EP2535594A1 - Centrifugal blower - Google Patents

Centrifugal blower Download PDF

Info

Publication number
EP2535594A1
EP2535594A1 EP11742035A EP11742035A EP2535594A1 EP 2535594 A1 EP2535594 A1 EP 2535594A1 EP 11742035 A EP11742035 A EP 11742035A EP 11742035 A EP11742035 A EP 11742035A EP 2535594 A1 EP2535594 A1 EP 2535594A1
Authority
EP
European Patent Office
Prior art keywords
bell mouth
outer peripheral
rear side
front side
peripheral surface
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.)
Withdrawn
Application number
EP11742035A
Other languages
German (de)
English (en)
French (fr)
Inventor
Takanori Nagae
Shimei Tei
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.)
Daikin Industries Ltd
Original Assignee
Daikin Industries Ltd
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 Daikin Industries Ltd filed Critical Daikin Industries Ltd
Publication of EP2535594A1 publication Critical patent/EP2535594A1/en
Withdrawn legal-status Critical Current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
    • F04D29/40—Casings; Connections of working fluid
    • F04D29/42—Casings; Connections of working fluid for radial or helico-centrifugal pumps
    • F04D29/44—Fluid-guiding means, e.g. diffusers
    • F04D29/441—Fluid-guiding means, e.g. diffusers especially adapted for elastic fluid pumps
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04D—NON-POSITIVE-DISPLACEMENT PUMPS
    • F04D25/00—Pumping installations or systems
    • F04D25/02—Units comprising pumps and their driving means
    • F04D25/08—Units comprising pumps and their driving means the working fluid being air, e.g. for ventilation
    • 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
    • F04D29/002—Details, component parts, or accessories especially adapted for elastic fluid pumps
    • 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
    • F04D29/08—Sealings
    • F04D29/16—Sealings between pressure and suction sides
    • F04D29/161—Sealings between pressure and suction sides especially adapted for elastic fluid pumps
    • F04D29/162—Sealings between pressure and suction sides especially adapted for elastic fluid pumps of a centrifugal flow wheel
    • 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
    • F04D29/40—Casings; Connections of working fluid
    • F04D29/42—Casings; Connections of working fluid for radial or helico-centrifugal pumps
    • F04D29/4206—Casings; Connections of working fluid for radial or helico-centrifugal pumps especially adapted for elastic fluid pumps
    • F04D29/4213—Casings; Connections of working fluid for radial or helico-centrifugal pumps especially adapted for elastic fluid pumps suction ports
    • 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
    • F04D29/663—Sound attenuation
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
    • F05D—INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
    • F05D2210/00—Working fluids
    • F05D2210/10—Kind or type
    • F05D2210/12—Kind or type gaseous, i.e. compressible
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
    • F05D—INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
    • F05D2250/00—Geometry
    • F05D2250/50—Inlet or outlet
    • F05D2250/51—Inlet
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S415/00—Rotary kinetic fluid motors or pumps
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S417/00—Pumps

