Blower device and vacuum cleaner

Abstract

To provide a blower with improved waterproofness and dustproofness, and a cleaner including the same.SOLUTION: The blower includes an impeller 1, a motor, and a diffuser. The motor includes a rotor, a stator, and a bearing Br1. The bearing rotatably supports the shaft 211 with respect to the stator. The bearing is accommodated inside the bearing holder 24. The bearing holder has a bearing cylindrical part 241, a bearing top wall part 242, and grease 243. The bearing tube portion is formed in a tubular shape centered on the central axis J and holds the bearing on the radially inner side. The bearing top wall portion is arranged to extend radially inward from an upper end portion of the bearing tubular portion to cover an opening surface of the bearing tubular portion. Grease arranged in a gap A in the radial direction between the bearing top wall part and the shaft is covered with the seal member 41b from the upper side in the axial direction, and the inner end in the radial direction of the seal member contacts the outer peripheral surface of the shaft.SELECTED DRAWING: Figure 6

Description

[Technical Field]

[0001] The present invention relates to a blower device and a vacuum cleaner. [Background technology]

[0002] The vacuum cleaner includes a blower. The blower includes an impeller and a motor. The impeller is rotatable about a central axis extending vertically. The motor rotates the impeller. When the blower is driven, air containing dust and moisture is sucked into the vacuum cleaner (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Chinese Patent Application Publication No. 114825742 Summary of the Invention [Problem to be solved by the invention]

[0004] However, the blower disclosed in Patent Document 1 has a risk of allowing air containing dust and moisture to enter the motor.

[0005] The present invention aims to improve the air blowing efficiency of an air blower. [Means for solving the problem]

[0006] An exemplary blower device of the present invention includes an impeller, a motor, and a diffuser. The impeller is rotatable about a central axis extending vertically. The motor rotates the impeller. The diffuser is disposed on a flow path of fluid flowing out of the impeller and has a plurality of stator vanes arranged circumferentially. The motor includes a rotor, a stator, and a bearing. The rotor has a shaft extending along the central axis and is rotatable about the central axis. The stator is disposed radially outside the rotor and rotates the rotor. The bearing rotatably supports the shaft relative to the stator. The bearing is housed inside a bearing holder. The bearing holder includes a bearing cylindrical portion, a bearing top wall portion, and grease. The bearing cylindrical portion is formed in a cylindrical shape centered on the central axis and holds the bearing radially inside. The bearing top wall portion extends radially inward from an upper end of the bearing cylindrical portion and covers an opening surface of the bearing cylindrical portion. The grease placed in the radial gap between the bearing top wall portion and the shaft is covered from the axially upper side by a seal member, and the radially inner end of the seal member contacts the outer peripheral surface of the shaft.

[0007] An exemplary vacuum cleaner of the present invention includes the above-described blower device. [Effects of the Invention]

[0008] According to an exemplary embodiment of the present invention, it is possible to provide a blower device with improved waterproof and dustproof properties and a vacuum cleaner including the same. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a perspective view of a vacuum cleaner equipped with a blower according to a first embodiment of the present invention. [Figure 2] FIG. 2 is a perspective view of the blower according to the first embodiment of the present invention. [Figure 3] FIG. 3 is a vertical cross-sectional perspective view of the air blower according to the first embodiment of the present invention. [Figure 4] FIG. 4 is a perspective view of a diffuser of the blower according to the first embodiment of the present invention. [Figure 5]FIG. 5 is a vertical cross-sectional perspective view of a diffuser of the blower according to the first embodiment of the present invention. [Figure 6] FIG. 6 is an enlarged vertical cross-sectional view showing the periphery of a bearing of the blower according to the first embodiment of the present invention. [Figure 7] FIG. 7 is an enlarged vertical cross-sectional view showing a part of the diffuser of the blower according to the first embodiment of the present invention. [Figure 8] FIG. 8 is an enlarged vertical cross-sectional view showing the periphery of a bearing of a blower according to a second embodiment of the present invention. [Figure 9] FIG. 9 is an enlarged vertical cross-sectional view showing the periphery of a bearing of a blower according to a third embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the drawings. In this specification, the direction parallel to the central axis J of the blower 10 will be referred to as the "axial direction," the direction perpendicular to the central axis J of the blower 10 will be referred to as the "radial direction," and the direction along the arc centered on the central axis J of the blower 10 will be referred to as the "circumferential direction."

