surface of each first blade 623 on the outer surface of the wheel disc 621 of the impeller 62 and the inner surface of the first conical cavity 6121 of the front end portion 612 of the wind cover 61 form an air duct gap. The trumpet-shaped structure described in the present invention can also be described as a truncated cone-shaped structure, which is hollow inside and has a certain wall thickness.

[0055] See also Figures 12 to 18 In order to facilitate smooth airflow and easy airflow entry, the height of each first blade 623 gradually decreases from the air inlet end to the air outlet end. Figure 3It can be seen from the figure that the air flow flows from the bottom 622 of the impeller 62 to the open end of the impeller 62's disc 621. Therefore, the end of each first blade 623 of the impeller 62 of the present invention close to the bottom 622 of the disc is the air inlet end, and the end away from the bottom 622 of the disc, that is, the open end of the impeller 621 of the impeller 62 is the air outlet end. Therefore, it can also be said that the height of each first blade 623 gradually decreases from the end close to the bottom 622 of the disc toward the open end of the disc 621. Specifically, the height H1 of each first blade 623 at the air inlet end is the largest, and the height H2 of each first blade 623 at the air outlet end is the smallest. For example, the applicant has an impeller 62 in which the height H1 of each first blade 623 at the air inlet end is 5.0 mm, while the height H2 of each first blade 623 at the air outlet end is only 3.5 mm. In this way, the airflow is easily gathered when entering, and is easily dispersed when leaving.

[0056] See also Figures 12 to 18 The thickness of each first blade 623 gradually increases from the air inlet end to the air outlet end. Alternatively, the thickness of each first blade 623 gradually increases from the end closest to the disc bottom 622 toward the open end of the disc 621. Specifically, the thickness T1 of each first blade 623 is smallest at the air inlet end, while the thickness T2 of each first blade 623 is largest at the air outlet end. For example, the applicant has an impeller 62 in which the thickness T1 of each first blade 623 at the air inlet end is only 0.1 mm, while the thickness T2 of each first blade 623 at the air outlet end reaches 0.9 mm. The thickness of each first blade 623 at the air inlet end is relatively thin, which makes it easy for airflow to enter. However, when the motor rotates at high speed, the airflow collides with each other during circulation, and thin blades will cause defects such as blade deformation and relatively high noise. Therefore, the present invention deliberately increases the thickness of each first blade 623 from the air inlet end to the air outlet end. This not only makes it easy for airflow to enter, but also increases the strength of each first blade 623, and the noise during airflow circulation will be reduced.

[0057] See also Figures 12 to 18 , each first blade 623 is evenly and evenly arranged on the outer surface of the wheel disc 621 in an inclined manner along the rotation direction of the brushless motor; when each first blade 623 is evenly and evenly arranged on the outer surface of the wheel disc 621 in an inclined manner along the rotation direction of the brushless motor, its inclination angle first increases and then decreases from the air outlet end, so that when the brushless motor rotates at high speed, the air flow can be easily inhaled, which can effectively reduce the fluid loss at the air inlet end.

[0058] See also Figures 12 to 17, the connection parts of the adjacent surfaces of the first blade 623 are designed to be arc-shaped, and the adjacent surfaces of the first blade 623 include the air inlet end surface 6231 of the first blade 623, the upper end surface 6232 of the first blade 623, the air outlet end surface 6233 of the first blade 623, the first side surface 6234 of the first blade 623 and the second side surface 6235 of the first blade 623, wherein the first side surface 6234 of the first blade 623 is the side surface at which the angle between the first blade 623 and the outer surface of the wheel disk 621 is less than 90 degrees, and the second side surface 6235 of the first blade 623 is the side surface at which the angle between the first blade 623 and the outer surface of the wheel disk 621 is greater than 90 degrees. The connection parts of the adjacent surfaces of the first blade 623 are designed to be arc-shaped, specifically, the connection between the air inlet end surface 6231 of the first blade 623 and the second side surface 6235 of the first blade 623, the air outlet end surface 6233 of the first blade 623 and the first side surface 6234 of the first blade 623. The connection and the connection between the air outlet end surface 6233 of the first blade 623 and the second side surface 6235 of the first blade 623 are all designed to be arc-shaped; the connection between the air inlet end surface 6231 of the first blade 623 and the upper end surface 6232 of the first blade 623, the connection between the air inlet end surface 6231 of the first blade 623 and the first side surface 6234 of the first blade 623, and the connection between the upper end surface 6232 of the first blade 623 and the first side surface 6234 of the first blade 623 are all designed to be arc-shaped; The connection between the upper end surface 6232 of the first blade 623 and the second side surface 6235 of the first blade 623, and the connection between the upper end surface 6232 of the first blade 623 and the air outlet end surface 6233 of the first blade 623 are not designed to be arc-shaped but directly form a straight edge; the advantage of this is that when the airflow passes through the second air duct 624 between the first blades 623, it will be discharged very smoothly, avoiding the first blades 623 from blocking the airflow when the impeller 62 rotates at high speed.

