Variable valve timing control apparatus

摘要

A variable valve timing control apparatus includes an abnormality determining portion and a valve controller. The abnormality determining portion determines whether there is an abnormality in a system of a VCT phase control in which an oil pressure control valve is controlled in a manner that an actual VCT phase coincides with a target phase. The valve controller controls the oil pressure control valve to drive a lock pin in a locking direction so as to lock the VCT phase when the abnormality determining portion determines that there is an abnormality in the system of the VCT phase control.

主权项

1. A variable valve timing control apparatus comprising:
a variable valve timing device that controls valve timing of an intake valve or exhaust valve by changing a rotation phase of a camshaft with respect to a crankshaft in an engine, the rotation phase of the camshaft with respect to the crankshaft being defined as a VCT phase; a plurality of restricting pins to limit the VCT phase, wherein at least one of the plurality of restricting pins is a lock pin to lock the VCT phase at a predetermined lock phase positioned in a controllable range of the VCT phase, and wherein the predetermined lock phase is a middle lock phase located between a most retard phase and a most advance phase in the controllable range of the VCT phase; an oil pressure control valve to control an oil pressure that drives the variable valve timing device and each of the plurality of the restricting pins; and a control circuit configured to include:
a VCT phase controller configured to perform a VCT phase control in which the oil pressure control valve is controlled in a manner that an actual VCT phase coincides with a target phase;an abnormality determining portion configured to determine whether there is an abnormality in a system of the VCT phase control, wherein the abnormality determining portion is configured to determine that there is an abnormality in the system of the VCT phase control when at least one of the plurality of restricting pins is incapable to have normal projection to lock the VCT phase while the plurality of restricting pins is controlled to project so as to limit the VCT phase; and a valve controller configured to control a control amount of the oil pressure control valve so as to drive the lock pin in a locking direction to lock the VCT phase regardless of the VCT phase when the abnormality determining portion determines that there is an abnormality in the system of the VCT phase control, wherein the valve controller controls the control amount of the oil pressure control valve so as to drive the plurality of restricting pins in a projecting direction to lock the VCT phase when the abnormality determining portion determines that there is an abnormality in the system of the VCT phase control.