Patent GB-248260-A (GB)
Title: Improvements in machine and process for blending and stripping tobacco
IPC: A24B5/10
Filed: 1925-08-18
Abstract: 248,260. Croad, A. K., (American Tobacco Co.). Aug. 18, 1925. Tobacco.-In means for stripping tobacco, the tips of the leaves are first cut off, and the remaining portions afterwards subjected to a series of disintegrating operations, buoyant particles being winnowed out between successive operations and the heavier particles discharged by gravity at regular intervals. Tobacco leaf from piles 7, Fig. 2, of various grades, according to the blending desired, is placed in bunches upon a belt 1 and thereby conveyed to a pair of belts 9, between which is arranged a disc cutter 14 so as to cut the leaves in two, the tip portions passing away by a conduit 11 and conveyer 195. The leaves are held on the belts 9 by a pair of slack endless chains moving over the top of the belts. The stem ends of the leaves are carried by a conduit 10 to a disintegrator D, Fig. 3, preferably on a floor below and comprising a rotating cylinder 25 having teeth 24 co-operating with teeth 23 on a concave 22. The lighter leaf particles are driven by a fan 36 against an endless-belt screen 40 and delivered on to a conveyer 54, a rotary brush 42 sweeping the leaves from the belt 40. The conveyer 54 delivers to another conveyer 57 leading to the conveyer 195. The heavier leaf particles fall on to a conveyer 49 and are carried to a series of further disintegrators E, F, G of the same construction, but with the teeth of each disintegrator arranged closer together than those of the preceding one. Each fan 36 has its axial inlet regulated by a damper 62, and the blast is further regulated by louvres 73. The fine particles of tobacco and dust are forced through a tangential outlet and pipes 66 or 69 to dust collectors 67 or 68. The heavier particles from -the disintegrator G are led by its conveyer 49 to another disintegrator H, Fig. 8, having two toothed cylinders 79, 81 co-operating with concaves 80, 82. From these, the leaves pass over a bridge 102 on to an oscillating riddle 91 provided with screens 99, 100, 101 of decreasing mesh. The two upper screens deliver to a trough 104, from which the leaf particles are driven by a fan 106 through an outlet 107, the stem portions falling into a hopper 111 and a collector on a lower floor. The outlet 107 is provided with a perforated arch 128, through which and through a conduit 123 the finer particles and dust are with drawn by an air pump 124, Fig. 2, and led by a conduit 125 to the dust collector 67. A similar conduit 122, Fig. 8, connected to the conduit 123 serves to withdraw dust &c. from the disintegrator casing 77. Leaves passing through the outlet 107 are carried by a conveyer 131 back to the disintegrator F and treated again. The lowest screen 101 delivers to a trough 116 which has a lateral outlet, through which the leaves fall on to a bucket conveyer 148, Fig. 2, and are thereby carried on to a single oscillating screen 155. The particles passing through this screen are discharged laterally into a receptacle, while those unable to pass through arecarried by a fan into a conduit 165, which has. a gravity discharge of the heavier portions intoa collector, the lighter portions being carried over to the conveyer 57 by a pipe 199. Theparticles falling through the screen 101, Fig. 8, fall through a pipe 117 into a receptacle. In the collectors 67 and 68, Fig. 2, the dust is carried upwards through conduits 70, while the tobaccofragments are discharged through pipes 71, 72 on to an oscillating screen 177 comprising threetiers similar to that shown in Fig. 8. The leaf portions from this screen are delivered on to a conveyer 187 discharging on to the conveyer 57, whereas the stem particles which pass through, all the screens are delivered into a receptacle. The screens are supported by resilient links 92, Fig. 8, fixed at one end to the supporting-frame and pivoted at the other end to the screens, which are oscillated by an eccentric 95 and rod 96.