JPH05312089A - Internal combustion engine controller - Google Patents

Abstract

PURPOSE:To provide an internal combustion engine controller that shortens a span of cylinder discriminating time as well as to enable it to back up any trouble in a cylinder discriminating signal generating means. CONSTITUTION:This controller is provided with an auxiliary cylinder discriminating signal generating means 6 which generates an auxiliary cylinder discriminating signal C2 different in a waveform to each cylinder in relation to a cylinder discriminating signal C. A microcomputer 1A recognizes each cylinder on the basis of a reference position signal T and either of the cylinder discriminating signal C and the auxiliary cylinder discriminating signal C2.

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 control device for controlling fuel injection and ignition timing for each cylinder based on a crank angle reference position, and more particularly to shortening cylinder identification time and generating a cylinder identification signal. The present invention relates to an internal combustion engine control device capable of backing up against a failure of the means.

[0002]

2. Description of the Related Art Generally, in an internal combustion engine such as an automobile engine, it is necessary to optimally control fuel injection and ignition timing according to operating conditions. For this reason, a microcomputer is used that recognizes the crank angle reference position for each cylinder, calculates the ignition timing, and controls the timer.

FIG. 8 is a block diagram showing a conventional internal combustion engine controller. In the figure, reference numeral 1 denotes a microcomputer, which calculates an ignition timing of each cylinder based on a reference position signal T and a cylinder identification signal C, and outputs a control signal S corresponding thereto.

Reference numeral 2 is a reference position signal generating means for generating a reference position signal T, and 3 is a cylinder identification signal generating means for generating a cylinder identification signal C. As is well known, these are provided on a crankshaft or a camshaft. It is composed of a rotary slit, a photo coupler, and the like. Reference numerals 4 and 5 perform waveform processing of the reference position signal T and the cylinder identification signal C, and the microcomputer 1
Is an interface circuit for input to.

FIG. 9 shows a reference position signal T and a cylinder identification signal C.
3 is a timing chart showing pulse waveforms of the above, where the number of control target cylinders is 6 cylinders (# 1 to # 6). The reference position signal T is B75 ° (TDC
The crank angle (CA) 75 ° before) is set as the reference reference position (ref), and the crank angle B5 ° (5 ° before TDC) is set as the initial reference position (ini). It is a pulse waveform that rises at.

Therefore, when converted into crank angle (CA),
The total cycle of the reference position signal T for 6 cylinders is 720 °, and the cycle between the cylinders is 120 °. Further, the pulse width from the reference reference position ref (B75 °) to the initial reference position ini (B5 °) for one cylinder is 70 °, and the reference reference position ini (B5 °) of a certain cylinder to the reference reference of the next cylinder. Pulse width up to position ref (B75 °) is 50
°.

On the other hand, the cylinder identification signal C indicates the reference position B5.
In order to obtain a combination of different level signals for each cylinder at .degree. FIG. 10 is an explanatory view showing the cylinder identification operation,
ini (n-1) is an initial reference position corresponding to the cylinder before the identification target cylinder, and ref (n) is a reference reference position corresponding to the identification target cylinder. In this case, ini (n
-1) and ref (n) indicate that each cylinder is identified based on the level (0 or 1) of the pair of cylinder identification signals C at each edge.

Next, referring to FIG. 9 and FIG.
The operation of the conventional internal combustion engine controller shown in FIG. First, when the engine rotates, the reference position signal generating means 2
Generates a reference position signal T composed of pulses corresponding to the reference positions B75 ° and B5 ° of each cylinder as shown in FIG. 9, and inputs it to the microcomputer 1 via the interface circuit 4. Similarly, the cylinder identification signal generating means 3 generates a cylinder identification signal C capable of identifying a specific cylinder as shown in FIG.
Input to the microcomputer 1 via the interface circuit 5.

Based on the reference position signal T and the cylinder identification signal C obtained in synchronism with the rotation of the engine, the microcomputer 1 recognizes the cylinders and the reference positions for the cylinders, and determines the operating condition according to the operating conditions. The control timing such as the ignition timing is calculated, and the control signal S corresponding to the calculation result is output. For example, when the ignition timing control is on the retard side, timer control based on the reference reference position B75 ° is performed,
On the advance side, timer control is performed based on the initial reference position B5 °.

At this time, the microcomputer 1
As in 10, the level of the cylinder identification signal C at each reference position is read, and a specific cylinder is detected by this level pair to identify the cylinder. That is, if the level pair of the cylinder identification signal C is "1, 1", the latter reference reference position re
Recognizing that f (n) corresponds to the second cylinder (# 2),
If it is "1, 0", the latter reference reference position re
It is recognized that f (n) corresponds to the fifth cylinder (# 5). This makes it possible to generate an appropriate control signal S for each cylinder.

