US885745A - Electric furnace. - Google Patents

Description

No. 885,745. PATENTED APR. 28 1908. P. GIRODI ELECTRIC FURNACE.

APPLICATION FILED nnc.2o,19o5.

'FiQL .37

YQUFW tially ings.

UNITED srarns Parana PAUL GIROD, OF UGTNE, FRANCE.

ELECTRIC FURNACE.

Specification of Letters Patent.

Patented. April 22%,

Application filed December 20, 1905. Serial No. 292,618.'

electric furnace of the type disclosed in my French patent 329822 and the certificate oi addition thereto, N o. 3425.

The present invention has for its object to provide an electric furnace bymeans of which a plurality of objects such, for example, as crucibles, may be heated in one furnace.

In the accompanying drawings, I have illustrated one embodiment of the invention.

In the drawings Figure 1 is a Vertical longi tudinal section of the furnace; and Fig. 2 a section on the line A-A of Fig. 1.

Referring to the drawin s, 2 indicates a receptacle which forms the eating chamber, within which may be placed a piurality of objects to be heated, for example, the series of crucibles, 1, indicated in the drawings.

Thereceptacle 2 is shown as substantially rectangular, with twonarrow extensions 8, one at each end. The said receptacle is surrounded by insulating masonry 6 arranged to leave a space between its inner walls and the outer walls of the receptacle, which space is filled with a suitable resistance material, for example, a pulverulent gra hite compo sition, as ex lained in my said I iench patent 329822, an the certificate of'addition 3425 The extensions 8, serve to transmit the weight of the receptacle to the masonry, thus leavin the resistance material 5 substanee from pressure due to such Weight. The receptacle bottom may be solid, but it is advantageous to provide perforations 4, to allow the heat frorri the heating resistance 5 to radiate {reel into the chamber 2.

The furnace as pole pieces 9, 9, 10 and 10 with which the terminals of the electric cir;

cuit are connected, as indicated in the draw- The furnace is covered with refracto plates 7 which can be removed easily in or er to allow the insertion or removal of the crucibles.

The resistant heatirig mass may be arranged in any of the waysyindicated in the said French I atent and certificate oi addi' tion, but pre erably in such a manner as to completely surround the chan'iber, the current being led into and out of the same side of the furnace. This resistance may he civided into sections and grouped together as desirable, in such a manner as to produce a regular heating, the current traversing the heating resistances both. at the sides and at the ends in the directions of the planes of said sides and ends, owing to the manner of introduction the current, as indicated by the positive and negative signs on the drawings.

Having thus fully described my invention, What I claim, 1s:*

l. in. an electric furnace, the combine tion, with'a receptacle forming a chamber arranged to receive a plurah'y of objects to be heated, of a mass cf resistance material arranged in layers in contact with the sides, ends and bottom of said receptacle, and a plurality of pole pieces of opposite polaritychamber arranged to receive a plurality of obiects to be heated, said receptacle having a perforated bottom, of resistance material in contact witlri the outer waits l bottom of said receptacle, means for conoucting cur rent to said resistance material, and a cover for the receptacle, said cover being formed in sections.

In testimony whereof I have signed this specification in the presence oi two subscribing Witnesses.

' l fitnesses

Images