Patent GB-929337-A (GB)
Title: Apparatus for measuring a characteristic of a moving filler in a continuous rod machine and recording variations therein
IPC: A24C5/34
Filed: 1958-07-04
Abstract: 929,337. Registering and recording the working of machines; counters. G. F. W. POWELL, F. POCOCK, R. G. CROSLAND, and MOLINS MACHINE CO. Ltd. July 6, 1959 [July 4, 1958], No. 21486/58. Classes 106 (1) and 106 (4). Apparatus for checking a characteristic of cigarettes produced by a continuous-rod cigarette-making machine comprises a gauge 1 for producing electric signals which vary with changes in a filler 2 averaged over a length of filler substantially equal to the length of the cigarettes produced by the machine and means for recording or registering the averaged signals whereby the characteristic (expressed as within one of a number of chosen tolerances) of individual cigarettes, produced from the filler may be ascertained. In Specification 781,041 apparatus is described in which the mass of a cigarette rod 2, Fig. 1, is sensed by a radiation gauge 1 opposed to another gauge 3 sensing a nominal standard and the difference in their outputs, due to variations in rod mass, is used to control the speed of the tobacco hopper and to operate a recorder 10. The vibrating reed electrometer 8 used in this system gives a slowly changing signal adequate for tobacco feed control. For the analysis of the machine's performance based on a comparison of individual cigarettes, an electrometer 13 with a time constant within the range 15 to 50 milliseconds can be switched in at 11 so that rapid changes in mass of the rod can be followed by a stylus in a high-speed recorder 120 and by a contact arm 22 in a commutator switch for passing current to a total meter T and to one or other of five other meters according to whether the mass sensed is Extra Light; Light; Correct; Heavy; Extra Heavy. Meanwhile, the tobacco feed control is maintained by passing an appropriate signal back to the vibrating reed electrometer 8 through a plug 12. The high-speed system may be made portable to be plugged into each machine in turn for a few minutes or each machine may have its own high-speed electrometer connected electrically to contact points of selector switches at a central point where the machine to be analysed may be selected by setting a contact arm. The current meters 24 may be replaced by a fixed frequency oscillator feeding pulses to dekatron counters and, while an analysis may be started by throwing a manual switch, it may stop automatically at the end of a given count corresponding, say, to 2,000 cigarettes. The analysis may also be stopped automatically and the counters reset to zero if rod is not present or has ceased to move, which is sensed by the changed range of amplitude fluctuations of the signal. If an analysis shows a skew distribution and it is desired to study variations on the " heavy " side (say) in greater detail, the switches directing pulses to the " light " zones may be changed over to count in intermediate zones on the " heavy "  side. Means may be provided to check and adjust drift in the D.C. electrometer 13. The chart of the high-speed recorder may be marked with lines defining the zones by applying predetermined voltages through a calibrating unit. The pneumatic size gauge described in Specification 888,478 may be used upon the assumption that the mass is proportional to the size and when such a gauge is used a transducer converts its output into an electrical signal. A magnetic tape record may be made for say ten minutes, then formed into an endless band and played back at, say, a hundred times the speed of recording in order to facilitate the search for periodic abnormalities. Specifications 781,041, 888,041 and 929,338 are referred to.