EP1422425B1 - Axial-flow fan - Google Patents

Axial-flow fan Download PDF

Info

Publication number
EP1422425B1
EP1422425B1 EP03016732A EP03016732A EP1422425B1 EP 1422425 B1 EP1422425 B1 EP 1422425B1 EP 03016732 A EP03016732 A EP 03016732A EP 03016732 A EP03016732 A EP 03016732A EP 1422425 B1 EP1422425 B1 EP 1422425B1
Authority
EP
European Patent Office
Prior art keywords
blade
protuberance
axial
flow fan
hub
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.)
Expired - Fee Related
Application number
EP03016732A
Other languages
German (de)
English (en)
French (fr)
Other versions
EP1422425A2 (en
EP1422425A3 (en
Inventor
Sim Won Chin
Moon Kee Chung
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
LG Electronics Inc
Original Assignee
LG Electronics Inc
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by LG Electronics Inc filed Critical LG Electronics Inc
Publication of EP1422425A2 publication Critical patent/EP1422425A2/en
Publication of EP1422425A3 publication Critical patent/EP1422425A3/en
Application granted granted Critical
Publication of EP1422425B1 publication Critical patent/EP1422425B1/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

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
    • F04D29/32—Rotors specially for elastic fluids for axial flow pumps
    • F04D29/38—Blades
    • F04D29/384—Blades characterised by form
    • 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
    • F04D29/32—Rotors specially for elastic fluids for axial flow pumps
    • F04D29/38—Blades
    • 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
    • F04D29/661—Combating cavitation, whirls, noise, vibration or the like; Balancing especially adapted for elastic fluid pumps
    • F04D29/667—Combating cavitation, whirls, noise, vibration or the like; Balancing especially adapted for elastic fluid pumps by influencing the flow pattern, e.g. suppression of turbulence

