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US883110A - Electric furnace. - Google Patents

Electric furnace. Download PDF

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Publication number
US883110A
US883110A US34575206A US1906345752A US883110A US 883110 A US883110 A US 883110A US 34575206 A US34575206 A US 34575206A US 1906345752 A US1906345752 A US 1906345752A US 883110 A US883110 A US 883110A
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Prior art keywords
furnace
electrodes
chamber
arms
electric
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Expired - Lifetime
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US34575206A
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Herman L Hartenstein
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CONTINENTAL INVESTMENT Co
CONTINENTAL INVEST Co
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CONTINENTAL INVEST Co
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Priority to US34575206A priority Critical patent/US883110A/en
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    • HELECTRICITY
    • H05ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05BELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B7/00Heating by electric discharge
    • H05B7/02Details
    • H05B7/10Mountings, supports, terminals or arrangements for feeding or guiding electrodes

Definitions

  • This invention relates tov electric furnaces, and more particularly to that class of such furnaces which employ movable or adjustable electrodes capable of being operated from the exterior during the use of the furnace.
  • One of the objects of the invention is to provide an improved electric furnace having movable or adjustable electrodes capable of being operated from the exterior,and allv of whose operating parts will be Wholly inclosed within the furnace, thus avoiding the use of stuffing boxes and like elements used where the moving parts pass through the walls ⁇ of the furnace in the constructions heretofore employed.
  • Another object of the invention is to provide an im roved furnace of the vdescribed other objects which will hereinafter appear,
  • the invention consists in the features of novelty in the construction, combination and.
  • FIG. 1 is avertical Lsectional view of an electric furnace embodying this invention.
  • FIG. 2 is a similar .section taken at right-angles to the plane of the-section resented in Fig. 1.
  • Fig. 3 is a section sim' ar to that presented in Fig. 1, showing the parts in a different position.
  • A4 is a plan section taken on the irregular section line '5l-*4, F' 1'.l
  • Fi .i 5 is a plan A' section or ⁇ diagram s owing/tde position of the horizontal leads of the electrodes with relation to the furnace Walls.
  • Fig. 6 is adetail front.elevation ofone of the electrode operating gears.
  • Fig. 6i is a detail cross section of a part of the gear mechanism for shifting the electrodes.
  • Fig. 6'? is a detail longitudinal sectional View of the same.
  • Fig. 7 is an enlarged detail plan view of one of 4the connections used between the horizontal leads and the flexible portions of the electrode conductors.
  • Fig. 8 is a side elevation of the same.
  • Fig. 9 is an enlarged detail side elevation of one of the yokes which support the carbon holders.
  • Fig. 1() is a plan section thereof on the ⁇ irregular line A1 0-1o, Fig. 9.
  • this .pot or earth 1 is sup orted by the horizontal portions of trac sl 3, which have inclined ends serving to allow the hearth to be lowered away from the walls 4 of the su erstructure of the furnace when the heart ⁇ is to be removed, and which also serve to force the upper edge of the pot or hearth into close relation with th'e lower edges of the walls 4 when it is'being replaced.
  • the superstructure or wallsof the furnace are practically air-tight, composed preferably of the inclining wal portions 4 and the cover ort-ion 4, making a completeinclosure havmg an outlet flue 6, whereby the evolved gases may be conducted to the point of consumption.
  • the tie-rods 15, 16, which are located on the same side of the arm, are provided with rollers 18, 19, affording an antifriction support for'the arms, while the oposite side of the arm is provided with a rack-bar 20, which is engaged by a pinion 21 mounted rigidly on a shaft 22 passing across the furnace and journaled in plates 13, 14. Also arran ed on this shaft 22 are two-antifriction rol ers 23, 24, which engage the arm at both sides of the rack-bar 20, and thus afford an anti-friction bearing for the arm on this side, thus holding the arm firmly between the three points of bearing constituted by the rollers 18,' 19, and the two rollers 23, 24.
