| 摘要 |
<p>A sheet of semi-rigid plastics with a thickness of 0.4mm is bent to a V-shape and welded to the support bars (4, 5). The support bars are formed from metal strips coated with plastics to facilitate the welding on of the file body. The welding is carried out either by hot pressing or by ultrasonic means. This method of manufacture is applicable to files suspended from one end with the long dimension vertical. In this case the body of the file is welded to plastics coated wires which have hooks formed at one end.</p> |
