TWI681127B - Centrifugal fan and impeller thereof - Google Patents

Abstract

A centrifugal fan and an impeller thereof are provided to overcome the difficulty in reducing the noise of the conventional centrifugal fan. The centrifugal fan according to the invention includes a base having a shaft tube, a stator unit mounted around the shaft tube, and an impeller having a shaft connected to a hub. The shaft is rotatably received in the shaft tube. A plurality of blades is mounted on an outer periphery of the hub. Each of the blade includes a highest top face higher than a top face of the hub. The outer edges of the blades define a maximal outer diameter. A ratio of an outer diameter of the hub to the maximal outer diameter is larger than 0.4, or is equal to or smaller than 0.5.

Description

Centrifugal fan and its fan wheel

The invention relates to a centrifugal fan and its fan wheel, in particular to a centrifugal fan and its fan wheel that can be directly assembled in a system such as a freezer or refrigerator without a frame.

Please refer to FIG. 1 and FIG. 2, which is a conventional centrifugal fan 9, the conventional centrifugal fan 9 has a base 91, a fan 92 and a certain sub-group 93, the base 91 has a center column 911 The fan wheel 92 has a rotating shaft 921 connected to a hub 922, the rotating shaft 921 is rotatably disposed on the center pillar 911, a plurality of fan blades 923 are respectively connected to the outer surface of the hub 922 from one end, and the stator group 93 is disposed on the The outer periphery of the center pillar 911. The conventional centrifugal fan 9 can directly assemble and position the base 91 in a system such as a freezer or a refrigerator, so that the rotation of the fan wheel 92 can drive the air flow into the system from the air inlet opened on the system casing Inside, it is discharged to the outside from the air outlet opened on the system casing. Several embodiments similar to the conventional centrifugal fan 9 have been disclosed in the patent cases published by Republic of China No. 200838396, Announcements No. I530777 and No. I529309.

However, since the top edge of each blade 923 of the conventional centrifugal fan 9 is the same height as or lower than the top edge of the hub 922, the airflow enters the rotation range of the fan 92 First, it will rush towards the top edge of the hub 922 before it is disturbed by the several blades 923 and flows to the side end; accordingly, the operation noise of the conventional centrifugal fan 9 has always had a bottleneck that is difficult to reduce. In addition, it has been found through experiments that not only is the problem of airflow rushing toward the top edge of the hub 922, but also the shape and size ratio of the other components of the fan 92 except the rotating shaft 921, which will also affect the operating noise to varying degrees.

In view of this, the conventional centrifugal fan does still need to be improved.

In order to solve the above problems, the object of the present invention is to provide a centrifugal fan and its fan wheel, which can improve the smoothness of the air flow and reduce the operation noise.

The following directivity or similar terms of the present invention, such as "front", "rear", "upper (top)", "lower (bottom)", "inner", "outer", "side", etc., mainly With reference to the directions of the attached drawings, each directivity or its approximate terms are only used to help explain and understand the embodiments of the present invention, and are not intended to limit the present invention.

The centrifugal fan of the present invention includes: a base with a shaft tube; a certain subgroup, the stator group is disposed on the outer periphery of the shaft tube; and a fan wheel with a rotating shaft and a connecting ring, The rotating shaft is connected with a hub, the rotating shaft is rotatably provided on the shaft tube, a plurality of fan blade rings are provided on the outer periphery of the hub, the connecting ring is connected with the several fan blades, the connecting ring has a plurality of ribs to form a plurality of Counterweight groove; wherein, each of the blades has a highest top edge, each of the highest top edges is higher than the top edge of the hub; the outer edges of the several blades form a maximum outer diameter, the outer diameter of the hub and the The ratio of the maximum outer diameter is greater than 0.4 and less than or equal to 0.5.

According to this, the centrifugal fan of the present invention can improve the centrifuge by making the highest top edge of each blade higher than the top edge of the hub and maintaining the specific shape and size ratio of other components in the fan wheel except the rotating shaft When the fan is in operation, the smoothness of the air flow is guided, which effectively reduces the operating noise.

Wherein, the hub has an axial extension, and the outer diameter of the hub is the outer diameter of the axial extension. In this way, the structure of the hub is simple and easy to manufacture and assemble, which has the effects of reducing manufacturing costs and improving assembly convenience.

Wherein, in the axial direction of the rotating shaft, the top edge of the hub is separated from the highest top edge of each blade by an axial distance, each blade has a maximum axial height, and the axial distance is not greater than the maximum axial Half of the height. In this way, it can have better guided air flow and reduce operating noise Sound effects.

