Abstract: A web butt-joining system having a feeding section with rolls for feeding a pair of new and old webs, a cutting and joining section having cutting drums and joining drums, and a drive control section. The latter is composed of a driving DC motor commonly coupled to the cutting drums and joining drums. A calculation control circuit drives the DC motor and drive control section is operated to cut said new and old webs fed from said feeding section and piled one on another with said cutting drums and to butt-join the ends of said webs thus cut with bonding tapes provided on said joining drums.

Abstract: A method and apparatus for cutting a web into a specified length in which an upper cutting edge and a lower cutting edge are provided respectively above and below the web run at a constant speed. The web is cut into the specified length by moving said upper cutting edge vertically while said upper and lower cutting edges are swung in the web movement direction. The swinging and vertical movements of said cutting edges are accomplished by rotation of an eccentric crank shaft driven by a DC motor. A rotation angle of the eccentric crank shaft and a movement length of said web are outputs provided in the form of pulses, respectively, in order to coincide a movement speed of the web with a swinging speed of the cutting edges in cutting said web.

Abstract: A method for controlling the speed of a rotary cutter to cut a continuously ed web accurately into predetermined lengths. A desired cutting length and the circumference of the rotary cutter are preset. The web speed as detected is multiplied by a coefficient equal to the cutter circumference divided by the cutting length. The resultant signal is compared with the cutter speed as detected, and, if there is any difference, the cutter speed is corrected for accurate cutting.