METHOD AND DEVICE FOR SELECTIVELY FORMING DECORATING ONTO HOLLOW ARTICLE HAVING AXIAL SYMMETRY BY LASER BEAM

摘要

PURPOSE: To selectively form a decoration on a hollow article by causing a laser beam of specific wavelength to act upon the length of the hollow article from the inner layer to the outer layer so that the laser beam coincides with the symmetrical axis of the hollow article. CONSTITUTION: A decoration is formed on an axially symmetrical hollow article with a laser beam. The axially symmetrical article 2 to which the decoration is to be imparted, is formed of a two-tier material and is set upright by a support 7 on a fixed base and does not rotate around the symmetrical axis during a step to impart the decoration. The laser beam 1 with a wavelength of 0.5-2.0 μm is applied with a maximum tolerance of ±10 mm in such a manner that the laser beam coincides with the symmetrical axis. The laser beam is focused by a lens 5 and is maintained, in a freely sliding manner, in the symmetrical shaft 3 direction of the hollow article 2. The optical axis 4 of the lens 5 coincides with the symmetrical axis 3 within the tolerance of ±10 mm. A reflector 6 is arrange on the symmetrical axis 3 of the hollow article 2 in such a manner that the reflector 6 is slidable and rotatable. A drive device makes positive the motion of the lens 5 and the reflector 6 in the symmetrical axis 3 direction of the hollow article 2 and the motion of the lens 5 to the reflector 6. Thus it is possible to keep the focal point of the lens 5 constantly on the outer surface of the hollow article 2.