Brushless dc motor controller can appear in the process of using the gear precision is not accurate phenomenon, that we should take what kind of method to improve the accuracy? The following knowledge will be detailed introduction for you, please remember: 1, gear hobbing machining accuracy analysis: main shaft gear precision and movement precision, stability and related contact precision precision. Rolling processing with control the common normal length and tooth circle diameter jump to ensure accuracy of movement, with control of tooth profile error and base pitch deviation to ensure accuracy of working stability, control gear to error to ensure that the contact accuracy. 2, gear ring, the radial runout error: gear ring gear radial runout refers to the a transfer within the scope of probe on the tooth or tooth groove, contact with the school is double sided, probe axis is the measure of the change of the relative to the gear. Is tooth gear ring relative to the eccentric shaft centerline, the eccentric is because when installing parts, parts of the two center hole and the rotary center of the workbench installed do not overlap or deviation caused by too much. Make the bad or for the top and the top hole, make a poor positioning surface contact eccentric, so gear ring diameter jump above should be main reason analysis to solve. The solution is not only a, so we should be analyzed from several aspects, looking for a variety of solutions, thus fundamentally solved the problem.