LASER BEAM MACHINE

PURPOSE:To enable the stable laser beam machining having constant optical path by forming the optical path between a laser oscillator and machining head with a rotary optical guide, which executes rotary motion in the whole, while the end part of at machining side and end part at opposite side respective ly execute linear motion in X, Y directions. CONSTITUTION:A machining head 300 performs linear motion in Y axis direction as restrained to the guide face of a column 150. Along with this motion, rotary devices 530, 570 at both ends of the rotary guide 550 perform rotary motion, further, while the first rotary device 530 performs linear motion in X axis direction along with an extending/retracting device 600, the rotary guide 550 performs smooth rotary motion. At this time, a laser optical path length between an oscillator 200 and machining head is changed by a length of extending/ retracting of an extending/retracting member 615, this changing amount is extremely small as compared to the whole optical path, there is no influence on machining condition. Also, the rotary guide 550 is of integrated, having no backlash, so as to have high rigidity in light weight, accordingly, in the high speed machining accompanied with rapid acceleration/deceleration, influence of vibration is avoided.