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US 7,398,751 B2Granted
Control device for engine valve and control system for engine
AssigneeDenso Corporation
InventorHisashi Kadowaki
Life of this patent
Estimating the term…
Abstract
A rotational phase difference of a camshaft relative to a crankshaft in a variable valve timing mechanism is controlled by an operation of an oil control valve. That is, in the oil control valve, there is outputted an operational signal which is defined by adding a feedback correction amount corresponding to a difference between an actual value and a target value of the rotational phase difference, to a holding learning value as the operational signal for holding the rotational phase difference. The holding learning value is altered only by a specified value on condition that the operational signal for holding the rotational phase difference is assumed to change.
Claims13
A control device of an engine valve comprising:
- a rotational phase difference-adjusting means which varies a rotational phase difference of a camshaft relative to a crankshaft to adjust operating timing of an engine valve;
- a crank angle detector for detecting a rotational angle of the crankshaft;
- a cam angle detector for detecting a rotational angle of the camshaft;
- a phase difference-calculating means which calculates the rotational phase difference based upon a detection value of the crank angle detector and a detection value of the cam angle detector;
- a learning means which learns a holding learning value as an operational signal of the rotational phase difference-adjusting means for holding the rotational phase difference;
- a calculating means which calculates a feedback correction amount in accordance with a difference between an actual value and a target value of the rotational phase difference;
- a control means which feedback-controls the actual value to the target value by operating the rotational phase difference-adjusting means with the feedback correction amount by setting the holding learning value as a reference;
- and
- an alteration means which alters the holding learning value as the reference only by a specified value on condition that the operational signal for holding the rotational phase difference is assumed to change.
6 more elements
A control device of an engine valve comprising:
- a phase difference-adjusting means which varies a rotational phase difference of a cam shaft relative to a crank shaft to adjust operating timing of an engine valve;
- a crank angle detector for detecting a rotational angle of the crankshaft;
- a cam angle detector for detecting a rotational angle of the camshaft;
- a phase difference-calculating means which calculates the rotational phase difference based upon a detection value of the crank angle detector and a detection value of the cam angle detector;
- a learning means which learns a holding learning value as an operational signal of the rotational phase difference-adjusting means for holding the rotational phase difference;
- a calculating means which calculates a feedback correction amount in accordance with a difference between an actual value and a target value of the rotational phase difference;
- and
- a control means which feedback-controls the actual value to the target value by operating the rotational phase difference-adjusting means with the feedback correction amount by setting the holding learning value as a reference;
- and
- an alteration means which alters the holding learning value only by a specified value to reduce a difference between the actual value and the target value when the difference is more than a predetermined value.
7 more elements
A control system of an engine valve comprising:
- a phase difference-adjusting means for varying a rotational phase difference of a camshaft relative to a crankshaft to adjust operational timing of the engine valve;
- a crank angle detecting means for detecting a rotational angle of the crankshaft;
- a cam angle detecting means for detecting a rotational angle of the camshaft;
- a phase difference-calculating means for calculating the rotational phase difference based upon a detection value of the crank angle detecting means and a detection value of the cam angle detecting means;
- a learning means for learning a holding learning value as an operational signal of the rotational phase difference-adjusting means for holding the rotational phase difference;
- a calculating means for calculating a feedback correction amount in accordance with a difference between a target value and an actual value of the rotational phase difference;
- a control means for feedback-controlling the actual value to the target value by operating the rotational phase difference-adjusting means with the feedback correction amount by setting the holding learning value as a reference;
- and
- an alteration means for altering the holding learning value as the reference only by a specified value on condition that the operational signal for holding the rotational phase difference is assumed to change.
6 more elements
Dependencies are inferred from the claim text.