Research On Photo-Electric System Of Rotating Shaft Radial Runout And Rotary Speed Real-Time Measurement

Since 1960's, the precision required for processing parts has continually improved as a result of development of space technology, computer technology and so on. But radial runout of a high-precision machine tool is one of the most important factors which influence the precision of processing parts. For steamships and gas turbines, radial runout is also the key parameter of running safely and steadily. Also rotary speed is an important parameter of rotary mechanical equipment.In allusion to deficiencies of traditional sensors, a project based on reflex fiber-optic sensor to measure radial runout is proposed. The technology based on optical fiber to measure displacement has many merits which normal measure technologies do not have, such as better capability of resisting strong electromagnetism interfere, flexible bend, even it can work in some special conditions. For rotary speed, a method of using photoelectric coder which is easier and more precise than traditional methods is proposed.This paper studies on radial runout and rotary speed measurement of rotary shaft, which involves these aspects: development situation and principles of radial runout and rotary speed measurement; measurement principle of reflex fiber displacement sensor which belongs to the measurement system of radial runout; research and design of hardware circuit of the system of rotary speed; design of software; experiment data processing, error sources analyses, and presenting advice for system enhance.Considering radial runout measurement, LD soft-startup circuit and constant luminance control circuit have been adopted. Considering rotary speed measurement, SCM (Single Chip Micyoco) is used as the main control chip and Schmitt trigger is also chose to plastic the signal coming from photoelectric coder for ideal pulse signal. SCM enhances the precision of the rotary speed measurement system.Considering software, Visual C++ is chose as the development platform. The software can process data, store and display the measuring results. Measuring result is displayed intuitionally in form of graph. The photoelectric radial runout measurement system designed for rotary shaft, can better resist strong electromagnetism interfere and have high precision. The software can measure real-time, process and store data fast, display measuring result with dynamic graph. The rotary speed of rotary shaft measurement system is easy to realize and has high precision. Experiments have shown that the relative error of the radial runout measurement system's static stability less than 0.53% and its sensitivity can reach 1.38μm/mv; the relative error of the rotary speed measurement system is 0.13% which achieves design demand.