Air diffusing device

April 28, 1953

2,636,668

H. A. MEYER ET AL

AIR DIFFUSING DEVICE

Filed Sept. 9, 1950

SHEETS—SHEET 1

<img file="US2636668A_D0001.tif" />

H. A. MEYER ET AL

AIR DIFFUSING DEVICE

April 28, 1953

Filed Sept. 9, 1950

2,636,668

SHEETS—SHEET 2

<img file="US2636668A_D0002.tif" />

<img file="US2636668A_D0003.tif" />

Patented Apr. 28, 1953

2,636,668

UNITED STATES PATENT OFFICE

2,636,668

AIR DIFFUSING DEVICE '

Harry A. Meyer, Detroit, and William .McCracken, Farmington, Mich., assignors to American Blower Corporation, Dearborn, Mich., a corporation of Delaware

Application September 9,1950, Serial No.183,928 (Cl. 230—274) • / :2-.

shown in dotted lines, forming .part of a heat exchanger. .

Fig. 2 is a side .elevation,-as indicated by the line II—II of Fig. 1 .showing the operative loca6 tion of our diffuser’relative to a fan.

Fig. .8 is a view in-.front elevation of the main plate of,our diffuser with-certain .baffle members shown.in Fig. 1 omitted.

Fig. 4 is a view .in .rear elevation ;of our diffuser. 10 -Fig,·. 5 is .a side elevation as indicated by V—V on Ejg. 4.

Fig. ,6 .is a-section on the line VI—VI of Fig. 4.

Figs. 7, 8 and 9 -are detail views showing the construction,of certain vanes located on the rear 15 face of our diffuser, Fig. 7 being on the line Vy—Vy of Fig. 4.The embodiment of our invention shown in the .accompanying .drawings comprises a rectangular-substantially flat-plate I made ,of suitable 2o metal having sufficient rigidity to maintain its rectangular and flat form. This plate 1 is formed with a surrounding flange 2, at right angles to the plane of the ,-plate and 'located preferably on the face of the plate which is disposed toward the 25 fan in connection with which the diffuser is used. This face of the ..plate may be termed the inner face, or upstream face of the .plate as it is this face which initially receives the -air blast or stream which it is. desired to diffuse or distribute 30 in the room or other .space-into which the air propelled by the fan .is to -be delivered.

At .each corner or angle of the plate I is located an outwardly projecting .stud holt 3, preferably welded to the plate so .as to be .rigid therewith. 35 These stud :bolts prdvide means for securing the diffuser in the air outlet opening 4 of .a casing wall indicated at ‘5 -in Figs. 1 .and 2 of the drawings. The .plate I is .preferably located against the inner face of such casing wall'5 and-is held 40 in place .by 'clamping washers and nuts .6/1 on said bolts :3 and overlapping the outer face of the wall ‘5.··, The pldte T is formed with a plurality Of slots :8 for pa'SSage therethrotig'h of the air stream'from'the fan and dividing said stream 45 into a ’plurality of -parts nr portions. .These slots are arranged in a plurality of groups, in the present embodiment, being four in number. As shown, each group comprises 'five such slots '8 which are parallel to each other in each group 50 and 'to a-side'edge or perimeter of the plate, said slots in «each group increasing ‘in length from the innermost «slot -at the central portion nf the plate , to the-outermost slot of the group, ait the side edge of the plate, the several groups of slots 'being 55 separated from each other by diagonal zigzag poitions -'B of the plate. It will he «seen that each of these groups of slots is substantially triangular in form with the apex formed by the shortest slot, disposed -adjacent the central area of the

Claims.

Our invention relates ibroadly and generally to mew and useful improvements in air diffusing devices, and more particularly contemplates a unitary device which is adapted to be associated .with, or assembled in connection with an. ah* propelling fan for the purpose of intercepting the blast or stream of air delivered by a fan and thereby diffusing or spreading the air blast or ..stream in the room or other space served by the fan.

The invention particularly contemplates :a .device .which will be efficient and simple in construction, and which may be located close to a fan and directly in front of and in a plane transverse to the blast or stream delivered :by the fan, •and will function to transform such .blast or stream from a .relatively high velocity, welldefined helical form in which it is projected from the fan, into a broader form or stream of relatively lower velocity so as to he spread and distributed throughout the space into which it fs delivered instead of being projected through a limited portion of the space directly in front of the fan, or against persons or objects, located in such limited space.

The invention is capable of many uses in connection with apparatus wherein a fan is employed for propelling ;a .stream of air into a room space and it is desirable to disperse or spread the. stream as delivered from the fan, but it will be found particularly desirable and efficient in connection with or as part Of heat exchange apparatus Of the circulatory or 'return type wherein'such apparatus includes provision for attempering room air, and also includes a motor driven fan of the propeller type which operates to .circulate room air into heat exchange relation'to such provision .and deliver the attempered'air to the 'room, this operation being continuous to maintain desired temperature of the air in the room. Certain apparatus of this general type is sometimes located overhead and operates to deliver the circulated air from the apparatus downward into the room, in connection with which type our invention will be found particularly useful. In the type just mentioned, a.diffuser embodying our invention will serve to deflect the air blast laterally into the room space instead of directly downward and thus prevent objectionable air blast directly onto persons or objects which may be located in the area beneath the exchanger.

The invention consists in the improved construction to be more fully described hereinafter and the novelty of which will be particularly pointed out and distinctly'claimed.

