US1561408A - Induction electric furnace - Google Patents

Description

- Patented Nov. 10, 1925.

UNITED-STATES A NT-optics.

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Paris, France, have invented new and-useful Improvements in Induction Electric.

Furnaces, whioh is fullyset fort-h in the following specificationj The present invention relates to a, three phase 7 induction} electric furnace, capable of being-used for melting voliltile or nonrvolatile alloys or metals,- principa'llj inthe case of a mere melting or of super-refining not requiring --a,ny inetallu'rg'ic treatment I 1 ports of the'circuit' I through too complicated chemicalreections;

This 'furnace is p'articularly adapted to be used for melting brass waste, and for similar operations.

This furnace has been so devised as to be operable when connected directly to-a circuit of three phase currents having the usual frequencies and with an acceptable factor of power. Its main feature, which forms the object of the present application, consists in the gu'rangement of three secondary channels orfducts which are common or mingled over'egreat length in the internal ,so as to reduce to the minimumtheireremr-that is to say the losses of heat, whence it .30

.- metal soto'ii'onjvey uforlcingj chzunbe -tion of'they illustrat ng. one en;

high. thermic yield, while fcii'culiition 'of the the 'energy to the r. to facilitetethe decanta securino the convenient gs illi'd 'Jtof-e'vo'i cl oxidatlon. 'l ljeinvention will be readily understood. by reference to the eccolnpanymg draw ngs, bodnnent of, the present 'fractbry shell which- Figs. 1 and 2v are, respectively, a vertical forn'iirig the ohject ofthe invention.

Application illed 'iliic'ust 21, 1923. Serial miss-51. H

nlet-a1, while carrying .onto heat one 'or two oi? the: secondarycircuits, those which areclose to'the working chainber for example;

Around the .coresure arranged at-e suiu able level the'channels'or ducts cl in' which the noetal circulates 'a-nd"which form with theirexternal' branches a curvilinear triangu1ar"figure which facilitates the movement ot-thebath in the direction resulting from the r' oteting field;

-The nternaL-hrenches, as shown in the accoinpanying drawingsfare common to two ,contiguous'circuits,'- which allows to reducc' to the ,l nin imum the total length of the channel's; whence a high thermic yield. The

internal brainches are connected with the ex;

ternal ORQS'SO as to evbidfthe sharp angles and to induce in thislw'ay a movement of circulation for tlie metal.

The external bwlnches of the two circuits and the two branches common to the three circuits open at the lower part of a loading and working chamber e mwhich skim'ming also takes place. i; p c The tapping takes plnc'eat the opposite end of this chambeiget 9.

The level of the molten metal in the working chamber e is norinnlly above the channels or ducts d-which'latter are completely filled with nicnt reduces the oxidation of the. metdlto a. minimum and also avoiidseny likelihood of the slagswhich fio'atoh'th'e top of the molten metal in chamberye from being can and a horizontal section of thefurnace ricdfelorrc through the-channels cl since the light sla'gs come to the-surface of'the molten bath. Prefer2ibly the upper end of working-eh amber e'is normally closed by a suitable door. i

- The whole of the furnace-witch is con- The furnace essentially comprises 'a' weniently heat-insulated and 'iirmonred is brickwork, and provi'derlwitha pl kl tlf openingsfthrough fwliich extends a. magnetic carcass forn edloif three vertical cores a conher-ted together-at their upper and lower part through'tjVQheads is'preferobly formed of example near '1ts center of simultaneously or separately,.for instance in order to moderate or stop the rotating field and consequently the-movement of the currently used in apparatuses of erected upon afiooni'ng-whicli may, in its tum, b@; mounted on cradles? provided with rollers allowing the tilting'or the furnace mey'bevpivoted about an 'axisplaced for gravity so as to insure the balance (or, near the tap-hole if Inetall This arrange it is desired to facilitate, the/direct tapping into'ingot-inoulds.) 4 v An electro-mechamc or other device,-

which is {this kind,

which has not .been shown but may be employedgfor tiltin the furnace. The normal running of t e furnaceia a contimioue one, thereby giving the maxi mum of regularity in the com msition, as only a fraction of the total amount of molten metal allowed to run every time, 21ml giving z-usoa nmxiimniz'output nml a constant value of the Zl)S{Hi)U(l power.

It must b'c understood that detail alterationsmziy be made in the invention without departing from the .acope thereof.

What I claim is:

1. lo a three-phase. induction electric furnace comprising rloecd channelsiiillerl with molten metai 'wlcic'n' act ostlie secondary R s oi. induction transformers, and in which the cliai'mcls form a. circuit around cach core of primer, an arrangement wherein the portions of these circuits which are ct the interior of the "furnace are com- .uiouto two contiguous circuits and hzwc the $211116 section as the portions of the cir cuite which are turned near the exterior of the furnace.

2. In a three-phase induction electric furnace comprising closed channels filled with o molt-en metal which act as tne secondary wires of the induction transformers, and. a common and exccntercd working chamber from which start and. to which lead the secondary channels, and in which the chan nels form a. circuit around each core of the prinmry, an arrangement wherein the portions of the. circuits which arc adjacent the interior of the furnace are common to two contiguous circuits and have the same secand a plurality mcmoa ing it circuit around each core of the pri-' marry, the portions of these circuits ad acent the interior of the furnace being common to two contiguous circuits and having the same section the portions turned nearthe exterior of the furnace.

4:. A three-phase induction electric furmace comprising a refractory shell having formed. therein a melting chamber, a plurality of closed channels terminating in the lower portion of said chamber, and a tap-v ping duct communicating with said. channelscliametrically opposite to said chamber, of primary coils extending through said shell, the metal in said channels forming secondary circuit-s for said coils, each of the two inner portions of the circuits so formed being common to two of said. primary coils.

In testimony whereof I have signed this specification,

RENE LOUIS CHARTIER.

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