A hydrostatic traction drive for a mobile working machine includes a first hydraulic machine coupled to a drive machine, a second hydraulic machine arranged with the first hydraulic machine in a hydraulic circuit and coupled to an output, and an electronic control device. A characteristic diagram of a setpoint driving behavior of the mobile working machine is stored in the electronic control device and is parameterized at least in accordance with at least one driving request.

A hydrostatic traction drive for a mobile working machine includes a first hydraulic machine coupled to a drive machine, a second hydraulic machine arranged with the first hydraulic machine in a hydraulic circuit and coupled to an output, and an electronic control device. A characteristic diagram of a setpoint driving behavior of the mobile working machine is stored in the electronic control device and is parameterized at least in accordance with at least one driving request.

A device for controlling a gear ratio of a hydrostatic mechanical power-split transmission comprises an input switch (1) which, when rotated, produces a particular transmission characteristic and, at the same time, limits the maximum pressure. The selected position of the input switch (1) selects a particular maximum pressure curve from a large number of stored maximum pressure curves.

A hydrostatic transmission for a working machine having a frame, an engine on the frame, and at least one wheel driven by the hydrostatic transmission is disclosed. The hydrostatic transmission includes a housing, a hydraulic pump, the hydraulic pump driven by an output shaft from the engine, a hydraulic motor for driving an output shaft connected to the at least one wheel, a first fluid line fillable with hydraulic fluid to be maintained under a first pressure, a second fluid line fillable with hydraulic fluid to be maintained under a second pressure, a first check valve for allowing hydraulic fluid to enter the first fluid line, a second check valve for allowing hydraulic fluid to enter the second fluid line, and an entrained air deflector for preventing hydraulic fluid entrained with air from entering the first check valve and the second check valve.

Provided is a transmission control system that enables more precise control of the transmission ratio. This transmission control system is provided with a motor, an actuator, a transmission, a position sensor, a current sensor, and a control unit. The control unit includes: a drive unit that drives the motor while the vehicle is stopped; and a first estimation unit that estimates the initial transmission ratio, which indicates the transmission ratio when the ignition switch is turned on, on the basis of a rotation position detected by the position sensor, a load current detected by the current sensor, and a characteristic curve over a period during which the drive unit is operating.

A hydrostatic transmission for a working machine having a frame, an engine on the frame, and at least one wheel driven by the hydrostatic transmission is disclosed. The hydrostatic transmission includes a housing, a hydraulic pump, the hydraulic pump driven by an output shaft from the engine, a hydraulic motor for driving an output shaft connected to the at least one wheel, a first fluid line fillable with hydraulic fluid to be maintained under a first pressure, a second fluid line fillable with hydraulic fluid to be maintained under a second pressure, a first check valve for allowing hydraulic fluid to enter the first fluid line, a second check valve for allowing hydraulic fluid to enter the second fluid line, and an entrained air deflector for preventing hydraulic fluid entrained with air from entering the first check valve and the second check valve.

Provided is a transmission control system that enables more precise control of the transmission ratio. This transmission control system is provided with a motor, an actuator, a transmission, a position sensor, a current sensor, and a control unit. The control unit includes: a drive unit that drives the motor while the vehicle is stopped; and a first estimation unit that estimates the initial transmission ratio, which indicates the transmission ratio when the ignition switch is turned on, on the basis of a rotation position detected by the position sensor, a load current detected by the current sensor, and a characteristic curve over a period during which the drive unit is operating.

A device for controlling a gear ratio of a hydrostatic mechanical power-split transmission comprises an input switch (1) which, when rotated, produces a particular transmission characteristic and, at the same time, limits the maximum pressure. The selected position of the input switch (1) selects a particular maximum pressure curve from a large number of stored maximum pressure curves.

A hydrostatic transmission control system includes a controller that monitors inputs for shifting a transmission of a tractor to a different range gear; determines if an engine on the tractor is operating in a desired and acceptable shift range based on a sensed speed and a load of the engine, and determines if a hydrostatic transmission on the tractor is operating in a desired and acceptable shift range based on a sensed load and a speed of the hydrostatic transmission. If the controller determines the engine and the hydrostatic transmission are operating in the desired and acceptable shift range, the controller commands an oncoming clutch to ramp up and an off going clutch to ramp down, and synchronizes speeds of the engine and the hydrostatic transmission.