US1193245A - Cobbab jdkessleb - Google Patents

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US1193245A
US1193245A US1193245DA US1193245A US 1193245 A US1193245 A US 1193245A US 1193245D A US1193245D A US 1193245DA US 1193245 A US1193245 A US 1193245A
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oven
chamber
cooling
air
conduits
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    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27FURNACES; KILNS; OVENS; RETORTS
    • F27BFURNACES, KILNS, OVENS, OR RETORTS IN GENERAL; OPEN SINTERING OR LIKE APPARATUS
    • F27B9/00Furnaces through which the charge is moved mechanically, e.g. of tunnel type; Similar furnaces in which the charge moves by gravity
    • F27B9/06Furnaces through which the charge is moved mechanically, e.g. of tunnel type; Similar furnaces in which the charge moves by gravity heated without contact between combustion gases and charge; electrically heated
    • F27B9/08Furnaces through which the charge is moved mechanically, e.g. of tunnel type; Similar furnaces in which the charge moves by gravity heated without contact between combustion gases and charge; electrically heated heated through chamber walls
    • F27B9/082Muffle furnaces

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  • This invention relates to ovens wherein, for the purpose of enabling the heat resulting from the combustion of gaseous or other fuel, to be economically,-uniformly and effectively utilized,'the'heating chamber of the oven is provided with one or more longitudinally arranged combustion chambers so arranged therein that when the'oven is in use,
  • air will be heated and caused to'ascend between the outer side of the combustion chamber, or each combustion chamber, and the adjacent, side wall of the heating chamber to the top of the oven, then descend among the goods to be heated in the oven and afterward pass under the combustion chamber to the outer side thereofto be reheated and again circulated.
  • air is sometimes allowed to flow through a portion of the oven and come in contact with the heated goods while they are in the cooling zone of .the oven and itself become heated, such heated airbeing admitted to the combustion chamber or chambers for effecting combustion therein.
  • While such an oven is suitable for heating and treatingnot only pottery and the like but also ores and other materials or articles that require or may be subjected to the oXidizing action of air on their passage along the cooling zone it is not suitable for use in cases where it is desired to subject ores or other materials or articlesthereinafter referred to as materials) to the action of a reducing, neutral, acid or alkaline atmosphere, or for heating materlals, for example sulfids or carbonates, that cause the production or evolution of gases, not suitable for admission to the combustion chamber or chambers, or, it may be, to the external atmosphere.
  • the present invention has for its obect to enable an oven of the kind mentioned to be kept throughout its length, and including itscooling zone, entirely independent so far as its gaseous contents are concerned, from the combustion chamber or chambers and from the air supply thereto, so that the oven can be used for heating materials in an atmosphere of any desired character,for
  • the coolingzone of the oven is provided with two or more tubes or conduits, or sets of tubes or conduits (hereinafter referredto as conduits),
  • the ends of the oven are or may be normally closed so as to confine the atmosphere therein and the oven wall may be provided at suitable points with holes or passages for the inlet, or inlet and outlet, of the gaseousfluid to be used in the oven except, it may be, in the case where air is to be used, unless the air is to be used under pressure.
  • the arrangement of conduits in the cooling zone ofthe oven may also be used for heating combustible gas simultaneously with the air, the air and combustible gas being brought into contact at the end of the cooling-zone, after they have acquired to occur when fire clay or analogous material is used for making the conduits.
  • conduits for eXample those for supplying heated air and gas to the combustion chamber or chambers, may be arranged one Within the other.
  • the heated material can be effectually cooled by air that is prevented from coming into contact with and being contaminated by such material
  • the air so heated being available for various useful purposes.
  • Fig. 3 is a horizontal section
  • Fig. 4 a cross section-on the line C C of Fig. 3, showing,
  • Fig. 5 shows in cross section two conduits arranged one within the other.
  • Fig. 6 is a cross section on the line D D of Fig. 1.
  • each conduit 0 is connected to one end of a junction piece f the other end of which is connected to the adjacent end of the corresponding combustion chamber h which is the conduits 6 can be led to any desired place and utilized or not as desired.
  • conduits d, e are supported above the floor m at each side of the passage way 0 and spaced apart and from the walls of the cooling zone of the oven so that the air or other gaseous medium heated in the cooling zone by the hot goods or materials therein can. circulate or pass freely between and around such conduits and: impart its heat thereto so that the goods or inaterialwill be cooled and the heat thereof utilized.
  • the outer ends of the conduits d. are, or may be fitted with valves'n for controlling. the amount of air supplied to the combustion chambers h.
