Control apparatus for vehicle drive-force transmitting apparatus

A control apparatus for a drive-force transmitting apparatus that is to be provided in a vehicle having a drive force source and drive wheels,

• wherein the drive-force transmitting apparatus includes:
• a continuously-variable transmission mechanism which is configured to transmit a drive force of the drive force source toward the drive wheels, and which includes a primary pulley, a secondary pulley, and a transfer element that is looped over the primary and secondary pulleys, such that the primary pulley includes a primary hydraulic actuator configured to generate a primary thrust, based on which the transfer element is to be clamped by the primary pulley, and such that the secondary pulley includes a secondary hydraulic actuator configured to generate a secondary thrust, based on which the transfer element is to be clamped by the secondary pulley,
• wherein said control apparatus includes:
• a detection-accuracy determining portion configured to make a determination as to whether an accuracy of detection of at least one rotational speed that is to be used for calculation of an actual value of a gear ratio of the continuously-variable transmission mechanism, is assured or not;
• a highest-gear-ratio determining portion configured to make a determination as to whether an actual value of a gear ratio of the continuously-variable transmission mechanism is a highest gear ratio or not;
• an input-torque determining portion configured to make a determination as to whether an input torque inputted to the continuously-variable transmission mechanism is lower than a given torque value or not;
• and
• a transmission-shifting control portion configured to control a thrust ratio that is a ratio of the secondary thrust to the primary thrust, and to calculate, based on the input torque, a target-gear-ratio establishing ratio value of the thrust ratio that is for establishing a target value of the gear ratio, and
• wherein, when it is determined that the accuracy of the detection of the at least one rotational speed is not assured, said transmission-shifting control portion is configured to set each of (i) a secondary-thrust calculation thrust ratio value of the thrust ratio used for calculation of the secondary thrust based on the primary thrust and (ii) a primary-thrust calculation thrust ratio value of the thrust ratio used for calculation of the primary thrust based on the secondary thrust, by using a base thrust ratio that is the target-gear-ratio establishing ratio value of the thrust ratio, such that each of the set secondary-thrust calculation thrust ratio value and the set primary-thrust calculation thrust ratio value is dependent on a result of the determination as to whether the actual value of the gear ratio is the highest gear ratio or not and a result of the determination as to whether the input torque is lower than the given torque value or not.