Patent GB-733536-A (GB)
Title: Improvements in or relating to rotary automatic machines for shredding tobacco leaves and the like
IPC: A24B7/12
Filed: 1953-08-07
Abstract: 733,536. Tobacco-cutting machine. S.A.S.I.B. SOC. PER AZIONI SCIPIONE INNOCENTIBOLOGNA. Aug. 7, 1953 [April 24, 1953], No. 21911/53. Class 5 (1). [Also in Group XXIII] Tobacco is fed in automatically-regulated amount by the swinging rake 3 of a hopper 1 to upper and lower feed rolls 4, 5, 6 and 7, of which at least one roll 5 coacts with at least two counter rolls 4 and 6 to continue the feed in and through a mouthpiece 8 where it is shredded by a rotating cutter head 27. To take up wear and the effect of continual sharpening by a grinding roll 31 the cutter head 27 is advanced slowly towards the mouthpiece 8 and the grinding roll automatically follows the advance of the cutters. When the swing of the rake 3 about pivot 103, Fig. 9, meets an increasing resistance of the tobacco to compression, the spring 59 not being strong enough to pull the rake 3 completely forward, the cam actuated swinging lever 57 then comes away from its abutment prop 60 which then pivots down by gravity about fulcrum 161 until its end rests somewhere on the inclined surface 157 of lever 57 and until the upper end of balance lever 61 meets an adjustable stop abutment 62. Thus the stroke of the outer swinging lever 56 and the coupled compression rake 3 is lessened whereby compression is reduced. When the diminished compression allows spring 59 to pull 3 to a full swing, the prop 60 can rise up again as 61 is pulled by 59 to pivot about 62. The rotating cutter head 27 is mounted between side support arms 40 which are swingable about a pivot 140 to adjust the cutter to or from the mouthpiece 8. This distance is determined by the pull of a link 50 on the top of lever 40, the amount of pull being determined by the speed of the feed roll 4 which, rotating a worm wheel 43, advances a threaded spindle 44 inside 43. 43 is coupled by a hand-releasable friction lock nut 49 to 46 so that a hinge point 146 is moved whereby the arm 47, pivoted at 146 in conjunction with two side eccentrics 148, determines the movement of link 50 and thus of the knife head 27 towards the mouth 8. Hand release of the friction lock nut 49 and rotation of a handler 144 allows hand adjustment of the cutter head 27 towards or from the mouth 8. Further, the rotation of the feed rolls 4-7 is automatically stopped when the torque required to drive them against a possible increase of compression of the tobacco exceeds a predetermined amount. The roll 6 to which the other rolls are geared is driven by motor 9 and belt through a reducing worm gear 11 driving a shaft 112 from which the roll 6 is driven through another worm shaft. Between the drive from 11 to 112 is an automatic clutch 16, declutchable either by hand lever 17 or automatically as follows. The resistance to rotation of roll 6 &c. creates a corresponding thrust on worm 12 and its shaft 112, Fig. 7, which causes extra compression in a hydraulic cylinder 220. The endwise movement of 112 tends to push the grooves of clutch member 24 out of driving engagement with the grooves of worm wheel 211 and also to slide axially the spindle 26 and so move clutch lever 17. When a predetermined maximum limit of compression of the tobacco has been reached the lever 17 is automatically moved full over to de-clutch the drive to the rolls. The limit is determined by adjusting, by screw nuts, the reaction of a leaf spring 25 to the hydraulic cylinder 220 and thereby determining the movement of the piston 120 therein. The hydraulic compression in the cylinder 220 is shown on a gauge 22 which shows the operator when he may voluntarily operate the clutch lever 17 to stop the drive temporarily or to restart it, or to prevent automatic declutching. A safety breakable pin 25 is interposed in the thrust line between shaft 112 and piston 120. The grinding wheel 31 moves to follow the movement of the cutter head 27 to or from the mouth 8 by means of an adjustable link or abutment prop 53 interposed between the grinder housing 51 and the side arms 40 which impart adjustment to the cutters, the housing 51 pivoting about a pivot 52. The grinding wheel 31 is trued by a suitable block adjusted by a hand screw 55 in the grinder housing 51. The cutters 30 comprise axial or helical blades 30 of steel ribbon or sheet adjustable and clamped as in Fig. 5 (not shown). The mouthpiece 8 has a yielding, e.g. a pivoted, upper lip (108, Fig. 3, not shown) which maintains a definite compression on the tobacco.