US2711283A - Reversible flow fan - Google Patents

Description

June 21, 1955 E. R. TROXELL, JR 2,711,283

REVERSIBLE FLOW FAN Filed May 20', 1950 INVENTOR wzmag ATTORNEY EDGAR R.T2oxan.1.,JR.

REVERSIBLE FLOW FAN Edgar R. Troxell, Jr., Bronxville, N. Y. Application May 20, 1950, Serial No. 163,286 3 Claims. Cl. 230-42) My invention relates to means and method of room ventilation and particularly as applied to overhead window ventilators for ofiices, although .generally adaptable to any window, transom, doorway or other suitableopening.

At present in most spaces having double hung windows,

ventilation is attempted by raising the lower sash a short distance, with or without a so-called window guard. Such opening, being in or near the breathing zone, is neither the properlevel at which to admit outdoor air, except perhaps in warm weather, nor, at any time, the level at which smoke, odors and vitiated air can best be expelled. As is well known, this method is dependent upon outside wind pressure which, in different directions, either causes draftsfrom the crack opened between the upper and lower sashes, as well as the opening itself, or draws air out at these points. In the latter case, the replacement air may come from an unsatisfactory source and a large amount of heat be lostwithout producing the desired ventilation of the space. In any case, this method is fundamentally unsound in principle as it (1) causes drafts in cold weather, (2) leaves a blanket of warm, vitiated air pocketed above the openings, and (3) lacks definite control. 7 p p Means and method, according to my invention, are primarily for positive, winter ventilation although adaptable also for summer ventilation as well as for distributing and diffusing conditioned air.. The primary action of my device is to draw in, mechanically, a controllable amount of untempered outdoor air and spread it horizontally in a fan shaped stratum or spray near the ceiling of the space served. At the same time, by mechanical means as well as by induction,-to spread a similar, separate stratum or spray or blanket of room air immediately under the stratum of outside air. If the upper stratum is colder, and hence heavier, than the underneath stratum of room air, the former must and 'will fall and, in so doing, commingle and diffuse with-the room air before reaching the breathing zone.

It is emphasized that by the use of the means and method of my invention the introduction of air at a lower temperature than that of the room or space served, is made positive and controllable and that its action, by blanketing the colder. air introduced, with a separate stratum of warmer airunderneath, prevents the colder air falling before being completely commingled and 'diffused withthe room air. Also that thefluse of my device, by drawing in a controllable quantity of outdoor air and projecting it, at controllable velocity,in a fan shaped stratum or spray in a horizontal direction near the ceiling of the space served, gives wide distribution and thorough diffusion of the air used for ventilation.

In such spaces as this device is designed to serve, it may be desirable at times to exhaust heat, smoke, odors or vitiated air from the upper strata of said space. As a matter of fact, alternating supply and exhaust action may well be found the most satisfactory method of securing desired results, particularly in warm weather when other windows are open but when there is little or no nited States Patent smoke, odors etc.

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natural'air movement. To that end, in this device according to my invention, a revolvable inner fan-housing, manually turned to its I alternate positions, accomplishes this complete reversal of air movement," viz., supply or exhaust. To accomplish these results, I provide a motordriven, double disk-type centrifugal fan in a suitable twoway housing, fastened to a conditioned airduct oradjacent the, top of a window which is opened sufficie'ntly for the purpose. A revolvable inner fan-housing, in o ie position, provides discharge of air drawn from outside, either from a duct or from outdoors, as the case may be,

into the room in a fan shaped stratum. Simultaneously,

it provides for discharge of a similar separate fan shaped stratum of room air immediately under the first mentionedstream. v a Q Thus a device according to my invention' provides (1) means for introducing artificially chilledair or untempered outside air into a space without drafts, (2) utilization, in cold weather, of waste heat which otherwise stratifies at the top. of a room, (3) more uniform heat distribution in a space, and (4) thorough distribution and diffusion of the air used for ventilation; V

When the revolvable inner fan housing is manually turned to its alternate position, air fromthe. top of the room is positively exhausted outdoors when the .device is properly arranged at the top of a window, to remove A device ofmy invention comprises-an outer flat, boxlike housing, a motor of controllable speed-a'flixed thereto having a shaft extending vertically into the'housing, a centrifugal fan mounted on said shaft, said fan having a central separationdisk at right angles to the motor shaft, with blades mounted thereon, above jand below said disk, so as to provide two separate streams or stratums of'discharged air, one above'the other, and permitt n two separate intakes to said blades, one from-above and the other from below thefan disk.