  • the two shafts 22 are mounted at one side of the furnace in bearings 25, 26, and at the-other side in bearings 27, 28, and also mounted in the bearing 27, 28, at one end, are uill shafts 29, 30, whose inner ends are rigi y secured to one of the plates 13 of each of the yokes which support the arms 11 12. Consequently, it will be seen that by rotation of the shafts 22 the electrodes may be raised and lowered the same or different degrees, and by the rotation of the shafts 29, 30, the yokes will be rotated and the elec- "trodes correspondingly oscillated as on transverse axes.
  • This inde endent manipulation of the two sets of sha ts 22, and 29, 30, may be effected by any suitable mechanism arranged on the exterior of the furnace.
  • this result is accomplished by providing the hollow shafts 29,y 30, each Wit a worm-wheel 31, the inner shafts 22 eachwith a Worm-wheel 32, and these worm- Wheels 31, 32, respectively', with intermeshing worms 33, 34.
  • the worm 33 is provided with a -hand-operating wheel 37, and the Worm 34 with operating wheel 41, so that when wheel 37 is turned the shaft 29 will be rotated, or partially rotated, and the electrode connected therewith correspondingly oscillated, vand ,when wheel ⁇ 41 is turned the electrode arm will be raised or lowered.
  • Wheel 37 is secured to a short shaft 36, which is also secured to a inion 38, meshing with a gear 39 secured to s aft 35.
  • the wheel 41 is secured to a shaft 36, which is also secured to a pinion 42, meshing with a gear 43 loose on shaft 35 but rigidly secured to a pinion 45, which meshes with a gear 44 rigid on a sleeve 34 that carries worm 34, this back-.gearing being resorted to for the sake of greater leverage on the shaft 22, which is required to raise and lower and sustain the greatweight of the electrodes and their supporting parts.
  • These shafts 35, 36, as well as the boxes 27 28, are supported upon suitable carriages 46, 47, mounted to slide upon a track or way 48 ,-While the boxes 25, 26, are mounted in carriages 49, 50,'adapted to slide on a way 51.
  • sliding carriages may be firmly clamped totheir respective ways by U-shaped clips 53, and the sides or walls ofthe furnace are provided with slots 54, 55, to accommodate the movement ofthe shafts 22, 29 30, and these slots are closed by slides or valves 56, 57, respectively, so as to keep the furnace practically air-tight.
  • the leads 58 and 59 are extended through the wall of the furnace in a horizontal direction, and
  • each of the arms 11, 12, is composed of a channeledl bar or I-beam havingflanges 11,
  • ese clip-plates are also formed with curved overlap ing portions 67, 68, respectively, which em race one end of the U-shaped conductor 60, 61 of each of the electrodes, these U-shaped conductors thin strips of copper, or' other suitable mate.
  • the furnace is practically air-tight, or suffi-A ciently so to prevent the combustion of the evolved gases, whlle permitting ample freedom of movement of all of the internal parts, which may be operated at will from the exterior, the hearth or melting pot being supplied with the material to be treated, without permitting the gases to escape, through a suitable chute 69.
  • an inclosure forming a furnace chamber, electric leads extending into said chamber, electrodes situated within the chamber, means for supporting and operating the electrodes, comprlsin members movable transe Wal of ⁇ the furnace chamber, and an electrical connection between the electrodes and said leads, all of the said parts of the electrode supporting and operatin means which move transversely of the wall o the chamber being situated'wholly Within the chamber.
  • the combination of a furnace chamber, electrodes therein, electrode sup orting means comprisin rigid arms situatedpwithin the chamber, an iiexible connections between said arms and leads Y respectively, locatedwithin the chamber.
  • an electric furnace the combination of a portable hearth or melting pot, a furnace chamber situated above said melting pot, and means whereby the melting pot may be raised to form a tight joint 4with the lower edges of said chamben or lowered away from said chamber at will, with'rneans within the said chamber for supporting and operating the electrodes.

