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 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.

Abstract: A web cutting control system controlling the speed of a rotary cutter for automatic, continuous and precise cutting of a web fed at a constant speed into predetermined lengths or on the marks on the web. Two transducers generate pulses the number of which corresponds to the web feed length and the rotating angle of the rotary cutter, respectively. Three sensors detect the marks on the web, the completion of cutting, and the arrival of the cutter blades, respectively, to control the flow of signals. A desired cutting length or the distance between the mark detection point and the point of completion of cutting is preset. A reversible counter receives the pulses from these two transducers and the difference signal between the preset value and a reference signal and performs reversible counting thereof, the result of which is used to control the speed of motor for the rotary cutter to bring its speed into synchronization with the web feed speed for accurate cutting.

Abstract: A web cutting control system controlling the speed of a rotary cutter for automatic, continuous and precise cutting of a web fed at a constant speed into predetermined lengths or on the marks on the web. Two transducers generate pulses the number of which corresponds to the web feed length and the rotating angle of the rotary cutter, respectively. Three sensors detect the marks on the web, the completion of cutting, and the arrival of the cutter blades, respectively, to control the flow of signals. A desired cutting length or the distance between the mark detection point and the point of completion of cutting is preset. A reversible counter receives the pulses from these two transducers and the difference signal between the preset value and a reference signal and performs reversible counting thereof, the result of which is used to control the speed of motor for the rotary cutter to bring its speed into synchronization with the web feed speed for accurate cutting.