| 摘要 |
PURPOSE: To form an electric bulb shaped fluorescent lamp of dustproof and splashproof construction by installing a roof on a part of the vicinity of a base part of a ballast unit to seal up the inlet of a clearance between the ballast unit and an arc tube when the arc tube is mounted. CONSTITUTION: An arc tube 5 is mounted and fixed so as to cover the surroundings of a ballast unit 4 integrating a base 1, a cutout 2, a starting device, etc., and covered with an outer case 3. In addition, a roof 6 for dustproof and the splashproof is installed on a part of the upper top part of the unit 4. As the roof 6 is installed, a clearance 7 between the fitting parts becomes a closely contact and sealed up structure to be intercepted from the outside by the top part of the arc tube 5 and the roof 6 when the arc tube 5 is fitted. Thereby, dust and rain is prevented from entering the clearance 7, so that a safe and easily maintained lamp can be formed. |
