US1385480A - Furnace with rotatable hearth - Google Patents

Furnace with rotatable hearth Download PDF

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US1385480A
US1385480A US1385480DA US1385480A US 1385480 A US1385480 A US 1385480A US 1385480D A US1385480D A US 1385480DA US 1385480 A US1385480 A US 1385480A
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hearth
chute
mouth
aperture
articles
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    • CCHEMISTRY; METALLURGY
    • C21METALLURGY OF IRON
    • C21DMODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D9/00Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
    • C21D9/0037Rotary furnaces with vertical axis; Furnaces with rotating floor

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  • the object of this invention is to furnish a furnace adaptedfor heating in succession ⁇
  • the hearth is mounted to turn and formsv the bottom of the heating-chamber, and is provided with.V gearing to rotate it at pleasure.
  • the aperture maybe in the center of the hearth, and in such case the mouth of the chute or channel is located beneath the central aperture.
  • the hearth may, however, be
  • Means for discharging the material automatically tothe chute is provided by hinging a carrier at one edge of each aperture and providing a rail fixed beneath the hearth to sustain the carriers in thepplane of the hearth excepting over the mouth of the chute'.
  • each carrier in turn when it reaches suoli point to drop into the mouth of thek chute and discharge itsV load to the chute.
  • the carriers are prefer.- ably made of pan-shape to retain small articles safely until dumped into the chute.
  • Figure l representing a section of a furnace, having hearth with aperture in the center, on line 1 1 in Fig. 2; which figure isa plan in section on line 2-2 in Fig. l.
  • Fig. Bis a vertical sectionY on line 8-3 in Fig. 2;
  • Fig. 4 is a plan of a furnace with pans'hinged in the hearth, in section on line 4 4 in Fig. 5;
  • Fig. 5 is a section on line 5 ⁇ - 5 in Fig. 4;
  • Fig. 6 is a plan in section on line 6-6 in Fig. 7; and
  • Fig. 7 is a section on line 7-7 in Fig. 4.
  • Figs. l to 3 of the drawing show one form of the apparatus in which the rotatable hearth has its aperture located at the center, andthe chute extended beneath suchaperture to receive the articles discharged therefrom.
  • Figs; 4 to 7 inclusive show the rotatable hearth provided with eight pans pivoted t carry the material excepting over the moutho f the chute, at which point the vpans are ipped downwardly to discharge their conen s.
  • the heating chamber a is shown of circular form and has at one side a combustion-chamber b provided with bnrner-openings
  • This furnace is especially adapted for heat-treating metal articles which require a relatively high temperature.
  • the hearth is shown as an annular metal troughc having a floor of refractory material c.
  • the trough which constitutes the hearth 1s supported upon annular rails e by means of wheel e', and a chute CZ is mounted beneath the aperture d in the center of the hearth.
  • Gearing ,f andy is provided to rotate the hearth at pleasure.
  • a doorway a is extended from the heating-chamber atk the level of the hearth and provided with a door a2, and a table/t is shown in front of the doorway arranged to support the articles z" for insertion Vin the furnace.
  • a hydraulic pusher j is shown to push the articles into the furnace upon the hearth.
  • dampers o at their upper ends. These lues are extended downwardly beneath the rotating hearthto maintain thel pressure of the gases in the heating-chamber until they are discharged therefrom.
  • outlet-fines u are shown extended from the heating-chamber just above the level of the rotating hearth but looped downwardly like a trap to maintain the pressure of gases in the heating-chamber until they are discharged Atank Zo is shown beneath the mouth of the chute which extends outside of the furnace.
  • A'flap or hinge-leaf c is applied to the outlet of the chute to exclude air, and articles discharged fromV the chute may thus be thrown into the bath in the tank without any material exposure to the air.
  • Figs. 1, 2 and 3 requires the provision of a pusher y' to push the articles into the furnace upon the hearth, and applicable to push the articles upon different portions of the hearth toward the center aperture for discharging them to the chute; but Figs. 4C to 7 inclusive show a hearth provided with pivoted pans Z to discharge the material.
  • the material to be treatedcan therefore be continuouslyv fed upon the. hearth and automatically discharged therefrom by the tipping or dropping of the pan over the mouth of a chute.
  • the hearth is shown provided with a central hub p and an annular rim p connected to the hub by a series of spokes or rods Q which form the hinge-'pivots of a corresponding series of pans Z.
  • a ball-race 1' is shown in Fig. 5 rotated in the wall of the heating-chamber with the balls supporting the rim p.
