US2573364A - Air-heating furnace with liquid heat transfer means - Google Patents

Air-heating furnace with liquid heat transfer means Download PDF

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US2573364A
US2573364A US74670A US7467049A US2573364A US 2573364 A US2573364 A US 2573364A US 74670 A US74670 A US 74670A US 7467049 A US7467049 A US 7467049A US 2573364 A US2573364 A US 2573364A
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casing
air
tubes
heater
sections
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US74670A
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John E Scharff
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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
    • F24H6/00Combined water and air heaters

Definitions

  • My invention is an improved heating apparatus, particularly a heater of large capacity in comparison with its size; and adapted to circulate warmed air for indoor spaces, such as oices, apartments and dwellings.
  • An important object of my invention is to provide a heater of unitary construction and design, simple and relatively inexpensive to produce and assemble, having a high operating efficiency, and easy to inspect and repair.
  • Another object is to provide a heater wherein the heating medium, such as air, is warmed in successive stages; thus utilizing to the greatest degree the fuel consumed in the process.
  • the heating medium such as air
  • Figure l is a vertical sectional view through a heating apparatus according to this invention.
  • Figure 2 is a section through a part of the apparatus, showing a modification seen from one side.
  • Figure 3 is a View of the same parts seen from one end;
  • FIGS 4, 5 and ⁇ 6 show details of the heater.
  • the housing has an interior partition 4, dividing the unit into two compartments 5 and 6; the air entering the former; and, after being heated to the required degree, being discharged from the latter.
  • the other chamber 5 contains a blower fan or impeller 9, which effects the transfer of the air from the one chamber to the other; this fan causing a ow of air from the inlet chamber 5 to the chamber 5 through a suitable opening in the partition 4.
  • a burner is shown at II, with a nozzle I2 for liquid or gaseous fuel entering the space I0.
  • I can use any heating unit that is the equivalent of that disclosed herein.
  • Each tier of ,tubes 8 includes several tubes disposed side by side, the tubes of one tier being staggered with respect to the tubes in the tiers immediately above and below it.
  • the casing I is closed at the sides, bottom and top, and the products of combustion are passed through a smoke flue I3 connected to the casing 'I at the top and passing through the partition 4 and across the housing I and out of the latter.
  • This flue spans the chamber 5 just below the inlet 2.
  • a heating member or radiator I4 consisting of a number of pipes connected to the uppermost tubes 8.
  • To this radiator is coupled an outlet pipe I5 leading to a hot water heater I'I; and beyond this heater I'I is a pipe leading to pump I8, and then to a pipe or conduit I 9 coupled to the lowermost tubes 8.
  • the fan 9 and the pump I8 are both driven by an electric motor 2U, which is connected to the fan and pump respectively by belts ZI and 22.
  • the fuel such as oil or gas consumed in the space I0
  • heats the water in the tubes 8 and the burnt gases flow out through the ilue I3.
  • Hot water from the uppermost tubes 8 ows through the radiator I4.
  • the incoming air comes into contact with the radiator I4 and its temperature is raised as a result.
  • Reaching the flue I3, which acts as another heating member the air now has its temperature further increased; and the warmed air next enters the fan casing and is forced through an opening in the partition 4 into the compartment 6.
  • it absorbs more heat from the walls of the casing l; and has its maximum temperature when the air passes out through the opening 3.
  • This outlet may be connected to air flues to lead the air to points where heating is needed, or the heater may deliver the air directly into the space containing the housing I.
  • the air is thus heated in several stages as it flows through the heater, and the operation is very ecent.
  • the maximum effect is obtained from the fuel burnt in the chamber I0.
  • the fan of course delivers through the lowest part of the partition.
  • the pipe 25 connects the header of the uppermost tubes 3 to the member I4.
  • the radiator is connected to an expansion tank 26, and has a vent cock 21 at the top.
