Back to results
US 2012/0055429 A1Published application
Variable valve timing control apparatus
AssigneeDenso Corporation
InventorsTakayoshi Nakamura, Haruyuki Urushihata
Life of this patent
Estimating the term…
Abstract
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.
Claims14
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 lock pin to lock the VCT phase at a predetermined lock phase positioned in a controllable range of the VCT phase;
- an oil pressure control valve to control an oil pressure that drives the variable valve timing device and the lock pin;
- a VCT phase controller 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 to determine whether there is an abnormality in a system of the VCT phase control;
- and
- a valve controller 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.
4 more elements
A variable valve timing control apparatus comprising:
- a variable valve timing device that controls valve timing of an intake 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 lock pin to lock the VCT phase at a middle lock phase located middle between a most retard phase and a most advance phase in a controllable range of the VCT phase;
- an oil pressure control valve to control an oil pressure that drives the variable valve timing device and the lock pin;
- a VCT phase controller 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 engine stall predicting portion to predict whether a stall will be generated in the engine;
- and
- a valve controller to control a control amount of the oil pressure control valve regardless of the VCT phase (i) so as to drive the lock pin in a locking direction to lock the VCT phase or/and (ii) so as to drive the VCT phase in an advance direction, when the engine stall predicting portion predicts that a stall will be generated in the engine.
4 more elements
A variable valve timing control apparatus comprising:
- a variable valve timing device that controls valve timing of an 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 lock pin to lock the VCT phase at a middle lock phase located middle between a most retard phase and a most advance phase in a controllable range of the VCT phase;
- an oil pressure control valve to control an oil pressure that drives the variable valve timing device and the lock pin;
- a VCT phase controller 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 engine stall predicting portion to predict whether a stall will be generated in the engine;
- and
- a valve controller to control a control amount of the oil pressure control valve regardless of the VCT phase (i) so as to drive the lock pin in a locking direction to lock the VCT phase or/and (ii) so as to drive the VCT phase in a retard direction, when the engine stall predicting portion predicts that a stall will be generated in the engine.
4 more elements
Dependencies are inferred from the claim text.