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
  • F04D29/02—Selection of particular materials
  • F04D29/023—Selection of particular materials 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
  • F04D29/26—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
  • F04D29/284—Rotors specially for elastic fluids for centrifugal or helico-centrifugal pumps for radial-flow or helico-centrifugal pumps for compressors
• • 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
• • 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
  • F05D2300/00—Materials; Properties thereof
  • F05D2300/40—Organic materials
  • F05D2300/43—Synthetic polymers, e.g. plastics; Rubber

Definitions

• the present invention relates to a radial impeller, in particular for use in Gasge ⁇ blower with steep fan characteristic.
• EP 0 410 271 B1 describes a radial fan for conveying a gaseous medium in a device with high flow resistance, which is in particular a burner in a gas boiler. Such burners have a relatively high flow resistance, which is on the order of 200 Pascal and more.
• the medium to be delivered may be air or a combustible gas-air mixture.
• the blower or its fan wheel must therefore be designed for a steep pressure-volume flow characteristic. This means that pressure changes should be accompanied by only small changes in the volume flow.
• the known fan has for this purpose an impeller whose diameter is more than ten times its flow outlet width.
• first cover plate lower part
• second cover plate circular, flat-plate-shaped lid
• the documents DE 41 41 359 A1, CH 301 116 and DE 102 04 037 A1 also describe similar, likewise closed impellers, wherein according to the first two documents shortened intermediate blades are provided. Such closed, double capped radial impellers are relatively difficult and expensive to manufacture.
• a further radial blower is known from WO 02/45862 A2, which however has a blower wheel with a diameter which is so large in axial length and flow outlet width that this blower is not or less suitable for the preferred application as a gas burner blower is.
• This known impeller has consistently the same length blades and is formed axially open on the hub side.
• the object of the present invention is to provide a radial fan wheel which can be produced in a simple and economical manner with particular suitability for a gas burner fan with a steep characteristic curve.
• the diameter By designing the diameter as at least ten times the flow outlet width of the blades, the desired steep characteristic curve is achieved.
• the blades have free side edges on their side facing away from the cover disk, which edges lie in an imaginary flat or arbitrarily curved surface.
• the radial impeller according to the invention is vorgese ⁇ hen for use in a blower housing, which has a so adapted to the free blade side edges or to the ge of these defined, ge trained surface form wall, that between this wall and the impeller blades only a narrow axial gap is formed.
• the shortened intermediate blades provided according to the invention in each case between two blades have the advantage that, on the one hand, a relatively large number of blades or intermediate blades can be provided, which with respect to the flow guidance in the flow channels formed between the blades with regard to air guidance, flow separation and vortex formation is advantageous.
• the problem is avoided that with a correspondingly large number of long blades passing through to the inlet region, the intake or inflow region would be partially blocked, which would have a negative effect on the delivery volume.
• the radially inner inflow region is kept open in the area of the shorter intermediate vanes.
• an annular cover plate is provided, which has a width RD, which is smaller than the distance edge suction opening to outlet opening-peripheral edge, measured from the edge of the suction opening.
• width is such that it is measured from the intake substantially half a blade length.
• This particular embodiment also allows a production of the impeller as a one-piece molded part, being considered as be ⁇ particularly favorable an embodiment in which the support disk is annular and has a ring width which is substantially the measure outer edge of the cover plate to outlet opening peripheral edge (2-). 3 1 ).
• this ring width is substantially half a blade length, guidance may still be given to the airflow in the exit region, so that the shear friction between the rearward housing wall and the flow is restricted to a reduced range.
• the two disc rings namely that of the cover disc and that of the support disc, either overlap in the projection in the direction of the axis of rotation as required, form a gap between them or complement each other then to a circular area.
• An advantageous flow course can be achieved in that the hub body has a height that corresponds to measured from the plane of the rear support plate substantially half the wheel depth.
• a cone is formed on the hub body toward the flow side, wherein the cover disc (2-9) and the cone of the hub in cross-section A-A have a substantially parallel course. As a result, a favorable flow profile is achieved in the input region of the wheel.
