JP5321359B2 - Centrifugal fan - Google Patents

Description

  The present invention relates to a centrifugal fan having an impeller.

  In the prior art, for example, Patent Document 1 discloses a centrifugal fan provided with an intake port on a plane perpendicular to the discharge direction of an impeller. However, in mobile devices such as notebook computers, video functions have been strengthened, and as the amount of heat generated by the CPU has increased, not only has a high air flow required for centrifugal fans been required, but there has also been a strong demand for noise reduction. .

JP 2004-92446 A

  However, the conventional centrifugal fan configuration has not proposed a quiet centrifugal fan suitable for video viewing on a mobile device or the like.

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to solve the above-described problems, and to provide a quiet centrifugal fan with low noise even when a sufficient air volume sufficient for cooling is maintained.

In the centrifugal fan of the first aspect of the present invention, the exhaust portion and the casing are formed in the discharge direction of the impeller, the intake portion is formed in a direction perpendicular to the discharge direction of the impeller, and the impeller has a cup shape A centrifugal fan in which a plurality of blades are radially formed on a circumferential portion of the boss, and a shaft is attached to the boss, and a flocked portion is formed on the impeller, and the flocked portion is used as the suction portion of the blade. Formed on the surface of all the non-opposing areas of the blade, and is configured such that no flocking is performed in the area of the blade facing the air intake portion, and the non-opposing area is an outer peripheral side of the blade and parallel to the axis The region is characterized in that the height dimension is maximized .

The centrifugal fan of the invention of claim 2 is characterized in that the hair length of the flocked portion is 2 mm or less.

In the centrifugal fan according to a third aspect of the present invention, the direction of the hair of the flocked portion is a direction substantially perpendicular to the surface of the blade.

According to the invention of claim 1, noise is reduced by flocking the centrifugal fan. There is little decrease in the air volume due to flocking to the centrifugal fan, and noise at the same air volume can be reduced compared to conventional centrifugal fans.

According to invention of Claim 2 , the fall of the airflow by the flocking to a centrifugal fan is few, and the noise in the same airflow can be made small compared with the conventional centrifugal fan.

According to invention of Claim 3 , the effect to the centrifugal fan by flocking is optimized, and noise can be made small.

It is an external appearance perspective view of the centrifugal fan which shows 1st Example of this invention. It is an external appearance perspective view of the centrifugal fan seen from the A direction of FIG. 1 same as the above. It is sectional drawing of a centrifugal fan same as the above. FIG. 3 is an external view of the main part of the centrifugal fan with the cover removed. It is an external view of an impeller same as the above. It is a principal part sectional drawing of a braid | blade same as the above. FIG. 6 is a graph showing the relationship between the air volume and noise of each centrifugal fan in the centrifugal fan of the present invention and the conventional centrifugal fan. Same as above, in the centrifugal fan of the present invention, the conventional centrifugal fan, and the centrifugal fan in which the entire surface of the impeller in the conventional centrifugal fan is flocked, the amount of airflow and noise when each centrifugal fan is mounted on the casing of the device. It is a graph which shows a relationship. It is an external view of the cooling unit containing the centrifugal fan which shows 2nd Example of this invention.

  Hereinafter, preferred embodiments of a centrifugal fan according to the present invention will be described with reference to the accompanying drawings.

  The overall configuration of the centrifugal fan 100 according to the present embodiment will be described with reference to FIGS. 1 to 6. Reference numeral 1 denotes a rotating impeller, and reference numeral 2 denotes a casing having the impeller 1 therein. The impeller 1 includes a blade 3 as a plurality of blades and a cup-shaped boss 4, and a blade 3 as a centrifugal fan 100 main body is provided on a circumferential portion of the boss 4 that forms a central portion of the impeller 1. Radially formed. Further, a motor 5 serving as a driving unit for the impeller 1 is disposed inside the boss 4. The motor 5 includes a stator 6 having an iron core (core) on which windings are mounted, a rotor (yoke) 7 attached to the inner peripheral portion of the boss 4 and rotated by a magnetic force from the stator 6, the stator 6 and other Each element is mounted and configured by a circuit board 8 as a charging unit constituting an electric circuit as the motor 5.

