JP5392330B2 - 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 intake ports on both sides in a direction perpendicular to the discharge direction of the impeller.

  However, in a mobile device such as a notebook personal computer, not only the centrifugal fan is required to have a higher air volume but also the noise reduction is strongly demanded in recent years as the amount of heat generated by the CPU increases. Further, as the mobile device casing becomes thinner, there is a problem that a sufficient intake space for the centrifugal fan cannot be secured, and the air volume necessary for cooling cannot be obtained.

JP 2004-92446 A

  Therefore, in view of the above problems, an object of the present invention is to provide a centrifugal fan that can be easily sucked even in a thin housing and can be quiet while maintaining the air volume.

In order to achieve the above object, a centrifugal fan according to a first aspect of the present invention is a centrifugal fan positioned in the discharge direction of an impeller and provided with an exhaust port in the casing, wherein the casing corresponds to the discharge direction of the impeller . An air inlet and a projecting stabilizer are provided in a part of the side wall, and the tip of the blade constituting the impeller is formed so as to pass through the center of the impeller .

Centrifugal fan according to claim 2 of the present invention, the blade is separated from the central portion of the impeller, each of said each blade, characterized in that formed in staggered position with respect to the rotational direction.

The centrifugal fan according to claim 3 of the present invention is a centrifugal fan that is located in the discharge direction of the impeller and has an exhaust port in the casing, and is provided with a first intake port in a direction perpendicular to the discharge direction of the impeller. , the part of the side wall of the casing corresponding to blowing direction of the impeller, and the second intake port, the provided protruding stabilizer, the orientation of the tip portion of the blade constituting the impeller, the center of the impeller It is formed to pass through .

Centrifugal fan according claim 4 of the present invention, the blade is separated from the central portion of the impeller, each of said each blade, characterized in that formed in staggered position with respect to the rotational direction.

In the centrifugal fan according to claim 1, the intake port is provided in a part of the side wall of the casing corresponding to the discharge direction of the impeller, thereby reaching the exhaust port from the intake port via the flow path between the impeller and the casing. The flow of wind can be formed in a straight line. Therefore, even in a thin housing, it is possible to easily intake air from the intake port and maintain the air volume necessary for cooling. In addition, the centrifugal fan here has significantly lower noise than the conventional fan for the air volume required for cooling, and can be quiet. Further, by providing a protruding stabilizer on a part of the side wall of the casing, it is possible to determine the amount and direction of air discharged from the exhaust port, and to obtain a preferable amount of air as a centrifugal fan.

Furthermore , by making the blades that make up the impeller substantially in the middle of the forward and reverse blades, air can be sucked in efficiently from the intake port by the rotation of the impeller, and the wind can be smoothly sent out to the exhaust port. It is possible to expect an increase in air volume.

In the centrifugal fan according to the second aspect , the blades separated from the central portion of the impeller are provided at alternate positions with respect to the rotation direction of the impeller, so that the intake air is efficiently sucked from the intake port by the rotation of the impeller. However, it is possible to smoothly send wind to the exhaust port, and an increase in air volume can be expected.

In the centrifugal fan according to claim 3 , by providing the second intake port in a part of the casing side wall corresponding to the discharge direction of the impeller, the second intake port passes through the flow path between the impeller and the casing. Thus, the flow of wind reaching the exhaust port can be formed in a straight line. Therefore, even if a sufficient intake air volume cannot be obtained from the first intake port provided in the direction perpendicular to the discharge direction of the impeller in the thinned casing, another second intake air Air can be easily sucked from the mouth to maintain the air volume necessary for cooling. In addition, the centrifugal fan here has significantly lower noise than the conventional fan for the air volume required for cooling, and can be quiet. Further, by providing a protruding stabilizer on a part of the side wall of the casing, it is possible to determine the amount and direction of air discharged from the exhaust port, and to obtain a preferable amount of air as a centrifugal fan.

Furthermore , by making the blades constituting the impeller substantially in the middle of the forward blades and the reverse blades, the intake wheel can be efficiently sucked from the first and second intake ports by the rotation of the impeller, and smoothly discharged to the exhaust port. It is possible to send wind to the air, and an increase in air volume can be expected.

