WO2020077520A1

WO2020077520A1 - Impellers

Info

Publication number: WO2020077520A1
Application number: PCT/CN2018/110387
Authority: WO
Inventors: Ming Wen; Wei Zhao
Original assignee: Hewlett-Packard Development Company, L.P.
Priority date: 2018-10-16
Filing date: 2018-10-16
Publication date: 2020-04-23

Abstract

An impeller (100) comprises a hub element (102), and a plurality of blades (104-1, 104-2, 104-3) coupled to the hub element (102). Each blade of the plurality of blades (104-1, 104-2, 104-3) includes an inner edge (202) abutting the hub element (102), an outer edge (204) away from the inner edge (202), a first curved edge (206) between a first end (210-1) of the inner edge (202) and a first end (212-1) of the outer edge (204), and a second curved edge (208) between a second end (210-2) of the inner edge (202) and a second end (212-2) of the outer edge (204), such that a surface of the blade extending from the first curved edge (206) to the second curved edge (208) has an asymmetric wave-like profile (214).

Description

IMPELLERS

BACKGROUND

Air-flow devices, such as fans, include impellers. An impeller of an air-flow device is rotated, for example, by a motor to blow air in a certain direction. The impeller, when rotated, creates a low-pressure region on one side of the impeller, which results in flow of air across the rotating impeller.

BRIEF DESCRIPTION OF DRAWINGS

The following detailed description references the drawings, wherein:

Fig. 1 illustrates an impeller, according to an example;

Fig. 2 illustrates a schematic of a blade coupled to a hub element of the impeller of Fig. 1; and

Fig. 3 illustrates various dimensions associated with the blade and the hub element of the impeller of Fig. 1;

Fig. 4 illustrates an air-flow device with an impeller, according to an example; and

Fig. 5 illustrates an electronic device with an impeller, according to an example.

DETAILED DESCRIPTION

Air-flow devices may be implemented in electronic devices, such as computers and servers, for the purpose of cooling internal components thereof. An air-flow device, also referred to as a fan, may include an impeller which, when rotated, blows air in a direction from an outer side to an inner side of the electronic device. With the arrangement of the air-flow device, dust particles from outside may settle on blades of the impeller. Over a period of time, a thick layer of dust particles may form on the blades of the impeller, which may adversely affect the performance of the air-flow device with respect to cooling of the internal components of the electronic device.

A mesh-like film may be attached to the outer side of the electronic device, or to the air-flow device, to prevent settling of dust particles on the blades of the impeller. Dust particles may still pass through the openings in the mesh-like film. Over a period of time, dust particles may also accumulate on the mesh-like film itself, which may result in ineffective heat dissipation from the internal components of the electronic device.

The present subject matter relates to impellers, air-flow devices having such impellers, and electronic devices including the air-flow devices having such impellers. The impellers of the present subject matter enable dual direction air-flow across the impellers, depending on the direction of rotation of the impellers. An impeller of the present subject matter, implemented in an air-flow device of an electronic device, can be rotated in one direction to flow air into the electronic device for cooling down the internal components of the electronic device. The impeller can be rotated in the opposite direction to flow air out from the electronic device, which may facilitate blowing away the dust particles that may have settled on the impeller.

In an example, an impeller of an air-flow device includes a hub element and a plurality of blades coupled to the hub element. The hub element may be a part of the impeller through which the impeller is mounted on a shaft of a motor for rotating the impeller. The plurality of blades is a part of the impeller which, when rotated, creates a low-pressure region on one side of the impeller, which results in flow of air across the rotating impeller. In an example, each blade of the plurality of blades of the impeller includes an inner edge abutting the hub element, an outer edge away from the inner edge, a first curved edge between a first end of the inner edge and a first end of the outer edge, and a second curved edge between a second end of the inner edge and a second end of the outer edge. The inner edge, the outer edge, the first curved edge, and the second curved edge are profiled such that a surface of each blade extending from the first curved edge to the second curved edge has an asymmetric wave-like profile. Further, the first curved edge, the second curved edge, and the surface of each blade extending from the inner edge to the outer edge have the same curved profile as each other. In an example, the impeller includes an odd number of blades to annul sympathetic vibrations which may otherwise be experienced by the impeller.

