TWI667416B - Fan blade structure and centrifugal fan - Google Patents

Abstract

A fan blade structure and a centrifugal fan, the centrifugal fan includes a casing having a first air inlet and an air outlet, and a blade structure received in the casing, the blade structure including a hub and a plurality of blades on an outer peripheral side of the hub, each blade having a first portion and a second portion, the first portion and the second portion having a vertically extending virtual straight line, the first portion having a surface area greater than or less than the first portion The surface area of the two portions, between one side of the second portion of the blade and the inner side of the side wall of the housing, forms an outer space that is not perpendicular to a first air inlet surface where the first air inlet is located.

Description

Fan blade structure and centrifugal fan

The invention relates to a fan blade structure and a centrifugal fan, in particular to a blade structure and a centrifugal fan which can improve the smoothness of the flow field and improve the overall efficiency of the centrifugal fan.

The current electronic industry is developing rapidly, and the performance of electronic components is constantly improving. As the speed of operation increases, the heat generated by it will generate relatively large amounts of heat. If the heat cannot be immediately dissipated, the computing power of the electronic component will be If it is lowered, it will cause burnt, so it will be used as a heat release through a centrifugal fan in a limited system space.

Referring to the first, second, and second embodiments, the conventional centrifugal fan 1 mainly includes a frame 11 and a blade 12. The upper portion 111 and the lower portion 112 of the frame 11 have an air inlet 13 respectively. The upper side 111 and the side 113 of the lower portion 112 have an air outlet 14 which is the same as the air inlet surface 13a where the air inlet 13 of the lower portion 112 is located, and the side edge 113 is opposite to the upper portion 111 and the lower portion 112, respectively. Vertically, the housing 11 is provided with an accommodating space 114 for accommodating the fan blade 12, and between the blade 12 and the side edge 113, a first-class channel 15 is formed, and the flow channel 15 and the air inlet 13 of the upper portion 111 ( The upper air inlet surface 13a (or the lower air inlet surface 13a) where the air inlet 13) of the lower portion 112 is located is perpendicular. The blade 12 includes a hub 121 and a plurality of blades 122 disposed on an outer side of the hub 121. The blades 122 are spaced apart from the side 1211 of the hub 121 and above the upper 111 (or lower 112) of the corresponding frame 11. The wind surface 13a (or the lower air inlet surface 13a) is perpendicular. Therefore, when operating, the surrounding air flows through the blades 122 of the blade 12 to drive the surrounding air to flow, and the axial airflow entering from the air inlet 13 is diverted from the radial airflow along the hub and then discharged from the air outlet 14.

The size of the centrifugal fan 1 in a general system (such as a notebook computer, smart mobile phone, in-vehicle system, all-in-one (AIO), mini system or IPAD) is mainly selected according to the system. The shortest side height is used to confirm the size of the centrifugal fan 1, but it is very difficult to select the centrifugal fan 1 for the irregular system. There are two cases: the first case is when the fan size is large, it will interfere with the inside of the system. The shortest side height of an electronic component or other device, such as an irregular system, may be suitable for use with a centrifugal fan such as a 3-inch centrifugal fan, but interferes with the electronic components or other devices inside the system (such as heat sinks or hard disk devices) or the shape of the system. Therefore, it is impossible to use a centrifugal fan of a suitable size; in the second case, the selection of a small fan size may result in insufficient performance (for example, the air volume is insufficient to meet the heat dissipation requirement), so that the dummy fan is equivalent to wasting the foregoing. The system space of the fan, such as the irregular system, is affected by the interference of internal electronic components or other devices, so that only a small one can be selected. The heart fan is used, but the air volume blown by the 1吋 centrifugal fan is insufficient to quickly dissipate heat to the entire system, resulting in poor overall heat dissipation performance of the system.

It is an object of the present invention to provide a blade structure and a centrifugal fan that can achieve improved fan efficiency.

Another object of the present invention is to provide a blade structure and a centrifugal fan which can increase the plurality of blade areas to effectively increase the air volume.

Another object of the present invention is to provide a structural design that changes the shape of a casing and the first and second air inlets thereof to improve the flow field condition (such as the smoothness of the flow field), thereby A centrifugal fan that effectively improves heat dissipation efficiency.

