US1987161A - Hot air furnace - Google Patents

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US1987161A
US1987161A US701501A US70150133A US1987161A US 1987161 A US1987161 A US 1987161A US 701501 A US701501 A US 701501A US 70150133 A US70150133 A US 70150133A US 1987161 A US1987161 A US 1987161A
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pipes
casing
air
disposed
spirally
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US701501A
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Jr Charles M Snelling
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    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24HEATING; RANGES; VENTILATING
    • F24HFLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL
    • F24H3/00Air heaters
    • F24H3/008Air heaters using solid fuel

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  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Heat-Exchange Devices With Radiators And Conduit Assemblies (AREA)

Description

C. M. SNELLING. JR
HOT AIR FURNACE Jan. 8, 1935.
Filed Dec. 8, 1933 4 Sheets-Sheet 1 CHAELE5 M 5NELL/H5JE Jan. 8, 1935'. c. M. SNELLING JR HOT AIR FURNACE 4 Sheets-Sheet 2 v Filed Dec. 8, 1933 CHARLES M SHELL/Mme.
Jan.s,1935.
cf M. SNELLlNG. JR
HOT AIR FURNACE Filed Dec. 8, 19533 4 Sheets-Shegt 3 CHARLES MSHELL/H JQ Jan. 8, 1935. c. M. SNELLING. JR 1,937,161
HOT AIR FURNACE Filed Dec. 8, 1933 4 Sheets-Sheet 4 E5: 5 IHVEr/TORJ fHARLES MSHE LL/N JR air space in the heated portion of the Patented Jan. 8, 1935 UNITED STAT S PTENT OFFICE/d HOT AIR FURNACE v Charles Snelling, Jr.,- Greenville, s. o. f Application December 8, Serial No. 701,501
12 Claims. (arias-109) is generally furnace for. heating buildings and then passed upwardly and spirally through fa compartment while the direct heat from the fire box is passed also through this compartment but separated from the heated air. Ontop of this compartment is mounted a distributing headwhich receives the heated air and distributes it to the various rooms of the building being heated.
Animportant feature of the invention is aspace;
between the heated compartment and thedis- 2 tributing head so that if one of the pipes to a room is rendered inoperative ,that is by the heat being out in that room, the heat will bedistributed to the other rooms and thus injury to the furnace will be eliminated because there will be no dead compartment disposed abovethe fire box. 7
It is another objectof this invention to provide a-hot air furnace having a fire box with anonclosed air space surroundingthe same and a unit mounted above the fire box through which, the flames and direct heat can pass, said unit having a plurality of pipes therein whose lower ends communicate with theair space surroundingthe fire boxand whose upper ends pass through the up per end of the unit mounted above the fire box; also a.distributor casing is mounted above the upper end of the said unitprovidinga compartment between the distributor casing andthe said unit into which the heated. airpassing through.
said pipes empties, andsaid distributor unit has a plurality of pipes leading therefrom and whose lower'ends communicate with said air space above the upper end unit of the device, emptying into" an air spacedisposed below the distributor casing, it is therefore seen that the heatedgair passesinto a common chamber from whence it passes into'the delivery pipes of the distributor casing, andthus it is seen that all of the air will ;not passthrough one pipe because all pipes communicatewith said airspace into which the heated'air is "delivered.
of said unit. In this manner a structure is provided in which it is impossible for,
It is to be understood that the material. from{ which theapparatus is constructed can bechosen to suit-the particular need, for it will be evident that the casing surrounding the fire box could be of a -heavy grade of sheet metal andalsoithe distributor casing and=delivery pipes can be of a' heavy grade of sheet metaL'whereas the middle unit,which is exposedtothe direct action of the heat, asiwell as thefire'boxiwould have to be of.
