KR20240059284A - Fan motor - Google Patents

Abstract

The fan motor starts. The fan motor includes a rotating shaft, a transmission unit, a plurality of bearings, a plurality of bearing housings, and a heat dissipation fin. An impeller is mounted on the rotating shaft. The electric unit includes a rotor connected to the rotating shaft and a stator surrounding the rotor to drive the rotating shaft. The plurality of bearings support the rotation shaft. The plurality of bearing housings accommodate the bearings. The heat dissipation fin is formed of a material different from that of the bearing housing, and is provided between the bearing housing and the bearing to surround the bearing. An uneven portion is formed between the bearing housing and the heat dissipation fin. According to this, the uneven portion can improve adhesion between different materials.

Description

Fan motor {FAN MOTOR}

The present invention relates to a fan motor, and more specifically to a fan motor that can improve the reliability of bearings.

Electric motors can be installed in home appliances such as vacuum cleaners or hair dryers.

Vacuum cleaners, header dryers, etc. can generate rotational force by using an electric motor as a power source.

For example, an electric motor may be coupled with a fan. A fan can generate airflow by receiving power from an electric motor and rotating it.

A handheld vacuum cleaner or hair dryer is operated by lifting it with the user's hand.

In order to increase user portability and convenience, vacuum cleaners, hair dryers, etc. need to be miniaturized and lightweight.

In order to reduce the weight of the vacuum cleaner fan motor, it is desirable to use plastic instead of metal as the housing material.

However, in the case of plastic materials, the heat transfer coefficient (thermal conductivity) is lowered from 1/10 to 1/35 compared to existing metal materials, so the plastic housing surrounding the bearing hinders the bearing's heat dissipation.

As a result, the temperature of the bearing housing made of plastic rises by more than 25°C compared to the bearing housing made of metal, which shortens the lifespan of the bearing and reduces the reliability of the fan motor.

In order to solve the above-mentioned problem, a heat sink made of a material with high thermal conductivity while having a shape that surrounds the bearing and is exposed to the air is needed.

When injecting a bearing housing made of plastic, the bearing housing and heat sink can be insert-molded as one piece so that the heat sink of different materials such as metal is located within the bearing housing.

However, heat sinks and bearing housings made of different materials are manufactured through an injection process, making it impossible to apply adhesive between the inner peripheral surface of the bearing housing and the outer peripheral surface of the heat sink or to add additional adhesive material during the process.

Additionally, due to differences in thermal expansion coefficients between the different materials, a phenomenon in which parts of the bearing housing and the heat sink are separated or separated from each other occurs.

As a result, the concentricity between the bearings supporting the rotating shaft may be misaligned or the assembly with other parts may be incorrect, resulting in a problem that adversely affects the reliability of the fan motor.

Prior patent document US 9,897,104 B2 (2018.02.20.; hereinafter referred to as patent document 1) includes a heat sink assembly to reduce the temperature of the bearing.

The heat sink assembly includes a sleeve, a first heat sink, and a second heat sink. The sleeve is formed in a cylindrical shape and surrounds the bearing. The first heat sink is fixed to one end of the sleeve. The second heat sink is fixed to the other end of the sleeve.

The second heat sink includes a hub provided in the center and a plurality of legs extending radially outward from the hub.

However, the heat sink assembly of Patent Document 1 is composed of the parts of the sleeve, the first heat sink, and the second heat sink, but these parts are manufactured separately from each other, so there is no problem of adhesion between different materials due to double injection. .

Additionally, according to Patent Document 1, an impeller and a rotor core are mounted on both ends of the rotating shaft. A plurality of bearings are disposed between the impeller and the rotor core. A plurality of bearings support the rotating shaft.

Since it is a one-sided bearing support structure in which a plurality of bearings are placed on one side of a relatively heavy rotor core, there are limitations in stably supporting the rotating shaft.

Prior patent document US 2022/0094237 A1 (2022.3.24.; hereinafter referred to as patent document 2) discloses an electric motor having a heat dissipation structure of a bearing.

The can surrounds the bearing housing and acts as a heat dissipation fin.

Heat from the ball bearings generated during motor operation is discharged to the outside of the motor through the ball bearing housing, can, motor casing, and casing cover.

However, according to Patent Document 2, although the can simply surrounds the bearing housing, problems with adhesion between the can and the bearing housing may still occur. In addition, there is no structure to expand the contact area between the can and the bearing, so there is a limit to improving heat dissipation performance.

Additionally, the bearing of Patent Document 2 supports the rotating shaft. There is one bearing and it is mounted on one side of the rotating shaft. One bearing is placed on one side of the rotor core.

In this case, one bearing has limitations in stably and rotatably supporting the relatively heavy rotor core (or permanent magnet). In particular, it is difficult to expect stable support of the bearing when the fan motor rotates at high speed or as the fan motor becomes smaller and lighter.

The purpose of the present invention is to provide a fan motor with a structure that can solve the above-mentioned problems.

The first purpose is to provide a fan motor with a heat dissipation fin in a structure that can improve the adhesion between different materials during insert injection so that the metal heat dissipation fin is located inside the plastic bearing housing.

The second purpose is to provide a fan motor with heat dissipation fins structured to increase the contact area with the plastic bearing housing.

The third purpose is to provide a fan motor with heat dissipation fins in a structure that can reduce the temperature of the bearing by expanding the area exposed to the air.

The fourth purpose is to provide a fan motor with heat dissipation fins structured to increase bearing capacity.

The fifth purpose is to provide a fan motor with a structure that can significantly contribute to reducing the weight of the motor by using a housing made of plastic.

The sixth purpose is to provide a fan motor with a structure that not only secures the insulation distance between the metal heat dissipation fin and the coil, but also reduces the axial length of the fan motor.

As a result of the inventor's intensive research, the problems of the present invention and the above-mentioned first to sixth objectives can be achieved by the following embodiments of the present invention.

(One) In order to achieve the first object described above, a fan motor according to an embodiment of the present invention includes a rotating shaft on which an impeller is mounted; An electric unit including a rotor connected to the rotating shaft and a stator surrounding the rotor, and driving the rotating shaft; a plurality of bearings supporting the rotating shaft; a plurality of bearing housings accommodating the bearings; and a heat dissipation fin formed of a material different from that of the bearing housing, provided between the bearing housing and the bearing and surrounding the bearing, and an uneven portion is formed between the bearing housing and the heat dissipation fin.

(2) In (1), the concave-convex portion according to one embodiment includes a protrusion formed to protrude from the outer peripheral surface of the heat dissipation fin toward the inner peripheral surface of the bearing housing; And it may include a protrusion receiving groove that is concavely formed on the inner peripheral surface of the bearing housing and accommodates the protrusion.

(3) In (1), the concavo-convex portion according to another embodiment includes a protrusion formed to protrude from the inner peripheral surface of the bearing housing toward the outer peripheral surface of the heat dissipation fin; And it may include a protrusion receiving groove that is concavely formed on the outer peripheral surface of the heat dissipation fin and accommodates the protrusion.

(4) In (1), the concavo-convex portion according to another embodiment includes a first protrusion formed to protrude from the outer peripheral surface of the heat dissipation fin toward the inner peripheral surface of the bearing housing; a second protrusion formed to protrude from the inner peripheral surface of the bearing housing toward the outer peripheral surface of the heat dissipation fin; a first protrusion receiving groove formed concavely on an inner peripheral surface of the bearing housing and accommodating the first protrusion; and a second protrusion receiving groove that is concavely formed on the outer peripheral surface of the heat dissipating fin and accommodates the second protrusion, wherein the first protrusion and the second protrusion receiving groove are disposed adjacent to each other along the axial direction on the outer peripheral surface of the heat dissipating fin. The second protrusion and the first protrusion receiving groove may be arranged adjacent to each other along the axial direction on the inner peripheral surface of the bearing housing.

(5) In (1), the heat dissipation fin may be formed in a cylindrical shape.

(6) In (2) or (3), the concavo-convex portion is formed to extend along a spiral direction, and the protrusion and the protrusion receiving groove may be engaged with each other.

(7) In (2) or (3), the protrusion and the protrusion receiving groove may be formed to be inclined downward from one axial end of the heat dissipation fin or the bearing housing toward the other axial end along the circumferential direction.

(8) In (1), a protrusion may be formed radially inward from the inner peripheral surface of the heat dissipation fin, and an elastic member may be provided between the bearing and the protrusion to press the bearing in the axial direction.

(9) In (2) or (3), the protrusions and the protrusion-receiving grooves are arranged to face each other in the radial direction to form a pair, and are provided in a plurality of pairs, and the plurality of protrusions and the plurality of protrusion-receiving grooves are provided in pairs. may be arranged to be spaced apart in the circumferential direction.

(10) In (2) or (3), the protrusion and the protrusion receiving groove are formed to correspond to each other and may have a polygonal or circular cross-sectional shape.

(11) In (1), the heat dissipation expansion rib may further be formed to protrude outward in the radial direction from the outer peripheral surface of the heat dissipation fin.

