CENTRIFUGAL FAN WITH A MULTISTAGE IMPELLER
A centrifugal fan with a multistage impeller includes a hub and a multistage impeller having at least two stages of blade assemblies. The hub has a top section and a circumferential section extending from the top section. At least one extension section outward extends from the circumferential section. The multistage impeller is connected with one end of the extension section. The multistage impeller includes a first-stage blade assembly and a second-stage blade assembly. The second-stage blade assembly has a diameter larger than that of the first-stage blade assembly. The centrifugal fan can be installed in an application environment with limited space without being interfered with by peripheral parts. Also, the centrifugal fan is able to provide an optimal flow and wind pressure at the same rotational speed to lower the load on the motor and reduce the noise.
1. Field of the Invention
The present invention relates generally to a centrifugal fan with a multistage impeller, and more particularly to a centrifugal fan having at least two stages of blade assemblies. The centrifugal fan can be installed in an application environment with limited space without being interfered with by peripheral parts. Also, the centrifugal fan is able to provide an optimal flow and wind pressure at the same rotational speed to lower the load on the motor and reduce the noise.
2. Description of the Related Art
Recently, thanks to rapid advance of electronic industries, the performances of various electronic components have been more and more promoted. To increase the operation speed of the electronic component, the number of the chips in the electronic component is continuously increased and the processing speed of the chip sets in the electronic component is continuously enhanced. Under such circumstance, the chips will generate high heat when working. The heat generated by the chips must be quickly dissipated. Otherwise, the temperature of the electronic component will rise very quickly to cause deterioration of the performances of the electronic component, slowdown of the operation speed of the electronic component, crash or even burnout of the electronic component. Therefore, it has become an important issue how to quickly dissipate the heat generated by the chips. In general, a cooling fan is used as a heat dissipation device for dissipating the heat.
Various fans are widely used in different fields for ventilation, exhaustion, air exchange, temperature control, etc. According to the function and property, the fans available in the current market can be classified into three major types, that is, centrifugal fans, diagonal flow fans and axial flow fans. These fans are applied to different sites to meet different requirements in working.
As aforesaid, the centrifugal fan 1 has a unified diameter. Therefore, when installing the centrifugal fan 1, it often takes place that it is impossible to install or use the centrifugal fan 1 due to limitation of space or interference of peripheral parts. Under such circumstance, it must be compromised to install and use a smaller centrifugal fan with a unified diameter. The smaller centrifugal fan often fails to provide a flow meeting the designed flow value. In this case, it is necessary to increase the rotational speed of the smaller centrifugal fan. As a result, the centrifugal fan will make greater noise and the load on the motor will be increased.
According to the above, the conventional centrifugal fan has the following shortcomings:
- 1. The installation space of the conventional centrifugal fan is limited.
- 2. The installation of the conventional centrifugal fan is subject to interference of peripheral parts.
- 3. The conventional centrifugal fan can hardly provide a flow meeting the designed flow value.
- 4. The conventional centrifugal fan will make greater noise and the load on the motor will be increased.
A primary object of the present invention is to provide a centrifugal fan with a multistage impeller having at least two stages of blade assemblies. The multistage impeller has non-unified diameters. Therefore, the centrifugal fan can be installed in an application environment with limited space without being interfered with by peripheral parts.
A further object of the present invention is to provide the above centrifugal fan with the multistage impeller. The centrifugal fan is able to provide an optimal flow and wind pressure at the same rotational speed.
A still further object of the present invention is to provide the above centrifugal fan with the multistage impeller. The centrifugal fan is operable with lower load on the motor and reduced noise.
To achieve the above and other objects, the centrifugal fan with the multistage impeller of the present invention includes a hub and a multistage impeller having at least two stages of blade assemblies. The hub has a top section and a circumferential section extending from a periphery of the top section. At least one extension section outward extends from the circumferential section in a direction away from the top section. The multistage impeller includes a first-stage blade assembly and a second-stage blade assembly. The first-stage blade assembly is connected with one end of the extension section, which end is distal from the circumferential section. The second-stage blade assembly is positioned on one side of the first-stage blade assembly. Each of the first-stage blade assembly and the second-stage blade assembly includes multiple blades annularly arranged around the hub. A first connection section is connected between each two adjacent blades of the first-stage blade assembly. The blades of the first-stage blade assembly are annularly connected with each other by means of the first connection sections. A second connection section is connected between each two adjacent blades of the second-stage blade assembly. The blades of the second-stage blade assembly are annularly connected with each other by means of the second connection sections. The second-stage blade assembly has a diameter larger than that of the first-stage blade assembly.