castiron and the like towithstand the direct action of the heat. l I
It is also to be understood that though I have described thsource of heat throughout, asrb'e'ing a fire box, it is evident that a source of electrical:
heat or oil heat or any other desired heat produc- 5 ing means may be disposed where the fire box is shown in the drawings. I v Some of the objects of the" invention having" been stated, v the invention will appear more if in the detailed description hereinafter following when taken in connection with the accompanying drawings showing a preferred embodiment of invention,,in which:
"Figure 1 invention} ,7 H. n Figure 2.is an exploded isometric view of the inf-Z vention and looking in a reverse direction to thja t in Figure 1;
Figure 3 is an elevation of the invention with 3 parts broken away to show the interior thereof j Figure 4 is a transverse sectional view ta'lreni along the line 4 4 in Figure 3; 1 Figure ,5 is a verticalsectional View taken along line 5 -,5 in. Figure 3 through the central portionof the lower unit of theapparatus; j 7 Figure.6 isa vertical sectional viewtakenalong;
line 66'in Figure 4 showingthe central upper portion of the middle unit of theap'paratua] Referring more specifically tothe drawings,v
10 indicates theouter ,casingof the lower unit having a flange 11 securedaroundthe lower edge, thereof, forming a suitable means for support, though it is understood that any suitable base may be substituted for the fiange v.11. Centrally 4J5 disposed within the casing-10 is a firebox ar rangement in the form of cylinder 12 having a: flange 13 on the interior thereof on, which is mounted a grate 1 4 which is conventional and is rotatable by means of an extension 15 which I may beengaged by hand or a suitable tool after, the extension 15 projects through a slot l5a; the outervcasing 10. v
The, lower portion "ofthe cylinder 1 2 has.,an
opening 16 surrounded by an extension 17 which h is an exploded ,isometrieviw of' thel 5 pertinent to regulate thelamount of airrwhichi flanged alongits. periphery an cured to casing 41.
of spirally disposed. pipes extends through the outer casing 10 and has a flange 18 thereon supporting an ash door 19.
Also disposed above the grate 14 is an opening 20 surrounded by an extension 21 which extends through the outer casing 10 and has a flange 22 thereon supporting a fire door 23.
.Disposed on the inside surface of the casing 10 is an annular trough 24 into which water may be placed through a funnel member 25 for supplying humidity to the heated air.
The casing 10. has opposed extensions 26 and 27 to which-are connected pipes 28 and 29 which pipes form the intake pipes for the air to be heated and passed to the desired rooms of the building. The pipes 28 and 29 may e-xtenel te; any suitable portion of the building for returning the air from the rooms back to the heating: unit.
The pipes 28 and 29 have pivotally rmmnted therein dampers 30 and 31 which have levers 32 and 33 mounted on the exterior of thepipesI-28 and 29 to which operatingmeans such as chains 34 and35'are secured which are extended to any suitable portion of the building for regulating the amount of air drawn intothe compartment betweenmembers 10 and 12; These dampers areli-mitedbystops BG-and 3'7 but it is to be noted that when; the operating means 34 and--35 are -not rig-id thedraift being drawn through pipes: 28 and 29 may rotate the dampers and draw the lower portion thereof inwardlytowardstthe 1 com is drawn into the casing 10. Iii-desired, of:=coursev chains'z34 and 35umayibe replaced: with :ri'gidacon- HBCtiOIIS? sor asv to rigidly control; the dampers- 3o.;and:3 1..
I The upper; portion of cylindrical memberc li hasaral flange: 38 therearound ,v acting; as a* support: for the central portion 01E-v the: plate 4Q -whieh- .fonns thebottom; of the nextunit. V
'Phe next unitwhich ismounted on top ofx cas ing-;-1 .O;and of-which plate=40=forms abottompontion, comprises a; cylindrical portion .41. having. arband 42a welded thereto and which fits. over. the outside of the casing 10.. The plate; 40. is
d is sui-tably se- The plate 40 has alhole. in the center thereof into which. the up i 9nd of cylinder member 12.fits.to form anlair tightjolnt between plate 40 and flange 38. v n
The upper end of. cy1inder'41 is closed. by-a' to the upper surfacev than the cylindric'alportion 4L thus forminga, shoulden44 on the upper end of cylinder 41. V The 40 and 42;. supportv the ends. of a plurality 143' andit is to be 1 101181511 that-pipes 43 at.their upper ends are so disposed that. their cross-sectional. longitudinal axes are radially disposed with regardito 'the,casing. .411
These pipes 43.'are spaced apart from each other to allow the flame and smoke fromxthe firebox to pass therebe'tw'een. By having the pipes 43 arrangedspirally', a greater surface is exposed to the heat generated by the heat producing means than if the pipes 43 werevertically disa posedi It also gives a; swirling motion to the heated" air' which swirlis in a direction'which isit-he same-as the" direction of the outlet pipes 59', hereinafter described, and it is to be notedthat theoutlet pipes were also spirally arranged in the same direction as the pipes 43, wherebythe swirling'motion given-to the heated'air by pipes 43 is continued as the'air, after leaving pipes 43" in a swirling manner,- enters the outlet pipes which-arespirallyarranged [in the same directrally disposed hole therei-nwhich 'isclosed by a tubular portion 45 which projects *downwardly and also projects through the central portion of-.a plate 46. The lower end of tubular portion 4.5,hasenlarged portion 4'7 to which is secured a cone 48.
