| 摘要 |
A control system for an engine is provided. The system includes a hydraulically-operated variable valve timing mechanism, a variable oil pump, and a hydraulic-pressure control valve. The variable valve timing mechanism has advance-side and retard-side operation chambers and a locking mechanism. The system includes a hydraulic-pressure sensor for detecting hydraulic pressure within a hydraulic-pressure path, and a pump control device for performing a target hydraulic-pressure control. During a change of an engine operating state in a specific operation of the engine, while an unlocking operation of a locking member of the locking mechanism is performed, the pump control device performs, instead of the target hydraulic-pressure control, a discharge amount restricting control to control the hydraulic pressure to be an upper-limit hydraulic-pressure value or lower, which is an upper limit to perform the unlocking operation. |
| 主权项 |
1. A control system for an engine, the control system including a hydraulically-operated variable valve timing mechanism, a variable oil pump, and a hydraulic-pressure control valve, the hydraulically-operated variable valve timing mechanism having advance-side and retard-side operation chambers that are formed by a housing for rotating in cooperation with a crankshaft of the engine and a vane body for integrally rotating with a camshaft, and change a phase angle of the camshaft with respect to the crankshaft by supplying hydraulic pressure, and a locking mechanism that unlocks, by supplying hydraulic pressure, a locking member for fixing the phase angle of the camshaft with respect to the crankshaft, the variable oil pump configured to supply, via a hydraulic-pressure path, oil to hydraulically-operated devices including the variable valve timing mechanism of the engine, the hydraulic-pressure control valve controlling the hydraulic pressure to be supplied to the locking mechanism and the advance-side and retard-side operation chambers, the control system comprising:
a hydraulic-pressure sensor for detecting the hydraulic pressure within the hydraulic-pressure path; and a pump control device for performing a target hydraulic-pressure control for controlling an oil discharge amount of the variable oil pump to control the hydraulic pressure that is to be detected by the hydraulic-pressure sensor to be a target hydraulic pressure set according to an operating state of the engine, wherein during a change of the operating state of the engine in a specific operation of the engine in which the locking member of the locking mechanism is in a locked state, while an unlocking operation of the locking member is performed, the pump control device performs, instead of the target hydraulic-pressure control, a discharge amount restricting control for restricting the oil discharge amount of the variable oil pump to control the hydraulic pressure that is to be detected by the hydraulic-pressure sensor to be an upper-limit hydraulic-pressure value or lower, the upper-limit hydraulic-pressure value being an upper limit for the unlocking operation of the locking member to be performed. |
