US3186329A - Tubular air diffuser - Google Patents

Description

June 1, 1965 w. w. KENNEDY 3,186,329

TUBULAR AIR DIFFUSER Filed May 21, 1962 3 Sheets-Sheet 1 IN VEN TOR.

ll d/er A flmedy BY h f w Udfim I ATTORNZSXS June 1, 1965 w. w. KENNEDY 3,186,329

TUBULAR AIR DIFFUSER Filed May 21, 1962 3,Sheets-Sheet 2 INVENTOR. li d/ter M ATWY/Yea/y BY (J Ifu AZM- J ATTORNEYS June 1, 1965 w. w KENNEDY 3,186,329

TUBULAR AIR DIFFUSER Filed May 21, 1962 3 Sheets-Sheet 5 INVENTOR.

ll d/cr /1. Kennedy BY dick flu ATTORNEYS United States Patent 3,186,329 TUBULAR AIR DIFFUSER Walter W. Kennedy, Rockford, Ill., assignor to Barber- Colrnan Company, Rockford, 1th, a corporation of Illinois Filed May 21, 1362, Ser. No. 196,366 Claims. (Cl. 98-40) This invention relates to a tubular type diffuser mounted in the end of an air duct for universal adjustment to determine the angle of discharge of the air stream delivered through the duct.

The general object is to provide a diifuser of the above character which, as compared with prior constructions, is simpler and less expensive to manufacture and which, for a given axial length, provides for a wide range of adjustment of the discharged air stream.

Another object is to provide for greater angular adjustment of the discharged air stream than has been possible heretofore without substantially shortening the range of throw of the stream for a given discharge velocity.

A further object is to utilize a novel arrangement of concentric tubes to achieve the foregoing objects.

The invention also resides in the novel sizing and mounting of the tubes of the ditfuser relative to each other and to the duct end.

Other objects and advantages of the invention will become apparent from the following detailed description taken in connection with the accompanying drawings, in which:

FIGURE 1 is a fragmentary elevational view of part of an air conditioning duct equipped with a discharge outlet embodying the novel features of the present invention.

FIG. 2 is a perspective view of the improved outlet.

FIGS. 3, 4 and 5 are sections taken respectively alonglines 33, 44 and 5-5 of FIG. 2.

FIGS. 6, 7 and 8 are schematic views through a diameter of the duct showing diiierent adjusted positions of the outlet unit.

FIG. 9 is an end view of FIG. 8.

The improved air diffuser is especially suited for use in factories, auditoriums and like installations where artistic appearance may be sacrificed to some extent in order to achieve a wide range of adjustment of the angle at which the air stream is discharged into the room and also convenience in changing the adjustment. Accordingly, the diffuser is shown in the drawings mounted in the outlet end of a cylindrical duct it) branching from a main supply duct 11 and adapted for universal adjustment to direct thedischarge air stream 12 at any angle relative to the duct axis within acone 13 having an angle of thirty degrees for example. Herein, the diffuser is secured to the duct end through the medium of amounting ring 14 of right angular crosssection having oneflange 15 telescoped with and fastened byscrews 16 to the duct end. A second and inturnedflange 17 constitutes a mounting plate for the diffuser and defines at its inner edge 18 a circular hole concentric with the duct axis and somewhat smaller in diameter than the duct.

In the form shown for purposes of illustration, thediffuser 9 comprises generally aring 21 journaled on the inner edge portion of theflange 17 to turn about the duct axis and, through the medium oftrunnions 22 supporting an axially elongatedtubular deflector unit 23 for swinging adjustment about a diameter of the duct and through the desiredangular range 13. In the present instance, thering 21 is composedof twoparts 21 and 21 formed around their edges withshallow ribs 25 which telescope as shown in FIG. 4 within thehole 18 of the flange and are held in face to face relation by angularly spacedscrews 26. The ribs are only slightly smaller in diameter than theflange edge 20 which thus provides a bearing in which the "ice ring is journaled for turning about the duct axis. The combined height of the ribs is slightly less than the thickness of theflange 17 so that with the screws tightened properly, the ring parts grip the flange under enough pressure to trict-ionally retain each selected position of the ring.

While thetrunnions 22 may be journaled in either thering 21 or theunit 23, the opposed faces of the ring parts are recessed at 28 in the present instance (see FIGS. 3 and 5) to provide diametrically alined sockets in which the outer ends of the trunnions are journaled but gripped under sufficient pressure to provide the friction necessary for retaining the selected angular adjustments of thetubular unit 23. Herein, the headed inner ends of the trunnions are secured rigidly as by welding 29 to the outercylindrical tube 30 with the two trunnions alined accurately. To allow for Wide angles of horizontal swinging of theunit 23 when several of the latter are disposed side by side, the trunnions are spaced substantial distances from the ends of the tube, being about midway between the ends in this instance.

