US1533264A - Electric-fubnace resistob - Google Patents

Description

A ril-14, 192s. 1,533,264

I; A. REID ELECTRIC FURNACE RES I STOR Filed DEC. 17, 1921 4 1 INVENTOR 7710/11 65/4. Pe/c/ A? F/yf WITNESSES: l9

Patented Apr. 14, 1925.

UNITED STATES PATENT DF 1,533,264,, FlCE-l THOMAS A. REJ ID, OF PITTSBURGH, PENNSYLVANIA, ASSIGNOR TO WESTINGHOUSE ELECTRIC do MANUFACTURING COMPANY, A Q PORATIQN O'F PENNSYLVANIA.

ELECTRIC-FURNACE RESISTOR.

- Ap lication filed December 17, 1921,

My invention relates toelectrically heated I apparatus and particularly to electric furnaces, and it has for its object to provide a relatively simple and inexpensive refractoryresistor mounting for an electric-resistance furnace which shall permit offsupporting a closely spaced resist or member in the fur-- nace chamber. j

In ractising my invention, I provide a plura ity of relatively narrow members, of

T-shnpe at their outer ends and of L-sha-pe at their inner ends, and means for loosely supporting spaced-apart sets of these members by the walls of the furnace I provide a relatively heavy preformed resistor member supported by the. inner ends of L shnpe of the refractory members and a single means for locking all of the refractory members of a setin-proper operative position after the resistor member has been properly mounted therein.

In the single sheet of drawings,

Figure 1 is a view, in vertical lateral cross section, of an electric furnace comprising a device embodying my invention, taken on the line I-'-I of Fig. 2;

Fig. 2 is a view, crosssection taken on the line ITII of Fl 1;

l igs. 3 and 4 are views, in front and in side elevation, respectively, of a refractoryresistor-supporting member and F ig. 5 is a top plan view of aportion of the means supporting the resistor-support-.

ing members.

ing a plurality of suitable supporting mem-' here 13. An outer lining.14 of suitable bricks or blocks of a refractory heat-insulating material is located insideof the frame in vertical longitudinal Serial No. 622,996.

The bricks .or blocks constituting the inner la 15 are spurned apart at suitable inter vals to provi e openings 17 'therebetween, the bricks immediately adjacent the open'-' ings 17 being provided with'shoulder per- 6Q tions for a purpose tobe hereinafter set forth. p '1. I A plurality ofirelatively narrow refri titor supporting members 18 are provided," one 1 having an outer end 'ofT-shape and an inner end of L-shepe; A portion 19, extend ing at right-angles to theimai'n body of the member 18, is provided 'with an ercuate lower edge portion for apurp'ose to be here inafter set forth; Theiwidth 'of the body} narrower than'the distance between the overi g s qu ls f Po io s e lth i k the inner lining 15 acljeeent the openings 17 to permit of'loosely mounting the supportingmembers 18 substantially in the posi tions illustrated in Fig 2. The. lateral width of the -portion 19 is slightly greater than the thickness :of; the resistor member whichit is to op 'eratively support. I I

A resistor member 21 comp rises a relatively heavy preformed rocl or bar having. a pluralityjof substantially I rellel-ex'tending and end-connected.'convo Minus, the dis tance bet-we en the individual and adjacent convolutions being substantially the sameas the distance between the adjacent refractory su porting members 18,

ie=meth d of mounting the: refractory supporting members and of the resistor member thereon willbe described more par-' ticularly with reference to the mounting. thereof in the roof of the furnace chamber. An opening 22 is provided in the outer lining 14 inthe roof of thefurnaceto permit (if-placing the members '18 in the proper operative positions in the respective openings 17, a plurality of suitably dimensioned. bricks 23-being provided to close'theopen ing 22 durin If desired, tl1e members 18 may be placed in their proper operative positions from the inside of the. furnace, the shoulder. portions hereinbefore described in connection with those bricks of the innerlining 15 adjacent P the openings 17 being cut ewayet one end of the furnace, as illustrated more particularlv in Fig. out the drawings, to permit of the outer ends of the members 18 being moved therethrqngh end then leterellyjof.

portion of eachof themembers'fi is slightly the'operetion of the fo 5. 19o

the furnace to their proper operative positions.

If it is assumed that the proper number of refractory supporting members 18 has been placed in position, substantially as illustrated in Fig. 1, the preformed resistor member 21 may be brought into operative engagement vcith the lower or outer faces of the inner ends of the members 18 and moved upavardly, thereby raising the members 18 or moving them longitudinall of their own lengths, the depth of the openings 17 being suflicient to permit-of this longitudinal movement. The right-hand convolutions of the resistor memberengagesthe lower arcuate surface of the .ortion 19 of the refractory member located immediate]; adjacent the wall .of the furnace and, by slightly moving this convolution to the leit, all of the refractory .resistorrsupporting members are momentarily moved to the left, permitting the mo'rementof the first convolution past the portion 19 audits location thereon to be supported thereby. The inheient resiliency of t-lie convolntions of the resistor member 21 permits of the successive movement of each convolution away from the preceding convolution to permit of its'moving along the arcnate surface ofthe portion 19 of the refractory supporting member with which it is to beoperatively associated until all of the convolutious-nre supported substantially as illustrated in-tlie top heating element of Fig. 1 of the drawings. The dimensions between theowalls, and. the number of refractory. supporting members 118. must be such thatthe distance between the cadet tlie por tion 19 of the last refractory member and the adjacent wall is at least equal to. if not slightly greater than, the thickness of the rod or bar constituting the resistor member 21. A key member .24 of substantially T-shape and made of any suitable refractory material may then be dropped into place through the opening 22. the key member being effective to maintain substantially all of the 1'efraetor imemhers 18 in proper operative positions relatively to each other and in the supporting means.