(12) In (1), the bearing housing may be made of a plastic material, and the heat dissipation fin may be made of a metal material.

(13) In (1), the plurality of bearings include a first bearing and a second bearing respectively mounted on both sides of the rotating shaft with the rolling unit interposed therebetween, and the plurality of bearing housings include the first bearing. A first bearing housing that accommodates; and a second bearing housing for accommodating the second bearing, wherein the heat dissipation fin includes: a first heat dissipation fin surrounding the first bearing and disposed inside the first bearing housing; It surrounds the second bearing and includes a second heat dissipation fin disposed inside the second bearing housing.

(14) In (13), a stopper is disposed to face the impeller and extends radially inward from one end of the first bearing housing to cover the first bearing.

(15) In (1), the stator includes a coil, and an insulating cover may be further provided between the coil and the heat dissipation fin to cover the heat dissipation fin.

In (1) above, a shroud accommodating the impeller; a plurality of vanes coupled to the inside of the shroud and guiding the flow of air sucked by the impeller; and a vane hub having the plurality of vanes on an outer peripheral surface, wherein the first bearing is disposed on a downstream side of the impeller based on the air flow direction, and the first bearing housing is located on the inside of the vane hub. It can be accepted.

According to embodiments of the present invention, the following effects can be achieved.

First, a heat dissipation fin is provided between the bearing and the bearing housing made of plastic. The heat dissipation fin may be formed in a cylindrical shape to surround the bearing. The heat dissipation fin is made of a metal material and radiates heat received from the bearing into the air during operation of the fan motor.

The bearing housing surrounds the heat dissipation fin, and an uneven portion is provided between the heat dissipation fin and the bearing housing. The uneven portion includes projections and projection receiving grooves.

The protrusion may be formed to protrude from the heat dissipation fin, and the protrusion receiving groove may be formed to be recessed in the bearing housing. The protrusion and the protrusion receiving groove are arranged to overlap each other in the radial direction, and the protrusion is accommodated in the protrusion receiving groove. The protrusions and the protrusion-receiving grooves are male and female and can be in surface contact.

Alternatively, conversely, the protrusion-receiving groove may be formed on the heat radiation fin, and the protrusion may be formed on the bearing housing.

Alternatively, the first projection and the second projection receiving groove may be alternately disposed along the axial direction on the heat radiation fin, and the first projection receiving groove and the second projection may be alternately disposed along the axial direction on the bearing housing. The first protrusion is received in the first protrusion receiving groove, and the second protrusion is received in the second protrusion receiving groove.

The protrusion and the protrusion receiving groove may extend along the spiral direction of the heat radiation fin or bearing housing. Each of the protrusions and protrusion receiving grooves may extend inclined downward from one axial end of the heat dissipation fin toward the other axial end.

Here, one axial end of the heat radiation fin may be disposed adjacent to one axial end (open side) of the bearing housing, and the other axial end of the heat radiation fin may be disposed adjacent to a protrusion formed on the other axial end of the bearing housing.

The protrusion may be formed to protrude radially outward from the outer peripheral surface of the heat dissipation fin or may be formed to protrude radially inward from the inner peripheral surface of the bearing housing.

The protrusion receiving groove may be formed to be recessed radially inward from the outer peripheral surface of the heat radiation fin or may be formed to be recessed radially outward from the inner peripheral surface of the bearing housing.

The protrusion and protrusion receiving groove increase the contact area between the heat dissipation fin and the bearing housing. Additionally, the spiral shape of the protrusion and protrusion receiving groove gives directionality in the axial direction in which the heat dissipation fin is fastened to the bearing housing. In particular, when the protrusion of the heat dissipation fin rotates along the protrusion receiving groove of the bearing housing, the heat dissipation fin can be moved in the axial direction toward the inside of the bearing housing.

Here, giving direction means allowing the protrusion to move in the axial direction in which the heat dissipation fin is fastened to the inside of the bearing housing along the protrusion receiving groove, but in the axial direction in which the protrusion is released toward the outside of the bearing housing along the protrusion receiving groove. This means that movement is not allowed.

In the case of insert injection molding so that the metal heat radiation fin is located inside the plastic bearing housing to manufacture the bearing housing and the heat radiation fin as one piece, it is impossible to inject adhesive between the bearing housing and the heat radiation fin.

For this reason, when the rotational force of the rotating shaft is transmitted to the heat radiation fin through the bearing during high-speed rotation of the rotation shaft, the heat radiation fin may move in the axial direction while rotating along the inner peripheral surface of the bearing housing.

However, the spiral structure of the protrusion and the protrusion receiving groove according to the present invention allows the heat dissipation fin to move to the inside of the bearing housing, but does not allow the heat dissipation fin to move to the outside of the bearing housing.

Accordingly, the bonding force between the bearing housing and the heat dissipation fin is improved.

Second, as the contact area between the bearing housing and the heat dissipation fin increases, the heat dissipation area increases, thereby improving heat dissipation performance.

Third, at the other axial end of the heat dissipation fin, a plurality of heat dissipation expansion ribs protrude outward in the radial direction and are exposed to the air, thereby further improving the cooling performance of the bearing by increasing the air exposed area of the heat dissipation fin.

Fourth, the protrusion and protrusion receiving groove increase the bonding force between the heat radiation fin and the bearing housing, thereby minimizing axial misalignment between the two bearings.

Fifth, the structure in which the protrusion of the heat dissipation fin and the protrusion receiving groove of the bearing housing are combined can improve the adhesion between the bearing housing and the heat dissipation fin without adding additional parts or adding adhesive.

Sixth, the structure of combining the protrusions of the heat radiation fin and the protrusion-receiving grooves of the bearing housing can eliminate additional assembly processes and enable mass production through insert injection molding, thereby reducing manufacturing costs.

1 is a perspective view showing the appearance of a fan motor according to the present invention.
FIG. 2 is an exploded view showing the fan motor of FIG. 1 disassembled.
FIG. 3 is a plan view showing the fan motor in FIG. 1 as seen from above.
FIG. 4 is a cross-sectional view showing a cross section of the fan motor taken along line IV-IV in FIG. 3.
Figure 5 is a perspective view showing the structure of the heat dissipation fin in Figure 3.
Figure 6 is a side view showing the heat dissipation fin in Figure 5 as seen in the radial direction.
Figure 7 is a plan view showing the heat dissipation fin of Figure 5 as seen from above.
FIG. 8 is a cross-sectional view showing a cross section of the heat dissipation fin taken along line VIII-VIII in FIG. 7.
Figure 9 is a bottom view showing the heat dissipation fin of Figure 5 as seen from below.
FIG. 10 is an enlarged view of X in FIG. 4 showing the wave washer applying a preload to the bearing.
Figure 11 is a conceptual diagram showing a heat dissipation fin according to another embodiment of the present invention mounted on a bearing housing.

Hereinafter, a fan motor according to an embodiment of the present invention will be described in detail with reference to the attached drawings.

In the following description, in order to clarify the characteristics of the present invention, descriptions of some components may be omitted.

One. Definition of Terms

Terms containing ordinal numbers, such as first, second, etc., may be used to describe various components, but the components are not limited by the terms. The above terms are used only for the purpose of distinguishing one component from another.

When a component is said to be "connected" or "connected" to another component, it is understood that it may be directly connected to or connected to the other component, but that other components may exist in between. It should be. On the other hand, when it is mentioned that a component is “directly connected” or “directly connected” to another component, it should be understood that there are no other components in between.

As used herein, singular expressions include plural expressions unless the context clearly dictates otherwise.

The “fan motor” used in the following description can be understood as a concept meaning a device that sucks or blows air by rotating a fan using power such as an electric motor.

As used in the following description, “radial” or “radial” means a shape that extends like the spokes of a wheel in all directions from a central point.

“Thrust” used in the following description means that when an impeller sucks a fluid such as air in the axial direction, the fluid exerts the same force on the impeller in the direction opposite to the axial direction, and acts on the impeller or the rotating shaft on which the impeller is mounted. It means the power to

“Axial direction” used in the following description means the longitudinal direction of the rotation axis.

The “radial direction” used in the following description refers to the longitudinal direction of a line segment extending from the center of a circle or cylinder to a point on the circumference of the circle.

“Circumferential direction” used in the following description means the direction of the circumference of a circle.

The terms “upper”, “lower”, “right”, “left”, “anterior side” and “posterior side” used in the following description will be understood through the coordinate system shown in FIG. 1.

The “axial direction” used in the following description can be understood as a concept corresponding to the vertical direction.

The “radial direction” used in the following description may be understood as a concept corresponding to the left-right direction or front-to-back direction.

2. Description of the configuration of a fan motor according to an embodiment of the present invention

1 is a perspective view showing the appearance of a fan motor according to the present invention.

FIG. 2 is an exploded view showing the fan motor of FIG. 1 disassembled.

FIG. 3 is a plan view showing the fan motor in FIG. 1 as seen from above.

