PROBLEM TO BE SOLVED: To simultaneously attain prevention of deep planting in rice planting operation at low-speed traveling and prevention of seedling floating in rice transplanting operation at high-speed traveling, in a riding type rice transplanter equipped with a hydraulic cylinder 43 for lifting and lowering a seedling-planting apparatus 3 attached to a traveling machine body which loads an engine 7 and a traveling speed change transmission 8 and its hydraulic changeover valve 49 and making a changeover operation member 52 of the hydraulic changeover valve cooperate with a float 47b of the seedling planting apparatus so as to changeover the hydraulic changeover valve to a rise of the seedling planting apparatus by at least rise movement of the float.SOLUTION: When speed change operation of a traveling speed change operation means 12 of a traveling speed change transmission is carried out so as to increase traveling speed, the traveling speed change operation means is made to cooperate with a changeover operation member 52 so as to prevent changeover operation from rising of a seedling transplantation apparatus accompanied by raising movement of a float in the changeover operation member.COPYRIGHT: (C)2009,JPO&INPIT【課題】エンジン7及び走行変速ミッション8を搭載の走行機体に装着した苗植え装置3を昇降動する油圧シリンダ43,その油圧切換弁49を備え,前記油圧切換弁の切換え作動部材52に,前記苗植え装置のフロート47bを,少なくとも,当該フロートの上昇動にて前記油圧切換弁を前記苗植え装置の上昇に切り換え作動するように連携して成る乗用型田植機において,低速走行での田植え作業の際の深植え防止と,高速走行での田植え作業の浮苗防止とを同時に達成する。【解決手段】前記切換え作動部材52に,前記走行変速ミッションの走行変速操作手段12を,当該走行変速操作手段を走行速度増に変速操作したときに,前記切換え作動部材における前記フロートの上昇動に伴う前記苗植え装置の上昇への切り換え作動を妨げるように連携する。【選択図】 図8
