Research Of On-machine Measuring System For Spiral Bevel Gears

With smooth transmission performance and high bearing capacity,spiral bevel gears have been widely applied in mechanical transmission systems.The machining precision of gears is critical to its meshing transmission state,efficiency and working life,and error measurement is essential to ensuring the precision of gears.On-machine measurement can effectively avoid the benchmark misalignment error and gear secondary installation error caused by special measuring instruments,of which the inspection results are helpful to the machining parameter modification,and are significant to improve gear machining precision,reduce cost,shorten the machining cycle.Based on five-axis NC mchine tool,this paper has established the measuring model and analyzed the measuring method for spiral bevel gears,which has been verified by experiment,proved to be correct and can greatly enhance the measuring efficiency.The main work is as follows:Based on the present modeling methods for tooth surface of spiral bevel gears and the principle of spherical involute,the equations of tooth surface shape and vector have been derived;Also measuring grid division of tooth surface and three-dimensional geometric modeling have been completed.According to the error measurement standard of spiral bevel gears,the paper has analyzed the error measurement principle and method of tooth shape,longitudinal form and the pitch for spiral bevel gears.Then measurement model has been established based on the five-axis NC machine tool.At last,the positioning and measurement path planning as well as Vericut simulation of measurement process have been accomplished.The working principle of the trigger probe has been analyzed,and the on-machine measurement system has been constructed based on the five-axis NC machine tool.contraposing the errors of the gear,this paper has designed the NC measurement program and implemented the measuring experiment.Then the error evaluation principles and processing methods have been studied and analyzed.With the error evaluation conducted,the results showed the correctness of the measuring method.On-machine measurement software system of spiral bevel gears has been developed by Visual Basic,also realized functional modules such as parameter setting,theoretical calculation,measurement program generation,error measuring and data processing.The algorithm of the software is realized by hybrid programming of VB and MATLAB,that is dynamic link library.With the whole work integrated into the software system,a set of complete system from theoretical calculation to error processing has been formed.