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  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Plasma & Fusion (AREA)
  • Vertical, Hearth, Or Arc Furnaces (AREA)
  • Furnace Details (AREA)

Description

oo. o 9 l 4v 2 R.. A M D E T N E T A P N I E T S N E T R A H L E ELECTRIC FURNAGB.
Arum-Anon FILED Nov. so. 1906.
4 SHEETS-SHEET 1.
PATBNTED MAR. 24, 190s. H. L. HARTENSTBIN. A ELECTRIC FURNAGE.
APPLICATION FILED NOV. 30. 1906. 4 BHEBTS SHEET 2.
1 fig" a 110.883.110. PATBNTBD M1111. 24, 1903.
, 11. L. HARTBNSTEIN. ELECTRIC FURNAGB.
APPLICATION FILED NOV. 30. 1906.
4 SHEETS-SHEET 3.
Zay
effwfor: f Mx Z ,zZ/7651465: $49,723
No. 883,110. PATENTED MAR. 24, 1908. H L HARTENSTBIN.
ELECTRIC PURNAGE. APrLwATIoN FILED nov. so. moa.
4 sums-SHEET 4.
,y UNiTED sTATEs -ijATENT oEEiioE.
Y HERMAN L. HARTENSTEIN, OF CONSTANTINE, MICHIGAN, ASSIGNOR, BY MESNE ASSIGrN` MENTS, TO CONTINENTAL INVESTMENT PORATION OF MINNESOTA.
COMPANY, or DULUTH, M1NNEsoTA,-A con.
ELECTRIC FURNAGE.
No'. 883,1 1o.
Specifleaton of Letters Patent.
Patented umass, 160s.
To all whom it may concern: y
Be it known that I, HERMAN L. HARTEN- STEIN, a citizen of the United States, residing at Constantine, in the 'county of St. Joseph and State of Michigan, have invented certain new and useful Improvements in Electric Furnaces, of which the following is a full, clear, and exact specification.
This invention relates tov electric furnaces, and more particularly to that class of such furnaces which employ movable or adjustable electrodes capable of being operated from the exterior during the use of the furnace.
One of the objects of the invention is to provide an improved electric furnace having movable or adjustable electrodes capable of being operated from the exterior,and allv of whose operating parts will be Wholly inclosed within the furnace, thus avoiding the use of stuffing boxes and like elements used where the moving parts pass through the walls` of the furnace in the constructions heretofore employed.
Another object of the invention is to provide an im roved furnace of the vdescribed other objects which will hereinafter appear,
.the invention consists in the features of novelty in the construction, combination and.
arrangement of parts which will first be' described with reference to the accompanying drawings and then more particularly pointed out in the claims. f
g n In the said draWings,-Figure 1 is avertical Lsectional view of an electric furnace embodying this invention. Fig. 2 is a similar .section taken at right-angles to the plane of the-section resented in Fig. 1. Fig. 3 is a section sim' ar to that presented in Fig. 1, showing the parts in a different position. A4 is a plan section taken on the irregular section line '5l-*4, F' 1'.l
Fi .i 5 is a plan A' section or `diagram s owing/tde position of the horizontal leads of the electrodes with relation to the furnace Walls. Fig. 6 is adetail front.elevation ofone of the electrode operating gears. Fig. 6i is a detail cross section of a part of the gear mechanism for shifting the electrodes. Fig. 6'? is a detail longitudinal sectional View of the same. Fig. 7 is an enlarged detail plan view of one of 4the connections used between the horizontal leads and the flexible portions of the electrode conductors. Fig. 8 is a side elevation of the same. Fig. 9 is an enlarged detail side elevation of one of the yokes which support the carbon holders. And Fig. 1() is a plan section thereof on the` irregular line A1 0-1o, Fig. 9.
