Motor

Abstract

A motor is provided. A motor according to one aspect of the present specification comprises: a housing; a first bearing disposed radially inside the housing; a rotary shaft rotatably coupled to the first bearing; a rotor coupled to the rotary shaft and disposed below the first bearing; a stator assembly disposed radially outside the rotor; an impeller coupled to the rotary shaft and disposed below the rotor; a diffuser coupled to the housing and disposed below the impeller; a second bearing which is coupled to the central region of the diffuser and to which the rotary shaft is rotatably coupled; and a bearing holder disposed between the first bearing and the housing in the radial direction, wherein at least a portion of the lower surface of the first bearing is supported by the bearing holder, and at least a portion of the upper surface of the second bearing is supported by the diffuser.

Description

motor

[0001] This specification relates to a motor, and more specifically, to a motor for a vacuum cleaner that performs cleaning by sucking up or wiping away dust or foreign matter from an area to be cleaned.

[0002] In general, a vacuum cleaner is a home appliance that sucks up foreign substances such as dust and collects them in a separate dust collection unit installed inside the main body.

[0003] Specifically, vacuum cleaners require high suction power to effectively suck up foreign substances, and the strength of this suction power is proportional to the motor's rotational speed. In other words, the higher the motor's rotational speed, the faster the fan connected to the motor rotates, increasing the suction power of foreign substances.

[0004] Typically, a vacuum cleaner motor is a device that obtains rotational power from electrical energy and includes a stator and a rotor. The rotor can be rotated by electromagnetic interaction with the stator.

[0005] Fig. 1 is a perspective view of a motor according to the prior art. Fig. 2 is a drawing showing a support method of a cantilever structure of a motor according to the prior art.

[0006] Referring to FIGS. 1 and 2, a motor (10) for a vacuum cleaner according to the prior art includes a first housing (11), a rotation shaft (13) rotatably coupled to the first housing (11), a rotor (14) coupled to the rotation shaft (13), a stator assembly (15) coupled to the first housing (11), an impeller (16) coupled to a lower region of the rotation shaft (13), a second housing (12) surrounding the impeller (16) and coupled to the first housing (11), and a diffuser (17) coupled to the second housing (12).

[0007] The impeller (16) is formed in a conical shape with an open center, and the diameter becomes smaller as it goes upward in the axial direction, and a plurality of blades protruding radially outward are formed on the radially outer surface of the impeller (16).

[0008] The second housing (12) is designed to have an inner diameter that decreases as it goes upward in the axial direction in the area overlapping the impeller (16) in the radial direction, thereby facilitating the flow of air flowing into the second housing (12).

[0009] In this case, a certain gap must be formed between the second housing (12) and the impeller (16) to ensure smooth air flow while preventing collision between the impeller (16) and the second housing (12).

[0010] However, since the rotor (14) is arranged between the first bearing (18) and the second bearing (19), and the impeller (16) has a cantilever structure arranged below the second bearing (19), secondary press-fitting of the rotation shaft (13) to secure a constant gap between the impeller (16) and the second housing (12) is impossible.

[0011] Due to this, there was a problem of interference occurring between the blades of the impeller (16) and the outer surface of the second housing (12) when the impeller (16) rotated at high speed.

[0012] The problem to be solved by this specification is to provide a motor that can enable vertical movement of a bearing and a rotational shaft while forming outward preload on both axial sides of a first bearing and a second bearing.

[0013] In addition, the problem that this specification seeks to solve is to provide a motor that can set an accurate gap between the inner surface of the second housing and the impeller blades, and can secure reliability by maintaining a constant gap between the inner surface of the second housing and the impeller blades even during high-speed operation.

[0014] In addition, the problem to be solved by this specification is to provide a motor that can increase the durability life of bearings by maintaining alignment between bearings due to the careful effect of an elastic member while maintaining the balance of the rotor.

[0015] In addition, the problem to be solved by this specification is to provide a motor that can reduce noise generated by rotor rotation by having an impeller having a support structure at both ends positioned between two bearings.

[0016] In addition, the problem that this specification seeks to solve is to provide a motor that can prevent interference between impeller blades and the inner surface of the housing.

