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Publication numberUS3608468 A
Publication typeGrant
Publication dateSep 28, 1971
Filing dateAug 15, 1969
Priority dateAug 15, 1969
Publication numberUS 3608468 A, US 3608468A, US-A-3608468, US3608468 A, US3608468A
InventorsMcclurkin Cloise M
Original AssigneeMcclurkin Cloise M
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Adjustable air-curtain system
US 3608468 A
Abstract  available in
Previous page
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Claims  available in
Description  (OCR text may contain errors)

United States Patent Primary ExaminerMeyer Perlin Assistant ExaminerRonald C. Capossela Attorneys-Clarence A. OBrien and Harvey B. Jacobson ABSTRACT: An air-curtain installation incorporating a pair of independent duct systems positionable in slightly spaced adjacent parallel orientation to each other and oriented so as to define two separate diverging air curtains. Each system includes its own power-driven blower and is supplied with air drawn solely from the side to which the corresponding curtain is directed. Each duct system also includes adjustable vanes or baffle plates utilized particularly along the vertical sides of the ducts so as to selectively vary the amount of air discharged thereby at the upper and lower end of the sides for an accommodation of varying temperature conditions. The entire system is preferably prefabricated into three basic units, a pair of opposed sidewalls incorporating the side duct portions therein, and an overhead blower housing incorporating the horizontal duct portions which interlock with the side duct portions upon an assembly of the three units.

x x i I 4 r e: .3 i

is i 3 I 5 /I0 1 1 .20 l l I /54 54 i 44 24 i r i ,1 i {24 20 i I F I 1 i! i i at Ell. Li f ADJUSTABLE AIR-CURTAIN SYSTEM The invention herein generally relates to the provision of an air barrier or curtain between two areas of differing temperature wherein maintenance of the temperature difference is desired while at the same time allowing for free access between the areas.

While air curtains of various types are known it is the intention of the instant invention to provide a novel air-curtain system including a pair of independently supplied air ducts orientated so as to define a pair of back to back diverging air curtains with the continuous discharge vent associated with each duct being adjustable for the accommodation of varying temperature conditions.

Also of particular significance in regard to the present invention is the construction of the air-curtain system in three basic readily assemblable units for simplified erection adjacent a doorway or opening between the two areas of differing temperatures.

Basically, the invention consists of two vertical side wall units, each incorporating a pair of vertical parallel laterally spaced duct sections, and an overhead blower housing, also incorporating a pair of duct sections, these latter duct sections being horizontally orientated and adapted to interconnect and communicate with the upper ends of the opposed pairs of wall-mounted duct sections. The communicated duct sections form a pair of independent ducts, each including a continuous air-discharging vent within which adjustable vanes or baffle plates are mounted. Each duct is independently supplied by a separate blower which is so orientated as to draw air from the side of the air barrier toward which the particular duct is directed.

These together with other objects and advantages which will become subsequently apparent reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming a part thereof, wherein like numerals refer to like parts throughout, and in which:

FIG. 1 is a perspective view of an installation in accordance with the instant invention;

FIG. 2 is an enlarged cross-sectional view taken substantially on a plane passing along line 2-2 in FIG. 1;

FIG. 3 is a partial cross-sectional view taken substantially on a plane passing along line 3-3 in FIG. 2;

FIG. 4 is a cross-sectional detail taken along substantially on a plane passing along line 44 in FIG. 2;

FIG. 5 is a cross-sectional view taken substantially on a plane passing along line 5-5 in FIG. 2; and

FIG. 6 is an elevational view of one of the adjustable vanes or baffle plates.

Referring now more specifically to the drawings, the illustrated embodiment of the air-curtain system of the instant invention is constructed in three prefabricated units, a pair of opposed sidewalls l0 and an overhead or top housing 12 assemblable adjacent and about a door or passageway 14 provided between two areas of different temperatures between which the temperature variation is to be maintained.

