PNEUMATIC SEEDING UNIT Russian patent published in 2004 - IPC

FIELD: agricultural engineering, in particular, seeding units for small seed crops drill. SUBSTANCE: pneumatic seeding unit has seed hopper communicated with excessive air pressure source, seed flow synchronizer coupled to drill wheel, agitator communicated with seed hopper through annular gap, distributing device and air ducts. Ejector arranged in seed hopper is composed of ejector air duct and feeding chamber, which is communicated via feeding chamber opening with seed hopper cavity. Section of feeding chamber is controlled by means of diaphragm. Seed hopper is composed of two parts connected with one another through screw-type regulator allowing level of arrangement of ejector above agitator to be regulated and, accordingly, constant specific seeding rate of seeding unit to be provided. Agitator is axially aligned with feeding chamber and is made in the form of hollow cylinder with seed baffling shield and annular shutter positioned on the outside of cylinder. Annular shutter defines in conjunction with seed hopper bottom annular gap. Drop frame mounted onto seed hopper charging opening is made from air-permeable material, such as netted material. Shutters are mounted inside air ducts. Seeding unit of such construction is used for seeding of small seed crops, such as amaranth. EFFECT: uniform seed distribution over seeding area, optimal seeding rate providing formation of herbage having structure enabling stable crop yield, and increased workability of construction owing to absence of movable parts. 4 cl, 1 dwg