JPS6035171A - Ignition timing control device for internal-combustion engine - Google Patents

Abstract

PURPOSE:To properly and rapidly judge abnormality by enabling a knocking detector or a detecting circuit including said detector to be judged to be abnormal by detecting the presence of an electric output signal from said knocking detector caused by mechanical vibration produced at starting of an engine. CONSTITUTION:When an internal combustion engine is started by a starter and enters its operation state, very large mechanical vibration is produced in an engine body. A large electric output signal generated from a knocking detector 2 in responce to said mechanical vibration is inputted to a microcomputer 4-2 via a BPF 4-1 provided in an ignition timing control device 4. When an interruption signal caused by starter-on stays at an H level, a peak value of the aforesaid output signal is investigated, and when a peak value exceeding a prescribed fault deciding level appears, the knocking detector 2 is judged to be normal. Then, in responce to this decision result, ignition timing is controlled or corrected, allowing an igniter 5 to be controlled.

Description

[Detailed Description of the Invention] Industrial Application Field The present invention detects knocking by mechanical vibrations or sounds generated inside and outside the cylinder due to pressure fluctuations in the cylinder of an internal combustion engine stand in an automobile, etc., and a knocking signal is generated. An ignition timing control device for internal combustion engines that has a timing adjustment function.
In particular, the present invention relates to improvements in means for determining failure of the knocking detection means itself in this type of control system.

Conventional technology and problems Knocking phenomenon that occurs in internal combustion engines such as automobiles (1) IE caused by ignition sparks during acceleration of internal combustion engines, etc.
A constant flame? The air-fuel mixture self-ignites and burns explosively before reaching the end! f1 that occurred from
Nika wave is generated in Pebeton cylinder 1ki + J1t
About G iQ-, there is a /1, advance the ignition timing,
In the early 1990s, the internal combustion engine was started with the L-4IILF-, and especially the internal combustion engine equipped with a supercharger (the IE L1II T was very expensive). J's. / ``Knocking phenomenon is more likely to occur.'' By the way, there is a weak knocking phenomenon.
2/゛ Nori) and (3L, fuel consumption !If :I)ノ and 1 →
Increased to! Suri 4'1. and t), /"Lee"ng overIα
(J is an internal combustion engine, so for J-, there are two places on the main body of the internal combustion engine, for example, 'Schilling-1' 11).ゝlgin/j by mi, ++ ＞'11・f1 cock's (mechanical pregnancy i+'JJ 1.: Jt shake one nn city, ne cow t
! '1. ,/Me, this issue) 1 Den I-O sets the predetermined value to 11!
! Er, = 1 and 1, Noi TO concP - 7 ~ I ζ is [
7) ``Tsuku present.-I and M are determined so that each knocking phenomenon is detected at the same time as it occurs, and the ignition timing is automatically set by 9 [Y et al.
Undesirable, (Turning the 9 elephants, the best way to ignite is to control 11-◇ from 1f11 and 411')\(
7, 1, f, Nino, 1, f)': K 5'; Tue 11. 'i
lil eye+'t oil g place ni, 1 tie"C!;t
, ゛(-1st, :intervention5i :re7i :bnodzkin fj control sea), each constituent link tree of j system,'141 the reliability of that circuit 4) 1 7.1 > r i) request (gas) becomes harsh,
The system is (sufficiently suitable for the first time) Vice 17B”
Do g1. In order to ensure that the reliability of this circuit is
'Shijo's origin・1-1'Totokikonozu) - Fern detector each 1: jl (fast and reliable detection IJ-'i: 1, ko 41
, (appropriate i for two: Ht ii'' is taken ζ) non-i 2'i t!t with d is recognized, above-) becomes ゛, [ζ.

