PNEUMATIC SEEDING UNIT Russian patent published in 2003 - IPC

FIELD: agricultural engineering. SUBSTANCE: pneumatic seeding unit has thin- walled hollow drum adjoining to hopper. Drum surface is provided with through suction openings. Drum sides are mounted on hollow spindle of rotation, which in conjunction with openings defines air duct for discharging air from drum cavity under the action vacuumizing effect. Bracket is rigidly fixed on air duct. Rotary frame pivotally connected with bracket is adapted for attachment of shielding roller provided with flexible cover. Double-cavity pneumatic chamber is located in drum and rigidly fixed on hollow spindle and connected through stem and pivot joint to rotary frame cross-member. Pneumatic chamber membrane is spring-loaded in stem cavity, which is communicated with drum cavity and with vacuumizing cavity of three-cavity pulsator. Cavity free of stem is connected through air ducts with pulsator working cavity. Pulsator pressure cavity is communicated with atmosphere. Pulsator is driven in coordinated manner by drum. EFFECT: enhanced reliability in operation and improved quality of seed sowing. 1 dwg