| 摘要 |
PURPOSE:To increase the strength of a tubelar bulb and its durability by making an inserting through-hole directly in a mount tip, which is made of a heat-resistant insulating substance as a united body, and also on its base end portion, forming an exposed pit extended to the inserting through-hole. CONSTITUTION:A mount 2 is held by inserting through an exhaust pipe 10 of the mount 2 in a tipping burner mechanism 9, connecting its head portion with an exhaust enclosing mechanism and setting a circular inner surface of a flared portion 4 in a front end portion of a mount tip 1. In the next, the mount 2 is inserted in a bulb 5, and a circular edge portion of the flared portion 4 is made to fit on an opening edge of the bulbe 5. Then, the mount 2 is fixed and sealed by a sealing burner 6, and after an electron-emitting substance is activated by lighting a filament 16, the bulb is evacuated and charged with a gas, and the exhaust pipe 10 is sealed and cut. Thus, the strength of the tubelar bulb and its durability are increased by making the mount tip of ceramics or the like as a united body. |
