GB1375344A - - Google Patents

Abstract

1375344 Cutting sheet materials WESTVACO CORP 16 Jan 1973 2249/73 Heading B4B Sheet cutting apparatus includes a sheet length adjustment and control arrangement comprising a pair of cone pulleys 38, 40, the pulleys being joined respectively to a feed roll 46 and cutter roll 19 and connected to each other by timing belts 43, 13, 39, the cone pulley connecting belt 39 being shiftable to adjust the timing between the feed and cutter rolls. The shift is produced by means responsive to signals from both of them to maintain sheet length between prescribed limits. A readily interchangeable timing pulley 49 permits changes of sheet length over wide limits. Adjustment of the belt 39 is achieved by rotation of a shaft 36 by a motor 34 to shift a belt guide 37 in response to signals 60 or 61 from a digital counter 25. The counter is set to the upper and lower limits which are shown at 27, 29 and the actual length being cut is shown at 28. Speed indicative signals 23, 31 and 47 are fed into the counter from the main drive motor 10, the cutter roll 19 and feed roll 46 respectively and signals which result in readings on 28 which fall outside the limits set on 27, 29, cause emission of a signal 60 or 61 to cause movement of the belt guide 37 in the appropriate direction. A warning light indicates out of limit conditions to the operator. The machine is arranged to be operated manually insofar that by pressing an appropriate button, the operator may cause the belt shifter to move the belt 39, and the machine changes from automatic to manual control after a predetermined time. The drive motor 10 feeds in a signal 31 from a tachometer 8 to ensure that the belt 39 will not be shifted until a practicable pulley speed is reached.