EP3872351A1 - Ventilatorrad eines axial- oder diagonalventilators mit wuchtring - Google Patents

Ventilatorrad eines axial- oder diagonalventilators mit wuchtring Download PDF

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Publication number
EP3872351A1
EP3872351A1 EP20213414.4A EP20213414A EP3872351A1 EP 3872351 A1 EP3872351 A1 EP 3872351A1 EP 20213414 A EP20213414 A EP 20213414A EP 3872351 A1 EP3872351 A1 EP 3872351A1
Authority
EP
European Patent Office
Prior art keywords
ring
balancing
fan wheel
centrifugal
axial
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.)
Pending
Application number
EP20213414.4A
Other languages
German (de)
English (en)
French (fr)
Inventor
Thorsten Pissarczyk
Daniel Gebert
Martin Baer
Johannes Dörr
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.)
Ebm Papst Mulfingen GmbH and Co KG
Original Assignee
Ebm Papst Mulfingen GmbH and Co KG
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 Ebm Papst Mulfingen GmbH and Co KG filed Critical Ebm Papst Mulfingen GmbH and Co KG
Publication of EP3872351A1 publication Critical patent/EP3872351A1/de
Pending legal-status Critical Current

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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
    • F04D29/325—Rotors specially for elastic fluids for axial flow pumps for axial flow fans
    • F04D29/326—Rotors specially for elastic fluids for axial flow pumps for axial flow fans comprising a rotating shroud
    • 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
    • F04D29/05—Shafts or bearings, or assemblies thereof, specially adapted for elastic fluid pumps
    • F04D29/051—Axial thrust balancing
    • F04D29/0516—Axial thrust balancing balancing pistons
    • 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
    • F04D29/388—Blades characterised by construction
    • 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
    • F04D29/662—Balancing of rotors
    • 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
    • F05D2230/00—Manufacture
    • F05D2230/50—Building or constructing in particular ways
    • F05D2230/53—Building or constructing in particular ways by integrally manufacturing a component, e.g. by milling from a billet or one piece construction

