Misfire detection system for internal combustion engine
AssigneeHonda Motor Co., Ltd.
InventorsYuji Yasui, Masahiro Sato
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Abstract
In a misfire detection system for an internal combustion engine, a product is calculated at every predetermined crank angle by multiplying a value retrieved from a periodic function defined to model torque generation of individual cylinders synchronously with each combustion cycle, by a detected crank angle velocity, and the product is integrated over a predetermined interval to calculate an integral. The integral is then compared with a predetermined value and is detected whether misfire has occurred in one of the individual cylinders, thereby enabling to detect misfire even when misfire occurs successively in a multiple cylinder engine, identify the misfiring cylinders with good accuracy.
Claims12
A system for detecting a misfire of an internal combustion engine having a plurality of cylinders, comprising:
- a crank angle sensor detecting a crank angle velocity at every predetermined crank angle;
- a calculator calculating a product at the every predetermined crank angle by multiplying a value retrieved from a periodic function defined to model torque generation of individual cylinders synchronously with each combustion cycle, by the detected crank angle velocity, and integrating the calculated product over a predetermined interval to calculate an integral of the product;
- and
- a misfire discriminator comparing the calculated integral with a predetermined value and detecting whether misfire has occurred in one of the individual cylinders based on a result of the comparison.
A method of detecting a misfire of an internal combustion engine having a plurality of cylinders, comprising the steps of:
- (a) detecting a crank angle velocity at every predetermined crank angle;
- (b) calculating a product at the every predetermined crank angle by multiplying a value retrieved from a periodic function defined to model torque generation of individual cylinders synchronously with each combustion cycle, by the detected crank angle velocity, and integrating the calculated product over a predetermined interval to calculate an integral of the product;
- and
- (c) comparing the calculated integral with a predetermined value and detecting whether misfire has occurred in one of the individual cylinders based on a result of the comparison.
Dependencies are inferred from the claim text.