| 摘要 |
PROBLEM TO BE SOLVED: To move the focus position to a proper position in a short time and to shorten the machining time by sensitively corresponding to the change of the shape or the machining condition of an object to be machined with the composition that the position of a condensing lens is changed by changing the hydraulic pressure inside a fluid flow-in part. SOLUTION: The position of a condensing lens 3 is regulated by changing the hydraulic pressure inside a fluid flow-in part 6 with a pressure regulator 10 based on the command of a controller 12. The hydraulic pressure inside the fluid flow-in part 6 acts toward to push up the condensing lens 3 to the other side of an optical axis, resisting the energizing force of an energizing means 7. The condensing lens 3 is ascended or descended from the standard position and the position is changed by changing the hydraulic pressure. Therefore, the focus position 13 of a laser beam 2 is changed. Because when the hydraulic pressure is changed, the condensing lens 3 is moved rapidly to the position of corresponding to the hydraulic pressure after changing, so the movement of the condensing lens 3 is executed in a remarkably short time, and the machining time can be shortened. |