Definitions

  • the invention relates to a fan wheel of an axial or diagonal fan with improved balancing properties.
  • the fan wheel of an axial or diagonal fan must be balanced to reduce noise and to increase the service life of the installed bearings. This is usually done by inserting balancing weights in appropriate pockets or by attaching balancing elements.
  • the fully formed fan wheels are, for example, by means of Balancing clips or balancing clips balanced. These balancing elements can be placed in balancing pockets provided on the fan wheel.
  • the DE 10 2006 057087 B3 discloses an impeller for a fan which comprises a hub for connecting the impeller to the rotor of a drive motor and fan blades which are arranged on the hub. Furthermore, pockets for inserting balancing weights are provided outside the flow path of the impeller, these pockets being arranged in particular on the hub of the impeller.
  • an impeller for a fan having a hub for connecting the impeller to a drive motor and fan blades extending radially outward from the hub.
  • pockets for inserting balancing weights are at least partially arranged in the fan blades.
  • the arrangement of the pockets in the fan blades means that the external geometry of the fan wheel is retained.
  • the pockets for the balancing weights are sunk into the fan blades so that they open into the support ring on which the fan blades are attached.
  • an arrangement of the balancing elements in the fan blades is very complex to implement.
  • a disadvantage of these solutions is that the balancing elements are arranged in the area through which air flows, for example directly on the slinger in the nozzle gap of the blower or in its immediate vicinity. As a result, disturbing flow noises can be generated both by the balancing elements themselves and by empty balancing pockets. Furthermore, deformation of the slinger is promoted by centrifugal forces.
  • the disadvantage of balancing pockets in radial gears is that the balancing elements are not can only be plugged in from one side.
  • the object of the present invention is to provide a fan wheel of an axial or diagonal fan with a rotating centrifugal ring, in which the imbalance is balanced with balancing weights without negatively affecting the acoustics and strength and the balancing weights can be mounted from one side.
  • a fan wheel of an axial or diagonal fan with a hub and a plurality of impeller blades arranged around an axis of rotation of the fan wheel which extend radially outward from the hub and whose radially outer end is surrounded by a rotating centrifugal ring.
  • On the slinger at least one balancing ring is provided which encircles the slinger and is designed with a free axial edge for the fastening arrangement of at least one balancing weight.
  • the advantage of the balancing ring surrounding the centrifugal ring is that the balancing weights are not arranged in a nozzle gap between an inlet nozzle of the axial or diagonal fan and the centrifugal ring. Neither the balancing ring nor the balancing weights affect the flow path of the air flow generated by the fan wheel, so that a negative influence on the acoustics or the air flow is avoided. Furthermore, the strength of the slinger is improved by the at least one balancing ring, as a result of which the loading capacity due to mechanical loads is increased before component failure occurs. Since the slinger is not significantly different in operation due to the increased strength deformed, a negative impact on the acoustics and the efficiency of the axial or diagonal fan is kept as low as possible.
  • the at least one balancing ring completely surrounds the slinger. It is advantageous that a completely circumferential balancing ring, the rigidity of the fan wheel is further improved.
  • the balancing weights can be arranged on the balancing ring in any angular position of the latter.
  • the at least one balancing ring is formed in one piece on the centrifugal ring.
  • the fan wheel is preferably designed in such a way that the at least one balancing ring protrudes from a radial outer circumferential surface of the centrifugal ring and is connected axially on one side to the outer circumferential surface.
  • the free axial edge is designed for the fastening arrangement of the at least one balancing weight.
  • the at least one balancing ring is arranged axially spaced apart from a suction-side axial edge of the centrifugal ring by an axial distance.
  • the axial distance A between the suction-side axial edge of the slinger and the free axial edge of the at least one balancing ring is designed in a ratio to a wall thickness Ts of the slinger, that is 1 A / Ts 20, preferably 2 ⁇ A / Ts ⁇ 10.
  • the area defined in this way for the axial distance is dimensioned sufficiently large with regard to influencing the acoustics or the air flow that negative effects are reduced.
  • the strength is increased by an arrangement spaced apart from the free axial edge.
  • the at least one balancing ring extends, starting from an axial edge of the centrifugal ring on the exhaust side, in the direction of an intake side of the fan wheel. It is advantageous that the free axial edge of the balancing ring for the fastening arrangement of the at least one balancing weight always points in the axial direction towards the suction side, so that a balancing weight can always be mounted from this easily accessible side. Furthermore, due to the one mounting direction and the orientation of the fan wheel, the balancing weights cannot detach from the balancing ring due to centrifugal forces.
  • an embodiment is favorable in which the outlet-side axial edge of the centrifugal ring is designed to be turned over in the axial direction and thereby produces a turned-over section which forms the at least one balancing ring.
  • the arrangement of the balancing ring on the axial edge of the centrifugal ring on the exhaust side is favorable, since the air flow is at this position is not influenced by the balancing ring due to the fan wheel, which has a positive effect on the acoustics.
  • the axial edge of the centrifugal ring on the outlet side forms an extreme point of the fan wheel. Balancing the forces resulting from the imbalance at this position is therefore particularly favorable.
  • the at least one balancing ring is arranged in an axial plane so as to overlap the impeller blades.
  • the at least one balancing ring is arranged on the slinger in an axial plane of an axial end section of the impeller blades.
  • the fan wheel according to the invention is designed in an embodiment variant that radial stiffening ribs are arranged between an outer circumferential surface of the centrifugal ring and an inner circumferential surface of the at least one balancing ring.
  • the advantage of this is that the strength of the balancing ring and the slinger is improved. This improves component protection and helps prevent the slinger from deforming significantly during operation, which counteracts any negative impact on the acoustics and the efficiency of the fan.
