US20070248459A1 - Centrifugal fan - Google Patents
Centrifugal fan Download PDFInfo
- Publication number
- US20070248459A1 US20070248459A1 US11/477,371 US47737106A US2007248459A1 US 20070248459 A1 US20070248459 A1 US 20070248459A1 US 47737106 A US47737106 A US 47737106A US 2007248459 A1 US2007248459 A1 US 2007248459A1
- Authority
- US
- United States
- Prior art keywords
- centrifugal impeller
- housing
- driving mechanism
- centrifugal
- airflow
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
Images
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D29/00—Details, component parts, or accessories
- F04D29/26—Rotors specially for elastic fluids
- F04D29/28—Rotors specially for elastic fluids for centrifugal or helico-centrifugal pumps for radial-flow or helico-centrifugal pumps
- F04D29/281—Rotors specially for elastic fluids for centrifugal or helico-centrifugal pumps for radial-flow or helico-centrifugal pumps for fans or blowers
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D29/00—Details, component parts, or accessories
- F04D29/26—Rotors specially for elastic fluids
- F04D29/28—Rotors specially for elastic fluids for centrifugal or helico-centrifugal pumps for radial-flow or helico-centrifugal pumps
- F04D29/30—Vanes
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D29/00—Details, component parts, or accessories
- F04D29/66—Combating cavitation, whirls, noise, vibration or the like; Balancing
- F04D29/68—Combating cavitation, whirls, noise, vibration or the like; Balancing by influencing boundary layers
- F04D29/681—Combating cavitation, whirls, noise, vibration or the like; Balancing by influencing boundary layers especially adapted for elastic fluid pumps
Definitions
- Taiwan Application Serial Number 95114589 filed on Apr. 24, 2006, the disclosure of which is hereby incorporated by reference herein in its entirety.
- the present invention relates to a centrifugal fan. More particularly, the present invention relates to a centrifugal fan with noise reduction functionality.
- a centrifugal fan employs a spiral flow channel design to convert dynamic air energy into static pressure so as to overcome the high air flow impedance inside the notebook PC case housing.
- high static pressure generating centrifugal fans face the dual challenge of reducing noise and improving heat dissipation efficiency.
- Noise can be divided into broadband noise and narrowband noise, wherein narrowband noise is preferably eliminated from a centrifugal fan.
- FIG. 1 illustrates a perspective view of a conventional centrifugal fan.
- a centrifugal fan 100 includes a spiral housing 102 , which has a motor (not illustrated) and an internal centrifugal impeller 104 .
- the motor rotates the centrifugal impeller 104
- driven airflow moves along a spiral flow channel 110 .
- a wake flow 112 coming out of blades 106 of the centrifugal impeller 104 , crashes against the inner walls of the spiral flow channel 110 , thereby creating a BPF (Blade Pass Frequency).
- BPF often becomes high-frequency, narrow-band noise, especially in a high static pressure generating centrifugal fan.
- BPF also generates an annoying high-frequency, narrow-band noise when the wake flow 112 hits a cut-off 103 of a centrifugal fan 100 .
- a centrifugal fan includes a spiral housing, a driving mechanism and multiple internally mounted impellers.
- the driving mechanism and the centrifugal impeller, rotated by the driving mechanism, are installed in the spiral housing.
- a spiral flow channel exists between the centrifugal impeller and the spiral housing.
- the centrifugal impeller rotates, airflow is sucked axially into the spiral housing through an inlet opening and moves along each blade of the centrifugal impeller into the spiral flow channel.
- the centrifugal impeller includes a hub and multiple blades.
- Each of the blades is secured to the hub at one end and has at least one vertical convex strip or vertical concave strip at an opposite end, wherein the vertical convex strip or vertical concave strip on each blade disturbs the airflow across thereof and reduces narrow-band noises.
- each blade of the centrifugal fan has a vertical convex strip or a vertical concave strip at an end of the windward side so as to disturb airflows across thereof, thereby decreasing high-frequency and narrow-band noises.
- Such centrifugal impeller design overcomes a challenge between noise reducing and heat dissipation efficiency improving in a notebook computer.
- FIG. 1 illustrates a perspective view of a conventional centrifugal fan
- FIG. 2 illustrates a cross-sectional view of a centrifugal fan according to one preferred embodiment of this invention.