  • rlhe hub p is supported by a shaft s journaled in a step s and turned by means of a worm t and worm-wheel Z upon the shaft. rlhis gearing provides means to rotate the hearth at any desired speed.
  • the iioor n of the heating-chamber is provided with two annular rails n which contact with the under side of the pans, and hold them in the plane of the wheel excepting over. the mouth b of the chute.
  • the hinges Z2V of the pan turn freely upon the rods or spokes g and the pans rest loosely upon the rails n which hold them level until they reach the mouth b of the chute.
  • the pans may be successively charged with small articles by feeding them continuously through the wall of the heatingchamber' by a spout m extended over the path of the pans, as indicated in Fig. 7
  • pans are filled immediately after they are dumped, as indicated in Fig. 7, and the hearth is turned at such rate that the articles are sufficiently heated when they are carried around one circuit to the dumping point CZ.
  • Fig. 7 one of the pans is shown dropped into said mouth and in contact with the convex surface of a cam 0, which is attached to the ioor in such position as to lift each pan in succession to the plane of the hearth as it is moved away from the mouth Z of the chute.
  • rIhe rails n as shown in Fig. 6, are interrupted over the mouth of the chute to permit the dropping of each pan into the said mouth.
  • the spout m is shown directed toward the pan adjoining the mouth of the chute, which pan would be emptied in passing such mouth and therefore in readiness to be filled again.
  • Figs. t and 5 show the same combustionchamber Z), burner-inlets b and doorway a as Figs.v 1 and 2; but Fig. 7 shows the spout m inserted through the wall of the heating chamber in place of a doorway.
  • the mouth of the chute is differently located and differently shaped with the construction of Figs. l and 7 but the mouth of the chute serves the same purpose in all the constructions shown, in furnishing a channel through which the heated material can be discharged from the rotatable hearth to a suitable receptacle for the further handling of the articles; and the shape and direction of the chute are therefore immaterial.
  • the chute would terminate in a water-tank directly below the surface of the water and the articles would be removed from the tank by any suitable means after cooling.
  • chute is used herein to signify any channel through which the material passes when discharged from the rotating hearth.
  • heat-treating furnace provided with a rotatable hearth having a discharge aperture therethrough, means for rotating the hearth and a chute beneath the aperture to receive the discharged material.
  • a heat-treating furnace provided with a rotatable hearth having a discharge aperture therethrough, means for rotating the hearth, means for charging the material to be treated upon the hearth, and a chute beneath the aperture to receive the discharged material.
  • a heat-treating furnace provided with a rotatable hearth having a discharge aperture therethrough, means for heating the chamber, an inletr for introducing the material to the hearth, a chute beneath the aperture to receive the discharged material, and means for rotating the hearth.
  • a heat-treating furnace provided with a rotatable hearth having a discharge aperture therethrough, means for heating the chamber above the hearth, an inlet for introducing the material to the hearth, mechanism for pushing the material through such inlet upon the hearth, a chute beneaththe aperture to receive the discharged material,
  • a heat-treating furnace provided with a rotatable hearth having a plurality of apertures extended therethrough at equal distances from the axis of the hearth, a
  • G. it. heat-treating furnace provided with a rotatable hearth having an aperture extended therethrough at one side of its center, a chute having its mouth arranged beneath the hearth upon a line with the path of the said aperture, a carrier hinged upon the hearth to swing in the said aperture, and means for supporting the carrier during the rotation of the hearth until the carrier passes over the mouth of the chute.
  • a heat-treating furnace provided with a rotatable hearth having a plurality of apertures extended therethrough at equal distances from the axis ofthe hearth,carriers hinged to the hearth to swing inthe said apertures and means for supporting the carriers during the rotation of the hearth until each passes over the mouth of the chute.
  • a heat-treating furnace provided with a rotatable hearth having an aperture ex- 9.
  • a heat-treating furnace provided witha rotatable hearth having a plurality of apertures extended therethrough at equal distances from the axis of the hearth, carriers hinged upon the hearth to swing in the said apertures, one or more rails fixed below the hearth to support the carriers excepting over the mouth of the chute, and the said mouth at one side being provided with a cam to restore the carriers to the level of the hearth.
  • a heat-treating furnace provided with a rotatable hearth comprising a skeleton wheel with hub, rim and spokes, a chute having its mouth arranged beneath the spaces between the spokes at one side of the hub, carriers hinged upon the spokes to drop successively into the said mouth, and means for supporting the carriers at the plane of the wheel excepting over the mouth of the chute.
