US2045073A - Aluminum furnace - Google Patents

Description

June 23, 1936. H. ELDRIDGE ALUMINUM FURNACE Filed Sept. 23, 1953 2 Sheets-Sheet l 0 itii hl will I N VN TOR. 17/1 4/02 Y Liv/P1061: Diet/I550.

flaw/2 9 4 5444 4 June 23, 1936. ELDRlDGE 2,045,073

ALUMINUM FURNACE Filed Sept. 25, 1953 2 Sheets-Sheet 2 INVENTOR. fizz/02 EDE/D65DECEH5ED.

. Patented June 23, 1936 ALUMINUM FURNACE Hilliary Eldridge, deceased, late of Oakland, Calii'., by Martha K. Eldridge, Oakland, Calif.,

administratrix Application September 23, 1933, Serial No. 690,675 7 Claims. (Cl. 204-20) The present invention relates to improvements in aluminum furnaces particularly adapted for producing aluminum by electrolizing bauxite ores, or the like.

with an annular groove l4 formed in the lower face of the bottom of the furnace casing I5, the latter being provided with an outwardly projecting annular flange IS, the function of which will become apparent as the description proceeds.

One of the objects of the improvements'is the 5 provision of a furnace whereby aluminum can In the grooves |3, M are disposed bearing bails be economically produced from aluminum oxide ll, which are adapted for rolling along in said or bauxite, or the like. grooves upon the rotation of the casing |5 dur- With the foregoing and further objects and ing the operation of the furnace. Obviously, any

purposes in view which will appear as the desuitable number of bearing balls maybe employed. 10

scription proceeds, the present invention resides A centrally disposed opening I8, having an upin the combination and arrangement of parts wardly projecting annular flange I9, is formed and in the details of construction hereinafter dein the bottom of the casing l5, and to the botscribed and claimed, it being understood that tom face of said casing, encircling the opening 5 changes in the precise embodiment of the inven- I8, is fixedly secured the gear ring 20, which is tion herein disclosed can be made within the provided with downwardly projecting gear teeth scope of what is claimed without departing from in mesh with the teeth of a gear 2| fixedly sethe spirit of the invention. cured to one end of a shaft 22 rotatably mounted In the accompanying drawings in bearings 9 supported by the supports 8. The

Figure 1 is an axial vertical section of the presarrangement being such that the rotation of the 20 ent improved furnace; shaft 22 will cause rotation of the gear ring 20 Figure 2 is a median vertical sectional view of and casing IS on the bearing balls I1. parts forming the connection between one of the The casing I5 is lined on its inner sides with electrode elements and its supporting standards; a lining of fire-brick 23, on the top of which Figure 3 is a top plan view of the graphite lining and overlying the flange I6 is disposed a 5 block; flat insulating ring 24, which is preferably formed Figure 4 is a top plan view of the supporting of asbestos, mica, or the like. table; Projecting downwards into the casing l5, but

Figure 5 is a top plan view of the graphite spaced a'suitable distance from the lining 23,

crucible; is a cylindrical core-supporting crucible 25, which 30 Figure 6 is a view in elevation of the contact has a flat bottom 26 provided with a centrally brush element and parts associated therewith; disposed opening 26' in axial alignment with the Figure 7 is a bottom plan view of the furnace opening l8. The upper rim of the crucible 25 has casing and gear ring secured thereto; an outwardly projecting annular flange 21 pro- Figure 8 shows top plan views of the cover vided at its outer edge with an upstanding an- 35 plates in their relative operative position; and nular contact flange 28.

