WE CLAIM:
1. A control method for an internal combustion engine comprising:
an intake pressure detection step that detects an intake pressure, which is a pressure of gas in an intake pipe (101a), at a plurality of preliminarily set time points in starting of the internal combustion engine; and
an individual value determination step that determines an individual value (A) used for estimation of a body temperature (Te0) of the internal combustion engine in starting, based on a first pressure (P1) and a second pressure (P2) which are the intake pressures detected respectively at preliminarily set first time point and second time point.
2. The control method for the internal combustion engine according
to claim 1, further comprising:
an outside air temperature detection step that detects an outside air temperature (T0) which is a temperature of outside air taken into the intake pipe (101a);
a rotational speed detection step that detects a rotational speed (Ne4) of the internal combustion engine;
a body temperature estimation step that estimates the body temperature (Te0) in starting, based on the rotational speed (Ne4), the outside air temperature (T0), a third pressure (P3) and a fourth pressure (P4) which are the intake pressures detected respectively at preliminarily set third time point and fourth time point, and the
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individual value (A); and
an engine control step that controls the internal combustion engine based on the body temperature (Te0) in starting.
3. The control method for the internal combustion engine according
to claim 1 or 2,
wherein the individual value determination step determines the individual value (A), based on a pressure difference between the first pressure (P1) and the second pressure (P2).
4. The control method for the internal combustion engine according
to any one of claims 1 to 3, further comprising an outside air
temperature detection step that detects an outside air temperature
(T0) which is a temperature of outside air taken into the intake pipe (101a),
wherein the individual value determination step determines the individual value (A), based on the first pressure (P1), the second pressure (P2), and the outside air temperature (T0).
5. The control method for the internal combustion engine according
to any one of claims 1 to 4, wherein the internal combustion engine
is a four-cycle engine which performs four cycle of an intake stroke,
a compression stroke, an expansion stroke, and an exhaust stroke,
the first time point is a time point of a crank angle which is preliminarily set in first half of the compression stroke in a first
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four-cycle after rotation of a crankshaft starts, and
the second time point is a time point of a crank angle which is preliminarily set in the compression stroke after the first time point in the first four-cycle.
6. The control method for the internal combustion engine according
to any one of claims 1 to 4, wherein the internal combustion engine
is a four-cycle engine which performs four cycle of an intake stroke,
a compression stroke, an expansion stroke, and an exhaust stroke,
the first time point is a time point before rotation of a crankshaft starts, and
the second time point is a time point of a crank angle which is preliminarily set in second half of the compression stroke in a first four-cycle after rotation of the crankshaft starts.
7. The control method for the internal combustion engine according
to any one of claims 1 to 4, wherein the internal combustion engine
is a four-cycle engine which performs four cycle of an intake stroke,
a compression stroke, an expansion stroke, and an exhaust stroke,
the first time point is a time point of a crank angle which is preliminarily set in first half of the compression stroke in a first four-cycle after rotation of a crankshaft starts, and
the second time point is a time point of a crank angle which is preliminarily set in first half of the expansion stroke after the first time point in the first four-cycle.
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8. The control method for the internal combustion engine according
to any one of claims 1 to 7, wherein the internal combustion engine
is a four-cycle engine which performs four cycle of an intake stroke,
a compression stroke, an expansion stroke, and an exhaust stroke;
and
when a fifth pressure (P5), which is the intake pressure detected at a fifth time point of a crank angle which is preliminarily set in the compression stroke or the expansion stroke in a first four-cycle after rotation of a crankshaft starts, is higher than a preliminarily set determination pressure, the individual value determination step determines the individual value (A), based on the first pressure (P1) and the second pressure (P2) detected at the first time point and the second time point in a next four-cycle, or the second pressure (P2) detected at the second time point in the next four-cycle.
9. The control method for the internal combustion engine according
to claim 2, wherein the body temperature estimation step sets the
body temperature (Te0) in starting to Te0, sets the rotational speed
(Ne4) to Ne, sets the outside air temperature (T0) to T0, sets the
third pressure (P3) to P3, sets the fourth pressure (P4) to P4, sets
the individual value (A) to A, respectively sets preliminarily set
four constants to B, C, D, E, and estimates the body temperature (Te0)
in starting by a calculation equation of "Te0 = A × (P4 / P3 - B)C
× T0D × NeE".
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10. The control method for the internal combustion engine according
to claim 2 or 9, wherein the internal combustion engine is a four-cycle
engine which performs four cycle of an intake stroke, a compression
stroke, an expansion stroke, and an exhaust stroke;
the third time point is a time point before rotation of a crankshaft starts; and
the fourth time point is a time point of a crank angle which is preliminarily set in first half of the compression stroke or the expansion stroke in a first four-cycle after rotation of the crankshaft starts.
11. The control method for the internal combustion engine according to any one of claims 2, 9 and 10, wherein the body temperature estimation step sets the body temperature (Te0) in starting to an initial value, and estimates the body temperature based on energy balance, after combustion starts.
12. The control method for the internal combustion engine according to claim 2, wherein the engine control step changes a fuel injection amount in starting, based on the body temperature (Te0) in starting.
13. A controller for an internal combustion engine comprising:
an intake pressure detection unit (51) that detects an intake pressure, which is a pressure of gas in an intake pipe (101a), at
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a plurality of preliminarily set time points in starting of an internal combustion engine; and
an individual value determination unit (54) that determines an individual value (A) used for estimation of a body temperature (Te0) of the internal combustion engine in starting, based on a first pressure (P1) and a second pressure (P2) which are the intake pressures detected respectively at preliminarily set first time point and second time point.
14. A controller for an internal combustion engine comprising:
an intake pressure detection unit (51) that detects an intake pressure, which is a pressure of gas in an intake pipe (101a), at a plurality of preliminarily set time points in starting of an internal combustion engine;
an outside air temperature detection unit (53) that detects an outside air temperature (T0) which is a temperature of outside air taken into the intake pipe (101a);
an individual value determination unit (54) that determines an individual value (A) used for estimation of a body temperature (Te0) of the internal combustion engine in starting, based on a first pressure (P1) and a second pressure (P2) which are the intake pressures detected respectively at preliminarily set first time point and second time point;
a rotational speed detection unit (52) that detects a rotational speed (Ne4) of the internal combustion engine;
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a body temperature estimation unit (55) that estimates the body temperature (Te0) in starting, based on the rotational speed (Ne4), the outside air temperature (T0), a third pressure (P3) and a fourth pressure (P4) which are the intake pressures detected respectively at preliminarily set third time point and fourth time point, and the individual value (A); and
an engine control unit (56) that controls the internal combustion engine based on the body temperature (Te0) in starting.
Dated this 28 day of February 2019
~Digitally signed~
Arindam Paul
REG.NO:IN/PA-174
of De Penning & De Penning
Agent for the Applicants
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