US801968A - Gold-saving apparatus. - Google Patents
Gold-saving apparatus. Download PDFInfo
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- US801968A US801968A US21904104A US1904219041A US801968A US 801968 A US801968 A US 801968A US 21904104 A US21904104 A US 21904104A US 1904219041 A US1904219041 A US 1904219041A US 801968 A US801968 A US 801968A
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- US
- United States
- Prior art keywords
- screen
- grizzly
- gold
- tables
- sluice
- Prior art date
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B03—SEPARATION OF SOLID MATERIALS USING LIQUIDS OR USING PNEUMATIC TABLES OR JIGS; MAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
- B03B—SEPARATING SOLID MATERIALS USING LIQUIDS OR USING PNEUMATIC TABLES OR JIGS
- B03B7/00—Combinations of wet processes or apparatus with other processes or apparatus, e.g. for dressing ores or garbage
Definitions
- My invention relates to improvements in gold-saving apparatus for use particularly in hydraulic and other placer mines.
- FIG. 1 is a side elevation, partly in section, of my invention.
- Fig. Q is a section of a portion of a table, showing screen-frame and locking means therefor.
- Fig. 3 is a side elevation of same.
- Fig. 4 is a plan view of a sluice and a set of tables.
- Fig. 5 is a longitudinal section of sluice, showing operatinglevers for grizzly-gate.
- Fig. 6 is a side elevation, partly in section, of table and vibrating screen.
- Fig. 7 is across-section of same.
- A represents a sluice-box carrying the rocks, boulders, and earth just as they come from the mine under the impetus of perhaps several hundred inches of water.
- a grizzly or grating 2 Interposed in the bottom of this sluice is a grizzly or grating 2, comprising a series of parallel-spaced iron bars extending lengthwise of the sluice, through which the sands, gravels, and material less than a certain size, together with some water, are discharged into suitable hoppers 3 and directed thence to opposite sides upon the aprons 4 and from there upon the tables 5.
- I provide a hinged grating 6, pendent beneath a section of the grizzly and adapted to be folded up in the direction of the current-flow to close the interspaces of the grizzly.
- This grating or closure 6 is preferably formed of iron or steel bars, substantially A-shaped in cross-section and staggering with the bars of the grizzly. It may be operated by any suitable means, as the levers 7 and links, rods, or chains 8, connecting with the free end of the grating.
- the levers are fulcrumed above sluice A, and the rods 8 pass down through the grizzly near the side of the sluice-box.
- the closure is held in lifted position by any retaining means-as, for instance, the hook 9, engaging lever 7.
- Each section of the grizzly might be provided with a similar closure.
- the tables 5 may be of any number. Preferably they are in series, as here shown, one above the other, oppositely inclined and each adjustable vertically in suitable guides in a framework 10.
- the tables may be of any length or width and are divided longitudinally into a plurality of sluices or runways by shallow partitions 14.
- the surface of a table is riffled or covered with canvas, as shownat 15, Fig. 2, and over this canvas is stretched metal screening or fine wire-netting 16, which has been found to possess the quality of retarding the velocity of the undercurrent and to assist materially the separation of the sands and values from the gangue and coarse barren matter.
- metal screening or fine wire-netting 16 which has been found to possess the quality of retarding the velocity of the undercurrent and to assist materially the separation of the sands and values from the gangue and coarse barren matter.
- the screen be secured on all sides. When a clean-up is necessary, the screen is taken up and the canvas swept and washed off.
- the screen is arranged in sections of a width equal to that approximately of the concentrating-surface between the partition 14 and of such length easily to be handled. I have found that two and ahalf or three feet is a good length for these sections.
- Each section is framed in a metal frame and each frame is adapted to be removably locked in its place on the table.
- These screenframes comprise two lower side plates 17 and two upper side plates 18, between which two IIO opposite edges of a screen-section are bolted.
