US3185067A

US3185067A - Slot diffuser

Info

Publication number: US3185067A
Application number: US136945A
Authority: US
Inventors: William L Batchelor
Original assignee: Allied Thermal Corp
Current assignee: Allied Thermal Corp
Priority date: 1961-09-08
Filing date: 1961-09-08
Publication date: 1965-05-25
Anticipated expiration: 1982-05-25
Also published as: GB1023693A; DK108463C

Description

W. L. BATCHELOR May 25, 1965 SLOT DIFFUSER 2 Sheets-Sheet 1 Filed Sept. 8, 1961 FIG 70 F/GI/O l/VI/E/VTOR 78 WILLIAM L BATCHELOR /wwy' filWM II w/ 14 7 ATTORNEYS May 25, 1965 w. L. BATCHELOR SLOT DIFFUSER 2 Sheets-Sheet 2 Filed Sept. 8, 1961 Fla/3 l/VVE/VTUR WILLIAM L BATCHELOR United States Patent 3,135,667 SLOT DH FUESER William L. ilatchelor, Newington, onn., assignor to Allied Thermal Corporation, New Britain, Conn, a

corporation of (Ionnecticut Filed Sept. 3, 1961, Ser. No. 136,945 il Claims. (Cl. 98-49) This invention relates generally to air diffusers and more particularly to air diffusers of the type herein referred to as slot diffusers for the reason that the air outlets are in the form of elongated slot openings.

It is a principal object of this invention to provide an improved slot diffuser that is adaptable for being installed within a ceiling or the like with its outside face flush with the surface of the ceiling and which is thereby particularly useful in building constructions where such installations are desirable in order to modernize the appearance of the ceiling and to facilitate the positioning of removable partitions or walls within the building.

It is another object of this invention to provide an improved slot difiuser which, though mounted flush within a ceiling or the like can emit the air along the ceiling efliciently and without creating turbulence directly below the diffuser outlet.

It is another object of this invention to provide an improved slot diffuser which uses a unique configuration of parts to efliciently dilfuse air into a pattern that can be conveniently controlled within a range of approximately ninety degrees.

It is a further object of this invention to provide an improved slot diffuser that has a simple arrangement of parts and which can be economically constructed without diminishing its utility or efllciency.

It is another object of this invention to provide a slot diffuser that is useful for a number of applications, as for example, in association with a conventional troffer light for diffusing air from along the lateral edges thereof or in association with a noise generator adapted to raise the background noise level within a room for increasing the comfort of the persons therein.

Other objects will be in part obvious and in part pointed out more in detail hereinafter.

This invention accordingly consists in the, features of construction, combination of elements and arrangement of parts which will be exemplified in the construction hereafter set forth and the scope of the application which will be indicated in the appended claims.

In the drawings:

FIG. 1 is a partial transverse section view of an embodiment of a slot diffuser of this invention mounted flush within a ceiling panel;

FIGS. 2 through 6 are partial transverse section views of further embodiments of a slot diffuser of the present invention;

FIG. 7 is a partial transverse elevation section view of a modified embodiment of a slot diffuser of this invention;

FIG. 8 is a transverse elevation section view of an assembly of a troifer light and another modified embodiment of a slot diffuser of this invention;

FIG. 9 is an enlargement of a portion of the view of the diffuser and trotfer light assembly of FIG. 8;

FIG. 10 is a reduced perspective view partly broken away of the diffuser and trailer li ht assembly of FIG. 8;

FIG. 11 is a fragmentary section view taken substantially along the line ll1l of FIG. 9;

FIG. 12 is a perspective view partly broken away and partly in section of a further modified embodiment of a slot diffuser of this invention;

FIG. 13 is a fragmentary side elevation view partly broken away and partly in section of the slot diffuser of FIG. 12; and

ddidfi? Patented May 25, 1%65 ice FIG. 14 is a cross section view of the slot diffuser taken substantially along the line 1414 of FIG. 13.

