US757520A - Hot-air heating-furnace. - Google Patents

Hot-air heating-furnace. Download PDF

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US757520A
US757520A US18892300A US1900188923A US757520A US 757520 A US757520 A US 757520A US 18892300 A US18892300 A US 18892300A US 1900188923 A US1900188923 A US 1900188923A US 757520 A US757520 A US 757520A
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air
chamber
fire
box
ash
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Edward A Tuttle
Arthur C Tuttle
Herbert B Tuttle
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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

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  • My invention relates to hot-air heating-fur naces of the kind usually set in brickinclosv ures for causing circulation'of air for heating about the're-box to be heated and being of quadrilateral form; and it comprises improvements in the construction of the fire-box to facilitate simplicity and cheapness of construction, effective and reliable self-feeding .and regular combustion of the fuel, and also effective communicationof the air for transmitting the heat, with the heating-surfaces of the fire-box to be heated, as hereinafter described, reference being made to the accompanying drawings, in whichy Figure 1 represents a central sectional elevation of my improved furnace.
  • Fig. 2 represents a transverse vertical section on line 2 2 of Fig. 1.
  • Fig. 3 represents a horizontal section on line 3 3 of l.
  • the fire-box A is formed of two equal and.
  • the coal-magazine is provided with a door f for closing while the furnace is working.
  • the ash-port is also provided with a door, as g; but it willhave the usual air-inlet opening andA regulating-valve for controlling the draft.
  • a sloping grate 1' is arranged in line with the bottom ofthe coal-magazine for re- -ceivingthe coal therefrom, said grate terminating a little short of the rear end of the ashpit and also a short distance above the bottom of the ash-pit and leaving an open throat for the settling ofthe ashes, cinders, and clinker down into the ash-pit as the collections are Y raked forward from time to time, said throat being in such proximity to the bottom of the ash-pit that kindling placed under the throat to begin with will choke the throat and obstruct the fall of the coal subsequently charged into the magazine and will occupy the most ⁇ favorable relation to the coal for starting the tire, and as the kindling burns
  • the tire-box is wider than the magazine and the grate, as seen in Figs. Qiand 3, and in the recesses of the sides of the re-box within the magazine side plates le are set up to support refractory material for the protection of the side plates ofthe iire-box from excessive heat, said side plates being inclined correspondingly with the inclination of the grate and reaching from the front plate of the fire-box backward and downward to the backplate, which is preferably formed on an inward incline Z from about the height of the side plates or alittle higher to the top of the ash-pit. As this part of the back plate will usually be protected by ashes and cinders from. excessive heat, refractory lining of it will probably not be needed; but such lining may be applied, if desired.
  • the height of the side plates 7c will bea little more than the depth of the fire-bed. They are flanged, as at on, on the insides to facilitate holding the clay or other lining ofA refractory material, said iianges preferably ranging lengthwise of the plates.
  • These side plates are also flanged or ribbed on the back crosswise, as shown at n, to otiset the platesa little from the side plates of the re-boX and form fine-spaces c in, communication with the air-space under the fire-grate to supply air above the ⁇ ire-bed, and dampers p are located above these fines to graduate the supply of' air Vas required, said dampers having their pivot-rods q extending upward through the front of the furnace suitably for manipulating them.
  • These side plates have their ends beveled correspondingly with' their inclinations relatively to the side walls of the firebox on which they rest, and thus are supported in their positions, being insertible and removable at will without. the manipulation of any fastening devices, except it may be preferred to use a couple of stove-bolts, as g, to prevent them from toppling over.
  • the grate j is detachably supported on lugs s, projecting inward from the lower ianges m of these side plates,with the lower cross-bar 1f of the grate extended into notches u of said flanges to prevent the grate from slipping downward.
  • the lining of the side plates may have to be notched a little at the notches u ofthe lower flanges m to facilitate the engagement of the said projecting ends of bar with saidl notches u.
  • the fire-box isp'laced in a brick inclosure Q), in which it is supported on abutments w, and in the front Wall where the ash-port and magazine project through it with intervening space for causing effective contact of the air for transmitting the heat with the plates of the tire-box for being heated.
  • the air enters to this space hereinafter called the secondary air-chamber, through inlets y of the inclosure o and is conducted away from the top, as usual, through conductors e.
  • Another brick inclosure 2 surrounds three sides of inclosure 'u and includes an air-space 3, hereinafter called the primary air-chamber, into which the air for heating is received at 4, wherefrom it passes along the walls of inclosure o to the inlet-passages y and is heated thereby to a considerable extent before enter'- ingthe hot spaces of the secondary air-chamber m next to the fire-'box
  • the air in primary chamber 3 is also furtherheated by flues 5, located therein and receiving the hot products from the ⁇ ire-box through pipes 6, communicating with the fire-box at e and passing through walls o.
