Research On Generation Mechanism And Correction Technique For Spiral Bevel Gear's Grinding Errors

Spiral bevel gear is the mechanical transmission fundamental element.Its space shape and the machining process are very complicated.The developments of numerical control technology provide convenience for simplification adjustment and improvement processing quality of spiral bevel gear.But the quality control of spiral bevel gear processing has been the key problem in the processing.At present,the quality control technologies of spiral bevel gear NC processing are grasped only the minority companies in overseas and are still at the starting stage in domestic. Therefore,according to the numerical control processing characteristic of spiral bevel gear,taking increase processing accuracy as the goal,the paper carries out research in mechanism and compensation technology of spiral bevel gear grinding error.The concrete contents are as follows.Study on the numerical control processing model and machining method of spiral bevel gear.Combined with relative derivation and the partial conjugate law, both the generated method and formatted method of gear were analyzed,both the tilted method and modified roll method of pinion were also analyzed.According to machining characteristic of a cradle-type universal machine,the six axis five linkage numerical control machining model of generated method,formatted method,tilted method and modified roll method were established.The above research provides theoretical basis for analysis of spiral bevel gear grinding error and correction tooth surface error.Study on the synthesis error model of spiral bevel gear numerical control grinder with six axes five linkages.Based on the multi-body system theory and homogeneous coordinate matrix transformation method,the low foreword body array topology structure of spiral bevel gear CNC grinder was studied.The mathematical model of synthesis space error of spiral bevel gear CNC grinder was established,and the erroneous expressions of six degrees of freedom direction were obtained.Based on such expressions,the tool point erroneous change laws of spiral bevel gear machine with six axes five linkages were analyzed,and the influence of the grinding spot errors on the teeth pitch,helix angle,pitch,teeth profile and others was discussed.The control conditions of machine's key error were proposed to obtain the precise form and position parameter of spiral bevel gear.Study on the effect of machining errors of spiral bevel gear-tooth surface.Based on the model of error synthesis,the tooth surface equation of spiral bevel gear including the error motion for machine tools was further proposed by the manufacture principle and meshing principle of spiral bevel gear.The simulation of tooth surface with or without error motion of the spindle was carried out and the difference surface was also obtained,then the effect of error motion of the spindle for tooth surface was analyzed.Based on the forming processing principle of spiral bevel gear and space coordinates transformation,the tooth surface equation using forming processing was build.The difference surfaces with the disturbances of each machine tool adjustment parameter were studied,and the influence law of machine tool adjustment errors on tooth surface errors was analyzed.The above research finds out the influence of grinder error and machining setting parameter error on tooth surface error of spiral bevel gear.Study on the error correction technique of tooth surface using truncated singular value decomposition(TSVD).The error correction model of tooth surface was established by machine tool adjustment parameters and meshing principle.The solution to these linear transcendental equations based on regularization method of truncated singular value decomposition and L-curve method was proposed,while the tooth surface errors were corrected and the solving precision is higher than that using the least square method.The above research provides effective method for high precision correction of tooth surface error.Experimental study on the error correction of spiral bevel gear.The error correction model of tooth surface and solving method using TSVD were verified experimentally,and the tooth surface machining quality of spiral bevel gear was improved.In addition,the change tendency of the pre and post correction of five axes linkage expression coefficients was analyzed,and the influence of change tendency on tooth surface geometrical error was also discussed.