  • the stiffening ribs preferably have one to the axis of rotation parallel longitudinal extension and extend from the outer circumferential surface of the slinger in a straight line radially outward to the inner circumferential surface of the balancing ring. In this way, receptacles for the balancing weights are formed between the stiffening ribs.
  • a receiving area is defined between the slinger and the balancing ring, which area increases in the axial direction by increasing a radial distance between the slinger and the balancing ring.
  • this increases the installation space made available for mounting the balancing weights on the free axial edge of the slinger.
  • this prevents the fan wheel from being destroyed in the event of ice formation which occurs in certain applications, since the ice can expand.
  • a variant is favorable in which the entire fan wheel is formed in one piece.
  • the advantage of this is that the fan wheel can be manufactured in one manufacturing process, for example injection molding, and further complex assembly steps of the balancing ring on the slinger are dispensed with.
  • a one-piece fan wheel has high strength.
  • a wall thickness Tw of the balancing ring and a wall thickness Ts of the centrifugal ring are designed in a ratio that 0.3 Tw / Ts 3.0, in particular 0.5 Tw / Ts 2.0.
  • An embodiment variant is advantageous in which two balancing rings axially spaced from one another are provided on the slinger. Through the two Balancing rings, the strength of the slinger is greatly improved and thus has the advantages already described above. In addition, two positions for balancing are provided along the axis of rotation.
  • an axial fan or diagonal fan with a fan wheel with one of the above features is provided.
  • FIG 1 is a perspective view of a fan wheel 1 of a diagonal fan with two balancing rings 5, 5 '.
  • the fan wheel 1 has a hub 2 and a plurality of impeller blades 3 which extend radially outward from the hub 2 and the radially outer end of which is enclosed by a rotating centrifugal ring 4.
  • the balancing weights 14 are, for example, balancing clips which are attached to the corresponding free axial edge 6, 6 'of the balancing rings 5, 5' by being pushed onto the free axial edge 6.
  • the two balancing rings 5, 5 ' enclose the slinger 4 completely circumferentially and are arranged axially spaced from one another on the outer jacket surface 7 of the slinger 4. Furthermore, one of the balancing rings 5 'extends from an exhaust-side axial edge 9 of the centrifugal ring 4 in the direction of a suction side 10 of the fan wheel 1.
  • the other balancing ring 5 is axially spaced from an suction-side axial edge 8 of the centrifugal ring 4 and also extends in the direction of the suction side 10.
  • the balancing rings 5, 5 ' are arranged on the slinger 4 in such a way that a receiving area 12 is defined between the slinger 4 and the balancing rings 5, 5', which is created by increasing a radial distance between the slinger 4 and the balancing rings 5, 5 'enlarged in the axial direction.
  • radial stiffening ribs 11 are provided between an outer circumferential surface 7 of the throwing ring 4 and an inner circumferential surface of the balancing rings 5, 5 ', which are evenly spaced over the entire circumference of the throwing ring 4 on the outer circumferential surface 7.
  • the stiffening ribs 11 have a longitudinal extension parallel to the axis of rotation RA and run in a straight line from the outer circumferential surface 7 of the slinger 4 radially outward to the inner circumferential surface of the respective balancing ring 5, 5 '.
  • the receiving area 12 is divided by means of the stiffening ribs 11 into a large number of corresponding individual areas, each of which is dimensioned to receive a balancing weight 14.
  • the fan wheel is stiffened accordingly 1 through the stiffening ribs 11 in the area in which the balancing weights 14 are arranged.
  • Alternative designs include stiffening ribs 11 running at an angle to the radial extension.
  • Figure 2 shows a sectional view of the in Figure 1 described fan wheel 1 of a diagonal fan.
  • the diameter of the fan wheel 1 increases convexly from an intake side 10 in the direction of the axial edge 9 on the exhaust side.
  • the outer circumferential surface of the hub 2 runs concavely from the intake side 10 in the direction of the exhaust side.
  • the two balancing rings 5, 5 ' are integrally formed on the slinger 4.
  • the balancing rings 5, 5 ′ protrude from the radial outer circumferential surface 7 of the slinger 4 and are axially connected to the outer circumferential surface 7 on one side.
  • the entire fan wheel 1 is formed in one piece.
  • the outlet-side axial edge 9 of the thrower ring 4 is designed to be turned over in the axial direction and produces a turned-over section which forms a balancing ring 5 '.
  • the other balancing ring 5 is arranged axially spaced apart from an intake-side axial edge 8 of the slinger 4 by an axial distance A and also extends in the direction of an intake side 10 of the fan wheel 1 the corresponding extension in the direction of the suction side 10 is determined between the slinger 4 and the balancing rings 5, 5 'of the receiving area 12.
  • the wall thickness Ts is constant.
  • the impeller blades 3 extend curved on the centrifugal ring 4 to the axial edge 9 on the exhaust side, and the impeller blades 3 extend curved over the entire outer circumferential surface on the hub 2. Furthermore, in Figure 2 shown that the one balancing ring 5 is arranged on the slinger 4 in an axial plane of an axial end section 13 of the impeller blades 3.
  • the wall thickness Tw is constant.
  • FIG 3 is a sectional view of a diagonal fan 100 with a fan wheel 1 with two balancing rings 5, 5 'shown, which corresponds to that in the Figures 1 and 2 described fan wheel 1 is formed.
  • Both of the balancing rings 5 are arranged in an axial plane so as to overlap with respect to the impeller blades 3.
  • the housing of the diagonal fan 100 forms a concave running inlet nozzle on the suction side, through which an air flow of the diagonal fan is sucked in and which extends to the centrifugal ring 4 in an overlapping manner in an axial plane. In this way, a nozzle gap DS is formed between the inlet nozzle and the slinger 4.
  • the diagonal fan 100 also has a guide device for a uniform outlet flow with a multiplicity of impeller blades distributed in the circumferential direction, which connects from the suction side 10 to the fan wheel 1 or the hub 2.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Structures Of Non-Positive Displacement Pumps (AREA)
EP20213414.4A 2020-02-26 2020-12-11 Ventilatorrad eines axial- oder diagonalventilators mit wuchtring Pending EP3872351A1 (de)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DE102020104985.4A DE102020104985A1 (de) 2020-02-26 2020-02-26 Ventilatorrad eines Axial- oder Diagonalventilators mit Wuchtring