Each of the sidewalls 10, constructed of an appropriate structural material, includes a pair of parallel full-height duct portions or sections 16. These duct portions 16 are laterally spaced from each other a slight distance and will preferably have an appropriate spacer or spacing material 18 located therebetween. Noting FIG. 4 in particular, each of the sidewall vertical duct portions 16 is generally rectangular in cross section, having a forward wall 20 generally coextensive with the inner face 22 of the corresponding wall 20 and angled slightly inward relative thereto. The front walls or panels 20 of the two duct portions 16 within each sidewall 10 are angled in opposite directions so as to in effect diverge from each other whereby a pair of diverging air curtains will be formed as will be explained subsequently Each of the duct portion front panels 20 terminates sufficiently short of the far side panel 24 of the corresponding duct portion so as to define a relatively wide air-discharging vent 26 along the full height of the duct portion. I

The overhead unit or housing 12 also includes a pair of laterally spaced parallel elongated duct portions 28. These duct portions 28, corresponding in size and shape to the duct portions 16, extend horizontally along the bottom portion of the housing 12 and open downwardly therethrough, being provided with slightly inclined front panels 30 which terminate short of the corresponding duct portion side panels 32 whereby air-discharging vents 34 are formed. The extreme ends of the horizontal duct portions 28 are, noting FIG. 3 in particular, downturned and provided with means, for example the illustrated reduced end portions 36, for interlocking with the upper ends of the sidewall duct portions 16 whereby a continuous hollow duct is formed between the horizontal overhead duct portion 28 and the vertical sidewall duct portions 16.

Mounted in the housing 12 laterally outward of each duct portion 28, that is toward the opposite side thereof relative to the other duct portion 28, is an enlarged blower 36 which, through a separate blower housing 38, is communicated centrally directly with the adjacent duct section 28. Each blower 36 is powered by an appropriate motor 40, also mounted within the housing 12, which motors will be externally controlled through an appropriate switch or switches, the motors preferably being synchronized for simultaneous operation. As will be appreciated, each elongated duct, consisting of the two aligned side duct portions 16 and the interconnecting horizontal duct portion 28, is supplied with pressurized air by the associated blower 36. The blowers 36 in turn each receives air from its corresponding side of the air curtain which is to be defined through a pair of air vents 42 provided adjacent-each of the blowers 36. In this manner, the air that is directed through each elongated duct is taken from that side of the air curtain toward which the corresponding duct discharges. Thus, there is no intermingling of the air between the two areas of different temperature, and in fact, due to the diverging nature of the two formed air curtains, there is actually formed a dead airspace therebetween which significantly contributes to the prevention of movement of air from one area to another. The orientation of the vents or openings 42 in the bottom of the housing 12 adjacent the associated blowers 36 ensures a movement of the air directly to the corresponding blowers whereby no intermingling of the air between the adjacent temperature areas occurs within the housing. However, if so desired, an actual partition can internally divide the housing 12 between the two horizontal duct portions 28.

Referring now again to the sidewall duct portions 16, a series of vertically spaced substantially rigid connecting straps 44 are provided across each vent opening 26. Each of these straps 44 is bolted, through a laterally directed flange 46 thereon, to the duct portion side panel 24 and projects therefrom into underlying relation with the adjoining front panel 20. Each strap 44, at a point where it underlies the corresponding front panel 20, includes an internally threaded hole 48 therein which aligns with an unthreaded hole 50 in the overlying portion of the front panel 20 for the reception of a threaded bolt 52 therethrough. A full-height vane or baffle plate 54 extends vertically along each duct portion 16 and is slidably mounted between the vertically spaced straps 44 and the duct portion front panel 20 for a selective lateral sliding thereof so as to vary the effective width of the vent opening 26. Each vane includes a laterally directed full-length flange 56 which projects laterally outward through the corresponding vent opening 26 and provides a convenient means for manipulating the vane. In addition, each vane 54 includes a transversely elongated slot 58 therein aligned with each pair of bolt-receiving openings 48 and 50 for the reception of the corresponding bolt 52 therethrough. In this manner, upon a loosening of the bolts 52, the corresponding vane 54 can be laterally slid or adjusted, within the limits of the slots 58, to the desired position, after which a retightening of the bolts 52 will effect a slight flexing of the straps 44 towards the front panel 20 and a corresponding clamping of the vane 54 in the adjusted position. Normally three straps 44 are associated with I each duct portion 16, one toward each end thereof and one centrally located whereby the corresponding vane or baffle plate 54 can in effect be pivoted about the central strap bolt so as to selectively increase the effective width of the vent at one end of the duct portion 16 while decreasing the effective width at the opposite end of the duct portion 16. The ability to so adjust the vent opening is particularly significant where the temperatures in the two temperature areas will periodically reverse, that is the colder area will become the warmer area. This will occur, as one example, at exterior entranceways whereby during cool weather conditions, as in the winter, the interior of the establishment will be heated relative to the colder exterior, while during warmer weather conditions, as in the summer, the interior area will be cooled or air conditioned relative to the warmer outside air. On the cooler or cold side of the curtain system, the vanes 54 of the corresponding duct portions 16 will be orientated so as to provide a wide vent opening at the bottom thereof and a narrow vent opening at the top thereof. ln this manner, there will be a larger volume of air discharging at the lower portion on the cold side, thereby tending to keep the heavier cold air from moving or rolling in through the lower portion of the curtain system. By the same token, on the warmer side of the curtain system, the corresponding vanes 54 are adjusted so as to provide a wider vent opening at the top of corresponding side duct portion 16 and a narrower vent opening at the lower portion of the duct portion 16, thereby forming a larger air discharge at the upper portion thereof so as to prevent an outward movement of the relatively lighter warm air. In this manner, the effectiveness of the dual-curtain system has been greatly enhanced, and the adjustability of the effective widths of the discharge vents so as to, as one example, accommodate seasonal weather changes, greatly enhances the adaptability of the disclosed system for use not only between two internal areas, but also at outer passageways wherein free access is desired, such as in commercial establishments of various types.