  The casing 2 that forms the outline of the centrifugal fan 100 includes a bottomed case 9 that surrounds the impeller 1 and a cover 10 that covers the upper opening of the case 9, both of which are formed of members having excellent thermal conductivity. Is done. Further, the case 9 is formed with an island-shaped motor mounting wall 12 connected to the periphery thereof by spokes 11. The motor 5 is installed on the motor mounting wall 12, and the motor 5 except for the motor mounting wall 12 side is installed. Almost the entire surface is surrounded by a cup-shaped boss 4. More specifically, a cylindrical bearing 13 is erected substantially at the center of the motor mounting wall 12 which is a motor 5 mounting portion, while a shaft 14 which is a rotating shaft is mounted at the center of the boss 4. The shaft 14 is rotatably supported by the bearing 13.

  The rotor 7 and the impeller 1 around the shaft 14 are rotated by the electromagnetic action of the magnet 15 attached to the inner peripheral surface of the rotor 7 and the stator 6 facing the magnet 15. Reference numeral 16 denotes a lead wire for electrical connection with the stator 6.

  The impeller 1 is rotatably mounted by a bearing 13 and a shaft 14, and a rotor 7 is provided inside the impeller 1, and the rotor 7 has a positional relationship facing the outer periphery of the stator 6. . The rotor 7 rotates with the fan by the rotating magnetic field of the stator 6 so that wind is generated.

  The motor mounting wall 12 forms a part of the case 9, and the case 9 is formed with an exhaust port 17 and a casing 2 in the discharge direction of the impeller 1. Further, the case 9 is formed with a first air inlet 18 in a direction perpendicular to the discharge direction of the impeller 1, and the cover 10 attached to the case 9 is opposed to the first air inlet 18. However, another second air inlet 19 is formed in a direction perpendicular to the discharge direction of the impeller 1. The first air inlet 18 is formed by partially connecting the motor mounting wall 12 of the case 9 and the peripheral portion with the spoke 11. Further, the opening area of each intake port 18 and 19 may be appropriately determined in consideration of the suction amount of each intake port 18 and 19.

  A region 20 (hereinafter referred to as a non-opposing region) excluding a region facing the first intake port 18 and the second intake port 19 in the rotational axis direction of the impeller 1 of each blade 3, that is, the axial direction of the shaft 14, That is, in FIG. 3, the electrostatic flocking ( A flocked portion 21 in which the hair F made of a fiber member such as synthetic fiber is planted is formed by a flocking method such as flocking. As shown in FIG. 6, the length L of the hair F applied to the hair transplantation part 21 is 0.3 to 2 mm, and these hairs F are implanted substantially perpendicularly to the surface of the region 20. .

  Since the motor 5 is arranged almost inside the impeller 1 as described above, the centrifugal fan 100 of the present invention is suitable for mounting in a thin housing desired for mobile devices such as notebook computers. The most suitable shape.

  Next, the operation of the above configuration will be described. The centrifugal fan 100 in this embodiment is mounted in a casing of a mobile device (not shown) in order to cool a heat-generating component mounted on a mobile device such as a notebook personal computer. Then, when electric power is supplied to the stator 6 of the motor 5 and the impeller 1 is rotated in the direction of the arrow by the electromagnetic action of the stator 6 and the magnet 15 attached to the inner peripheral surface of the rotor 7, Warm air existing in the gap 31 between the upper surface of the casing 2 and the lower surface of the casing and the casing 2 is sucked from the intake ports 18 and 19, respectively. The air taken in from the intake ports 18 and 19 circulates around the outside of the impeller 1 and reaches the exhaust port 17, from which the centrifugal fan 100 and thus the outside of the casing are discharged.

  Here, when the collision between the air passing through the impeller 1 and the impeller 1 is alleviated by forming the flocked portion 21 in the impeller 1, the pressure fluctuation of the air passing through the impeller 1 is suppressed, Noise such as wind noise caused by the impeller 1 is reduced.

  Further, by forming the flocked portion 21 in the region 20 of the blade 3, the collision between the air passing through the impeller 1 and the blade 3 of the impeller 1 is alleviated, and the pressure fluctuation of the air passing through the impeller 1 is reduced. In addition to being suppressed and reducing noise, the flocked portion 21 is formed in the region 20 that is a portion of the blade 3 that is not opposed to the intake ports 18 and 19, so that the flocked portion of the blade 3 facing the intake ports 18 and 19 can be implanted. By not performing, since the increase in resistance at the time of intake of the air taken into the casing 2 from the intake ports 18 and 19 is prevented, a decrease in the air volume is suppressed.