Publications (1)

Publication Number Publication Date
EP3872351A1 true EP3872351A1 (de) 2021-09-01

Family

ID=73834271

Family Applications (1)

Application Number Title Priority Date Filing Date
EP20213414.4A Pending EP3872351A1 (de) 2020-02-26 2020-12-11 Ventilatorrad eines axial- oder diagonalventilators mit wuchtring

Country Status (3)

Country Link
EP (1) EP3872351A1 (zh)
CN (1) CN113309718B (zh)
DE (1) DE102020104985A1 (zh)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102022131248A1 (de) 2022-11-25 2024-05-29 Ebm-Papst Mulfingen Gmbh & Co. Kg Diagonallaufrad mit variierender Nabenfläche

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102006057087B3 (de) 2006-12-04 2008-06-19 Minebea Co., Ltd. Laufrad für ein Gebläse
DE202007005784U1 (de) * 2007-04-21 2008-08-21 Ebm-Papst Mulfingen Gmbh & Co. Kg Lüftungseinheit zur Fremdbelüftung eines Elektromotors
DE102008041858A1 (de) * 2008-09-08 2010-03-11 Robert Bosch Gmbh Motorkühlungsgebläse mit dynamischem Unwuchtausgleich
DE102011000208A1 (de) 2011-01-19 2012-07-19 Minebea Co., Ltd. Laufrad für ein Gebläse
DE202018106513U1 (de) * 2018-11-16 2018-11-22 Ebm-Papst Mulfingen Gmbh & Co. Kg Diagonalventilator mit optimiertem Diagonallaufrad

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FI20011135A0 (fi) 2001-05-31 2001-05-31 Flaekt Oy Puhaltimen siipipyörän tasapainotus
US20120121410A1 (en) 2010-11-11 2012-05-17 Wen-Hao Liu Round axial fan with balancing structure
DE102013212341A1 (de) 2013-06-26 2014-12-31 Behr Gmbh & Co. Kg Lüftervorrichtung und Verfahren zur Auswuchtung
ITUB20152894A1 (it) * 2015-08-05 2017-02-05 Spal Automotive Srl Ventilatore assiale
DE102018128823A1 (de) * 2018-11-16 2020-05-20 Ebm-Papst Mulfingen Gmbh & Co. Kg Diagonalventilator mit Heizelement
DE102018128820A1 (de) * 2018-11-16 2020-05-20 Ebm-Papst Mulfingen Gmbh & Co. Kg Diagonalventilator mit optimiertem Gehäuse

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102006057087B3 (de) 2006-12-04 2008-06-19 Minebea Co., Ltd. Laufrad für ein Gebläse
DE202007005784U1 (de) * 2007-04-21 2008-08-21 Ebm-Papst Mulfingen Gmbh & Co. Kg Lüftungseinheit zur Fremdbelüftung eines Elektromotors
DE102008041858A1 (de) * 2008-09-08 2010-03-11 Robert Bosch Gmbh Motorkühlungsgebläse mit dynamischem Unwuchtausgleich
DE102011000208A1 (de) 2011-01-19 2012-07-19 Minebea Co., Ltd. Laufrad für ein Gebläse
DE202018106513U1 (de) * 2018-11-16 2018-11-22 Ebm-Papst Mulfingen Gmbh & Co. Kg Diagonalventilator mit optimiertem Diagonallaufrad

Also Published As

Publication number Publication date
CN113309718B (zh) 2023-09-29
DE102020104985A1 (de) 2021-08-26
CN113309718A (zh) 2021-08-27

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