Within said outside housing is an inner housingcomprising a semi-circular member surroundingapproximately one-half of the periphery of said fan, and revolvable through 1.80 degrees to provide either (1.) dischargeof air from both sets of blades into the room. or -(2) discharge of air from both sets of blades through a portion of the outside housing into the'outdoor air. In both instances, the lower set of fan blades draws air from the upper part of the room through a. grille forming a part of the lower face of the fan housing. Intaketo the upper. set of fan blades is determined by alsecondsemicircular member of the revolvable inner fan housing. This portion is fixed to but diametrically opposite the first named member and extends vertically betweena plane near the top of the upperfanblades and the topplate of the outer housing. f i e p The'fun ction of the inner housing is such that, in one position, it causes bothsets of fan blades to discharge air into the room, the upper'blades drawingv airthrough a portion of the outside housing from outside. ,Manually effective means and method for the. ventilation of small I ofiices and other rooms having outside windows.

A further object is to provide positive controlled ventilation without draftsusing tempered 'or. untemperedtor outdoor air.

. Another object of the present invention istoprovide a centrifugal fan contained in a two way, two part housing.

one part of which housing is revolvable within the other to regulate and control the direction of intake and of disr I V 3 charge of air by'thefan for the purpose of either supply or'exnaust of air.

Still another object is to provide means whereby outside air projected into a space by the fan may be blanketed l ath'f'ro'ri'ithe livingzone of said space with a sepanargeb thefan, "of'air taken from the top of the jlf, th 'erebylforciiig'the outside air to conimin gle' th pace airbefo're'reaching'the breathing zone of the A Astillfurther object of my invention is to' provide a fan andhoils ing" there'for'such that outside tempered or undairdischarged int'o'a space may be raised in temre'bywaste heat otherwise Stratified in the upper "of the space 'its'elf'a'nd commi'ngled with space air teachin the breathing 'zone or the space. the foregoing and other objects in view, as will be tjtojthjose'i'skilled in the artas thedescription proceeds, my invention resides in the combination and arrangement of parts and in the details of construction dfintlie specificationand particularly pointed out I 'peiided claims, it be'ing'underst'ood thatchanges' in theparticul embodiment of my invention may be made within"the1 scopeof what is claimed without departing fromjthe spirit of theiuvention. I intend no limitation otiferthan those of'the claims when fairly interpreted in the light of the full disclosure and the present state of the art.

"Referring now' to the accompanying drawing illustrativeof a'pref'erred embodiment of my invention,

Fig. I is a sectional side elevational view showing a form of ventilator arranged to draw in' 'and disassemfside air;'Fi'g. 2 is asectional view similar to Fig. l with thsame ventilator arrangedto exhaust inside air; Fig. 3 is a perspective sketch illustrative of the inner revolvable housing; Fig. 4 is a side elevation of the part shown in Fig. 3; Fig. 5 is a bottom view of the fan housing, with motor removed; Fig; 6'is a'fragmentary top view showing thefan air cut-'ofi operable on exhaust operation; Fig. 7 illustrates in elevation a complete window installation viewed from the space served. 7

Similar reference numeralsrefer to similar parts in the s ra ,v cw

"Turning now to Figs. 1 and 2, a motor 19 is arranged to drive a centrifugal fan 9 having a central disk 8 and positioned withina flat boxlike' housing 7 open at both ends, 'on the'lowerfside of which are air inlet openings 6, 6 (Fig. 5). Within the housing 7is an inner circular re-. volvable housing 5 contained and guided in part by the turned-in lips 4 of the top and bottom plates of housing 7 and in part by a pivot 19' extending through the top plate "t h usin 7 f i This inner housing comprises two diametrically opposite semi-circular bands or rings 2 and 3, open top and bottom,the' upper band 2 being axially offset from the lowerband 3, said lower band so arranged as to partially encircle the periphery of fan 9 so as to direct the fan discharge as desired and the upper band 2 arranged to determinefrom which direction the air flows to the upper fan blades. A stiffening member 11 is provided across the diameter of the revolvable housing 5. An operating handle 12, whereby the housing 5 may be revolved 180 degrees, extends from the two bands through the outer housing 7 as indicated (Fig. 5 A further stitfening member lies across the open ends of band 2 providing a member through which the pivot 19 passes.

