Shift control system for vehicle

A shift control system for a vehicle comprising a transmission,

• wherein a shift mode of the transmission may be selected at least from
• a manual mode in which a shifting operation of the transmission is executed in response to a manual shifting operation performed by a driver, and
• an automatic mode in which the shifting operation of the transmission is executed automatically in accordance with a traveling condition of the vehicle governed at least by a speed of the vehicle and a drive demand, and
• an automatic upshifting by which the upshifting is executed automatically to reduce a speed ratio of the transmission may be selectively inhibited,
• the shift control system comprises a controller that controls the speed ratio in different manners in the automatic mode and in the manual mode, and
• the controller comprises
• a mode determiner configured to determine that the manual mode is selected,
• an inhibition determiner configured to determine that the automatic upshifting is inhibited,
• a manual operation detector configured to determine that a manual downshifting operation is performed by the driver to increase the speed ratio,
• a vehicle speed detector configured to detect a value of a speed of the vehicle or a parameter corresponding to the speed of the vehicle, and
• a permissible value determiner configured to set a permissible value of the speed of the vehicle or the parameter corresponding to the speed of the vehicle at which the downshifting is permitted to be executed in response to an execution of the manual shifting operation, and
• the permissible value determiner is further configured to set the permissible value to a higher value in a case that the automatic upshifting is inhibited compared to the permissible value set in the case that the automatic upshifting is not inhibited.