| 主权项 |
1. A work vehicle, comprising:
an engine; a hydraulic pump configured to be driven by the engine; a work implement configured to be driven by a hydraulic oil discharged from the hydraulic pump; a travelling apparatus configured to be driven by the engine; a power transmission configured to transmit a driving force from the engine to the travelling apparatus; a controller configured to control the power transmission; and an operating device configured to be operated by an operator, the power transmission including
an input shaft,an output shaft,a gear mechanism having a planetary gear mechanism, the gear mechanism being configured to transmit a rotation of the input shaft to the output shaft,a motor connected to a rotary element of the planetary gear mechanism,a first clutch for switching a transmission path for the driving force in the power transmission into a first mode, anda second clutch for switching the transmission path for the driving force in the power transmission into a second mode,when the transmission path is set in the first mode, the first clutch being configured to be engaged and the second clutch being configured to be disengaged,when the transmission path is set in the second mode, the second clutch being configured to be engaged and the first clutch being configured to be disengaged,in the power transmission, a speed ratio of the output shaft to the input shaft varying when a rotational speed of the motor varies,when a speed ratio parameter corresponding to the speed ratio is a predetermined mode switching threshold, a rotational speed ratio of the motor to the input shaft in the first mode and a rotational speed ratio of the motor to the input shaft in the second mode becoming equal, and the controller including
a clutch controlling unit configured to switch the transmission path from one to the other of the first and second modes when the speed ratio parameter reaches the mode switching threshold,a trigger operation detecting unit configured to detect whether or not a predetermined operation is performed by the operator, anda timer configured to measure a period of time elapsed from a first point of time at which the transmission path is switched into the other mode, the clutch controlling unit being configured to keep setting the transmission path in the other mode even when the speed ratio parameter again reaches the mode switching threshold until a switching prohibition period expires as long as the elapsed period of time is within the switching prohibition period, the switching prohibition period having a predetermined initial value, and the trigger operation detecting unit being configured to make the switching prohibition period expire when detecting the predetermined operation in the switching prohibition period. |
