PROBLEM TO BE SOLVED: To provide a soil supply device of a seeding machine for a nursery box in which the tension condition of a soil feed belt can easily be adjusted.SOLUTION: A soil supply device to nursery box in a seeding machine for the nursery box comprises a tension mechanism for adjusting the tension condition of a soil feed belt. The tension mechanism is configured by projecting a screw pipe in the longitudinal direction side from an insertion hole of a support plate part provided in a frame side plate, providing a screw shaft for performing forward/backward movement in the screw pipe, and providing a bearing of the driven axis in the end of the screw shaft. The screw pipe and the screw shaft are moved at the same time, and the position of the driven axis can be switched between a tension position and a relaxation position.SELECTED DRAWING: Figure 3【課題】土繰出しベルトの張り具合の調整を容易にできる育苗箱用播種機の土供給装置を提供する。【解決手段】育苗箱用播種機における育苗箱への土供給装置において、土繰出しベルトの張り具合を調整するテンション機構を具備し、前記テンション機構は、フレーム側板に設けた支持板部の挿通孔より、前後方向側に螺子パイプを突出させ、該螺子パイプ内を前後移動する螺子軸を設け、該螺子軸の端部に該従動軸の軸受を設けた構成とし、該螺子パイプと螺子軸が同時に移動されて、該従動軸の位置を緊張位置と弛緩位置に切替え可能とした。【選択図】図３
