TW201934880A - Impeller of a centrifugal fan - Google Patents

Abstract

An impeller of a centrifugal fan is provided to overcome the difficulty in reducing the noise of the impeller of the conventional centrifugal fan. The impeller includes a shaft, a hub connected to the shaft, an extension plate connected to the hub, a plurality of blades coupled with the outer periphery of the hub, and an air-guiding cover connected to top edges of the blades. Each of the blades has a bottom edge connected to the extension plate. The hub includes an annular wall spaced from inner and outer edges of each of the blades at first and second radial gaps, respectively. A ratio of the second radial gap to the first radial gap is 2.9-3.9.

Description

Centrifugal fan wheel

The invention relates to a fan wheel of a centrifugal fan, in particular to a fan wheel of a centrifugal fan which can be applied to systems such as air conditioners or ventilation equipment.

Please refer to FIGS. 1 and 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 pillar 911. The fan wheel 92 has a rotating shaft 921 connected to a hub 922. The rotating shaft 921 is rotatably provided on the center pillar 911. Several fan blades 923 are connected to the outer surface of the hub 922 by one end, and the stator group 93 is provided on the shaft. The periphery of the center column 911. The conventional centrifugal fan 9 can directly assemble and position the base 91 in a system such as an air conditioner or a ventilation device, so as to drive the airflow by the rotation of the fan wheel 92. Several embodiments similar to the conventional centrifugal fan 9 have been disclosed in the patent cases of Republic of China Publication No. 200838396, Publication No. I530777, and No. I529309.

However, since there is no structure for guiding the airflow above the plurality of fan blades 923 of the conventional centrifugal fan 9, the airflow entering the space between the plurality of fan blades 923 will be relatively disordered, so that it is difficult to reduce the operating noise. In addition, it was found through experiments that not only the problem of turbulent airflow, but also the shape and size ratio of other components in the fan wheel 92 except the rotating shaft 921 will also affect the operating noise to varying degrees.

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

In order to solve the above problems, an object of the present invention is to provide a fan wheel of a centrifugal fan, It can improve the smoothness of the airflow, thereby effectively reducing the operating noise without reducing the air volume.

The following directional or similar terms of the present invention, such as "front", "rear", "up (top)", "down (bottom)", "inside", "outside", "side", etc. With reference to the directions of the accompanying drawings, each directivity or its approximate terms are only used to assist in explaining and understanding the embodiments of the present invention, and are not intended to limit the present invention.

The fan wheel of the centrifugal fan of the present invention comprises: a rotating shaft; a hub connected to the rotating shaft; an extension disk connected to the hub; a plurality of fan blades, and the plurality of fan rings are arranged on the hub. At the outer periphery, the bottom edges of the fan blades are connected to the extension disk; and a wind guide cover is connected to the top edges of the fan blades; wherein the hub has an annular wall, and the annular wall of the hub and each The inner edge of the fan blade has a first radial distance, the ring wall of the hub and the outer edge of each fan blade have a second radial distance, and the ratio of the second radial distance to the first radial distance It is 2.9 ~ 3.9.

According to this, the fan wheel of the centrifugal fan of the present invention can improve the smoothness of the guiding airflow when the fan wheel of the centrifugal fan is in operation by providing a wind guide cover and maintaining other types and size ratios of the components other than the rotating shaft. Therefore, not only the air volume is not reduced due to the installation of the air guide cover, but also the smoothness of the air flow is improved to effectively reduce the operating noise and other effects.

The top edge of each fan blade has a highest point, and the highest point of each fan blade is lower than the top edge of the hub. In this way, it has the effects of improving the smoothness of the air flow.

Wherein, the wind deflector has an air inlet, and the hub and the highest point of each fan blade are located in the air inlet. In this way, it has the effects of improving the smoothness of the air flow.

The inner surface of the air deflector has an axially extending portion, and the axially extending portion forms the air inlet. In this way, it has the effects of improving the smoothness of the air flow.

The highest point of each fan blade is located at the junction of the top edge and the inner edge, and the inner edge of each fan blade extends in an arc shape toward the hub to the extension disk. In this way, it has the effects of improving the smoothness of the air flow.