Wherein, the fan wheel has an extension disk, the extension disk is connected to the hub and extends outward in the radial direction of the rotating shaft, the bottom edges of the blades are connected to the extension disk, and the connecting ring is spaced from the extension disk. In this way, it has the effect of stabilizing the several fan blades.

Wherein, in the radial direction of the rotating shaft, the maximum outer diameter of the blades is less than or equal to the outer diameter of the connecting ring. In this way, the outer edge of each fan blade does not protrude from the connecting ring, which has the effect of preventing the connecting ring from affecting the wind guiding effect of each fan blade.

Wherein, the several fan blades and the connecting ring are integrally formed and connected, and the inner diameter of the connecting ring is greater than or equal to the outer diameter of the bottom edges of the several fan blades. In this way, it has the functions of enhancing manufacturing convenience and ensuring that the finished product can be smoothly released from the mold.

Wherein, the inner circumferential surface of the connecting ring is connected to the outer edges of the several blades. In this way, it can be ensured that the setting of the connecting ring does not affect the air intake.

Wherein, the base has a base plate, and the shaft tube is provided on the base plate. The base plate has an upper surface and a lower surface opposite to each other. The base plate is closed within the range corresponding to the fan wheel, so that the upper surface is The lower surface is not connected. In this way, unnecessary air loss and turbulence phenomena can be reduced, which has the effects of improving the smoothness of the air flow and reducing operating noise.

Wherein, the base has a base plate, the shaft tube is provided on the base plate, the base is provided with a plurality of lugs on the periphery of the base plate, each lug is provided with a positioning hole, and each lug is combined with an elastic pad, the The elastic pad covers the upper and lower surfaces of the lug and does not completely cover the positioning hole. In this way, the base can be assembled and positioned at a predetermined position in the system housing by using a fastener, and the elastic pad can be attached to the system housing to absorb vibration and improve vibration noise.

The invention also provides a fan wheel of a centrifugal fan, comprising: a rotating shaft; a hub connected to the rotating shaft; a plurality of fan blades, the plurality of fan blade rings are provided on the outer periphery of the hub; and a connecting ring, the connection The ring connects the blades, and the connecting ring has a plurality of ribs to form a plurality of weight grooves; wherein each blade has a highest top edge, and each of the highest top edges is higher than the top edge of the hub; The outer edges of the blades form a maximum outer diameter, and the ratio of the outer diameter of the hub to the maximum outer diameter is greater than 0.4 and less than or equal to 0.5. In this way, it has the effect of reducing operating noise.

Wherein, the hub has an axial extension, and the outer diameter of the hub is the outer diameter of the axial extension. In this way, the structure of the hub is simple and easy to manufacture and assemble, which has the effects of reducing manufacturing costs and improving assembly convenience.

Wherein, in the axial direction of the rotating shaft, the top edge of the hub is separated from the highest top edge of each blade by an axial distance, each blade has a maximum axial height, and the axial distance is not greater than the maximum axial Half of the height. In this way, it can have better effects of guiding airflow and reducing operation noise.

Wherein, the fan wheel has an extension disk, the extension disk is connected to the hub and extends outward in the radial direction of the rotating shaft, the bottom edges of the blades are connected to the extension disk, and the connecting ring is spaced from the extension disk. In this way, it has the effect of stabilizing the several fan blades.

Wherein, in the radial direction of the rotating shaft, the maximum outer diameter of the blades is less than or equal to the outer diameter of the connecting ring. In this way, the outer edge of each fan blade does not protrude from the connecting ring, which has the effect of preventing the connecting ring from affecting the wind guiding effect of each fan blade.

Wherein, the several fan blades and the connecting ring are integrally formed and connected, and the inner diameter of the connecting ring is greater than or equal to the outer diameter of the bottom edges of the several fan blades. In this way, it has the functions of enhancing manufacturing convenience and ensuring that the finished product can be smoothly released from the mold.

Wherein, the inner circumferential surface of the connecting ring is connected to the outer edges of the several blades. In this way, it can be ensured that the setting of the connecting ring does not affect the air intake.

