Ignition timing control apparatus for internal combustion engine

Patent metadata

Field	Value
Publication number	US-10273929-B2
Application number	US-201615341397-A
Country	US
Kind code	B2
Filing date	Nov 2, 2016
Priority date	Nov 12, 2015
Publication date	Apr 30, 2019
Grant date	Apr 30, 2019

Abstract

When the concentration of alcohol is high, the timing of ignition is controlled upon the lapse of a delay time Tig from a reference timing t as a timing when a reference angle θref that is more advanced than a top dead center is detected. It should be noted, however, that the timing of ignition is controlled to a timing when a retarded angle aop is detected, if it is determined that a misfire has occurred.

First claim

What is claimed is:

1. An ignition timing control apparatus for an internal combustion engine, the internal combustion engine including a detection target provided with detected portions indicating a plurality of mutually different rotational angles of a crankshaft respectively, and a rotational angle sensor configured to detect a rotational angle of the crankshaft by detecting each of the detected portions, the ignition timing control apparatus comprising:
an electronic control unit configured to
i) set an angle command value of an ignition timing in starting the internal combustion engine,
ii) control the ignition timing of the internal combustion engine in accordance with the angle command value by operating an ignition device of the internal combustion engine,
iii) set a delay time of a timing in response to the rotational angle of the crankshaft becoming equal to the angle command value with respect to a reference timing, in accordance with the angle command value, the reference timing being a timing corresponding to a reference angle that is more advanced than a top dead center among timings of detection of the detected portions by the rotational angle sensor,
iv) control the ignition timing of the internal combustion engine to a timing upon lapse of the delay time from the reference timing in response to the angle command value not coinciding with any of rotational angles corresponding to the detection timings,
v) set the delay time based on a time interval among a plurality of the detection timings before setting the delay time,
vi) determine whether or not a misfire has occurred in starting the internal combustion engine, and
vii) change the angle command value of the ignition timing subsequent to detection of the misfire to a value that is more retarded than the angle command value at a time of the misfire in response to the electronic control unit determining that the misfire has occurred.

2. The ignition timing control apparatus according to claim 1 , wherein
the electronic control unit is configured to change the angle command value of the ignition timing subsequent to detection of the misfire to a value that is more retarded than the angle command value at the time of the misfire by setting the angle command value to a retarded angle, the retarded angle is a rotational angle that is determined by the detected portion that is located more retarded than the reference angle, and
the electronic control unit is configured to control the ignition timing to a retarded detection timing as the detection timing of the retarded angle, regardless of the delay time that is set by the electronic control unit, in response to the angle command value being equal to the retarded angle.

3. The ignition timing control apparatus according to claim 2 , wherein
the electronic control unit is configured to acquire degree-of-ease information, the degree-of-ease is information indicating whether or not a degree of ease of gasification is smaller than a prescribed value, the degree of ease of gasification is an ease with which a fuel injected from a fuel injection valve of the internal combustion engine gasifies as a result of a component or components of the fuel, the degree of ease of gasification indicates that the fuel is more unlikely to gasify when the degree of ease of gasification is smaller than the prescribed value than when the degree of ease of gasification is equal to or larger than the prescribed value,
the electronic control unit is configured to set the angle command value more advanced than the retarded angle on a condition that the degree of ease of gasification based on the degree-of-ease information is smaller than the prescribed value, and
the electronic control unit is configured to set the angle command value to the retarded angle on a condition that the degree of ease of gasification based on the degree-of-ease information is equal to or larger than the prescribed value.

4. The ignition timing control apparatus according to claim 3 , wherein
the electronic control unit is configured to set the angle command value more advanced than the retarded angle in response to the degree of ease of gasification based on the degree-of-ease information being smaller than the prescribed value and a temperature of a coolant in the internal combustion engine is lower than a predetermined temperature, and
the electronic control unit is configured to set the angle command value to the retarded angle on a condition that the temperature of the coolant is equal to or higher than the predetermined temperature even when the degree of ease of gasification is smaller than the prescribed value.

5. The ignition timing control apparatus according to claim 2 , wherein
the electronic control unit is configured to make an amount of advancement with respect to the top dead center larger based on a rotational speed of the crankshaft being high than the rotational speed of the crankshaft being low, in response to the electronic control unit setting the angle command value more advanced than the retarded angle.

6. The ignition timing control apparatus according to claim 3 , wherein
the electronic control unit is configured to determine that start of the internal combustion engine is completed in response to a rotational speed of the crankshaft becoming equal to or higher than a predetermined rotational speed,
the electronic control unit is configured to refrain from executing a process of changing the angle command value to the more retarded value as a result of a determination that is made by the electronic control unit that a misfire has occurred, in response to the rotational speed of the crankshaft being equal to or higher than a threshold speed, and
the threshold speed is lower than the predetermined rotational speed.

7. The ignition timing control apparatus according to claim 1 , wherein
the detection timings include an advanced detection timing as the detection timing corresponding to the detected portion that is more advanced than the reference angle by a prescribed angular interval, and
the electronic control unit is configured to calculate a product of an instantaneous rotation time and a quotient as the delay time, the instantaneous rotation time is a time interval from the advanced detection timing to the reference timing, the quotient is a value obtained by dividing an angular interval between the angular command value and the reference angle by the prescribed angular interval.

8. The ignition timing control apparatus according to claim 1 , wherein
the electronic control unit is configured to determine whether or not a misfire has occurred, based on a difference between an average rotational speed of the crankshaft in a first predetermined angular range and an average rotational speed of the crankshaft in a second predetermined angular range,
the first predetermined angular range is an angular range where the rotational speed of the crankshaft is assumed to rise in connection with discharge of the ignition device in a cylinder subjected to a determination on occurrence of a misfire, based on a detected value of a rotational angle of the crankshaft of the internal combustion engine, and
the second predetermined angular range is an angular range before the rotational speed of the crankshaft is assumed to rise.

Assignees

• Toyota Motor Co Ltd

Inventors

• Takei Takuya

Classifications

• F02P7/06

  of circuit-makers or -breakers, or pick-up devices adapted to sense particular points of the timing cycle · CPC title

• Y02T10/46

  Cross-Sectional Technologies · mapped topic

• F02P5/1508

  with particular means during idling · CPC title

• F02P5/1506 Primary

  with particular means during starting · CPC title

• Y02T10/40

  Engine management systems · CPC title