[0059] See also Figures 12 to 17 , the two side surfaces of each first blade 623 at the contact point with the outer surface of the wheel disc 621 are both arc-shaped contact surfaces 625, that is, the contact point between the first side surface 6234 of each first blade 623 and the outer surface of the wheel disc 621 and the contact point between the second side surface 6235 of each first blade 623 and the outer surface of the wheel disc 621 are both arc-shaped contact surfaces 625. In this way, the tail end of each first blade 623 is designed to be arc-shaped, which makes it easier for airflow to flow out and reduces the loss of airflow at the wake of each first blade 623.

[0060] See also Figure 1 、 Figure 2 、 Figure 4 and Figure 5The outer surface of the rear end of the shell 10 is provided with at least two windows 19 connected to the inner surface. The present invention has four windows 19 symmetrically opened on the outer surface of the rear end of the shell 10 connected to the inner surface.

[0061] See also Figure 1 and Figure 4 The rear cover 40 is also open at both ends and hollow inside. The rear bearing chamber 45 is located on the rear bearing chamber fixing block 41. The rear bearing chamber fixing block 41 is fixed to the inner wall of the rear cover 40 by at least two third ribs 42. A fourth air duct 43 for air flow is formed between two adjacent third ribs 42. There are four third ribs 42 in the present invention, and correspondingly there are four fourth air ducts 43.

[0062] See also Figures 1 to 4 、 Figures 8 to 12 and Figures 19 to 25 The air duct system component 60 also includes a fixed impeller 63, which includes an outer cylindrical portion 631 with openings at both ends and a hollow interior, an inner cylindrical portion 632 with openings at both ends and a hollow interior, and a central cylindrical portion 633; ​​the inner cylindrical portion 632 is fixed to the inner wall of the outer cylindrical portion 631 by a plurality of second blades 634, and the plurality of second blades 634 are arc-shaped and evenly inclined on the outer surface of the inner cylindrical portion 632 and the inner wall of the outer cylindrical portion 631, and a fifth air duct 635 for air flow is formed between two adjacent second blades 634. The second blades of the present invention There are ten 634s, and correspondingly there are ten fifth air ducts 635; the central cylindrical portion 633 is fixed to the inner wall of the inner cylindrical portion 632 by at least two fourth ribs 636; the outer cylindrical portion 631 of the stator 63 is fixed to the front end portion 612 of the wind cover 61; the first air duct 6113 and the first conical cavity 6121 of the wind cover 61, together with the first blades 623 and the second air duct 624 of the impeller 62, and the fifth air duct 635 of the stator 63 constitute an air duct for airflow to flow in the air duct system component 60.

[0063] In existing brushless motors, when the air flows out of the impeller root at ultra-high speed, the air will run around and turbulence will occur. These turbulent flows will collide with the surrounding materials, causing abnormal noise and affecting the normal operation of the airflow. Figures 1 to 4 、 Figures 8 to 12 and Figures 19 to 25 In order to overcome this defect, after many designs and tests, a fixed impeller 63 is specially installed on the impeller 62 and the wind cover 61 at the air outlet position. A plurality of second blades 634 are designed in the fixed impeller 63. The second blades 634 are designed to be arc-shaped and evenly inclined on the outer surface of the inner cylindrical part 632 of the fixed impeller 63 and the inner wall of the outer cylindrical part 631, so as to guide the airflow and reduce a series of defects caused by the collision of airflows.

[0064] See also Figure 3 and Figure 10 In the figure, the dashed lines represent airflow routes, with arrows on the dashed lines indicating airflow directions. A portion of the airflow enters the housing 10 through the fourth air ducts 43 of the rear cover 40, then passes through the third air ducts 13 within the housing 10 before entering the air duct system component 60. Another portion of the airflow enters the housing 10 through the windows 19 of the housing 10, then passes through the third air ducts 13 within the housing 10 before entering the air duct system component 60. The airflow entering the air duct system component 60 flows through the first air duct 6113 and the first frustoconical cavity 6121 of the air cover 61 into the second air duct 624 of the impeller 62, and then flows out through the fifth air duct 635 of the stator impeller 63.