  • a heat-treating furnace provided with a rotatable hearth comprising a skeleton wheel with hub, rim and spokes, a' ball-race supporting the rim of the wheel, a shaft and step supporting the hub of the wheel and connected with means for rotating the hearth at pleasure, a chute having its mouth arranged beneath the spaces between the spokes at one side of the hub, carriers hinged upon the spokes to drop successively into the said mouth, and means for supporting the carriers at the plane of the wheel eX- cepting over the mouth of the chute.
  • a heat-treating furnace provided with a rotatable hearth having a discharge aperture therethrough, means for heating the chamber above the hearth, a chute beneath the aperture to receive the discharged material, and an outlet-flue disposed to draw the gases below the level of the hearth in their escape from the furnace chamber.

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Mechanical Engineering (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Tunnel Furnaces (AREA)
  • Heat Treatments In General, Especially Conveying And Cooling (AREA)

Description

M. 'A. IURTLE.
FURNACEv WITH ROTATABLEHEARTH.
APPLlcATloN FILED FEB. lo. 1920.
11,385,480. Patented July 26, 1921.
3 SHEETS-SHEET I.
UNITED STATES PATENT OFFICE.
NORTON A. TUETEE, 0E EASE ORANGE, NEW JERSEY, Assiexvoa rc w. s. RQGKWELI,
COMPANY, 0E NEW YORK. N. Y., A consommer or Naw nommen Wi'rn; no'rA'rABLn HEARTH.
Specification of Letters Patent. 1
Application filed Februaryl, 1920. Serialv 110,357,763.
To all whom t may concern.'
Be it known that I, MonroN A. TURTLE, a subject of the `King of Great Britain, 'residing at 19 Dodd street, East Orange,
county of Essex, and Statefof New Jersey,`
have invented certain new'a'nd useful Improvements in Furnaces with .Rotatable' Hearths, fully described and represented in the following specification and the accompanying drawings, forming a part of the same.
The object of this invention is to furnish a furnace adaptedfor heating in succession` The hearth is mounted to turn and formsv the bottom of the heating-chamber, and is provided with.V gearing to rotate it at pleasure.
The aperture maybe in the center of the hearth, and in such case the mouth of the chute or channel is located beneath the central aperture. The hearth may, however, be
formed with a series of apertures extendedv therethrough at equal distances from itscenter, and in such case the mouth of the chute is arranged beneath the hearth uponaline with the path of the said apertures.
Means for discharging the material automatically tothe chute is provided by hinging a carrier at one edge of each aperture and providing a rail fixed beneath the hearth to sustain the carriers in thepplane of the hearth excepting over the mouth of the chute'.
This construction ycauses each carrier in turn when it reaches suoli point to drop into the mouth of thek chute and discharge itsV load to the chute. The carriers are prefer.- ably made of pan-shape to retain small articles safely until dumped into the chute.
Two embodiments ofthe invention are shown herein, Figure l representing a section of a furnace, having hearth with aperture in the center, on line 1 1 in Fig. 2; which figure isa plan in section on line 2-2 in Fig. l. Fig. Bis a vertical sectionY on line 8-3 in Fig. 2; Fig. 4 is a plan of a furnace with pans'hinged in the hearth, in section on line 4 4 in Fig. 5; Fig. 5 is a section on line 5`- 5 in Fig. 4; Fig. 6 is a plan in section on line 6-6 in Fig. 7; and Fig. 7 is a section on line 7-7 in Fig. 4.
Figs. l to 3 of the drawing show one form of the apparatus in which the rotatable hearth has its aperture located at the center, andthe chute extended beneath suchaperture to receive the articles discharged therefrom. Figs; 4 to 7 inclusive show the rotatable hearth provided with eight pans pivoted t carry the material excepting over the moutho f the chute, at which point the vpans are ipped downwardly to discharge their conen s.
vTn Figs. l to 3 the heating chamber a is shown of circular form and has at one side a combustion-chamber b provided with bnrner-openings This furnace is especially adapted for heat-treating metal articles which require a relatively high temperature.
The hearth is shown as an annular metal troughc having a floor of refractory material c. The trough which constitutes the hearth 1s supported upon annular rails e by means of wheel e', and a chute CZ is mounted beneath the aperture d in the center of the hearth. Gearing ,f andy is provided to rotate the hearth at pleasure.
A doorway a is extended from the heating-chamber atk the level of the hearth and provided with a door a2, and a table/t is shown in front of the doorway arranged to support the articles z" for insertion Vin the furnace. y
A hydraulic pusher j is shown to push the articles into the furnace upon the hearth.