The profile of the blades, as described above, enables the impeller to blow air in both the directions parallel to axis of rotation of the impeller. The direction in which air is blown by the impeller depends on the direction of rotation of the impeller. The impeller of the present subject matter in an air-flow device, installed in an electronic device, can flow air into the electronic device when the impeller is rotated a first direction and can flow air out from the electronic device when the impeller is rotated in a second direction opposite to the first direction. Rotation of the impeller in the first direction to flow air into the electronic device may cool down the internal components of the electronic device. Rotation of the impeller in the second direction to flow air out from the electronic device may facilitate blowing away the dust particles that may have settled on the impeller.

The following detailed description refers to the accompanying drawings. Wherever possible, the same reference numbers are used in the drawings and the following description to refer to the same or similar parts. While several examples are described in the description, modifications, adaptations, and other implementations are possible. Accordingly, the following detailed description does not limit the disclosed examples. Instead, the proper scope of the disclosed examples may be defined by the appended claims.

Fig. 1 illustrates an impeller 100, according to an example. The impeller 100 may be installed in an air-flow device, also referred to as a fan, for flow of air. As shown in Fig. 1, the impeller 100 includes a hub element 102 and a plurality of blades 104-1, 104-2, 104-3, coupled to the hub element 102. The hub element 102 may be an annular-shaped element through which the impeller 100 is mounted on a shaft of a motor for rotating the impeller 100. The hub element 102 may have an opening (not shown in Fig. 1) in the center to receive a shaft of a motor. The opening may be a through-and-though opening extending all the way through the hub element 102. The hub element 102 may also include a locking mechanism (not shown in Fig. 1) to secure the impeller 100 on the shaft of the motor such that the impeller 100 rotates in conjunction with the shaft of the motor without moving axially on the shaft. In an example, the locking mechanism may include a threaded slot and a screw on the outer circumferential surface of the hub element 102. The threaded slot may extend all the way from the outer circumferential surface to the opening in the center of the hub element 102 and may have threads corresponding to the threads on the screw. The screw is passed through the thread slot and tightened to affix the impeller 100 on the shaft of the motor.

Each of the plurality of blades, collectively referred to as 104, has a profile which enables the impeller to blow air in both the directions parallel to an axis of rotation of the impeller 100. The axis of rotation, referenced as line AB in Fig. 1, is an axis about which the impeller 100 is rotated. The direction in which air is blown by the impeller 100 depends on the direction of rotation of the impeller 100. Although the impeller 100 is shown to have three blades 104-1, 104-2, 104-3, the impeller may include more than three blades. In an example, the impeller may include an odd number of blades, for example, three blades, five blades, seven blades, or nine blades, etc., to annul sympathetic vibrations which may otherwise be experienced by the impeller. The profile of a blade of the impeller 100 is described in detail with reference to Fig. 2. Each blade of the impeller 100 may have a same profile as described herein with reference to Fig. 2. The operation of the impeller 100 and the airflow across the impeller 100 are described in detail later in the description.

Fig. 2 illustrates a schematic of a blade 104-1 coupled to the hub element 102 of the impeller 100 of Fig. 1. The blade 104-1 includes an inner edge 202 abutting the hub element 102 and an outer edge 204 opposite to and away from the inner edge 202. The blade 104-1 also includes a first curved edge 206 between a first end 210-1 of the inner edge 202 and a first end 212-1 of the outer edge 204, and a second curved edge 208 between a second end 210-2 of the inner edge 202 and a second end 212-2 of the outer edge 204. The inner edge 202, the outer edge 204, the first curved edge 206, and the second curved edge 208, are profiled such that a surface of the blade 104-1 extending from the first curved edge 206 to the second curved edge 208 has an asymmetric wave-like profile. The asymmetric wave-like profile of the surface extending from the first curved edge 206 to the second curved edge 208 is reference by arrow 214 in Fig. 2. The asymmetric wave-like profile 214 has a single wave, i.e., a wave with one crest and one trough, as shown in Fig. 2. An interface of the crest and the trough of the asymmetric wave-like profile 214 is closer to the first curved edge 206 than the second curved edge 208. The interface of the crest and the trough of the asymmetric wave-like profile 214 is represented by a curved tangent line 216. Various dimensions associated with the profile of the blade 104-1 are described with reference to Fig. 3.