Definitions

  • the present invention relates to an axial-flow fan, which reduces the difference of pressure between a positive pressure side and a negative pressure side at the blade tip of each of blades, thereby preventing the occurrence of a vortex stream and subsequently reducing noise.
  • the present invention relates to an axial-flow fan as specified in the preamble of claim 1.
  • Such a fan is known from EP-A-0 992 693 .
  • an axial-flow fan is an apparatus which is connected to a rotary shaft of a motor, and sucks a fluid at its one side and then discharges the fluid at its opposite side in the centrifugal direction when a driving force of the motor is transmitted to the axial-flow fan via the rotary shaft.
  • the axial-flow fan has been widely applied in electrical appliances such as an air conditioner, a refrigerator, a microwave oven, etc.
  • the conventional axial-flow fan comprises a hub 2 connected to a rotary shaft (not shown) of a motor, and a plurality of blades 4 positioned on the outer circumference of the hub 2 and spaced from each other by a designated interval, thereby blowing air in the centrifugal direction.
  • the air When the axial-flow fan is rotated, the air is propelled from the rear side of the axial-flow fan to the front side of the axial-flow fan. Since the air flows along the front side of the blade 4, relatively higher pressure of the air is applied to the front side of the blade 4, and relatively lower pressure of the air is applied to the rear side of the blade 4.
  • the front and rear sides of the blade 4 are referred to as a positive pressure side 4a and a negative pressure side 4b, respectively.
  • a vortex stream occurs at a tip blade 4c, i.e., a circumferential surface of the blade 4.
  • BVI Blade Vortex Interaction
  • the present invention has been made in view of the above problems, and it is an object of the present invention to provide an axial-flow fan comprising blades having improved shapes so as to reduce the difference of pressure between positive pressure sides and negative pressure sides at tips of the blades when the fan is operated, thereby reducing the occurrence of a vortex stream.
  • each blade may have a designated rake angle.
  • the protuberance may be located at a part of the section from a position of "0.3” to a position of "1" of a distance from a blade hub to a blade tip.
  • the protuberance may be located throughout the section from a position of "0.3” to a position of "1" of a distance from a blade hub to a blade tip.
  • the protuberance may be formed on the positive pressure side so as to have a convex-shaped structure when viewed from the positive pressure side.
  • the peak of the protuberance may be positioned close to the blade tip, the peak of the protuberance may be located between a position of "0.7” and a position of "0.8" of the distance from the blade hub to the blade tip.
  • leading and trailing edges of the protuberance may be located on a line obtained by connecting a blade hub and a blade tip.
  • an axial-flow fan of the present invention comprises a hub 52, a plurality of blades 54, and protuberances 56.
  • Each blade 54 is formed with one of the protuberances 56.
  • the hub 52 is formed as a cylinder with the uniform diameter at a front side 52a and a rear side 52b, and guides air to centrifugally flow along the circumference of the hub 52.
  • a rotary shaft of a motor is fit into the center of the hub 52.
  • the blades 54 are positioned on the outer circumference of the hub 52 and circumferentially spaced from each other by a designated interval so as to allow air to flow in the centrifugal direction.
  • the protuberance 56 is formed on a designated part of each of the blades 54 so as to suppress a vortex of air flowing along the blades 54.
  • a front edge of the blade 54 is referred to as a leading edge 54a, and a rear edge of the blade 54 is referred to as a trailing edge 54b.
  • a circumferential ridge obtained by interconnecting the tips of the leading edge 54a and the trailing edge 54b is referred to as a blade tip 54c.
  • the blade tip 54c from the leading edge 54a to the trailing edge 54b has a predetermined curvature so that the leading edge 54a is located on the front side 52a of the hub 52 and the trailing edge 54b is located on the rear side 52b of the hub 52.
  • the front side of the blade 54 to which high pressure of the introduced air is applied is referred to as a positive pressure side 54d
  • the rear side of the blade 54 is referred to as a negative pressure side 54e.
  • the above-described blade 54 has a designated rake angle ( ⁇ ) .
  • the rake angle ( ⁇ ) of the blade 54 is an angle at which the blade 54 is tilted toward the rear side 52b of the hub 52. More specifically, the rake angle ( ⁇ ) of the blade 54 is an angle between a Y-axis passing through the center of the hub 52 and a cross-section of the blade 54 taken along a line obtained by connecting a blade hub 54f and the blade tip 54c.
  • a rake base line (L) the line obtained by connecting the blade hub 54f and the blade tip 54c is referred to as a rake base line (L).
  • the protuberance 56 is curved so as to be protruded from the blade tip 54c toward the positive pressure side 54d. As shown in Fig. 5 , in case that the distance from the blade hub 54f to the blade tip 54c is predetermined as "1", the protuberance 56 is located throughout the section from the position of "0.3" to the position of "1".
  • the protuberance 56 includes a front portion 56a and a rear portion 56b.
  • the protuberance 56 is centered on the peak (P) of the protuberance 56, i.e., the most protruding portion of the protuberance 56, such that the front portion 56a is located close to the blade hub 54f and tilted upward in the radial direction of the blade 54 toward on the peak (P) of the protuberance 56, and the rear portion 56b is located close to the blade tip 54c and tilted downward in the radial direction of the blade 54 from the peak (P) of the protuberance 56.