FIG. 4 is a cross-sectional view showing a cross section of the fan motor taken along line IV-IV in FIG. 3.

FIG. 5 is a perspective view showing the structure of the heat dissipation fin 160 in FIG. 3.

FIG. 6 is a side view showing the heat dissipation fin 160 in FIG. 5 as viewed in the radial direction.

FIG. 7 is a plan view showing the heat dissipation fin 160 of FIG. 5 as seen from above.

FIG. 8 is a cross-sectional view showing a cross-section of the heat dissipation fin 160 taken along line VIII-VIII in FIG. 7.

Figure 9 is a bottom view showing the heat dissipation fin 160 of Figure 5 as seen from below.

FIG. 10 is an enlarged view showing the wave washer 166 applying a preload to the bearing 151 by enlarging X in FIG. 4.

The fan motor of the present invention can be applied to home appliances such as handy stick vacuum cleaners.

The fan motor may be largely composed of a casing, an impeller 138, and a transmission unit.

The casing forms the exterior of the fan motor. The casing includes a shroud 100, a first housing 110, and a second housing 120. The casing may be formed of a plastic material.

The shroud 100 has an accommodating space therein to accommodate the impeller 138 and the vane 139. The shroud 100 forms the exterior of the fan motor. The air movement passage created by the impeller 138 may be formed between the shroud 100 and the impeller 138, and between the shroud 100 and the vane hub 140, which will be described later.

The shroud 100 may be formed in a cylindrical shape. However, the shroud 100 may be formed to have a different diameter along the longitudinal direction of the cylinder.

Looking at the detailed configuration of the shroud 100, the shroud 100 includes an intake port 101, a curved portion 102, 103, an inclined portion 104, a straight portion 105, a radius expansion portion 106, and a coupling portion. It may be configured to include a unit 107. The detailed configuration of the shroud 100 may be divided in the order from the upstream side to the downstream side of the shroud 100 based on the air flow direction.

The intake port 101 is located at the upstream end of the shroud 100. The intake port 101 is formed in a cylindrical shape. The intake port 101 has a relatively small diameter and short length compared to other detailed configurations of the shroud 100. The intake port 101 may be formed to penetrate in the axial direction. One end of the impeller 138 may be accommodated inside the suction port 101.

Through this, the air generated by the impeller 138 is sucked in through the intake port 101.

The inclined portion 104 is provided on the downstream side of the intake port 101. The inclined portion 104 is formed to be inclined with respect to the rotation axis 150 so that its diameter gradually increases from the upstream side to the downstream side of the shroud 100.

The curved portions 102 and 103 may be composed of a first curved portion 102 and a second curved portion 103. The first curved portion 102 is formed in a curved shape with a preset first curvature to connect the suction port 101 and the inclined portion 104. The second curved portion 103 is formed in a curved shape with a preset second curvature to connect the inclined portion 104 and the straight portion 105.

The curved directions of the first curved portion 102 and the second curved portion 103 may be in opposite directions. The first curvature and the second curvature may be different from each other.

The straight portion 105 has a larger diameter than the inclined portion 104. The straight portion 105 is formed in a cylindrical shape. A plurality of vanes 139, which will be described later, may be coupled to the inner peripheral surface of the straight portion 105 to enable contact.

The radius expansion portion 106 is formed to extend in the radial direction between the straight portion 105 and the coupling portion 107. The radius expansion portion 106 is formed to extend along the circumferential direction of the straight portion.

The rotation axis 150 is provided at the center of the casing. The rotation axis 150 is formed to extend along an axial direction passing through the center of the casing.

One end of the rotation shaft 150 is accommodated inside the shroud 100. An impeller 138 is rotatably mounted on one end of the rotation shaft 150.

The impeller 138 includes a hub 1381 and a plurality of blades 1382.

The hub 1381 is formed to be inclined so that its diameter increases along the axial direction. The diameter of the hub 1381 gradually increases from the upstream end to the downstream end of the hub 1381 based on the direction of air movement.

An axial through hole is formed inside the hub 1381 to penetrate in the axial direction so that one end of the rotating shaft 150 penetrates the center of the hub 1381 and is coupled thereto.

Each of the plurality of blades 1382 may be formed to extend spirally along the axial direction of the hub 1381. One end of the blade 1382 may be formed to protrude in the radial direction from the axial end of the hub 1381. The other end of the blade 1382 may be formed to protrude in the axial direction from the other axial end of the hub 1381.

The plurality of blades 1382 are arranged to be spaced apart at a predetermined interval along the circumferential direction of the hub 1381.

According to this, the impeller 138 can rotate together with the rotation shaft 150. A plurality of blades 1382 rotating at high speed together with the hub 1381 can suck in external air by flowing air in the inner space of the shroud 100.

The vane 139 is provided on the outer peripheral surface of the vane hub 140.

The vane hub 140 may be formed in a cylindrical shape. The diameter of the vane hub 140 may be larger than the maximum diameter of the hub 1381. The length of the vane hub 140 may be shorter than the diameter of the vane hub 140.

There may be a plurality of vanes 139. A plurality of vanes 139 are arranged to be spaced apart in the circumferential direction along the outer peripheral surface of the vane hub 140. The plurality of vanes 139 are formed to protrude outward in the radial direction from the outer peripheral surface of the vane hub 140. The plurality of vanes 139 may have a preset curvature and be formed to be inclined in a curved shape.

The bending (tilting) direction of the vane 139 may be formed in a direction opposite to the bending (tilting) direction of the blade 1382. For example, based on the air flow direction, the blade 1382 may be formed to be inclined in a clockwise direction, and the vane 139 may be formed to be inclined in a counterclockwise direction.

Vanes 139 are configured to change the flow direction of air from the radial direction to the axial direction. Through this, the air generated by the impeller 138 can be guided by the vanes 139 and flow in the axial direction.

A bearing through-hole may be formed in the center of the vane hub 140 so that the first bearing housing 152a, which will be described later, is inserted and coupled. The center of the vane hub 140 surrounds the first bearing housing 152a inserted through the bearing through hole.

The first recess 141 may be formed to be recessed on one axial surface of the vane hub 140. The first recess 141 is formed to surround the edge and lower surface of the vane cover 143.

The vane cover 143 may be inserted into and coupled to the first recess 141 to cover the upper surface of the vane hub 140. The height of the edge of the vane cover 143 may be formed to correspond to the axial depression depth of the vane hub 140.

According to this, since the upper surface of the edge of the vane cover 143 and the upper surface of the vane hub 140 are located on the same plane, the air sucked through the inlet 101 flows when moving from the impeller 138 to the vane 139. Resistance can be minimized.

A second recess 144 may be formed to be recessed on one axial surface of the vane cover 143. The outer end of the hub 1381 is received in the second recess 144. The second recess 144 is formed to surround the edge and lower surface of the hub 1381 at a preset distance from the hub 1381 in the axial and radial directions.

Based on the bottom of the second recess 144, the height of the outer end of the hub 1381 and the height of the upper surface of the edge of the vane cover 143 are located on the same plane, so the air sucked through the intake port 101 is directed to the impeller ( When moving from 138) to the vane 139, flow resistance can be minimized.

A stopper receiving hole 145 may be formed in the center of the vane cover 143 so that a stopper 1521, which will be described later, can be inserted. The center of the vane cover 143 is configured to surround the stopper 1521 inserted through the stopper receiving hole 145.

A plurality of fastening holes 142 and 146 may be formed to penetrate the vane cover 143 and the vane hub 140 in the axial direction, respectively. The plurality of first fastening holes 142 formed in the vane cover 143 and the plurality of second fastening holes 146 formed in the vane cover 143 are arranged to overlap in the axial direction. The plurality of first and second fastening holes 142 and 146 are arranged to be spaced apart in the circumferential direction.

The first fastening member 147, such as a screw, passes through the first fastening hole 142 and the second fastening hole 146 and is fastened to the vane cover 143 and the vane hub 140. Through this, the vane cover 143 and the vane hub 140 can be coupled to each other.

A receiving groove 149 may be formed to accommodate the screw head portion of the first fastening member 147 on the lower surface of the vane cover 143.

The outer diameter of the plurality of vanes 139 protruding in the radial direction from the outer peripheral surface of the vane hub 140 may be formed to correspond to the inner diameter of the straight portion 105 of the shroud 100. According to this, the outer ends of the plurality of vanes 139 can be press-fitted to the inner peripheral surface of the straight portion 105 of the shroud 100.

In addition, the vane hub 140 is fixed to the shroud 100 by a plurality of vanes 139, surrounds the first bearing housing 152a and is coupled to the first bearing housing 152a, forming the first bearing housing (152a). 152a) can be supported.

The rotation shaft 150 is provided inside the shroud 100 to be rotatable with respect to the shroud 100.

The bearing 151 is configured to rotatably support the rotating shaft 150. There may be a plurality of bearings 151.

The bearing 151 may be composed of a first bearing 151a and a second bearing 151b.

