Patent GB-1253531-A (GB)
Title: Cigar bunches
Inventor: SARGROVE JOHN ADOLPH
IPC: A24C1/02
Filed: 1968-03-06
Abstract: 1,253,531. Cigar-making machines. IMPERIAL TOBACCO GROUP Ltd. 10 Feb., 1969 [6 March, 1968], No. 10772/68. Heading A2C. [Also in Division G4] Cigar bunches are made by a method comprising the preparation of a charge of filler tobacco that falls short of a desired or target weight, determining the amount by which the charge falls short of that weight, and supplying an amount of topping-up tobacco proportional to the difference between the target and actual weights. A supply of filler tobacco fed from a hopper (not shown) to a magazine 10, Fig. 1, through a trap door 80, is compressed by a weight 12 and urged into a volumetric measuring channel 20 in a rotatable cylinder 18. The base of the channel, defined by a block 21, rises to a peak at its mid-point between the ends of the cylinder, and the bottom of the weight 12 is correspondingly shaped to distribute tobacco towards the ends of the channel to promote greater density at the ends of the cigar bunches. Actuation of an air motor 37 rotates the cylinder 18 anti-clockwise through a rack 36 and pinion to cause a cutter bar 40 to isolate a volume of filler tobacco which is then deposited in a weigh-pan 50 carried by arms 53 hinged at 39 and carrying a masking plate 54 coacting with apertures 55a, b, c and 56a, b, c. The arms 53, which are clamped at 60' when not performing a weighing operation, are preset to be in balance. with none of the apertures obturated, when the tobacco in pan 50 has a predetermined weight which is less than the target weight. The apertures 55a, b, c are obturated successively in response to one, two or three units overweight with respect to the predetermined weight, and the apertures 56a, b, c in response to one, two or three units underweight. After the weighing the pan 50 is turned by an air jet 61 acting on a vane 60 to discharge the tobacco onto an apron 13. A pan-restoring air jet 59 may be provided. A supplementary quantity of tobacco from a "fines" hopper 82 is delivered by a chambered wheel 83 to make up the target weight. Each chamber of the wheel 83 contains one unit weight of tobacco so that if, e.g. the predetermined weight for which the pan 50 is set is three units less than the target weight and a quantity of tobacco weighed by the pan is one unit over the predetermined weight, the wheel 83 is caused to turn an amount corresponding to two chambers to make up the target weight. On completion of delivery, the tobacco on the apron 13 is swept towards a plate 71 by a plate 74 operated by an air motor 76 and the entire delivery apparatus is raised to permit bunch rolling on the table 14. Associated with each aperture 55a, b, c and 56a, b, c is a photocell connected to a series of holding circuits 90, Fig. 3, which feed into an algebraic summing unit 91 the purpose of which is to control a motor 33 to provide a corrective adjustment of the depth of channel 20 by an eccentric 24 influencing the position of the block 21 whenever the algebraic sum of the signals from the photo-cells exceeds a certain value, e.g. five units, thereby eliminating any trend in the deliveries from channel 20 away from the predetermined weight for which the pan 50 is set. The signals from the holding circuits 90 are also fed to digital command circuits 95 which, through a decoder 97, binary counter 100, and oscillator 101 control stepwise operation of a motor 84 to deliver the required number of units of topping-up tobacco. A switch 106 coacting with a cam-wheel 107 ensures that the movements of the motor 84 are synchronized with the pitch of the chambers in the wheel 83.