Definitions

  • the present invention relates to a centrifugal fan for use in, for example, an indoor unit of an air conditioner.
  • a centrifugal fan for example, has conventionally been used as a fan of an indoor unit of an air conditioner.
  • a fan motor of the centrifugal fan is driven to rotate an impeller thereof, whereby air is suctioned from a suction port of the indoor unit into the indoor unit.
  • the suctioned air is guided to an air suction port of a shroud by a bell mouth (a flow of air guided to the air suction port by the bell mouth is referred to as "main flow" hereinafter).
  • the air of the main flow is sent to the outside of a radial direction by a plurality of blades arranged between a hub and the shroud in a circumferential direction. Most of the air is blown into a room through an outlet port of the indoor unit, but some of the air flows backward toward the bell mouth through a space outside an outer peripheral surface of the shroud in the indoor unit and merges with the main flow again through a gap between the bell mouth and the shroud (this flow in which the air flows back and merges with the main flow through the gap as described above is referred to as "leakage flow" hereinafter).
  • the leakage flow As a result of the occurrence of the leakage flow in which a part of the main flow diverges, the amount of air to be blown into the room decreases by the amount of the diverging air, reducing the fan efficiency of the centrifugal fan.
  • Patent Document 1 discloses a centrifugal fan in which a number of grooves are provided on an outer surface of a bell mouth (fan guide) in order to prevent reduction in fan efficiency.
  • this centrifugal fan the leakage flow that flows back toward the bell mouth through a space outside an outer peripheral surface of a shroud is introduced to a gap between the bell mouth and the shroud via the grooves (see paragraphs 0024 and 0052 and Figs. 5 and 6 of Patent Document 1).
  • Patent Document 1 describes that reduction of the blowing performance thereof caused by a fluctuation of the leakage flow can be prevented by the assistance of the grooves guiding the leakage flow to obtain a stable air flow.
  • the present invention was contrived in view of the circumstances described above, and an object thereof is to provide a centrifugal fan capable of preventing reduction in the fan efficiency thereof that is caused by the leakage flow.
  • a centrifugal fan of the present invention has an impeller (23) and a bell mouth (25).
  • the impeller (23) includes a hub (15) that is fixed to a rotating shaft (13) of a fan motor (11), a shroud (19) that has an air suction port (19a) opened in a circular shape around a central axis of the rotating shaft (13) and is disposed to face the hub (15) on a front side (F) in an axial direction (A) of the rotating shaft (13), and a plurality of blades (21) that are arranged between the hub (15) and the shroud (19) along a circumferential direction of the air suction port (19a).
  • the bell mouth (25) is disposed so as to face the shroud (19) on the front side (F) in the axial direction (A) and which has a part, on a rear side (R), inserted into the shroud (19) through the air suction port (19a) while a predetermined gap is kept between the part and a peripheral rim part (19e) of the air suction port (19a).
  • the bell mouth (25) guides air suctioned from the front side (F) to the rear side (R) in the axial direction (A), to the air suction port (19a) of the shroud (19).
  • the bell mouth (25) has a plurality of wall parts (27) provided on an outer peripheral surface (25s) of the bell mouth (25).
  • the wall parts (27) are arranged at predetermined intervals on the outer peripheral surface (25s) in a circumferential direction of the outer peripheral surface (25s). Each of the wall parts (27) extends along the outer peripheral surface (25s) from the front side (F) to the rear side (R) in the axial direction (A) so as to be substantially parallel to the axial direction (A) and to a radial direction of the bell mouth (25).
  • a centrifugal fan 51 according to an embodiment of the present invention and an indoor unit 31 equipped with the centrifugal fan 51 are described hereinafter with reference to the drawings.
  • the indoor unit 31 is a ceiling-embedded type cassette indoor unit.
  • This indoor unit 31 has a substantially rectangular parallelepiped housing 33 embedded in an opening provided on a ceiling, and a decorative panel 47 attached to a lower part of the housing 33.
  • the decorative panel 47 is slightly larger than the housing 33 as viewed in planar view and is exposed inside a room while covering the opening of the ceiling.