Further, as shown in Fig. 2, the first curved edge 206 has a curved profile same as that of the second curved edge 208. Further, the surface of the blade 104-1 extending from the inner edge 202 to the outer edge 204 has the same curved profile as the curved profile of the first curved edge 206 and the second curved edge 208. The curved profile of the surface extending from the inner edge 202 to the outer edge 204 is reference by arrow 218 in Fig. 2. The curved profile, referenced by arrow 218, is an arc which is a part of a circle of a fixed radius in a range of 39 mm to 41 mm. In an example, the curved profile, referenced by arrow 218, is an arc of a circle of a radius of 40 mm.

Fig. 3 illustrates various dimensions associated with the blade 104-1 and the hub element 102 of the impeller 100 of Fig. 1. The dimensions associated with the blade 104-1 are shown with respect to the profile of the inner edge 202 of the blade 104-1, which abuts the hub element 102.

The hub element 102 may have an axial height H in a range of 39 mm to 41 mm. The hub element 102 may have an outer diameter D in a range of 30 mm to 35 mm. The hub element 102 may have an inner diameter, also referred to as the diameter of the opening in the center of the hub element 102, in a range of 20 mm to 25 mm.

As shown in Fig. 3, the first end 210-1 of the inner edge 202 and the second end 212-1 of the inner edge 202 are circumferentially offset X with respect to each other by a distance in range of 15 mm to 17 mm, and axial offset Y with respect to each other by a distance in range of 37 mm to 39 mm. In other words, the first curved edge 206 and the second curved edge 208 of the blade 104-1 are circumferentially offset with respect to each other by a distance in range of 15 mm to 17 mm, and axially offset with respect to each other by a distance in range of 37 mm to 39 mm.

Further, as shown in Fig. 3, the interface of the crest and the trough of the single wave of the asymmetric wave-like profile of the blade 104-1 is circumferentially offset P with respect to the first end 210-1 of the inner edge 202 by a distance in a range of 3.5 mm to 5.5 mm, and axially offset Q with respect to the first end 210-1 of the inner edge 202 by a distance in a range of 13 mm to 15 mm. In other words, the interface is circumferentially offset with respect to the first curved edge 206 by a distance in a range of 3.5 mm to 5.5 mm, and axially offset with respect to the first curved edge by a distance in a range of 13 mm to 15 mm.

Further, the crest of the single wave of the asymmetric wave-like profile is an arc which is a part of a fixed circle of a radius in a range of 23 mm to 25 mm. Similarly, the trough of the single wave of the asymmetric wave-like profile is an arc which is a part of a fixed circle of a radius in a range of 29 mm to 32 mm.

Returning to Fig. 1, when the impeller 100 is rotated in a clockwise direction as shown by arrow 108, the impeller 100 blows air in a direction as shown by arrow 110. The plurality of blades 104 when rotated in the clockwise direction creates a low-pressure region on an axial side of the impeller 100 which is towards end A of the axis of rotation AB and opposite to end B of the axis of rotation AB. The axial side of the impeller 100 may be a side along the axis of rotation AB and away from the plane of rotation of the impeller 100. The low-pressure region on the axial side towards end A of the axis of rotation AB results in flow of air across the rotating impeller 100 in the direction as shown by arrow 110.

Similarly, when the impeller 100 is rotated in an anti-clockwise direction as shown by arrow 112, the impeller 100 blows air in a direction as shown by arrow 114. The plurality of blades 104 when rotated in the anti-clockwise direction creates a low-pressure region on an axial side of the impeller 100 which is towards end B of the axis of rotation AB and opposite to end A of the axis of rotation AB. The low-pressure region on the axial side towards end B of the axis of rotation AB results in flow of air across the rotating impeller 100 in the direction as shown by arrow 114.

Fig. 4 illustrates an air-flow device 400 with an impeller 402, according to an example. The impeller 402 may be the same as the impeller 100 shown in Fig. 1. The air-flow device 400 may also be referred to as a fan. The air-flow device 400 includes a motor 404 with a shaft 406. In an example, the motor 404 is a DC motor that may be implemented in an electronic device, such as a server, a computer, and the like. The impeller 402, as shown in Fig. 4, includes a hub element 408 coupled to the shaft 406 of the motor 404. The hub element 408 may be the same as the hub element 102 of the impeller 100.