To provide for discharge of theair stream 12 into the room at an angle corresponding closely to each angular position of thetube 30, additional and successively smallertubular deflectors 32 and 33 are arranged Within thetube 30 concentric therewith and rigidly secured thereto as byspokes 34 which may comprise radially extending rods welded to thetubes 39, 32 and 33 but are shown herein as relatively thin and flat and angularly spaced apart with their laterallybent ends 35 spot welded to the opposed surfaces of the adjacent tubes. The latter are substantially equal in axial length and radially spaced equidistantly apart, there being, in the present instance, three tubes 4% inches long spaced 1% inches apart in this instance for an air discharge outlet nine inches in diameter as determined by the internal diameter of thering 21 as compared with a duct diameter of twelve inches. For such a duct size and arrangement of the trunnions relative to theouter tube 30, the latter is preferably about 4% inches in diameter thus leaving an openannular space 37 between the tube and theinner periphery 38 of thering 21 and of uniform radial width when theunit 23 is alined axially with theduct 10 as shown in FIG. 6.

The lengths and number of theconcentric tubes 30, 32 and 33 employed in theunit 23 will be determined by the size of theduct 10 in relation to the desiredcone 13 of adjustment of the air streams. In each instance, it is desirable to correlate the lengths and radial spacing of the concentric tubes so that at the maximum angle of adjustment of theunit 23 about a diameter of the duct, the tubes will, as shown in FIG. 7, coact to substantially block and prevent a clear line of sight through the unit axially of the duct. Because of this, the surfaces of the tubes act as bafiles for deflecting the air stream flowing out of the duct and causing the same to be discharged into the room at an angle closely approximating that at which the unit is set.

Such accurate correlation between the angular position of thetubular unit 23 and the path of the dischargedair stream 12 is attributable to several factors and is achieved, I have found, in spite of the substantial width of theannular space 37 which is provided around the unit in order to allow a wide range, 60 degrees in this instance, of the unit. By virtue of the relatively close spacing of thetubes 30, 32 and 33, turbulence in the air stream as it enters the inner ends of the tubes is dissipated and a straight forward flow is induced by the action of the tube surfaces before the stream is discharged from the outlet end of the unit. A substantial volume of air flows out of the duct through theannular passage 37 around thetube 30 and generally along the latter, but, owing to jet action at the discharge end of the tubular unit, such air is drawn into themain stream 12 around the periphery thereof and without destroying the well defined shape thereof or reducing the length of the throw. For a given velocity within the duct, a substantially longer throw is achieved than would be possible if thetubes 32, 33 were omitted.

To produce a straight axial discharge of theair stream 12, the tubular unit is disposed with its axis coincident with the duct axis as shown in FIG. 6. In this case, theannular space 37 between the tube 39 and the inner edge of thering 21 is of uniform radial length.

As the unit is swung in either direction about the diametrical axis defined by thetrunnions 22, for example to the position shown in FIG. 8, the width of thespace 37 adjacent the trunnions remains unchanged but at other points around thetube 30, the space varies in width. In this position, it will be apparent that the outer surfaces (1 on one side half of each of thetubes 30, 32 and 33 are disposed at an acute included angle relative to the direction of air flow through the duct and thus become effective as baffles to intercept corresponding areas of the air stream forced through thering 21 and deflect such portions of the streams laterally causing it to be discharged into the room at an angle corresponding to the angular position of the unit. It will be noted that because of the spacing of the outer surface a of thetube 30 inwardly from thering 21, this surface also contributes to the deflecting action.

The inner surfaces b on the other halves of the tubes are inclined at the same acute angle and cause deflection of the remaining cross-sectional part of the air stream by an equal amount. At all points around theouter tube 30, air flows out of the duct thus by-passing thetubular unit 23 as shown by the arrows in FIG. 8 but, as pointed out above, such air is quickly aspirated into thestream 12 immediately beyond the tubes and does not change the angle of discharge or the length of throw of thestream 12.

The desired long range of throw of the dischargedair streams 12 and close correspondence between the angular position of thetubular unit 23 and the path of discharge of thestream 12 is maintained over the full 60-degree range of adjustment of the unit. This is attributable to action of the successively smallerinner tubes 32, 33 in substantially blocking the line of sight through theouter tube 30 thus preventing the development of turbulence within the latter and the consequence loss of velocity and control of the stream within the unit. Such blocking action is illustrated in FIG. 7 in which theunit 23 is disposed in one limit position with the inner and outer ends of thetube 30 in contact with thering 21 on diametrically opposite sides of the trunnion axis.

