GB731113A - Improvements in and relating to paper tubes enclosing plug elements - Google Patents

Abstract

731,113. Automatic alignment control systems. BUNZL, H., SCHECHNER, P., and CIGARETTE COMPONENTS, Ltd. April 28, 1954 [March 24, 1953], No. 8134/53. Class 38 (4). [Also in Group VI] To compensate for stretch in superposed webs 10, Fig. 2, wrapped in a garniture 14 round spaced filter plugs delivered on to the webs by means 28 (see Group VI), the resulting continuous rod being cut centrally of the plugs and spaces therebetween by a rotary knife 38 to form cigarette filter tips, the rate of delivery of the plugs to the webs is varied relative to the instant of cut of the knife by adjustment via a servo mechanism 49 of the speed ratio of a gear 41 driving the means 28. Photo-electric cells 59, 62 actuated by light respectively passing through the interplug spaces and a slit in a disc 60 on the knife driving shaft 42 produce signals fed through respective amplifiers 64, 65, Fig. 7, to an adding circuit 66 whose output is fed to a relay 67 including switches 68, 69 operated alternatively to supply control voltages to the servo mechanism 49. The signal from the cell 59 is arranged to give the basic wave form A shown in Fig. 8c, and, when the knife 38 is cutting centrally of the plugs and spaces therebetween, the pulse signal from the cell 62 is positioned at Y relatively thereto and adds to this wave-form to give a voltage Y<SP>1</SP> to which the relay 67 is not responsive. Relative movement of the signal from the cell 62 to a position X or Z gives a voltage X<SP>1</SP> or Z<SP>1</SP> to which the relay 67 responds to close a respective switch 68 or 69 and restore the signal to the position Y. The circuit is supplied with power from a source 70 via a time-sharing circuit 71 arranged to permit and prevent operation of the servo mechanism 49 in some predetermined sequence, and which may be a thermally-operated relay or a switch actuated by a cam driven by a synchronous motor or by some continuously rotating member of the apparatus.