Thepurpose of the above recited arrangement is to close. the upper ends of the portion of the cylinder which receive direct heat from the fire boxandfthe cone 48 deflects these air currents from the flre box outwardly.
It isto: be noted that plate 46fhas a p1ura1ity. off'opeiiingsw th-rough which the pipes43;,p'a' ss. the openings 50 being somewhat larger tlian the pipesasthese openings 50 form the solepassa'ge.
way-forth'e flames, heatediair-currentsand smoke passing upwardly; from the firebox "12 f Thi's arrangement forces the heated 'airandflames arising from the fireboxi'ztdpass into close contact with thepipes 43 m heat {theai'r' passm therethroughi Secured' to tljie casing- 41 contmunicating with thespace between plates- 42ffand 46 is a Pipe 51 which is connected to a; smoke;
stack; chi'mney the-l-ike, thus completingthef draft arrangement for allowing the smokeii'o'm the fi-reb'oxtb passinto a-suitable chimney, 1
- Adapted t0- flt immediately outside ring 4211011 the upperend'ot'casing 4T which comprises a casing-55- whichhas aplural of radially disposed vanes 56 spaced apart; fro
each other and to theinside-endsof'thesevanes ai cylinder member 5'7 is secured having a centrally disposed opening therein in which is *slidablymounted a' pipe" 58; this pipe being} heldirl: trio? tional' sliding movement within the cylindrical member 57 so tl-ia t-itcanbeadjusted ,vei ticallyb This pipemay be connected" toapipe 'leading tothe central portion of the building-so-that if all of therooms should" be cut off from the" furnace? the furnace would not be damagedbecause the air would pass into the central "portion oif-th'e buildingtowhich pipe 58= leads. I
It is-to=-be--'not ed that thelower ends oranes 56.:do not extend down 'to the plate 42; thus "leava' ingya space" bet'ween the lower eaa or the-vanes This is provided sothat 56 andthe plate 42. whensome of "the pipes leading to" the'frooms fof the building are cut on; to preventj heat from. going. .to these'gparticular "rooms it will not I pre.
vent clrculationpfjfair in the "pipes .43' because all... of these] pipes} ,43. discharge theiriheatedmir into;
is a' distributor-head p m nt between the.plates 42 andthe lower; portion 2 of ,thevanes56 and therefore the 1 heated air willv pass into .the other; pipes :WhlChi are; not-1, disconnected from; their roomsba'ndin caseall pipes were disconnected from theirrroomsy then 'theheatedair would pass through.pipes58 to-the. central portion ofthe building."
Itcis also. to'sbenoted that the vanes 56 form the bottom portion oi the discharge pipes 59 -where as,'a shorter vaneBO; (see me; 3) forms thefuppe'r side of the pipe 59*and is joined as at" 61 to the. lower surface to the next succeeding-variebfi;
thus forming-the plurality oi? pipes o w rounding pipes 43 and into the, compartment between plates 42 and 46 and from thence passes are secured suitable piping which leads to the various rooms of the building. r
It is to be noted that pipe 58 can be adjusted vertically todetermine the. amount of air which is allowed to be conducted'to the central por-- tion of the building and of course a suitable damper, not shown, can be provide'din'the building forcutting'ofi the pipe 58 entirely and forcing the heated air through the pipes 59 is desired.
Method of operation 43 into the compartment immediately above plate 42 and passes into the pipes 59. It is. noted that when anyone of the pipes 59 is disconnected from the room, to which it leads, the air will pass into the other pipes which will still establish a circulation through all of the pipes43 because it isdischarging into a common compartment disposed between casings 41 and 55. j I
The heat draft arising from the source of heat in casing 12 passes'upwar-dly into the central portion of casing 41 and is forced outwardly'around pipes 43 and passes through theopenings 50 surthrough pipe 51 to the smoke stack. This causes the air passing upwardly through pipes 43 to be; further heated by this draft and it is to be seen: that a large heating surface is account of the arrangement of the pipes 43.
Another important advantage is that if the pipes59 were directly conn'ectedlto pipesl 43;-;and if the damper of a particular room wereclosedit'; would prevent circulation of air upwardly through that particular pipe Y43 and the heat fromthe fire box would damage that particular pipe, but ;on account of all of the pipes 43 discharging into a common compartment it is seen that in case any pipe 59 is closed that theother pipes will take the heated air to the other rooms and thus all of the pipes 43 will have air circulation therethrough at all times. I
Another important advantage of this invention is that it provides a much greateramount of heating surface to the size of the furnace than is present'in any furnaces heretofore developed. 1
The position of pipes 43 can be varied in.
accordance with the heating surface" desired.
