Machining condition setting device and 3D laser machining system

A machining condition setting device comprising:

• a move state simulation unit that simulates a move state of a machining head containing at least a relative position or a state of temporal change in a relative move speed of the machining head relative to a workpiece using 3D CAD data about the workpiece containing material information defining thermophysical properties including at least heat conductivity, specific heat, and density, and 3D CAD data about the machining head containing information at least about an outer shape of the machining head and about a relative position of the optical axis of a laser beam output from the machining head relative to the outer shape of the machining head, with an intersection point of a machining surface of the workpiece defined by the 3D CAD data about the workpiece and the optical axis of the machining head determined to be a machining point in virtual space, the simulation being conducted under a condition of moving the machining head relative to the workpiece along a machining line set as a path of the machining point determined when the machining head moves relative to the workpiece in the virtual space while the optical axis of the machining head is maintained at a predetermined angle from each of a normal vertical to the machining surface on which the machining point passes through and the machining line, and while a distance between an end surface of the machining head on a laser beam output side and the machining point is maintained at a predetermined distance;
• a thermal fluid simulation unit that conducts non-stationary thermal fluid simulation for obtaining a temperature distribution in a region covering at least a part of the workpiece to be changed by the move of the machining head outputting a laser beam;
• and
• a machining condition setting unit that sets a laser machining condition in advance containing at least a relative move condition for the machining head and a laser beam output condition before implementation of actual laser machining on the basis of simulation results obtained by the move state simulation unit and the thermal fluid simulation unit.