The first bearing 151a and the second bearing 151b are arranged to be spaced apart from each other on both sides of the rotation shaft 150 with a transmission unit, which will be described later, interposed therebetween.

A first bearing support portion is provided on one side of the rotation shaft 150. A second bearing support part is provided on the other side of the rotation shaft 150.

An impeller support portion is formed at one end of the rotating shaft 150. The first bearing support portion may be formed to have the same diameter as the impeller support portion.

A rotor support part is provided on the rotation shaft 150. A rotor support part may be formed to extend in the axial direction between the first bearing support part and the second bearing support part.

The diameters of the first bearing support portion and the second bearing support portion are formed to be smaller than the diameter of the rotor support portion.

The first step formed between the first bearing support and the rotor support may restrict the first bearing 151a from moving in the axial direction toward the rotor 135.

The second step formed between the second bearing support portion and the rotor support portion may restrict the second bearing 151b from moving in the axial direction toward the rotor 135.

The following description of the bearing 151 may be applied to the first bearing 151a and the second bearing 151b, respectively, unless otherwise specified.

Bearing 151 may be implemented as a ball bearing. The ball bearing is made to support the radial load of the rotating shaft 150. The bearing 151 may be composed of an outer ring 1511, an inner ring 1512, a plurality of balls 1513, and a plurality of covers 1514 (see FIG. 10).

The outer ring 1511 is formed in a cylindrical shape. The bearing housing 152 may be formed to surround the outer ring 1511. The inner ring 1512 is formed in a cylindrical shape. The inner ring 1512 is provided inside the outer ring 1511 to surround the bearing support.

A plurality of balls 1513 are disposed between the outer ring 1511 and the inner ring 1512. The plurality of balls 1513 are arranged to be spaced apart from each other at a predetermined distance in the circumferential direction of the outer ring 1511 and the inner ring 1512.

A plurality of balls 1513 are in rolling contact between the outer ring 1511 and the inner ring 1512. The inner ring 1512 rotates relative to the outer ring 1511 by the balls 1513. The inner ring 1512 rotates together with the rotation shaft 150.

A plurality of covers 1514 are combined to cover both axial sides of the outer ring 1511 and the inner ring 1512, respectively.

According to this, the plurality of bearings 151 can stably and rotatably support both sides of the rotation shaft 150.

The bearing housing 152 is formed in a cylindrical shape. A bearing receiving hole is formed to penetrate in the axial direction at the center of the bearing housing 152. The bearing housing 152 accommodates the bearing 151 through a bearing receiving hole.

The first bearing housing (152a) accommodates and surrounds the first bearing (151a). The second bearing housing (152b) accommodates and surrounds the second bearing (151b).

The first housing 110 is inserted and fixed inside the shroud 100.

The first housing 110 is disposed on the downstream side of the vane 139 based on the moving direction of air.

The first housing 110 includes a first bearing housing 152a, a plurality of first bridges 113, and a first coupling ring 111.

The first bearing housing (152a) is provided inside the first coupling ring (111). The first coupling ring 111 is formed in a ring shape. The outer diameter of the first coupling ring 111 is formed to correspond to the inner diameter of the coupling portion 107 of the shroud 100.

The first coupling ring 111 may be press-fitted to the inner peripheral surface of the coupling portion 107 of the shroud 100. The first coupling ring 111 is fixed to the inner peripheral surface of the shroud 100.

The inner diameter of the first coupling ring 111 is larger than the diameter of the first bearing housing (152a). The first bearing housing (152a) is disposed inside the first coupling ring (111).

The plurality of first bridges 113 extend in the radial direction between the inner peripheral surface of the first coupling ring 111 and the outer peripheral surface of the first bearing housing 152a. The outer end of the first bridge 113 is connected to the first coupling ring 111, and the inner end of the first bridge 113 is connected to the first bearing housing (152a).

A flow guide 112 is provided on the inner peripheral surface of the first coupling ring 111. The flow guide 112 is configured to guide the flow direction of the air passing through the vane 139 to the inside of the transmission unit.

The flow guide 112 has a preset curvature and is formed in a curved shape.

The flow guide 112 is formed to protrude in the radial direction from the inner peripheral surface of the first coupling ring 111.

The axial end of the flow guide 112 is made to contact the radius expansion portion 106. The inner diameter of one axial end of the flow guide 112 may be formed to correspond to the inner diameter of the straight portion 105.

The other axial end of the flow guide 112 is made to contact the axial end of the second housing 120, which will be described later. The inner diameter of the other axial end of the flow guide 112 may be formed to correspond to the inner diameter of the axial end of the second housing 120 .

Based on the inner peripheral surface of the coupling portion 107, the inner diameter of the radius expansion portion 106 may be formed to be larger than the inner diameter of one axial end of the second housing 120.

The radial protrusion length of the other axial end of the flow guide 112 may be greater than the radial protrusion length of the axial end of the flow guide 112.

The inner peripheral surface of the flow guide 112 has an arc-shaped cross-sectional shape. The inner diameter of the flow guide 112 may be formed to gradually become smaller from one axial end of the flow guide 112 to the other axial end.

The inner peripheral surface of the flow guide 112 is formed to connect one end of the axial direction of the second housing 120 to the straight portion 105.

According to this, the flow guide 112 can minimize the flow resistance of air passing through the vane 139.

The first bridge 113 is disposed on the downstream side of the vane hub 140 based on the moving direction of air. The first bridge 113 may be coupled to the vane hub 140.

A first fastening groove 114 is formed at the inner end of the first bridge 113. The first fastening groove 114 is arranged to overlap the first fastening hole 142 of the vane cover 143 and the second fastening hole 146 of the vane hub 140 in the axial direction. The first fastening member 147, such as a screw, passes through the first and second fastening holes 142 and 146 and is fastened to the first fastening groove 114.

Through this, the first bridge 113 and the vane hub 140 are coupled to each other.

As the impeller 138 rotates, external air is sucked in from the intake port 101 toward the coupling portion 107 in the first axis direction. At this time, the sucked air exerts a thrust of the same magnitude as the suction force of the impeller 138 on the impeller 138 and the rotation shaft 150 in the second axis direction opposite to the first axis direction.

The first bearing 151a may move in the second axis direction opposite to the air suction direction by the thrust acting on the rotation shaft 150.

To solve this problem, a stopper 1521 is provided at one axial end of the first bearing housing 152a. The stopper 1521 extends radially from the axial end of the first bearing housing 152a to cover the axial end of the first bearing 151a.

An axial through hole is formed in the center of the stopper 1521 to penetrate in the axial direction. The shaft through hole is formed to be slightly larger than the diameter of the rotating shaft 150.

According to this, the stopper 1521 can restrict the first bearing 151a from moving in the second axis direction due to thrust.

The thrust acting on the rotation shaft 150 is transmitted to the first housing 110 through the first bearing 151a, the first bearing housing 152a, the first bridge 113, and the first coupling ring 111.

The first housing 110 may be called a load-side housing in that it is located on one side of the rotation shaft 150 that receives thrust.

The second housing 120 may be called a half-load side housing in that it is located on the opposite side of the load side housing.

The second housing 120 may be inserted and coupled to the inside of the shroud 100.

The second housing 120 is disposed downstream of the first housing 110 based on the direction of air movement.

The second housing 120 includes a second coupling ring 121, a receiving portion 124, a second bearing housing 152b, and a second bridge 125.

The second coupling ring 121 is formed in a circular ring shape. The second coupling ring 121 is disposed to face the first coupling ring 111.

The outer diameter of the second coupling ring 121 is formed to correspond to the inner diameter of the coupling portion 107 of the shroud 100. The second coupling ring 121 may be press-fitted to the inner peripheral surface of the coupling portion 107 of the shroud 100.

The first coupling ring 111 and the second coupling ring 121 may have different radial widths. For example, the radial width of the second coupling ring 121 may be formed to be larger than the radial width of the first coupling ring 111.

The radial width of the second coupling ring 121 may be greater than or equal to the radial width of the other axial end of the flow guide 112. The radial width of the second coupling ring 121 is formed to be constant along the axial direction.

The inner edge of one axial end of the second coupling ring 121 is formed in a curved shape. According to this, the flow resistance of air entering the inside of the second coupling ring 121 from the flow guide 112 can be minimized.

The second coupling ring 121 has a receiving space formed therein to accommodate the stator core 131 of the electric motor, which will be described later.

A protruding rib 115 is provided at the other axial end of the first bridge 113 and protrudes into the inner receiving space of the second coupling ring 121. The protruding rib 115 may be formed to protrude in a direction opposite to the first coupling ring 111. The outer peripheral surface of the protruding rib 115 is formed to enable surface contact with the inner peripheral surface of the second coupling ring 121.

A coupling hole 116 is formed to penetrate in the axial direction at the outer end of the first bridge. The diameter of the coupling hole 116 is smaller than the circumferential width of the first bridge 113.

