High-precision air floatation electric main shaft

Abstract

The invention relates to a high-precision air floatation electric main shaft. A rotor shaft is arranged at one end of an air floatation bearing through an air floatation main shaft, a motor rotor is connected with the rotor shaft, a stator is fixedly arranged on a motor jacket through a water jacket, one end of the air floatation bearing is fixedly arranged on the motor jacket, the other end of the air floatation bearing is fixedly arranged on a bearing press plate, and the bearing press plate is fixedly arranged on a main shaft box body. The rotor shaft is connected with the air floatation bearing. The realization modes of direct drive motor driving, rotary encoder feedback and computer digital control are adopted. The high-precision air floatation electric main shaft has the advantages that one end of the main shaft can be fixed, the thermal expansion of the main shaft extends in a direction far away from a workpiece, in addition, the structure is compact, the processing and assembly regulation difficulty of each part is reduced, and the installation is convenient. The design precision of the air floatation main shaft is shown as follows that the positioning precision is 2.5 angular seconds, the repeated positioning precision is 1 angular second, and the rotary error is smaller than or equal to 0.3 mu.m.

Description

technical field [0001] The invention relates to an electric spindle used in ultra-precision machine tools, in particular to a high-precision air-floating electric spindle. Background technique [0002] The workpiece spindle directly affects the movement of the workpiece during the machining process, so the rotation accuracy of the workpiece spindle directly affects the machining accuracy of the workpiece. Its accuracy and characteristics can evaluate the accuracy of the machine tool itself. Compared with the air bearing, the transmission rolling bearing has more error links. The precision is not high, and the calorific value of the rolling support is much greater than that of the air bearing. When the processing object is a precision free-form optical element, it is difficult to meet the requirements for surface accuracy and surface finish of the workpiece. The thermal deformation of the machine tool spindle rotation system caused by the air bearing is small, and it has goo...

AI Technical Summary

Problems solved by technology

[0002] The workpiece spindle directly affects the movement of the workpiece during the machining process, so the rotation accuracy of the workpiece spindle directly affects the machining accuracy of the workpiece. Its accuracy and characteristics can evaluate the accuracy of the machine tool itself. Compared with the air bearing, the transmission rolling bearing has more error links, The precision is not high, and the calorific value of the rolling support is much greater than that of the air bearing

When the processing object is a precision free-form optical element, it is difficult to meet the requirements for the surface shape accuracy and surface finish of the workpiece

The thermal deformation of the machine tool spindle rotation system caused by the air bearing is small, and it has good rotation accuracy. The pressure film supporting the rotary shaft in the bearing can play a homogenizing effect. In addition, the air bearing spindle also has good dynamic characteristics, long precision life, and no vibration. and other advantages, so although the stiffness of the aerostatic bearing is low, it is very suitable for ultra-precision machine tools for micro-cutting

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