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Publication numberUS868774 A
Publication typeGrant
Publication dateOct 22, 1907
Filing dateFeb 5, 1906
Priority dateFeb 5, 1906
Publication numberUS 868774 A, US 868774A, US-A-868774, US868774 A, US868774A
InventorsThomas R Goth
Original AssigneeThomas R Goth
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Dredging apparatus.
US 868774 A
Abstract  available in
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Claims  available in
Description  (OCR text may contain errors)



Specification of Letters Patent.

ratented Oct. 22, 1907.

Application lerl February 5, 1906. Serial No. 299,599.

To all 11i/zout it muy concern.'

Ilo it known that I, Tnouas It. Gorn, a citizen of the United States, residing at San lh'ancisco, in the county of San l `runcisco and State of (,lalifornia, have invented cert-1in new and useful Improvements in Dredging Apparatus, of which the following is a speciication.

This invention relates to the art of dredging and more particularly to dredging for gold or other valuable material wherever found. l, employ a rotary digger as an excavator, but in d stinction from the ordinary socalled suction dredfrers. I use a powerful stream of water having an inje tive action .for delivering the material through und from the dredging tube or pipo. I use a rotary snail-shaped cutter which excavatcs the material in con'ilrination with a hydraulic giant which elevates such material, and forces it through a discharge pipe to proper washing and separating apparatus. rlhere are many advantages pertaining to my construction, many of which are hereinafter stated; and these advantages result whether my dredger be compared with the ordinary so-callcd suction or hydraulic dredge, or with the chain bucket (,lredge commonly used in dredging for gold.

An embodiun-nt of my invention will be found in the accompanying drawings in connection with which this descriptr n should be read, and in which Figure l is a sectional elevation of the entire machine, Fig. 2 is a plan view with certain parts in horizontal section, lig, 3 isa plan view of the digging head, Fig. i shows a modified arrangement for driving a rot-.l ry (ligging head with a stationary inlet pipe.

At Ai is shown a suitable hull or scow for sustaining the dredging and washing machinery. At 2 is a rc` volving pipe sujmorted on rollers 3 journaled in the truss frame or ladder 4, which projects from the bow of the hull, said bow being open in pontoon fashion, so as to permit the convenient raising and lowering of the rotary pipe. `id pipe is rotated by gears 5 and (i which are connected into a system of gearing to be hereinafter described. Vlhe truss Vframe is supported from above in any suitable manner, and has proper tackle connected to the hoist or windlass 7.

On the lower end of the rotary pipe is the excavating head 8. This h( ad is secured rigidly to the pipe 2 and revolves with it. "lhis head is of snail shape and has a single projecting cutter S), and a single interior curved vane ll, which as the material. is cut forces it to the center of the digging head and up the rota-ry pipe. rl`he rotary pipe, at its upper end has an air tight bearing l2, in the elbow Iii, and in order that the excavator can be adjusted lo dig at any depth, such elbow is formed in two parts with a packed joint l-i between them. -rlhe statruiary part 13 of the elbow is connected to a discharge pipe l5.

The material is forced into and through the elbow and discharge pipe by thc powerful hydraulic giant 16 within the branch pipe o1' casing 17 which has a bearing upon it, and supplied by the centrifugal pump 1S. The rotary pipe, the movable part of the elbow and the branch pipe I7 form practically a T-shaped adjustable hydraulic mechanism, all ol which swing together as upon a hinge joint or trunnions when the digger is adjusted to cut at any angle of depth or of elevation.

A system of gearing for driving all parts of the machinery is shown in the drawing and although susceptible of modification, it is what I prefer to use, because in a simple way, it permits the adjustments required in effective dredging Without becoming deranged. I have shown as the primary power a motor 19, from which shaft a belt 20 drives a shaft 2l. A belt 22 from shaft 2l drives thc centrifugal pump I8. Another belt 23 from Ashaft 21 drives the shaft 24 which carries the miter gear 25. `Loose on the pipe or casing which surrounds the hydraulic giant is an intermediate gear 2G engaging with miter gear 25 and also with mi ter gear 27 on the shai t 28 which carries the spur gear 5 which as previously stated transmits the rotary motion to the pipe 2. The intermediate gear being loose on the pipe casing transmits power freely, no

matter what the adjustment of said casing, elbow, and

rotary pipe may be.