The coupling hole 116 is disposed between the first coupling ring 111 and the protruding rib 115. The plurality of coupling holes 116 are arranged to be spaced apart at equal intervals along the circumferential direction of the flow guide 112. In this embodiment, the plurality of coupling holes 116 are shown spaced apart at 120 degree intervals.

According to this, the protruding ribs 115 can reinforce the strength of the first bridge 113, which has been reduced due to the coupling hole 116. In addition, the protruding rib 115 protrudes so as to be inserted into the inner peripheral surface of the second coupling ring 121, thereby improving the assembly of the first housing 110 and the second housing 120.

A plurality of second fastening grooves 122 may be formed at one end of the second coupling ring 121 in the axial direction. The second fastening groove 122 is positioned to overlap the coupling hole 116 in the axial direction.

The second fastening member 148, such as a screw, is fastened to the first bridge 113 and the second coupling ring 121 through the coupling hole 116 and the second coupling groove 122. Through this, the first housing 110 and the second housing 120 are fastened to each other by the second fastening member 148.

The second bearing housing 152b is formed in a cylindrical shape. The second bearing housing 152b has a receiving space formed therein to accommodate the second bearing 151b. The second bearing housing 152b is formed to penetrate in the axial direction. The second bearing housing 152b may be formed to surround the second bearing 151b.

The receiving portion 124 is provided on the downstream side of the second coupling ring 121. The receiving portion 124 is configured to accommodate a part of the transmission unit, for example, the coil 132 and the second bearing housing 152b of the stator 130, which will be described later.

The receiving portion 124 is formed in a cylindrical shape. The diameter of the receiving portion 124 is smaller than the diameter of the second coupling ring 121 and larger than the diameter of the second bearing housing (152b).

One axial end of the receiving portion 124 may be connected to the other axial end of the second coupling ring 121.

The radius reduction portion 123 extends in the radial direction between the other axial end of the second coupling ring 121 and one axial end of the receiving portion 124. The radius reduction portion 123 connects the other axial end of the second coupling ring 121 and the axial end of the receiving portion 124.

The second bearing housing 152b is disposed inside the receiving portion 124. The second bearing housing 152b is disposed on the downstream side of the coil 132 of the stator 130 based on the moving direction of air.

The second bridge 125 may extend in the radial direction between the receiving portion 124 and the second bearing housing 152b. The outer end of the second bridge 125 may be connected to the other axial end of the receiving portion 124. The inner end of the second bridge 125 may be connected to the outer peripheral surface of the second bearing housing 152b.

The inner end of the second bridge 125 may be connected to the other axial end of the second bearing housing 152b. The second bridge 125 may be provided in plural numbers. The plurality of second bridges 125 may be arranged to be spaced apart in the circumferential direction of the second bearing housing 152b.

A first discharge hole 126a may be formed between the plurality of second bridges 125 adjacent in the circumferential direction to allow air to escape to the outside. The plurality of first discharge holes 126a and the plurality of second bridges 125 are alternately spaced apart in the circumferential direction.

According to this, the plurality of first discharge holes 126a can discharge air passing through the receiving portion 124 in the axial direction.

A plurality of second discharge holes 126b may be formed to penetrate in the radial direction on the side of the receiving portion 124. The plurality of second discharge holes 126b may be arranged to be spaced apart in the circumferential direction. According to this, air can be discharged from the inside of the receiving portion 124 in the radial direction.

The electric motor receives electrical energy to rotate the rotating shaft 150 and rotates the impeller 138 mounted on one end of the rotating shaft 150.

For this purpose, the transmission unit includes a rotor 135 and a stator 130.

The rotor 135 includes a rotor core 136 and a permanent magnet 137.

The rotor core 136 may be constructed by laminating and combining thin electrical steel plates in the axial direction. The rotor core 136 is formed in a cylindrical shape. An axial through hole is formed in the center of the rotor core 136. The axial through hole is formed to penetrate along the axial direction of the rotor core 136.

The rotor core 136 is mounted on the rotation shaft 150. A rotor support part is provided on the rotation shaft 150. The rotation shaft 150 includes a first bearing support portion and a first bearing support portion. The rotor support is disposed between the first bearing support and the second bearing support. The diameter of the rotor support portion may be larger than the diameters of the first bearing support portion and the second bearing support portion.

The rotor 135 may be disposed between the first bearing 151a and the second bearing 151b.

The permanent magnet 137 may be built inside the rotor core 136 or may be mounted on the outer peripheral surface of the rotor core 136. In this embodiment, the permanent magnet 137 is shown mounted on the outer peripheral surface of the rotor core 136.

The stator 130 includes a stator core 131 and a coil 132.

The stator core 131 may be constructed by laminating and combining thin electrical steel plates in the axial direction. The stator core 131 is formed in a cylindrical shape. A rotor through-hole is formed in the center of the rotor core 136. The rotor through hole is formed to penetrate along the axial direction of the stator core 131.

The rotor through hole is formed to be slightly larger than the diameter of the permanent magnet (137). The permanent magnet 137 can maintain a preset distance (air gap) from the inner peripheral surface of the stator core 131.

The stator core 131 includes a back yoke, a plurality of slots, and a plurality of teeth.

The back yoke is formed in a cylindrical shape.

A plurality of teeth are formed to protrude in the radial direction from the back yoke toward the rotation axis 150. Pole shoes may be formed to protrude in the circumferential direction at the inner ends of the plurality of teeth.

A plurality of slots are formed to penetrate along the axial direction of the stator core 131. A plurality of teeth and a plurality of slots are arranged to be alternately spaced apart from each other in the circumferential direction of the stator core 131. In this embodiment, three teeth and three slots are shown.

The plurality of teeth and the plurality of slots may each be arranged to be spaced apart at intervals of 120 degrees in the circumferential direction.

The plurality of coils 132 are each wound on the stator core 131 through a plurality of slots. In this embodiment, there are three coils 132. A three-phase alternating current may be applied to the three coils 132.

The stator 130 is provided with a plurality of connectors 1311 so that external three-phase AC power is supplied to the coil 132. In this embodiment, three connectors 1311 may be provided, one for each phase.

The connector 1311 is configured to electrically connect an external three-phase AC power source and the coil 132. The connector 1311 extends downward in the axial direction from the stator core 131.

A plurality of lead wires 1321 are protruded and exposed to the outside on the axial lower side of the connector 1311.

A connector receiving hole is formed in the receiving portion 124 to accommodate the connector 1311.

An insulator 133 is provided for electrical insulation between the coil 132 and the stator core 131. The insulator 133 may be made of an insulator.

The insulator 133 is disposed between the coil 132 and the stator core 131 to block current from flowing between the coil 132 and the stator core 131.

The plurality of coils 132 and the plurality of insulators 133 may be arranged to be spaced apart from each other at 120 degrees along the circumferential direction of the stator core 131.

The first bridge 113 is located on the upper side of the transmission unit. The first bridge 113 and the coil 132 (or teeth) may be arranged to not overlap in the axial direction. The first bridge 113 does not obstruct the flow of air guided by the flow guide 112 in the vane 139.

The second bridge 125 is located on the lower side of the transmission unit. The second bridge 125 and the coil 132 (or teeth) may be arranged to overlap in the axial direction.

The first bearing 151a and the second bearing 151b, which respectively support both sides of the rotating shaft 150, are supported by different first and second housings 110 and 120.

The first housing 110 and the second housing 120 are each formed in a cylindrical shape. The first and second housings 120 have the same outermost diameter. The first and second housings 110 and 120 are press-fitted to the inner peripheral surface of the coupling portion 107 of one shroud 100, and may be fastened to each other in the axial direction.

To miniaturize and lighten the fan motor, the bearing housing can be manufactured using plastic materials. For example, the bearing housing 152 may be injection molded using a plastic material.

A heat dissipation fin 160 may be provided between the bearing housing 152 and the bearing 151 to dissipate heat generated in the bearing when the fan motor rotates at high speed.

The heat dissipation fin may include a first heat dissipation fin (160a) and a second heat dissipation fin (160b).

The first heat dissipation fin (160a) is provided between the first bearing housing (152a) and the first bearing (151a) to surround the first bearing (151a).

The second heat dissipation fin (160b) is provided between the second bearing housing (152b) and the second bearing to surround the second bearing.

The description of the heat dissipation fin below may be applied in the same or similar manner to the first heat dissipation fin 160a and the second heat dissipation fin 160b, unless otherwise specified.

The heat dissipation fin 160 may be manufactured using a metal material with a high heat transfer coefficient. The heat dissipation fin 160 may be formed in a cylindrical shape. A bearing receiving hole is formed inside the heat dissipation fin 160 to accommodate the bearing 151. The diameter of the bearing receiving hole may be formed to correspond to that of the bearing 151.

The thickness of the heat dissipation fin 160 is formed between the outer peripheral surface and the inner peripheral surface of the heat dissipation fin 160. The heat dissipation fin 160 is formed to surround the bearing 151.

The heat dissipation fin 160 made of metal may be molded integrally with the bearing housing 152 made of plastic.

