Safety structure of grain pulling chain transmission box

The utility model relates to the technical field of transmission mechanisms, in particular to a seedling pulling chain transmission case safety structure which comprises a plurality of transfer cases, each transfer case comprises a case body, the plurality of transfer cases are rotatably provided with an input main shaft, gear sleeves are nested on the outer side of the input main shaft, a gear sleeve is arranged in each transfer case, and the gear sleeves are arranged in the case bodies. A reversing box is installed in the middle of the input main shaft, a reversing gear set is arranged in the reversing box, a first transmission shaft is installed on the reversing box, the first transmission shaft is meshed with the input main shaft through the reversing gear set, the first transmission shaft is installed at the output end of the spring clutch, and a second transmission shaft is installed at the input end of the spring clutch. The input main shaft is a hexagonal shaft. The multiple transfer cases are connect