JPH05156996A - Internal combustion engine control device - Google Patents

Abstract

PURPOSE:To prevent a spark advance angle and an abnormal delay angle by optimizing a timing control time. CONSTITUTION:A timing correcting means 43 is provided in order to create error components alpha and alpha' for correcting a control time on the basis of a ratio between a cycle T1 and a reference position clearance TRI', and the error component of the reference position clearance TRI' with respect to an absolute reference position clearance is found out as a correction angle so as to find out a control time Ta' offset in its error component.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an internal combustion engine controller for determining timing control timing (ignition timing, etc.) of each cylinder based on a reference position signal corresponding to a predetermined crank angle,
In particular, the present invention relates to an internal combustion engine control device that optimizes a timing control timing by correcting an error component of a reference position signal with respect to an absolute reference position.

[0002]

2. Description of the Related Art Generally, in an internal combustion engine having a crankshaft driven by a plurality of cylinders and a camshaft interlocked with the crankshafts, timing control timings such as ignition timing and fuel injection timing of each cylinder are determined. A reference position signal that is synchronized with the engine rotation is used. The reference position signal indicates a predetermined reference position corresponding to the crank angle (rotational angle of the crankshaft), and the reference position signal generating means is composed of a rotating plate having a slit corresponding to the reference position, the crankshaft or the camshaft. It is provided in.

FIG. 5 is a functional block diagram showing a conventional internal combustion engine controller. In the figure, reference numeral 1 is a reference position signal generating means composed of a rotating plate provided on a cam shaft,
Predetermined crank angle (θR, θ
The reference position signal Tθ indicating the first and second reference positions corresponding to I) is generated. The reference position signal Tθ is composed of a pulse rising at the first reference position and falling at the second reference position, and its pulse width is, for example, 70 ° in crank angle, and the first reference position is B75 ° (top dead center). 75 ° from the point),
The second reference position indicates B5 °.

Reference numeral 2 is an interface for processing and transmitting the reference position signal Tθ, 3 is various sensors for detecting the operating condition D, and 4 is timing control timing for each cylinder based on the reference position signal Tθ and the operating condition D. For example, it is a microcomputer that calculates the ignition timing.

The microcomputer 4 measures the cycle T1 of the first reference position generation section on the basis of the reference position signal Tθ, and the ignition timing of each cylinder based on the operating condition D and the cycle T1. An ignition timing setting means 42 for generating the control time Ta is provided. The ignition timing setting means 42 constitutes a timing setting means for calculating the ignition timing θA and setting the control time Ta from the first or second reference position to the ignition timing θA.

FIG. 6 shows a reference position signal Tθ corresponding to four cylinders.
FIG. 4 is a waveform diagram showing an example, in which the horizontal axis represents the crank angle θ and the vertical axis represents the pulse intensity of the reference position signal Tθ. In the figure,
The reference position signal Tθ is the first reference position B75 ° for each cylinder.
It rises at and falls at the second reference position B5 °.

In this case, the cycle T of the first reference position generation section for one cylinder is set to 720 ° in crank angle, and the first reference position B75 ° to the next first reference position B7 is set.
The cycle T1 up to 5 ° is set to 180 ° in crank angle. The first and second reference positions correspond to the crank angles θR (= B75 °) and θI (= B5 °), respectively, and the interval TRI between the first and second reference positions is the crank angle.
It is 70 °. The first reference position B75 ° corresponds to the energization timing at startup, and the second reference position B5 ° corresponds to the ignition timing at startup.

FIG. 7 is an explanatory diagram showing the ignition timing θA and its control time Ta1 when the ignition timing is controlled to the advanced side from the second reference position B5 ° during high speed operation.
The reference position B75 ° is the reference for the control time Ta1. FIG. 8 is an explanatory diagram showing the ignition timing θA and its control time Ta2 when the ignition timing is controlled to the retard side from the second reference position B5 ° during low speed operation. In this case, the second reference position B5 ° is It serves as a reference for the control time Ta2.

