JPH06346779A - Misfire detecting device for internal combustion engine - Google Patents

Misfire detecting device for internal combustion engine

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Publication number
JPH06346779A
JPH06346779A JP16601193A JP16601193A JPH06346779A JP H06346779 A JPH06346779 A JP H06346779A JP 16601193 A JP16601193 A JP 16601193A JP 16601193 A JP16601193 A JP 16601193A JP H06346779 A JPH06346779 A JP H06346779A
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JP
Japan
Prior art keywords
misfire
crank angle
angular velocity
angle plate
angular speed
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
JP16601193A
Other languages
Japanese (ja)
Other versions
JP3057962B2 (en
Inventor
Katsuhiko Toyoda
克彦 豊田
Original Assignee
Suzuki Motor Corp
スズキ株式会社
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Suzuki Motor Corp, スズキ株式会社 filed Critical Suzuki Motor Corp
Priority to JP5166011A priority Critical patent/JP3057962B2/en
Publication of JPH06346779A publication Critical patent/JPH06346779A/en
Application granted granted Critical
Publication of JP3057962B2 publication Critical patent/JP3057962B2/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

Links

Abstract

PURPOSE:To eliminate influence of the work tolerance of a crank angle plate on an angular speed by measuring the angular speed per misfire detector at the time of deceleration of an engine, and memorizing the measured valve as a correction value, and then making corrective control of the angular speed at the time of misfire detection according to the correction value. CONSTITUTION:A crank angle plate 4 is mounted on the end part of a crank shaft 2 in an internal combustion engine. A plurality of misfire detectors 6 are arranged on the outer circumference of the crank angle plate 4. The angular speed of each misfire detector 6 is detected by an electromagnetic pick up 10. Misfire condition is judged by a control unit 8 on the basis of change of the angular speed. In this case, in the control unit 8, the angular speed is measured per misfire detector 6 at the time of deceleration of the internal combustion engine, and the measured value is memorized as a correction value. The angular speed at the time of misfire detection is corrected and controlled according to the correction value. It is thus possible to eliminate any influence on the angular speed caused by a work tolerance of the crank angle plate 4 so as to improve accuracy of misfire detection.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a misfire detecting device for an internal combustion engine, and more particularly to a crankshaft having a crank angle plate mounted thereon, and a plurality of misfire detectors provided on the outer periphery of the crank angle plate. The present invention relates to a misfire detection device for an internal combustion engine, which measures the angular velocity of the engine and detects a misfire state by a change in the angular velocity of a misfire detector.

[0002]

2. Description of the Related Art In an internal combustion engine of a vehicle, a lean air-fuel mixture is operated to perform so-called lean combustion,
Some reduce the generation of harmful components in exhaust gas and improve fuel efficiency.

However, if the air-fuel mixture is too thin, the combustion in the combustion chamber may become poor, and unburned gas may flow to the exhaust system side to cause misfire. The generated misfire is a factor that causes functional deterioration and damage of the catalyst body and the like.Therefore, a fuse sensor is installed on the downstream side of the catalyst body, and the temperature of the catalyst body exceeds a preset value due to misfire, and this fuse sensor When the temperature condition is detected, it is displayed on the meter or a warning lamp is turned on on the panel to notify the driver of the occurrence of misfire.

An example of the misfire detecting device for the internal combustion engine is disclosed in Japanese Patent Laid-Open No. 2-49955. The cylinder abnormality detection device for an internal combustion engine disclosed in this publication can accurately detect a cylinder abnormality that causes a misfire. That is, in the first device, when the rotational angular velocity of the output shaft of the internal combustion engine is lower than the angular velocity reference value,
When the angular velocity reference value for the next cylinder is changed to a value that is larger than the normal update value, and when an irregular misfire etc. occurs in another cylinder,
Abnormal cylinders are detected quickly and reliably. Further, in the second device, an abnormal cylinder is detected based on the relationship between the number of times the rotational angular velocity of the predetermined cylinder is determined to be smaller than the angular velocity reference value and the number of times of the determination itself, and the number of revolutions is determined to be several. Accurately detects misfires that occur once in a while.

[0005]

In the conventional misfire detecting device for an internal combustion engine, a crank angle plate is attached to the end of the crankshaft, and a plurality of misfire detectors, for example, the outer circumference, are attached to the outer circumference of the crank angle plate. There is one in which protruding tooth portions are provided at equal intervals around the circumference, the angular velocities of these tooth portions at the time of rotation are measured by an electromagnetic pickup, and the misfire state is detected by the change of the angular velocity of the crank angle plate, that is, the tooth portion.

