Research On Pitch Processing Technology Of Ultra-precision Gears Based On End-tooth Indexing Table

The gear industry of China is rapidly developing and has become a great country of gear manufacturing during the period of "11th five-year plan". But in term of overall there is still a big gap with the developed countries such as America, Germany. The gear and its transmission is still the key of the development in the12th five-plan. Gear precision level is an important symbol of one country’s gear industrial level. How to processing the ultra-precision gear, has become the problem to be solved urgently. In this paper, based on the end-tooth indexing technique, we make a deep exploration and research on the issue that how to improve the dividing precision of gear grinding machine and to realize the ultra-precision gear processing which pitch accuracy is level1or above.Detailed understanding the features of end-tooth indexing technology and its advantage in the field of precision machining, and the latest development of the status quo in gear grinding machine dividing technology and the pitch measurement technology at home and abroad. On the basis of the existing conditions of the laboratory, there was about several aspects of the study:(1) The test determines using high precision end-tooth dividing table modification Y7125gear grinding machine dividing mechanism through the study of the theory of the end-tooth indexing technique. After testing, the indexing precision of the end-tooth dividing table under Free State was0.51±0.15"(2)Designed the automatic dividing mechanism of end-tooth dividing table, and realized the installation of end-tooth dividing table on the machine in theory. Studied the error of end tooth dividing table during the installation of the matching, and put forward to solving the solution of end-tooth dividing table installation error.(3)The modification for indexing system of the Y7125gear grinding machine is success, and the dividing error of the modified machine is measured. After measuring, the indexing accuracy of the machine is1.88±0.31".It reached the requirement of processing gear which pitch precision is1or above.(4) With the No.4006standard gear after grinding, for example, measure the standard gear tooth pitch deviation. After measurement, the pitch accumulated deviation of left tooth Fp=1.77μm, the largest single pitch deviation fpt=1.13μm. the pitch accumulated deviation of right tooth Fp=2.05μm, the largest single pitch deviation fpt=1.20μm.By the above knowledge, after processing, the No.4006standard gear pitch accuracy has reached the level1or above.Verified the Y7125gear grinding machine tool modified success, realized the level1or above pitch accuracy of ultra-precision gear processing, and laid the foundation of a new indexing technology in the machine tool industry of our country.