Fundamental Study On The Rotational Indexing Machining Technology Of Straight Bevel Gear

Bevel gears are the indispensable part to transmit the movements of intersectingaxes. Since it is easier to design and manufacture, the straight bevel gear is widelyused in cars and machine tools. But at home, it is still mainly machined by traditionalmechanical machine tools with intermittent indexing methods and lower productionefficiency. The study on the new machining technology is less, which greatly limitsthe development of straight bevel gears. Based on the principle of cycloid rotationalindexing, a rotational indexing machining method is proposed in this paper to realizethe continuous indexing machining of straight bevel gear.Firstly, with the study on machining of rotational indexing and epicycloid bevelgear, the principle of rotational indexing machining of straight bevel gear is explainedby the mathematical method of space curve approximating straight line. On this basis,the mathematical model of rotational indexing machining is established and thecutting point trajectory is obtained. The parameters are optimized and adjustedaccording to approximation straightness of curve segment to generatrix on toothsurface. Then tooth surface of straight bevel gear is gotten with the forming method,and the modification shape of cutting edge is undertaken to reduce tooth surface error.Meanwhile, adjustment parameters of machine tool and machining parameters aregiven. Through the transformation of motions, the rotational indexing machining canbe done on Free-form NC machine tool. Finally, by means of calculation andnumerical simulation of an example, the correctness and feasibility of the machiningmethod for straight bevel gear is proved.The rotational indexing machining method of straight bevel gear proposed in thispaper has got rid of the generating gear, making the process of machining andcalculation easier to be understood. It can also realize continuous indexing machining,which can greatly improve the production efficiency. At the same time, the study laysthe foundation for design of new straight bevel gear machine tools. And it will alsoimprove the domestic machining situation and promote the progress of manufacturingtechnology for straight bevel gear.