The impeller 402 also includes a plurality of blades 410-1, 410-2, 410-3 coupled to the hub element 408. The plurality of blades 410-1, 410-2, 410-3 may be the same as the plurality of blades 104-1, 104-2, 104-3 of the impeller 100. Each of the plurality of blades, collectively and individually referred to as 410 includes an inner edge abutting the hub element 408 and an outer edge opposite to and away from the inner edge. Each blade 410 also includes a first curved edge between a first end of the inner edge and a first end of the outer edge, and a second curved edge between a second end of the inner edge and a second end of the outer edge. The inner edge, the outer edge, the first curved edge, and the second curved edge of each blade 410 are profiled such that a surface of the blade 410 extending from the first curved edge to the second curved edge has an asymmetric wave-like profile. The asymmetric wave-like profile is similar to that described earlier with reference to Fig. 2. The asymmetric wave-like profile has a single wave, i.e., a wave with one crest and one trough. An interface of the crest and the trough of the asymmetric wave-like profile is closer to the first curved edge of the blade 410 than the second curved edge of the blade 410.

Further, the first curved edge, the second curved edge, and the surface of each blade 410 extending from the inner edge to the outer edge have a same curved profile. The asymmetric wave-like profile is similar to that described earlier with reference to Fig. 2. Various dimensions associated with the profile of the blade 410 are similar to those described earlier with reference to Fig. 3.

When the impeller 402 is rotated in a clockwise direction as shown by arrow 412, the impeller 402 blows air in a direction as shown by arrow 414. Whereas, when the impeller 402 is rotated in an anti-clockwise direction as shown by arrow 416, the impeller 402 blows air in a direction as shown by arrow 418.

Fig. 5 illustrates an electronic device 500 with an impeller 502, according to an example. The impeller 502 may be the same as the impeller 100 shown in Fig. 1. The impeller 502 may be a part of an air-flow device installed in the electronic device 500 for cooling down internal components of the electronic device 500. The electronic device 500 may be a computer or a server, or the like.

The electronic device 500 includes a motor 504 with a shaft 506. In an example, the motor 504 is a DC motor. The impeller 502, as shown in Fig. 5, includes a hub element 508 coupled to the shaft 506 of the motor 504. The hub element 508 may be the same as the hub element 102 of the impeller 100.

The impeller 502 also includes a plurality of blades 510-1, 510-2, 510-3 coupled to the hub element 508. The plurality of blades 510-1, 510-2, 510-3 may be the same as the plurality of blades 104-1, 104-2, 104-3 of the impeller 100. Each of the plurality of blades, collectively and individually referred to as 510 includes an inner edge abutting the hub element 508 and an outer edge opposite to and away from the inner edge. Each blade 510 also includes a first curved edge between a first end of the inner edge and a first end of the outer edge, and a second curved edge between a second end of the inner edge and a second end of the outer edge. The inner edge, the outer edge, the first curved edge, and the second curved edge, of each blade 510 are profiled such that a surface of the blade 510 extending from the first curved edge to the second curved edge has an asymmetric single wave profile with an interface of a crest and a trough being closer to the first curved edge of the blade 510 than the second curved edge of the blade 510. The asymmetric single wave profile is similar to the asymmetric wave-like profile described earlier with reference to Fig. 2.

Further, the first curved edge, the second curved edge, and the surface of each blade 510 extending from the inner edge to the outer edge have a same curved profile. The asymmetric wave-like profile is similar to that described earlier with reference to Fig. 2. Various dimensions associated with the profile of the blade 510 are similar to those described earlier with reference to Fig. 3.

When the impeller 502 is rotated in a clockwise direction as shown by arrow 512, the impeller 502 blows air in a direction as shown by arrow 514. Whereas, when the impeller 502 is rotated in an anti-clockwise direction as shown by arrow 516, the impeller 502 blows air in a direction as shown by arrow 518.

In an example, the motor 504 may be operated to rotate in the anti-clockwise direction, shown by arrow 516, to blow air in the direction, shown by arrow 518, to cool the internal components of the electronic device 500. The motor 504 may be intermittently rotated in the clockwise direction, shown by arrow 512, to blow air in the direction, shown by arrow 514, to blow air out from the electronic device 500, thereby removing the dust particles that may have settled on the blades of the impeller 502 of the electronic device 500.

