A device for the adhesive bonding of a running web at a circumferential web on a spare roll.

摘要

977,565. Feeding webs. CROSFIELD ELECTRONICS Ltd. Feb. 7, 1963 [Feb. 13, 1962], No. 5495/62. Heading B6B. [Also in Division G1] A printed web 3 from an expiring roll 4 is spliced to a printed web on a replacement roll 2 by a brush 9, the operation of which is controlled to preserve correct registration of the printed patterns of the webs. A strip of magnetic foil is secured by adhesive to the periphery of the roll 2 at a determined position in relation to the printed pattern thereon. The strip 15 is detected by an electromagnetic sensing device 16 connected to a pulse generator 17, while a photo-electric detector 12 senses register marks 10 on the expiring web 3. The detector 12 is connected to a pulse generator 14. Both pulse generators are connected to a register detector 13. When signals from the sensing device 16 and detector 12 are in coincidence the detector 13 initiates splicing, such that the brush 9 is actuated to press the web 3 against roll 4, thereby causing an adhesive area 5 to stick to the web 3 and a securing tab 6 to be torn. A knife (not shown) is also actuated by a signal from the detector 13 to cut the expiring web 3 after splicing. The device 16, Fig. 2, comprises a soft iron core 20 energized by a winding 21, thus generating a magnetic field 23. Passage of the strip 15 produces a small electromotive force of waveform 26 in a coil 25 by producing a disturbance in the field 23. The signal is fed to a linear amplifier 29 and a trigger circuit 30 which produces an output pulse of short duration. The strip 15 of magnetic foil may be replaced by a strip of magnetic ink or tape. Specifications 797,527 and 914,150 are referred to.