The concept of tool point, cutter location and tool change point are briefly described.
Tool point refers to the cutter point at the beginning of the program; the tool change point is the relative position of the tool when the tool needs to be changed during machining.The knife point can be set in parts, machine tool fixture or above, design or process as much as possible in the benchmark reference parts; change point are often located in the workpiece outside, to smoothly change the knife, not the workpiece and other components for collision.
After the machine tool is determined, the workpiece coordinate system is determined by determining the origin of the workpiece, and each movement axis code in the processing program controls the relative displacement of the cutter. For example, when a program starts, the first program segment is "N0010 G90 G00 X100 Z20", which means that the tool moves rapidly to the workpiece coordinates at X=100mm Z=20mm. Where did the cutter begin to move to the above position? So at the beginning of program execution, must determine the tool movement in the workpiece coordinate system to start position, this position is a program execution tool relative to the workpiece so that the starting point, the starting point or starting point of cutting process. This starting point is usually determined by the tool setting, so the point is also called the tool point.
The commonly used tool site provisions: mills, cutter of end milling cutter axis and the bottom surface is the tool point; ball end milling cutter location as the center of the sphere; the tool tip site for boring, or the arc center; drill or drill bit is the center of the bottom surface; cutting tool is axis and parts the intersection of line electrode.