- FIGS. 3A and 3B respectively illustrate two types of centrifugal impellers according to one preferred embodiment of this invention.
- FIG. 2 illustrates a cross-sectional view of a centrifugal fan according to one preferred embodiment of this invention.
- a centrifugal fan 200 has a spiral housing 202 .
- a centrifugal impeller and a driving mechanism 208 (such as a motor) are installed in the spiral housing 202 .
- the centrifugal impeller includes a hub 204 and multiple blades 206 (like blades 106 in FIG. 1 ).
- the driving mechanism 208 rotates the centrifugal impeller, rotating blades 206 constantly suck airflow along the direction 214 .
- the airflow moves axially into the spiral housing 202 through an inlet opening 202 a , and then moves along each of blades 206 (i.e.
- a vertical convex strip 205 a or a vertical concave strip 205 b is formed at the end and the windward side of each blade 206 to disturb the airflow across thereof.
- a conventional blade has a flat surface on its windward side such that the airflow along the direction 216 has a bigger impact against the spiral flow channel 207 (i.e. inner walls of the housing 202 ). The bigger the impact against the spiral flow channel 207 , the more high-frequency and narrow-band noises are generated.
- a width d of the vertical convex strip 205 a or the vertical concave strip 205 b is approximately equal to the thickness of the blade 206 .
- the width d is not a constant value and its optimum value could vary according to the blade length, blade rotation speed, flow channel shape etc, and does not influence the dissipation performance of the centrifugal fan. More than one vertical convex strip 205 a or vertical concave strip 205 b may be formed on the blade 206 as long as the dissipation performance of the centrifugal fan is not influenced.
- FIGS. 3A and 3B respectively illustrates two types of centrifugal impellers according to one preferred embodiment of this invention.
- FIG. 3A a hub 204 and one blade 206 a of blades 206 are illustrated.
- the hub 204 and the blade 206 a both rotate in the direction 210 .
- the vertical concave strips 205 a are formed on the windward side of the blade 206 a , and the airflow 212 a is therefore disturbed and its impact on the cut-off 203 (like the cut-off 103 in FIG. 1 ) is reduced, thereby decreasing the high-frequency, narrow-band noise.
- FIG. 3B a hub 204 and one blade 206 b of the blades 206 are illustrated.
- the hub 204 and the blade 206 b both rotate in the direction 210 .
- the vertical convex strips 205 b are formed on the windward side of the blade 206 b , and the airflow 212 b is therefore disturbed and its impact on the cut-off 203 (like cut-off 103 in FIG. 1 ) is reduced, thereby decreasing the high-frequency and narrow-band noises.
- each blade of the centrifugal fan has a vertical convex strip or a vertical concave strip at the end of the blade, at the windward side so as to disturb the airflow across thereof, thereby decreasing the high-frequency, narrow-band noise.
- a centrifugal impeller design reduces noise and improves heat dissipation efficiency in a notebook PC.
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Structures Of Non-Positive Displacement Pumps (AREA)
Abstract
A centrifugal fan includes a spiral housing, a driving mechanism and multiple internally mounted impellers. The driving mechanism and the centrifugal impeller, rotated by the driving mechanism, are installed in the spiral housing. A spiral flow channel is defined between the centrifugal impeller and the spiral housing. When the centrifugal impeller rotates, airflow is sucked axially into the spiral housing through an inlet opening and moves along each blade of the centrifugal impeller into the spiral flow channel. The centrifugal impeller includes a hub and multiple blades. Each blade is secured to the hub at one end and has at least one vertical convex strip or vertical concave strip at an opposite end, wherein the vertical convex strip or vertical concave strip on each of blade disturbs the airflow across thereof and reduces narrow-band noise.
Description
- The present application is based on, and claims priority from, Taiwan Application Serial Number 95114589, filed on Apr. 24, 2006, the disclosure of which is hereby incorporated by reference herein in its entirety.
- 1. Field of Invention
- The present invention relates to a centrifugal fan. More particularly, the present invention relates to a centrifugal fan with noise reduction functionality.