Any equivalent means maybe used to load the articles successively upon the annular surface ofthe hearth while different sections of its surface are turned adjacent to the doorway. In like manner a suitable pusher would he' operated through the doorway to push theA articles upon successive sections of the hear-th into the aperture o', to be discharged by the chute Outlet-fines u from the heating-chamber a are shown in Figs. 4 and 5 provided with Patented July 2a, i921.n
dampers o at their upper ends. These lues are extended downwardly beneath the rotating hearthto maintain thel pressure of the gases in the heating-chamber until they are discharged therefrom.
In Figs. l, 2 and 3 outlet-fines u are shown extended from the heating-chamber just above the level of the rotating hearth but looped downwardly like a trap to maintain the pressure of gases in the heating-chamber until they are discharged Atank Zo is shown beneath the mouth of the chute which extends outside of the furnace. l
A'flap or hinge-leaf c is applied to the outlet of the chute to exclude air, and articles discharged fromV the chute may thus be thrown into the bath in the tank without any material exposure to the air.
The constructions of Figs. 1, 2 and 3 requires the provision of a pusher y' to push the articles into the furnace upon the hearth, and applicable to push the articles upon different portions of the hearth toward the center aperture for discharging them to the chute; but Figs. 4C to 7 inclusive show a hearth provided with pivoted pans Z to discharge the material. The material to be treatedcan therefore be continuouslyv fed upon the. hearth and automatically discharged therefrom by the tipping or dropping of the pan over the mouth of a chute.
.The hearth is shown provided with a central hub p and an annular rim p connected to the hub by a series of spokes or rods Q which form the hinge-'pivots of a corresponding series of pans Z.
A ball-race 1' is shown in Fig. 5 rotated in the wall of the heating-chamber with the balls supporting the rim p.
rlhe hub p is supported by a shaft s journaled in a step s and turned by means of a worm t and worm-wheel Z upon the shaft. rlhis gearing provides means to rotate the hearth at any desired speed.
With the construction of Figs. l, 2 and 3, the discharge of the articles is necessarily intermittent, as the rotation of the hearth must be stopped to remove the charge upon the hearth before supplying another.
By providing means to support the pans when they are not over the mouth of the chute the operation of the furnace is uninterrupted and continuous. This is effected by hinging the series of pans Z in a series of apertures Z upon the hearth with the mouth d ofthe chute arranged beneath the vpath of the apertures and providing means for dumping the pans successively into the mouth of the chute.
The iioor n of the heating-chamber is provided with two annular rails n which contact with the under side of the pans, and hold them in the plane of the wheel excepting over. the mouth b of the chute.
These parts form a wheel-like skeleton, the sections between the spokes forming the apertures in which the kpans are carried around in the heating-chamber.
The hinges Z2V of the pan turn freely upon the rods or spokes g and the pans rest loosely upon the rails n which hold them level until they reach the mouth b of the chute.
The pans may be successively charged with small articles by feeding them continuously through the wall of the heatingchamber' by a spout m extended over the path of the pans, as indicated in Fig. 7
With such arrangement the pans are filled immediately after they are dumped, as indicated in Fig. 7, and the hearth is turned at such rate that the articles are sufficiently heated when they are carried around one circuit to the dumping point CZ.
In Fig. 7 one of the pans is shown dropped into said mouth and in contact with the convex surface of a cam 0, which is attached to the ioor in such position as to lift each pan in succession to the plane of the hearth as it is moved away from the mouth Z of the chute.
rIhe rails n, as shown in Fig. 6, are interrupted over the mouth of the chute to permit the dropping of each pan into the said mouth.
The spout m is shown directed toward the pan adjoining the mouth of the chute, which pan would be emptied in passing such mouth and therefore in readiness to be filled again.
lt is obviously immaterial how the heating-chamber is kept at the required temperature, to operate upon the articles which re* quire treatment, without injury to the structure.
Figs. t and 5 show the same combustionchamber Z), burner-inlets b and doorway a as Figs.v 1 and 2; but Fig. 7 shows the spout m inserted through the wall of the heating chamber in place of a doorway.
It is immaterial what means be employed to continuously supply the material or articles to the movable hearth, or to discharge such articles from the hearth downwardly into the chute.
It will be observed that the mouth of the chute is differently located and differently shaped with the construction of Figs. l and 7 but the mouth of the chute serves the same purpose in all the constructions shown, in furnishing a channel through which the heated material can be discharged from the rotatable hearth to a suitable receptacle for the further handling of the articles; and the shape and direction of the chute are therefore immaterial.