- the plates 18 have each an inside drop portion 19 overhanging the inner edge of its respective plate 17 and adapted to bring the screen flush with the under side of the plates 17, so that the screen will lie fiat on the canvas.
- the upstream and downstream edges of the screen are bolted to the under side of the thin cross-plates 20, which are suitably secured to the plates 18.
- a screen-section is quickly taken out of its frame by removing the plates 17 and unbolting the screen from the cross-plates 20. rIhe frames are laid on the canvas one after another and are removably held in position by suitable means, as the locking devices 21, which consist of levers fulcrumed in the parts 14, adapted when vertical to press on the sides of the frames and prevent any movement of the latter.
- Each runway of a table is provided at its discharge end with a curved splash-plate or hopper 21, which directs the water and material into the corresponding runway of a succeeding lower table, but does not interfere in any way with the raising and lowering of the latter.
- the passage of the water from one runway to a succeeding one and in a reverse direction causes each time a turning over of the material and a succession of rearrangements of the particles, so that a most thorough washing and separation takes place.
- Means must be provided whereby to vary the pitch of the tables according to the head of water or the character of the material undergoing treatment and to drop the tables down so as to permit the removal of the screens, since the tables are normally disposed compactly one above the other.
- the raising and lowering' of the tables may be accomplished by a variety of means. I have illustrated a lever 22, fulcrumed on lthe frame abovethe tables, as at 22', with the weight end of the lever disposed about midway of the length of the tables.
- Rods 23 23 depend from the lever and are adapted to engage pins, hooks, or projections 24 on opposite ends and sides of each box. Thus to lift or lower one end of a box the rods 23 would be engaged with pins 24 at that end.
- rIhe means for effecting this vibration is here shown as comprisng a horizontal spring-arm 28, secured fast at one end and connected to the under side of frame 26, as shown in Figs. 6, 7, and adapted to be operated on by a ratchet-wheel 29. Any suitable means may be employedto rotate wheel 29.
- the water running over the tables may be made to furnish the required power by interposing an overshot wheel 30 in the path of water-discharge from sluice 28.
- the shaftof wheel 30 carries a pulley 31, around which passes a belt or cord 32, running toa pulley on the shaft of ratchet 29.
- a gold-saving' apparatus the combination with a sluice-boX, and a grizzly in lthe bottom thereof and comprisinga plurality of spaced bars extending in the direction of the 'current-flow, and a hinged closure for the grizzly said closure normally pendent beneath the grizzly and including bars extending in the direction of the current-How and adapted, when the closure is moved upwardly about its hinge connection, to close the interspaces between the bars of the grizzly, whereby the iiow of the current is diverted.
- a gold-saving apparatus the combination with a sluice-box, and a grizzly in the bot- IOO torn thereof and comprising a plurality of spaced bars extending in the direction of the current-flow, and a hinged closure for the grizzl y said closure normally pendent beneath the grizzly and including bars extending in the direction of the current- How and adapted, when the closure is moved upwardly about its hinged connection, to close the interspaces between the bars of the grizzly whereby the flow of the current is diverted, means for raising and lowering the closure and means for holding the closure in its closed position.
- a sluice-boX of a grizzly in the bottom of said sluice-box said grizzly comprising a plurality of bars extending in the direction of the current-flow, anda hinged closure for said grizzly, said closure pendent beneath the grizzly, and comprising a grating having bars staggered relative to the bars of the grizzly, a lever fulcrumed above the grizzly, connections between the lever and the free end of the grating and means for locking the lever and holding the grating in a closed position.
- a gold-saving apparatus the combination withatable having partitions and a concentrating-surface, of a screen overlying said surface and comprising screen -plates and frames therefor having upper and lower plates between which the edge of said screen-plate is fitted said partitions interposed between adjacent frarnes and said upper plate having a drop portion overhanging the inner edge of the lower plate and adapted to position the screen-plate substantially flush with the under side of the lower plate, and levers fulcrurned to the partitions and having one portion bear upon the upper plate and thereby lock the screen-frames in position.
