Control device for vehicular drive system

A control device for a vehicular drive system comprising (a) a continuously-variable transmission portion including a differential mechanism operable to distribute an output of an engine to a first electric motor and a power transmitting member, and further including a second electric motor disposed in a power transmitting path between said power transmitting member and a drive wheel of a vehicle, said continuously-variable transmission portion functioning as an electrically controlled continuously variable transmission, and (b) a step-variable transmission portion constituting a portion of said power transmitting path and functioning as a step-variable automatic transmission, said control device comprising:

• a differential-state switching device provided in said differential mechanism and operable to switch said continuously-variable transmission portion between a differential state in which said continuously-variable transmission portion is operable as the electrically controlled continuously variable transmission, and a non-differential state in which said continuously-variable transmission portion is not operable as the electrically controlled continuously variable transmission;
• and
• an engine speed control portion operable during a shifting control of said step-variable transmission portion, for controlling a speed of said engine during the shifting control of said step-variable transmission portion in one of two engine speed control methods which is selected depending upon whether the power distributing mechanism is placed in said differential state or said non-differential state upon initiation of the shifting control of the step-variable transmission portion.

A control device for a vehicular drive system comprising (a) a continuously-variable transmission portion including a differential mechanism operable to distribute an output of an engine to a first electric motor and a power transmitting member, and further including a second electric motor disposed in a power transmitting path between said power transmitting member and a drive wheel of a vehicle, said continuously-variable transmission portion functioning as an electrically controlled continuously variable transmission, and (b) a step-variable transmission portion constituting a portion of said power transmitting path and functioning as a step-variable automatic transmission, said control device comprising:

• a differential-state switching device provided in said differential mechanism and operable to switch said continuously-variable transmission portion between a differential state in which said continuously-variable transmission portion is operable as the electrically controlled continuously variable transmission, and a non-differential state in which said continuously-variable transmission portion is not operable as the electrically controlled continuously variable transmission;
• and
• an engine speed control portion operable during a shifting control of said step-variable transmission portion, for controlling a speed of said engine during the shifting control of said step-variable transmission portion, by changing a method of the shifting control of said step-variable transmission portion depending upon whether the power distributing mechanism is placed in said differential state or said non-differential state upon initiation of the shifting control of the step-variable transmission portion.