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Publication numberUS2767906 A
Publication typeGrant
Publication dateOct 23, 1956
Filing dateNov 7, 1952
Priority dateNov 7, 1952
Publication numberUS 2767906 A, US 2767906A, US-A-2767906, US2767906 A, US2767906A
InventorsDoyle Dewey I
Original AssigneeDoyle Vacuum Cleaner Co
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Centrifugal fan wheel
US 2767906 A
Images(2)
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Description  (OCR text may contain errors)

ocf. 2s, 1956 Filed Nov. '7, 1952 D. l. DoYLE 2,767,906

CENTRIFUGAL FAN WHEEL 2 shets-sheet 1 l V l l I I I l l l I I l l JNVENTOR: DEWEY I. DOYLE BY Oct. 23, 1956 D. LDOYLE 2,767,906

-CENTRIFUGAL FAN WHEEL lFiled Nov. 7, .1952 2 Sheets-Sheet 2 FIiG. 3

' INVENTOR: DEWEY l. DOYLEv BY United aStates Patent {lice 2,767,9dh Patented Oct. 23, 1956 V2,76'7g'906 CENTRIFJUGAL Dewey I. Doyle, Grand RapidsLMich.,{assigner-itu'Doyle Vacuum 'Cleaner Compny, Grand Rapids, Mich., a 'corporation yof Michigan Application November 7, 1952. serriNo. s195`7s "8 Claims (Cl. 2304134) 'This Yinvention relates in general lto centrifugal fan wheelsy andis more particularly directed to .improvements in -suc'h Vfan wheels which are especially'd'esign'e'd tocreateeither a suction or ablowing elect. I,

The improved centrifugal rfan wheel 'embed uin'g V1the upresent 4invention may have Vmany uses in l'co'mbiriation with various types -of machines lto produce .various results.

However, the .particular design disclosed xher'e'inis especially adapted-for use in vacuum cleaners.

4It has been customary in the past to design 'Vacuum cleaners either for the production `of'liigh volume `-o'r'fr the production of what'is Iknown as fa'high s'taticsiiction. In lcommercial or 'industrial tank type vaciiurn 'cleaners the particular design has in the 'past depended `upon 'the 'enduse of the vacuum cleaner. Where the purchaserf the product expects to'use the vacuum cleaner Awith lthe hose substantially open h`e is more interested in a 'high volume of air 4passing through the y'maehine i However, where the machine is to be used undefrci'rcumstances where the hose end `willvbe Vpartially 'closed `'such as in the cleaning of r-u'gsva'nd upholstered furniture, it is more desirable that la hi'g'h static condition prevail. IUp to -the present ytime -vacu'm cleaner'sfwhich refdsigned to produce a high "volume inherently ihave la 'low static condition; likewise, a machine that is especia y designed to produce la high static will inherently 'result in a reduced volume. v n

In order tomore clearly 'understand 'the 'terms high orkllow static and high or low'ioltiinefv a brief 'description ofthe test involved in determining 'these factors will'bepresented. The actual amount'of static or vluriie is customarny stated in reims of wafer un. 'rn 'refining tests to determine these faetors, a 'U-'shap'ed'tbeiis v:einployedhaving a predetermined number of inches of lwater therein. One end 'of vthe U tube 'remains 'open itty the atmosphere and lthe other end of the Uftube is connected by means of -a hose to an opening in "the side ofthe inlet into the vacuum cleaner tank. With 'the machine 'in 'operation and creating a vacuum at the iiile't to the tank the water lift will -be increased as the size ffthefinlet is decreased. When the inlet is completely closed the number of inches ythat the 'water'is vdrawn upwardly into one side of the ll tube and is forced downwardlyin the other side of the 'U tube is l'referred to as the closed water -li-ft. This -is a measure of the vstatic suction. l

As the inlet opening to the tank is enlarged in area the water in the AU tube will fall and the number of inches of wa'ter lift for 'a given 'size opening may then be'trans'lated into terms of volume.