  • the lues 5 discharge through branch pipes 7 into the smoke-pipe 8, which connects with the chimney, as usual, for discharge into the air, said pipe 8 being located in the cold-'air inlet 4 for giving up as much as possiblefof the heat of the waste products before escaping.
  • the iiues are made wide and shallow, as represented in Fig. 2, for affording large area of surface exposure proportionately to the volume capacity for economy in heating the air by contact, which is known to be the essential way, as it does not absorb radiant heat.
  • the smoke-fines are. arranged horizontally along the sides of the fire-box in primary airchamber 3, and the discharge-pipe enters the chimney at about the same level, and the incoming cold air is carried along in the opposite direction, iirst coming in contact with the outgoing end of the smoke-pipe.
  • BafHe-plates 9 in chamber 3 under iiues 5 cause the incomingair to flow along and in contact with the flues their entire length before escaping from said chamber 3. into chamber and thus insure more eective heating of the air.
  • rlhe regulated passage for supplying heated air to the surface of the fire-bed by causing it to pass up along the hot sides of the fire-bed is a simple and effective contrivance for promoting better combustion above the fire-bed.
  • the separate primary air chamber surrounding the inner or secondary air-chamber provides larger area of contact-surface in an economical and compact form, and the arrangement, of the smoke-fines in said primary chamber for parting with the heat of the smoke before entering the chimney and at the same time raising the temperature of the incoming cold air in a thorough manner before entering the secondary air-chamber is an efficient means of promoting even and regular currents of the air to be heated, thus preventing unequal and imperfect heating and avoiding obstructive counter-currents inseparable from the introduction of the coldest air directly into one main heating air-chamber of a furnace.
  • the fire-box consisting of two like panshaped parts having ash-port and magazineextension gaps, and smoke outlet or outlets,
  • the fire-box consisting of two like panshaped parts having ash-port and magazineextension gaps, and smoke outlet or outlets, said parts joined and clamped together at the edges and set up with the meeting edges in the vertical central plane, the magazine being above the ash-port and suitably inclined for self or end feeding, and the inclined grate in combination and coincident therewith.
  • the fire-box consisting of two like panshaped parts having ash-port and magazineextension gaps, and smoke outlet or outlets, said parts joined and clamped together at the Y edges and set up with the meeting joint in the vertical central plane, the magazinebeing above the ash-port and suitablyT inclined for self or end feeding; the inclined grate in combination and coincident therewith, and a throat-space at the lower extremity of the grate, opening into the ash-pit.
  • the fire-box consisting of two like panshaped parts having ash-port and magazineextension gaps, and smoke outlet or outlets, said parts joined and clamped together at the edges and set up with the meeting joint in the vertical central plane, the magazine being above the ash-port and suitably inclined for self-feeding; the inclined grate in combination and coincident therewith, a throat-space at the lower extremity of the grate opening into the ash-pit, and the protective plates at the sides of the tire-grate.
  • the nre-box consisting of two like panshaped parts having ash-port and magazineextension gaps, and smoke outlet or outlets,
  • clined self-feeding magazine and fire-grate of the quadrilateral secondary air-chamber, primary air-chamber of like form inclosing three sides of the secondary air-chamber, horizonyprimary air-chamber to the secondary airchamber through the' lower part and opposite sides of the wall of the latter chamber, the hot-air outlets being at the top of the secondary air-chamber.
  • a hot-air self-feeding furnace having the Y quadrilateral primary and second air-heating chambers, the former surrounding three sides of the latter, with cold-air inlet to the primary chamber, and inlets from opposite sides of the primary chamber to the secondaryY chamber and the baffle-plate, arranged to cause the air to traverse the primary chamber from back to front before reaching the linlets to the secondary chamber.

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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)
  • Gasification And Melting Of Waste (AREA)

Description

No. 757,520. I u PATENTED APR. 19, 1904.
E. A. TUTTLRBEGB.
A.. 0. @n K. B. TUTTLE, EXBUUTOBS. v Hoff AIP. HEATING FURN'AGB. APPLICATION FILED SEPT. 26. 1900. BENEWBD JAR-13, 1904. I K0 KODEL. 3 SHEETS-SHEET 1- 1., MM/f; I l i5%/ H//w /X///// v Y@ :s
. /NVENTR No. 757,520. PATENTE!) APR. 19, 1904.
' Y E. A. TUTTLE, DEGD.
