CN114658676A

CN114658676A - Fan and cleaning equipment

Info

Publication number: CN114658676A
Application number: CN202210411246.2A
Authority: CN
Inventors: 杨帆; 龚涛; 杨志鹏; 吴昕耿; 曹红军; 张肃
Original assignee: Guangdong Meizhi Compressor Co Ltd
Current assignee: Guangdong Meizhi Compressor Co Ltd
Priority date: 2022-04-19
Filing date: 2022-04-19
Publication date: 2022-06-24
Anticipated expiration: 2042-04-19
Also published as: CN114658676B

Abstract

The invention discloses a fan and cleaning equipment, and relates to the technical field of fan equipment, wherein the fan comprises a casing, a shaft sleeve and a rotor system, the shaft sleeve is fixed on the casing, the rotor system comprises an impeller, a main shaft, a first thrust disk, a second thrust disk and a rotor, the main shaft is rotatably arranged in the shaft sleeve and is in clearance fit with the shaft sleeve to form a radial bearing, the friction force between the main shaft and the shaft sleeve is reduced, the impeller and the rotor are respectively fixed at two ends of the main shaft, the first thrust disk and the second thrust disk are fixed on the main shaft and are respectively in clearance fit with two ends of the shaft sleeve to form two thrust bearings with opposite acting force directions, the thrust forces of the two thrust bearings are respectively designed to be the sum of the gravity of the rotor system and the maximum axial gas force of the impeller which are 1.2-2 times of the maximum rotating speed of the fan, the stable operation of the rotor system can be ensured, and the stable operation under the highest rotating speed can be realized in various orientations, the performance and the mechanical noise of the fan are improved, and the stability and the highest rotating speed of the fan are improved.

Description

Fan and cleaning equipment

Technical Field

The invention relates to the technical field of fan equipment, in particular to a fan and cleaning equipment.

Background

The fan for the dust collector generates negative pressure at the inlet of the fan by rotating and doing work through the impeller, so that suction force is generated on dust and the like. The rotating shaft of the traditional impeller is generally supported by the ball bearing, but the ball bearing can generate mechanical friction during operation, particularly, the mechanical friction of the ball bearing is more obvious after the rotating speed of the impeller is increased, so that the mechanical efficiency is obviously reduced, abnormal vibration and noise can be generated, and the service life of the ball bearing is shortened.

In the related technology, the blower adopts a gas bearing consisting of a radial bearing and a thrust bearing to replace a ball bearing, but because the blower has various use working conditions in the use process, the supporting effect of the gas bearing when the rotor system runs in any direction directly influences the rotating speed of the rotor system, and further influences whether the blower can reach the highest running speed.

Disclosure of Invention

The present invention is directed to solving at least one of the problems of the prior art. Therefore, the invention provides the fan which can stably meet the requirement of the highest running speed in any direction.

The invention also provides cleaning equipment with the fan.

Blower according to an embodiment of the first aspect of the inventionThe method comprises the following steps: a housing provided with a support frame; the shaft sleeve is fixed on the support frame; the rotor system comprises an impeller, a main shaft, a first thrust disc, a second thrust disc and a rotor, wherein the main shaft is rotatably arranged in the shaft sleeve, part of the outer peripheral wall of the main shaft is in clearance fit with the inner peripheral wall of the shaft sleeve, the impeller is fixed at one end of the main shaft, the rotor is fixed at the other end of the main shaft, the first thrust disc is fixed on the main shaft and is in clearance fit with the shaft sleeve, a first end wall is arranged at one end, facing the shaft sleeve, of the first thrust disc, a plurality of first grooves are formed in the first end wall or the opposite end wall of the shaft sleeve, the first grooves are circumferentially arranged at intervals along the main shaft, the second thrust disc is fixed on the main shaft and is in clearance fit with the shaft sleeve, a second end wall is arranged at one end, facing the shaft sleeve, of the second thrust disc, and a plurality of second grooves are formed in the second end wall or the opposite end wall of the shaft sleeve, the second grooves are arranged at intervals along the circumferential direction of the main shaft; the stator is arranged around the periphery of the rotor; the gravity of the rotor system is G, the diameter of a suction port of the impeller is D11, and the maximum outer diameter of the impeller is D12; the maximum vacuum degree of the fan is P, the thrust of the first thrust disk is F1, the thrust of the second thrust disk is F2 under the maximum rotating speed of the fan, and the following requirements are met: 1.2 ≤ F1/(G + P (π D12)²/4-πD11²/4)) is less than or equal to 2, and 1.2 is less than or equal to F2/(G + P (Pi D12)²/4-πD11²/4））≤2。

The fan provided by the embodiment of the invention at least has the following beneficial effects:

the main shaft is rotatably arranged in a radial bearing formed by the shaft sleeve, and the radial bearing provides radial bearing force for the rotor system to ensure that the main shaft is separated from the shaft sleeve when rotating at high speed, so that the friction force between the main shaft and the shaft sleeve is reduced; the first thrust disk and the second thrust disk are fixed on the main shaft and form two thrust bearings with opposite acting force directions with the shaft sleeve respectively, under the maximum rotating speed of the fan, the thrust forces of the two thrust bearings are designed to be the sum of the gravity of the rotor system and the maximum axial gas force of the impeller which are 1.2-2 times, the shaft sleeve can be ensured to be separated from the first thrust disk and the second thrust disk, the stability of the rotor system in the axial direction is improved, the influence of the fan on the running of the rotor system when the fan works in any direction is reduced, the deflection of the rotor system is effectively reduced, the rotor system can stably run at the highest rotating speed under various working conditions, and the requirements of miniaturization and light weight of the fan are ensured; the friction of the rotor system is reduced by adopting the gas bearing, so that the operation of the rotor system is more stable, the performance and the mechanical noise of the fan are improved, and the stability and the highest rotating speed of the fan are improved.

According to some embodiments of the invention, 1.4 ≦ F1/(G + P (π D12)²/4-πD11²/4))/< 1.6, and 1.4 < F2/(G + P (π D12)²/4-πD11²/4））≤1.6。

According to some embodiments of the invention, a plurality of first grooves are provided in the first end wall, the first grooves extending toward the axis of the main shaft and extending in a direction inclined in a direction opposite to a direction of rotation around the first thrust disk.

According to some embodiments of the invention, an end of the first groove remote from the axis is located at a peripheral edge of the first end wall.

According to some embodiments of the invention, a plurality of the first grooves are identical in structure and form a first reference circle towards one end of the axis, the diameter of the first reference circle is D21, the number of the first grooves is n, and the width of the first grooves on the first reference circle is B, so that: nB/Pi D21 is more than or equal to 20% and less than or equal to 65%.

