| 摘要 |
PURPOSE:To remove the voids in solder and to prevent the oxidation of a heater, etc., by evacuating the inside of a vacuum vessel or generating a state of sealing an inert gas therein while solder is held molten. CONSTITUTION:The optical fiber feed through is set at the time t0 and the vacuum vessel is evacuated by operating a vacuum pump to put the vacuum vessel into the vacuum state. The heating of a heater built in the vacuum vessel is then started from the time t1. The solder in the optical fiber feed through is, therefore, heated gradually and the molten state is attained at the time t2. The operation of the vacuum pump is then stopped at the time t3 and the inert gas is sealed into the vacuum vessel by opening a solenoid valve. The solder of the molten state is then subjected to the pressure rapidly from the circumference and is welded completely to the corners at the point when the sealing is executed by solder. The voids are rapidly removed from the inside of the solder by pressurization. In addition, the voids are removed and the oxidation of a heater, etc., is prevented. |