`Industrial 'tank type vacuum cleaners designed paracularly te produce 'alhign volume :or .1a relatively nigh Wafer lift :W'le'n l:the inlet K the 'tank fis I'clrfplfl-y fqop'n `trsmily'have a single ran when eminoaly a s'rngflestage. Fan 'wheeiswhich haveiaa-depsig dr" the present time when used as asiriglesxtage are' pable of prod'cing 'avery high static suction and e'an therefore sensed:onlyrdrspeciae purp''ses,

.-.In order to increase the static suction ina vacuum "cleaner it'is customary to increase the number of ian wheelstotwo `or three and sometimes more all mounted 'bo`n`the sarnemotor shaft. These are commonly termed lmultistage units the number of stages depending upon 4tlie"'r1urritier"of'fan wheels used. When this is done it becomes necessary .that the air pass through the center and out of -*the Aperiphery of the'iirst fan wheel and-then he `"direetedback into'thecenter 'of the second wheel and "so don until `'the periphery of the last wheel is reached. The result y'of this construction is to increase the static suction or closed water lift but, at the same time, the volurneof air passing through the machine will be materially reduced.

The present invention is directed 'to a novel form of centrifugal 'fanwhee'l which is Vcapable of vproducing in a single wstage ymachine -a relatively Vhigh static suction 'as well'as a "relatively high volume wherebythe saine machine-may have its end uses multiplied considerably, iijer., a'machine embodying the present invention will be :usable "for 'any purpose whether a 'high volume or a high static A-is desired In view of the foregoing it is therefore Vone of the 'principal vobjects of the present invention to provide a 'centrifii'gal fa'n wheel which is capable of producing a relatively high static 'suction and arelatively high volume in a'single stage vacuum cleaner.

Another object of the invention is to Y'provide a centrifugal fan wheel for use in either vacuum :producing machines or blowers which will produce a higher static condition in a singleist'age machine "than in a multistage 'machine of the same size presently in use and which will also produce a'hig'her volume `than the volume type machines presently in use. n

A further object of the invention is to provide'a centrifugal fan Awheel which includes apair of axially spaced disks wherein a plurality of blades having an involute form lare kdisizvfose'd vbetween thosel disks.

A still 'further object Vof the invention is to provide fa centrifugal 'fan wheel wherein two disks 'are spaced apart iin an axial direction with a plurality yof blades located between the disks and wherein each blade is yin the form of an involute and arranged around the wheel with the 'center of the generating circle vfor the involute `being noffset from the center of the wheel. v

Still another object of the invention is to provide a centrifugal 'fan wheel fora compressible'fluid wherein a `plurality of involute blades are disposed between two flat disk-s. These blades are soarranged around the wheel that the inletarea 1between adjacent blades at the inneror heelends thereof is ygreater than the outlet area between `adjacent vblades at 'the outer or tip ends thereof whereby the iluid passing `through the space between adjacent blades `will be compressed.

yStill further and speciic object of the invention is to provideialcent'rifugal fan wheel adapted for use with coin- "pre'ss'ible fluids wherein a plurality of blades of involute formare 'equally lspaced around 'the wheel between two at disks and wherein the center of the generating circle for each involute blade is offset from the center of the wheel approximately the radius of the generating circle. It is also a specific object of the invention to form the involute blades 'using a generating circle having a diameter approximately one-sixth the Idiameter o'f the fan wheel -forrned by `the ydisks lbetween which vthe blades are located Whereby to achieve proper length of air passage and proper' heel and tip angles to result in maximum static and'volume "conditions ina vacuum producing machine. Other 'objects and 'advantages 'of the invention will be- 'eine apparent upon reading the following description taken in conjunction with the accompanying drawings in which:

Fig. l is a perspective view of a fan wheel embodying the present invention;

Fig. 2 is a horizontal sectional view through the fan wheel taken along the plane of line 2-2 of Fig. l; and

Fig. 3 is a somewhat diagrammatic illustration of pairs of involute blades which have been generated from a generating circle of the same size as that of Fig. 2, but with the center of the generating circle at diiferent locations with respect to the center of the wheel.