  • the decorative panel 47 has a rectangular suction grill 39 provided in a central part of the decorative panel 47 and four elongated rectangular outlet ports 37 provided along sides of the suction grill 39.
  • the indoor unit 31 has, in its housing 33, the centrifugal fan (turbofan) 51, a fan motor 11, a heat exchanger 43, a drain pan 45, an air filter 41, and the like.
  • the centrifugal fan 51 includes an impeller 23 and a bell mouth 25.
  • the fan motor 11 is fixed at substantially the center of a top panel of the housing 33. A rotating shaft 13 of the fan motor 11 extends downward.
  • the heat exchanger 43 is thin and flat.
  • the heat exchanger 43 stands upward from the dish-like drain pan 45 provided along a lower end part of the heat exchanger 43 and is disposed in a manner as to surround the impeller 23.
  • the drain pan 45 is for storing water droplets generated in the heat exchanger 43. The stored water is discharged through a drainage path, which is not shown.
  • the air filter 41 is large enough to cover an inlet port of the bell mouth 25 and is provided along the suction grill 39 between the bell mouth 25 and the suction grill 39. When air is suctioned into the housing 33 through the suction grill 39 and passes through the air filter 41, the air filter 41 captures dust in the air.
  • the impeller 23 includes a hub 15, a shroud 19, and a plurality of blades 21.
  • the hub 15 is fixed to a lower end part of the rotating shaft 13 of the fan motor 11.
  • the hub 15 is formed in a circular shape around a central axis of the rotating shaft 13 as viewed in planar view.
  • the shroud 19 is disposed so as to face the hub 15 on a front side F in relation to the hub 15 in the axial direction A of the rotating shaft 13.
  • the shroud 19 has an air suction port 19a opened in a circular shape around the central axis of the rotating shaft 13.
  • An outer diameter of the shroud 19 increases from the front side F toward a rear side R.
  • the plurality of blades 21 are arranged along a circumferential direction of the air suction port 19a at predetermined intervals between the hub 15 and the shroud 19. An end part on the front side F of each blade 21 is joined to an inner surface of the shroud 19. An end part on the rear side R of each blade 21 is joined to the hub 15.
  • Each of the blades 21 is a backward curved blade inclined in a direction opposite (backward) to a rotation direction with respect to a radial direction of the hub 15.
  • the bell mouth 25 is disposed so as to face the shroud 19 on the front side F in relation to the shroud 19 in the axial direction A.
  • the bell mouth 25 includes a bell mouth main body 251 and a flange part 252 that projects from a peripheral rim on the front side F of the bell mouth main body 251 to a periphery of the bell mouth main body 251.
  • the bell mouth 251 has a through-hole 25a provided in a front-back direction.
  • An outer peripheral surface 25s of the bell mouth main body 251 is curved in a manner that an outer diameter thereof becomes small gradually from the front side F toward the rear side R.
  • a part on the rear side R of the bell mouth main body 251 is inserted into the shroud 19 through the air suction port 19a while keeping a predetermined gap between the part and a peripheral rim part 19e of the air suction port 19a.
  • the bell mouth 25 can guide the air to the air suction port 19a of the shroud 19, the air being suctioned from the front side F toward the rear side R through the through-hole 25a.
  • the bell mouth 25 has a plurality of wall parts 27 that are arranged on the outer peripheral surface 25s of the bell mouth main body 251 in a circumferential direction at predetermined intervals.
  • the wall parts 27 are provided on the outer peripheral surface 25s of the bell mouth 25.
  • Each of the wall parts 27 extends along the outer peripheral surface 25s from the front side F toward the rear side R so as to be substantially parallel to the axial direction A and to a radial direction of the bell mouth 25.
  • the bell mouth 25 has a plurality of airflow paths 253, each of which is surrounded by adjacent wall parts 27 and the outer peripheral surface 25s. These airflow paths 253 are directed along the axial direction A. Although the both sides and the bottom of each of these airflow paths 253 are surrounded by the adjacent wall parts 27 and the outer peripheral surface 25s of the bell mouth 25, an entrance and exist of the airflow path 253 for a leakage flow are opened and not blocked. The leakage flow, therefore, is guided reliably to the entrance of the airflow path 253 between the wall parts 27 and then through the inside of the airflow path 253 from the front side F toward the rear side R.
  • the height of each of the wall parts 27 with respect to the outer peripheral surface 25s gradually increases from an end part 27r thereof on the rear side R toward an end part 27f on the front side F.