Wherein, the inner edge of each of the blades has an innermost point connected to the extension disc and connected to the wheel. The hubs are spaced apart, and the first radial distance is formed between the ring wall of the hub and the innermost point of each of the blades. In this way, it has the effects of improving the smoothness of the air flow.

The bottom edge of the fan blades extends to the outer edge of the extension plate, and the top edge of the fan blades extends to the outer edge of the air guide cover. The outer edge of the air guide cover and the outer edge of the extension plate Several air outlets are separated between the edges by the fan blades. In this way, it has the effects of improving the structural stability of the fan blades and the smoothness of guiding the air flow.

Wherein, a radially extending portion is formed adjacent to the air outlets on the inner surface of the air guide cover and the extension plate. In this way, it has the effects of improving the smoothness of the air flow.

Wherein, a convex portion is formed on the inner surface of the extension disc to connect the radial extension portion and the hub, and the portion where the convex portion connects to the hub is closer to the top of the hub than the portion where the convex portion connects to the radial extension. edge. In this way, it has the effects of improving the smoothness of the air flow.

Among them, the distance between any two adjacent blades increases from the inner edge to the outer edge. In this way, it has the effects of improving the smoothness of the air flow.

Wherein, a part of each fan blade top edge that is not connected by the air deflector cover forms a deflector, and the deflector is inclined from the center to two sides. In this way, it has the effects of improving the smoothness of the air flow.

〔this invention〕

1‧‧‧ shaft

2‧‧‧ Wheel

21‧‧‧ Shaft projection

22‧‧‧ ring wall

23‧‧‧ top margin

3‧‧‧ extension tray

31‧‧‧ radial extension

32‧‧‧ raised

4‧‧‧ fan leaves

4a‧‧‧ bottom edge

4b‧‧‧ top margin

4c‧‧‧Inner edge

4d‧‧‧ outer edge

41‧‧‧ highest point

42‧‧‧ innermost point

43‧‧‧Diversion Department

5‧‧‧ air guide cover

51‧‧‧air inlet

52‧‧‧ axial extension

53‧‧‧outlet

54‧‧‧Radial extension

D1‧‧‧First radial distance

D2‧‧‧Second radial distance

〔Usually〕

9‧‧‧ centrifugal fan

91‧‧‧ base

911‧‧‧center

92‧‧‧Fan wheels

921‧‧‧Shaft

922‧‧‧ Wheel

923‧‧‧fan blade

93‧‧‧Stator set

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

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

FIG. 3 is a three-dimensional structure diagram of an embodiment of the present invention.

FIG. 4 is a top structural view of an embodiment of the present invention.

Fig. 5: A sectional structural view taken along the line A-A in Fig. 4.

Fig. 6: A sectional structural view taken along the line B-B of Fig. 4.

In order to make the above and other objects, features, and advantages of the present invention more comprehensible, the following describes the preferred embodiments of the present invention in detail with the accompanying drawings, as follows: Please refer to FIGS. 3 and 5, It is a preferred embodiment of the fan wheel of the centrifugal fan according to the present invention. The fan wheel of the centrifugal fan generally includes a rotating shaft 1, a hub 2, an extension plate 3, a plurality of fan blades 4, and an air guide cover 5. The hub 2 is connected to the rotating shaft 1, the extension disk 3 is connected to the hub 2, and the plurality of fan blades 4 are connected to the extension disk 3 and the wind deflector 5.

The rotating shaft 1 is used to be assembled into a shaft tube (not shown) of a centrifugal fan motor, and drives the entire fan wheel to rotate.

The present invention does not limit the connection structure and manner of the hub 2 and the rotating shaft 1. For example, a hub 2 made of plastic can be used to directly shoot and cover the shaft 1; or a hub 2 made of metal can be used to fit the shaft 1 tightly or by laser welding. The effect that the hub 2 is firmly combined with the rotating shaft 1. In this embodiment, the hub 2 may be provided with a shaft-connecting convex portion 21, and the shaft-connecting convex portion 21 is attached to the rotating shaft 1 to increase the contact area between the hub 2 and the rotating shaft 1, thereby strengthening the hub. The combination of 2 and the rotating shaft 1 is stable. In addition, the hub 2 has an annular wall 22 extending along the axial direction of the rotating shaft 1.

