Patent RU-94027943-A (RU)
Inventor: DIBROV V F
IPC: B30B11/02
Filed: 1994-07-25
Abstract: FIELD: mechanical engineering. SUBSTANCE: automatic device for tableting has die, drive of lower punches coaxial to die seats and feeder mounted on bed-plate. Gate valve-batchmeter with drive for its reciprocal motions along upper surface of die is mounted between outlet window of feeder and die. Control members of drives (hydraulic distributors) and transducers are made and are connected with control unit providing for possibility of finding lower punches in positions of dosing and ejection of finished products and of finding the gate valve in positions of charge of its dosing window and charge of die seats. To achieve the above-mentioned advantages upper punches with drive and transducer for fixating these punches in positions of molding and unloading the finished products are mounted on bed-plate above the die coaxial to its seats. In this case all members (body) of gate valve in position of charging its dosing window are disposed outside the zone of die seats. The control unit is made so that it can provide for giving the instruction to switch over the punches into molding position after gate valve-batchmeter accomplishes not less than two complete cycles of reciprocal motions which enhances the uniformity of filling all die seats regardless of their remoteness from feeder. To provide for greater uniformity of filling the seats disposed at different distances from feeder with molding material which accumulates or remains at rear (on the move) border of gate valve window during gate valve displacements, in one variant gate valve window passes above seats and behind them, in another variant the die seats are disposed in one row in the direction orthogonal to line of gate valve displacements. In the third variant grate with ribs of laminated shape is inserted into window. To enhance efficiency (per unit of mass and volume of automatic device) and to expand nomenclature of simultaneously molded articles the members are mounted on bed-plate 1 from free side of feeder symmetrically to first position of molding. The members form second molding position, analogous to first one, with common feeder, control unit and gate valve-batchmeter mirror-extended towards it. The method includes reciprocal motions of gate valve-batchmeter between outlet window of feeder and zone of arrangement of die seats, suction of molding material into seats by punches, molding itself by return (counter) movement of punches and unloading of finished products. It is characterized by the fact that molding is carried out as minimum at two positions symmetrically disposed relative to feeder with utilization of two-window gate valve-batchmeter. In this case molding itself at each position is carried out after the zone of arrangement of die seats is covered by corresponding window of gate valve-batchmeter not less than twice. In one variant molding itself is fulfilled at the beginning of charging phase of seats at neighboring position, in another variant at the end of phase. EFFECT: enhanced efficiency of loose material tableting, enhanced quality of molded tablets (stability and uniformity of density), reduced waste, enhanced mass-overall characteristics. 13 cl, 6 dwg