JP2008215391A - Bearing mechanism, motor, air blowing fan and cooling system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To minimize the height of a bearing mechanism, while lengthening the service life of the bearing mechanism having a sleeve impregnated with lubricating oil. <P>SOLUTION: In this bearing mechanism 13, the sleeve 130 is formed by pressing an inner sleeve 131 in an outer sleeve 132, and an upper end surface 1311 of the inner sleeve 131 is positioned on the lower end surface 1312 side more than an upper end surface 1321 of the outer sleeve 132 in the axis J1 direction. Thus, an annular ring-shaped recessed part 136 is formed of an inside surface of the outer sleeve 132, the upper end surface 1311 of the inner sleeve 131 and a shaft 121. The oil content of the inner sleeve 131 is set lower than the oil content of the outer sleeve 132. The outer sleeve 132 functions as an oil retentive mechanism to the inner sleeve 131, and the service life of the bearing mechanism 13 can be lengthened. A lower part of a seal member 124 is also arrange in the recessed part 136, and the height of a motor is minimized. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a sleeve used for a bearing mechanism of a motor, and a bearing mechanism and a motor. Preferably, the motor is used for a cooling device.

  The life of the motor depends on the bearing, and conventionally, ball bearings are often used in consideration of bearing accuracy and reliability. In ball bearings, the use of balls reduces the axial loss, which is the energy consumed by the bearings. However, the centrifugal force acting on the balls shortens the life at high speeds, and even with static loads, There is a limit to extending the service life due to wear of the contact surface.

  On the other hand, a sintered metal body sleeve in which lubricating oil is impregnated in the motor bearing may be used, and such a sliding bearing can reduce the manufacturing cost of the bearing compared to the ball bearing. In the sliding bearing, since the friction between the shaft and the sleeve is reduced by the lubricating oil, it is important to hold a sufficient amount of the lubricating oil for a long time in order to extend the life. For example, in a bearing unit made of a compacted and sintered metal body disclosed in Patent Document 1, lubricating oil is sucked from the outer part to the inner part by making the inner part denser than the outer part, Thereby, the lifetime improvement of a bearing unit is implement | achieved.

Further, in Patent Document 2, the sleeve is composed of two members, an inner part and an outer part, and the durability of the sleeve is improved by impregnating the inner part and the outer part with lubricating oils having different viscosities. Patent Document 3 proposes a technique for suppressing the movement of lubricating oil due to centrifugal force by providing a coarse layer and a dense layer from an inner layer in a bearing that rotates integrally with a rotor. .
JP 2006-292161 A Japanese Patent Laid-Open No. 8-177861 Japanese Utility Model Publication No. 3-69714

  By the way, in the bearing unit of Patent Document 1, the sleeve is divided into an inner part and an outer part to extend the life. However, with the holder and other peripheral members when the sleeve is actually attached to the base part of the motor. Structural relationships and arrangements are not considered.

  The present invention has been made in view of the above problems, and has as its main object to provide a sleeve having a more preferable structure in relation to peripheral members, while extending the life of a motor bearing mechanism.

  The invention according to claim 1 is a bearing mechanism for use in a motor, wherein the outer sleeve is a cylindrical sintered metal body impregnated with lubricating oil, and the cylindrical sintered metal impregnated with lubricating oil. A sleeve having an oil content lower than that of the outer sleeve and inserted into the outer sleeve and having one end surface positioned inside the outer sleeve, and a shaft inserted into the sleeve And a bottomed cylindrical sleeve holder into which the sleeve is inserted, and the one of the inner sleeves facing the one end surface of the shaft, and is provided on the shaft and extends radially outward from the shaft. A surface facing the end surface includes an annular portion located inside the outer sleeve.

  The invention according to claim 2 is the bearing mechanism according to claim 1, wherein the oil content of the inner sleeve is 20% or more and 30% or less, and the oil content of the outer sleeve is 35% or more and 45% or less. It is.

  Invention of Claim 3 is a bearing mechanism of Claim 1 or 2, Comprising: The said annular part is an annular member attached to the said shaft facing the said one end surface of the said inner sleeve. .

  A fourth aspect of the present invention is the bearing mechanism according to the third aspect, wherein the annular member is a seal member.