[0017] According to one aspect of the present specification for achieving the above object, a motor comprises a housing, a first bearing disposed radially inwardly of the housing, a rotational shaft rotatably coupled to the first bearing, a rotor coupled to the rotational shaft and disposed below the first bearing, a stator assembly disposed radially outwardly of the rotor, an impeller coupled to the rotational shaft and disposed below the rotor, a diffuser coupled to the housing and disposed below the impeller, a second bearing coupled to a central region of the diffuser and to which the rotational shaft is rotatably coupled, a bearing holder disposed radially between the first bearing and the housing, and an elastic member disposed axially between the bearing holder and the housing.

[0018] In this case, at least a part of the lower surface of the first bearing may be supported by the bearing holder, and at least a part of the upper surface of the second bearing may be supported by the diffuser.

[0019] Through this, it is possible to enable vertical movement of the bearing and the rotational axis while forming outward preload on both sides of the axial direction on the first and second bearings. In addition, an accurate gap between the inner surface of the second housing and the impeller blades can be set, and a constant gap between the inner surface of the second housing and the impeller blades can be maintained even during high-speed operation, thereby ensuring reliability. In addition, while maintaining the balance of the rotor, the bearings can be aligned due to the balancing effect of the elastic member, thereby extending the bearing life.

[0020] Additionally, at least a portion of the rotor, at least a portion of the impeller, and at least a portion of the diffuser may be disposed between the first bearing and the second bearing.

[0021] This allows the impeller to have a support structure at both ends positioned between two bearings, thereby reducing the noise generated by the rotor rotation.

[0022] The above impeller may be located downstream of the flow path generated by the rotation of the impeller.

[0023] Additionally, the inner ring of the first bearing may be coupled to the rotational axis, and the lower surface of the outer ring of the first bearing may be supported by the bearing holder.

[0024] In addition, the bearing holder may include a first horizontal portion supporting a lower surface of an outer ring of the first bearing, a first vertical portion extending axially upward from a radially outer region of the first horizontal portion and contacting an outer surface of the outer ring of the first bearing, a second horizontal portion extending radially outward from an upper region of the first vertical portion, and a second vertical portion extending axially downward from a radially outer region of the second horizontal portion.

[0025] Additionally, the housing may include a first support portion extending radially inward from a lower region of the inner surface facing the first bearing, and a step portion formed between the first support portion and the inner surface.

[0026] In this case, the upper surface of the elastic member may contact the lower surface of the second horizontal portion, and the lower surface of the elastic member may contact the upper surface of the first support portion.

[0027] Additionally, the inner ring of the second bearing may be coupled to the rotation axis, and the upper surface of the outer ring of the second bearing may be supported by the diffuser.

[0028] Additionally, the diffuser includes a second support portion extending radially inwardly from an upper region of the inner surface, an upper surface of an outer ring of the second bearing is supported by the second support portion, and an outer surface of the outer ring of the second bearing can be in contact with the inner surface of the diffuser.

[0029] Additionally, the upper region of the impeller may directly face the stator assembly.

[0030] Additionally, the housing may include a first housing and a second housing that surrounds the impeller and is coupled to the first housing, the first bearing may be disposed radially inward on an inner surface of an upper region of the first housing, and the diffuser may be disposed in a lower region of the second housing.

[0031] According to the present specification, a motor can be provided that enables vertical movement of a bearing and a rotational shaft while forming an outward preload on both sides of the first bearing and the second bearing in the axial direction.

[0032] In addition, the present specification provides a motor capable of setting an accurate gap between the inner surface of the second housing and the impeller blades, and ensuring reliability by maintaining a constant gap between the inner surface of the second housing and the impeller blades even during high-speed operation.

[0033] In addition, the present specification provides a motor that can maintain alignment between bearings due to the care effect of an elastic member while maintaining the balance of the rotor, thereby increasing the durability life of the bearings.

[0034] In addition, the present specification provides a motor capable of reducing noise generated by rotor rotation by having an impeller having a support structure at both ends positioned between two bearings.

[0035] Additionally, the present specification provides a motor capable of preventing interference between impeller blades and the inner surface of the housing.

[0036] Figure 1 is a perspective view of a motor according to the prior art.

[0037] Fig. 2 is a drawing showing a support method of a cantilever structure of a motor according to a conventional technology.

[0038] FIG. 3 is a perspective view of a motor according to one embodiment of the present specification.

[0039] Figure 4 is an exploded perspective view of a motor according to one embodiment of the present specification.

[0040] FIG. 5 is a cross-sectional view of a motor according to one embodiment of the present specification.

[0041] Figure 6 is an enlarged view of part A of Figure 5.

[0042] Figure 7 is an enlarged view of part B of Figure 5.

