A handle arm mounting structure 9 for a spinning reel includes a fastening section 25a and a washer member 27. The fixing section has a first non-circular hole 25c configured to engage non-rotatably with a non-circular section of a handle shaft. The washer member has a circular disk-like section 27a and an engaging protrusion 27b and is configured to be mounted in an axial direction of the handle shaft. The circular disk-like section has a second non-circular hole 27c configured to engage with the non-circular section. The engaging protrusion is arranged to protrude toward the first non-circular hole from a periphery of the second non-circular hole. The engaging protrusion has an inside surface 27d configured to engage with the non-circular section and an outside surface 27e having a first tapered surface 27f configured to taper toward a tip end and to engage with the first non-circular hole.對於釣魚用捲線器的操作桿臂安裝構造,可抑制操作桿臂的遊動。操作桿臂安裝構造(9),是藉由固定螺栓(35)將操作桿臂(25)安裝在一端形成有非圓形部(24b)的紡車式捲線器的手把軸(24)的構造,具備固定部(25a)及墊圈構件(27)。固定部是具有可一體旋轉地卡合於非圓形部的第1非圓形孔(25c)。墊圈構件,是具有圓板部(27a)及卡合突起(27b),與操作桿臂朝軸方向可相對移動地裝設在手把軸的合成樹脂製的構件。圓板部,是具有卡合於非圓形部的第2非圓形孔(27c)。卡合突起,是從第2非圓形孔的周圍朝向第1非圓形孔突出,具有:卡合於非圓形部的內側面(27d)、及與第1非圓形孔卡合且形成有先端較細的第1錐面(27f)的外側面(27e)。9...操作桿臂安裝構造17a...轂部24...手把軸24a...母螺紋部24b...非圓形部24c...第1環狀突起24g...第2公螺紋部24h...第2環狀突起25...操作桿臂25a...固定部25c...第1非圓形孔25d...圓形孔25f...第4線分25g...第2錐面25h...卡合凹部27...墊圈構件27a...圓板部27b...卡合突起27c...第2非圓形孔27d...內側面27e...外側面27f...第1錐面28...軸翼構件28e...環狀溝28f...三角形溝28g...矩形溝29...彈簧構件35...固定螺栓35a...頭部36...間隔片構件36a...錐面
