Abnormality determination apparatus for internal combustion engine

Patent metadata

Field	Value
Publication number	US-11078863-B2
Application number	US-202016783759-A
Country	US
Kind code	B2
Filing date	Feb 6, 2020
Priority date	Feb 8, 2019
Publication date	Aug 3, 2021
Grant date	Aug 3, 2021

Abstract

An abnormality determination apparatus for an internal combustion engine in which an intake passage upstream of a supercharger and a crankcase are connected by a breather line includes: an intake flow rate detection unit that detects an intake flow rate in the intake passage; and an abnormality determination unit that determines abnormality of the breather line. The abnormality determination unit accumulates a value calculated from a rotation second-order component of a fluctuation waveform of the intake flow rate over a predetermined period of time and determines the abnormality of the breather line when the accumulated value is less than a predetermined threshold.

First claim

What is claimed is:

1. An abnormality determination apparatus for an internal combustion engine in which a crankcase and an intake passage upstream of a forced-induction system are connected by a breather line, comprising:
an intake flow rate detection detector that detects an intake flow rate in the intake passage; and
an abnormality determination unit that determines abnormality of the breather line, wherein
the abnormality determination unit accumulates a value calculated from a rotation second-order component of a fluctuation waveform of the intake flow rate over a predetermined period of time to obtain an accumulated value and determines occurrence of the abnormality of the breather line when the accumulated value is less than a predetermined threshold.

2. The abnormality determination apparatus for an internal combustion engine according to claim 1 , wherein
the accumulated value is obtained by accumulating an absolute value of the rotation second-order component of the fluctuation waveform of the intake flow rate over the predetermined period of time.

3. The abnormality determination apparatus for an internal combustion engine according to claim 1 , wherein
the accumulated value is obtained by accumulating a difference in one cycle between a maximum value and a minimum value of the rotation second-order component of the fluctuation waveform of the intake flow rate over the predetermined period of time.

4. The abnormality determination apparatus for an internal combustion engine according to claim 1 , wherein
the rotation second-order component is calculated by multiplying the fluctuation waveform of the intake flow rate by a sine wave and a cosine wave corresponding to an angular velocity of a crank, followed by integration.

5. The abnormality determination apparatus for an internal combustion engine according to claim 1 , wherein
the rotation second-order component represents a rotation second-order fluctuation generated in an internal pressure of the crankcase.

6. An abnormality determination method of an internal combustion engine in which a crankcase and an intake passage upstream of a forced-induction system are connected by a breather line, the method comprising steps of:
detecting by an intake flow rate detection detector an intake flow rate in the intake passage;
accumulating by a computer a value calculated from a rotation second-order component of a fluctuation waveform of the intake flow rate over a predetermined period of time to obtain an accumulated value; and
determining by the computer occurrence of the abnormality of the breather line when the accumulated value is less than a predetermined threshold.

Assignees

• Honda Motor Co Ltd

Inventors

• Sekiguchi Toru
• Konomoto Takashi
• Yoshida Toshifumi

Classifications

• F01M2013/0077

  Engine parameters used for crankcase breather systems · CPC title

• F02D41/22 Primary

  Safety or indicating devices for abnormal conditions {(in air/fuel ratio feedback systems F02D41/1495, in electric control linkage F02D11/107, in purge control systems F02M25/0809)} · CPC title

• F01M13/023

  Control valves in suction conduit · CPC title

• F02D2041/1432

  the system including a filter, e.g. a low pass or high pass filter · CPC title

• F01M13/021

  of negative pressure · CPC title