A control device for a continuously variable transmission performs transmission control so that an actual transmission control value becomes a target transmission control value. The control device includes a lead compensation unit, delay compensation unit, and a setting unit. The lead compensation unit performs lead compensation of the target transmission control value. The delay compensation unit performs delay compensation of the target transmission control value. The setting unit is configured to set as the target transmission control value a post-compensation target transmission control value for which compensation is performed by the lead compensation unit and the delay compensation unit according to at least one of an input side rotation speed of the continuously variable transmission, an input torque to a driven side rotation element of the continuously variable transmission, a transmission ratio of the continuously variable transmission, and a rate of change of the transmission ratio.

A work vehicle that includes a hydraulic system. The hydraulic system includes a hydraulic motor that generates rotational power for one or more wheels on the work vehicle. A hydraulic pump couples to the hydraulic motor. The hydraulic pump pumps hydraulic fluid to the hydraulic motor. A hydraulic shift control system controls shifting of the hydraulic system. The hydraulic shift control system includes a controller that controls a hydraulic motor volume of the hydraulic motor and a fluid volume pumped by the hydraulic pump to gradually change a speed of the work vehicle during a shift.

A method for controlling gear shifting, including: acquiring a current gear-shifting parameter of the vehicle (101); according to the current gear-shifting parameter and a preset target rotational speed, determining a gear-shifting inputted rotational speed (102); and when a rotational speed of the vehicle reaches the gear-shifting inputted rotational speed, controlling a shifting fork to start up a gear-shifting operation (103). The method for controlling gear shifting presets the target rotational speed of the gears, and, according to the current gear-shifting parameter of the vehicle that is acquired in real time and the preset target rotational speed, inversely calculates the gear-shifting inputted rotational speed, whereby the gear-shifting inputted rotational speed is an accurate gear-shifting inputted rotational speed that matches with the current condition of the vehicle. When the rotational speed of the vehicle reaches the gear-shifting inputted rotational speed, the shifting fork is controlled to start up a gear-shifting operation, which can realize the accurate gear shifting of the vehicle, which greatly improves the stability of the vehicle when a dual-clutch automatic transmission is performing gear shifting.

An ECU executes a first control when an automatic transmission has a shift range changed from an N range to a D range. In the first control, the ECU initially rotates an EOP and also sets a motor generator's rotational speed to a prescribed rotational speed. The ECU rapidly engages a Drive clutch while maintaining the motor generator's rotational speed at the prescribed rotational speed. The ECU then increases the motor generator's rotational speed to a target rotational speed set for the D range.

Methods and system are described for changing a driveline gear range from a higher gear range to a lower gear range. The driveline may include two electric machines and four clutches in a four wheel drive configuration. The methods and systems permit a driveline to change from a higher gear range to a lower gear range without stopping a vehicle.

A working vehicle includes a first hydraulic clutch connected to the first traveling shaft, a second hydraulic clutch connected to the first traveling shaft separately from the first hydraulic clutch, a first gear mechanism to transmit, to a second traveling shaft, power from the first hydraulic clutch when the first hydraulic clutch is engaged and not to transmit, to the second traveling shaft, power from the first hydraulic clutch when the first hydraulic clutch is disengaged, and a second gear mechanism to transmit, to the second traveling shaft, power from the second hydraulic clutch when the second hydraulic clutch is engaged and not to transmit, to the second traveling shaft, power from the second hydraulic clutch when the second hydraulic clutch is disengaged.

A drive train control method includes transmitting a total time period of a stroke phase and a torque phase of an upshift from a transmission control unit of an automatic transmission to an engine control unit of an engine. The method also includes closing a first shift element of the automatic transmission and opening a second shift element of the automatic transmission during the upshift. A control pressure of the first shift element increases during the torque phase relative to the control pressure of the first shift element at an end of the stroke phase. A control pressure of the second shift element decreases during the torque phase relative to the control pressure of the second shift element at the end of the stroke phase. The method further includes, based at least in part on the total time period of the stroke and torque phases, increasing an actual torque of the engine during the upshift such that the actual torque of the engine increases to a higher gear torque prior to an end of the torque phase.

An automatic transmission includes a main transmission and an auxiliary transmission. The auxiliary transmission includes an auxiliary-transmission-side planetary gear mechanism, a first clutch, and a second clutch. The auxiliary-transmission-side planetary gear mechanism is provided between a pair of main-transmission-side planetary gear mechanisms, and a part of the auxiliary-transmission-side planetary gear mechanism is located within the main transmission. The first clutch fixes rotation of a sun gear of the auxiliary-transmission-side planetary gear mechanism. The second clutch connects a ring gear of the auxiliary-transmission-side planetary gear mechanism with the sun gear.

A power system includes an engine; a sensor to determine an engine speed; and a transmission. The transmission includes an input element configured to receive the power from the engine as input torque; an output element configured to provide at least a portion the power from the engine as output torque; and a clutch arrangement to transform the input torque into output torque. The clutch arrangement includes at least one clutch selectively positionable between a fully engaged state, a partially engaged state in which a portion of the input torque is transformed into the output torque, and a fully disengaged state. A controller is coupled to the at least one clutch and configured to generate clutch commands based at least in part on the engine speed to position the at least one clutch into the fully engaged state, the partially engaged state, or the fully disengaged state.

A hybrid vehicle drive system including an internal combustion engine, a motor-generator, a speed shift mechanism including a first and second frictional engagement mechanisms, a torque limiter interposed the motor generator and the speed shift mechanism in a power transmission path transmitting from the internal combustion engine to an axle, and a controller controlling the speed shift mechanism so as to disengage the first frictional engagement mechanism and engage the second frictional engagement mechanism. The controller is configured to perform controlling the speed shift mechanism so as to increase an engaging force of the second frictional engagement mechanism during switching from high speed stage to low speed stage when an occurrence of slipping is detected than when the occurrence of slipping is not detected.