Figure 9 is an axial sectional view of parts The crucible 25 is supported by means of its associated with the contact brush element, with flange 21 seated on the insulating ring 24, the latportions shown in elevation. V ter being intended to form electrical insulation Referring to the drawings in detail, throughbetween the pct 24 and easing I5. 40 out which like reference characters designate like In the crucible 24 snugly fits a graphite core parts: a 29, which has an annular ore chamber 30, a cen- The numeral designates the base plate, to tral recess 3|, a pair of vertically extending openwhich is fixedly secured a principal standard 2 ings 32 intermediate said ore chamber and recess,

pporting an electrode element 3, a complemena pair of opposed horizontally extending open- 45 tary standard 4 supporting an ore-feeding eleings 33 connecting the lower ends of the openings ment 5 and a contact brush element 6, a fur- 32 with lower portions of the ore chamber 30, and nace-supporting table I, and shaft-supporting a pair of horizontally extending openings 34 consupports 8. necting intermediate portions of the recess 3| The furnace-supporting table 1 comprises a with mid portions of the openings 32. The open- 50 ring like member I0 supported by legs II, the ings 32, 33 and 34 are intended to permit fluid or latter preferably fixedly secured to the base semi-fluid material to flow from the chamber 30 by means of screws l2. to the recess 3|.

The upper face of the member I0 is provided A cover, preferably formed of cast iron, and

with an annular groove l3 registering vertically comprising a ring-like outer plate 35, and a cy- 55 lindrical inner plate 36, are disposed to seat on the flange 21 and core 29. The relative dimensions and disposition of the plates 35 and 36 are such as to provide an annular channel 31 therebetween in central registration with the annular ore chamber 30. The plate 36 has a centrally disposed annular flange 38 fitting snugly into the recess 3|, whereby lateral movement thereof is intended to be prevented. The plate 35 may, if desired, be secured to the flange 21 by means of bolts or screws, not shown.

In the opening 26' is threadedly secured the upper end of a vertical pipe 39, which is lined on the inner side with a discharge tube 40 preferably formed of refractory material.

If desired, openings (not shown) may be formed to extend through the casing I and fire-brick 23, to provide for the escape of air or gases formed or accumulated in the space intermediate the pct 26 and the lining '23. Also, if found desirable, openings (not shown) may be formed in the cover plate 36 intersecting with the recess 3| and openings32 for the escape of air or gas accumulating therein.

The electrode-supporting element 3, which may be of any suitable construction, and which is preferably electrically insulated relative to the standard 2, as best shown 'in Fig. 2, by means of a gasket H, and sleeves 42, supports a depending carbon electrode 43, which projects downwardly through the annular channel 31 a distance into the annular ore chamber 30.

The ore-feeding element 5 comprises a hopper 44, a body portion 45, in which is rotatably mounted a feed-screw 46, and a delivery nozzle 41, the free end of the latter being disposed directly above the channel 31, whereby ore fed through the orefeeding element will be deposited in the annular ore chamber 30 through the channel 31. The feedscrew 46 is connected to the shaft 22 by means of pulleys 64, 65 and a belt 53. The contact brush element 6 embodies a frame 5| preferably formed en bloc with the upper end of the standard 4 and having an upwardly projecting exteriorly threaded boss 52 having a central vertical opening 520., the boss threadedly engaged by an interiorly threaded cap 53, a guide bushing 55 formed of electric insulation material, a washer 56 also of insulation material, and a transmitting-stem 51, which has its lower end forked for rotatably supporting a grooved roller brush 58, the transmitting-stem projecting longitudinally slidably through the bushing 55, cap 53 and the washer 56 and is provided at its upper end with nuts 59 for securing thereto the electric circuit wire 60.

The brush 58 is adapted to operatively roll along on the annular contact flange 28, and to make electric contact therewith during the operative rotation of the furnace body.

An extensile coil spring 1|, encircling the stem 51, is confined against the resilient tension of itself between the lower forked end of the stem 51 and the bushing 55 for maintaining proper electric contact between the brush 58 and flange 28.

The element 3 is intended to provide electrical connection between the electrode 43 and circuit wire 6|, which, in association with the wire 68, forms the electrical connection between the present furnace and the source of electrical supply. The element 3 forms preferably the positive, and the element 8 the negative, terminal of the circuit.