A. o. a. n. n. Tu'r'rnz. nxcu'rons. HOT AIR HEATING FURNAGB. l. APrLmL'rIoNQHLED snr'r. sa. 1900. nmmwnn JAN. 1a, 1904. no mmm.. v s sums-SHEET s.
Q6 l i I y 9? /NvEyTo/e JMMAUY WITNESSES y PATENTED APR. 19, 1904. l E. A. TUTTLE, DEUD- A. o. a n. s. Ttr'r'ru., nxnqurons. HOT AIR HEATING FURNAGE.
APVPLIOATION FILED SEPT. 26. 1900. EEHBWED JAN. 13 1904.
3 SHEETS-SHEET 3 H0 IODBL.
Wj ATTY WTNESSES UNITED. STATE-sf :Patented April 19, 1904.
PrrrnNT` OFFICE.
EDWARD A. TUTTLE, OF NEW YORK, Y.; ARTHUR C. TUTTLE AND HERBERT B. TUTTLE EXECUTORS OF SAID EDWARD A. TUTTLE,
DECEASED.
HOT-AIR HEATING-FURNACE.
SPECIFICATION forming part of Letters Patent N 0. 757,520, dated April 1,9, 1904.
Application filed September 26, 1.900. Renewed January 13, 1904. Serial No. 188,923. (No model.)
citizen of the United States of America, and a resident of New York city, county and State of New York, have invented certain new and useful Improvements in Hot- Air Heating'V Furnaces, of which the following is a specification. My invention relates to hot-air heating-fur naces of the kind usually set in brickinclosv ures for causing circulation'of air for heating about the're-box to be heated and being of quadrilateral form; and it comprises improvements in the construction of the fire-box to facilitate simplicity and cheapness of construction, effective and reliable self-feeding .and regular combustion of the fuel, and also effective communicationof the air for transmitting the heat, with the heating-surfaces of the fire-box to be heated, as hereinafter described, reference being made to the accompanying drawings, in whichy Figure 1 represents a central sectional elevation of my improved furnace. Fig. 2 represents a transverse vertical section on line 2 2 of Fig. 1. Fig. 3 represents a horizontal section on line 3 3 of l.
The lire-box A is formed of two equal and.
like cast-metal parts of practically pan shape with lateral extension-gaps c for a self-feed--4 ing magazine, like gaps b for accessto the ash-pit, and holes c for escape of the gases of combustion, said parts adapted to close together at the edges c and be bolted fast through.
lugs cZ, said edges to be planed true, and thus be closed gas-tight. The structure thus produced is set up edgewise-that is, with the joint in the central vertical plane-the magazine being over the ash-port and suitably in-.
clined for gravitation of the coal as the mass below is consumed.
The coal-magazine is provided with a door f for closing while the furnace is working. The ash-port is also provided with a door, as g; but it willhave the usual air-inlet opening andA regulating-valve for controlling the draft. A sloping grate 1' is arranged in line with the bottom ofthe coal-magazine for re- -ceivingthe coal therefrom, said grate terminating a little short of the rear end of the ashpit and also a short distance above the bottom of the ash-pit and leaving an open throat for the settling ofthe ashes, cinders, and clinker down into the ash-pit as the collections are Y raked forward from time to time, said throat being in such proximity to the bottom of the ash-pit that kindling placed under the throat to begin with will choke the throat and obstruct the fall of the coal subsequently charged into the magazine and will occupy the most `favorable relation to the coal for starting the tire, and as the kindling burns away the coal will settle down in contact with the tire for thorough ignition, and for a4 time the lire will be toa considerable extent in and below the throat; but as the ashes accumulate the body of the fire will be higher and the ashes will serve' as a regulator, according as they are raked away from time to time.-
The tire-box is wider than the magazine and the grate, as seen in Figs. Qiand 3, and in the recesses of the sides of the re-box within the magazine side plates le are set up to support refractory material for the protection of the side plates ofthe iire-box from excessive heat, said side plates being inclined correspondingly with the inclination of the grate and reaching from the front plate of the fire-box backward and downward to the backplate, which is preferably formed on an inward incline Z from about the height of the side plates or alittle higher to the top of the ash-pit. As this part of the back plate will usually be protected by ashes and cinders from. excessive heat, refractory lining of it will probably not be needed; but such lining may be applied, if desired.
vThe height of the side plates 7c will bea little more than the depth of the lire-bed. They are flanged, as at on, on the insides to facilitate holding the clay or other lining ofA refractory material, said iianges preferably ranging lengthwise of the plates. These side plates are also flanged or ribbed on the back crosswise, as shown at n, to otiset the platesa little from the side plates of the re-boX and form fine-spaces c in, communication with the air-space under the fire-grate to supply air above the {ire-bed, and dampers p are located above these fines to graduate the supply of' air Vas required, said dampers having their pivot-rods q extending upward through the front of the furnace suitably for manipulating them. These side plates have their ends beveled correspondingly with' their inclinations relatively to the side walls of the lirebox on which they rest, and thus are supported in their positions, being insertible and removable at will without. the manipulation of any fastening devices, except it may be preferred to use a couple of stove-bolts, as g, to prevent them from toppling over.