The centrifugal fan wheel embodying the present invention has certain desirable characteristics all of which contribute in a measure to the improved result of being able to achieve a higher static suction and a higher volume with a single wheel than has heretofore been accomplished by the use of either single or multistage wheels. In designing the fan wheel disclosed herein there is illustrated the preferred characteristics although it will be understood that some of these characteristics may be altered within limits without seriously affecting the result.

For example, it was first determined by various tests that an involute was the best form of blade which could be used to achieve the desired results. When it is considered that the involute of a circle is a curve generated by the end of a string which is kept taut while being unwound from a circle, it will be understood that for a given diameter fan wheel it would be possible to utilize circles of various diameters. It is also possible to locate the center of the generating circle or evolute in different positions with respect to the center of the wheel and thereby obtain different results.

Consideration must also be given to the length of passage between the blades or to the length of the blades themselves because if the blades are too long the resulting increased resistance to the passage of air therethrough will adversely affect the results desired.

Furthermore, the angle of a tangent at the tip end of the blade with a tangent to the wheel at the point where the tip end of the blade terminates has a very definite cifect upon the results. For example, the greater the angle the more feedback will occur resulting in less volume and less static delivery. It follows that a smaller angle at the tip is desirable although the smaller the angle the greater will be the length of the blade resulting again in increased resistance to air flow.

Consideration must also be given to the fact that the air which enters at the center of the fan wheel is relatively rareed and it is therefore desirable that this air be compressed to a degree at the point of its outlet from the fan wheel. To achieve this result it was found desirable to have the inlet area between adjacent blades at the center of the wheel be greater than the outlet area between adjacent blades at the periphery of the wheel.

The use of a true center involute where the center of the generating circle or evolute is common to the center of the wheel produces a plurality of blades which are parallel throughout their length resulting in inlet and outlet areas between adjacent blades which are identical; therefore, no compression of the fluid can take place. Also, when this is done it has been found that the length of the blades create undesirable resistance thereby adversely affecting the result by decreasing the volume.

ln order to arrive at a blade design of an involute form where the blade was not too long, where the angle of a tangent at the tip end of the blade with the tangent on the periphery of the wheel at a point coincident with the blade tip would be small enough to reduce feedback of the air, and where the inlet areas between adjacent blades Awould be greater than the outlet area thereof, it was necessary to conduct many experiments using generating circles of varying diameters and locating the centers of the generating circles at various distances from the center of the wheel. It was found that for a fan wheel having a seven and one-half inch diameter the best results were obtained by using blades of involute form where the involute was generated from a circle or evolute having a diameter of one and one-fourth inches. It was also found that for a fan wheel of six inch diameter, best results were obtained by using a generating circle of one inch diameter to generate the involute form of the blades. With this in mind the diameter of the generating circle should be about one-sixth of the diameter of the fan wheel to be used in order to achieve both the highest volume and highest static delivery.

ln arranging the involute blades which were generated from the predetermined diameter of generating circle ground the wheel in such a manner to obtain minimum feedback, minimum resistance and desired compression of the uid, it become necessary to locate the center of the generating circle for each blade in offset relation with the center of the wheel. Various distances for the wheel center and various directions therefrom were attempted with the result that the arrangement of the blade shown in Fig. 2 was determined to give maximum results.

Having the foregoing in mind, reference will now be made particularly to the drawings and especially to Figi wherein it will be seen that the fan wheel is composed of the two axially spaced apart disks 1 and 2. The upper disk 1 is commonly called the back of the wheel whereas the lower disk 2 is referred to as the shroud. The back 1 is provided with a central opening 3 for the reception of a shaft and the shroud 2 has the central opening 4 therein to receive the compressible iluid such as air and direct it to the passages between the blades 5 as the wheel rotates in a counterclockwise direction as viewed in Fig.