Another object of the present invention is to provide a fan that can design the shape of a centrifugal fan and the shape of a blade flow path between a plurality of blades in accordance with system requirements, thereby effectively utilizing the space in the system and the fan for improving heat dissipation performance. Leaf structure and centrifugal fan.

In order to achieve the above object, the present invention provides a blade structure for a centrifugal fan, the blade structure including a hub and a plurality of blades, the blades being disposed on an outer peripheral side of the hub, Each blade has a first portion and a second portion, and the first portion and the second portion have a vertically extending virtual straight line, and the second portion is formed to extend outward from an end of the first portion adjacent to the virtual straight line. And the surface area of the first portion is larger or smaller than the surface area of the second portion; and the fan blade structure design of the present invention effectively achieves the effect of improving heat dissipation.

The present invention further provides a centrifugal fan including a casing and a blade structure, the casing is provided with an upper cover, a base and a shaft seat, the upper cover is disposed on the base, and the upper cover and the base define a capacity a accommodating space of the axle seat, a first air inlet opening is formed on the upper cover or the base, and communicates with the accommodating space, the base is provided with a bottom plate and a side wall extending from the bottom plate, the side wall is provided with at least An air outlet, the at least one air outlet is connected to the accommodating space, and the blade structure is pivoted with the shaft seat in the accommodating space, the blade structure comprises a hub and a plurality of blades, wherein the blades are disposed at The outer peripheral side of the hub has a first portion and a second portion, and the first portion and the second portion have a vertically extending virtual straight line, and the second portion is adjacent to the virtual straight line One end of the portion is formed to extend outwardly, and the surface area of the first portion is larger or smaller than the surface area of the second portion, and a side of the second portion of the blade and an inner side of the side wall facing the housing are formed The first air inlet surface of the air inlet is not perpendicular to the outer space; the centrifugal fan design of the invention can effectively improve the air volume effect, and effectively improve the flow field condition, thereby effectively improving the fan efficiency and improving Cooling performance.

2‧‧‧Fan leaf structure

20‧‧·wheels

201‧‧‧Connecting Department

203‧‧‧Magnetic parts

21‧‧‧ leaves

211‧‧‧The first part

2111‧‧‧ top side

2112‧‧‧ side

2113‧‧‧Bottom

212‧‧‧Part II

2121, 2122, 2123‧‧‧ first, second and third sides

214‧‧‧ Windward side

2141, 2142‧‧‧First and second windward areas

215‧‧‧ leeward

2151, 2152‧‧‧ first and second leeward areas

216‧‧‧blade runner

23‧‧‧Axis

L‧‧‧ virtual straight line

3‧‧‧ Centrifugal fan

31‧‧‧Shell

311‧‧‧Upper cover

312‧‧‧Base

3121‧‧‧floor

3122‧‧‧ Sidewall

313‧‧‧ shaft seat

314‧‧‧ accommodating space

315, 316‧‧‧ first and second air inlets

315a, 316a‧‧‧ first and second into the wind

317‧‧‧air outlet

318‧‧‧Outside space

33‧‧‧ Stator

Figure 1 is a schematic exploded perspective view of the prior art.

Figure 2A is a schematic diagram of a stereo combination of the prior art.

Figure 2B is a schematic cross-sectional view of a conventional combination.

Fig. 3A is a perspective view showing the structure of the blade of the first embodiment of the present invention.

Fig. 3B is a schematic cross-sectional view taken along line A-A of Fig. 3A.

Fig. 4A is a schematic view showing an embodiment of a blade structure according to a first embodiment of the present invention.

Fig. 4B is a schematic view showing another embodiment of the blade structure of the first embodiment of the present invention.

Fig. 5 is a perspective view showing the blade structure of the second embodiment of the present invention.

Figure 5A is a cross-sectional view of the B-B of Figure 5 of the present invention.

Fig. 5B is a schematic view showing an embodiment of a blade structure according to a second embodiment of the present invention.

FIG. 5C is a schematic view showing another embodiment of the blade structure according to the second embodiment of the present invention.

Figure 6 is a perspective exploded view of the centrifugal fan of the third embodiment of the present invention.

Fig. 7A is a perspective view showing the three-dimensional combination of the centrifugal fan of the third embodiment of the present invention.

Figure 7B is a cross-sectional view taken along line C-C of Figure 7A of the present invention.