According to some embodiments of the present invention, the first groove includes a first outer profile and a first inner profile sequentially arranged along a rotation direction of the first thrust disk, a tangential angle of the first outer profile at an outer circumferential edge of the first end wall is λ 1, and the following is satisfied: λ 1 is more than or equal to 45 degrees and less than or equal to 80 degrees.

According to some embodiments of the invention, the first groove is a skewed slot or a spiral groove.

According to some embodiments of the invention, the first end wall or the opposite end wall of the shaft sleeve is provided with a plurality of first connecting grooves, and the plurality of first connecting grooves are correspondingly connected to one ends of the plurality of first grooves facing the axis respectively and are arranged in a bending way relative to the first grooves.

According to some embodiments of the invention, the first groove is formed by laser machining, etching machining or electric discharge machining.

According to some embodiments of the present invention, the main shaft includes a journal and a shaft body, the journal has a diameter larger than that of the shaft body, the first thrust disk is sleeved on the shaft body and abuts against one end of the journal facing the impeller, and the second thrust disk is sleeved on the shaft body and abuts against one end of the journal away from the impeller.

According to some embodiments of the invention, the length of the bushing is less than the length of the journal by a difference of 8 μm to 16 μm.

According to some embodiments of the invention, the outer diameter of the journal is D31, one end of the first grooves facing the axis of the main shaft forms a first reference circle, the diameter of the first reference circle is D21, and the outer diameter of the shaft sleeve is D41, which satisfies: d21 is more than or equal to D31, and D21 is more than or equal to D41.

According to some embodiments of the invention, the journal has an outer diameter D31, and the shaft body has an outer diameter D32, such that: D32/D31 is more than or equal to 40% and less than or equal to 80%, and D32 is more than or equal to 4 mm.

According to some embodiments of the invention, the second thrust disk is annular, the outer diameter of the second thrust disk is D22, the inner diameter of the stator is D51, and the outer diameter of the journal is D31, so that: 1.3D31 is not less than D22 is not less than 0.98D 51.

According to some embodiments of the invention, the journal has a length L0, and the spindle has a length L, such that: l0 is more than or equal to 0.2L and less than or equal to 0.8L.

According to some embodiments of the invention, the outer circumferential wall of the journal is in clearance fit with the inner circumferential wall of the sleeve, and one of the outer circumferential wall of the journal and the inner circumferential wall of the sleeve is provided with a plurality of third grooves, and the plurality of third grooves are arranged at intervals in the circumferential direction of the main shaft.

According to some embodiments of the invention, the inner diameter of the bushing is larger than the outer diameter of the journal by a difference of 4 μm to 10 μm.

According to some embodiments of the invention, a plurality of third grooves are formed in the outer peripheral wall of the journal and extend spirally in the axial direction of the spindle, and the outer peripheral wall of the journal is further provided with a third connecting groove which is connected to an end of the third groove, which is far away from the end wall of the journal, and bends the device relative to the third groove.

According to some embodiments of the invention, one end of the third groove is located in one of the end walls of the journal.

According to some embodiments of the present invention, one of the outer circumferential wall of the journal and the inner circumferential wall of the sleeve is provided with a plurality of groove sets, the plurality of groove sets are arranged at intervals in the axial direction of the journal, and each groove set includes a plurality of the third grooves which are uniformly distributed in the circumferential direction of the journal.

According to some embodiments of the present invention, the total length of the groove sets along the axial direction of the main shaft is L1, and the length of the shaft journal is L0, so that: L1/L0 is more than or equal to 50 percent and less than or equal to 98 percent.

According to some embodiments of the invention, the first end wall is circular, conical or spherical.

The cleaning device according to the second aspect of the embodiment of the invention comprises the fan described in the above embodiment.

The cleaning device provided by the embodiment of the invention has at least the following beneficial effects:

by adopting the fan of the embodiment of the first aspect, the fan is fixed on a support frame of a shell by arranging a shaft sleeve, and a rotor system comprises an impeller, a main shaft, a first thrust disk, a second thrust disk and a rotor, wherein the main shaft is rotatably arranged in a radial bearing formed by the shaft sleeve, and the radial bearing provides radial bearing force for the rotor system to enable the main shaft to be separated from the shaft sleeve when rotating at high speed, so that the friction force between the main shaft and the shaft sleeve is reduced; the first thrust disk and the second thrust disk are fixed on the main shaft and form two thrust bearings with opposite acting force directions with the shaft sleeve respectively, under the maximum rotating speed of the fan, the thrust forces of the two thrust bearings are designed to be the sum of the gravity of the rotor system and the maximum axial gas force of the impeller which are 1.2-2 times, the shaft sleeve can be ensured to be separated from the first thrust disk and the second thrust disk, the stability of the rotor system in the axial direction is improved, the influence of the fan on the running of the rotor system when the fan works in any direction is reduced, the deflection of the rotor system is effectively reduced, the rotor system can stably run at the highest rotating speed under various working conditions, and the requirements of miniaturization and light weight of the fan are ensured; the friction of the rotor system is reduced by adopting the gas bearing, so that the operation of the rotor system is more stable, the performance and the mechanical noise of the fan are improved, and the stability and the highest rotating speed of the fan are improved.

Additional aspects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.

Drawings

The invention is further described with reference to the following figures and examples, in which:

FIG. 1 is a schematic cross-sectional view of a wind turbine according to an embodiment of the present invention;

FIG. 2 is an exploded view of a blower in accordance with an embodiment of the present invention;

FIG. 3 is a schematic cross-sectional view of a rotor system according to an embodiment of the present invention;

FIG. 4 is an exploded view of a rotor system according to an embodiment of the present invention;

FIG. 5 is a schematic bottom view of an embodiment of the first thrust plate of FIG. 4;

FIG. 6 is a schematic bottom view of another embodiment of the first thrust plate of FIG. 4;

FIG. 7 is a schematic bottom view of another embodiment of the first thrust plate of FIG. 4;

FIG. 8 is a schematic bottom view of an alternate embodiment of the first thrust plate of FIG. 4;

FIG. 9 is a front view of the spindle of FIG. 4;

FIG. 10 is a cross-sectional view of the bushing of FIG. 2;

FIG. 11 is a schematic cross-sectional view of a blower in accordance with another embodiment of the invention;

FIG. 12 is a schematic cross-sectional view of a blower in accordance with another embodiment of the invention.

