FAN

Abstract

A fan impeller includes a hub, a plurality of annular blades, and a plurality of spacers. The annular blades are stacked along an axial direction of the hub and disposed around the outer periphery of the hub. The extension directions of the annular blades are perpendicular to the axial direction of the hub. Each of the spacers is disposed between the two adjacent annular blades. Each of the annular blades has an inner periphery. A gap is provided between the inner periphery and the hub. Each of the annular blades further includes a plurality of spokes and an inner ring, the inner ring is disposed on and connected to the outer periphery of the hub, and two ends of the spoke are connected to the inner periphery and the inner ring of the annular blade. The spacers are separately disposed on the inner rings of the annular blades, respectively.

Description

BACKGROUND OF THE INVENTION

Field of Invention

This disclosure relates to a fan and, in particular, to a fan having annular blades.

Related Art

The current electronic devices will generate a lot of heat in operation as the performance of the electronic devices increases. If the heat cannot be dissipated immediately, the temperature inside the electronic device will increase, which may damage the internal components and decrease the performance and lifetime of the electronic device. A fan is a common heat dissipation device for the electronic devices. However, the conventional fan utilizes the blades to generate airflow by friction, so it may easily accompany the high-frequency noise, which can cause uncomfortable of the users.

Therefore, it is desired to provide a fan with lower high-frequency noise, thereby remaining the operation performance of the fan without causing uncomfortable of users.

SUMMARY OF THE INVENTION

An objective of this disclosure is to provide a fan with lower high-frequency noise and still remaining the operation performance of the fan.

This disclosure provides a fan, which comprises a frame, an impeller and a motor. The impeller is disposed in the frame and comprises a hub, a plurality of annular blades and a plurality of spacers. The annular blades are stacked along an axial direction of the hub and disposed around an outer periphery of the hub. The extension directions of the annular blades are perpendicular to the axial direction of the hub. Each of the spacers is disposed between the two adjacent annular blades. The motor is disposed in the frame and drives the impeller to rotate to induce an airflow. A thickness of each of the annular blades is smaller than or equals to 0.2 mm.

In one embodiment, each annular blade has an inner periphery, and a gap is provided between the inner periphery and the hub.

In one embodiment, a bottom portion of the hub has an extension portion extending outwardly and perpendicular to the axial direction, and the annular blades are stacked and disposed at one side of the extension portion.

In one embodiment, a bottom portion of the hub has an extension portion extending outwardly and perpendicular to the axial direction, and the annular blades are stacked and disposed at two sides of the extension portion.

In one embodiment, the hub further comprises a plurality of supporting columns, the supporting columns are disposed at the extension portion, each of the annular blades comprises a plurality of through holes, and the supporting columns pass through the through holes, respectively.

In one embodiment, the spacers are disposed around the supporting columns, respectively.

In one embodiment, the supporting columns are separately disposed on the extension portion with equivalent intervals.

In one embodiment, the supporting columns are separately disposed on the extension portion with inequivalent intervals.

In one embodiment, each annular blade further comprises a plurality of spokes and at least an inner ring, the inner ring is disposed on and connected to the outer periphery of the hub, and two ends of the spoke are connected to the inner periphery and the inner ring of the annular blade.

In one embodiment, the spacers are separately disposed on the inner rings of the annular blades, respectively.

In one embodiment, a bottom portion of the hub has a protrusion portion extending outwardly and perpendicular to the axial direction, and the annular blades are disposed on the protrusion portion of the hub by stacking the inner rings on the protrusion portion.

In one embodiment, a ratio of a thickness of each of the spacers to that of each of the annular blades is greater than or equal to 1.

In one embodiment, a ratio of an inner radius of the annular blades to an outer radius of the annular blades is greater than or equal to 0.5.

In one embodiment, the frame forms a guiding surface at an inner periphery of an air inlet of the fan.

As mentioned above, the fan of this disclosure comprises a plurality of annular blades stacked along an axial direction of the hub and disposed around an outer periphery of the hub, and the extension directions of the annular blades are perpendicular to the axial direction of the hub. Thus, the fan of this disclosure can induce the airflow by the shearing force. Compared with the convention fan that utilizes the friction of the blades to induce the airflow, the fan of this disclosure can decrease the high-frequency noise and increase the air pressure, thereby avoiding the uncomfortable of users and remaining the operation performance of the fan.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will become more fully understood from the subsequent detailed description and accompanying drawings, which are given by way of illustration only, and thus are not limitative of the present invention, and wherein:

FIG. 1A is a schematic diagram showing a fan according to an embodiment of this disclosure;

FIG. 1B is a sectional view of the fan of FIG. 1A;

