A method of starting or holding a mobile vehicle and, in particular, a working machine. The method determines whether the vehicle is rolling backward on an inclined surface and, as a function of that knowledge, the rotational speed of the drive engine is increased, or a downshift by one gear is carried out in the transmission.

An object of the present invention is to provide a vehicle parking lock system that realizes a parking lock with a positive user perception, and enables energy and cost reductions without complex control and with a simple configuration. The object is achieved by a selectable clutch configured to be switchable between four operating modes and provided to one of an input shaft, an output shaft, and an intermediate shaft of a transmission. The operating mode of the selectable clutch is controlled based on detection signals of a plurality of sensors to prevent an unintended movement of the vehicle when the vehicle is stationary.

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.

The SBW-CU that constitutes the shift control device, in the case of selection information for selecting a shift range other than the P range being output by the selection position determination unit when the shift range of the automatic transmission is the P range, maintains the P range without switching the shift range of the automatic transmission in the case of the engine being stopped, and the gradient of the road surface being equal to or greater than a predetermined threshold, and switches the shift range of the automatic transmission based on selection information in the case of the engine not being stopped, or in the case of the road surface gradient being less than the aforementioned predetermined threshold.

A hill stop control method includes: when it is determined that a vehicle is in a park brake state, determining, by acquiring the current parameter of the vehicle, whether the vehicle is in a working condition of being prone to sliding; and when it is determined that the vehicle is in a working condition of being prone to sliding, controlling a mode switch of a transfer case to switch the current drive mode to a high-speed four-wheel drive mode having a stronger brake force or a low-speed drive mode. In this way, the automatic switching of a drive mode is realized without changing a brake system; and when stopped on a hill, friction forces between tires and the ground are increased, thereby effectively reducing the risk of sliding down a hill.

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.

A method of operating a vehicle having an engine, a throttle valve and a throttle operator. A continuously variable transmission is operatively connected to the engine and has a driving pulley, a driven pulley, and a belt operatively connecting therebetween. At least one ground engaging member is operatively connected to the driven pulley and includes at least one of a wheel and a track. A piston is operatively connected to the driving pulley for applying a piston force to the driving pulley when actuated 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 an engine speed, and controlling the piston force based on the engine speed.

A control method for preventing backward slipping of a vehicle includes a range detection step in which a controller detects a range position of a shift lever, a gradient comparison step in which the controller compares a gradient of a road with a predetermined reference gradient when it is determined that the position of the shift lever is the D range, a stop state check step where the controller checks a brake and a driving state of the vehicle when it is determined at the gradient comparison step that the gradient of the road is equal to or greater than the reference gradient, and an inter-lock implementation step in which the controller engages multiple gears on an identical shaft when it is determined at the stop state check step that the brake is on and the vehicle has stopped.

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.

A controller is provided to, in response to a speed of the vehicle exceeding an allowable speed based on a measured grade while the vehicle is running and in neutral or park, actuating a vehicle holding mechanism to stop the vehicle.