[0043] FIG. 8 is a drawing showing a double-end support structure of a motor according to one embodiment of the present specification.

[0044] Hereinafter, some embodiments of the present specification will be described in detail with reference to exemplary drawings. When designating components in each drawing, it should be noted that, where possible, identical components are given the same reference numerals even if they are shown in different drawings. In addition, when describing embodiments of the present specification, if a detailed description of a related known configuration or function is judged to hinder understanding of the embodiments of the present specification, the detailed description will be omitted.

[0045] Fig. 3 is a perspective view of a motor according to one embodiment of the present specification. Fig. 4 is an exploded perspective view of a motor according to one embodiment of the present specification. Fig. 5 is a cross-sectional view of a motor according to one embodiment of the present specification. Fig. 6 is an enlarged view of portion A of Fig. 5. Fig. 7 is an enlarged view of portion B of Fig. 5. Fig. 8 is a drawing showing a double-end support structure of a motor according to one embodiment of the present specification.

[0046] Referring to FIGS. 3 to 8, a motor (20) according to one embodiment of the present specification may include a housing (100), a rotation shaft (200), a rotor (300), a stator assembly (400), an impeller (500), a diffuser (600), a first bearing (700), a bearing holder (800), an elastic member (900), and a second bearing (1000). However, some of these configurations may be excluded, and additional configurations are not excluded.

[0047] The motor (20) may be a suction motor used in a vacuum cleaner. The motor (20) may generate suction force to cause external dust to be introduced into the vacuum cleaner. The arrangement of the detailed configuration of the motor (20) may be arranged to form a reverse flow path based on the rotation shaft (200). Specifically, the impeller (500) may be arranged downstream of the flow path generated by the rotation of the impeller (500) coupled to the rotation shaft (200). In other words, air outside the motor (20) is sucked into the inside of the motor (20) according to the rotation of the impeller (500), and the flow path through which the air flows inside the motor (20) may be formed by sequentially passing through the first housing (110), the stator assembly (400), the impeller (500), and the diffuser (600). Through this, the heat dissipation effect for heat generated due to electromagnetic interaction between the rotor (300) and the stator assembly (400) can be improved compared to a motor arranged in a forward flow path.

[0048] The housing (100) may include a first housing (110) and a second housing (120). In one embodiment of the present specification, the first housing (110) and the second housing (120) are described as being separately coupled, but the present invention is not limited thereto and the first housing (110) and the second housing (120) may be formed integrally.

[0049] The first housing (110) may include a bearing housing in which a bearing holder (800) is arranged, and a plurality of legs extending axially downward from a radially outer region of the bearing housing. The plurality of legs may be spaced apart from each other in the circumferential direction. The legs of the first housing (110) may be coupled to the second housing (120). Here, the bearing housing may be referred to as the upper region of the first housing (110).

[0050] The first housing (110) may include a first support portion (114) extending radially inward from a lower region of the inner surface (112) facing the first bearing (700), and a step portion (116) formed between the first support portion (114) and the inner surface (112).

[0051] In one embodiment of the present specification, the axial upper part or above means the 'A' direction based on FIG. 4, and the axial lower part or below means the 'B' direction based on FIG. 4.

[0052] The second housing (120) can be coupled to the first housing (110). The second housing (120) can surround the impeller (500). The second housing (120) can be formed in a spherical shape. The second housing (120) can include a lower region that surrounds the impeller (500) and whose inner diameter decreases as it goes axially upward, and an upper region that is coupled to the first housing (110).

[0053] The rotational shaft (200) can be rotatably coupled to the first housing (110). The rotational shaft (200) can be rotatably coupled to the first housing (110) via a first bearing (700). The rotational shaft (200) can extend in a vertical direction. The rotational shaft (200) can be formed in a cylindrical shape. The rotational shaft (200) can rotate in one direction or the other direction by the rotation of the rotor (300). The rotational shaft (200) can be rotatably coupled to the diffuser (600). The rotational shaft (200) can be rotatably coupled to the diffuser (600) via a second bearing (1000).

[0054] The rotor (300) can be coupled to the rotation shaft (200). The rotor (300) can be positioned below the first bearing (700). The rotor (300) can be positioned radially inward of the stator assembly (400). The rotor (300) can face the stator assembly (400). The rotor (300) can rotate in one direction or the other by electromagnetic interaction with the stator assembly (400).

