TWI429383B - Cooling fan and frame thereof - Google Patents

Description

Cooling fan and its fan frame

The invention relates to a heat dissipation fan, in particular to a fan frame of a heat dissipation fan.

With the rapid development of electronic technology, the heat-generating electronic components such as the central processing unit are running faster and faster, and the heat generated during operation is correspondingly increased. To dissipate the heat to ensure the normal operation of the electronic components, the industry adopts a fan pair. The electronic components dissipate heat. Conventional fans generally include a frame, a stator, and a rotor. The fan frame includes a disc-shaped base, a frame for receiving the rotor, and a plurality of rod-shaped ribs connecting the base and the outer frame. A central air column is protruded from the center of the base, the bearing is received therein, and the stator is sleeved on the center pillar. The rotor includes a hub, a plurality of blades disposed on the outer circumference of the hub, and a permanent magnet attached to the inner wall of the hub. A rotating shaft extends vertically downward from the center of the hub to form a free end. When combined, the rotating shaft is disposed in the bearing, and the stator is received in the hub. When energized, the magnetic field generated by the stator acts on the permanent magnet of the rotor, causing the rotor to continue to operate, generating wind power to dissipate heat. In order to improve the heat dissipation effect, the industry adopts the method of replacing the rod ribs with vanes to guide the airflow and increase the static pressure. However, in practical applications, the structure is accompanied by great dynamic pressure loss, especially near the base. The boundary layer peeling phenomenon occurs on the suction surface of the stationary blade, so a large amount of energy is consumed, resulting in loss of heat dissipation efficiency.

In view of this, it is necessary to provide an effective reduction of airflow boundary layer peeling Phenomenon, a fan frame that reduces dynamic pressure loss and a cooling fan that uses the frame.

A fan frame includes a base and an outer frame. The axial sides of the outer frame respectively form an air inlet and an air outlet. The base is disposed at the air outlet. The base includes a bottom surface and extends upward from the periphery of the bottom surface. A plurality of vanes are connected between the outer frame and the side wall of the base, and the outer diameter of the side wall gradually decreases toward the air outlet along the air inlet.

A cooling fan includes a base, a stator, a rotor and an outer frame. The stator and the rotor are received in the outer frame, and an air inlet and an air outlet are respectively formed on the axial sides of the outer frame, and the base is disposed at the outer side. At the tuyere, the base includes a bottom surface and a side wall extending upward from the periphery of the bottom surface and surrounding one of the bottom surfaces. The plurality of vanes are connected between the outer frame and the side wall of the base, and the outer diameter of the side wall gradually decreases toward the air outlet along the air inlet. .

In the cooling fan, the outer diameter of the side wall of the base gradually decreases toward the air outlet along the air inlet, thereby forming a gradually expanding flow path between the outer frame and the side wall of the base, thereby effectively reducing the peeling phenomenon of the airflow boundary layer and reducing the gas. Flow pressure loss, thereby improving fan cooling efficiency.

Referring to FIG. 1 and FIG. 2 together, the fan includes a frame 10, a stator 20, a rotor 30 and a pair of bearings 40.

The fan frame 10 has a square shape, and a through hole is formed in the center to accommodate the stator 20 and the rotor 30. The through hole defines an air inlet 17 and an air outlet 18 on the axial sides of the fan frame 10, respectively. Forming a top open-ended truncated base on the side of the air outlet 18 The base 12 includes a circular bottom surface 120 and a truncated side wall 122 extending upward from the outer circumference of the bottom surface 120 and surrounding the bottom surface 120. The outer diameter of the side wall 122 gradually decreases toward the air outlet 18 along the air inlet 17 . The peripheral ring of the side wall 122 is provided with a plurality of vanes 16 which are radially arranged. Each vane 16 includes a proximal end and a distal end. The proximal end is connected to the side wall 122 of the base 12, which is far. The end is connected to the inner wall 102 of the frame of the fan frame 10. A center pillar 14 is protruded from the center of the base 12 toward the air inlet 17 side, and a center hole 140 is formed in the center thereof. An opening 142 having an inner diameter larger than the central hole 140 is formed at each end of the center hole 140 to accommodate the bearing 40.

The stator 20 is sleeved on the center pillar 14 and includes a stator core 24, a coil 26 wound on the stator core 24, and a circuit board 22 electrically connected to the coil 26 to supply power to the coil 26. The stator core 24 is formed by stacking a plurality of layers of silicon steel sheets, and an annular portion is formed in the center of the stator core 24. The inner diameter of the stator core 24 is equivalent to the outer diameter of the center pillar 14 for the center pillar 14 to pass through, as needed, from the annular portion. The outer edge extends an appropriate number of pole claws. The two insulating sheets 28 are respectively mounted on the upper and lower sides of the stator. The insulating sheet 28 is made of a plastic material, and the coil 26 wound around the pole claws of the stator core 24 is separated from the stator core 24, thereby achieving the effect of insulating the two.

