US612706A - Samuel crow - Google Patents

Description

No. 6I2,706. Patented Oct. I8, |398. S. CROW. CUMBINATIUN DHEDGE FOR MINING FOR AND SAVING GOLD, TIN, AND DTHER METALS.

, (Ap'plicadgion ld Aug. 4, 188.7. N o M o d e I ma Norms ravens co, noauwo., WASHINGTON. o, c.

countant, a subjeetor :the Queen of Great Britain, residing at 31 Moray Place, in the f1., ing Gold,Tin, orA other Metals, of which the .Y at a higher level than the bottom of the padtoons or by means ofV jib-cranes or the like.

SAMUEL cEow, or DUNEDIN, NEw ZEALAND.

COMBINATION-uriner FoRwNlNe For AN D SAvlNe GOLD, uN4J 0R OTHER METALS.

S'PEQIFICATION forming part of Letters Patent No. 612,706, dated October y18, 1898.

Application filed August 4L, 1897. i

To afZZ wwiiz it 77mg concern: i

ille-it known that I, SAMUEL CROW, an ac city of Dunedin, in the British Colony of New Zealand have invented a new and useful Combination-DredgeV for Mining for and Savfollowing is a specification.

The object of this invention is to mine and treat an alluvial paddock and to clean up the bottom of samein order to obtain the gold, tin, orther metals in theWash-dirt, crevices, and bottom. A

A dredge is made in the usual Way for bucket-dredging and is also provided with sand-pumps. Vhen dredging With buckets, the largest of `these pumps `is usedfor elevating the tailings and the rest for lifting the Water or wash-dirt. f The following is a general description of the :manner in Which I eiiect my working:V

A paddock is dredged to as near the bottom as possible, and part or a space beyond the paddock is cut to a sufficient depth and size to containthe dredge when the paddock is pumped out, sothat the dredge is retained dock. y.

During the dredging of the paddock the tailingsepipe will sometimes have to be of a" great length to clear the edges of the paddock. This pipe Will either be supported on pon- Dams may have to be formedv when in or near a body of waterto allow of the subsequent draining of the paddock. lVhen the paddock is drained or pumped out, it is sluieed by nozzles with Water supplied from a well in the dredge or other available source to the suction of one ofthe sand-pump s,which discharges the wash-dirt thus obtained into .l a perforated revolving screen furnished with holes of graded size,l the smaller holes being at the upper4 end of the screen. Vhen the buckets are being used for lifting, the washi dirt is delivered into`thissame screen. The Wash-dirt so delivered into the upper end of the screen is separated thus: The portions too coarse for passing through any of the `holes in the screen pass over a coarse grid, and then the very coarse pieces go overboard i Serial No. 647,091. (No model.)

andthe rest drop into aboX, while the graded portion which Ahas passed throughthe holes in the screen spreads over savingtables,pref

erably covered with ripples of expanded metal, and then drops into a Well. This washdirt is then elevated into adistrib'uting-box,

where it is 'again spread over tables and return-tables to save deck-space. Any of the tables may be provided with se1f-cleansing traveling 1n atting's, so as to present a cleansed surface to the descending Wash-dirt. From these tables the wash-dirt passes to the tailrace, which leads it past the `well at the foot of the iirst tables under the screen, so that when' desired the wash-dirt can be turned again into this'Well, and the saving process can thus be repeated, or else the Wash-dirt is allowed to pass to the tailings pump or elevator. j' l W'ater for washing down the tables is drawn in by one of the pumps arranged for this Work, and a branch from the pump suction-pipe drains the well when required, or. the Well may be allowed to overflow to the tailingspu1np,which is obviously the largest one.

When the bottom of the pumped-out paddock is being cleaned up, the buckets are not in use,V and as the ,dredge may then for convenience sake have been grounded the usual Iplacc of intlowforcirculating water to cool fthe condenser ywould be ineffective, and so to furnish this Water a connection may be taken from the well inside the dredge.

Any of the'boxes, tables, or tail-race may be furnished lwith such suitable saving appliances as are usually used.

Referring to the accompanyingdrawings, Figure lis a plan of a dredge-With the apparatus as arranged for my manner of working. Fig. 2 is a part elevation and part section of same with the sides of` the tables and boxes removed to show same' better.

A A is the punt or hull of any dredge, and A is the bucket-well forf the line of buckets to Work in for dredging. y

' B is the position of the usual line of dredging-buckets in a bucket-dredge, and B' is the main upper tumbler.l f`

C is any condenser as used for compound engin es and is shown merely to illustrate the arrangements for the water circulation under the conditions in `which the dredgelmay be.

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\ D is the main intakeor suction pipe of the wash-dirt and water pump D. The discharge is usually through the pipe D to the pipe F in the cylinder E. The pipe F is perforated -with fine holes in that part which is inside the cylinder E and is used when water is pumped by D for washing the wash-dirt brought by the buckets B when they are Working; but it is changed for a plain pipe (also F) simply discharging from the upper end when the pump D is delivering wash-dirt and water and the bucketsB are thrown out of gear.

E is a revolving perforated screen usually running on small rollers, as shown, and set at an angle for free delivery, at the lower end, 'of the wash-dirt that cannot be screened.