For example, the heat dissipation fin 160 may be formed by insert injection together with the bearing housing 152 to be located inside the bearing housing 152.

However, a temperature difference may occur between the heat dissipation fin 160 and the bearing housing 152 due to a difference in heat transfer coefficient.

In order to minimize separation that may occur between the heat dissipation fin 160 and the bearing housing 152, uneven portions may be provided between the bearing housing 152 and the heat dissipation fin 160.

The uneven portion may include a protrusion 161 and a protrusion receiving groove 162.

According to this embodiment, the protrusion 161 may be formed to protrude from the outer peripheral surface of the heat dissipation fin 160 toward the bearing housing 152. The protrusion receiving groove 162 may be formed to be concave inward in the radial direction on the inner peripheral surface of the bearing housing 152. The protrusion 161 and the protrusion receiving groove 162 are arranged to face each other in the radial direction. The protrusion 161 may be received and coupled to the protrusion receiving groove 162.

According to another embodiment, the protrusion may be formed to protrude from the inner peripheral surface of the bearing housing 152 toward the outer peripheral surface of the heat dissipation fin 160. The protrusion receiving groove may be formed to be concave inward in the radial direction from the outer peripheral surface of the heat dissipation fin 160. The protrusion and the protrusion receiving groove 162 are arranged to face each other in the radial direction of the bearing housing. The protrusions can be accommodated in and combined with the protrusion receiving grooves.

According to another embodiment, the heat dissipation fin 160 may be provided with a first protrusion and a second protrusion receiving groove. The bearing housing 152 may be provided with a first protrusion receiving groove and a second protrusion.

The first protrusion may be formed to protrude from the outer peripheral surface of the heat dissipation fin 160 toward the inner peripheral surface of the bearing housing 152. The first protrusion may be provided in plural numbers. The plurality of first protrusions may be arranged to be spaced apart along the axial direction on the outer peripheral surface of the heat dissipation fin 160.

The second protrusion receiving groove may be formed between a plurality of first protrusions adjacent in the axial direction. A plurality of second protrusion receiving grooves may be provided. The plurality of second protrusion receiving grooves may be alternately arranged with the plurality of first protrusions along the axial direction on the outer peripheral surface of the heat dissipation fin 160.

The first protrusion receiving groove may be formed concavely in the protruding direction of the first protrusion on the inner peripheral surface of the bearing housing 152. The first protrusion and the first protrusion receiving groove are arranged to face each other, so that the first protrusion can be received and coupled to the first protrusion receiving groove. The first protrusion receiving groove may be provided in plural numbers. The plurality of first protrusion receiving grooves may be arranged to be spaced apart along the axial direction of the bearing housing 152.

The second protrusion may be formed between a plurality of first protrusion receiving grooves adjacent to each other in the axial direction. The second protrusion may be arranged to face the second protrusion receiving groove in the radial direction. The second protrusion may be received and coupled to the second protrusion receiving groove.

The uneven portion may be formed to extend along the spiral direction.

The protrusion 161 and the protrusion receiving groove 162 may be formed to face each other and extend along the spiral direction. The protrusion 161 and the protrusion receiving groove 162 are formed in shapes corresponding to each other.

The protrusion 161 may be formed in the form of a screw thread. The protrusion receiving groove 162 may be formed in the form of a screw groove. The protrusion 161 and the protrusion receiving groove 162 may be engaged with each other.

The protrusion 161 may be formed to slope downward in a counterclockwise direction from one axial end 1601 of the heat dissipation fin 160 to the other axial end 1602 of the heat dissipation fin 160.

A heat dissipation expansion rib 164, which will be described later, may be formed to protrude outward in the radial direction at the other axial end 1602 of the heat dissipation fin 160. A protrusion 165, which will be described later, may be formed to protrude inward in the radial direction at the other axial end 1602 of the heat dissipation fin 160.

When the fan motor rotates at high speed, the outer ring 1511 of the bearing 151 may rotate relative to the inner ring 1512 of the bearing 151. The heat dissipation fin 160 surrounding the outer ring 1511 may also rotate together with the outer ring 1511.

When the heat dissipation fin 160 rotates counterclockwise with respect to FIG. 6, the heat dissipation fin 160 is locked in the axial direction of the dotted arrow by the spiral direction of the protrusion 161.

Here, locked means that the heat dissipation fin 160 is prevented from being separated from the bearing housing 152 in the axial direction while the heat dissipation fin 160 is accommodated inside the bearing housing 152 and is fastened in the axial direction.

The protrusion 161 may have a cross-sectional shape of any one of triangle, square, trapezoid, and semicircle. However, the cross-sectional shape of the protrusion 161 is not limited to this and may be formed in various shapes.

The protrusion 161 may be configured to include a first inclined portion, a second inclined portion, and a connection portion along the axial cross-section. The first inclined portion may be formed to be inclined downward in the protruding direction of the protrusion 161 with respect to the axial direction. The second inclined portion may be formed to be inclined upward in the protruding direction of the protrusion 161 with respect to the axial direction.

The first inclined portion and the second inclined portion may be formed to be inclined toward each other in an intersecting direction. The connection portion may be disposed between the first inclined portion and the second inclined portion. The connection portion may be formed to connect the first inclined portion and the second inclined portion.

The connection portion may be formed in a straight or curved shape.

According to this configuration, the protrusion 161 and the protrusion receiving groove 162 of the uneven portion are formed on the inner peripheral surface of the bearing housing 152 and the heat dissipation fin 160 when the heat dissipation fin 160 made of metal is injected into the bearing housing 152 made of plastic. The bonding force between the outer circumferential surfaces can be improved.

The protrusion 161 and the protrusion receiving groove 162 can expand the contact area between the inner peripheral surface of the bearing housing 152 and the outer peripheral surface of the heat dissipation fin 160.

A protrusion 165 may be formed on the other axial end 1602 of the heat dissipation fin 160 to protrude inward in the radial direction. The protrusion 165 may be formed to extend along the circumferential direction of the heat dissipation fin 160.

Accordingly, the protrusion 165 can prevent the wave washer 166 from being separated from the inside of the heat dissipation fin 160 in the axial direction.

A wave washer 166 may be provided between the axial end of the bearing 151 and the protrusion 165 of the heat dissipation fin 160.

The wave washer 166 applies preload in the axial direction to the outer ring 1511 of the second bearing 151, so that the balls 1513 of the ball bearing move radially or axially between the outer ring 1511 and the inner ring 1512. Shaking can be minimized.

Referring to FIG. 10, while the wave washer 166 presses the outer ring 1511 of the second bearing in the axial direction, the outer ring 1511 moves in the first axial direction toward the insulating cover 153, and the inner ring (1512) and the rotation axis may move in the second axis direction opposite to the first axis direction of the pressing force applied to the outer ring (1511).

The lower portion of the ball-receiving groove of the outer ring 1511 may be in contact with the ball 1513, and the upper portion of the ball-receiving groove of the inner ring 1512 may be in contact with the ball 1513. The inner ring 1512 may be arranged to be spaced apart from the insulating cover 153 with a gap in the axial direction.

In addition to the wave washer 166, an elastic member such as a leaf spring may be used as a means to apply a preload to the bearing 151.

The heat dissipation fin 160 may perform a heat dissipation function to radiate heat generated from the rotation shaft 150 and the bearing 151 to the outside when the fan motor rotates at high speed.

The heat dissipation fin 160 further includes a plurality of heat dissipation expansion ribs 164.

The heat dissipation expansion rib 164 may extend radially outward from the outer peripheral surface of the heat dissipation fin 160. The heat dissipation expansion rib 164 is formed in a plate shape.

The heat dissipation expansion rib 164 may be formed in a rectangular shape with a length longer than the width. The second bridge 125 may be formed in a rectangular plate shape.

The length of the heat dissipation expansion rib 164 may be formed to correspond to the length of the second bridge 125 or may be formed to be smaller than the length of the second bridge 125. In this embodiment, the length of the heat dissipation expansion rib 164 is shown to be smaller than the length of the second bridge 125.

The heat dissipation expansion rib 164 may be supported by the heat dissipation fin 160. One axial surface of the heat dissipation expansion rib 164 may be coupled to the upper surface of the second bridge 125 in a stacked manner.

The plurality of heat dissipation expansion ribs 164 may be arranged to be spaced apart in the circumferential direction. The plurality of heat dissipation expansion ribs 164 may be arranged to overlap the coil 132 in the axial direction.

The heat dissipation expansion rib 164 may be arranged to be spaced apart from the coil 132 at a preset distance in the axial direction. In this embodiment, the heat dissipation expansion ribs 164 are provided in three pieces, and are shown spaced apart at 120 degrees in the circumferential direction.

According to this, the heat dissipation expansion rib 164 expands the contact area with air, so that heat transferred from the heat dissipation fin 160 can be released into the air flowing inside the receiving portion 124.

