US2651293A - Humidifier boiler - Google Patents

Description

Sept. 8, 1953 E. W. BOTTU M HUMIDIFIER BOILER Filed March 16, 1949 IN V EN TOR.

EDWARD W. BQTTuM A TTORNEY Patented Sept. 8, 1953 HUMIDIFIER BOILER Edward W. Bottum, Detroit, Mich., assignor to Skuttle Manufacturing Company,

Detroit,

Mich., a corporation of Michigan Application March 16, 1949, Serial No. 81,809

Claims. 1

This invention relates to a vaporizing apparatus for discharging vapor into a gaseous medium and more particularly, but not exclusively, to a humidifier in which Water or other vapor may be discharged into an air mass in quantities controlled by variations in the calorific output of a heating unit.

It is well known that air heated by a conventional furnace, or other heating unit, has a relatively low humidity which is both uncomfortable and unhealthy. Many humidifying devices for heating units have been previously suggested and used. For the most part, the devices have been incapable of providing the necessary degree of humidification for the air and also have been incapable of rapidly and suddenly changing in response to changes in the heating output of the heating unit. For these reasons, the prior humidifying devices have proven unsatisfactory.

Most frequently the conventional humidifying apparatus employed consisted of an open pan or receptacle of water positioned either within the heated rooms or within the air chambers of the furnace itself. Humidifiers of this type are not satisfactory for use under many conditions. Due to the high heat of vaporization of water, substantial heat is removed from the surrounding air by this type of humidification. Various methods for increasing the water vaporization in water pans or receptacles has been employed such, for example, as increasing the effect of vaporization surface of the Water, by the use of absorbent fins or plates, or by increasing the temperature of the water in the receptacle. While these methods have increased the vaporization rate, the increase has in some instances been in sufficient to provide the desired amount of humidification; heat is still absorbed from the surrounding air to evaporate the Water; and in addition, the amount of humidity supplied to the air cannot be accurately controlled to compensate for sudden changes in the heat output of the furnace. In the prior humidifiers wherein the Water is heated, such as by heating coils, a substantial quantity of water must be kept in the receptacle at all times in surface contact with the heated air. For this reason the water cannot be heated or cooled quickly to suddenlychange the vaporization rate and consequently compensate for sudden changes in the temperatureor 1 volume of the heated air.

With the humidifying apparatus of the present invention, water. is metered to a steam chamher in proportion to the evaporation rate within the chamber, which in' turn is in proportion to the heat of the gases in the furnace flue. The apparatus includes a water reservoir positioned outside the heated portion of the furnace, a heat transfer unit positioned within a heated portion of the furnace, preferably within the furnace flue, and one or more absorbent plates extending from the water in the reservoir into a steam chamber provided in the heat transfer unit. In operation, no liquid Water is present within the steam chamber except that which is present on the surface of the absorbent material. The rate of flow of water to the chamber is thus dependent solely upon the rate of vaporization of the water from the surface of the absorbent plates. Any number of absorbent plates may be employed to provide a suflicient flow for maximum vaporization rates within the chamber.

The steam generated in the steam chamber is directed into the heated air by any suitable means. If desired, forced circulation may beemployed such as by the use of a centrifugal blower toforce the steam from the chamber into the heated room, or if desired, into the furnace hot air ducts.

Prior humidifiers which are dependent upon currents of heated air to absorb the moisture and carry it into the area to be heated, are of no value in heating systems utilizing hot water or steam as the heat exchanging medium in radiators or the like located in the area to be heated. The efficiency of such heating svstems is well known but the difficulties in providing suitable humidification in areas heated thereby have reduced the demand for such heating systems.

It is therefore an object of the present invention to provide a vaporizing apparatus which may be used with any type of heating system to supply and discharge vapor into the air in an area to be heated in cuantities necessary for maintaining a uniform and satisfactory predetermined volumetric concentration of the va or which will vary automatically with the heat output of the heating system.v

It is another object of this invention to provide a humidifying apparatus which will supply water in vaporized state to heated and relatively dry air and will automatically and quickly vary the water vapor output to the air in accordance with the heat output from the furnace.

Still another object is to provide an apparatus which is sensitive to small variations in the heat output of the furnace whereby a relatively constant humidification of the air may be obtained.

Another object of the invention is to provide a humidifying apparatus in which only a small quantity of liquid water is present within the steam chamber on the surface of the absorbent plates in order that the steam output of the apparatus may vary rapidly with small temperature variations within the chambers.

