| 摘要 |
A cutting device having blades with V-shaped cutting edges and shaped to cause the blade centers to deviate from a vertical plane. One blade is reciprocated. The outer ends of each blade have sliding projections engaging marginal portions of outer surfaces of the other blade so that the cutting edges are drawn toward and cross-over one another during cutting, whereby the blades increasingly move from their bent shape toward a planar shape. The blade edges cut a web from both outer edges toward the center, the center portion of the web being cut last. The blades resume their V-shaped configuration when moved to the open position. By limiting the stroke of the moving blade, the center portion of the web being cut remains uncut. The blades have support frames holding one end of the blades fixed while the opposite ends of the blades are permitted to slide to accommodate movement of one end of the blades which are elongated as they flatten. The cutting edges of the blades may be modified to make a complete cut, a partially perforated and partial cut and a perforated cut, across the web. The blades may be driven by a variety of driving devices such as solenoids, motor driven cams and permanent magnets.
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