  • a height Hf of the end part 27f on the front side F of each wall part 27 is greater than a height Hr of the end part 27r on the rear side R.
  • the height Hr can be approximately 1 mm to 10 mm, and the height Hf can be approximately 3 mm to 20 mm, but the height Hr and the height Hf are not particularly limited to these ranges.
  • each wall part 27 in each wall part 27 the end part 27r on the rear side R is an inclined surface inclined with respect to the axial direction A.
  • the height of this inclined surface with respect to the outer peripheral surface 25s decreases gradually from the front side F toward the rear side R.
  • the peripheral rim part 19e of the air suction port 19a is an inclined surface inclined with respect to the axial direction A, as shown in Fig. 8 .
  • the inclined surface of the peripheral rim part 19e is provided so as to face the inclined surface of the end part 27r on the rear side R of each wall part 27.
  • a tip end of the end part 27r on the rear side R of each wall part 27 is provided in the position (substantially at the same level) so as to almost face radially a tip end of the peripheral rim part 19e, which is an end part on the front side F of the shroud 19.
  • the inclined surface of the peripheral rim part 19e is inclined in a manner that a part thereof on the rear side R is positioned more inward in the radial direction than a part on the front side F.
  • the inclined surface of the end part 27r of each wall part 27 is inclined in a manner that a part thereof on the rear side R is positioned more inward in the radial direction than a part on the front side F. Because the end parts of the peripheral rim part 19e and of each wall part 27 are configured by the inclined surfaces, the end part 27r on the rear side R of each wall part 27 can be extended to the position facing the peripheral rim part 19e of the shroud 19 or to a position in the vicinity of this position.
  • the bell mouth 25 may be formed by integrally molding each wall part 27 with the bell mouth main body 251 by means of, for example, sheet-metal processing or resin molding processing, or may be formed by molding each wall part 27 separately from the bell mouth main body 251 and then joining each wall part 27 to the bell mouth main body 251.
  • Fig. 9 is a cross-sectional diagram showing a modification of the bell mouth 25.
  • This bell mouth 25, as with the bell mouth 25 shown in Fig. 5 has a plurality of wall parts 27 arranged on an outer peripheral surface of the bell mouth 25 in a circumferential direction at predetermined intervals.
  • the wall parts 27 are provided on the outer peripheral surface of the bell mouth 25.
  • Each of the wall parts 27 extends along the outer peripheral surface from the front side F toward the rear side R so as to be substantially parallel to the axial direction A and to the radial direction of the bell mouth 25.
  • This bell mouth 25 is formed by integrally molding each wall part 27 with a bell mouth main body by means of, for example, sheet-metal processing or resin molding processing.
  • a plurality of grooves 254 are formed on an inner surface of the bell mouth 25 so as to correspond to the plurality of wall parts 27.
  • the grooves 254 are arranged on the inner surface along the circumferential direction thereof at predetermined intervals.
  • Each of the grooves 254 extends along the inner surface from the front side F toward the rear side R so as to be substantially parallel to the axial direction A and to the radial direction of the bell mouth 25.
  • the thickness of the bell mouth 25 can be made substantially entirely constant. Molding the bell mouth 25 by means of, for example, resin molding processing can prevent the generation of shrinkage or other molding defects.
  • These grooves 254 play a role of guiding a main flow flowing through the through-hole 25a of the bell mouth 25.
  • a main flow S of air guided to the air suction port 19a of the shroud 19 by the bell mouth main body 251 of the bell mouth 25 flows mainly in a direction along the axial direction A of the rotating shaft 13 of the shroud 19, in the vicinity of the air suction port 19a.
  • a leakage flow M1 is affected by air that flows in a direction K of rotation of the shroud 19 when the shroud 19 rotates in this rotation direction K, as indicated by a dashed arrow M1. Therefore, the leakage flow M1 flows obliquely from the axial direction A to the rotation direction K. Therefore, when this leakage flow M1 merges with the main flow S, the main flow S is disturbed by the leakage flow M1, increasing the air flow noise and reducing the fan efficiency.