  • a coil IE that is supplied with water through an inlet pipe 28; and the contents of this coil i6 are discharged as hot water for domestic use from an outlet pipe 32 coupled to the coil I6 at the top.
  • a feed pipe 29 having a relief feed and relief valve.
  • a three Way cock 30 is used to cut off the pipe 28V so that the coil l5 can be back-flushed and cleaned of sediment.
  • the pipe 29 has a drain cock 3
  • an air filter 33 is in the inlet opening 2.
  • the heater sections made up of the tubes 8 and the headers 23 are of steel, and are joined by Welding.
  • the heater members have the form of cast iron sections 34, and each includes headers 35 joined by water pipes 35.
  • the sections are joined by coupling or push nipples 3l in such a way that the water in the sections flows in zigzag fashion as before through them from bottom to top.
  • the width and depth of the casing 'i are as indicated in Figures 2 and 4, the -depth being somewhat greater than the width. All of the sections 34 have the same length as shown in Figure 2, but some may be narrower, as indicated on Figure 3.
  • the top and bottom sections 34 may have seven tubes each, for example, the middle ⁇ section six; and the sections adjacent top and bottom sections may also have six tubes each. Between the last named sections and the central section, the two remaining sections have five tubes each, such a section being indicated on Figure 6.
  • the tubes of the successive sections are staggered as before, with respect Vto the tubes above and below them. This construction is just as eflicient and advantageous as the first design above described.
  • the headers are spaced from the casing l, and the heating medium therein, passing into the radiator I4, acts only on the air entering the compartment 5 to raise its temperature.
  • the burner i2 also heats the walls of the casing 1, and the air impelled by the blower into the compartment 6 is forced into contact with the casing 'l and its temperature is increased again.
  • This construction is very efficient. With one actual installation for example, the incoming air had a temperature of 60 degrees F. at the inlet, and this was raised to 127 degrees by the radiator I4. At the outlet 3 the air after contact with the. casing 1, had a temperature of over 160 degrees.
  • the blower 9 is not operating the casing l acts to prevent loss of heat from the pipes 8 and headers 23.
  • the radiator I4 also comprises headers joined by pipes in two layers, and these pipes may carry outside iins 38.
  • Heating apparatus comprising a housing having a vertical partition therein dividing it into two compartments, one having an outlet at the top and the other an inlet at the top, a casing containing heater sections including hollow headers spaced from the walls of the casing and conduits connecting said headers in the one compartment, a burner located within the casing and adjacent the sections for heating the same, a hollow heater member comprising conduits in the other compartment adjacent the inlet thereof and conduit means connecting the heater member to said sections, a smoke flue connected to the top of the casing and extending through the other compartment at the top thereof adjacent said heater member to the outside of the housing, the partition having an opening adjacent burner end of the casing, an impeller mounted to discharge through the opening in said partition, and a return line connecting the heater member to said sections adjacent said burner end of said casing, a pump in said return line, and a motor in the housing connected -to the impeller and the pump.
  • Heating apparatus comprising a housing having a partition therein dividing it into two compartments, one having an outlet and the other an inlet, a casing containing heater sections including hollow headers spaced from the walls of the casing and conduits connecting said headers in the one compartment, a burner 1ocated within the casing and adjacent the sections for heating the same, a hollow heater member comprising conduits in the other compartment adjacent the inlet thereof and conduit means connecting the heater member to said sections, a smoke flue connected toy the casing and extending through the other compartment thereof adjacent said heater member to the outside of the housing, the partition having an opening adjacent the burner end of said casing, an impeller mounted to discharge through the opening in said partition, and a return line connecting the heater member to said sections adjacent said burner end of .said casing, a pump in said return line, and a moto-r in the housing connected to the impeller and the pump. f

