Fan and ground cleaning equipment

Abstract

The utility model discloses a fan and ground cleaning equipment with the fan. The fan comprises a shell, a motor and a diffuser. A first containing space and an air inlet communicated with the first containing space are formed in the shell, at least part of the motor is arranged in the first containing space, the motor is provided with an output shaft, the diffuser is arranged on the motor in a sleeving mode and connected with the motor, the diffuser comprises a first diffuser body, the first diffuser body is located in the first containing space, and the first diffuser body is provided with a plurality of first blades. Each first blade comprises a windward side and a leeward side which are arranged oppositely, and each first blade is provided with a vent hole communicated with the windward side and the leeward side. According to the fan and the ground cleaning equipment with the fan, the first blade is provided with the vent hole, so that the windward side is communicated with the leeward side, and gas can directly flow to one side of the leeward side of the first blade through the vent hole, so that the pressure difference between the windward side and the leeward side is reduced, and the aerodynamic force on the surface of the first blade is reduced; finally, the aerodynamic noise is reduced.

Description

Technical Field

[0001] The present application relates to the technical field of cleaning equipment, and more specifically, to a fan and floor cleaning equipment. Background Art

[0002] A fan is a machine that relies on mechanical energy to increase gas pressure and discharge the gas. Fans are mainly used in floor cleaning equipment such as vacuum cleaners. Fans usually include impellers and diffusers. The impeller rotates to generate airflow, which is then discharged after being expanded by the diffuser. However, the gas is sucked into a narrow space due to the rotation of the impeller, and the high-speed airflow will collide and rub against the diffuser, causing vibration and noise. Utility Model Content

[0003] Embodiments of the present application provide a fan and a floor cleaning device having the fan.

[0004] A fan according to an embodiment of the present application includes:

[0005] a housing, wherein the housing is formed with a first accommodating space and an air inlet communicating with the first accommodating space;

[0006] a motor, wherein the motor is at least partially disposed in the first accommodating space;

[0007] A diffuser, wherein the diffuser is sleeved on the motor and connected to the motor, the diffuser comprises a first diffuser, the first diffuser is located in the first accommodating space, the first diffuser has a plurality of first blades, the first blades comprise a windward surface and a leeward surface arranged opposite to each other, and each of the first blades is provided with an air vent connecting the windward surface and the leeward surface.

[0008] In some embodiments, projections of two adjacent first blades along a direction perpendicular to the windward surface at least partially overlap, and positions of the vents overlap with projections of inlet ends of adjacent first blades along the first direction.

[0009] In some embodiments, the diffuser further comprises:

[0010] a second diffuser, the second diffuser comprising an annular side wall and a plurality of second blades, the plurality of second blades being arranged circumferentially along an inner wall of the annular side wall, and the annular side wall being further connected to the casing; or

[0011] The diffuser further comprises:

[0012] A third diffuser is located between the second diffuser and the first diffuser, and has a plurality of third blades.

[0013] In some embodiments, an end surface of the first blade outlet end is coplanar with an end surface of the third blade inlet end, and an end surface of the third blade outlet end is coplanar with an end surface of the second blade inlet end.

[0014] In some embodiments, the annular side wall is connected to the housing by interference fit.

[0015] In certain embodiments, the annular sidewall forms a cavity, and the third diffuser is located within the cavity.

[0016] In some embodiments, the second diffuser is provided with a support frame, the support frame is connected to the motor, and the third diffuser is provided with a fixing groove, the fixing groove matches the support frame.

[0017] In some embodiments, the first diffuser further includes a first connecting portion, the first connecting portion is connected to the support frame, and the plurality of first blades are circumferentially arranged along an outer edge of the first connecting portion.

[0018] In some embodiments, the first diffuser further includes a plurality of fourth blades, each of the fourth blades is connected to an air outlet end of one of the first blades, a drainage gap is formed between two adjacent fourth blades, the fourth blades are connected to the first blades in a one-to-one correspondence, the plurality of fourth blades enclose a second accommodating space, and the drainage gap is connected to the second accommodating space.

[0019] In some embodiments, an inner surface of the fourth blade is in communication with the leeward surface of the first blade, and an outer surface of the fourth blade is in communication with the windward surface of the first blade.

