| 摘要 |
781,557. Making contact-springs. WESTERN ELECTRIC CO., Inc. Feb. 22, 1956 [Feb. 24, 1955], No. 5496/56. Class 83 (2). [Also in Groups XXXVII and XXXIX] In a method of making an electric switch contact wiper spring, a strip 10 of suitable metal such as nickel silver is punched to form indexing holes 12 and then to form notches 13 to leave tips 14. To one face of each tip a rectangular plate 16 of precious metal such as an alloy of gold, silver and palladium is welded and trimmed to form rounded side-portions 18 after which the composite tip is curved to convex form, Fig. 5. Further punching operations are carried out to form holes 29, arcuate slots 30, embossings 31 and bends 26, 27 and 28 and finally the whole wiper is severed from the strip. |
