Method and apparatus for separating granular goods

Claim 2

In a method of separating granular goods of different specific gravity, wherein the granular goods are separated, by a forced air flow therethrough while the goods are on a goods support subjected to a vibration, into a layer of heavier fractions and a layer of lighter fractions, the layers are separated, and the layers are separately discharged: the improvement comprising the steps of, in advance of charging the granular goods onto the support, pre-sorting the goods into a bottom layer, enriched with the heavy fractions, and a superposed layer, free of the heavy fractions; subsequently flowing the layered pre-sorted material onto the support as a continuous current, with at least the layer enriched with heavy fractions having a laminar flow; on the support, separating the two layers to flow along the support in substantially opposite respective directions; and separately discharging each layer.

Claim 3

In a method of separating granular goods of different specific gravity, the improvement claimed in claim 1, including the step of conducting the continuous current along a laterally confined path which is coplanar with the goods support.

Claim 4

In a method of separating granular goods of different specific gravity, the improvement claimed in claim 1, including subjecting at least one of the fractions to substantially a reversal in flow direction when charged onto the goods support.

Claim 5

In a method of separating granular goods of different specific gravity, wherein the granular goods are separated, by a forced air flow therethrough while the goods are on a goods support subjected to a vibration, into a layer of heavier fractions and a layer of lighter fractions, the layers are separated, and the layers are separately discharged: the improvement comprising the steps of, in advance of charging the granular goods onto the support, pre-sorting the goods into a bottom layer, enriched with the heavy fractions, and a superposed layer, free of the heavy fractions; maintaining such superposed relation while subsequently charging the two layers onto the goods support; the layered pre-sorted material being flowed onto the support as a continuous current, with at least the layer enriched with heavy fractions having a laminar flow; conducting the continuous current along a laterally confined path which is coplanar with the goods support; and laterally discharging at least a part of the superposed layer, free of the heavy fractions, from the path onto the goods support in advance of the discharge end of the path.

Claim 6

In a method of separating granular goods of different specific gravity, wherein the granular goods are separated, by a forced air flow therethrough while the goods are on a goods support subjected to a vibration, into a layer of heavier fractions and a layer of lighter fractions, the layers are separated, and the layers are separately discharged: the improvement comprising the steps of, in advance of charging the granular goods onto the support, pre-sorting the goods into a bottom layer, enriched with the heavy fractions, and a superposed layer, free of the heavy fractions; maintaining such superposed relation while subsequently charging the two layers onto the goods support; the layered pre-sorted material being flowed onto the support as a continuous current, with at least the layer enriched with heavy fractions having a laminar flow; conducting the continuous current along a laterally confined path which is coplanar with the goods support; and laterally discharging at least a part of the superposed layer, free of the heavy fractions, from the path onto the goods support in advance of the discharge end of the path.

Claim 7

In apparatus for separating granular goods of different specific gravity, and of the type including an inclined gas-permeable goods support, means directing a gas current upwardly through the support, an outlet for the heavy fractions at one end of the support, a discharge device for the light fractions At the other end of the support, the support having a gradient which descends from the outlet to the discharge device and being vibrated in a direction opposite to the descending gradient, and a goods feeding device discharging onto the goods support: the improvement comprising, in combination, a vibrating duct, having a gas-permeable bottom and a discharge mouth, included in said feeding device; means directing a gas current upwardly through said gas-permeable bottom; said duct forming an initial sedimentation path of the heavy fraction of the fed goods, and along which path the goods are pre-sorted into a bottom layer, rich with the heavy fractions, and a superposed layer, free of the heavy fractions; said duct mouth discharging the goods onto said goods support intermediate the upper and lower ends of said goods support; the portion of said goods upport between said duct discharge mouth and said outlet forming a succeeding sedimentation path for the heavy fraction of the goods charged onto said goods support; said duct mouth being coplanar with said goods support.

Claim 8

In apparatus for separating granular goods of different specific gravity, and of the type including an inclined gas-permeable goods support, means directing a gas current upwardly through the support, an outlet for the heavy fractions at one end of the support, a discharge device for the light fractions At the other end of the support, the support having a gradient which descends from the outlet to the discharge device and being vibrated in a direction opposite to the descending gradient, and a goods feeding device discharging onto the goods support: the improvement comprising, in combination, a vibrating duct, having a gas-permeable bottom and a discharge mouth, included in said feeding device; means directing a gas current upwardly through said gas-permeable bottom; said duct forming an initial sedimentation path of the heavy fraction of the fed goods, and along which path the goods are pre-sorted into a bottom layer, rich with the heavy fractions, and a superposed layer, free of the heavy fractions; said duct mouth discharging the goods onto said goods support intermediate the upper and lower ends of said goods support; the portion of said goods upport between said duct discharge mouth and said outlet forming a succeeding sedimentation path for the heavy fraction of the goods charged onto said goods support; said duct mouth being coplanar with said goods support.

