求教：此类直角铣头内部传动构造？

求教此类直角铣头内部传动构造主轴那块我还能理解但是直角传动是靠怎么方式实现的？伞齿轮，蜗轮蜗杆？还是其他方式？ $("flv_huc").innerHTML=(mobileplayer() ? "" : AC_FL_RunContent("width", "500", "height", "375", "allowNetworking", "internal", "allowScriptAccess", "never", "src", "https://player.youku.com/player.php/sid/XMzUwMTE1MDk2.html/v.swf", "quality", "high", "bgcolor", "#ffffff", "wmode", "transparent", "allowfullscreen", "true"));