In the accompanying drawings, we have shown a preferred form of our invention, and wherein: .Figure 1 is a front view of our invention 'Showing the same assembled in relation to a fan

2,636,668 plate and the base formed by the longest slot adjacent a side edge of the plate so that said groups are located in sector-like arrangement around the central portion of the plate and are separated from each other by the zigzag diagonal portions 9 of the plate.

Along the inner edge of each of the slots 8 is an outwardly directed flange IS located on the downstream or outer face of the plate when in operative position, said flanges serving as· deflectors against the rear faces of which the air passing through said slots 8 from the upstream side of the plate strikes and is deflected laterally outwards toward and beyond the perimeter, of the plate. The flanges are coextensive with the edges of the slots so that the deflected air from the groups of deflectors is caused to take a generally pyramidal' form, the cross sectional area of which is fixed by the angle at which the flanges are made to the plane of the plate, and to the axis of rotation of the fan in connection with which the diffuser is employed.

It is to be noted that the groups of slots are so arranged that the slots and deflecting members of each group are at an angle to the corresponding slots and members of the next adjacent groups, and in such manner that starting with the innermost slot and member of one of the groups and proceeding clockwise as shown in Figs. 1 and 3, in a continuous spiral-like direction, each slot and its deflector flange delivers air at its end portion across the portions 9 into the path of the air from the neai’est end of the slot next in the series, and against the back of the deflector of the second row of slots, and in a like manner from the second, third, etc. slots and deflectors toward the lateral boundaries of the plate i.

This arrangement provides for passage of an ample volume of air through the plate and in equalizing or distributing the lateral flow of air in all directions into the space into which the air is to be delivered. It will be noted that this result is effected by offsetting each group so that a central transverse line therethrough lies to one side of and parallel to the diameter of the plate. Furthermore, the arrangement assures of prompt or free flow of air through the plate, so that the resistance of the plate to the air is reduced to a point as will not create such back pressure on a fan so as to cause the driving motor to overheat.

The vanes i 9 are made by bending up the metal cut out in forming the slots 8 in the plate i.

Arranged on and secured to the rear face or upstream side of the plate 1 are a plurality of baffles 1 i which serve to intercept the air stream delivered by a fan and turn or guide the air downward toward and through the slots 8 in the plate I. There are two of these baffles for each of the groups of slots 8 said baffles for each group extending radially from the central portion of plate I to the flange 2, and across all of the slots in the group. Each pair of baffles diverge from each other from the inner ends thereof to the outer ends thereof, see Figs. 1 and 4, and each baffle for a group of slots diverges relative to the next adjacent baffle for an adjoining group of slots. These baffles are so spaced around the center of the plate and relate to the groups of slots as to cause the air from the fan to be delivered substantially in equal proportions to the groups of slots and cause a uniform discharge of air through the slots in all directions.

The baffles are curved concavely toward the direction of the rotating air stream delivered by the fan as shown at 12, and thus serve to turn the air stream toward the rear face of the plate and the slots 8.

The baffles are preferably secured in place by forming the inner ends thereof with bendable ears 13, inserted through slots IS in the central portion ία of the plate i and bent over to form a rigid connection, the outer ends of said baffles being secured to the said flange 2, by bendable ears 15 inserted through slots 16 in the flange, and bent over on the outer face of the flange. The ear (3 on each baffle is formed on the edge 13α of a triangular part 13b, which when bent over on the dotted line (see Fig. 9) brings the edge 13α into contact with the inner face of plate (, thereby bracing the inner end of the baffle and assisting in holding the baffle in the operative position described, when the ear 13 is bent over as indicated in Fig. 6. In Figs. 1 and 2, we have shown our diffuser assembled in an outlet opening 4 of the wall 5 of a heat exchange apparatus which for example, includes a propeller type fan 17 for propelling air through said opening, the fan being driven by an electric motor 18 and surrounded by shroud-ring ig, to direct the air toward the opening 4. It will be noted, from Fig. 2, that our diffuser constructed as above described, has the advantage that it may be located in close proximity to a fan, and that the air stream in helical form and moving in the direction indicated by the arrow in Fig. 4 will in part pass directly through the slots 8, and a portion of sucli stream will strike the baffles i i as indicated by the dotted arrows in Fig. 5 and be deflected to the groups of slots. The radial arrangement of the baffles I i also serves to cause the air to be directed toward the side edges of the plate. Thus the baffles ί I not only serve to equalize the delivery of air to the portions of the several groups of slots 8 located between said baffles, and to the groups individually with the result that there will be a substantially uniform discharge of air in all directions.

It is to be noted that the ah· issuing from each of the slots 8 in each of the groups of slots and deflected by the member 10 on the inner edge of the slot will be generally fan-shaped in form due to the fact that the air will not only flow outward from the central portion of the slot but will also flow laterally from the ends of the slots in a direction across the parts 9 at the ends of the slot. This is true of each of the slots 8 and its associated deflector i S. By arranging each of the slots of a group so that the delivery ends of the outermost slot of each group overlaps the adjacent delivery end of the outermost slot of one adjacent group, and the delivery end of the second slot in the other adjacent group, and in a like manner respecting each successive slot in each group, the air from the delivery ends of the slots in each group is delivered across the parts 9 and mixes with the air delivered by the ends of the slots in the next adjacent groups. This arrangement has the advantage of contributing to the equalizing of the air stream in all directions from the diffuser. Further, the arrangement provides for slots of ample width and length to enhance free flow of air through the diffuser and reduce objectionable back-pressure on the fan.