| 摘要 |
PURPOSE:To enhance the manufacture efficiency of a tubular bulb by placing two sets of center valves one upon another on the same axis, and by constituting a simple valve device having the equivalent function of a sealing center valve and an exhaustion center valve. CONSTITUTION:In performing the sealing process of a tubular bulb, a fuel gas supply route 11 is opened through the rotation of a movable center valve 10, and a sealing burner is lit so as to fuse the peripheral part of a stem mounted to the opening end of a straight bulb. After the sealing process is completed, the route 11 is closed through the rotation of the valve 10. Through the rotation of a movable center valve 3, which accompanies the rotation of the valve 10, an exhaust route 4, a charging route 5 and a washing route 6 are opened so as to carry out gas exhaustion, washing and charging of argon gas. Following that, the routes 4, 5 and 6 are closed through the rotation of the valve 3, and sealing- off of the bulb is carried out with a sealing-off burner. |