- each of said screen-sections having a frame which includes upper and lower plates between which the edge of the screen-plate is received ⁇ said upper plate having a drop portion overhanging the inner edge of the lower plate and adapted to position the screen-plate substantially flush with the under side of the lower plate, one of said partitions interposed between the adjacent edges of each pair of frame-plates, cross-plates secured to the drop portions of the upper frame-plates, and levers fulcrumed upon the partitions and having their lower ends adapted to engage the upper frame-plates to lock the frames in place.
- a gold-saving apparatus the combination with a sluice and a concentrating-table upon which the sluice delivers, of a screenframe on the table and comprising upper and lower side plates between which the screen is removably clamped, said upper plates having drop portions extending over and beyond the inner edge of the lower plates and rigid connections between the plates on the opposite sides of the frame, and means for securing the screen to these connections.
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- Combined Means For Separation Of Solids (AREA)
Description
J. A. CLARK. GOLD S-AVING APPARATUS.
APPLICATION FILED AUG. 1, 1904.
No. 801,968. PATENTED OCT. 17, 1905.
w/TNESSES, A /N VEN TOR, l was. 5 Zap/)2. M
No. 801,968. l PATENTEDOGT. 1'7, 1905.
, J. A. CLARK.
GOLD SAVING APPARATUS.
APPLICATION FILED AUG. 1,1904.
3 SHEETS-SHEET 2.
.wm/5555s, N VEN TUR, @m55/@m f l WM( m@ No. 801,968. PATENTED 00T.17, 1905. J. A. CLARK.
GOLD SAVING APPARATUS.
APPLICATION FILED AUG.1.1904.
sHEETS--SHEET 3` F/G.. E. F76. 7'.
UNITED sTATns PATENT CFFICE.
GOLD-SAVING APPARATUS.
Specification of Letters Patent.
Patented Oct. 1'?, 1905.
Application filed August 1, 1904. Serial No, 219,041.
T0 all w/wm t may concern:
Be it known that I, JOHN A. CLARK, a citizen of the United States, residing at Yankee Hill, in the county of Butte and State of California, have invented new and useful Improvements in Gold-Saving Apparatus, of which the following is a specication.
My invention relates to improvements in gold-saving apparatus for use particularly in hydraulic and other placer mines.
This invention consists of parts and the combination of parts, which will be more fully explained by reference to the accompanying drawings, in which- Figure 1 is a side elevation, partly in section, of my invention. Fig. Q is a section of a portion of a table, showing screen-frame and locking means therefor. Fig. 3 is a side elevation of same. Fig. 4 is a plan view of a sluice and a set of tables. Fig. 5 is a longitudinal section of sluice, showing operatinglevers for grizzly-gate. Fig. 6 is a side elevation, partly in section, of table and vibrating screen. Fig. 7 is across-section of same.
A represents a sluice-box carrying the rocks, boulders, and earth just as they come from the mine under the impetus of perhaps several hundred inches of water. Interposed in the bottom of this sluice is a grizzly or grating 2, comprising a series of parallel-spaced iron bars extending lengthwise of the sluice, through which the sands, gravels, and material less than a certain size, together with some water, are discharged into suitable hoppers 3 and directed thence to opposite sides upon the aprons 4 and from there upon the tables 5. v
In order to regulate the amount of discharge through the grizzlies or grizzly-sections, (for preferably the grizzly is made in sections, as here shown,) I provide a hinged grating 6, pendent beneath a section of the grizzly and adapted to be folded up in the direction of the current-flow to close the interspaces of the grizzly. This grating or closure 6 is preferably formed of iron or steel bars, substantially A-shaped in cross-section and staggering with the bars of the grizzly. It may be operated by any suitable means, as the levers 7 and links, rods, or chains 8, connecting with the free end of the grating. The levers are fulcrumed above sluice A, and the rods 8 pass down through the grizzly near the side of the sluice-box. By pressing down on the lever the grating is raised to close the corresponding grizzly apertures and to a great extent if not quite cut off the passage of material and water therethrough. The closure is held in lifted position by any retaining means-as, for instance, the hook 9, engaging lever 7. Each section of the grizzly might be provided with a similar closure. By this construction it is possible to regulate the amount of water and material for the tables and to cut off discharge to any set of tables for purpose of clean-up without shutting down the mine, as results when the water in sluice. A is turned off.