  • the peak (P) is positioned closer to the blade tip 54c than to the blade hub 54f. That is, the peak (P) is located between the position of "0.7” and the position of "0.8” of the distance from the blade hub 54f to the blade tip 54c, and has from the rake base line (L) a height of approximately 5 ⁇ 10% of the distance between the blade hub 54f and the blade tip 54c.
  • the rear portion 56b of the protuberance 56 is formed throughout a radial distance shorter than that of the front portion 56a connected to the rear portion 56b. Accordingly, the rear portion 56b has a steeper degree of slope than that of the front portion 56a, thereby allowing air passing through the peak (P) along the blade 54 to effectively flow at the blade tip 54c.
  • a leading edge 56L of the protuberance 56 is located at the position of "0.3" of the distance from the blade hub 54f to the blade tip 54c, and a trailing edge 56T of the protuberance 56 is located at the blade tip 54c.
  • the leading and trailing edges 56L and 56T of the protuberance 56 are positioned on the rake base line (L).
  • the protuberance 56 may located at a part of the section from the position of "0.3” to the position of "1" of the distance from the blade hub 54f and the blade tip 54c.
  • the axial-flow fan fixed to the rotary shaft of the motor is rotated. Air is introduced into the axial-flow fan via the front side 52a of the hub 52, and then centrifugally discharged from the axial-flow fan via the rear side 52b of the hub 52.
  • the air circumferentially flows from the leading edges 54a of the blades 54 to the trailing edges 54b of the blades 54, and simultaneously, radially flows from the blade hubs 54f to the blade tips 54c of the blades 54.
  • the introduced air is divided into two portions by the leading edge 54a of the blade 54, and the divided two portions of the air are respectively fed to the positive pressure side 54d and the negative pressure side 54e of the blade in the circumferential direction of the blade. High pressure of the air is applied to the positive pressure side 54d, and low pressure of the air is applied to the negative pressure side 54e.
  • the air flowing between the blade hub 54f and the peak (P) of the protuberance 56 is first introduced along the front end of the leading edge 54a, and then discharged from the front end the trailing edge 54b along the front portion 56a of the protuberance 56 of the positive pressure side 54d and simultaneously flows along the front portion 56a of the protuberance 56 in the radial direction of the blade 54 by the centrifugal force. Since the front portion 56a of the protuberance 56 is tilted upward in the radial direction of the blade 54, the amount of airflow blowing toward the blade tip 54c along the positive pressure side 54d is reduced. Accordingly, the pressure of airflow on the positive pressure side 54d at the blade tip 54c is lowered.
  • the air flowing between the peak (P) of the protuberance 56 and the blade tip 54c is first introduced along the rear end of the leading edge 54a, and then discharged from the rear end of the trailing edge 54b along the rear portion 56b of the protuberance 56 of the positive pressure side 54d and simultaneously flows along the rear portion 56b of the protuberance 56 in the radial direction of the blade 54 by the centrifugal force. Since the rear portion 56b of the protuberance 56 is tilted downward in the radial direction of the blade, the air effectively flows between the positive pressure side 54d and the negative pressure side 54e at the blade tip 54c along the rear portion 56b of the protuberance 56.
  • the pressure of an airflow applied to the positive pressure side 54d at the blade tip 54c is relatively lowered, and the restoration to the static pressure of air flowing from the positive pressure side 54d to the negative pressure side 54e is slowly performed, thereby reducing noise caused by the collision of the air with the peripheral structures.
  • the axial-flow fan of the present invention comprising the protuberances 56 formed at designated positions of the blades 54 has the same performance as that of the conventional axial-flow fan in terms of the amount of airflow and the power consumption relative to the number of rotations of the axial-flow fan.
  • the axial-flow fan of the present invention compared to the conventional axial-flow fan, the axial-flow fan of the present invention generates reduced noise relative to the number of rotations of the axial-flow fan.
  • the axial-flow fan of the present invention compared to the conventional axial-flow fan, the axial-flow fan of the present invention generates reduced isolated noise caused by the collision of the vortex occurring at the blade tip 54c with peripheral structures, relative to a variation in frequency.
  • the axial-flow fan of the present invention having the above-described anti-noise structure improves the noise reduction ratio.
  • the axial-flow fan of the present invention has several advantages, as follows.
  • the axial-flow fan of the present invention reduces the amount and the pressure of airflow flowing along the positive pressure sides at the blade tips, thereby reducing the difference of pressure between the positive pressure sides and the negative pressure sides, diminishing the occurrence of a vortex stream and the noise generated thereby.
  • the axial-flow fan of the present invention lowers the pressure of airflow applied on the positive pressure sides at the blade tips, thereby slowing down the restoration to the static pressure of air flowing from the positive pressure sides to the negative pressure sides and reducing noise caused by the collision of the air with the peripheral structures.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Structures Of Non-Positive Displacement Pumps (AREA)
EP03016732A 2002-11-19 2003-07-22 Axial-flow fan Expired - Fee Related EP1422425B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
KR2002071993 2002-11-19
KR10-2002-0071993A KR100484824B1 (ko) 2002-11-19 2002-11-19 축류팬

