PROBLEM TO BE SOLVED: To provide a lawn mower which is surely operable while reducing the risk of overload state to a driving unit at the time of starting blade rotation.SOLUTION: A lawn mower include a blade 30 that rotates by a motor 15 and moves on a substantially plane cutting surface with respect to the ground, in which the blade is placed between front and rear wheels 2, 3. The blades are connected to the motor via movable means 17 which is movable vertically, in which the blade is moved upward away from the ground at the time of starting a power source or rotating at a low speed, and is moved downward while coming closer to the ground at the time of rotating at a high speed. The movable means includes a sleeve 17 which is provided to a drive shaft 16 and is relatively movable in an axis direction, and elastic means which energizes the sleeve and the drive shaft in the axis direction. A rotational blade is mounted to the sleeve. An air-sending blade portion 33 is formed on the rotational blade which is lowered at the time of high-speed rotation by upward wind from the rotation.COPYRIGHT: (C)2015,JPO&INPIT【課題】ブレードの回転開始時に駆動部への過負荷状態となる恐れを低減させて、確実に起動できるようにした芝刈機の提供。【解決手段】モータ15により回転し地面に対して略平行な切削面にて移動するブレード30を有し、前後の車輪2、3の間にブレードが配置される芝刈機において、ブレードを上下方向に移動可能な可動手段17を介してモータに接続し、動力源の起動時又は低速回転時にはブレードを地面から離れた位置に上昇させ、高速回転時にはブレードが地面に近づくように下降させる。可動手段は、駆動軸16に設けられ軸方向に相対移動可能なスリーブ17と、スリーブと駆動軸を軸方向に付勢する弾性手段を含んで構成され、回転刃はスリーブに取り付けられる。回転刃には送風用の羽根部33が形成され、回転時の上向きの風により高速回転時に回転刃を下降させる。【選択図】図1
