| 摘要 |
PURPOSE:To make a lamp voltage correctable to let it be in a specified range without breaking an outer tube by forming a member for control with a metal of a lower melting point than those of other metallic members inside the outer tube in order to make it easily melt by energizing it. CONSTITUTION:As for a lamp which has a lower lamp voltage than a specified range, a voltage is applied between lead wires 9a and 9c of an outer tube by an external source; then a current flows through a circuit consisting of: the outer tube lead wire 9A - a luminous tube supporter 8A - a holder 7A - a metallic exhaust tube 6 - A a control member 10 - the outer tube lead wire 9C. The control member 10 made of a metal of the lowest melting point is easily heated and melted. If the control member 10 is melted, the heat loss through the member 10 is removed, which raises the temperature of the coldest part, and the vapor pressure of sodium amalgam is raised to shift the lamp voltage to a higher region. The lamp voltage can be thus shifted into a specified region. Thereby a lamp can be renewed without breaking the outer tube.
|
