Control apparatus for continuously variable transmission of vehicle

A control apparatus for a continuously variable transmission capable of continuously transmitting the output of an internal combustion engine equipped in a vehicle, said control apparatus configured to control the transmission ratio of said continuously variable transmission in one of transmission modes including a continuously variable transmission mode for continuously setting the transmission ratio of said continuously variable transmission and a stepped transmission mode for setting the transmission ratio on a step-by-step basis, said control apparatus comprising:

• operating condition detecting means for detecting an operating condition of said vehicle;
• target transmission ratio setting means for setting a target transmission ratio in accordance with a detected operating condition of said vehicle;
• transmission ratio control means for controlling the transmission ratio of said continuously variable transmission to reach the set target transmission ratio;
• transmission mode switching means for switching the transmission mode between said continuously variable transmission mode and said stepped transmission mode;
• and
• rotational speed detecting means for detecting the rotational speed of said internal combustion engine,
• wherein said target transmission ratio setting means is operable when the transmission mode is switched from said continuously variable transmission mode to said stepped transmission mode to set said target transmission ratio to a transmission ratio in said continuously variable transmission mode immediately before the switching, and is operable when the rotational speed of said internal combustion engine subsequently reaches a first predetermined value to set said target transmission ratio to a transmission ratio on a high speed side such that the rotational speed of said internal combustion engine is reduced to a second predetermined value smaller than said first predetermined value,
• wherein said vehicle comprises an operating means operated by an operator of said vehicle for changing the transmission ratio of said continuously variable transmission,
• wherein said operating condition detecting means includes running state detecting means for detecting whether or not said vehicle is in a predetermined starting state, a predetermined stopping state, or a predetermined sudden accelerating state, and whether or not said operating means is in a predetermined operating state, and
• wherein said transmission mode switching means is responsive to one of said predetermined starting state, stopping state, sudden accelerating state of said vehicle and said predetermined operating state detected by said running state detecting means for prohibiting execution of said stepped transmission mode.