1 is the hearth or melting pot of the furnace, which may be of the usual or any suitable form, but' which is preferably sup orted upon a truck 2, so that it may be rea il removed when it is necessary or desirab'e to replace the-linin or otherwise re air or inspect it. When in use this .pot or earth 1 is sup orted by the horizontal portions of trac sl 3, which have inclined ends serving to allow the hearth to be lowered away from the walls 4 of the su erstructure of the furnace when the heart `is to be removed, and which also serve to force the upper edge of the pot or hearth into close relation with th'e lower edges of the walls 4 when it is'being replaced. The joint between the Walls 4 and the hearth or cally air-tight y any suitable packing 5, comosed of l{ire-brick or tile laid in some suitable onding material such as cement or fire-clay.
The superstructure or wallsof the furnace are practically air-tight, composed preferably of the inclining wal portions 4 and the cover ort-ion 4, making a completeinclosure havmg an outlet flue 6, whereby the evolved gases may be conducted to the point of consumption. y
, 7, 8, are the carbons of the two electrodes' ot 1 may be rendered practi` whichy forni the heat-producing arc re uired l in the hearth or pot 1, and which, as efore mentioned, are required to undergo various movements or assume different positions of adjustmentl within the'furnace, sometimes' the requirement. being that the be lifted entirely above the upper edge of t e pot'l, as
shown in full lines, and at other times lowscribed in detail in my co-pending application filed on the 19th day of November, 1906, Serial No. 343989, and constitute the subjectmatter of the claimsV thereof. These carbon holders are secured respectively to the lower ends of arms 1 1, 12 capable of being raised and lowered, or of executing the movements before described. Each arm is embraced by a yoke comprising two lates 13, 14, connected together at both sides of the arm by tic- rods 15, 16, 17. The tie- rods 15, 16, which are located on the same side of the arm, are provided with rollers 18, 19, affording an antifriction support for'the arms, while the oposite side of the arm is provided with a rack-bar 20, which is engaged by a pinion 21 mounted rigidly on a shaft 22 passing across the furnace and journaled in plates 13, 14. Also arran ed on this shaft 22 are two-antifriction rol ers 23, 24, which engage the arm at both sides of the rack-bar 20, and thus afford an anti-friction bearing for the arm on this side, thus holding the arm firmly between the three points of bearing constituted by the rollers 18,' 19, and the two rollers 23, 24. The two shafts 22 are mounted at one side of the furnace in bearings 25, 26, and at the-other side in bearings 27, 28, and also mounted in the bearing 27, 28, at one end, are uill shafts 29, 30, whose inner ends are rigi y secured to one of the plates 13 of each of the yokes which support the arms 11 12. Consequently, it will be seen that by rotation of the shafts 22 the electrodes may be raised and lowered the same or different degrees, and by the rotation of the shafts 29, 30, the yokes will be rotated and the elec- "trodes correspondingly oscillated as on transverse axes.
This inde endent manipulation of the two sets of sha ts 22, and 29, 30, may be effected by any suitable mechanism arranged on the exterior of the furnace. In the exemplification of the invention shown in these drawings, this result is accomplished by providing the hollow shafts 29,y 30, each Wit a worm-wheel 31, the inner shafts 22 eachwith a Worm-wheel 32, and these worm- Wheels 31, 32, respectively', with intermeshing worms 33, 34. The worm 33 is provided with a -hand-operating wheel 37, and the Worm 34 with operating wheel 41, so that when wheel 37 is turned the shaft 29 will be rotated, or partially rotated, and the electrode connected therewith correspondingly oscillated, vand ,when wheel `41 is turned the electrode arm will be raised or lowered. Wheel 37 is secured to a short shaft 36, which is also secured to a inion 38, meshing with a gear 39 secured to s aft 35.