However, when the level pair of the cylinder identification signal C is "0, 0" or "0, 1", two cylinder groups (# 1 and # 4 or # 3 and # 6) are recognized. You can, but you can't immediately identify the cylinder. Therefore, if the timing of the cylinder identification processing is good, from ini (n-1)
Cylinder identification is possible in the time corresponding to a crank angle of 50 ° up to ref (n), but if the timing is incorrect, cylinder identification will be performed until the reference position (B75 °) corresponding to # 2 cylinder or # 5 cylinder is reached. Does not complete. That is, in the worst case, the entire cycle (720
Cylinder identification is required for a time corresponding to a crank angle of 360 °, which is half of (°).

[0012]

As described above, the conventional internal combustion engine control device has the reference position signal T and the cylinder identification signal C.
Since the cylinders are identified based on only the above, there is a problem that it takes a long time to identify the cylinders when the timing is worst. Further, when an error occurs in the cylinder identification signal C due to a failure of the cylinder identification signal generating means 3, there is a problem that the cylinder cannot be identified at all because there is no backup means.

The present invention has been made to solve the above-mentioned problems, and provides an internal combustion engine control device that shortens the cylinder identification time and can back up against a failure of the cylinder identification signal generating means. The purpose is to

[0014]

An internal combustion engine control apparatus according to the present invention is provided with an auxiliary cylinder identification signal generating means for generating an auxiliary cylinder identification signal having a different waveform for each cylinder in relation to the cylinder identification signal. The computer recognizes each cylinder based on the reference position signal and at least one of the cylinder identification signal and the auxiliary cylinder identification signal.

[0015]

According to the present invention, each cylinder is identified based on the level of at least one of the cylinder identification signal and the auxiliary cylinder identification signal at the reference position.

[0016]

【Example】

Example 1. Embodiment 1 of the present invention will be described below with reference to the drawings. First Embodiment FIG. 1 is a block diagram showing a first embodiment of the present invention. 1A corresponds to a microcomputer 1,
5 is the same as described above.

Reference numeral 6 denotes an auxiliary cylinder identification signal generating means different from the cylinder identification signal generating means 3, and the cylinder identification signal generating means 3
The auxiliary cylinder identification signal C2 having a waveform similar to that of the cylinder identification signal C and having a different waveform is generated for each cylinder. Reference numeral 7 is an interface circuit for waveform-processing the auxiliary cylinder identification signal C2 from the auxiliary cylinder identification signal generating means 6 and inputting it to the microcomputer 1A. In this case, the microcomputer 1A recognizes the specific cylinder and each cylinder based on the reference position signal T and at least one of the cylinder identification signal C and the auxiliary cylinder identification signal C2.

FIG. 2 is a timing chart showing pulse waveforms of the reference position signal T, the cylinder identification signal C and the auxiliary cylinder identification signal C2. In this case, the auxiliary cylinder identification signal C2 is # 3.
The level becomes 1 level in the section including the cylinder initial reference position B5 ° to the # 6 cylinder reference reference position B75 °. This makes it possible to generate levels corresponding to cylinders # 4 to # 6, as will be described later.

FIG. 3 is an explanatory view showing the cylinder identifying operation.
Compared with the conventional example of FIG. 10, the reference reference position ref
The level of the auxiliary cylinder identification signal C2 in (n) is newly added and used for cylinder identification.

Next, referring to FIGS. 2 and 3, FIG.
The operation of the first embodiment of the present invention shown in FIG.
First, as the engine rotates, the reference position signal generation means 2, the cylinder identification signal generation means 3, and the auxiliary cylinder identification signal generation means 6 are generated.
Generates a reference position signal T, a cylinder identification signal C and an auxiliary cylinder identification signal C2 as shown in FIG. 2, and the microcomputer 1 via the interface circuits 4, 5 and 7, respectively.
To enter.

Here, the auxiliary cylinder identification signal C2 rises in synchronization with the falling timing of the cylinder identification signal C corresponding to the # 3 cylinder, and the cylinder identification signal C corresponding to the # 6 cylinder.
It falls in synchronization with the falling timing of.

As described above, the reference position signal T, the cylinder identification signal C and the auxiliary cylinder identification signal obtained in synchronization with the rotation of the engine.
Based on C2, the microcomputer 1A recognizes each cylinder and a reference position for each cylinder, calculates a control timing such as ignition timing according to an operating state, and outputs a control signal S corresponding to the calculation result.