[0065] See also Figure 5 and Figure 6 In fact, the housing 10, the stator assembly fixing block 11 and the rib 12 are the same part, but they can also be assembled from different parts.

[0066] See also Figure 3 and Figure 10 The rear cover 40 and its rear bearing chamber 45, the housing 10 and the first central through hole 111 of the stator assembly fixing block 11, the rear end portion 611 of the wind hood 61 and the front bearing chamber 61111 of the front bearing fixing block 6111, the front end portion 612 of the wind hood 61 and the impeller 62 have a common central axis.

[0067] See also Figures 1 to 6 The rear end surface of the rear cover 40 is also symmetrically provided with three axial bosses 44, which are mainly used to fix the control board 99 so that the control board 99 has a certain distance so that the air flow enters from the fourth air ducts 43 of the rear cover 40. Figures 1 to 3 Not shown. Figures 1 to 6 The rear port of the shell 10 is provided with a rear end inner stop 14 adapted to the outer stop 49 of the rear cover 40, and the front port of the shell 10 is provided with a front end inner stop 15 adapted to the outer stop 6119 of the rear end portion 611 of the wind hood 61; the first central through hole 111 of the stator assembly fixing block 11 of the shell 10 is divided into two stepped holes, wherein the first stepped hole 1111 is used to fix the stator core 21 of the stator assembly 20, and the second stepped hole 1112 is used to accommodate the end of the front bobbin (not marked) of the stator assembly 20, and the inner diameter of the first stepped hole 1111 is slightly larger than the inner diameter of the second stepped hole 1112.

[0068] See also Figure 3 、 Figures 10 to 14 and Figure 18In order to ensure the matching length between the impeller 62 and the rotating shaft 31, so that the impeller 62 is fixed more firmly and runs more smoothly, a central cylinder 6229 of a certain length is provided at the bottom 622 of the impeller disc of the impeller 62. The central through hole 6221 of the said bottom 622 of the disc passes through the central cylinder 6229. In order to save axial dimension, the central cylinder 6229 protrudes on both axial sides of the bottom 622 of the disc. In order to make the structure of the impeller 62 more solid, the bottom 622 of the disc further protrudes outward with a circle of disc bottom convex ring 6228. In order to save weight, a cavity 6227 is formed between the disc bottom convex ring 6228 and the central cylinder 6229. The impeller 62 of the present invention can be called a diagonal flow impeller, which is a great improvement over the centrifugal fan blades in the prior art. The various parts of the impeller 62 are integrally formed, and the material can be made of aluminum alloy or other materials such as a high-strength engineering plastic. The applicant has an impeller 62 made of aluminum alloy, because aluminum alloy material is relatively light and has high strength. In addition, the special structure of the impeller 62 of the present invention enables the impeller 62 of the present invention to maintain sufficient strength to withstand the relevant forces when the motor rotates at high speed. The overall structure of the impeller 62 of the present invention is very strong; and the impeller 62 of the present invention improves the uniformly inclined distribution of each first blade 623 on the outer surface of the wheel disc 621, and then adjusts the thickness and height distribution of each first blade 623, thereby improving the airflow separation state in the air inlet area of ​​the impeller 62, reducing airflow loss, and reducing noise. By adopting the impeller 62 with a special structure of the present invention, the air duct gap between the outer end surface of each first blade 623 on the outer surface of the wheel disk 621 of the impeller 62 and the inner surface of the first conical cavity 6121 of the front end portion 612 of the wind cover 61 can be reduced to 0.1 to 0.3 mm, so that the impeller 62 and the wind cover 61 can be matched with each other with high precision. For high-speed motors, it can effectively reduce airflow loss and improve noise problems. However, the air duct gap between the impeller and the wind cover in the prior art is relatively large, generally only reaching a minimum of 0.6 to 0.8 mm. When the air duct gap is large, the air flows collide with each other, which will generate noise, so the airflow loss is very large, and the motor product cannot achieve better efficiency.

