Modeling of a Involute Gear Based on the Generating Principles of Involute Helicoid

An approach for modeling the involute gear teeth profile based on the generating principle of involu-tehelicoid was put forward for solving the problem of presently using complex modeling procedure.One of the major characteristics of involute helicoid,the intersection of the helicoid and a transverse plane is an involute curve,is used as the new modeling procedure.The intersection curve is employed directly as part of the involute gear profile and combining the basic parameters of a involute gear,the whole profile of the gear can be formed and thus the modeling of a whole gear can be realized by extrude or sweep along a helix curve.A procedure as well as some key techniques for modeling gear,taking a spur as an example,is introduced and discussed in detail in this paper and a truly procise modeling is achieved by the approach.