The above object of the present invention, as well as its structural and functional features, will be described in accordance with the preferred embodiments of the drawings.

The present invention is a fan blade structure and a centrifugal fan. Please refer to FIG. 3A for a perspective view of the blade structure of the first embodiment of the present invention; FIG. 3B is a schematic cross-sectional view of the AA of FIG. 3A; FIG. 4B is a schematic view showing another embodiment of the blade structure of the first embodiment of the present invention. FIG. The blade structure 2 is applied to the centrifugal fan 3 (refer to FIG. 5), the blade structure 2 includes a hub 20 and a plurality of blades 21, and the blades 21 are annularly disposed on the outer circumferential side of the hub 20, Each of the blades 21 has a first portion 211 and a second portion 212. The first portion 211 and the second portion 212 have a vertically extending virtual line L. The second portion 212 is adjacent to the virtual portion. One end of the first portion 211 of the straight line L extends outwardly. The surface area of the first portion 211 in this embodiment is larger than the surface area of the second portion 212, but is not limited thereto. In the specific implementation, the first portion can also be designed. The surface area of portion 211 is less than the surface area of second portion 212.

The first portion 211 has a top edge 2111 and a bottom edge 2113. In this embodiment, the top edge 2111 is parallel to the bottom edge 2113, and the top edge 2111 and one end of the bottom edge 2113 are connected to the outer circumference of the hub. The second side 212 has a first side 2121 and a second side 2122 from the top side 2111. The other end of the second side 2122 is connected to the other end of the second side 2122, and the other end of the second side 2122 is connected to the other end of the horizontally adjacent bottom side 2113, and the virtual line L From the first side 2121 and the other end of the top edge 2111, vertically extending downwardly to the corresponding bottom edge 2113, so that the first and second sides 2121, 2122 of the second portion 212 and the corresponding virtual straight line L It is composed of a triangular shape. It can be seen from FIG. 3A that the surface area (or surface area) of the first portion is the area of all surfaces of the first portion 211 (including the surface of the top edge 2111, the surface of the bottom edge 2113, and the surface of the two sides of the first portion 211). And, the surface area (or surface area) of the second portion 212 is the sum of the areas of all surfaces of the second portion 212 including the first and second sides 2121, 2122 and the two side surfaces of the second portion 212. .

In an embodiment, referring to FIG. 4A, the first side 2121 may be optionally designed to extend outwardly from the other end of the top edge 2111 (eg, inclined downwardly) to extend the end of the second side 2122. The other end of the second side 2122 is obliquely connected to the other end of the adjacent bottom edge 2113, and the first and second sides 2121, 2122 of the second portion 212 and the corresponding virtual straight line L are formed in a triangular shape. In another embodiment, referring to FIG. 4B, the first and second sides 2121, 2122 of the second portion 212 are designed to have an irregular wave shape.

Each of the blades 21 is provided with a windward surface 214 and a pair of leeward faces 215 that are to face the windward surface 214. The windward surface 214 and the leeward surface 215 are respectively disposed on two sides of the blade 21, during the operation of the blade structure 2. (such as reverse time) The needle is rotated. One side of the blade structure 2 facing the rotation direction is the windward surface 214, and the other side is the leeward surface 215, and the windward surface 214 is located in front of the leeward surface 215. In addition, the windward surface 214 defines a first windward surface area 2141 and a second windward surface area 2142 that tapers outwardly from the first windward surface area 2141. The first and second windward surface areas 2141, 2142 are respectively located. One side of the first and second portions 211, 212, that is, the first windward surface area 2141 is located on a side of the first portion 211 between the virtual straight line L and the outer peripheral side of the hub 20, the second windward side The area 2142 is located on a side of the virtual line L and the second portion 212 between the first and second sides 2121, 2122, and the shape of the first windward surface area 2141 of the first portion 211 and the second portion 212 The shape of the second windward surface area 2142 is different. For example, the shape of the first windward surface area 2141 of the first portion 211 is rectangular, and the shape of the second windward surface area 2142 of the second portion 212 is triangular. The shape is such that the overall shape of the blade 21 is a trapezoidal shape, but the shape of the blade 21 is not limited thereto.