[0069] By adopting the structure of the brushless motor and its impeller of the present invention, the maximum speed of the brushless motor can reach 110,000 rpm to 130,000 rpm, which is much higher than the maximum speed of 60,000 rpm to 80,000 rpm of the vacuum cleaner motor in the prior art; the brushless motor of the present invention adopts an oblique flow impeller, the air duct system components are different, and the air flow intake mode is different from the vacuum cleaner motor in the prior art. The structure of the brushless motor of the present invention can adopt a segmented dust isolation method. The vacuum cleaner product equipped with the brushless motor of the present invention first isolates large particles of dust outside the brushless motor of the present invention, and allows fine particles of dust to enter the inside of the brushless motor of the present invention, and isolates them again at the air outlet end of the brushless motor of the present invention, thereby changing the air intake system of the brushless motor, improving the working efficiency of the brushless motor, and making full use of the suction force of the brushless motor. The brushless motor of the present invention has the advantages of large suction force, small size, light weight, low noise and high efficiency.

[0070] The above-mentioned embodiments only express the preferred implementation modes of the present invention. The description thereof is relatively specific and detailed, but it should not be understood as limiting the patent scope of the present invention. It should be pointed out that a person skilled in the art can make a number of modifications and improvements without departing from the concept of the present invention, which all fall within the scope of protection of the present invention. Therefore, all equivalent changes and modifications made to the scope of the claims of the present invention should fall within the scope of coverage of the claims of the present invention.

Claims

1. A brushless motor, comprising a housing (10) with two ends open and an interior hollow, a stator assembly (20), a rotor assembly (30), a rear cover (40) provided with a rear bearing chamber (45), a front bearing (51) and a rear bearing (52); the stator assembly (20) comprising a stator core (21) and a stator winding arranged in each stator slot of the stator core (21); the rotor assembly (30) comprising a rotating shaft (31) and a permanent magnet component (32) fixed to the rotating shaft (31); Features: The air duct system component (60) is also included. The air duct system component (60) includes a wind shield (61) with two ends open and a hollow interior, and an impeller (62); the wind shield (61) includes a rear end portion (611) connected and fixed to the front end of the housing (10) and a front end portion (612) connected to the rear end portion (611) and having a hollow interior and a trumpet shape; the diameter of a joint portion (613) where the rear end portion (611) and the front end portion (612) are connected is greater than the diameter of the open ends of the rear end portion (611) and the front end portion (612). The diameters of the front end (612) and the front end (612) are small, and the radial dimension gradually increases from the joint (613) to the open end of the front end (612), so that the front end (612) is formed into a trumpet shape. A front bearing fixing block (6111) is provided in the rear end (611) of the wind shield (61). The front bearing fixing block (6111) is fixed to the inner wall of the rear end (611) of the wind shield (61) through at least two first ribs (6112). A first air duct (6113) for air flow is formed between two adjacent first ribs (6112). The front bearing fixing block (6111) is provided with a front bearing chamber (61111) capable of accommodating the front bearing (51); the front end portion (612) is provided with a first truncated cone-shaped cavity (6121) in a trumpet shape that matches the impeller (62); one end of the impeller (62) is open and trumpet-shaped, comprising a trumpet-shaped wheel disc (621), a wheel disc bottom (622) connected to the wheel disc (621), and a plurality of first blades (623), and a plurality of first blades (623) are provided in a radial direction from the wheel disc bottom (622) to the open end of the wheel disc (621). The size of the wheel disc (621) gradually increases to form a trumpet shape, so that the inner surface of the wheel disc (621) is a trumpet-shaped second truncated cone cavity (6211), a plurality of first blades (623) are evenly arranged on the outer surface of the wheel disc (621) to form an integral structure with the outer surface of the wheel disc (621), a second air duct (624) for airflow is formed between two adjacent first blades (623), and a central through hole (6221) is provided at the bottom (622) of the wheel disc to match the front end of the rotating shaft (31) of the rotor assembly (30); A stator assembly fixing block (11) is arranged in the housing (10); the stator assembly fixing block (11) is fixed to the inner wall of the housing (10) by at least two second ribs (12); a third air duct (13) for airflow is formed between two adjacent second ribs (12); the length of the stator assembly fixing block (11) is less than the length of the housing (10); and the stator assembly fixing block (11) is provided with a first central through hole (111) capable of fixing the stator assembly (20); The front end of the stator assembly (20) is fixed to the first central through hole (111) of the stator assembly fixing block (11) of the housing (10); the rear bearing (52) is arranged in the rear bearing chamber (45) of the rear cover (40), and the rear cover (40) is fixed to the rear end of the housing (10); the front bearing (51) is arranged in the front bearing chamber (61111) of the bearing fixing block (6111) in front of the wind shield (61), and the rear end (611) of the wind shield (61) is fixed to the front end of the housing (10); the rear end of the rotating shaft (31) of the rotor assembly (30) is inserted from the inner hole of the rear bearing (52), and the front end of the rotating shaft (31) of the rotor assembly (30) is inserted from the front bearing ( 51), the permanent magnet component (32) of the rotor assembly (30) is located in the inner cavity of the stator core (21) of the stator assembly (20), the impeller (62) is fixed to the front end of the rotating shaft (31) and is located in the first truncated cone-shaped cavity (6121) of the front end portion (612) of the wind shield (61), the bottom (622) of the impeller (62) is close to the bottom of the first truncated cone-shaped cavity (6121) of the front end portion (612) of the wind shield (61), and the outer end surface of each first blade (623) located on the outer surface of the impeller (62) and the inner surface of the first truncated cone-shaped cavity (6121) of the front end portion (612) of the wind shield (61) form an air duct gap.