The wheel 41 is secured to a shaft 36, which is also secured to a pinion 42, meshing with a gear 43 loose on shaft 35 but rigidly secured to a pinion 45, which meshes with a gear 44 rigid on a sleeve 34 that carries worm 34, this back-.gearing being resorted to for the sake of greater leverage on the shaft 22, which is required to raise and lower and sustain the greatweight of the electrodes and their supporting parts. These shafts 35, 36, as well as the boxes 27 28, are supported upon suitable carriages 46, 47, mounted to slide upon a track or way 48 ,-While the boxes 25, 26, are mounted in carriages 49, 50,'adapted to slide on a way 51. These sliding carriages may be firmly clamped totheir respective ways by U-shaped clips 53, and the sides or walls ofthe furnace are provided with slots 54, 55, to accommodate the movement ofthe shafts 22, 29 30, and these slots are closed by slides or valves 56, 57, respectively, so as to keep the furnace practically air-tight.
The upper ends of the electrode supporting arms 11 12, instead of being projected through the walls of the furnace as heretofore, are arranged wholly within the inclosure, and are connected to the leads shown at 58, 59, in such a way as to permit of their free movement without danger of injuring the leads or 1parts intermediate the leads and the arms. As indicated in Figs. 1 and 5, the leads 58 and 59 are extended through the wall of the furnace in a horizontal direction, and
at their inner ends they are connected to U- shaped or flexible portions 60, 61, respectively, which carry the current to conductors 62, 63, usually employed on each of the arms 11, 12 for placing the carbons in communication with the leads, these conductors 62, 63 being composed of a materialsuch as copper-of high conductivity, while the arms 11, 12, which are required to be of great rigidity, are formed of a material of greater strength, such as steel.
As indicated more clearly-in Figs. 7 and 8, each of the arms 11, 12, is composed of a channeledl bar or I-beam havingflanges 11,
.12, and between these flanges are situated the conductors 62 63 which project slightly above the end of the arm, as indicated in Fig. 8. Where they thus extend above the arm, they are connected to two ,cli -plates having straight portions'64, 65, the fatter of which is embraced between the two conclu ctors 62, 63, as indicated in Fi 7, while the straight portion 64 is Iclamped to the'outer side of the conductor 62 by the same bolts or lscrews 66 which bind the ortion 65 between the conductors 62, 63. T. ese clip-plates are also formed with curved overlap ing portions 67, 68, respectively, which em race one end of the U-shaped conductor 60, 61 of each of the electrodes, these U-shaped conductors thin strips of copper, or' other suitable mate.
rial ossessing the requisite conductivity and iiexi ility. By the means described, the up- ,versely of t per ends of these conductors 60, 61, are secured to their respective conductors 62 63; the lower ends of these conductors 60, 61, are secured to the'leads 58, 59, in any appropriate manner, asby welding, clamping, or otherwise.
By the means described it will be seen that the furnace is practically air-tight, or suffi-A ciently so to prevent the combustion of the evolved gases, whlle permitting ample freedom of movement of all of the internal parts, which may be operated at will from the exterior, the hearth or melting pot being supplied with the material to be treated, without permitting the gases to escape, through a suitable chute 69.
In order that the invention may be understood by those skilled in the art, the details of this embodiment thereof have been thus specifically described, but
What I claim as new .therein and desire to secure by Letters Patent is:
l. In an electric furnace, the combination of an inclosure constituting a furnace chamber, movable electrodes situated within said chamber, conductors leading into said chamber, and yieldingconnections between the electrodes and said conductors.
2. In an. electric furnace, the combination of movable'electrodes, movable means for su porting and operating the electrodes, and a Furnace chamber completely inclosing the said electrodes and their said supporting and operating means.