[0011] In addition, in this specification, the shape and positional relationship of each part will be described assuming that the axial direction is the up-down direction and that the diffuser 4 side is the bottom with respect to the impeller 1 in Fig. 2. Note that the up-down direction is a term used merely for the purpose of explanation and does not limit the actual positional relationship or direction in the vacuum cleaner 100.

[0012] First Embodiment <1. Vacuum cleaner configuration> A vacuum cleaner 100 and a blower device 10 according to an exemplary embodiment of the present invention will now be described. Fig. 1 is a perspective view of the vacuum cleaner 100 according to this embodiment. The vacuum cleaner 100 includes a blower device 10. The blower device 10 is mounted on the vacuum cleaner 100 and sucks in air.

[0013] The blower device 10 generates an airflow when driven. When the blower device 10 is driven, air containing dust and moisture is sucked into the vacuum cleaner 100. The vacuum cleaner 100 equipped with the blower device 10 has improved waterproof and dustproof properties, which can prevent abnormalities such as poor suction.

[0014] In this embodiment, the blower device 10 is mounted on a stick-type vacuum cleaner 100, but the blower device 10 can be mounted on various types of vacuum cleaners 100, such as stick-type, robot-type, canister-type, and handheld-type.

[0015] <2. Overall configuration of the blower> 2 is a perspective view of blower 10, and FIG. 3 is a vertical cross-sectional perspective view of blower 10. Blower 10 includes impeller 1, motor 2, fan cover 3, diffuser 4, and substrate cover 5.

[0016] The fan cover 3 covers the impeller 1 from the radially outer side. Specifically, the fan cover 3 has a dome shape that is convex upward. The impeller 1 is disposed radially inside the fan cover 3. The fan cover 3 has a suction port 10A on the central axis J.

[0017] The fan cover 3 has a suction port 10A. The suction port 10A has an opening as the suction port 10A at the center in the radial direction. The blower 10 sucks a fluid through the suction port 10A. The fluid is, for example, a gas such as air containing dust and moisture.

[0018] The impeller 1 is rotatable about a central axis J that extends vertically. The impeller 1 generates an airflow by rotating. The impeller 1 is made of a metal such as aluminum. However, the impeller 1 may also be made of resin.

[0019] The diffuser 4 has a plurality of stator vanes 44. The plurality of stator vanes 44 are arranged on a flow path of the fluid flowing out from the impeller 1. The plurality of stator vanes 44 are arranged at intervals from one another in the circumferential direction. The fluid flowing out from the impeller 1 and heading downward is rectified by the diffuser 4 (specifically, the plurality of stator vanes 44) and discharged from the outlet 10B. The detailed structure of the diffuser 4 will be described later in detail.

[0020] The motor 2 rotates the impeller 1. The motor 2 is a brushless motor of an inner rotor type. The motor 2 includes a rotor 21, a stator 22, bearings Br1 and Br2, a housing 23, and a circuit board 25.

[0021] The rotor 21 is rotatable around the central axis J. The rotor 21 has a shaft 211 and a rotor magnet 212. The shaft 211 extends along the central axis J. The impeller 1 is fixed to the upper end of the shaft 211 via an impeller fixing part 9. When the shaft 211 rotates, the impeller 1 rotates together with the shaft 211.

[0022] The rotor magnet 212 is fixed to the radially outer surface of the shaft 211. The rotor magnet 212 is disposed axially between the bearing Br1 and the bearing Br2. The rotor magnet 212 has N poles and S poles alternately arranged in the circumferential direction.

[0023] The stator 22 is disposed radially outside the rotor 21 and rotates the rotor 21. The stator 22 has a stator core 221, an insulator 222, and coils 223. The stator 22 has coils 223 of multiple phases (three phases: U phase, V phase, and W phase).

[0024] The stator core 221 is an annular magnetic body centered on the central axis J, and is a laminated body in which a plurality of plate-shaped electromagnetic steel sheets are stacked in the axial direction. The stator core 221 is disposed radially outside the rotor magnet 212. The stator core 221 faces the rotor magnet 212 with a gap therebetween in the radial direction.

[0025] Insulator 222 is an insulating member made of resin or the like. Insulator 222 covers at least a portion of stator core 221. Coil 223 is formed by winding a conducting wire around stator core 221 with insulator 222 interposed therebetween.

