| 摘要 |
PURPOSE:To catch metallic vapor by a shielding plate and prepare for welding during ventilation time and improve working efficiency by providing a shielding plate having a beam passing hole and an observation hole in the upper part of a rotary table on which a work is mounted, and positioning an electron beam irradiating axis and the beam passing hole on a straight line. CONSTITUTION:Position of irradiation of an electron beam Y is confirmed using a telescope 6. At this time, the lock arm of a shaft 12 for moving a shielding plate is removed and an observation hole 20 on the shielding plate is moved to just under the electron beam Y. When a sliding plate 7 is adjusted by a screw 27 to align the electron beam axis to the weld line and fixed by a lock arm 10, a limit switch 18 gives a signal of welding OK. These operations are performed until specified degree of vacuum is attained. Then, an electron beam is irradiated. The electron beam Y is irradiated through a beam passing hole 19, 1.3- 1.5 times the flux of electron beam, provided on the shielding plate. |