In the centrifugal fan according to claim 4 , since the respective blades separated from the central portion of the impeller are provided at alternate positions with respect to the rotation direction of the impeller, the first and second intake ports are rotated by the rotation of the impeller. As a result, the air can be sent out smoothly to the exhaust port while efficiently taking in air, and an increase in the air volume can be expected.

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 explanatory drawing which represents the blade shape of an impeller same as the above. It is a graph which shows how air volume changes with respect to the gap with a housing in a conventional product and the centrifugal fan of this invention same as the above. It is a graph which shows how a noise changes with respect to the maximum air volume in a conventional product and the centrifugal fan of this invention. It is a principal part external view of the centrifugal fan in the state which removed the cover which shows 2nd Example of this invention. It is an external view of the cooling unit containing the centrifugal fan which shows 3rd Example of this invention.

  Hereinafter, preferred embodiments of the centrifugal fan according to the present invention will be described in order with reference to the accompanying drawings. In addition, the same code | symbol is attached | subjected to the location which is common in each Example, and description of a common part is abbreviate | omitted as much as possible in order to avoid duplication.

  1 to 7 show a first embodiment of the present invention. First, the overall configuration of the centrifugal fan 100 will be described with reference to FIGS. 1 to 4. Reference numeral 1 denotes a rotating impeller, and reference numeral 2 denotes a blade. It is a casing provided with a car 1 inside. The impeller 1 is composed of a plurality of blades 3 serving as blades and a cup-shaped impeller 4, and the blades 3 serving as centrifugal fan bodies are radially arranged around the circumference of the impeller 4 that forms the center of the impeller 1. It is formed. Further, a motor 5 serving as a driving unit for the impeller 1 is disposed inside the impeller 4. The motor 5 includes a stator 6 having an iron core (core) on which windings are mounted, a rotor (yoke) 7 that is attached to the inner peripheral portion of the impeller 4 and rotates by a magnetic force from the stator 6, the stator 6 and other The circuit board 8 which comprises each element and comprises the electric circuit as the motor 5 is comprised.

  The casing 2 that forms the outline of the centrifugal fan 100 includes a bottomed case 11 that surrounds the impeller 1 and a cover 12 that covers the upper opening of the case 11, both of which are formed of members having excellent thermal conductivity. Is done. In addition, the case 11 is formed with an island-shaped motor mounting wall 14 connected to the periphery thereof by spokes 13. The motor 5 is installed on the motor mounting wall 14, and the motor 5 excluding the motor mounting wall 14 side. Is surrounded by a cup-shaped impeller 4. More specifically, a cylindrical bearing tube 15 is press-fitted and fixed to the motor mounting wall 14 which is a motor mounting portion, while a shaft 16 which is a rotating shaft is mounted at the center of the impeller 4. Is supported by a bearing 17 in a bearing tube 15 so as to be rotatable. The rotor 7 and the impeller 1 rotate around the shaft 16 by an electromagnetic action between the magnet 18 attached to the inner peripheral surface of the rotor 7 and the stator 6 facing the magnet 18. Reference numeral 19 denotes a lead wire for electrical connection with the stator 6.

  The motor mounting wall 14 forms a part of the case 11, and the case 11 has an exhaust port 21 and a casing 2 formed in the same direction as the discharge direction of the impeller 1. In addition, an air inlet 22 is formed in the case 11 in a direction perpendicular to the discharge direction of the impeller 1, and the cover 12 attached to the case 11 so as to face the air inlet 22 is also attached to the case 11. Another intake port 23 is formed in a direction perpendicular to the discharge direction. The intake port 22 is formed by partially connecting the motor mounting wall 14 of the case 11 and the peripheral portion with the spokes 13. Further, the opening areas of the intake ports 22 and 23 may be appropriately determined in consideration of the intake amount of each intake port 22 and 23. The exhaust port 21 of the centrifugal fan 100 is located on one side of the discharge direction along the radial direction of the impeller 1 and is formed in the side wall of the casing 2 formed in a box shape. A plurality of other air inlets 24 and 25 are formed in the side wall of the casing 2 located on the opposite side of the discharge direction with the motor 5 interposed therebetween. As a result, in the radial direction of the impeller 1, a linear air passage 27 that circulates outside the impeller 1 from the intake ports 24 and 25 to the exhaust port 21 is formed.

