PROBLEM TO BE SOLVED: To adjust the height of culture soil with the gradient of a ridging plate and to simultaneously achieve the expansion/contraction adjustment and angle adjustment of extended auxiliary blade plates.SOLUTION: A curved part with a length to connect a ridging plate body to be vertically displaceable along a curved surface is formed on the tip side of a shank, and the curved part of the shank and a center ridgeline part of the ridging plate body abutting on the curved part, are connected by selecting a plurality of upper and lower mounting holes. A plurality of longitudinal holes are formed in a ridging plate surface and associated with laterally long holes formed in the axial direction of the extended auxiliary blade plates, to adjust the expansion/contraction length and angle of the extended auxiliary blade plates. An excavation blade of different shape or the same shape can be replaceably attached to and detached from the tip of the ridging plate body. The axial edges of the extended auxiliary blade plates are formed in an asymmetrical shape with respect to the axis, and the right and left extended auxiliary blade plates can be replaced and reversely connected.COPYRIGHT: (C)2013,JPO&INPIT【課題】培土板の勾配で培土の高低を調整し、且つ、延長補助翼板の伸縮調整と角度調整を同時に達成させる。【解決手段】シャンク先端側に、培土板本体が湾曲面に沿って上下変位可能に結合させる長さの湾曲部を形成し、シャンクの湾曲部と、この湾曲部に当接される培土板本体の中央稜線部とを、上下複数取付け孔選択して結合する。培土板面に複数の縦長孔を形成し、延長補助翼板の軸方向に形成した横長孔に対応させて延長補助翼板の伸縮長さ及び角度を調節できるようにした。培土板本体の先端に、異形又は同形の掘削刃を交換可能に脱着できるようにした。前記延長補助翼板の軸方向縁辺を中心軸線に対して非対称形に形成し、左右延長補助翼板を入れ替えて反転結合できるようにした。【選択図】図2
