US1408715A - Air-blowing device - Google Patents

Description

A; E. SEELIG AND V.'H. CAHPLES.

AIR BLOWING DEVICE APPLICATION FILED FEB. 24. I919.

Patentd Mar. 7; 1922.

Jlfrcei E )yealby wary. wp w TA PATENTCFFICE ALFRED n. SEELIG Am) vrcron H. can nes, on NEW roux, may) I Amasnowme, DEVICE.

, Applicat i on filed Februar 24, 1919.seia1'nb.'zia ,s95.

- which the followingis a specification.

blovving devices, and more particularly to This invention relates generally to air thati type, of blower in which the effective peripheral portion of the blade creates a hollow column of air substantially parallel to its axis, such blowers being generally known ashelicahfans or fans of the screw propeller type. Clurrent produeing devices of this general natureoperate with-a CQII1 paratively high degree of efiiciency but it hasbeen foundthat the rotationof the fan has the effect of producing'amovement not onlyin the desired direction along the axis ot'the pipe butfalso a radial and outward component of motion and, in addition, a rotating or swirling motion of thecurrent of airthat ispassing through the pipe. It will be obvious that the swirling motion thus given to the moving column of air detracts from the general. e'fliciency of operation of the device, since the rotary component o motion serves no usefuhpurpose, but renders ineffective apart of the whole energy of motion of the air current that should be 7 wholly directed in a useful direction toward the outlet end ofthe pipe. It has been further found that the creation of a radial component results in theformation of eddy cur rents that. swirl backward from the current issuing from the fan into the fan center where' they interfere with the normal operation o fithe device. A further obstacle; is found in the fact that the radial component adjacent the intake side of the fan is'thrown suddenly and violentlyoutwardly and that theblast of air created is a hollow column that tends to impinge on the walls of the pipethereby retarding movement of the fan blades, and which is somehow reformed into a solid column ot air filling the pipe The mainv object of this'invention is to provide an air blowingdevice of the character set forth in which the radial component created adjacent the intake side of the em shall, be gradually directed in an outward Specificationof Letters Patents Patented of Manhattan, in the city of New York,

direction "and then in a direction substantially' parallel were axis of rotation of the tan; 'and in which the, hollow column offiair ssuing fromthe discharge side of the fan will not appreciably impinge against the wallsof the pipe but will be gradually restored to a solid column, free of swirling motion and eddy currents and travelingin a direction the fan.

In accordance with the above the invention resides in the features of construction,

combination of parts and arrangement of elements hereinafter set forth and claimed.

parallel to theaxis of rotation of In the accompanying drawings thein- Y vention is disclosed in several concrete and preferred forms in 'which- F1gure-I is alongitudhal sectional View,

largely diagrammatic in character, of a de' vice embodying the invention in one form.

Figure 2 1s a View similar to Fig. l-with one of the-tan blades 1n sectionshowing a modified form'of thelinvention. Figure 3 1s av view in'perspective of th anti-swirling device, looking into the outlet end thereof, andadjacentelements, the pipe being indicated bya ring.

Figure4 is'a. VlBWlII perspective of the anti-svvirling deviceylooking into the inlet f end thereof, and adjacent elements, the pipe also-being indicated by a ring. y

Figure-his asectional view on line 5'-5 of Fig. 1 showingtheanti-swirling device in elevation. I

Figure 6is a perspective'viewofwthei fan and air guiding member at the intake side of the fan. i

1 indicates a fan of the helical or screw propeller type, thatis ofsuch a. character as to produce ahollow column of air. atthe effective peripheral portion 11 of its blades in a direction substantially parallelrto its axis and lengthwise of the casingor'pipe 2. To gradually direct the incoming air toward the effective peripheral portion of f the blades there is provided a central air guiding member 6 that rotates with the fan, is of less diameter thanthe latter and is disposed inrear of cutting edges 12 of the fan blades substantially throughout their length, said member having awsurface m,

as shown, faeingin'the same direction as the intake sideofthe fan and" a second surface 14 merging with the'first surface adconsists of ajnui'nber o f stationary blades as fishownprogecting from the 'memberfipsaid fan "ii-or directingtlie air currentin di rem shape.

tion substantially parallel to the axisof'rotation adjacent the dischargeside-iofsltherfi m The surfaces 13 and 14: may also be considthe hub of the fang Member '6; maytermt irate flush With the discharge side of the ran or may extend slightly; beydnd that point 4 Adj acen preferably beyondjtheplane, ras blades closely adij acent isl an air directing member ,for gradually permitting the hollow column of air to re form into a solid column moving 'infdirec tion parallel v to the "axis of rotation, Member 8 is of a diameter substantially fequal to that of member 6 at the. point where tl eir edges meet and sa d members are axially cor incident and are arranged-leach to back Wlth h ir dir cti g .s rf qe fe i s y xifir each other. Preferably member 8; .has an oge'e-sh aped surface, as shown, facing inthe same {direction 'as'the discharge side Q f lille fan. Members 6 1 and 8lmay-be one member and may both rotate iththe fail, but 11 13 erably 8 :is astationaryr-memberiwith its a back as closely adjacent the fan bladesj or the back of memher-.;6' as possible;

yAd-iacentthe o f the ianfis an anti-swirling device -35Whosegfunction :it is to-translate the swirling component of thei airj current into one substantial-1y para allel to the axis ofgrot'ation. This device "blades meeting the swirling air; and having substantially hehcal surfaces 4 at there 1nrtake. sides which suriia'ces gradually hange their direction until}they becfome straigl'it surfaces 5 at the outlet side of theidevice.