  A fifth aspect of the present invention is the bearing mechanism according to any one of the first to fourth aspects, wherein a cylindrical side portion and a bottom portion of the sleeve holder are formed as one member, and the sleeve holder The bottom portion has a recess in which a tip member with which the tip of the shaft abuts is disposed.

  The invention according to claim 6 is the bearing mechanism according to claim 5, wherein the tip member is held by the tip holder in the recess, and the tip member and the tip holder face the sleeve. .

  The invention according to claim 7 is the bearing mechanism according to claim 6, wherein the tip member is a magnet, and the tip holder and the shaft are magnetic bodies.

  The invention according to claim 8 is the bearing mechanism according to any one of claims 1 to 4, wherein the bottom portion of the sleeve holder has a recess in which the tip member with which the tip of the shaft abuts is disposed. The whole of the concave portion is opposed to the inner region of the outer sleeve.

  The invention according to claim 9 is the bearing mechanism according to claim 8, wherein the tip member that is a magnet is held in the recess by a tip holder that is a magnetic body, and the shaft is a magnetic body. is there.

  The invention according to claim 10 is a motor, comprising the bearing mechanism according to any one of claims 1 to 9, an armature, and a stator portion to which the bearing mechanism is fixed, and the armature. And a rotor part that is rotatably supported with respect to the stator part by the bearing mechanism.

  The invention described in claim 11 is a blower fan, and includes the motor described in claim 10 and an impeller attached to the rotor portion of the motor and generating an air flow by rotation.

  Invention of Claim 12 is a cooling device, Comprising: The ventilation fan of Claim 11, the thermal radiation part which receives the flow of the air from the said ventilation fan, and the said thermal radiation part are connected, and it is made into cooling object A cooling unit in contact therewith.

  In the present invention, a long life of the bearing mechanism is realized by holding a large amount of lubricating oil in the outer sleeve, and a space for providing an annular portion in the shaft in the vicinity of the end surface of the inner sleeve can be secured. Can be reduced in height.

  Further, in the invention of claim 5, since the cylindrical side portion and the bottom portion of the sleeve holder are formed as one member, it is possible to reliably prevent the leakage of the lubricating oil. Since the movement of the holder is blocked by the sleeve, the structure of the bearing mechanism can be simplified.

  In the invention of claim 8, the recess faces the inner region of the outer sleeve so that the inflow of the lubricating oil into the recess can be suppressed. In the inventions of claims 7 and 9, the magnetic attractive force by the tip member Thus, the movement of the shaft can be prevented and vibration or noise can be suppressed.

  FIG. 1 is a longitudinal sectional view showing a configuration of a cooling device 1 according to a first embodiment of the present invention. The cooling device 1 is a so-called heat sink fan, and includes a blower fan 2 and a heat sink 3 connected to the lower side of the blower fan 2. In FIG. 1, although the cross section in the surface containing the central axis J1 of the ventilation fan 2 is shown, the part is also illustrated about the part located behind a cut surface.

  The blower fan 2 includes an electric motor 10, an impeller 21 that generates an air flow in the direction of the central axis J <b> 1 by the rotation of the motor 10, and a wind tunnel portion 22 that surrounds the side periphery of the impeller 21. The stator portion of the motor 10 is fixed to the wind tunnel portion 22 via a plurality of ribs 23 extending from the lower end of the wind tunnel portion 22 in a direction perpendicular to the central axis J1. The impeller 21 is fixed to the rotor portion of the motor 10 and blows air in a direction toward the heat sink 3 as the rotor portion rotates.

  The heat sink 3 includes a cooling unit 31 that comes into contact with a heating element 9 such as a CPU to be cooled on the lower surface, a heat radiating unit 32 having a plurality of fins 321 that receives the air flow from the blower fan 2, and the blower fan 2. The connection part 33 for connecting upwards is provided. The wind tunnel portion 22 of the blower fan 2 is connected and fixed to the heat sink 3 above the heat radiating portion 32 by the connection portion 33, but the details of the connection mechanism are omitted. Each fin 321 is a flat plate protruding from the cooling unit 31 toward the blower fan 2, and is formed integrally with the cooling unit 31. In the heat sink 3, heat is conducted from the heat generating element 9 to the heat radiating part 32 through the cooling part 31, and the heat radiating part 32 radiates heat by the cooling air sent from the blower fan 2, thereby cooling the heat generating element 9. .