Claim 9

In apparatus for separating granular goods of different specific gravity, the improvement claimed in claim 5, in which the discharge direction of the duct mouth is opposite to the direction of the descending gradient extending from said outlet to said discharge device.

Claim 10

In apparatus for separating granular goods of different specific gravity, the improvement claimed in claim 5, in which the discharge direction of said duct mouth extends at an angle of not more than 90* to the direction of the descending gradient from said outlet to said discharge device.

Claim 11

In apparatus for separating granular goods of different specific gravity, the improvement claimed in claim 5, in which said duct has at least one side wall separating the duct from the good support; said one side wall being formed with an overflow opening whose lower edge is spaced above the goods support, said overflow opening discharging toward the goods support.

Claim 12

In apparatus for separating granular goods of different specific gravity, the improvement claimed in claim 5, in which said duct forms part of said gas-permeable goods support and is bounded by side walls on said support.

Claim 13

In apparatus for separating granular goods of different specific gravity, the improvement claimed in claim 5, in which said gas-permeable bottom of said duct has a gradient rising toward said outlet at least in a front region adjacent said duct mouth.

Claim 14

In apparatus for separating granular goods of different specific gravity, the improvement claimed in claim 10, in which said gas-permeable bottom of said duct has a descending gradient between the goods receiving end of said duct and said front region.

Claim 15

In apparatus for separating granular goods of different specific gravity, the improvement claimed in claim 5, in which said duct mouth is spaced from said discharge device by at least the length of said succeeding sedimentation path.

Claim 16

In apparatus for separating granular goods of different specific gravity, the improvement claimed in claim 5, including a casing enclosing said goods support and said vibrating duct; said means directing gas upwardly through said support opening into said casing beneath said support; a hood closing said casing above said goods support; and gas exhaust means opening through said hood.

Claim 17

In apparatus for separating granular goods of different specific gravity, the improvement claimed in claim 13, in which said goods support with said duct is fixedly connected with said casing along its peripheral edges.

Claim 18

In apparatus for separating granular goods of different specific gravity, the improvement claimed in claim 14, in which said goods feeding device extends along one side of said goods support and substantially parallel to the gradient of said goods support; said casing having side walls; one side wall of said duct being formed by a side wall of said casing, and the other side wall of said dUct being formed by a partition.

Claim 19

In apparatus for separating granular goods of different specific gravity, the improvement claimed in claim 14, in which said duct is covered by said hood.

Claim 20

In apparatus for separating granular goods of different specific gravity, the improvement claimed in claim 13, in which the exhaust opening through said hood comprises a tubular collar; a sleeve connected to said collar and communicating therewith, said sleeve extending laterally from said collar; and means selectively operable to close said sleeve.

Claim 21

In apparatus for separating granular goods of different specific gravity, the improvement claimed in claim 13, in which said hood includes a transparent portion at least in the range of said outlet.

Claim 22

In apparatus for separating granular goods of different specific gravity, the improvement claimed in claim 5, including a blast nozzle in the range of said outlet and directing a gas blast in the direction of the descending gradient of said goods support and substantially parallel to said goods support.

Claim 23

In apparatus for separating granular goods of different specific gravity, the improvement claimed in claim 5, in which said goods support comprises a screen; and a perforated plate beneath said screen and extending in spaced parallel relation thereto and controlling the gas velocity through said goods support.

Claim 24

In apparatus for separating granular goods of different specific gravity, the improvement claimed in claim 20, including baffles extending between said screen and said perforated plate and bonded to each thereof, said baffles sub-dividing the surface of said screen into panels.

Claim 25

In apparatus for separating granular goods of different specific gravity, the improvement claimed in claim 5, in which said goods support has side walls converging from said discharge device toward said outlet; said duct extending intermediate said side walls parallel to the longitudinal center line of said goods support; and a wedge on said goods support between said duct and said outlet, the tapered end of said wedge facing said duct mouth.

Claim 26

In apparatus for separating granular goods of different specific gravity, the improvement claimed in claim 22, in which said goods support has a plane of symmetry; said duct and said wedge being positioned symmetrically with respect to the plane of symmetry of said goods support.