Referring now to the drawings in detail, there is shown in FIG. 1 a slot diffuser having a housing, preferably made of sheet metal, comprising a pair of side walls 1 and 2 which are relatively long and preferably parallel and which are connected at their ends by a pair of relatively short end walls (not shown). The side walls 1 and 2 are provided with inwardly turned lower edges 5 and 6, respectively, which for convenience will be referred to hereinafter as the lip 5 and flange 6. The lip 5 and flange 6 are coplanar and perpendicular to the side walls 1 and 2 and have inner parallel edges that define a slot opening or diffuser outlet 10 having a lateral width designated SW. The slot opening may have a length appropriate to the diffuser capacity desired and preferably, the housing is mounted so that the outer surface of the lip 5 and the flange 6 lie flush with an associated surface, as for ex ample, a ceiling panel 7.

For controlling the air flow passing through the housing passage from its inlet and emitted at its outlet opening 10, there is provided an elongated air deflector plate 12 which in this embodiment is secured to the wall 2 and preferably extends the full length of the housing between the end walls but is of lesser width than the housing to space its elongated edge designated De, hereinafter referred to as the deflector edge, from the side wall 1 so that all the air passing through the housing and emitted from the slot opening 10 must pass therearound. The deflector edge De is located a lateral distance designated Dw (hereinafter called the deflector width) from the side wall 2 and a vertical distance designated Dh (hereinafter called the deflector height) from the slot opening 10. The deflector edge De acts to form with the side wall 1 a restricted passage which displaces the movement of the air within the housing to the right as viewed in the drawings. However, inasmuch as the lip 5 projects from the side wall 1 a distance desginated Lw (hereinafter termed the lip width) beneath this restricted passage, the lip 5 acts to return the air movement to the left as viewed in the drawings, the degree of such leftward movement being determined by the position of an edge designated Le (hereinafter termed the lip edge) located at the terminus of the lip and the width Sw of the slot opening 10. Additionally, the lip edge Le defines with the deflector edge De a second restricted passage having a restriction width designated Rw.

It has been found that when the type of slot diffuser described has a configuration conforming to certain relationships, the air emitted from the slot opening 10 follows a flow pattern that is parallel to the slot opening 10 and which extends outwardly from the slot opening under and in contiguous relation with the flange 6 and ceiling panel 7. Consequently even though the slot diffuser is narrow in width, with the dimension between the side walls 1 and 2 being of the order of two inches, and even though the diffuser side walls 1 and 2 be mounted perpendicular to the opening it and the ceiling panel 7, a highly eflicient air flow pattern that is parallel to the ceiling panel 7 and in which there is substantially laminar flow can be obtained.

To simplify the explanation of the relationships which enable this air flow pattern to be obtained, the lateral distance between the deflector edge De and the lip edge Le, i.e., the component of the restriction width Rw that is parallel to the plane of the outlet opening 10, is termed the see-through Width and designated Rs. It should be noted that though the see-through width Rs could be a negative valve, i.e., by having the deflector plate 12 laterally overlap the lip 5, such overlapping is undesirable as it reduces the efficiency of the air flow within the diffuser housing.

3 The necessary relationships for achieving the highly eflicient laminar flow described are as follows:

(a) Deflector width Dw must be equal to or greater than the see-through width Rs (DwRs).

(b) See-through width Rs must be less than onehalf lip width Lw Slot width Sw must be equal to or greater than the height Dir of the deflector edge De (S w EDh).

(d) Deflector height Dh has a minimum dimension equal to one-third lip width Lw and a maximum dimension equal to three times the lip width LW idhi am) (e) Lip width Lw must be equal to or greater than the restriction width Rs (LwRw).

These relationships remain valid even though different deflector plate configurations are used for forming the deflector edge De. Several examples of deflectors that have been found successful are shown in FIGS. 2 through 6 and, like the deflector plate 12, may be fixed to the wall 2 for defining a deflector edge De which is spaced from the side wall 1 and around which the air flowing through the housing must pass. In these examples, the deflector edge De is formed by a downwardly inclined plate 20 as shown in FIG. 2 by an upwardly inclined plate 22 as shown in FIG. 3 or by a deflector 21 which combines two plates as shown in FIGS. 4 through 6. The inclination of the plate to the plane of the slot opening 16 is designated by the angle a. This angle of inclination a, it has been found, must be 45 or less when the outlet air velocity, as conventionally found in air diffusers of the type to which this invention is directed, is within the range of 400 to 2,000 feet per minute in order to provide the desired flow pattern. The thickness of the lip 5 and the flange 6 does not materially influence the exit flow pattern as long as this thickness is equal to or less than one-quarter of an inch for slot diffusers having a width of approximately two inches or less. A lip or flange having a greater thickness may, however, be used by sharpening or charnfering the edges defining the slot 10, thereby avoiding a downward funneling of the air as it passes through the slot opening lit).

