| 摘要 |
PURPOSE:To machine the tooth surface and root of a workpiece gear in a continuous surface with no boundary step by simultaneously generating a finish cut on the tooth surface and root of the workpiece gear by a single finishing carbide hob. CONSTITUTION:Each cutting edge 1 is composed of a tooth surface generating portion 1a and a root generating portion 1b located at the top end of the generating portion 1a. In other words, the generating portion 1a has side cutting edge ridges 1c for cutting the tooth surfaces of a workpiece gear, while the generating portion 1b has a tip cutting edge 1d for cutting the roots of the workpiece gear. The rake surface of the generating portion 1a is flat and its rake angle alpha1 is set between -15 deg. and -60 deg., while the rake surface of the generating portion 1b is flat and its rake angle alpha2 is set between 0 deg. and -10 deg.. This construction allows a single hob to perform a simultaneous machining of the tooth surface and root of a workpiece gear and to machine them in a continuous surface with no boundary step therebetween. |