FIG. 2A is a schematic diagram showing the impeller of the fan according to a first embodiment of this disclosure;

FIG. 2B is a sectional view of the impeller of FIG. 2A;

FIG. 2C is an exploded view of the impeller of FIG. 2A;

FIG. 3A is a schematic diagram showing the impeller of the fan according to a second embodiment of this disclosure;

FIG. 3B is a sectional view of the impeller of FIG. 3A;

FIG. 4A is a schematic diagram showing the impeller of the fan according to a third embodiment of this disclosure;

FIG. 4B is a sectional view of the impeller of FIG. 4A;

FIG. 4C is an exploded view of the impeller of FIG. 4A; and

FIG. 4D is a sectional view of a modified impeller of the fan according to the third embodiment of this disclosure.

DETAILED DESCRIPTION OF THE INVENTION

The present invention will be apparent from the following detailed description, which proceeds with reference to the accompanying drawings, wherein the same references relate to the same elements.

This disclosure provides a fan that can decrease the high-frequency noise and increase the air pressure, thereby avoiding the uncomfortable of users and remaining the operation performance of the fan. The structure and features of the fan of this disclosure will be described in the following embodiments.

FIG. 1A is a schematic diagram showing a fan according to an embodiment of this disclosure, and FIG. 1B is a sectional view of the fan of FIG. 1A. Referring to FIGS. 1A and 1B, the fan comprises a frame 1, an impeller 2, and a motor 3. The frame 1 comprises an air inlet 12 and an air outlet 13. The motor 3 is disposed in the frame 1 and drives the impeller 2 to rotate, thereby inducing an airflow from the air inlet 12 to the air outlet 13. In this embodiment, the motor 3 comprises a shaft 31, a magnetic shell 32, a magnetic element 33 and a stator structure 34. The magnetic shell 32 is disposed inside the impeller 2, and one end of the shaft 31 is connected to the magnetic shell 32. The magnetic element 33 is disposed on the inner periphery of the magnetic shell 32 and is located corresponding to the stator structure 34. The shaft 31 and the magnetic shell 32 can be combined by, for example, laser welding.

In this embodiment, a guiding curved surface 11 is formed on the inner periphery of the air inlet 12 of the frame 1 for guiding the airflow to enter the frame 1 along the air input direction F.

FIG. 2A is a schematic diagram showing the impeller of the fan according to a first embodiment of this disclosure, and FIG. 2B is a sectional view of the impeller of FIG. 2A. Referring to FIGS. 2A and 2B, the impeller 2a comprises a hub 21a, a plurality of annular blades 22a, and a plurality of spacers 23a. The annular blades 22a are stacked along an axial direction L1 of the hub 21a and disposed around an outer periphery of the hub 21a. The extension directions of the annular blades 22a are perpendicular to the axial direction L1 of the hub 21a. In more detailed, the axial direction L1 of the hub 21a is parallel to a Y-axis direction, and the extension directions of the annular blades 22a are parallel to an X-axis direction. The X-axis direction and the Y-axis direction are perpendicular to each other. Based on the configuration of the extension directions of the annular blades 22a and the axial direction L1 of the hub 21a, which are perpendicular to each other, the surface of the annular blades 22a can generate the shearing force caused by viscosity to induce the airflow, thereby decreasing the high-frequency noise generated by the fan.

In this embodiment, each of the spacers 23a is disposed between the two adjacent annular blades 22a, for separating the two adjacent annular blades 22a. The thickness of each of the annular blades 22a is preferably smaller than or equals to 0.2 mm. The ratio of a thickness of the spacer 23a to that of the annular blade 22a is preferably greater than or equal to 1. In other words, the thickness of the spacer 23a is equal to or larger than that of the annular blade 22a. In this embodiment, the height of the fan can be, for example but not limited to, less than or equal to 30 mm, and the number of the annular blades 22a can be, for example but not limited to, less than or equal to 62. In particular, the spacer 23a and the annular blade 22a can be integrally formed as a single piece. For example, the spacer 23a can be a protrusion on the annular blade 22a or a curved portion disposed at the tail of the annular blade 22a, and this disclosure is not limited. That is, each of the spacer 23a can be any structure that can form a gap between the two adjacent annular blades 22a.

FIG. 2C is an exploded view of the impeller of FIG. 2A. Referring to FIGS. 2B and 2C, the annular blade 22a has an inner periphery 221a, and a gap G is provided between the inner periphery 221a and the hub 21a. Preferably, a ratio of an inner radius R1 of the annular blades 22a to an outer radius R2 of the annular blades 22a is greater than or equal to 0.5. Specifically, the gap G is configured for guiding the airflow, so that the airflow can pass through the gap G between the annular blades 22a and the hub 21a, the spaces between the annular blades 22a (formed by the spacers 23a), and the air outlet of the fan.