Description

J. E. SCHARFF Filed Feb. 4, 1949 il!! Iffflll/ l INVENTOR BYJohn E. Schorff ZM f f. w( ATTORNEY Oct. 30, 1951 AIR-HEATING EURNACE WITH LIQUID HEAT TRANSFER MEANS FIGA- Patented Oct. 30, 1 951 AIR-HEATING FURNACE WITH LIQUID HEAT TRANSFER MEANS John E. Scharff, New Rochelle, N. Y.
Application February 4, 1949, Serial No. 74,670
2 Claims.
My invention is an improved heating apparatus, particularly a heater of large capacity in comparison with its size; and adapted to circulate warmed air for indoor spaces, such as oices, apartments and dwellings.
An important object of my invention is to provide a heater of unitary construction and design, simple and relatively inexpensive to produce and assemble, having a high operating efficiency, and easy to inspect and repair.
Another object is to provide a heater wherein the heating medium, such as air, is warmed in successive stages; thus utilizing to the greatest degree the fuel consumed in the process.
The nature' and advantages of the invention are fully described herein, and the drawings illustrate one or more practical embodiments oi the heater. But this disclosure is explanatory only, and variations in structural details can be adopted without deviation from the general plan that characterizes the improvement.
On the drawings;
Figure l is a vertical sectional view through a heating apparatus according to this invention.
Figure 2 is a section through a part of the apparatus, showing a modification seen from one side.
Figure 3 is a View of the same parts seen from one end; and
Figures 4, 5 and`6 show details of the heater.
top of the housing, though of course they may l be placed elsewhere. The housing has an interior partition 4, dividing the unit into two compartments 5 and 6; the air entering the former; and, after being heated to the required degree, being discharged from the latter. Within the outlet chamber 6 is the casing 'l of a heater unit containing water tubes or pipes 8, arranged in zigzagging tiers between the Vbottom and the top of the casing l. The other chamber 5 contains a blower fan or impeller 9, which effects the transfer of the air from the one chamber to the other; this fan causing a ow of air from the inlet chamber 5 to the chamber 5 through a suitable opening in the partition 4. In the casing I is a combustion chamber I@ at the lower end, the lower portion of the walls of the casing 'I having a suitable fire-resistant lining. A burner is shown at II, with a nozzle I2 for liquid or gaseous fuel entering the space I0. I, of course, can use any heating unit that is the equivalent of that disclosed herein.
Each tier of ,tubes 8 includes several tubes disposed side by side, the tubes of one tier being staggered with respect to the tubes in the tiers immediately above and below it. The casing I is closed at the sides, bottom and top, and the products of combustion are passed through a smoke flue I3 connected to the casing 'I at the top and passing through the partition 4 and across the housing I and out of the latter. This flue spans the chamber 5 just below the inlet 2. Between this flue and the inlet 2 is a heating member or radiator I4, consisting of a number of pipes connected to the uppermost tubes 8. To this radiator is coupled an outlet pipe I5 leading to a hot water heater I'I; and beyond this heater I'I is a pipe leading to pump I8, and then to a pipe or conduit I 9 coupled to the lowermost tubes 8.
The fan 9 and the pump I8 are both driven by an electric motor 2U, which is connected to the fan and pump respectively by belts ZI and 22.
In operation, the fuel, such as oil or gas consumed in the space I0, heats the water in the tubes 8, and the burnt gases flow out through the ilue I3. Hot water from the uppermost tubes 8 ows through the radiator I4. The incoming air comes into contact with the radiator I4 and its temperature is raised as a result. Reaching the flue I3, which acts as another heating member, the air now has its temperature further increased; and the warmed air next enters the fan casing and is forced through an opening in the partition 4 into the compartment 6. Here it absorbs more heat from the walls of the casing l; and has its maximum temperature when the air passes out through the opening 3. This outlet may be connected to air flues to lead the air to points where heating is needed, or the heater may deliver the air directly into the space containing the housing I. The air is thus heated in several stages as it flows through the heater, and the operation is very ecent. The maximum effect is obtained from the fuel burnt in the chamber I0. The fan of course delivers through the lowest part of the partition.
Within the casing l, and ailixed to opposite walls thereof are horizontal supports in the form of brackets or angle irons 24 for headers 23 connected to both ends of the tubes 8 of each tier thereof. From the header coupled to the pipe I9, the lower most tubes cross at an incline to the lowest header on the opposite wall ofthe casing;
being connected to this header adjacent the bottom. Other tubes of this header are connected thereto near the top and lead across the casing at an upward incline to the lower part of the next header, just above the first. As indicated on Figure 4, the tubes of one tier are staggered with respect to the tubes above and below; so that some of the tiers have one more tube than the rest. Thus the hot gases of combustion which flow upward in the casing 7, make contact with an aggregate heating surface of the maximum extent, and the water in thetubes 8 is quickly heated to the required degree. The pipe 25 connects the header of the uppermost tubes 3 to the member I4.