[0055] The rotor (300) may be positioned between the first bearing (700) and the second bearing (1000) in the axial or vertical direction. The rotor (300) may be positioned axially only in a portion of the rotor (300) between the first bearing (700) and the second bearing (1000). Alternatively, the entire rotor (300) may be positioned axially between the first bearing (700) and the second bearing (1000).

[0056] The stator assembly (400) can be coupled to the housing (100). The stator assembly (400) can be coupled to the first housing (110) and / or the second housing (120). The stator assembly (400) can be disposed in an internal space created by the first housing (110) and the second housing (120). The stator assembly (400) can be disposed radially outside the rotor (300). The stator assembly (400) can include a stator core facing the rotor (300), a coil wound around the stator core, and an insulator formed of an insulating material and surrounding the stator core.

[0057] The impeller (500) may be coupled to the rotation shaft (200). The impeller (500) may rotate in one direction or the other depending on the rotation of the rotation shaft (200). The impeller (500) may be disposed below the rotor (300). The impeller (500) may be disposed between the stator assembly (400) and the second bearing (1000). The diameter of the impeller (500) may decrease as it goes upward in the axial direction. The impeller (500) may be formed in a conical shape with an open center overall. A plurality of impeller blades may be formed on the radially outer surface of the impeller (500) to protrude radially outward and be spaced apart from each other in the circumferential direction.

[0058] At least a portion of the impeller (500) may be positioned axially or vertically between the first bearing (700) and the second bearing (1000). Specifically, a central region of the impeller (500) coupled with the rotational axis (200) may be positioned axially between the first bearing (700) and the second bearing (1000).

[0059] The second housing (120) is designed to have an inner diameter that decreases from the lower region of the second housing (120) toward the upper region in the axial direction in the area overlapping the impeller (500) in the radial direction, thereby facilitating the flow of air flowing into the second housing (120). The lower region of the second housing (120) may be formed in a bell mouth shape.

[0060] In this case, in order to prevent collision between the impeller blades of the impeller (500) and the inner surface of the second housing (120) while ensuring smooth air flow, it is preferable that a certain gap be formed between the inner surface of the second housing (120) and the impeller blades of the impeller (500).

[0061] The diffuser (600) can be coupled to the second housing (120). The diffuser (600) can be positioned below the impeller (500). A rotational shaft (200) can be rotatably coupled to the diffuser (600).

[0062] At least a portion of the diffuser (600) may be positioned axially or vertically between the first bearing (700) and the second bearing (1000). Specifically, the second support (604) of the diffuser (600) may be positioned axially between the first bearing (700) and the second bearing (1000).

[0063] The first bearing (700) may be arranged radially inwardly of the first housing (110). The first bearing (700) may be arranged radially inwardly of an upper region of the first housing (110). The first bearing (700) may be coupled to a bearing holder (800) coupled to a central region of the bearing housing of the first housing (110). The first bearing (700) may rotatably couple the rotation shaft (200) to the first housing (110).

[0064] The inner ring (710) of the first bearing (700) can be coupled to the outer surface of the rotation shaft (200). The outer ring (720) of the first bearing (700) can be supported by the first housing (110) via the bearing holder (800). The outer ring (720) of the first bearing (700) can be supported by the bearing holder (800). The outer surface of the outer ring (720) of the first bearing (700) is supported by the inner surface of the bearing holder (800), and the lower surface of the outer ring (720) of the first bearing (700) can be in contact with the upper surface of the first horizontal portion (810) of the bearing holder (800).

[0065] The bearing holder (800) can be positioned between the first bearing (700) and the first housing (110) in a direction perpendicular to the axial direction, horizontally, or radially.

[0066] The bearing holder (800) may include a first horizontal portion (810) that supports the lower surface of the outer ring (720) of the first bearing (700), a first vertical portion (820) that extends axially upwardly from a radially outer region of the first horizontal portion (810) and contacts the outer surface of the outer ring (720) of the first bearing (700), a second horizontal portion (830) that extends radially outwardly from an axially upper region of the first vertical portion (820), and a second vertical portion (840) that extends axially downwardly from a radially outer region of the second horizontal portion (830).

[0067] An elastic member (900) may be placed between the lower surface of the second horizontal portion (830) and the upper surface of the first support portion (114) extending radially inward from the lower surface of the inner surface (112) of the first housing (110). The outer surface of the second vertical portion (840) may face the inner surface (112) of the first housing (110).

