| 摘要 |
PURPOSE:To prevent the generation of the whiskery burr in the circumference, by expanding the sheet blank provided with the frill at its unperforated part. CONSTITUTION:The perforations 1 to be expanded later are installed in the sheet blank of the expanded metal, and the frills 2, 3, are formed in the circumfernece. Besides, the frills 4 are formed in the surface of the sheet blank so as to linearly line up in the direction of the expanding work. These frills 4 are provided in plural lines according to the necessity. Next, this sheet blank is expanded for expanding and developing the perforated parts 1, and at the same time, the frills 2, 3, 4, of the unperforated part are flatly expanded. Accordingly, by shearing not only the circumference as the electricity collecting body but also the inside of the sheet surface along the line A-B, the burrless strip type expanded metal can be obtained. The shape of frills 2, 3, 4, can be variously selected correspondingly to the need. |