However, when the crank angle plate is used to detect the misfire state, the machining tolerance of the crank angle plate, that is, the tooth portion greatly affects the angular velocity.

As a result, the angular velocity at the time of misfire varies due to variations in the machining of the crank angle plate, that is, the tooth portion, and the accuracy of misfire determination is impaired, and the reliability is reduced.

Further, if the machining tolerance of the crank angle plate is improved, it is necessary to increase the material of the crank angle plate and the machining accuracy, which increases the material cost and the machining cost, resulting in a large cost and is economical. There is a disadvantage that it is disadvantageous to.

[0009]

Therefore, in order to eliminate the above-mentioned inconvenience, the present invention provides a plurality of misfire detectors on the outer periphery of a crank angle plate mounted on a crankshaft, and the angular velocities of these misfire detectors. In the misfire detection device of the internal combustion engine for measuring the misfire state by changing the angular velocity of the misfire detector, the angular velocity at the time of misfire detection is measured and stored as a correction value by measuring the angular velocity for each of the misfire detectors during deceleration. It is characterized in that a control unit for performing correction control according to a value is provided.

Further, an internal combustion engine in which a plurality of misfire detectors are provided on the outer circumference of a crank angle plate mounted on a crankshaft, and the angular velocities of these misfire detectors are measured to detect the misfire state by the change in the angular velocity of the misfire detectors. In the misfire detection device, a control unit is provided for measuring an angular velocity for each of the misfire detectors during deceleration and controlling for detecting an abnormal state of the crank angle plate due to a variation in the angular velocity of each of the misfire detectors. To do.

[0011]

According to the invention as described above, during deceleration, the angular velocity is measured for each misfire detector and stored as a correction value in the control unit, and the angular velocity at the time of misfire detection is corrected and controlled by the correction value to improve the misfire detection accuracy. I am letting you.

Further, the angular velocity is measured for each misfire detector during deceleration, and the variation in angular velocity for each misfire detector is also measured, and the control unit controls to detect an abnormal state of the crank angle plate. In addition to reducing the influence of the machining tolerance of, the crank angle plate is detected to be abnormal or broken.

[0012]

Embodiments of the present invention will be described in detail below with reference to the drawings.

1 to 4 show an embodiment of the present invention. In FIG. 2, 2 is a crankshaft of an internal combustion engine (not shown) mounted on a vehicle (not shown), and 4 is a crank angle plate.

A crank angle plate 4 is mounted on the end of the crankshaft 2, and a plurality of misfire detectors, for example, tooth portions 6 which are protrusions are provided on the outer periphery of the crank angle plate 4.

A control unit (engine control unit, ECU) 8 for measuring the angular velocity of each tooth portion 6 during deceleration of the vehicle (not shown), storing it as a correction value, and correcting and controlling the angular velocity at the time of misfire detection by the correction value. The configuration is provided.

Further, the function of measuring the angular velocity of each tooth portion 6 during deceleration of the vehicle (not shown) and controlling the abnormal state of the crank angle plate 4 by the variation of the angular velocity among the misfire detectors is also provided. It is provided in addition to the control unit 8.

More specifically, as shown in FIG. 2, the tooth portion 6 has six first to sixth tooth portions 6-1 and 6 arranged at the outer periphery of the crank angle plate 4 and at equal intervals around the circumference. -2, 6-
3, 6-4, 6-5, 6-6.

The control unit 8 controls the vehicle during deceleration (not shown) and during fuel cut control.

That is, as shown in FIG. 3, the first to sixth tooth portions 6-1, 6-2, 6-3, 6 are provided after a predetermined time FCPT has elapsed after the fuel cut control was started. -4, 6
The angular velocity OMG60 for each of -5 and 6-6 is measured by the electromagnetic pickup 10 connected to the control unit 8.

