在设计直齿内齿轮插齿刀时,合理选择变位系数是一项主要的工作,当选用较大变位系数时可以增加插齿刀的刃磨次数,增加插齿刀的使用寿命,但是(一) 随着变位系数的增加插齿刀的齿顶将变尖,会加快刀具的磨损,降低耐用度。(二) 用变位系数大的插齿刀加工内齿轮时,在插齿刀切入进刀时,插齿刀的齿顶会将齿轮的齿顶角切去,发生切入顶切现象。(三) 用变位系数大的插齿刀加工出的内齿轮,在与配对齿轮啮合时会发生过渡曲线干涉现象。(四) 用变位系数大的插齿刀加工内齿轮时,插齿刀和内齿轮发生负的啮合角,不能得到正常的啮合。因此,在设计插齿刀时,应在上述四个限制条件允许的情况下,尽可能 In the design of spur gear internal gear shaper, the rational choice of displacement coefficient is a major task, when using a larger displacement coefficient shaper cutter sharpening can increase the number of times to increase the gear shaper life, but (A) As the coefficient of variation increases, the tip of the gear shaper will become sharp, which will speed up the tool wear and reduce the durability. (B) with a variable coefficient of gear shaper cutter processing internal gear, when the gear cutter cut into the knife, the gear tooth tip crest will cut off the gear, the occurrence of cut into the top cut phenomenon. (C) the use of gear with a large coefficient of gear shaper cutter out of internal gear, meshing with the mating gear transition curve occurs when the interference phenomenon. (D) with a variable coefficient of gear shaper cutter processing internal gear, gear shaper and internal gear negative engagement angle, can not get the normal meshing. Therefore, in the design of gear shaving cutter, should the above four conditions allow, as far as possible