Substantially the same method of assemblj" may be followed in mounting the resistor, in the walls of the furnace, suitable openings 25' being provided adjacent the upper portions of the furnace, which openare located in lugs 'are normally closed by suitable bricks or blocks 26 during the operation of .the furnace. In order to space apart the outer ends of the refractory members when they the walls of'the furnace, may provide ,a plurality ofrefractory memhe'rs. 27 which arelocatedbetwcen the outer ends, of' the adjacent members, the (Union-- si'ons being substantially the same as the Length of. he overhanging portion 19.-

lieylmember fi inay'be provided to lock the I end of L-shap members 18 in the walls in proper operative positions relatively to each other. i

The device embodying, my invention permits of emplo 'ng a refractory resistor supportof a wi th'onl'y slightly greater than the thi lmcss of thebar of rod constituting the resistor'lncmbcr and, as the width of the body-portion of the member 18 may he made suflieient-ly large to provide the necessary strength, the thickness thereof may be made relatively small and .it is therefore. possible to so preform the resistor member. 21 that the distance between the successive and adj aeentconvolutions shall be relatively very small, which permits of locating a relatively large amount of resistance in a given surface area of the furnace chamber, thus permittin 0t raising the temperature of the furnace c iamber to'a relatively high value. The small. distance between the adjacent convolutionsofi'the resistor member also insures even distribution of heat'over an given area of the furnace chamber, whici is a highly desirable qualification in certain kinds of work'. 'The spaced-apart sets of refractory resistor-5n porting members engage a relatively sma port-ion only. of the length of each ofthe couvolutions of the resistor member which is made suflieientl' heavy in eross-section to .be substantially self-supporting,therebetween.

Various modificationsmay be made in the device embodyingmy 'nvention without departing from the irit and scope thereof,

. d I desire that on y'such limitations shall be placed thereon asja-re imposed by thev prior art or are specifically set forth 1n the appended claims.

T claim as my invention 1. In an electric furnace, in combination, a plurality of walls-spaced apart to form a furnace chamber, a resistor member of relatively large area 0.lateral cross-section in said chamber,- said resistor comprising a phu-ality of parallel-extending end-connected convolutions and a plurality of spaced apart sets of loosely mounted refractory resistor-supporting members and means for locking each ofsaid sets in operative position in said chamber.

' 2.'I'n an electric furnace, in combination, a plurality' of walls spaced apart to. form a furnace chamber,.a resistor member of relalively large area 'of lateral cross-section in said chamber, said resistor comprising a plurality of parallel-extending'and end eom ncctcd convolutions and a plurality of spaced refractory members having an outer e for supporting said resistor member, an inner end of T-shape to engage one of said walls and be supported thereby, and a sin le meansfor locking said refractory mom ers in their operative positions.

In an electric furnace, incombination, a

loo

plurality of walls'spaoed apart to form a furnace chamber, a resistor in said cham ber comprising a plurality of parallel-extending end-connected convolutions, and a plurality of sets of refractory supporting members, each having an outer end of substantially L-shape, said members being successively movable in the direction of their length to operatively engage and supportthe resistor members.

4.. In an electric furnace, in combination, a resistor member comprising a plurality of parallel-extending end-connected convolutions and a plurality of elongated refractory members, each having an outer end of L- shape, said members being first movable simultaneously in one direction longitudinally of their length and then movable successively in the opposite direction to operatively engage and support the resistor member.

5. In an electric furnace, in combination. a resistor member comprising a'plurality of parallel-extcnding end-connected convolutions and a plurality of elongated re tractor} members, each having an outer end of L-s'hape, said members being first.

movable simultaneously in one direction longitudinally of their length and then morable successively in the opposite direction to operatively engage and support the resistor membelyand means for locking all or said refractory supporting members in their operative positions.

6. In an electric furnace, in combination, a resistor member comprising a plurality of paralle1-extending end-connected convolutions of relatively large-area in lateral crosssection, a plurality of relatively narrow elongated refractory resistor-supporting members, the outer end of each being substantially of L-shape, said refractory members being first movable simultaneously longitudinally away fromtheir normal operative positions and then movable individually and successively back to their normal operative positions to engage and supportthe resistor member over only short portions of its length, the said resistor member-being said. supporting 5o self-supporting between members.

7. A. resistor-sup oorting means comprising a plurality o contiguous refractory members, each having one end of L-shapefor engaging and supporting-a resistor member and means for loosely supporting said refractory members. i

8. A resistor-supporting means comprising a plurality of contiguous refractory members, each having one -e'n'd of. L-shape for enga ing and supportinga resistor member, and having the other end of T'-sba-pe, and means for so supporting said refractory members as to permit of limited movement thereof'in adirect-ion longitudinally of their length. 1 I r Intestimony whereof, I have hereunto subscribed my name this 29th day of November, 1921.

'IHQA'IAS A. Run

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