[0026] The bearings Br1 and Br2 rotatably support the shaft 211 relative to the stator 22. The bearing Br1 is disposed above the rotor magnet 212, and the bearing Br2 is disposed below the rotor magnet 212. The bearing Br1 rotatably supports the shaft 211 on the upper side of the stator 22. The bearing Br2 rotatably supports the shaft 211 on the lower side of the stator 22. The detailed structure of the bearing Br1 will be described in detail later.

[0027] The housing 23 has an upper housing portion 231 and a lower housing portion 232. The upper housing portion 231 covers the stator 22 from the sides and above, and the lower housing portion 232 covers the stator 22 from below. More specifically, the upper housing portion 231 has a housing top wall portion 231a and an upper peripheral wall portion 231b.

[0028] The upper peripheral wall portion 231b is cylindrical and centered on the central axis J. The housing top wall portion 231a is disposed at the upper end of the upper peripheral wall portion 231b and covers the opening surface of the upper peripheral wall portion 231b. The housing top wall portion 231a covers the stator 22 from above and has an upper bearing opening 231c on the central axis J. The upper bearing opening 231c is circular and centered on the central axis J. The bearing Br1 is disposed in the upper bearing opening 231c and is held via a bearing holder 24.

[0029] The shaft 211 protrudes upward beyond the housing top wall portion 231a through the upper bearing opening 231c.

[0030] The bearing holder 24 has a cylindrical shape centered on the central axis J. The bearing holder 24 is fixed to the radially inner surface of the upper bearing opening 231c. In this embodiment, the upper housing portion 231 and the bearing holder 24 are separate members.

[0031] Here, the upper housing portion 231 is made of resin. On the other hand, the bearing holder 24 is preferably made of a material that has higher thermal conductivity than the upper housing portion 231. For example, the bearing holder 24 is made of metal. There are no particular restrictions on the metal material that makes up the bearing holder 24, and aluminum may be used, or stainless steel is preferably used.

[0032] The lower housing portion 232 is a separate member from the upper housing portion 231, and has a housing bottom wall portion 232a and a lower circumferential wall portion 232b. The lower circumferential wall portion 232b is cylindrical and centered on the central axis J, and is connected to the lower end of the upper circumferential wall portion 231b. The housing bottom wall portion 232a is disposed below the stator 22 and is formed in a disk shape. The housing bottom wall portion 232a is disposed radially inward of the lower circumferential wall portion 232b, and has a lower bearing opening 232c on the central axis J. The bearing Br2 is disposed in and held in the lower bearing opening 232c.

[0033] The circuit board 25 is disposed below the lower housing portion 232. The circuit board 25 is electrically connected to the stator 22. The stator 22 receives power from the circuit board 25. As a result, power is supplied to the coil 223.

[0034] The board cover 5 is formed in a cylindrical shape with a bottom, and covers the lower side of the circuit board 25. The board cover 5 is connected to the lower end of the lower housing portion 232.

[0035] <3. Detailed configuration of the diffuser> FIG. 4 is a perspective view of the diffuser 4, and FIG. 5 is a perspective view of the diffuser 4 in vertical section. The diffuser 4 has a diffuser top wall portion 41, an inner cylinder portion 42, an outer cylinder portion 43, and stator vanes 44. The diffuser top wall portion 41 is formed in a circular plate shape and has an opening 41a on the central axis J. The inner cylinder portion 42 extends cylindrically downward from the radially outer edge of the diffuser top wall portion 41. The outer cylinder portion 43 is disposed radially outward from the inner cylinder portion 42 at a distance. Each stator vane 44 is disposed radially between the inner cylinder portion 42 and the outer cylinder portion 43 and connects the inner cylinder portion 42 and the outer cylinder portion 43.

[0036] <4. Detailed configuration of bearing and bearing holder> Fig. 6 is an enlarged longitudinal cross-sectional view of the bearing Br1 and its surroundings, and Fig. 7 is an enlarged longitudinal cross-sectional view of the radially inner end of the diffuser. The bearing Br1 has balls 61, an inner ring 62, and an outer ring 63. The inner ring 62 is formed into a cylindrical shape extending in the axial direction and surrounding the shaft 211. The outer ring 63 is disposed radially outward from the inner ring 62 at a distance and is also formed into a cylindrical shape extending in the axial direction. The radially inner surface of the inner ring 62 is fixed to the outer peripheral surface of the shaft 211. The radially outer surface of the outer ring 63 is fixed to the radially inner surface of the bearing holder 24.