However, )゛! For example, as a gimp detector, if the electric wire: 1- is used, 4'1 (if there is one, then 1 electric wire 4. complete itself is a DC one-wire disconnection state, one wire h60)-(:, that ) of the Luha curve -) 4 "l ~ (fault detection 1-1 (42 λ, 1
Schiff, normal free time 7-be 1-0), J Raijo-
1 Simple method...! Straight (5-apply 1, (-4') LL is quite l -1) l ko, 1 So, to this fish -) I ℃ solution) k plan and 1 no CI Th + certain was done In one of the prior art, under the operating conditions of an internal combustion engine, d:
In the evening, monitor the output signal level from a specific part of the knocking detection/processing circuit system, and if the signal level is lower than normal or virtually zero, the knocking detector or its It has been determined that there is a failure in the circuit of the system described in I.

However, in this method, it is necessary to detect minute high-frequency single movements of the internal combustion engine at low rotation speeds and when the load is light. Therefore, the ignition timing control I device requires an amplifier with a high gain of 1q, which has an amplification degree of several tens to 100 times as much as that of the ignition timing control device.

However, using a high-gain amplifier is extremely costly, and the signal-to-noise ratio deteriorates due to the introduction of various electrical noises (ignition noise, generator noise, etc.), making accurate knocking detection difficult. There were several problems.

OBJECTS OF THE INVENTION The present invention thus provides a novel technique for solving the above-mentioned problems in the prior art. The mechanical vibration that occurs when the starter starts is extremely large! The main objective is to detect the presence or absence of a signal from the knocking detector at that time, and to quickly and accurately troubleshoot the knocking detector. be.

First Structure/Operation and Actual Sample The structure of the present invention will be explained below. FIG. 1 shows a block diagram of a first embodiment embodying the idea of the present invention. In FIG.
A knocking detector is a knocking detector consisting of a piezoelectric element or a power generating coil, etc., and is capable of detecting vibrations or sound waves of the engine body due to engine knocking. Here, in the case of a piezoelectric element type knocking detector, a piezoelectric ceramic that accelerates ferroelectricity, for example, Pb.(1-i, Zr) is used.
・Three-component zircon made by solid solution complexing 03 with a third component・
Titanic acid-based compounds are preferred, and they are particularly used in the bimol 6-FJ'1 (carrying beam) type (photography (4: form fatigue).
L. J, I,:, Power generation-(Using Ile!, Ninotskin,',,) 4! In the output device, ti&, 9, 1
￥ (-tor), '1. 1; 1 magnetostrictive type, /゛tsuki:
/G Q output ν5 internal 1. :, '+isu, internal combustion) ri) gate swing 1lIIlko, 尤(0, power generation -1-il's 71 return 1
lZ) (: Support 1 stone/,, l' pinching, -zono (・沫東MITSU 1α iguization (J up,] Ile to electric message?: occurs nu 1b
In particular, 5, 3 (3 (, 粁 lit μm 1? start) p can N zeruden 〈8') 21 evening j (no s 4 length - ta decreases by +1).

A1. ll, )ノ(ng detector) - Detects the right focus of knocking from the HA Buddha signal and determines the ignition timing.
i"4% '1α("dsu7>.(5 is determined by the ignition timing control device';
ItaC is the first person to send ignition Iha wings to the Recca coil.
゛5, b is the start [11] start jinshi sending to the start set 1t-9...jshi main ゛r-, and 7
<tl, r\)l/i! J 'i%; source eiru 5, the flame timing control device 4 is configured as follows (, - as described (J'
Stay in T.

2 (Su゛, A 'l is Pandobasnoirk (1'') lower F3.
・Remove one signal from the other side.

4-2 is a tool that performs knocking detection and ignition timing control.
)-Tzoik n Tl'-,zhifu(,1t-(
, A/') - (,, △[] Contains a converter, (Both have multiple analog input terminals, I"U") and current input/output terminals), 1 /l -, 3 is '1 ゚)Pamai 1 n 1, -Thus, the complement of ignition 11￥light +
[-,? tt to Ana [; Gumirow 1 conversion 1Jru 1] Hey (・It is a exchange device. 4 / Positive it → Nona 11) 1゛ Converted to Denbon 1, ′: Sadoka 1iar Akeshin Tsubasa Iku゛-)
- (This is a voltage/lightning 'JATh converter for converting to 4.