  The shape of the heat sink 3 is not limited to that shown in FIG. 1. For example, the heat sink 3 may be a heat sink provided with a plurality of heat conductor rods protruding from the cooling unit 31 toward the blower fan 2. Moreover, as long as the cooling part and the heat radiating part are thermally connected, they are not necessarily connected integrally as shown in FIG. 1, and may be provided as individual members.

  FIG. 2 is a longitudinal sectional view of the motor 10. As shown in FIG. 2, the motor 10 includes a stator unit 11 that is a fixed assembly, a rotor unit 12 that is a rotating assembly, and a rotor unit 12 that can rotate about the central axis J <b> 1 with respect to the stator unit 11. The bearing mechanism 13 to support is provided. In the following description, for convenience, the rotor part 12 side is described as the upper side and the stator part 11 side is the lower side along the central axis J1, but the direction of the central axis J1 does not necessarily coincide with the direction of gravity.

  The rotor portion 12 is attached to the shaft 121, the rotor hub 122 attached to the upper end portion of the shaft 121, the field magnet 123 attached to the inner surface of the rotor hub 122, and the shaft 121 below the rotor hub 122. An annular seal member 124 is provided. As will be described later, the shaft 121 and the seal member 124 may be regarded as a part of the bearing mechanism 13.

  The rotor hub 122 has a substantially cylindrical shape centering on the central axis J1 in the vicinity of the central axis J1, and a mounting portion 1221 protruding downward, and a substantially circular plate extending perpendicularly to the central axis J1 from the upper end of the mounting portion 1221. And a substantially cylindrical cylindrical portion 1223 extending downward at the outer edge of the circular disc portion 1222, which are one member. The shaft 121 is inserted and fixed to the attachment portion 1221, and the field magnet 123 is fixed to the inner surface of the cylindrical portion 1223.

  The stator portion 11 to which the bearing mechanism 13 is fixed includes a base portion 111, a bottomed cylindrical sleeve holder 112 formed in the center of the base portion 111, and an armature 113 fixed to the outer surface of the sleeve holder 112. Prepare. The field magnet 123 generates a torque around the central axis J1 with the armature 113, whereby the rotor unit 12 rotates. The cylindrical side portion 1121 and the bottom portion 1122 of the sleeve holder 112 are formed as one member, and the base portion 111 and the sleeve holder 112 are also formed as one member. Further, the bottom portion 1122 of the sleeve holder 112 is provided with a recess 1123 in which a later-described chip member 133 is disposed. The sleeve holder 112 may be regarded as a part of the bearing mechanism 13.

  The armature 113 includes a stator core 1131 fixed around the sleeve holder 112, an insulator 1132 that insulates the periphery of the stator core, and a coil 1133 wound around the insulator 1132. The insulator 1132 includes an annular retaining portion 1134 that extends toward the central axis J1 at the upper end. The portion on the central axis J1 side of the retaining portion 1134 and the outer edge portion of the seal member 124 positioned below face each other in the vertical direction, so that the shaft 121 is prevented from being pulled upward.

  FIG. 3 is a view showing the bearing mechanism 13. The bearing mechanism 13 includes a sleeve 130 into which the shaft 121 is inserted, a tip member 133 that magnetically attracts the lower end portion of the shaft 121, and a tip holder 134 that holds the tip member 133. The chip member 133 which is a magnet has a thin plate-shaped thrust plate 1332 disposed on the upper surface of a disk-shaped magnet chip 1331. The shaft 121, the seal member 124, and the sleeve holder 112 into which the sleeve 130 is inserted also serve as a part of the bearing mechanism. The sleeve 130 receives a radial load of the shaft 121, and the tip member 133 receives a thrust load from the shaft 121.

  The sleeve 130 is obtained by inserting (press-fitting) a cylindrical inner sleeve 131 into a cylindrical outer sleeve 132. The inner sleeve 131 and the outer sleeve 132 are sintered metal bodies impregnated with lubricating oil.

  The upper end surface 1311 of the inner sleeve 131 is located below the upper end surface 1321 of the outer sleeve 132 with respect to the central axis J1 direction, that is, on the lower end surface 1312 side of the inner sleeve 131. Therefore, the upper end surface 1311 of the inner sleeve 131 is located inside the outer sleeve 132. As a result, an annular recess 136 is formed by the inner surface of the outer sleeve 132, the upper end surface 1311 of the inner sleeve 131 and the shaft 121. A lower portion of the seal member 124 that faces the inner sleeve 131 in the vertical direction is disposed in the recess 136.