The heat dissipation expansion rib 164 extends from the upper surface of the second bridge 125 and is connected to the second housing 120 through the second bridge 125, thereby increasing the support strength of the heat dissipation fin 160. .

In addition, the heat dissipation expansion rib 164 is disposed to overlap the coil 132 and does not interfere with the axial flow of air flowing in the space between the plurality of coils 132, thereby providing a space between the plurality of second bridges 125. The flow resistance of air discharged through the first discharge hole 126a can be minimized.

The first heat dissipation fin (160a) and the second heat dissipation fin (160b) may be arranged to face opposite directions.

For example, one axial end of the first heat dissipation fin 160a is disposed toward the coil of the electric drive unit, and the other axial end of the first heat dissipation fin 160a and the protrusion 165a are positioned at the stopper (152a) of the first bearing housing 152a. 1521). However, the first axial movement limiter 1522 is formed to protrude radially inward at one axial end of the first bearing housing 152a, so that the axial end of the first heat dissipation fin 160a moves axially toward the electric drive unit. Movement can be restricted.

The axial end of the second heat dissipation fin 160b is disposed toward the coil of the electric drive unit, and the other axial end of the second heat dissipation fin 160b and the protrusion 165b are toward the second axial movement limiter 1523, which will be described later. can be placed.

The heat dissipation fin 160 is disposed on the downstream side of the coil 132 based on the air flow direction.

Since the heat dissipation fin 160 is a metal conductor, if the distance between the coil 132 and the heat dissipation fin 160 is close, the current flowing in the coil 132 may flow to the heat dissipation fin 160. In order to prevent the current flowing in the coil 132 from leaking to the heat dissipation fin 160, an insulating distance must be secured between the coil 132 and the heat dissipation fin 160.

However, when the axial distance between the coil 132 and the second bearing 151b is widened to secure the insulation distance between the coil 132 and the heat dissipation fin 160, the length of the rotation axis 150 is extended, and the fan As the axial length of the motor increases, a problem arises in which the fan motor becomes larger.

Therefore, it is necessary to shorten the axial length of the fan motor while securing the insulation distance between the coil 132 and the heat dissipation fin 160.

For this purpose, an insulating cover 153 may be provided between the coil 132 and the heat dissipation fin 160. The insulating cover 153 may be made of plastic material.

The insulating cover 153 is provided to cover one end 1601 of the heat dissipation fin 160 in the axial direction. The insulating cover 153 may extend radially inward from one axial end of the second bearing housing 152b toward the rotation axis 150.

The inner end of the insulating cover 153 may be spaced apart from the rotating shaft 150 at a predetermined distance (air gap).

The insulating cover 153 may be formed to cover the outer peripheral surface of the second bearing housing 152b and one end of the second bearing housing in the axial direction.

A plurality of insulating covers 153 may be provided. The plurality of insulating covers 153 may be arranged to be spaced apart from each other at a predetermined distance in the circumferential direction of the second bearing housing 152b. The insulating cover 153 may be connected to and supported by the receiving portion 124 of the second housing 120.

The distance between the coil 132 and the heat dissipation fin 160 is shorter than the distance between the coil 132 and the heat dissipation expansion rib 164.

The insulating cover 153 is disposed between the coil 132 and the second heat dissipation fin (160b). The insulating cover 153 is formed to cover the thickness of the second heat dissipation fin 160b.

According to this, the insulating cover 153 is disposed between the coil 132 and the second heat dissipation fin (160b), and can block current from flowing between the coil 132 and the second heat dissipation fin (160b).

A second axial movement limiter 1523 may be provided at one axial end of the second bearing housing 152b. The second axial movement limiter 1523 may be formed to protrude radially inward from one axial end of the second bearing housing 152b.

The second axial movement limiter 1523 may be formed to extend along the circumferential direction of the second bearing housing 152b. The second axial movement limiter 1523 may be disposed on an axially opposite side of the second bearing housing 152b with respect to the insulating cover 153.

According to this, the second axial movement limiter 1523 may restrict the second heat dissipation fin 160b from moving in the axial direction inside the second bearing housing 152b.

Hereinafter, the operation and effects of the fan motor according to an embodiment of the present invention will be described.

The operating status of the fan motor is as follows.

When current is applied to the coil 132 of the stator 130, a magnetic field is generated around the coil 132. The coil 132 of the stator 130 and the permanent magnet 137 of the rotor 135 interact electromagnetically, so that the rotor 135 rotates about the rotation axis 150 with respect to the stator 130. The rotation shaft 150 rotates together with the rotor 135 and transmits rotational force to the impeller 138. The impeller 138 rotates by the rotational force transmitted through the rotation shaft 150.

The impeller 138 rotates air and sucks external air into the interior of the shroud 100 through the intake port 101. The sucked air passes through the vane (139). Vanes 139 divert the rotational flow of air in the axial direction.

The air converted to axial flow is guided by the flow guide 112 and moves from the inside of the first coupling ring 111 of the first housing 110 to the transmission unit. The air comes into contact with the stator core 131 and coil 132 of the electric motor, and cools the heat generated from the coil 132.

After cooling the coil 132, the air passes through the electric drive unit and is discharged to the outside through the first discharge hole 126a between the second bridge 125 and the second discharge hole 126b on the side of the receiving part 124. .

The plurality of bearings 151 rotatably supports the rotation shaft 150.

The first bearing 151a and the second bearing 151b can stably support both sides of the rotating shaft 150 with the relatively heavy rotor 135 sandwiched between them.

Therefore, according to the present invention, a heat dissipation fin 160 is provided between the bearing and the bearing housing 152 made of plastic. The heat dissipation fin 160 may be formed in a cylindrical shape to surround the bearing 151. The heat dissipation fin 160 is made of a metal material and radiates heat received from the bearing 151 into the air during operation of the fan motor.

The bearing housing 152 surrounds the heat dissipation fin 160, and an uneven portion is provided between the heat dissipation fin 160 and the bearing housing 152. The uneven portion includes a projection 161 and a projection receiving groove 162.

The protrusion 161 may be formed to protrude from the heat dissipation fin 160, and the protrusion receiving groove 162 may be formed to be recessed in the bearing housing 152. The protrusion 161 and the protrusion receiving groove 162 are arranged to overlap each other in the radial direction, and the protrusion 161 is accommodated in the protrusion receiving groove 162. The protrusion 161 and the protrusion receiving groove 162 are male and female and can be in surface contact.

Alternatively, conversely, the protrusion receiving groove 162 may be formed on the heat dissipation fin 160 and the protrusion 161 may be formed on the bearing housing 152.

Alternatively, the first protrusion and the second protrusion receiving groove may be alternately disposed along the axial direction on the heat radiation fin 160, and the first protrusion receiving groove and the second protrusion may be alternately disposed along the axial direction on the bearing housing 152. there is. The first protrusion is received in the first protrusion receiving groove, and the second protrusion is received in the second protrusion receiving groove.

The protrusion 161 and the protrusion receiving groove 162 may extend along the spiral direction of the heat dissipation fin 160 or the bearing housing 152. Each of the protrusions 161 and the protrusion receiving grooves 162 may extend inclined downward from one axial end 1601 of the heat dissipation fin 160 toward the other axial end.

Here, the axial end 1601 of the heat dissipation fin 160 is disposed adjacent to the axial end (open side) of the bearing housing 152, and the other axial end 1602 of the heat dissipation fin 160 is disposed adjacent to the bearing housing 152. It may be disposed adjacent to the protrusion 165 formed at the other axial end of .

The protrusion 161 may be formed to protrude radially outward from the outer peripheral surface of the heat dissipation fin 160 or may be formed to protrude radially inward from the inner peripheral surface of the bearing housing 152.

The protrusion receiving groove 162 may be formed to be recessed radially inward from the outer peripheral surface of the heat dissipation fin 160 or may be formed to be recessed radially outward from the inner peripheral surface of the bearing housing 152.

The protrusion 161 and the protrusion receiving groove 162 increase the contact area between the heat dissipation fin 160 and the bearing housing 152. In addition, the spiral shape of the protrusion 161 and the protrusion receiving groove 162 gives directionality in the axial direction in which the heat dissipation fin 160 is fastened to the bearing housing 152. In particular, when the protrusion 161 of the heat dissipation fin 160 rotates along the protrusion receiving groove 162 of the bearing housing 152, the heat dissipation fin 160 can be moved in the axial direction toward the inside of the bearing housing 152. You can.

Here, providing direction means allowing the protrusion 161 to move along the protrusion receiving groove 162 in the axial direction where the heat dissipation fin 160 is fastened to the inside of the bearing housing 152, but the protrusion 161 is This means that the heat dissipation fin 160 along the receiving groove 162 is not allowed to move in the unwinding axial direction toward the outside of the bearing housing 152.

In the case of insert injection so that the metal heat radiation fin 160 is located inside the plastic bearing housing 152 in order to manufacture the bearing housing 152 and the heat radiation fin 160 as one piece, the bearing housing 152 and the heat radiation fin 160 are (160) It is impossible to add adhesive between them.

