| 摘要 |
PURPOSE:To reduce the driving requisite power in an oil pump by setting braking oil pressure in a transmission according to a valve operating characteristic selectively set up, in a power unit including an engine that the valve operating characteristic of at least one side of both intake and exhaust valves is made selectable. CONSTITUTION:A power unit is provided with an engine E, having a variable valve timing lift mechanism VT which selects the on-off timing of an intake valve of the engine E and its opening period and lift to a low-speed valve operating characteristic suitable for a low speed area and a high-speed valve operating characteristic suitable for a high speed area, and an automatic transmission AT being controlled by a hydraulic control valve CV. In this case, when the valve operating characteristic is selected by the variable valve timing lift mechanism VT, control oil pressure of the automatic transmission AT, namely, line pressure is controlled by a regulator valve of the hydraulic control valve CV to be set to such one suited to the valve operating characteristic at the time. |