  The sleeve 130 is fixed in the sleeve holder 112 by press-fitting or bonding, and the position of the lower end surface 1312 of the inner sleeve 131 is the same as the lower end surface 1322 of the outer sleeve 132 in the direction of the central axis J1, and the lower end surface 1312 and the lower end surface 1322 are. Is so-called. On the other hand, the diameter of the concave portion 1123 of the bottom 1122 of the sleeve holder 112 is smaller than the inner diameter of the outer sleeve 132, and the entire concave portion 1123 faces the inner region of the outer sleeve 132. In other words, the recess 1123 faces only the inner sleeve 131 with respect to the sleeve 130.

  The chip holder 134 has a dish shape that covers the bottom and outer periphery of the chip member 133 and holds the chip member 133, and is fixed in the recess 1123 by press-fitting. Further, the tip holder 134 is formed of a magnetic body, and by holding the tip member 133 inside to form a magnetic circuit, the lower end portion of the shaft 121 that is a magnetic body is attracted downward with a strong force, and the tip It contacts the member 133 (more precisely, the thrust plate 1332 on the magnet chip 1331). As a result, movement of the shaft 121 in the direction of the central axis J1 is prevented and noise and / or vibration is suppressed. The thrust plate 1332 is fixed to the upper surface of the magnet chip 1331 with an adhesive and is formed of PEEK (polyether ether ketone) resin having excellent wear resistance. Thereby, the friction between the thrust plate 1332 and the shaft 121 is reduced, and the shaft 121 rotates smoothly.

  In the combination of the tip member 133 and the tip holder 134 in the recess 1123, the outer edge directly faces the lower end surface 1312 of the inner sleeve 131 without any inclusions that lock the upward movement. As described above, the bearing mechanism 13 has a simplified structure in which the upward movement of the tip member 133 and the tip holder 134 is directly blocked by the inner sleeve 131.

  Since the lower end surface 1241 of the seal member 124 attached to the shaft 121 is opposed to the upper end surface 1311 of the inner sleeve 131 and the lower end surface 1241 is located inside the outer sleeve 132, it has been transmitted from the sleeve 130 to the shaft 121. The lubricating oil scatters from the lower end surface 1241 to the upper end surface 1311 of the inner sleeve 131 and the inner side surface of the outer sleeve 132 by the centrifugal force generated by the rotation of the shaft 121 and is returned into the sleeve 130. Thereby, leakage of the lubricating oil from the shaft 121 is prevented.

  As described above, the inner sleeve 131 and the outer sleeve 132 are porous sintered metal bodies, and the density of the inner sleeve 131 is higher than that of the outer sleeve 132. Specifically, the oil content of the inner sleeve 131 is 20% or more and 30% or less, and the oil content of the outer sleeve 132 is 35% or more and 45% or less. More preferably, the oil content of the inner sleeve 131 is 22% or more and 28% or less, and the oil content of the outer sleeve 132 is 37% or more and 43% or less. Here, the oil content is a ratio of the volume of the impregnated lubricating oil to the volume of the sleeve 130, and is equal to the porosity of the sintered metal body. By making the oil content of the sleeve 130 higher than that of a general one (both the inner sleeve 131 and the outer sleeve 132), reliability equivalent to that of a ball bearing can be realized.

  When the motor 10 is driven, the shaft 121 is supported by the inner sleeve 131 so as to be smoothly rotatable via the lubricating oil. At this time, the lubricating oil impregnated in the inner sleeve 131 by capillary action is automatically supplied to the contact surface according to the consumption of the lubricating oil on the contact surface between the shaft 121 and the inner sleeve 131, and the performance of the bearing mechanism 13 is maintained. . Then, the lubricating oil is supplied from the outer sleeve 132 having a high oil content to the inner sleeve 131 having a low oil content by capillary action. As described above, the outer sleeve 132 serves as an oil retaining mechanism for the inner sleeve 131, whereby the lubricating oil retaining period of the bearing mechanism 13 can be extended, and the life of the bearing mechanism 13 can be extended.

