已知压力角α为20°的公制蜗杆，轴向摸数m=3，外径d=42mm，求牙型角d，中径d 发布时间：2018-07-02 20:36 │ 来源：www.tikuol.com 题型：问答题 问题： 已知压力角α为20°的公制蜗杆，轴向摸数m=3，外径d=42mm，求牙型角d，中径d2，内径d1？
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