| 摘要 |
PURPOSE:To prevent perforation from being generated and improve workability and reliability by covering the circumference of a section where an exhaust tube is chipped off with a glass tube and chipping off the exhaust tube together with this glass tube. CONSTITUTION:When the exhaust tube for an electron tube, such as a cathode-ray tube, etc. is chipped off, a glass tube 14 is fit only to the circumference of a section 13 which is heated while an exhaust tube 12 formed on a glass stem 11 is being chipped off. When the exhaust tube 12 is heated and chipped off together with the glass tube 14, no suction is generated due to insufficiency of glass since the glass of the section 13 which is heated is thick. Thus even an exhaust tube with a thin glass can be prevented from being perforated. As a result, workability and reliability can be improved. |