Each blade 5 is formed preferably of sheet metal and takes the form of an involute curve. Fig. 2 represents the preferred embodiment of the invention and illustrates the location of the involute blades to achieve best results. It will be understood that variation in the specific location of each involute blade 5 may be made without effecting substantially the end results but the greater the variation the greater the result will be affected. This will be brought out more clearly hereinafter when specific reference is made to Fig. 3 which illustrates other locations of involute blades which are unsatisfactory.

The inner end 6 of each blade 5 is called the heel of the blade whereas the outer end 7 is called the tip thereof. Having in mind that the results with respect to both volume and static suction will vary depending upon the length of each blade, the inlet area between adjacent blades near the center of the wheel, the outlet area between adjacent blades at their tip ends, and the angle formed between the tangent to the involute curve at the tip of each blade with the tangent to the circle formed by the tips of the blades at the point where the tip of the blade meets such circle, all of these factors have been considered in arriving at the particular layout of the blades shown in Fig. 2.

Experiments were conducted using disks 1 and 2 having a diameter of seven and one-half inches. involute curves having various diameters of generating circles were tried and it was determined that the best results were obtained with an involute curve having a generating circle of one and one-fourth inches in diameter. Other experiments with other disks of different diameters indicated best results to be obtained by the use of involute curves having different diameters of generating circles. For example, when the disks 1 and 2 were six inches in diameter it was found that best results were obtained by the use of an involute curve having a generating circle of one inch diameter. In this way it was established that the preferred form of the invention should utilize an involute curve where the diameter of the generating circle is substantially one-sixth the diameter of the wheel in which the blades are to be used.

It will be noted in Fig. 2 that the blades 5 are laid Out in an involute form where the involute is generated 'afferente fntafjeicekwisedireetien. viewingthesinne-wheelfeiern f the l opposite side,==vth'e involutei bladeswold bei-generated in a counterclockwise direction. Thisfctfniustbeborne ein nmnd Lwhen'defining-tl1eflocation f ithe/ center Y of the Mgenerating #circle ffor u the -invlute -with respect "to =the "fcenterlofr the same wheel.

When l"the :centerof the generating fcir'clle isv coincident l-Withl'* thecenter `f the wheely Aandi-'the invlutev 'blades-1 are fforined 'inispaced apart relation, git'vvilll be evidentthat all fof vtherelades Iwill-beparallel throughout their-#entire lengthinffaccordance with1the`blades` 8 in Fig. 3. This arrangement 'does not Esatisfy itwofof the requirements mentioned above, namely, *that the inletfareafb'etween adjacent Ablades/be :greater thanfthe foutletiarea. "'Where "the blades areparallel 1asfindica'ted by thefrlnmerallS the filet-andoutletfareas vwill be substantially identical so "that 'no compression `o`f1 theiiudewill''taketplace. VIt will salsoi 'be tn'oted-` that; the "length of='bla'c`tes -`8::is Aconsiderably Jgre'ater than the len'gthof'thefblades 'thereby/.resulting lin increasedvresistance'ito the' passage fof the :ui'd there- :between It was r thus 'discovered that fther fcenterr 'of the .generat- Ain'gvcirc'ile for the'invluteish'ouldvbe y'offset from thec'enter #of thefan wheel'a'nd experimentation -was V'then -necessary to determine thie .'amount of the foffset and :the l-dlrection thereof from the-center fthe wheel. When :.-speakingtdf 'the centerfof the generating circle. being-offset tf1-om the .'centeno'f theifan wheelasfused herein, iitis understoodto"meanrthat v.the initial positionfof .the genlerating ."circle 'is `:that vat which the :starting :point of :the involutei is'at: the' left ofthe center ofthe ygenerat-ing circle and :inra .position tozg'enerate the involutein Ia clockwise tdirection.