The radiator is is connected to an expansion tank 26, and has a vent cock 21 at the top. In the tank I1 is a coil IE, that is supplied with water through an inlet pipe 28; and the contents of this coil i6 are discharged as hot water for domestic use from an outlet pipe 32 coupled to the coil I6 at the top. To the pipe I9 is joined a feed pipe 29 having a relief feed and relief valve. A three Way cock 30 is used to cut off the pipe 28V so that the coil l5 can be back-flushed and cleaned of sediment. The pipe 29 has a drain cock 3|. Preferably an air filter 33 is in the inlet opening 2.
In Figures 1 and 4 the heater sections made up of the tubes 8 and the headers 23 are of steel, and are joined by Welding. On Figures 2 and 3, the heater members have the form of cast iron sections 34, and each includes headers 35 joined by water pipes 35. The sections are joined by coupling or push nipples 3l in such a way that the water in the sections flows in zigzag fashion as before through them from bottom to top. The width and depth of the casing 'i are as indicated in Figures 2 and 4, the -depth being somewhat greater than the width. All of the sections 34 have the same length as shown in Figure 2, but some may be narrower, as indicated on Figure 3. The top and bottom sections 34 may have seven tubes each, for example, the middle `section six; and the sections adjacent top and bottom sections may also have six tubes each. Between the last named sections and the central section, the two remaining sections have five tubes each, such a section being indicated on Figure 6. The tubes of the successive sections are staggered as before, with respect Vto the tubes above and below them. This construction is just as eflicient and advantageous as the first design above described. The headers are spaced from the casing l, and the heating medium therein, passing into the radiator I4, acts only on the air entering the compartment 5 to raise its temperature. The burner i2 also heats the walls of the casing 1, and the air impelled by the blower into the compartment 6 is forced into contact with the casing 'l and its temperature is increased again. This construction is very efficient. With one actual installation for example, the incoming air had a temperature of 60 degrees F. at the inlet, and this was raised to 127 degrees by the radiator I4. At the outlet 3 the air after contact with the. casing 1, had a temperature of over 160 degrees. When the blower 9 is not operating the casing l acts to prevent loss of heat from the pipes 8 and headers 23.
The radiator I4 also comprises headers joined by pipes in two layers, and these pipes may carry outside iins 38.
Other appliances than oil or gas burners for heating may be employed.
Having described my invention, what I believe to be new is:
1. Heating apparatus comprising a housing having a vertical partition therein dividing it into two compartments, one having an outlet at the top and the other an inlet at the top, a casing containing heater sections including hollow headers spaced from the walls of the casing and conduits connecting said headers in the one compartment, a burner located within the casing and adjacent the sections for heating the same, a hollow heater member comprising conduits in the other compartment adjacent the inlet thereof and conduit means connecting the heater member to said sections, a smoke flue connected to the top of the casing and extending through the other compartment at the top thereof adjacent said heater member to the outside of the housing, the partition having an opening adjacent burner end of the casing, an impeller mounted to discharge through the opening in said partition, and a return line connecting the heater member to said sections adjacent said burner end of said casing, a pump in said return line, and a motor in the housing connected -to the impeller and the pump.
2. Heating apparatus comprising a housing having a partition therein dividing it into two compartments, one having an outlet and the other an inlet, a casing containing heater sections including hollow headers spaced from the walls of the casing and conduits connecting said headers in the one compartment, a burner 1ocated within the casing and adjacent the sections for heating the same, a hollow heater member comprising conduits in the other compartment adjacent the inlet thereof and conduit means connecting the heater member to said sections, a smoke flue connected toy the casing and extending through the other compartment thereof adjacent said heater member to the outside of the housing, the partition having an opening adjacent the burner end of said casing, an impeller mounted to discharge through the opening in said partition, and a return line connecting the heater member to said sections adjacent said burner end of .said casing, a pump in said return line, and a moto-r in the housing connected to the impeller and the pump. f
JOHN E. SCHARFE.
REFERENCES CITED The following references are of record in the rile of this patent:
UNITED STATES PATENTS Number Name Date 208,822 Hulings Oct. 8, 1878 1,846,292 Whiteley Feb. 23, 1932 2,190,998 Summers Feb. 20, 1940 2,212,222 Aust-in Aug. 20, 1940 2,225,181 Powers Dec. 17, 1940 2,249,554 Daly July 15, 1941 2,269,055 Gower Jan. 6, 1942 2,363,742 Norton Nov. 28,` 1944 FOREIGN PATENTS Number Country Date 401,743 Germany Sept. 8, 1924
US74670A 1949-02-04 1949-02-04 Air-heating furnace with liquid heat transfer means Expired - Lifetime US2573364A (en)