Claim 27

In apparatus for separating granular goods of different specific gravity, the improvement claimed in claim 23, including respective outlets each in the range of the intersection of a respective wedge flank with a respective side wall of said goods support.

Claim 28

In apparatus for separating granular goods of different specific gravity, the improvement claimed in claim 22, in which each of said converging side walls forms, with a normal to the longitudinal center line of said goods support, an angle whose tangent is at least equal to 1.8, both angles being equal to each other.

Claim 29

In apparatus for separating granular goods of different specific gravity, the improvement claimed in claim 22, in which the included angle of the flanks of said wedge is equal to twice the angle of inclination of each side wall of said goods support.

Claim 30

In apparatus for separating granular goods of different specific gravity, the improvement claimed in claim 5, in which said goods support has lateral boundries extending from said discharge device toward said outlet, said lateral boundaries forming, with the normal to the longitudinal center line of said support, an angle whose tangent is at least equal to 1.8.

Claim 31

In apparatus for separating granular goods of different specific gravity, the improvement claimed in claim 27, in which the tangent of said angle is between 2 and 3.

Claim 32

In apparatus for separating granular goods of different specific gravity, and of the type including an inclined gas-permeable goods support, means directing a gas current upwardly through the support, an ouTlet for the heavy fractions at one end of the support, a discharge device for the light fractions at the other end of the support, the support having a gradient which descends from the outlet to the discharge device and being vibrated in a direction opposite to the descending gradient, and a goods feeding device discharging onto the goods support: the improvement comprising, in combination, a vibrating duct, having a gas-permeable bottom and a discharge mouth, included in said feeding device; means directing a gas current upwardly through said gas-permeable bottom; said duct forming an initial sedimentation path of the heavy fraction of the fed goods, and along which path the goods are pre-sorted into a bottom layer, enriched with the heavy fractions, and a superposed layer, free of the heavy fractions; said duct mouth discharging the goods onto said goods support intermediate the upper and lower ends of said goods support in the form of said two layers maintained in such superposed relation; the portion of said goods support between said duct discharge mouth and said outlet forming a succeeding sedimentation path for the heavy fraction of the goods charged onto said goods support; said duct mouth being coplanar with said goods support; a casing enclosing said goods support and said vibrating duct; said means directing gas upwardly through said support opening into said casing beneath said support; a hood closing said casing above said goods support; and gas exhaust means opening through said hood; said goods support with said duct being fixedly connected with said casing along its peripheral edges; said goods feeding device extending along one side of said goods support and substantially parallel to the gradient of said goods support; said casing having side walls; one side wall of said duct being formed by a side wall of said casing, and the other side wall of said duct being formed by a partition; said partition extending to said duct mouth, and being formed with an overflow port between said duct mouth and said discharge device.

Claim 33

In apparatus for separating granular goods of different specific gravity, and of the type including an inclined gas-permeable goods support, means directing a gas current upwardly through the support, an ouTlet for the heavy fractions at one end of the support, a discharge device for the light fractions at the other end of the support, the support having a gradient which descends from the outlet to the discharge device and being vibrated in a direction opposite to the descending gradient, and a goods feeding device discharging onto the goods support: the improvement comprising, in combination, a vibrating duct, having a gas-permeable bottom and a discharge mouth, included in said feeding device; means directing a gas current upwardly through said gas-permeable bottom; said duct forming an initial sedimentation path of the heavy fraction of the fed goods, and along which path the goods are pre-sorted into a bottom layer, enriched with the heavy fractions, and a superposed layer, free of the heavy fractions; said duct mouth discharging the goods onto said goods support intermediate the upper and lower ends of said goods support in the form of said two layers maintained in such superposed relation; the portion of said goods support between said duct discharge mouth and said outlet forming a succeeding sedimentation path for the heavy fraction of the goods charged onto said goods support; said duct mouth being coplanar with said goods support; a casing enclosing said goods support and said vibrating duct; said means directing gas upwardly through said support opening into said casing beneath said support; a hood closing said casing above said goods support; and gas exhaust means opening through said hood; said goods support with said duct being fixedly connected with said casing along its peripheral edges; said goods feeding device extending along one side of said goods support and substantially parallel to the gradient of said goods support; said casing having side walls; one side wall of said duct being formed by a side wall of said casing, and the other side wall of said duct being formed by a partition; said partition extending to said duct mouth, and being formed with an overflow port between said duct mouth and said discharge device.

Claim 34

In apparatus for separating granular goods of different specific gravity, the improvement claimed in claim 29, in which said over flow port has a bottom rectilinear edge inclined downwardly, in a direction toward said outlet, relative to said goods support.