Next, the operation of the conventional internal combustion engine controller shown in FIG. 5 will be described with reference to FIGS. 6 to 8. The reference position signal Tθ generated as shown in FIG. 6 from the reference position signal generating means 1 in synchronization with the engine rotation is input to the microcomputer 4 via the interface 2.
The cycle measuring means 41 in the microcomputer 4 measures the cycle T1 (the time corresponding to the crank angle of 180 °) based on the reference position signal Tθ, and the ignition timing setting means 42 uses the operating condition D and the cycle T1. Then, the control time Ta is obtained.

That is, if the engine speed is high, the target ignition timing θA is controlled to the advance side as shown in FIG. 7, and if it is low, the ignition timing θA is set to the retard side as shown in FIG. Control. In the case of advance control, the control time Ta at this time is the first
The control time Ta1 is based on the reference position B of 75 ° (= θR)

Ta1 = (θR−θA) T1 / 180 ° ...

[0012] In the case of retard control,
Control time T based on the second reference position B5 ° (= θI)
a2 and θI = θR−70 °,

Ta2 = (θR−70 ° −θA) T1 / 180 ° = (θI−θA) T1 / 180 ° ...

Is calculated from

However, since the reference position signal generating means 1 is limited in manufacturing accuracy and detection capability, each reference position B75 ° and B5 ° of the reference position signal Tθ contains an error component of about ± 2 °. The ignition timing θA calculated by the ignition timing setting means 42 contains an error component within ± 2 ° when converted from the optimum value to the crank angle θ.

On the other hand, the output torque of the internal combustion engine is the maximum torque when the ignition timing θA is the optimum value, whereas it decreases by about 1 horsepower only when the ignition timing θA differs by 1 °. Therefore, even an error component of about ± 2 ° cannot be ignored, and it is an important requirement to obtain the reference position with high accuracy for effective timing control timing.

[0017]

As described above, the conventional internal combustion engine control system fixes the predetermined crank angles θR and θI on the assumption that the reference position signal Tθ represents an absolute reference position, and fixes each reference position. Ignition timing θ based on the cycle T1 between
The timing control timing such as A is set. Therefore, even if the width of the crank angle θ fluctuates due to variations in the reference position detector in the reference position signal generating means 1 and differences among cylinders, and an error component occurs in the reference position, this cannot be corrected, An error component also occurs in the control time Ta. As a result, there is a problem that excessive advancement or abnormal retardation occurs, which causes knocking or insufficient output.

The present invention has been made to solve the above problems, and an object thereof is to obtain an internal combustion engine control device in which the timing control timing is optimized to prevent an over-advanced angle or an abnormal retarded angle. ..

[0019]

According to a first aspect of the present invention, an internal combustion engine control apparatus has an error component for correcting the control time based on the ratio of the cycle and the interval between the first and second reference positions. Is provided with a timing correction means.

Further, in the internal combustion engine control device according to the second aspect of the present invention, the timing correction means is provided with an averaging processing means for averaging the error components obtained in real time.

Further, in the internal combustion engine controller according to claim 3 of the present invention, the operating condition determining means is provided in the timing correcting means, and the error component is obtained under a predetermined operating condition.

Further, in the internal combustion engine controller according to claim 4 of the present invention, the timing correction means is provided with the error component determination means for determining that the error component is within the allowable range, and the error component exceeds the allowable range. Sometimes, the upper limit value or the lower limit value of the allowable range is set as an error component.

[0023]

According to the first aspect of the present invention, the error component of the interval between the reference positions with respect to the interval between the absolute reference positions is obtained as a correction angle, and the control time is corrected so that the error component is offset.

Further, according to the second aspect of the present invention, the error component is obtained by averaging, and the correction accuracy of the control time is improved.

According to the third aspect of the present invention, the error component is obtained under a predetermined operating condition where the engine rotation is stable, and the correction accuracy of the control time is further improved.

According to the fourth aspect of the present invention, the calculated error component is clipped within an allowable range to prevent excessive correction.