The extension plate 3 is connected to the hub 2 and extends outward. The inner surface of the extension plate 3 (closer to the surface of the air guide cover 5) can be used to connect the fan blades 4; in this embodiment, the extension plate A radially extending portion 31 and a protruding portion 32 may be formed on the inner surface of 3. The radially extending portion 31 extends along the radial direction of the rotating shaft 1 and abuts the outer edge of the extension plate 3. The protruding portion 32 is The portion where the radial extension 31 is connected to the hub 2 is connected to the hub 2, and the portion where the projection 32 is connected to the hub 2 is closer to the top edge 23 of the hub 2 than the portion where the projection 32 is connected to the radial extension 31.

Referring to FIGS. 3, 4, and 6, the plurality of fan blades 4 are arranged on the outer periphery of the hub 2, and the bottom edge 4a of the plurality of fan blades 4 is connected to the inner surface of the extension plate 3. The partial top edge 4b of 4 can be used for connecting the air guide cover 5. In detail, please refer to FIGS. 5 and 6, the top edge 4 b of each fan blade 4 has a highest point 41, and the highest point 41 of each fan blade 4 is lower than the top edge of the hub 2. twenty three. The inner edge 4c of each of the blades 4 is adjacent to the hub 2 and the outer edge 4d is far from the hub 2. The highest point 41 of each of the blades 4 is located at the junction of the top edge 4b and the inner edge 4c. The edge 4c preferably extends in an arc shape toward the hub 2 to the extension disc 3, so the inner edge 4c of each blade 4 has an innermost point 42 connected to the extension disc 3 and spaced from the hub 2. A guide portion 43 may be formed at a portion of the top edge 4b of each of the fan blades 4 that is not connected to the air guide cover 5, and the guide portion 43 is inclined from the center to two sides.

Among them, please refer to FIG. 4. The ring wall 22 of the hub 2 and the inner edge 4 c of each of the blades 4 (the innermost point 42 in this embodiment) have a first radial distance D1. The annular wall 22 of 2 and the outer edge 4d of each of the fan blades 4 have a second radial distance D2, and the ratio (D2 / D1) of the second radial distance D2 to the first radial distance D1 is preferably 2.9. ~ 3.9. In addition, the distance between any two adjacent blades 4 can be increased from the inner edge 4c to the outer edge 4d.

Please refer to FIGS. 3 and 5, the air guide cover 5 is connected to the top edge 4 b of the fan blades 4 near the outer edge 4 d. The air guide cover 5 has an air inlet 51, the hub 2 and each The highest points 41 of the fan blades 4 are all located in the air inlet 51. The inner surface of the air baffle 5 (closer to the surface of the extension plate 3) has an axially extending portion 52 that extends upward along the axial direction of the rotating shaft 1 and the axially extending portion 52 The free end edge of the air inlet 51 forms the air inlet 51.

Please refer to FIGS. 3 and 6. In this embodiment, the bottom edges 4 a of the fan blades 4 preferably extend to the outer edge of the extension plate 3, and the top edges 4 b of the fan blades 4 also preferably extend. To the outer edge of the air guide cover 5; thus, the outer edges of the air guide cover 5 and the outer edge of the extension plate 3 may be separated by the fan blades 4 to form a plurality of air outlets 53. In addition, a radial extension 54 may be formed on the inner surface of the air guide cover 5. The radial extension 54 extends along the radial direction of the rotating shaft 1 and abuts the outer edge of the air guide cover 5. Therefore, the air guide cover 5 The radially extending portion 54 of 5 may be opposite to the radially extending portion 31 of the extension plate 3, and the air guide cover 5 and the radially extending portions 54 and 31 of the extension plate 3 are adjacent to the air outlets 53.

Please refer to Figs. 3 and 5, according to the foregoing structure, the fan wheel of the centrifugal fan of the present invention After being assembled to a fan wheel seat located in a system housing such as an air conditioner or a ventilator, the fan wheel can be used to drive the airflow, so that the airflow passes through the air inlet 51 of the air guide cover 5 and is subject to the air guide. The axially extending portion 52 of the cover 5 guides and flows forward to the top edge 4b of each of the blades 4, and then the airflow guide 43 of the top edge 4b of each of the blades 4 divides the airflow from the center to the two sides so that The airflow can smoothly enter between any two adjacent blades 4 and flow to the air outlets 53 along the convex portion 32 of the extension plate 3; before exiting the fan wheel, it can also pass through the air guide cover. 5 and the radial extensions 54 and 31 of the extension disc 3 guide the airflow to flow along the radial direction of the rotating shaft 1, thereby improving the smoothness of the airflow.