:Fig 3fillustrates the results Iof'threexpositions of the :generating circle all of Vwhich produce Aunsatisfactoryresuits. 'The :positioning ofthe *generatingcircle-so'tlrat --the center 'thereof Ais. coincident with the center'of the .fan -Ywheel ihas :already been vmentioned above .and was ,described asgresulting in the parallel'iblades f8. When, however, the center of the=generating circle y'is moved toward -thelefttof the center of the fan -wheel va distance equal -to the radius of 'the generating circle :so `that the `starting t points -of all of-the :involute blades will be on :at circlexha-ving .a 'radius twice that of the generating circle, -t-hes-result fwillbe toproduce blades like those indicated by :tlrenume'ral'9. It will, ofcourse, ebe'understood that for -each'blade :the generating circle is moved from-its initial starting, position-so that aflinegpa'ssing through therstarting tpointiof the vinvolute curve and the center "of the generat- :in-g circle willalso kpass through the center ofthe wheel. .fThus the dot-.dash circle indicated `by lthe 'numeral -10 viszthaton which :each .involute begins.

When adjacent blades are separated a distance of 36 degreesfso'thatitherewlllbea totltof ten L'biades for the wheel, it will be :noted that thefblades9practically touch at one. point along their length so thatair passing from the inlet 11 lbetween adjacent 'bladesto the outlet '1'2will go through a compression stage and ythen an expansion stage and the resistance thus offered for this reason and for the additionalv reason `that the blades are unduly long will produceivery'unsatisfactory results. The Volume will deini'tely'be decreased due to :the increased resistance and thus the objective -of maintaining bothhigh volume and lhighs'tatic conditions-will not-prevail.

When the position of the generating circle is initially as mentioned above and then moved toward the right of the center of the fan wheel a distance equal to twice the .radius of the generating circle so that the starting points of all involute blades will be on the circle identified by the numeral 13 the resulting blades will have the configuration of the blades indicated by the numeral 14. Again the blades 14 are spaced apart an angle of 36 degrees around a circle on any given radius from the center of the wheel to provide a total of ten blades only two of which are shown in Fig. 3.

l'and the 'tangent tothe-periphery-of the wheel atthefpoint where the blade tip 'meets the periphery is 'relatively` large 'duci'n'g'iles's volume. Y,

Further Vexperirnentation "indicated that positioning 'the generating-'circle of theinvolute Vtoward the `right of the center 'of'thewhel when thefgenera'ting circle `is `positioned sof'thatthe sta'r'tingfpcint er 'the "in'vclute is at the left of the center'of ythe'generatingcircle `and in afpositon to generate the .involute in aclockwise :direction produced improved results. -Thebestre'sultswere found to obtain when the generating circlewas moved Etowa'i-ithe righta -distanc'e :equal to theradius-of thatcircle and that`isth'e lposition 'of thef'blades 5 illustrated in Fig. `2. In this Vconlstructio'n the center of'thelge'nera'ting vcircle islocated 'at 'a point onthe c'irle C so thatthe starting point of the involute for all blades is at the center'C-of the fan'wheel. All-"of lthefdesired conditionsare met in thisl construction.

For example;itlwillbenoted that the lengthl ofy blades li5 is 'less'than the'flengthof blades'Sor v9"in Fig. f2 thereby satisfying one'requirementthat the blades ybe' 'of a length to create the'rninirnurn resistancefor iuid'ilow when the lotherfa'ctors Aare also considered.

Also, since the axial distanceib'etween vthe two disks `1 fand 2*"is'constar`1t'throughouttheir area thefdistance betweenblades 'at' their inletjandfoutletends will govern the inlet and outlet areas.y The inlet :area 7between :adjacent blaies 5 maybe governed by the distanc'ellrneasured on a perpendicularA lin'efro'rn the tangent at the'heelof one blade'to the next adjacent blade. Likewise;theoutletarea :between adjacent bl'ades f is governed by the "distance `O 'between vrblades 'measured on a perp'endicular Iline lfrorn 'the tangent at'the tip 'cf one 'blade 'to its adjacent blade. 'Thus ic'will he seen thatfthedistanee ris greaterthanthe distance O so that the outlet "area is less `than'the inlet area and a compression" 'of the viiuidwill result.