This screen is slowly revolved, usually by tooth wheels, as shown. The supportingwheels may, however, be larger and flanged, as railway-\vheels, and the power can then be applied to some of these wheels to cause the cylinder to revolve slowly, the flanges merely preventing the tendency of the screen to slide down during its revolutions. This cylinder is perforated with graded holes between vthe roller-paths, the smallest perforations being at e, the holes becoming larger in the direction of e and being largest at e.

ered by the buckets B, in which case the water for washing same is delivered by the pump D into the perforated pipe F and through the delivered at the top of the plain pipe F by the pump D', the wash-dirt is screened through the graded holes in the screen E, and the combined wash-dirt and water for washing pass together over the tables G to the well H H. Any wash-dirt too coarse to go through the screen-holes passes over the bar-grid Lwhich separates it, so that the iiner wash-dirt drops into the box J, the coarser sliding overboard on the plate I, thus avoiding the choking of the pump K. As the well H H would soon be full of wash-dirt and especially of water, the surplus Water may be drawn off by the pipe G'. The amount so drawn off can be regulated by a stop cock in the pipe G. Should it be found desirable, the whole of the water can be sent over the tables through the pump D by way of the screen E, or part or all may be allowed to escape through the opening S to the tail -race R' vand so to the tailingsdischarge pump K by the pipe K. The wash-dirt in the well H H gravitates to the foot of the elevator L, which takes it to the distributing box M, together with the small quantity of water which may have been well A -or from the well H, if the supply from g A fails, by the pump L" and is supplied through the perfor-ations of the pipe L'. The

Wash-dirt then passes over the saving-tables N, and it will be seen that in this operation the desired quantity of water can be used and there is no compulsion touse the larger quantity of water that is required for screening, which larger quantity would tend to prevent the lodgment and saving of the gold, tin, or other metals. From N the wash-dirt passes to the box O and to the under tables P, on

. which the matting slowly travels in a direction contrary to the flow of the wash-dirt.

IThis matting is constructed as an endless band having the lower part moving in a trough of water,where it can be brushed by a revolving brush Q to remove the concentrates collected on the matting, thus enabling the` mattn g to present a cleansed surface to thewashdirt coming from the box O. Passing through the-box R to the tail-race R the Wash-dirt can, if desired, at any time be directed through ythe opening or by-wash S, and thus returned to the well H to be re-treated over the tables N and P. Otherwise the wash-dirt passes to J, where it is pumped by the pump K' to the tailings through the pipe K. When it is desired to repass any of the wash-dirt through any of the processes, the dredging can be stopped, or partly so, by the buckets or pumps j being stopped or slowed. In working whether the wash-dirt is delivj- When the dredge is used as a bucket-dredge to cut the paddock out, the pumps Dl and K' are used. The pump L" is used when the enigines are running; but if the watery is not ,required to pass over the table N it can be turned overboard by any branch. (Not shown.)

lf at any time it is found that the buckets cannot reach low enough in the paddock then f being worked, a suitable depth can be obtained by reducing the inflow of water to the paddock. Then the discharge-pump from K Will reduce the Water and give the depth required. The part dredged outside and adjoining the paddock on which the dredge is Vto be iioated to and secured must only be of suinpumps to work effectively. For the purpose of pumping the paddock after excavation by the dredge all the pumps can be used. The water pumped by the pump D' will be turned into K by opening the valve in the pipe G", the pump K will draw throughthe branch T on opening the valve in branch T and placing a blind flange on the end of the pipe in the box J., and the pump L" will draw through the branch U, generally used for sluicing, by closing the Valve in the pipe G' and also closing the end of the pipe that is under the tables G by a blind flange. The pipes D, K, and T may be swiveled in any direction to suit circumstances. In subsequently cleaning the bottom the well H is supplied with water, T is stopped, and for sluicing water is allowed to fall bygravitation from U. Washdirt is drawn in at D, passing to the screen and other saving processes as described, the tailings passing away at K.

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In this invention any suitable materials,

sizes, or grades may he adopted.

What I claim as my invention, and desire to obtain by Letters Patent of the United States, is-

1. In a combined dredge and ore-concentrator, the combination of a boat, means for elevating the material operated upon supported on said boat, a graded screen into which said dredge discharges, a Water-pipe discharging into said screen, separating-tables located underneath said screen, a we into which `Said tables discharge, an elevat` in said Well, a separatingtable upon which. said elevator discharges, an endless apron provided with matting upon which said table discharges and discharge-troughs whereby the tailings may be delivered either to the tailings-pump or to the well, substantially as described.

2. In a combined dredge and ore-concen-V trator, the combination of a boat, a dredge supported on said boat, a graded screen into which said dredge discharges, a Water-pipe discharging into said screen, separating-tables underneath said screen, a Well into which said tables discharge, means for removing the surplus Water from said Well, an elevator in said Well, a separating-table into which said elevator discharges, an endless apron provided With matting upon which said table discharges, a revolving brush for cleanin g said atting, and discharge-troughs, whereby the ailin gs may be led directly to the tailingspnmp or back to the Well for retreatment, substantially as described.

SAMUEL CRUWV.

W'itnesses:

I-IENTON MfrcAUL-AY DAvEv, CHARLES EDWIN DAvEY.

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