[0027]

【Example】

Example 1. An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a functional block diagram showing an embodiment of the present invention. 4A, 41A and 42A are microcomputers 4,
They correspond to the cycle measuring means 41 and the ignition timing setting means 42, respectively, and 1-3 are the same as those described above.

In this case, the cycle measuring means 41A uses the cycle T1.
Not only that, the interval TRI 'between the reference positions including the error component (hereinafter referred to as the reference position interval) is measured. Further, the ignition timing setting means 42A corrects the control time T so that the ignition timing is controlled to an appropriate ignition timing based on an error component α'described later.
a ′ is generated.

Reference numeral 43 is an ignition timing correction means for generating an error component α'based on the ratio of the period T1 and the reference position interval TRI ', and constitutes a timing correction means for correcting the control time. The ignition timing correction means 43 is an error that becomes valid by the operating condition determination means 44 that determines that the operating condition D is a predetermined operating condition in which the engine rotation is stable, and the determination signal H that indicates that the operating condition D is a predetermined operating condition. The calculation means 45 and the error component α obtained in real time by the error calculation means 45
And an averaging processing means 46 for averaging.

2 and 3 are waveform charts showing the period T1 of the reference position signal Tθ detected in real time, the reference position interval TRI 'and the error component α (converted to crank angle), and the optimized ignition timing θA. And the broken line indicates each reference position θR
And the absolute position of θI. In each figure, the period T1 is assumed to be accurate, and the reference position interval TRI 'is the error component α.
including.

FIG. 2 shows a case where the second reference position B5 ° is fixed to an absolute position and the first reference position B75 ° is corrected.
The control time Ta1 from the rising timing (corresponding to the first reference position B75 °) is corrected to Ta1 '. Also, FIG.
Shows the case where the first reference position B75 ° is fixed to the absolute position and the second reference position B5 ° is corrected, and the control time Ta2 from the fall timing (corresponding to the second reference position B5 °)
Has been corrected to Ta2 '.

Next, the operation of the embodiment of the present invention shown in FIG. 1 will be described with reference to the waveform diagrams of FIGS. 2 and 3 and the flowchart of FIG. First, when the reference position signal Tθ is input to the microcomputer 4A via the interface 2, the period measuring means 41A measures the period T1 of the reference position signal Tθ and the reference position interval TRI '.
(Step S1). At this time, the reference position interval TRI 'is as shown in FIG.
Alternatively, as shown in FIG. 3, the crank angle conversion error component α is included.

As the cycle T1, the time measured in the generation section of the first reference position B75 ° for the two cylinders is used, but the cycle of the first reference position B75 ° for the specific cylinder (crank angle 720) It is also possible to use a time obtained by measuring (corresponding to °) and multiplying by 1/4. Further, the measurement time of the cycle T1 may be averaged.

Subsequently, the operating condition judging means 44 in the ignition timing correcting means 43 judges whether the operating condition D is a predetermined operating condition (step S2).
Is output. The engine operating speed is 2000 as a predetermined operating condition.
Stable operation below rpm is selected.

In response to the judgment signal H from the operating condition judging means 44, the error calculating means 45 determines, based on the ratio between the reference position interval TRI 'and the period T1.

Α = (TRI ′ / T1) × 180 ° −70 ° = [TRI ′ × (180 ° / 70 °) −T1] × (70 ° / T1) ...

Then, the error component α corresponding to the correction angle is calculated (step S3). In the formula, (70 ° / T1) corresponds to a term for converting the measurement time into a crank angle, but in practice, in order to minimize the calculation error, a constant that is uniquely determined from the rotation speed information of the operating condition D. Is used. For example, when the engine speed is 2000 rpm, the data value stored in advance in the microcomputer 4A, that is, (1/256) × (1 /
214) is used.

Next, the averaging means 46 averages the error component α obtained in real time according to the equation.
(Step S4), the error component α'after the averaging process is input to the ignition timing setting means 42A. For example, if the error component calculated this time is αn and the error component calculated last time is αn _-1 ,
The error component α ′ after the averaging process is

Α '= (αn _-1 + αn) / 2 ...