  • the leakage flow M is guided from the front side F to the rear side R along each airflow path 253 surrounded by the adjacent wall parts 27 and the outer peripheral surface 25S of the bell mouth main body 251 as indicated by a dashed-dotted arrow M, and then passes through a gap between the end part on the rear side R of the bell mouth main body 251 and the end part on the front side F of the shroud 19.
  • the direction of the leakage flow M passing through the gap is corrected to be more similar to the axial direction A than that of the conventional centrifugal fan is. This can prevent interference caused when the leakage flow M merges with the main flow S.
  • Fig. 10 is a graph showing a relationship between an air volume and air flow noise.
  • Fig. 11 is a graph showing a relationship between the air volume and a motor input.
  • the solid lines shown in Figs. 10 and 11 show the characteristics of the indoor unit 31 having the centrifugal fan 51 according to the present embodiment shown in Figs. 1 to 8 (example).
  • Dashed lines shown in Figs. 10 and 11 show the characteristics of the indoor unit 31 having a conventional bell mouth with no wall parts 27 (comparative example).
  • the data shown in Fig. 10 are measured by using the bell mouth 25 in which the bell mouth main body 251 is provided with the wall parts 27 that become tall gradually from the rear side R toward the front side F, with the height Hr on the rear side R being 3 mm and the height Hf on the front side F being 5 mm.
  • the data shown in Fig. 11 are measured by using the bell mouth 25 in which the bell mouth main body 251 is provided with the wall parts 27 that become tall gradually from the rear side R toward the front side F, with the height Hr on the rear side R being 6 mm and the height Hf on the front side F being 8 mm.
  • the air flow noise of the example is lower than that of the comparative example. Moreover, the effect of reducing the air flow noise increases as the air volume increases.
  • One vertical scale on the graph shown in Fig. 10 is 1 dBA.
  • the motor input of the example is lower than that of the comparative example.
  • the motor input that is required in the example to obtain the same air volume as the comparative example is lower than that of the comparative example.
  • the amount of leakage flow of the example is lower than that of the comparative example.
  • One vertical scale of the graph shown in Fig. 11 is 10 W.
  • the centrifugal fan of the present embodiment has an impeller and a bell mouth.
  • the impeller includes a hub fixed to a rotating shaft of a fan motor, a shroud that has an air suction port opened in a circular shape around a central axis of the rotating shaft and is disposed in relation to the hub so as to face the hub on a front side in an axial direction of the rotating shaft, and a plurality of blades that are arranged between the hub and the shroud along a circumferential direction of the air suction port.
  • the bell mouth is disposed in relation to the shroud so as to face the shroud on the front side in the axial direction and has a part thereof on a rear side inserted into the shroud through the air suction port while keeping a predetermined gap between the part and a peripheral rim part of the air suction port.
  • the bell mouth guides air suctioned from the front side to the rear side in the axial direction, to the air suction port of the shroud.
  • the bell mouth has a plurality of wall parts provided on an outer peripheral surface of the bell mouth.
  • the wall parts are arranged on the outer peripheral surface of the bell mouth in a circumferential direction at predetermined intervals. Each of the wall parts extends along the outer peripheral surface from the front side to the rear side in the axial direction so as to be substantially parallel to the axial direction and to a radial direction of the bell mouth.
  • the plurality of wall parts of the bell mouth can be resistances to the leakage flow, reducing the amount of leakage flow.
  • the direction of the leakage flow can be made similar to the direction of the main flow, preventing the main flow from being disturbed when the leakage flow merges with the main flow. As a result, a decrease in the fan efficiency can be prevented.
  • the air of the main flow that is guided to the air suction port of the shroud by the bell mouth mainly flows in a direction along the axial direction of the rotating shaft, in the vicinity of the air suction port.
  • the leakage flow is affected by the air that flows in the direction of rotation of the shroud, thereby flowing obliquely from the axial direction of the rotating shaft to this rotation direction.
