US3577654A - Forced air diffuser - Google Patents

Abstract

In abstract, a preferred embodiment of this invention is a portable air diffuser including an air duct network fitted at the intake extremity with a blower and having a series of baffles attached to the outflow extremity with intermediate dampening control means.

Description

United States Patent lnventor James A. Marley 801 W. Hudson St., Fayetteville, N.C. 28306 Appl. No. 849,757

Filed Aug. 13, 1969 Patented E May 4, 1971 FORCED AIR DIFFUSER I 3 Claims, 5 Drawing Figs.

US. Cl 34/231, '98/40B Int. Cl F24f 13/06, F26b 19/00 Field of Search 126/595;

References Cited UNITED STATES PATENTS 342,591 5/1886 Farrar et al. 34/218X 845,047 2/ 1907 Beernink 34/232X 2,114,942 4/1938 Sugg 34/231 2,207,201 7/1940 Kurth 98/40BX 3,126,198 3/1964 Wise 263/19A Primary Examiner-Charles .l. Myhre Att0mey.l0hn G. Mills, Jr.

ABSTRACT: In abstract, a preferred embodiment of this invention is a portable air diffuser including an air duct network fitted at the intake extremity with a blower and having a series of baffles attached to the outflow extremity with intermediate dampening control means.

Pmmeum 4m; I 3577.654

Q SHEET 1 0F 2 INVENTOR. JAMES A. MARLEY BY AM 07 AT TORNEIY PATENTED m 4197:

SHEET 2 OF 2 INVENTOR.

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' ATT0R/VE7 1 roncan AIR n rrus'sn This invention relates to drying means and more particular to devices for evenly distributing heated air within tobaccotype curing barns.

In the past, various means have been devised to distribute heated air throughout a tobacco barn during the curing process. The classical means has been by natural conviction whereby heat sources situated beneath the mass of tobacco heat the ambient air causing the same to rise through the hanging thus transferring heat as it so moves. As the heated air rises, it naturally avoids areas of greater resistance where the leaves are hung in thicker quantities, thus resulting in what is typically referred to as cold spots. In addition, the heated air tends to rise in vertical columns above the heat sources and fails to adequately reach fringe areas of the barn .such as cornets and along the walls. The result is a nonuniform cure which degrades the quality of the leaf significantly.

Forced convection by blowing or inducing air flow has also been used in drying-enclosures to overcome the undesirable qualities of drying by natural convection but these devices have been found unsatisfactory in many cases due to .lack of controlover the flow rate. Also many of these prior known systems have been undesirable because of the inconvenience and expense of installation which often become a permanent fixture to the drying enclosure. V g

The present invention has been developed after much research and study into the above-mentioned problems and is designed to diffuse fresh air into the lower portions of a drying enclosure in such a manner as to distribute and force the heated airuniformly upward throughout the material being dried. This has been accomplished by providing a generally L- shaped air duct network having a blower fitted to the intake extremity and a series of horizontally disposed baffles attached to'the outflow extremity with an intermediate'dampening device for control of air flow rate.

It is an object, therefore, of the present invention to'provide a portable air difi'user to supplement conventional drying means by evenly distributing and forcing hot r uniformly throughout the product to' be dried.

Another object of the presentinvention is to provide an air distribution system having dampening means whereby the rate of air flow may'r'eadily be controlled.

A further object of the present invention is to provide an air distribution system having blower means to force fresh air into a drying enclosure for the purpose of cooling.

Another object of thepresent invention is to provide a series of stacked, progressively smaller baffles having progressively smaller central openings therein disposed above the upturned outlet end of a dryer enclosure fresh air inlet system.

An additional object of the present invention is to provide a fresh air diffuser within a drying enclosure to horizontally disperse such air in overlapping layers thus causing even convection heating without cold spots.

Another object of the present invention is to provide a portable, easily assemblable and disassemblable fresh air diffuser system for tobacco-type curing enclosures.

Other objects and advantages of the present invention will become apparent and obvious from a study of the following description and the accompanying drawings which are merely illustrative of the present invention.

In the drawings:

FIG. 1 is a perspective of a preferred embodiment of the forced air diffuser of the present invention;

FIG. 2 is a perspective of such diffuser showing its use within a typical tobacco type curing barn;

FIG. 3 is top plan view of theindividual baffles used in a typposed of horizontally disposed intake ducts 11 and 12, elbow 13 and vertically disposed discharge duct 14. These duct indicated generally at 10 is substantially circular in cross section and generally L-shaped in elevation. This network is commeans are detachably connected to form a continuous conduit extending from intake and 15 to exhaust e'nd l6.

Releasably attached to end '16 of network 10 is blower unit 1.7 within which a standard sq'uirrel cage fan (not shown) is operatively attached to a drive motor (not shown). A protective screen guard 18 is provided over the intake opening 19 of unit 17.

lnteriorly mounted within horizontal duct 12 is a damper means 20 which is preferably of the butterfly valve type. A handle means 21 is fixedly secured to the exteriorly projecting end 22 of valve-supporting shaft 23. There is provided, to support the elbow 13'and the upright or vertically disposed duct 14, a leg connecting collar 24 which may be either releasably or fixedly secured to and disposed about the intermediate portion of said last-mentioned duct. A plurality of leg means 25 depend from and releasably attach to the collar 24 by way of leg-receiving sleeves 26 intermittently spaced around the outer edge of such collar. These legs, which usually would be threein number, are of such a length that their club-shaped foot portion 27 will engage the floor or ground slightly below the lower extremity of elbow 13 to hold the same and its related ducts 11 and 12 in spaced relation therefrom.