  • the passage may be a suction passage connected to a fan for causing air to flow at any desired rate through the conduits e to suit requirement.
  • the conduits d and a may conveniently be made of fireclay or other refractory material. They may however be of metal and of circular or other sha'pe and be of smaller cross. section and more numerous than those shown.
  • Fig. 5 shows how one of the air conduits d of Figs. 1 and 3 can be provided with an internal conduit 0 through which combustible gas can be supplied from any convenient source to the corresponding junction piece f to be burnt therein by the aid of the air supplied through the said air conduit.
  • the conduit 0 can be supported within the conduit (Z in any convenient manner.
  • the oven is or may be closed at its ends preferably by double doors or air locks 72 for the purpose of effectively protecting the contents of the oven from the external atmosphere.
  • the oven may be provided with any suit-' able arrangement of inlets for admitting thereto any desired gaseous medium for producing in the oven an atmosphere of any desired character, as for example reducing, neutral, acid or alkaline.
  • any desired gaseous medium for producing in the oven an atmosphere of any desired character, as for example reducing, neutral, acid or alkaline.
  • an inlet pipe 1' having exit apertures '2" opening into the oven.
  • a special outlet for gaseous medium from the oven may also if desired be provided in one or both of the ends or end portions of the oven, as.shown for example at s, or at other desired point or points. Sometimes, however, no special outlet will be necessary.
  • the arrows 1 indicate the course of the air through the conduits (Z to the junction pieces 7 and combustion chambers h; the arrow 2 the direction of the combustible gas admitted to the junction pieces f wherein such gas is mixed with the heated air supplied through the conduits (l; the arrows 3 the courseof the products of combustion from the combustion chambers; the arrows 4 the course of the air to and from the conduits e; and the arrow 5 the direction of any gaseous medium admitted to the interior. of the oven through the supply pipe 1" and inlet apertures 1*.
  • the combustion chambers It are connected at their outlet ends through apertures t toa pipe 11. connected to a chimney v or other suitable exhausting device that will cause the products of combustion to flow in the direction of-the arrows 3.
  • the goods or material to be heated travel through the oven in a direction from right to left in i Fig. 1 so that they are first heated and then cooled.
  • An oven comprising a heating chamber, a cooling, chamber forming a. continuation thereof, a combustion chamber, supported in the heating chamber so that gaseous fluid can circulate around it and out of communication with the heating and cooling chambers, a cooling conduit supported in the cooling chamber and connected to the combustion chamber and means for introducing fuel in a. fluid condition to the combustion chamber.
  • an oven comprising a heating chamher and a cooling chamber forming a continuation (thereof, a combustion chamber and a cooling conduit arranged respectively in said heating andcooling chambers and *in alin ement with each other and ajunction piece connecting said chamber and conduit together.
  • An oven comprising a heating zone and a cooling zone, a combustion chamber supported at one side of the heating zone, above the floor and at a, distance from the adjacent side of the oven and having its interior out of communication with the interior of the oven,an air conduit also out of communication with the interior of the oven but in communication with the interior ofthe combustion chamber and extending freely through the cooling zone-at one side thereof and means for supplying combustible as to the air that has passed througl the air conduit.
  • an oven comprising a heating cham her and a cooling chamber forming a con tinuation thereof, a combustion chamber and a cooling conduit arranged respectively insaid heating and cooling chambers and the cooling chamber being in communication with the external atmosphere at one end and with the combustion chamber at the other end and means for throttling the entrance of air tothe cooling conduit.
  • an oven comprising aheating chamher and a cooling chamber forming a continuation thereof, a oambustion chamber arranged in the hearth g chamber, a cooling conduit arranged in said cooling chamber and through which air can pass, a junction piece connecting said combustion chamber and cooling conduit and having an inlet for a fuel in a fluid condition and means for throttling the entrance of air to the cooling conduit.
  • an oven comprising a heating chamher and a cooling chamber in alinement with each other, a number of cooling conduits supported longitudinally within the cooling chamber with their inlet ends remote from the heating chamber and their outlet ends toward the heating chamber and through which cooling fluid can flow and become gradually heated.
  • an oven comprising a heating chamber and a cooling chamber arranged in alinement with each other and through which goods can pass successively, a combustion chamber arranged longitudinally in the heating chamber and out of communication with both chambers, and two air conduits supported within and-extending 10W longitudinally of the cooling chamber and each having its inlet end remote from the heating chamber and in communication with a source of air supply and their outlet' ends arranged toward the heating chamber, one of said cooling conduits being provided at its inlet end with air controlling means and its other end connected to said combustion chamber and the other cooling conduit having its delivery end connectedto a hot 1m air delivery outlet'extending from the oven.
