| 摘要 |
PURPOSE: To certainly prevent ultraviolet emission when a cover is broken, by providing a mechanism for breaking an electric current in a ballast means when an open state of a conductive strip occurs. CONSTITUTION: In this luminaire, a glass break detection circuit 50 is provided in a ballast circuit 40. The detection circuit 50 includes a cover member 26 and a conductive strip 42. When the conductive strip 42 is broken due to a break of the cover member 26, the glass break detection circuit 50 loses electrical continuity, so that energization to a relay coil 58 is cut off to open a contact member 56. In the case where a current successively flows through an input part 44 of the ballast circuit 40 with the contact member 56 opened, the steady- state current in the input part 44 is large enough to melt down a fuse member 54. Because the fuse member 54 cuts off the current after the opening of the contact member 56, it is not necessary for the contact member 56 to cut off the current. The cutoff of the current in the input part 44 cuts off a current flowing through an auto-regulation transformer 46 to stop operation of a light source 30. |