Another object of this invention is to provide a humidifying apparatus havingsameansto force the flow; of .-water vapor fromi-the' steam: chamber into the relatively dry air of the area to be heated.

Other objects of this invention will appear'in the following description and appendednclaims, reference being had to the. accompanying...drawings forming a part of thespecificationwherein like reference characters designate corresponding parts of the several views.

In the drawings:

Fig. 1 is a front elevation of the humidifying apparatus embodying the features of the present .inventiornand .showing the water.chamber.in

section. .andalso showing a portion ..of.'..the cover plate broken-away. for .clarity:

(Fi 2 isa sectional view: taken substantial ly on the. line," 2-2 .ofJFieu- 1; and

Fig. 3. isa. reduced fragmentary sectional view showing anmodification ,of' the humidifying. ap- .paratus ,of .thepresentinvention.

Before. explaining thepresentlinvention" in "detailitisto beunderstood thatlthe invention'is .not limitednin -its .iapplication to the details. of

construction and .arrangement .of ..parts .illus- .tratedinthe. accompanving. drawin s, ,since the .inventionds .capablesofpther embodiments and of being..practicedoncarried out. in various ways.

-Also it .is. to"- be .understood. ithatjthe. phraseology or terminolo y employed;herein'isiorthegfiurposeof descriptioniandenohofllimitation.

.The. humidifyingsapparatus I I) -of. thepresent invention. is .shown.in,l=igs.-1 vand.;2 of ,thejdrawsings-in,assembledrelation with anlassembly plate .12 and anwater-..chamber..l 3 having a.-,standard .type float control-ILtherein. .The .humidifying apparatus 10 comprises essentially the heattranstier-- unit. I.5 .having. a.-steam..chamber .1 6f therein, .awater reservoir, 1 I and. a plurality of .absorbent s-plates I8 rextending .from .the .-water ['9 -in .the .reservoir .into the -steam-. chamber .I 6 ..provided in the heat transfersunit.

1-As r shown .in. the drawings, ,a--.unitary hollow member forms both .;the rectan ular -.-heat sexchanger .-unit, includingi the: fins .20 and .the soylindricalbody-portion.- 2 I of. the Nl'fitBIExBGSGHlOiI'.

The; hollow -member.,is formedof .a Anon-corrosive heat. conductingz-material suchaaaluminum and-is preferably of a cast construction. .Oneend ofthefsteam chamben opens into thewater reservoir, butis positioned.-above..the .normal .level of the PWaterWith-insthe; reservoir. .Thewater. is carried bycapillary. action withinthe absorbent plates ts from. :the I reservoir I! into .the -steam --chamber. and; anyexcess .water .in .the. chamber such as by condensationpfthemater .vaporwill fiowbygravityback into therreserv-oir I I.

Theopemendof .the .body ;portion ,2 I of .the :reservoir I! is provided. withmpair. .of transverse iianges :22. .A- coverplate..23 encloses the .open -end-of thebody portion and is removablysecured thereto by -a-.pairofscrewsifi threadeddnto the transverse flanges -12. :Thecover-plate ,is-provided-with .an; annular .flangeliiwhich. seats on the outer. periphery. .ofthe .body portion; 2 I. An annular. gasket 26-is positioned withinthe flange 25=and seals the open-end. of. thewatenreservoir. An outlet port.-21 is formed in-a threaded ,boss 28 located in the top of the body portion 2| and 4 communicates with the steam chamber. Vapor is led from the outlet port 21 through the conduit 21a which discharges into any desired area. The threaded boss 28 is provided with a thread- 5 ed nut 29 which with the packing 29a provides a vapor tight connection with the conduit 21a. The water chamber is also. provided with a downwardly depending water inlet port 30 having an opening in one end thereof connected with the conduit 3i extending from the water chamber I3. "The opposite end of the water inlet port and also 'fithesheat exchanger unit I4 are each provided witha threaded plug 32.

iThe'a-bsorbentzplates I8 are generally L-shaped .15 ;;and-are supported vertically within the steam chamber I and have the short arm portions I80, .extendingzbelowithe liquid level line I9. The ,plates are preferably formed of compressed glass fibers or'the like having a porous structure providing a plurality of capillary spaces in which "the liquid may riseby capillary attraction from the -reservoir I'l into the-"chamber *IB. In-"op- -erat-ion" the liquid on thesurf ace of theabsorbent plates 18 is evaporated by the heat given up by theheat conducting walls'ofthe heat exohanger and -is discharged into the relatively 'dry "air through the outlet port 21. -'Asshown in the drawings,"-six'plates have been'found suitable for mo'st humidifying purposes. However, any numberof absorbent plates I8 may be employed in 'the apparatusas desireddepending upon the liquid to be evaporated, the extent of dehydration' and thevolume of the'a-irto be'humidified.