Reference numerals:

a fan 1000;

a fan housing 100; an air intake passage 110;

an impeller 200;

a first diffuser 300; a first diffuser passage 310;

a housing 400; a support frame 410; a mounting hole 411; a second diffuser 420; a second diffuser channel 421; a rib plate 430;

a main shaft 500; a journal 510; a third groove 511; a third connecting groove 512; a groove group 513; a shaft body 520; a first thrust disk 530; a first end wall 531; a first groove 532; a first connecting groove 533; a second thrust disk 540; a second end wall 541; a second groove 542;

a shaft sleeve 600;

a stator 700;

a rotor 800;

an electronic control board 900.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the accompanying drawings are illustrative only for the purpose of explaining the present invention, and are not to be construed as limiting the present invention.

In the description of the present invention, it should be understood that the orientation descriptions, such as the orientation or positional relationship indicated by upper, lower, etc., are based on the orientation or positional relationship shown in the drawings, and are only for convenience of description and simplification of the description, but do not indicate or imply that the device or element referred to must have a particular orientation, be constructed in a particular orientation, and be operated, and thus should not be construed as limiting the present invention.

In the description of the present invention, a plurality means two or more. If the first and second are described for the purpose of distinguishing technical features, they are not to be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated or implicitly indicating the precedence of the technical features indicated.

In the description of the present invention, unless otherwise explicitly limited, terms such as arrangement, installation, connection and the like should be understood in a broad sense, and those skilled in the art can reasonably determine the specific meanings of the above terms in the present invention in combination with the specific contents of the technical solutions.

Referring to fig. 1 and 2, a blower 1000 according to an embodiment of the present invention may be applied to a vacuum cleaner or other products requiring an ultra-high speed blower. The rotating speed of the super-high speed fan of the dust collector generally exceeds 10 ten thousand revolutions, and reaches 11 ten thousand revolutions or even 13 ten thousand revolutions. Traditional fan adopts ball bearing to support, but ball bearing can produce mechanical friction when the hypervelocity operation for ball bearing's wearing and tearing reduce mechanical efficiency, still can produce abnormal vibration and noise, thereby make ball bearing's life-span show the shortening. Therefore, the gas bearing is adopted to replace the ball bearing, so that the stability of the fan in the process of ultra-high-speed operation is improved.

Referring to fig. 1 and 2, a fan 1000 according to an embodiment of the present invention includes a fan housing 100, an impeller 200, a first diffuser 300, a casing 400, a main shaft 500, and a shaft sleeve 600. The chassis 400 includes a supporting frame 410, the supporting frame 410 is located at the center of the chassis 400, the supporting frame 410 is provided with a mounting hole 411, the shaft sleeve 600 is fixedly mounted in the mounting hole 411, and the main shaft 500 is rotatably disposed in the shaft sleeve 600. It is understood that the shaft sleeve 600 may be fixed to the supporting frame 410 by gluing, or may be fixed by interference fit, clamping, welding, integral molding, and the like, and is not limited in detail herein.

Referring to fig. 1 and 2, it can be understood that the impeller 200 is fixedly coupled to an upper end of the main shaft 500, and the impeller 200 is drivingly coupled to the main shaft 500. The fan housing 100 covers the outer periphery of the impeller 200, both the fan housing 100 and the first diffuser 300 are fixedly connected to the casing 400, and the first diffuser 300 is disposed between the impeller 200 and the support frame 410. An air inlet passage 110 is formed between the impeller 200 and the wind cowl 100, a first diffuser passage 310 is formed between the first diffuser 300 and the wind cowl 100, and the first diffuser passage 310 is communicated with the air inlet passage 110. The impeller 200 rotates to form an air flow, and the kinetic energy of the air flow is increased after the air flow passes through the air inlet passage 110. After the airflow continues to enter the first diffusion channel 310, the first diffusion channel 310 converts kinetic energy of the airflow into air pressure energy, so that the pressure of the airflow is increased, the airflow after diffusion is blown farther, the efficiency of the fan 1000 is increased, and the suction force of the fan 1000 is stronger.

Referring to fig. 2, it can be understood that the casing 400 further includes a second diffuser 420, the second diffuser 420 surrounds the periphery of the support frame 410, and the support frame 410 and the second diffuser 420 are fixedly connected through a rib 430, so that the support frame 410 is more stably connected. The second diffuser 420 forms a second diffuser passage 421, and the second diffuser passage 421 communicates with the first diffuser passage 310. After the airflow of the first diffusion channel 310 is further diffusion processed through the second diffusion channel 421, the diffusion effect can be improved, and noise reduction of the fan 1000 is facilitated.

Referring to fig. 2, a wind turbine 1000 according to an embodiment of the present invention further includes a stator 700, a rotor 800, and an electric control board 900. The rotor 800 is installed at the lower end of the main shaft 500, i.e., the end of the main shaft 500 away from the impeller 200. The stator 700 is fixed to the casing 400, the stator 700 is disposed around the outer circumference of the rotor 800, and the stator 700 and the rotor 800 cooperate to drive the main shaft 500 to rotate, thereby driving the impeller 200 to rotate. The electronic control board 900 is installed on the stator 700 or the casing 400, and the electronic control board 900 is used for controlling the fan 1000.

Referring to fig. 3, it can be understood that the impeller 200, the main shaft 500, the first thrust disk 530, the second thrust disk 540, and the rotor 800 constitute a rotor system. The main shaft 500 includes a journal 510 and a shaft body 520, and an outer diameter dimension of the journal 510 is larger than an outer diameter dimension of the shaft body 520. The main shaft 500 is rotatably arranged in the shaft sleeve 600, the outer peripheral wall of the shaft neck 510 is in clearance fit with the inner peripheral wall of the shaft sleeve 600, the main shaft 500 is rotatably arranged in a radial bearing formed by the shaft sleeve 600 through the shaft neck 510, the main shaft 500 is in clearance fit with the radial bearing along the radial direction of the main shaft 500, the radial clearance is a small clearance, the radial bearing provides radial bearing force for the shaft neck 510, and further provides radial bearing force for a rotor system, so that the main shaft 500 is separated from the shaft sleeve 600 during high-speed rotation, and the friction force between the main shaft 500 and the shaft sleeve 600 is reduced. In addition, the diameter of the journal 510 is increased, so that the contact area between the main shaft 500 and the radial bearing can be effectively increased, and the supporting effect of the radial bearing on the main shaft 500 can be improved.