The tables 5 may be of any number. Preferably they are in series, as here shown, one above the other, oppositely inclined and each adjustable vertically in suitable guides in a framework 10.
I have illustrated the tables as having an underneath cross-har 11 at each end, the ends of the cross-bars being movable in the vertical guides 12 and supported on pins 13, passing through perforations in the guides. Thus either end of a table may be raised or lowered to vary the pitch. The tables may be of any length or width and are divided longitudinally into a plurality of sluices or runways by shallow partitions 14.
The surface of a table is riffled or covered with canvas, as shownat 15, Fig. 2, and over this canvas is stretched metal screening or fine wire-netting 16, which has been found to possess the quality of retarding the velocity of the undercurrent and to assist materially the separation of the sands and values from the gangue and coarse barren matter. However, in order to prevent the sands packing at any one place to abnormal depths, and so to a degree destroying the efficiency of the screening, it is preferred that the screen be secured on all sides. When a clean-up is necessary, the screen is taken up and the canvas swept and washed off.
As it is necessary to clean up every few hours, it is essential that means be provided for quickly taking up and putting down the screens. Consequently the screen is arranged in sections of a width equal to that approximately of the concentrating-surface between the partition 14 and of such length easily to be handled. I have found that two and ahalf or three feet is a good length for these sections. Each section is framed in a metal frame and each frame is adapted to be removably locked in its place on the table. These screenframes comprise two lower side plates 17 and two upper side plates 18, between which two IIO opposite edges of a screen-section are bolted. The plates 18 have each an inside drop portion 19 overhanging the inner edge of its respective plate 17 and adapted to bring the screen flush with the under side of the plates 17, so that the screen will lie fiat on the canvas. The upstream and downstream edges of the screen are bolted to the under side of the thin cross-plates 20, which are suitably secured to the plates 18. A screen-sectionis quickly taken out of its frame by removing the plates 17 and unbolting the screen from the cross-plates 20. rIhe frames are laid on the canvas one after another and are removably held in position by suitable means, as the locking devices 21, which consist of levers fulcrumed in the parts 14, adapted when vertical to press on the sides of the frames and prevent any movement of the latter. To take out a screen-frame or to replace a torn screen or a bad section of canvas, it is'only necessary to give the levers 21 a knock to one side and both the screen-frame and canvas are loosened, since the canvas is held in position by the framesand their locking means. With these screens thus framed and arranged in sections it is an easy matter to take them up andlay them down, and the work is done rapidly, and no injury results to the screens or the canvas on` the tables, as where there is frequent tacking, nailing, and the like.
It has been found that by using a series of superposed oppositely-inclined tables, as here shown, each provided with removable screens, a very complete separation of the sands and values is effected and the saving of the line gold becomes very near if not quite perfect. Each runway of a table is provided at its discharge end with a curved splash-plate or hopper 21, which directs the water and material into the corresponding runway of a succeeding lower table, but does not interfere in any way with the raising and lowering of the latter. The passage of the water from one runway to a succeeding one and in a reverse direction causes each time a turning over of the material and a succession of rearrangements of the particles, so that a most thorough washing and separation takes place.