The material forced into and through the discharge pipe 15 is delivered into a revolving drum 29 having numerous perforations as shown. The drum is mounted on a shaft 3]. and is driven by a sprocket connection from the shaft 2l. Coarse material too large to pass the perforations in the drum is discharged upon the chute 32. Fine material, that is sand and small gravel in which all the gold is contained pass through the perforations upon the rif'llod surface 33. There may be a series of these riHed surfaces ii desired, and they may be provided with any of the well known gold saving means such as amalgamated plates. The water which passes through the perfor-ations in the drum is used upon the rifiles for washing and separating purposes.

The sand and Water on leaving the rifi'les discharge into a sump 3ft Where the sand settles to the bottom and is removed and discharged by the chain of buckets 35 which is driven by bevel gearing 36 from the drum shaft and sprocket gearing 30, as best shown in Fig. 2. The water collects naturally in the sump and overflows at its edge. l

At 37 is a gate valve which can be used to close the discharge pipe, so that if the rotary pipe should become clogged, all the power of the giant can be directed backwardly to Wash it clear.

This machine should be clearly distinguished from the ordinary so-called suction or hydraulic dredge. The latter is not successful in raising coarse gold, because it depends entirely upon the action of the centrifugal suction pump to raise all the material excavated by the cutter. Gold having about eight times the specific gravity of the material with which it is associated, the pump suction naturally draws the sand and gravel from underneath, allowing the gold itself to settle away from the entrance and be lost.

With the present invention the rotary shovel or head scoops up gold, sand, gravel rock, etc., as it revolves and deposits all such material mechanically within the rotary pipe, in which it is easily elevated by the hydraulic giant, and is afterward thoroughly washed and separated. The point of the shovel or digger is preferably made triangular so that any rock too large to be received by the single opening is forced to the edge and out of the way. lts motion through the ground also loosens any adherent particles of gold which are then scooped up, or sucked up by the action of the hydraulic giant.

It will be noted that the coarse material is delivered from the screen or drum at the rear and falls by gravity to the bottom of the hole in which the dredger is at work, while the sand and earth being elevated to a higher point falls upon and above such rock. rlhis requires no more power and leaves the country in condition for agricultural opera-tion again, while the bucket drcdger leaves the country around it a barren rock pile.

The material is more thoroughly broken up in its passage by the giant elevator, than can possibly be the case with a chain of buckets. This results in easier, quicker and better washing and separation.

As the inlet pipe revolves, the material cannot settle in the bottom and clog the opening, but is continually rolled over and over and ground up and separated by its own impact and that of the large stones or boulders which form a portion of it.

Other advantages might be enumerated, but it is believed that in view of the foregoing description they will be apparent to those skilled in the art.

I do not limit myself to the precise features of construction hereinbefore described and shown in the ac companying drawings, as I desire to avail myself of such `modifications and equivalents as fall properly within the spirit of my invention. For instance as shown in Fig. 4 the digging head might be connected to a station ary suction pipe and rotated by a sprocket chain, or in any equivalent way; but l prefer to use th o rotary suction pipe.

Having thus described my invention what l claim as new and desire to secure by Letters Patent, is1- l. In a dredger, a rotary snail-shell shaped digger or excavator.

2. In a dredger, a rotary snailshell shaped digger or excavator' having a single projecting cutting edge, and a singie inlet opening.

3. In a dredger, a rotary snail-shell shaped digger in combination with a rotary pipe to which said digger is rig idly secured.

4. In a dredger, a rotary snail-shell shaped digger having a single inlet opening in combination with a rotary pipe to which said digger is rigidly secured.

In a drcdger, a submerged or partially submerged pipe, and a rotary snail-shell shaped digger at the oxtrem ity or' said pipe, said digger having a single cutting odge and a single inlet openingl in its periphery.