The overhead duct portions 28 are similarly provided with transverse mounting straps 59 and adjustable vanes or baffle plates 60 which are mounted and adjustable in the same manner as described supra in conjunction with the straps 44 and vanes 54. However, rather than utilizing the vanes 60 for effecting a variation between the openings in the corresponding vents 34 between the opposite ends of the duct portions 28, the vanes 60 will normally be moved parallel across the corresponding vent openings so as to maintain the vent opening constant along the full length of each duct portion 28 whereby a constant discharge will be provided overhead across the opening. Each of these overhead vanes 60 will be normally adjusted so as to correspond with the upper portions of the associated vertical side vanes 54, that is, a wide vent opening will be provided in the overhead duct portion 28 toward the warm area, and a narrow vent opening will be provided in the overhead duct portion 28 toward the cold area.

From the foregoing, it will be appreciated that a highly unique adjustable air-curtain system has been described. The formation of the system in basically three prefabricated units greatly facilitates the installation thereof in that all that is required is the erection of the two sidewalls l and the mounting of the overhead housing 12 thereover. In those instances wherein the system is to be assemblied adjacent an exterior access into a building, the sidewalls will be suitably stabilized and sealed to the building wall in any appropriate manner, utilizing conventional construction methods. In interior installations, between areas or rooms of different temperatures the system can be installed in either area and secured to the interior partition for a stabilization of the three units. Incidentally, while the system of the instant invention, in the preferred embodiment, contemplates the utilization of the aforedescribed three prefabricated units, it will be appreciated that the two ducts, with their associated blowers, can actually be installed separately to the opposite sides of a door or passageway, in which instance the sidewalls l0 and overhead housing 12 will be eliminated and appropriate ductand blower-mounting means utilized to position the components directly on the area dividing partition. However, even in such an installation, the duct vents will be so orientated, angled at approximately a 15 angle, as to present diverging air curtains which, in conjunction with the adjustable vanes so as to vary the effective opening of the vents, will produce the highly effective barrier sought by the instant invention. With either installation, it will be appreciated that the air-curtain system is provided without requiring any modification of the actual building partition adjacent which it is to be mounted, the system, in the preferred embodiment, being in fact a separate self contained assembly which, if so desired, need not be affixed to the area-dividing partition, but may be merely positioned closely thereagainst, providing in effect a portable system.

The foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly all suitable modifications and equivalents may be resorted to, falling within the scope of the invention.

What is claimed as new is as follows:

1. An air curtain system comprising a pair of parallel air ducts, a pair of blowers, each blower communicated with one of said air ducts, each duct including communicating portions arranged so as to define a passage transversely therebetween, each duct portion having an air-discharge vent defined longitudinally therein, the vents in the duct portions of each duct discharging air generally toward each other across said passage and at an angle to the discharge of the vents in the portions of the other ducts so as to define diverging air curtains, and means for adjusting the effective widths of the duct portion vents, the means for adjusting the widths of the vents comprising an elongated platelike vane paralleling each vent and mounted for selective sliding transversely thereacross and pivotal adjustment relative thereto whereby a variation in the effective width of the corresponding vent can be provided along the length thereof with each end portion of the vent being made selectively larger or smaller than the other as desired.

2. The system of claim 1 wherein said duct portions are laterally spaced and vertically orientated to define side portions.

3. The system of claim 2 wherein the duct portions of each duct are interconnected and communicated by a transverse overhead portion.

