| 摘要 |
PURPOSE: To avoid a state to drop seedlings from a planting claw by setting and changing a minimum speed position of a stepless speed change gear to the constant speed side at the time of detecting a road travelling state and setting and changing the minimum speed position to a high speed side at the time of detecting a rice pad travelling state. CONSTITUTION: When an auxiliary speed change lever 13 is operated at a high speed position H, a control device 1 judges it as in a road travelling state, and a first low speed position F1 on the forwarding side and a first low speed position R1 on the retreating side are set about a stationary hydraulic speed changer 5. At this time, when a main speed change lever 10 is operated at the forwarding high speed side beyond the low speed position F1, a trunnion shaft 6 (swash plate) is operated on the high speed side by a cylinder 7 with an angle A1 corresponding to the position F1 as a starting point. In the meantime, when the auxiliary lever 13 is operated at a low speed position L, it is judged as in a rice pad travelling state, a second low speed position F2 on the forwarding side which is a higher speed side than each of the low speed positions F1, R1 and a low speed position R2 on the high speed side are set. |