[0037] The balls 61 are rotatably held between an inner ring 62 and an outer ring 63, and a plurality of balls 61 are arranged in the circumferential direction.

[0038] The bearing Br1 is housed inside the bearing holder 24. The bearing holder 24 is composed of a bearing cylindrical portion 241, a bearing top wall portion 242, and grease 243. The bearing cylindrical portion 241 is formed in a cylindrical shape centered on the central axis J, and holds the bearing Br1 on its radially inner side. The bearing top wall portion 242 extends radially inward from the upper end of the bearing cylindrical portion 241, and covers the opening surface of the bearing cylindrical portion 241.

[0039] The bearing top wall portion 242 is formed in a disk shape and has a through hole 242a that penetrates in the axial direction on the central axis J. As a result, the radially inner end of the bearing top wall portion 242 (the periphery of the through hole 242a) and the outer peripheral surface of the shaft 211 face each other with a radial gap interposed therebetween. At this time, the radially inner end of the bearing top wall portion 242 overlaps with the bearing Br1 in the axial direction. In this embodiment, the radially inner end of the bearing top wall portion 242 overlaps with the inner ring 62 of the bearing Br1 in the axial direction, but may also overlap with the ball 61 or the outer ring 63 in the axial direction.

[0040] The diffuser top wall portion 41 also has a protrusion 41c protruding from the lower surface. The protrusion 41c comes into contact with the upper surface of the bearing cylindrical portion 241. As a result, an axial gap A is formed between the radially inner end of the diffuser top wall portion 41 and the bearing top wall portion 242. Note that multiple protrusions 41c may be provided in the circumferential direction, or may be formed in an annular shape.

[0041] The grease 243 is a viscous liquid and has lubricating properties. In this embodiment, the grease 243 is filled into the gap A. The grease 243 is also disposed in the radial gap between the bearing top wall portion 242 and the shaft 211 and in the radial gap between the diffuser top wall portion 41 and the shaft 211.

[0042] The grease 243 is covered from the axially upper side by the radially inner end 41b of the diffuser top wall portion 41, and the radially inner end of the radially inner end 41b of the diffuser top wall portion 41 contacts the outer peripheral surface of the shaft 211. In other words, the periphery of the opening 41a contacts the outer peripheral surface of the shaft 211, and the radially inner end 41b of the diffuser top wall portion 41 forms a sealing member.

[0043] It is preferable that the entire periphery of the opening 41a contacts the outer circumferential surface of the shaft 211, but only a portion of the periphery of the opening 41a may contact the outer circumferential surface of the shaft 211.

[0044] Furthermore, the radially inner end (sealing member) 41b of the diffuser top wall portion 41 has an axial thickness that decreases radially inward (see FIG. 7). This reduces the contact resistance between the radially inner end (sealing member) 41b of the diffuser top wall portion 41 and the shaft 211, thereby reducing the power consumption of the motor 2.

[0045] The radially inner end (sealing member) 41b of the diffuser top wall portion 41 that contacts the shaft 211 blocks air containing dust and moisture, thereby reducing the intrusion of air containing dust and moisture into the bearing Br1 and the motor 2. Furthermore, the grease 243 disposed in the radial gap between the bearing top wall portion 242 and the shaft 211 blocks air containing dust and moisture, further reducing the intrusion of air containing dust and moisture into the bearing Br1 and the motor 2. This makes it possible to provide a blower 10 with improved waterproof and dustproof properties.

[0046] Furthermore, even if the grease 243 arranged in the radial gap between the bearing top wall portion 242 and the shaft 211 is worn away by the rotation of the bearing Br1, the grease 243 filled in the gap A is replenished in the radial gap between the bearing top wall portion 242 and the shaft 211. This further reduces the intrusion of air containing dust and moisture into the bearing Br1 and the motor 2.

[0047] Furthermore, the radially inner end of the bearing top wall portion 242 overlaps with the bearing Br1 in the axial direction, and a small radial gap is formed between the bearing top wall portion 242 and the shaft 211. This further reduces the intrusion of air containing dust and moisture into the bearing Br1 through the radial gap between the bearing top wall portion 242 and the shaft 211.

[0048] In this embodiment, the radially inner end 41b of the diffuser top wall 41 is configured as a seal member. By configuring the seal member from a part of the diffuser 4, the number of parts can be reduced, thereby cutting the manufacturing cost of the blower 10. Furthermore, because the radially inner end of the diffuser top wall 41 contacts the outer peripheral surface of the shaft, the diffuser 4 can be easily assembled coaxially with the shaft 211. This improves the manufacturing efficiency of the blower 10.