  As shown in FIG. 4, an appropriately shaped stabilizer 28 is provided inside the casing 2 where the air passage 27 is formed. The stabilizer 28 is used to obtain an air volume required for the centrifugal fan 100. In particular, in this embodiment, the stabilizer 28 is provided at a position where the flow of air in the reverse direction from the air passage 27 toward the air inlet 24 is blocked. A shaped stabilizer 28 is provided. Of course, the stabilizer 28 may be provided at a position different from that in FIG. 4, or a plurality of stabilizers 28 may be provided.

  Further, each blade 3 may have a structure in which the base end is directly connected to the outer peripheral surface of the impeller 4, or the base end may be separated from the outer peripheral surface of the impeller 4. In the latter case, a rectifying plate 29 is connected between the blade 3 and the impeller 4, in particular, rectifying the air taken in from the intake ports 22 and 23 and sending it evenly between the blades 3 (see FIG. 4).

  FIG. 5 schematically shows the shape of the blade 3 employed in this embodiment. Further, for comparison, a conventionally known turbofan blade 3A and a sirocco fan blade 3B are also shown for comparison. When the impeller 4 and thus the impeller 1 rotate in the direction of arrow R, the tip of the blade 3A of the turbofan is directed in the direction opposite to the direction of rotation of the impeller 4 (reverse blade). Conversely, the blade 3B of the sirocco fan has its tip pointed in the same direction as the rotation direction of the impeller 4 (forward wing). The blade 3 of the centrifugal fan 100 employed in this embodiment has its tip directed to a straight line α that extends in the radial direction through the rotation axis C of the impeller 1. Due to the shape of the blade 3, when the impeller 1 rotates, not only the intake ports 22 and 23 provided in the rotation axis direction of the impeller 1 but also the intake ports 24 and 23 provided in the radial direction orthogonal to the rotation axis. 25, it is possible to efficiently suck in air (fluid) and increase the air volume.

  Thus, since the motor 5 is arranged almost inside the impeller 1, the centrifugal fan 100 as in the present embodiment can be mounted on a thin casing desired for mobile devices such as notebook computers. Is the most suitable shape.

  Next, the effect | action is demonstrated about the said structure. 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. 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 R by the electromagnetic action between the stator 5 and the magnet 18 attached to the inner peripheral surface of the rotor 7, Warm air existing in the gap between the upper surface of the casing 2 and the gap between the casing and the lower surface of the casing 2 is sucked from the intake ports 22 and 23, and warm air existing between the casing and the side surface of the casing 2. Air is sucked from the separate inlets 24 and 25. The air taken in from the intake ports 22 and 23 is rectified by the rectifying plate 29 of the impeller 1 and sent out to the air passage 27 from between the rotating blades 3, and from the exhaust port 21 to the outside of the centrifugal fan 100 and the casing. Discharged. In addition, the air taken in from the other intake ports 24 and 25 circulates around the outside of the impeller 1 along the air passage 27 formed in the casing 2 to reach the exhaust port 21, and from there, the centrifugal fan 100. As a result, it is discharged outside the housing. At that time, the reverse flow of the wind from the air passage 27 toward the intake port 24 is blocked by the stabilizer 28 provided in the case 11 and guided toward the exhaust port 21, and as a result, the exhaust port 21. It becomes possible to increase the air volume from.

  By the way, in recent years, the casing of a mobile device has been thinned, and intake from a direction perpendicular to the discharge direction of the impeller 1 has become extremely difficult. Therefore, since the centrifugal fan 100 of the present invention has the air inlets 24 and 25 formed in a part of the casing 2 corresponding to the discharge direction of the impeller 1, even if the gap between the housing and the centrifugal fan 100 is reduced, the air inlet The required amount of intake air is obtained from 24 and 25, and the air volume necessary for cooling can be maintained. In addition, when comparing the noise at the same air volume required for cooling, the centrifugal fan 100 of the present invention significantly reduces the noise, and can greatly contribute to the noise reduction desired in recent years.

