GB1269573A - Process and device for stemming tobacco leaves - Google Patents

Abstract

1,269,573. Pneumatic separation. SERVICE D'EXPLOITATION INDUSTRIELLE DES TABACS ET DES ALLUMETTES. 25 Feb., 1969 [26 Feb., 1968], No. 10049/69. Heading B2H. [Also in Division A2] In a tobacco stemming and separating device in which leaves pass downwardly through a tube 33 to a beating zone having a three-stage toothed rotor 13, 14, 16 driven by an electric motor 28 and from which the shredded leaf fragments are discharged outwardly past bars 24, 26, 27 to an annular space 31 in which an upward air current carries the fragments into a separation zone 32, the air current is divided by the provision of one or more auxiliary separation zones 44a leading off from the main zone 32. The relatively heavy stem portions of the leaves are discharged from the third stage 16 of the rotor and fall downwardly to be transferred by a rotary gate 38 to a rotary tray 30 for their removal. Any relatively heavy leaf fragments carried upwardly by the air current in the space 31 fall back from the separation zone for further treatment in the heater. The current of air, generated by a fan 42, is supplied to the space 31 through conduits 41, 39, 40 and withdrawn from the zone 32 through a conduit 47 and from the auxiliary zones 44a through conduits 46a &c., all of which join a common discharge conduit 49 leading to a separator 51 from which the tobacco payments are delivered by a rotary gate 52 to a conveyor 53. The air is recirculated by a duct 54 to the fan inlet 57, fresh air being admitted at 56 to compensate for a quantity that is discharged to an outlet 60 by way of a duct 59 and air filter 61. Valves 72a &c. in the conduits 46a &c. may be controlled individually or, as shown, collectively. To prevent the accummulation of tobacco leaf fragments against vertical partitions 66a in the zone 32 due to the rotary component of motion imparted by the beater, air inlets 68 are provided fed by a conduit 65 tapped from the conduit 41. Also fed by the conduit 65 and ducts 64a which supply air to a chamber 34 having openings 67. (For Figures see next page)