Patent GB-463583-A (GB)
Title: Improvements in and relating to mechanism for winnowing disintegrated tobacco leaves
IPC: A24B5/10
Filed: 1936-01-31
Abstract: 463,583. Separating solid materials.' INTERNATIONAL CIGAR MACHINERY CO. Jan. 31, 1936, No. 2962. Convention date, Oct. 3, 1935. [Class 117] [Also in Groups VI and XXVI] In mechanism for winnowing disintegrated tobacco comprising a tower having an inlet and an outlet, the inlet being divided into primary and secondary feed channels both communicating with the outlet and means for creating separate currents of air through the channels whereby the lighter portions will be carried upwardly through the channels and delivered to the outlet while the heavier portions falls downwardly and are delivered separately, one or more return channels are provided between the primary and secondary feed channels to conduct the heavier portions in the primary channel into the air passing through the secondary channel. Tobacco leaves L are placed between guides 41 and carried by a belt 14 beneath an adjustablymounted pressure roller 15 into a chamber where the leaves are disintegrated by being carried by spikes 17 on a rotating drum 16 through and against stationary spikes 18 carried by a hinged cover 13. The shreds fall through apertures 46 in a replaceable member 12 on to a perforated belt 47 which carries them to a winnowing tower 11. The upper run of the belt 47 is agitated by beaters 64 to loosen dust and sand which is withdrawn from a chamber 48 beneath the belt by a fan 49. Dust and sand are also removed from the leaves on the belt 14 through a slot 55 in a suction chamber 54 connected to the chamber 48 by a pipe 53. A blower 67 forces the shreds up a primary channel formed between a central partition 68c and the wall of the tower 11, the leaf portions passing over the partition and falling into a receptacle 69 while the stem portions fall down channels between partitions 68c, 68b, 68a, into a secondary channel. The stem portions are forced up the secondary channel by a second stream of air delivered by the blower, the heavy stem devoid of leaf fragments falling down adjustable baffle plates 68d, 68e, into a receptacle 76, while the stem portions having leaf fragments and the curled tip portions falls down a, duct 77. Any leaf fragments in the secondary channel are carried into the outlet of the tower and fall into the receptacle 69. The walls of the primary and secondary channels are corrugated and shaped to provide expanded sections adjacent the ends of the partitions to reduce the air velocity and facilitate the falling of the heavier shreds. To regulate the separating action adjustable regulating gates 70, 70a, are provided at the top of the partitions. To prevent the building up of back pressure the top of the tower 11 is formed by a screen 11b. The curled leaf tips and the stem portions delivered down the duct 77 are fed by a conveyer belt 78 down a shoot 79 on to the belt 14 and forwarded to the disintegrating apparatus. The air currents delivered through nozzles 65, 75 up the primary and secondary channels are supplied by a pair of centrifugal fans mounted on a common shaft 80, Fig. 6, and delivering through a common outlet 66. To control the amount of air admitted to each blower shutters 100 are opened or closed by turning knobs 109 on regulating spindles 107. To vary the air flow through the nozzles 65, 75 either the position of a wedge shaped deflector 89 between the nozzles 65, 75 is adjusted by turning a knob 98 on a spindle 96 or sets of shutters in the nozzles are independently adjusted. In a modified construction the suction fan 49 is dispensed with and the belt 47 is made of imperforate material and dust and sand are removed by surrounding the screen at the top of the tower with a jacket connected to a suction fan. Back pressure in the tower is prevented by providing an adjustable relief valve in the top of the jacket. In another construction the belt 47 is eliminated and the winnowing tower and blower arranged close to the disintegrating mechanism.