While the foregoing relationships specify maximum dimensional limits, the relationship between the dimensions are varied within the limits specified to obtain the specific characteristics desired for each installation. For example, it has been found that a diffuser with maximum efficiency, i.e., maximum volumetric flow for a given diffuser width and air pressure differential, is usually obtained by having a maximum see-through width Rs. Therefore, by applying the relationships (a) and (b) above, a diffuser having maximum efliciency would be obtained by having the lip width Lw substantially equal to but slightly greater than one-half the distance between the side walls 1 and 2 and have the deflector width Dw and see-through width Rs be substantially equal and therefore, substantially equal to but slightly less than onefourth the distance between the side walls 1 and 2.

A transverse section of another embodiment of a slot diffuser incorporating the relationships of this invention heretofore described is shown in FIG. 7. The diffuser housing generally designated by the numeral 26, has a pair of parallel, relatively long,

side walls

28, 30, preferably made of sheet metal that are connected at their ends by a pair of relatively short end walls (not shown) and which have their lower ends inturned to provide the laterally extending diffuser lip 32 and flange 34 which define and are coplanar with the elongated slot opening 35. Pivotally mounted adjacent the side wall 30 upon an elongated axis 36 is an air controller 38 having an air deflector portion 49 of the type represented generally in FIG. 3 and a stop portion 42 that is adapted to engage the side wall 30 when the deflector portion 40 is positioned for providing an air flow pattern that is parallel to and adjacent the flange 34-. As the deflector portion 40 is pivotally supported, it may be manually adjusted to any position between and including the position shown and a position covering the slot opening 35.

In FIGS. 8 through 11 there is shown a troifer light 56 having a pair of opposed elongated side walls 66 and upon which is assembled an embodiment 52 of an air diffuser of this invention. The air diffuser 52 is bifurcated or yoke-shaped and comprises a plenum chamber housing 53 having a conventional air inlet 49 and air damper 51 and further having a pair of air conduits extending downwardly from the housing adjacent the troifer light side walls 66. The housing 53 is centrally positioned above the trotfer light 50, and the air conduits 55 have inner conduit housing portions 56 that are spaced from the troffer light housing side Walls 66 to provide passages 53 which act as insulating chambers between the air conduits 5:3 and the troffer light housing and thereby prevent an undesirable heating or cooling of the trofier light housing and its inner light reflective surface by the hot or cold air passing through the diffuser conduits. Preferably the air diffuser conduits 55 are constructed separately from the troffer light 56 and are adapted to be fixed thereto by spot welding or otherwise securing the flanges 5d inturned from the outer conduit housing portions 60 upon the top wall 62 of the troffer light housing and by spot welding or otherwise securing the lower ends 64 and 65 (FIG. 9) of the inner and outer

conduit housing portions

56 and 60 respectively, to the lower end of the trolfer light housing side walls 66. The plenum chamber housing 53 is conveniently secured to the conduits 55 as by bolts (not shown) or other well-known means. The conduits 55 are enclosed by the end walls 68 (FIG. 9) inturned from the outer housing portions 60 and are constructed to diverge longitudinally from the plenum chamher so as to distribute the air passing therefrom through the elongated slots 57 in the inturned flanges 54 to a series of elongated slots 74 located in a lateral portion of the housing side walls 66 between the conduit ends 64 and 65.

As best seen in FIG. 9, the lower ends of the trolfer light housing side walls 66 are formed to define a pair of opposed elongated recesses in which there is located the lateral edges 72 of a trolfer cover subassembly that are formed from a piece of sheet metal 76 to define diffuser outlet housings having elongated inner and outer side walls 61 and 63. The sheet metal 76 has therein elongated slots 75 aligned with the slots 74 in the trotfer housing side Walls so as to convey air from the conduits 55 to elongated slots or outlet openings 82 defined by inner and outer elongated edges and which are made by piercing the sheet metal 76 for additionally forming a series of longitudinally spaced deflectors 78 of the type generally shown in FIG. 3 and which are positioned in accordance with the relationships heretofore described. Alternatively, the. desirable lateral air flow from the elongated slots 82 could be obtained without forming the inturned deflectors 78 by appropriately contouring the sheet metal 76 or troffer light housing side wall 66 so that the lateral edge 83 of the

elongated slots

74 or 75 provides a deflector edge that is positioned in accordance with those relationships.

