Study On Grinding Method Of Epicycloidal Spiral Bevel Gears

With the characteristic of large transmission ratio,high transmission stability and long service life,spiral bevel gears is widely used in the transmission between non-parallel axes.They are divided into two types of spiral tooth spiral bevel gears and epicycloidal spiral bevel gears.Among them,the epicycloidal spiral bevel gear can finish the roughing and finishing process of all gear tooth surfaces in a single clamping because of its continuous indexing processing mechanism which makes it more efficient in processing and more powerful in transmission performance.However,the epicycloidal spiral bevel gear also has the disadvantage of not grinding teeth.The tooth surface accuracy is usually damaged to a certain extent after the heat treatment,and the tooth shape cannot be accurately corrected,making it difficult to completely realize its advantages.In this paper,the basic machining principle of the face hobbing method is used to analyze the shape of the epicycloidal tooth surface for the situation where such teeth cannot be ground.Using differential geometry to analyze the mathematically feasibility of grinding processing,and according to the theory of the continuous indexing movement,a method was studied and explored aiming at obtaining a shape of the epicycloidal tooth without damage,with high precision and adaptability in batch production,can use a single pass to process the entire tooth surface of the tooth surface for different forming methods.The research completed in this paper is as follows:1.Based on the analysis of the principle of continuous indexing on the face hobbing process,the method for solving the tooth surface equations and the coordinates of the discrete points on the tooth surface of the spiral bevel gear of the cycloidal gear is deduced.On this basis,the geometric characteristics of the tooth surface is analyzed and the three-dimensional gear model can be established.2.According to the formation mechanism of the epicycloidal tooth surface,the method of formed epicycloidal tooth grinding is proposed.The calculation of grinding wheel design parameters and the interference analysis of the working face and non-working face of the wheel while grinding were performed,and the method of solving expand correction parameters of the grinding wheel was modified according to the interference condition.3.According to the idea of single tooth indexing of spiral bevel gear and optimization calculation method,using a rotary body in space to replace the generating gear of face hobbing method with low replacement error and calculated parameters of single tooth processing afterwards.Using the flexibility of the machine tool,introducing high-order motion parameters to modify the tooth grinding movement,the processing parameters that can effectively reduce the substitutional deviation are solved.Based on this,the theoretical deviation of the full tooth surface is calculated and the control of the replacement tooth surface deviation is realized.4.The calculation method of the tool position of the traditional mechanical machine tool and the tool position transformation method of converting the coordinate system of the left and right rotary components to the structure of the full CNC machine tool are studied.The relevant solid three-dimensional model was built in the simulation software to carry out tooth grinding simulation experiment,which verifies the correctness of the machining motion control method.