In this embodiment, the bottom portion of the hub 21a has an extension portion 211a extending outwardly and perpendicular to the axial direction L1, and the annular blades 22a are stacked and disposed at one side of the extension portion 211a. The hub 21a further comprises a plurality of supporting columns 212a, which are disposed at the extension portion 211a. Each annular blade 22a comprises a plurality of through holes 222a, and the supporting columns 212a pass through the through holes 222a, respectively. The spacers 23a are disposed around the supporting columns 212a. In particular, the supporting columns 212a can be disposed on the extension portion 211a of the hub 21a by, for example but not limited to, laser welding or injection molding.

As shown in FIG. 2C, the extension portion 211a of the hub 21a is configured with five supporting columns 212a, which are arranged with equivalent intervals. The annular blades 22a are stacked and disposed on the extension portion 211a. The supporting columns 212a pass through the corresponding through holes 222a of one annular blade 22a, and then the spaces 23a are disposed around the corresponding supporting columns 212a. Afterwards, another annular blade 22a is stacked on the previous annular blade 22a. After disposing the annular blades 22a and spacers 23a alternately, the annular blades 22a can be stacked and disposed at one side of the extension portion 211a. To be noted, although the figure shows five supporting columns 212a disposed with equivalent intervals, the number of the configured supporting columns 212a can be adjusted based on the requirement of the user. In addition, the supporting columns 212a can be separately disposed on the extension portion 211a with inequivalent intervals (e.g. the supporting columns 212a of FIG. 2B). This disclosure is not limited.

In this embodiment, the hub 21a can further comprise a plurality of fixing members 213a for firmly fixing the annular blades 22a on the supporting columns 212a. The fixing members 213a can be connected to the supporting columns 212a by welding or screwing. As shown in the figures, after disposing the annular blades 22a and the spacers 23a alternately, the fixing members 213a are provided to firmly fix the annular blades 22a and the supporting columns 212a. This configuration can prevent the noise caused by the unstable annular blades 22a while the impeller 2a is rotating. If the supporting columns 212a are made of plastic, it is also possible to melt the end portions of the supporting columns 212a for fixing and restricting the annular blades 22a. This approach can also achieve the same function of the fixing members 213a.

FIG. 3A is a schematic diagram showing the impeller of the fan according to a second embodiment of this disclosure, and FIG. 3B is a sectional view of the impeller of FIG. 3A. As shown in FIG. 3B, the fan impeller 2b comprises a hub 21b, a plurality of annular blades 22b, and a plurality of spacers 23b. The impeller 2b of FIG. 3B is mostly the same as the impeller 2a of FIG. 2B. Different from the impeller 2a, the annular blades 22b of the impeller 2b are disposed at two sides of the extension portion 211b, and the supporting columns 212b are disposed at two sides of the extension portion 211b. In other words, the impeller 2b includes two air input directions F and F′, but the impeller 2a only includes one air input direction F.

FIG. 4A is a schematic diagram showing the impeller of the fan according to a third embodiment of this disclosure, and FIG. 4B is a sectional view of the impeller of FIG. 4A. As shown in FIGS. 4A and 4B, the impeller 2c comprises a hub 21c, a plurality of annular blades 22c, and a plurality of spacers 23c. In this embodiment, the shaft 31 and the magnetic shell 32 are not shown. The annular blades 22c are stacked along an axial direction L1 of the hub 21c and disposed around an outer periphery of the hub 21c. The extension directions of the annular blades 22c are perpendicular to the axial direction L1 of the hub 21c. In more detailed, the axial direction L1 of the hub 21c is parallel to a Y-axis direction, and the extension directions of the annular blades 22c are parallel to an X-axis direction. The X-axis direction and the Y-axis direction are perpendicular to each other. Based on the configuration of the extension directions of the annular blades 22c and the axial direction L1 of the hub 21c, which are perpendicular to each other, the surface of the annular blades 22c can generate the shearing force caused by viscosity to induce the airflow, thereby decreasing the high-frequency noise generated by the fan.

In this embodiment, the annular blade 22c has an inner periphery 221c, and a gap G is provided between the inner periphery 221c and the hub 21c. Specifically, the gap G is configured for guiding the airflow, so that the airflow can pass through the gap G between the annular blades 22c and the hub 21c, the spaces between the annular blades 22c, and the air outlet of the fan.