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Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2827893A (en) * 1955-01-28 1958-03-25 Andrew A Ribaudo Furnace system for heating air and water
US3033192A (en) * 1959-07-18 1962-05-08 Ventilatorverken Ab Air and water heating devices
US3236226A (en) * 1963-05-28 1966-02-22 Thermodynamics Combined air and water heaters
US3742929A (en) * 1971-11-26 1973-07-03 R Dupler Hot water and hot air heating system
US4147301A (en) * 1977-04-13 1979-04-03 Halma Wayne G Heating system
US4310746A (en) * 1976-07-28 1982-01-12 Elkern Kenneth E Electric fluid heating apparatus
FR2568355A1 (en) * 1984-07-25 1986-01-31 Gaz De France METHOD OF HEATING ANY BUILDING OR LOCAL BUILDING AND APPARATUS COMPRISING THE APPLICATION OF SAID METHOD
US5046478A (en) * 1990-11-30 1991-09-10 Raytheon Company Recuperative furnace system for space air and domestic hot water
US6109339A (en) * 1996-07-15 2000-08-29 First Company, Inc. Heating system
US20080264490A1 (en) * 2007-04-24 2008-10-30 Rinnai America Corporation, A Corporation Of Georgia Methods and apparatus for heating air with hot water

Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US208822A (en) * 1878-10-08 Improvement in heating apparatus for buildings
DE401743C (en) * 1924-09-08 Bernhard Schulze Device for heating air in a hot water boiler
US1846292A (en) * 1928-03-15 1932-02-23 Frank A Whiteley Hot air heating plant
US2190998A (en) * 1938-06-22 1940-02-20 William S Somers Air conditioning apparatus
US2212222A (en) * 1938-06-13 1940-08-20 Florence G Austin Combination water and air conditioning apparatus
US2225181A (en) * 1937-03-05 1940-12-17 Powers Donald Hess Heating and air conditioning unit
US2249554A (en) * 1939-02-24 1941-07-15 Francis R Daly All-weather hot air furnace
US2269055A (en) * 1939-08-25 1942-01-06 Gower Thomas Charles Split heating system
US2363742A (en) * 1941-02-10 1944-11-28 John A Norton Furnace

Patent Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US208822A (en) * 1878-10-08 Improvement in heating apparatus for buildings
DE401743C (en) * 1924-09-08 Bernhard Schulze Device for heating air in a hot water boiler
US1846292A (en) * 1928-03-15 1932-02-23 Frank A Whiteley Hot air heating plant
US2225181A (en) * 1937-03-05 1940-12-17 Powers Donald Hess Heating and air conditioning unit
US2212222A (en) * 1938-06-13 1940-08-20 Florence G Austin Combination water and air conditioning apparatus
US2190998A (en) * 1938-06-22 1940-02-20 William S Somers Air conditioning apparatus
US2249554A (en) * 1939-02-24 1941-07-15 Francis R Daly All-weather hot air furnace
US2269055A (en) * 1939-08-25 1942-01-06 Gower Thomas Charles Split heating system
US2363742A (en) * 1941-02-10 1944-11-28 John A Norton Furnace

Cited By (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2827893A (en) * 1955-01-28 1958-03-25 Andrew A Ribaudo Furnace system for heating air and water
US3033192A (en) * 1959-07-18 1962-05-08 Ventilatorverken Ab Air and water heating devices
US3236226A (en) * 1963-05-28 1966-02-22 Thermodynamics Combined air and water heaters
US3742929A (en) * 1971-11-26 1973-07-03 R Dupler Hot water and hot air heating system
US4310746A (en) * 1976-07-28 1982-01-12 Elkern Kenneth E Electric fluid heating apparatus
US4147301A (en) * 1977-04-13 1979-04-03 Halma Wayne G Heating system
FR2568355A1 (en) * 1984-07-25 1986-01-31 Gaz De France METHOD OF HEATING ANY BUILDING OR LOCAL BUILDING AND APPARATUS COMPRISING THE APPLICATION OF SAID METHOD
EP0172086A1 (en) * 1984-07-25 1986-02-19 Gaz De France Apparatus for heating a building or a room
US4638943A (en) * 1984-07-25 1987-01-27 Gaz De France Method of heating any building or room and apparatus for carrying out the said method
US5046478A (en) * 1990-11-30 1991-09-10 Raytheon Company Recuperative furnace system for space air and domestic hot water
US6109339A (en) * 1996-07-15 2000-08-29 First Company, Inc. Heating system
US20080264490A1 (en) * 2007-04-24 2008-10-30 Rinnai America Corporation, A Corporation Of Georgia Methods and apparatus for heating air with hot water
US8353463B2 (en) * 2007-04-24 2013-01-15 Rinnai America Corporation Methods and apparatus for heating air with hot water
US8662404B2 (en) 2007-04-24 2014-03-04 Rinnai America Corporation Methods and apparatus for heating air with hot water
US9810449B2 (en) 2007-04-24 2017-11-07 Rinnai America Corporation Methods and apparatus for heating air with hot water

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