The rotor 30 includes an annular hub 32, a permanent magnet 38 attached to the inner wall of the hub 32, and a plurality of blades 34 disposed around the periphery of the hub 32. The hub 32 is provided with a shaft seat 324 and a shaft 36 from the shaft seat 324. Extending vertically downwards forms a free end. The rotating shaft 36 forms a groove 360 on the free end side. The permanent magnets 38 alternately form N and S poles in the circumferential direction, and their polarities are symmetrical. distributed.

When assembled, the stator 20 is sleeved on the center pillar 14, and the bearing 40 is received in the opening 142 at both ends of the center pillar 14. The rotating shaft 36 is received in the bearing 40, and a disc spring is sleeved on the rotating shaft 36. The shaft seat 324 is between the bearing 40 at the upper end of the center pillar 14. The bottom end of the spring has a small diameter and abuts against the inner ring of the bearing 40, and has a large diameter at the top end thereof and abuts against the end of the shaft seat 324. A buckle is sleeved on the recess 360 of the free end of the rotating shaft 36 for limiting the axial movement of the rotor 30. When the fan is in operation, the stator coil 26 generates an induced magnetic field that interacts with the permanent magnet 38 of the rotor 30 to continuously drive the rotor 30 to rotate. When the rotor 30 rotates, the blade 34 presses the airflow at the air inlet 17 to the air outlet. 18, the base 12 has a truncated cone shape to gradually increase the cross-sectional area through which the airflow flows, forming a divergent flow passage, which is beneficial to reduce the boundary layer peeling phenomenon generated by the suction surface 162 of the vane 16 and reduce the gas flow pressure loss. Improve fan cooling efficiency.

3 and FIG. 4 show a second embodiment of the present invention. The base 312 of the present embodiment also has a truncated cone shape. The plurality of vanes 316 are disposed around the periphery of the base 312, and the distal end thereof and the frame of the frame 310 are Walls 302 are connected. This embodiment differs from the previous embodiment in that the height of the vane 316 varies radially, and the height of the vane 316 near the proximal end of the pedestal 312 is less than the height of the distal end thereof, and the distal end of the vane 316 is at the distal end. The bottom surface 320 of the seat 312 is substantially flush, and the end 366 of the stationary blade 316 is coupled to the base 312 below the bottom surface 320 of the base 312. In this embodiment, the base 312 is also tapered, so that the fan forms a divergent flow path, which reduces the boundary layer peeling phenomenon between the blade 316 and the airflow. In addition, as the closer to the pedestal 312 The more easily the boundary layer peeling phenomenon occurs, the height of the vane 316 near the pedestal 312 is reduced, and the air flow of the pressure surface 364 is blown away from the airflow of the suction surface 362 in time to prevent the boundary layer from peeling off.

It is to be understood that the susceptor is not limited to a truncated cone shape, and may be designed to be a conical shape, an arc shape, a streamline shape, a conical curve shape or the like as long as the fan is formed into a divergent flow path. FIG. 5 shows a third embodiment of the present invention. The axial cross section of the fan base 512 is a quadratic curve, and the cross section of the flow path around the fan base 512 is gradually enlarged toward the air outlet 518 along the air inlet 517. It can effectively reduce the peeling phenomenon of the boundary layer of the blade 516 and the fluid, and reduce the wind pressure loss.

FIG. 6 shows a fourth embodiment of the present invention. In this embodiment, the axial cross section of the pedestal 612 is also a quadratic curve. The difference between this embodiment and the third embodiment is that the ring is disposed at the base. The height of the vane 616 around the seat 612 varies radially, the height of the vane 616 near the proximal end of the base 612 is less than the height of the distal end thereof, and the distal end of the vane 616 is substantially flush with the bottom surface 620 of the base 612. The end point 666 of the vane 616 connected to the base 612 is higher than the bottom surface 620 of the base 612.

FIG. 7 shows a fifth embodiment of the present invention. In this embodiment, the side wall 722 of the base 712 has a truncated cone shape near one end of the air outlet 718, but is still cylindrical near one end of the air inlet 717. It can be understood that the side wall 722 of the base 712 is close to the end of the air outlet 718 and can also be designed to be conical, curved, streamlined or quadratic.

FIG. 8 shows a sixth embodiment of the present invention. In this embodiment, the shape of the pedestal 812 is the same as that in the fifth embodiment. The end of the air outlet 818 is tapered, and the end of the air inlet 817 is cylindrical. The difference between the embodiment and the fifth embodiment is that the height of the vane 816 of the fan varies in the radial direction, and the vane 816 The height near the proximal end of the base 812 is less than the height of the distal end, and the distal end of the vane 816 and the base 812 are placed on the bottom surface 820 of the base 812.