Next, the core idea of the present invention is to detect failure of the knocking detector. 'lJ1, in the case of general heavy duty vehicles, those using electric motors are widely used. In other words, the beginning of the internal combustion engine;
” Sometimes, along with the 77 rank axis of the engine body, 1.
7 phosphorus)) ``+'': ~... and the binion gear in the starter are engaged, and then! - Due to the rotation of the pinion gear and the sig A by the electric motor in the cage, an extremely large mechanical swing J is generated in the ti!f gate * land, but as shown in Fig. The knocking detector 2 is installed on the cylinder 1 [-1] of the internal combustion engine F, II 1. When the large mechanical vibration a+ 17 -) 1 knocking noise detection 2) is generated, a large electrical output signal 8 is generated - (i. Therefore, the subsequent operation is shown in Fig. 2 Minja-1-
・Explanation using II-Char 1 in Figure 3.4.5
Ru.

Knocking detector 2 due to mechanical vibration generated during startup
The electrical output signal (second bloom) from Jllll at the time of ignition
The signal from the controller 4I passes through a bandpass filter 4-1 to remove noise and the like, and enters the input port of the AD converter of the 1-chip micrometer 4-2. On the other hand, the starter switch θ in the passenger compartment sends a start signal to the starter 3, that is, the starter is turned on (Fig. 2 ■).
At the same time, this signal is also sent to the interrupt input terminal of the 1-deep microcomputer. One chip microcontroller is
As shown in the flowchart of FIG.
1 rotation speed h that calculates the engine rotation speed by measuring the ignition signal interval time of the igniter 5 input to the chip microcomputer
I calculation", AD converts the signal of the knocking detector to check the presence or absence of knocking. , Calculate the advance angle [Ignition timing correction operation C) 1. The value of the ignition timing correction is set to a safe retardation state according to the failure detection state of the knocking detector and the detection circuit including the knocking detector detected in the interrupt routine. The main routine is repeatedly executed, which consists of processing such as "11 JI output 1 at ignition" which outputs the value of the ignition 1!11 correction program to the ignitor 5. However, when an interrupt occurs due to the starter-on signal, the main routine processing is temporarily interrupted, and the interrupt processing routine shown in the flowchart of FIG. 4 is executed. In this interrupt routine, first, a "failure flag" indicating whether or not the detector has failed is set for initialization (゛T+IGH''), and then the electrical noise generated when starting the starter is removed. - wait for a certain period of time (several ms) without doing anything.After that, while the starter ON signal is LI I G +-1,
Peak value V of the knocking detector signal (second [). a
Check k one after another.

10- Here, the failure flag is used within this specification as a name on rough 1 to software in the microcontroller, and its function is to identify when the flow of program execution is changed by a judgment statement. It is something to be used.

At the time of failure: Failure flag = “1”... (HIGH)
Normal: Failure flag -r (011...(1-O)
W > I to detect the peak value of the knocking detector signal
FIG. 5 shows the flowchart of Nabuchin.

The frequency of the output signal of the knocking detector is constant (approximately 7KH)
2), the zero intersection of the signal is detected, the time from that point to the peak is waited, and the AID is detected at the peak position.
By performing the transformation, the peak value of the signal, V,. Detect ak. If a peak value higher than a predetermined failure determination level appears ((■) in FIG. 2), the knocking detector is normal, and the failure flag is reset. If the peak value does not exceed the failure determination level, no change occurs in the operation of the failure flag. If the starter on signal becomes LOW,
Extract from this routine and move execution to the main routine.

In the main routine, "knocking detector failure processing"
The routine corrects the ignition timing according to the failure state of the knocking detector and detection circuit detected during the interrupt routine. A flowchart showing details of this failure processing is shown in FIG. 6. Here, first, when the engine rotational speed exceeds a certain rotational speed (for example, 2000rnllll), the "failure flag" is set to HIGH depending on the failure state of the detector detected in the interrupt routine earlier, that is, if there is a failure.
1-1, so in that case, the corrected ignition timing output to the igniter should be set to the specified retard side, considering the safety of the engine.