In FIGS. 12 through 14 there is shown a modified t embodiment of an air diffuser of this invention which slots 104, 106 located below the air chambers formed between the

housing side walls

92, 94 and the sheet metal divider 100. The upper end of the housing preferably is adapted to extend into a main air conduit 91, shown in phantom in FIG. 12, and is provided with a peripheral channel 93 with a band of rubber 95 inserted therein to seal the engagement with the main conduit 91 and to reduce vibration that might otherwise pass therebetween. A pair of

slot lips

108, 110 are formed by a central Web 111 in the cover 102 and control the emission of air from the elongated slots 104, 106 in conjunction with a pair of

air deflectors

96, 98 in accordance with the dimensional relationships described. The air deflectors are pivotally mounted within the housing adjacent the

side walls

92, 94 upon a U-shaped wire support 113 that has a pair of legs 112, 114 extending through the side wall 116 longitudinally within the housing and about which the outer ends of the

deflectors

96, 98 are deformed. For maintaining the deflectors in a selected position, there are provided tabs 99 that extend inwardly of the

side walls

92, 94 for friction engagement with the deformed ends of the deflectors, and for facilitating a pivotal adjustment of the deflectors there are provided clips 12d of comparatively short length. The deflectors may either be positioned to completely eliminate air flow through the slots 1414, 1% or may be positioned (as shown by the deflector 98 in FIG. 14) to provide a flow pattern that is parallel to the outlet opening or (as shown by the deflector 96 in FIG. 14) may be pivoted until a deflector stop 107 engages one of the elongated side walls, at which position the deflector forms an angle with the plane of the slot outlet opening that is greater than 45 so as to provide an air flow pattern that is substantially perpendicular to the cover 192.

Within the difluser housing there is shown installed a noise generator 138 that is adapted to provide a minimum background noise level in the room in which the slot diffuser assembly is mounted so as to lessen the eflect of noises originating outside the room and thereby provide a comfortable acoustical environment with the room. This result is largely due to the fact that a human is less annoyed by a steady noise to which he quickly becomes unconsciously accustomed than by sporadic or intermittent noises as for example those caused by passing vehicles, typing or conversation. The noise generator 130 comprises two parallel

sheet metal plates

132 and 134 and a pair of

upright partitions

136 and 138 extending therebetween, and is spaced from the elongated

diffuser side walls

92 and 94 by downwardly extending ribs 140 formed from the side walls and inwardly tapered for supporting the noise generator which is then retained in position by screws 141. The air from the main air conduit 91 passes around the edges of the

plates

132, 134 adjacent the elongated diffuser side walls thereby creating a vibration which is amplified at certain frequencies by the air column in the acoustical chambers 144, such frequencies being dependent upon the lateral position of the upright partitions 136 and 133.

It can be seen that the diffuser of this invention has unusual versatility and can be used in conjunction with numerous apparatus such as with a noise generator or with a trofler light, and can be made in a length or in combination of lengths according to the dictates of each installation. Additionally, the difluser of this invention provides a simplified means for emitting air with maximum efiiciency and minimum turbulence in a pattern that is parallel to the diffuser opening, and where desired can be constructed with an adjustment for additionally directing the air outwardly along a path that is substantially perpendicular to the difluser outlet opening.

As will be apparent to persons skilled in the art, various modifications and adaptations of the structure above described will become readily apparent without departure from the spirit and scope of the invention, the scope of which is defined in the appended claims.