It is calculated from Needless to say, the plurality of error components αi to be subjected to the averaging process relate to the same specific cylinder. Further, in the case of the formula, the number of data used for averaging is two, but the number of data can be arbitrarily increased as needed.

Finally, the ignition timing setting means 42A controls the control time T which accurately corresponds to the ignition timing θA based on the operating condition D, the cycle T1 of the reference position signal Tθ and the error component α '.
a'is calculated (step S5). That is, as shown in FIG.
When the reference position B of 75 ° is corrected, the first reference position B
The control time Ta1 from 75 ° is corrected by the error component, and the corrected control time Ta1 ′ is

Ta1 ′ = (θR + α′−θA) T1 / 180 ° ...

Calculated from As a result, the ignition timing θA for cutting off the coil current is optimized by offsetting the error component α, and an accurate control time Ta1 ′ is set for the ignition timing θA during the advance control. Note that, in FIG. 2, when the ignition timing θA is retarded control, the second reference position B5 ° is regarded as accurate, so it is not necessary to correct the control time Ta2.

Further, as shown in FIG. 3, the second reference position B5 °
Is corrected, the control time Ta2 from the second reference position B5 ° is corrected by the error component, and the corrected control time Ta2 ′ is obtained.
To

Ta2 ′ = (θR−70 ° −α′−θA) T1 / 180 ° = (θI−α′−θA) T1 / 180 ° ...

Calculated from As a result, as in the case of FIG. 2, the error component α is canceled out, the control time Ta2 ′ is optimized, and the ignition timing θA during the retard control is set accurately.
Further, during the advance angle control, the first reference position B75 ° is regarded as accurate, so it is not necessary to correct the control time Ta1. On the other hand, in step S2, when it is determined that the operating condition D is not the predetermined operating condition, the process proceeds to step S5, and the control time before correction or the control time Ta ′ based on the previously obtained error component is calculated. To be done.

By the control time Ta 'thus calculated, the error component α is canceled out, and the optimized ignition timing θA
At, actual ignition control is performed. The error component α ′ is
It is needless to say that it is used as a correction angle even under operating conditions where the engine speed is 2000 rpm or more. Therefore, the ignition timing θA is prevented from being excessively advanced or abnormally retarded, and knocking or the like will not occur. Such correction of the timing control timing can also be applied to the fuel injection timing of each cylinder, and has the same effect.

Example 2. Although the ignition timing setting means 42A corrects the control time Ta by using the error component α'after the averaging process in the above embodiment, it may be corrected by using the error component α obtained in real time.

Example 3. Further, although the operation condition determination means 44 is used to calculate the error component α under a predetermined operation condition, it may be calculated under any operation condition.

Example 4. Further, the error component α'obtained by the ignition timing correction means 43 is used as it is as the correction angle,
The ignition timing correction means 43 is provided with an error component determination means (not shown) for determining whether or not the calculated error component α or α'is within the allowable range, and the absolute value of the error component α or α'is allowed. When exceeding the range, the error component may be clipped within the allowable range.

That is, since the error contained in each reference position B75 ° or B5 ° is about ± 2 ° as described above, when the absolute value of the error component α or α'exceeds 2 °, it remains as it is. If you use it for the correction angle, it will be excessive correction, so
The upper limit of 2 ° or the lower limit of −2 ° of the allowable range is set as an error component to prevent excessive correction.

[0052]

As described above, according to the first aspect of the present invention, the timing correction means for generating the error component for correcting the control time based on the ratio of the cycle and the reference position interval is provided, and the absolute reference is provided. Since the error component of the reference position interval with respect to the position interval is calculated as the correction angle and the control time that cancels the error component is calculated, the timing control timing is optimized to prevent overadvance and abnormal retardation. There is an effect that can be obtained.

