The taper shank shaper cutter is mainly used for machining internal meshing spur and helical gears.
In order to generate the relief angle and not affect the tooth shape of the processed gear after regrinding, the shape of a displacement gear is made in each section perpendicular to the axis of the gear shaper. The displacement coefficient X0 gradually decreases from the front end to the rear end surface, and from positive to negative. Taper shank shaper knives have some limitations in use.
1.Restriction of gear undercut: When the tooth top of the gear shaper cuts into the involute tooth shape of the root of the gear to be cut during the cutting process, it is called undercut. The less the number of teeth of the gear to be processed, the greater the possibility of undercut .
2.The limitation of gear top cutting: Top cutting refers to the phenomenon that the tooth top of the cut gear enters the tooth shape of the root of the gear shaper and is cut off.
3.Restriction of gear transition curve interference: When the gear shaper is cutting teeth, it cannot cut out the involute tooth shape on the entire tooth surface, and the transition curve is at the root of the gear. The smaller the number of teeth of the gear shaper and the larger the coefficient of tooth profile deformation, the longer the transition curve will be. If the tooth tip of the paired gear contacts the transition curve, interference will occur.
4.For the gear shaper for processing internal gears, the limitation that the top cut does not occur during the radial cutting process of the gear shaper should also be considered.
According to the international standard, the precision of the standard gear shaper cutter is divided into 3 types: AA grade, A grade and B grade. In order to process the gears that need to be re-shaved or ground, the pre-shaving or pre-grinding gear shapers should be used respectively to leave a certain machining allowance on the gear tooth surface. Therefore, the tooth shape of these gear shapers needs to be specially designed.