3. In an electric furnace, the combination of a furnace chamber, stationary electric leads extending through the wall of the chamber, electrodes situatedwithin the chamber, and movable means for supporting and oper ating the electrodes situated wholly within the chamber and electrically connected with said leads. Y
4. In an electric furnace, the combination of an inclosure forming a furnace chamber, electricleads extending into said chamber, electrodes situated within the chamber, and means for supportin and o erating the electrodes situated who ly wit in the chamber and movable with respect to said leads-and electrically connected therewith. e
5. In an electric furnace, the combination of an inclosure forming a furnace chamber, electric leads extending into said chamber, electrodes situated within the chamber, means for supporting and operating the electrodes, comprlsin members movable transe Wal of` the furnace chamber, and an electrical connection between the electrodes and said leads, all of the said parts of the electrode supporting and operatin means which move transversely of the wall o the chamber being situated'wholly Within the chamber.
6. In an electric furnace, the combination of a furnace chamber, electrodes therein, electrode sup orting means comprisin rigid arms situatedpwithin the chamber, an iiexible connections between said arms and leads Y respectively, locatedwithin the chamber.
7'. In an electric furnace, the combination of a furnace chamber, electrodes situated therein, 'arms for supporting said electrodes situated wholly within the chamber, pivots for the arms extending through the wall of the chamber and supporting the same, electric leads extending into the chamber, and electrical connections between the electrodes and said leads, situated within the chamber.
8. In an electric furnace, the combination of a furnace chamber, electrodes situated therein, electrode sup orting arms mounted wholly within the ciiamber and vmovable therein lon itudinally and on transverse axes, and e ectric leads extending into the chamber and connected with the electrodes.
9. In an electric furnace, the combination of a furnace chamber, electrodes situated therein, electrode supporting arms, conductors arranged longitudinally of said arms and connected with the electrodes, electric leads having flexible terminals, clip-plates clamped to the conductors of each of said arms and e overlapping and clamped to the ,iiexible'ten minal of each of said leads, and means for supporting and operating said arms.`
10. In an electric furnace, the combination of -a furnace chamber, electrodes situated therein, electrode supporting arms having the form of channel-bars, electric conductors arran ed in the channels in said-bars and connecte with the electrodes and extending .above the upper extremities of the arms,
electric leads provided with flexible terminals, clip-plates, one of which is provided with a flat portion clamped between said conductors where they-extend above the arm, and the other of which is clamped to the outer side of the other of said conductors, both of said clip-plates for each of said arms having overlappmg curved extremities between which vthe fiexible extremity of the leadbelonging to that arm is clamped, and means for sup portin and operating the arms.
11. n an electric furnace, the combination of a portable hearth or melting pot, a furnace chamber situated above said melting pot, and means whereby the melting pot may be raised to form a tight joint 4with the lower edges of said chamben or lowered away from said chamber at will, with'rneans within the said chamber for supporting and operating the electrodes.
12. In an electric' furnace, the combination of a portable melting pot or hearth, a truck on which the same is supported, inclined i. tracks on which thejtruck rolls, a furnace chamber situated above the ot or hearth, name to this specification, in the rpresence of .1nd into contact with the ower edge of two subscribing witnesses, on this 23rd dey which the hearth is adapted to be fox-eedl oi November A. D. 1906. when the truck rides up said inclines, with HERMAN L. HARTENSTEIN. l5 electrodes, and means Within said chamber Witnesses: f
for supporting and operatin the electrodes. FRANCIS A. HOPKINS,
In testimony lWhereof I ave signed my CEAS. H. LEEM.
US34575206A 1906-11-30 1906-11-30 Electric furnace. Expired - Lifetime US883110A (en)

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2426643A (en) * 1944-05-08 1947-09-02 Norton Co Method and apparatus for fusing refractory materials
US2686825A (en) * 1952-12-26 1954-08-17 Allegheny Ludlum Steel Furnace structure

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2426643A (en) * 1944-05-08 1947-09-02 Norton Co Method and apparatus for fusing refractory materials
US2686825A (en) * 1952-12-26 1954-08-17 Allegheny Ludlum Steel Furnace structure

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