- 2. Description of Related Art
- As notebook PCs become thinner, less space is available for heat convection and heat dissipation components inside the notebook PC case housing. High-frequency components, such as the CPU (central processing unit) and graphics processing chip, also place limitations on heat dissipation designs. Thus, the mainstream method to dissipate heat is forced heat convection via a centrifugal fan.
- A centrifugal fan employs a spiral flow channel design to convert dynamic air energy into static pressure so as to overcome the high air flow impedance inside the notebook PC case housing. However, high static pressure generating centrifugal fans face the dual challenge of reducing noise and improving heat dissipation efficiency. Noise can be divided into broadband noise and narrowband noise, wherein narrowband noise is preferably eliminated from a centrifugal fan.
-
FIG. 1 illustrates a perspective view of a conventional centrifugal fan. Acentrifugal fan 100 includes aspiral housing 102, which has a motor (not illustrated) and an internalcentrifugal impeller 104. When the motor rotates thecentrifugal impeller 104, driven airflow moves along aspiral flow channel 110. Awake flow 112, coming out ofblades 106 of thecentrifugal impeller 104, crashes against the inner walls of thespiral flow channel 110, thereby creating a BPF (Blade Pass Frequency). BPF often becomes high-frequency, narrow-band noise, especially in a high static pressure generating centrifugal fan. BPF also generates an annoying high-frequency, narrow-band noise when thewake flow 112 hits a cut-off 103 of acentrifugal fan 100. - It is therefore an objective of the present invention to provide a centrifugal fan with a noise reduction functionality so as to reduce noise and improve the overall heat dissipation efficiency.
- In accordance with the foregoing and other objectives of the present invention, a centrifugal fan includes a spiral housing, a driving mechanism and multiple internally mounted impellers. The driving mechanism and the centrifugal impeller, rotated by the driving mechanism, are installed in the spiral housing. A spiral flow channel exists between the centrifugal impeller and the spiral housing. When the centrifugal impeller rotates, airflow is sucked axially into the spiral housing through an inlet opening and moves along each blade of the centrifugal impeller into the spiral flow channel. The centrifugal impeller includes a hub and multiple blades. Each of the blades is secured to the hub at one end and has at least one vertical convex strip or vertical concave strip at an opposite end, wherein the vertical convex strip or vertical concave strip on each blade disturbs the airflow across thereof and reduces narrow-band noises.
- Thus, each blade of the centrifugal fan has a vertical convex strip or a vertical concave strip at an end of the windward side so as to disturb airflows across thereof, thereby decreasing high-frequency and narrow-band noises. Such centrifugal impeller design overcomes a challenge between noise reducing and heat dissipation efficiency improving in a notebook computer.
- It is to be understood that both the foregoing general description and the following detailed description are by examples, and are intended to provide further explanation of the invention as claimed.
- The accompanying drawings are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification. The drawings illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention. In the drawings,
-
FIG. 1 illustrates a perspective view of a conventional centrifugal fan; -
FIG. 2 illustrates a cross-sectional view of a centrifugal fan according to one preferred embodiment of this invention; and -
FIGS. 3A and 3B respectively illustrate two types of centrifugal impellers according to one preferred embodiment of this invention. - Reference will now be made in detail to the present preferred embodiments of the invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers are used in the drawings and the description to refer to the same or like parts.