The outer housing 7 has a vertical dimension greater than the width of the fan, preferably twice the fan width, the intake space 13 above the plane of the top face of the fan arranged for flow of air from either end of the housing to the upper face of the fan. In operation, the upper band 7 or baflle is positioned either to seal off space 13 from the room air (Fig. l) and open it to pass outside air or (Fig. 2) to seal off space -13 from the outside air and open it to pass room air to fan 9. At the same time, the diametrically opposite lower band 3 completes the enclosure of fan 9 in such way as to open the fan discharge to the area sealed off from intake by the upper band 2, as clearly indicated in Figs. 1 and 2.

Preferably, for window ventilation, the outer housing is supported as with screws 14, 14 to theppper part of the window casing 15. Telescoping side closure strips 18, 18 (Pig. 7) are provided, affixed -as wingmembers to the housing 7, the upper sash 16 being lowered and weather strips 17seal any cracks thus formed. 0

Preferably, also, the lower plate 1 of the outer fan housing 7, to which motor 10 is afiixed, is a separate cast or stamped member or grille or a portion of it is so constructed, thus providing a separate removable sub-assembly comprising grille, motor and fan. It will be noted that for "greater discharge efficiency of the fan when the ventilating deviceis acting to exhaust air from the space served (Fig. 2),"a cut-cit 21 (shown in Fig.6) is provided within the' housing 7,'the edge of the housing or the edge. of band 3 acting as a cut-off when discharge is to the space.

Wh'atIclaim is: l l i 1. A ventilator comprising a housing having top, bottom and end portions,'driving nieans mounted on saidhousing and having a rotatable shaft projecting thereinto, a centrifugal impeller having blades and mounted on said shaft within said housing, a solid 'disc forming a part of said impeller bisecting each blade and dividing the impeller into upper and lower substantially identical sections, said housing including an opening in each or the opposite end portions thereof, baflie means for said openings disposed within said housing and movable about'the axis of said shaft and means to operate said baffie means whereby alternate upper and lower portions of said openings are open or closed by said bafiie means, said upper portions to flow of fluid to said impeller and said. lower portionsto tangential flow of fluid from said impeller.

2. A device according to claim 1 wherein said impeller has a central intake above and below said disc and has an axial width of 'subst'antially one-half that of the casing measured between the top and bottom portions.

3. A device according toclaim 1 wherein said baffle means comprises two semi-cylindrical portions disposed one above the other and joined at their open ends, the lower portion of which is of substantially the same width as sa impe Refferences Cited'in the file of this patent UNIT ED STATES PATENTS 336,194 Graves etalt- Mar. 2, 1886 929,767 Hubbard Aug. 3, 1909 1,019,818 McMurdie r 'Mar. 12, 1912 1,055,487 Papin Mar. 11, 1913 1,554,914 Guthier Sept. 22, 1925 1,937,483 Shurtlefi Nov. 28, 19-33 2,185,614 Whitfield Jan. 2,-1940 2,205,902 McMahan June 25, 1940 2,265,317 'Schlirf Dec. 9, 1941 2,337,325 Hach Dec. 21, 1943 2,363,191 Miller Nov. 21, 1944 2,373,496 Paiste Apr. 1-0, 1945 2,373,497 Paiste Apr. 10, 1945 2,398,627 Disbro' et al.- Apr. 16, 1946 2,523,933 Akester et a1 Sept. 26, 1950 2,525,395 Boemer Oct. 10, 1-950 FOREIGN PATENTS 190,492 Switzerland Apr. 30, 1937 596,328 Great Britain Jan. 1,

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