Abstract:
An adjustable splitter assembly at any position along the spiral trough and the splitter is angled to a fixed position pressed against the trough and locked against movement by a long arm selectively clamped in one hook of a retainer having spaced hook sockets, the retainer being attached to the outer rim of the trough either upstream or downstream from the splitter. The splitter may be angularly adjusted to position its leading edge at different locations along an arc with respect to the stream of particles flowing down the trough by moving the arm to another selected hook socket.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     Not Applicable. 
    
    
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH 
     Not Applicable. 
     REFERENCE TO A MICROFICHE APPENDIX 
     Not Applicable. 
     BACKGROUND OF THE INVENTION 
     (1) Field of the Invention 
     This invention relates to a spiral trough separator for separating heavy particles from light particles where the particles normally result from mining operations; and, more particularly, this invention relates to an assembly for adjustment of a splitter and maintaining same in position in the spiral trough so as to separately recover one particle fraction from another. 
     (2) Description of the Related Art 
     U.S. Pat. No. 5,452,805 issued Feb. 9, 1993, describes and claims a spiral trough separator having spaced groups of parallel grooves in the trough to enhance the separation of solids from slurries of those solids. 
     U.S. Pat. No. 4,189,378 issued Feb. 19, 1980, describes and claims a spiral separator for dividing mineral fractions of different sizes of particles having at various locations in the helical trough a slotted opening through which a slurry of particles may be drawn off as a product; the opening being controlled in length by a slide and a splitter project upwardly into the trough, and the stream in the trough may be divided into different parts of the opening and thereafter to different product recovery zones of concentrate and middlings, for example. The splitter position is controlled by a manual adjustment slide mechanism allowing it to be positioned at any desired location from one end to the other of the slotted opening. This arrangement is not only complicated and expensive and relies on changes of size of the opening and associated piping, but is subject to potential jamming of the slide when fine particles become lodged in the slide mechanism. 
     BRIEF SUMMARY OF THE INVENTION 
     The present invention is an adjustable assembly for positioning a splitter in the trough of a spiral separator which carries a slurry of particles down the spiral for the purpose of separating the particles into fractions of different specific gravities. The assembly includes an elastomeric splitter vane attached to one end of a long springy rod while the other end of the rod is locked in place by any one of a plurality of spaced hook sockets. The rod is designed and shaped to press the splitter against the trough when the free end is locked into place by a selected hook socket, and this pressure on the splitter prevents it from becoming dislodged from the trough and thereby failing to produce a sharp separation between different particles. The splitter when locked cannot be moved even during high pressure washing of the spiral. When unlocked, the force from the rod pressing the splitter against the upper surface of the spiral is released and the splitter can be readily pivoted to a new position, without any jamming due to the slurry, and the rod relocked into another hook socket. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The novel features believed to be characteristic of this invention are set forth with particularity in the appended claims. The invention itself, however, both as to its organization and method of operation, together with further objects and advantages thereof, may best be understood by reference to the following description taken in connection with the accompanying drawings in which: 
     FIG. 1 is a front elevational view of a typical spiral trough separator for the separation of mineral particles of a selected particle size from a slurry of particles having a wide range of particle sizes with a couple of the adjustable splitter assemblies according to this invention mounted thereto; 
     FIG. 2 is a top plan view of the separator of FIG. 1 without splitter assemblies; 
     FIG. 3 is a side elevational view of the hook socket retainer according to the first embodiment of the invention which is attached to the rim of the trough of the separator of FIG. 1; 
     FIG. 4 is an end elevational view of the hook socket retainer shown in FIG. 3 with the rim shown in broken lines; 
     FIG. 5 is a perspective view of the splitter according to the first embodiment of the invention; 
     FIG. 6 is a plan view of the splitter and retainer of the first embodiment, with the splitter in a selected position in the spiral trough of the separator; 
     FIG. 7 is a side elevational view of the hook socket retainer according to the second embodiment of the invention; 
     FIG. 8 is a perspective view of the splitter according to the second embodiment of the invention; and 
