Patents Assigned to Mineral Deposits Limited
  • Patent number: 4836926
    Abstract: A spiral separator 1 is provided with a first pivotally mounted splitter (6) having an upstream working edge for dividing a slurry descending the sluice into two streams (A,B). A second pivotably mounted splitter (8) is positioned downstream and radially outwardly of the first and divides stream B into two streams (C, D) the second splitter being moveable to a position adjacent the downstream end of the first.
    Type: Grant
    Filed: July 17, 1987
    Date of Patent: June 6, 1989
    Assignee: Mineral Deposits Limited
    Inventor: Hans J. Grobler
  • Patent number: 4795553
    Abstract: In a spiral separator of the kind used for the wet gravity separation of solids (Figs. 5 & 6) there are provided splitters (70,71,72) in vertically aligned troughs (20,21,22) which are operatively connected by a linkage (80) permitting adjustment of splitters in unison. Preferably the splitters are at corresponding locations of separate troughs and are in vertical register.
    Type: Grant
    Filed: November 17, 1982
    Date of Patent: January 3, 1989
    Assignee: Mineral Deposits Limited
    Inventor: Philip J. Giffard
  • Patent number: 4747943
    Abstract: This invention relates to a spiral separator (1) which is used for separating particulate material and which is able, when arranged in a linear array of such separators, to be adjusted in concert with the other separators in the array.Specifically the invention consists in a spiral separator (1) comprising a volute (2); a splitter blade (4) mounted below a discharge section (3) of the volute (2) for selected rotation about a substantially horizontal axis (5) parallel to the direction of flow in the volute (2), splitting being adjusted by the rotation of the splitter blade (2) about the axis (5).
    Type: Grant
    Filed: July 30, 1986
    Date of Patent: May 31, 1988
    Assignee: Mineral Deposits Limited
    Inventor: Phillip J. Giffard
  • Patent number: 4614580
    Abstract: A splitter assembly for a spiral separator comprises a blade (1) having an upstream working edge (11) and has a rail (3) mounted above the sluice floor (2) to which blade (1) is slideably mounted by means of arm (10) which engages rail (3).The lower end of working edge (11) is in contact with floor (2) and the position of contact is adjustable along a path extending between a radially outer and radially inner part of floor (2). In preferred embodiments splitter arm (10) is flexible and working edge 11 moves in a path which is curvilinear with respect to a vertical and a horizontal plane.
    Type: Grant
    Filed: December 21, 1984
    Date of Patent: September 30, 1986
    Assignee: Mineral Deposits Limited
    Inventor: Philip J. Giffard
  • Patent number: 4597861
    Abstract: In wet gravity separation of solids according to specific gravity an outer depleted band partly overlies an inner concentrate band limiting yield and/or purity of separated concentrate. The overlying depletion layer is diverted outwardly from inner wall (15) relative to the concentrate band. Deflection means (20) cause a bow wave in descending slurry which fans out the concentrate aiding precise setting of downstream splitter blade (18) as well as diverting the overlying depletion band towards outer wall (13). The water which has become separated from the slurry due to centrifugal force can be rehomogenized with the remaining concentrate by restricted passage between deflector means (22,26).
    Type: Grant
    Filed: December 7, 1984
    Date of Patent: July 1, 1986
    Assignee: Mineral Deposits Limited
    Inventor: Douglas C. Wright
  • Patent number: 4476980
    Abstract: The invention provides a spiral separator of the type for use in separating a pulp of water and minerals into mineral fractions of differing densities and having a helical trough (30) supported with its axis upright. The shape of the trough working surface profile (30) varies (FIGS. 2A-2D) from place to place along the trough. The profile has a point of maximum displacement (32A, 32B, 32C, 32D) at which profile (30) is at a maximum spacing below a notional straight line (40) joining the inner end (31) and outer end (22) of the trough working surface profile (30). The distance of the point of maximum displacement (32A, 32B, 32C, 32D) from one end (31 or 22) of the profile varies along the trough. A method for manufacture of troughs according to the invention is also described and claimed.
    Type: Grant
    Filed: November 17, 1982
    Date of Patent: October 16, 1984
    Assignee: Mineral Deposits Limited
    Inventor: Philip J. Giffard
  • Patent number: 4209386
    Abstract: A method and apparatus for the wet gravity concentration of particulate ores in which a cascaded series of concentrators may be arranged in a matrix array from a basic triangular unit comprising a first concentrator for dividing a pulp stream into two sub-streams of differing concentration and a pair of subsidiary concentrators for respectively dividing the sub-streams, the subsidiary concentrator dividing the richer sub-stream being arranged to remove at least part of its enriched stratum without intruding substantially into its feed grade stratum while the subsidiary concentrator dividing the poorer sub-stream is arranged to remove at least part of its depleted stratum without intruding substantially into its feed grade stratum. The method and apparatus are described with reference to both tray and cone concentrators.
    Type: Grant
    Filed: November 21, 1977
    Date of Patent: June 24, 1980
    Assignee: Mineral Deposits Limited
    Inventor: Philip J. Giffard
  • Patent number: 4183806
    Abstract: Simple, flow regulating tap-off means are provided in the bottom of a helical eluent supply conduit which is co-axial with a helical separator sluice in a gravitational separator. The tap-off means is an insert in the floor opening of the eluent conduit having an aperture in the insert and an inner lip at the top of the insert that does not extend above the floor of the eluent conduit. A portion of the inner lip is broken away to facilitate directing the eluent to flow through the aperture. Rotating the insert varies the amount of the broken away portion in contact with the downward flowing eluent which in turn regulates the amount of eluent flow through the aperture.
    Type: Grant
    Filed: November 17, 1977
    Date of Patent: January 15, 1980
    Assignee: Mineral Deposits Limited
    Inventor: Philip J. Giffard
  • Patent number: 4157957
    Abstract: A splitter assembly is described of the type wherein a pulp stream is discharged from the discharge edge of a stratification surface across a gap to impinge against a splitter so as to separate into upper and lower flow components, the lower component passing through the gap while the upper component flows over the splitter, characterized in that the splitter has a generally curved impingement surface and is adjustable relative to the stratification surface such that the gap width in the direction of stream flow increases as the required lower flow component increases and decreases as the required lower flow component decreases. Preferably, the splitter is hingedly mounted for rotation relative to the stratification surface.
    Type: Grant
    Filed: February 10, 1978
    Date of Patent: June 12, 1979
    Assignee: Mineral Deposits Limited
    Inventor: Philip J. Giffard
  • Patent number: 4152257
    Abstract: A wet gravity concentration apparatus with means to divide two streams into four streams of different concentration and means to combine the two streams of intermediate concentration. Two conical concentrators are arranged with a first richer stream flowing over one conical surface and a second poorer stream, flowing over the other conical surface. Each surface has a splitter to separate the stream into a concentrated substream rich in value particles and a less concentrated substream composed primarily of tailings. The richer substream of the second poorer stream is combined with the less concentrated substream of the first richer stream so there are three resulting streams. A deflector can be used to combine the two intermediate substreams.
    Type: Grant
    Filed: November 21, 1977
    Date of Patent: May 1, 1979
    Assignee: Mineral Deposits Limited
    Inventor: Philip J. Giffard