An example of import will be explained below. A flowchart of the failure detection routine of the second embodiment is shown in FIG. The circuit is exactly the same as the first embodiment, so a description thereof will be omitted. The second embodiment is a combination of the detection of engine vibration at startup in the first embodiment and the detection based on the magnitude of the knock determination level created at the time of knock detection. In other words, when the engine rotates at high speed and the mechanical vibration of the engine body becomes extremely large, the output signal of the knocking detector increases by 1 novel, which can easily cause the knocking detector to malfunction or deteriorate its characteristics. Can be judged. Therefore, the one-chip microcomputer in the ignition timing control device 4 averages the output signal of the knocking detector to detect knocking, thereby creating a knocking determination level.

The magnitude of this knocking determination level is detected, and if it is below a preset reference level, it is determined that the knocking detector is in a failure state. By performing a logical sum (OR) of the results of failure detection based on the determination level and failure detection based on discharge in the first embodiment, failures in the knocking detector can be detected more reliably. Note that the logical sum here refers to whether it is the entire flowchart in Figure 7 or the case where a failure is determined by comparing the average value of the knocking detector signal with the reference level, when expressed in a flowchart (program flow). Even in state 13-, the knocking detector is determined to be faulty (logical sum operation)
It is supposed to be done.

Effects of the Invention As is clear from the above description, the present invention solves the above-mentioned problems of the prior art based on the structure described in the claims, and quickly resolves the failure of the knocking detector. In addition to effectively achieving the intended purpose of making accurate judgments, the output signal of the knocking detector at the time of starting the starter is Since the output signal (several 100 mV) is much larger (several 100 mV) than the output signal (several mV) of , which can be realized very effectively, and the effect of this pushing device is remarkable.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the shell-1/I-direction configuration of a first embodiment embodying the concept of the ignition timing control device for an internal combustion engine of the present invention, and FIG. 1
2 is a timing chart for explaining the operation of the illustrated first embodiment, showing signal waveforms of important parts in FIG. 1. FIG. 3, 4, 5, and 6 are flowcharts i~ related to the first embodiment, respectively, and have been created for the purpose of understanding the operation. FIG. 7 is a flowchart for explaining the operation of the second embodiment of the present invention. In the figure, 1... Internal combustion engine main body, 2... Knocking detector, 3... Electric motor type starter, 4... Ignition timing control device, 4-1... Band pass filter, 4 -2...1
Chip microcomputer, 4-3...DA converter, 4-4...Voltage/current converter, 5...Igniter, 6...Starter on switch, 7...Battery power supply. Agent Asamura nF'i Figure 5 Off view

Claims (1)

[Claims] (1) A knocking detector that detects vibrations caused by a knocking phenomenon in an internal combustion engine, an ignition timing control circuit that generates an ignition timing control signal in response to an electrical output signal from the knocking detector due to the knocking phenomenon, and an ignition timing control circuit that generates an ignition timing control signal in response to an electrical output signal from the knocking detector due to the knocking phenomenon. In an ignition timing control system having an ignition device that generates an ignition signal in response to a timing control signal; in particular, the presence or absence of an electrical output signal of the knocking detector due to mechanical vibrations generated in the main body of the internal combustion engine when the -M conduction occurs. An ignition timing control device for an internal combustion engine, comprising means for determining whether the knocking detector or its detection circuit including the knocking detector is in a normal or malfunctioning state by detecting the knocking detector. . (2. In the apparatus according to claim 1; a first signal outputted from the means for determining the state of the knocking detector, which does not indicate that the knocking detector is in a failure state; A Ritzking judgment level is created by averaging the electrical output signals from the knocking detector due to the knocking phenomenon, and a comparison of the knocking judgment level with a preset reference level determines whether the detector has failed. 11. An ignition timing control device for an internal combustion engine, characterized in that the means for determining a failure of the knocking detector is determined by performing a logical sum with a second signal representing the state of the knocking detector.