The grate j is detachably supported on lugs s, projecting inward from the lower ianges m of these side plates,with the lower cross-bar 1f of the grate extended into notches u of said flanges to prevent the grate from slipping downward. By entering the grate through the magazine engaging the projecting ends of bar with the notches u and dropping the up- 'per end of the grate onto its bearing-lugs s the grate will be readily placed in position,
and it is obvious that it may be as readily re-v moved by the reverse of these movements. The lining of the side plates may have to be notched a little at the notches u ofthe lower flanges m to facilitate the engagement of the said projecting ends of bar with saidl notches u.
The lire-box isp'laced in a brick inclosure Q), in which it is supported on abutments w, and in the front Wall where the ash-port and magazine project through it with intervening space for causing effective contact of the air for transmitting the heat with the plates of the tire-box for being heated. The air enters to this space hereinafter called the secondary air-chamber, through inlets y of the inclosure o and is conducted away from the top, as usual, through conductors e. Another brick inclosure 2 surrounds three sides of inclosure 'u and includes an air-space 3, hereinafter called the primary air-chamber, into which the air for heating is received at 4, wherefrom it passes along the walls of inclosure o to the inlet-passages y and is heated thereby to a considerable extent before enter'- ingthe hot spaces of the secondary air-chamber m next to the fire-'box The air in primary chamber 3 is also furtherheated by flues 5, located therein and receiving the hot products from the {ire-box through pipes 6, communicating with the fire-box at e and passing through walls o. The lues 5 discharge through branch pipes 7 into the smoke-pipe 8, which connects with the chimney, as usual, for discharge into the air, said pipe 8 being located in the cold-'air inlet 4 for giving up as much as possiblefof the heat of the waste products before escaping.
The iiues are made wide and shallow, as represented in Fig. 2, for affording large area of surface exposure proportionately to the volume capacity for economy in heating the air by contact, which is known to be the essential way, as it does not absorb radiant heat.
The smoke-fines are. arranged horizontally along the sides of the lire-box in primary airchamber 3, and the discharge-pipe enters the chimney at about the same level, and the incoming cold air is carried along in the opposite direction, iirst coming in contact with the outgoing end of the smoke-pipe.
Instead of a smokepipe 6 at each side of the fire-box discharging into the chimney at the back the pipe 6 of one side may be omitted, and a single flue connecting with the one pipe may be extended around the three sides of the primary chamber into the chimney located at the-side of the re-boxopposite the remaining pipe 6.
BafHe-plates 9 in chamber 3 under iiues 5 cause the incomingair to flow along and in contact with the flues their entire length before escaping from said chamber 3. into chamber and thus insure more eective heating of the air.
Some of the advantages of my improved furnace may be stated as follows:
The inclined fire-bed and coal-magazine at the upper end of the bed allow a'constant selffeed of the fuel into the end of the ire-box,
never overcharging and choking the flre, but always maintaining a lively and even lire and constant maximum radiation of heat to the plates of the {ire-box. The livelier and more uniform fire thus affords more heat from a smaller area of fire-bed, and more heat is obtained from the coal consumed, because of the more perfect combustion of the4 gases evolved from the coal, Va large proportion of which it is known goes to waste whenever the fire is choked and combustion checked by charging the air with fresh supplies of coal from time to time.
rlhe regulated passage for supplying heated air to the surface of the fire-bed by causing it to pass up along the hot sides of the fire-bed is a simple and effective contrivance for promoting better combustion above the fire-bed.
The separate primary air chamber surrounding the inner or secondary air-chamber provides larger area of contact-surface in an economical and compact form, and the arrangement, of the smoke-fines in said primary chamber for parting with the heat of the smoke before entering the chimney and at the same time raising the temperature of the incoming cold air in a thorough manner before entering the secondary air-chamber is an efficient means of promoting even and regular currents of the air to be heated, thus preventing unequal and imperfect heating and avoiding obstructive counter-currents inseparable from the introduction of the coldest air directly into one main heating air-chamber of a furnace.