For this reason, when the rotational force of the rotary shaft is transmitted to the heat dissipation fin 160 through the bearing 151 during high-speed rotation of the rotary shaft, the heat dissipation fin 160 may move in the axial direction while rotating along the inner peripheral surface of the bearing housing 152.

However, the spiral structure of the protrusion 161 and the protrusion receiving groove 162 according to the present invention allows the heat dissipation fin 160 to move inside the bearing housing 152, but the heat dissipation fin 160 does not move into the bearing housing 152. Movement outside of is not permitted.

Accordingly, the bonding force between the bearing housing 152 and the heat dissipation fin 160 is improved.

Additionally, as the contact area between the bearing housing 152 and the heat dissipation fin 160 increases, the heat dissipation area increases, thereby improving heat dissipation performance.

In addition, at the other axial end 1602 of the heat dissipation fin 160, a plurality of heat dissipation expansion ribs 164 protrude outward in the radial direction and are exposed to the air, thereby increasing the air exposed area of the heat dissipation fin 160, thereby increasing the bearing 151. ) cooling performance can be further improved.

3. Description of the configuration of a fan motor according to another embodiment of the present invention

Figure 11 is a conceptual diagram showing the heat dissipation fin 160 mounted on the bearing housing 152 according to another embodiment of the present invention.

This embodiment is different from the embodiments of FIGS. 1 to 10 described above in the shape and arrangement of the projections 261 and the projection receiving grooves 262 of the uneven portion.

The protrusion 261 may be formed to protrude radially outward from the outer peripheral surface of the heat dissipation fin 260 toward the inside of the bearing housing 152b. The cross-sectional shape of the protrusion 261 may be formed in various shapes such as square, triangle, or trapezoid. In this embodiment, the protrusion 261 is shown to be formed in a square cross-sectional shape.

The protrusions 261 may be provided in plural numbers. The plurality of protrusions 261 may be arranged to be spaced apart in the circumferential direction. The plurality of protrusions 261 may have the same or different heights along the axial direction of the heat dissipation fin 260. This embodiment shows a plurality of protrusions 261 located at the same height in the axial direction.

The plurality of protrusions 261 may be arranged to be spaced apart in the axial direction.

The protrusion receiving groove 262 is formed to correspond to the protrusion 261. The protrusion 261 is accommodated in the protrusion receiving groove 262. The protrusion receiving groove 262 is formed to surround the protrusion 261.

In the embodiment of FIG. 11, the protrusion 261 is formed on the heat dissipation fin 260, and the protrusion receiving groove 262 is described as a structure formed on the bearing housing 152b. However, the protrusion 261 and the protrusion receiving groove 262 are formed on the bearing housing 152b. It can be formed the other way around.

The edge of the cross section of the protrusion 261 may be formed not in an angular shape but in a curved shape such as an arc shape.

Since other components are the same or similar to the embodiments of FIGS. 1 to 10 described above, duplicate descriptions will be omitted.

100: shroud 101: intake port
102: first curved portion 103: second curved portion
104: inclined portion 105: straight portion
106: radius expansion part 107: coupling part
110: first housing 111: first coupling ring
112: Flow guide 113: First bridge
114: first fastening groove 115; protruding ribs
116: coupling hole 120: second housing
121: second coupling ring 122: second fastening groove
123: Radius reduction part 124: Receiving part
125: 2nd bridge 126a: 1st discharge hole
126b: second discharge hole 130: stator
131: stator core 1311: connector
132: coil 1321: lead wire
133 ; Insulator 135: Rotor
136: rotor core 137: permanent magnet
138: Impeller 1381: Hub
1382: Blade 139: Vane
140: vane hub 141: first recess
142: first fastening hole 143: vane cover
144: second recess 145: stopper receiving hole
146: second fastening hole 147: first fastening member
148: second fastening member 149: receiving groove
150: Rotating shaft 151: Bearing
151a: first bearing 151b: second bearing
1511: outer ring 1512: inner ring
1513: Ball 1514: Cover
152: Bearing housing 1521: Stopper
1522: Second axial movement limiter 152a: First bearing housing
152b: Second bearing housing 153: Insulating cover
160, 260: heat dissipation fin 1601: first
1602: Other end 160a: First heat dissipation fin
160b: Second heat dissipation fin 161, 261: Protrusion
162, 261: Protrusion receiving groove 164, 264: Heat dissipation expansion rib
165, 265: protrusion 166: wave washer

Claims (16)

A rotating shaft on which the impeller is mounted;
An electric unit including a rotor connected to the rotating shaft and a stator surrounding the rotor, and driving the rotating shaft;
a plurality of bearings supporting the rotating shaft;
a plurality of bearing housings accommodating the bearings; and
It is formed of a material different from the material of the bearing housing, and includes a heat dissipation fin provided between the bearing housing and the bearing and surrounding the bearing,
A fan motor in which an uneven portion is formed between the bearing housing and the heat dissipation fin. According to paragraph 1,
The uneven portion,
a protrusion formed to protrude from the outer peripheral surface of the heat dissipation fin toward the inner peripheral surface of the bearing housing; and
A fan motor comprising a protrusion-receiving groove that is concavely formed on an inner peripheral surface of the bearing housing and accommodates the protrusion. According to paragraph 1,
The uneven portion,
a protrusion formed to protrude from the inner peripheral surface of the bearing housing toward the outer peripheral surface of the heat dissipation fin; and
A fan motor that is concavely formed on an outer peripheral surface of the heat dissipation fin and includes a protrusion-receiving groove that accommodates the protrusion. According to paragraph 1,
The uneven portion,
a first protrusion formed to protrude from the outer peripheral surface of the heat dissipation fin toward the inner peripheral surface of the bearing housing;
a second protrusion formed to protrude from the inner peripheral surface of the bearing housing toward the outer peripheral surface of the heat dissipation fin;
a first protrusion receiving groove formed concavely on an inner peripheral surface of the bearing housing and accommodating the first protrusion; and
It is concavely formed on the outer peripheral surface of the heat dissipation fin and includes a second protrusion receiving groove for accommodating the second protrusion,
The first protrusion and the second protrusion receiving groove are disposed adjacent to each other along the axial direction on the outer peripheral surface of the heat dissipation fin,
The fan motor wherein the second protrusion and the first protrusion receiving groove are disposed adjacent to each other along the axial direction on the inner peripheral surface of the bearing housing. According to paragraph 1,
A fan motor in which the heat dissipation fin is formed in a cylindrical shape. According to paragraph 2 or 3,
A fan motor in which the concavo-convex portion is formed to extend along a spiral direction, and the protrusion and the protrusion receiving groove are engaged with each other. According to paragraph 2 or 3,
The fan motor wherein the protrusion and the protrusion receiving groove are formed to be inclined downward from one axial end of the heat dissipation fin or the bearing housing toward the other axial end along a circumferential direction. According to paragraph 1,
A protrusion is formed radially inward on the inner peripheral surface of the heat dissipation fin,
A fan motor in which an elastic member is provided between the bearing and the protrusion to press the bearing in an axial direction. According to paragraph 2 or 3,
The protrusion and the protrusion receiving groove are arranged to face each other in the radial direction to form a pair, and are provided in a plurality of pairs, and the plurality of protrusion and the plurality of protrusion receiving groove are respectively arranged to be spaced apart in the circumferential direction. . According to paragraph 2 or 3,
The fan motor wherein the protrusion and the protrusion receiving groove are formed to correspond to each other and have a polygonal or circular cross-sectional shape. According to paragraph 1,
The fan motor further includes a heat dissipation expansion rib formed to protrude radially outward from the outer peripheral surface of the heat dissipation fin. According to paragraph 1,
A fan motor in which the bearing housing is made of a plastic material, and the heat dissipation fin is made of a metal material. According to paragraph 1,
The plurality of bearings are,
It includes a first bearing and a second bearing respectively mounted on both sides of the rotating shaft with the electric motor in between,
The plurality of bearing housings are,
a first bearing housing accommodating the first bearing; and
Includes a second bearing housing for accommodating the second bearing,
The heat dissipation fin is,
a first heat dissipation fin surrounding the first bearing and disposed inside the first bearing housing; and
A fan motor surrounding the second bearing and including a second heat dissipation fin disposed inside the second bearing housing. According to clause 13,
The fan motor further includes a stopper disposed to face the impeller and extending radially inward from one end of the first bearing housing to cover the first bearing. According to paragraph 1,
The stator includes a coil,
A fan motor further provided with an insulating cover between the coil and the heat dissipation fin to cover the heat dissipation fin. According to clause 13,
A shroud accommodating the impeller;
a plurality of vanes coupled to the inside of the shroud and guiding the flow of air sucked by the impeller; and
It includes a vane hub provided with the plurality of vanes on an outer peripheral surface,
The first bearing is disposed on the downstream side of the impeller based on the air flow direction,
The first bearing housing is a fan motor accommodated inside the vane hub.

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