GB945839A - Method and apparatus for producing a continuous tobacco rod - Google Patents

Abstract

945,839. Cigarette-making machines. K. KÍRBER. April 12, 1960 [July 18, 1959], No. 13028/60. Heading A2C. [Also in Division G3] In a method for equalising or levelling a tobacco stream in which inequalities are removed from the upper surface of the tobacco stream, both the equalised tobacco rod and the unequalised tobacco stream from the distributer are measured, the two measurement values are compared and a modification of the trimming plane is effected until the difference of the two measurements is zero. As shown, a cigarette rod-making machine comprises a distributer 1, a receiving belt 2, a forming wheel 3 consisting of a primary wheel 4 with a suction groove and a secondary wheel 5 with a groove having a carded surface at its base, a trimming device 6, a forming belt 7 and rod-forming mechanism 8. A guide duct 9 transfers tobacco withdrawn by the trimming device to the secondary wheel 5. A carding roll 10 picks the tobacco off the secondary wheel 5, which rotates more slowly than the primary wheel to provide a minor tobacco stream of manageable crosssection, and spreads it on to the tobacco stream on the belt 2. By this arrangement the tobacco stream carried by the belt 2 is underlaid by the minor stream as regards the position at the trimming point. A radiation source and ionisation chamber system 11 measures the tobacco stream coming from the distributer 1 and a similar measuring appliance 12 measures the cigarette rod. The measurements of the two appliances 11 and 12 are supplied to the differential amplifier 15. The output measurement of the differential amplifier 15 is supplied to the control device 17 for regulating the upward and downward movement of the trimming device 6 and this raises or lowers the trimming device 6 until the two measurements correspond. The control impulse from the measuring appliance 12 is utilized both for controlling the distributer and for the difference measurement above. For the control of the distributer the measurement value obtained from the appliance 12 is compared with a standard value. For this purpose the measurement value supplied by the appliance 12 is fed to a control unit 22. If the measurement value received from the appliance 12 differs from the standard value the control unit 22 delivers a control signal to the control unit 19 which alters the speed of the distributor. This in turn alters the measurement value of appliance 11 which will alter the height of the cutting plane so that the measurement value of appliance 12 returns to the standard value.