From the foregoing, it will be apparent that theplate 17 and one of the rings, for example 21*, together form an annulus covering the end of the duct and defining by its inner edge 38 a hole which is larger than the tube so as to permit the tube to be swung about the transverse axis defined by thetrunnions 22. At the same time, the trunnions are clamped frictionally by thescrews 26 against thering 21 whose annular shoulder 25 (FIG. 4) is journaled in theinner edge 18 of theplate 17. Thus, in

this instance, thetrunnions 22 and thering 21 form a connection between theannulus 17, 21 and the tube and support the latter for adjustment about the two perpendicular axes.

I claim as my invention:

1. In combination with a duct adapted for the flow of air axially therethrough, an annulus adapted to be secured to the end of a duct concentric with the duct axis, an elongated tube extending through the hole defined by the annulus and having an outer peripheral surface radially spaced inwardly from the inner periphery of the annulus, said tube receiving at its inner end air delivered through said duct and discharging a stream of such air from its outer end in a direction determined by the angle included between the axes of said annulus and said tube, and means connecting said annulus and said tube and supporting the latter for turning of the tube about the axis of said annulus and also for swinging about a transverse axis extending diametrically across said hole and lying substantially in the plane of the annulus, said connecting and supporting means including two trunnions projecting radially from opposite sides of the tube along said transverse axis and disposed intermediate the ends of said tube whereby to provide, in the different angular positions of the tube about its own axis, for swinging of the tube about said transverse axis as permitted by the space between the annulus and the tube.

2. An air diffuser as defined in claim 1 in which said trunnions are disposed about midway between opposite ends of said tube whereby to provide a wide range of angular swinging of the tube about said transverse axis.

3. An air diffuser as defined in claim 1 in which the different angular positions of said tube about said two axes is maintained by friction between .opposed surfaces in said connecting means.

4. An air diffuser as defined inclaim 3 in which said friction is derived from a clamping screw extending between a part of said connecting means and a part of said annulus.

5. An air diffuser as defined in claim 1 including a plurality of tubes successively smaller than and approximately the same length as said first tube, and spokes rigidly connecting each adjacent pair of said first and second tubes and supporting the same in concentric relation whereby air delivered into said first tube is divided into a plurality of concentric tubular streams each guided in its flow substantially throughout the length of the first tube.

References Cited by the Examiner UNITED STATES PATENTS 1,754,961 4/30 Neilson 9s 2,326,858 8/43 Honerkamp 98-40 FOREIGN PATENTS 165,081 9/55 Australia.

ROBERT A. OLEARY, Primary Examiner. EDWARD J. MICHAEL, Examiner,

Claims (1)

1. IN COMBINATION WITH A DUCT ADAPTED FOR THE FLOW OF AIR AXIALLY THERETHROUGH, AN ANNULUS ADAPTED TO BE SECURED TO THE END OF A DUCT CONCENTRIC WITH THE DUCT AXIS, AN ELONGATED TUBE EXTENDING THROUGH THE HOLD DEFINED BY THE ANNULUS AND HAVING AN OUTER PERIPHERAL SURFACE RADIALLY SPACED INWARDLY FROM THE INNER PERIPHERY OF THE ANNULUS, SAID TUBE RECEIVING AT ITS INNER END AIR DELIVERED THROUGH SAID DUCT AND DISCHARGING A STREAM OF SUCH AIR FROM ITS OUTER END IN A DIRECTION DETERMINED BY THE ANGLE INCLUDED BETWEEN THE AXES OF SAID ANNULUS AND SAID TUBE, AND MANS CONNECTING SAID ANNULUS AND SAID TUBE AND SUPPORTING THE LATTER FOR TURNING OF THE TUBE ABOUT THE AXIS OF SAID ANNULUS AND ALSO FOR SWINGING ABOUT A TRANVERSE AXIS EXTENDING DIAMATERICALLY ACROSS SAID HOLE AND LYING SUBSTANTIALLY IN THE PLANE OF THE ANNULUS, SAID CONNECTING AND SUPPORTING MEANS INCLUDING TWO TRUNNIONS PROJECTING RADIALLY FROM OPPOSITE SIDES OF THE TUBE ALONG SAID TRANSVERSE AXIS AND DISPOSED INTERMEDIATE THE ENDS OF SAID TUBE WHEREBY TO PROVIDE, IN THE DIFFERENT ANGULAR POSITIONS OF THE TUBE ABOUT ITS OWN AXIS, FOR SWINGING OF THE TUBE ABOUT SAID TRANSVERSE AXIS AS PERMITTED BY THE SPACE BETWEEN THE ANNULUS AND THE TUBE.

Images