-
FIG. 2 illustrates a cross-sectional view of a centrifugal fan according to one preferred embodiment of this invention. Acentrifugal fan 200 has aspiral housing 202. A centrifugal impeller and a driving mechanism 208 (such as a motor) are installed in thespiral housing 202. The centrifugal impeller includes ahub 204 and multiple blades 206 (likeblades 106 inFIG. 1 ). When thedriving mechanism 208 rotates the centrifugal impeller, rotatingblades 206 constantly suck airflow along thedirection 214. The airflow moves axially into thespiral housing 202 through an inlet opening 202 a, and then moves along each of blades 206 (i.e. along the direction 216), and finally into a spiral flow channel 207 (like thespiral flow channel 110 inFIG. 1 ). In order to distribute the airflow in thedirection 216, avertical convex strip 205 a or a verticalconcave strip 205 b is formed at the end and the windward side of eachblade 206 to disturb the airflow across thereof. On the contrary, a conventional blade has a flat surface on its windward side such that the airflow along thedirection 216 has a bigger impact against the spiral flow channel 207 (i.e. inner walls of the housing 202). The bigger the impact against thespiral flow channel 207, the more high-frequency and narrow-band noises are generated. - In this preferred embodiment, a width d of the
vertical convex strip 205 a or the verticalconcave strip 205 b is approximately equal to the thickness of theblade 206. However, the width d is not a constant value and its optimum value could vary according to the blade length, blade rotation speed, flow channel shape etc, and does not influence the dissipation performance of the centrifugal fan. More than onevertical convex strip 205 a or verticalconcave strip 205 b may be formed on theblade 206 as long as the dissipation performance of the centrifugal fan is not influenced. -
FIGS. 3A and 3B respectively illustrates two types of centrifugal impellers according to one preferred embodiment of this invention. - In
FIG. 3A , ahub 204 and oneblade 206 a ofblades 206 are illustrated. Thehub 204 and theblade 206 a both rotate in thedirection 210. The verticalconcave strips 205 a are formed on the windward side of theblade 206 a, and theairflow 212 a is therefore disturbed and its impact on the cut-off 203 (like the cut-off 103 inFIG. 1 ) is reduced, thereby decreasing the high-frequency, narrow-band noise. - In
FIG. 3B , ahub 204 and oneblade 206 b of theblades 206 are illustrated. Thehub 204 and theblade 206 b both rotate in thedirection 210. Thevertical convex strips 205 b are formed on the windward side of theblade 206 b, and theairflow 212 b is therefore disturbed and its impact on the cut-off 203 (like cut-off 103 inFIG. 1 ) is reduced, thereby decreasing the high-frequency and narrow-band noises. - According to the preferred embodiments of the present invention, each blade of the centrifugal fan has a vertical convex strip or a vertical concave strip at the end of the blade, at the windward side so as to disturb the airflow across thereof, thereby decreasing the high-frequency, narrow-band noise. Such a centrifugal impeller design reduces noise and improves heat dissipation efficiency in a notebook PC.
- It will be apparent to those skilled in the art that various modifications and variations can be made to the structure of the present invention without departing from the scope or spirit of the invention. In view of the foregoing, it is intended that the present invention cover modifications and variations of this invention provided they fall within the scope of the following claims and their equivalents.
Claims (4)
1. A centrifugal fan, comprising:
a housing, having an inlet opening;
a driving mechanism mounted in the housing;
a centrifugal impeller, driven by the driving mechanism, a flow channel is defined between the centrifugal impeller and the housing, the centrifugal impeller comprising:
a hub; and
multiple blades, each of the multiple blades secured to the hub at one end and having at least one vertical convex strip at an opposite end, when the centrifugal impeller rotates, airflow is sucked axially into the housing through the inlet opening, and moves along each of the multiple blades, wherein the vertical convex strip at each of the multiple blades disturbs the airflow across thereof and reduces narrow-band noises.
2. The centrifugal fan of claim 1 , wherein the driving mechanism is a motor.
3. A centrifugal fan, comprising:
a housing, having an inlet opening;
a driving mechanism, mounted in the housing;
a centrifugal impeller, driven by the driving mechanism, a flow channel is defined between the centrifugal impeller and the housing, the centrifugal impeller comprising:
a hub; and
multiple blades, each of the multiple blades secured to the hub at one end and having at least one vertical concave strip at an opposite end, when the centrifugal impeller rotates, airflow is sucked axially into the housing through the inlet opening, and moves along each of the multiple blades, wherein the vertical concave strip at each of the multiple blades disturbs the airflow across thereof and reduces narrow-band noise.
