精选优质文档-倾情为你奉上EXTERNAL SPUR GEAR DATA（外圆柱齿轮参数）manufacturing data（制造参数）part number（零件号）tooth form（齿面）gear type（齿轮类型）number of teeth（齿数）normal module（法向模数）normal pressure angle (at ref circle)法向压力角（在分度圆上）helix angle (at ref circle)螺旋角（在分度圆上）helical lead（螺旋导程）hand of helix（旋向）reference face width（参考齿宽）outside diameter（齿顶圆直径）chamfer diameter（倒圆直径）reference(pitch)circle diameter（分度圆直径）或节圆start of active profile diameter有效渐开线起始圆直径form diameter 展成直径root diameter