The waterlevelin the waterreservoir is conitro'lle'd" and maintained by the water'level in the water chamber, which in turnis 'controlled'by the float control mechanism I4. The latter -mechan-ism"-includes a plunger valve 33 for controlling the'fiow :of water into the water cham- -"ber"and is operated'by the-float through the 'connectingarm flfiandthelink 36. 'The arm.

."flblY supported on the-'U-shaped'bracket 38 by the'thumb nut 39. The bracket 38has an end portion-40 rigidlysecured to the adjacent inner wall *of" the water chamber.

.The" float. 3 4 'may be manually operated to open ".thetvalve '33 bythefioat control arm ll. The latter issupported by thewater chamber cover dtandds pivotally secured intermediate the ends .of "the -controliarm 4| to the angle bracket '43 mounted onthe cover.

:IIhe float control arm 4| is provided with a "handle portion .44 extending through a longitudinal slotztherein'and the lower end 'ofthe controlarm is twisted to. provide a transverse portion 45 which isadapted to engage the float ;arm35 upon upward movement of the handle portion ofthe control arm. An overflow pipe 45 is also. providedinthe water chamber I3.

The assembly. plate. I2 is shown comprising a ,pair .of plates,..each plate .of which has one end secure,d -.as.at .41 to the body portion 2!. The .other .end 48 voreach plate is..curved.inwardly .ltdconform to the external contour of. the metal -flue. .ofany. conventional. furnace.

A .modificationof the invention is shown in .Eig. .3-in.which a centrifugal fan. is mounted .on the end platelifl secured to the water reservoir H. 'The centrifugal fan is driven through the shaft .5Lby the motor =5.Z;secured by any'suitable means onthe outside of the cover plate 50. .Thelatter is.,provided with'an annular air'inlet I .opening .53 in the low pressurearea "adjacent the axis of-the shaft.

With the present apparatus, the heat exchanger, preferably extending into the flue of the furnace, is heated by the combustion gases within the flue in proportion to the temperature of the combustion gases. The heat generated within the vaporization chamber therein vaporizes the liquid on the surface of the absorbent plates and discharges the vapor into the area to be heated in quantities necessary for maintaining a uniform and satisfactory predetermined volumetric concentration of the vapor. The quantity of vapor generated in the vaporization chamber will thus vary automatically with the heat output of the heating system.

The vaporizing chamber is positioned above and opens into the water reservoir whereby any excess liquid present within the vaporizing chamber, such as due to condensation, will immediately return by gravity flow to the reservoir. For this reason, the only liquid present within the chamber is the small amount present within the absorbent plates and on the surfaces thereof so that the apparatus will operate quickly to vary the vapor output to the air in accordance with the heat output of the furnace and is sensitive to small variations in the heat output thereof.

The vapor generated in the vaporization chamber is dis-charged into relatively dry air through a discharge port in the vaporization chamber and thence through any suitable tubing. While the water vapor may be injected into the warm air ducts of a hot air system, the apparatus also is particularly adapted to discharge the vapor through a tubular conduit directly into the heated area or heated rooms. The apparatus is therefore well adapted to provide sensitive and efficient humidificaticn for an area heated by a. hot water or steam heating system.

It is to be understood that any desired type of liquid may be employed to provide the vapors which are to be diffused. For example, a liquid therapeutic agent, such for example as a glycol may be used, either with or without water and vaporized by the device of the present invention to provide a vapor which may be diflused throughout any desired area.

If water is used as the liquid, steam is generated and is used as the humidifying agent. It

has been found also that a portion of the steam generated may be discharged into the furnace stack to aid in cutting down the amount of smoke discharged through the flue.