[0068] The outer surface of the second vertical portion (840) may include a groove (842) that is concavely formed radially inward. A support damper (850) may be arranged in the groove (842) of the second vertical portion (840). The support damper (850) may be formed of an elastic material. The support damper (850) may extend in the circumferential direction. The support damper (850) may be referred to as an 'O-ring'. The support damper (850) may be arranged between the second vertical portion (840) and the inner surface (112) of the first housing (110). The support damper (850) may absorb vibration between the housing and the rotational shaft to prevent resonance and reduce noise generation.

[0069] The elastic member (900) may be arranged axially between the bearing holder (800) and the first housing (110). The elastic member (900) may be formed of an elastic material. The elastic member (900) may be a coil spring. The elastic member (900) may extend circumferentially. The upper surface of the elastic member (900) may be supported by the lower surface of the second horizontal portion (830) of the bearing holder (800), and the lower surface of the elastic member (900) may be supported by the upper surface of the first support portion (114) of the first housing (110). In other words, the upper surface of the elastic member (900) may be in contact with the lower surface of the second horizontal portion (830), and the lower surface of the elastic member (900) may be in contact with the upper surface of the first support portion (114).

[0070] By forming an outward preload on both sides of the first bearing (700) and the second bearing (1000) through the bearing holder (800) and the elastic member (900), the vertical movement of the first bearing (700), the rotation shaft (200), and the second bearing (1000) can be enabled. Through this, an accurate gap between the inner surface of the second housing (120) and the blades of the impeller (500) can be set, and a constant gap between the inner surface of the second housing (120) and the blades of the impeller (500) can be maintained even when the motor (20) is operated at high speed, thereby ensuring reliability. In addition, since the gap between the inner surface of the second housing (120) and the impeller (500) can be set, interference between the inner surface of the second housing (120) and the blades of the impeller (500) can be prevented.

[0071] Since the elastic member (900) extends in the circumferential direction, the first bearing (700) and the rotation shaft (200) are positioned radially centered with respect to the first housing (110). That is, while maintaining the balance of the rotor (300), the alignment between the first bearing (700) and the second bearing (1000) is maintained due to the balancing effect of the elastic member (900), thereby increasing the durability life of the bearings (700, 1000).

[0072] The second bearing (1000) may be coupled to the central region of the diffuser (600). Here, the central region of the diffuser (600) may mean a region that overlaps the second bearing (100) in the axial or radial direction with respect to the rotational axis (200). The rotational axis (200) may be rotatably coupled to the second bearing (1000). The second bearing (1000) may rotatably couple the rotational axis (200) to the diffuser (600).

[0073] The inner ring (1010) of the second bearing (1000) may be coupled to the outer circumferential surface of the rotation shaft (200). The upper surface of the outer ring (1020) of the second bearing (1000) may be supported by the diffuser (600). Specifically, the outer circumferential surface of the outer ring (1020) of the second bearing (1000) may be coupled to the inner circumferential surface (602) of the diffuser (600), and the upper surface of the outer ring (1020) of the second bearing (1000) may be in contact with the lower surface of the second support portion (604) that extends radially inward from an upper region of the inner circumferential surface (602) of the diffuser (600).

[0074] At least a portion of the rotor (300), at least a portion of the impeller (500), and at least a portion of the diffuser (600) may be arranged between the first bearing (700) and the second bearing (1000) in the axial direction. This allows the impeller (500) to have a support structure at both ends positioned between the two bearings (700, 1000), thereby reducing noise generated when the rotor (300) rotates.

[0075] Although the embodiments of this specification have been described with reference to the attached drawings, those skilled in the art will appreciate that the present invention can be implemented in other specific forms without altering the technical concept or essential features thereof. Therefore, the embodiments described above should be understood to be illustrative in all respects and not restrictive.

Claims

1. Housing; A first bearing arranged radially inside the housing; A rotary shaft rotatably coupled to the first bearing; A rotor coupled to the above rotational axis and positioned below the first bearing; A stator assembly disposed radially outside the rotor; An impeller coupled to the above rotating shaft and positioned below the rotor; A diffuser coupled to the housing and positioned below the impeller; A second bearing coupled to the central region of the diffuser and rotatably coupled to the rotation axis; and A bearing holder is disposed radially between the first bearing and the housing, At least a portion of the lower surface of the first bearing is supported by the bearing holder, A motor wherein at least a portion of the upper surface of the second bearing is supported by the diffuser.

2. In paragraph 1, The above impeller is a motor located downstream of the flow path generated by the rotation of the above impeller.