〔this invention〕

1‧‧‧Dock

11‧‧‧ substrate

11a‧‧‧Upper surface

11b‧‧‧Lower surface

12‧‧‧Shaft tube

13‧‧‧ lug

131‧‧‧Locating hole

2‧‧‧Stator

21‧‧‧Iron core

22‧‧‧coil set

3‧‧‧fan wheel

31‧‧‧spindle

32‧‧‧Wheel

321‧‧‧Axial extension

33‧‧‧ fan blade

331‧‧‧Highest top edge

332‧‧‧Outer edge

333‧‧‧Bottom edge

34‧‧‧Magnetic parts

35‧‧‧Extended plate

36‧‧‧Connecting ring

361‧‧‧Inner peripheral surface

362‧‧‧ Counterweight slot

4‧‧‧Elastic pad

D1‧‧‧Maximum outer diameter

d1‧‧‧Outer diameter

D2‧‧‧Outer diameter

d2‧‧‧Inner diameter

D3‧‧‧Outer diameter

H‧‧‧Maximum axial height

h‧‧‧Axial spacing

〔Convention〕

9‧‧‧Centrifugal fan

91‧‧‧Dock

911‧‧‧Central column

92‧‧‧fan wheel

921‧‧‧spindle

922‧‧‧Wheel

923‧‧‧fan blade

93‧‧‧Stator

Figure 1: Schematic diagram of a three-dimensional structure of a conventional centrifugal fan.

Fig. 2: A schematic sectional view of a conventional centrifugal fan.

Figure 3: Schematic diagram of a three-dimensional structure of an embodiment of the centrifugal fan of the present invention.

Fig. 4: A schematic sectional view of an embodiment of a centrifugal fan of the present invention.

Fig. 5: A schematic view of a three-dimensional structure of an embodiment of a fan wheel of the present invention.

In order to make the above and other objects, features and advantages of the present invention more obvious and understandable, the preferred embodiments of the present invention are described below in conjunction with the attached drawings, which are described in detail as follows: Please refer to Figures 3 and 4. It is a preferred embodiment of the centrifugal fan of the present invention. The centrifugal fan generally includes a base 1, a certain sub-group 2 and a fan wheel 3, the stator group 2 and the fan wheel 3 are assembled on the base 1 .

The base 1 has a base plate 11 and an axis tube 12. The axis tube 12 can be combined with the base plate 11, or preferably, the axis tube 12 and the base plate 11 are integrally formed and connected, thereby simplifying the structural complexity of the base 1 . In addition, one end of the shaft tube 12 is open, and the other end is preferably closed to prevent leakage of the lubricating fluid injected into the shaft tube 12 from the bottom of the shaft tube 12.

In addition, the base 1 may be provided with a plurality of lugs 13 on the periphery of the base plate 11, each lug 13 is provided with a positioning hole 131, and each lug 13 is combined with an elastic pad 4 (such as a rubber pad). The pad 4 covers the upper and lower surfaces of the lug 13, but maintains that the positioning hole 131 is not completely covered. In this way, a locking member (such as a screw, not shown) can be passed through each positioning hole 131 to assemble and position the base 1 at a predetermined position in a system casing (not shown) such as a freezer or refrigerator , And the elastic pad 4 is attached to the system casing to absorb vibration, so that the vibration generated by the centrifugal fan of the present invention is not easily transmitted to the system casing, and the vibration generated during the system operation is not easily transmitted to the base 1 , So it can effectively improve the vibration noise problem.

The stator group 2 is disposed on the outer periphery of the shaft tube 12, and the stator group 2 can be of various structural designs that can drive the fan wheel 3 to rotate; for example, but not limited to, in this embodiment, the stator group 2 can be combined and nested On the outer peripheral wall of the shaft tube 12, the stator assembly 2 includes an iron core 21 and a coil assembly 22 wound around the iron core 21.

Please refer to Figures 4 and 5, the fan wheel 3 has a rotating shaft 31, a hub 32, a number of A fan blade 33 and a magnetic member 34, the rotating shaft 31 is rotatably disposed on the shaft tube 12, the hub 32 is connected to the rotating shaft 31, the plurality of fan blades 33 are disposed around the outer periphery of the hub 32, the magnetic member 34 It is arranged on the inner surface of the hub 32 and is opposed to the iron core 21 of the stator group 2; thereby, the stator group 2 can drive the fan wheel 3 to rotate after being energized to generate a magnetic field. The substrate 11 of the base 1 has an upper surface 11a and a lower surface 11b opposite to each other. The substrate 11 preferably has a closed shape in a range corresponding to the axial direction of the fan wheel 3, so that the upper surface 11a and the lower surface 11b is not connected to reduce unnecessary air loss and turbulence, ensure that the air flow can be smoothly guided to the side, and have the function of reducing operating noise.