[0020] A floor cleaning device according to another embodiment of the present application comprises the fan as claimed in any one of the above claims.

[0021] A fan and a floor cleaning device having the fan proposed in the embodiments of the present application have a first blade with an air vent so that the windward side and the leeward side are connected. When the impeller draws air into the casing to form a high-speed airflow, the high-speed airflow impacts the windward side of the first blade. At this time, part of the gas will flow directly to the leeward side of the first blade through the air vent to reduce the pressure difference between the windward side and the leeward side, thereby reducing the aerodynamic force on the surface of the first blade, and ultimately reducing the aerodynamic noise.

[0022] Additional aspects and advantages of the embodiments of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the embodiments of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0024] Figure 1 is a schematic structural diagram of a fan according to an embodiment of the present application;

[0025] Figure 2 is a schematic structural diagram of a motor according to an embodiment of the present application;

[0026] Figure 3 is a schematic structural diagram of a first diffuser in an embodiment of the present application;

[0027] Figure 4 is a schematic diagram of the position of the vent openings in an embodiment of the present application;

[0028] Figure 5 is a noise spectrum diagram generated when the vent holes of the embodiment of the present application are in different positions;

[0029] Figure 6 is a schematic structural diagram of the first diffuser from another perspective in an embodiment of the present application;

[0030] Figure 7 is a schematic structural diagram of a second diffuser in an embodiment of the present application;

[0031] Figure 8 is a schematic structural diagram of a third diffuser according to an embodiment of the present application;

[0032] Fig. 9 It is a schematic structural diagram of the impeller of an embodiment of the present application.

[0033] Description of the main component symbols: fan 100, housing 10, air inlet 11, first accommodating space 12, motor 20, output shaft 21, limiting groove 22, coil winding 23, diffuser 30, first diffuser 31, first blade 311, vent hole 312, first connecting portion 313, avoidance hole 3131, stepped slot hole 3132, fourth blade 314, drainage gap 315, second accommodating space 316, second diffuser 32, Annular side wall 321, connecting groove 3211, second blade 322, first inner connecting ring 323, limiting boss 3231, cavity 324, support frame 325, fixing ring 3251, supporting foot 3252, third diffuser 33, third blade 331, second inner connecting ring 332, fixing groove 3321, impeller 40, top cover 41, fifth blade 42, base 43, second connecting portion 431, air inlet 44, air outlet 45. DETAILED DESCRIPTION

[0034] The following further describes the embodiments of the present application in conjunction with the accompanying drawings. The same or similar reference numerals in the accompanying drawings represent the same or similar elements or elements with the same or similar functions.

[0035] In addition, the embodiments of the present application described below in conjunction with the drawings are exemplary and are only used to explain the embodiments of the present application and should not be construed as limiting the present application.

[0036] In the present application, unless otherwise clearly specified and limited, a first feature being “above” or “below” a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being “above”, “above”, and “above” a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being “below”, “below”, and “below” a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0037] The fan 100 in the existing vacuum cleaner is composed of a housing 10, an impeller 40, and a diffuser 30. The diffuser 30 includes a bladeless diffuser, a primary diffuser, and a secondary diffuser. The blade frequency aerodynamic noise of the fan 100 is caused by the static and dynamic interference between the trailing edge airflow of the impeller 40 and the leading edge of the diffuser 30 blade. The traditional design is to completely seal the diffuser flow channel, which is very effective in improving efficiency, but there are still defects. For example, the trailing edge airflow of the impeller 40 impacts the leading edge of the blade of the diffuser with blades, resulting in harsh blade frequency noise, which seriously affects the user experience. In addition, since the speed of the impeller 40 is very high, the airflow velocity at the outlet of the diffuser 30 is too fast, and the noise is proportional to the sixth power of the airflow velocity, so the aerodynamic noise is very obvious. However, if a bladeless diffuser is used, the turbulent noise will increase, and the noise will still not be effectively solved.

[0038] In view of this, please refer to Figure 1 The present application discloses a floor cleaning device, which includes a fan 100 including a housing 10, a motor 20 and a diffuser 30.

