Control device for vehicle and control method thereof

Abstract

The invention provides a control device for a vehicle which decreases the vibration during shifting and prevents the fuel burnup from worsening. When a downshift is performed while a vehicle travels in a coasting state, a determination is made as to judge whether a fuel cut recovery will be performed. When a fuel cut recovery is performed, an offset oil pressure is set and an initial oil pressureset after raising an oil pressure of an engagement side frictional engagement element to a pre-charge oil pressure is set at an oil pressure obtained by subtracting the offset oil pressure from a reference initial oil pressure.

Description

technical field [0001] The present invention relates to a control device for a vehicle. Background technique [0002] Reference 1 discloses that when the automatic transmission downshifts while the vehicle is in a coasting state, relatively high oil pressure is supplied to the frictional engagement element on the engagement side to accelerate the piston stroke on the engagement side. Then, low-pressure hydraulic pressure (hereinafter referred to as initial hydraulic pressure) is supplied to complete the stroke. Thereafter, by increasing the oil pressure of the frictional engagement element on the engagement side from the initial oil pressure, the downshift in the automatic transmission is completed after passing through the torque phase and the inertia phase. [0003] Patent Document 1: (Japanese) Japanese Patent Publication No. 6-37931 [0004] Downshifting in the coasting state is performed in different operating states, such as when the engine speed is in a high speed r...

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Problems solved by technology

However, for example, in the case of fuel cut, the reverse driving force is greater than that after fuel supply recovery from fuel cut, and the initial oil pressure increase is high, although the driver feels the shifting vibration is suppressed, but the oil pressure is kept from excessive. Low initial oil pressure rise, therefore, the time to reach the specified oil pressure is prolonged

As a result, the time until the start of the inertia phase at the time of coasting downshifts performed during fuel cut becomes longer, during which the engine speed Ne decreases, and recovery from fuel cut is performed, which may cause vibration and fuel consumption when recovery from fuel cut is performed. worsening problem

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