GB2192432A - Sheet-metal impeller for coolant pumps - Google Patents

Description

1 GB 2 192 432 A 1 SPECIFICATION It is the aim of the invention to create

a small.

impellerwith relatively high discharge capacityin Sheet-metaf impelferof littfedischargecapacity, [eight-weight design for motor veh iclecool ant pumps especiallyfor coofan.tpurrfps andforpumps in household utensils. Ithas the - 70 advantage of short fabrication time,-increased effi The invention concerns a sheet-metal impeller of ciency and offersthe possibilityto select different little discharge capacity, which is applied in coolant mounting dimensions and even attachments of the pumps of motorvehicles or in pumps of household, ring gaskets for shafts and face seals dueto inner utensils. diameter variability. Itguarantees a good rinsing and Asheet-metal impellertype deep-drawing for motor 75 cooling of the face seal on the impeller back.

vehicle coolant pumps is known which has in its The task of the invention isto create a sheet-metal centre at the inlet area two-staged cylindrical seats. impeller of little capaGityforcoolant pumps which The one with the greater diameter holds on the back of elevates the discharge capacity with increase of the impel lerthe packing ring of a face seal via a rubber discharge pressure and reduction of the split losses in angle ring. The cylindrical seat with the smaller 80 the main discharge flow. At a cast impeller this-can be diameter is calibrated from the outside. The hub forms reached in the acceleration zone by new technological the stop forthe seaton the shaft. Atthe circumference means which cannot be realized during the casting of the impeller rectangularto the impellerwheel there and machining process bya forming and machining are several paddles, which pointwith their blade technology as well as at existing shaftsealing position into the direction of the cyindrical seat 85 elements at the back of the impeller nearthe shaft.by bended off in an angle to symmetrically divided means for liquid and heat dissipation atthe ring tange -ts to the plate circumference and to the delivery gasket couple for intensive rinsing into the casing o direction. The blades are reinforced atthe bladeroots -the face seal.

by a notch crease of 45'tothe impellerwheel.The At a compactsheet-metal impellerof little discharge dissipation of heatfrom the ceramics packing ring to 90 capacity for coolant pumps with circulation slits the impeller is bad because of the coating Of the between every second paddle having an annularly packing ring of a face seal over a ring of rubber into the stiffening stabilization curl round the central hub of a back of the impeller. The back of the impeller is rarely deep-drawn plate in orderto expand the shrink.area is flown behind by coolant because of the closed according to the invention the end of the hub formed formation of the impeller wheel.-This leads to in- 95-'to a face collar for the shaft clamping packing ring of a creased temperatures and a reduced service time of face seal. The referred plate is one-sidedly setwith the face seal. This formation of the impeller wheel some rectangularly bended off paddles standing in an does notallowthe attaching of heat dissipation angleto thetangent atthe plate circumference and supporting elements.The outward bulging of the having.onewebto the plate each. Furthermorethe cylindrical seat for the packing ring at the suction port 100 free paddle edges are equipped with a locking flank into the inlet region of the impeller is flow-technologi- each which radially broaden towards the paddle end callyunfavourable. This results in increasing losses of forming an acceleration zone by narrowing the free energy due to impact and flow resistance, cavitation channel cross section. Besides thisthe sheet-metal and a bad efficiency because-of the lack of a i mpeller has between the face area and the back of the continuous transition from axial to discharge flow into 105 plate an annular circulation space beginning at-the the radial region.The innerregion of the casing of the hub. Intothis circulation space rech several blades face seal is located in a damping zone, which causes which are formed bythe face collar by axiallyangled accumulation of deposits. cuts adjacentto openings pointingto the backofthe Inthe acceleration zone atthe slitoccur between the plate.

paddles and the-casing considerable flow losses at the 110 Furthermore the radial face collar can e i t., an pressure side compar - ed with the su ctionside,which into the hub insertable collar bushing having in its at increasing speed leadsto a lower effic iency.The bottom a through hole.

arising slit losses are considerable. The blades can also be formed by radially angled - With coolant pumps operating at high speed range cuts in axial direction from the cylindrical hub. In the life of the face seal is decisively dependent on the 115 another version the blades can be formed by a - extend of heat dissipation and the preventing of separate part closely attached to the hub orthe collar deposits hindering the adjustment of the face seal. bushing.