[0049] Second Embodiment Next, a second embodiment of the present invention will be described. Fig. 8 is an enlarged longitudinal sectional view showing the periphery of a bearing Br1 of a blower 10 according to the second embodiment. For ease of explanation, the same parts as those of the first embodiment shown in Figs. 1 to 7 are denoted by the same reference numerals. The second embodiment differs from the first embodiment in that the seal member is formed by a washer 26. Furthermore, the radial inner end of the diffuser top wall portion 41 (the periphery of the opening 41a) is not in contact with the outer circumferential surface of the shaft 211. The other parts are the same as those of the first embodiment.

[0050] The washer 26 is annular and surrounds the shaft 211 , and the radially inner end of the washer 26 contacts the outer circumferential surface of the shaft 211 .

[0051] Furthermore, the washer 26 is sandwiched in the axial direction between the radially inner end of the diffuser top wall portion 41 and the bearing top wall portion 242. This allows the washer 26 to be easily fixed between the diffuser top wall portion 41 and the bearing top wall portion 242.

[0052] In this embodiment, the diffuser top wall portion 41 has a protrusion 41d that protrudes from the lower surface at the radially inner end portion. The protrusion 41d comes into contact with the upper surface of the washer 26. This allows the washer 26 to be more stably fixed by sandwiching it between the diffuser top wall portion 41 and the bearing top wall portion 242 in the axial direction. Note that multiple protrusions 41d may be provided in the circumferential direction, or may be formed in an annular shape.

[0053] At this time, a contact position P1 between the washer 26 and the diffuser top wall portion 41 is positioned radially shifted from a contact position P2 between the washer 26 and the bearing top wall portion 242. This allows the washer 26 to be sandwiched between the diffuser top wall portion 41 and the bearing top wall portion 242 in the axial direction and fixed more stably.

[0054] By covering the radial gap between the bearing top wall portion 242 and the shaft 211 with the washer 26 from above in the axial direction, it is possible to easily reduce the intrusion of air containing dust and moisture into the inside of the bearing Br1 and the motor 2.

[0055] The washer 26 is preferably made of, for example, a fluorine-based resin, which can reduce wear and deterioration of the radially inner end of the washer 26 that comes into contact with the shaft 211.

[0056] The diffuser top wall portion 41 and the bearing top wall portion 242 are disposed radially outside the washer 26, facing each other in the axial direction with a gap A interposed therebetween. By forming the gap A on the radially outside of the washer 26, the position of the washer 26 can be adjusted in the radial direction, thereby improving the assembly accuracy of the washer 26.

[0057] Third Embodiment Next, a third embodiment of the present invention will be described. Fig. 9 is an enlarged longitudinal cross-sectional view of the bearing Br1 and its surroundings in a blower 10 according to the third embodiment. For ease of explanation, the same parts as those in the second embodiment shown in Fig. 8 are denoted by the same reference numerals. The third embodiment differs from the second embodiment in that the washer 26 is axially sandwiched between the radially inner end of the diffuser top wall 41 and the bearing top wall 242 via an elastic member 50 such as rubber.

[0058] The diffuser top wall 41 does not have a convex portion 41c or a protruding portion 41d, but has an annular recess 41e recessed upward from the lower surface. The housing top wall 231a has a rib 231d protruding upward from the periphery of the upper bearing opening 231c. The rib 231d is formed in an annular shape and is in contact with the top surface of the recess 41e. The recess 41e and the rib 231d are located radially outward of the elastic member 50. Other parts are the same as those in the second embodiment.

[0059] By providing the elastic member 50, the washer 26 can be more stably fixed by being sandwiched in the axial direction between the diffuser top wall portion 41 and the bearing top wall portion 242. In addition, it is possible to further reduce the intrusion of air containing dust and moisture into the bearing Br1 from the contact surface between the washer 26 and the diffuser top wall portion 41.

[0060] More specifically, the elastic member 50 is in the shape of an annular plate surrounding the shaft 211 and has elastic ribs 51 and 52. The elastic rib 51 protrudes from the upper surface of the elastic member 50 and extends in an annular shape surrounding the shaft 211. The elastic rib 52 protrudes from the upper surface of the elastic member 50 and extends in annular shape surrounding the shaft 211. The outer peripheral surface of the shaft 211 and the inner peripheral surface of the elastic member 50 face each other in the radial direction with a gap interposed therebetween.

