Computer program in Visual Basic language for simulation of meshing and contact of gear drives and its application for design of worm gear drive

摘要

The authors propose: (i) enhanced computer program for simulation of meshing and contact of gear drives; (ii) application of computer program for analysis of worm gear drive; and (iii) advanced design of worm gear drive with reduced transmission errors and favorable bearing contact. The output of Tooth Contact Analysis (TCA) program are: function of transmission errors, path of contact and bearing contact. The program is written in Visual Basic language and enables to combine numerical computation and graphical illustration. The improved design of worm gear drive is based on application of an oversized hob and modified worm generated by varied plunging of the generating tool. It is discovered that worm generation without tool plunging may cause positive transmission errors, unacceptable for favorable conditions of force transmission. Positive transmission errors are the herald of possible surface interference. A predesigned parabolic function of transmission errors is provided in order to absorb transmission errors caused by errors of alignment and reduce the level of vibrations, especially in the case of application of multithread worms. The investigation is accomplished for a worm-gear drive with the Klingelnberg type of the worm that is ground by a circular cone, but the proposed approach may be applied for other types of worm gear drives with cylindrical worms.