Patent GB-692107-A (GB)
Title: Improvements in classifying apparatus for sand commonly called sand cones
Inventor: DRIGENKO CONSTANTINE
IPC: B03B5/60
Filed: 1950-09-05
Abstract: 692,107. Gravity-separation apparatus. FLOATEX SEPARATIONS, Ltd., and DRIGENKO, C. Aug. 24, 1951 [Sept. 5, 1951], No. 21892/50. Class 46 in apparatus for separating sand or other granular material from water comprising an inverted cone 1, Fig. 1, in which the solid material collects for continuous or periodical discharge through a valve 18 at the bottom while the excess water continuously overflows an edge 14 at the top, and in which the degree of opening of the valve 18 is adjusted in response to the pressure of the suspension of sand in water at the inlet, the pressure at the irilet -itself varying in accordance with the level of deposited sand in the cone which chokes the flow of suspension to a varying degree, the mechanism for adjusting the degree of opening of the discharge valve comprises a tank 27 which is movable up and down to actuate the discharge valve 18, is provided with a metering orifice 28 in its base, and is supplied with liquid at a rate dependent or the pressure at the inlet of the cone 1, a stationary restrictor 36 projecting into the metering orifice 28 being tapered to permit an increasing or decreasing outflow of liquid as the tank falls or rises respectively. The cone 1, which is supported by fixing brackets 2, is provided wth an inner shell 3 tapering slightly inwards towards its lower edge and carrying a short toothed portion 4 of greater degree of taper, the shell 3 being attached to the cone 1 by an annular partition 5 forming an inlet chamber 6 and overflow channel 7. The suspension enters chamber 6 by a tangential inlet 100, excess water overflowing an adjust-' able edge 14 and a ring 15 communicating by radial pipes 16 with the channel 7. When the level of sand rises above the lower edge of portion 4, water rises from chamber 6 up a connecting duct 31 and overflows a weir plate 33 into a bleeding tank 32 mounted on the side of the cone, the weir plate having an aperture whose width varies inversely as the square root of the height from the lower edge of the aperture so that the flow into tank 32 is proportional to the head of water in duct 31 above the overflow edge 14. Tank 32 discharges through pipe 34 and horizontal outlets 35 into the tank 27 which is supported by a pair of links 26 from a lever 20 pivoted in ball-bearings 21 supported at the centre of a bridge 12. The resulting downward movement of tank 27 further opens the valve 18, which is suspended from lever 20 by rod 17, equilibrium being established by a greater flow of liquid through orifice 28 into tube 29 and waste pipe 30. Counterweights are placed on rod 23 attached to lever 20, holes 24 being provided to receive a stop pin which by abutting a bracket 25 limits closing movement of the valve 18 to prevent damaging its rubber facing 19. A tube 8, surrounding rod 17, is supported by bracket 13 from the bridge 12 and carries a conical member 9 having vanes 10 secured by straps 11, the members 9, 10 preventing a vortex occurring on discharge. In a modification, Fig. 2, in which the tank 27 and its associated parts does not act directly on the valve but acts through an amplifying device, the interior of the cone 1 is constructed as in Fig. 1. On the level of sand rising in the cone, liquid passes from chamber 6 through duct 31 to a weir tank 40, overflowing weir plate 33 and passing through pipe 34 into the tank 27 which is suspended by a pair of slings 26 from one end of an inner double lever 44 pivoted on a beam 41 spanning the cone. The resulting downward movement of the tank 27 rocks lever 44, which is counterbalanced at 46, causing a hollow cylindrical restrictor 58, which is hung from lever 44 by a suspension 59, to move downwardly within a canister 50, a similar restrictor moving upwardly within a corresponding canister 62. Since water supplied to canisters 50, 62 from a gutter tank 39, Fig. 3, through pipes 53, volutes 54 and pipes 55 can only escape to waste at 52 through the available portions of slots 61 in the restrictors 58, the movement cf the restrictors causes the canisters 50, 62, which are suspended by slings 49 from opposite ends of an outer lever 45 pivoted coaxially with lever 44, to become unbalanced. Canisters 50, 62, consequently move downwards, and upwards respectively, valve operating rod 17 which is carried by lever 45 thus being mcved downwardly to open the valve. Gutter tank 39 receives the overflow from weir 14 through channel 7 and from an overflow through pipes 38, the level in tank 39 being controlled by a hollow cylindrical valve 65 sliding in a waste pipe 64 and fixed at a variable height by bar 66. Since to prevent jamming of the restrictor 36 in orifice 28 some clearance must be provided, a small bleed may be provided by a pipe 68 from inside the cone through valve 69 to supply the additional flow. In further modifications the canisters are not equidistant from the lever pivot, and the canister 62 and associated parts may be replaced by a counterweight. According to the Provisional Specification the restrictors may be conical. Also in a further form of hydraulic amplifier described therein, the two canisters are fed from opposite sides of a central partition in a cylindrical collector mounted on the side of the cone. The' quantity of overflow from the cone which passes into each side of the collector is determined by a pivoted relay, the relay consisting of a cylindrical body open at the top to receive the overflow and having a semi-circular opening bounded by a diametral vertical 'wall at its lower end. A cord passed round the relay and over pulleys has a tank constituting the hydraulic pre-amplifier at one end and a balancing weight with a pair of stabilizing chains attached thereto at the other. In a further form, the hydraulic relay carriers a flange nearly midway of its height. A ring channel surrounds the relay and is freely rotatable within limits by means of the cord attached to the pre-amplifier tank. A transverse pivot spindle on the relay carries lever arm coupled to the ring channel. The inner end of the spindle carries a vertical fin which is in the flow of water discharged into the relay. Consequently a change of sand level in the cone causes movement of the ring channel and tilting of the fin and the flow of water drives the cylindrical relay member to adjust the opening and closing of the valve as before. Specification 634,226 is referred to.