PROBLEM TO BE SOLVED: To enable easy elimination of the effects of dust caused by the soil of pot seedlings and moisture.SOLUTION: This sensor 2 for the lack of seedling in a seedling transplanter, equipped with a seedling box-conveying device 3 for conveying the seedling box N arranged with many pot seedling chambers Na along a seedling box-conveying passage R and a seedling box-pushing out device 4 for pushing out a prescribed number of pot seedlings P from the seedling box N at a prescribed pushing out position on the seedling box-conveying passage R is provided by equipping a pushing out sensor 15 for detecting the pushing out action of the pot seedling P at the seedling-pushing out device 4, and a seedling box sensor 16 for detecting the movement of the seedling box N conveyed by the seedling box-conveying device 3, and is constituted so that an alarm is issued in the case that the movement of the seedling box N of the prescribed number is not detected by the seedling box sensor 16, while the pushing out sensor 15 detects the prescribed number of pushing out actions.COPYRIGHT: (C)2010,JPO&INPIT【課題】 ポット苗の土等による埃や湿気の影響を排除しやすくする。【解決手段】 本発明の欠株センサ2は、多数のポット苗室Naが配設された苗箱Nを苗箱搬送経路Rに沿って搬送する苗箱搬送装置3と、該苗箱搬送経路R上の所定の押出位置で苗箱Nから所定数のポット苗Pを押し出す苗押出装置4とを備えた苗移植機におけるものであり、苗押出装置4におけるポット苗Pの押出動作を検出する押出センサ15と、苗箱搬送装置3により搬送されている苗箱Nの移動を検出する苗箱センサ16とを備え、押出センサ15が所定回数の押出動作を検出する間に、苗箱センサ16が所定量の苗箱Nの移動を検出しないときは警報を発するように構成されている。【選択図】 図2
