SEED CLEANING UNIT Russian patent published in 2003 - IPC

FIELD: agricultural engineering. SUBSTANCE: seed cleaning unit has charging bucket chain for feeding grain heap through divider into pneumatic sieve type grain cleaning machine with air distributing system and sieve shoe having tiered sieves. Grain cleaned from contaminants on sieve shoe is delivered in two individual flows to gravitational chutes for additional cleaning in graders. Lowe part of gravitational chutes is made curved, with radius of curvature equal to 0.85-0.95 the radius of working surface of graders. Lower parts of gravitational chutes are extending tangentially to their working surfaces in direction of rotation of graders. EFFECT: increased efficiency by eliminating impact action upon seeds and, accordingly, reduced damage to seeds. 2 cl, 2 dwg