That is, as shown in FIG. 3, the microcomputer 1A sets the level of the cylinder identification signal C at the initial reference position ini (n-1) corresponding to B5 ° of the front cylinder and the B75 ° of the cylinder to be identified. The levels of the cylinder identification signal C and the auxiliary cylinder identification signal C2 at the corresponding reference reference position ref (n) are read, and the cylinders # 1 to # 6 are identified by their combination.

That is, the combination of levels is "0, 0,
If “0”, the reference reference position ref (n) is # 1.
Recognizing that it corresponds to the cylinder, the same applies to "1,
If it is "1, 0" (only "1, 1" can be identified), then # 2
Cylinder, if it is "0, 1, 0", it is # 3 cylinder, "0, 0,
1 "corresponds to the # 4 cylinder," 1,0,1 "(only" 1,0 "can be identified) corresponds to the # 5 cylinder, and" 0,1,1 "corresponds to the # 6 cylinder. Recognize that you are doing.

As a result, the cylinders # 1 to # 6 can be identified in a short time, and the appropriate control signal S for that cylinder can be immediately generated. For example, the initial reference position in
If level reading is started from the best timing immediately before i (n-1), then ini (n-1) will start at ref.
The cylinder can be identified in a time corresponding to a crank angle of 50 ° up to (n). Even if the level reading is started from the worst timing immediately after the initial reference position ini (n-1), the next ini (n
-1) to ref (n) plus 50 ° crank angle 170 °
The cylinder can be identified in a time corresponding to.

Therefore, even at the time of starting, the optimum control signal S based on the cylinder identification can be obtained in a short time, and highly reliable operation control can be performed. Even if one of the cylinder identification signal generating means 3 and the auxiliary cylinder identification signal generating means 6 fails and the cylinder identification signal C or the auxiliary cylinder identification signal C2 is no longer obtained, at least one of them is sound. If so, the cylinder identification capability does not decrease, and reliable control can be continued.

Example 2. In the above embodiment, the cylinder identification signal C has a pulse waveform as in the conventional case and the auxiliary cylinder identification signal C2 is added. However, if the combination of the cylinder identification signal and the auxiliary cylinder identification signal can be related to each cylinder, Each may have another pulse waveform.

FIG. 4 is a waveform diagram showing the cylinder identification signal C1 and the auxiliary cylinder identification signal C2a according to the second embodiment. In this case,
The cylinder identification signal C1 acts as a first cylinder identification signal, and the auxiliary cylinder identification signal C2a acts as a second cylinder identification signal. The cylinder identification signal C1 is B75 ° of # 3 cylinder to B5 ° of # 4 cylinder, and B5 ° of # 5 cylinder to B75 ° of # 6 cylinder.
It is one level in the range including. Also, the auxiliary cylinder identification signal C2
a is B5 ° of the # 1 cylinder to B5 ° of the # 2 cylinder, and
The level is 1 in a range including B75 of the # 4 cylinder to B5 of the # 5 cylinder.

FIG. 5 is an explanatory diagram showing a cylinder identifying operation according to the second embodiment. As with the first embodiment, the level of the cylinder identifying signal C1 at the initial reference position ini (n-1) of the preceding cylinder and the level of the cylinder identifying signal C1 are shown. Reference reference position ref of the cylinder to be identified
Cylinder identification can be completed in a short time based on the combination of the levels of the cylinder identification signal C1 and the auxiliary cylinder identification signal C2a in (n).

Further, in the case of simultaneous ignition control for every two cylinders,
The group can be identified only by the levels of the cylinder identification signal C1 and the auxiliary cylinder identification signal C2a at the reference reference position ref (n). For example, in the case of "0, 0" or "1, 1", the # 1 and # 4 cylinders, in the case of "0, 1" the # 2 and # 5 cylinders, and in the case of "1, 0", the # 3 cylinder. And, the simultaneous ignition control of the # 6 cylinder is performed. Therefore, even if the group identification timing is the worst, the identification can be performed within the time corresponding to the crank angle of 120 °.

Example 3. Further, the case where the number of control cylinders is 6 is shown, but an internal combustion engine having another number of cylinders may be a control target. FIG. 6 shows the reference position signal Tb, the cylinder identification signal C1b, and the auxiliary cylinder identification signal C2b in the case of four cylinders according to the third embodiment.
7 is a waveform diagram showing each pulse waveform of FIG. 7, and FIG. 7 is an explanatory diagram showing a cylinder identifying operation according to the third embodiment.

