| 摘要 |
PURPOSE:To assure the depth of fusion cutting by projecting plural pieces of laser beams at a specified width on both sides of the fusion cutting line of concrete to melt the concrete and to expel the molten concrete to the lateral and lower side of the fusion cut groove. CONSTITUTION:Three pieces of the laser beams 12a, 12b, 12c are projected within the specified width W on both sides of the fusion cutting line 16 of the concrete. The respective beams are disposed to deviate by a distance (t) each in the perpendicular direction at every distance (s) in the progressing direction and are partly superposed by each part; in addition, the beams are so projected that the melting circles of the 1st, 3rd beams 12a, 12c contact the outside end of the specified width including the fusion cutting line 16. The formation of the unmolten part of the concrete within the specified width W is prevented by the above-mentioned method and, therefore, the molten concrete is expelled laterally and downward without being clogged in the fusing cut groove 18. The depth of the fusion cutting corresponding to the beam energy is thus assured. |