A known so[ utionfor better cool ing-of the face seals The invention isto explain in the following example arranged on the back ofthe impeller are relief slots in design.

impeller wheels (see DE 2523396). It is unusual to 120 fig. 1: The onepiece sheet-metal impellerwith its arrange edge slots in sheet-metal impellers because face collar, the circulation slits and the into the.

of stabilization risks. circulation space reaching blades in frontview in A compact sheet-metaJ impeJJ,,wwiXh;an, a.n,nuliarly section vertical stiffe.ni.n.g, stabi.i.iZaffQritcurliexp,72,indfngtjh,e, fii,gj, 2,Th1,.e sheet-metal impeller according to-fig. 1 slirinkareaissttQwninthe-paWDEZM, 5M 125 with radially,, broadening locking flanks at the paddle Because ofthe manobtackdesif;ln sh(iwm there which endsintopview.

i grates the packing ring into the casing of the face fig. 3: Thesheetmetal impeller assembled with the seal there exists alsoan unsufficient cooling in the face collarformed by the collar bushing in frontview, face seal especiallywiththeface seal ring arrange- cut, and ment on the impeller back, 130 fig. 4: The sheet-metal impeller according to fig. 3 in 2 GI3 2 192 432 A 2 top view. The formation of the radial locking flank 10 at paddle The sheet-metal impeller consists of a plate 2 with side working completely in the main discharge flow in -central hub 3 and the paddles 4. The transition to th-e - acceleration zone, 11 decreases slit losses in the main hub 3 is formed by a stabilization curl 4, which has the discharge flow and increases the performance of the taskto enable a co m pact sheet-meta I impeller 1.and at 70 sheet-metal impeller 1. Atthe acceleration zone 11, an the sametimeto reinforce the zone forthe hub 3 in - area of higher pressure, a partial stream reaches the such a mannerthattheforce-clOsed connection to-the back of the sheet- metal impeller 1 upto the circulation stub shaft is ensured. In figure 1 the stabilization curl -4 space 16 nearthe shaft,where the blades 14 adjacent is bowed towardsthe paddle side-of the sheet-metal totheface collar nearthe shaftgrasp and eddy it impeller 1 and changes into'the.hub 3. Insidethe plate 75 causing thetemperature drop in this space. Thereby 2there are between two paddles7 circulation slits 5 thefalling of temperature of the packing ring adjacent which are open towardsthe edge of the plate 2. The to theface area 12 and tightly connected with the shaft edge of plate 2 is occupied by Several rectangularly via,itswhole circumferential surface and the openings - angular paddles7 atthe plate circumference having a 15 is obtained. Atthe same timetemperature drop and performance dependently selectable angle towards 80 rinsing into the f ice seal casing is reached to avoid the the tangent. These paddles 7 are reinforced in the formation of deposits favoured by quietzones inside paddle roots by a web 6 to the:plate 2 of the the casing of the face seal. Even with the more narrow sheet-metal impeller 1 in theform of a notch crease of circulation space in figure 3 this function is guaran 45'. The free end of the paddles 7 has atthe paddle teed. Via the edge open circulation slit 5 a Steady edge 8 towards the paddle end 9 a locking flank 10 85 transition from the cooling space into the suction which radially broadens. The locking flank 10 mini- room, a space of lower pressure, is ensured. The use mizes the slit losses in'the main discharge stream of the sheet-me.tal impeller 1 with its specific charac arising from the choosen distanceto the pump casing teristics-in vehicle coolant pumps however results in -wall in'the a=elerdfiorf zone 11. Atthe back of the - an increase of the efficiency of the pump by 20%. In sheetmetal impekFrl exists-a -shaft sealing towards 90 comparisontoa cast impeller the discharge capacity thehub3ofthesheet-ffietal impellerl intheform of a raisesatthesame pressure and speed by50%,i.e.that - fa&esealwhich licl-did-tightly-closes the pumpcasing for achieving the same discharge capacity per minute - atthedrivitig side: Besides this the packing ring ofthe a lower speed is required, e.g. instead of n=6000 fke 8eal-axiallya'djaCentfoth-eface area 12 isstrongly min-'.

