A power transmission control device acquires rotation speed information of an idle gear corresponding to a target engagement member and rotation speed information of a sleeve corresponding to an engagement member, sets one rotation speed changeable by a power source as a synchronization side rotation speed, sets the other rotation speed as a target synchronization side rotation speed, allows a differential rotation between the synchronization side rotation speed and the target synchronization side rotation speed to match a predetermined differential rotation by changing the synchronization side rotation speed using the power source after a power transmission releasing state is selected due to a gear changing request, performs an engagement operation, inverts a sign of the predetermined differential rotation, and switches to the power transmission state while allowing the differential rotation to match the predetermined differential rotation of which the sign is inverted.

A method teaches a control function, preferably a characteristic curve, of a hydrostatic motor of a traction drive of a work machine when in drive mode. The traction drive is provided with the hydrostatic motor and a hydrostatic pump, which is hydraulically connected to the hydrostatic motor. The method includes setting a pivot angle of the hydrostatic motor while taking into account a desired velocity of the work machine when in the drive mode, and checking whether predefined conditions are met. If the predefined conditions are met and a current velocity differs from the desired velocity, the method includes correcting the control function of the hydrostatic motor by taking into account a difference between the desired velocity and the current velocity. At least one value of the corrected control function of the hydrostatic motor is taught during the correcting.

A working vehicle includes: a vehicle body provided with a traveling device; a hydraulic pump including a swashplate configured to change an output of the hydraulic pump according to a swashplate angle; a traveling motor including an output shaft having a rotation speed variable according to the output of the hydraulic pump and capable of transmitting power of the output shaft to the traveling device; an angle detector configured to detect the swashplate angle that is an angle of the swashplate; and a swashplate control unit configured to control the swashplate angle on the basis of control information relating to control of the swashplate angle and an actual swashplate angle that is the swashplate angle detected by the angle detector.

A method is for calibrating a pivot angle sensor of a hydraulic machine of a propulsion or working machine. A control device is configured to operationally control the hydraulic machine. The control device is also configured to process a sensor signal from the pivot angle sensor. The pivot angle sensor is calibrated, preferably in an automated manner, via the control device.

A continuously variable transmission, a vehicular powertrain that includes a continuously variable transmission and a method of limiting belt slippage in a continuously variable transmission in a vehicle. The continuously variable transmission includes a pulley assembly, shafts, a clutch and hydraulic system. The hydraulic system is cooperative with both the clutch and the pulley assembly so that hydraulic pressures and associated clamping forces sent to both allow the clutch to preferentially absorb any driving load coming from the axle and wheels that is in excess of the normal load experienced at the continuously variable transmission. This in turn means that any additional load that would ordinarily cause slippage in the belt is instead experienced by the clutch. By providing such a clutch, the pump of the hydraulic system does not need to be oversized in order to provide excess clamping force, as any excess load experienced by the shaft that is coupled to the wheels of the vehicle will be taken up by slippage in the clutch so that slippage-related wear to the belt is avoided.

A transmission arrangement for a travel drive, in particular a mobile machine, includes a first hydraulic machine configured to be coupled to a drive machine, and a second hydraulic machine having an adjustable second expulsion volume, the second hydraulic machine configured to be connected fluidically to the first hydraulic machine via a first working line and a second working line of the transmission arrangement. The second hydraulic machine configured to be coupled or is coupled to a manual transmission of the transmission arrangement. The manual transmission has at least two transmission stages, and coupling of the second hydraulic machine to the manual transmission has the result that a torque can be transmitted. The transmission arrangement further includes a control apparatus configured to reduce to zero or to nearly zero the second expulsion volume at least during a changeover from one transmission stage to another transmission stage of the manual transmission.

A power transmission control device acquires rotation speed information of an idle gear corresponding to a target engagement member and rotation speed information of a sleeve corresponding to an engagement member, sets one rotation speed changeable by a power source as a synchronization side rotation speed, sets the other rotation speed as a target synchronization side rotation speed, allows a differential rotation between the synchronization side rotation speed and the target synchronization side rotation speed to match a predetermined differential rotation by changing the synchronization side rotation speed using the power source after a power transmission releasing state is selected due to a gear changing request, performs an engagement operation, inverts a sign of the predetermined differential rotation, and switches to the power transmission state while allowing the differential rotation to match the predetermined differential rotation of which the sign is inverted.

A method for operating a hydrostatic transmission of a drive train of a motor vehicle. An automatic creep function of the motor vehicle is made possible by the hydrostatic transmission. in order to be able to realize the creep function in a reliable manner, a current value of a first parameter that is independent of a pedal position of an accelerator and a current value of a second parameter that is dependent on the pedal position are compared to each another. The creep function is then activated as long as the current value of the first parameter is greater than the current value of the second parameter. In the context of the creep function, the current value of the first parameter is used to determine a current value of a target delivery quantity of a hydrostatic machine of the transmission operated as a pump.

A working vehicle includes: a vehicle body provided with a traveling device; a hydraulic pump including a swashplate configured to change an output of the hydraulic pump according to a swashplate angle; a traveling motor including an output shaft having a rotation speed variable according to the output of the hydraulic pump and capable of transmitting power of the output shaft to the traveling device; an angle detector configured to detect the swashplate angle that is an angle of the swashplate; and a swashplate control unit configured to control the swashplate angle on the basis of control information relating to control of the swashplate angle and an actual swashplate angle that is the swashplate angle detected by the angle detector.

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.