The angular velocity gradient OMGK during deceleration,
That is, the first to sixth tooth portions 6-1, 6-2, 6-3, 6
-4, 6-5, 6-6, the angular velocity gradient OMGK n ,
Calculate by the formula below. OMGK n = (amount of change in angular velocity from a to b) / (time from a to b) = {(OMG60 1-1 -OMG60 1-2 )} / (Tb-Ta) (n = 1 to 6)

Further, the first to sixth tooth portions 6-1 and 6-
The standard deviation SDK n of the angular velocity gradient OMGK n for each of 2, 6-3, 6-4, 6-5, and 6-6 is calculated. At this time,
Normal standard deviation SDK and first to sixth tooth portions 6-1 and 6
The standard deviation SDK n of the angular velocity of the inclination OMGK n for each -2,6-3,6-4,6-5,6-6, in the following relationship. SDK ≒ SDK n

Further, a preset standard deviation value SDK1 is stored in the control unit 8 in advance, the standard deviation SDK n of the inclination OMMGK n of the angular velocity and the first preset standard deviation value SDK1 are compared, and if SDK n ≤SDK1 The correction is performed only on.

First to sixth tooth portions 6-1, 6-2, 6-
In order to make the angular velocities of 3, 6-4, 6-5, and 6-6 comparable, the value at the same time, for example, the time Tb, that is, the standard angular velocity OMGKS n is calculated by the following formula. At this time, the average SDKAV of the standard deviation SDK can be used instead of the average OMGAV of the angular velocity OMG.

[Equation 1]

Then, the first to sixth tooth portions 6-1 and 6-
Standard angular velocity OM of 2, 6-3, 6-4, 6-5, 6-6
The standard deviation SDKS of GKS is calculated, and this standard deviation SDK
S is compared with the second set standard deviation value SDKS1 stored in advance, and the first to sixth tooth portions 6-1, 6-2, 6-3,
6-4, 6-5, and 6-6 are used to determine the machining variation state of the standard angular velocities OMGKS n , and the first to sixth tooth portions 6-
The machining variations of the standard angular velocities OMGKSn of 1 , 6-2, 6-3, 6-4, 6-5, and 6-6 are stored as an average difference (see the following formula and table).

[Equation 2]

[Table 1]

In the comparison between the standard deviation SDKS and the second set standard deviation value SDKS1, SDKS ≧ SDKS
1, that is, the processing variation is the second set standard deviation value SDKS
When one or more states are established x times consecutively, it is determined that the crank angle plate 4 is abnormal or damaged, and the driver is notified by a warning means (not shown) such as lighting of a lamp. , The misfire detection control is stopped.

Further, in the comparison between the standard deviation SDKS and the second set standard deviation value SDKS1, SDKS <SDKS
In the case of 1, the first to sixth tooth portions 6-1, 6-2, 6
-3, 6-4, 6-5, 6-6 processing variation OMG
VAL is calculated, and the first to sixth tooth portions 6-1, 6-2,
Processing variation OM for each of 6-3, 6-4, 6-5, 6-6
The change amount VAL of GVAL is calculated.

That is, the calculation of the variation amount VAL of the machining variation OMGVAL is the same as the previous machining variation OMGVALo.
It is obtained by subtracting the machining variation OMGVALnew of this time from ld, and the change amount VAL at this time is
It does not change abruptly except when an unexpected change such as biting a foreign object occurs, and a sudden abnormal state is detected by comparing with a preset change amount VAL1 stored in advance.

First to sixth tooth portions 6-1, 6-2, 6-
Processing variation OMGV for each of 3, 6-4, 6-5, and 6-6
AL is stored in a memory unit (not shown) in the control unit 8 and used as a correction value for the angular velocity OMG60 which is a detection signal at the time of misfire detection.

Next, the operation will be described with reference to the misfire detection flowchart of FIG.

A misfire detection program in the control section 8 is started (100) by driving an internal combustion engine (not shown) mounted on a vehicle (not shown).

Then, fuel cut during deceleration (Fuel /
cut) It is judged whether or not control is in progress (102),
If this determination (102) is NO, the determination (102)
Is repeated until it becomes YES, and the judgment (10
If YES in 2), it is determined (104) whether or not FCPT has elapsed for a predetermined time.

When the determination (104) is NO, it is determined whether the fuel cut control during deceleration is being performed (1
02), if the determination (104) is YES, the first to sixth tooth portions 6-1, 6-2, 6-3, 6 at the time of deceleration
The inclinations OMGK n of the angular velocities of −4, 6-5, and 6-6 are measured and calculated by the following equation (106). OMGK n = (amount of change in angular velocity from a to b) / (time from a to b) = {(OMG60 1-1 -OMG60 1-2 )} / (Tb-Ta) (n = 1 to 6)

Next, the first to sixth tooth portions 6-1 and 6-
Calculating a standard deviation SDK n slope OMGK n of the angular velocity of each 2,6-3,6-4,6-5,6-6 (108).

