Патент USA US2129874код для вставки
Sept E3, Mw» .1. Ross ¿mgm DRY coNoENTRAToR Filed April 8, 1937 2 Sheets-Sheet l ‘ DRY GONCENTRATOR Filed April 8, 1957 Za .2 sheets-sneak Syvum/JM qïaän f H 055 Patented Sept. 13, 1938 UNITED STATES PATENT GFFIQE 2,129,874 DRY CONCENTRATOR John Ross, Custer, S. Dak. Application April 8, 1937, Serial No. 135,775 3 Claims. This invention relates to concentrators and IB is a hopper or bin 24 having a discharge pipe trating gold sands. The general object of the invention is to pro 25 discharging into the hopper 23 and provided with a shut-off gate 26. Surrounding the feed tion including a concentrating tubular element through which the gold containing the sand is blown, the bottom of the concentrator being pro vided with riffles so that the heavier materials 10 will fall to the bottom of the concentrating tube while the lighter` materials, such as sand and gravel will be blown out of the concentrator tube at the end thereof. Another object is to provide means whereby 15 the material being concentrated may be heated before being discharged into the concentrating tube, and another object is to provide means for regulating the flow of materials to the concen trating tube. A further object is to» provide means whereby the concentrate may be readily removed from the concentrating tube when necessary. Other objects will appear in the course of the following description. 25 My invention is illustrated in the accompany ing drawings wherein: Figure l is a side elevation of a dry concen trator constructed in accordance with my in vention. Figure 2 is an enlarged section on the line 2_2 30 of Figure 1. Figure 3 is an enlarged vertical section through the feeding mechanism and a portion of the 35 Disposed at any desired distance above the pipe particularly to a dry concentrator for concen 5 vide a concentrator of a Very simple construc 20 (Cl. 209-477) concentrating tube. Referring to these drawings, I0 designates a concentrating tubular member which may have any desired diameter and which is supported adjacent its forward and rear ends or at any suitable points by supporting brackets II. The 40 tube is embraced by a band I2 extending from one supporting bracket, the band being split and held clamped upon the tube by the bolt I3. Preferably the forward end of the tube IIJ is screw-threaded for the attachment, if desired, of a pipe coupling I4. The rear end of the tube I0 is operatively connected to a fan or blower casing l5 of any suitable or usual construction having therein the fan I6 which is illustrated as being driven by a belt or sprocket Il from a 50 motor I8, preferably an internal combustion motor. The tube I D is formed in two sections con nected by a four-way pipe fitting I9. The down wardly discharging branch of this pipe fitting 55 is closed by a removable plug 20. Inserted in the upwardly extending branch of this> pipe fit ting I9 is a pipe reducing bushing 2l. Extend ing downward through this bushing and verti cally adjustable therein- is a feed tube 22, the 60 upper end of which terminates ín a hopper 23. tube 22 is a sleeve 2'I which may be connected by a pipe 28 to the exhaust from the motor I8 so that the heated products of combustion from this motor may be discharged into this sleeve 2l and surround that portion of the feed pipe 22 just above the bushing 2|. 10 Disposed at intervals along the bottom of the tube l0 are the forwardly and upwardly inclined riffles 29, each riffle being approximately semi circular in form, as illustrated. As illustrated. the tube I il is formed with a plurality of diagonal kerfs 30 into which the rifñes 29 are inserted. These riilles are preferably one-third as high as the inside diameter of the tube and slant toward the discharge end of the tube. While I do not wish to be limited to this, yet 20 preferably hard rubber riffles are used as these will wear longer than steel riiiles. When, how ever, the sand or gravel is moist, the steel riflies work the best as the material slides over them easier. These riiiies are spaced from 4” to 6” apart, according to the size of the tube. 25 The rifñes are inserted in the kerfs 3B and after the rifñe is put in place, the walls of the kerf are slightly battered with a hammer so that they overhang the riiiie slightly and this will 30 prevent the rili‘le from falling out while the shoul ders or corners 3I prevent the riflies from slipping sidewise. The feed tube 22 is one-third as large in diam eter as the concentrating tube I0. The blast of air must be strong enough to keep sand and gravel moving and this, of course, is regulated either by proper valves or by controlling the engine speed. The forward end of the tube I0 is supported slightly higher than the feed end of the tube I0 and I find that l" to the foot gives the proper angle. This permits the washing out of the concentrating tube when the concentrat ing operation is finished. To clean out the concentrating tube, the gate 26 is first closed and the blower is run until the feed tube and feed hopper are entirely empty. Then the bolt I3 of the clamp I2 is loosened. This permits the forward section of the concen trating tube to be rotated within the fitting I9 and given a one-half turn. The riiiies are then 35 40 45 50 at the top of the concentrating tube and by tapping the tube with a hammer, all the concen trates will drop to the bottom of the tube or onto the smooth side of the inverted tube. 