The leeward surface 215 defines a first leeward surface area 2151 and a second leeward surface area 2152 that tapers outwardly from the first leeward surface area 2151. The first and second windward surface areas 2141, 2142 respectively correspond to the first And two leeward areas 2151, 2152, the first and second leeward areas 2151, 2152 are respectively located on the other side of the first and second parts 211, 212, and the first leeward area 2151 is located on the virtual straight line L and The second leeward region 2152 is located at the other side of the first portion 211 between the outer peripheral sides of the hub 20, and the second leeward region 2152 is located at the second portion 212 between the virtual line L and the first and second sides 2121, 2122. a side surface, and the shape of the first leeward surface area 2151 of the first portion 211 is different from the shape of the second leeward surface area 2152 of the second portion 212, for example, the shape of the first leeward surface area 2151 of the first portion 211 is The second leeward area 2152 of the second portion 212 has a triangular shape as in a rectangular shape.

3A and 3B, the hub 20 is provided with a connecting portion 201 which is provided on the bottom side 213 of the blades 21, and the connecting portion 201 is connected to the outer peripheral side of the hub 20. Bottom of blade 21 The side 213 forms a ring body, and a vane flow path 216 is formed between the vanes 21 for flowing airflow (i.e., air fluid) toward the radial direction of the hub 20, and the two vanes 21 The shape of the blade flow path 216 is the same as the shape of any of the blades 21 facing each other, as the shape of each blade 21 is in the shape of a ladder, and the shape of the blade flow path 216 between the two blades 21 at this time. It will also be like a ladder shape.

In an embodiment, the shape of the blade 21 may be designed to be irregular, and the shape of the blade flow path 216 between the two blades 21 may also be in an irregular shape. In another embodiment, the hub 20 can also omit the connecting portion 201.

Therefore, through the structural design in which the shape of the blade runner 216 changes as the shape of the blade 21 changes, the blade runners 216 can change the flow field of the outgoing airflow, so that when the airflow flows out of the blade runners 216, Smoothly flow out, which effectively enhances the effect of wind pressure. In addition, the second windward surface area 2142 and the second leeward surface area 2152 of the blades 21 effectively increase the overall surface area of the blade 21 and expand the area of the blade flow path 216, so that the effect of increasing the air volume is effectively achieved.

Therefore, with the design of the blade structure 2 of the present invention, the effect of increasing the air volume and the wind pressure is effectively achieved, and the effect of improving the heat dissipation is also effectively achieved.

5 is a perspective view of a fan blade structure according to a second embodiment of the present invention; FIG. 5A is a schematic cross-sectional view taken along line BB of FIG. 5; and FIG. 5B is an embodiment of a blade structure according to a second embodiment of the present invention. FIG. 5C is a schematic view showing another embodiment of the blade structure according to the second embodiment of the present invention. The structure and the connection relationship of the blade structure of the present example are the same as those of the blade structure and the connection relationship of the first embodiment, and therefore will not be described again. In this embodiment, the first portion 211 of the first embodiment further includes a side 2112, and the second portion 212 further includes a third side 2123 connected to the first and second sides 2121, 2122. The first portion 211 has the foregoing top edge 2111, the bottom edge 2113 and one side edge 2112. One end of the side edge 2112 is connected to the other end of the top edge 2111, and the second portion 212 has the first edge 2121. And a second side 2122 and a third side 2123 connected to one end of the first and second sides 2121, 2122, the other ends of the first and second sides 2121, 2122 are respectively connected to the other end of the side 2112 and the bottom The other end of the side 2113. As can be seen from FIG. 5, the surface area of the first portion 211 is the area of all the surfaces of the first portion 211 (including the top surface 2111 surface, the bottom side 2113 surface, the side 2112 surface, and the two side surfaces of the first portion 211). And, the surface area of the second portion 212 is the sum of the areas of all surfaces of the second portion 212 including the first, second, and third sides 2121, 2122, 2123 and the two side surfaces of the second portion 212.

