| 摘要 |
A dry-reed contact type of electrical switch is described. The dry-reed contacts have terminal elements constructed from a metal core having a copper covering. The terminal elements extend from the switch housing through fusible beads of printed glass in an airtight or gasproof manner. The material used for the metal core is selected to have an expansion coefficient corresponding to that of the fusible beads. The metal core is covered, first, by copper and then, by nickel in a quantity ratio equal to or slightly less than 1 part nickel to 5 parts copper. The terminal elements are exposed during the sealing process to a temperature of from 750 DEG to 980 DEG C. during a melting period of such duration that at least 85 percent of the quantity of nickel coating is diffused into the copper. |