[0039] The shell 10 is formed with a first accommodating space 12 and an air inlet 11 connected to the first accommodating space 12. The motor 20 is at least partially arranged in the first accommodating space 12. The diffuser 30 is sleeved on the motor 20 and connected to the motor 20. The diffuser 30 includes a first diffuser 31. The first diffuser 31 is located in the first accommodating space 12. The first diffuser 31 has a plurality of first blades 311. The first blades 311 include a windward surface and a leeward surface arranged back to back. Each first blade 311 is provided with an air vent 312 connecting the windward surface and the leeward surface.

[0040] A fan 100 and a floor cleaning device having the fan 100 proposed in the embodiment of the present application connect the windward side and the leeward side by opening an air vent 312 on the first blade 311. When the impeller 40 draws air into the casing 10 to form a high-speed airflow, the high-speed airflow impacts the windward side of the first blade 311. At this time, part of the gas will flow directly to the leeward side of the first blade 311 through the air vent 312 to reduce the pressure difference between the windward side and the leeward side, thereby reducing the aerodynamic force on the surface of the first blade 311, and finally reducing the aerodynamic noise.

[0041] See also Figure 2 The motor 20 is an important component of the fan 100 and is generally divided into a brushed motor and a brushless motor. The brushed motor has low cost and mature technology, but short life, high noise, and severe heat generation; the brushless motor has low noise and long life, but high price. Since the performance of the brushless motor is better than that of the brushed motor and the noise is lower, in this embodiment, the motor 20 is a brushless motor, wherein the motor 20 has an output shaft 21.

[0042] See also Figure 4 The fan 100 also includes an impeller 40, which is arranged on the output shaft 21. The impeller 40 is located between the air inlet 11 and the first diffuser 31. Specifically, the impeller 40, as an energy conversion component, is an important component of the fan 100, and is used to inhale air and accelerate the discharge, thereby generating power or pressure. The impeller 40 includes a top cover 41, a fifth blade 42 and a base 43. An air inlet 44 is opened in the middle of the top cover 41, and a second connecting portion 431 is provided in the middle of the base 43. The second connecting portion 431 is connected to the output shaft 21 of the motor 20. The fifth blade 42 surrounds the second connecting portion 431 and is arranged on the base 43. One side of the fifth blade 42 is connected to the base 43, and the other side is connected to the top cover 41. The top cover 41, the base 43 and the two adjacent fifth blades 42 enclose an exhaust channel, and an exhaust port 45 is formed at the edge of the base 43. When the impeller 40 rotates, air is inhaled from the air inlet 44 and discharged from the exhaust port 45 after passing through the exhaust channel.

[0043] See also Figure 1 The diffuser 30 is a device for expanding the suction power of the vacuum cleaner. Its working principle is mainly to increase the suction power of the vacuum cleaner by slowing down the high-speed flowing air and expanding its cross-sectional area. That is, the diffuser 30 introduces the sucked air and dust from a small opening into a gradually expanding space. In this process, the velocity of the fluid gradually decreases, while the pressure gradually increases. In this way, the diffuser 30 can convert the low-pressure, high-speed airflow sucked by the vacuum cleaner into a high-pressure, low-speed airflow. This conversion increases the suction power of the vacuum cleaner, enabling it to clean various surfaces more effectively.

[0044] The first blade 311 is tilted relative to the output shaft 21. When the motor 20 rotates, air enters the inside of the fan 100 housing 10. At this time, the air is directly blown to the windward side of the first blade 311, and the other side is the leeward side of the first blade 311. The vent 312 runs through the first blade 311 to connect the windward side and the leeward side. Preferably, the opening direction of the vent 312 should be parallel to the first direction so that the air can directly pass through the vent 312 without being blocked and affecting the effect of the vent 312.