And the first windward surface area 2141 and the first leeward surface area 2151 of the windward surface 214 of each blade 21 are respectively located on one side and the other side of the first portion 211 between the virtual straight line L and the outer peripheral side of the hub 20 The second windward surface area 2142 and the second leeward surface area 2152 are respectively located on one side and the other side of the virtual line L and the second portion 212 between the first, second, and third sides 2121, 2122, and 2123. And the shape of the first windward surface area 2141 (or the first leeward surface area 2151) of the first portion 211 is different from the shape of the second windward surface area 2142 (or the second leeward surface area 2152) of the second portion 212. For example, the first windward surface area 2141 (or the first leeward surface area 2151) of the first portion 211 has a rectangular shape, and the second windward surface area 2142 of the second portion 212 (or the second leeward surface area 2152) The shape is as a rectangle. The blade runner 216 between the two blades 21 has the same shape as any of the blades 21 facing.

In one embodiment, referring to FIG. 5B, the other end of the side edge 2112 of the first portion 211 is connected to the other end of the top edge 2111. The other end of the side edge 2112 of the first portion 211 is connected to the other end of the bottom edge 2111. The other ends of the first and second sides 2121, 2122 are respectively connected to the other end of the top edge 2111 and the other end of the side edge 2112.

In another embodiment, referring to FIG. 5C, one side 2112 of the first portion 211 is modified to include two sides 2112, and one ends of the two sides 2112 are respectively connected to the other ends of the top edge 2111 and the bottom edge 2113. The other ends of the first and second sides 2121, 2122 are respectively connected to the other ends of the two side edges 2112.

Therefore, the above embodiments are designed such that the shape of the blade runner 216 changes as the shape of the blade 21 changes, so that the blade runners 216 can change the flow field of the outgoing airflow, allowing the airflow to flow through the blade runners. When flowing out in 216, it flows out more smoothly, which effectively increases the effect of wind pressure. In addition, the second windward surface area 2142 and the second leeward surface area 2152 of the blades 21 effectively increase the overall surface area of the blade 21 and expand the area of the blade flow path 216, so that the effect of increasing the air volume and the wind pressure is effectively achieved, and It also effectively improves the heat dissipation effect.

6 is a perspective exploded view of a centrifugal fan according to a third embodiment of the present invention; FIG. 7A is a perspective view showing a three-dimensional combination of a centrifugal fan according to a third embodiment of the present invention; and FIG. 7B is a schematic cross-sectional view of the CC of FIG. And supplemented by referring to Figure 3A. The centrifugal fan 3 includes a casing 31 and a blade structure 2, wherein the structure, connection relationship and function of the blade structure 2 are the same as those of the blade structure 2 of the first embodiment, I will not repeat them here. The housing 31 is substantially ladder-shaped in this embodiment, but is not limited thereto. The housing 31 is provided with an upper cover 311, a base 312, a first air inlet 315, and a first air inlet 315. a first air inlet surface 315a, at least one air outlet 317, and a shaft seat 313. The upper cover 311 is disposed on the base 312, and the upper cover 311 and the base 312 define an accommodating space 314. The first air inlet 315 is disposed on the upper cover 311 or the base 312 of the housing 31, and the first air inlet 315 of the embodiment is opened therethrough. The upper cover 311 is connected to the accommodating space 314. The first air inlet surface 315a is on the same horizontal plane as the outer surface of the upper cover 311. The first air inlet surface 315a and the second portion 212 corresponding to the blade 21 are corresponding. One side 2121 is not vertical.

The base 312 has a bottom plate 3121 and a side wall 3122 extending from the bottom plate 3121. The shaft base 313 is disposed at the center of the bottom plate 3121 in the accommodating space 314 and has an axis corresponding to the fan blade structure 2. The core 23 is pivoted, and the hub 20 of the blade structure 2 has a magnetic member 203 and correspondingly sleeved on the shaft seat 313. The upper 33 phase of the upper sense is excited. In the embodiment, the side wall 3122 is obliquely extended from the periphery of the adjacent bottom plate 3121 toward the accommodating space 314. The upper end of the side wall 3122 is connected to the side corresponding to the upper cover 311. The upper cover 311 and the bottom plate 3121 of the body 31 are not perpendicular to the side wall 3122, respectively. The cross-sectional shape of the side wall 3122 of the housing 31 of the present embodiment is the same as the cross-sectional shape of the first side 2121 of the second portion 212 corresponding to the blade 21, such as the cross-sectional shape of the side wall 3122 of the housing 31 and the like. The cross-sectional shape of the first side 2121 of the blade 21 is inclined in the same direction (or stepped or other shape), so that the overall shape of the casing 31 is irregular. The surface area of the upper cover 311 (ie, the sum of the areas of all surfaces of the upper cover 311) is smaller than the surface area of the bottom plate 3121 (ie, the sum of the areas of all surfaces of the bottom plate 3121).