Having thus described my invention, I claim:

1. A vaporizing apparatus for maintaining a desired vapor content in a gaseous medium, comprising a heat exchanger adapted to extend within a heated portion of a heating unit and having a closed vaporizing chamber therein disposed Within the heated portion of the heating unit and provided with a vapor discharge port communieating with the gaseous medium exteriorly of the heated portion of the heating unit, a liquid reservoir mounted exteriorly of the heated portion of the heating unit and adapted to contain a volatile liquid, an absorbent liquid metering member having a portion immersed in the liquid in said reservoir and another portion extending into said vaporizing chamber to meter the liquid from said reservoir at a rate substantially proportional to the rate of evaporation of the liquid from the portion of said member extending into the vaporizing chamber of said heat exchanger, and means to prevent the accumulation of liquid in said vaporizing chamber in excess of the liquid retained by said absorbent metering member.

vapor discharge port communicating with the atmosphere exteriorly of the heated portion of the heating unit, a liquid reservoir mounted on theoutside of said heated portion of the heating unit and adapted to contain a quantity of liquid water, an absorbent liquid transfer member having a portion immersed in the water in said reservoir and also having a portion extending into said vaporizing chamber, said member metering the water from said reservoir at a rate substantially proportional to the rate of vaporization of water within said heat exchanger, and means to prevent the accumulation of liquid water in said vaporizing chamber in excess of the liquid water retained by said absorbent liquid transfer member.

3. A humidifying apparatus in accordance with claim 2 and further characterized in that said absorbent member comprises plates having a structure including a plurality of capillary spaces whereby the water is metered to said chamber by capillary attraction through said plates at a rate substantially proportional to the rate of vapo'rization of water within said heat exchanger.

4. A humidifying apparatus for maintaining a desired moisture content in the atmosphere of an enclosed space, comprising a heat exchanger adapted to extend into a flue of a furnace and having a steam chamber therein disposed within the flue and provided with a steam discharge port to communicate with the atmosphere exteriorly of the flue, a water reservoir mounted on the outside of said flue and adapted to contain a quantity of water, an absorbent plate having a portion adapted to be immersed in the water in said reservoir and also having a portion extending into said chamber, means for maintaining the water within said reservoir at a constant level, said plate metering the water from said reservoir at a rate substantially proportional to the rate of evaporation within said heat exchanger, and means to prevent the accumulation of liquid water in said steam chamber in excess of the liquid water retained by said absorbent plate.

5. A humidifying apparatus for maintaining a desired moisture content in the atmosphere of an enclosed space, comprising a heat exchanger adapted to extend into a flue of a furnace and having a steam chamber therein disposed within the flue and provided with a steam discharge port communicating with the atmosphere exteriorly of the flue, a water reservoir mounted onthe outside of said flue and positioned below said steam chamber, and a Water absorbent plate having a portion immersed in the water in said reservoir and also having a portion extending into said chamber, said plate metering the water from said reservoir at a rate substantially proportional to the rate of vaporization of water within said heat exchanger, said heat exchanger having an opening at the bottom of said steam chamber and communicating with said reservoir, the bottom of said heat exchanger being above the level of the water in said reservoir whereby condensation within said steam chamber will return by gravity flow to said reservoir.

ifihethumidifying' apparatus: for maintainingra edesired :nioisture :content: in:the:atmosphere of ean z-enclosedrspace comprising a .hollow member cof;:heattconducting1 material having :an opening zatoonewnd'thereof, the closedendportion of said :ho'llow :memberzforming a steam chamber @and -=being=radapted ton-extend into a'heated portion cofriafheating unitaa cover-plate for closingthe npening end of :said hollow member'and cooperatfingztherewithz-to provide a water reservoirposiitionednexteriorly:of the heated-portion .of the sheating unit below said steamchamber where- "iby waterfcondensation within the latter :will return :by:=;gravity now to the reservoir and an :absorbentgplate positioned withinsaid hollow .mem- :ber zandsextendingirom said steam chamber to 1saidrreservoir =whereby water within the latter is meteredtozthe steam chamber in; proportiontto ithe iratevof vaporization within said chamber,

z-said hollow member having "a steam discharge sport adapted" to. communicate with the eatmosrphere.