As the air must be heated by contact, it is IOO important that'i ak large of 'contact-sur- `,facetbethrought tojbea'r to raise the temperatureffiom, slay, zero orthereabout Vto 700 Fahrenheit, which is ,frequently the difference between 'the outside "air and the required ytemperature of one room.
with limited heating-sunsetimpressum' bed, fails to give reasonable returns of heat"- for its large consumption of fuel.
What I claim as my invention isl. The fire-box consisting of two like panshaped parts having ash-port and magazineextension gaps, and smoke outlet or outlets,
said parts joined and clamped together at the edges and set up with the meeting joint in the vertical center plane, the magazine being above the ash-port and suitably inclined for self-feeding the coal.
2. The fire-box consisting of two like panshaped parts having ash-port and magazineextension gaps, and smoke outlet or outlets, said parts joined and clamped together at the edges and set up with the meeting edges in the vertical central plane, the magazine being above the ash-port and suitably inclined for self or end feeding, and the inclined grate in combination and coincident therewith.
3. The fire-box consisting of two like panshaped parts having ash-port and magazineextension gaps, and smoke outlet or outlets, said parts joined and clamped together at the Y edges and set up with the meeting joint in the vertical central plane, the magazinebeing above the ash-port and suitablyT inclined for self or end feeding; the inclined grate in combination and coincident therewith, and a throat-space at the lower extremity of the grate, opening into the ash-pit.
4:. The fire-box consisting of two like panshaped parts having ash-port and magazineextension gaps, and smoke outlet or outlets, said parts joined and clamped together at the edges and set up with the meeting joint in the vertical central plane, the magazine being above the ash-port and suitably inclined for self-feeding; the inclined grate in combination and coincident therewith, a throat-space at the lower extremity of the grate opening into the ash-pit, and the protective plates at the sides of the tire-grate.
5. The nre-box consisting of two like panshaped parts having ash-port and magazineextension gaps, and smoke outlet or outlets,
said parts joined and clamped together at the edges, and set up with the meeting joint in the central vertical plane, the magazine being above they ash-'port'and'siiitably inclined for Vself-'feeding kthe inclined grate in combination and coincident therewith, a throat-space at the lower extremity of the grate opening into the ash-pit` the composite protective plates at the sidesof the iire-grateysaid plate 'having thel 'ribbed backbfsetting it fromithe' fire-box 'platesand forming'iair-ducts supplying air over the fire-'bed and valves controlling said ducts.
6. The combination with the fire-box, in-
clined self-feeding magazine and fire-grate, of the quadrilateral secondary air-chamber, primary air-chamber of like form inclosing three sides of the secondary air-chamber, horizonyprimary air-chamber to the secondary airchamber through the' lower part and opposite sides of the wall of the latter chamber, the hot-air outlets being at the top of the secondary air-chamber.
7 The combination with the lire-box, inclined self-feeding magazine and fire-grate, of the quadrilateral secondary air-chamber, primary .air-chamber of like form surrounding three sides of the secondary air chamber, horizontal smoke-fines located in the three divisions of said chamber, and connected with the fire-box through the inclosure .of the secondary air-chamber, inlet for cold air to the primary air-chamber, discharge-pipe of the smoke-fines extended through said cold-air inlet, and air-inlets from the primary airchamber to the secondary air-chamber through the opposite sides of the wall of said latter chamber at the base.
8. The combination with the inclined rebed and magazine, of vertical air-passages behind and intermediate of the side walls of the fire-bed, and the shell of the fire-box from the ash-pit to the surface of the fire-bed, and valves lying over the issues of said passages at their upper ends, said valves having their pivot rods extending upward through the front wall ot' the furnace, said passages being formed in said side walls.
9. A hot-air self-feeding furnace having the Y quadrilateral primary and second air-heating chambers, the former surrounding three sides of the latter, with cold-air inlet to the primary chamber, and inlets from opposite sides of the primary chamber to the secondaryY chamber and the baffle-plate, arranged to cause the air to traverse the primary chamber from back to front before reaching the linlets to the secondary chamber.
IOO
ary air-chamber, inlet for cold air to the pri- 'lues before reaching the inlets from the tpriimary chamber, discharge-pipe of the smokemary chamber to the secondary chamber- IO lues extended through said cold-air inlet, air- Signed at New York city this 7 th d'ay of inlets from the primary air-chamber to the July, 1900.
5 secondary air-chamber through the Wall of EDWARD A. TUTTLE.
said latter chamber at the base, and the baii'e- Witnesses: plates in the primary chamber causing the C. SEDGWICK,
cold air to traverse the length of the smoke- J. M. HOWARD.
US18892300A 1900-09-26 1900-09-26 Hot-air heating-furnace. Expired - Lifetime US757520A (en)

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