     FIG. 9 is a plan view of the splitter and retainer of the second embodiment on the spiral trough. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     This invention is an improvement in the art of spiral conveyor separators which are commonly in use in the field of mining and metallurgy where it is important to separate particles of rock from particles of valuable minerals, such as rutile, ilemite, chromite, etc., or metals, e.g., gold. It has been known that by feeding aqueous slurries of metals and the rock naturally occurring with those metals into a vertically spiral trough the forces of gravity and centrifugal energy will cause the heavier particles to separate from the lighter particles sufficiently to allow a splitter to divert the two streams and permit the recovery of two different grades of particles. The feed to the spiral conveyor is the product of grinding and size separation techniques which result in particles of rock and metal that are about the same size although the rock particles are lighter in specific gravity than the metal particles. In order to recover the metal separated from the rock there must be a further separation of the heavier particles from the light particles, and the present invention is for that purpose. An aqueous slurry of the particles is the most convenient way of accomplishing that, because the slurry provides a flowing stream of particles that can be passed around turns and allow the particles to move separately from the water and find their own position based upon their weight. Generally the lighter particles will flow to the outer edges of the spiral and the heavier particles will remain closer to the center of the spiral. Of course, the higher speed of the slurry around the spiral will move the heavier particles away from the center due to centrifugal force. In any event these forces can be controlled by the speed of the slurry movement, and this control permits a separation to be reached at some controlled speed of slurry. 
     It is the purpose of the present invention to provide an intermediate separation of particles at one or more selected positions along the spiral instead of only one separation at the exit end of the spiral. This method permits a greater degree of control for the operator by allowing a drawoff of product wherever the desired separation occurs along the spiral rather than dedicating the entire spiral to a separation that only required a portion of the spiral rather than the entire length thereof. 
     In FIGS. 1 and 2 there is shown a portion of a vertical spiral conveyor having a spiral trough  10  which receives a feed slurry at some location above the upper limit of the drawing and discharges the slurry at some location below the lower limit of the drawing. The trough  10  is supported by a central axial column  12  and a plurality of support arms  13  extending horizontally outward from the central column  12 . A hook lock socket retainer  11  is positioned along the outer rim of the trough  10  near wherever a separation product is to be located, as will be explained hereinbelow. 
     In FIGS. 3-5 there are shown the details of the splitter  15  and retainer  11  positioned to function in separating different sizes and grades of partical product. In FIG. 6 the direction of the slurry flow  28  is illustrated to be clockwise around central column  12 . One or more hook socket retainer  11  is shown in detail in FIGS. 3 and 4 and will be described more fully hereinafter. The slurry has divided itself into two parts (shown by arrows A and B) and this permits a separation by the placement of splitter  15  with its sharp end  18  upstream so as to direct the desired product into retrieval tube entrance  26  where it will be drawn off as a product. Splitter head or vane  15  is physically connected to arm  14  which, in turn, is held rigidly in position by being in a hook of the socket retainer  11 . Splitter head  15  is maintained steady by spine or pivot portion  16  pressed in a recess or hole in trough  10  and is attached thereto by a washer  30  and threaded nut  31  generally shown in FIG.  5 . Thus, the particles of the slurry intended to be diverted by splitter head  15  cooperates with the position of retrieval tube entrance  26  in a manner well known in the art. 
     Spine  16  passes through splitter head  15  and is pivotally or rotatably attached to trough  10  to pivot as indicated by arrow  20 . In this embodiment the spine  16  is located at the downstream end portion  19  of head  15 . The upstream end  18  of head  15  is nonrotatably attached to arm  14  by support  17 . The bottom surface of head  15  may be curved or substantially planar to be similar to the surface of spiral trough  10  so as to form a reasonably snug seal when head  15  is pressed against trough  10  by the force of the spring or downward bend of the arm  14  when the arm  14  is moved into its locked position. Spine  16  preferably is threaded on its end to receive a washer  30  and a nut  31  which may be tightened without compressing head  15  against the bottom surface  32  of the spiral trough  10  without effecting the pivoting of spine  15 . The outer shape of head  15  is somewhat like that of a boat with the upstream end  18  sharp like the bow and the downstream end  19  is enlarged like the aft end of a boat. The two ends  18  and  19  are connected by two similarly curving streamlined walls which will allow the liquid slurry to pass by on both sides with as little disturbance as possible. 