Referring to fig. 1 and 3, it can be understood that the second thrust disk 540 is annular, the second thrust disk 540 is close to the stator 700, and in order to reduce interference between the second thrust disk 540 and the stator 700, by defining an outer diameter of the second thrust disk 540 as D22, an inner diameter of the stator 700 as D51, an outer diameter of the journal 510 as D31, and satisfying: 1.3D31 is not less than D22 is not less than 0.98D 51. More preferably, it is defined as 1.4D 31. ltoreq.D 22. ltoreq.0.95D 51. In addition, the embodiment of the invention can enable the mass distribution of the whole rotor system to be more uniform through the proportional parameters, and effectively improve the stability of the operation of the fan 1000.

Referring to fig. 4, it can be understood that the outer circumferential wall of the journal 510 is provided with a plurality of third grooves 511, and the plurality of third grooves 511 are uniformly distributed along the circumferential direction of the main shaft 500, but the plurality of third grooves 511 may be provided at intervals in other forms. The plurality of third grooves 511 may be spiral grooves, inclined grooves, etc. It can be understood that an air gap is formed between the outer circumferential wall of the journal 510 and the inner circumferential wall of the shaft sleeve 600, during the high-speed rotation of the main shaft 500, air enters the air gap and forms a local high-pressure region in the third groove 511, and pressure generated by the local high-pressure region generates radial bearing force on the rotor system, so that the journal 510 is completely separated from the shaft sleeve 600, the rotor system is more stable during high-speed operation, and the performance and mechanical noise of the fan 1000 are further improved.

As another embodiment, a plurality of third grooves 511 may be further provided on the inner circumferential wall of the sleeve 600. When the main shaft 500 rotates at a high speed, air may also enter the air gap and form a local high pressure region in the third groove 511, and pressure generated by the local high pressure region generates a radial bearing force on the rotor system, so that the journal 510 is completely separated from the shaft sleeve 600, so that the rotor system is more stable when operating at a high speed, and performance and mechanical noise of the fan 1000 are further improved.

Referring to fig. 4, it can be understood that the first thrust disk 530 and the second thrust disk 540 may be respectively sleeved on the shaft body 520 fixed at two ends of the journal 510, and the first thrust disk 530 and the second thrust disk 540 are fixed by two shoulders (not shown in the figure) formed at the connection of the journal 510 and the shaft body 520. For example, the first thrust disk 530 and the second thrust disk 540 may be fixed to the shaft body 520 by gluing, interference fit, welding, or the like.

It can be understood that the first thrust disk 530 is in clearance fit with the shaft sleeve 600, an axial gap existing between the first thrust disk 530 and the shaft sleeve 600 is a small gap, one end of the first thrust disk 530 facing the shaft sleeve 600 is provided with a first end wall 531, the first end wall 531 is provided with a plurality of first grooves 532, and the plurality of first grooves 532 are arranged at intervals along the circumferential direction of the main shaft 500, so that air enters an air gap during high-speed rotation of the first thrust disk 530 and a local high-pressure region is formed in the first grooves 532, and pressure generated by the local high-pressure region generates an axial first thrust force on the rotor system, which acts as a thrust bearing. As another embodiment, a plurality of first grooves 532 may be further disposed on an end wall of the sleeve 600 opposite to the first end wall 531, so that during the high-speed rotation of the first thrust disk 530, air may enter the air gap and a local high-pressure region may be formed in the first grooves 532, and the pressure generated by the local high-pressure region generates an axial first thrust force for the rotor system.

It can be understood that the second thrust disk 540 is in clearance fit with the shaft sleeve 600, an axial clearance existing between the second thrust disk 540 and the shaft sleeve 600 is a small clearance, one end of the second thrust disk 540 facing the shaft sleeve 600 is provided with a second end wall 541, the second end wall 541 is provided with a plurality of second grooves 542, and the plurality of second grooves 542 are arranged at intervals along the circumferential direction of the main shaft 500, so that during high-speed rotation of the second thrust disk 540, air enters an air gap and a local high-pressure region is formed in the second grooves 542, and pressure generated by the local high-pressure region generates an axial second thrust force on the rotor system, which acts as a thrust bearing. The second thrust force is opposite to the first thrust force. As another embodiment, a plurality of second grooves 542 may be further disposed on an end wall of the sleeve 600 opposite to the second end wall 541, so that when the second thrust disk 540 rotates at a high speed, air may also enter the air gap and a local high pressure region may be formed in the second groove 542, and a pressure generated by the local high pressure region generates an axial second thrust force on the rotor system.

It can be understood that, under the interaction of the first thrust force and the second thrust force, the shaft sleeve 600 can be ensured to be separated from the first thrust disk 530 and the second thrust disk 540, the friction between the shaft sleeve 600 and the first thrust disk 530 and the second thrust disk 540 is reduced, and the rotor system is subjected to stable axial bearing force, so that the operation stability of the rotor system is improved.

Referring to fig. 3, G is defined as the gravity of the rotor system, D11 is the suction port diameter of impeller 200, and D12 is the maximum outer diameter of impeller 200. It is understood that the suction port of the impeller 200 is located at the upper end of the impeller 200, the maximum outer diameter of the impeller 200 is located at the lower end of the impeller 200, and the gravity G of the rotor system, the diameter D11 of the suction port of the impeller 200, and the maximum outer diameter D12 of the impeller 200 can be directly measured. Defining the maximum vacuum degree of the fan 1000 as P, and the first thrust force as F1 and the second thrust force as F2 at the maximum rotation speed of the fan 1000, it should be noted that the fan 1000 is a core component of a cleaning device (such as a dust collector), and the maximum rotation speed of the fan 1000 can also be understood as the corresponding rotation speed of the cleaning device when the cleaning device is operated in the maximum gear. It is understood that the maximum vacuum level P of the blower 1000 is a parameter that can be obtained on the nameplate of the blower 1000. The maximum vacuum degree P of the limit working condition corresponds to the maximum value Fn of the axial gas force of the impeller 200, and the maximum value Fn = P (pi D12) of the axial gas force of the impeller 200 can be calculated by providing the parameters²/4-πD11²4); the first stopping force F1 and the second stopping force F2 may be obtained by pressure sensors.

In order to improve the stability of the rotor system and enable the fan 1000 to stably reach the requirement of the highest speed in any direction, the fan 1000 of the embodiment of the invention designs the first thrust force F1 to be greater than or equal to 1.2 times of the sum of the gravity G of the rotor system and the maximum value Fn of the axial gas force of the impeller 200, and less than or equal to 2 times of the sum of the gravity G of the rotor system and the maximum value Fn of the axial gas force of the impeller 200; the second thrust force F2 is designed to be greater than or equal to 1.2 times the sum of the gravity G of the rotor system and the maximum value Fn of the axial gas force of the impeller 200, and less than or equal to 2 times the sum of the gravity G of the rotor system and the maximum value Fn of the axial gas force of the impeller 200.

