摘要 |
A cutting head for a laser-equipped machine tool in which the cutting head has a controllably positionable optic carrier for adjusting the position of the beam focus. The focusing optic has a reaction force imposed on it by the assist gas coupled to the cutting nozzle. The magnitude of the force varies with the pressure of the assist gas, and can be very substantial. A counterbalance mechanism connected between the cutting head and the optic carrier is operated from the same assist gas source which supplies the nozzle, and creates a force on the optic in the opposite direction of the reaction force and which has a magnitude which closely compensates it. The system also provides for rapid purge of assist gas when switching from one type of assist gas to another. |