In an alternative embodiment, the cross-sectional shape of the side wall 3122 of the housing 31 can be modified to be the same as the cross-sectional shape of the first and second sides 2121, 2122 of the second portion 212 of the corresponding blade 21.

In addition, the side wall 3122 is provided with the air outlet 317, and the air outlet 317 is connected to the accommodating space 314, and is used for discharging the airflow in the casing 31, and the inner side of the side wall 3122 of the casing 31 faces the surface. An outer space 318 is formed between one side (such as the first side 2121) of the second portion 212 of the blade 21 of the blade structure 2, and the outer space 318 and the first air inlet surface 315a where the first air inlet 315 is located It is not perpendicular, and the cross-sectional shape of the outer space 318 in this embodiment is inclined (as shown in FIG. 7B), but is not limited thereto. In a specific implementation, the outer space 318 may follow the shell of the centrifugal fan 3. The shape of the body 31 changes and the shape changes. Therefore, the centrifugal fan 3 of the present invention is applied to a system (such as a notebook computer, a smart mobile phone, an in-vehicle system, an all-in-one (AIO), a mini system, a smart wearable device, or an IPAD; The housing 31 of the centrifugal fan 3 can change the outer shape (such as the trapezoidal shape) of the housing 31 as the system changes, and the shape of the blade 21 (such as the ladder shape) of the blade structure 2 is The shape of the outer space 318 (i.e., the cross-sectional shape of the outer space 318) also changes as the outer shape of the outer casing 31 changes, so that the centrifugal fan 3 structure can be effectively utilized and can be applied to each system to make full use of it. Within the system Space. For example, the space for arranging the centrifugal fan 3 in a system is preferably a centrifugal fan 3 having a size as large as 4 ,, but a certain part of the centrifugal fan 3 (such as the upper right half of the centrifugal fan 3) is subjected to electronic components in the system or The interference of other devices (such as a heat sink or a hard disk) or the shape of the system, at this time, the shape of the casing 31 of the centrifugal fan 3 of the present invention is changed, for example, the side wall 3122 of the casing 31 is inclined upward and upward toward the upper cover 311 and The upper cover 311 and the bottom plate 3121 have different surface areas, so as to effectively avoid the interference, so that the system can still use the centrifugal fan 3 to obtain better heat dissipation, so that the performance of the system can be effectively improved.

The housing 31 is provided with a pair of second air inlets 316 that should be the first air inlet 315 and a second air inlet surface 316a of the second air inlet 316. The second air inlet 316 is opened on the bottom plate 3121. And accommodating the accommodating space 314, and the second air inlet surface 316a is on the same horizontal plane as the outer side of the bottom plate 3121, and the second air inlet surface 316a is not perpendicular to the first side of the second portion 212 of the blades 21. 2121 and the outer space 318, and the first air inlet surface 315a of the embodiment is smaller than the second air inlet surface 316a and the first air inlet 315 is smaller than the second air inlet 316, but is not limited thereto. Therefore, the design of the first wind inlet surface 315a of the upper cover 311 and the second air inlet surface 316a corresponding to the bottom plate 3121 are different in size, so that the flow field smoothness is improved and the effect of increasing the air volume is effectively achieved.

In an alternative embodiment, the surface of the upper cover 311 is larger than the surface area of the bottom plate 3121. The first air inlet surface 315a is larger than the second air inlet surface 316, and the first air inlet 315 is larger or smaller than the second air inlet. 316.

In another alternative embodiment, referring to FIGS. 5A, 5B, and 7B, the cross-sectional shape of the side wall 3122 of the casing 31 of FIG. 7B is modified to be substantially stepped, so that the overall shape of the casing 31 is irregular, and the blade is The structure 2 is modified to select the blade structure 2 of the second embodiment, and the outer space 318 is modified to be formed on the inner side of the side wall 3122 of the casing 31 and the third side facing the second portion 212 of the blades 21. 2123 and the first part Between the side edges 2112 of the 211, or with reference to the 5C, 7B, the cross-sectional shape of the side wall 3122 of the housing 31 of FIG. 7B is substantially convex, so that the overall shape of the housing 31 is irregular, and the outer side The space 318 is modified to be formed between the inner side of the side wall 3122 of the casing 31 and the third side 2123 of the second portion 212 facing the blades 21 and the two sides 2112 of the first portion 211, and the outer space 318 is The first and second air inlet faces 315a, 316a are not perpendicular.