• the flow surface is substantially parallel to the plane of rotation.
• the Strömungs ⁇ surface of the outer peripheral portion is arranged in a plane which is more inwardly with respect to the flow channel than the flow channel limiting surface of the outer support disc, d. That is, the support disk can be made thinner than the thickness of the outer peripheral portion of the cone.
• An advantageous embodiment can be designed so that the blades are axially wider in the intake area than in the outflow area. It may also be favorable that in each case at least one intermediate blade is arranged between the blades substantially in the region of the width of the carrier disk.
• each case two intermediate blades are arranged in pairs.
• the intermediate blades have a radial extension which essentially corresponds to the distance between the outer circumference of the cover disk and the outer circumference of the rear support disk.
• the intermediate blades are held exclusively on the rear support plate.
• This embodiment particularly facilitates the embodiment of the radial fan wheel as a one-piece cast part.
• blower housing suitable for generating a high pressure and for generating a steep characteristic curve, in which a change in the backpressure in the system causes no or only a slight change in the volume flow.
• Fig. 1 is a perspective view of a first embodiment of an inventive
• FIG. 2 is a perspective view of the impeller of FIG. 1 on the other, open _ side of the blades,
• FIG. 6 shows a representation analogous to FIG. 5 in an advantageous development
• Fig. 7 is a plan view of another embodiment with reduced deck
• FIG. 8 shows a view of a section along the line A - A in FIG. 7
• a radial impeller 1 consists of a multiplicity of radial blades 2 which are distributed over the circumference and which extend in the radial direction from an inner inlet region 4 to an outer outlet region 6. 1 and 3, the blades 2 have radially inner end edges 8 which are disposed on an imaginary, approximately cylindrical, but conical, inlet region 4 and in the axial inflow direction (compare the arrow E in FIG and FIGS. 4 to 6) as seen in the inlet region 4 in the tapered surface.
• the blades 2 also have outer end edges 10.
• radial flow channels 12 are formed with a substantially radial Aus ⁇ flow direction A.
• the blades 2 extend axially, i. seen in the direction of a rotation axis 14, zwi ⁇ tween an inlet side 16 and an axially opposite hub side 18 (see the Sch ⁇ ittansichten in Fig. 4 to 6).
• the blades 2 are connected only on their inlet side 16 over their radial extent to the outlet region 6 with a cover disk 20 which has a centric inflow opening 22 opening into the inlet region 4.
• the blades are only connected with their radially inner end areas to a central hub 24, so that the flow channels 12 are designed to be open on this side in the axial direction.
• the blades 2 thus have free side edges 26 on this side.
• the blades 2 and the cover disk 20 define an outer fan wheel diameter D which amounts to at least ten times the axially measured flow outlet width B of the blades present in the exit region 6.
• the axially measured inner flow inlet width C of the blades 2 in the inlet region 4 is greater than the outer flow outlet width in the outlet region 6 (cf., for example, FIG.
• radially shorter intermediate blades 28 are connected to the cover disk 20 in regions respectively disposed between adjacent blades 2 (see in particular FIGS. 1 and 2). These intermediate blades 28 extend from the outer circumference of the cover disk 20 only over part of the Radial extent of the cover plate 20 and terminate at a radial distance from the hub 24. This can best be seen in Fig. 2 detect. In the illustrated embodiment, only one intermediate blade 28 is provided between each two adjacent blades 2, but it is also possible to provide two or more intermediate blades 28, which can then be designed with the same or different radial length.
• the radial impeller 1 can advantageously be produced as a one-piece molded part made of plastic, and preferably as a plastic with such antistatic properties that static charges are avoided during operation or are discharged via an unillustrated housing. This contributes to a high degree of application safety, especially with regard to the preferred application for conveying combustible gas-air mixtures, by avoiding ignition by sparking.
• the blades 2 and the intermediate blades 28 in the radial direction with respect to the direction of rotation 30 gur ⁇ downward curved are formed.
• the blades are arranged such that their entry angle is approximately between 30 ° and 45 ° and their exit angle is approximately between 45 ° and 90 °.
• EP 0410 271 Alternatively, however, an embodiment with forward curved or at the exit region 6 radially ending blades 2 and intermediate blades 28 is possible.
• the hub 24 consists of an outer disk section 32 and a central bearing section 34 to be connected to a shaft, not shown, in particular in the form of a short pipe extension.