I claim:

1. An air diffuser comprising, a housing having one pair of relatively long generally upstanding closely spaced side walls connected by a second pair of relatively short end walls and inlet and outlet openings and forming an elongated narrow air outlet passageway with substantially downward air flow, an elongated lip extending laterally inwardly in the plane of the outlet opening from a first of said one pair of side walls forming an elongated lip edge defining one lateral edge of the outlet opening, and an air deflector member pivotally mounted within the housing about an axis parallel to the lip edge and adjacent a second of said one pair of side walls, said deflector member being movable between a first position overlapping the outlet opening for preventing air flow therethrough and a second position, said deflector member forming a deflector edge lying substantially parallel to the lip edge, said deflector member when in its second position having its deflector edge a distance from the lip edge which is no greater than the distance between the lip edge and the first side wall, and said deflector member when in its second position further having its deflector edge a distance from the outlet opening which is no less than one-third of and no greater than three times the distance between the lip edge and the first side wall, said lip edge and said deflector edge being related with the deflector in said second position to discharge the air passing downwardly through the elongated narrow air outlet passageway through the outlet opening into a path parallel to the outlet opening.

2. An air diffuser comprising, a housing having a pair of relatively long generally upstanding side walls connected by a pair of relatively short end walls and an inlet opening, means intermediate of the housing side walls forming a pair of parallel elongated edges defining in part a pair of parallel elongated outlet openings laterally spaced between said side walls, a partition within the housing intermediate of the pair of side walls forming therewith a pair of elongated narrow air outlet passageways with substantially downward air flow adjacent the outlet openings, said outlet openings being parallel to and laterally spaced on opposite sides of said partition, and air deflector members pivotally mounted within the housing adjacent said pair of side walls defining deflector edges spaced from the partition and movable for varying the air flow through the outlet openings, said deflector members being movable to a first position whereat the distance of the deflector edges from the outlet openings is no greater than the lateral width of the outlet openings, the deflector edges are spaced from the outlet openings intermediate the lateral edges thereof, and whereat the distance between the deflector edges and the pair of side walls is at least equal to the lateral distance between the deflector edges and the elongated edges, said elongated edges and deflector edges being related with the deflectors in said first position to discharge the air passing downwardly through the elongated narrow air outlet passageways through the outlet openings in opposite directions into paths parallel to the outlet openings.

3. The air diffuser of claim 2 wherein the air deflector members are movable between a second position covering the elongated outlet openings and said first position, each or" said deflector members in their first position forming an angle with the plane of the adjacent outlet opening that is less than 45.

4. The air difluser of claim 2 in combination with a noise generator comprising a pair of vertically spaced plates extending substantially normal to the side walls, said plates extending between but spaced from said pair of relatively long side walls for defining air passages therewith, and upstanding partition means intermediate the side walls and extending between the pair of vertically spaced plates for defining a pair of acoustical chambers whereby air passing through the diffuser housing around the pair of spaced plates will create sound waves that are amplified by the acoustical chambers.

5. For use in combination with a trofler light having an elongated housing with a pair of opposed elongated side walls, an air difluser comprising, a plenum chamber housing having an air inlet and adapted for being positioned above the trofler light housing, a pair of air conduits having their upper ends connected to the plenum chamber housing and adapted to extend downwardly adjacent the opposing elongated side walls thereof, housing means including a pair of generally upstanding closely spaced elongated side walls and forming first and second spaced elongated edges defining elongated outlet openings and upwardly facing inlet openings communicating with the lower ends of the air conduits, and elongated air deflector members within the housing forming deflector edges spaced inwardly of the elongated outlet openings between the first and second elongated edges, the distance of the deflector edges from the outlet openings being no greater than the distance between the first and second elongated edges, the first and second spaced elongated edges and the deflector edges being related to discharge the air passing downwardly through the air conduits through the outlet openings into paths parallel to the outlet openings.

6. For use in combination with a trofler light assembly having an elongated housing with a pair of opposed elongated side walls, an air diffuser comprising, a plenum chamber housing having an air inlet and adapted for being positioned above the troffer light housing, a pair of air conduits having their upper ends connected to the plenum chamber housing and extending downwardly therefrom for being positioned adjacent to but at least partially spaced from the opposing elongated side walls of the trofier light housing, means forming elongated diffuser outlet housings having inner and outer elongated generally upstanding closely spaced side walls and an upwardly facing inlet opening communicating with the lower ends of the air conduits, said conduits diverging longitudinally from the plenum chamber housing to the elongated outlet housings, means forming inner and outer elongated edges for defining elongated outlet openings for the housings below the side walls thereof, and elongated air deflector members extending from adjacent the outer elongated side walls and forming deflector edges that are parallel to and spaced inwardly of the outlet openings, the lateral distance between the deflector edges and the inner edges being less than one-half the distance between the inner edges and the inner side walls, the distance between the deflector edges and the outlet openings being no greater than the distance between the inner and outer edges, and the distance between the inner edge and the inner side wall being at least equal to the distance between the inner edge and the deflector edge, said inner and outer elongated edges andsaid deflector edges being related to discharge the air passing downwardly through the air conduits through the outlet openings into path parallel to the outlet openings.