Among them, please refer to FIG. 3 and FIG. 6. Since the inner edge 4c of each of the blades 4 is selected to be an arc-extended shape in this embodiment, the airflow introduced into the air inlet 51 can be delayed to contact each of them. The time of the inner edge 4c of the fan blade 4 without hitting the top edge 4b and the inner edge 4c of each fan blade 4 at once, which is particularly helpful to improve the smoothness of the airflow.

In summary, the fan wheel of the centrifugal fan of the present invention can provide a wind guide cover and enable other components other than the rotating shaft to maintain a specific shape and size ratio, thereby improving the guide airflow when the fan wheel of the centrifugal fan operates. Smoothness, not only will the air volume not be reduced due to the installation of the air deflector cover, but also the smoothness of the air flow will be improved to effectively reduce the operating noise and other effects.

Although the present invention has been disclosed using the above-mentioned preferred embodiments, it is not intended to limit the present invention. Anyone skilled in the art can make various changes and modifications to the above embodiments without departing from the spirit and scope of the present invention. The technical scope protected by the invention, so the scope of protection of the present invention shall be determined by the scope of the appended patent application.

Claims (11)

A fan wheel of a centrifugal fan includes: a rotating shaft; a hub connected to the rotating shaft; an extension disk connected to the hub; a plurality of fan blades, and the fan blade rings are arranged on the outer periphery of the hub, The bottom edges of the fan blades are connected to the extension plate; and a wind cover is connected to the top edges of the fan blades; wherein the hub has a ring wall, and the ring wall of the hub and each fan The inner edge of the blade has a first radial distance, and the ring wall of the hub and the outer edge of each fan blade have a second radial distance. The ratio of the second radial distance to the first radial distance is 2.9. ~ 3.9. The fan wheel of the centrifugal fan according to item 1 of the scope of the patent application, wherein the top edge of each of the blades has a highest point, and the highest point of each of the blades is lower than the top edge of the hub. The fan wheel of the centrifugal fan according to item 2 of the scope of patent application, wherein the air guide cover has an air inlet, and the hub and the highest point of each of the blades are located in the air inlet. The fan wheel of the centrifugal fan according to item 3 of the scope of patent application, wherein the inner surface of the air guide cover has an axial extension, and the axial extension forms the air inlet. The fan wheel of the centrifugal fan according to item 2 of the scope of patent application, wherein the highest point of each fan blade is located at the junction of the top edge and the inner edge, and the inner edge of each fan blade extends in an arc shape toward the hub To the extension plate. The fan wheel of the centrifugal fan according to item 5 of the scope of patent application, wherein the inner edge of each blade has an innermost point connected to the extension disk and spaced from the hub, and the ring wall of the hub and each fan The first radial distance is formed between the innermost points of the leaves. The fan wheel of the centrifugal fan according to item 1 of the patent application scope, wherein the bottom edge of the plurality of fan blades extends to the outer edge of the extension disc, and the top edge of the plurality of fan blades extends to the air guide cover. Outer edge of the Between the outer edge of the wind deflector cover and the outer edge of the extension plate, a plurality of air outlets are separated by the plurality of fan blades. The fan wheel of the centrifugal fan according to item 7 of the scope of the patent application, wherein the air guide cover and the inner surface of the extension disc form a radially extending portion adjacent to the air outlets, respectively. The fan wheel of the centrifugal fan according to item 8 of the scope of patent application, wherein the inner surface of the extension plate forms a convex portion connecting the radial extension portion and the hub, and the convex portion is connected to the hub at a position more than that. A portion where the protrusion is connected to the radially extending portion is adjacent to a top edge of the hub. The fan wheel of the centrifugal fan according to item 1 of the scope of patent application, wherein the distance between any two adjacent fan blades increases from the inner edge to the outer edge. The fan wheel of the centrifugal fan according to item 1 of the scope of patent application, wherein a portion of the top edge of each of the blades which is not connected by the air deflector cover forms a deflection portion, and the deflection portion is inclined from the center to two sides Type.