2. The brushless motor according to claim 1, Features: The height of each first blade (623) gradually decreases from the air inlet end to the air outlet end.

3. The brushless motor according to claim 1, Features: The thickness of each first blade (623) gradually increases from the air inlet end to the air outlet end.

4. The brushless motor according to claim 1, Features: Each first blade (623) is evenly arranged on the outer surface of the wheel disc (621) in an inclined manner along the rotation direction of the brushless motor.

5. The brushless motor according to claim 1, Features: Both side surfaces of the contact point between each first blade (623) and the outer surface of the wheel disc (621) are arc-shaped contact surfaces.

6. The brushless motor according to claim 1, Features: The outer surface of the rear end of the housing (10) is provided with at least two windows (19) which are connected to the inner surface.

7. The brushless motor according to claim 1, Features: The rear cover (40) is also open at both ends and hollow inside. The rear bearing chamber (45) is located on the rear bearing chamber fixing block (41). The rear bearing chamber fixing block (41) is fixed to the inner wall of the rear cover (40) by at least two third ribs (42). A fourth air duct (43) for air flow is formed between two adjacent third ribs (42).

8. The brushless motor according to any one of claims 1 to 7, Features: The air duct system component (60) further comprises a fixed impeller (63), the fixed impeller (63) comprising an outer cylindrical portion (631) with openings at both ends and a hollow interior, an inner cylindrical portion (632) with openings at both ends and a hollow interior, and a central cylindrical portion (633); the inner cylindrical portion (632) is fixed to the inner wall of the outer cylindrical portion (631) via a plurality of second blades (634), and a fifth air duct (635) for air flow is formed between two adjacent second blades (634); the central cylindrical portion (633) is connected to the inner wall of the outer cylindrical portion (631) via at least two fourth blades (634); The ribs (636) are fixed on the inner wall of the inner cylindrical portion (632); the outer cylindrical portion (631) of the fixed impeller (63) is fixed on the front end portion (612) of the wind hood (61); the first air duct (6113) and the first conical cavity (6121) of the wind hood (61) together with the first blades (623) and the second air duct (624) of the impeller (62), and the fifth air duct (635) of the fixed impeller (63) constitute an air duct for air flow to flow in the air duct system component (60).

9. An impeller (62), Features: The impeller (62) is open at one end and is trumpet-shaped, comprising a trumpet-shaped wheel disc (621), a wheel disc bottom (622) connected to the wheel disc (621), and a plurality of first blades (623). The radial dimension gradually increases from the wheel disc bottom (622) to the open end of the wheel disc (621) to form a trumpet shape, so that the inner surface of the wheel disc (621) is a trumpet-shaped second truncated cone cavity (6211). The plurality of first blades (623) are evenly arranged on the outer surface of the wheel disc (621) to form an integral structure with the outer surface of the wheel disc (621). Two adjacent first blades (623) are connected to each other. A second air duct (624) for air flow is formed between the blades (623); a central through hole (6221) is provided at the bottom (622) of the wheel disc; the height of each first blade (623) gradually decreases from the air inlet end to the air outlet end; the thickness of each first blade (623) gradually increases from the air inlet end to the air outlet end; each first blade (623) is evenly arranged on the outer surface of the wheel disc (621) in an inclined manner along the rotation direction of the brushless motor; and both side surfaces of each first blade (623) at the contact point with the outer surface of the wheel disc (621) are arc-shaped contact surfaces.

Images