'I’hen 55 a suitable receptacle is placed beneath the plug 20 and the plug removed. By pouring a pail or two of water into the discharge end of the tube Il), the water will ñow rearward and wash all the concentrates back an-d they will come 60 2,129,874 2 out through the lower opening of the four-Way pipe fitting and be discharged into the recepta cle. The plug 20 should be left out until all the water has drained out of the tube before start ing up again. By screwing the feed tube 22 up or down through the reducing bushing 2l, the feed may The gravel that travels through the concentrator must be screened through a %” mesh screen so that the blower can properly handle it. Of course, it is to be understood that the screened gravel is discharged into the bin or hopper 24 and from there it passes through the feed spout into the feed tube hopper and thence into the be regulated. By screwing the feed tube up, the feed tube and into the concentrator. There the feed will be increased and will be decreased by ì blower blows it through the concentrating tube 10 screwing the feed tube down. Of course, where the gravel is damp, the feed must be slowed up somewhat and while the moisture does not inter fere with proper separation, yet I have made provision to apply a little heat around the feed tube, as before described, without any additional cost to the operator. It is to be noted that the feed pipe 25 extends straight downward from the bin or hopper 24 and that the pipe 22 also extends straight downward. 20 This is necessary Where this concentrator is be ing used for placer sands and gravel because such sand or gravel is very likely to be damp. This dampness does not occur where ore has to be ground up for concentration, but it does occur where this concentrator is used, as it is particu larly designed to be used for placer mining. If the feed tube or any other feeding member were inclined even at a steep angle, there is liability of the sands, because of their moisture, sticking to the inclined surface and clogging. This is not the case, however, where the feed tube is verti cal. Furthermore, I have provided a heating means, namely, the spaced sleeve 21, for driving olf any latent moisture which may still remain in the sand. It is also an absolute necessity in an appa ratus of this kind that the feed should be capa ble of being regulated and this is secured by the adjustment of the feed tube 22 nearer to or further from the bottom of the concentrating pipe. If the feeding means is not capable of adjustment, then the machine will either be over loaded or run empty. The tube 22 will feed the sand down into the concentrating tube no faster than the blower carries the sand away. Further 45 more, with this construction, should the blower stop from some cause, the sand will stop feeding into the tube, in other words, it will build up beneath the lower end of the tube and as it can not pass laterally from the tube, it will stop all feed from the tube. By placing the blower l5 at the rear end of the concentrating tube lll and placing the feed in front of the blower, I prevent the blower from being scored or injured by the ñne particles of and over the riñles. Inasmuch as the gold is much heavier than the sand and gravel, it will settle to the bottom of the concentrating tube while the sand and gravel will be blown out. As before stated, the discharge end of the concen trating tube IS is provided with a coupling I4 s0 15 that the concentrating tube may be extended, if necessary, by connecting another piece of tubing having, of course, the riflies 29 therein. Where there is a good deal of fine or flour gold in the sand and gravel together with coarse gold 20 or nuggets larger than %" or larger than the reticulations of the screen, it is advisable to use a larger screen and use two concentrators on one machine side by side of the same size and design. Then the undersized material which has passed 25 through the screen is again screened and this ñne material is run through one concentrator and the coarser material through the other. rline blast of air that acts upon the ñne material must be reduced in strength while the blast of 30 air that carries away the coarser material may be increased. By doing this, all the ñne and all the coarse gold can be saved. Obviously where a gang of these machines are being used, all the blowers may be operated from one shaft 35 driven by one motor. What is claimed isi 1. A dry concentrator of the character de scribed, including a four-way pipe fitting, a tubu lar concentrator section rotatably engaged with the forward end of the pipe fitting and having a .49 series of riffles on its bottom, a second pipe sec tion connected to the rear end of the pipe fitting, a blower communicating with the last named pipe section, a cleanout plug vdisposed at the lower end of the pipe section, a pipe reducing bushing in the upper end of the four-way pipe section, a feed tube extending through the bush ing and vertically adjustable therein, and means for regulatably discharging sand and gravel into 50 said hopper. 2. A dry concentrator of the character de scribed, including a concentrating tube having noted that the tube lll forward of the feed tube 22 a series of forwardly inclined bañles disposed at spaced distances in the bottom of the tube, means 55 for rotatably supporting the tube whereby it may be turned through a half-circle, a blower dis charging into the rear end of the tube, a feed pipe discharging into the rear end of the tube, and a cleanout opening at the rear end of the is unobstructed except by the relatively shallow tube, the concentrating tube being upwardly in riffles in the bottom of the tube. clined towards its forward end whereby when the concentrating tube is inverted and the clean out opening is opened, the concentrate will fall to the bottom of the concentrating tube and may be (lo washed out of the cleanout opening. 3. In a dry concentrator of the character de scribed, a concentrating tube, the bottom of the tube having a series of kerfs cut therein and slanting toward the forward end of the tube, and 70 baflies inserted and held in place in said kerfs. JOHN ROSS. sand which would be the case were a suction fan used for drawing the sand and gravel through the concentrating tube. Furthermore, a suction fan has much less power than a blower. It will be Thus there is nothing which will impede the free movement of 'the sand and gravel and lighter material along ~ the tube, and there is nothing which will tend to disturb the gold or heavier material which has fallen into the spaces between the riiiles. This concentrator can be built in different sizes, from a hand-operated machine up to a size that will handle a large amount of sand and 70 gravel. I have found that it will work in con nection with any kind of gravel screening plant.