An improved grinder for the cutting knife of a cigarette machine cut-off

摘要

1,010,835. Grinding. MOLINS ORGANISATION Ltd. Nov. 19, 1964 [Nov. 20, 1963], No. 45816/63. Heading B3D. [Also in Division A2] A cigarette-machine having a cut-off consisting of a flat-knife 12 which has a cutting edge eccentric to the axis of rotation of the knife and is traversed at substantially the speed of a cigarette rod CR in the machine by a mechanism, such as a Hooke's joint, which causes the knife to be substantially at right angles to the rod during the cut and at a position 180 degrees therefrom, has a grinding device for the knife comprising a grinding wheel 37 having a cylindrical, frusto-conical, paraboloidal or barrel shape, the grinding wheel being situated to be in contact with the midpoint b of the edge of the knife when that point is 180 degrees from the axis of the cigarette rod and with its axis 38 in a plane containing said point of contact and the axis of the cigarette rod, and means mounting the grinding wheel for rotation about its axis and for adjustment of its axis about the point of contact to grind a chamfer along the length of the edge for different cigarette lengths. The cigarette machine has a tobacco filler held on the underside of a conveyer band 2 by a suction chamber 3. A continuous wrapper 5 is wrapped around the filler by a folding device 6 and has its edges gummed by a pasting device 7 and dried by a heater 8. The continuous rod is passed to a cut-off mechanism 9, the cut pieces then passing to the flutes of a drum 10 and a band 11. The cut-off mechanism comprises the flat knife 12 which is carried by member 19 mounted by a pivot 23 on the end of a shaft 13 driven from a gear-box 14. The members 19 are also connected by pivots 34, 35 to a block 20 mounted on a shaft 15, the members 19, 20 with their pivots forming a Hooke's coupling between the shafts 13, 15. Shaft 15 has its end mounted in a shoe 16 which can be adjustable along a curved guide 17 to vary the traversing movement of the knife relative to the movement of the cigarette rod, which moves at a constant speed, to cut longer or shorter cigarettes, the speed of rotation of the knife also being varied. The rod is supported during cutting by aledge 21 having three tubes 21a, 216, 21c reciprocated in the direction of the rod movement by a crank 22 driven from the gear-box 14. The grinding wheel is located 180 degrees about the shaft 13 from the cigarette rod and is supported in a housing 41 with its axis in the plane of the axis of the shaft 13, the wheel engaging the knife edge at its mid-point b in that plane. The housing is mounted for adjustment about the mid-point on a bracket 42 secured to the gear-box to grind chamfers of the knife edge corresponding to the length of rod to be cut, the adjustment being facilitated by engaging a selected notch 43A on a disc 43 mounted on the housing with a pin 44 on the bracket. The knife is fed outwardly in a gradual manner to compensate for wear by a mechanism such as described in Specification 973,620 and is deburred after passing through the rod by a de-burring wheel 40. The grinding device may be incorporated in a machine for cutting filter plugs.