Patent GB-865529-A (GB)
Title: Cutting
IPC: B26D3/16
Filed: 1957-12-31
Abstract: 865,529. Cutting rolls transversely. CELANESE CORPORATION OF AMERICA. Dec. 31, 1957 [Jan. 23, 1957], No. 40417/57. Class 31 (1). [Also in Group XXII] A device for longitudinally cutting sheet material in roll form to form two or more narrower rolls comprises means for carrying and axially rotating the roll of sheet material, cutting members adapted to make at least one pair of parallel cuts in the roll from the outside inwardly and at right angles to the axis of the roll, and means for simultaneously unwinding the strip of material between the parallel cuts. As shown in Figs. 1 and 4, a roll of plastic film 11 is cut by means of a pair of knife blades 19 disposed at the free end of a pivotally mounted lever arm 21 provided with an adjustably mounted weight 23 for urging the knife blades into contact with the film material on the roll 11. As the roll of film is rotated, the edges 24 of the knife blades cut continuously into the film so that a strip 29 is cut from the main body of film material on the roll. The cut strip 29 is withdrawn continuously by a suction disc 31 and travels through a U- shaped guide 38 which twists the cut strip at an angle to its original position on the roll 11. Unwinding of the main body of film material on the roll 11 is prevented by means of a strip of adhesive tape 33, Fig. 1. The depth of cut is controlled by means of a rider plate 26 which is disposed between the cutting edges 24 and presses against the bottom of the groove 32 in the roll. A stream of cool air is directed into the groove 32 from the outlet 34 of a bent tube 36 mounted on the lever arm 21 and connected to a source of air by a flexible hose 37. In a modification, Figs. 6 and 7 (not shown), the rider plate is replaced by a series of freely rotatable rollers arranged in a line along the length of the knife blades 19. In another modification, Figs. 9 and 12, the knife blades 66, which are of disc type, are disposed at the free end of a pivotally mounted lever arm 68 and are urged into contact with the film material on the roll 11 by a pneumatic cylinder 67. A rider wheel 76 is disposed between the cutting edges 84 of the knife blades and is provided with integral vanes for moving air from one side to the other thereof, the flow of air being facilitated by means of holes 92 in side plates 71. The cut strip 29 is removed by means of a stripping wheel 93 freely rotatable on an axle 96 of a pivotally mounted arm 97 and pressed against the bottom of the groove 32 by means of a pinch roll 99 freely rotatable on an axle 101 at the end of a pivotally mounted bell-crank lever 102 provided with an adjustably mounted weight 103. The cut strip passes on to a rubber surface 94 of the wheel 93, between the wheel 93 and roll 99 and then to a suction device 106. To prevent the cut strip from wrapping round the wheel 93 and the roll 99, these members are provided with circumferential grooves in which the ends of spring fingers 109, 111 are received. In a further modification, Fig. 14 (not shown), the pinch roll is replaced by a freely rotatable hub adapted to support a core on which the cut strip is wound as it is removed.