US1584277A - Gold dredge - Google Patents

Description

May 11 1926.

J. S. DEC

GOLD DREDGE Filed Feb. 5, 1925 ATTORNEYS Patented May l1, i926.

UNITED STATES JOSEPH STANLEY Dnc, or,vAricoUvnR,` Barrrsrr COLUMBIA, CANADA.

GOLD DREDGE.

Application sled February 5, 1925 serial N10. raies.

My invention relates to improvementsin gold dredges the objects of which are to provide means whereby gravel may bedredged and passed over a sluice box to recover precious metals therefrom in a single operation and to deposit the sluiced gravel at the rear of the dredge bucket without raising it from the water.

The invention consists essentially of a pontoon having a bucket which is Vadapted to be lowered to the bed of the stream, in which bucket a sluice box is provided and means for raking the gravel dredged to deposit its precious metal contents into the sluice box, as will be more fully described in the following specification in which Fig. 1 is a side view of the dredge. Fig. 2 is a plan view of the dredge. VFig. 3 is a plan view 'of the bucket and sluice box.

. Fig. 4 is a sectional view of same.

In the drawings like characters of reference indicate corresponding parts in each figure.

The numeral 1 indicates a pontoon having a longitudinal recess 2 in its forward end to permit the dredge arms and bucket to be lowered and raised. A transverse frame 3 is mounted upon the rear of the pontoon upon which a countershaft A4 is provided having a driven sprocket 5 at one end and a drive sprocket 6 intermediate its length. The shaft 4 is driven by an engine 7 or any other suitable means. Extending fro-m the shaft' and rockingly mounted thereon is a pair of arms 8 which are pivotally connected to the rear end of the bucket as at 9'.

The numeral 10 indicates a further pair of arms which are pivotally connected to the forward end of the bucket as at 11 and are slotted at their upper ends as at 12. such slotted portions being adapted to fulcrum upon a transverse rod 13 in the frame 3 and 5 are apertured throughout their length for the reception of pins 14 by which the arms 10 are held against longitudinal movement yet may be adjusted as required to tilt the bucket up or down to conform to irregularities in the level of the stream bed. The

bucket, generally indicated by the numeral 15 (see Figures 3 and 4) is provided with a bottom wall 16, side walls 17, the forward edge of the bottom wall is provided with a shoe 18 which enters the gravel of the stream bed at a suitable distance below its surface. Extending rearwardly vfrom the* front of the shoe is a plurality of strips of` metal 19 forming yan incline up which the gravel and rocks have to pass. y

The numeral 2() indicates a sluicevv `box which is provided with transverse rifiles 21";

and is covered over with a wire mesh 22 of suitable size to pass any precious metal and to exclude gravel and rock.- f

Mounted between theside walls 17 of the bucket'is a pair of transverse shafts 23 which serve as fulcrums for the arms 18 and 10 and upon which chain sprockets 24 and 25 are secured. A chain 26 is used to drive the sprocket 25 of the rear shaft 23 of the bucket, from the sprocket 6 of' the counter` shaft 4,' and a pair of parallel chains 27'- couple opposing pairs of sprockets 24. Between vthe chains 27 transverse rods 28 are mounted at intervals which are each 'provided' with prongs 29 .to serve as rakes for the purpose of passing the gravel entered by the shoe 18 lengthwise of the bucket and the sluice box 20 to screen the precious metal thereinto and to discharge the screened gravel to the bed of the stream.

The numeral 30 indicates a line secured at one end to the bucket 15 and leading to a winch 31 on the river bank or in any other suitable position by which the bucket is drawn forward to enter the bed of the stream.

The numeral 32 indicates a frame mount.- ed upon the'forward end of the pontoon 1 upon which is carried a pair `of'windlasses 33 and 34 respectively,r from. the windlass 33 a line 35 is taken to a suitable winch or anchorage forward of the dredge that it may be drawn theretov as the `dredging and sluicing proceeds, and from the windlass 34 a line 36 is carried which is connected to the bucket for the purpose of raising it from,

the bed of the stream and also to limit the depth of its cut thereinto.

Having thus described the several parts of my invention I will now briey explain its use.

The dredge is floated into position against the current and anchoredby the line 35, the bucket 15 is then lowered to the bed of the stream and the engine 7 started to operate the raking mechanism. The dredge is slowly drawn forward by the line 30 to cause the shoe 18 to enter the stream bedand to deliver the gravel under the raking prongs 29 which pass it over the screen 22 and separate lthe metal and sand therefrom, which falls into the sluice boX 20.

Should the stream bed be sloping at the approach of the river bank, the bucket is adjusted "to correspond by 'altering'the position of engagement of the forked ends l2 of.

, the arms with the transverse shaft 13.

In order to overcome-the -tendencyfof the current to float the pontoon rearwards and ito cause the bucket to lift fout-of contact n with the :stream bed, the line .35 ais ftensioned `by the windla-ss 33 luntil :the rbueket is properly seated, when simultaneous hauling ,is eected on `both lines and .30 to main- 'tain the Lbucket at the Ypi-oper depth 'during dredging -,ends fof said arms,l a `dredge .bucket ,pro-

vided at .one end with ybea-rings `receiving said .shaft therethrough, :a second shaft mounted -in tbearings -at the Yopposite ends orf said bucket, a second pair of supportling arms having their lower ends attached to said second shaft and their upper ends mounted on the float for pivotal and sliding movement, an endlessrake carried by said shafts, a screenedI receptacle cariied'by the bucket beneath said rake, means .for ,guiding material on to the screened portion of the receptacle, and means for actuating the rake shafts.

2. A dredge comprising a ioat, a dredge bucket, a pair of supporting arms having their lower ends pivotally att-ached to the dredge bucket .near one vvend thereof and their upper yends Ypivotally and slidably secured to a superstructure mounted on the float, a second pair of supporting `arms paralleling the arms of the .firstpair and located below tthe same, the arms -of vsaid second pair being pivoted `at one end .to ythe dredge `bucket and at the `opposite 4end to vthe aforesaid superstructure on the float, `said Afirst `mentioned arms being slidably adjust-able with reference 'to the `superstructure .to cause .the Adredge bucket to assume various angular positions.

Dated .at Vancouver, B. C., ,this :28th day of January, 1925,.

JOSEPH STANLEY DEC.

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