| 摘要 |
PURPOSE:To reduce the piercing time for a work made of thick plate CONSTITUTION:The melting light L2 generated at a piercing part 5a is received by a detecting means 9 during the piercing operation to a work 5, and inputted into a control device 4. The control device 4 is provided with a focal point correcting part 4A, and this focal point correcting part 4A increases the output of the laser beam L to the value where the detected quantity of light of the melting light L2 becomes larger than the prescribed reference value every time the detected quantity of light of the melting light L2 becomes larger than the prescribed reference value. This constitution increases the output of the laser beam gradually as the piercing is advanced, and allows the efficient piercing. Thus, the time required for the piercing can be reduced compared with the conventional value even with the work 5 of thick plate. |