This arrangement also provides for a sinall'enough angle "between'thetangent at thetip of eaeh'blade andthe "tangent to the wheel'at the same point'so as to 'reduce leaklba'clc and thusinc'rease volume.

Obviously, the center 'ofthe generating circle maybe initially moved toward the right `of the center 'of the wheel under the conditions above'stated, varying distances to obtain'vaiying results. Ithis been establish'e'dfhowever, as is evident from viewing th'eblad'es 14 in Fig. 3 that tnev'ing thecenter cf the'gen'erating circle teward'the right a distance 'twice the radius 4of the generating circle -will give unsatisfactory v"results so that'it follows that'the 'distance toward the right which this center should be moved must 'be 'a 'distance less than twice 'the radius of the generating circle.

`itha's also been'established that 'when the centers of 'the generating circle and of Ythe wheclare coincident the result is also unsatisfactory a's 'isjevident from viewing the blades '8 'on Fig. 3 since the bladesare'parallelthroughout their entire length and are relatively long. Itithere'fore Afollows that for best results the center of the generating circle should be moved toward the right 'of the center A'of the wheel a distance less than twice the'r'adius of 'the generating circle and 'preferably a 'distance -equally substantially to the radius of the generating circle as illustrated in Fig. 2.

Although the fan wheel embodying the present invention may be fabricated in various ways, the preferred man` ner is to form each involute blade of sheet metal with a plurality of ears along each edge of the blade in spaced apart relation. Each of the disks 1 and 2 embodying the back and the shroud of the fan wheel is also provided with a series of slotted openings, adapted to receive the ears on each of the blades. Each series of openings in a disk for each blade will be located along the line of an involute of the same size as the involute used to produce the blades. The various parts are then assembled so that the ears 17 on each blade may extend through the corresponding slots on each disk. The ears 17 are then bent over against each adjacent disk whereby all of the blades are held in place in their proper relation positions.

Reference has heretofore been made to the static suction or closed water lift obtainable by the use of a fan wheel embodying the present invention as illustrated in Figs. 1 and 2. In actual practice it has been found that a fan wheel having a seven and one-half inch diameter with ten involute blades spaced equally around the wheel having a generating circle of one and one-fourth inch diameter and offset according to the arrangement of Fig. 2 will produce a closed water lift of approximately sixtyseven inches. It has not been possible heretofore to achieve that amount of closed water lift with a single stage fan having a diameter on the order of seven and one-half inches. The volume obtainable in the present fan wheel is not reduced below that which would be obtained by any other single stage vacuum producing machine. Such other machines, however, in order to acquire a closed water lift of sixty-seven inches would have to be provided with a plurality of fan wheels thus causing a considerable reduction in the volume obtainable. The present invention therefore results in unusually high static suction and volume in the same machine with the use of but a single fan wheel.

It will be evident also that the number of blades used might vary with varying results although it has been found that anywhere from eight to twelve blades will produce satisfactory results, the number of blades being shown herein for purposes of illustration being ten.

Changes may be made in the form, construction and arrangement of parts from those disclosed herein without in any way departing from the spirit of the invention or sacrificing any of the attendant advantages thereof, provided, however, that such changes fall within the scope of the claims apended hereto.

T he invention is hereby claimed as follows:

1. A centrifugal fan wheel comprising at least one disk, and a plurality of blades of involute form disposed on said disk and secured thereto, the center of the generating circle for each involute blade being offset from the center of rotation of the wheel.

2. A centrifugal fan wheel comprising two disks in axially spaced relation, and a plurality of blades of involute form disposed between said disks and secured thereto and arranged to be equal distances apart on any given radius from the center of the wheel, the center of the generating circle for each involute blade being offset substantially the same distance from the center of ro tation of the wheel.

3. A centrifugal fan wheel comprising two disks in axially spaced relation, and a plurality of blades of involute form disposed between said disks and secured thereto, the center of the generating circle for each involute blade being offset from the center of rotation of the wheel a distance less than the diameter of said generating circle.