7. 2A. humidi fying apparatus for maintaining-a desired moisture content in the atmosphere oil-an -:enclosed space .comprisinga hollow member of zheat conducting material having an opening'at -one'end thereof,-the closed end portion ofsaid hollow member forming asteam chamber having external heat conducting fins and being adapted -toiex-terrd into-a heated portion of a, heating unit, -a.-cover,plate'for closing the open end of-said holt.low member and cooperating therewith to provide a water reservoir 'positioned'exteriorly of .the heated :portion of the heating unit and be- -low-said steam chamber, means for maintaining the-water :level inesaid reservoir below thebot- ,tom of saidsteam chamber whereby watercondensation-within the latter-will return bygravity .-flow-.to.the reservoir'and an absorbent plategpositioned within said -hollow member and extend- .ing from-saidsteam chamber to said reservoir whereby water within the latter ismetered to the steam'chamber in proportion to the rate ofva- .por-ization "within 'said chamber, said hollow member having a steam discharge port adapted .to communicate with the atmosphere.

.8. A'humidifying apparatus for'maintaininga desiredrmoisture content in the atmosphere of .an enclosedspace comprising a hollow member of heat .conductingmaterialhaving an opening at one end-thereof, theclosedeend portionof said vhollowlmember l-forming 1a steam chamber and being adapted to extend into a heated portion .of 1 a heating unit-a coverplate ior'closing'theopen end of said hollow member and cooperating "therewith tozprovideawater reservoir positioned ,exteriorly of the heated portion of the heating .unit and'below said steamchamben-means to ,maintain the water-level in-said reservoir below .thebottom-of said steam chamber whereby .water condensation within the latter -will .return by qgravityfiow to the reservoirend an absorbent sL-shaped platepositioned within said hollow niember,-.- one. endof" said L-shaped plate' extendingeinto said'steam chamber and the otherrend thereof extending into thewater within said reservoir whereby water within the latter is me- .tered-to the steam chamber in proportion tothe .rate -of vaporization within said chamber, said .hollow -member. having 1 a steam discharge port :adapted to communicate withthe atmosphere.

.9. Ahumidiiying apparatus: for maintaininga desired moisture -.content in .the 7 atmosphere of an enclosed-space comprising alhollow member "ofheatcondu-cting-material having an opening at one 'endthereoi-the closed end portion of said'hollowtmember forming a steam chamber :and being adapted to extend 1 into a heated portionwf-a-heat-ing unit, acover plate for closing "the :open i end :of said hollow 1 member and cooperating therewith to provide a water. reservoir positioned :exteriorly 1 of :the heated :portion 101? the heating: unit and: below saidsteam chamber,

zmeanseto ma-intain the water levelin said reservoirrbelowz the bottom of saidsteam chamber, a :plurality of :qfilates eeach positioned withinsaid 11 member and extending from said steam :chamber to said reservoineach of saidplates 20:-

Hillary's-spaces wherebyithe water within the :reserhaving Iastru-cture including a plurality of-capron is .metered by capillaryattraction ,-to the steamwhamberin; proportion tothe rate of vaporization -within :said chamber, said .hollow member"- having a: steam dischargeport adapted .toicommunicate with the atmosphere, andmeans to prevent the accumulation of liquid water-in saidsteam chamber in excess of the liquidwater :retained bysaidplates and to'permit the --return of-any water-condensation by gravity flow to said'reservoir.

10. A- vaporizing apparatus for maintaining a :desired-vaporcontent in a gaseous medium, comprising a heat exchanger having a closed vaporizing chamber :adapted to bezplaced in heat =exchange-relation with a :heated portion of a :heatingnnid-said vaporizing chamber communi- =cating with the gaseous mediumexteriorly of the heated portion'of theheating unit,'-a liquid .reservoirwmounted out'of heat exchange relation with the-heated: portion ofthe heating unit and adapted-to containta volatile liquid, an absorbent liquid-metering member having a portion im- .mersed in the liquid in saidreservoir and another portion extending into said vaporizing chamber to meterthe liquid from said reservoir at a rate substantially proportional tothe rate of vaporization of the'liquid from theportion of said chamber extending into the vaporizing chamber of .said heat-exchanger, and-means to prevent theaccumulation of liquid in saidvaporizingsehamber iii-excess of the liquid retained by said absorbent liquid metering member.

EDWARD W. BOTTUM.

References Cited in the file of this patent UNITED STATES'PATENTS Number Name Date 1,058,808 Thilges Apr. 15, 1913 1,158,553 Phelps Nov. 2, 1915 1,817,357 Fisher Aug. 4, 1931 "1,907,104 Hall May'2, '1933 2,032,553 Spoelstra Mar. 3, 1936 2,113,024 Ireland Apr. 5, 1938 2,133,599 Turney Oct. 18, 1938 2,171,691 Geisler Sept. 5, 1939 2,427,531 Kuenhold Sept. 16,1947

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