Design And Study Of Microcomputer Aided Dynamic Acceptance Test System For Lathe

Dynamic performance of lathe mainly refers to the capacity of lathe's resistance to vibration, including resistance to vibration and stability. As the lathe is being developed into the direction of high speed, more accuracy, high efficiency etc, the requirement for machining performance of lathe improves constantly, thus, which leads to the requirement for dynamic performance of lathe also becomes higher and higher. Therefore, it is necessary to make the dynamic acceptance test for lathe.This paper is to design and implement a relatively simple dynamic acceptance test system for lathe. The system is based on the principle that flexibility frequency characteristic is used to evaluate dynamic performance of lathe. And pulse exciting means is employed as test method. The hardware of the system is built upon the general computer, including pulse hammer, electric charge amplifier, piezoelectricity sensor, A/D convertor etc; the software is the specific program that is developed with C++ language on our own. The following function modules are included: data sampling, signal analysis and processing, waveform display, file store, etc. The whole system implements functions such as signal sampling of pulse exciting force and the consequential responsive displacement, data store, display of waveform in time domain, spectrum chart, accordingly acquire the maximum of negative real part of lathe's dynamic flexibility. The dynamic performance of lathe is evaluated based on it, the larger its value is, the worse lathe's dynamic performance is.In order to verify the correctness and stability of the system, a pulse exciting experiment is made on a C618K-3 type of general lathe. On the recommendation of BAS and UMIST, excitation is made in the direction of simulative cutting force, and the consequential response is picked in the direction of penetration of the cutting tool. Then the workpiece, which is Φ70×l20mm and is clamped by the lathe's chuck is made excitation, finally, cross dynamic flexibility is evaluated and the dynamic performance of lathe is appraised. The conclusion demonstrates: the results acquired by this system and professional dynamic analysis instrument are approximately equal.The cost of test may be much cheaper using this system due to its utilizinggeneral computer and specific analysis program, compared to the costly professional analysis instruments. It is feasible to evaluate lathe's dynamic performance using this system and give reference to users that want to understand and appraise the comprehensive performance of lathe.