Where it is desired to quench such articles without exposure to the atmosphere the chute would terminate in a water-tank directly below the surface of the water and the articles would be removed from the tank by any suitable means after cooling.
The term chute is used herein to signify any channel through which the material passes when discharged from the rotating hearth.
Having thus set forth the nature of the intention what is claimed herein is:
l. n. heat-treating furnace provided with a rotatable hearth having a discharge aperture therethrough, means for rotating the hearth and a chute beneath the aperture to receive the discharged material.
2. A heat-treating furnace provided with a rotatable hearth having a discharge aperture therethrough, means for rotating the hearth, means for charging the material to be treated upon the hearth, and a chute beneath the aperture to receive the discharged material.
A heat-treating furnace provided with a rotatable hearth having a discharge aperture therethrough, means for heating the chamber, an inletr for introducing the material to the hearth, a chute beneath the aperture to receive the discharged material, and means for rotating the hearth.
4. A heat-treating furnace provided with a rotatable hearth having a discharge aperture therethrough, means for heating the chamber above the hearth, an inlet for introducing the material to the hearth, mechanism for pushing the material through such inlet upon the hearth, a chute beneaththe aperture to receive the discharged material,
and means for rotating the hearth above the mouth of the chute.
A heat-treating furnace provided with a rotatable hearth having a plurality of apertures extended therethrough at equal distances from the axis of the hearth, a
-chute havingi'ts mouth arranged beneath the hearth upon a line with the path of the said apertures, and means for discharging the material through the apertures successively as each passes over the mouth of the chute.
G. it. heat-treating furnace provided with a rotatable hearth having an aperture extended therethrough at one side of its center, a chute having its mouth arranged beneath the hearth upon a line with the path of the said aperture, a carrier hinged upon the hearth to swing in the said aperture, and means for supporting the carrier during the rotation of the hearth until the carrier passes over the mouth of the chute.
7. A heat-treating furnace provided with a rotatable hearth having a plurality of apertures extended therethrough at equal distances from the axis ofthe hearth,carriers hinged to the hearth to swing inthe said apertures and means for supporting the carriers during the rotation of the hearth until each passes over the mouth of the chute.
8. A heat-treating furnace provided with a rotatable hearth having an aperture ex- 9. A heat-treating furnace provided witha rotatable hearth having a plurality of apertures extended therethrough at equal distances from the axis of the hearth, carriers hinged upon the hearth to swing in the said apertures, one or more rails fixed below the hearth to support the carriers excepting over the mouth of the chute, and the said mouth at one side being provided with a cam to restore the carriers to the level of the hearth.
l0. A heat-treating furnace provided with a rotatable hearth comprising a skeleton wheel with hub, rim and spokes, a chute having its mouth arranged beneath the spaces between the spokes at one side of the hub, carriers hinged upon the spokes to drop successively into the said mouth, and means for supporting the carriers at the plane of the wheel excepting over the mouth of the chute.
1l. A heat-treating furnace provided with a rotatable hearth comprising a skeleton wheel with hub, rim and spokes, a' ball-race supporting the rim of the wheel, a shaft and step supporting the hub of the wheel and connected with means for rotating the hearth at pleasure, a chute having its mouth arranged beneath the spaces between the spokes at one side of the hub, carriers hinged upon the spokes to drop successively into the said mouth, and means for supporting the carriers at the plane of the wheel eX- cepting over the mouth of the chute.
l2. A heat-treating furnace provided with a rotatable hearth having a discharge aperture therethrough, means for heating the chamber above the hearth, a chute beneath the aperture to receive the discharged material, and an outlet-flue disposed to draw the gases below the level of the hearth in their escape from the furnace chamber.
in testimony whereof I have hereunto set my hand.
MORTON A. TURTLE.
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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2944805A (en) * 1956-01-23 1960-07-12 Midland Ross Corp Heating method and apparatus
US3005894A (en) * 1957-12-16 1961-10-24 Westinghouse Electric Corp Cartridge case hardening apparatus
US3170976A (en) * 1961-04-13 1965-02-23 Gleason Works Quenching machine

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2944805A (en) * 1956-01-23 1960-07-12 Midland Ross Corp Heating method and apparatus
US3005894A (en) * 1957-12-16 1961-10-24 Westinghouse Electric Corp Cartridge case hardening apparatus
US3170976A (en) * 1961-04-13 1965-02-23 Gleason Works Quenching machine

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