CNC machine tool screw gap
For a pure driving situation, general requirements for flexible transmission, allow a certain return to the gap (small, usually a few silk), using a single nut, it is cheaper and more flexible transmission; for a return to the precision of gear clearance conditions is not allowed, it is required to choose double nuts, it can adjust the magnitude of pre tightening force, keep good, and can be repeatedly adjusted; in addition, restricted travel in space, also can choose the variable lead preload (commonly known as stagger preload), the pretightening force is small, and it is difficult to repeat adjustment, generally do not choose.If the gap is large, please timely maintenance, system compensation value can not be too large, in the case of large gap screw, continue to use, will greatly shorten the service life of the lead screw, and easy to cause damage can not be repaired
Clearance will have an effect on accuracy, as reflected in reverse machining.If the tool has been along the -z direction, and then suddenly reverse to the +z direction, the reverse screw gap, the tool will stagnate for a little, and the reverse gap after the elimination of cutter movement, but then the coordinate CNC machine has change a value, that is to say with the actual tool position has been produced the deviation of coordinates.If there is still a larger size deviation of the repeated tool, then there may be a parameter problem or a reverse gap is too large.Numerical control machine tool is the abbreviation of digital control tools numerical (Computer control machine machine), it is a kind of automatic machine tool with program control system. The control system can logically process programs that have control, coding, or other symbolic instructions, decode them, encode them in numbers, and input them through an information carrier. After operation, various control signals are sent out by the numerical control device, the movement of the machine is controlled, and the parts are automatically machined according to the shapes and sizes required by the drawing. CNC machine tools to solve the problem of complex and precision parts processing, small batch and multi variety, is an effective and flexible, automated machine tools, represents the development trend of control technique of modern machine tools, is a kind of typical mechatronic products.
