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US 7,441,524 B2Granted
Valve timing control apparatus for internal combustion engine and control method thereof
AssigneeHitachi, Ltd.
InventorsNaoki Okamoto, Masahiko Watanabe, Yoshiyuki Kobayashi
Life of this patent
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Abstract
In a structure with a variable valve timing mechanism which varies an opening-and-closing timing of an intake valve and/or an exhaust valve due to a rotational phase of a camshaft with respect to a crankshaft of an internal combustion engine being varied, the rotational phase is detected in an arbitrary timing regardless of a rotational period of the camshaft, and the variable valve timing mechanism is controlled on the basis of the detected rotational phase.
Claims23
A valve timing control apparatus for an internal combustion engine comprising:
- a variable valve timing mechanism which varies an opening-and-closing timing of an intake valve and/or an exhaust valve due to a rotational phase of a camshaft with respect to a crankshaft of an engine being varied;
- a rotational phase detecting unit which is able to directly detect said rotational phase in an arbitrary timing without detecting rotational angles of said crankshaft and said camshaft;
- and
- a control unit which controls said variable valve timing mechanism on the basis of the rotational phase directly detected by said rotational phase detecting unit.
1 more element
A valve timing control apparatus for an internal combustion engine comprising:
- a variable valve timing mechanism which varies an opening-and-closing timing of an intake valve and/or an exhaust valve due to a rotational phase of a camshaft with respect to a crankshaft of an engine being varied;
- rotational phase detecting means for being able to directly detect said rotational phase in an arbitrary timing without detecting rotational angles of said crankshaft and said camshaft;
- and
- control means for controlling said variable valve timing mechanism on the basis of the rotational phase directly detected by said rotational phase detecting means.
1 more element
A valve timing control apparatus for an internal combustion engine comprising:
- a variable valve timing mechanism which varies an opening-and-closing timing of an intake valve and/or an exhaust valve due to a rotational phase of a camshaft with respect to a crankshaft of an engine being varied;
- a rotational speed sensor which detects an engine rotational speed;
- a crank angle sensor which detects a reference rotational position of said crankshaft;
- a cam sensor which detects a reference rotational position of said camshaft;
- a first rotational phase detecting unit which detects said rotational phase at each rotational period of said camshaft on the basis of output signals from said crank angle sensor and said cam sensor;
- a second rotational phase detecting unit which is able to directly detect said rotational phase in an arbitrary timing without detecting rotational angles of said crankshaft and said camshaft;
- and
- a control unit which controls said variable valve timing mechanism on the basis of the rotational phase detected by said second rotational phase detecting unit when an engine rotational speed is less than or equal to a predetermined rotational speed, and on the other hand, which controls said variable valve timing mechanism on the basis of the rotational phase detected by said first rotational phase detecting unit when an engine rotational speed is greater than said predetermined rotational speed.
5 more elements
A valve timing control apparatus for an internal combustion engine comprising:
- a variable valve timing mechanism which varies an opening-and-closing timing of an intake valve and/or an exhaust valve due to a rotational phase of a camshaft with respect to a crankshaft of an engine being varied;
- a rotational speed sensor which detects an engine rotational speed;
- a crank angle sensor which detects a reference rotational position of said crankshaft;
- a cam sensor which detects a reference rotational position of said camshaft;
- a first rotational phase detecting unit which detects said rotational phase at each rotational period of said camshaft on the basis of output signals from said crank angle sensor and said cam sensor;
- a rotator which rotates along with said camshaft, and in which a distance from a center of the camshaft to an outer periphery thereof varies in a circumferential direction;
- a first rotational angle sensor which detects a rotational angle of said crankshaft;
- a second rotational angle sensor which detects a rotational angle of said camshaft in accordance with a gap formed between the outer periphery of said rotator;
- a second rotational phase detecting unit which is able to detect said rotational phase in an arbitrary timing on the basis of output signals from said first rotational angle sensor and said second rotational angle sensor;
- and
- a control unit which controls said variable valve timing mechanism on the basis of the rotational phase detected by said second rotational phase detecting unit when an engine rotational speed is less than or equal to a predetermined rotational speed, and on the other hand, which controls said variable valve timing mechanism on the basis of the rotational phase detected by said first rotational phase detecting unit when an engine rotational speed is greater than said predetermined rotational speed.
8 more elements
A valve timing control apparatus for an internal combustion engine comprising:
- a variable valve timing mechanism which varies an opening-and-closing timing of an intake valve and/or an exhaust valve due to a rotational phase of a camshaft with respect to a crankshaft of an engine being varied;
- a rotational speed sensor which detects an engine rotational speed;
- a crank angle sensor which detects a reference rotational position of said crankshaft;
- a cam sensor which detects a reference rotational position of said camshaft;
- first rotational phase detecting means for detecting said rotational phase at each rotational period of said camshaft on the basis of output signals from said crank angle sensor and said cam sensor;
- second rotational phase detecting means for being able to directly detect said rotational phase in an arbitrary timing without detecting rotational angles of said crankshaft and said camshaft;
- and
- control means for controlling said variable valve timing mechanism on the basis of the rotational phase directly detected by said second rotational phase detecting means when an engine rotational speed is less than or equal to a predetermined rotational speed, and on the other hand, for controlling said variable valve timing mechanism on the basis of the rotational phase detected by said first rotational phase detecting means when an engine rotational speed is greater than said predetermined rotational speed.
5 more elements
A valve timing control method for an internal combustion engine having a variable valve timing mechanism which varies an opening-and-closing timing of an intake valve and/or an exhaust valve due to a rotational phase of a camshaft with respect to a crankshaft of an engine being varied, comprising the steps of:
- directly detecting said rotational phase in an arbitrary timing without detecting rotational angles of said crankshaft and said camshaft;
- and
- controlling said variable valve timing mechanism on the basis of the detected rotational phase.
A valve timing control method for an internal combustion engine having a variable valve timing mechanism which varies an opening-and-closing timing of an intake valve and/or an exhaust valve due to a rotational phase of a camshaft with respect to a crankshaft of an engine being varied, comprising the steps of:
- detecting an engine rotational speed;
- detecting a reference rotational position of said crankshaft and a reference rotational position of said camshaft;
- detecting said rotational phase at each rotational period of said camshaft on the basis of the reference rotational position of said crankshaft and the reference rotational position of said camshaft which have been detected;
- directly detecting said rotational phase in an arbitrary timing without detecting rotational angles of said crankshaft and said camshaft;
- and
- controlling said variable valve timing mechanism on the basis of the rotational phase directly detected in said arbitrary timing when an engine rotational speed is less than or equal to a predetermined rotational speed, and on the other hand, controlling said variable valve timing mechanism on the basis of the rotational phase detected at each rotational period of said camshaft when an engine rotational speed is greater than said predetermined rotational speed.
3 more elements
Dependencies are inferred from the claim text.