| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To enable supplied powder metal to sufficiently absorb the energy of a laser beam in a welding using the laser beam. <P>SOLUTION: The laser beam 21 is reflected on a conical outer surface mirror 2, reflected on a conical inner surface mirror 3 and becomes an annular beam 22. The beam 22 is reflected on a flat mirror 1 and on a flat mirror 4, passes through a window 5, and is deformed into an annular beam 23 in which the diameter of the hollow part having no light intensity distribution decreases with a prism 6 according as the beam progresses. A valve face of an engine valve 10 is irradiated with the beam at a point at which the annular beam 23 becomes a solid beam 24. Further, the powder metal is supplied from the end of a pipe 8 into the beam at a region in which the annular beam 23 is changing into the solid beam 24. Thus, the supplied powder metal absorbs the sufficient energy of the laser beam. A build-up welding is performed in this way. <P>COPYRIGHT: (C)2003,JPO</p> |