3. In paragraph 1, A motor further comprising an elastic member disposed axially between the bearing holder and the housing.

4. In paragraph 3, The inner ring of the first bearing is coupled to the rotation shaft, A motor in which the lower surface of the outer ring of the first bearing is supported by the bearing holder.

5. In paragraph 4, A motor in which the bearing holder includes a first horizontal portion supporting a lower surface of an outer ring of the first bearing, a first vertical portion extending axially upwardly from a radially outer region of the first horizontal portion and contacting an outer surface of the outer ring of the first bearing, a second horizontal portion extending radially outwardly from an upper region of the first vertical portion, and a second vertical portion extending axially downwardly from a radially outer region of the second horizontal portion.

6. In paragraph 5, The housing includes a first support portion extending radially inwardly from a lower region of the inner surface facing the first bearing, and a step portion formed between the first support portion and the inner surface, A motor in which the upper surface of the elastic member contacts the lower surface of the second horizontal portion, and the lower surface of the elastic member contacts the upper surface of the first support portion.

7. In paragraph 1, A motor in which the inner ring of the second bearing is coupled to the rotation shaft, and the upper surface of the outer ring of the second bearing is supported by the diffuser.

8. In paragraph 1, The above diffuser includes a second support extending radially inwardly from an upper region of the inner surface, A motor in which the upper surface of the outer ring of the second bearing is supported by the second support member, and the outer peripheral surface of the outer ring of the second bearing is in contact with the inner peripheral surface of the diffuser.

9. In paragraph 1, The upper region of the above impeller is a motor directly facing the above stator assembly.

10. In paragraph 1, It comprises a first housing and a second housing that surrounds the impeller and is coupled to the first housing, The first bearing is arranged radially inwardly on the inner surface of the upper region of the first housing, The above diffuser is a motor disposed in the lower area of ​​the second housing.

11. Housing; A first bearing arranged radially inside the housing; A rotary shaft rotatably coupled to the first bearing; A rotor coupled to the above rotational axis and positioned below the first bearing; A stator assembly disposed radially outside the rotor; An impeller coupled to the above rotating shaft and positioned below the rotor; A diffuser coupled to the above housing; A second bearing coupled to the central region of the diffuser and rotatably coupled to the rotation axis; and A bearing holder is disposed radially between the first bearing and the housing, A motor wherein at least a portion of the rotor, at least a portion of the impeller, and at least a portion of the diffuser are disposed between the first bearing and the second bearing.

12. In paragraph 11, The above impeller is a motor located downstream of the flow path generated by the rotation of the above impeller.

13. In paragraph 11, A motor further comprising an elastic member disposed axially between the bearing holder and the housing.

14. In paragraph 13, The inner ring of the first bearing is coupled to the rotation shaft, A motor in which the lower surface of the outer ring of the first bearing is supported by the bearing holder.

15. In paragraph 14, A motor in which the bearing holder includes a first horizontal portion supporting a lower surface of an outer ring of the first bearing, a first vertical portion extending axially upwardly from a radially outer region of the first horizontal portion and contacting an outer surface of the outer ring of the first bearing, a second horizontal portion extending radially outwardly from an upper region of the first vertical portion, and a second vertical portion extending axially downwardly from a radially outer region of the second horizontal portion.

16. In paragraph 15, The housing includes a first support portion extending radially inwardly from a lower region of the inner surface facing the first bearing, and a step portion formed between the first support portion and the inner surface, A motor in which the upper surface of the elastic member contacts the lower surface of the second horizontal portion, and the lower surface of the elastic member contacts the upper surface of the first support portion.

17. In paragraph 11, A motor in which the inner ring of the second bearing is coupled to the rotation shaft, and the upper surface of the outer ring of the second bearing is supported by the diffuser.

18. In paragraph 11, The above diffuser includes a second support extending radially inwardly from an upper region of the inner surface, A motor in which the upper surface of the outer ring of the second bearing is supported by the second support member, and the outer peripheral surface of the outer ring of the second bearing is in contact with the inner peripheral surface of the diffuser.

19. In paragraph 11, The upper region of the above impeller is a motor directly facing the above stator assembly.

20. In paragraph 11, The housing comprises a first housing and a second housing surrounding the impeller and coupled to the first housing, The first bearing is arranged radially inwardly on the inner surface of the upper region of the first housing, The above diffuser is a motor disposed in the lower area of ​​the second housing.

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