  • the direction of the main flow is significantly different from the direction of the leakage flow. Therefore, when the leakage flow merges with the main flow, the main flow is disturbed by the leakage flow, causing a reduction in the fan efficiency.
  • each of the wall parts extends along the outer peripheral surface of the bell mouth from the front side to the rear side in the axial direction so as to be substantially parallel to the axial direction and to the radial direction.
  • each airflow path between the adjacent wall parts extends in the direction along the axial direction.
  • the airflow path configures a space whose sides and bottom are surrounded by the adjacent wall parts and the outer peripheral surface of the bell mouth. The entrance and exist of the airflow path for the leakage flow are opened and not blocked. The leakage flow, therefore, can reliably be let pass through the airflow path between the wall parts. Hence, an excellent effect of guiding the leakage flow can be obtained.
  • the direction of the leakage flow is corrected to the axial direction by the airflow path, further increasing the resistance to the air passing through the airflow path, more than when no wall parts are provided.
  • the amount of leakage flow diverging from the main flow can be reduced.
  • the direction of the leakage flow rectified by the airflow path becomes similar to the axial direction, which is the direction of the main flow. This can reduce the level of interference caused to the main flow by the leakage flow when the leakage flow merges with the main flow in the vicinity of the air suction port. As a result, a decrease in the fan efficiency caused by the leakage flow can be prevented.
  • a height of an end part on the front side of each wall part with respect to the outer peripheral surface be greater than a height of an end part on the rear side of each wall part with respect to the outer peripheral surface.
  • each wall part can catch a large amount of leakage flow at the tall end part on the rear side and guide the leakage flow to the airflow path, while preventing the short end part on the front side and the peripheral rim part of the air suction port of the shroud from coming into contact with each other at the short end part on the front side.
  • a height of each wall with respect to the outer peripheral surface may increase gradually from the end part on the rear side toward the end part on the front side.
  • the height of each wall part changes smoothly, making the flow of air smooth in the airflow path.
  • each wall part may be an inclined surface in which the height thereof with respect to the outer peripheral surface decreases gradually from the front side toward the rear side, and the peripheral rim part of the air suction port may be an inclined surface facing the inclined surface of each wall part.
  • each wall part can be extended to the vicinity of the shroud. This can prevent the wall parts and the shroud from coming into contact with each other when the shroud rotates.
  • the embodiment has described the example in which the height of each of the wall parts is increased gradually from the rear side toward the front side; however, the height may be increased in a stepwise manner from the rear side toward the front side.
  • the height of each wall part may be constant all the way from the rear side to the front side or reduced from the rear side toward the front side.
  • each wall part is the inclined surface in which the height thereof decreases gradually from the front side toward the rear side
  • the peripheral rim part of the air suction port is the inclined surface facing the inclined surface of each wall part.
  • the end part on the rear side of each wall part may not be an inclined surface but a surface perpendicular to the axial direction.
  • the peripheral rim part of the air suction port may be a surface perpendicular to the axial direction.
  • each wall part has described the example in which the tip end of the end part on the rear side of each wall part is provided in the position (substantially at the same level) so as to almost face radially the tip end of the peripheral rim part, which is the end part on the front side of the shroud.
  • the present invention is not limited thereto.
  • the end part on the rear side of each wall part may be provided in front of or behind the end part on the front side of the shroud.
  • the embodiment has described the example in which the centrifugal fan is used in an indoor unit of an air conditioner; however, the centrifugal fan can be applied to other uses.
EP11742035A 2010-02-10 2011-02-09 Centrifugal blower Withdrawn EP2535594A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2010027876A JP4844678B2 (ja) 2010-02-10 2010-02-10 遠心送風機
PCT/JP2011/000734 WO2011099286A1 (ja) 2010-02-10 2011-02-09 遠心送風機