In an example, to remove the dust particles the impeller 502 may be rotated in the clockwise direction at a speed two times, or three times, or more times faster than the speed of rotation of the impeller 502 in the anti-clockwise direction to cool the internal components. The impeller 502 when rotated in the anti-clockwise direction may deliver a thrust which is 25 %to 35 %of the thrust delivered when the impeller 502 is rotated in the clockwise direction. In an example, in the anti-clockwise direction, the impeller 502 may deliver a thrust of 500 gram-force (gf) to 1200 gf. In the clockwise direction, the impeller 502 may deliver a thrust of 2000 gf to 4000 gf.

Although examples for the present disclosure have been described in language specific to structural features, it is to be understood that the appended claims are not limited to the specific features described herein. Rather, the specific features are disclosed and explained as examples of the present disclosure.

Claims

An impeller of an air-flow device, the impeller comprising:

a hub element; and

a plurality of blades coupled to the hub element, each blade of the plurality of blades including:

an inner edge abutting the hub element;

an outer edge away from the inner edge;

a first curved edge between a first end of the inner edge and a first end of the outer edge; and

a second curved edge between a second end of the inner edge and a second end of the outer edge, such that a surface of the blade extending from the first curved edge to the second curved edge has an asymmetric wave-like profile.
The impeller as claimed in claim 1, wherein the first curved edge, the second curved edge, and the surface of the blade extending from the inner edge to the outer edge have a same curved profile.
The impeller as claimed in claim 1, wherein the asymmetric wave-like profile has a single wave with an interface of a crest and a trough of the single wave being closer to the first curved edge than the second curved edge.
The impeller as claimed in claim 3, wherein the interface of the crest and the trough of the single wave is circumferentially offset with respect to the first curved edge by a distance in a range of 3.5 mm to 5.5 mm.
The impeller as claimed in claim 3, wherein the interface of the crest and the trough of the single wave is axially offset with respect to the first curved edge by a distance in a range of 13 mm to 15 mm.
The impeller as claimed in claim 1, wherein the first curved edge and the second curved edge are circumferentially offset with respect to each other by a distance in range of 15 mm to 17 mm.
The impeller as claimed in claim 1, wherein the plurality of blades includes an odd number of blades.
An air-flow device comprising:

a motor with a shaft; and

an impeller including:

a hub element coupled to the shaft of the motor; and

a plurality of blades coupled to the hub element, each blade of the plurality of blades having:

an inner edge abutting the hub element;

an outer edge away from the inner edge;

a first curved edge between a first end of the inner edge and a second end of the outer edge; and

a second curved edge between a second end of the inner edge and a second end of the outer edge, such that:

a surface of the blade extending from the first curved edge to the second curved edge has an asymmetric wave-like profile; and

the first curved edge, the second curved edge, and the surface of the blade extending from the inner edge to the outer edge have a same curved profile.
The air-flow device as claimed in claim 8, wherein the asymmetric wave-like profile has a single wave with an interface of a crest and a trough of the single wave being closer to the first curved edge than the second curved edge.
The air-flow device as claimed in claim 9, wherein the interface of the crest and the trough of the single wave is circumferentially offset with respect to the first curved edge by a distance in a range of 3.5 mm to 5.5 mm.
The air-flow device as claimed in claim 9, wherein the interface of the crest and the trough of the single wave is axially offset with respect to the first curved edge by a distance in a range of 13 mm to 15 mm.
The air-flow device as claimed in claim 8, wherein the first curved edge and the second curved edge are circumferentially offset with respect to each other by a distance in range of 15 mm to 17 mm.
An electronic device comprising:

a motor with a shaft; and

an impeller including:

a hub element coupled to the shaft of the motor; and

a plurality of blades coupled to the hub element, each blade of the plurality of blades having:

an inner edge abutting the hub element;

an outer edge away from the inner edge;

a first curved edge between a first end of the inner edge and a second end of the outer edge; and

a second curved edge between a second end of the inner edge and a second end of the outer edge, such that a surface of the blade extending from the first curved edge to the second curved edge has an asymmetric single wave profile with an interface of a crest and a trough being closer to the first curved edge than the second curved edge.
The electronic device as claimed in claim 13, wherein the first curved edge, the second curved edge, and the surface of the blade extending from the inner edge to the outer edge have a same curved profile.
The electronic device as claimed in claim 13, wherein the plurality of blades includes an odd number of blades.