Transmission control method and transmission control device for continuously variable transmission

A transmission control device for a continuously variable transmission, the transmission control device comprising:

• an engine;
• a continuously variable transmission connected to an input side of the engine;
• and
• a transmission controller configured to perform a control while traveling to select a shifting mode from among a normal transmission mode for changing a transmission ratio in a stepless manner, and a pseudo-stepped transmission mode for changing the transmission ratio in a stepwise manner;
• the transmission controller including:
• a pseudo-stepped downshift mode as the pseudo-stepped transmission mode, in which a transmission input rotational speed is increased to a downshift target rotational speed in a stepwise manner, and then decreased toward a lower-limit target rotational speed as a vehicle speed decreases;
• setting the downshift target rotational speed and the lower-limit target rotational speed used for the pseudo-stepped downshift to values in an engine rotational speed region in which an engine output becomes greater than or equal to a prescribed value;
• shifting to the pseudo-stepped downshift mode to start the pseudo-stepped downshift when a mode transition condition is satisfied during deceleration by selecting the normal transmission mode;
• and
• executing a process for repeating an increase to the downshift target rotational speed and a decrease to the lower-limit target rotational speed of the transmission input rotational speed, when the pseudo-stepped downshift is initiated, until a mode cancellation condition, including a re-acceleration request, is satisfied.