Furthermore, the comparison between the standard deviation SDK n slope OMGK n of the control unit 8 pre-stored set standard deviation in SDK1 and the angular velocity (110), the comparison (11
If 0) is NO, that is, if SDK n > SDK1, it is determined whether the fuel cut control during deceleration is being performed (1
Returning to 02), if the comparison (110) is YES, that is, if SDK n ≦ SDK1, correction is executed. At this time, the first to sixth tooth portions 6-1, 6-2, 6-3, 6
In order to make the angular velocities of −4, 6-5, and 6-6 comparable, for example, the standard angular velocity OMGKS n that is the value at the time Tb.
Is calculated according to the following equation (112). OMGKS n = OMGAV × Tx

Then, the first to sixth tooth portions 6-1 and 6-
Standard angular velocity OM of 2, 6-3, 6-4, 6-5, 6-6
The standard deviation SDKS of GKS is calculated (114), and this standard deviation SDKS and the second set standard deviation value SD stored in advance.
Compare (116) with KS1.

In this comparison (116), if YES, that is, in the condition of SDKS ≧ SDKS1 and the machining variation SDKS is equal to or more than the second set standard deviation value SDKS1, the above condition is continuously satisfied x times. Only when it is determined that the crank angle plate 4 is abnormal or damaged, the driver is notified (118) by, for example, lighting a lamp, and the misfire detection control is stopped (120) to end (132). ) Is moved to.

At this time, if the state that the machining variation SDKS is equal to or more than the second set standard deviation value SDKS1 is not established continuously x times, the process is repeated until it is continuously established x times.

Further, in the comparison (116), if NO, that is, if SDKS <SDKS1, machining variation O
MGVAL, that is, the first to sixth tooth portions 6-1 and 6-
The machining variation OMGVAL n for each of 2, 6-3, 6-4, 6-5 and 6-6 is calculated by the following equation (122). OMGVAL n = OMGKS n / OMGKSAV

Furthermore, the variation amount VAL of the machining variation OMGVAL, that is, the first to sixth tooth portions 6-1, 6-2,
Change amount VAL for every 6-3, 6-4, 6-5, 6-6
n is calculated by the following formula for subtracting the current machining variation OMGVALnew from the previous machining variation OMGVALold (124). OMGVALold n -OMGLnew n = VAL n ( n = 1~6)

Then, the change amount VAL n is compared with the preset change amount VAL1 stored in advance (126). If the comparison (126) is NO, that is, VAL n > VAL1, the above-mentioned crank angle plate 4 is used. Abnormality or damage notification (118) and stop of misfire detection control (12)
0) side, and if this comparison (126) is YES, that is, if VAL n ≦ VAL1, machining variation OMG.
VAL, that is, the first to sixth tooth portions 6-1, 6-2,
6-3, 6-4, 6-5, 6-6 processing variation OM
GVAL n is calculated by the following formula for each 6 tooth portion, and after calculation, it is stored in the memory unit (not shown) in the control unit 8 (12
8). OMGVAL n = OMGVALold n × α1 + OMG
Lnew n × α2

At this time, the relationship between the set values α1 and α2 in the above equation is α1> α2. By setting the relationship between the set values α1 and α2, weighting is performed according to the difference in the amount of captured data.
MGVALold data and this machining variation OMG
This is due to the reliability of the VALnew data.

Further, the machining variation OMGVAL is the angular velocity OM used for misfire detection, as is clear from the equation below.
It is used as a correction value for G60 (130). OMG6
0 n = OMG60 (measured value) × OMGVAL

Then, the misfire detection program is ended (132).

As a result, the influence of the machining tolerance of the crank angle plate 4 on the angular velocity can be eliminated, it is not necessary to improve the machining tolerance of the crank angle plate, and the material cost and machining cost of the crank angle plate can be reduced. As a result, the cost is low and it is economically advantageous.

Further, it is possible to reliably detect a hardware abnormality such as foreign matter mixed into the crank angle plate 4 or damage to the crank angle plate 4, which is practically advantageous.

Further, when the control unit 8 detects a misfire,
First to sixth tooth portions 6-1, 6-2, 6-3, 6-4,
By correcting the angular velocity in consideration of machining variations for each of 6-5 and 6-6, the misfire detection accuracy can be improved and the reliability of the device can be improved.

