Analysis And Experimental Research For High Speed Motorized Spindle Thermal Properties

With the development of modern high-speed machining technology, high-speed spindle technology has been widely used. As a core component of high-speed machine tool, high-speed motorized spindle realizes"zero transmission"of machine tool, simplifies its structure and increases its response. However, the heat generated will lead to the stability of spindle. The friction heat of bearing and the electromagnetic loss heat of built-in motor will cause thermal deformation of spindle, which will reduce the machining accuracy of machine tool and affect the speed improvement of high-speed motorized spindle. Compared with the ordinary motor, the thermal properties of high speed spindle have more complex dynamics and instability. In order to effectively analyze the thermal properties of motorized spindle, we select grinding spindle which maximum speed is 60000r/min, analyse its thermal properties by using finite element method and carry out experimental study of temperature rise. The main works are as follows:â‘ The structure characteristics and working principle of motorized spindle are Described detailedly, and some key technologies which include bearing technology associated with the thermal performance, lubrication technology, cooling technology and spindle drive technology are analysed.â‘¡The friction power loss of bearing and the electromagnetic loss of built-in motor are calculated respectively, and the heat transfer and heat dissipation law of motorized spindle system are analysed, in addition, the thermal boundary conditions of motorized spindle are determined , and some laws that various factors affect the thermal properies of motorized spindle system are analysed theoretically.â‘¢The classical heat transfer theory, the basic knowledge and steps of ANSYS thermal analysis are described, and a high-speed spindle finite element model is established and solved, and temperature distribution and change law of thermal properties of motorized spindle under thermal equilibrium are obtained.â‘£In order to verify the conclusion of the previous chapter, related temperature rise experiments of motorized spindle are carried out. The experimental test equipment and test methods are described, and the experimental testing process and related notes are described detailedly. In addition, the experimental data obtained are analysed and some methods which improve thermal properies of high-speed motorized spindle are proposed, which provide the basis for structure design, parameter optimization and dynamic analysis of motorized spindle.