A method for controlling the engagement and/or disengagement of a parking lock of a transmission of a vehicle, in particular of a motor vehicle

A method of operating a vehicle is provided. The vehicle includes: an engine; a throttle operator moveable by a driver; a throttle valve regulating airflow to the engine; a continuously variable transmission (CVT) operatively connected to the engine; at least one ground engaging member including at least one of: a wheel and a track; a piston operatively connected to a driving pulley of the CVT for applying a piston force to the driving pulley when actuated and thereby changing an effective diameter of the driving pulley; and a control unit for controlling actuation of the piston and the piston force. The method includes: determining a driven pulley speed of a driven pulley of the CVT; detecting an uphill stand condition indicative of the vehicle being stopped on an uphill; responsive to the detection of the uphill stand condition, controlling the piston force based on the driven pulley speed.

A driving assistance system for a work vehicle may comprise a service brake configured to decelerate the work vehicle upon actuation of the service brake, a parking brake and a transmission including a clutch. A controller may be configured to disengage the clutch when the work vehicle speed is less than a speed threshold and when the service brake is actuated, whereby the work vehicle is brought to a stop.

Methods and systems for a hydromechanical transmission in a vehicle are provided herein. In one example, the transmission system includes a hydrostatic assembly with a hydraulic pump in fluidic communication with a hydraulic motor. The transmission system further includes a controller configured to selectively transition between a torque control mode and a speed control mode of the hydrostatic assembly while the vehicle is on a slope.

A method of operating a vehicle is provided. The vehicle includes: an engine; a throttle operator moveable by a driver; a throttle valve regulating airflow to the engine; a continuously variable transmission (CVT) operatively connected to the engine; at least one ground engaging member including at least one of: a wheel and a track; a piston operatively connected to a driving pulley of the CVT for applying a piston force to the driving pulley when actuated and thereby changing an effective diameter of the driving pulley; and a control unit for controlling actuation of the piston and the piston force. The method includes: determining a driven pulley speed of a driven pulley of the CVT; detecting an uphill stand condition indicative of the vehicle being stopped on an uphill; responsive to the detection of the uphill stand condition, controlling the piston force based on the driven pulley speed.

A road machine includes a travel switch to cause the road machine to start traveling, a hydrostatic transmission including a traveling hydraulic pump and a traveling hydraulic motor, a pump regulator to control the discharge quantity of the traveling hydraulic pump; and a controller to control the pump regulator using a pump command current. The pump regulator increases the discharge quantity of the traveling hydraulic pump as the pump command current increases, and the controller increases the pump command current to a predetermined value smaller than a maximum current value in response to the travel switch being turned ON. Alternatively, the pump regulator increases the discharge quantity of the traveling hydraulic pump as the pump command current decreases, and the controller decreases the pump command current to a predetermined value greater than a minimum current value in response to the travel switch being turned ON.

Systems and methods for performing a garage shift of an automatic transmission of a vehicle comprise maintaining a clutch at a first holding pressure while the transmission is in a neutral gear and a brake input signal satisfies a threshold and maintaining the clutch at a lower second holding pressure while the transmission is in the neutral gear and the brake input signal satisfies the threshold to mitigate or eliminate causing drive torque to be transferred from a torque generating system of the vehicle to its driveline via the transmission. When the brake input signal satisfies the threshold and a shift from the neutral gear to a non-neutral gear is requested, the garage shift is then executed.

Systems and methods for performing a garage shift of an automatic transmission of a vehicle comprise maintaining a clutch at a first holding pressure while the transmission is in a neutral gear and a brake input signal satisfies a threshold and maintaining the clutch at a lower second holding pressure while the transmission is in the neutral gear and the brake input signal satisfies the threshold to mitigate or eliminate causing drive torque to be transferred from a torque generating system of the vehicle to its driveline via the transmission. When the brake input signal satisfies the threshold and a shift from the neutral gear to a non-neutral gear is requested, the garage shift is then executed.

A method of operating a vehicle having an engine, a throttle valve and a throttle operator. A continuously variable transmission operatively connected to the engine has a driving pulley, a driven pulley, and a belt operatively connecting the driving and driven pulleys. A ground engaging member is operatively connected to the driven pulley. A piston is operatively connected to the driving pulley for applying a piston force thereto and thereby changing an effective diameter of the driving pulley. A control unit controls actuation of the piston and the piston force. The method includes detecting a stall condition indicative of the vehicle being stalled, and, responsive to the detection, setting the piston force to be zero.

A method of operating a vehicle having an engine, a throttle valve and a throttle operator. A continuously variable transmission operatively connected to the engine has a driving pulley, a driven pulley, and a belt operatively connecting therebetween. A ground engaging member is operatively connected to the driven pulley. A piston is operatively connected to the driving pulley for applying a piston force thereto and thereby changing an effective diameter of the driving pulley. A control unit controls actuation of the piston and the piston force. The method includes determining at least one of the throttle operator and throttle valve position, detecting a parking/drive away condition indicative of one of a parking operation and a drive-away operation of the vehicle, and, responsive to the detection, actuating the piston and controlling the piston force based on the at least one of the throttle operator position and the throttle valve position.