Publications (3)

Publication Number Publication Date
EP1422425A2 EP1422425A2 (en) 2004-05-26
EP1422425A3 EP1422425A3 (en) 2005-01-19
EP1422425B1 true EP1422425B1 (en) 2008-12-03

Family

ID=32226319

Family Applications (1)

Application Number Title Priority Date Filing Date
EP03016732A Expired - Fee Related EP1422425B1 (en) 2002-11-19 2003-07-22 Axial-flow fan

Country Status (4)

Country Link
EP (1) EP1422425B1 (ja)
JP (1) JP2004169682A (ja)
KR (1) KR100484824B1 (ja)
ES (1) ES2316676T3 (ja)

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR100547328B1 (ko) * 2003-09-05 2006-01-26 엘지전자 주식회사 에어컨 실외기의 축류팬
EP2212562B2 (en) * 2007-10-25 2017-05-03 LG Electronics Inc. Fan
JP5425678B2 (ja) * 2010-03-24 2014-02-26 三洋電機株式会社 軸流ファン
KR20170032791A (ko) 2015-09-15 2017-03-23 김서연 접이식 방석 의자
JP6428833B2 (ja) * 2017-04-14 2018-11-28 ダイキン工業株式会社 プロペラファン

Family Cites Families (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB401625A (en) * 1932-07-30 1933-11-16 British Thomson Houston Co Ltd Improvements in and relating to rotary fans
JP2809442B2 (ja) * 1989-08-30 1998-10-08 カルソニック株式会社 自動車の熱交換器用冷却ファン
US4930990A (en) * 1989-09-15 1990-06-05 Siemens-Bendix Automotive Electronics Limited Quiet clutch fan blade
JP2765219B2 (ja) * 1990-11-06 1998-06-11 株式会社デンソー 送風用ファン
JP3203994B2 (ja) * 1994-10-31 2001-09-04 三菱電機株式会社 軸流送風機
JP3346179B2 (ja) * 1996-08-02 2002-11-18 ダイキン工業株式会社 送風機用羽根車
JPH1144432A (ja) * 1997-07-24 1999-02-16 Hitachi Ltd 空気調和機
KR19990020857A (ko) * 1997-08-30 1999-03-25 양재신 송풍성이 양호한 저소음 냉각 팬
JP3204208B2 (ja) * 1998-04-14 2001-09-04 松下電器産業株式会社 斜流送風機羽根車
IT1303113B1 (it) * 1998-10-08 2000-10-30 Gate Spa Ventola assiale, particolarmente per il raffreddamento di unoscambiatore di calore in un autoveicolo.
US6447251B1 (en) * 2000-04-21 2002-09-10 Revcor, Inc. Fan blade
KR100421884B1 (ko) * 2001-02-13 2004-03-09 엘지전자 주식회사 축류팬
JP2002250298A (ja) * 2001-02-23 2002-09-06 Mitsubishi Heavy Ind Ltd プロペラファン

Also Published As

Publication number Publication date
EP1422425A2 (en) 2004-05-26
JP2004169682A (ja) 2004-06-17
EP1422425A3 (en) 2005-01-19
ES2316676T3 (es) 2009-04-16
KR20040043623A (ko) 2004-05-24
KR100484824B1 (ko) 2005-04-22

Similar Documents

Publication Publication Date Title
US6027307A (en) Fan and shroud assembly adopting the fan
EP1862675B1 (en) Axial fan assembly
EP1208303B1 (en) Cooling fan
EP1484510A1 (en) Fan
US6024537A (en) Axial flow fan
US8167562B2 (en) Centrifugal fan and blower having the same
JP4014887B2 (ja) 遠心ファンおよびその遠心ファンを備えた加熱調理器
JP5145188B2 (ja) 多翼遠心ファンおよびそれを用いた空気調和機
JP3677214B2 (ja) 軸流ファン
EP1422425B1 (en) Axial-flow fan
US6695584B2 (en) Turbo fan
JP3366265B2 (ja) 遠心送風機
JP2000018194A (ja) 送風機用羽根車
EP1326482A2 (en) Cooling fan for microwave oven
EP1411248B1 (en) Impeller for centrifugal fan and centrifugal fan equipped with the same
KR100422704B1 (ko) 보조 임펠러가 구비된 축류팬
CN116249838B (zh) 螺旋桨式风扇
KR100416779B1 (ko) 터보 팬
CN220705996U (zh) 电机散热风扇
KR100347914B1 (ko) 터보팬
KR100416777B1 (ko) 터보팬
KR100507324B1 (ko) 공기조화기용 터보팬
KR19990000953A (ko) 축류/사류팬 구조
JP4736252B2 (ja) 多翼送風機の羽根車及びそれを備えた多翼送風機
KR19990056525A (ko) 송풍기 유니트

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

17P Request for examination filed

Effective date: 20030722

AK Designated contracting states

Kind code of ref document: A2

Designated state(s): AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IT LI LU MC NL PT RO SE SI SK TR

AX Request for extension of the european patent

Extension state: AL LT LV MK

PUAL Search report despatched

Free format text: ORIGINAL CODE: 0009013

AK Designated contracting states

Kind code of ref document: A3

Designated state(s): AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IT LI LU MC NL PT RO SE SI SK TR

AX Request for extension of the european patent

Extension state: AL LT LV MK

AKX Designation fees paid

Designated state(s): ES FR IT

REG Reference to a national code

Ref country code: DE

Ref legal event code: 8566

17Q First examination report despatched

Effective date: 20060620

RIN1 Information on inventor provided before grant (corrected)

Inventor name: CHIN, SIM WON

Inventor name: CHUNG, MOON KEE

GRAP Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOSNIGR1

GRAS Grant fee paid

Free format text: ORIGINAL CODE: EPIDOSNIGR3

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): ES FR IT

REG Reference to a national code

Ref country code: ES

Ref legal event code: FG2A

Ref document number: 2316676

Country of ref document: ES

Kind code of ref document: T3

PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

26N No opposition filed

Effective date: 20090904

REG Reference to a national code

Ref country code: FR

Ref legal event code: PLFP

Year of fee payment: 14

REG Reference to a national code

Ref country code: FR

Ref legal event code: PLFP

Year of fee payment: 15

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: FR

Payment date: 20170608

Year of fee payment: 15

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: IT

Payment date: 20170712

Year of fee payment: 15

Ref country code: ES

Payment date: 20170814

Year of fee payment: 15

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: FR

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20180731

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: IT

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20180722

REG Reference to a national code

Ref country code: ES

Ref legal event code: FD2A

Effective date: 20190917

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: ES

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20180723