GB1297275A - - Google Patents

Abstract

1297275 Tobacco separator HAUNIWERKE KORBER & CO KG 18 May 1970 [26 June 1969] 23963/70 Heading B2H A tobacco separator for pneumatically separating tobacco ribs from a mixture of tobacco leaf portions and tobacco ribs comprises two separating chambers 8, 9, Fig. 1, arranged one above the other and connected by two ducts 12, 13, and a tobacco accelerating means 27 which is provided in, or in the region of, the mouth of a tobacco mixture feed device 2 leading into the lower separating chamber 9 to throw the tobacco mixture across the chamber 9 transversely to a separating air current flowing therethrough whereby the light tobacco leaf portions are carried with the air current into the upper separating chamber 8 substantially via the duct 12 and heavy tobacco constituents, e.g. ribs with attached leaf portions, entrained in the air current into the upper chamber 8 are returned therefrom to the lower chamber 9 via the duct 13, the accelerating means 27 being arranged in relation to the duct 13 in such a manner that it projects the returning tobacco constituents again across the chamber 9 transversely to the separating air current. The ducts 12, 13 are defined between the walls of the tobacco separator and a pivotable' guide body 11. The chambers 8, 9 and the ducts 12, 13 are bounded by adjustable walls 14, 16, 17. The feed device 2 comprises a belt 23, a metering cell wheel 24 and an angularly adjustable chute 26. The accelerating means takes the form of a winnower roll 27 which, on throwing the tobacco mixture across the chamber 9, also effects a preliminary separation of the relatively heavy ribs which fall downwardly in the direction of the arrows 58. A fan 6 sucks air from the upper separating chamber 8 through an extractor 3 which separates the tobacco leaf portions from the air, and through a pipe 33 and forces air back into the lower operating chamber 9 via a pipe 36, air feeders 37, 38 and perforated walls 14, 16 of the lower chamber. An auxiliary air flap 34 is provided in the pipe 33 to compensate air losses and a restriction valve 39 is fitted in the pipe 36 for adjusting the amount of air. A branch pipe 41 connected to the pipe 36 upstream of the valve 39 and fitted with a further restriction valve 32 leads to a dust filter 4 for extracting dust from the circulating air current. The amount of air supplied through the air feeder 38 is less than that supplied through the air feeder 37 and flows mainly from the chamber 9 through the duct 13 into the chamber 8 whereby a pressure difference is produced at the mouths of the ducts 12, 13 inducing the heavy tobacco constituents entrained into the chamber 8 to seek the path of lower resistance and fall through the duct 13 back into the chamber 9 in the direction of the arrow 61. In a modification, Fig. 2, the accelerating means take the form of a pneumatic nozzle 128 pivotably adjustable about a spindle 129 and connected to a compressed air supply via a valved pipe 132.