G. ln a dredger, a submerged or partially submerged rotary pipe having at its extremity a snaibshaped rotary digger.

7. In a dredger, a submerged or partially submerged ro tary pipe having at its extremity a snail-shaped rotary scemi digger, said digger having a single projecting cutting edge, and a single inl opening.

S. In a dredgor, a substantially T shaped hydraulic connection, means for receivingspoil through the stem of the T, and a discharge passage for such spoil in one arm of the T.

l). ln a dredger, a substantially hinged T-shapod hydrauiic connection, means for receiving spoil through the stem of the T, and a. discharge passage l'or such spoil in one arm of the T.

10. ln a dredgor, a substantially T shaped hydraulic connection, a rotary digger at the extremity of the stem thereof, and a discharge passage through one arm of the T.

1l. ln a dredger a substantially T-shaped hydraulic connection comprising a rotary stem, arms connected thereto and hinged so as to permit the vertical adjustment ot' the stem, and :i rotary digger rigidly secured to the cxtremity of said rotary stem.

12. ln a dredger, a substantially T-shapcd hydraulic connection, the stom wheroii' has moans for receiving spoil, a discharge passage in one arm o1' the T for the discharge of said spoil and a hydraulic giant' in the other arm oif the T.

l). In a dredger, a substantially Tshaped hinged hydraulic connection, the stem whereof has means l'or receiving spoil, a discharge passage in one arm of the T for the discharge ot said spoil and a hydraulic giant in the other arm of the T.

14. ln a dredger, a substantially Tshaped hydraulic connection comprising a rotary stem, and two hinged arms connected thereto, a rotary (ligger at the extremity of said rotary siem, and a hydraulic giant in one arln of the T, whereby material excavated is drawn through said rotary stem and is forced through the other arm of the T.

l5. lu a drcdger a substantially T-shapcd hydraulic connection having hinge or trunnion bearings for its arms, a gear loose upon one of said arms, driving and transmitting gears in engagement with said loose gear, power connections to the driving gear, a stem for the T adapted to rotate, and means operated by the transmitting gear for rotating said stem; the construction and arrangement being such that the whole T connection can swing upon its hinge or trunnion bearings without deranging or affecting the operation of said gearing.

1G. In a drcdger means for separating the boulders and large matter from the liner matter and for discharging the boulders by gravity to the bottom of the waterl hole, a setllii sump at the stern of the dredger and below the level oi' said discharge, means for supplying tailings to said sump, and a chain ot' buckets or other suitable means for elevating tailings from said sump above said discharge; whereby said tailings arel deposited in the water hole above the boulders.

lT. ln a drcdger iiaying .means for separating coarse from [ine material a settling sump adapted to receive the tine tailings and a chain of buckets, or other suitable means for elevating said tailings from the sump and discharging thom i'rom a higher elevation than that at which tho coarse waste material is discharged.

18. In a dredger in which material is drawn and forced through and beyond an intake pipe by the action of a hydraulic giant, means ior freeing the intake pipe comprising a valve located beyond the giant and adapted to close the discharge pa ge; whereby the stream from the giant is forced backwardly through the intake pipe.

10. In a dredgcr, a rotary excavator, a substantially T- shaped hydraulic connection whose hollow stom carries said excavator, a hydraulic giant forming a trunnion bearing for one arm of the T, and a discharge pipe forming a trunnion bearing for the other arm ol the T. whereby the whole Tshaped connection can swing upon said bearings without affecting the action o'l the said giant or the discharge of material through the other arm ol` ihe T and said discharge pipe.

In testimony whereof l have allixed my signature. in presence of two witnesses, this 24th day of llanuary 1900.


Witnesses M. R. Sunni',

F. M. BAn'rnL.


Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3152409 *Jul 23, 1962Oct 13, 1964Pacific Coast Eng CoDredging equipment
US3438142 *Jun 7, 1965Apr 15, 1969Manfred G KruteinSea mining method and apparatus
US7005064 *Aug 16, 2004Feb 28, 2006Infrastructure AlternativesMethod and apparatus for remediating wastewater holding areas and the like
US20050016931 *Aug 16, 2004Jan 27, 2005Keller Robert A.Method and apparatus for remediating wastewater holding areas and the like
Cooperative ClassificationE02F3/9293