4. The centrifugal fan of claim 3 , wherein the driving mechanism is a motor.
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
TW095114589A TW200741106A (en) | 2006-04-24 | 2006-04-24 | Centrifugal fan |
TW95114589 | 2006-04-24 |
Publications (1)
Publication Number | Publication Date |
---|---|
US20070248459A1 true US20070248459A1 (en) | 2007-10-25 |
Family
ID=38619627
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US11/477,371 Abandoned US20070248459A1 (en) | 2006-04-24 | 2006-06-30 | Centrifugal fan |
Country Status (2)
Country | Link |
---|---|
US (1) | US20070248459A1 (en) |
TW (1) | TW200741106A (en) |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20100142146A1 (en) * | 2008-12-07 | 2010-06-10 | Furui Precise Component (Kunshan) Co., Ltd. | Centrifugal fan and electronic device using same |
CN102536850A (en) * | 2010-12-14 | 2012-07-04 | 台达电子工业股份有限公司 | Centrifugal fan |
US20190107115A1 (en) * | 2017-10-10 | 2019-04-11 | Inventec (Pudong) Technology Corporation | Fan module |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2035479A (en) * | 1935-05-09 | 1936-03-31 | Fed Merchandise Company | Fan |
US2054144A (en) * | 1934-07-19 | 1936-09-15 | Gen Motors Corp | Refrigerating apparatus |
US2965180A (en) * | 1954-12-20 | 1960-12-20 | American Radiator & Standard | Propeller fan wheel |
-
2006
- 2006-04-24 TW TW095114589A patent/TW200741106A/en unknown
- 2006-06-30 US US11/477,371 patent/US20070248459A1/en not_active Abandoned
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2054144A (en) * | 1934-07-19 | 1936-09-15 | Gen Motors Corp | Refrigerating apparatus |
US2035479A (en) * | 1935-05-09 | 1936-03-31 | Fed Merchandise Company | Fan |
US2965180A (en) * | 1954-12-20 | 1960-12-20 | American Radiator & Standard | Propeller fan wheel |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20100142146A1 (en) * | 2008-12-07 | 2010-06-10 | Furui Precise Component (Kunshan) Co., Ltd. | Centrifugal fan and electronic device using same |
US8011878B2 (en) * | 2008-12-07 | 2011-09-06 | Furui Precise Component (Kunshan) Co., Ltd. | Centrifugal fan and electronic device using same |
CN102536850A (en) * | 2010-12-14 | 2012-07-04 | 台达电子工业股份有限公司 | Centrifugal fan |
US20190107115A1 (en) * | 2017-10-10 | 2019-04-11 | Inventec (Pudong) Technology Corporation | Fan module |
US10746190B2 (en) * | 2017-10-10 | 2020-08-18 | Inventec (Pudong) Technology Corporation | Fan module |
Also Published As
Publication number | Publication date |
---|---|
TW200741106A (en) | 2007-11-01 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US9062681B2 (en) | Fan device and vane thereof | |
US8251642B2 (en) | Centrifugal fan | |
US8231331B2 (en) | Reduction of flow-induced noise in a centrifugal blower | |
US20050276684A1 (en) | Centrifugal fan with resonant silencer | |
US8210795B2 (en) | Flow-guiding device and fan assembly | |
US7618236B2 (en) | Fan and fan housing with toothed-type connecting elements | |
US8961124B2 (en) | Axial fan | |
US8100664B2 (en) | Impeller for a cooling fan | |
US20150016061A1 (en) | Centrifugal fan module and electronic device using the centrifugal fan module | |
US20090196744A1 (en) | Fan and impeller thereof | |
US8011878B2 (en) | Centrifugal fan and electronic device using same | |
KR101392784B1 (en) | centrifugal fan | |
US20060045774A1 (en) | Fans and fan frames | |
US8075276B2 (en) | Impeller and cooling fan incorporating the same | |
US9523375B2 (en) | Fan blade structure and centrifugal fan using the same | |
JP4621980B2 (en) | Fan motor | |
JP2001271791A (en) | Multiblade fan | |
JP5586659B2 (en) | Centrifugal blower | |
US20070065279A1 (en) | Blade structure for a radial airflow fan | |
JP2004332674A (en) | Axial fan | |
TW201344062A (en) | Axial flow fan | |
US20060182628A1 (en) | Blowing device | |
US7959413B2 (en) | Fan and impeller thereof | |
US20200182258A1 (en) | Blade and fan structure | |
US20070248459A1 (en) | Centrifugal fan |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AS | Assignment |
Owner name: QUANTA COMPUTER INC., TAIWAN Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:TSENG, CHUN-FA;HUANG, YU-NIEN;YU, SHUN-TA;AND OTHERS;REEL/FRAME:018027/0941 Effective date: 20060614 |
|
STCB | Information on status: application discontinuation |
Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION |