Patent GB-426858-A (GB)
Title: Improvements in or relating to mechanism for conveying tobacco leaves, particularly for tobacco leaf spreading or stemming machines
IPC: A24B5/12
Filed: 1933-12-02
Abstract: 426,858. Endless-belt conveyers. TRIGGS, W. W., 57, Lincoln's Inn Fields, London.- (International Cigar Machinery Co. ; 5520, 2nd Avenue, Brooklyn, New York, U.S.A.) Dec. 2, 1933, No. 23208/34. Divided out of 425,187, [Group VI]. [Class 78 (i)] [See also Group VI] Mechanism for conveying tobacco leaves, particularly in leaf spreading or stemming machines, comprises two forwarding conveyers arranged with their leaf-supporting portions facing each other, and means for transferring leaves in succession directly from one conveyer to the other across the space between them. The leaves are preferably held against each conveyer by suction, the suction being periodically cut off from the first conveyer and simultaneously applied to the second, and air pressure being applied to the first conveyer to discharge the leaves to the second conveyer. The invention is shown as applied to a leaf opening or spreading mechanism as described in Specification 380,823, [Group VI], associated with a stemming mechanism as described in Specification 380,496, [Group VI]. The leaves to be opened are fed over a table 13 by belts 12 and a chain 15. At the forward end of the table, the butt end of each leaf is lifted by a cam-actuated block 49 and engaged by one of the grippers 46 carried by cross-bars extending between a pair of endless chains 31 travelling on sprockets 30, 41. The grippers carry the leaves, butt end foremost, through the suction chambers 51, 60 of the leaf-opening mechanism, which are connected to suction pipes 53. On leaving the chambers 51, the stem or central portion of the leaf is pressed on the pins of a carded belt 59, and as the tip of a leaf passes from beneath the roller 58, the suction in the chamber 60 is cut off by valves 61 in the pipes 53, to prevent displacement of the tip from central position. The valves 61 are actuated by a rod 62 connected to a lever 63 actuated by a cam 65 on a shaft 35. The roller 58 is carried by an arm 255 on a shaft 256 having an arm 258 connected by a link 260 to a lever 261 actuated by a cam on the shaft 26, the roller 58 being lifted periodically to allow the grippers 46 to pass. The opened leaves emerging from the chambers 60 pass to leaf-conveying mechanism comprising an endless perforated belt 65 on each side of the path of the leaf stems. The belts 67 travel over slotted or perforated suction chambers 68 connected to suction pipes 69. The forward portions 68<1> of the chambers are connected to the pipes 69 by pipes 691 and are continuously maintained under suction, while the remaining portions are connected through pipes 69<11> provided with valves 70 connected through linkage 71 .. 77 to a lever 78 actuated by a cam on the shaft 26, so that suction is periodically cut off. The leaves are received by a perforated belt 98, or a series of chains 132, Fig. 3, travelling over a slotted or perforated chamber 99 connected by pipes 100 to the pipes 69<11>, the valves 70 being arranged at the junction of the pipes 100, 69<11>, so that when the suction is cut off from the chamber 68 it is applied to the chamber 99, and vice versa. At the same time, the grippers 46 are opened by a stationary cam 48 to release the stem, and positive discharge of the leaves from the belt 67 on to the belt 98 by air pressure is effected by a pivoted plate 81, within the chamber 68, actuated by pivoted fingers 83 connected by links 84, 85 to a lever 86 actuated by a cam 87 on a shaft 88. The discharge is assisted by a roller 97 mounted by a rod 101, Fig. 3, carried by bell-cranks 102, 103 connected by links &c., 106.. 116 to a lever 117 actuated by a cam on the shaft 26. The leaves are carried from the belt 98 through the suction chambers 140 of a second spreading mechanism by a belt 137 co-operating with a pair of narrow belts 132 travelling upon the belt 98, and passing around rollers on shafts 134, 135. When chains 131 are employed in place of the belt 98, two of the chains 132, Fig. 3, run on sprockets on the shafts 134, 135. The leaves are thus delivered to stripping mechanism 143, 145, and the stripped leaves are carried by a belt 160 to a leaf conveyer including a perforated belt 230 travelling over a slotted suction chamber 231. The end 231<1> of the chamber is continuously connected by a pipe 232 with one of the suction pipes 69, while the suction in the remaining part of the chamber is cut off periodically by a valve 234, air being admitted by a valve 235 when the suction is cut off. The valves 234, 235 are connected by links 248, 251, arms 247, 250, 242 on a shaft 239', and a link 243 to a lever 244 actuated by a cam on the shaft 88. When the valve 234 cuts off the suction, the leaves are positively discharged from the belt 230 on to a transverse conveyer 252 by the air pressure caused by a plate 237 supported by arms 238 on the shafts 239, 239<1>, which are connected by means of arms 240 and a link 241.