Roundness measuring system for small balls

小球圆度测量系统

基本信息

批准号：
10650145
负责人：
MIZUMOTO Hiroshi
金额：
$ 2.18万
依托单位：
Tottori University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
1998
资助国家：
日本
起止时间：
1998 至 1999
项目状态：
已结题

项目摘要

An aerostatic bearing with active inherent restrictors is developed for the main spindle of a roundness measuring system planned to measure small balls. The active inherent restrictor (abbreviated AIR) was invented by the head investigator, and incorporated into several aerostatic bearings and guideways for improving their performances. The AIR consists of a piezoelectric actuator having a through hole, one end of the hole is small enough to function as an orifice when the actuator is embedded in the bearing surface. When a sensor detects the change in the air gap on the bearing surface, a computer of the AIR-control system calculates the supply voltage for the piezoelectric actuator to change the pressure on the bearing surface, and to reduce the displacement and vibration of the main spindle. The major specification of the aerostatic bearing for the main spindle is as follows : the outer diameter is 140mm and the height is 86mm. There are eight AIRs on each radial and thrust bearing surface.Without using the active control system, the rotational accuracy of the main spindle is about 0.2mm. Active control using the AIR improves the rotational accuracy to be 20-30nm. The frequency response of the bearing with the AIR shows that the effect of the AIR on the dynamic stiffness of the bearing can be seen in the low frequency range (less than 20Hz). However, the measured rotational accuracy is not enough for the main spindle of the roundness measuring machine because the planned resolution of the roundness is 1nm. The main reason of the lack in the rotational accuracy is the geometrical error of the bearing surface on the spindle. Several efforts have been performed to improve the geometrical accuracy, however, the rotational accuracy of the main spindle can not be improved.

为计划测量小球的圆度测量系统的主要主轴开发了具有主动固有限制器的空气轴承。主动调查员发明了主动固有的限制器（缩写空气），并将其纳入几个空气稳定的轴承和指南中以改善其性能。空气由具有贯穿孔的压电执行器组成，当执行器嵌入轴承表面时，孔的一端足够小，可以作为孔口起作用。当传感器检测到轴承表面上的气隙变化时，空气控制系统的计算机计算了压电电执行器的电源电压，以改变轴承表面的压力，并减少主纺锤体的位移和振动。主轴的空气固定轴承的主要规范如下：外径为140mm，高度为86mm。每个径向和推力轴承表面上都有八个空气。没有主动控制系统，主主轴的旋转精度约为0.2mm。使用空气的主动控制提高了旋转精度为20-30nm。轴承与空气的频率响应表明，在低频范围（小于20Hz）中可以看到空气对轴承动态刚度的影响。但是，测得的旋转精度不足以用于圆度测量机的主要主轴，因为圆度的计划分辨率为1NM。缺乏旋转精度的主要原因是主轴上轴承表面的几何误差。为了提高几何准确性，已经进行了几项努力，但是，无法提高主轴的旋转精度。