[0061] The elastic member 50 is sandwiched in the axial direction between the radially outer end of the washer 26 and the radially inner end of the diffuser top wall portion 41. At this time, the elastic rib 51 contacts the lower surface of the diffuser top wall portion 41, and the elastic rib 52 contacts the upper surface of the washer 26. By providing the elastic ribs 51, 52, the airtightness between the diffuser top wall portion 41 and the elastic member 50 and the airtightness between the elastic member 50 and the washer 26 can be improved.

[0062] <5.Other> The above describes an embodiment of the present invention. However, the scope of the present invention is not limited to the above embodiment. The present invention can be implemented with various modifications without departing from the spirit of the invention. Furthermore, the above-described embodiments can be combined in any suitable manner. For example, in the above embodiment, the upper housing portion 231 and the bearing holder 24 are formed as separate members, but the upper housing portion 231 and the bearing holder 24 may be formed integrally.

[0063] <6. Notes> As described above, the blower (10) according to one aspect of the present disclosure includes an impeller (1) rotatable about a central axis (J) extending vertically, a motor (2) for rotating the impeller, and a diffuser (4) having a plurality of stator vanes (44) arranged in a circumferential direction and disposed on a flow path of a fluid flowing out of the impeller, the motor having a shaft (211) extending along the central axis, a rotor (21) rotatable about the central axis, a stator (22) disposed radially outward of the rotor and rotating the rotor, and a bearing (Br1) for rotatably supporting the shaft relative to the stator. The bearing is accommodated inside a bearing holder (24), the bearing holder is formed in a cylindrical shape centered on the central axis, and has a bearing cylindrical portion (241) that holds the bearing on its radially inner side, a bearing top wall portion (242) that extends radially inward from an upper end of the bearing cylindrical portion and covers an opening surface of the bearing cylindrical portion, and grease (243) that is placed in a radial gap between the bearing top wall portion and the shaft, the grease being covered from an axially upper side by a sealing member (41), and the radially inner end of the sealing member contacts the outer peripheral surface of the shaft (first configuration).

[0064] In the first configuration, the sealing member may have an axial thickness that decreases toward the radially inner side (second configuration).

[0065] In the first or second configuration, the diffuser may include a cylindrical diffuser inner cylinder portion (241) that connects radially inner ends of the plurality of stator vanes and extends in the axial direction around the central axis, and a diffuser top wall portion (242) that extends radially inward from an axial upper end of the diffuser inner cylinder portion and covers an opening surface of the diffuser inner cylinder portion, and the radially inner end of the diffuser top wall portion may form the sealing member (third configuration).

[0066] In addition, in any of the first to third configurations, the grease may be filled in an axial gap (A) formed between the radially inner end of the diffuser top wall portion and the bearing top wall portion (fourth configuration).

[0067] In any one of the first to fourth configurations, the radially inner end of the bearing ceiling wall portion may be configured to overlap the bearing in the axial direction (fifth configuration).

[0068] In the first or second configuration, the sealing member may be configured as an annular washer (26) surrounding the shaft (sixth configuration).

[0069] In the sixth configuration, the diffuser may include a cylindrical diffuser inner cylinder portion (241) that connects radially inner ends of the plurality of stator vanes and extends in the axial direction around the central axis, and a diffuser top wall portion (242) that extends radially inward from an axial upper end of the diffuser inner cylinder portion and covers an opening surface of the diffuser inner cylinder portion, and the washer may be configured to be sandwiched in the axial direction between the radially inner end of the diffuser top wall portion and the bearing top wall portion (seventh configuration).

[0070] In the seventh configuration, the washer may be configured to be sandwiched in the axial direction between the radially inner end of the diffuser top wall portion and the bearing top wall portion via an elastic member (eighth configuration).

[0071] In addition, in the seventh or eighth configuration, the contact position (P1) between the washer and the diffuser ceiling wall portion may be configured to be radially shifted from the contact position (P2) between the washer and the bearing ceiling wall portion (ninth configuration).

[0072] In addition, in any of the seventh to ninth configurations, the diffuser top wall portion and the bearing top wall portion may be arranged radially outside the washer, facing each other in the axial direction with a gap (A) interposed therebetween (tenth configuration).

