Abstract: A speed change system for work vehicle having a continuously variable transmission device selects a first change gear ratio which is set larger than a smallest change gear ratio, when an engine rotational speed is a first set rotational speed which is set equal or close to an idling rotational speed of an engine; retains the change gear ratio of the continuously variable transmission device at the smallest change gear ratio, when the engine rotational speed is equal to or above a second set rotational speed set on a high-speed side relative to the first set rotational speed; and makes the change gear ratio of the continuously variable transmission device larger between the first change gear ratio and the smallest change gear ratio, as the engine rotational speed at that moment becomes lower, when the engine rotational speed is between the first and second set rotational speeds.

Abstract: Controlling means of a work vehicle includes, as speed change output setting data indicative of relationship between operational positions of the operational pedal and outputs from a stepless speed change device, first data for setting a deceleration completion position of the operational pedal where the output from the stepless speed change device is zero to provide a larger operational amount of the operational pedal from a stepping release position and second data for setting the deceleration completion position to provide a smaller operational amount of the operational pedal from the stepping release position.

Abstract: A speed changing control system for a vehicle including a speed changing device for speed changing a rotational power from an engine and outputting the resultant power, a speed changing control unit for setting a speed change ratio of the speed changing device, and an engine control unit for setting an engine rotational speed of the engine. Based on an operational instruction in response to a driver's operation, a rotational speed reducing instruction is given to the engine control unit for reducing an engine rotational speed set by the engine control unit by a predetermined amount. Also, a speed changing ratio changing instruction is given to the engine control unit for requesting, to a speed changing control unit, a change of the speed change ratio for compensating for the reduction in the engine rotational speed by the rotational speed reducing instruction so as to maintain the vehicle speed.

Abstract: A transmission device for a work vehicle, comprising a travel drive system for transmitting engine power to a travel device; an implement drive system for transmitting engine power to an external power take-off shaft; braking operation tools for a braking operation; a stop operation mechanism provided to the travel drive system and capable of interrupting the transmission of power to the travel device; and a hydraulically operated PTO clutch for interrupting the transmission of power to the external power take-off shaft, the PTO shaft being provided to the implement drive system; wherein the stop operation mechanism and the PTO clutch are linked with the braking operation tools so that the stop operation mechanism is operated to a power transmission stopping position and the PTO clutch is disengaged along with a pressing operation of the braking operation tools, and the PTO clutch is engaged along with a press-releasing operation of the braking operation tools; and an operation timing is set so that the PT

Abstract: A speed change system for work vehicle having a continuously variable transmission device selects a first change gear ratio which is set larger than a smallest change gear ratio, when an engine rotational speed is a first set rotational speed which is set equal or close to an idling rotational speed of an engine; retains the change gear ratio of the continuously variable transmission device at the smallest change gear ratio, when the engine rotational speed is equal to or above a second set rotational speed set on a high-speed side relative to the first set rotational speed; and makes the change gear ratio of the continuously variable transmission device larger between the first change gear ratio and the smallest change gear ratio, as the engine rotational speed at that moment becomes lower, when the engine rotational speed is between the first and second set rotational speeds.

Abstract: A PTO control system for allowing selection between an independent PTO mode and an interlock PTO mode, comprising a mode-switch command input device 11 for giving an instruction on selection between the independent PTO mode and the interlock PTO mode, a PTO setting device 12 having an engaging position for producing an engaging command and a disengaging position for producing a disengaging command of the PTO clutch, and a PTO control unit for controlling a PTO clutch in response to a pedal operational position of a brake pedal, a mode selected by the mode-switch command input device, and a position selected by the PTO setting device. PTO mode switch implementation processing is suspended when the PTO transmission system is in a power transmittable state, while the PTO mode switch implementation processing is permitted when the PTO transmission system is in the power non-transmittable state.

Abstract: A transmission device for a work vehicle, comprising a travel drive system for transmitting engine power to a travel device; an implement drive system for transmitting engine power to an external power take-off shaft; braking operation tools for a braking operation; a stop operation mechanism provided to the travel drive system and capable of interrupting the transmission of power to the travel device; and a hydraulically operated PTO clutch for interrupting the transmission of power to the external power take-off shaft, the PTO shaft being provided to the implement drive system; wherein the stop operation mechanism and the PTO clutch are linked with the braking operation tools so that the stop operation mechanism is operated to a power transmission stopping position and the PTO clutch is disengaged along with a pressing operation of the braking operation tools, and the PTO clutch is engaged along with a press-releasing operation of the braking operation tools; and an operation timing is set so that the PT