' They can be arranged vertically or can' bearranged in flat spirals to secure a greater heating of the air passing therethrough. The pipes.43.
can be round, oval or of any desired shape,.the
drawings being merely illustrative of. oneform of p of other spirally arranged the invention.
'In the draWingsand specification there has been set forth a preferred embodiment of the invention, and although specific terms are employed, they are used in a generic and descriptive sense only, and not for purposesof limitation,
the scope of the invention being setforth the appended claims.
I claim: I
1. A heating unit comprising a base member, a
heat producing unit disposed within the base and of substantially smaller dimensions than the base thus forming an air chamber between the base and the heat producing unit, a middle unit disposed on top of the base and having a pluprovided on rality. of spaced and spirally varranged pipes therein, the lower ends of thepipes communicating with th'e'space between the heat producing unit. and the walls of the base member, a third unit fitting onto the upper end of the middle unit and having a plurality of pipes leading'upwardly and spirallytherefrom and spiralled in the same direction as the. other spirally arranged pipes, a pair of header plates closing the upper and lower ends of the said second unit, the two header plates in said second unit having the spirally arranged pipes communicating 'therethrough and a draft vent extending from the .upperportion' of said second unit immediately below the header plate in the upper end thereof;
2. A hot air furnace havinga fire box and a casing disposed around the fire box and forming an air space between the casingand the fire box, a middle casing disposed on the upper end of the first casing and closing theupper. end of said air space, means closing the upper and lower ends of the middle casing, the lower end of the middle ca'singhaving av hole thereinv into which theupper end of the fire box is fitted, a plurality or spirally arrangedspipes extending entirely through the middle .casing and having their lower. ends communicating with the air space in the first casing, a draft vent communic'atingwith theeupper portion of'the sidewall of the'rniddle casing, a distributing casing mounted on the upper end of the middle casing and 'havinga plurality of spirally arranged pipes spirally arranged in the same direction as the first mentioned spirally arranged pipes and extending therefrom and having their lower ends spaced from'the upper ends of said pipes in the middle casing.
, 3. A warm airffurnace havingafirebox and a casing'surrounding the fire box and providing an air heatingspace between the casing and the firebox, a second casing disposed over theupper end of the first casing a header plate closing the upper end of the second casing,.an,annular merit-- ber closing the outer/portions of the lowerv end of thesecondcasing, a distributor casing disposed over the, upper end of the secondcasing and having a plurality of spirally arranged pipes extending therefrom and open attheir upper and lower ends, a plurality .of pipes in. the secondcasing spirally arranged in the same'direction as the first mentioned spirally arranged pipes and com municating through said header plate'andsaid annular member, a draftjvent in the upperjside' portion of the second casing, the heated air pass ing through said spirally arrangedfpipesfand through said distributor casing and, the draft,
through the fire box passing centrally upwardly and then outwardly through, said second casing. A' warm air furnace having a plurality of,
and having a plurality distributing pipes dis,- posed above the upper'ends of the air pipes and extending in the same directionas the first menspirally arranged air pipes tioned' spirally arranged pipes,'the lower ends of, the distributor pipes'stopping short of the upper ends of the air pipes to form a compartmentfor' the air after passingthroughthe air-pipes and.
before the airjenters the distributor pipes, and
means for heating the exterior, of the air pipes.