  Furthermore, by setting the length L of the hair F of the flocking portion 21 to 0.3 to 2 mm, the pressure fluctuation of the air passing through the impeller 1 is further suppressed and the noise is further reduced. Here, if the length L of the hair F of the flocked portion 21 is less than 0.3 mm, a silent effect cannot be obtained, and if the length L of the hair F of the flocked portion 21 is longer than 2 mm, the wind power is reduced. Therefore, it is not preferable.

  Further, by making the direction of the hair F of the flocked portion 21 to be a direction substantially perpendicular to the surface of the region 20 of the blade 3, the pressure fluctuation of the air passing through the impeller 1 is further suppressed, so that the noise is also increased. It is further reduced.

  FIG. 7 is a graph showing the correlation between the air volume and noise of each centrifugal fan in the centrifugal fan 100 of the present invention and the conventional centrifugal fan, and reference numeral 22 is a characteristic relating to the centrifugal fan 100 of the present invention. Reference numeral 23 denotes characteristics relating to a conventional centrifugal fan. From the figure, it can be seen that the centrifugal fan 100 according to the present invention reduces the generation of noise by about 1 dB.

  FIG. 8 shows the air volume corporal noise in the state where each centrifugal fan is mounted on the casing of the mobile device in the centrifugal fan 100 according to the present invention, the conventional centrifugal fan, and the centrifugal fan in which the entire surface of the impeller 1 is flocked. The reference numeral 24 is a characteristic relating to the centrifugal fan 100 of the present invention, the reference numeral 25 is a characteristic relating to a conventional centrifugal fan, and the reference numeral 26 is a centrifugal where the entire surface of the impeller 1 is flocked. It is the characteristic regarding the fan. From the figure, the centrifugal fan 100 according to the present invention is reduced in noise generation by about 6 dB as compared with the conventional centrifugal fan, and the noise generation is lower than that of the centrifugal fan in which the entire surface of the impeller 1 is flocked. It can be seen that the generation is reduced by about 2 to 3 dB. As can be seen from FIG. 7 and FIG. 8, the centrifugal fan 100 of the present invention can greatly contribute to noise reduction.

  The above embodiment corresponds to claim 1, the exhaust port 17 and the casing 2 are formed in the discharge direction of the impeller 1, and the intake ports 18 and 19 are formed in a direction perpendicular to the discharge direction of the impeller 1. In the centrifugal fan 100, the flocked portion 21 is formed on the impeller 1.

  In this case, since the flocked portion 21 is formed on the impeller 1, the collision between the air passing through the blade 3 of the impeller 1 and the blade 3 of the impeller 1 is alleviated, and the pressure of the air passing through the impeller 1 is reduced. When the fluctuation is suppressed, noise such as wind noise caused by the impeller 1 is reduced.

Further, it corresponds to claim 1 , and the flocked portion 21 is formed in a region 20 that is not opposed to the intake ports 18 and 19 in the blade 3 provided in the impeller 1.

  In this case, the collision between the air passing through the blade 3 of the impeller 1 and the blade 3 of the impeller 1 is mitigated, the pressure fluctuation of the air passing through the impeller 1 is suppressed, noise is reduced, and the flocked portion 21 is The blade 3 is formed in a non-facing region 20 of the blade 3 with respect to the air inlets 18 and 19, and is not implanted into the portion of the blade 3 facing the air inlets 18 and 19. Since the increase in resistance at the time of inhalation of the air taken in is prevented, the decrease in the air volume is suppressed. Thus, there is little fall of the air volume by the flocking to the centrifugal fan 100, and the noise in the same air volume can be made small compared with the conventional centrifugal fan.

Furthermore, it corresponds to claim 2 , and by making the length L of the hair F of the flocked portion 21 2 mm or less, the pressure fluctuation of the air passing through the flocked portion 21 of the impeller 1 is further suppressed, and the noise is further reduced. To do. In this way, there is little decrease in the air volume due to the flocked portion 21 to the centrifugal fan 100, and noise at the same air volume can be reduced as compared with the conventional centrifugal fan.