Publications (1)

Publication Number Publication Date
EP2535594A1 true EP2535594A1 (en) 2012-12-19

Family

ID=44367572

Family Applications (1)

Application Number Title Priority Date Filing Date
EP11742035A Withdrawn EP2535594A1 (en) 2010-02-10 2011-02-09 Centrifugal blower

Country Status (8)

Country Link
US (1) US20120308370A1 (ja)
EP (1) EP2535594A1 (ja)
JP (1) JP4844678B2 (ja)
KR (1) KR20120123440A (ja)
CN (1) CN102753836A (ja)
AU (1) AU2011215464A1 (ja)
BR (1) BR112012020088A2 (ja)
WO (1) WO2011099286A1 (ja)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP3006840A1 (en) * 2014-10-10 2016-04-13 Fujitsu General Limited Ceiling-embedded air conditioner
US11566634B2 (en) 2018-10-31 2023-01-31 Carrier Corporation Arrangement of centrifugal impeller of a fan for reducing noise

Families Citing this family (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP5195983B2 (ja) * 2011-08-10 2013-05-15 ダイキン工業株式会社 遠心送風機
JP5522306B1 (ja) * 2012-12-21 2014-06-18 ダイキン工業株式会社 遠心ファン
KR102199376B1 (ko) 2013-07-12 2021-01-06 엘지전자 주식회사 원심 송풍기 및 이를 포함하는 공기 조화기
US10036400B2 (en) 2014-05-02 2018-07-31 Regal Beloit America, Inc. Centrifugal fan assembly and methods of assembling the same
JP2016132991A (ja) * 2015-01-15 2016-07-25 パナソニックＩｐマネジメント株式会社 送風装置
US9915267B2 (en) * 2015-06-08 2018-03-13 Air Distribution Technologies Ip, Llc Fan inlet recirculation guide vanes
CN107850318B (zh) * 2015-07-08 2020-06-26 日立江森自控空调有限公司 空调机的室内机
WO2018020894A1 (ja) * 2016-07-25 2018-02-01 株式会社Ｓｏｋｅｎ 遠心送風機
CN112236598B (zh) 2018-06-11 2022-12-16 开利公司 离心式风扇的叶轮-进气口接口和具有该接口的离心式风扇
CN111442378B (zh) * 2019-01-17 2021-09-21 青岛海尔空调器有限总公司 吊顶式空调室内机
KR20210115564A (ko) * 2020-03-13 2021-09-27 엘지전자 주식회사 팬모듈 및 이를 구비하는 휴대형 공기정화기

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5536946U (ja) * 1978-09-01 1980-03-10
JPS5948523B2 (ja) * 1978-09-05 1984-11-27 隆 浦山 交流電磁石
JP3510328B2 (ja) * 1994-06-17 2004-03-29 三菱重工業株式会社 遠心ファン
JP3700217B2 (ja) * 1995-10-31 2005-09-28 株式会社デンソー 遠心式送風機
JP4505885B2 (ja) 1999-06-23 2010-07-21 ダイキン工業株式会社 送風機及びこれを用いた空気調和機並びに空気清浄機
JP4946396B2 (ja) * 2006-11-30 2012-06-06 パナソニック株式会社 遠心送風機

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO2011099286A1 *

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP3006840A1 (en) * 2014-10-10 2016-04-13 Fujitsu General Limited Ceiling-embedded air conditioner
AU2015238895B2 (en) * 2014-10-10 2020-10-08 Fujitsu General Limited Ceiling-embedded air conditioner
US11566634B2 (en) 2018-10-31 2023-01-31 Carrier Corporation Arrangement of centrifugal impeller of a fan for reducing noise

Also Published As

Publication number Publication date
US20120308370A1 (en) 2012-12-06
WO2011099286A1 (ja) 2011-08-18
AU2011215464A1 (en) 2012-09-06
JP4844678B2 (ja) 2011-12-28
KR20120123440A (ko) 2012-11-08
BR112012020088A2 (pt) 2016-05-17
JP2011163235A (ja) 2011-08-25
CN102753836A (zh) 2012-10-24

Similar Documents

Publication Publication Date Title
EP2535594A1 (en) Centrifugal blower
KR101871269B1 (ko) 공기조화기
KR101750877B1 (ko) 송풍팬 및 이를 포함하는 공기조화기
EP1783374A1 (en) Centrifugal blower and air conditionaer with centrifugal blower
JP5783214B2 (ja) 遠心送風機及びこれを備えた空気調和機
JP2006307651A (ja) 多翼ファン
JP2014173580A (ja) 送風装置
US7223068B2 (en) Housing for axial flow heat-dissipating fan
JP2010124534A (ja) 電動機用斜流ファンと該斜流ファンを備えた電動機
JP5195983B2 (ja) 遠心送風機
JP2009041517A (ja) 遠心送風機および車両用空気調和装置
JP5136604B2 (ja) スクロール付遠心送風機
JP2010181058A (ja) 空気調和機
JP2013036444A (ja) 遠心送風機
JP5076324B2 (ja) 遠心ファン
JP5772370B2 (ja) 多翼送風機
JP2012036827A (ja) シロッコファン
JP4872997B2 (ja) 送風機及び該送風機を備えた空気調和機
JP2012211577A (ja) 遠心送風機及びこれを備えた空気調和機
JP2012211576A (ja) 遠心送風機及びこれを備えた空気調和機
EP2090839A1 (en) Air conditioner
KR100833379B1 (ko) 원심 송풍기
JP7416290B2 (ja) 送風機
JP6181908B2 (ja) ブロワ
KR102552595B1 (ko) 임펠러 및 이를 포함하는 환풍기

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: 20120823

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

DAX Request for extension of the european patent (deleted)
STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION HAS BEEN WITHDRAWN

18W Application withdrawn

Effective date: 20140203