The structure and the technical means adopted by the present invention to achieve the above and other objects can be best understood by referring to the following detailed description of the preferred embodiments and the accompanying drawings, wherein:
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The extension section 33 is connected to the first connection section 411 of the first-stage blade assembly 41. The multiple blades of the first-stage blade assembly 41 are arranged at equal intervals and perpendicularly extend from the first connection sections 411. The blades are annularly connected with each other via the first connection sections 411. The first-stage annular plate 412 is disposed on the upper side of the first-stage blade assembly 41. The first-stage annular plate 412 extends along an outer circumference of the upper side of the first-stage blade assembly 41. The second-stage blade assembly 42 is arranged on the other side of the first-stage annular plate 412. The first-stage annular plate 412 extends along an inner circumference of lower side of the second-stage blade assembly 42. Accordingly, the second-stage blade assembly 42 has a diameter larger than that of the first-stage blade assembly 41. Therefore, the combination of the first-stage blade assembly 41 and the second-stage blade assembly 42 has non-unified diameters.
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According to the above arrangement, the centrifugal fan with the multistage impeller of the present invention has the following advantages:
- 1. The centrifugal fan with the multistage impeller of the present invention can be installed in an application environment with limited space.
- 2. The centrifugal fan with the multistage impeller of the present invention can be installed in an application environment without being interfered with by peripheral parts.
- 3. The centrifugal fan with the multistage impeller of the present invention is able to provide an optimal flow and wind pressure at the same rotational speed.
- 4. The centrifugal fan with the multistage impeller of the present invention is operable with lower load on the motor and reduced noise.
The above embodiments are only used to illustrate the present invention, not intended to limit the scope thereof. It is understood that many changes and modifications of the above embodiments can be made without departing from the spirit of the present invention. The scope of the present invention is limited only by the appended claims.
Claims
1. A centrifugal fan with a multistage impeller, the centrifugal fan comprising:
- a hub having a top section and a circumferential section extending from the top section, at least one extension section outward extending from the circumferential section in a direction away from the top section; and
- a multistage impeller having at least two stages of blade assemblies, the multistage impeller including a first-stage blade assembly and a second-stage blade assembly, each of the first-stage blade assembly and the second-stage blade assembly including multiple blades annularly arranged around the hub, the first-stage blade assembly being connected with one end of the extension section, the second-stage blade assembly being positioned on one side of the first-stage blade assembly, the second-stage blade assembly having a diameter larger than that of the first-stage blade assembly.
2. The centrifugal fan with the multistage impeller as claimed in claim 1, wherein the centrifugal fan is mounted in a multistage fan housing.
3. The centrifugal fan with the multistage impeller as claimed in claim 1, wherein a first connection section is connected between each two adjacent
4. The centrifugal fan with the multistage impeller as claimed in claim 1, wherein a second connection section is connected between each two adjacent blades of the second-stage blade assembly, the blades of the second-stage blade assembly being annularly connected with each other by means of the second connection sections to form the second-stage blade assembly in an annular form.
5. The centrifugal fan with the multistage impeller as claimed in claim 1, wherein a first-stage annular plate is positioned between the first-stage blade assembly and the second-stage blade assembly, the second-stage blade assembly being arranged on one side of the first-stage blade assembly via the first-stage annular plate.
6. The centrifugal fan with the multistage impeller as claimed in claim 5, wherein a second-stage annular plate is positioned on the other side of the second-stage blade assembly, which side is distal from the first-stage blade assembly, a third-stage blade assembly being arranged on the other side of the second-stage annular plate.
7. The centrifugal fan with the multistage impeller as claimed in claim 6, wherein the second-stage annular plate has a diameter larger than that of the first-stage annular plate.
8. The centrifugal fan with the multistage impeller as claimed in claim 6, wherein the third-stage blade assembly includes multiple blades annularly arranged around the hub, a third connection section being connected between each two adjacent blades of the third-stage blade assembly, the blades of the third-stage blade assembly being annularly connected with each other by means of the third connection sections to form the third-stage blade assembly in an annular form.
9. The centrifugal fan with the multistage impeller as claimed in claim 8, wherein the third-stage blade assembly has a diameter larger than that of the second-stage blade assembly.
Type: Application
Filed: Jul 7, 2011
Publication Date: Jan 10, 2013
Inventor: Jin-Hsun Liu (New Taipei City)
Application Number: 13/177,889
International Classification: F01D 1/10 (20060101); F01D 5/00 (20060101);