  Further, the oil content of the inner sleeve 131 is lower than that of the outer sleeve 132, and the recess 1123 is entirely opposed to the inner region of the outer sleeve 132 (in addition, the outer sleeve 132 contacts the inner bottom surface of the sleeve holder 112. Therefore, the lubricating oil is prevented from moving directly from the outer sleeve 132 to the concave portion 1123, and the inflow of the lubricating oil into the concave portion 1123 is suppressed. In particular, even when the chip holder 134 is formed of a sintered material, a large amount of lubricating oil is prevented from flowing out from the outer sleeve 132.

  As described above, in the bearing mechanism 13, a long life is realized by holding a lot of lubricating oil in the outer sleeve 132, and the upper end surface 1311 of the inner sleeve 131 is positioned in the outer sleeve 132. Thus, a recess 136 for attaching the seal member 124 to the shaft 121 can be secured in the vicinity of the upper end surface 1311, and the height of the bearing mechanism 13 can be reduced. Further, by adopting the sleeve 130 which is a sliding bearing in the bearing mechanism 13, the price of the motor 10 and the blower fan 2 can be reduced as compared with the case where a ball bearing is used.

  By providing the recess 136 in the sleeve 130, it is possible to easily grasp the top and bottom of the sleeve 130 during assembly, and to prevent the sleeve 130 from being inserted into the sleeve holder 112 in a state where the top and bottom are reversed.

  Further, in the bearing mechanism 13, the cylindrical side portion 1121 and the bottom portion 1122 of the sleeve holder 112 are formed as one member, so that leakage of the lubricating oil can be reliably prevented and the center of the chip holder 134 can be prevented. Since the movement in the direction of the axis J1 is blocked by the sleeve 130, the structure of the bearing mechanism 13 is simplified.

  FIG. 4 is a view showing another example of the bearing mechanism. In the bearing mechanism 13a shown in FIG. 4, the upper end portion 1341 of the outer edge of the chip holder 134 abuts on the lower end surface 1312 of the inner sleeve 131, and the other configuration is the same as that of the bearing mechanism 13 shown in FIG. In the bearing mechanism 13a, since the position of the chip holder 134 is completely restrained by the lower end surface 1312 and the recess 1123, the movement of the chip holder 134 in the direction of the central axis J1 is completely prevented. Therefore, the chip holder 134 does not necessarily need to be press-fitted into the recess 1123.

  FIG. 5 is a view showing still another example of the bearing mechanism. In the bearing mechanism 13 b shown in FIG. 5, the lower end surface 1312 of the inner sleeve 131 is positioned below the lower end surface 1322 of the outer sleeve 132 and is positioned in the recess 1123. The upper end portion 1341 of the outer edge of the chip holder 134 is opposed to the lower end surface 1312 of the inner sleeve 131 with contact or a gap. The other structure is the same as that of the bearing mechanism 13 shown in FIG. Also in the bearing mechanism 13b, the movement of the chip holder 134 is limited by the inner sleeve 131, and the structure of the bearing mechanism 13b can be simplified, and the gap between the recess 1123 and the inner sleeve 131 is reduced, so that the recess 1123 The inflow of lubricating oil into the inside can be further suppressed.

  As mentioned above, although embodiment of this invention has been described, this invention is not limited to the said embodiment, A various change is possible.

  For example, the sleeve holder 112 may be formed in a bottomed cylindrical shape by combining a plurality of members as long as the leakage of the lubricating oil can be prevented with high reliability. A stopper (corresponding to the seal member 124 in the above embodiment) attached to the shaft 121 may be provided below the sleeve 130. The sleeve holder 112 may be a separate member from the base portion 111.

  In the above-described embodiment, the seal member 124 is attached to the shaft 121 as one annular member. However, the annular member attached to the shaft 121 may be a member that serves as a retaining member. It may have both functions. Further, instead of being an independent annular member, an annular portion that extends radially outward may be provided integrally with the attachment portion 1221 at the lower end of the attachment portion 1221 into which the shaft 121 is inserted. Further, such an annular portion may be provided integrally with the shaft 121. That is, the annular portion that extends radially outward from the shaft 121 may be provided on the shaft 121 in various manners so as to face the upper end surface 1311 of the inner sleeve 131, and the surface that faces the upper end surface 1311 of the annular portion. By positioning the inside of the outer sleeve 132, it is possible to reduce the height of the bearing mechanism 13.