[0045] See also Figures 3 to 5 In some embodiments, the projections of two adjacent first blades 311 in a direction perpendicular to the windward surface at least partially overlap, and the position of the vent 312 overlaps with the projection of the inlet end of the adjacent first blade 311 in a direction perpendicular to the windward surface. The inlet end of the first blade 311 refers to the inlet edge of the first blade 311, that is, the starting position of the air flowing into the first blade 311, and correspondingly, the outlet end of the first blade 311 refers to the outlet edge of the first blade 311, that is, the position where the air flows out of the first blade 311. In other embodiments, in order to improve the performance of the diffuser, the curvature of the outlet end can also be adjusted to guide the air to flow out of the diffuser blade better, or some protrusions or recessed structures can be added to the outlet end to reduce the disturbance and loss of the air flow.

[0046] Specifically, Figure 4 As shown in the figure, the five positions numbered x1, x2, x3, x4, and x5 from right to left are respectively the punching positions of five different vent holes 312, such as Figure 5 As shown, it is a frequency spectrum diagram of the air holes 312 opened at different positions of the blades, wherein the mass-produced prototype is a fan with a first blade 311 without holes, the horizontal axis represents frequency, the unit is hertz, and the vertical axis represents noise sound power, that is, the total energy of sound radiated into the space by the noise source per unit time, the unit is watt or dB (A), wherein the smaller the noise sound power, the better the noise reduction effect. According to the data given in the figure, it can be concluded that when the position of the air hole 312 coincides with the projection of the inlet end of the adjacent first blade 311 along the first direction, that is, when the air hole 312 is located at x3, the noise sound power is 99.3 at this time, and when the position of the air hole 312 is just outside the projection of the inlet end of the adjacent first blade 311 along the first direction, that is, when the air hole 312 is located at x4, the noise sound power is 99.3 at this time, and the noise reduction effect is best.

[0047] See also Figure 1In some embodiments, the diffuser 30 further includes a second diffuser 32 and a third diffuser 33. The second diffuser 32 includes an annular sidewall 321 and a plurality of second blades 322. The plurality of second blades 322 are circumferentially arranged along the inner wall of the annular sidewall 321. The annular sidewall 321 is also connected to the housing 10. The third diffuser 33 is located between the second diffuser 32 and the first diffuser 31. The third diffuser 33 has a plurality of third blades 331. Specifically, as Figure 7 As shown, the second diffuser 32 further includes a first inner connecting ring 323, which is sleeved on the outside of the motor 20. One end of the second blade 322 is connected to the annular side wall 321, and the other end is connected to the first inner connecting ring 323. Figure 8 As shown, the third diffuser 33 further includes a second inner connecting ring 332, which is sleeved on the outside of the motor 20, and a plurality of third blades 331 are arranged circumferentially along the outer wall of the second inner connecting ring 332. The second blades 322 and the third blades 331 are both arc-shaped in cross section, and the second blades 322 and the third blades 331 are both inclined relative to the output shaft 21. The fan 100 in this embodiment adopts a three-stage diffusion method, which further reduces the airflow velocity when the air flows out of the diffuser 30, thereby suppressing broadband noise.

[0048] The inlet angle refers to the angle between the blade surface and the inlet airflow, and the outlet angle refers to the angle between the blade surface and the outlet airflow. The size of both depends on the design and operating conditions of the blade. By adjusting the inlet and outlet angles of the blade, the air flow process can be optimized, turbulence and eddy currents can be reduced, and the suction and performance of the vacuum cleaner can be improved. At the same time, it can also reduce noise generation and improve the comfort and service life of the vacuum cleaner. Generally, the larger the inlet angle, the larger the outlet angle. This is because during operation, the angular momentum of the inlet flow must match the angle of the blade to achieve the best diffusion effect.

[0049] In some embodiments, the end face of the outlet end of the first blade 311 is coplanar with the end face of the inlet end of the third blade 331, and the end face of the outlet end of the third blade 331 is coplanar with the end face of the inlet end of the second blade 322. Specifically, the end faces of the inlet and outlet ends of the first blade 311, the second blade 322, and the third blade 331 are all planes. Such a configuration can reduce the occurrence of these turbulence and eddy currents, improve the performance of the vacuum cleaner, reduce the loss of air flow, thereby improving the suction power of the vacuum cleaner, reduce the disturbance of air flow, and reduce the generation of noise. It can reduce the friction and impact of air flow, reduce the loss to the blades and the entire vacuum cleaner, and thus extend the service life of the vacuum cleaner.

