| 摘要 |
PURPOSE: To provide an underwater lamp structure preventing the fracture of a tubular bulb and keeping the bulb hardly exposed. CONSTITUTION: Regarding an underwater lamp with a projected bend section 2 formed around the base end of a tubular bulb 1, the radius C of the bulb 1 at a position nearer a base 3 than the section 2 is made smaller than the radius A at a position nearer a forward end than the section 2. More specifically, when the radius of the section 2 is denoted by B, the radii are so formed as to satisfy the following inequalities: B>A+0.5mm, and A>C+0.5mm. According to this construction, the pressing force of an elastic packing to press the section 2 becomes larger at the forward end than at the base 3 of the tube 1. As a result, a force acts to push the tube 1 toward the base 3 and watertightness is enhanced, thereby preventing the occurrence of water leakage or the like. |