  In the motor 10 according to the above embodiment, the position of the rotor unit 12 in the direction of the central axis J1 is fixed by the suction of the shaft 121 by the tip member 133. The rotor portion 12 may be drawn downward by being positioned above the target center. The motor 10 may be an inner rotor type in which field magnets are arranged inside the armature.

  The blower fan 2 according to the above-described embodiment is not limited to a use as a cooling device having a heat sink, but may be used for various uses such as other cooling devices and ventilation. Further, the air blowing by the blower fan is not limited to the axial direction, and a bearing mechanism 13 having a sleeve 130 in a so-called centrifugal fan or turbo fan may be used. Furthermore, the motor 10 may be used not only as a driving source for the blower fan but also as various other types of driving sources.

It is a longitudinal cross-sectional view of a cooling device. It is sectional drawing of a motor. It is sectional drawing of a bearing mechanism. It is sectional drawing of another bearing mechanism. It is sectional drawing of another bearing mechanism.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Cooling device 2 Blower fan 10 Motor 11 Stator part 12 Rotor part 13 Bearing mechanism 21 Impeller 31 Cooling part 32 Heat radiation part 112 Sleeve holder 113 Armature 121 Shaft 123 Field magnet 124 Seal member 130 Sleeve 131 Inner sleeve 132 Outer sleeve 133 Tip member 134 Tip holder 1121 (Sleeve holder) side 1122 (Sleeve holder) bottom 1123 Recess 1311 (Inner sleeve) upper end surface 1241 (Seal member) lower end surface

Claims (12)

A bearing mechanism used for a motor,
An outer sleeve that is a cylindrical sintered metal body impregnated with lubricating oil, and a cylindrical sintered metal body that is impregnated with lubricating oil, and the oil content is lower than that of the outer sleeve. A sleeve provided with an inner sleeve that is inserted and has one end face located inside the outer sleeve;
A shaft inserted into the sleeve;
A bottomed cylindrical sleeve holder into which the sleeve is inserted;
An annular portion that is provided on the shaft so as to face the one end surface of the inner sleeve, extends radially outward from the shaft, and a surface facing the one end surface is located inside the outer sleeve;
A bearing mechanism comprising: The bearing mechanism according to claim 1,
The bearing mechanism is characterized in that an oil content of the inner sleeve is 20% or more and 30% or less, and an oil content of the outer sleeve is 35% or more and 45% or less. The bearing mechanism according to claim 1 or 2,
The bearing mechanism, wherein the annular portion is an annular member attached to the shaft so as to face the one end surface of the inner sleeve. The bearing mechanism according to claim 3,
A bearing mechanism in which the annular member is a seal member. The bearing mechanism according to any one of claims 1 to 4,
A cylindrical side portion and a bottom portion of the sleeve holder are formed as one member, and the bottom portion of the sleeve holder has a recess in which a tip member with which the tip of the shaft abuts is disposed. Bearing mechanism. The bearing mechanism according to claim 5,
A bearing mechanism characterized in that the tip member is held by a tip holder in the recess, and the tip member and the tip holder face the sleeve. The bearing mechanism according to claim 6,
The bearing mechanism, wherein the tip member is a magnet, and the tip holder and the shaft are magnetic bodies. The bearing mechanism according to any one of claims 1 to 4,
The bottom of the sleeve holder has a recess in which a tip member with which the tip of the shaft abuts is disposed;
The bearing mechanism characterized in that the whole of the concave portion is opposed to an inner region of the outer sleeve. The bearing mechanism according to claim 8, wherein
In the recess, the tip member that is a magnet is held by a tip holder that is a magnetic body,
A bearing mechanism in which the shaft is made of a magnetic material. A motor,
A bearing mechanism according to any one of claims 1 to 9,
A stator portion having an armature, to which the bearing mechanism is fixed;
A rotor portion having a field magnet for generating torque with the armature, and rotatably supported with respect to the stator portion by the bearing mechanism;
A motor comprising: A blower fan,
A motor according to claim 10;
An impeller attached to the rotor portion of the motor and generating an air flow by rotation;
A blower fan comprising: A cooling device,
A blower fan according to claim 11,
A heat dissipating part that receives a flow of air from the blower fan; and
A cooling unit which is connected to the cooling target and connected to the cooling unit;
A cooling device comprising:

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