intorsion aridtightl'younriecte'd with the stub shaft., 95 The lockingflank 10 causes the stabilization ofthe Theaxially readjustable pabUng ring ofthefaceseal is - characterization of the characteristic performance line -hold,"iriside the face seal casihq strongly in torsion. of the pump by the decreased slit losses, i.e. thatthe Because oftlieface collarl-2 being radially formed former existing performance drop of the discharge ina-s_elected'di tan1ce_off the'back of plate 2 an annular pressure with high discharge capacities shows only a circulation space 16 is created beginning at hub 3. Into 100 small fall. The speed reduction possible bythis over thii;circul'atioh space 16 reachadjacentto openings 15 the whole load range of the coolant pump results also blades 14 pointing to the back of plate 2 and which are - in the expected life rise aswell as the temperature foFmad bythe fa-6e dollar 12 by cuts 13 angular in axial drop and improved rinsing cause a high operation direction. safety of the face seal.

Claims (5)

1. Forcases of equipping different shaft diameters 105 CLAIMS with this

   sheet-metal impeller 1 the application of 1. The sheet-metal impeller of little discharge collarbushing 17 holding the,blades 14 presents itself capacity especiallyfor coolant pumps with circulation according to figures 3 and 4. Here the stabilizationcurl slit between every second paddle blades having an 4 is formed at the driving side and then changes into annularly stiffening stabilization curl round the central -the hub 3 with face stop forthestub shaftatthe paddle 110 fiub of a deep- drawn plate in orderto expand the side. Face collar 12 as bea ring fo rthe-packing ring of a shrink area whereasthe plate is at its edges one face seal hereby is radiallyformed onto the collar sidedly setwith some rectangularly bended W paddle bushing 17. The blades 1-4are also formed by cuts 13 blades standing in an angleto the tangent along with adjacent to openings 15 by axial angularity. Because the plate periphery and thepaddle blades having one of the formation of the.stabilizdtion curl 4the 115 webto the plate each is characterized bythefacts that circulation space 16 is more n arrow. the end of the hub (3) isformed toface collar (1 2)for In accordance with a version not presented with the the shaft.clamping packing ring of a face seal, that the drawings the blades 14 adjaceritto openings 15 can be free paddle edges (8) are equipped with a locking flank formed by radially angular axial cuts 13 out of the (10) each which radially broaden towardsthe paddle cylindrical hub 3.

   120 area (9) forming an acceleration zone (11) by narrow According to another Version not presented with the ing with these paddles (7) the free channel cross deawi ngs the blades 14 can be formed byseparatepart section, and that the sheet-metal impeller (1) has closely connected to the hub 3 orthe collar bushing 17. between the face collar (12) beginning atthe hub (3), The sheet-metal impellerl isfastened in a not into which several blades (14) reach formed by the drawn pump casing-radially ending with a coiled 125 face collar (12) by axially angular cuts (13) adjacentto passage, in the centre on a not drawn stub shaft openings (1 5) pointing to the back of the plate (2).

   ending flushly in the hub 3 of'sheet-metal impeller 1.
2. 2. Sheet-metal impeller according to claim 1 The liquid is axiailyfed atthe suction. port in the inlet characterized bythe fact thatthe radial face collar (12) area via the shaft. The liquid comes into the accellera- is formed by a collar bushing (17) insertable into the tion zone 11 and is radially speeded up. 130hub(3).
3. 3 GB 2 192 432 A 3 3. Sheet-metal impeller according to claim 1 or 2 characterized bythefactthatthe blades (14) are formed bythoeyfindrfealh,u;b(,3.
4. 4. Sheet-metalimpeller-accordfngto.ci'a[m2 - 5 characterized by the fact thatthe blades (14) are formed by a separate part round the hub (3) orthe collar bushing (17).
5. 5. Sheet-metal impumit;i ab,icajijit-,d in Claim 1 substantially as described with reference to Figures 1 and 2 or Figures 3 and 4 of the accompanying drawings.

   Printed in the United Kingdom for Her majesty's stationery Office by the Tweeddale Press Group, 8991685, 1188 18996. Published at the Patent Office, 25 Southampton Buildings, London WC2A lAY, from which copies may be obtained.