The machining accuracy of CNC machine tools ultimately depends on the accuracy of the machine tools themselves to ensure the accuracy of CNC machine tools, including geometric accuracy, positioning accuracy, repeatable positioning accuracy, and cutting accuracy.
Geometric precision: also known as static precision, is a comprehensive reflection of the key parts of the CNC machine tool after the assembly of the comprehensive geometric shape error.
Positioning accuracy: indicates the accuracy of the motion of the measuring machine under the control of the numerical control device. According to the measured positioning accuracy value, the best machining accuracy can be judged in the automatic machining process of the machine tool. It refers to the difference between the actual position of parts or tools and the standard position (theoretical position, ideal position). The smaller the difference, the higher the accuracy. It is the premise that machining precision of parts can be guaranteed.
Repeated positioning accuracy: refers to the consistency of position accuracy obtained by repeatedly running the same program code on a CNC machine tool. It is the consistency of continuous results obtained by processing a batch of parts under the same conditions (for example, on the same CNC machine tool, if the same part program is applied, but the operation method is different, the results will be consistent).
Cutting accuracy: it is a comprehensive check of the geometric accuracy and positioning accuracy of the machine tool under the condition of cutting.
It can be seen from the above, CNC machine tool precision of high and low mechanical and electrical aspects, mechanical aspects such as spindle precision, such as jumping, bus, etc.. Precision of lead screw. The precision of the fixture, the rigidity of the machine tool, and so on. In the electrical field, the control mode is mainly semi-closed loop, full closed-loop, feedback and compensation mode, interpolation accuracy during machining, etc. So the accuracy of the machine does not depend on whether the machine is a fully closed loop.