PROBLEM TO BE SOLVED: To provide a rice transplanter enabling seedling planting between large-spaced roots and small-spaced roots while avoiding occurrence of the seedling planting defects and/or driving defects of a seedling planting mechanism.SOLUTION: The rice transplanter has the following construction: A seedling planting driving mechanism D is equipped with a first interroot variable-speed section 60 having multiple gear pairs 63, 64 and 65 realizing multiple-tier variable-speed transmission modes of different variable-speed ratios and a second interroot variable-speed section 70 having a pair of eccentric gears 75 realizing an irregular-speed transmission mode and a pair of gears 74 realizing a variable-speed/regular-speed transmission mode. In this rice transplanter, the seedling planting driving mechanism D works as follows: when the second interroot variable-speed section 70 is switched to the irregular-speed transmission mode, a large interroot space with a magnitude corresponding to the variable-speed mode of the first interroot variable-speed section 60 is set by the pairs of gears 63, 64 and 65 and the pair of eccentric gears 75, whereas when the second interroot variable-speed section 70 is switched to the variable-speed/regular-speed transmission mode, a small interroot space with a magnitude corresponding to the variable-speed mode of the first interroot variable-speed section 60 is set by the pairs of gears 63, 64 and 65 and the pair of gears 74.COPYRIGHT: (C)2009,JPO&INPIT【課題】 苗植え付け機構の苗植え不良や駆動不良の発生を回避しながら大株間と小株間とでの苗植付けを行うことができる田植機を提供する。【解決手段】 苗植え駆動機構Dに、変速比が異なる複数段の変速伝動状態を現出する複数のギヤ対63,64,65有した第一株間変速部60を設け、不等速伝動状態を現出する偏芯ギヤ対75と、変速等速伝動状態を現出するギヤ対74とを有した第二株間変速部70を設けてある。苗植え駆動機構Dは、第二株間変速部70が不等速伝動状態に切り換えられると、第一株間変速部60のギヤ対63,64,65と第二株間変速部70の偏芯ギヤ対75とによって第一株間変速部60の変速伝動状態に対応した大きさの大株間を設定し、第二株間変速部70が変速等速伝動状態に切り換えられると、第一株間変速部60のギヤ対63,64,65と第二株間変速部70のギヤ対74とによって第一株間変速部60の変速伝動状態に対応した大きさの小株間を設定する。【選択図】 図4
