A work vehicle includes an engine, a traveling pump driven by the engine, a hydraulic circuit connected to the traveling pump, a traveling motor connected to the traveling pump via the hydraulic circuit, a rotational speed sensor configured to output a signal indicative of engine speed a hydraulic pressure sensor configured to output a signal indicative of hydraulic pressure of the hydraulic circuit, a controller. The controller receives the signals from the rotational speed sensor and the hydraulic pressure sensor. The controller determines whether the engine is in an over-rotation state based on engine speed. The controller determines an upper limit value of a displacement of the traveling pump based on hydraulic pressure of the hydraulic circuit. The controller limits the displacement of the traveling pump to the upper limit value or less upon determining that the engine is in the over-rotation state.

A method to control a road vehicle for the execution of a multiple downshift in a drivetrain provided with a servo-assisted transmission; the control method comprises the steps of: detecting a condition of slowing down of the road vehicle and, simultaneously, detecting a driver's request for a multiple downshift; carrying out, in succession, a plurality of downshifts while the road vehicle is slowing down and in an autonomous manner regardless of further interventions of the driver; determining a duration of a shift time interval; and carrying out each downshift following a first downshift when said shift time interval has exactly elapsed since the previous downshift.

A method to control a road vehicle for the execution of a multiple downshift in a drivetrain provided with a servo-assisted transmission; the control method comprises the steps of: detecting a condition of slowing down of the road vehicle and, simultaneously, detecting a driver's request for a multiple downshift; carrying out, in succession, a plurality of downshifts while the road vehicle is slowing down and in an autonomous manner regardless of further interventions of the driver; determining a duration of a shift time interval; and carrying out each downshift following a first downshift when said shift time interval has exactly elapsed since the previous downshift.

A method to automatically control a drivetrain provided with a servo-assisted transmission; the method comprises the steps of: measuring a rotation speed of the internal combustion engine; carrying out a shift to a lower gear in an autonomous manner and independently of an intervention of a driver, when the rotation speed of the internal combustion engine reaches a lower threshold; carrying out a shift to a higher gear in an autonomous manner and independently of an intervention of the driver, when the rotation speed of the internal combustion engine reaches an upper threshold; detecting a release of an accelerator pedal in a first instant; waiting, starting from the first instant, a time interval until a second instant, which is subsequent to the first instant; and increasing a value of the lower threshold starting from the instant until a following pressing of the accelerator pedal.

A method to automatically control a drivetrain provided with a servo-assisted transmission; the method comprises the steps of: measuring a rotation speed of the internal combustion engine; carrying out a shift to a lower gear in an autonomous manner and independently of an intervention of a driver, when the rotation speed of the internal combustion engine reaches a lower threshold; carrying out a shift to a higher gear in an autonomous manner and independently of an intervention of the driver, when the rotation speed of the internal combustion engine reaches an upper threshold; detecting a release of an accelerator pedal in a first instant; waiting, starting from the first instant, a time interval until a second instant, which is subsequent to the first instant; and increasing a value of the lower threshold starting from the instant until a following pressing of the accelerator pedal.

This vehicle control devices provided with: a travel segment determination unit 15 which determines a next travel segment, forwards in the travel direction of the vehicle, which has a different road slope from the current travel segment where the vehicle is currently traveling; a next gear stage selection unit 16 which, on the basis of the road slope of the next travel segment, selects a next gear stage, which will be the gear stage of the vehicle in the next travel segment; and a shift control unit 17 which upshifts to the next gear stage in the current travel segment in the case that the travel resistance in the next travel segment is less than the travel resistance of the current travel segment, the value obtained by subtracting the travel resistance of the vehicle in the current travel segment from the drive force at the current speed of the vehicle in the next gear stage is less than a first prescribed value, and the value obtained by subtracting the travel resistance of the vehicle in the next travel segment from the drive force at the current vehicle speed in the next gear stage is less than a second prescribed value.

A control system operates a power train of a work vehicle. The system includes a transmission arrangement which transfers power from an engine to an output shaft of the vehicle to drive the vehicle in a first or second direction according to at least one forward or reverse modes. The arrangement includes a forward directional clutch and a reverse directional clutch, and a controller. The controller is configured to determine if one of the clutches is engaged; evaluate a speed of the engine; and provide a torque command to engage the other of the clutches to slow the speed of the engine when a shuttle shift is initiated, or when the speed of the engine exceeds a predetermined speed threshold.

An apparatus and a method for controlling shifting of a vehicle are provided. The apparatus includes a transmission configured to transmit power generated from by a motor to a vehicle wheel, and a controller configured to control an operation of the transmission. The controller is configured to enter a LURCH control mode when sensing shifting of a shift lever between a D range and an R range during driving to maintain a clutch torque in the transmission, to decrease a vehicle speed by controlling a motor speed, and to shift a gear of the vehicle by changing a motor torque when the vehicle speed reaches a threshold speed.

An apparatus and a method for controlling shifting of a vehicle are provided. The apparatus includes a transmission configured to transmit power generated from by a motor to a vehicle wheel, and a controller configured to control an operation of the transmission. The controller is configured to enter a LURCH control mode when sensing shifting of a shift lever between a D range and an R range during driving to maintain a clutch torque in the transmission, to decrease a vehicle speed by controlling a motor speed, and to shift a gear of the vehicle by changing a motor torque when the vehicle speed reaches a threshold speed.

This vehicle control devices provided with: a travel segment determination unit 15 which determines a next travel segment, forwards in the travel direction of the vehicle, which has a different road slope from the current travel segment where the vehicle is currently traveling; a next gear stage selection unit 16 which, on the basis of the road slope of the next travel segment, selects a next gear stage, which will be the gear stage of the vehicle in the next travel segment; and a shift control unit 17 which upshifts to the next gear stage in the current travel segment in the case that the travel resistance in the next travel segment is less than the travel resistance of the current travel segment, the value obtained by subtracting the travel resistance of the vehicle in the current travel segment from the drive force at the current speed of the vehicle in the next gear stage is less than a first prescribed value, and the value obtained by subtracting the travel resistance of the vehicle in the next travel segment from the drive force at the current vehicle speed in the next gear stage is less than a second prescribed value.