| 摘要 |
PURPOSE:To maintain the distance between a nozzle and the work at a prescribed value up to the end part of the work, by providing a means for selecting sensors which puts plural pieces of sensors disposed near the circumference of the nozzle selectively in an operating state. CONSTITUTION:In the case of cutting a work 3 from the left end side, a right sensor 2d is connected to an amplifier 11 by a switching part 10 and a vertically movable motor 8 is run normally and reversely to control the height of a nozzle 1 and while the distance between the work 3 and the nozzle 1 is maintained at an optimum distance, the nozzle 1 is moved rightward and the work is cut. When the nozzle 1 approaches to the right end, the right sensor 2d tries to deviate from the work 3. Thereupon, a sensor selection signal 12 is emitted from an NC control device 9 to connect a left sensor 2c in place of the sensor 2d to the amplifier 11. Even if the nozzle 1 approaches to the right end of the work 3 and the sensor 2d deviates from the work 3, the height of the nozzle 1 is controlled by the left sensor 2c in accordance with the above-mentioned switching, whereby the cutting up to the end part of the work 3 is made possible. |
