US1584535A - Electric furnace - Google Patents

Description

May 11,1926. 1,584,535

J. D. HAYN'SWORTH' ELECTRIC FURNACE Filed March 5, 1925 .ATTORNEY iPatented May 1'1, 1926.

,UNITED STATES PATENT OFFICE. f

" heating elements so arranged therein as to suitable nace chamber.

`stantially pyramidal n neath the grating and reflect thefheat from `prises a layer of JULIUS D. HAYNSWORTH, 0F MANSFIEITD, OHIO, ASSIG-NOR WESTINGHOU'SE ELEC- TRIO/6v MANUFACTURING COMPANY, A, CORPORATION 0F PENNSYLVANIA.

ELECTRIC remmen.

Application flied Maren 5, 1923. seriai'm. e22,78a.

My invention relates to furnaces and particularly to electrically heated resistor furnaces. 'The object of my invention is to provide a furnace comprising a plurality of electric uniformly heat material placed in the furp Inpracticing 4'\my.invention, vI provide a plurality ofrefractory heat-insulating walls b 'enclosing a furnace` chamber.

fing elements are located in chamber supported by the side, end, and top floor grating is located in Electric heatsaid furnace injnace` walls. A y aid chamber intermediate the top and botheating elerefractory Wallsbeneath efractory reflectors of subshape are located bethe heating elements` located beneath the grating upwardly against the grating and against material located thereon.

'llhe single `gure of the accompanying drawing is a vertical sectional view through an electric furnace embodying my invention.

An electric which walls may be built up of vany suitable refractory heat-insulating material usually employed in the art. An inner lining v16 may be'provided and coma suitable high-temperature resisting refractory material of bricks or blocks of similar material, usually employed in the'art.l The hereinbefore mentioned walls are so locatedand spaced'` apart as to provide a furnace chamber 17 of any suitable or desired dimensions .and contour. Y

Means for heating the furnace chamber comprise metallic resistor members `18 built up of nected, parallel-extending convolutions of a resistor material, sncli as iiichrome. The individual bars may be supported within the furnace chamber 17 by extending through grooves on the inner face of a plurality of refractory bars 19 which a're relatively narrow and are spaced apart a suitable distance. The grooved face of the bais 1 9 is in operative engagement with the inner face of the refractory walls 16 and the bars.

or a plurality a number of integral and endacon are held in their. proper operative position by members 21, of Substantially Tshape, the inner ends of which extendintothe inner lining 16 and may extend into the outer walls hereinbefore described. y

he members 21, of T-shape, are loca/ted in vertically spaced position, a suitable distance apart, to receive and a suitable .number of sets of these inemmembei' shall be substantially self-supporting between the refractory supporting bars 19. As illustrated intheidrawing, heating elements, as hereinbefore described,

located in the top wall or ceiling, in the side and the end walls.

The heating elements hereinbefore described are more particularly disclosed and claimed iii-a copending application, Serial No. 584,620, :tiled by T. A. Reid on August 28, 1922, and assigned to the Electric & Mfg. Co. floor grating 22 o serves to support material placed within tne furnace chamber to. be heat treated therein.

eating elements, as hereinbefore described, are located in the side and end walls of the furnace structure below the floor grating vand inthis position they will not be subject freshly japaniied or' to ,drippings from enamelled articles which may be suspended within the furnace chamber 17 or be located therein supported by the floorT grating. l may provide an intermediate refractory 'column 23 or the column 23 may comprise a short vertical wall extending longitudinally yof the furnace chamber, the actual construction employed beingl entirely dependent upon the size and configuration of the furnace chamber. Heating elements of the kind hereinbefore described are located in' or againstthe vertical surfaces of the-wall'23.

ln order to reflect the heat generated by the heating elements located below the floor grating against the grating and against material located thereon or suspended thereabove, I provide one or. more refractory reand hold the bars 19,

Westinghouse fleeting surfaces of fiector members 24. The members 2a are built up ofa plurality of suitably shaped bricks or blocks of a refractory high-temperature'Y resistor material and the outer rethe members 24; should be relatively smooth. If the furnacechamber 1 6 is relatively small and substantially square in horizontal section, the. member 24e may be pyramidal in form and substantially squarein horizontal section. If one of the horizontal dimensions of the chamber 17 is much greater than the other, it may be necessary to employ Aan elongated member 24:, and a horizontal section therethrough will be substantially rectangular in form. In other words, the object of providing the members 24 is to permit of placing a plurality of electric heating elements below the material-supporting floor of the furnace chamber and of reflecting the heat generated therein against the under surfaces of materials to be heat treated, which' are suported on the floor grating or thereabove. hile I have shown a reflector having straight sides, I may employ reflector members having curved sides to effect any desired distribution of heat.

` It is apparent that fluid japan or vitreous enamel which may drip from the articles. to be heat treated or baked, during the initial stages of the heat treatment, would fall upon electric heating elements if they were to be placed in a horizontally-extending position beneath the floor grating, but this action is entirely obviated by locating the heating elements which are placed below the floor grating, in a substantially verticallyextendingposition and providing a reilectf ing surface which will reflect the heat generated 'thereby in an upwardly direction.

` The reflector members serve .also to prevent the respective heating elements located adjacent thereto from radiating heat to one another, thereby tending to reduce the temperature of the heating elements.

Various modifications and changes may be made herein without departing from the spirit and scope of my invention, and I desire, therefore, that only such limitations shall be placed thereon as are indicated in the appended claims or are imposed by the prior art. i

I claim as my invention:

l. In an electric furnace, in combination, a plurality of' refractory walls enclosing a furnace chamber, a working floor for said chamber, an electric heating element located below said working floor and means for refleeting the heat from said heating element upwardly against said door and against maa0 terial placed thereon.

2. In an electric furnace, in combination, side, top and bottom, refractory walls enclosing a furnace chamber, a workin@ lloor intermediate said top and bottom wa ls, an

Aelectric heating element located below said working floor in said side wall, and means for reflecting theheat from said heating element upwardly against said working floor.

In an electric furnace, in combination, a plurality of side, top .and bottom walls surrounding a furnace chamber, a plurality of radiant heating elements supported by one of said side walls in substantially vertical positions, said heaters being substanv tially coextensive with said wall, a working floor in said chamber located in a substantially horizontal plane intermediate saidv top and bottom walls, and means co-operating with the heaters located below, said working floor for-reflecting the heat generated thereby in an upwardly direction.

4. In an electric furnace in combination, a plurality of side, top and bottom walls enclosing a furnace chamber, a plurality of heatingelements located parallel and closely adjacent to and supported by each of said side walls, a plurality of heating elements located .in substantially vertical positions adjacent to and above said bottom wall 'and intermediate said side walls,a working floor extending between said 4side walls and above said intermediate heating elements, and means located between said side walls and said intermediate heating elements for reflecting the heat rays of said intermediate and certaiirof said side heating elements upwardly against said working lloor.

5. ln an electric furnace in combination, a plurality of side, top and bottom walls enclosing a furnace chamber, a plurality of heating elements located parallel and closely adjacent to and supported by each of said side walls, a plurality of heating elements located in substantially vertical positions adjacent to and above said floor and intermediate said side walls, a working floor extending between said side walls above said intermediate heating elements, and reflectors, of substantially pyramidal form for reflecting the heat of said intermediate and certain of said side heating elements upwardly against said working floor.

In testimony whereof, I have hereunto subscribed my name this twenty-third day of February 1923..

JULiUs D. Hai'NswoRTH.

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