The fan 1000 of the embodiment of the present invention is limited by the above parameters, so that the first thrust F1 and the second thrust F2 are not significantly affected by the gravity G of the rotor system and the maximum value Fn of the axial gas force of the impeller 200, and when the fan 1000 works in any direction, the rotor system can be supported under the action of the first thrust F1 and the second thrust F2, so as to ensure that the shaft sleeve 600 can be separated from the first thrust disk 530 and the second thrust disk 540, reduce the influence of the fan 1000 on the operation of the rotor system when working in any direction, effectively reduce the deflection of the rotor system, improve the stability of the rotor system in the axial direction, and enable the rotor system to stably operate at the highest rotation speed under various working conditions. It can be understood that, at the same time, the first thrust force F1 and the second thrust force F2 should not be too large, when the first thrust force F1 and the second thrust force F2 are too large, the outer diameters of the shaft sleeve 600, the first thrust disk 530 and the second thrust disk 540 need to be increased, so that the weight of the rotor system is increased greatly, and the assembly clearance between the shaft sleeve 600 and the first thrust disk 530 and the second thrust disk 540 needs to be reduced excessively, so that the assembly precision requirement is improved, and the assembly difficulty is increased; the requirements for miniaturization and weight reduction of the fan 1000 cannot be satisfied.

The embodiment of the invention reduces the friction of the rotor system by adopting the gas bearing consisting of the radial bearing and the two thrust bearings, so that the operation of the rotor system is more stable, the performance and the mechanical noise of the fan 1000 are improved, and the stability and the highest rotating speed of the fan 1000 are improved.

It is understood that the fan 1000 of the embodiment of the present invention designs the first thrust force F1 to be greater than or equal to 1.4 times the sum of the gravity G of the rotor system and the maximum value Fn of the axial gas force of the impeller 200, and to be less than or equal to 1.6 times the sum of the gravity G of the rotor system and the maximum value Fn of the axial gas force of the impeller 200; the second thrust F2 is designed to be equal to or greater than 1.4 times the sum of the gravity G of the rotor system and the maximum Fn of the gas force in the axial direction of the impeller 200, and equal to or less than 1.6 times the sum of the gravity G of the rotor system and the maximum Fn of the gas force in the axial direction of the impeller 200. The fan 1000 of the embodiment of the invention is limited by the parameters, so that when the fan 1000 works in any direction, the stability of the operation of a rotor system is higher, and the requirements of miniaturization and light weight of the fan 1000 can be met.

Referring to fig. 5, in a first thrust plate 530 according to an embodiment of the present invention, a first end wall 531 is annular. The first grooves 532 are disposed on the first end wall 531, and the first grooves 532 are helical grooves extending in a circumferential direction of the main shaft 500 and extending toward the axis of the main shaft 500. The first groove 532 extends in the same direction as the air inlet direction, i.e., air is introduced from the outer circumference of the first end wall 531 toward the center, and the spiral groove design makes the air flow smoother. The extending direction of the first grooves 532 is inclined along the opposite direction around the rotation direction of the first thrust plate 530, that is, when the rotation direction of the first thrust plate 530 is clockwise, the extending direction of the first grooves 532 is inclined around the counterclockwise direction, so that when the main shaft 500 drives the first thrust plate 530 to rotate, air flow can enter from the air inlet end of the first grooves 532 more easily, and a local high pressure area is formed at the air outlet end of the first grooves 532, thereby increasing the magnitude of the first thrust force formed between the first thrust plate 530 and the shaft sleeve 600.

Referring to fig. 5, it will be appreciated that the end of the first groove 532 distal from the axis is an inlet end and the end proximal to the axis is an outlet end. The inlet end is located the periphery edge department of first endwall 531 for the first recess 532 of periphery edge entering that first endwall 531 can be followed to the air, thereby is favorable to the first recess 532 of air admission, has increased the air input of first recess 532, and then has increased the area that the outlet end formed local high pressure district, thereby has increased first thrust size, makes rotor system operation more stable, and fan 1000's stability is better.

Referring to fig. 5, it can be understood that the plurality of first grooves 532 have the same structure, which can make the magnitude and direction of the first thrust more stable. One end of the plurality of first grooves 532 facing the axis forms a first reference circle, the diameter of the first reference circle is defined as D21, the number of the first grooves 532 is n, and the width of each first groove 532 on the first reference circle is B, which satisfies: nB/Pi D21 is more than or equal to 20% and less than or equal to 65%, so that the stability of the first thrust is improved. It will be appreciated that the ratio of the plurality of first grooves 532 throughout the first end wall 531 should not be too large or too small. When the occupancy is too large, the equivalent clearance in the first thrust bearing increases and the first thrust force decreases. When the ratio is too small, the local high pressure region generated by the first grooves 532 has limited effect, which is not favorable for forming stable first thrust force and further is not favorable for improving the stability of the rotor system. More preferably, the first groove 532 parameters may be defined as: nB/Pi D21 is more than or equal to 40% and less than or equal to 60%, and the stability of the first thrust can be further ensured.

Referring to fig. 5, it can be understood that the first groove 532 includes a first outer profile and a first inner profile arranged in sequence along the rotation direction of the first thrust disk 530, the tangential angle of the first outer profile at the outer circumferential edge of the first end wall 531 is λ 1, and the tangential angle λ 1 satisfies: the angle is more than or equal to 45 degrees and less than or equal to 1 and less than or equal to 80 degrees, so that the air is favorably and quickly guided into the first groove 532, and a local high-pressure area is generated at the air outlet end of the first groove 532, thereby forming stable first thrust. More preferably, the tangential angle λ 1 may be defined to satisfy: the lambda 1 is more than or equal to 70 degrees and less than or equal to 75 degrees, so that the air inlet of the first groove 532 is smoother, the air inlet amount is larger, and the bearing effect of the thrust bearing is better.

Referring to fig. 6, in the first thrust plate 530 according to another embodiment of the present invention, the first end wall 531 is annular, the plurality of first grooves 532 are disposed on the first end wall 531, and the plurality of first grooves 532 are tapered slots. As shown in fig. 6, it is clear that the width of the inlet end of the first groove 532 is greater than the width of the outlet end of the first groove 532, and the first groove 532 may be configured to be gradually narrowed in the airflow direction. It can be understood that, on the one hand, the width design of the inlet end is great and is favorable to improving the air input of first recess 532, and on the other hand the air is narrowed gradually and is formed local high pressure district at the outlet end after the inlet end gets into, because the air is compressed gradually in first recess 532, can form the local high pressure district that pressure is great at the outlet end, has increased first thrust, has further promoted rotor system's operating stability.

