| 摘要 |
1,228,286. Manufacture of printed circuit boards. GRAPHIC ELECTRONICS Inc. 18 Nov., 1969 [9 Jan., 1969], No. 56464/69. Heading H1R. A printed circuit board is produced directly from an original copy on an engraving machine of the type in which the copy, mounted on a first cylinder, is scanned photoelectrically to control a V-shaped stylus which removes a conductive metal surface from a thin laminate wrapped round a second synchronously driven cylinder. An additional layer of backing material may be secured with adhesive to the back of a completed circuit board to increase its thickness and rigidity. A coating of solder may be applied, e.g. by electroplating, to the surface of the conductive metal layer prior to the cutting operation to facilitate the subsequent soldering of components thereto. The cutting stylus is manufactured from tungsten carbide. The engraving machine has a reversing switch to control the cutter head so that printed circuit boards may be made either from positive or negative original copies. |