4. The system of claim 3 wherein three prefabricated units are utilized, said units comprising a pair of laterally spaced side units and an overhead unit, each side unit mounting one vertical duct side portion from each duct in adjacent parallel relation to each other, said overhead unit mounting the overhead duct portions of the twoducts in horizontal adjacent parallel orientation relative to each other, and means for interconnecting said overhead unit with the upper ends of the two side units and communicating each overhead duct portion with the corresponding side duct portions so as to define said pair of parallel air ducts, said side and overhead units having a common coplanar edge for close engagement against a wall surface.

5. An air-curtain system including three assemblable prefabricated units, said units comprising a pair of laterally spaced vertically orientated side units, and a horizontally positioned overhead unit, each of said side units comprising a walllike structure mounting two vertically orientated parallel duct sections, each of said duct sections including a longitudinally extending vent therein opening toward the other side unit, said overhead section comprising an enlarged housing mounting a pair of longitudinally extending parallel duct sections, each of said overhead unit duct sections including a longitudinally extending vent therein opening downwardly, and a pair of blowers mounted within said overhead unit, one blower communicating with each overhead unit duct section and effecting a forced movement of air in opposite directions therealong,

said overhead unit being positionable upon the upper ends of the side units, said overhead unit duct sections each being directly communicated with one side unit duct portion in each side unit for a movement of air thereinto and a subsequent discharge of air through the associated vents.

6. The construction of claim 5 wherein the two formed ducts have the combined vents therein orientated so as to discharge blower-impelled air in a pair of diverging air curtains, each of said duct portions mounting an adjustable vane selectively movable so as to vary the effective width of the corresponding vent.

7. An air-curtain system including an air duct arrangeable peripherally about an opening communicating two areas of different temperatures, said duct including a pair of opposed duct sections, an air blower communicated with said duct for the introduction of pressurized air thereinto, said duct including inwardly directed vent means alon the major portion of the length thereof, including the opposed duct sections, for the discharge of air therethrough, said vent means being directed so as to discharge generally across the opening, and adjustable vane means mounted on said duct adjacent said vent means, said vane means being selectively adjustable as to vary the effective width of the vent means both equally along the length thereof and variably along the length thereof.

8. The construction of claim 7 wherein said vent means comprises an elongated opening defined in said duct, said width-regulating vent means comprising a flat platelike member mounted on said duct longitudinally along said opening and selectively laterally slidable across said opening.

Patent Citations
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US3293878 *Dec 23, 1965Dec 27, 1966Barroero Louis FRefrigerated display case having selfcontained refrigeration unit
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3717160 *Aug 20, 1971Feb 20, 1973Tobias PAutomatic sheet material transport machine
US3797373 *Jul 19, 1972Mar 19, 1974Npi CorpAir curtain
US4320695 *May 9, 1980Mar 23, 1982Ab Svenska FlaktfabrikenAir diffuser
US4865011 *Jun 16, 1987Sep 12, 1989Vermont Casings, Inc.Solid fuel burning space heating appliances
US6874331 *May 16, 2003Apr 5, 2005Manitowoc Foodservice Companies, Inc.Device and method for creating a horizontal air curtain for a cooler
US6960129 *Jan 9, 2004Nov 1, 2005Hcr IncorporatedConditioned vestibule for a cold storage doorway
US20040003617 *May 16, 2003Jan 8, 2004Chandler Michael S.Device and method for creating a horizontal air curtain for a cooler
US20040192187 *Jan 9, 2004Sep 30, 2004Paul AshleyConditioned vestibule for a cold storage doorway
US20070298703 *Jun 23, 2006Dec 27, 2007Chih-Feng ChenInsect proof wind generating device
DE102012104818B3 *Jun 4, 2012Oct 10, 2013Thermofin GmbhThermal lock for cold storage house, has cooling system module for generating warm-air curtain for internal door, and cold-air curtain for external door, where air curtains are generated from air intake of thermal lock
EP0058782A1 *Feb 24, 1981Sep 1, 1982Stichting Ontwikkeling KoeltechniekCold-storage building
EP0900990A3 *Aug 4, 1998Jul 19, 2000Ingenieurgemeinschaft WSP Prof. Dr.-Ing. C.Kramer Prof. H.J. Gerhardt, M.Sc.Air curtain device pass
WO1982002934A1 *Feb 24, 1981Sep 2, 1982Vahl LaszloCold-storage building
U.S. Classification454/192
International ClassificationF24F9/00
Cooperative ClassificationF24F9/00
European ClassificationF24F9/00