In this embodiment, the annular blade 22c further comprises a plurality of spokes 223c and an inner ring 224c. The inner ring 224c is disposed on and connected to the outer periphery of the hub 21c, and two ends of the spoke 223c are connected to the inner periphery 221c and the inner ring 224c of the annular blade 22c. To be noted, although the figure shows five spokes 223c disposed between the inner periphery 221c and the inner ring 224c of the annular blade 22c with equivalent intervals, the number of the configured spokes 223c can be adjusted. In addition, the spokes 223c can be separately disposed with inequivalent intervals (not shown). This disclosure is not limited.

In this embodiment, each of the spacers 23c is disposed between the two adjacent inner rings 224c for separating the two adjacent annular blades 22c. The thickness of the annular blades 22c, the ratio of the thickness of the spacers 23c to that of the annular blades 22c, and the ratio of the inner radius to the outer radius of the annular blades 22c can be referred to the above-mentioned impeller 2a, so the detailed descriptions thereof will be omitted.

FIG. 4C is an exploded view of the impeller of FIG. 4A. In this embodiment, as shown in FIGS. 4B and 4C, a bottom portion of the hub 21c has a protrusion portion 211c extending outwardly and perpendicular to the axial direction L1, and the annular blades 22c are disposed on the protrusion portion 211c of the hub 21c by stacking the inner rings 224c on the protrusion portion 211c. The inner ring 224c of one annular blade 22c passes through the hub 21c and disposed on the protrusion portion 211c, and then the space 23c also passes through the hub 21c. Afterwards, another annular blade 22c is stacked on the previous annular blade 22c. After disposing the annular blades 22c and spacers 23c alternately, the annular blades 22c can be stacked and disposed on the protrusion portion 211c. To be noted, although the figure shows that the impeller 2c comprises five annular blades 22c and four spacers 23c, the numbers of the configured annular blades 22c and spacers 23c can be adjusted based on the requirement of the user. This disclosure is not limited.

FIG. 4D is a sectional view of a modified impeller of the fan according to the third embodiment of this disclosure. The structure of the impeller 2c′ as shown in FIG. 4D is similar to the structure of the impeller 2c as shown in FIG. 4B. Different from the impeller 2c of FIG. 4B, the impeller 2c′ shown in FIG. 4D does not comprise the gap G between the hub 21c and the annular blade 22c′, which is located closest to the protrusion portion 211c. In other words, the annular blade 22c′ located closest to the protrusion portion 211c does not have the spoke 223c. Accordingly, the impeller 2c′ has only one air input direction F.

In the above embodiments, the annular blades 22a, 22c, 22c, and 22c′ are made of metal, such as, for example but not limited to, stainless steel, aluminum alloy, or titanium alloy. The hubs 21a, 21b, and 21c are made of plastic or metal.

In summary, the impeller of the fan of this disclosure comprises a plurality of annular blades stacked along an axial direction of the hub and disposed around an outer periphery of the hub, and the extension directions of the annular blades are perpendicular to the axial direction of the hub. According to this design, the fan of this disclosure can induce the airflow by the shearing force, thereby decreasing the high-frequency noise. In addition, since the annular blades of this disclosure have a thinner thickness, it is possible to configure more annular blades, thereby increasing the performance of inducing airflow by the fan.

Although the present invention has been described with reference to specific embodiments, this description is not meant to be construed in a limiting sense. Various modifications of the disclosed embodiments, as well as alternative embodiments, will be apparent to persons skilled in the art. It is, therefore, contemplated that the appended claims will cover all modifications that fall within the true scope of the present invention.

Claims

1. A fan impeller, comprising: a hub;a plurality of annular blades stacked along an axial direction of the hub and disposed around an outer periphery of the hub, wherein extension directions of the annular blades are perpendicular to the axial direction of the hub; anda plurality of spacers, each of the spacers is disposed between the two adjacent annular blades;wherein each of the annular blades has an inner periphery, and a gap is provided between the inner periphery and the hub;wherein each of the annular blades further comprises a plurality of spokes and an inner ring, the inner ring is disposed on and connected to the outer periphery of the hub, and two ends of the spoke are connected to the inner periphery and the inner ring of the annular blade;wherein the spacers are separately disposed on the inner rings of the annular blades, respectively.

2. The fan impeller according to claim 1, wherein a bottom portion of the hub has an extension portion extending outwardly and perpendicular to the axial direction.

3. The fan impeller according to claim 2, wherein the annular blades are stacked and disposed at one side of the extension portion, or the annular blades are stacked and disposed at two sides of the extension portion.

4. The fan impeller according to claim 3, wherein the hub further comprises a plurality of supporting columns disposed at the extension portion, each of the annular blades comprises a plurality of through holes, and the supporting columns pass through the through holes, respectively.