Control device for vehicle drive device

Abstract

A control device for a drive device of a vehicle which is provided with an engine, a supercharger to raise a pressure of intake air introduced in said engine, an accelerating member manually operable by an operator of the vehicle to accelerate the vehicle, and an automatic transmission constituting a portion of a power transmitting path between said engine and drive wheels, and wherein said engine is placed in a first operating state in which said supercharger is operated, or a second operating state in which an operation of said supercharger is restricted as compared with that in said first operating state, said control device comprising: a speed ratio selection control portion configured to implement a speed ratio selection control to change a method of selecting a speed ratio of said automatic transmission depending upon a rate of increase of an operation amount of said accelerating member, where said engine will be placed in said first operating state if said automatic transmission is shifted to select a first speed ratio value according to a predetermined shifting map while said engine is placed in said second operating state, said speed ratio selection control portion implementing said speed ratio selection control to shift said automatic transmission to select said first speed ratio value when the rate of increase of the operation amount of said accelerating member is relatively low, and to shift said automatic transmission to select a second speed ratio value at which said engine is kept in said second operating state and which is higher than said first speed ratio value, when the rate of increase of the operation amount of said accelerating member is relatively high.

Description

TECHNICAL FIELD[0001]The present invention relates to techniques for improving a response of a vehicle to an operator's operation to accelerate the vehicle.BACKGROUND ART[0002]There is known a vehicle provided with an engine, a supercharger to raise the pressure of intake air introduced in the engine, and an automatic transmission constituting a portion of a power transmitting path between the engine and drive wheels. Patent Document 1 discloses a control device for a vehicular drive system used for this type of vehicle. In the vehicular drive system disclosed in Patent Document 1, the automatic transmission is a continuously variable transmission the speed ratio of which is continuously variable. The control device of Patent Document 1 is configured to control shifting actions of the automatic transmission such that a rate of change of the speed ratio (shifting speed) of the automatic transmission in an initial stage of a shifting action is made higher when a rate of change of an o...

AI Technical Summary

Benefits of technology

The present invention relates to a control device for vehicles that improves the response of the vehicle to the operator's actions when accelerating or shifting gears. The control device selects between two speed ratios based on the operator's actions and the engine's operating speed. When the engine is placed in a second operating state, the control device shifts to a first speed ratio to improve the vehicle's response. The control device also includes a speed ratio selection control that reduces the delay of the engine's response when shifting from the second operating state to the first operating state. Additionally, the control device can include a supercharger that raises the pressure of the intake air to improve the engine's response. These technical effects improve the vehicle's driving experience and fuel economy.

Problems solved by technology

The response of the vehicle may be insufficient to meet a degree of acceleration of the vehicle expected by the vehicle operator, depending upon the operating condition of the supercharger immediately after the vehicle operator's operation to accelerate the vehicle, or the rate of increase of the amount of operation of the accelerator pedal by the vehicle operator to accelerate the vehicle.

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