  FIG. 6 shows a comparison of air flow characteristics at the same noise between the conventional product and the centrifugal fan 100 of the present invention. In this figure, the influence of the gap between the casing 2 and the housing on the air volume is shown. However, the centrifugal fan 100 of the present invention has an air volume that decreases as the gap between the casing 2 and the housing decreases. You can see that it has improved.

  FIG. 7 compares the noise characteristics with respect to the air volume between the conventional product and the centrifugal fan 100 of the present invention under the condition that the gap between the casing 2 and the casing is 1.5 mm. As is apparent from this figure, it can be seen that when the air volume is 68 L / min, the noise is reduced by 8 db between the conventional product and the present invention.

  As described above, in the present embodiment, in the centrifugal fan 100 which is located in the discharge direction of the impeller 1 and has the exhaust port 21 provided in the side wall of the casing 2, the intake ports 24 and 25 are formed in a part of the side wall of the casing 2. Is provided.

  If it carries out like this, by providing the inlet ports 24 and 25 in a part of side wall of the casing 2 which corresponds to the discharge direction of the impeller 1, the wind path which is a flow path between the inlet ports 24 and 25 between the impeller 1 and the casing 2 The flow of the wind that reaches the exhaust port 21 via 27 can be formed in a straight line. Therefore, even in a housing such as a thin mobile device, it is possible to easily intake air from the intake ports 24 and 25 and maintain the air volume necessary for cooling. Further, the centrifugal fan 100 here has a significantly lower noise than the conventional fan for the amount of air necessary for cooling, and can be quiet.

  Further, particularly in the present embodiment, the first intake ports 22 and 23 are provided in a direction perpendicular to the discharge direction of the impeller 1, and other second intake ports 24 and 25 are provided in a part of the side wall of the casing 2. Therefore, even when a sufficient intake air volume cannot be obtained from the first intake ports 22 and 23 provided in the direction perpendicular to the discharge direction of the impeller 1, another second intake port 24 is provided. , 25, the air volume required for cooling can be maintained. In addition, the centrifugal fan here has significantly lower noise than the conventional fan for the air volume required for cooling, and can be quiet.

  Here, it is preferable to provide a plurality of the first intake ports 22 and 23 and the second intake ports 24 and 25 as in the present embodiment. The air volume can be increased.

Further, in the present embodiment, a protruding stabilizer 28 is provided on a part of the side wall of the casing 2. In this way, the amount and direction of air discharged from the exhaust port 21 can be determined by the position and shape of the stabilizer 28, and a preferable amount of air as the centrifugal fan 100 can be obtained.

  Furthermore, in the present embodiment, the direction of the tip portion of the blade 3 constituting the impeller 1 is formed on a straight line passing through the rotation axis center C that is the center of the impeller 1. In this way, the blade 3 constituting the impeller 1 has a substantially intermediate shape between the forward blade and the reverse blade, and the efficiency of the first intake ports 22 and 23 and the second intake ports 24 and 25 is increased by the rotation of the impeller 1. The air can be smoothly sent out to the exhaust port 21 while performing a good intake, and an increase in the air volume can be expected.

  FIG. 8 is an external perspective view of the centrifugal fan 100 according to the second embodiment of the present invention with the cover 12 removed. In the figure, the blades 31 and 32 forming the tip of the impeller 1 are alternately formed in different shapes. The blades 31 and 32 have different heights along the rotation axis direction of the impeller 1, and are formed such that the blade 31 is higher than the blade 32. In the present embodiment, one blade 32 is provided between adjacent blades 31, 31 arranged on the circumference, but two or more blades 32 may be provided, for example. Other configurations are the same as those in the first embodiment.