In this case, the reference position signal Tb rises at the reference reference position ref of B75 ° and falls at the initial reference position ini of B5 ° for each cylinder.
Further, the cylinder identification signal C1b is one level in a range including B75 ° of the # 1 cylinder to B5 ° of the # 3 cylinder, and the auxiliary cylinder identification signal C2b is a range including B75 ° to B5 ° of the # 1 cylinder, In addition, the level is 1 in the range including B75 of the # 4 cylinder.

The cylinders # 1 to # 4 are identified based on the levels of the cylinder identification signal C1b and the auxiliary cylinder identification signal C2b at the reference reference position ref (n) as shown in FIG. That is, if the level pair is "1, 1", it is # 1 cylinder, if it is "1, 0", it is # 3 cylinder, if it is "0, 1", it is # 4 cylinder, and if it is "0, 0", it is #. It is identified as two cylinders.
Therefore, even if the cylinder identification start timing is the worst, cylinder identification is completed within the time corresponding to 180 ° of the crank angle cycle of one cylinder.

[0034]

As described above, according to the present invention, auxiliary cylinder identification signal generating means for generating an auxiliary cylinder identification signal having a different waveform for each cylinder in relation to the cylinder identification signal is provided, and the microcomputer is configured to operate as a reference. Since each cylinder is recognized based on the position signal and at least one of the cylinder identification signal and the auxiliary cylinder identification signal, the cylinder identification time can be shortened and the cylinder identification signal generating means can be backed up in case of failure. There is an effect that the internal combustion engine control device described above can be obtained.

[Brief description of drawings]

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

FIG. 2 is a waveform diagram showing each signal generated in the first embodiment of the present invention.

FIG. 3 is an explanatory diagram showing a cylinder identifying operation according to the first embodiment of the present invention.

FIG. 4 is a block diagram showing each signal generated in the second embodiment of the present invention.

FIG. 5 is an explanatory diagram showing a cylinder identifying operation according to the second embodiment of the present invention.

FIG. 6 is a waveform diagram showing each signal generated in the third embodiment of the present invention.

FIG. 7 is an explanatory diagram showing a cylinder identifying operation according to the third embodiment of the present invention.

FIG. 8 is a block diagram showing a conventional internal combustion engine controller.

FIG. 9 is a waveform diagram showing each signal generated in the conventional internal combustion engine control device.

FIG. 10 is an explanatory diagram showing a cylinder identifying operation in a conventional internal combustion engine control device.

[Explanation of symbols]

 1A Microcomputer 2 Reference position signal generating means 3 Cylinder identification signal generating means 6 Auxiliary cylinder identification signal generating means T, Tb Reference position signal B5 °, B75 ° Reference position C, C1, C1b Cylinder identification signal C2, C2a, C2b Auxiliary cylinder Identification signal S control signal

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[Procedure amendment]

[Submission date] August 6, 1992

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0009

[Correction method] Change

[Correction content]

Based on the reference position signal T and the cylinder identification signal C obtained in synchronism with the rotation of the engine, the microcomputer 1 recognizes the cylinders and the reference positions for the cylinders, and determines the operating condition according to the operating conditions. The control timing such as the ignition timing is calculated, and the control signal S corresponding to the calculation result is output. For example, when the ignition timing control is on the advance side, timer control based on the reference reference position B75 ° is performed,
On the retard side, timer control is performed with reference to the reference reference position B75 ° or the initial reference position B5 °.

[Procedure Amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0020

[Correction method] Change

[Correction content]

Next, referring to FIGS. 2 and 3, FIG.
The operation of the first embodiment of the present invention shown in FIG.
First, as the engine rotates, the reference position signal generation means 2, the cylinder identification signal generation means 3, and the auxiliary cylinder identification signal generation means 6 are generated.
Generates a reference position signal T, a cylinder identification signal C and an auxiliary cylinder identification signal C2 as shown in FIG. 2, and the microcomputer 1 via the interface circuits 4, 5 and 7, respectively.
Enter in A.

Claims (1)

[Claims] 1. A reference position signal generating means for generating a reference position signal corresponding to a predetermined crank angle for each cylinder in synchronism with rotation of an engine, and a cylinder for identifying a specific cylinder in relation to the reference position signal. A cylinder identification signal generating means for generating an identification signal, and a micro for recognizing the reference position of each cylinder based on the reference position signal and the cylinder identification signal and for generating a control signal corresponding to the control timing of each cylinder. An internal combustion engine control device comprising: a computer; and an auxiliary cylinder identification signal generating means for generating an auxiliary cylinder identification signal having a different waveform for each of the cylinders in association with the cylinder identification signal. Recognizing each of the cylinders based on a reference position signal and at least one of the cylinder identification signal and the auxiliary cylinder identification signal. Internal combustion engine control apparatus according to symptoms.