In summary, the present invention has indeed met the requirements of the invention patent, and has filed a patent application according to law. However, the above description is only a preferred embodiment of the present invention, and it is not possible to limit the scope of the patent application of the present invention. Equivalent modifications or variations made by persons skilled in the art in light of the spirit of the invention are intended to be included within the scope of the following claims.

Fan frame ‧‧10,310

Inside the wall ‧‧‧102,302

Pedestal ‧‧12,312,512,612,712,812

Bottom ‧ ‧ ‧ 120, 320, 620, 820

Side wall ‧‧‧122, 722, 822

Zhongzhu‧‧14

Center hole ‧‧140

Opening ‧‧‧142

Jing Ye‧‧16, 316, 516, 616

Suction surface ‧‧162,362

Air inlet ‧‧17,517,717,817

Outlet ‧‧18,518,718,818

Stator ‧ ‧ 20

Circuit board ‧‧22

Stator core ‧‧24

Coil ‧‧26

Insulation sheet ‧‧28

Rotor ‧ ‧ 30

Wheel ‧‧32

Shaft seat ‧ ‧ 324

Fan Ye‧‧34

Rotary ‧‧‧36

Groove ‧‧‧360

Pressure surface ‧ ‧ 364

Lower endpoints ‧ ‧ 366, 666, 866

Permanent magnet ‧‧38

Bearing ‧‧40

1 is a schematic cross-sectional view showing a first embodiment of a fan of the present invention.

2 is a perspective view of the fan frame of FIG. 1.

Figure 3 is a cross-sectional view showing a second embodiment of the fan of the present invention.

4 is a perspective view of the fan frame of FIG. 3.

Figure 5 is a cross-sectional view showing a third embodiment of the fan of the present invention.

Figure 6 is a cross-sectional view showing a fourth embodiment of the fan of the present invention.

Figure 7 is a cross-sectional view showing a fifth embodiment of the fan of the present invention.

Figure 8 is a cross-sectional view showing a sixth embodiment of the fan of the present invention.

Inside the wall ‧‧‧102

Bottom ‧ ‧ ‧

Side wall ‧‧122

Suction surface ‧‧162

Claims (10)

A fan frame includes a base and an outer frame. The axial sides of the outer frame respectively form an air inlet and an air outlet. The base is disposed at the air outlet. The improvement is that the base includes a bottom surface. And extending from the periphery of the bottom surface and surrounding one side wall of the bottom surface, a plurality of vanes are connected between the outer frame and the side wall of the base, and the outer diameter of the side wall gradually decreases toward the air outlet along the air inlet. The fan frame according to claim 1, wherein the side wall of the base is a truncated cone shape, a conical shape, a streamline shape, an arc shape, or a quadratic curve shape. The fan frame according to claim 1, wherein the side wall of the base has a tapered curved shape near one end of the air outlet, and a cylindrical shape near one end of the air inlet. The fan frame according to any one of claims 1 to 3, wherein each of the vanes includes a proximal end and a distal end, the proximal end being connected to the side wall of the base, the distal end and the frame The inner walls are connected, and the height of each vane changes radially, and the height of the vane at the proximal end is smaller than the height of the distal end. The fan frame of claim 4, wherein the distal end of each of the vanes is flush with the bottom surface of the base, and the lower end of each of the vane and the base of the base is higher than the bottom of the base. A cooling fan includes a base, a stator, a rotor and an outer frame. The axial sides of the outer frame respectively form an air inlet and an air outlet. The base is disposed at the air outlet, and the stator and the rotor Included in the outer frame, the improvement is that the base includes a bottom surface and extends upward from the periphery of the bottom surface A plurality of vanes are connected between the outer frame and the side wall of the base, and an outer diameter of the side wall gradually decreases toward the air outlet along the air inlet. The heat dissipation fan of claim 6, wherein the side wall of the base is a truncated cone shape, a conical shape, a streamline shape, an arc shape, or a quadratic curve shape. The heat dissipation fan of claim 6, wherein the side wall of the base has a tapered curved shape near one end of the air outlet, and a cylindrical shape near one end of the air inlet. The heat dissipation fan according to any one of claims 6 to 8, wherein each of the vanes includes a proximal end and a distal end, the proximal end being connected to the side wall of the base, the distal end and the frame The inner walls are connected, and the height of each vane changes radially, and the height of the vane at the proximal end is smaller than the height of the distal end. The heat dissipation fan of claim 9, wherein the distal end of each vane is flush with the bottom surface of the base, and the lower end of each vane and the base side of the base is higher than the bottom surface of the base.