[0050] In some embodiments, the annular side wall 321 is connected to the housing 10 by interference fit. Specifically, the housing 10 is sleeved on the annular side wall 321, a connection groove 3211 is provided at the edge of the annular side wall 321, the inner side wall of the housing 10 abuts against the bottom wall of the connection groove 3211, the end face of the housing 10 abuts against the side wall of the connection groove 3211, the outer surface of the housing 10 is coplanar with the outer wall surface of the annular side wall 321, and the diameter of the circle where the inner side wall of the housing 10 is located is slightly smaller than the diameter of the circle where the bottom wall of the connection groove 3211 is located, so that the annular side wall 321 and the housing 10 are connected by interference fit. In this way, a seal can be formed between the annular side wall 321 and the housing 10, thereby guiding the air to flow to the second diffuser 32 and the third diffuser 33, and preventing the air from leaking out and generating noise.

[0051] In some embodiments, the annular sidewall 321 forms a cavity 324, and the third diffuser 33 is located in the cavity 324. Specifically, the cavity 324 is used to extend and expand the first cavity 324, that is, to expand the cavity volume of the diffuser. In other embodiments, the third diffuser 33 may also be disposed in the first cavity 324, which may be selected according to actual production or assembly requirements.

[0052] See also Figure 7 and Figure 8 In some embodiments, the second diffuser 32 is provided with a support frame 325, and the support frame 325 is connected to the motor 20. The third diffuser 33 is provided with a fixing groove 3321, and the fixing groove 3321 matches the support frame 325. Specifically, the support frame 325 includes a fixing ring 3251 and support feet 3252 uniformly connected to the circumference of the fixing ring 3251. The fixing ring 3251 is sleeved on the outside of the output shaft 21 and does not contact the output shaft 21. The support feet 3252 are connected to the first inner connecting ring 323. The connection between the first inner connecting ring 323 and the fixing frame is also provided with a limiting boss 3231 downward along the direction of the supporting foot 3252. Such a configuration can strengthen the connection strength between the supporting foot 3252 and the first inner connecting ring 323. The side of the motor 20 is provided with a limiting groove 22 that matches the limiting boss 3231. Figure 2 As shown, the second diffuser 32 is limited in cooperation with the limiting boss 3231 to prevent the second diffuser 32 from rotating under the influence of air. A fixing groove 3321 is provided on the second inner connecting ring 332 of the third diffuser 33. The fixing groove 3321 is arranged corresponding to the position of the supporting foot 3252 of the supporting frame 325. When the third diffuser 33 is arranged in the cavity 324, the fixing groove 3321 is stuck on the supporting foot 3252 to prevent the third diffuser 33 from rotating under the influence of air and generating noise.

[0053] See also Figure 3In some embodiments, the first diffuser 31 further includes a first connection portion 313, the first connection portion 313 is connected to the support frame 325, and a plurality of first blades 311 are arranged circumferentially along the outer edge of the first connection portion 313. Specifically, a avoidance hole 3131 is provided in the middle of the first connection portion 313, the avoidance hole 3131 is used to avoid the fixing ring 3251 of the second diffuser 32, three stepped slots 3132 are evenly arranged around the avoidance hole 3131, the first connection portion 313 is detachably connected to the support frame 325 through a fastener penetrating the stepped slots 3132, and the end surface of the first diffuser 31 close to the air inlet 11 is coplanar with the inlet end of the first blade 311. Such an arrangement can prevent the first diffuser 31 from rotating under the drive of air, causing the first diffuser 31 to fail.

[0054] See also Figure 2 and Figure 6 In some embodiments, the first diffuser 31 further includes a plurality of fourth blades 314, each of which is connected to an outlet end of a first blade 311, and a drainage gap 315 is formed between two adjacent fourth blades 314. The fourth blades 314 are connected to the first blades 311 in a one-to-one correspondence, and the plurality of fourth blades 314 enclose a second accommodating space 316, and the drainage gap 315 is connected to the second accommodating space 316. The fourth blades 314 are arranged from the edge of the first connecting portion 313 and are bent toward the inside of the first connecting portion 313, along the diameter of the first connecting portion 313. In vertical projection, two adjacent fourth blades 314 at least partially overlap, and the second accommodating space 316 is used to set the motor 20. Specifically, the second accommodating space 316 contains part of the coil winding 23 of the motor 20. When air enters the motor 20 along the nearest air inlet 11, it is affected by the first blade 311 and flows along the windward surface of the first blade 311. Part of the air will flow into the second accommodating space 316 along the drainage gap 315 and blow directly to the coil winding 23 of the motor 20, thereby cooling the previous winding, thereby avoiding overheating, malfunctioning or even scrapping of the motor 20, and improving the service life of the fan 100.