  The centrifugal fan 100 according to the present embodiment separates the blades 31 and 32 constituting the impeller 1 from the cup-shaped impeller 4 which is the central portion of the impeller 1, and between the blades 31 and 32 and the impeller 4. A current plate 29 is provided, and the blades 31 and 32 are formed at alternate positions with respect to the rotation direction. In this way, the blades 31 and 32 separated from the impeller 4 of the impeller 1 are provided at alternate positions with respect to the rotation direction of the impeller 1, so that they are taken in from the intake ports 22 and 23 by the rotation of the impeller 1. The rectified air is rectified by the rectifying plate 29 of the impeller 1, sent out from between the rotating blades 31, 32 toward the exhaust port 21, and the air taken in from the other intake ports 24, 25 is shaped. The blades 31 and 32 having different diameters efficiently circulate around the outside of the impeller 1 and are sent to the exhaust port 21. As a result, not only the first intake ports 22 and 23 but also the second intake ports 24 and 25 can efficiently intake air, and the wind can be smoothly sent to the exhaust port 21 to increase the air volume. Can be expected.

  In addition, since the shape of each blade 31 and 32 and the point provided with the stabilizer 28 are the same as those in the first embodiment, the description thereof is omitted here.

  FIG. 9 is an external view of the cooling unit 200 including the centrifugal fan 100 according to the third embodiment of the present invention. In the figure, the centrifugal fan 100 includes the impeller 1 and the motor 5 described in the first and second embodiments. However, because the impeller 1 and the motor 5 are attached to the cover 11 instead of the case 12, the air inlet 22 is formed in the case 12 and the air inlet 23 is formed in the cover 11. The cooling unit 200 here is also disposed inside a thin housing such as a mobile device.

  Reference numeral 41 denotes a heat pipe as heat transport means for guiding heat to the casing of the centrifugal fan 100, and a flat plate-like first heat receiving part 42 and second heat receiving part 43 are provided on one side of the heat pipe 41. The other side of the heat pipe 41 is thermally connected to the upper surface of the cover 12 made of a member having excellent thermal conductivity, preferably located near the exhaust port 21. The first heat receiving unit 42 and the second heat receiving unit 43 are thermally connected to an MPU (microprocessor unit) of a mobile device and other heat generating components.

  In this embodiment, heat from the MPU and other heat generating components is quickly transferred from the first heat receiving portion 42 and the second heat receiving portion 43 through the heat pipe 41 to the vicinity of the exhaust port 21 in the cover 12. It is burned. As described above, since the air taken in from each of the intake ports 22 to 25 is efficiently discharged from the exhaust port 21, the heat reaching the cover 12 is exchanged by this air, and MPU and other heat generation in the housing. The temperature rise of components can be suppressed.

  In addition, this invention is not limited to said each Example, It can change in the range which does not deviate from the meaning of this invention.

DESCRIPTION OF SYMBOLS 1 Impeller 2 Casing 21 Exhaust port 22, 23 Intake port (1st intake port)
24, 25 Air intake (second air intake)
28 Stabilizer 31, 32 Blade

Claims (4)

In the centrifugal fan located in the discharge direction of the impeller and provided with an exhaust port in the casing,
In a part of the side wall of the casing that corresponds to the blowing direction of the impeller , an air inlet and a protruding stabilizer are provided ,
A centrifugal fan , wherein the tip of the blade constituting the impeller is formed so as to pass through the center of the impeller . Before separating the Kivu blade from the center of the impeller, the centrifugal fan according to claim 1, characterized by forming staggered position each of said each blade with respect to the rotational direction. In the centrifugal fan located in the discharge direction of the impeller and provided with an exhaust port in the casing,
Providing a first air inlet in a direction perpendicular to the discharge direction of the impeller;
Some of the side wall of the casing corresponding to blowing direction of the impeller, and the second intake port, the protruding stabilizer provided,
A centrifugal fan , wherein the tip of the blade constituting the impeller is formed so as to pass through the center of the impeller . Pre Kivu blade separated from the central portion of the impeller, the centrifugal fan according to claim 3, characterized by forming staggered position each of said each blade with respect to the rotational direction.