Therefore, with the structural design of the centrifugal fan 3 of the present invention, the efficiency of the centrifugal fan 3 can be effectively improved and the heat dissipation effect can be improved, and the problem that the centrifugal fan of a suitable size cannot be selected in the conventional system can be effectively solved.

Claims (17)

A blade structure is applied to a centrifugal fan, the blade structure includes: a hub and a plurality of blades, the blades are disposed on an outer peripheral side of the hub, and each blade has a first portion and a second portion, Between the first portion and the second portion, there is a vertically extending virtual straight line, and the second portion is formed to extend outward from an end of the first portion adjacent to the virtual straight line, and a surface area of the first portion is larger or smaller than the second portion And the first portion has a top edge, a bottom edge and two side edges, the top edge being connected to one end of the bottom edge on an outer peripheral side of the hub, the top edge being away from the other end of the bottom edge An outer peripheral side of the hub, one end of the two sides is respectively connected to the other end of the top edge and the bottom edge, the second portion has a first side and a second side and is connected to one end of the first side and the second side On the third side, the other ends of the first and second sides are respectively connected to the other ends of the two sides. The fan blade structure according to claim 1, wherein each blade has a windward surface and a pair of leeward faces that should face the windward surface, the windward surface defining a first windward surface area and a first windward direction a second windward surface region which is outwardly tapered, wherein the first and second windward surface regions are respectively located on one side of the first and second portions, and the leeward surface defines a first leeward surface region and a first leeward region The second leeward area is tapered outwardly from the leeward area, and the first and second leeward areas are respectively located on the other side of the first and second portions, and correspond to the first and second windward areas. The blade structure according to claim 1, wherein the blades are formed with a blade flow path formed in the same shape, and the shape of the blade flow path is the same as the shape of the corresponding blade, and the shape of the blade flow path is one. Trapezoidal or irregular shape. The blade structure according to claim 1, wherein the hub is provided with a connecting portion provided on the bottom side of the blades, and the connecting portion is connected along an outer peripheral side of the hub The bottom side of the blade forms a ring. A blade structure is applied to a centrifugal fan, the blade structure includes: a hub and a plurality of blades, the blades are disposed on an outer peripheral side of the hub, and each blade has a first portion and a second portion, Between the first portion and the second portion, there is a vertically extending virtual straight line, and the second portion is formed to extend outward from an end of the first portion adjacent to the virtual straight line, and a surface area of the first portion is larger or smaller than the second portion The first portion has a top edge and a bottom edge, and the top edge and one end of the bottom edge are coupled to the outer peripheral side of the hub, the top edge and the other end of the bottom edge being away from the outer circumference of the hub a second side having a first side and a second side, the first side obliquely extending from the other end of the top side to an end of the second side, and the other end of the second side is obliquely connected Adjacent to the other end of the bottom edge, and the virtual straight line extends vertically downward from the first side and the other end of the top side to the corresponding bottom edge. The blade structure according to claim 5, wherein the first and the second sides of the second portion are irregularly wavy. A centrifugal fan includes: a casing, an upper cover, a base and a shaft seat, wherein the upper cover is disposed on the base, and the upper cover and the base together define a receiving space for receiving the axle seat, a first The air inlet is opened on the upper cover or the base, and communicates with the accommodating space. The base is provided with a bottom plate and a side wall extending from the bottom plate. The side wall is provided with at least one air outlet, and the at least one air outlet is connected to the air inlet. Space; and a leaf structure is pivoted to the shaft seat in the accommodating space, the blade structure includes a hub and a plurality of blades, the blade rings are disposed on an outer circumferential side of the hub, and each blade has a a first portion and a second portion, the first portion and the second portion having a vertically extending virtual straight line, the second portion extending outwardly from an end of the first portion adjacent to the virtual straight line, and the first portion The surface area is larger or smaller than the surface area of the second portion, and a first inlet surface of the first air inlet is formed between one side of the second portion of the blade and the inner side of the side wall facing the housing A vertical outer space. The centrifugal fan of claim 7, wherein the first air inlet is opened on the upper cover, and the first