Further corresponds to claim 3, by which a direction substantially perpendicular to the surface of the region 20 in the direction of the blade 3 of the hair F flocking unit 21, the pressure of the air passing through the bristle portion 21 of the impeller 1 Since the fluctuation is further suppressed, the noise is further reduced. Thus, the effect on the centrifugal fan 100 due to the formation of the flocked portion 21 is optimized, and the noise can be reduced.

  As an effect of the embodiment, in the centrifugal fan 1 of the present embodiment, the air taken into the casing from the intake ports 18 and 19 gradually moves from the inner peripheral side of the blade 3 to the outer peripheral side by the rotation of the impeller 1. And flow. The air reaching the outer peripheral tip of the blade 3 flows along the inner wall of the case, and is then discharged to the outside from the exhaust port 17 arranged in a direction orthogonal to the intake ports 18 and 19. Here, the outer peripheral side of the blade 3 is formed to have the maximum height dimension H, and the hair transplanted portion 21 is formed in the outer peripheral side region 20, so that the air is sent to the exhaust port 17 due to the outer periphery of the blade 3. Wind noise is reduced and centrifugal fan noise is reduced.

  FIG. 9 shows a second embodiment of the present invention and is an external view of a cooling unit 200 including a centrifugal fan 100. In the figure, a centrifugal fan 100 includes the impeller 1 and the motor 5 described in the first embodiment. The cooling unit 200 here is also disposed on the trunk of a thin casing such as a mobile device.

  Reference numerals 27 and 28 denote a first heat pipe and a second heat pipe as heat transport means for guiding heat to the casing 2 of the centrifugal fan 100. A flat plate-like first heat receiving portion 29 is provided on one side of the first heat pipe 27, and the other side of the first heat pipe 27 is formed of a member having excellent heat conductivity. Preferably, it is thermally connected in the vicinity of the exhaust port 17. Further, a flat plate-like second heat receiving portion 30 is provided on one side of the second heat pipe 28, and the other side of the second heat pipe 28 is a cover made of a member having excellent heat conductivity. 10, preferably in the vicinity of the exhaust port 17. The first heat receiving unit 29 and the second heat receiving unit 30 are thermally connected to an MPU (microprocessor unit) of a mobile device and other heat generating components. Further, 31 is a radiation fin provided at the exhaust port 17.

  In this embodiment, heat from the MPU and other heat generating components is quickly transmitted from the first heat receiving unit 29 and the second heat receiving unit 30 to the first heat pipe 27 and the second heat pipe 28, It is led to the vicinity of the exhaust port 17 in the case 9 and the cover 10. As described above, since the air taken in from the intake ports 18 and 19 is efficiently discharged from the exhaust port 17 through the radiating fins 31, the heat reaching the case 9 and the cover 10 is exchanged by this air, Within the housing, the temperature rise of the MPU and other heat generating components can be suppressed.

  In addition, this invention is not limited to the said Example, It can change in the range which does not deviate from the meaning of this invention. For example, the hair F used for the flocked portion 21 is not limited to synthetic fibers such as nylon, and can be appropriately changed. Further, the method for flocking the hair transplantation part 21 is not limited to electrostatic flocking and can be changed as appropriate. Further, the shapes of the impeller 1 and the blade 3 are not limited to the turbofan type and the sirocco fan type, and can be changed as appropriate.

1 impeller 3 blade 4 boss
14 Shaft
17 Exhaust port (exhaust part)
18 1st inlet (intake part)
19 Second inlet (intake section)
20 region 21 flocked part F hair
H dimension L length

Claims (3)

An exhaust part and a casing are formed in the discharge direction of the impeller, an intake part is formed in a direction perpendicular to the discharge direction of the impeller, and the impeller includes a plurality of blades on the circumferential part of the cup-shaped boss Is a centrifugal fan in which a shaft is attached to the boss, and a flocked portion is formed on the impeller, and the flocked portion is formed on the entire surface of the blade not facing the intake portion. The blade is configured such that no flocking is performed in a region facing the suction portion of the blade, and the non-facing region is the outer peripheral side of the blade, and the height dimension parallel to the shaft is formed to the maximum. centrifugal fan characterized in that it is a region that. The centrifugal fan according to claim 1, wherein the length of the hair in the flocked portion is 2 mm or less. The centrifugal fan according to claim 1 or 2 , wherein the direction of the bristles of the flocked portion is a direction substantially perpendicular to the surface of the blade.

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