For the machine tool installed with the tool setter, the actual coordinate value of each direction from the tool setter sensor to the zero points of the machine tool coordinate system is a fixed value. It needs to be accurately determined by the parameter setting method to satisfy the use, otherwise, the numerical control system will not be able to convert the mutual position data between the machine coordinate system and the fixed coordinate of the tool setter.
When the machine tool has established "machine coordinate system" and "fixed coordinate of tool setter" (different specifications of the tool setter should be set with different fixed coordinate values), the working principles of the tool setter are as follows:
1. After each linear motion axis of the machine tool returns to its mechanical reference point, the relative positional relationship between the machine coordinate system and the fixed coordinate of the tool setter establishes a specific value.
2. Whether the lathe tool setter is operated by automatic programming control or manual control, when the moving tool moves along a selected axis, the tooltip (or the outer diameter of the power rotary tool) is leaned against and touches the corresponding plane of the probe on the four sides of the tool setter, and after the high-precision switch sensor is triggered by the swing of the flexible support rod, the switch will immediately inform the system to lock the movement of the feed shaft. Because the numerical control system treats this signal as an advanced signal, the control of the action will be extremely fast and accurate.
3. Since the linear feed shaft of the CNC machine tool is equipped with a pulse encoder for position loop feedback, there is also a counter in the CNC system that remembers the actual position of the feed shaft. At this time, the system can determine the initial tool offset value of the tool tip (or diameter) of the shaft tool by reading the accurate position of the shaft stop and automatically converting the relative relationship between the machine tool and the tool setter. In other words, if put it in the machine coordinate system to measure, it is equivalent to determine the distance between the machine tool reference point and the zero point of the machine tool coordinate system, the distance between the tool measuring point and the zero point of the machine tool coordinate system and the actual deviation between the two values.
4. No matter the tool wear caused by the cutting of the workpiece or the tool tip variation caused by the thermal elongation of the screw, as long as the tool alignment operation is carried out again, the CNC system will automatically compare the measured new tool offset value with the initial tool offset value, and automatically add the error value that needs to be compensated into the tool compensation storage area. Of course, if a new tool is replaced, and then the tool is realigned, the obtained offset value should be the new initial offset value of the tool.