| 摘要 |
1,222,905. Welding by pressure. CHICAGO MINIATURE LAMP WORKS. 25 Sept., 1969 [4 Oct., 1968], No. 47285/69. Heading B3R. [Also in Division H1] A method of securing a tungsten lamp filament 10 to a metal lead-in wire 12 comprises the following steps:- (1) Coating the end of the lead-in wire with gold; (2) Placing the filament across the coated end of the lead-in wire; (3) Placing a body 14 of gold on the filament and over the coated end of the lead-in wire; (4) Heating the body to a temperature below the melting point of gold but above the point at which diffusion of gold begins; and (5) Applying pressure to the body to cause the gold to surround the filament and form a diffusion bond with the coating on the lead-in wire. The body 14 is preferably formed as a ball 6-8 mils in diameter on the end of a 1À5 mil diameter wire 16, and the pressure is applied by a member 18 having a 2 mil diameter bore through which the wire passes. The lead-in wire 12 may be made of copper or dumet, and the temperature to which the body is heated may be in the range 600-650‹ C. |