Means must be provided whereby to vary the pitch of the tables according to the head of water or the character of the material undergoing treatment and to drop the tables down so as to permit the removal of the screens, since the tables are normally disposed compactly one above the other. The raising and lowering' of the tables may be accomplished by a variety of means. I have illustrated a lever 22, fulcrumed on lthe frame abovethe tables, as at 22', with the weight end of the lever disposed about midway of the length of the tables. Rods 23 23 depend from the lever and are adapted to engage pins, hooks, or projections 24 on opposite ends and sides of each box. Thus to lift or lower one end of a box the rods 23 would be engaged with pins 24 at that end. If the opposite end of a box was to be raised or lowered, the rods 23' would be engaged with the pins at that end, while if a box was to be raised or lowered bodily both sets of rods would be engaged, so that the box could be entirely suspended from the lever. Of course' where the tables were very long or very heavy a leverlcould be disposed at each end, in which case it would require an operator at each lever where a box was to be moved bodily.
The iinal segregation and collection of the black sand and values passing beyond the tables is eected 'by sifting through a fine screen 25, mounted in -a suitable spring-frame 26, disposed in an opening in the bottom of the lowermost table. It has been usual to try to sift these heavy wet sands by a horizontal reciprocating or shaking movement; but the more they are shaken in that manner the tighter they pack and cling to the screen. I have found that by vibrating the screen in a direction at right angles to its surface, alternately lifting and depressing it by sudden blows, the heavier sands-and values are forced through, while the Water and barren sands and gangue pass on over. rIhe means for effecting this vibration is here shown as comprisng a horizontal spring-arm 28, secured fast at one end and connected to the under side of frame 26, as shown in Figs. 6, 7, and adapted to be operated on by a ratchet-wheel 29. Any suitable means may be employedto rotate wheel 29. For convenience and economy the water running over the tables may be made to furnish the required power by interposing an overshot wheel 30 in the path of water-discharge from sluice 28. The shaftof wheel 30 carries a pulley 31, around which passes a belt or cord 32, running toa pulley on the shaft of ratchet 29. The motion irnparted to wheel 30 by the body of water falling from sluice 27 is'transmitted to the ratchet 30, which causes the arm 28 and connections 33 to be vibrated rapidly and a consequent vibratory motion or shock is given the frame 26 and its screen 25.
Having thus described my invention, what I claim, and desire to secure by Letters Patent, is-
l. In a gold-saving' apparatus the combination with a sluice-boX, and a grizzly in lthe bottom thereof and comprisinga plurality of spaced bars extending in the direction of the 'current-flow, and a hinged closure for the grizzly said closure normally pendent beneath the grizzly and including bars extending in the direction of the current-How and adapted, when the closure is moved upwardly about its hinge connection, to close the interspaces between the bars of the grizzly, whereby the iiow of the current is diverted.
2. In a gold-saving apparatus the combination with a sluice-box, and a grizzly in the bot- IOO torn thereof and comprising a plurality of spaced bars extending in the direction of the current-flow, and a hinged closure for the grizzl y said closure normally pendent beneath the grizzly and including bars extending in the direction of the current- How and adapted, when the closure is moved upwardly about its hinged connection, to close the interspaces between the bars of the grizzly whereby the flow of the current is diverted, means for raising and lowering the closure and means for holding the closure in its closed position.
3. In a gold-saving apparatus the combination with a sluice-boX and a grizzly in the bottom thereof and comprising a plurality of spaced bars extending in the direction of the current-flow, a hinged closure for the grizzly said closure normally pendent beneath the grizzly an'd including bars extending in the direction of the current-flow and adapted, when the closure is moved upwardly about its hinged connection, -to close the interspaces between the bars of the grizzly whereby the iow of the current is diverted, a fulcrumed lever and means connecting one end thereof with the closure, and a latch mechanism for securing the lever and holding the closure in its closed position.
4. In a gold-saving apparatus the combination with a sluice-boX of a grizzly in the bottom of said sluice-box said grizzly comprising a plurality of bars extending in the direction of the current-flow, anda hinged closure for said grizzly, said closure pendent beneath the grizzly, and comprising a grating having bars staggered relative to the bars of the grizzly, a lever fulcrumed above the grizzly, connections between the lever and the free end of the grating and means for locking the lever and holding the grating in a closed position.