A series of spaced, stacked, progressively smaller air diffusing-baffle means 30 are disposed above and attached to the upper, exhaust end 16 of duct 14. As the baffles become progressively-smaller in the stack, the respectivecentrally disposed openings therein become progressively smaller particularly, as seen in FIG. 3. v

To support and hold the baffles in relative fixed, stacked relationship there are provided a plurality of spacer means 28.

In actual use of the air-diffusing device of the present invention, an opening 28 in the side of the drying enclosure or barn 29 is provided through which duct 11 is disposed. Ducts 12 and 14, with intermediate elbow 13, are assembled. Support legs 25 are attachable to collar 24. Also the fan unit 17 with its interiorly mounted blower (not shown), is connectively and operatively attached to the inlet end 15 of duct 11 exterior of "and projecting from barn 29.

Since the baffles 30 are fixedly attached in spaced relation over the upper, exhaust end 16 of vertically disposed duct 14, the diffuser of the present invention, when assembled as hereinabove described, is ready for operation.

When it is desired to dry or cure tobacco or other products spacingly disposed in the upper portion of the enclosure or barn 29, one or more heater means 31 is disposed in the interior of such enclosure below the level of the stacked baffles. As the heater or heaters are operated, the fan (not shown) within blower unit 17 is activated by activating the motor (not shown) operatively attached thereto. Since the blower unit is preferably of the single speed type, the rate of flow of ambient air drawn from the outside of the enclosure and dispersed in overlapping layers across the interior thereof is controlled by regulatingthe position of damper valve 20.

As the warmed air above heaters 31 begins to rise in convection currents, the cooler exterior air being horizontally dispersed in overlapping layers from the stacked baffies contacts and diffuses such currents to give even, rising heat without hot and cold columns. The heated air, of course, ex hausts from roof opening 32 in the upper portion of enclosures 29.

To regulate and vary the drying or curing temperature within the enclosure or barn 29, all that is necessary is to place a thermometer in the evenly rising mass of air above the diffusing baffies and then either increase or decrease the intake of cooler, outside air by regulating the position of the damper means 20. An alternate manner of controlling the drying air temperature would, of course, be to regulate the B.t.u. output of the heaters 31 while maintaining the outside air flow intake constant. An additional control means would be to adjustingly regulate both the diffuser air flow rate and the heater B.t.u. output.

I The forcing of outside air into the interior of a natural convection-type curing barn has the additionalv advantage of eliminating moisture building, commonly known as'sweating.

.removal of the vaporized moisture decreases the vapor pressure of the drying air, resulting in less heat required to remove a given unit volume of water from the tobacco. Clearly this significantly reduces the drying period and increases the quality of the leaf.

When the drying or curing process has been completed, the diffusing system of the present invention can be quickly dismantled and moved either to a protected storage area or to another treatment enclosure where it is easily set up for the new operation. Thus it can be seen that the device of the present invention is readily portable to add even more to its desirability and utility.

It is obvious that the present invention has the advantage of being inexpensive to construct and is readily assemblable and disassemblable. The present invention also has the advantage of allowing even drying throughout a drying enclosure thereby eliminating both cold spots and sweating of the produce being dried or cured.

The present invention may, of course, be carried out in other specific ways than those herein set forth without departing from the spirit and essential characteristics of the invention. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive and all changes coming within the meaning and equivalency range are intended to be embraced herein.

lclaim:

l. A portable, air-diffusing device employed within a drying enclosure using natural convection currents to remove moisture from the produce being dried comprising: a blower unit means disposed exteriorly of said enclosure; a duct network having a generally horizontally disposed exterior end communicatively connected to said blower means and an upturned, generally vertically disposed interior end; a generally tripod-shaped support means for said upturned end including a duct encircling collar having a plurality of downwardly and outwardly radiating legs removably attached thereto; a plurality of spaced, progressively smaller, horizontally disposed airditfusing baffle means attached to and stacked above the interior end of said network, said baffles being disposed in axial alignment and having progressively smaller central openings therein whereby heated air rising by convection will be diffused to produce even, moisture removing heat throughout said enclosure.

2. The device of claim 1 wherein a damper means is operatively provided within said duct network whereby the volume of exterior ambient air introduced into the interior of said enclosure may be regulated.

3. The device of claim 1 wherein said duct network is readily disassemblable for easy portability from one location to another.

Claims (3)

1. A portable, air-diffusing device employed within a drying enclosure using natural convection currents to remove moisture from the produce being dried comprising: a blower unit means disposed exteriorly of said enclosure; a duct network having a generally horizontally disposed exterior end communicatively connected to said blower means and an upturned, generally vertically disposed interior end; a generally tripod-shaped support means for said upturned end including a duct encircling collar having a plurality of downwardly and outwardly radiating legs removably attached thereto; a plurality of spaced, progressively smaller, horizontally disposed air-diffusing baffle means attached to and stacked above the interior end of said network, said baffles being disposed in axial alignment and having progressively smaller central openingS therein whereby heated air rising by convection will be diffused to produce even, moisture removing heat throughout said enclosure.

2. The device of claim 1 wherein a damper means is operatively provided within said duct network whereby the volume of exterior ambient air introduced into the interior of said enclosure may be regulated.

3. The device of claim 1 wherein said duct network is readily disassemblable for easy portability from one location to another.

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