Referring to fig. 7, in the first thrust plate 530 according to another embodiment of the present invention, the first end wall 531 is further provided with a first connection groove 533, the first connection groove 533 is a tapered groove, the first connection groove 533 is provided with a plurality of first connection grooves 533, the plurality of first connection grooves 533 are connected to one end of the plurality of first grooves 532 facing the axis in a one-to-one correspondence manner, and are arranged at an angle with the corresponding first grooves 532, the angle is greater than 0 degree and less than 180 degrees, so that the first connection groove 533 is bent with respect to the first grooves 532, that is, the first connection groove 533 is connected to the end of the first groove 532 in the extending direction. The first recess 532 is also a diagonal slot, thereby forming a fold line slot with the first connecting slot 533 on the first end wall 531. It can be understood that, air is bent to first connecting groove 533 from the end of giving vent to anger after entering from the inlet end, thereby the air current diversion can form the local high pressure district that the area is bigger at the junction of first recess 532 and first connecting groove 533, has further increased the size of first thrust, makes rotor system operation more stable, and fan 1000's stability is better.

Referring to fig. 8, in the first thrust plate 530 according to another embodiment of the present invention, the first end wall 531 is further provided with a first connection groove 533, the first connection groove 533 is a spiral groove, the first connection groove 533 is provided with a plurality of first connection grooves 533, the plurality of first connection grooves 533 are connected to one end of the plurality of first grooves 532 facing the axis in a one-to-one correspondence manner, and are arranged at an angle with the corresponding first grooves 532, the angle is greater than 0 degree and less than 180 degrees, so that the first connection groove 533 is bent relative to the first grooves 532, that is, the first connection groove 533 is connected to the end of the first groove 532 in the extending direction. The first groove 532 is also a helical groove, forming a chevron-shaped groove with the first connecting groove 533 on the first end wall 531. It can be understood that, air is bent to first connecting groove 533 from the end of giving vent to anger after entering from the inlet end, thereby the air current diversion can form the local high pressure district that the area is bigger at the junction of first recess 532 and first connecting groove 533, has further increased the size of first thrust, makes rotor system operation more stable, and fan 1000's stability is better.

As other embodiments, the matching manner of the first groove 532 and the first connecting groove 533 may be various, for example, the first groove 532 is a spiral groove, and the first connecting groove 533 is an inclined groove, the principle and the effect of which are substantially the same as those of the folding groove and the herringbone groove of the above two embodiments, and it can be understood by reference, and no further description is provided herein for avoiding repetition.

It is understood that the first groove 532 and the first connecting groove 533 may be formed by laser machining, etching machining or electric discharge machining, and are not particularly limited herein. The first groove 532 and the first connecting groove 533 may be integrally formed.

As another example, when the first groove 532 is formed on the end wall of the sleeve 600, the first connecting groove 533 is correspondingly formed on the end wall of the sleeve 600.

It is to be understood that the second thrust disk 540 and the opposite end wall of the shaft sleeve 600 according to the embodiment of the present invention have a matching feature, which is substantially the same as the matching feature between the first thrust disk 530 and the opposite end wall of the shaft sleeve 600, and the above embodiment can be referred to for understanding, and the details are not repeated herein for avoiding redundancy.

Referring to fig. 9 and 10, it can be understood that the length of the sleeve 600 is smaller than that of the journal 510 by 8 to 16 μm in the axial direction of the main shaft 500. The first thrust disk 530 and the second thrust disk 540 are respectively positioned and mounted at both ends of the journal 510, so that the clearance between both end surfaces of the sleeve 600 and the first thrust disk 530 and the second thrust disk 540 can be conveniently controlled by defining parameters between the sleeve 600 and the journal 510, so that the internal clearances of both thrust bearings (i.e., the clearance between the first thrust disk 530 and the sleeve 600, and the clearance between the second thrust disk 540 and the sleeve 600) can be controlled to be 4 μm to 8 μm, thereby stabilizing the thrust force of the thrust bearing.

Referring to fig. 9 and 10, it can be understood that the inner diameter of the shaft sleeve 600 is larger than the outer diameter of the shaft journal 510 by a difference of 4 μm to 10 μm, so that when the clearance between the inner peripheral wall of the shaft sleeve 600 and the outer peripheral wall of the shaft journal 510 is controlled in a range of 2 μm to 5 μm, the radial bearing can provide stable radial bearing force, friction between the main shaft 500 and the radial bearing can be reduced, and the stability of rotation of the rotor system can be improved.

Referring to fig. 5 and 9, defining an outer diameter D31 of the journal 510, an end of the first plurality of grooves 532 facing the axis forms a first reference circle having a diameter D21, satisfying: d21 is more than or equal to D31. It can be understood that, by defining the air outlet end of the first groove 532 above the shaft shoulder, a local high pressure region can be formed in the effective fit gap between the first end wall 531 and the end wall of the shaft sleeve 600, stable formation of the first thrust force is ensured, and reduction of the effective acting area between the first groove 532 and the end wall of the shaft sleeve 600 can be avoided, ensuring the magnitude of the first thrust force. Meanwhile, the outer diameter of the shaft sleeve 600 is defined as D41, and the following requirements are met: d21 is not less than D41. It can be understood that, by locating the air outlet end defining the first groove 532 in the effective fit clearance between the first end wall 531 and the end wall of the boss 600, a local high pressure region can be formed in the fit clearance, thereby ensuring the magnitude of the first thrust.

Referring to fig. 9, it can be understood that the outer diameter of the journal 510 is defined as D31, and the outer diameter of the shaft body 520 is defined as D32, so that: D32/D31 is more than or equal to 40% and less than or equal to 80%, so that the mass distribution characteristic of the rotor system is more uniform. The effective acting area of the radial bearing is reduced due to the fact that the proportion parameter is too small, so that enough radial bearing capacity cannot be provided to support a rotor system; the above-mentioned ratio parameter will result in an excessively large outer diameter of the journal 510, and the size of the whole fan 1000 will also increase, which cannot meet the requirement of miniaturization. More preferably, 45% ≦ D32/D31 ≦ 55%, which enables the rotor system to have a better mass distribution and provide sufficient radial load bearing capacity while at the same time providing for a smaller fan 1000. In addition, the outer diameter D32 of the shaft body 520 is limited to be more than or equal to 4mm, so that the strength of the main shaft 500 is ensured, and the main shaft 500 is prevented from being broken in the high-speed rotation process.