air inlet surface is not perpendicular to one side of the second portion corresponding to the blade. The side wall is obliquely extended from the peripheral edge of the adjacent bottom plate toward the accommodating space to correspond to the upper cover, and the shaft seat is disposed at the center of the bottom plate in the accommodating space. The centrifugal fan of claim 8, wherein the housing is provided with a pair of second air inlets corresponding to the first air inlet and a second air inlet surface of the second air inlet, the second air inlet The second air inlet surface is not perpendicular to one side of the second portion of the blades and the outer space, and is disposed on the bottom plate and communicates with the accommodating space. The centrifugal fan of claim 9, wherein the upper cover has a surface area smaller than a surface area of the bottom plate, and the first air inlet surface is smaller than the second air inlet surface. The centrifugal fan of claim 7, wherein the first portion has a top edge and a bottom edge, and the top edge and one end of the bottom edge are connected to an outer peripheral side of the hub, the top edge and the bottom The other end of the side is away from the outer peripheral side of the hub, the second portion has a first side and a second side, and the first side is obliquely extended from the other end of the top side to connect one end of the second side, and The first side faces the inner side of the side wall of the casing, and the other end of the second side is connected horizontally adjacent The other end of the bottom edge, and the virtual straight line extends vertically downward from the first side to the other end of the top side to the corresponding bottom edge. The centrifugal fan of claim 7, wherein the first portion has a top edge, a bottom edge and a side edge, and the top edge and one end of the bottom edge are connected to an outer peripheral side of the hub, the top The other end of the side and the bottom side are away from the outer peripheral side of the hub, and one end of the side is connected to the other end of the top side, the second part has a first side and a second side and a first and second sides a third side connected to one end of the side, the other ends of the first and second sides are respectively connected to the other end of the side and the other end of the bottom side, and the inner side of the side wall of the housing and the second side facing the blades The aforementioned outer space is formed between the third side of the portion and the side of the first portion. The centrifugal fan of claim 7, wherein the first portion has a top edge, a bottom edge and a side edge, and the top edge and one end of the bottom edge are connected to an outer peripheral side of the hub, the top The other end of the side and the bottom side are away from the outer peripheral side of the hub, and one end of the side is connected to the other end of the bottom side, the second part has a first side and a second side and a first and second sides a third side connected to one end of the side, the other ends of the first and second sides are respectively connected to the other end of the top side and the other end of the side, and the inner side of the side wall of the housing and the second side facing the blades The aforementioned outer space is formed between the third side of the portion and the side of the first portion. The centrifugal fan according to claim 7, wherein the first portion has a top edge, a bottom edge and two side edges, and the top edge and one end of the bottom edge are connected to an outer peripheral side of the hub, the top The other end of the edge and the bottom edge are away from the outer peripheral side of the hub, and one ends of the two sides are respectively connected to the other ends of the top edge and the bottom edge, and the second portion has a first edge and a second edge and a a third side connected to one end of the first and second sides, and the other ends of the first and second sides are respectively connected to the second side The other end of the side, and the outer side of the side wall of the casing and the third side facing the second portion of the blades and the two sides of the first portion are formed with the outer space. The centrifugal fan of claim 7, wherein each of the blades is provided with a windward surface and a pair of leeward faces that should face the windward surface, the windward surface defining a first windward surface region and a first windward surface a second windward surface region which is outwardly tapered, wherein the first and second windward surface regions are respectively located on one side of the first and second portions, the leeward surface defining a first leeward surface region and a first leeward direction The second leeward area is tapered outwardly, and the first and second leeward areas are respectively located on the other side of the first and second portions, and correspond to the first and second windward surface areas. The centrifugal fan according to claim 7, wherein the blades are formed with a blade flow path formed in the same shape as the blade corresponding to the shape of the blade, the shape of the blade flow path being a trapezoid Or irregular shape. The centrifugal fan according to claim 7, wherein the hub is provided with a connecting portion provided on the bottom side of the blades, and the connecting portion connects the blades along an outer peripheral side of the hub The bottom side forms a ring body.