A control system and method for controlling a continuously variable transmission in a vehicle propulsion system includes measuring a speed ratio of the continuously variable transmission, determining whether the measured speed ratio is drifting away from a commanded speed ratio, and adjusting the commanded speed ratio to a value that is different than a desired speed ratio if the measured speed ratio is drifting away from the commanded speed ratio.

A control apparatus for a drive-force transmitting apparatus that includes a transmission having primary and secondary pulleys. When a detection accuracy of rotational speed of the primary and secondary pulley is not assured, the control apparatus sets each of (i) a secondary-thrust calculation thrust ratio value used for calculation of a secondary thrust that is to be applied to the secondary pulley and (ii) a primary-thrust calculation thrust ratio value used for calculation of a primary thrust that is to be applied to the primary pulley, such that each of the secondary-thrust calculation thrust ratio value and the primary-thrust calculation thrust ratio value is dependent on a result of a determination as to whether an actual gear ratio of the transmission is the highest gear ratio and a result of a determination as to whether an input torque inputted to the transmission is lower than a given torque value.

A position controller includes: an oil temperature acquisition unit that acquires information on an oil temperature of a hydraulic actuator; a position acquisition unit that acquires an actual value of an operation position of an object; a position control unit that calculates an operation command value for a control valve of the hydraulic actuator by closed-loop control so as to reduce a deviation between a target value of the operation position of the object and the actual value; and a gain setting unit that changes at least one gain of the closed-loop control so that sensitivity of the closed-loop control increases as the oil temperature decreases.

A shift control device has stepless and stepped shift modes in which a transmission gear ratio of a continuously variable transmission is controlled in stepless and stepwise fashions, respectively, and includes a mode setting unit that switches the shift mode to the stepped shift mode if an engine rotation speed in the stepless shift mode exceeds a switch threshold, a correction-value setting unit that sets a correction value based on the engine rotation speed if the shift mode is to be switched to the stepped shift mode, a shift-threshold setting unit that sets a shift threshold by adding the correction value to the switch threshold if the shift mode is to be switched to the stepped shift mode, and an upshift controller that switches the transmission gear ratio toward a higher side when the engine rotation speed in the stepped shift mode reaches the shift threshold.

An apparatus for learning gear ratio control of a CVT (Continuously Variable Transmission) may include: an APS (Acceleration Position Sensor) configured to detect a change of an accelerator pedal in a CVT vehicle; a gear ratio detector configured to detect a pulley gear ratio of the CVT; a timer configured to measure the time during which gear ratio control learning is performed during power-off up-shift of the CVT; and a controller configured to receive the values detected through the APS, the gear ratio detector and the timer, and control the CVT to shift gears at a target gear ratio learned through the gear ratio control learning, during the power-off up-shift by coasting.

In a vehicle in which a continuously variable transmission, which is connected to an electric motor via a clutch, is operated using oil pressure of an oil pump driven by the motor, erroneous engagement of the clutch is quickly determined. The vehicle has the motor serving as a vehicle driving source, the oil pump connected to the motor, the continuously variable transmission, the clutch interposed between the motor and the continuously variable transmission, a clutch control means for controlling the clutch such that the clutch enters into a completely-engaged, slip-engaged, or release state, and a vehicle control means for controlling the motor such that the motor rotates at a target rotation speed. Also provided is an erroneous engagement handling control means that executes torque adjustment control to decrease an output torque of the vehicle driving source when the clutch is determined to be in an erroneously completely engaged state.

A failure judgment device of an automatic transmission includes: a first abnormality judging section configured to judge a power supply fault abnormality or a breaking abnormality of the solenoid, from a selected shift stage and a state of the transmission mechanism, after the detection of the electric abnormality; and a second abnormality judging section configured to judge the power supply abnormality or the breaking abnormality of the solenoid, from the monitor current value when the solenoid valve is switched to an OFF state, after the detection of the electric abnormality, when one of the first abnormality judging section and the second abnormality judging section judges the power supply fault abnormality or the breaking abnormality, the judgement result being outputted.

A transmission assembly includes a ring gear configured to receive an input torque from a power source, a carrier assembly coupled to the ring gear, the carrier assembly configured to rotate about a first axis and including a housing, and a spider gear rotatably coupled to the housing, a carrier outlet shaft including a carrier outlet gear in meshed engagement with the spider gear, wherein the carrier outlet shaft is configured to transmit an output torque to a driveshaft, a control shaft including a control gear in meshed engagement with the spider gear, and a load applicator coupled to the control shaft, wherein the load applicator is configured to provide a resistive torque to the control shaft to resist rotation of the control shaft and vary a gear ratio between the driveshaft and the input shaft.

A control apparatus for a vehicle drive-force transmitting apparatus that includes a gear mechanism and a continuously-variable transmission mechanism including a primary pulley, a secondary pulley, a transfer element that is looped over the primary and secondary pulleys, and an actuator configured to apply, to the primary pulley, a thrust, based on which the transfer element is to be clamped by the primary pulley. The vehicle drive-force transmitting apparatus defines a first drive-force transmitting path for transmitting a drive force through the gear mechanism and a second drive-force transmitting path for transmitting the drive force through the continuously-variable transmission mechanism. The control apparatus is configured, upon vehicle deceleration with the first drive-force transmitting path being established, to set a lower limit value of the above-described thrust, based on a gear ratio of the continuously-variable transmission mechanism and an amount of change of a rotational speed of the primary pulley.

In a control device of a vehicle power transmission device, a first meshing clutch has a drive power source side meshing member coupled to a power transmission member, an auxiliary drive wheel side meshing member coupled to the power transmission member, and an actuator engaging or releasing the drive power source side meshing member and the auxiliary drive wheel side meshing member, and when a rotation speed difference between a rotation speed of the drive power source side meshing member and a rotation speed of the auxiliary drive wheel side meshing member is larger than a predefined value at the time when a first meshing clutch is brought into an engaged state, a clamping pressure on a transmission belt is increased as compared to when a rotation speed difference is equal to or less than a predefined value.