More specifically, each fan blade 33 has a highest top edge 331, and the highest top edge 331 of each fan blade 33 is higher than the top edge of the hub 32, so that the airflow enters the rotation range of the fan wheel 3, Before rushing to the top edge of the hub 32, it can be disturbed by the plurality of blades 33 and flow to the side end, thereby improving the smoothness of the guided air flow and reducing the operating noise. Specifically, in the axial direction of the rotating shaft 31, the top edge of the hub 32 is separated from the highest top edge 331 of each blade 33 by an axial distance h, and each blade 33 has a maximum axial height H, The axial distance h is preferably not greater than one-half of the maximum axial height H, so as to achieve better effects of guiding air flow and reducing operating noise.

In addition, the outer edges 332 of the blades 33 form a maximum outer diameter D1. The ratio of the outer diameter D2 of the hub 32 to the maximum outer diameter D1 (D2/D1) is preferably greater than 0.4 and less than or equal to 0.5. To achieve the most obvious effect of reducing operating noise. The hub 32 has an axial extension 321, and the outer diameter D2 of the hub 32 is the outer diameter of the axial extension 321.

The fan wheel 3 of this embodiment further has an extension disk 35 and a connecting ring 36. The extension disk 35 is connected to the hub 32 and extends outward in the radial direction of the rotating shaft 31. The bottom edges 333 of the blades 33 are connected The extension disk 35; the connecting ring 36 connects the plurality of blades 33 and is spaced apart from the extension disk 35 to stabilize the plurality of blades 33. Wherein, in the radial direction of the rotating shaft 31, the maximum outer diameter D1 of the blades 33 is preferably less than or equal to the outer diameter d1 of the connecting ring 36, so that The outer edge 332 of each fan blade 33 does not protrude from the connecting ring 36, so as to prevent the arrangement of the connecting ring 36 from affecting the wind guiding effect of each fan blade 33. Therefore, the outer edge 332 of each fan blade 33 may be straight as shown in the figure, or inclined toward the hub 32 from top to bottom, etc. The present invention is not limited. In particular, when selecting to integrally connect the plurality of blades 33 and the connecting ring 36 to improve manufacturing convenience, it is preferable to make the inner diameter d2 of the connecting ring 36 greater than or equal to the bottom edges of the plurality of blades 33 The outer diameter D3 of 333 ensures that the finished product after injection molding can be smoothly released from the mold.

In addition, the inner circumferential surface 361 of the connecting ring 36 is preferably connected to the outer edges 332 of the plurality of blades 33, so as to ensure that the arrangement of the connecting ring 36 does not affect the air intake, and the connecting ring 36 connects each of the blades 33 places are preferably set to arc-guiding type, in order to strengthen the strength of the joint, and can avoid the place easy to crack. The connecting ring 36 can also be provided with at least one weight groove 362, which can be used to accommodate a balance weight, thereby adjusting the weight of the fan wheel 3, thereby improving the smoothness of rotation of the fan wheel 3 and Smoothness.

In summary, the centrifugal fan and the fan wheel of the present invention can maintain the specific shape and size of the other components of the fan wheel except the rotating shaft by making the highest top edge of each blade higher than the top edge of the hub Proportion, so as to improve the smoothness of the air flow during the operation of the centrifugal fan, and effectively reduce the operating noise.

Although the present invention has been disclosed using the above-mentioned preferred embodiments, it is not intended to limit the present invention. Anyone who is familiar with this art without departing from the spirit and scope of the present invention still makes various changes and modifications to the above-mentioned embodiments. The technical scope of the invention is protected, so the scope of protection of the present invention shall be subject to the scope defined in the appended patent application.

1‧‧‧Dock

11‧‧‧ substrate

11a‧‧‧Upper surface

11b‧‧‧Lower surface

12‧‧‧Shaft tube

2‧‧‧Stator

21‧‧‧Iron core

22‧‧‧coil set

3‧‧‧fan wheel

31‧‧‧spindle

32‧‧‧Wheel

321‧‧‧Axial extension

33‧‧‧ fan blade

331‧‧‧Highest top edge

332‧‧‧Outer edge

333‧‧‧Bottom edge

34‧‧‧Magnetic parts

35‧‧‧Extended plate

36‧‧‧Connecting ring

361‧‧‧Inner peripheral surface

362‧‧‧ Counterweight slot

D1‧‧‧Maximum outer diameter

d1‧‧‧Outer diameter

D2‧‧‧Outer diameter

d2‧‧‧Inner diameter

D3‧‧‧Outer diameter

H‧‧‧Maximum axial height

h‧‧‧Axial spacing

Claims (16)

