| 摘要 |
<p>A severing blade comprising a plurality of spaced-apart extended members, each of said extended members having a blunt upper edge extremity and at least one side-extended tooth with a piercing tip disposed below the blunt upper edge extremity and in the plane of the blade so that a stretchable film transversely pulled over the severing edge will be snagged on the side-projected teeth thereby causing a segment of the film to be severed.</p> |
