To provide a valve timing control device for internal combustion engine capable of ensuring a proper valve timing by preventing cam phase hunting in a cam phase holding state, and thereby improving the fuel consumption and the exhaust gas properties.
This valve timing control device for internal combustion engines is provided with actual cam phase detecting means 2, 28, 29 for detecting a cam phase CAIN; a cam phase setting means 2 for setting a target cam phase CAINCMD in response to the operating condition; oil pressure drop discriminating means 34, 2 for discriminating the oil pressure drop of timing advance chamber 11 and a timing delay chamber 12; a control means 2 for feedback control of a control signal value DOUTVT to an oil pressure control valve 10 when the deviation DCAINCMD of the target cam phase CAINCMD from the actual cam phase CAIN is below specified values DCAINFFR, DCAINFFA, and increasing or decreasing the control signal value DOUTVT to the oil pressure control valve 10 by specified quantities DVINPBP, DVINBM in a specified cycle TMDVPB when the oil pressure drop is discriminated.
WAKUI MASAYUKI
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