According to the second aspect of the present invention, the timing correction means is provided with an averaging processing means for averaging the error component obtained in real time, and the control time is based on the error component after the averaging processing. Since I tried to correct
There is an effect that an internal combustion engine control device with improved control time correction accuracy can be obtained.

Further, according to the third aspect of the present invention, the timing correction means is provided with the operating condition determining means, and the error component is obtained only under a predetermined operating condition in which the engine rotation is stable, so that the control time is corrected. There is an effect that an internal combustion engine control device with further improved accuracy can be obtained.

According to the fourth aspect of the present invention, the timing correction means is provided with error component determination means for determining that the error component is within the allowable range, and when the allowable range is exceeded, the upper limit value or the lower limit value is set. Since it is set as an error component, there is an effect that an internal combustion engine control device that prevents excessive correction can be obtained.

[Brief description of drawings]

FIG. 1 is a functional block diagram showing an embodiment of the present invention.

FIG. 2 is a waveform diagram showing a reference position signal in one embodiment of the present invention.

FIG. 3 is a waveform diagram showing a reference position signal in one embodiment of the present invention.

FIG. 4 is a flowchart showing the operation of the embodiment of the present invention.

FIG. 5 is a functional block diagram showing a conventional internal combustion engine controller.

FIG. 6 is a waveform diagram showing a general reference position signal.

FIG. 7 is a waveform diagram showing a general reference position signal and ignition timing.

FIG. 8 is a waveform diagram showing a general reference position signal and ignition timing.

[Explanation of symbols]

 1 Reference position signal generating means 41A Cycle measuring means 42A Ignition timing setting means (timing setting means) 43 Ignition timing correcting means (timing correcting means) 44 Operating condition judging means 46 Averaging processing means D Operating condition Tθ Reference position signal T1 cycle TRI ′ Reference position interval Ta ′, Ta1 ′, Ta2 ′ Control time α, α ′ Error component θA Ignition timing (timing control timing) θR, B75 ° First reference position θI, B5 ° Second reference position

[Procedure amendment]

[Submission date] July 30, 1992

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] 0037

[Correction method] Change

[Correction content]

Then, the error component α corresponding to the correction angle is calculated (step S3). In the formula, (70 ° / T1) corresponds to the term for converting the measurement time into the crank angle, but in actuality, in order to make the calculation process fast and easy and to minimize the calculation error, the operating condition D A constant that is uniquely determined from the rotation speed information is used. For example, the rotation speed information is Ne, and N
When e is information indicating 256 at 2000 rpm, Ne = (30 × 1
It is represented by 0 ⁶ / T1) × (256/2000). Therefore, using the data value stored in advance in the microcomputer 4A, that is, (1/256) × (1/214), the equation is α = [TRI ′ × (180 ° / 70 °) −T1] XNe x (1/256) x (1/214).

Claims (4)

[Claims] 1. A reference position signal generating means for generating a reference position signal indicating first and second reference positions corresponding to a predetermined crank angle of each cylinder in synchronism with engine rotation, and the first reference position Cycle measuring means for measuring the cycle of the generation section, and calculating the timing control timing of each cylinder based on the operating conditions and the cycle, and controlling time from the first or second reference position to the timing control timing. In an internal combustion engine control device including: a timing setting unit that sets the error, an error component for correcting the control time is calculated based on a ratio between the cycle and the interval between the first and second reference positions. An internal combustion engine control device comprising a timing correction means. 2. The internal combustion engine controller according to claim 1, wherein the timing correction means includes an averaging processing means for averaging the error components obtained in real time. 3. The timing correcting means includes operating condition determining means for determining that the operating condition is a predetermined operating condition in which engine rotation is stable, and determining the error component under the predetermined operating condition. Claim 1 characterized by
Alternatively, the internal combustion engine controller according to claim 2. 4. The timing correction means includes error component determination means for determining that the error component is within an allowable range, and when the error component exceeds the allowable range, an upper limit value or a lower limit of the allowable range. The internal combustion engine control apparatus according to claim 1, 2 or 3, wherein a value is set as the error component.