4. A centrifugal fan wheel comprising two disks in axially spaced relation, and a plurality of blades of involute form disposed between said disks and secured thereto, the center of the generating circle for each involute blade being offset from the center of rotation of the wheel a distance substantially equal to the radius of said generating circle.

5. A centrifugal fan wheel comprising two discs in axially spaced relation, and a plurality of blades of involute form disposed between said disks and secured thereto, the center of the generating circle for each involute blade being offset toward the right from the center of rotation of the wheel when the starting point of the involute curve is at the left side of the generating circle and the curve is generated in a clockwise direction, the amount of said offset being substantially equal to the radius of the generating circle.

6. A centrifugal fan wheel for compressible fluids comprising two disks in axially spaced relation, one of said disks having an inlet opening at the center thereof for the passage of uid, and a plurality of blades of involute form equally spaced around the wheel and between said disks, the center of the generating circle for each involute blade being offset from the center of rotation of the wheel, and arranged so that the fluid inlet area between adjacent blades at the heels thereof is greater than the fluid outlet area between adjacent blades at the tips thereof, whereby the fluid will be compressed during the passage thereof between the blades.

7. A centrifugal fan wheel for compressible uids comprising two llat disks in axially spaced relation, one of said disks having an inlet opening at the center thereof for the passage of fluid, and a plurality of blades of involute form disposed between said disks and secured thereto and arranged to be equal distances apart on any given radius from the center of the wheel, the center of the generating circle for each involute blade being offset from the center of rotation of the wheel, and the distance on a perpendicular line from the tangent at the heel of any one blade to the next adjacent blade being greater than the distance on a perpendicular line from the tangent at the tip of said adjacent blade to the first blade, whereby the uid will be compressed during the passage thereof between the blades.

8. A centrifugal fan wheel for compressible fluids comprising two flat disks in axially spaced relation, one of said disks having a fluid inlet opening at the center thereof, and a plurality of blades of involute form disposed between said disks and secured thereto and arranged to be equal distances apart on any given radius from the center of the wheel, the center of the generating circle for each involute blade being offset from the center of rotation of the wheel, and the area of the inlet opening between adjacent blades being greater than the outlet opening between said blades, whereby fluid will be compressed during the passage thereof between the blades.

References Cited in the file of this patent UNITED STATES PATENTS 2,165,808 Murphy July 11, 1939 FOREIGN PATENTS 23,234 Germany July 23, 1883 115,070 Great Britain Apr. 22, 1918 121,052 Great Britain Dec. 5, 1918 297,661 Great Britain Sept. 27, 1928 338,436 Germany Aug. 29, 1920

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Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3144204 *Aug 24, 1962Aug 11, 1964Acme Engineering And Mfg CorpCentrifugal blower wheel
US3225422 *Mar 9, 1962Dec 28, 1965Ametek IncMethod of fabricating centrifugal fan impellers
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US3707336 *Nov 27, 1970Dec 26, 1972Hollymatic CorpFluid engine
US4253798 *Aug 8, 1978Mar 3, 1981Eiichi SugiuraCentrifugal pump
US4666373 *Mar 18, 1986May 19, 1987Eiichi SugiuraImpeller for rotary fluid machine
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US6340291Dec 10, 1999Jan 22, 2002Lothar ReckertHigh pressure impeller with high efficiency for small volume flows for radial blowers of different size
US6343773Jan 21, 1999Feb 5, 2002Shop Vac CorporationSupport structure
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US6695038 *Jul 15, 2002Feb 24, 2004Advanced Rotary Systems, LlcHeat exchanger type fan
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US8257043 *Jun 4, 2007Sep 4, 2012Hitachi Industrial Equipment Systems Co., Ltd.Multiblade impeller
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Classifications
U.S. Classification416/186.00R, 416/185
International ClassificationF04D29/30
Cooperative ClassificationF04D29/30
European ClassificationF04D29/30