| 摘要 |
PURPOSE:To enable a forward confirmation distance to be sufficiently taken, and protect an opposite vehicle or the like from being dazzled, while maintaining a suitable forward confirmation distance at the time of extinction, by applying specific values to a distance between the main filament and sub-filament of a sealed beam bulb made to the predetermined standard, and the wattage thereof. CONSTITUTION:In the sealed beam bulb defined by JIS E4404, a power supply of 100V is provided and a distance between a main lighting filament 11 and sub-lighting filament 13 laid at the center of the bulb is taken between 6mm and 8mm. In addition, the filament 11 is rated at 250W and the filament 13 at 100W. According to the aforesaid construction, it is possible to obtain a sealed beam for the front signal lamp of a railway vehicle enabling a forward confirmation distance to be sufficiently taken, and an opposite vehicle, people on a platform or the like to be protected from being dazzled, while maintaining a suitable forward confirmation distance at the time of extinction. |