[0073] In any one of the sixth to tenth configurations, the washer may be made of a fluorine-based resin (eleventh configuration).

[0074] Also, a vacuum cleaner (twelfth configuration) including the air blower device of any one of the first to eleventh configurations. [Industrial Applicability]

[0075] The present invention can be used, for example, in a blower device mounted on a vacuum cleaner or the like. [Explanation of symbols]

[0076] 1 impeller 2 motors 3 Fan cover 4 Diffuser 5 Board cover 9 Impeller fixing part 10. Blower 10A suction port 10B Outlet 21 rotor 22 Stator 23 Housing 24 Bearing holder 25 Circuit Board 26 Washer 41 Diffuser ceiling wall 41a opening 41b Radial inner end 41c Convex part 41d Protrusion 41e Recess 42 Inner cylinder 43 Outer cylinder 44 Stator blade 50 Elastic member 51, 52 Elastic rib 61 Ball 62 Inner circle 63 Outer ring 100 vacuum cleaner 211 Shaft 212 rotor magnet 221 Stator Core 222 Insulator 223 Coil 231 Upper housing part 231a Housing top wall 231b Upper peripheral wall 231c Upper bearing opening 231d Rib 232 Lower housing part 232a Housing bottom wall 232b Lower peripheral wall 232c Lower bearing opening 241 Bearing cylinder 242 Bearing top wall 242a Through hole 243 Grease A Gap Br1, Br2 bearings J center axis P1 contact position P2 contact position

Claims

1. an impeller that is rotatable around a central axis that extends vertically; a motor that rotates the impeller; a diffuser disposed on a flow path of the fluid flowing out of the impeller and having a plurality of stator vanes arranged in a circumferential direction, The motor a rotor having a shaft extending along the central axis and rotatable about the central axis; a stator disposed radially outside the rotor and configured to rotate the rotor; a bearing that rotatably supports the shaft relative to the stator, The bearing is accommodated inside a bearing holder, The bearing holder includes: a cylindrical bearing portion formed in a cylindrical shape centered on the central axis and holding the bearing on its radially inner side; a bearing top wall portion that extends radially inward from an upper end portion of the cylindrical bearing portion and covers an opening surface of the cylindrical bearing portion; grease disposed in a radial gap between the bearing top wall portion and the shaft, The grease is covered with a seal member from the axially upper side, The sealing member has a radially inner end that contacts an outer peripheral surface of the shaft.

2. The blower device according to claim 1 , wherein the sealing member has an axial thickness that decreases toward the radially inner side.

3. The diffuser is a cylindrical diffuser inner cylinder portion that connects radially inner ends of the plurality of stator vanes and extends in the axial direction while surrounding the central axis; a diffuser top wall portion extending radially inward from an axial upper end of the diffuser inner cylindrical portion and covering an opening surface of the diffuser inner cylindrical portion, The blower device according to claim 1 , wherein a radially inner end of the diffuser top wall portion constitutes the sealing member.

4. The blower device according to claim 3 , wherein the grease is filled in an axial gap formed between a radially inner end of the diffuser top wall portion and the bearing top wall portion.

5. The blower device according to claim 3 or 4, wherein a radially inner end of the bearing top wall portion overlaps with the bearing in the axial direction.

6. The blower device according to claim 1 or 2, wherein the sealing member is an annular washer surrounding the shaft.

7. The diffuser is a cylindrical diffuser inner cylinder portion that connects radially inner ends of the plurality of stator vanes and extends in the axial direction while surrounding the central axis; a diffuser top wall portion extending radially inward from an axial upper end of the diffuser inner cylindrical portion and covering an opening surface of the diffuser inner cylindrical portion, The blower device according to claim 6 , wherein the washer is axially sandwiched between a radially inner end of the diffuser top wall portion and the bearing top wall portion.

8. The blower device according to claim 7 , wherein the washer is axially sandwiched between a radially inner end of the diffuser top wall portion and the bearing top wall portion via an elastic member.

9. The blower device according to claim 7 , wherein a contact position between the washer and the diffuser top wall portion is radially shifted from a contact position between the washer and the bearing top wall portion.

10. The blower device according to claim 7 , wherein the diffuser top wall portion and the bearing top wall portion are disposed radially outward of the washer, facing each other in the axial direction with a gap interposed therebetween.

11. The blower according to claim 6, wherein the washer is made of a fluorine-based resin.

12. A vacuum cleaner comprising the air blower device according to claim 1 or 2.

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