[0055] Furthermore, the inner surface of the fourth blade 314 is connected to the leeward side of the first blade 311, and the outer surface of the fourth blade 314 is connected to the windward side of the first blade 311. This arrangement allows air to flow into the second accommodating space 316 along the drainage slit 315 without any obstruction, avoiding unnecessary collision and friction between the high-speed air and the blades, thereby increasing the service life of the blades, and avoiding unnecessary vibration to reduce noise generation.

[0056] In the description of this specification, the description with reference to the terms "certain embodiments", "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiments or examples are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0057] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of this application, the meaning of "plurality" is at least two, such as two, three, unless otherwise clearly and specifically defined.

[0058] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations on the present application. Ordinary technicians in this field can change, modify, replace and modify the above embodiments within the scope of the present application. The scope of the present application is defined by the claims and their equivalents.

Claims

1. A fan, characterized in that: include: a housing, wherein the housing is formed with a first accommodating space and an air inlet communicating with the first accommodating space; a motor, wherein the motor is at least partially disposed in the first accommodating space; A diffuser, wherein the diffuser is sleeved on the motor and connected to the motor, the diffuser comprises a first diffuser, the first diffuser is located in the first accommodating space, the first diffuser has a plurality of first blades, the first blades comprise a windward surface and a leeward surface arranged opposite to each other, and each of the first blades is provided with an air vent connecting the windward surface and the leeward surface.

2. The fan according to claim 1, characterized in that: The projections of two adjacent first blades along a direction perpendicular to the windward surface at least partially overlap, and the positions of the vent holes overlap with the projections of the inlet ends of the adjacent first blades along a direction perpendicular to the windward surface.

3. The fan according to claim 1, characterized in that: The diffuser further comprises: a second diffuser, the second diffuser comprising an annular side wall and a plurality of second blades, the plurality of second blades being arranged circumferentially along an inner wall of the annular side wall, and the annular side wall being further connected to the casing; or The diffuser further comprises: A third diffuser is located between the second diffuser and the first diffuser, and has a plurality of third blades.

4. The fan according to claim 3, characterized in that: The end surface of the first blade outlet end is coplanar with the end surface of the third blade inlet end, and the end surface of the third blade outlet end is coplanar with the end surface of the second blade inlet end.

5. The fan according to claim 3, characterized in that: The annular side wall is connected to the housing by interference fit.

6. The fan according to claim 3, characterized in that: The annular side wall forms a cavity, and the third diffuser is located in the cavity.

7. The fan according to claim 3, characterized in that: The second diffuser is provided with a support frame, and the support frame is connected to the motor. The third diffuser is provided with a fixing groove, and the fixing groove matches the support frame.

8. The fan according to claim 7, characterized in that: The first diffuser further includes a first connecting portion, the first connecting portion is connected to the supporting frame, and a plurality of the first blades are circumferentially arranged along an outer edge of the first connecting portion.

9. The fan according to claim 1, characterized in that: The first diffuser also includes a plurality of fourth blades, each of the fourth blades is connected to an air outlet end of the first blade, a drainage gap is formed between two adjacent fourth blades, the fourth blades are connected to the first blades in a one-to-one correspondence, the plurality of fourth blades enclose a second accommodating space, and the drainage gap is connected to the second accommodating space.

10. The fan according to claim 9, characterized in that: An inner surface of the fourth blade is in communication with the leeward surface of the first blade, and an outer surface of the fourth blade is in communication with the windward surface of the first blade.

11. A floor cleaning device, characterized in that: Including the fan described in any one of claims 1-10.

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