In order to prevent the current of air created by the fan blades from impinging "against the wall of thepipe or :c-asing, and

' thus -inter'fering with sthe efficient rotatipn I 'ofthe fan by creating 'eddyourrents, it is preferredrto, bend or curve thegouter edge of the zfanbladestoward theoutlet side of .ranaset'ztrig. 2). p p a I It rwill be understood ii'rom the foregoing that the'air isygradually guided from the central :portionpf the fan toward the periphery thereoifand theme in the form of a "hollow column-1n a 3 direction" parallel m the l axis'of rotation ;f and thatthe discharge air is prevented :fromfimpinging against the Wall of the casing, is gradually restored to asolid column and has its swirling co nponent eliminated. This tends to increase the A'convenient construction is shown; in the drawings in which member'G is prom vided with slits 15 forthe reception ofthe fan blades and suitable means, 'ass crews 16',"

' may be employed to secure sa-idme nber to the 'fan;

efllcifencyof the fan by avoidingunnecessary friction losses and preventing eddy currents a-ndblo-W backs. V l V whisp r-c im; r

1. An air blowing device comprising: a

ered as one surface of substantially" egee 'ripipe a ran having blades the'effective peripheral portion of Which createsa hollow "column oi air parallel to the axis of;rotation oi theian andlengthwlse of the pipe, said colunin'of air beliiig-cdmpmsed of a plurality 1 of components one of which is parallels uh the axis of rotation of the'ian anotherfoi [which is'radial'uith respectthereto and 'a third for which is swirling in "character, 'in'eans rotating with the fan for preventing against the Wallof the pipe by directing'iit lengthwise thereof, stationary =x'ne'ans atlthe outlet side of the "fan and ilrth'ejpath of the air current roe gradually translating the swirling; j'coinponent of the air current into one acting "in line substantially 'iparallel tolthe' a'xisof'rdtation ofthe. fan, and means 7 at the o utlet side of the fan for gradually translating the hollow column of as: f into a solid stream.

Jean-air blowingdeyice damaging: a

fa-1'1-;hav'ing blades the effective peripheral portion 'of whi'ch' oreates a hollow column of air substantially parallel to its axis, "and disposed' in rear of "the cutting edges ofthe bladess'uhstautially throughout their length, see member having "a surface facing in the same direction as the intake side of *fan' Qof a contou'r togradual'ly direct the iil'com Ling toward the effective peripheral portio'nof the fan, and aiseciond surface on saidmember adjacent the effective peripheral ion portion ofthe fan merging with the first surface and directing the air current in a dlrectioii substantiallyparallel to the axis of rotation acent the discharge side Pof the fan of less dia eter'than the latter and disposed in rear of the cuttingedges of the blades substantially throughouttheir length, said i member "having a substantially joge'eshaped surface facing in the. same direction as the intake side of the fan to gradually direct the incoming air toward the efieotive peripheral portionof the fan andthen" in a direction substantially parallel vto' the' axis of rotation of thei'an.

4. An air blow ng central air guiding member of less diameter p device comprising: a fanfhavi'ng blades the effective peripheral portion of which creates a hollow colu'mnof air substantially parallel to its axisga-nd a 110. air blowingdeiiice comprising z a fan having bladesthe effective peri he also the radial air component from impinging than the fan at the discharge side of said fan, said member having a substantially ogee-shaped surface extending away from the discharge side of the fan to gradually direct the air into a solid column parallel to the axis of rotation of the fan.

5. An air blowing device comprising: a fan having blades the effective peripheral portion of which creates a hollow column of air substantially parallel to its axis, a cen tral air guiding member rotating with the fan, of less diameter than the latter and disposed in rear ofrthe cutting edges of the blades substantially throughout their length, said member having a surface facing in the same direction as the intake side of the fan of a contour to gradually direct the incoming air toward the efiective peripheral portion of the fan and then substantially parallel to the axis of the rotation adjacent the discharge side of the fan, and a central air guiding member at the discharge side of the tan having a surface extending away from the discharge side of the fan to gradually direct the air into a solid column parallel to the axis of rotation of the fan, said guiding members being axially coincident and arranged back to back with their edges adjacent and of substantially equal diameter to form a substantially continuous opening for the passage of air.

6. An air blowing device comprising: a fan having blades the efiective peripheral portion of which creates a hollow column of substantially parallel to its'axis, a central alr guiding member rotating with the fan, of less diameter than the latter and disposed in rear of the cutting edges of the blades substantially throughout their length, and a central air guiding member at the -discharge side of the fan, said guiding members being axially coincident and arranged back to back with their edges adjacent and of substantially equal diameter to form a substantially continuous opening for the air guiding member rotating with the fan,

of less diameter than the latter and disposed at the intake side thereof, and a central air guiding member at the discharge side of the,

tan, said guiding members being axially coincident and arranged back to back with a their edges adjacent and of substantially equal diameter to form a substantiallycontinuous opening for the passage of air and" said members having surfaces to direct the incoming air outwardly at the intake side i toward the peripheral portion'of the fan, and inwardly at the discharge side into a solid column substantially axis of rotation of the fan.

8. An air blowing device comprising: a fan having blades the eifective peripheral portion of which creates a hollow column of air substantially parallel to its axisfan air guiding member facing in the same diparallel with the rection as the intake side of the fan dis-' posed in the plane of the'blades for gradually directin the air outwardly toward the effective peripheral portion, and a second air guiding member facing in the same direction as the discharge side of the fan located beyond the plane of the blades at the said dischar e side.

Signed at l ew York city, in the county of New York and State of New York this 20th day of February, 1919. a l

1 I ALFRED E. SEELIG.

VICTOR H. CARPLES.

Images