  • a cooling chamber into which the goods that have been heated are passed and cooling conduits located in such chamber andarranged one within another 11% and throughwhich streams of fluid can be passed to effect cooling of the goods and of being themselves thereby heated, said conduits being out of communication with the cooling chamber.
  • a heating chamber In an oven, a heating chamber, a cooling chamber communicating therewith, a combustion chamber in the heating chamber, a cooling conduit in the cooling chamber discharging into the combustion chamber 135 and a cooling conduit conducting air .independently through the cooling chamber.
  • a heating chamber In an oven, a heating chamber, a coolmg chamber communlcatmg therewith, a combustion chamber in the heating cham- 1 her, a cooling conduit in the cooling chamber, a junction piece connecting the combustion chamber and conduit together and tending through the'cooling chamber and through which air can be drawn from the external atmosphere, one of said conduits being in communication with the combustion chamber and means for introducing a gaseous fluid other than air to the interior of said oven.
  • An oven comprising a heating chamber, a cooling chamber forming a continuation thereof, the outer ends of said chainbers being normally closed when the oven is in use for treating material therein, a combustion chamber arranged within the heating chamber a d out of communication with both the heating and cooling chambers and provided with an inlet for fuel, in fluid condition, conduits extending through the cooling chamber and through which air can be drawn from the external atmosphere, one of said conduits being in communication with the combustion chamber and means for introducing a gaseous fluid other than air to the interior of said oven.

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Drying Of Solid Materials (AREA)

Description

c. DRESSLER.
Y OVEN.
APPLICATION FILED FEB. 17, 1914.
LWHEM" Patemmm. 1,1916.
CONRAD JDIBESSLER, 01E MARLOW, ENGLAND.
OVEN.
Specification of Letters Patent.
Patented Aug, Ill, 1916.
Application filed FebruarylZ, 1914:. Serial-No. 819,286.
' following is a specification.
This invention relates to ovens wherein, for the purpose of enabling the heat resulting from the combustion of gaseous or other fuel, to be economically,-uniformly and effectively utilized,'the'heating chamber of the oven is provided with one or more longitudinally arranged combustion chambers so arranged therein that when the'oven is in use,
air will be heated and caused to'ascend between the outer side of the combustion chamber, or each combustion chamber, and the adjacent, side wall of the heating chamber to the top of the oven, then descend among the goods to be heated in the oven and afterward pass under the combustion chamber to the outer side thereofto be reheated and again circulated. In ovens of this kind air is sometimes allowed to flow through a portion of the oven and come in contact with the heated goods while they are in the cooling zone of .the oven and itself become heated, such heated airbeing admitted to the combustion chamber or chambers for effecting combustion therein. lit will'thus be'seen that while in a portion of the oven, namely the heating portion, the gaseous contents of the combustion chamber or chambers and the air in the oven are keptentirely separated from one another, this is not the case in the cooling zone where the air in the oven is actually drawn into the said chamber or chambers to burn the gas or other fuel therein and that thus there is communication between the oven and the said chamber or chambers. I
While such an oven is suitable for heating and treatingnot only pottery and the like but also ores and other materials or articles that require or may be subjected to the oXidizing action of air on their passage along the cooling zone it is not suitable for use in cases where it is desired to subject ores or other materials or articlesthereinafter referred to as materials) to the action of a reducing, neutral, acid or alkaline atmosphere, or for heating materlals, for example sulfids or carbonates, that cause the production or evolution of gases, not suitable for admission to the combustion chamber or chambers, or, it may be, to the external atmosphere.
Now the present invention has for its obect to enable an oven of the kind mentioned to be kept throughout its length, and including itscooling zone, entirely independent so far as its gaseous contents are concerned, from the combustion chamber or chambers and from the air supply thereto, so that the oven can be used for heating materials in an atmosphere of any desired character,for
example, reducing, neutral, oxidizing, acid or alkal1neand so that the fired or heated materials can be cooled in such an atmosphere, part of the heat abstracted from the material when coolingthe same being utilized for heating the air supplied to the combustion chamber or chambers and the remainder being utilized for other purposes, for instance drying, warming or preheating fresh material, or gas for combustion, or discarded, as may be desired in any particular case. For this purpose, the coolingzone of the oven is provided with two or more tubes or conduits, or sets of tubes or conduits (hereinafter referredto as conduits),
' through which cooling air 1s caused to flow for the purpose of cooling the material after treatment in the heating zone and become heated by heat radiated from the said material, and also by heat derived from convection currents circulating around the said conduits, the air flowing through and heated in one conduit or set of conduits being delivcred to the combustion chamber or chambers for effecting combustion therein and the air flowing through and heated in the-other conduit or conduits being led away and used for drying or other purposes or discarded as desired. The ends of the oven are or may be normally closed so as to confine the atmosphere therein and the oven wall may be provided at suitable points with holes or passages for the inlet, or inlet and outlet, of the gaseousfluid to be used in the oven except, it may be, in the case where air is to be used, unless the air is to be used under pressure.
