外啮合直齿插齿刀设计的关键是确定其最大变位系数X_((?)max)和最小变位系数X_((?)min)。前者必须在保证插齿刀有足够齿顶厚度的前提下,不使工件发生过渡曲线干涉。后者必须在保证工件不产生根切和顶切的前提下,使插齿刀有足够的可磨宽度B_(?)。利用计算机和表3所示程序能够一举解决所有上述问题,并能迅速优选出最佳参数。下面叙述该程序的编制原理。(符号含意:m—模数、α—齿形角、z—齿数; The key to the design of external gear shaper is to determine the maximum displacement coefficient X _ ((?) Max) and the minimum displacement coefficient X _ ((?) Min). The former must ensure that the gear shaper cutter tip enough thickness under the premise of the transition curve does not make the workpiece interference. The latter must ensure that the workpiece does not produce undercuts and top cut under the premise of the shaper cutter enough grinding width B_ (?). Using the computer and the program shown in Table 3, it is possible to solve all of the above problems at a stroke and to quickly optimize the best parameters. The following describes the preparation of the principle of the program. (Symbol meaning: m-modulus, α-tooth angle, z-tooth number;