A centrifugal fan includes: a base with a shaft tube; a certain subgroup, the stator group is disposed on the outer periphery of the shaft tube; and a fan wheel with a rotating shaft and a connecting ring, the rotating shaft A hub is connected, the rotating shaft is rotatably provided on the shaft tube, a plurality of fan blade rings are provided on the outer periphery of the hub, the connecting ring is connected with the several fan blades, the connecting ring has a plurality of ribs to form a plurality of counterweights Groove; wherein, each of the blades has a highest top edge, each of the highest top edges is higher than the top edge of the hub; the outer edges of the several blades form a maximum outer diameter, the outer diameter of the hub and the maximum outer diameter The diameter ratio is greater than 0.4 and less than or equal to 0.5. The centrifugal fan according to item 1 of the patent application scope, wherein the hub has an axial extension, and the outer diameter of the hub is the outer diameter of the axial extension. The centrifugal fan according to item 1 of the patent application scope, wherein, in the axial direction of the rotating shaft, the top edge of the hub is separated from the highest top edge of each blade by an axial distance, and each blade has a maximum axis To the height, the axial distance is not greater than half of the maximum axial height. The centrifugal fan according to item 1 of the patent application scope, wherein the fan wheel has an extension disk, the extension disk is connected to the hub and extends outward in the radial direction of the rotating shaft, and the bottom edges of the blades are connected to the An extension disk, the connecting ring is spaced from the extension disk. The centrifugal fan according to item 4 of the patent application scope, wherein, in the radial direction of the rotating shaft, the maximum outer diameter of the blades is less than or equal to the outer diameter of the connecting ring. The centrifugal fan according to item 5 of the patent application scope, wherein the blades and the connecting ring are integrally connected to each other, and the inner diameter of the connecting ring is greater than or equal to the outer diameter of the bottom edges of the blades. The centrifugal fan as described in item 5 of the patent application scope, wherein the inner circumferential surface of the connecting ring is connected to the outer edges of the several blades. The centrifugal fan as described in item 1 of the patent application, wherein the base has a base plate, the shaft The tube is arranged on the base plate, and the base plate has an upper surface and a lower surface opposite to each other. The base plate is closed in a range corresponding to the axial direction of the fan wheel, so that the upper surface and the lower surface are not connected. The centrifugal fan according to item 1 of the patent application scope, wherein the base has a base plate, the shaft tube is provided on the base plate, the base is provided with a plurality of lugs on the periphery of the base plate, and each lug is provided with a For the positioning hole, each lug is combined with an elastic pad, and the elastic pad covers the upper and lower surfaces of the lug and does not completely cover the positioning hole. A fan wheel of a centrifugal fan includes: a rotating shaft; a hub connected to the rotating shaft; a plurality of fan blades, the plurality of fan blade rings are provided on the outer periphery of the hub; and a connecting ring, the connecting ring is connected to the number Blades, the connecting ring has several ribs to form several weight grooves; wherein each blade has a highest top edge, each of the highest top edges is higher than the top edge of the hub; the number of blades The outer edge forms a maximum outer diameter, and the ratio of the outer diameter of the hub to the maximum outer diameter is greater than 0.4 and less than or equal to 0.5. The fan wheel of a centrifugal fan as described in item 10 of the patent application range, wherein the hub has an axial extension, and the outer diameter of the hub is the outer diameter of the axial extension. The fan wheel of a centrifugal fan as described in item 10 of the patent application scope, wherein, in the axial direction of the rotating shaft, the top edge of the hub is spaced an axial distance from the highest top edge of each fan blade, and each fan blade has A maximum axial height, the axial distance is not greater than half of the maximum axial height. The fan wheel of a centrifugal fan as described in item 10 of the patent application range, wherein the fan wheel has an extension disc connected to the hub and extending outward in the radial direction of the rotating shaft, the bottom of the plurality of blades The rim is connected to the extension disk, and the connection ring is spaced from the extension disk. The fan wheel of the centrifugal fan as described in item 13 of the patent application range, wherein, in the radial direction of the rotating shaft, the maximum outer diameter of the blades is less than or equal to the outer diameter of the connecting ring. The fan wheel of the centrifugal fan as described in item 14 of the patent application scope, wherein the blades and the connecting ring are integrally formed and connected, and the inner diameter of the connecting ring is greater than or equal to the outer edge of the bottom edges of the blades path. The fan wheel of the centrifugal fan as described in item 14 of the patent application scope, wherein the inner circumferential surface of the connecting ring is connected to the outer edges of the several blades.

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