Efforts to improve the numerical control lathe position precision and accuracy stable
Efforts to improve the numerical control lathe position precision and accuracy stable release date: 2016 - 08 - 01 clicks: a 2012 times, efforts to improve the position accuracy of nc lathe in the servo system design should be paid attention to during the process of moment of inertia and torque match, increase the mechanical inertia, the rigidity and reduce the system to reduce the response time of the mechanical transmission parts. Load inertia JL by the board and the head installed above the ball screw, coupling, such as linear and moment of inertia of rotating parts or to the servo motor axis of inertia, JL changes according to the cutting load change. JM for servo motor rotor moment of inertia. According to the characteristics of the servo motor, control the ratio of JM and JL. In the ball screw assembly process should pay attention to the following: after bearing fixed on both ends of the screw, ensure the screw on the busbar and busbar side respectively with CNC lathe principal plane of the rails and parallel to the plane; To ensure that the screw nut axis and screw axis coincidence ( Grinding adjustment gasket) ; To ensure that the screw nut installed end face and the screw axis vertical. Screw is a slender, bar parallel to screw deflection of the deviation, directly affect the positioning accuracy. Screw nut and the screw nut installed face is not vertical could lead to nut uneven, screw friction heat is serious, cause screw heat distortion, will affect the repeat positioning accuracy. In order to ensure the screw have good rigidity and dynamic characteristics, screw assembly must be done when the pre-tension, to compensate for temperature of the thermal deformation. At the same time to control the lock nut at the ends of the screw locking torque and servo motor and ball screw connection stiffness, otherwise you will have an effect on the transmission precision of machine tools. Should improve the quality and performance of CNC lathe guideway cover, steel shield shell itself, of which the one layer or layers of armor plate is moving with dragging plate, shield shell needs to be easy, smooth running, there can be no interference phenomenon, otherwise will affect the positioning accuracy of machine tools. Second, the measures to improve nc lathe accuracy stable common CNC lathe bed base, spindle box, such large cross dragging plate structure, in the production process of casting, heat treatment, machining of residual internal stress in part, with parts of internal stress is always in a state of instability. To eliminate parts of structure deformation caused by the internal stress and geometric accuracy change, should choose appropriate aging method to eliminate internal stress, such as natural aging, thermal aging and vibration aging; Second, reasonable arrangement of process technology, including the rough, finishing the order and the distribution of the machining allowance, limitation of times and time, as far as possible to eliminate the residual stress inside the parts before finishing. In the process of nc lathe assembly, on the head and dragging plate, the base of the spindle box and fixation combined with surface, the ball screw nut and bearing seat with fixation combined with surface must adjust their research and dye penetrant inspection, to ensure that components in combination with the contact stiffness, which is one of the measures to improve the machine tool accuracy stable. Calorific value is big, numerical control lathe cutting process to control and reduce the thermal deformation of machine tool, must carry on the cooling process, and to be able to automatic chip removal in a timely manner; For heating a big place, should step up its heat dissipation area, improve heat dissipation or disposed of by thermal insulation. User training should also be prepared to factory acceptance machine tools, the user right, the rational use of machine tools, regular maintenance of machine tools, it is very important to improve the numerical control lathe accuracy stable.