LOCK Russian patent published in 2007 - IPC B03B5/70 

FIELD: the invention refers to mining industry and may be used at open extraction of gravel deposits and at concentration of minerals.

SUBSTANCE: the lock for gravitational concentration of gold-bearing sands has an inclined chute of a square form with parallel sides and a catching surface in the shape of rubber porous rugs and metallic stencils. The head of the lock is provided with chutes with changing cross-section, from trapeziform to square, on whose bottom there are rectangular openings. The rectangular chute is fulfilled in the shape of an upper tray for removal from the concentration process of particles whose dimensions are larger then the dimensions of the rectangular openings of the chutes of the head and a low tray on which the catching surface for deposition of other particles passed through the rectangular openings is laid.

EFFECT: increases effectiveness of gravitational concentration of gold-bearing sands.

2 dwg