The arrangement of conduits in the cooling zone ofthe oven may also be used for heating combustible gas simultaneously with the air, the air and combustible gas being brought into contact at the end of the cooling-zone, after they have acquired to occur when fire clay or analogous material is used for making the conduits.
The conduits, or some of them, for eXample those for supplying heated air and gas to the combustion chamber or chambers, may be arranged one Within the other.
By the means described the heated material can be effectually cooled by air that is prevented from coming into contact with and being contaminated by such material,
the air so heated being available for various useful purposes.
In the accompanying drawings, Figure 1 shows in sectional plan view and Fig. 2'
in cross section partly on the lines A A and partly on the line B B of Fig. 1 and to a larger scale, an oven of the kind referred to embodying the present invention. Fig. 3 is a horizontal section, and Fig. 4 a cross section-on the line C C of Fig. 3, showing,
to a still larger scale, part of the oven.
Fig. 5 shows in cross section two conduits arranged one within the other. Fig. 6 is a cross section on the line D D of Fig. 1.
In the example shown, there are arranged within the cooling zone or chamber a of the oven 6 and at each side of the passageway 0 for goods therethrough, two conduits d and e for passage of air from the exterior of the oven. The inner end of each conduit 0?! is connected to one end of a junction piece f the other end of which is connected to the adjacent end of the corresponding combustion chamber h which is the conduits 6 can be led to any desired place and utilized or not as desired. The
conduits d, e are supported above the floor m at each side of the passage way 0 and spaced apart and from the walls of the cooling zone of the oven so that the air or other gaseous medium heated in the cooling zone by the hot goods or materials therein can. circulate or pass freely between and around such conduits and: impart its heat thereto so that the goods or inaterialwill be cooled and the heat thereof utilized. The outer ends of the conduits d. are, or may be fitted with valves'n for controlling. the amount of air supplied to the combustion chambers h.
The passage may be a suction passage connected to a fan for causing air to flow at any desired rate through the conduits e to suit requirement. The conduits d and a may conveniently be made of fireclay or other refractory material. They may however be of metal and of circular or other sha'pe and be of smaller cross. section and more numerous than those shown.
Fig. 5 shows how one of the air conduits d of Figs. 1 and 3 can be provided with an internal conduit 0 through which combustible gas can be supplied from any convenient source to the corresponding junction piece f to be burnt therein by the aid of the air supplied through the said air conduit. As this air will be heated by flowing in contact with the conduit d it will in turn heat the gas conduit 0 so that the gas flowing through the latter conduit will also be heated by contact therewith. The conduit 0 can be supported within the conduit (Z in any convenient manner. The oven is or may be closed at its ends preferably by double doors or air locks 72 for the purpose of effectively protecting the contents of the oven from the external atmosphere.
The oven may be provided with any suit-' able arrangement of inlets for admitting thereto any desired gaseous medium for producing in the oven an atmosphere of any desired character, as for example reducing, neutral, acid or alkaline. For this purpose in the example there is shown an inlet pipe 1' having exit apertures '2" opening into the oven.
A special outlet for gaseous medium from the oven may also if desired be provided in one or both of the ends or end portions of the oven, as.shown for example at s, or at other desired point or points. Sometimes, however, no special outlet will be necessary.
The arrows 1 indicate the course of the air through the conduits (Z to the junction pieces 7 and combustion chambers h; the arrow 2 the direction of the combustible gas admitted to the junction pieces f wherein such gas is mixed with the heated air supplied through the conduits (l; the arrows 3 the courseof the products of combustion from the combustion chambers; the arrows 4 the course of the air to and from the conduits e; and the arrow 5 the direction of any gaseous medium admitted to the interior. of the oven through the supply pipe 1" and inlet apertures 1*.
The combustion chambers It are connected at their outlet ends through apertures t toa pipe 11. connected to a chimney v or other suitable exhausting device that will cause the products of combustion to flow in the direction of-the arrows 3. The goods or material to be heated travel through the oven in a direction from right to left in i Fig. 1 so that they are first heated and then cooled.