     Arm  14  is of springy metal, such as stainless steel, and is sufficiently long to reach beyond the outer rim of trough  10  and be pressed into the selected hook of the socket retainer  11 . If the arm  14  is shaped correctly it will, when hooked into strip  11 , apply a downward bending force to elastomeric head  15  causing the bottom surface  33  thereof to be pressed tightly against the upper surface  34  of trough  10 . 
     In FIG. 6 it may be seen that by providing a product drawoff hole or entrance at  26  connected to appropriate retrieval piping or tubing, a desired product of particles of a special density in an aqueous slurry may be retrieved. The positioning of a splitter head  15  and arm  14  may be placed appropriately to divide the desired product into stream A to exit through entrance  26  while the remainder B of the slurry can continue on down the trough  10  to another separation or to collection point. The position for splitter spine  16  is determined adjacent a drawoff hole  26  and a hole is drilled there to fasten the spine  16  at that point. The hook socket retainer  11  is located upstream, in this embodiment, at a suitable place along outer rim  27  of trough  10  and another hole is drilled therethrough to affix the retainer  11  to the rim  27  of trough  10 . 
     FIG. 3 shows a hook socket retainer  11  as a punched out flat plate. The retainer  21  will be bent along a radius to curve same to fit along the outside rim  27  of trough  10  when in use. Along the top edge of retainer  21  are a series of identical hook sockets  22 . These sockets  22  may be cut by hand or punched out on a press. Each socket  22  has a hook-shaped body surrounding a hook-shaped space  25  so as to provide about  6 - 8  hooks spaced along retainer  11 . The arm  14  of the splitter head  15  will slide into a selected space  25  and be retained thereat due to the springy material from which the arm  14  is formed, as well as the shoulder  35 . Generally, the arm  14 , shown in broken lines in FIG. 3, is about perpendicular to space  25  so that it can be readily placed and removed therefrom. Wings  23  at each end of strip  21  are bent over as shown in FIG. 4, so that they clip over the outside rim wall  27  of trough  10  to hold the strip  21  in a steady position. A bolt connector  36  passes through hole  24  of retainer  21  and holds same firmly against the outside of trough  10  and prevents disengagement of clip wings  23  from their positions illustrated in FIG.  4 . It therefore, is apparent that a retainer  21  is readily available to be attached where needed to steady a splitter  15  wherever desired along trough  10 . 
     Sometimes it may become necessary to apply the principles of this invention in a reverse manner, e.g., when an easier access to the arm  14  may dictate or if the arrangement of an array of many spirals is such that it makes the use in the manner shown in FIGS. 1-6 impractical. FIGS. 7,  8  and  9  depict this reverse modification and generally correspond to FIGS. 3,  5  and  6 . The splitter upstream end  48  remains above the drawoff entrance  26  as shown in FIG.  9 . However, the head  45  is attached at the far end of arm  44  by support  47  with spine  46  being intermediate of the ends of arm  44  and passing through head  45  adjacent larger end  49  of head  45 . The lock tooth retainer  51  is formed with a plurality of spaced hooks  52  in the form of sockets  55  communicating with an elongated common slot  60  via generally vertical access passageways  61 . When the arm  44  is locked in a socket  55  shown in full lines in FIG. 7 there is a compressive force transferred from the springy steel arm to the compressible head  45  to seal the head  45  to the spiral upper surface  34  of the spiral  10 . When the position of the arm  44  is to be adjusted, the arm  44  must be forced upwardly to clear shoulder  65  of socket  55 , pass down passageway  61  to slot  60  as shown by broken lines  44 . Accordingly, the head  45  is not compressed against the spiral upper surface  34  and may pivot about spine  41  in much the same manner as head  15  pivoted about spine  16  in the embodiment of FIGS. 3-6. The attachment wings or clips are illustrated in this embodiment at  53  and the support bolt hole  54  corresponds to hole  24 . 
     While the invention has been described with respect to certain specific embodiments, it will be appreciated that many modifications and changes may be made by those skilled in the art without departing from the spirit of the invention. It is intended, therefore, by the appended claims to cover all such modifications and changes as fall within the true spirit and scope of the invention.