The shaft 22, which may be operated by means of the pulley 62 connected to a power plant (not shown), rotates the furnace body by means of the gear 2| and gear ring 28, as well as the feeds screw 46 through the medium of the belt 63 operating over the pulleys 64, 65.

A gas stove comprising an intake pipe 66, supporting legs 61, and cylindrical head 68 having a central vertical opening 69 through which the 5 pipe 39 projects, is provided for maintaining the desired temperature of the furnace body as well as the pipev 39, whereby the fluidity of the decomposed ore mass may be maintained forpassing from the ore chamber 30 to the discharge end of the pipe 39.

In operation, after heating the furnace to a proper degree by means of the gas stove, the shaft 22 is rotated through the medium of the pulley 62, causing the furnace body to rotate on the table 1, and the feed-screw 46 to rotate in the feedelement 5 and to propel the granulated bauxite deposited in the hopper 44 from the latter to the nozzle 41 and through said nozzle to the ore chamber 30. After a sufficient amount of the bauxite granulations (10) has been scattered along in the rotating ore chamber 30, to be properly engaged by the electrode 43, an electric connection is set up extending from the source of electric supply to and through the element 3, electrode 43, bauxite ore in the chamber 30, graphite core 29, pct

to the flange 28 and brush 58, and from the latter through the stem 51 to the return current wire 68. After the decomposition of the ore by means of the electric current, the fluid bauxite, or mass, passes from the chamber to the recess 3| and thence out through the pipe 39, after which it may be separated by proper means into its several component parts.

If desired, a carbon block may be substituted for the graphite core 29.

Obviously, a plurality of-thermometers and/or pyrometers may be projected into the recess 3| and the air space between the lining 23 and pot 25, to determine the degree of heat set up therein by the decomposition of the bauxite ore and heat irairnished by the gas stove through the opening What is claimed, is:

1. In an aluminum furnace of the character 46 described, a furnace body provided with a refracttory core having a centralrecess formed in its upper face, and having an annular ore chamber encircling said recess and-having a plurality of openings formed in said core for connecting said recess with said chamber.

2. In an aluminum furnace of the character described, a base, a furnace body rotatably supported by said base, said furnace body including a core-supporting crucible, a graphite core fitted 5 inside said crucible and having a centrally disposed recess formed in its top surface and having an annular ore chamber encircling said recess, an anode electrode supported by said base, and projecting into said ore chamber, and a con- 90 tact brush in electrical contact with said crucible, said crucible and said graphite c'ore forming portions of an electric circuit of which said electrode and said brush form portions.

3. In an aluminum furnace of the character described, the combination with a body portion comprising a rotatably supported furnace casing open at its upper end and lined on its inner surface with refractory material, of a core-supporting crucible projecting downwards into said body 70 portion and electrically insulatedly supported by the upper rim portion of said body portion, said crucible being spaced from said refractory material whereby an air space 'is formed therebetween, said crucible containing a graphite core provided with an ore chamber, means for conducting molten aluminum from said crucible downwards through said air space and body portion, and means forrotatably supporting said' body portion.

4. In an aluminum furnace of the character described, an ore-smelting crucible having its upper rim provided with an upstanding annular flange, and a wheel to roll on said flange, said wheel adapted to provide electrical contact be-' tween said crucible and a source of electrical power.

5. A furnace casing lined on its inner surface with refractory material, an ore-smelting crucible supported within said casing whereby air space is provided between said crucible and said refractory material, and a core of refractory material disposed in said crucible, said core provided with an annular ore chamber.

6. A graphite core having an annular ore chamber formed in its upper face side, said core having a centrally disposed recess and an opening or duct extending from said recess to said ore chamber.

'7. An ore-smelting crucible in which is disposed a core of refractory material, said core having a centrally disposed recess formed in its upper face side and an annular ore chamber encircling said recess and a plurality of openings connecting said recess and ore chamber together, and a cover disposed above said core, said cover having an annular opening or slot registering vertically with said ore chamber.

. MARTHA K. ELDRIDGE, Administratrix of the Estate of Hilliary Eldridge.

Deceased.

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