[0047]

As described in detail above, according to the present invention, a control unit is provided for measuring the angular velocity for each misfire detector during deceleration and storing it as a correction value, and correcting and controlling the angular velocity at the time of misfire detection. Therefore, it is possible to eliminate the influence of the machining tolerance of the crank angle plate on the angular velocity, it is not necessary to improve the machining tolerance of the crank angle plate, the material cost of the crank angle plate and the machining cost can be made low, and the cost can be reduced. It is inexpensive and economically advantageous. Further, when misfire is detected by the control unit, the misfire detection accuracy can be improved and the reliability of the device can be improved by correcting the angular velocity in consideration of the processing variation for each misfire detector. .

Further, since the angular velocity is measured for each misfire detector during deceleration, and the control unit is provided for controlling to detect the abnormal state of the crank angle plate due to the variation of the angular velocity among the misfire detectors, the crank angle plate is controlled. It is possible to reliably detect a hardware abnormality such as mixing of foreign matter and damage to the crank angle plate, which is practically advantageous.

[Brief description of drawings]

FIG. 1 is a flowchart for misfire detection showing an embodiment of the present invention.

FIG. 2 is a schematic configuration diagram of a misfire detection device for an internal combustion engine.

FIG. 3 is a schematic diagram showing a slope of each speed during deceleration.

FIG. 4 shows misfire detection parameters, (a) shows a misfire detection crank angle signal, and (b) shows C after waveform shaping.
R signal, (c) normal combustion of angular velocity OMG60, (d) ignition signal, (e) rotation pulsation during normal combustion, (f) fuel cut ( Fue
(l / cut) is a diagram showing rotational pulsation, and (g) is a diagram showing machining variations of 6 teeth.

[Explanation of symbols]

 2 crankshaft 4 crank angle plate 6 teeth 6-1 to 6-6 1st to 6th teeth 8 control unit 10 electromagnetic pickup

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. 5 Identification code Internal reference number FI technical display location G01M 15/00 Z 7324-2G

Claims (2)

[Claims]
1. An internal combustion engine in which a plurality of misfire detectors are provided on the outer periphery of a crank angle plate mounted on a crankshaft, and the misfire state is detected by measuring the angular velocities of these misfire detectors and detecting the change in the angular velocity of the misfire detectors. In the misfire detection device, the internal combustion engine is characterized in that a control unit is provided for measuring the angular velocity for each of the misfire detectors during deceleration, storing the correction as a correction value, and correcting and controlling the angular velocity at the time of misfire detection by the correction value. Misfire detection device.
2. An internal combustion engine in which a plurality of misfire detectors are provided on the outer periphery of a crank angle plate mounted on a crankshaft, and angular speeds of these misfire detectors are measured to detect a misfire state based on changes in the angular speeds of the misfire detectors. In the misfire detection device, a control unit is provided for measuring an angular velocity for each of the misfire detectors during deceleration and controlling for detecting an abnormal state of the crank angle plate due to a variation in the angular velocity of each of the misfire detectors. Internal combustion engine misfire detection device.
JP5166011A 1993-06-11 1993-06-11 Misfire detection device for internal combustion engine Expired - Fee Related JP3057962B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP5166011A JP3057962B2 (en) 1993-06-11 1993-06-11 Misfire detection device for internal combustion engine

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP5166011A JP3057962B2 (en) 1993-06-11 1993-06-11 Misfire detection device for internal combustion engine

Publications (2)

Publication Number Publication Date
JPH06346779A true JPH06346779A (en) 1994-12-20
JP3057962B2 JP3057962B2 (en) 2000-07-04

Family

ID=15823247

Family Applications (1)

Application Number Title Priority Date Filing Date
JP5166011A Expired - Fee Related JP3057962B2 (en) 1993-06-11 1993-06-11 Misfire detection device for internal combustion engine

Country Status (1)

Country Link
JP (1) JP3057962B2 (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2007187021A (en) * 2006-01-11 2007-07-26 Denso Corp Rotary angle detection device
CN104713732A (en) * 2015-04-10 2015-06-17 潍柴西港新能源动力有限公司 Test bench for signal generator of natural gas engine

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2007187021A (en) * 2006-01-11 2007-07-26 Denso Corp Rotary angle detection device
JP4552863B2 (en) * 2006-01-11 2010-09-29 株式会社デンソー Rotation angle detector
CN104713732A (en) * 2015-04-10 2015-06-17 潍柴西港新能源动力有限公司 Test bench for signal generator of natural gas engine

Also Published As

Publication number Publication date
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