What I claim is':
1. An oven comprising a heating chamber, a cooling, chamber forming a. continuation thereof, a combustion chamber, supported in the heating chamber so that gaseous fluid can circulate around it and out of communication with the heating and cooling chambers, a cooling conduit supported in the cooling chamber and connected to the combustion chamber and means for introducing fuel in a. fluid condition to the combustion chamber.
2. In an oven comprising a heating chamher and a cooling chamber forming a continuation (thereof, a combustion chamber and a cooling conduit arranged respectively in said heating andcooling chambers and *in alin ement with each other and ajunction piece connecting said chamber and conduit together. I
3. In an oven comprising a heating cham her and a cooling chamber through which 35' cooling, conduit in alinement therewith and a junction piece connecting said combustion chamber and conduits and having an, inlet for fuel in a. fluid condition, to be consumed in the combustion chamber.
5. An oven comprising a heating zone and a cooling zone, a combustion chamber supported at one side of the heating zone, above the floor and at a, distance from the adjacent side of the oven and having its interior out of communication with the interior of the oven,an air conduit also out of communication with the interior of the oven but in communication with the interior ofthe combustion chamber and extending freely through the cooling zone-at one side thereof and means for supplying combustible as to the air that has passed througl the air conduit.
chamber and a-= fuel inlet duct eitending,
through the'wall of the heating chamber into the combustion chamber.
7. In an oven comprising a heating cham her and a cooling chamber forming a con tinuation thereof, a combustion chamber and a cooling conduit arranged respectively insaid heating and cooling chambers and the cooling chamber being in communication with the external atmosphere at one end and with the combustion chamber at the other end and means for throttling the entrance of air tothe cooling conduit.
8. In an oven comprising aheating chamher and a cooling chamber forming a continuation thereof, a oambustion chamber arranged in the hearth g chamber, a cooling conduit arranged in said cooling chamber and through which air can pass, a junction piece connecting said combustion chamber and cooling conduit and having an inlet for a fuel in a fluid condition and means for throttling the entrance of air to the cooling conduit.
9. In an oven comprising a heating chamher and a cooling chamber in alinement with each other, a number of cooling conduits supported longitudinally within the cooling chamber with their inlet ends remote from the heating chamber and their outlet ends toward the heating chamber and through which cooling fluid can flow and become gradually heated.
. 10. In an oven comprising a heating chamber and a cooling chamber arranged in alinement with each other and through which goods can pass successively, a combustion chamber arranged longitudinally in the heating chamber and out of communication with both chambers, and two air conduits supported within and-extending 10W longitudinally of the cooling chamber and each having its inlet end remote from the heating chamber and in communication with a source of air supply and their outlet' ends arranged toward the heating chamber, one of said cooling conduits being provided at its inlet end with air controlling means and its other end connected to said combustion chamber and the other cooling conduit having its delivery end connectedto a hot 1m air delivery outlet'extending from the oven.
11. In an oven, a cooling chamber into which the goods that have been heated are passed and cooling conduits located in such chamber andarranged one within another 11% and throughwhich streams of fluid can be passed to effect cooling of the goods and of being themselves thereby heated, said conduits being out of communication with the cooling chamber.
12. In an oven, a heating chamber, a cooling chamber communicating therewith, a combustion chamber in the heating chamber, a cooling conduit in the cooling chamber discharging into the combustion chamber 135 and a cooling conduit conducting air .independently through the cooling chamber.
13. In an oven, a heating chamber, a coolmg chamber communlcatmg therewith, a combustion chamber in the heating cham- 1 her, a cooling conduit in the cooling chamber, a junction piece connecting the combustion chamber and conduit together and tending through the'cooling chamber and through which air can be drawn from the external atmosphere, one of said conduits being in communication with the combustion chamber and means for introducing a gaseous fluid other than air to the interior of said oven.
15. An oven comprising a heating chamber, a cooling chamber forming a continuation thereof, the outer ends of said chainbers being normally closed when the oven is in use for treating material therein, a combustion chamber arranged within the heating chamber a d out of communication with both the heating and cooling chambers and provided with an inlet for fuel, in fluid condition, conduits extending through the cooling chamber and through which air can be drawn from the external atmosphere, one of said conduits being in communication with the combustion chamber and means for introducing a gaseous fluid other than air to the interior of said oven.
Signed at London, England, this 27th day of January, 1914:.
CONRAD DRESSLER. Witnesses:
H. D. JAMESON, O. J. WORTH.
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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3212763A (en) * 1964-03-05 1965-10-19 United States Steel Corp Reheating furnace

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3212763A (en) * 1964-03-05 1965-10-19 United States Steel Corp Reheating furnace

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