Patent ID: 8788129

Claim:
A control device for controlling a transmission device that includes an input member drivably coupled to an engine and a rotary electric machine capable of producing regenerative torque on the basis of a request to decelerate a vehicle, an output member drivably coupled to wheels, and a speed change mechanism that has a plurality of friction engagement elements that are controllably engaged and disengaged to switch between a plurality of shift speeds, and that outputs rotation of the input member to the output member while changing a rotational speed with a speed ratio of each shift speed, the control device comprising: a predicted input torque prediction unit that predicts a predicted value of input torque input into the input member at a predetermined determination reference time later on the basis of variations in the input torque; and a negative torque prediction established state determination unit that determines a negative torque prediction established state in which the predicted input torque is a regenerative torque output by the rotary electric machine, wherein when the speed change mechanism performs an upshift characterized by switching to a shift speed with a lower speed ratio in the negative torque prediction established state or in a small acceleration operation amount state in which an accelerator operation amount of the vehicle is equal to or less than a predetermined value, a special speed change control is executed in which a disengagement hydraulic pressure, which is a hydraulic pressure of hydraulic oil for the disengagement element that is a friction engagement element that is engaged before the upshift and disengaged after the upshift, is lowered to cause the disengagement element to slip, and the disengagement element is maintained in a slipping state over an entire speed change process, which extends from a time point when the disengagement element starts slipping to a time point when a rotational speed obtained by multiplying a rotational speed of the output member by a speed ratio after the switching between shift speeds is synchronized with a rotational speed of the input member, and wherein when the speed change mechanism performs the upshift and the vehicle is not in the negative torque prediction established state and the vehicle is not in the small acceleration operation amount state, a normal speed change control is executed in which the disengagement element is disengaged quickly in an initial stage of the speed change process and the disengagement element is not maintained in the slippage state over the entire speed change process.