to heat the air passing therethroughp 51A warmair furnace having a'fire box and an enclosed air space surrounding the fire box, a casing closing the upper end of the air space but communicating with the upper end of the fire box, a header plate closing the upper end of iii 4 the casing a distribiitoi casing disposed n-tfie upper end or the casing, a plurality' of spaced and spirally "arranged pipes in"the""flrst-=named casing communicating with the air space. at their lower ends and through said header 1 plate with the dstributor casing at their upper ends, a disk intermediate the ehd s o f the first name'd casing and having a: plurality of holes' therein larger than the pipes and through which the pipes are passed, the distributor"casingihaving a plurality of' pipes arranged therein spi'ralled' in the same direction as the firstspirallyjarranged pipes and whose lower endsar'e s'pacedfrom the upper ends of the first spirally arranged pipes 'andiforming an air chamber between the ends of the two sets of pipes, whereby flames and products ofcombustion are adapted to pass around said flrst pipes and through said openings in said inter mediate disk; and a draft vent in the" sidewall of the casing and communicating with'tne space above said intermediate disk.,
6. A warm air furnace hav ng acasingprovided with a plurality of spirally arranged" pipes therein, means for heating the exteriorjof said pipes,
means for conducting air tobe heated through said pipes, and spirally disposed. means extending :in the same direction as'the first spirally arranged pipes for conducting the heated air in divergent directions after it leaves'said' firstgpipes. 7; A warm air furnace comprising 'a casing", fa'
plurality of spirally "arranged pipes passing through said casing, means for supplying partial- 1y heated air to the lowererids ofsaid pipes, a distributing casing enclosing the discharge ends,
- ofxsaidpipe's and having spirally'jarranged' dis-1 tributing pipes extending inthe same direction as the first spirally arranged pipes for distributing theair' after'it has passed through said first h pipes, the distributing casing forming a compart:
" ment immediately above the upper ends of said I I v I trically arranged hot air pipes spiralled in the. same direction as the said spirallydisposed pipes,
first pipes. 8 A warm air furnace comprising a source of heat, a casing surrounding'saidsource and form'- ing an enclosed air space surrounding;saidsource,' a second casing disposed above said source and;
having" afplurality 'of spirally arranged. pipes passing therethrough, the lower ends of said pipes communicating withsaidlencl'os'ed air space, a
; distributor casing having a plurality of other spirally arranged pipes therein extending in the same direction as the first spirally arranged pipes, surrounding theupper end of said second casing and forming an enclosed ,air' spacefabove the upper end of said second easing into which the" upper ends of said pipes discharge air, a
draft vent in said second casing and a plate dis posed in said second casing below said draft vent and having openings therein larger" than the pipes through which openings said pipes are led wherebyj draft currents from said source are passed in close proximityto the exterior of said pipes.
9. A warm air furnace comprising a me box a casing surrounding theflre' box: and in spaced relation thereto forming an air space between the firje'rbox'and the'casin'g, a second casing disposed above the first casingand closing the upper end of the first casing but leaving the upper end of the fire box open,- a header plate closing the upper 'end of the second casing, a plurality of spirally Lab al-ti arranged pipes" having" their 'u pertgnds conii-v munic'ating through'said' header plate in 'theupper end of the second casing and having, their lower ends in communication with the air space surrounding the iire box, a distributor head mounted ontop of the first casing andforming an 'air space between the upper end of the second casing and thedistributor casinginto which the airpa's'sing, through said pipes enters,la draft outlet in the sidewall of the second casing and means for directing the flames and heated air from the'fire box in close proximity to theouter' surfaces of said pipes and outwardly through the said draft outlet, said distributor head having discharge p'pes spirally rranged in the same, direction as the said spirally arranged'pipes. I
10. Iri awarm air furnace, a centrally of the furnace and having a passage way thereabove for the products of combustion,
a'casing surrounding the me box and formingan air space around'the fire box; a casing disposed for receiving air drafts, from said pipes; a draft outlet in said second casing for directing the direc'tiorras the said spirally arrangedpip'es. 11'. A hot air furn a'ce c omprisingi upper, lower and middle casings; disposed fend on end, afilre v b'o'x centrally disposed in the lower casing and having" m Open upper end'fimean s closing the; ends of the middle casing; a plurality ofconc'en t'rically arranged and spirally disposed pipesjin' the middle casing and penetratingfthe ends thereof;
the casin ghaving a piuralit j f concen.
112. A 'hot' air furnace comprisinga base; a
box disposed concentrically of said" base and hav ing its upper end open, an intermediatecasing mounted on the upper end of said base and'closingthe upper end: of the base except the'fire box, a closure for the upper end of said intermediate casing, a plurality of spirally arranged pipes concentrica'lly arranged ,in said intermediate casing and passing throughthe upper andl'ower ends or "said intermediate casing, anfexhaust pipe .penetrating the sidewall of said intermediate casing,
a top mounted on theupp'er end of said inter mediate casing and having a plurality'of hotair pipes spirally disposed therein and ,extending in the same direction asthefirst spirally arranged products of combustion from the firebox upwardinsaidsecond casing'and against and around the said pipes thereinj said distributor head hay-i ing-discharge Dibesspirally arranged the'same' firebox disposed pipes, the lower ends of said hot air-'pipesstoppin'g' short of the upper ends of said pipes in said intermediate casing to form an air space between the two setsof pipes.
CHARLES M sNE uNG, JR.
US701501A 1933-12-08 1933-12-08 Hot air furnace Expired - Lifetime US1987161A (en)

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