7. An air difluser for use in combination with a ceiling comprising, an elongated housing having an air inlet opening, an air outlet opening, and a pair of elongated upstanding side walls in laterally spaced generally parallel relationship intermediate the air inlet opening and air outlet opening forming a downwardly extending narrow air outlet passageway having a height greater than its lateral width for funneling the air flow downwardly from the air inlet opening to the air outlet opening; said elongated housing being adapted to be mounted within an opening in the ceiling with the air inlet opening above the ceiling, with the air outlet opening substantially in the plane of the ceiling and with the upstanding side walls extending upwardly from the ceiling; an elongated lip extending laterally inwardly from one of said pair of side walls at the lower end thereof forming an elongated lip edge defining one lateral edge of the air outlet opening, a flange extending laterally inwardly from the other side wall at the lower end'thereof forming an elongated flange edge defining the opposite lateral edge of the air outlet opening, said flange and lip being substantially coplanar, and air deflector means mounted in said air outlet passageway to extend from said other side wall and forming a deflector edge having an operative position spaced from said one side wall and inwardly of the outlet opening between the flange and lipedges; and whereat the deflector edge is substantially parallel to the lip edge, whereat the distance between the lip edge and the one side wall is at least equal to the distance between the lip edge and the deflector edge, and whereas the deflector edge, lip edge and flange edge are related to discharge the air funneled downwardly through the narrow air outlet passageway through the outlet opening into a path parallel to the outlet opening and along the ceiling.

8. An air diffuser for use in combination with a ceiling comprising, an elongated housing having an air inlet opening, an air outlet opening and a pair of elongated upstanding side walls in laterally spaced generally parallel relationship intermediate the air inlet opening and air outlet opening forming a downwardly extending narrow airoutlet passageway having a height greater than its lateral width for funneling the air flow downwardly from the air inlet opening to the air outlet opening; said elongated housing being adapted to be mounted within an opening in the ceiling with the air inlet opening above the ceiling, with the air outlet opening substantially in the plane of the ceiling and with the upstanding side walls extending upwardly from the ceiling; an elongated lip extending laterally inwardly from one of said pair of side walls at the lower end thereof forming an elongated lip edge defining one lateral edge of the air outlet opening, a second edge defining the opposite lateral edge of the outlet opening, and an air deflector pivotally mounted within the housing forming an air deflector edge; said air deflector being pivotal to an operative position whereat the deflector edge is spaced from said one side wall inwardly of the outlet opening, whereat the deflector edge, the second edge, and the lip edge are substantially parallel, whereat the lateral dlstance between the deflector edge and the lip edge is less than one-half the distance between the lip edge and said one side wall, whereat the distance of the deflector edge from the outlet opening is no greater than the distance between the lip and second edges, whereat the distance of the deflector edge from the outlet opening is no less than one-third of and no greater than three times the distance between the lip edge and said one side wall, whereat the distance between the lip edge and the one side wall is at least equal to the distance between the lip edge and the deflector edge, whereat the distance between the deflector edge and the other of said pair of side walls is at least equal to the lateral distance between the defiector edge and the lip edge, and whereat the deflector edge, the lip edge and the second edge are related to d1scharge the air funneled downwardly through the narrow air outlet passageway through the outlet opening into a path parallel to the outlet opening and along the ceiling.