Referring to fig. 9, it can be understood that, along the axial direction of the main shaft 500, the length of the journal 510 is L0, and the length of the main shaft 500 is L, which satisfies the following conditions: l0 is more than or equal to 0.2L and less than or equal to 0.8L, so that the effective acting area of the journal 510 and the shaft sleeve 600 is ensured, and the bearing capacity of the radial bearing meets the requirement. It is more preferable to limit 0.4 L.ltoreq.L 0.ltoreq.0.5L.

Referring to fig. 9, it can be understood that a plurality of third grooves 511 are formed in the outer circumferential wall of the journal 510 and spirally extend in the axial direction of the main shaft 500 to form a plurality of spiral grooves, and the air inlet ends of the spiral grooves are located at one end wall of the journal 510 and the air outlet ends are located between two end walls of the journal 510. A plurality of third grooves 511 may be uniformly arranged along the circumferential direction of the journal 510. The peripheral wall of the journal 510 is further provided with a third connection groove 512, the third connection groove 512 is connected to an end of the third groove 511 remote from the end wall of the journal 510 and is arranged at an angle to the third groove 511, the angle being greater than 0 degrees and less than 180 degrees, so that the third connection groove 512 is arranged bent with respect to the third groove 511, i.e. the third connection groove 512 is connected to an end of the third groove 511 in the extending direction. The first connecting groove 533 is also a spiral groove, thereby forming a herringbone groove on the outer circumferential wall of the journal 510 with the third connecting groove 512. It can be understood that, air enters from the air inlet end and then bends to the third connecting groove 512 from the air outlet end, and the airflow changes the direction, so that a local high-pressure area with a larger area can be formed at the connection position of the third groove 511 and the third connecting groove 512, the radial bearing capacity is further increased, the operation of the rotor system is more stable, and the stability of the fan 1000 is better.

Referring to fig. 9, it will be appreciated that one end of the third groove 511 is located in one of the end walls of the journal 510. The third groove 511 is located the one end of the end wall of the axle journal 510 and is the air inlet end, so that the air can enter the third groove 511 from the outer periphery of the end wall of the axle journal 510, the air can enter the third groove 511, the air inlet amount of the third groove 511 is increased, the area of a local high-pressure area formed by an air outlet end is increased, the radial bearing capacity is increased, the rotor system is more stable in operation, and the stability of the fan 1000 is better.

Referring to fig. 9, in the rotor system according to an embodiment of the present invention, one of the outer circumferential wall of the journal 510 and the inner circumferential wall of the sleeve 600 is provided with a plurality of groove sets 513, the plurality of groove sets 513 are spaced apart in the axial direction of the journal 510, and each groove set 513 includes a plurality of third grooves 511 uniformly distributed in the circumferential direction of the journal 510. It will be appreciated that the plurality of groove sets 513 correspond to a plurality of radial bearings, thereby providing a greater and more stable radial load bearing capacity, thereby enabling the rotor system to float relative to the radial bearings, reducing frictional losses between the journal 510 and the shaft sleeve 600, and enabling the rotor system to achieve higher rotational speeds.

Referring to FIG. 9, it will be appreciated that, along the axial direction of spindle 500, the total length of the plurality of groove sets 513 is L1, and in the embodiment shown in FIG. 9, the total length L1 of the plurality of groove sets 513 is equal to the sum of the length L11 of the first groove set and the length L12 of the second groove set, and the length of journal 510 is L0, so that: L1/L0 is more than or equal to 50% and less than or equal to 98%, so that the rotor system can bear enough radial bearing capacity, the running stability of the rotor system is ensured, the amplitude of deflection of the rotor system is reduced, the rotor system can obtain higher rotating speed, and the influence of the fan 1000 on the running of the rotor system in any direction is greatly reduced. More preferably, the limit is 80% to L1/L0 to 98%, so that the radial bearing capacity of the rotor system is larger, the rotation of the rotor system is more stable, and the operation of the fan 1000 is smoother.

Referring to fig. 11, in a blower 1000 according to another embodiment of the present invention, an end wall of the boss 600 opposite to the first end wall 531 is conical, and the first end wall 531 fitted thereto is also conical. Correspondingly, the end wall of the sleeve 600 opposite to the second end wall 541 is also conical, and the second end wall 541 mating therewith is also conical. It can be understood that, when the rotor system is operated at a high speed, the thrust force direction formed by the two thrust bearings formed between the shaft sleeve 600 and the first thrust disk 530 and the second thrust disk 540 is perpendicular to the tapered surface of the shaft sleeve 600, and thus, the thrust force direction can be divided into a radial bearing force and an axial bearing force, and radial support and thrust are realized, so that the operation of the rotor system is more stable.

Referring to fig. 12, in a blower 1000 according to another embodiment of the present invention, an end wall of the boss 600 opposite to the first end wall 531 is spherical, and the first end wall 531 matching therewith is also spherical. Correspondingly, the end wall of the shaft sleeve 600 opposite to the second end wall 541 is also spherical, and the second end wall 541 matched with the shaft sleeve is also spherical. It can be understood that, when the rotor system is operated at a high speed, the thrust force formed by the two thrust bearings formed between the shaft sleeve 600 and the first thrust disk 530 and the second thrust disk 540 is normal to the spherical surface of the shaft sleeve 600, and thus can be decomposed into a radial bearing force and an axial bearing force, so as to achieve radial support and thrust, thereby enabling the rotor system to operate more stably.

Referring to fig. 1, in the cleaning device according to an embodiment of the present invention, the cleaning device may be a handheld vacuum cleaner, a bucket type vacuum cleaner, or a sweeping robot, or may be other cleaning devices. The cleaning device of the embodiment of the present invention includes the blower 1000 of the above embodiment, the support frame 410 fixed to the casing 400 by disposing the shaft sleeve 600, and the rotor system including the impeller 200, the main shaft 500, the first thrust disk 530, the second thrust disk 540, and the rotor 800, wherein the main shaft 500 is rotatably disposed in a radial bearing formed by the shaft sleeve 600, the radial bearing provides a radial bearing force for the rotor system to separate the main shaft 500 from the shaft sleeve 600 during high-speed rotation, so as to reduce the friction force between the main shaft 500 and the shaft sleeve 600; the first thrust disk 530 and the second thrust disk 540 are fixed on the main shaft 500 and form two thrust bearings with opposite acting force directions with the shaft sleeve 600 respectively, under the maximum rotating speed of the fan 1000, the thrust forces of the two thrust bearings are both designed to be the sum of the gravity of a rotor system and the maximum axial gas force of the impeller 200 which are 1.2-2 times, the shaft sleeve 600 can be ensured to be separated from the first thrust disk 530 and the second thrust disk 540, the stability of the rotor system in the axial direction is improved, the influence of the fan 1000 on the operation of the rotor system when working in any direction is reduced, the deflection of the rotor system is effectively reduced, the rotor system can stably operate at the highest rotating speed under various working conditions, and the requirements of miniaturization and light weight of the fan 1000 are ensured; the friction of the rotor system is reduced by adopting the gas bearing, so that the operation of the rotor system is more stable, the performance and the mechanical noise of the fan 1000 are improved, and the stability and the maximum rotating speed of the fan 1000 are improved.