• the disc portion 32 is connected at its radially outer periphery with the inner, the inlet portion 4 facing end portions of the blades.
• the disk section 32 of the hub 24 projecting from its outer peripheral region connected to the blades 2 projects into the inlet region 4 and in the direction of the inlet opening 22 of the cover disk 20
• blower functional elements such as bearing elements, motor or rotor parts and / or the like forms.
• the intermediate blades 28 are connected to the cover plate 20 via a respective transition reinforcement 38 formed in the blade root area. This ensures a sufficient stability of the intermediate blades 28 despite the connection-free configuration spaced from the hub 24.
• the blades 2 and the intermediate blades 28 are axially opposite in their radially outer and the cover disk 20. overlying area for mechanical reinforcement via a circumferential, one-piece ange ⁇ molded ring element 40 is connected.
• the cover disk 20 has in the region of the inflow opening 22 an edge 42 which is nozzle-like in the flow direction.
• FIGS. 7 and 8 show a further embodiment for achieving the object according to the invention.
• the reference numerals are provided with a number 2 and hyphen in the embodiment described now.
• the radial fan wheel 2-1 shown in FIG. 7 has an annular cover disk 2-9 which annularly surrounds the suction region 2-7.
• a circular suction opening 2-10 is formed on the cover plate 2-9, which is surrounded by a circumferential opening lip 2-10 '.
• the radial impeller 2-1 further includes a hub body 2-2 and a peripheral edge 2-3.
• the hub body 2-2 has a cone 2-2 'on its side facing the intake opening 2-10.
• the impeller 2-1 is equipped with the hub body 2-2 to the peripheral edge 2-3 substantially radially extending blades 2-6.
• the vanes define an intake region 2-7 and an outflow region 2-8.
• the annular cover plate 2-9 has a width R D , which measured from the edge of the suction port (2- 10) is half the distance edge-outlet opening circumference 2-3.
• the width R 0 thus corresponds to substantially half of the blade length measured along the upper edge of the blade 2-6.
• the foot of such a blade is integrally connected at its radially inner tip with the hub body.
• the extending on the rear side 2-5 support disc 2-11 is ring ⁇ shaped and has on its ring a width ⁇ R at which voltage from the edge of Ansaugöff ⁇ measured 2-10, substantially half the rated edge outlet opening 2-10 - peripheral edge is 2-3. This corresponds essentially to half the length of the blade, measured along the back edge of the blade jet between the peripheral edge 2-3 and the base of the blade 2-6 on the cone 2-2 'of the hub 2-2.
• the hub body 2-2 has a height which, measured from the plane of the rear support plate 2-11 substantially equal to half the wheel height.
• the height of the hub is half the height of the blades projecting into the suction port 2-10.
• the surface F ⁇ of the cone 2-2 'of the hub 2-2 extends substantially parallel to the inner surface F D cover plate 2-9.
• a region 2-21 is formed, the surface of which runs essentially parallel to the plane of rotation of the blower wheel.
• the flow-facing surface of the cone and the rotation-parallel region are rounded.
• intermediate blades 2-16 are arranged substantially in the region of the width of the rear support disk 2-11. The number of blades 2-16 may vary depending on the application.
• two intermediate blades 2-16 are arranged in pairs between two blades 2-6.
• the radial extension of the intermediate blades 2-16 is dimensioned such that it corresponds substantially to the distance 2-17 between the outer circumference 2-18 of the cover disk 2-9 and the outer circumference 2-19 of the rear support disk 2-11.
• the insects ⁇ blades are 2-16 held exclusively on the rear support plate 2-11, ie, the front edge of the intermediate blades are free in this embodiment.
• the intermediate blades can also be formed on the cover plate.
• the shape of the intermediate blades corresponds in its course essentially the corresponding design of the portion of the blades 2-6 at entspre ⁇ chender place.
• the preceding embodiment can also advantageously be produced as a one-piece molded part made of plastic

Landscapes

• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Structures Of Non-Positive Displacement Pumps (AREA)

Priority Applications (1)

Applications Claiming Priority (2)

Related Child Applications (2)

Publications (2)

Family

ID=35453467

Family Applications (2)

Family Applications After (1)

Country Status (5)

Families Citing this family (42)

Family Cites Families (27)

• 2004
  • 2004-07-31 DE DE202004012015U patent/DE202004012015U1/de not_active Expired - Lifetime
• 2005
  • 2005-07-29 EP EP05768016A patent/EP1774180B1/fr active Active
  • 2005-07-29 WO PCT/EP2005/008250 patent/WO2006013067A2/fr active Application Filing
  • 2005-07-29 US US11/658,906 patent/US7794206B2/en active Active
  • 2005-07-29 AT AT05768016T patent/ATE544953T1/de active
  • 2005-07-29 EP EP10157619.7A patent/EP2196679B1/fr active Active
• 2009
  • 2009-12-23 US US12/646,032 patent/US8109731B2/en active Active

Non-Patent Citations (1)

Also Published As

Similar Documents

Legal Events