9. An air difluser for use in combination with a ceiling comprising, an elongated housing having an air inlet opening, an air outlet opening and a pair of elongated upstandlng side walls in laterally spaced generally parallel relationship intermediate the air inlet opening and air outlet opening forming a downwardly extending narrow air outlet passageway having a height greater than its lateral width for tunneling the air flow downwardly from the air inlet opening to the air outlet opening; said elongated housing being adapted to be mounted within an opening in the ceiling with the air inlet opening above the ceiling, with the air outlet opening substantially in the plane of the ceiling and with the upstanding side walls extending upwardly from the ceiling; an elongated lip extending laterally inwardly from one of said pair of side walls at the lower end thereof forming an elongated lip edge defining one lateral edge of the air outlet opening, a flange extending laterally inwardly from the other of said pair of side walls at the lower end thereof forming an elongated flange edge defining the opposite lateral edge of the outlet opening, said flange and lip being substantially coplanar, and an air deflector pivotally mounted Within the passageway forming an air deflector edge; said air deflector being pivoted to an operative position whereat its external surfaces extend from adjacent the second side wall, whereat its air deflector edge is spaced inwardly of the outlet opening between the flange and lip edges, whereat the deflector edge, lip edge and flange edge are parallel, whereat the external surfaces of the air deflector form with the plane of the outlet opening an angle of no greater than 45, whereat the lateral distance between the deflector edge and the lip edge is less than one-half the distance between the lip edge and said one of the pair of side walls, and whereat the deflector edge, lip edge and flange edge are related to discharge the air funneled downwardly through the narrow air outlet passageway through the outlet opening into a path parallel .to the outlet opening and along the ceiling.

10. An air difluser for use in combination with a ceiling comprising, an elongated housing having an air inlet opening, an air outlet opening and a pair of elongated upstanding side walls in laterally spaced generally parallel relationship intermediate the air inlet opening and air outlet opening forming a downwardly extending narrow air outlet passageway having a height greater than its lateral width for tunneling the air flow downwardly from the air inlet opening to the air outlet opening; said elongated housing being adapted to be mounted within an opening in the ceiling with the air inlet opening above the ceiling, with the air outlet opening substantially in the plane of the ceiling and with the upstanding side walls extending upwardly from the ceiling; each of said pair of side walls having laterally inturned lower ends for defining the outlet opening, a first of the inturned ends forming a first edge defining one edge of the outlet opening, a second of said inturned ends having a first portion substantially coplanar with the first inturned end and forming a second edge defining the opposite edge of the outlet opening, said second inturned end having a second deflector portion extending within the housing from said first portion at an angle of no more than 45 with the plane of the outlet opening, said deflector portion forming a deflector edge spaced inwardly of the outlet opening between said first and second edges, said first, second and deflector edges all being parallel; the lateral distance between said first and second edges being no less than the distance between the deflector edge and the plane of the outlet opening, and said first edge, second edge and deflector edge being related to discharge the air funneled downwardly through the narrow air outlet passageway through the outlet opening into a path parallel to the outlet opening and along the ceiling.

11. An air diffuser for use in combination with a ceiling comprising, an elongated housing having an air inlet opening, an air outlet opening, a pair of laterally spaced elongated air outlet openings, a pair of elongated upstanding side walls in laterally spaced generally parallel relationship intermediate the air inlet opening and the air outlet openings, means intermediate of the housing side walls at the lower ends thereof forming a pair of generally parallel elongated edges defining in part the pair of elongated air outlet openings, an elongated upstanding partition within the housing intermediate the outlet openings and the pair of side walls and forming with the side walls a pair of laterally spaced narrow air outlet passageways each having a height greater than its lateral width for tunneling the air flow downwardly from the air inlet opening to the air outlet openings, and a pair of air deflectors extending inwardly from adjacent said pair of side walls respectively forming deflector edges having operative positions spaced from said partition for causing air flow through the narrow air outlet passageways to pass therebetween, and whereat the lateral distance between the deflector edges and said elongated edges is less than one-half the distance between the elongated edges and the partition respectively, whereat the distance between the elongated edges and the partition is at least equal to the distance between the elongated edges and the deflector edges respectively, and whereat the elongated edges and deflector edges are related to discharge the air funneled downwardly through the elongated narrow air outlet passageways through the parallel outlet openings in opposite lateral directions into paths parallel to the outlet openings and along the ceiling.

References Cited by the Examiner UNITED STATES PATENTS 2,656,156 10/53 Wilcox 98-40 2,962,582 11/60 Croft 98-40 2,991,708 7/61 Falk 98-40 3,072,03 8 1 63 Phillips 9840 3,126,811 3/64 Kennedy 9840 FOREIGN PATENTS 882,307 5/43 France.

ROBERT A. OLEARY, Primary Examiner.

CHARLES E. OCONNELL, Examiner,