Since the cleaning device adopts all technical solutions of the fan 1000 of the above embodiment, at least all beneficial effects brought by the technical solutions of the above embodiments are achieved, and no further description is given here.

The embodiments of the present invention have been described in detail with reference to the accompanying drawings, but the present invention is not limited to the above embodiments, and various changes can be made within the knowledge of those skilled in the art without departing from the gist of the present invention.

Claims

1. Fan, its characterized in that includes:

a housing provided with a support frame;

the shaft sleeve is fixed on the support frame;

the rotor system comprises an impeller, a main shaft, a first thrust disc, a second thrust disc and a rotor, wherein the main shaft is rotatably arranged in the shaft sleeve, part of the outer peripheral wall of the main shaft is in clearance fit with the inner peripheral wall of the shaft sleeve, the impeller is fixed at one end of the main shaft, the rotor is fixed at the other end of the main shaft, the first thrust disc is fixed on the main shaft and is in clearance fit with the shaft sleeve, a first end wall is arranged at one end, facing the shaft sleeve, of the first thrust disc, a plurality of first grooves are formed in the first end wall or the opposite end wall of the shaft sleeve, the first grooves are circumferentially arranged at intervals along the main shaft, the second thrust disc is fixed on the main shaft and is in clearance fit with the shaft sleeve, a second end wall is arranged at one end, facing the shaft sleeve, of the second thrust disc, and a plurality of second grooves are formed in the second end wall or the opposite end wall of the shaft sleeve, the second grooves are arranged at intervals along the circumferential direction of the main shaft;

the stator is arranged around the periphery of the rotor;

the gravity of the rotor system is G, the diameter of a suction port of the impeller is D11, and the maximum outer diameter of the impeller is D12; the maximum vacuum degree of the fan is P, the thrust of the first thrust disk is F1, the thrust of the second thrust disk is F2 under the maximum rotating speed of the fan, and the following requirements are met: 1.2 ≤ F1/(G + P (π D12)²/4-πD11²/4)) is less than or equal to 2, and 1.2 is less than or equal to F2/(G + P (Pi D12)²/4-πD11²/4））≤2。

2. The fan of claim 1, wherein: the first grooves are arranged on the first end wall, extend towards the axis of the main shaft and incline in the opposite direction of the rotating direction around the first thrust disc.

3. The fan of claim 2, wherein: one end of the first groove, which is far away from the axis, is positioned at the outer peripheral edge of the first end wall.

4. The fan of claim 2, wherein: the first grooves are identical in structure and form a first reference circle towards one end of the axis, the diameter of the first reference circle is D21, the number of the first grooves is n, and the width of each first groove on the first reference circle is B, so that the following conditions are met: nB/Pi D21 is more than or equal to 20 percent and less than or equal to 65 percent.

5. The fan of claim 2, wherein: the first groove comprises a first outer molded line and a first inner molded line which are sequentially arranged along the rotation direction of the first thrust disc, the tangential angle of the first outer molded line at the peripheral edge of the first end wall is lambda 1, and the following requirements are met: λ 1 is more than or equal to 45 degrees and less than or equal to 80 degrees.

6. The fan of claim 2, wherein: the first end wall or the opposite end wall of the shaft sleeve is provided with a plurality of first connecting grooves, and the first connecting grooves are respectively and correspondingly connected to one ends, facing the axis, of the first grooves and are bent relative to the first grooves.

7. The fan of claim 1, wherein: the main shaft comprises a shaft neck and a shaft body, the diameter of the shaft neck is larger than that of the shaft body, the first thrust disc is sleeved on the shaft body and is abutted to one end, facing the impeller, of the shaft neck, and the second thrust disc is sleeved on the shaft body and is abutted to one end, far away from the impeller, of the shaft neck.

8. The fan of claim 7, wherein: the length of the sleeve is less than the length of the journal by a difference of 8 to 16 μm.

9. The fan of claim 7, wherein: the outer diameter of the shaft journal is D31, one end of the first grooves facing the axis of the main shaft forms a first reference circle, the diameter of the first reference circle is D21, the outer diameter of the shaft sleeve is D41, and the following conditions are met: d21 is more than or equal to D31, and D21 is more than or equal to D41.

10. The fan of claim 7, wherein: the outer diameter of the shaft neck is D31, the outer diameter of the shaft body is D32, and the following conditions are met: D32/D31 is more than or equal to 40% and less than or equal to 80%, and D32 is more than or equal to 4 mm.

11. The fan of claim 7, wherein: the second thrust disk is annular, the outer diameter of the second thrust disk is D22, the inner diameter of the stator is D51, the outer diameter of the journal is D31, and the requirements are as follows: 1.3D31 is not less than D22 is not less than 0.98D 51.

12. The fan of claim 7, wherein: the length of the shaft neck is L0, the length of the main shaft is L, and the following conditions are met: l0 is more than or equal to 0.2L and less than or equal to 0.8L.

13. The fan of claim 7, wherein: the periphery wall of axle journal with the internal perisporium clearance fit of axle sleeve, the periphery wall of axle journal with one of them of the internal perisporium of axle sleeve is equipped with many third recesses, and is many the third recess is followed the circumference interval arrangement of main shaft.

14. The fan of claim 13, wherein: many the third recess is located the periphery wall of axle journal just follows the axial spiral of main shaft extends, the periphery wall of axle journal still is equipped with the third spread groove, the third spread groove connect in the third recess is kept away from the one end of the end wall of axle journal, and with the third recess for the setting is bent to the third recess.

15. The fan of claim 1, wherein: the first end wall is circular, conical or spherical.

16. Cleaning apparatus, its characterized in that: comprising a fan according to any of claims 1 to 15.