| 摘要 |
PURPOSE:To prevent glass tubes from being damaged due to heating in the production process by providing a metal terminal plate to be fixed to a previously formed glass tube receiving part by means of glass frit, with the stress absorbing part concentric with the glass tube receiving part and having a U-shaped or inverted U-shaped section. CONSTITUTION:An outer tube bulb 1 has an almost circular open end 2 and the open end 2 is a metal terminal plate 3 and airtightly fixed with frit 9. Inner tubes 51 and 52 made of glass contain air-tightly electrodes 41 and 42 buried into the terminal plate 3, while their other terminals are open and their inner faces are covered with phosphor layers 61 and 62. A ring-shaped U-groove glass tube receiving part 7 is formed on the peripheral part of the terminal plate 3 corresponding to the open part 2 and a stress absorbing part 8, which projects concentrically into the bulb 1 continuing from the inside of the receiving part 7, and has a section bending in the U-or-reverse U-shape, is provided. The thickness of the terminal plate 3 is to be 0.2-0.6mm., while the height from the frit upper surface on the top part of the absorbing part 8 is to be H1, the height from a base level of the terminal plate is to be H2 and the diameter D of the circle drawn by the top part of the absorbing part 8 is set up by the formula: (H1+ H2)/D>=1/15 thus being able to prevent the glass tubes from being damaged due to heating at the time of manufacture. |
