The Mechanism Of Gear-Honing And Dynamic Simulation Analysis With Electroplating CBN Hard Honing Wheel

The research and application of gear innovative manufacturing technologies is key to improve the transmission quality of gear. Gear tooth shape and pitch error, will be directly affecting their ability to transfer torque. Tooth surface morphology of micro-geometry will be greatly influencing the noise of transmission, performance and life in the use. In order to improve the existing gear bearing ability, the hardened tooth surface technology is used by many countries, that is by increasing the hardness of tooth surface to reduce device size.For quench hardened involute gear finishing, our current method is to use grinding or soft gear-honing. Although the grinding process can meet the precision of tooth profile, but its low productivity, high cost, leading to less competitive, and the tooth surface morphology of micro-geometry is not conducive to reducing the transmission gear noise. The matrix of soft honing wheel is elastomer, resulting in its static accuracy will be decreased, and tend to obey the precision of gear blanks, causing instability of soft gear-honing processing quality.With superhard materials of cubic boron nitride (CBN) and the metal plating on the steel matrix, made-up electroplated CBN hard wheel, because its rigidity matrix is a very good, making surface quality of gear to be machined could not only improve, but also the profile error and lead error, the cumulative pitch error and other can be corrected, processing efficiency will be improved significantly.However, for various reasons, hard honing wheel with electroplated CBN finishing on the quenching hardened gear, there are many problems that must be explored and resolved, gear-honing mechanism of hard honing wheel and the process techniques of hard honing wheel has not been satisfactorily resolved. In the paper, some depth investigation and some useful results were gotten, for the promotion of electroplating CBN hard honing wheel on the quench hardened gear finishing technology has important practical significance.This article was the following areas:Based on the gear meshing, differential geometry, grinding, friction, elasticity and other theories, educed out calculation model of honing cutting depth, and given out the calculation method of various parameters in the model, realized the theoretical prediction on the tooth profile error, revealed the internal formation factors of the tooth profile error (such as the concave and the dig root error) in gear-honing processing, all of thus match to the practice.The parametric modeling of gear-honing wheel and gear, and parametric assembly were achieved, the involute constructed of tooth surface of honing wheel was converted into spline, and the fit points on the spline was parameterized, for honing teeth surface modification optimized was possible.By the dynamic finite element analysis software, according to the actual processing conditions setting the model boundary conditions, the dynamic simulation of gear-honing process was done with electroplating CBN hard honing wheel, through the tooth contact stress data collection, contact stress distribution at engaging points has been drafted, further revealed the internal factors of the tooth profile error caused by the tooth surface contact stress fluctuations, also revealed changes in profile error caused by the difference of contact ratio for the different number of teeth. By the static finite element analysis, revealed the gear surface normal deformation trend, it also revealed the profile error in the other side.In the help of finite element analysis and optimization software, the tooth surface of honing wheel was optimally modified, through regression analysis of the sample points, the value of the best parameters to modify tooth profiles were obtained, back to the CAD model of honing wheel, the tooth surface modification of the honing wheel was achieved, tooth surface contact stress distribution had been greatly improved, as the guide provided a strong guarantee for the production practice.With electroplating CBN hard honing wheel, studies show that on the tooth middle (especially when there are fewer in number of teeth), fluctuations due to contact stress will result in tooth "concave" error, and in parts of the tooth root, as honing cutting the maximum slip distance, contact stress is also larger and have a "dig root" error, in the honing wheel production, these factors should be considered to achieve the lower profile error and increase the quality of the purpose of honing process. There is no doubt that these findings have important guidance to production practice.