5. In a gold-saving apparatus the combination withatable having partitions and a concentrating-surface, of a screen overlying said surface and comprising screen -plates and frames therefor having upper and lower plates between which the edge of said screen-plate is fitted said partitions interposed between adjacent frarnes and said upper plate having a drop portion overhanging the inner edge of the lower plate and adapted to position the screen-plate substantially flush with the under side of the lower plate, and levers fulcrurned to the partitions and having one portion bear upon the upper plate and thereby lock the screen-frames in position.
6. In a gold-saving apparatus the combination ofa table having vertical partitions, a concentrating-surface on the table, a sectional screen overlying the concentrating-surface, each of said screen-sections having a frame which includes upper and lower plates between which the edge of the screen-plate is received `said upper plate having a drop portion overhanging the inner edge of the lower plate and adapted to position the screen-plate substantially flush with the under side of the lower plate, one of said partitions interposed between the adjacent edges of each pair of frame-plates, cross-plates secured to the drop portions of the upper frame-plates, and levers fulcrumed upon the partitions and having their lower ends adapted to engage the upper frame-plates to lock the frames in place.
7. In a gold-saving apparatus the combination with a sluice and a concentrating-table upon which the sluice delivers, of a screenframe on the table and comprising upper and lower side plates between which the screen is removably clamped, said upper plates having drop portions extending over and beyond the inner edge of the lower plates and rigid connections between the plates on the opposite sides of the frame, and means for securing the screen to these connections.
In testimony whereof I have hereunto set my hand in presence of two subscribing witnesses.
JOHN A. CLARK. Witnesses:
W. E. DUNCAN, Jr., E. H. RUTHERFORD.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
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US21904104A US801968A (en) | 1904-08-01 | 1904-08-01 | Gold-saving apparatus. |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US21904104A US801968A (en) | 1904-08-01 | 1904-08-01 | Gold-saving apparatus. |
Publications (1)
Publication Number | Publication Date |
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US801968A true US801968A (en) | 1905-10-17 |
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ID=2870454
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
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US21904104A Expired - Lifetime US801968A (en) | 1904-08-01 | 1904-08-01 | Gold-saving apparatus. |
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Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4199441A (en) * | 1978-07-31 | 1980-04-22 | Ross Lorne M | Placer mining sluice box apparatus and method |
US4371435A (en) * | 1981-10-22 | 1983-02-01 | Colin Eckersley | Placer mining sluice |
US20100193406A1 (en) * | 2009-02-04 | 2010-08-05 | Larry Allen Alderson | Equipment for use in the extraction of placer gold from gravel and sand deposits |
US8678192B1 (en) | 2010-10-27 | 2014-03-25 | Michael Pung | Gold cube |
US8770412B2 (en) | 2012-12-07 | 2014-07-08 | Gerald Lee Miller | Gravimetric mineral processing device and method for its use |
-
1904
- 1904-08-01 US US21904104A patent/US801968A/en not_active Expired - Lifetime
Cited By (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4199441A (en) * | 1978-07-31 | 1980-04-22 | Ross Lorne M | Placer mining sluice box apparatus and method |
US4371435A (en) * | 1981-10-22 | 1983-02-01 | Colin Eckersley | Placer mining sluice |
US20100193406A1 (en) * | 2009-02-04 | 2010-08-05 | Larry Allen Alderson | Equipment for use in the extraction of placer gold from gravel and sand deposits |
US9132431B2 (en) * | 2009-02-04 | 2015-09-15 | Larry Allen Alderson | Equipment for use in the extraction of placer gold from gravel and sand deposits |
US8678192B1 (en) | 2010-10-27 | 2014-03-25 | Michael Pung | Gold cube |
US8770412B2 (en) | 2012-12-07 | 2014-07-08 | Gerald Lee Miller | Gravimetric mineral processing device and method for its use |
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