Research On Heating Problem Of CNC High-speed Ball Screw Feeding System

Numerically-controlled machine tool's ball screw feeding system assumes the cutting machine, its performance directly influence the whole machine running and precision. Due to the exaltation of the speed, contact area (screw nut, bearing etc) of ball screw feeding system produces a large number of hot, and these heat can not send out in time, the temperature of the ball screw will increase, causing the ball screw thermal deformation, and then changed the workpiece and the relative position of the tool, making the machining accuracy decreased, so the study of temperature rise and thermal deformation of ball screw laws to improve the machining accuracy has important significance. In view of the above questions, this article have a study of machine high-speed hollow cooling ball screw temperature field and thermal deformation of mathematical model and boundary condition calculation, thermal characteristic analysis. Main contents are as follows:1. Established a three-dimensional temperature field mathematical model of ball screw feeding system, and based on elastic mechanics, the basic equations of thermal deformation finite element theory established the mathematical model of the thermal deformation.2. Established a three-dimensional CAD model of ball screw systems, and the combination of finite element mesh and thermal contact between the conductive surfaces are discussed.3. Based on the analysis of internal heat and boundary conditions of the ball screw system, established the temperature field finite element model of ball screw system. Based on the finite element method, transient and steady temperature field of ball screw system are analyzed in detail, and build a high-speed, high acceleration of feed system of temperature control platform, ball screw feeding system for experimental analysis of the temperature under the high-speed condition, and the experimental measurement results were compared with theoretical results.4. In determining the constraint condition and heat load, the steady temperature as the heat load added to the ball screw feeding system finite element model, a detailed analysis of the thermal deformation of ball screw system is done, and carried out the picture of the thermal displacement of ball screw system. Build a high-speed, high acceleration of feed system of temperature control platform, ball screw feeding system for experimental analysis of the thermal displacement under the high-speed condition, the theoretical model will be verified by comparing experimental data and theoretical analysis is correct.